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121.
Gene transfer into cultured chondrocytes by using adenoviral vectors has potential applications in treating cartilage disorders. The present study was undertaken to compare and optimize two chondrocyte culture conditions for adenoviral transduction efficacy by using primary human articular chondrocytes cultivated either directly in a monolayer condition or as outgrowths from alginate-stored chondrocyte cultures. Isolated primary chondrocytes from human articular cartilage were either immediately transduced with an EGFP (enhanced green fluorescent protein)-gene-bearing adenoviral vector (1,000 and 3,000 virus particles/cell) or cultured in alginate before transduction. Immunohistochemistry and flow cytometric analysis were employed to determine the expression of extracellular matrix proteins and of the αvβ5 integrin receptor involved in adenoviral cell entry. Monolayer chondrocytes exhibited moderate transduction rates (mean 22.2% and 46.9% EGFP-positive cells at 1,000 and 3,000 virus particles/cell by 72 h post-transduction), whereas alginate-derived chondrocytes revealed significantly higher transduction efficacies (95.7% and 99%). Both monolayer and alginate-derived chondrocytes expressed αvβ5 integrin, type II collagen and cartilage proteoglycans. The mean fluorescence intensity of type II collagen was significantly higher in the alginate-derived chondrocytes, whereas that of αvβ5 integrin was higher in the monolayer chondrocytes. Our results indicate that transduction efficacy is independent of αvβ5 integrin expression levels in chondrocytes. Moreover, adenoviral transduction of alginate-derived chondrocytes is more efficient than that for monolayer chondrocytes and may be a suitable tool to achieve sufficient numbers of transduced and differentiated chondrocytes for experimental applications and cartilage repair. Dr. Gundula Schulze-Tanzil is supported by a grant awarded by the Rahel Hirsh Foundation from the Charité Medical Schools Berlin. The study was supported by a grant from the Deutsche Arthrosehilfe e.V.  相似文献   
122.
Establishment and maintenance of transgenic mouse strains require being able to distinguish homozygous from heterozygous animals. To date, the developed real-time quantitative PCR techniques are often complicated, time-consuming and expensive. Here, we propose a very easy and rapid method with a simple data analysis to determine zygosity in transgenic mice. We show that the real-time quantitative PCR using SYBR Green fluorescent dye can be applied to discriminate two-fold differences in copy numbers of the transgene. Our procedure has to fit only three simple requirements: (1) to design primers capable of detecting one Ct difference for two-fold differences in DNA amounts (2) to measure genomic DNA concentrations accurately and (3) to have a reference animal of known zygosity in each run. Then, if the Ct values for the control gene are similar in all samples, we are able to compare directly the Ct values for the transgene in every sample, and so, to deduce the zygosity status of each mouse relative to the reference animal. This method is really simple and reliable, and it may be valuable as a rapid screening tool for zygosity status in transgenic animals.  相似文献   
123.
Catalysis is the key technology for the development of green processes for the industrial production of active pharmaceutical ingredients. The design of green, efficient and cost competitive industrial process of idarubicin, erlotinib and ivermectin shows the central role of catalysis.
Riassunto   La catalisi: tecnologia fondamentale per it design di processi industriali a basso impatto ambientale nell'industria farmaceutica. La catalisi è la tecnologia fondamentale per lo sviluppo di processi industriali ?green?, efficienti e a basso costo per la produzione di idarubicina, erlotinib e ivermectina, dimostra il ruolo centrale dei processi catalitici.
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124.
Quantitative surveys of the chrysopid fauna from southwestern Europe, namely the Iberian and Italian peninsulas, France south of 46° N, and the west-Mediterranean Islands, were analysed. A total of 56 species of Chrysopidae were reported, of which three species were abundant. These, Chrysoperla carnea (Stephens, 1836) sensu lato, Dichochrysa prasina (Burmeister, 1839) and D. flavifrons (Brauer, 1850), comprised a large percentage of the specimens. For the rarer species, comments are made on their distributions, the enhanced geographic range of exotic ones, and on levels of endemism and stenotopy.  相似文献   
125.
Intestine absorption of intact green fluorescent protein (GFP) and its following accumulation in the renal proximal tubule cells after its intragastric administration have been established by confocal microscopy in the rat and frog. Reabsorbed GFP was revealed in the endosomes and lysosomes of the proximal tubule cells by the methods of GFP photooxidation and immunofluorescent microscopy. The GFP intestine absorption rate and GFP accumulation in the kidney were significantly higher in the frog than in the rat. No specific fluorescence was revealed in the liver and colon cells after the GFP intragastric administration. The data obtained indicate the ability of the small intestine in the frog and rat to absorb intact proteins and an important role of the kidney in exogenous protein metabolism.  相似文献   
126.
