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991.
Applied Microbiology and Biotechnology - Due to the world’s dwindling energy supplies, greater thrust has been placed on the utilization of renewable resources for global succinate...  相似文献   
992.
Angelica polymorpha Maxim root extract (APRE) is a popular herbal medicine used for treating stomachache, abdominal pain, stomach ulcers, and rheumatism; however the effect of APRE on cancer cells has not yet been explored. Here, we examined APRE cytotoxicity seen on target neuroblastoma cells (NB) using cell viability assays, DAPI visualization of fragmented DNA, and Western blotting analysis of candidate signaling pathways involved in proliferation and apoptosis. We demonstrated that APRE reduced cell viability in NB to a greater extent than in fibroblast cells. In addition, we found that APRE could inhibit the three classes of MAPK proteins and could also down-regulate the PI3K/AKT/GSK-3β activity all being relevant for proliferation and survival. APRE could also up-regulate Bax expression and down-regulate Bcl-2 and Mcl-1. With APRE treatment, depolarization of mitochondria membrane potential and activation of caspase-3 was demonstrated in the SH-SY5Y cells. We could not found increased activity of death receptor and caspase-8 as markers of the extrinsic apoptosis pathway for the APRE treated cells. In presence of a caspase-3 siRNA and a pan-caspase inhibitor, APRE could not reduce the viability of NB cells to a significant degree. So we predicted that with APRE, the intrinsic pathway was solely responsible for inducing apoptosis as we also showed that the non-caspase autophagy pathway or ER stress-ROS mediated pathways were not involved. These findings demonstrate that an intrinsic mitochondria-mediated apoptosis pathway mediates the apoptotic effects of APRE on SH-SY5Y cells, and that APRE shows promise as a novel agent for neuroblastoma therapy.  相似文献   
993.
Present paper reports the effects of aqueous and ethanolic extracts of sugar cane (Saccharum officinarum L.) juice and bagasse, respectively on protective immune responses in industrial broiler chickens against coccidiosis. Immunotherapeutic efficacies of the extracts were measured by evaluating their effect on body weight gain, oocyst shedding, lesion score, anti-coccidial indices, per cent protection and elicited serum antibody responses against coccidiosis. Results revealed a significantly lower (P < 0.05) oocyst shedding and mortality in chickens administered with sugar cane extracts as compared to control. Further, significantly higher (P < 0.05) body weight gains and antibody responses were detected in chickens administered with sugar cane extracts as compared to chickens of control group. Moreover, ethanolic extract showed higher anti-coccidia index (227.61) as compared to aqueous extract (192.32). The organ body weight ratio of the lymphoid organs of experimental and control groups were statistically non-significant (P > 0.01). These results demonstrated that both ethanolic and aqueous extracts of sugar cane possess immune enhancing properties and their administration in chickens augments the protective immunity against coccidiosis.  相似文献   
994.
There has been a rapid decline of grassland bird species in the UK over the last four decades. In order to stem declines in biodiversity such as this, mitigation in the form of newly created habitat and restoration of degraded habitats is advocated in the UK biodiversity action plan. One potential restored habitat that could support a number of bird species is re-created grassland on restored landfill sites. However, this potential largely remains unexplored. In this study, birds were counted using point sampling on nine restored landfill sites in the East Midlands region of the UK during 2007 and 2008. The effects of restoration were investigated by examining bird species composition, richness, and abundance in relation to habitat and landscape structure on the landfill sites in comparison to paired reference sites of existing wildlife value. Twelve bird species were found in total and species richness and abundance on restored landfill sites was found to be higher than that of reference sites. Restored landfill sites support both common grassland bird species and also UK Red List bird species such as skylark Alauda arvensis, grey partridge Perdix perdix, lapwing Vanellus vanellus, tree sparrow, Passer montanus, and starling Sturnus vulgaris. Size of the site, percentage of bare soil and amount of adjacent hedgerow were found to be the most influential habitat quality factors for the distribution of most bird species. Presence of open habitat and crop land in the surrounding landscape were also found to have an effect on bird species composition. Management of restored landfill sites should be targeted towards UK Red List bird species since such sites could potentially play a significant role in biodiversity action planning.  相似文献   
995.
The current study evaluated the possible toxic effects of the water-soluble fraction of crude oil on the general cellular stress-response mechanisms of two dominant representatives of Lake Baikal’s littoral community, the endemic amphipod species Eulimnogammarus verrucosus and E. cyaneus. The acute toxicity effects on the cellular stress-response mechanisms of amphipods were studied in the laboratory by exposing amphipods in water from Lake Baikal to addition of a water-soluble fraction of crude oil at concentrations considered safe for the aquatic environment. The present study found that even short-term exposure to a water-soluble fraction of crude oil at concentration of 50 µg/L, established as the threshold limit for fishery and aquaculture water reservoirs in the Russian Federation, directly affected the general stress-response markers HSP70 and lipid peroxidation and significantly changed the activity of antioxidant enzymes in both studied species. This result confirms the high sensitivity of Baikal endemics to crude oil. Thus, it also indicates that established standards and threshold limit values of oil concentrations estimated for ecological monitoring of general water reservoirs cannot be applied directly to the unique Lake Baikal ecosystem.  相似文献   
996.
