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181.
- Passiflora edulis f. flavicarpa is the most economically important species in the genus Passiflora. However, the origin of this yellow form of passion fruit remains unclear, being suggested as a hybrid (P. edulis f. edulis × P. ligularis) or wild mutant.
- Here, the origin and genomic relationships of P. edulis f. flavicarpa with some related species in the genus Passiflora (subgenera Decaloba and Passiflora) were investigated using genomic in situ hybridization (GISH). Genomic DNA of 18 species was used as probe, which was hybridized onto chromosomes of P. edulis f. flavicarpa.
- Of all genomic DNA probes tested, none allowed us to identify a specific chromosome set in P. edulis f. flavicarpa. Conversely, probes from the subgenus Passiflora, P. edulis f. edulis, P. alata, P. cincinnata, P. coccinea, P. nitida and P. vitifolia, produced intense and uniform hybridizations on all chromosomes of P. edulis f. flavicarpa. Moreover, probes from P. ligularis, P. foetida and P. sublanceolata produced more intense hybridizations in the terminal region of four chromosomes, corresponding to the DNAr 45S locus, and also dispersed, less intense, hybridization across all chromosomes. Probes from the subgenus Decaloba, P. biflora, P. capsularis, P. cervii, P. coriacea, P. micropetala, P. morifolia, P. rubra and P. suberosa, produced hybridizations restricted to the DNAr 45S sites.
- The hybrid origin of P. edulis f. flavicarpa could not be supported based on the GISH results, and it is suggested that this species is conspecific with P. edulis f. edulis, because the probe with DNA of this form hybridized strongly throughout the target genome. The other putative parent species, P. ligularis, showed only a distant relationship with the target genome. The results also suggest that species of the subgenus Passiflora share many repetitive sequences and that the relationship between subgenera Decaloba and Passiflora is very distant.
182.
Geise Ribeiro Marcel Benadiba Denise de Oliveira Silva Alison Colquhoun 《Cell biochemistry and function》2010,28(1):15-23
The present study reports the synthesis of a novel compound with the formula [Ru2(aGLA)4Cl] according to elemental analyses data, referred to as Ru2GLA. The electronic spectra of Ru2GLA is typical of a mixed valent diruthenium(II,III) carboxylate. Ru2GLA was synthesized with the aim of combining and possibly improving the anti‐tumour properties of the two active components ruthenium and γ‐linolenic acid (GLA). The properties of Ru2GLA were tested in C6 rat glioma cells by analysing cell number, viability, lipid droplet formation, apoptosis, cell cycle distribution, mitochondrial membrane potential and reactive oxygen species. Ru2GLA inhibited cell proliferation in a time and concentration dependent manner. Nile Red staining suggested that Ru2GLA enters the cells and ICP‐AES elemental analysis found an increase in ruthenium from <0.02 to 425 mg/Kg in treated cells. The sub‐G1 apoptotic cell population was increased by Ru2GLA (22 ± 5.2%) when analysed by FACS and this was confirmed by Hoechst staining of nuclei. Mitochondrial membrane potential was decreased in the presence of Ru2GLA (44 ± 2.3%). In contrast, the cells which maintained a high mitochondrial membrane potential had an increase (18 ± 1.5%) in reactive oxygen species generation. Both decreased mitochondrial membrane potential and increased reactive oxygen species generation may be involved in triggering apoptosis in Ru2GLA exposed cells. The EC50 for Ru2GLA decreased with increasing time of exposure from 285 µM at 24 h, 211 µM at 48 h to 81 µM at 72 h. In conclusion, Ru2GLA is a novel drug with antiproliferative properties in C6 glioma cells and is a potential candidate for novel therapies in gliomas. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
183.
Novotnik Breda Nandy Arpita Venkatesan Senthil Velan Radović Jagoš R. Fuente Juan De la Nejadi Siavash Silva Renzo C. Kouris Angela Thangadurai Venkataraman Bryant Steven Karan Kunal Shor Roman Strous Marc Larter Stephen R. 《Reviews in Environmental Science and Biotechnology》2020,19(1):217-240
Reviews in Environmental Science and Bio/Technology - The world’s energy system is still dominated by fossil fuels. While there is a rapid reduction in the cost of renewable energy and the... 相似文献
184.
Beatriz Pereira Moreno Gislaine Cristiane Mantovanelli Letycia Lopes Ricardo Adriano Antnio Silva Rubem Silvrio De Oliveira Emy Luiza Ishii‐Iwamoto Maria Helena Sarragiotto Debora Cristina Baldoqui 《化学与生物多样性》2020,17(3)
Studies of the phytotoxic effects between plants can be a crucial tool in the discovery of innovative compounds with herbicide potential. In this sense, we can highlight ruzigrass (Urochloa ruziziensis), which is traditionally used in the crop rotation system in order to reduce weed emergence. The aim of this work was to characterize the secondary metabolites of ruzigrass and to evaluate its phytotoxic effects. In total, eight compounds were isolated: friedelin, oleanolic acid, α‐amyrin, 1‐dehydrodiosgenone, sitosterol and stigmasterol glycosides, tricin and p‐coumaric acid. Phytotoxic effects of the crude methanolic extract and fractions of ruzigrass were assessed using germination rate, initial seedling growth, and biomass of Bidens pilosa, Euphorbia heterophylla and Ipomoea grandifolia. Chemometric analysis discriminated the weed species into three groups, and B. pilosa was the most affected by fractions of ruzigrass. The phytotoxic activities of 1‐dehydrodiosgenone, tricin, and p‐coumaric acid are also reported, and p‐coumaric acid and 1‐dehydrodiosgenone were active against B. pilosa. 相似文献
185.
