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41.
Heidi L. Hargarten Mattias L. Johansson Daniel C. Reed Nelson C. Coelho David A. Siegel Filipe Alberto 《Journal of phycology》2020,56(1):110-120
We conducted a population genetic analysis of the stalked kelp, Pterygophora californica, in the Santa Barbara Channel, California, USA. The results were compared with previous work on the genetic differentiation of giant kelp, Macrocystis pyrifera, in the same region. These two sympatric kelps not only share many life history and dispersal characteristics but also differ in that dislodged P. californica does not produce floating rafts with buoyant fertile sporophytes, commonly observed for M. pyrifera. We used a comparative population genetic approach with these two species to test the hypothesis that the ability to produce floating rafts increases the genetic connectivity among kelp patches in the Santa Barbara Channel. We quantified the association of habitat continuity and oceanographic distance with the genetic differentiation observed in stalked kelp, like previously conducted for giant kelp. We compared both overall (across all patches) and pairwise (between patches) genetic differentiation. We found that oceanographic transit time, habitat continuity, and geographic distance were all associated with genetic connectivity in P. californica, supporting similar previous findings for M. pyrifera. Controlling for differences in heterozygosity between kelp species using Jost's DEST, we showed that global differentiation and pairwise differentiation were similar among patches between the two kelp species, indicating that they have similar dispersal capabilities despite their differences in rafting ability. These results suggest that rafting sporophytes do not play a significant role in effective dispersal of M. pyrifera at ecologically relevant spatial and temporal scales. 相似文献
42.
Magnusson Catarina Jugdaohsingh Ravin Hulthen Lena Westerlund Anna Powell Jonathan J. Ransjö Maria 《Biological trace element research》2020,194(2):321-327
Biological Trace Element Research - Silicon is a trace element found mainly in plant-based food and proposed to be beneficial for bone health. Urinary excretion of Si has been shown to be a... 相似文献
43.
Anton Débora Bublitz Guzman Frank Lino Vetö Nicole Moreira Krause Felipe Augusto Kulcheski Franceli Rodrigues Coelho Ana Paula Durand Duarte Guilherme Leitão Margis Rogério Dillenburg Lúcia Rebello Turchetto-Zolet Andreia Carina 《Molecular biology reports》2020,47(2):1033-1043
Molecular Biology Reports - Eugenia uniflora is an Atlantic Forest native species, occurring in contrasting edaphoclimatic environments. The identification of genes involved in response to abiotic... 相似文献
44.
Tarsila Barros Moraes Carlos Eduardo Diaz Jacques Andrea Pereira Rosa Giovana Reche Dalazen Melaine Terra Juliana Gonzalez Coelho Carlos Severo Dutra-Filho 《Cellular and molecular neurobiology》2013,33(2):253-260
Phenylketonuria (PKU) is an inherited metabolic disorder caused by deficiency of phenylalanine hydroxylase which leads to accumulation of phenylalanine and its metabolites in tissues of patients with severe neurological involvement. Recently, many studies in animal models or patients have reported the role of oxidative stress in PKU. In the present work we studied the effect of lipoic acid against oxidative stress in rat brain provoked by an animal model of hyperphenylalaninemia (HPA), induced by repetitive injections of phenylalanine and α-methylphenylalanine (a phenylalanine hydroxylase inhibitor) for 7 days, on some oxidative stress parameters. Lipoic acid prevented alterations on catalase (CAT) and superoxide dismutase (SOD), and the oxidative damage of lipids, proteins, and DNA observed in HPA rats. In addition, lipoic acid diminished reactive species generation compared to HPA group which was positively correlated to SOD/CAT ratio. We also observed that in vitro Phe inhibited CAT activity while phenyllactic and phenylacetic acids stimulated superoxide dismutase activity. These results demonstrate the efficacy of lipoic acid to prevent oxidative stress induced by HPA model in rats. The possible benefits of lipoic acid administration to PKU patients should be considered. 相似文献
45.
Daniela Machado Teresa Baptista Catarina Anjos Susana Mendes Ana Margarete Matias 《Invertebrate reproduction & development.》2013,57(4):179-190
ABSTRACTIn Portugal, the European clam (Ruditapes decussatus) is an important commercial resource. Óbidos Lagoon is a strong candidate as a cultivation area to increase European clam exploitation. However, the reproductive biology of this population has not been described. In this work, the reproductive cycle of R. decussatus was characterized by determining gonadal development stages, gonad index, condition index, and biochemical composition. The relationship between reproduction and environmental parameters (sea surface temperature, chlorophyll a, and particulate organic matter) was assessed. Ruditapes decussatus had an annual reproductive cycle. The gametogenic cycle started in late winter, and the ripe stage in spring was followed by spawning that began at the end of spring/early summer and extended until early autumn. The subsequent period of sexual rest occurred during the winter. Condition index showed seasonal variations related to food availability (chlorophyll a). The European clams in Óbidos Lagoon recovered rapidly after their reproductive period, most likely owing to the availability of food. This study will help to improve sustainable management of this wild stock and is important for future aquaculture development of this species. 相似文献
46.
Luís Roque Noélia Duarte Maria Rosário Bronze Catarina Garcia Julia Alopaeus Jesus Molpeceres 《Biofouling》2013,29(8):880-892
AbstractGlycyrrhiza glabra L. is considered an important source of bioactive compounds. This study aimed at the development of an efficient solution for the treatment of oral candidiasis. Several extracts of Glycyrrhiza glabra L. were prepared using different solvents and their potential in vitro antifungal activity was assessed. Ethanolic extracts showed the most promising results against C. albicans. This extract was incorporated into mucoadhesive nanoparticles (PLA, PLGA and alginate), which were further included in an oral gel, an oral film and a toothpaste, respectively. The results showed that nanoparticles were successfully produced, presenting a mean size among 100–900?nm with high encapsulation efficiency. In vitro studies showed that the most bioadhesive formulation was the oral film with extract-loaded PLGA nanoparticles, followed by the toothpaste with extract-loaded alginate nanoparticles and the oral gel with extract-loaded PLA nanoparticles. 相似文献
47.
