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171.
Traditional herbal medicines such as Ferula gummosa Boiss. have been used for treatment of intestinal disorders in Iran. To date no pharmacological evidence for their effectiveness has been reported. The aim of this study was to examine the relaxant effect of essential oil, hydro-alcoholic, etheric, petrolic and methanolic extracts of Ferula gummosa and two of its components, alpha-pinene and beta-pinene, on isolated rat ileum contractions induced by KCl and acetylcholine (ACh). Ferula gummosa essential oil (FGEO) and hydro-alcoholic, etheric, petrolic and methanolic extracts all inhibited the response to 80 mM KCl in a concentration-dependent manner and attenuated the maximum attainable response of the ACh concentration-response curve. Although the effect of etheric extract on ACh contractions was less than that of petrolic extract, the overall order of effectiveness on the weight basis was the etheric, petrolic, methanolic, and hydro-alcoholic extracts, and the essential oil, respectively. A mixture of etheric and petrolic extracts together had a similar effect on KCl response to etheric extract was used alone. Alpha-pinene and beta-pinene both exhibited inhibitory effect on the contraction of rat ileum, but the inhibitory effect of beta-pinene on KCl contraction was more pronounced. The inhibitory effect of a mixture of these two compounds was, however, less than the sum of their separate effects. When a mixture of alpha-pinene and beta-pinene together were examined on the ileum, without presence of the spasmogen, they initially caused contraction of the tissue, while neither of them used alone caused a noticeable contraction of the ileum. This study shows that Ferula gummosa essential oil and its various extracts are relaxant of rat isolated ileum and that at least part of their inhibitory effect is due to alpha-pinene and beta-pinene components. As the inhibition of contractile over-activity of the ileum is the basis of the treatment of some gastero-intestinal disorders such as diarrhea, Ferula gummosa may have clinical benefits for treatment of this condition.  相似文献   
172.
Biology Bulletin - Light-emitting diodes (LEDs) can be used as a useful alternative to the in vitro culture of various plant species, which not only accelerates plantlet growth and development but...  相似文献   
173.
The assumption of Hardy-Weinberg equilibrium (HWE) among alleles in a nonevolving population is of fundamental importance in genetic studies. Deviation from HWE in a population usually indicates inbreeding, stratification and sometimes problems in genotyping. In populations of affected individuals, these deviations can also provide evidence for association. In this paper, we introduce a measure based on the Kullback-Leibler discrimination information function that quantifies the deviation from HWE in a population. We use this measure to order populations. We also propose a test for HWE based on an estimate of this measure. The test is a statistically consistent test of the null hypothesis for all alternatives and is very easy to implement. Our proposed test statistic is compared with an earlier, widely used, test. Finally, the use of the proposed new test is shown in an illustrative example.  相似文献   
174.
Mebudipine and dibudipine are two newly synthesized dihydropyridine (DHP) calcium channel blockers that have been shown to have considerable relaxant effects on vascular and atrial smooth muscle. The in vitro half-lives of mebudipine and dibudipine are reported to be significantly longer than that of nifedipine. In this study, we investigated the effects of mebudipine and dibudipine on voltage-activated Ca2+ channels on differentiated PC12 cells and compared their potencies to amlodipine. Our results point to absence of voltage-activated Ca2+ currents in undifferentiated PC12 cells. It is also concluded that mebudipine and dibudipine, like amlodipine are L-type calcium channel blockers. When tested in a range of 10-100 microM, mebudipine is at least as potent as amlodipine in inhibition of peak Ba2+ currents in differentiated PC12 cells while dibudipine is significantly less potent compared to amlodipine and mebudipine.  相似文献   
175.
Infectious bursal disease virus (IBDV) induces immunodeficiency in young chickens and apoptosis in chicken embryos. To understand the relation between the viral pathogenesis and the induction of cell death, chicken embryonic fibroblast (CEF) cells were infected with IBDV intermediate (im) and very virulent (vv) strains at different MOIs. The cell viability and DNA fragmentation were evaluated in infected cells. The cellular apoptotic pathway involve was investigated by determining the activities of caspase cascade. The imIBDV strain was replicated well in CEF cells and shown higher viral titers than vvIBDV. Apoptosis changes were observed only in vvIBDV-infected CEF cells at higher MOI 48 h post infection. Efflux of cytochrome c suggests that the intrinsic pathway of the apoptotic process induced by vvIBDV infection independently of virus replication. Prediction of caspase substrates cleavage sites revealed that different IBDV strains have conserved cleavage motif pattern for VP2 and VP5 viral proteins. These findings suggest the pathogenicity of IBDV strains might be involved in the induction of apoptosis in host cells.  相似文献   
176.