da Silva Mateus V. C. Souza Amanda B. de Castro Heizir F. Aguiar Leandro G. de Oliveira Pedro C. de Freitas Larissa 《Bioprocess and biosystems engineering》2020,43(4):615-623
Bioprocess and Biosystems Engineering - This study investigated the synthesis of 2-ethylhexyl oleate catalyzed by Candida antarctica lipase immobilized on magnetic poly(styrene-co-divinylbenzene)... 相似文献
186.
187.
Jean Legeay Claude Husson Benjamin Boudier Eliane Louisanna Christopher Baraloto Heidy Schimann Benoît Marcais Marc Buée 《Environmental microbiology》2020,22(12):5019-5032
The genus Phytophthora represents a group of plant pathogens with broad global distribution. The majority of them cause the collar and root-rot of diverse plant species. Little is known about Phytophthora communities in forest ecosystems, especially in the Neotropical forests where natural enemies could maintain the huge plant diversity via negative density dependence. We characterized the diversity of soil-borne Phytophthora communities in the North French Guiana rainforest and investigated how they are structured by host identity and environmental factors. In this little-explored habitat, 250 soil cores were sampled from 10 plots hosting 10 different plant families across three forest environments (Terra Firme, Seasonally Flooded and White Sand). Phytophthora diversity was studied using a baiting approach and metabarcoding (High-Throughput Sequencing) on environmental DNA extracted from both soil samples and baiting-leaves. These three approaches revealed very similar communities, characterized by an unexpected low diversity of Phytophthora species, with the dominance of two cryptic species close to Phytophthora heveae. As expected, the Phytophthora community composition of the French Guiana rainforest was significantly impacted by the host plant family and environment. However, these plant pathogen communities are very small and are dominated by generalist species, questioning their potential roles as drivers of plant diversity in these Amazonian forests. 相似文献
188.
Henrik Gislason Jeremy Collie Brian R. MacKenzie Anders Nielsen Maria de Fatima Borges Teresa Bottari Corina Chaves Andrey V. Dolgov Jakov Dul
i Daniel Duplisea Heino O. Fock Didier Gascuel Luís Gil de Sola Jan Geert Hiddink Remment ter Hofstede Igor Isajlovi Jnas Pll Jonasson Ole Jrgensen Kristjn Kristinsson Gudrun Marteinsdottir Hicham Masski Sanja Mati‐Skoko Mark R. Payne Melita Peharda Jakup Reinert Jn Slmundsson Cristina Silva Lilja Stefansdottir Francisco Velasco Nedo Vrgo
《Global Ecology and Biogeography》2020,29(5):842-856
189.
Sabela Da Silva‐lvarez Jorge Guerra‐Varela Daniel Sobrido‐Camen Ana Quelle Antn Barreiro‐Iglesias Laura Snchez Manuel Collado 《Aging cell》2020,19(1)
Cellular senescence is a stress response that limits the proliferation of damaged cells by establishing a permanent cell cycle arrest. Different stimuli can trigger senescence but excessive production or impaired clearance of these cells can lead to their accumulation during aging with deleterious effects. Despite this potential negative side of cell senescence, its physiological role as a pro‐regenerative and morphogenetic force has emerged recently after the identification of programmed cell senescence during embryogenesis and during wound healing and limb regeneration. Here, we explored the conservation of tissue injury‐induced senescence in a model of complex regeneration, the zebrafish. Fin amputation in adult fish led to the appearance of senescent cells at the site of damage, and their removal impaired tissue regeneration. Despite many conceptual similarities, this tissue repair response is different from developmental senescence. Our results lend support to the notion that cell senescence is a positive response promoting tissue repair and homeostasis. 相似文献
190.
Thdia Evelyn de Araújo Iliana Claudia Balga Milin Guilherme de Souza Rafaela Jos da Silva Alessandra Monteiro Rosini Pmela Mendona Guirelli Priscila Silva Franco Bellisa Freitas Barbosa Eloisa Amlia Vieira Ferro Idessania Nazareth da Costa 《Cell biology international》2020,44(1):36-50
During pregnancy, the placenta regulates the transfer of oxygen, nutrients, and residual products between the maternal and fetal bloodstreams and is a key determinant of fetal exposure to xenobiotics from the mother. To study the disposition of substances through the placenta, various experimental models are used, especially the perfused placenta, placental villi explants, and cell lineage models. In this context, nanotechnology, an area of study that is on the rise, enables the creation of particles on nanometric scales capable of releasing drugs aimed at specific tissues. An important reason for furthering the studies on transplacental transfer is to explore the potential of nanoparticles (NPs), in new delivery strategies for drugs that are specifically aimed at the mother, the placenta, or the fetus and that involve less toxicity. Due to the fact that the placental barrier is essential for the interaction between the maternal and fetal organisms as well as the possibility of NPs being used in the treatment of various pathologies, the aim of this review is to present the main experimental models used in studying the maternal–fetal interaction and the action of NPs in the placental environment. 相似文献