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31.
Caroline de Souza Barros Valeria Garrido Vanessa Melchiades Rafaela Gomes Max Willian Lisboa Gomes Valeria Laneuville Teixeira Izabel Christina Nunes de Palmer Paixão 《Journal of applied phycology》2017,29(2):769-773
Studies with diterpenes from marine brown alga Canistrocarpus cervicornis showed the antiviral potential of the products from this alga in controlling the replication of HSV-1 and maintaining low cytotoxicity. Hence, the aim of this work was to evaluate the anti-herpetic efficacy of C. cervicornis extract ointment in BALB/c mice. To test the anti-herpetic efficacy in vivo, four groups of BALB/c mice (n?=?5) were used: 1—untreated, 2—extract ointment (2 % or 0.4 mg cm?2 dose?1), 3—Acyclovir cream (5 % or 1.0 mg cm?2 dose?1), and 4—ointment base. The right midflank of each mouse was clipped and depilated with a chemical depilatory. After 2 days, the skin area was scratched and inoculated with HSV-1. The ointments and cream were applied three times a day over a 16-day period, beginning 1 h after virus inoculation. The development of skin lesions was continuously monitored and scored. To evaluate the effect of C. cervicornis topical treatment on biochemical parameters and on body weight, two uninfected groups were formed: an untreated group and a group treated with ointment C. cervicornis extract (2 %). The signs of infection appeared from the second day after infection, while on the 10th day of the experiment, the ointment base and untreated groups had significantly more severe lesions than did the groups that were treated with extract (p?<?0.05) or acyclovir (p?<?0,01). The topical application of extract ointment did not change body weight, hepatic, or renal function suggesting that the extract has a low toxicity in this route of administration. These results suggest that the extract may be useful in reducing the severity of HSV-1 cutaneous lesions. 相似文献
32.
Figueiredo Douglas B. Carvalho Eneas Santos Mauricio P. Kraschowetz Stefanie Zanardo Rafaela T. Campani Gilson Silva Gabriel G. Sargo Cíntia R. Horta Antonio Carlos L. de C. Giordano Roberto Miyaji Eliane N. Zangirolami Teresa C. Cabrera-Crespo Joaquin Gonçalves Viviane Maimoni 《Applied microbiology and biotechnology》2017,101(6):2305-2317
Applied Microbiology and Biotechnology - Streptococcus pneumoniae is the main cause of pneumonia, meningitis, and other conditions that kill thousands of children every year worldwide. The... 相似文献
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Gloria Valdes Peter Kaufmann Jenny Corthorn Rafaela Erices K Bridget Brosnihan JaNae Joyner-Grantham 《Reproductive biology and endocrinology : RB&E》2009,7(1):79-20
We postulate that an orchestrated network composed of various vasodilatory systems participates in the systemic and local
hemodynamic adaptations in pregnancy. The temporal patterns of increase in the circulating and urinary levels of five vasodilator
factors/systems, prostacyclin, nitric oxide, kallikrein, angiotensin-(1–7) and VEGF, in normal pregnant women and animals,
as well as the changes observed in preeclamptic pregnancies support their functional role in maintaining normotension by opposing
the vasoconstrictor systems. In addition, the expression of these vasodilators in the different trophoblastic subtypes in
various species supports their role in the transformation of the uterine arteries. Moreover, their expression in the fetal
endothelium and in the syncytiotrophoblast in humans, rats and guinea-pigs, favour their participation in maintaining the
uteroplacental circulation. The findings that sustain the functional associations of the various vasodilators, and their participation
by endocrine, paracrine and autocrine regulation of the systemic and local vasoactive changes of pregnancy are abundant and
compelling. However, further elucidation of the role of the various players is hampered by methodological problems. Among
these difficulties is the complexity of the interactions between the different factors, the likelihood that experimental alterations
induced in one system may be compensated by the other players of the network, and the possibility that data obtained by manipulating
single factors in vitro or in animal studies may be difficult to translate to the human. In addition, the impossibility of
sampling the uteroplacental interface along normal pregnancy precludes obtaining longitudinal profiles of the various players.
Nevertheless, the possibility of improving maternal blood pressure regulation, trophoblast invasion and uteroplacental flow
by enhancing vasodilation (e.g. L-arginine, NO donors, VEGF transfection) deserves unravelling the intricate association of
vasoactive factors and the systemic and local adaptations to pregnancy. 相似文献
35.