Psoriasis is a chronic inflammatory skin disease with an unknown aetiology that has been associated with abnormal plasma lipid metabolism and oxidative stress. There are controversial results in the previous studies investigating oxidant/antioxidant systems in psoriasis. The aim of this work was to evaluate the plasma levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), total bilirubin (T. Bili), direct bilirubin (D. Bili), uric acid (UA), apolipoproteins (ApoA1 and ApoB), Lp(a) and activities of paraxonase 1 (PON1) in 100 patients with psoriasis and 100 controls, and to look for a correlation between these parameters in psoriasis. PON1, bilirubin and UA were measured spectrophotometrically, MDA by the high‐performance liquid chromatography method, apolipoproteins and Lp(a) by immunoprecipitation assays, and lipid and other biochemical parameters were determined by routine laboratory methods. In patients with psoriasis, there was a significant decrease in PON1, SOD and CAT activities (P < 0.05) and an increase in MDA levels (P < 0.01). Also, the levels of bilirubin (total and direct) and UA were decreased in patients with psoriasis but were not significant (P > 0.05). These results suggest that psoriasis was in a state of oxidative stress and that the protective effects of high‐density lipoprotein against atherosclerosis may be dependent on PON1 activity. Moreover, there is a negative correlation between antioxidant with Lp(a), apoB and MDA levels, suggesting that subjects with higher levels of Lp(a) and apoB and lower levels of antioxidant are more exposed to oxidative damage. These findings may explain in part the reported increase in cardiovascular mortality in psoriasis. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
177.
The proliferation and differentiation characteristics of umbilical cord blood mononuclear cells were examined in a non-rotational suspension bioreactor with a fishtail mixer. The system consisted of a glass vessel, a mixer that moved vertically, a data acquisition and control system to continuously monitor pH, temperature and dissolved O2. The bioreactor provided superior expansion of total HSCs and not total cell number, as well as expression of stemness-related genes which followed with increasing in number of colony-forming cells during 14 days of culture compared to T -lask culture. Vertical agitation thus reduces the total cell number, which may be related to increased shear stress, but has no effect on HSC function.  相似文献   
178.
Tumor necrosis factor receptor 1 (TNFR1) is expressed on tumor cells and induces cell apoptosis through triggering proapoptotic cascade in these cells. Ago  相似文献   
179.
180.
Clostridium acetobutylicum is widely used for the microbial production of butanol in a process known as acetone–butanol–ethanol (ABE) fermentation. However, this process suffers from several disadvantages including high oxygen sensitivity of the bacterium which makes the process complicated and necessitate oxygen elimination in the culture medium. Nesterenkonia sp. strain F has attracted interests as the only known non-Clostridia microorganism with inherent capability of butanol production even in the presence of oxygen. This bacterium is not delimited by oxygen sensitivity, a challenge in butanol biosynthesis, but the butanol titer was far below Clostridia. In this study, Nesterenkonia sp. strain F was cocultivated with C. acetobutylicum to form a powerful “coculture” for butanol production thereby eliminating the need for oxygen removal before fermentation. The response surface method was used for obtaining optimal inoculation amount/time and media formulation. The highest yield, 0.31 g/g ABE (13.6 g/L butanol), was obtained by a coculture initiated with 1.5 mg/L Nesterenkonia sp. strain F and inoculated with 15 mg/L C. acetobutylicum after 1.5 hr in a medium containing 67 g/L glucose, 2.2 g/L yeast extract, 4 g/L peptone, and 1.4% (vol/vol) P2 solution. After butanol toxicity assessment, where Nesterenkonia sp. strain F showed no butanol toxicity, the coculture was implemented in a 2 L fermenter with continual aeration leading to 20 g/L ABE.  相似文献   
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