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de Farias Bianca Xavier Costa Ana Beatriz Engel Nicole Alessandra de Souza Goldim Mariana Pereira da Rosa Turatti Cristini Cargnin-Cavalho Anderson Fortunato Jucélia Jeremias Petronilho Fabricia Jeremias Isabela Casagrande Rezin Gislaine Tezza 《Neurochemical research》2020,45(10):2487-2498
Neurochemical Research - Obesity is characterized by chronic inflammation of low grade. The cholinergic anti-inflammatory pathway favors the reduction of the inflammatory response. In this work the... 相似文献
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Approaches to homozygosity mapping and exome sequencing for the identification of novel types of CDG
Gert Matthijs Daisy Rymen María Beatriz Bistué Millón Erika Souche Valérie Race 《Glycoconjugate journal》2013,30(1):67-76
In the past decade, the identification of most genes involved in Congenital Disorders of Glycosylation (CDG) (type I) was achieved by a combination of biochemical, cell biological and glycobiological investigations. This has been truly successful for CDG-I, because the candidate genes could be selected on the basis of the homology of the synthetic pathway of the dolichol linked oligosaccharide in human and yeast. On the contrary, only a few CDG-II defects were elucidated, be it that some of the discoveries represent wonderful breakthroughs, like e.g, the identification of the COG defects. In general, many rare genetic defects have been identified by positional cloning. However, only a few types of CDG have effectively been elucidated by linkage analysis and so-called reverse genetics. The reason is that the families were relatively small and could—except for CDG-PMM2—not be pooled for analysis. Hence, a large number of CDG cases has long remained unsolved because the search for the culprit gene was very laborious, due to the heterogeneous phenotype and the myriad of candidate defects. This has changed when homozygosity mapping came of age, because it could be applied to small (consanguineous) families. Many novel CDG genes have been discovered in this way. But the best has yet to come: what we are currently witnessing, is an explosion of novel CDG defects, thanks to exome sequencing: seven novel types were published over a period of only two years. It is expected that exome sequencing will soon become a diagnostic tool, that will continuously uncover new facets of this fascinating group of diseases. 相似文献
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Tatiana Visnevschi-Necrasov Miguel A. Faria Sara C. Cunha J. Harris Harald W. E. Meimberg Manuel A. C. Curto M. Graça Pereira M. Beatriz P. P. Oliveira Eugénia Nunes 《Plant Systematics and Evolution》2013,299(2):357-367
This study presents the results of the identification and quantification of 12 isoflavones (prunetin, irilone, pseudobaptigenin, glycitein, daidzin, genistin, daidzein, pratensein, puerarin, biochanin A, formononetin and genistein) in 23 species of Trifolium (T. arvense, T. pratense, T. ligusticum, T. striatum, T. lappaceum, T. angustifolium, T. hirtum, T. subterraneum, T. isthmocarpum, T. stellatum, T. mutabile, T. strictum, T. fragiferum, T. alexandrinum, T. tomentosum. T. nigrescens subsp. petrisavii, T. nigrescens, T. glomeratum, T. subterraneum subsp. brachycalycinum, T. cherleri, T. resupinatum, T. campestre and T. repens). Isoflavones were extracted by an MSPD method and analyzed with HPLC coupled with a diode-array detector. The evaluation of molecular phylogeny of the IFS gene and the relation with isoflavone content was also performed. Five species (T. subterraneum subsp. brachycalycinum, T. alexandrinum, T. pratense, T. subterraneum and T. lappaceum) were identified with high levels of biochanin A (431–83 mg/kg), formononetin (72–365 mg/kg) and genistein (9–509 mg/kg), which could be utilized as alternative sources for the nutraceutical industry. Genetic phylogeny for the IFS gene was found in the species studied, with 20 out of 23 species having been divided into two clades, while the remaining three were genetically distant. Based on our results, we confirm the direct correlation between IFS gene polymorphism and isoflavones content in species of Trifolium particularly noted for formononetin. Therefore, the IFS gene can be utilized for screening Trifolium genotypes for formononetin. The relation of the three isoflavones' contents and the molecular phylogeny of plants determined by the IFS sequences, as a screening marker for plants with high isoflavone contents in Trifolium species, are to the best of our knowledge described for the first time. 相似文献
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Pablo Martin Lopez Luciana Beatriz Abrahan Martin Roland Ralph Verónica Sandra Valentinuzzi 《Chronobiology international》2013,30(10):1402-1412