Sunitinib malate (SM) is reported as a weakly soluble drug in water due to its poor dissolution rate and oral bioavailability. Hence, in the current study, various “self-nanoemulsifying drug delivery systems (SNEDDS)” of SM were prepared, characterized and evaluated for the enhancement of its in vitro dissolution rate and anticancer efficacy. On the basis of solubilization potential of SM in various excipients, “Lauroglycol-90 (oil), Triton-X100 (surfactant) and Transcutol-P (cosurfactant)” were selected for the preparation of SM SNEDDS. SM-loaded SNEDDS were developed by spontaneous emulsification method, characterized and evaluated for “thermodynamic stability, self-nanoemulsification efficiency, droplet size, polydispersity index (PDI), zeta potential (ZP), surface morphology, refractive index (RI), the percent of transmittance (% T) and drug release profile.” In vitro dissolution rate of SM was significantly enhanced from an optimized SNEDDS in comparison with SM suspension. The optimized SNEDDS of SM with droplet size of 42.3 nm, PDI value of 0.174, ZP value of ?36.4 mV, RI value of 1.339, % T value of 97.3%, and drug release profile of 95.4% (after 24 h via dialysis membrane) was selected for in vitro anticancer efficacy in human colon cancer cells (HT-29) by MTT assay. MTT assay indicated significant anticancer efficacy of optimized SM SNEDDS against HT-29 cells in comparison with free SM. The results of this study showed the great potential of SNEDDS in the enhancement of in vitro dissolution rate and anticancer efficacy of poorly soluble drug such as SM.  相似文献   
997.
Iranian population with an Indo-European origin is one of the oldest populations in the world. Historical evidence suggests the close similarity in the origin of Iranian, European and north Indian population. However, there are few anthropological and genetic evidences on this subject. This study, which is the first report from Iran, was performed to investigate the genetic origin of Iranian population using a polymorphism in Cystathionine beta synthase (CBS) gene known as 844INS68bp in this respect, genomic DNA was extracted from the whole blood of 480 healthy normal blood donors referred to Fars Blood Transfusion Center, using a salting out method. The fragment containing 844INS68bp was amplified, the normal fragment was 174 bp and the fragment containing the insertion was 242 bp in length. Results indicated that 418 (87.08%) out of 480 individuals had a normal (N/N) genotype, 59 (12.29%) individuals were heterozygote (N/I) and 3 (0.63%) had homozygote a mutated genotype (I/I). The total frequency of 844INS68bp allele was found 6.8% which is similar to with the reported in White Caucasians. Comparison of the genotype of this study with the polymorphism in other populations revealed that Southern Iranian population has a great similarity with other Caucasians populations’ especially South Italy and North America while differed from East Asian and African populations. These results are in agreement with the result of other studied polymorphisms. Therefore, despite the great admixture of Iranian population with the neighboring non-Caucasian populations during the time, Iranian population still share a genetic background with other Caucasian populations.  相似文献   
998.
999.
Modulation of differential gene expression and change of polyamine content by salt stress are analyzed for the first time in a well-known medicinal plant, Panax ginseng C.A. Meyer. Three ginseng genes (PgSPD, PgSAMDC, and PgADC) involved in polyamine biosynthesis showed differential up-regulation patterns after 1 and 7 days of salt treatments. The modulation of gene expression resulted in the elevation of total polyamine content with relatively high levels of spermidine and spermine, while putrescine level diminished depending on the salt concentration. Conversely, salt stress led to a significant increase in diamine oxidase and subsequent decline in polyamine oxidase. The proline content caused by salinity follows a similar pattern as the total polyamine content and exogenous spermidine also resulted in the alleviation of proline content under salinity. Further, polyamine biosynthesis inhibitors, such as cyclohexylamine and methylglyoxal bis-(guanylhydrazone) mediated down-regulation of PgSPD and PgSAMDC, and affected cellular polyamine levels. Thus, polyamines may enhance the ginseng plant tolerance in response to the salt stress by increasing the levels of endogenous polyamines.  相似文献   
1000.
The increasing global demand for biomass of medicinal plant resources reflects the issues and crisis created by diminishing renewable resources and increasing consumer populations. Moreover, diverse usage of plants and reduced land for cultivation in the world accelerated the deficiency of plant resources. In addition, the preparation of safety of plant based medicine whips up demand for biomass of valuable medicinal plants. As one of alternative approach to upswing the productivity of plant-based pharmaceutical compounds, automation of adventitious root culture system in air-lift bioreactor was adopted to produce cosmic amount of root biomass along with enriched diverse bioactive molecules. In this review, various physiological, engineering parameters, and selection of proper cultivation strategy (fed-batch, two-stage etc.) affecting the biomass production and secondary metabolite accumulation have been discussed. In addition, advances in adventitious root cultures including factors for process scale-up as well as recent research aimed at maximizing automation of the bioreactor production processes are also highlighted. Examples of the scale-up of cultures of adventitious roots of Morinda citrifolia, Echinacea purpurea and angustifolia, Hypericum perforatum and Panax ginseng by applying 20L to 10,000L bioreactors in our lab were demonstrated with a view of commercial application.  相似文献   
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