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The potential of TRAIL for cancer chemotherapy   总被引:5,自引:0,他引:5  
Innate and acquired resistance to chemotherapy and radiation therapy has been a major obstacle for clinical oncology. One potential adjunct to such conventional treatments is direct induction of cell death by activation of death receptor-mediated apoptosis. TRAIL (tumor necrosis factor (TNF)-related apoptosis inducing ligand), a recently identified member of the growing TNF superfamily, binds to its cognate death receptors DR4 and DR5 as well as decoy receptors DcR1 and DcR2. Upon binding, rapid apoptosis is enacted in a variety of human cancer cell lines independent of p53 status, but not in normal cell lines. TRAIL treatment results in significant growth suppression of TRAIL-sensitive human cancer xenografts in mice. Furthermore, combination treatment of TRAIL with genotoxic chemotherapeutic agents synergistically suppresses growth of tumor xenografts which are otherwise resistant to treatment with TRAIL or chemotherapy alone. Unlike the other death ligands TNF- or FasL, systemic administration of soluble human TRAIL does not cause toxicity in mice and non-human primates. While further studies are needed to evaluate the possible cytotoxicity of TRAIL especially for human hepatocytes, indications are increasing that TRAIL may be a novel therapeutic agent for human cancer.  相似文献   

3.
《Autophagy》2013,9(7):950-951
In macroautophagy (hereafter autophagy), a morphological hallmark is the formation of double-membrane vesicles called autophagosomes that sequester and deliver cytoplasmic components to the lysosome/vacuole for degradation. This process begins with an initial sequestering compartment, the phagophore, which expands into the mature autophagosome. A tremendous amount of work has been carried out to elucidate the mechanism of how the autophagosome is formed. However, an important missing piece in this puzzle is where the membrane comes from. Independent lines of evidence have shown that pre-existing organelles may continuously supply lipids to support autophagosome formation. In our analysis, we identified several components of the late stage secretory pathway that may redirect Golgi-derived membrane to autophagosome formation in response to starvation conditions.  相似文献   

4.
In macroautophagy (hereafter autophagy), a morphological hallmark is the formation of double-membrane vesicles called autophagosomes that sequester and deliver cytoplasmic components to the lysosome/vacuole for degradation. This process begins with an initial sequestering compartment, the phagophore, which expands into the mature autophagosome. A tremendous amount of work has been carried out to elucidate the mechanism of how the autophagosome is formed. However, an important missing piece in this puzzle is where the membrane comes from. Independent lines of evidence have shown that preexisting organelles may continuously supply lipids to support autophagosome formation. In our analysis, we identified several components of the late stage secretory pathway that may redirect Golgi-derived membrane to autophagosome formation in response to starvation conditions.Key words: lysosome, membrane biogenesis, protein targeting, secretory pathway, stress, vacuole, yeast  相似文献   

5.
Axl tyrosine kinase has been shown to be involved in multiple pathways contributing to tumor development, angiogenesis, and metastasis. High Axl expression has been observed in many human tumors where it appears to confer aggressive tumor behavior. Here we present several series of dual Axl-VEGF-R2 kinase inhibitors based on extensive optimization of an acyl diaminotriazole. It was hypothesized that dual inhibition of these two receptor tyrosine kinases may have a synergistic affect in inhibiting tumor angiogenesis and metastasis. One of these molecules, R916562 showed comparable activity to Sunitinib in two mouse tumor xenograft models and a mouse corneal micropocket model.  相似文献   

6.
A method for obtaining phospholipids from butter-milk, a by-product of butter making is described. The method consists in coagulating the fat globule membranes with mineral or organic acid, separating the resulted precipitate by centrifugation or filtering, lipid extraction by organic solvents mixture and isolation of phospholipids from the extract by acetone treatment or by column chromatography. Butter-milk, a new source of biological membranes, is characterized by a low cost and accessibility.  相似文献   

