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161.
The tomato processing industry generates large quantities of tomato peel residues, usually creating environmental problems. These residues are a significant source of lycopene, thus providing an attractive alternative for profitable handling of these otherwise problematic by-products. The enzymatic pretreatment of these residues for lycopene recovery has already been employed, although the use of surfactants for enhancing the recovery has not been examined so far. The enzymatic pretreatment of tomato peels, using two commercially available pectinolytic enzyme preparations, was evaluated suggesting that there is an optimum pretreatment time of about 1 h, enzyme amount 250 Units/mL and no significant pH influence. Lycopene surfactant - assisted extraction was further investigated, showing that, among eight surfactants used, the most suitable was "Span 20", with an optimum ratio of 6-7 surfactant molecules per lycopene molecule. Sequential enzymatic pretreatment and surfactant-assisted extraction (30 min for each step) was evaluated leading to an improved lycopene extraction yield, with a somewhat smaller surfactant molar ratio (i.e. 4-5). In the latter case, the yield of lycopene recovery was almost four times greater compared to just 1 hr enzymatic pretreatment, and was approximately ten times greater compared to the recovery from untreated peels. Furthermore, such lipophilic compound recovery, avoiding the use of organic solvents, is environmentally attractive and ensures direct lycopene use in the food and cosmetics industries. 相似文献
162.
Andreadou M Liandris E Kasampalidis IN Taka S Antoniou M Ntais P Vaiopoulou A Theodoropoulos G Gazouli M Ikonomopoulos J 《Experimental parasitology》2012,131(4):419-424
Protozoa of the genus Leishmania are the causative agents of leishmaniosis. Although the polymerase chain reaction (PCR) has proved very effective in the detection of Leishmania DNA, a standardized method does not exist. In this study we attempt a comparative evaluation between one real time PCR (Method D), two in-house (Methods A and C), and a commercially available PCR assay (Method B) for the detection of Leishmania DNA, in order to support reliable diagnostic investigation of leishmaniosis. This evaluation was performed in regard to relative specificity and sensitivity, minimum detection limit (MDL), repeatability and reproducibility using cultured isolates and clinical samples. All the methods under study produced the expected result with the positive and negative controls. However with regard to clinical samples, Method C showed a statistically significant higher level of positivity. Relative sensitivity and specificity of Methods A, B and D in comparison to C was calculated respectively at 50.7%, 43%, 40%, and 90.8%, 93.4% and 89.5%. The MDL for Methods A-D was defined respectively at 30.7, 5, 3.7, and 5 promastigotes/ml. Repeatability and reproducibility were excellent in all cases with only the exception of Method A regarding reproducibility with a different brand of PCR reagents. The results that were recorded indicate that evaluation of PCR assays before their application for research and clinical diagnosis can provide useful evidence for their reliable application. Within this context the use of internal amplification controls and the confirmation of the specificity of the amplification product is recommended. 相似文献
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164.
Angiogenesis is tightly regulated by numerous endogenous pro- and anti-angiogenic proteins and peptides. Among these are the CXC chemokines, a set of multifunctional peptides. CXC chemokines containing the ELR motif act as pro-angiogenic agents by regulating both endothelial cell proliferation and migration. Here we show that a set of six 22-24-amino acid peptides derived from the pro-angiogenic ELR-containing CXC chemokines exhibit notable anti-proliferative and anti-migratory activity in vitro; we call these peptides chemokinostatins. The ability of the identified peptides to inhibit the basic components of angiogenesis even though they are derived from pro-angiogenic proteins contributes towards the understanding of the diverse role of the CXC chemokine family in angiogenesis. 相似文献
165.