We demonstrate that the tea polyphenol, epigallocatechin-3-gallate, is an efficient inhibitor of human dihydrofolate reductase. Like other antifolate compounds, epigallocatechin-3-gallate acts by disturbing folic acid metabolism in cells, causing the inhibition of DNA and RNA synthesis and altering DNA methylation. Epigallocatechin-3-gallate was seen to inhibit the growth of a human colon carcinoma cell line in a concentration and time dependent manner. Rescue experiments using leucovorin and hypoxanthine–thymine medium were the first indication that epigallocatechin-3-gallate could disturb the folate metabolism within cells. Epigallocatechin-3-gallate increased the uptake of [3H]-thymidine and showed synergy with 5-fluorouracil, while its inhibitory action was strengthened after treatment with hypoxanthine, which indicates that epigallocatechin-3-gallate decreases the cellular production of nucleotides, thus, disturbing DNA and RNA synthesis. In addition to its effects on nucleotide biosynthesis, antifolate treatment has been linked to a decrease in cellular methylation. Here, we observed that epigallocatechin-3-gallate altered the p16 methylation pattern from methylated to unmethylated as a result of folic acid deprivation. Finally, we demonstrate that epigallocatechin-3-gallate causes adenosine to be released from the cells because it disrupts the purine metabolism. By binding to its specific receptors, adenosine can modulate different signalling pathways. This proposed mechanism should help us to understand most of the molecular and cellular effects described for this tea polyphenol.  相似文献   
127.
Potato is one of the main targets for genetic improvement by gene transfer. The aim of the present study was to establish a robust protocol for the genetic transformation of three dihaploid and four economically important cultivars of potato using Agrobacterium tumefaciens carrying the in vivo screenable reporter gene for green fluorescent protein (gfp) and the marker gene for neomycin phosphotransferase (nptII). Stem and leaf explants were used for transformation by Agrobacterium tumefaciens strain LBA4404 carrying the binary vector pHB2892. Kanamycin selection, visual screening of GFP by epifluorescent microscopy, PCR amplification of nptII and gfp genes, as well as RT-PCR and Southern blotting of gfp and Northern blotting of nptII, were used for transgenic plant selection, identification and analysis. Genetic transformation was optimized for the best performing genotypes with a mean number of shoots expressing gfp per explant of 13 and 2 (dihaploid line 178/10 and cv. ‘Baltica’, respectively). The nptII marker and gfp reporter genes permitted selection and excellent visual screening of transgenic tissues and plants. They also revealed the effects of antibiotic selection on organogenesis and transformation frequency, and the identification of escapes and chimeras in all potato genotypes. Silencing of the gfp transgene that may represent site-specific inactivation during cell differentiation, occurred in some transgenic shoots of tetraploid cultivars and in specific chimeric clones of the dihaploid line 178/10. The regeneration of escapes could be attributed to either the protection of non-transformed cells by neighbouring transgenic cells, or the persistence of Agrobacterium cells in plant tissues after co-cultivation.  相似文献   
128.
《Cryobiology》2015,70(3):500-502
We investigated the effect of storage times of frozen–thawed Persian sturgeon (Acipenser persicus) semen on the duration of sperm motility, percentage of motile sperm, and fertilization and hatching rates of fresh sperm and sperm stored for 0, 30, and 60 min at 4 °C post-thawing. Frozen thawed semen analyzed immediately after thawing had similar quality characteristics as fresh semen. For cryopreserved semen stored for 30 min after thawing the characteristics did not differ to fresh semen and cryopreserved semen. For cryopreserved semen stored for 60 min a significant decline in the parameters was observed. Fertilization and hatching rates were not affected by storage times of maximally 30 min of storage.  相似文献   
129.
Environmentally sustainable activities have received an increasing interest among the firms to improve their practices in the supply chain. Although environmental regulations force firms consider these issues, but, green issues are new, evolving every day, and requires a continuous study in the field to gain a complete understanding of the problems. In this study, we illustrate the case of a laptop manufacturer in Malaysia that pursues to evaluate green supply chain management (GSCM) indicators among its practitioners. This paper develops a quantitative evaluation model to measure the uncertainty of GSCM activities and applies an approach based on Vlsekriterijumska Optimizacija I Kompromisno Resenje (VIKOR) method which is an extension of intuitionistic fuzzy environment aiming to solve the green multi-criteria decision making (GMCDM) problem. The triangular fuzzy numbers (TFNs) were used to handle imprecise numerical quantities. Then, a hierarchical multiple criteria decision making (MCDM) model was proposed based on fuzzy sets theory and VIKOR method to deal with the problem. The results show the alternative ranks of the four evaluated companies which was based on their performance in GSCM initiatives. The results also indicated that the main criteria of the research ranked as follows respectively: eco-design, green production, green purchasing, green recycling, green transportation and green warehousing. Finally, a comparative analysis of results by fuzzy VIKOR is presented. Additionally the scope for future studies is provided at the end of the paper.  相似文献   
130.
Endophytic fungi belonging to the genus Gliocladium are able to degrade plant cellulose and synthesize complex hydrocarbons under microaerophilic conditions. These fungi could thus be used to produce biofuels from cellulosics without the need for hydrolytic pretreatments. Gas chromatography-mass spectrometry-solid-phase micro-extraction (GC-MS-SPME) of head space gases from Gliocladium cultures demonstrated the production of C(6)-C(19) hydrocarbons including hexane, benzene, heptane, 3,4-dimethyl hexane, 1-octene, m-xylene, 3-methyl nonane, dodecane, tridecane, hexadecane and nonadecane directly from the cellulosic biomass. Hydrocarbon production was 100-fold higher in co-cultures of Gliocladium and Escherichia coli than in pure Gliocladium cultures. The dry mycelia weight is stable at stationary period in co-culture condition which may lead to synthesize more hydrocarbons. These fungi could potentially be developed into cost-effective biocatalysts for production of biofuels.  相似文献   
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