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101.
In order to study hybridisation, taxonomic boundaries and phylogeography in the genus Pseudopanax (Araliaceae), we developed seven novel microsatellite loci from enriched genomic libraries of P. lessonii and P. crassifolius. These loci were characterised in 16 individuals from a single population of P. crassifolius, and displayed 2–11 alleles per locus. Observed heterozygosities ranged from 0.063 to 0.688. Most loci were polymorphic in
the closely related Pseudopanax species, and several loci amplified widely across the Araliaceae. 相似文献
102.
François Courchesne Marie-Claude Turmel Benoît Cloutier-Hurteau Simon Constantineau Lara Munro Michel Labrecque 《International journal of phytoremediation》2017,19(6):545-554
The phytoextraction of the trace elements (TEs) As, Cd, Cu, Ni, Pb, and Zn by willow cultivars (Fish Creek, SV1 and SX67) was measured during a 3-year field trial in a mildly contaminated soil. Biomass ranged from 2.8 to 4.4 Mg/ha/year at 30,000 plants/ha. Shoots (62%) were the main component followed by leaves (23%) and roots (15%). Biomass was positively linked to soluble soil dissolved organic carbon, K, and Mg, while TEs, not Cd and Zn, had a negative effect. The TE concentration ranking was: Zn > Cu > Cd > Ni, Pb > As, and distribution patterns were: (i) minima in shoots (As, Ni), (ii) maxima in leaves (Cd, Zn), or (iii) maxima in roots (Cu, Pb). Correlations between soil and plant TE were significant for the six TEs in roots. The amounts extracted were at a maximum for Zn, whereas Fish Creek and SV1 extracted more TE than SX67. More than 60% (91–94% for Cd and Zn) of the total TE was in the aboveground parts. Uptake increased with time because of higher biomass. Fertilization, the selection of cultivars, and the use of complementary plants are required to improve productivity and Cd and Zn uptake. 相似文献
103.
Lara Massai Luigi Messori Nicola Micale Tanja Schirmeister Louis Maes Dolores Fregona Maria Agostina Cinellu Chiara Gabbiani 《Biometals》2017,30(2):313-320
Gold compounds form a new class of promising metal-based drugs with a number of potential therapeutic applications, particularly in the fields of anticancer and antimicrobial treatments. Previous research revealed that a group of structurally diverse gold compounds cause conspicuous inhibition of the protease activities of the human proteasome. Given the pharmacological importance of protease inhibition, the present study further explored whether these gold compounds might inhibit a few other proteases that are accepted druggable targets for disease treatment. In particular, four distinct cysteine proteases were considered here: cathepsin B and L that play a primary role in tumor-cell invasion and metastasis; rhodesain, the major cathepsin L-like cysteine protease of Trypanosoma brucei rhodesiense and CPB2.8ΔCTE, a Leishmania mexicana mature cysteine protease. Based on the encouraging results obtained for some of the tested gold compounds on the two parasitic cysteine proteases, especially against CPB2.8ΔCTE, with IC50s in the micromolar range, we next evaluated whether those gold compounds might contrast effectively the growth of the respective protozoa and indeed important antiprotozoal properties were disclosed; on the other hand a certain lack of selectivity was highlighted. Also, no direct or clear correlation could be established between the in vitro antiprotozoal properties and the level of protease inhibition. The implications of these results are discussed in relation to possible pharmaceutical applications. 相似文献
104.
Glycomics, i.e. the high-throughput analysis of carbohydrates, has yet to reach the level of ease and import of its counterparts, genomics and proteomics, due to the difficulties inherent in carbohydrate analysis. The advent of lectin microarray technology addresses many of these problems, providing a straightforward approach for glycomic analysis. However, current microarrays are limited to the available lectin set, which consists mainly of plant lectins isolated from natural sources. These lectins have inherent problems including inconsistent activity and availability. Also, many plant lectins are glycosylated, complicating glycomic evaluation of complex samples, which may contain carbohydrate-binding proteins. The creation of a recombinant, well-defined lectin set would resolve many of these issues. Herein, we describe an efficient strategy for the systematic creation of recombinant lectins for use in microarray technology. We present a small panel of simple-to-purify bacterially-derived lectins that show reliable activity and define their binding specificities by both carbohydrate microarray and ELISA. We utilize this panel to create a recombinant lectin microarray that is able to distinguish glycopatterns for both proteins and cell samples. This work opens the door to the establishment of a vast set of defined lectins via high-throughout approaches, advancing lectin microarray technology for glycomic analysis. 相似文献
105.