7.
Prolific algal growth in sewage ponds with high organic loads in the tropical regions can provide cost-effective and efficient wastewater treatment and biofuel production. This work examines the ability of Euglena sp. growing in wastewater ponds for biofuel production and treatment of wastewater. The algae were isolated from the sewage treatment plants and were tested for their nutrient removal capability. Compared to other algae, Euglena sp. showed faster growth rates with high biomass density at elevated concentrations of ammonium nitrogen (NH4-N) and organic carbon (C). Profuse growth of these species was observed in untreated wastewaters with a mean specific growth rate (μ) of 0.28 day?1 and biomass productivities of 132 mg ?L?1? day?1. The algae cultured within a short period of 8 days resulted in the 98 % removal of NH4-N, 93 % of total nitrogen 85 % of ortho-phosphate, 66 % of total phosphate and 92 % total organic carbon. Euglenoids achieved a maximum lipid content of 24.6 % (w/w) with a biomass density of 1.24 g ?L?1 (dry wt.). Fourier transform infrared spectra showed clear transitions in biochemical compositions with increased lipid/protein ratio at the end of the culture. Gas chromatography and mass spectrometry indicated the presence of high contents of palmitic, linolenic and linoleic acids (46, 23 and 22 %, respectively), adding to the biodiesel quality. Good lipid content (comprised quality fatty acids), efficient nutrient uptake and profuse biomass productivity make the Euglena sp. as a viable source for biofuel production in wastewaters.  相似文献   

8.

Introduction

Anabolic steroids are frequently misused for performance enhancement during sports competitions. One of the major bottlenecks in the confident analysis of steroids and their metabolites is the non-availability/cost of standard reference compounds.

Objective

The study objective was to identify the common metabolites of prohibited anabolic steroids that are produced in both fungi and human and thus can be synthesized in bulk using fungal cultures. Mesterolone is used as a case study.

Methods

The study was conducted in three steps; we first studied the fungal transformation of mesterolone. In the second step, these metabolites were used as references to detect in human urine after the oral use of mesterolone using LC-ESI-QqQ-MS/MS. In the third step, 12 fungal cultures were screened to evaluate their potential to produce reference markers.

Results

This led to the detection of two metabolites, 6α-hydroxymesterolone (M1) and 7α-hydroxymesterolone (M2) that were found to be common in both, fungal cultures and human urine samples. Moreover, Rhizopus stolonifer and Beauveria bassiana can be considered as good candidates to produce M1 and M2 metabolites, respectively.

Conclusion

This approach can be employed for the synthesis of marker compounds of other prohibited anabolic steroids thus can be detected efficiently during national and international sports competitions.
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9.
Aims: To screen 19 strains of bifidobacteria for main folate forms composition in synthetic folate‐free and complex folate‐containing media. Methods and Results: HPLC was used to analyse deconjugated folates extracted from bacterial biomass. Most strains had a total folate content above 4000 μg per 100 g dry matter (DM). The highest value of 9295 μg per 100 g DM was found in Bifidobacterium catenulatum ATCC 27539 and the lowest in Bifidobacterium animalis ssp. animalis ATCC 25527 containing 220 μg per 100 g DM. Ten strains grew in a synthetic folate‐free medium (FFM), showing folate autotrophy and suggesting folate auxotrophy of the remaining nine. In the autotrophic strains, a consistently higher folate level was found in FFM as compared to a more complex folate‐containing medium, suggesting reduced requirements for folates in the presence of growth factors otherwise requiring folates for synthesis. The contents of total folate, 5‐CH3‐H4folate and H4folate were strain dependent. 5‐CH3‐H4folate dominated in most strains. Conclusions: Our results show that bifidobacteria folate content and composition is dynamic, is strain specific and depends on the medium. Suitable selection of the growth conditions can result in high levels of folate per cell unit biomass. Significance and Impact of the Study: This suggests that certain bifidobacteria may contribute to the folate intake, either directly in foods, such as fermented dairy products, or in the intestine as folate‐trophic probiotics or part of the natural microbiota.  相似文献   

