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21.
22.
Lipoxygenase inhibiting and antioxidant oligostilbene and monoterpene galactoside from Paeonia emodi
Riaz N Malik A Rehman AU Ahmed Z Muhammad P Nawaz SA Siddiqui J Choudhary MI 《Phytochemistry》2004,65(8):1129-1135
Paeoninol and paeonin C, oligostilbene and monoterpene galactoside, have been isolated from the methanolic extract of the fruits of Paeonia emodi. Their structures have been assigned on the basis of spectral analysis including 1D and 2D NMR techniques. In addition, 4-hydroxybenzoic acid 3, gallic acid 4 and methyl gallate 5 have also been reported for the first time from this species. Compounds 1 and 2 have displayed potent inhibitory potential against enzyme lipoxygenase in a concentration-dependent fashion with the IC(50) values 0.77 and 99.5 microM, along with ABTS(.+) radical quenching activity with IC(50) values of 147.5 and 498.2 microM, respectively. 相似文献
23.
Sibanda W Pillay V Danckwerts MP Viljoen AM van Vuuren S Khan RA 《AAPS PharmSciTech》2004,5(1):128-141
A Plackett-Burman design was employed to develop and optimize a novel crosslinked calcium-aluminum-alginatepectinate oilisphere
complex as a potential system for the in vitro site-specific release ofMentha piperita, an essential oil used for the treatment of irritable bowel syndrome. The physicochemical and textural properties (dependent
variables) of this complex were found to be highly sensitive to changes in the concentration of the polymers (0%–1.5% wt/vol),
crosslinkers (0%–4% wt/vol) and crosslinking reaction times (0.5–6 hours) (independent variables). Particle size analysis
indicated both unimodal and bimodal populations with the highest frequency of 2 mm oilispheres. Oil encapsulation ranged from
6 to 35 mg/100 mg oilispheres. Gravimetric changes of the crosslinked matrix indicated significant ion sequestration and loss
in an exponential manner, while matrix erosion followed Higuchi's cube root law. Among the various measured responses, the
total fracture energy was the most suitable optimization objective (R
2 =0.88, Durbin-Watson Index=1.21%, Coefficient of Variation (CV)=33.21%). The Lagrangian technique produced no significant
differences (P>.05) between the experimental and predicted total fracture energy values (0.0150 vs 0.0107 J). Artificial Neural Networks,
as an alternative predictive tool of the total fracture energy, was highly accurate (final mean square error of optimal network
epoch≈0.02). Fused-coated optimized oilispheres produced a 4-hour lag phase followed by zero-order kinetics (n>0.99), whereby
analysis of release data indicated that diffusion (Fickian constantk
1=0.74 vs relaxation constantk
2=0.02) was the predominant release mechanism. 相似文献
24.
The maximum productivity of -glucosidase by Saccharomyces cerevisiaerecombinants under the control of GALI promoter was 100 IU l–1 h–1. The highest productivity of -glucosidase by a S. cerevisiae recombinant was 16-fold more than that supported by Cellulomonas biazotea. The recombinants also co-produced ethanol from cellobiose: maximum product yield and productivity were 0.5 and 1.1 g ethanol g–1 cellobiose and g ethanol l–1 h–1, respectively. 相似文献
25.
Ahmad Shoaib Amin René H.J. Peters Maaike Verstraaten Arthur A.M. Wilde Eugène M. Buijs 《Netherlands heart journal》2015,23(3):182-189
BackgroundPatients with acute-onset symptomatic atrial fibrillation (AF) can be treated with flecainide. However, flecainide may induce arrhythmias and/or exaggerate heart failure. Therefore, validated markers to predict the efficacy of flecainide and prevent adverse effects are required. We hypothesised that lower NT-proBNP plasma levels correlate with higher success rates of cardioversion with flecainide in patients with AF.MethodsIn this prospective single-centre study, we included 112 subsequent patients with acute-onset (< 24 h) symptomatic AF. Patients with symptoms of heart failure and ECG signs of ischaemia were excluded. Baseline laboratory measurements, including NT-proBNP, were done. Echocardiograms were performed ~ 2 weeks after restoration of SR.ResultsCardioversion with flecainide was successful in 91 patients (87 %). NT-proBNP was lower in patients with successful cardioversion (P < 0.001). Logistic regression indicated NT-proBNP as an independent predictor of successful cardioversion. A cut-off NT-proBNP value of 1550 pg/ml provided optimal test accuracy to predict successful cardioversion.ConclusionIn patients with < 24 h of symptomatic AF, NT-proBNP levels up to 1550 pg/ml correlate with high success rates (94 %) of cardioversion with flecainide. Conversely, NT-proBNP higher than 1550 pg/ml correlates with poor success rates (36 %). Further research is needed to validate the predictive value of NT-proBNP for successful cardioversion with flecainide. 相似文献
26.