Rafaela L. Fogaça Janaína Capelli-Peixoto Isabel B. Yamanaka Rodrigo P. M. de Almeida João Carlos D. Muzzi Mariangela Borges Alvimar J. Costa Carlos Chávez-Olortegui Vanete Thomaz-Soccol Larissa M. Alvarenga Juliana de Moura 《Applied microbiology and biotechnology》2014,98(21):8887-8894
Bovine cysticercosis is detected during the routine post mortem examination of carcasses by visual inspection (knife and eye method). However, the sensitivity of this procedure is several times lower than immunoassays, even when it is performed by qualified professionals. In the present study, a new generation capture antigens were screened from a phage display peptide library using antibodies from Taenia saginata-infected animals. Eight phage clones were selected, and one, Tsag 3 (VHTSIRPRCQPRAITPR), produced similar results to the T. saginata metacestode crude antigen (TsCa) when used as a capture antigen in an ELISA. The phage-displayed peptides competed with TsCa for binding sites, reducing the reactivity by approximately 30 %. Alanine scanning indicated that proline, arginine, and serine are important residues for antibody binding. Tsag 1 (HFYQITWLPNTFPAR), the most frequent affinity-selected clone, and Tsag 6 (YRWPSTPSASRQATL) shared similarity with highly conserved proteins from the Taeniidae family with known immunogenicity. Due to their epitopic or mimotopic properties, these affinity-selected phages could contribute to the rational design of an ante mortem immunodiagnosis method for bovine cysticercosis, as well as an epitope-based vaccine to interrupt the taeniosis/cysticercosis complex. 相似文献
36.
Leonardo Marcel Paiz Lucas Baumgartner Rafaela Maria Moresco Fernando Rodrigo Treco Weferson Júnio da Graça Vladimir Pavan Margarido 《Reviews in Fish Biology and Fisheries》2014,24(1):399-407
Australoheros is represented by species of Cichlidae spread over different Brazilian river systems. Individuals of Australoheros angiru were collected in isolated lagoons at 950 m of altitude in a dividing plateau between the basins of the Iguassu River and the Uruguay River, located in the São Lourenço do Oeste region (Santa Catarina State), and subject to basic and molecular cytogenetic analyzes. Moreover, a review about the occurrence and collections sites of A. angiru was used to the clarification of biogeographical issues of Australoheros and other species of fish that are common between the basins of the Uruguay River and Iguassu River. The analysis by conventional staining with Giemsa found a diploid number of 48 chromosomes (18 submetacentric + 30 subtelocentric/acrocentric) for males and females, without sex chromosome differentiation. The nucleolar organizing regions identified by silver impregnation and by fluorescence in situ hybridization with 18S rDNA probes showed to be simple, located on the end of the short arm of subtelocentric chromosome pair 15. Heterochromatin was observed in the centromeric region of most of the chromosomes of the complement, in addition to coincide with the nucleolar organizing regions. The data presented in this study are the first reports on the location of sites of 5S rDNA for Australoheros, being located in interstitial position on the long arm of subtelocentric chromosome pair 11. The basic and molecular cytogenetic data presented here contribute to the better understanding of chromosomal evolution of Cichlidae, act as interesting tools for taxonomy and phylogeny of the group, in addition to help in understanding the dispersion of A. angiru between the two hydrographic basins. 相似文献
37.