Anubha Sagar Carolin Klemm Lara Hartjes Stefanie Mauerer Ger van Zandbergen Barbara Spellerberg 《PloS one》2013,8(4)
S. agalactiae (group B streptococci, GBS) is a major microbial pathogen in human neonates and causes invasive infections in pregnant women and immunocompromised individuals. The S. agalactiae β-hemolysin is regarded as an important virulence factor for the development of invasive disease. To examine the role of β-hemolysin in the interaction with professional phagocytes, the THP-1 monocytic cell line and human granulocytes were infected with a serotype Ia S. agalactiae wild type strain and its isogenic nonhemolytic mutant. We could show that the nonhemolytic mutants were able to survive in significantly higher numbers than the hemolytic wild type strain, in THP-1 macrophage-like cells and in assays with human granulocytes. Intracellular bacterial multiplication, however, could not be observed. The hemolytic wild type strain stimulated a significantly higher release of Tumor Necrosis Factor-α than the nonhemolytic mutant in THP-1 cells, while similar levels of the chemokine Interleukin-8 were induced. In order to investigate bacterial mediators of IL-8 release in this setting, purified cell wall preparations from both strains were tested and found to exert a potent proinflammatory stimulus on THP-1 cells. In conclusion, our results indicate that the β-hemolysin has a strong influence on the intracellular survival of S. agalactiae and that a tightly controlled regulation of β-hemolysin expression is required for the successful establishment of S. agalactiae in different host niches. 相似文献
106.
Anna S. Weiss Anna G. Burrichter Abilash Chakravarthy Durai Raj Alexandra von Strempel Chen Meng Karin Kleigrewe Philipp C. Münch Luis Rssler Claudia Huber Wolfgang Eisenreich Lara M. Jochum Stephanie Ging Kirsten Jung Chiara Lincetto Johannes Hübner Georgios Marinos Johannes Zimmermann Christoph Kaleta Alvaro Sanchez Brbel Stecher 《The ISME journal》2022,16(4):1095
A key challenge in microbiome research is to predict the functionality of microbial communities based on community membership and (meta)-genomic data. As central microbiota functions are determined by bacterial community networks, it is important to gain insight into the principles that govern bacteria-bacteria interactions. Here, we focused on the growth and metabolic interactions of the Oligo-Mouse-Microbiota (OMM12) synthetic bacterial community, which is increasingly used as a model system in gut microbiome research. Using a bottom-up approach, we uncovered the directionality of strain-strain interactions in mono- and pairwise co-culture experiments as well as in community batch culture. Metabolic network reconstruction in combination with metabolomics analysis of bacterial culture supernatants provided insights into the metabolic potential and activity of the individual community members. Thereby, we could show that the OMM12 interaction network is shaped by both exploitative and interference competition in vitro in nutrient-rich culture media and demonstrate how community structure can be shifted by changing the nutritional environment. In particular, Enterococcus faecalis KB1 was identified as an important driver of community composition by affecting the abundance of several other consortium members in vitro. As a result, this study gives fundamental insight into key drivers and mechanistic basis of the OMM12 interaction network in vitro, which serves as a knowledge base for future mechanistic in vivo studies.Subject terms: Microbiome, Microbial ecology 相似文献
107.
Background
Implicit racial bias denotes socio-cognitive attitudes towards other-race groups that are exempt from conscious awareness. In parallel, other-race faces are more difficult to differentiate relative to own-race faces – the “Other-Race Effect.” To examine the relationship between these two biases, we trained Caucasian subjects to better individuate other-race faces and measured implicit racial bias for those faces both before and after training.Methodology/Principal Findings
Two groups of Caucasian subjects were exposed equally to the same African American faces in a training protocol run over 5 sessions. In the individuation condition, subjects learned to discriminate between African American faces. In the categorization condition, subjects learned to categorize faces as African American or not. For both conditions, both pre- and post-training we measured the Other-Race Effect using old-new recognition and implicit racial biases using a novel implicit social measure – the “Affective Lexical Priming Score” (ALPS). Subjects in the individuation condition, but not in the categorization condition, showed improved discrimination of African American faces with training. Concomitantly, subjects in the individuation condition, but not the categorization condition, showed a reduction in their ALPS. Critically, for the individuation condition only, the degree to which an individual subject''s ALPS decreased was significantly correlated with the degree of improvement that subject showed in their ability to differentiate African American faces.Conclusions/Significance
Our results establish a causal link between the Other-Race Effect and implicit racial bias. We demonstrate that training that ameliorates the perceptual Other-Race Effect also reduces socio-cognitive implicit racial bias. These findings suggest that implicit racial biases are multifaceted, and include malleable perceptual skills that can be modified with relatively little training. 相似文献108.
