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151.
Tiago S. Nascimento Isabelle S. M. Silva Maria Cecília M. A. Alves Bruna B. Gouveia Lara Mariane R. Barbosa Taís J. S. Macedo Jamile M. S. Santos Alane P. O. Monte Maria Helena T. Matos Francine F. Padilha Isabel B. Lima‐Verde 《Reproduction in domestic animals》2019,54(1):31-38
This study aimed to characterize the hydroethanolic extract of red propolis (HERP) and nanoparticles containing HERP for using as an additive in the culture medium of isolated ovine preantral follicles. HERP was characterized by high‐performance liquid chromatography (HPLC) and determination of flavonoid content, and the nanoparticles by the mean particle diameter, polydispersity index (PI) and encapsulation efficiency (EE). The effect of HERP (10 and 20 ηg/ml—HERP10 and HERP20 groups) and nanoparticles (NP10 and NP20 groups) on isolated secondary follicles cultured in vitro for 12 days was observed by morphological evaluation, oxidative stress markers (reactive oxygen species—ROS and glutathione—GSH) and active mitochondria. HPLC showed formononetin as the major compound in the HERP (63.92 ± 0.21 μg/mL). The content of flavonoids ranged from 2.14% to 11.00%. The nanoparticles showed mean diameter of 287.5 ± 3.9 and 479 ± 18.1 ηm; PI of 0.117 ± 0.018 and 0.316 ± 0.039; and EE of 67.15% and 41%, respectively, for the NP10 and NP20 groups. After 12 days of culture, HERP20 and NP20 increased (p < 0.05) the percentage of normal follicles compared to NP10. HERP20 showed significantly higher percentages of antrum formation than control medium (MEM) and NP10 (p < 0.05). HERP20 also showed an increase (p < 0.05) in mitochondrial activity compared to the other treatments, except NP20 (p > 0.05), and increased GSH levels (p < 0.05) compared to MEM and HERP10. In conclusion, use of HERP (20 ηg/ml) on in vitro culture of isolated ovine preantral follicles can increase antrum formation, mitochondrial activity and GSH levels. 相似文献
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154.
Gabriela de Oliveira Fernandes Camila Bruna de Lima Andrei Antonioni Guedes Fidelis Marcella Pecora Milazzotto Margot Alves Nunes Dode 《Reproduction in domestic animals》2023,58(1):117-128
In the present study, we investigated the spent culture media of in vitro produced (IVP) bovine embryos which did (group Pregnant) or did not (group Non-pregnant) establish pregnancy after transfer. For that purpose, IVP embryos on D5 were transferred to individual droplets for the last 48 h of culture. Embryos at the blastocyst stage were then transferred to synchronized recipients, while respective culture media drops were collected and evaluated individually. The list of metabolites present in spent culture media was obtained by electrospray ionization mass spectrometry (ESI-MS) and analysed with Metaboanalyst® to characterize the metabolic profile of each group. The spectrometric analysis showed that pathways related to lipid metabolism, particularly fatty acids degradation via beta-oxidation, were more present in the Pregnant group whereas no significant pathway was identified in the group Non-pregnant. By using this method, we were able to identify a metabolic signature in culture media that allows for a better comprehension of preferential metabolic routes taken by the most viable embryos. These findings offer great insights into the biochemistry of embryo development and reveal a potential target for the development of better-quality IVP systems, as well as tools to identify bovine embryos with greater chances to establish and maintain pregnancy. 相似文献
155.
Pessoa OD de Carvalho CB Silvestre JO Lima MC Neto RM Matos FJ Lemos TL 《Fitoterapia》2005,76(7-8):712-714
The essential oil of fresh leaves of Lippia aff. gracillis was analyzed by GC/MS and evaluated for its antibacterial effects. The results showed a moderate antibacterial activity and confirm the traditional uses of L. aff. gracillis. 相似文献
156.
Wood specific gravity was determined for 29 half-sib families of 4-year-old Pinus tecunumanii from the Mountain Pine Ridge, Belize, planted at three locations in Brazil and Colombia. Although there was a significant (p 0.05) family by sites interaction (F × S), it was found that only 5 of the 29 families were major contributors. The test planting at the highest elevation (1750 m, La Arcadia, Colombia) was the most interactive site.CAMCORE Cooperative, College of Forest Resources, North Carolina State University 相似文献
157.