Adriana Silva Lima Rafaela Simão Abrahão Nóbrega Alexandre Barberi Krisle da Silva Daniel Furtado Ferreira Fátima Maria de Souza Moreira 《Plant and Soil》2009,319(1-2):127-145
Understanding native communities is a crucial step for the management of biological nitrogen fixation, since they may be either a source of efficient strains or a limiting factor when efficient strains need to be introduced. This work aimed to evaluate the density, diversity and efficiency of Leguminosae nodulating bacterial (LNB) communities and their component strains in soils under various land use systems (LUSs): pristine forest, agriculture, pasture, agroforestry, young secondary forest, and old secondary forest,. The LNB communities were trapped from these soils by using the promiscuous host siratro under controlled conditions. We also studied their relationships with physical and chemical attributes of the soil. Agroforestry and agriculture soil samples induced the highest number of nodules in siratro, while forest soil samples induced the lowest number of nodules. No relationship was found between LNB and Leguminosae species diversity in the LUSs. The soil chemical variables that were most related to differences in nodule number and shoot dry matter weight of plants inoculated with soil suspensions of the LUSs were, respectively: Ca2+, Mg2+, base saturation, exchangeable bases and Cu2+; and pH, cation exchange capacity, B, Cu2+ and clay. Although, LNB communities from all LUSs were efficient under controlled and similar conditions, they were found to be composed of strains with variable efficiency: inefficient, efficient, highly efficient and superior efficiency. Efficient strains occurred at the highest frequency in all LUSs. The isolated strains presented similar and new sequences that were phylogenetically related to well known LNB genera in α-and β-Proteobacteria. Unusual genera in these branches, as well as in other branches, which are probably endophytic bacteria, were also isolated from nodules. These data support siratro as a useful trap species to study the LNB biodiversity of diverse ecosystems in tropical soils. The fact that the highest diversity and nodulation were seen in managed systems such as agriculture and agroforestry suggests a high resilience of LNB communities to changes in land use after deforestation in a region where large forest areas are still preserved and can be a source of propagules. 相似文献
38.
Honest error,precaution or alertness advertisement? Reactions to vertebrate pseudopredators in red‐nosed cuxiús (Chiropotes albinasus), a high‐canopy neotropical primate
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Adrian A. Barnett Tadeu de Oliveira Rafaela Fatima Soares da Silva Samara de Albuquerque Teixeira Pavel Tomanek Lucy M. Todd Sarah A. Boyle 《Ethology : formerly Zeitschrift fur Tierpsychologie》2018,124(3):177-187
Predation on primates is considered to have far‐reaching effects on the foraging and social ecology of a species. Primate species display a variety of responses to predator proximity and attack, ranging from active physical defense and mobbing, to flight and concealment. Warning calls are often given, and potentially threatening animals may be tracked, either actively or with head movements. Such behaviors take time that could be used for other activities. Accordingly, there should be strong selection to respond only to those species that represent a genuine threat. However, primates give defense‐based behaviors to non‐predator species. We tested the hypotheses that responses to pseudopredators are (i) precautionary calls made by individuals following the Dinner/Life Principle, or (ii) represent the ontogeny of species recognition. Of the species that ellicted a response from the cuxiús, 80% resembled a primate predator; 95% of the encounters that elicited a response from the cuxiús occurred when the distance between the pseudopredator and cuxiús was ≤20 m. In regard to the frequency of responses to pseudopredators, we found no difference between adults and juveniles (47.6% and 52.4%, respectively) and no differences between adult males and adult females (60% and 40% of the responses, respectively). However, reactions to pseudopredators were of shorter duration ( ± standard error (SE): 42.2 ± 15.9 s) than were reactions to actual predator species ( ± SE: 1,024.3 ± 329.1 s). There were only three instances where alarm calls were made to species that did not resemble predators, and 66.7% (N = 2) were made by adult cuxiús and only 33.3% (N = 1) were made by a juvenile cuxiú. Therefore, we found partial support for the Dinner/Life Principle hypothesis, but no support for the ontogeny hypothesis. Examination of such responses to pseudopredators in other primate and non‐primate species may help understand the evolution of such behaviors. 相似文献
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40.
Rafael Gomes Barbosa-Silva Paulo Henrique Labiak André Dos Santos Bragança Gil Renato Goldenberg Fabian A. Michelangeli Gustavo Martinelli Marcus A. Nadruz Coelho Daniela C. Zappi Rafaela Campostrini Forzza 《Brittonia》2016,68(4):397-408
The Guayana Shield is one of the oldest geological formations in South America, ranging from southern Colombia, Venezuela, and the Guianas to the extreme north of the Brazilian states of Amazonas and Roraima. Because of its ancient origin and isolation from other mountain ranges in South America, it harbors a rich flora with high levels of endemism. Recent expeditions to remote areas in the Brazilian portion of the Guayana Shield generated many new herbarium collections. Through these efforts, we report the first records for Brazil of 57 species and infraspecific taxa of vascular plants. In most cases, the taxa are narrowly distributed and were previously known from nearby populations in other countries. In other cases, however, the new Brazilian records expand considerably the known geographical distributions of the taxa. 相似文献