Cassandra De Muynck Catarina S. S. Pereira Myriam Naessens Sofie Parmentier Wim Soetaert Erick J. Vandamme 《Critical reviews in biotechnology》2013,33(3):147-171
ABSTRACTThe genus Gluconobacter comprises some of the most frequently used microorganisms when it comes to biotechnological applications. Not only has it been involved in “historical” production processes, such as vinegar production, but in the last decades many bioconversion routes for special and rare sugars involving Gluconobacter have been developed. Among the most recent are the biotransformations involved in the production of L-ribose and miglitol, both very promising pharmaceutical lead molecules. Most of these processes make use of Gluconobacter's membrane-bound polyol dehydrogenases. However, recently other enzymes have also caught the eye of industrial biotechnology. Among them are dextran dextrinase, capable of transglucosylating substrate molecules, and intracellular NAD-dependent polyol dehydrogenases, of interest for co-enzyme regeneration. As such, Gluconobacter is an important industrial microbial strain, but it also finds use in other fields of biotechnology, such as biosensor-technology. This review aims to give an overview of the myriad of applications for Gluconobacter, with a special focus on some recent developments. 相似文献
48.
Nathalia Torres Dutra Vanildo Silveira Inga Gonçalves de Azevedo Lupis Ribeiro Gomes‐Neto Arnoldo Rocha Façanha Neusa Steiner Miguel Pedro Guerra Eny Iochevet Segal Floh Claudete Santa‐Catarina 《Physiologia plantarum》2013,148(1):121-132
Polyamines (PAs) are abundant polycationic compounds involved in many physiological processes in plants, including somatic embryogenesis. This study investigates the role of PAs on cellular growth and structure of pro‐embryogenic masses (PEMs), endogenous PA and proton pump activities in embryogenic suspension cultures of Araucaria angustifolia. The embryogenic suspension cultures were incubated with putrescine (Put), spermidine (Spd), spermine (Spm) and the inhibitor methylglyoxal‐bis(guanylhydrazone) (MGBG), respectively (1 mM). After 24 h and 21 days, the cellular growth and structure of PEMs, endogenous PA contents and proton pump activities were analyzed. The addition of Spm reduced the cellular growth and promoted the development of PEMs in embryogenic cultures, which could be associated with a reduction in the activities of proton pumps, such as H+‐ATPase P‐ and V‐types and H+‐PPases, and alterations in the endogenous PA contents. Spm significantly affected the physiology of the A. angustifolia somatic embryogenesis suspension, as it potentially affects cellular growth and structure of PEMs through the modulation of proton pump activities. This work demonstrates the involvement of exogenous PAs in the modulation of cellular growth and structure of PEMs, endogenous PA levels and proton pump activities during somatic embryogenesis. To our knowledge, this study is the first to report a relationship between PAs and proton pump activities in these processes. The results obtained in this study offer new perspectives for studies addressing the role of PAs and proton pump on somatic embryogenesis in this species. 相似文献
49.
Catarina Prado e Castro José Paulo Sousa María Isabel Arnaldos João Gaspar María Dolores García 《法国昆虫学会纪事》2013,49(1-2):128-139
The first forensic entomological study performed in Portugal is presented. Two piglet (Sus scrofa L.) carcasses were used to determine adult Calliphoridae activity on carrion over a period of 121 days, all along the end of spring and the summer, both in a shaded and a sunny site. Five decomposition stages were observed and a total of 10723 adult Calliphoridae, belonging to 11 species, were collected. Calliphora vicina, Calliphora vomitoria, Chrysomya albiceps and Lucilia caesar were the dominant species in this study. Decomposition was faster on the carcass exposed to the sun and the number of Calliphoridae specimens was higher there than in the shaded site. It was found a significant effect of the decomposition stage in the number of specimens attracted to the carcass, as well as a significant effect of the interaction between the decomposition stage and insolation regime. Calliphora and Lucilia species did not show preference for sunny or shaded areas. Important differences in the Calliphoridae community structure were found compared to other regions of the Iberian Peninsula, reinforcing the need of further studies in different environments and regions of this geographical area in order to collect information about the local necrophagous fauna used in forensic practice. 相似文献
50.
Jaqueline Raymondi Silva Larissa Campos de Medeiros Vinícius Pinho dos Reis Juliana Helena Chávez Thiago Demarchi Munhoz Gustavo Puia Borges Otavio Augusto Brioschi Soares Carlos Henrique Coelho de Campos Rosangela Zacarias Machado Cristiane Divan Baldani Maria Luana Cristiny Rodrigues Silva Joice Lara Maia Faria Edson Elias da Silva Luiz Tadeu Moraes Figueiredo 《Memórias do Instituto Oswaldo Cruz》2013,108(7):921-923
Since the emergence of West Nile virus (WNV) in North America in 1999, there have been several reports of WNV activity in Central and South American countries. To detect WNV in Brazil, we performed a serological survey of horses from different regions of Brazil using recombinant peptides from domain III of WNV. Positive samples were validated with the neutralisation test. Our results showed that of 79 ELISA-positive horses, nine expressed WNV-specific neutralising antibodies. Eight of the infected horses were from the state of Mato Grosso do Sul and one was from the state of Paraíba. Our results provide additional evidence for the emergence of WNV in Brazil and for its circulation in multiple regions of the country. 相似文献