Antinociceptive activity of the pyranocoumarin seselin in mice 总被引:1,自引:0,他引:1
Lima V Silva CB Mafezoli J Bezerra MM Moraes MO Mourão GS Silva JN Oliveira MC 《Fitoterapia》2006,77(7-8):574-578
Seselin an angular pyranocoumarin at dose of 0.5, 4.5 or 40.5 mg/kg inhibited the writhing response induced by acetic acid in a significant and dose-dependent manner, by 19.5%, 26.2% and 41.4%, respectively. Using the same doses, seselin elicited a significant inhibition of formalin response during the second phase (inflammatory), by 90.3%, 97.8% and 95.3%, respectively. Besides, a significant reduction of licking time was observed during the first phase (neurogenic) at the highest doses of seselin, by 34.4% and 66.9%, respectively. On the contrary, in the hot plate test no effect was observed after seselin treatment. In conclusion, seselin was able to inhibit inflammatory hyperalgesia, suggesting that this natural product possesses both important peripheral anti-inflammatory and antinociceptive properties. 相似文献
158.
de Avila LF Conceição FR Telmo Pde L Dutra GF de los Santos DG Martins LH Berne ME da Silva PE Scaini CJ 《Veterinary parasitology》2012,187(1-2):337-340
Several studies have shown the benefit of the use of probiotics in the prevention and treatment of diseases; however, few of them have investigated the effect of probiotics on parasitosis. In this study, the effect of Saccharomyces boulardii on the intensity of infection of mice with toxocariasis was evaluated. The animals were fed with a diet supplemented with S. boulardii for 15 days before inoculation with Toxocara canis eggs and for 2 or 60 days post-inoculation. S. boulardii promoted a reduction of approximately 36% in the average number of recovered T. canis larvae, suggesting that it can be used as an alternative to help control toxocariasis. 相似文献
159.
Schuindt SH Oliveira BC Pimentel PM Resende TL Retamal CA DaMatta RA Seipel D Arnholdt AC 《Veterinary parasitology》2012,186(3-4):207-215
Toxoplasmosis is a world wide spread zoonosis caused by Toxoplasma gondii, an obligate intracellular parasite that is able to disseminate into deep tissues and cross biological barriers, reaching immunoprivileged sites such as the brain and retina. The parasite is able to infect macrophages and dendritic cells for dispersal throughout the body. However, the molecular mechanisms or outcomes of the subversion of the host cell are largely unknown. Recently our group established that metalloproteinases are involved in migration of infected macrophages. Herein, we evaluated the recruitment of host invasive machinery components in T. gondii infected murine macrophages. We showed by immunoprecipitation assays that MMP-9, CD44 TIMP-1 and uPAR were secreted as a multi-protein complex by infected macrophages. Zymographic analysis revealed that MMP-9 was present in its pro- and active form. Moreover, inhibition of uPA/uPAR pathway by PAI-1 decreased secretion of MMP-9 active forms, as well those associated to uPAR and TIMP-1, but not to CD44. Data presented here suggest that MMP-9 is secreted as a multiprotein complex by T. gondii infected macrophages, similar to that observed in metastatic cells. We further speculate that uPA/uPAR system is involved in the expression/secretion of complexes containing active MMP-9 forms. 相似文献
160.
Richard S. Taylor Joel Slinger Paula Camargo Lima Chloe J. English Ben T. Maynard Francisca Samsing Russell McCulloch Petra R. Quezada‐Rodriguez James W. Wynne 《Aquaculture Research》2021,52(1):117-129
Amoebic gill disease (AGD), caused by Neoparamoeba perurans, is a major health challenge for Atlantic salmon aquaculture globally. While freshwater bathing for 2 hr is effective in reducing infection severity, there is need for more rapid and lower cost alternatives. To this end, a combination of sodium percarbonate (SPC) in freshwater was examined for its treatment efficacy. Initial in vitro studies showed a reduction in amoeba viability when exposed for 30 min to freshwater containing >500 mg/L SPC. Subsequently, AGD‐affected salmon were bathed for 30 min in 16°C freshwater containing 100, 500 or 1,000 mg/L SPC, or for 2 hr in 16°C freshwater to mimic industry practice. Treatment at the highest SPC concentration caused extensive gill damage and substantial mortality. Neither occurred to a significant extent at lower SPC concentrations. Gill pathology of surviving fish 10 days post‐treatment (dpt) was comparable to or more severe than pre‐treatment, and significantly (p < .001) more severe than in 2 hr freshwater bathed fish. N. perurans DNA was confirmed by qPCR in all treatment groups at 10 dpt. The data indicate that a 30‐min exposure to SPC in freshwater is not a suitable alternative to existing freshwater treatment of AGD. 相似文献