Alfredo Attisano Lara B. Groß Nozomu J. Sato Yuji Okahisa Keita D. Tanaka Roman Gula Keisuke Ueda Jörn Theuerkauf 《Journal of avian biology》2020,51(7)
Predation and brood parasitism are common reasons for nesting failure in passerine species and the additive impact by invasive species is a major conservation concern, particularly on tropical islands. Recognising the relative contribution of the different components of nesting failure rates is important to understand co-evolutionary interactions within brood parasite–host systems. In the remote archipelago of New Caledonia, the fan-tailed gerygone Gerygone flavolateralis is the exclusive host of the brood-parasitic shining bronze-cuckoo Chalcites lucidus. Additionally, invasive rodents also possibly have an impact on breeding success. To estimate the impact of potential nest predators, we 1) video monitored nests to identify predators, 2) estimated the probability of predation based on nest visibility and predator abundance and 3) tested the possibility that the location of experimental nests and lack of odour cues decrease the predation by rodents. In addition, we estimated nest survival rates using data collected in different habitats over the course of eight breeding seasons. Nesting success of fan-tailed gerygones was relatively low and predation was the main cause of nesting failure. We recorded mainly predation by native birds, including the shining bronze-cuckoo, whereas predation by rats was rare. In open habitats predation by cuckoos was much lower than predation by other avian predators. Neither predator activity around nests nor nest visibility influenced the probability of predation. Experimental nests in more accessible locations and containing an odorous bait were more exposed to rodent predation. Apparently, the fan-tailed gerygone has either never been specifically vulnerable to predation by rats or has developed anti-predator adaptations. 相似文献
109.
Irem Dogan Turacli Haldun Umudum Arzu Pampal Tuba Candar Lara Kavasoglu Yaren Sari 《Molecular biology reports》2018,45(3):195-201
There is a growing body of evidence about metformin being effective in cancer therapy. Despite controversies about the ways of its effectiveness, several ongoing clinical trials are evaluating the drug when used as an adjuvant or a neo-adjuvant agent. We aimed to investigate metformin’s effects on proliferation, metastasis, and hormone receptor expressions in breast cancer cell line MCF-7 incubated in two different glucose conditions. MCF-7 cells were incubated in high or low glucose media and treated with various doses of metformin. The cell viability was studied using MTT test. The Ki-67, estrogen and progesterone receptor expression were evaluated by ICC and galectin-3 expression was evaluated by ELISA or spectrophotometrically. The cell viability following consecutive metformin doses in either glucose condition for 24 and 48 h represented a significant decrease when compared to control. The proliferation detected in low glucose medium following metformin at doses < 20 mM was found significantly decreased when compared to high glucose medium at 48 h. In terms of galectin-3 levels, the increase in high glucose medium treated with metformin and the decrease in low glucose medium were found statistically significant when compared to control. Progesterone receptor staining demonstrated a significant increase in low glucose medium. Our findings represent better outcomes for cancer lines incubated in low glucose medium treated with metformin in terms of viability, receptor expression and metastatic activity, and highlight the potential benefit of metformin especially in restraining the cancer cell’s ability to cope energetic stress in low glucose conditions. 相似文献
110.
Luis Alberto Henríquez-Hernández Almudena Valenciano Palmira Foro-Arnalot María Jesús álvarez-Cubero José Manuel Cozar José Francisco Suárez-Novo Manel Castells-Esteve Adriana Ayala-Gil Pablo Fernández-Gonzalo Montse Ferrer Ferrán Guedea Gemma Sancho-Pardo Jordi Craven-Bartle María José Ortiz-Gordillo Patricia Cabrera-Roldán Estefanía Herrera-Ramos Pedro C. Lara 《PloS one》2013,8(7)