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61.
Phillip J. Dugger Pedro G. Blendinger Katrin Bhning‐Gaese Lackson Chama Marta Correia D. Matthias Dehling Carine Emer Nina Farwig Evan C. Fricke Mauro Galetti Daniel García Ingo Grass Ruben Heleno Fbio A. F. Jacomassa Suelen Moraes Catherine Moran Marcia C. Muoz Eike Lena Neuschulz Larissa Nowak Augusto Piratelli Marco A. Pizo Marta Quitin Haldre S. Rogers Romn A. Ruggera Francisco Saavedra Mariano S. Snchez Rocío Snchez Vinicio Santilln Dana G. Schabo Fernanda Ribeiro da Silva Srgio Timteo Anna Traveset Maximilian G. R. Vollstdt Matthias Schleuning 《Global Ecology and Biogeography》2019,28(2):248-261
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63.
Sara Martinez Maria del Mar Delgado Ruben Martinez Marin Sergio Alvarez 《Journal of Industrial Ecology》2019,23(4):879-892
The implementation of global sustainability has gained worldwide attention in recent years. The Organization Environmental Footprint, which encompasses 14 impact categories, is a multicriteria measure of the environmental performance of goods and services provided by an organization from a life cycle perspective. In this article, the focus is on quantifying the Organization Environmental Footprint of a construction company in Spain. By applying an environmentally extended input‐output approach, its total footprint and impacts along the supply chain from two consecutive years were calculated. The results show that the environmental impacts from the second year of implementation were significantly higher than those from the first year. The impact category climate change was found to have experienced the greatest increase from one year to the other, with a 31% increase. This work provides an overview of 14 environmental impact categories of the company assessed, as well as recommendations for the implementation of this indicator in companies and public procurement. This approach could pave the way to shape organizations’ action plans and meet the European environmental challenges. 相似文献
64.
Mariana N. So Pedro Ana M. Azevedo Maria R. Aires‐Barros Ruben R. G. Soares 《Biotechnology journal》2019,14(8)
Aqueous two‐phase extraction (ATPE) has been showing significant potential in the biopharmaceutical industry, allowing the selective separation of high‐value proteins directly from unclarified cell culture supernatants. In this context, effective high‐throughput screening tools are critical to perform a rapid empirical optimization of operating conditions. In particular, microfluidic ATPE screening devices, coupled with fluorescence microscopy to continuously monitor the partition of fluorophore‐labeled proteins, have been recently demonstrated to provide short diffusion distances and rapid partition, using minimal reagent volumes. Nevertheless, the currently overlooked influence of the labeling procedure on partition must be carefully evaluated to validate the extrapolation of results to the unlabeled molecule. Here, three fluorophores with different global charge and reactivity selected to label immunoglobulin G (IgG) at degrees of labeling (DoL) ranging from 0.5 to 7.6. Labeling with BODIPY FL maleimide (DoL = 0.5), combined with tris(2‐carboxyethyl) phosphine (TCEP) to generate free thiol groups, is the most promising strategy to minimize the influence of the fluorophore on partition. In particular, the partition coefficient (Kp) measured in polyethylene glycol (PEG) 3350–phosphate systems with and without the addition of NaCl using microtubes (batch) or microfluidic devices (continuous) is comparable to those quantified for the native protein. 相似文献
65.
Benedetta Artegiani Lisa van Voorthuijsen Rik G.H. Lindeboom Daniëlle Seinstra Inha Heo Pablo Tapia Carmen López-Iglesias Daniel Postrach Talya Dayton Rurika Oka Huili Hu Ruben van Boxtel Johan H. van Es Johan Offerhaus Peter J. Peters Jacco van Rheenen Michiel Vermeulen Hans Clevers 《Cell Stem Cell》2019,24(6):927-943.e6
66.
Neurotrophins, such as brain derived neurotrophic factor (BDNF), do not cross the blood-brain barrier (BBB). Certain monoclonal antibodies (MAb) to the human insulin receptor (HIR) do cross the BBB via receptor-mediated transport, and can act as a molecular Trojan horse to ferry across the BBB an attached drug. A genetically engineered fusion protein was produced whereby the amino terminus of human BDNF is fused to the carboxyl terminus of the heavy chain of a chimeric HIRMAb. The HIRMAb-BDNF fusion protein reacted equally with antibodies to human IgG and BDNF. The bi-functionality of the fusion protein was retained as the affinity of the fusion protein for the HIR was identical to that of the chimeric HIRMAb, and the affinity of the fusion protein for the trkB receptor was identical to that of BDNF. The fusion protein was equi-potent with BDNF in a neuroprotection assay in human neural cells. The pharmacokinetics (PK) of the fusion protein was examined in the adult Rhesus monkey. The mean residence time (MRT) of the fusion protein in blood was >100-fold longer than the MRT of BDNF. Therapeutic levels of BDNF were produced in primate brain following the intravenous administration of the fusion protein. A fusion protein tandem vector was engineered that allowed for isolation of a CHO cell line that produced the fusion protein at high levels in serum free medium. Neurotrophins, such as BDNF, can be re-formulated to enable these molecules to cross the human BBB, and such fusion proteins represent a new class of human neurotherapeutics. 相似文献
67.