Genetic Analysis of Human Traits In Vitro: Drug Response and Gene Expression in Lymphoblastoid Cell Lines 下载免费PDF全文
Edwin Choy Roman Yelensky Sasha Bonakdar Robert M. Plenge Richa Saxena Philip L. De Jager Stanley Y. Shaw Cara S. Wolfish Jacqueline M. Slavik Chris Cotsapas Manuel Rivas Emmanouil T. Dermitzakis Ellen Cahir-McFarland Elliott Kieff David Hafler Mark J. Daly David Altshuler 《PLoS genetics》2008,4(11)
Lymphoblastoid cell lines (LCLs), originally collected as renewable sources of DNA, are now being used as a model system to study genotype–phenotype relationships in human cells, including searches for QTLs influencing levels of individual mRNAs and responses to drugs and radiation. In the course of attempting to map genes for drug response using 269 LCLs from the International HapMap Project, we evaluated the extent to which biological noise and non-genetic confounders contribute to trait variability in LCLs. While drug responses could be technically well measured on a given day, we observed significant day-to-day variability and substantial correlation to non-genetic confounders, such as baseline growth rates and metabolic state in culture. After correcting for these confounders, we were unable to detect any QTLs with genome-wide significance for drug response. A much higher proportion of variance in mRNA levels may be attributed to non-genetic factors (intra-individual variance—i.e., biological noise, levels of the EBV virus used to transform the cells, ATP levels) than to detectable eQTLs. Finally, in an attempt to improve power, we focused analysis on those genes that had both detectable eQTLs and correlation to drug response; we were unable to detect evidence that eQTL SNPs are convincingly associated with drug response in the model. While LCLs are a promising model for pharmacogenetic experiments, biological noise and in vitro artifacts may reduce power and have the potential to create spurious association due to confounding. 相似文献
166.
Avgerinos E Billa E Papatheofanous M Koullas D Koukios E 《Comptes rendus biologies》2004,327(9-10):927-933
In this paper we present an overview of the main strategies for physicochemical fractionation, sulphur- and chlorine-free delignification, and intelligent characterisation of various types of plant fibres, which have been experimentally investigated, as well as further developed and assessed by this group over the last ten years. 相似文献
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168.
Salvage therapy after two or more prior Helicobacter pylori treatment failures: the super salvage regimen 总被引:5,自引:0,他引:5
Dore MP Marras L Maragkoudakis E Nieddu S Manca A Graham DY Realdi G 《Helicobacter》2003,8(4):307-309
Background. Although effective therapies are available for curing Helicobacter pylori infection, the problem persists about what to do for patients who fail two or more treatment courses despite a good compliance. Aim. To test a twice a day midday quadruple therapy as salvage therapy. Methods. Dyspeptic H. pylori‐infected patients who failed two or more courses of anti‐H. pylori therapy received omeprazole 20 mg, tetracycline 500 mg, metronidazole 500 mg, and bismuth subcitrate caplets 240 mg twice a day (with the midday and evening meals) for 14 days. H. pylori status was evaluated by 13C‐urea breath test and histology 4–6 weeks after therapy. Eradication was defined as no positive test. Results. Seventy‐one patients were enrolled and 68 completed the full 14 days of therapy (mean age 46 years; 28 men). Thirty‐three patients had failed prior treatment twice, 19 had failed three times, and 16 had failed four or more times. The cure rates were: intention to treat = 93% (66/71); (95% CI = 84% to 98%), per protocol = 97% (66/68); (95% CI = 89%– 100%). Success was excellent irrespective of diagnosis, age, prior treatment protocols, or smoking status. Moderate side‐effects were experienced by only two patients. Conclusion. Midday bismuth subcitrate based twice a day quadruple therapy was an excellent salvage therapy. BID midday quadruple regimen should be considered as the therapy of choice. 相似文献
169.
Viennas E Gkantouna V Ioannou M Georgitsi M Rigou M Poulas K Patrinos GP Tzimas G 《Genomics》2012,100(2):93-101
National/ethnic mutation databases aim to document the genetic heterogeneity in various populations and ethnic groups worldwide. We have previously reported the development and upgrade of FINDbase (www.findbase.org), a database recording causative mutations and pharmacogenomic marker allele frequencies in various populations around the globe. Although this database has recently been upgraded, we continuously try to enhance its functionality by providing more advanced visualization tools that would further assist effective data querying and comparisons. We are currently experimenting in various visualization techniques on the existing FINDbase causative mutation data collection aiming to provide a dynamic research tool for the worldwide scientific community. We have developed an interactive web-based application for population-based mutation data retrieval. It supports sophisticated data exploration allowing users to apply advanced filtering criteria upon a set of multiple views of the underlying data collection and enables browsing the relationships between individual datasets in a novel and meaningful way. 相似文献