Creatine (Cr) is naturally produced in the body and stored in muscles where it is involved in energy generation. It is widely used, especially by athletes, as a staple supplement for improving physical performance. Recent reports have shown that Cr displays antioxidant activity which could explain its beneficial cellular effects. We have evaluated the ability of Cr to protect human erythrocytes and lymphocytes against oxidative damage. Erythrocytes were challenged with model oxidants, 2, 2''-azobis(2-amidinopropane) dihydrochloride (AAPH) and hydrogen peroxide (H2O2) in the presence and absence of Cr. Incubation of erythrocytes with oxidant alone increased hemolysis, methemoglobin levels, lipid peroxidation and protein carbonyl content. This was accompanied by decrease in glutathione levels. Antioxidant enzymes and antioxidant power of the cell were compromised while the activity of membrane bound enzyme was lowered. This suggests induction of oxidative stress in erythrocytes by AAPH and H2O2. However, Cr protected the erythrocytes by ameliorating the AAPH and H2O2 induced changes in these parameters. This protective effect was confirmed by electron microscopic analysis which showed that oxidant-induced cell damage was attenuated by Cr. No cellular alterations were induced by Cr alone even at 20 mM, the highest concentration used. Creatinine, a by-product of Cr metabolism, was also shown to exert protective effects, although it was slightly less effective than Cr. Human lymphocytes were similarly treated with H2O2 in absence and presence of different concentrations of Cr. Lymphocytes incubated with oxidant alone had alterations in various biochemical and antioxidant parameters including decrease in cell viability and induction of DNA damage. The presence of Cr attenuated all these H2O2-induced changes in lymphocytes. Thus, Cr can function as a blood antioxidant, protecting cells from oxidative damage, genotoxicity and can potentially increase their lifespan. 相似文献
27.
Riaz Ur Rehman Muhammad Fayyaz Chaudhary Khalid Mahmood Khawar Gang Lu Abdul Mannan Muhammad Zia 《Biologia》2014,69(3):341-349
Present study describes rapid in vitro propagation of Caralluma tuberculata, a traditional medicinal plant, and antioxidant potential of calli and plants extracts. The highest callus induction rate (93.3%) with maximum weight of calli 5.2 g was achieved from shoot tip explants on MS medium supplemented with 9.04 μM 2,4-D and 4.44 μM BA. The maximum shoot induction rate (71.1%) with mean number of shoots 3.66 ± 1.53 and 4.6 cm average shoot length was observed on 13.32 μM BA, 4.52 μM 2,4-D and 2.89 μM GA3 appended in MS medium. The developed shoots were best rooted in the presence of 5.07 μM IAA with 3.0 ± 0.15 roots per plantlet. The plants were successfully acclimatized under in vivo conditions. The plants and calli extracts exhibited good antioxidant activities, however, plant extract activities were more pronounced. The phenolic compounds in plant and calli extracts were 0.16% and 0.057%, respectively. While the flavonoids were 0.092% in plant and 0.039% in calli extract. Total Phenolics, flavonoids; DPPH radical scavenging activity and reducing power potential distributed among different fractions depending upon polarity of the solvent. The highest DPPH scavenging activity and reducing power was exhibited by water fractions; 4.95 mg/mL and 0.729 OD at 10 mg/mL, respectively. The micropropagation protocol can be successfully used for large-scale multiplication and conservation of germplasm of this threatened plant. Furthermore, antioxidant value describes importance of this valuable plant as food and medicine. 相似文献
28.
M.A. Sandhu Z.U. Rahman A. Riaz S.U. Rahman I. Javed N. Ullah 《European journal of histochemistry : EJH》2010,54(2)
The objective of this study was to determine the distribution of somatotrophs and lactotrophs and conduct a morphometrical analysis of immunoreactive somatotrophs and lactotrophs in the pituitary glands of White Leghorn Hens (Gallus domesticus) during the period of induced moult. We divided the periods of induced moulting into three phases viz. 7, 14 and 21 days. The labeled alkalinephsphatase method with anti-GH (growth hormone) and anti-PRL (prolactin) as a primary antibody was used to detect somatotrophs and lactotrophs, in the midsagital sections of chicken adenohypophysis. Immunohistochemistry showed that somatotrophs are not only confined to the cephalo-caudal axis but can also be found in the caudal lobe; while lactotrophs were distributed in both lobes of the anterior pituitary gland at all stages of moulting (7, 14 and 21 days). Lactotrophs were of different shapes but somatotrophs were oval to round in morphology. At the given stages of induced moulting, some hypertrophied lactotrophs were also present after 7 days of induced moult in the anterior pituitary gland. However, there were moulting-related changes: from 7 to 21 days of induced moulting the immunoreactive-PRL cell population decreased, while the mean lactotroph size was more than that of somatotrophs. Basic quantitative and morphological information relating to somatotrophs and lactotrophs during the period of induced moult in laying hens is reported here and the changes brought about by induced moulting are restricted to PRL positive cells rather than GH positive cells.Key words: Moult, pituitary gland, somatotrophs, lactotrophs, chicken. 相似文献
29.
30.
Farooqi AA Mukhtar S Riaz AM Waseem S Minhaj S Dilawar BA Malik BA Nawaz A Bhatti S 《Cell proliferation》2011,44(6):508-515
Prostate cancer is a serious molecular disorder that arises because of reduction in tumour suppressors and overexpression of oncogenes. The malignant cells survive within the context of a three-dimensional microenvironment in which they are exposed to mechanical and physical cues. These signals are, nonetheless, deregulated through perturbations to mechanotransduction, from the nanoscale level to the tissue level. Increasingly sophisticated interpretations have uncovered significant contributions of signal transduction cascades in governing prostate cancer progression. To dismantle the major determinants that lie beneath disruption of spatiotemporal patterns of activity, crosstalk between various signalling cascades and their opposing and promoting effects on TRAIL-mediated activities cannot be ruled out. It is important to focus on that molecular multiplicity of cancer cells, various phenotypes reflecting expression of a variety of target oncogenes, reversible to irreversible, exclusive, overlapping or linked, coexist and compete with each other. Comprehensive investigations into TRAIL-mediated mitochondrial dynamics will remain a worthwhile area for underlining causes of tumourigenesis and for unravelling interference options. 相似文献