The FDA has published guidelines by which to carry out and interpret in vitro induction studies using hepatocytes but do researchers in pharmaceutical companies actually follow these to the letter? In a survey of 30 participants in the pharmaceutical industry, 19 questions were posed regarding the species investigated, methodologies and interpretations of the data. Also addressed was the in-house decision making processes as a result of in vitro induction data. The survey showed that, although the basic methods were similar, no two researchers carried out and interpreted induction assays in exactly the same way. No single method was superior but all included enzyme activities as the major end point. Hepatocytes from animal species were used to confirm animal in vivo data but only human hepatocytes were used to predict human induction responses. If a compound was found to be positive in an in vitro induction assay, few would halt the development of the compound. The majority would consider other properties of the compound (bioavailability, clearance and therapeutic concentrations) and follow the FDA recommendation to conduct clinical drug-drug interaction studies. Overall, the results from this survey indicate that there is no standard pharmaceutical industry method or evaluation criterion by which in vitro assays are carried out. Rather than adhering to the FDA guidelines, some adapt methods and interpretation according to their own experience and need (whether screening or lead optimisation). There was general consensus that studies using human hepatocyte cultures currently provide the best indication of the in vivo induction potential of NCEs. In addition, the assessment of in vitro induction data from the literature suggest that the two-fold induction threshold and the percent of positive control criteria may not be the best methods to accurately assess the in vivo induction potential of a drug. Although the two-fold induction criterion is now obsolete, more predictive models for determining the clinical induction potential are needed. Alternative models are proposed and discussed herein. 相似文献
68.
Banner SH Ruben LN Johnson RO 《Journal of experimental zoology. Part A, Ecological genetics and physiology》2007,307(2):84-90
Microgel cell electrophoresis has been used with various species to measure breakage of DNA and DNA repair following exposure to the radiomimetic antibiotic, bleomycin. With humans, a high degree of DNA damage is considered to be predictive of cancer susceptibility. Non-isogeneic Xenopus laevis, the South African clawed toad, rarely develop spontaneous or induced cancers. Here, we investigate bleomycin-induced DNA damage and repair in splenic lymphocytes of this species to test consistency with cancer predictability. As X. laevis is pseudotetraploid in nature, while Xenopus tropicalis is diploid, we additionally explore the effect of polyploidy on DNA damage and repair in these vertebrates. The results show that higher doses of bleomycin are required to induce comparable levels of DNA damage in both Xenopus species, than in humans. X. tropicalis, the diploid, is more bleomycin-sensitive than is X. laevis. Additionally, repair rates of damaged DNA of X. laevis lymphocytes are more rapid than those of X. tropicalis, although both are hours slower than human leukocytes. While no data exist on cancer susceptibility in X. tropicalis, the results suggest greater susceptibility to cancer than X. laevis, but less than in humans. Thus, polyploidy serves as a protection against DNA damage and allows more rapid repair. 相似文献
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70.
Rhizobia in the plant microbiota The plant microbiota is of critical importance for plant growth and survival in soil. To explore mechanisms underlying plant‐microbiota interactions, defined commensal communities can be composed from microbiota culture collections and co‐cultivated with germ‐free plants to determine their impact on plant growth and health. The order Rhizobiales belongs to the core microbiota and includes nitrogen‐fixing bacteria that are known to engage in symbiotic interactions with legumes. Compatible host‐symbiont pairs are needed for a functional symbiosis, which involves the activation of highly specialized and interdependent signaling pathways between the two partners. Comparative genome analysis of more than 1,300 legume symbionts and rhizobial root commensals from non‐leguminous plants revealed that the most recent common ancestor of rhizobia lacked the gene repertoire needed for symbiosis and was able to colonize roots of a wide variety of plants. During evolution, key symbiosis genes were acquired multiple independent times by commensals belonging to different families of the Rhizobiales order. 相似文献