ABSTRACTInsects express diverse behavioral rhythms synchronized to environmental cycles. While circadian entrainment to light–dark cycles is ubiquitous in living organisms, synchronization to non-photic cycles may be critical for hematophagous bugs that depend on rhythmic hosts. The purpose was to determine whether Triatoma infestans are capable of synchronizing to the circadian rhythms of potential hosts with temporally distinct activity patterns; and, if so, if this synchronization occurs through masking or entrainment. Precise synchronization with the food source may be critical for the insects’ survival due to the specific predatory or defensive nature of each host. Kissing bugs were housed in a compartment in constant dark, air-flow-connected to another compartment with a nocturnal or a diurnal host; both hosts were synchronized to a light–dark cycle. The activity rhythms of kissing bugs were modulated by the daily activity rhythms of the vertebrates. Effects were a decrease in the endogenous circadian period, independent of the host being nocturnal or diurnal; in some cases relative coordination occurred and in others synchronization was clearly achieved. Moreover, splitting and bimodality arose, phenomena that were also affected by the host presence. The results indicate that T. infestans were able to detect the non-photic cycle of their potential hosts, an ability that surely facilitates feeding and hinders predation risk. Understanding triatomines behavior is of fundamental importance to the design of population control methods. 相似文献
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Anik Désormeaux Mathieu Coutu Halima Medjahed Beatriz Pacheco Alon Herschhorn Christopher Gu Shi-Hua Xiang Youdong Mao Joseph Sodroski Andrés Finzi 《Journal of virology》2013,87(5):2549-2562
The trimeric envelope glycoprotein (Env) of human immunodeficiency virus type 1 (HIV-1) mediates virus entry into host cells. CD4 engagement with the gp120 exterior envelope glycoprotein subunit represents the first step during HIV-1 entry. CD4-induced conformational changes in the gp120 inner domain involve three potentially flexible topological layers (layers 1, 2, and 3). Structural rearrangements between layer 1 and layer 2 have been shown to facilitate the transition of the envelope glycoprotein trimer from the unliganded to the CD4-bound state and to stabilize gp120-CD4 interaction. However, our understanding of CD4-induced conformational changes in the gp120 inner domain remains incomplete. Here, we report that a highly conserved element of the gp120 inner domain, layer 3, plays a pivot-like role in these allosteric changes. In the unliganded state, layer 3 modulates the association of gp120 with the Env trimer, probably by influencing the relationship of the gp120 inner and outer domains. Importantly, layer 3 governs the efficiency of the initial gp120 interaction with CD4, a function that can also be fulfilled by filling the Phe43 cavity. This work defines the functional importance of layer 3 and completes a picture detailing the role of the gp120 inner domain in CD4-induced conformational transitions in the HIV-1 Env trimer. 相似文献
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Claudia A. M. Russo Beatriz Mello Annelise Frazão Carolina M. Voloch 《Zoological Journal of the Linnean Society》2013,169(4):765-775
Drosophila is the genus responsible for the birth of experimental genetics, but the taxonomy of drosophilids is difficult because of the overwhelming diversity of the group. In this study, we assembled sequences for 358 species (14 genera, eight subgenera, 57 species groups, and 65 subgroups) to generate a maximum‐likelihood topology and a Bayesian timescale. In addition to sampling an unprecedented diversity of Drosophila lineages, our analyses incorporated a geographical perspective because of the high levels of endemism. In our topology, Drosophila funebris (Fabricius, 1787) (the type species of Drosophila) is tightly clustered with the pinicola subgroup in a North American clade within subgenus Drosophila. The type species of other drosophilid genera fall within the Drosophila radiation, presenting interesting prospects for the phylogenetic taxonomy of the group. Our timescale suggests that a few drosophilid lineages survived the Cretaceous–Palaeogene (K‐Pg) extinction. The drosophilid diversification began during the Palaeocene in Eurasia, but peaked during the Miocene, an epoch of drastic climatic changes. The most recent common ancestor of the clades corresponding to subgenera Sophophora and Drosophila lived approximately 56 Mya. Additionally, Hawaiian drosophilids diverged from an East Asian lineage approximately 26 Mya, which is similar to the age of the oldest emerging atoll in the Hawaiian–Emperor Chain. Interestingly, the time estimates for major geographical splits (New World versus Asia and Africa versus Asia) were highly similar for independent lineages. These results suggest that vicariance played a significant role in the radiation of fruit flies. © 2013 The Linnean Society of London 相似文献