10.
The aim of this work was to estimate the trypsin inhibitor activity (TIA) in seeds of cultivated pea varieties, wild varieties and selected crosses between varieties from the first group and wild pea varieties and to study the variation in genes coding trypsin inhibitors. Mean TIA in field pea varieties ranged from 3.12 TIU/mg of sample in field pea variety from Czech Republic to 12.90 TIU/mg of sample in field pea variety FP S4 of Serbian origin. Wild field pea varieties showed TIA between 0.98 TIU/mg of sample in Pisum elatius and 9.79 TIU/mg of sample in Pisum abyssinicum. Selected crosses between cultivated field pea varieties and Pisum elatius showed a decrease in TIA in comparison with a parent line that has higher TIA content. The PCR amplification resulted in variety-specific amplification. Varieties with low TIA activity showed amplification with At13/At5 primer pair, while varieties with higher TIA activity showed amplification with primer pairs At12/At5, At14/At5 and At14/At8. Thus, At13/At5 primer pair could be sufficient to distinguish most varieties. These markers can be applied during an early screening of the valuable materials for future breeding programs of pea cultivars with the low level of tripsin inhibitor.  相似文献   

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It is known that seaweeds differ greatly from land plants in their sugar composition. The current research on the L-lactic acid fermentation process focuses on land plant sugars as a carbon source, with the potential of seaweed sugars being largely ignored. This study examined the feasibility of seaweed biomass as a possible carbon source for the production of l-lactic acid, by comparing the fermentation of seaweed sugars (d-galactose, d-mannitol, l-rhamnose, d-glucuronic acid, and l-fucose) and land plant sugars (d-glucose, d-xylose, d-mannose, and l-arabinose). The experiments were repeated with 2 sugar acids (d-gluconic acid, d-glucaric acid) in order to investigate the effect of the degree of reduction of carbon source on the fermentation yield. This research also examined the effect of bacterial strain on the characteristics of fermentation reactions, by conducting l-lactic acid fermentation with 7 different Lactobacillus species. Taking into account the sugar composition of seaweed and the levels of lactic acid production from each pure sugar, it was possible to predict the lactic acid production yield of various seaweeds and land plants. From comparative analysis of the predicted lactic acid production yield, it was found that seaweeds are already comparable to lignocellulosics at the current stage of technology. If new technologies for the utilization of non-fermentable seaweed sugars are developed, seaweeds show promise as an even more useful biomass feedstock than lignocellulosics.  相似文献   

13.
This study was designed to assess the value of seaweeds from the Galician coast as a source of minerals (especially iodine (I) but also other micro-minerals) in organic dairy cattle. It was conducted in an organic dairy farm in the Lugo province that typically represents the organic milk production in NW Spain. The animal’s diet consisted mainly of local forage (at pasture or as hay and silage in the winter) and 5 kg of purchased concentrate/day per animal (representing 23.5% of feed intake). Based on the mineral composition of the diet, the physiological requirements and the EU maximum authorised levels in feed, a supplement composed by Sea Lettuce (Ulva rigida) (as flakes, 80%), Japanese Wireweed (Sargasum muticum) (flakes, 17.5%) and Furbelows (Saccorhiza polyschides) (powder, 2.5%) was formulated to give 100 g/animal per day. Sixteen Holstein Friesian lactating cows were randomly selected and assigned to the control (n=8) and algae-supplemented groups (n=8). Both groups had exactly the same feeding and management with the exception of the algae supplement, which was mixed with the concentrate feed and given to the animals at their morning milking for 10 weeks. Heparinised blood (for plasma analysis) and milk samples were collected at 2-week intervals and analysed for toxic and trace element concentrations by inductively coupled plasma-mass spectrometry or inductively coupled plasma-optical emission spectrometry. The algae supplement significantly improved the animals’ mineral status, particularly I and selenium that were low on the farm. However, the effect of the algae supplement on the molybdenum status in cattle needs further investigation because of its great relevance on copper metabolism in ruminants. The I supply deserves special attention, since this element is at a very high concentration in brown-algae species and it is excreted in the milk proportionally to its concentration in plasma concentrations (mean±s.e. in the algae-supplemented and control groups were 268±54 and 180±42 µg/l, respectively).  相似文献   

