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61.
The novelty of synthetic biology lies in the use of synthesized parts that can be arranged to make useful products. Such advanced, high-throughput genetic engineering projects redesign and fabricate existing biological systems as well as new biological parts, devices and systems that do not occur in nature. This Opinion discusses challenges raised by synthetic biology for public acceptance, regulation, commercialization and the emerging global issue of access to genetic resources and information. As with all new fields of research, maintaining the trust of the public and policy regulators is paramount. Hype and exaggerated claims are counterproductive to developing adaptive and ethically sound regulatory models responsive to stakeholder concerns. 相似文献
62.
Grünblatt E Geissler J Jacob CP Renner T Müller M Bartl J Gross-Lesch S Riederer P Lesch KP Walitza S Gerlach M Schmitt A 《Attention deficit and hyperactivity disorders》2012,4(2):77-84
Attention-deficit hyperactivity disorder (ADHD) is a common behavioural disorder that affects not only children and adolescents but also adults; however, diagnosis of adult ADHD is difficult because patients seem to have reduced externalized behaviour. ADHD is a multifactorial disorder in which many genes, all with small effects, are thought to cause the disorder in the presence of unfavourable environmental conditions. Therefore, in this pilot study, we explored the expression profile of a list of previously established candidate genes in peripheral blood samples from adult ADHD subjects (n = 108) and compared these results with those of healthy controls (n = 35). We demonstrate that combining the gene expression levels of dopamine transporter (SLC6A3), dopamine D5 receptor, tryptophan hydroxylase-1, and SNAP25 as predictors in a regression model resulted in sensitivity and specificity of over 80 % (ROC: max R(2) = 0.587, AUC = 0.917, P < 0.001, 95 % CI: 0.900-0.985). In conclusion, the combination of these four genes could represent a potential method for estimating risk and could be of diagnostic value for ADHD. Nevertheless, further investigation in a larger independent population including different subtypes of ADHD (inattentive, hyperactive, or combined type) patients is required to obtain more specific sets of biomarkers for each subtype as well as to differentiate between child, adolescent, and adulthood forms. 相似文献
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Actin exists as a monomer (G-actin) which can be polymerized to filaments) F-actin) that under the influence of actin-binding proteins and polycations bundle and contribute to the formation of the cytoskeleton. Bundled actin from lysed cells increases the viscosity of sputum in lungs of cystic fibrosis patients. The human host defense peptide LL-37 was previously shown to induce actin bundling and was thus hypothesized to contribute to the pathogenicity of this disease. In this work, interactions between actin and the cationic LL-37 were studied by optical, proteolytic and surface plasmon resonance methods and compared to those obtained with scrambled LL-37 and with the cationic protein lysozyme. We show that LL-37 binds strongly to CaATP-G-actin while scrambled LL-37 does not. While LL-37, at superstoichiometric LL-37/actin concentrations polymerizes MgATP-G-actin, at lower non-polymerizing concentrations LL-37 inhibits actin polymerization by MgCl2 or NaCl. LL-37 bundles Mg-F-actin filaments both at low and physiological ionic strength when in equimolar or higher concentrations than those of actin. The LL-37 induced bundles are significantly less sensitive to increase in ionic strength than those induced by scrambled LL-37 and lysozyme. LL-37 in concentrations lower than those needed for actin polymerization or bundling, accelerates cleavage of both monomer and polymer actin by subtilisin. Our results indicate that the LL-37-actin interaction is partially electrostatic and partially hydrophobic and that a specific actin binding sequence in the peptide is responsible for the hydrophobic interaction. LL-37-induced bundles, which may contribute to the accumulation of sputum in cystic fibrosis, are dissociated very efficiently by DNase-1 and also by cofilin. 相似文献
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Costa NJ Bombardieri CR Kuribayashi JS de Camargo MM Andrade LH Kagohara E Espósito BP 《化学与生物多样性》2008,5(10):2156-2159
It is shown that metal complexes of the biodegradable ligand ethylenediaminedisuccinic acid (edds) present antimicrobial activity towards fungi and bacteria. [Cd(edds)], in particular, is more toxic than free Cd2+ to Aspergillus niger, behaving as a 'Trojan Horse' in the facilitated delivery of the toxic metal into the fungus. 相似文献
67.
Adriane S Nakashima Carla M Prado Tatiana Lan?as Viviane C Ruiz David I Kasahara Edna A Leick-Maldonado Marisa Dolhnikoff Milton A Martins Iolanda F L C Tibério 《Journal of applied physiology》2008,104(6):1778-1785
Recent studies emphasize the presence of alveolar tissue inflammation in asthma. Immunotherapy has been considered a possible therapeutic strategy for asthma, and its effect on lung tissue had not been previously investigated. Measurements of lung tissue resistance and elastance were obtained before and after both ovalbumin and acetylcholine challenges. Using morphometry, we assessed eosinophil and smooth muscle cell density, as well as collagen and elastic fiber content, in lung tissue from guinea pigs with chronic pulmonary allergic inflammation. Animals received seven inhalations of ovalbumin (1-5 mg/ml; OVA group) or saline (SAL group) during 4 wk. Oral tolerance (OT) was induced by offering ad libitum ovalbumin 2% in sterile drinking water starting with the 1st inhalation (OT1 group) or after the 4th (OT2 group). The ovalbumin-exposed animals presented an increase in baseline and in postchallenge resistance and elastance related to baseline, eosinophil density, and collagen and elastic fiber content in lung tissue compared with controls. Baseline and post-ovalbumin and acetylcholine elastance and resistance, eosinophil density, and collagen and elastic fiber content were attenuated in OT1 and OT2 groups compared with the OVA group. Our results show that inducing oral tolerance attenuates lung tissue mechanics, as well as eosinophilic inflammation and extracellular matrix remodeling induced by chronic inflammation. 相似文献
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Gakamsky A Schechtman E Caplan SR Eisenbach M 《The International journal of developmental biology》2008,52(5-6):481-487
The detection of chemotaxis-related changes in the swimming behavior of mammalian spermatozoa in a spatial chemoattractant gradient has hitherto been an intractable problem. The difficulty is that the fraction of responsive cells in the sperm population is very small and that the large majority of the cells, though non-responsive, are motile too. Assessment of the chemotactic effects in a spatial gradient is also very sensitive to the quality of sperm tracking. To overcome these difficulties we propose a new approach, based on the analysis of the distribution of instantaneous directionality angles made by spermatozoa in a spatial gradient versus a no-gradient control. Although the use of this parameter does not allow identification of individual responding cells, it is a reliable measure of directionality, independent of errors in cell tracking caused by cell collisions, track crossings, and track splitting. The analysis identifies bias in the swimming direction of a population relative to the gradient direction. It involves statistical chi(2) tests of the very large sample of measured angles, where the critical chi(2) values are adjusted to the sample size by the bootstrapping procedure. The combination of the newly measured parameter and the special analysis provides a highly sensitive method for the detection of a chemotactic response, even a very small one. 相似文献
70.