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Summary White clover (Trifolium repens) growing in association with grasses on colliery spoil amended with lime and complete fertilizer proved to be an effective nitrogen source for the developing ecosystem. Nitrogen transfer from the clover to an associated grass became aparent within 22 months of sowing.  相似文献   

16.
The prevalence of allergic diseases such as asthma, atopic dermatitis, and allergic rhinitis has increased during the last two decades and contributed a great deal to morbidity and an appreciable mortality in the world. Until now, few novel efficacious drugs have been discovered to treat, control or even cure these diseases with a low adverse-effect profile. Meanwhile, glucocorticoids are still the mainstay for the treatment of allergic disease. Therefore, it is necessary to isolate novel anti-allergic agents from natural resources. Recently, marine algae have received much attention as they are a valuable source of chemically diverse bioactive compounds with numerous health benefit effects. This review focuses on anti-allergic agents derived from marine algae and presents an overview of their pharmaceutical potential in the treatment of allergic disorders.  相似文献   

17.
As a result of high production costs, commercial products from microalgae must command high prices. Astaxanthin produced by Haematococcus is a product that has become a commercial reality through novel and advanced technology. Cultivation methods have been developed to produce Haematococcus containing 1.5-3.0% astaxanthin by dry weight, with potential applications as a pigment source in aquaculture, poultry feeds and in the worldwide nutraceutical market.  相似文献   

18.
The surfaces of marine eukaryotes provide a unique habitat for colonizing microorganisms where competition between members of these communities and chemically mediated interactions with their host are thought to influence both microbial diversity and function. For example, it is believed that marine eukaryotes may use their surface-associated bacteria to produce bioactive compounds in defence against competition and to protect the host against further colonization. With the increasing need for novel drug discovery, marine epibiotic bacteria may thus represent a largely underexplored source of new antimicrobial compounds. In the current study, 325 bacterial isolates were obtained from the surfaces of marine algae Delisea pulchra and Ulva australis . Thirty-nine showed to have antimicrobial activity and were identified via 16S rRNA gene sequencing. The majority of those isolates belonged to Alpha- and Gammaproteobacteria . Interestingly, the most commonly isolated bacterial strain, Microbulbifer sp., from the surface of D. pulchra has previously been described as an ecologically significant epibiont of different marine eukaryotes. Other antimicrobial isolates obtained in this study belonged to the phyla Actinobacteria , Firmicutes and Bacteroidetes . Phylogenetically, little overlap was observed among the bacteria obtained from surfaces of D. pulchra and U. australis . The high abundance of cultured isolates that produce antimicrobials suggest that culturing remains a powerful resource for exploring novel bioactives of bacterial origin.  相似文献   

19.
The aquarium trade has been identified as an important vector of aquatic invasive species but this question has mostly been investigated in North America. We investigated the variation in diversity and species composition in different trade types in southwestern Europe (three major international wholesalers, different retail store types, and local internet forums), mostly in Spain and Portugal. As in previous studies, the diversity of fishes in the aquarium trade was vast, with a total of 20 orders, 79 families, and 1,133 fish species detected in the trade types analyzed. 248 species were observed in a single metropolitan area (Barcelona), with estimates of about 294 species being present. International wholesalers had higher species richness and evenness, with a single one having over 700 species. General pet stores had much lower evenness but due to high turnover had a total richness of over 200 species. Internet forums had the lowest evenness but similar richness. The different commerce types varied significantly in relative species abundance with about a dozen of popular fish species (e.g., goldfish, Siamese fighting fish, common carp, guppy, swordtails) dominating the retail stores, particularly the general pet stores. Our results imply that frequency in the trade varies strongly among species and commerce types and although general pet stores have usually low diversity, this is compensated with a higher species turnover. Many of the most popular species are well known invasive species and some of the species available are temperate species that might establish in Europe, reinforcing the need for more careful implementation of education programs, regulation and monitoring of trade, and internalization of environmental costs by the industry.  相似文献   

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