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31.

Purpose

In contrast to most other mammals, canine oocytes are ovulated in an immature state and undergo oocyte maturation within the oviduct during the estrus stage. The aim of the study was to investigate whether oviduct cells from the estrus stage affect the maturation of oocytes and show gene expression patterns related to oocyte maturation.

Methods

We analyzed MAPK1/3, SMAD2/3, and BMP6/15 expression in oviduct cells, cumulus cells, and oocytes from anestrus, estrus, and diestrus stages. Next, we investigated the effect of co-culture with oviduct cells derived from the estrus stage upon in vitro maturation (IVM) of canine oocytes.

Results

There was significantly higher MAPK1/3 (1.42 ± 0.02 and 2.23 ± 0.06), SMAD2/3 (0.77 ± 0.03 and 2.39 ± 0.07), and BMP15 (2.21 ± 0.16) expression in oviduct cells at the estrus stage (P < 0.05). In cumulus cells, MAPK1 (1.26 ± 0.07), SMAD2/3 (0.82 ± 0.01, 1.04 ± 0.01), and BMP6 (13.09 ± 0.11) expression was significantly higher in the estrus stage (P < 0.05). In oocytes, significant upregulation of MAPK1/3 (14,960 ± 3121 and 1668 ± 253.4), SMAD3 (774.6 ± 79.62), and BMP6 (8500 ± 895.4) expression was found in the estrus stage (P < 0.05). After 72 h of IVM culture, a significantly higher maturation rate was observed in oocytes co-cultured with oviduct cells (10.0 ± 1.5%) than in the control group (3.2 ± 1.4%).

Conclusions

We demonstrate that oviduct cells at the estrus stage highly expressed MAPK1/3, SMAD2/3, and BMP15. Furthermore, canine oviduct cells from the estrus stage enhance the culture environment for canine oocyte maturation.
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Terahertz (THz) irradiation of excised Eisenia andrei earthworms is shown to cause overriding of the genetically determined, endogenously mediated segment renewing capacity of the model animal. Single-cycle THz pulses of 5 µJ energy, 0.30 THz mean frequency, 293 kV/cm peak electric field, and 1 kHz repetition rate stimulated the cell proliferation (indicated by the high number of mitotic cells) and both histogenesis and organogenesis, producing a significantly higher number of regenerated segments. The most conspicuous alteration in THz-treated animals was the more intense development of the new central nervous system and blood vessels. These results clearly demonstrate that THz pulses are capable to efficiently trigger biological processes and suggest potential applications in medicine.  相似文献   
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Hematite (α-Fe2O3) with uniform hexagonal flake morphology has been successfully synthesized using a combination of gelatin as natural template with F127 via hydrothermal method. The resulting hematite was investigated as adsorbent and photocatalyst for removal of ibuprofen as pharmaceutical waste. Hexagonal flake-like hematite was obtained following calcination at 500 °C with the average size was measured at 1–3 µm. Increasing the calcination temperature to 700 °C transformed the uniform hexagonal structure into cubic shape morphology. Hematite also showed high thermal stability with increasing the calcination temperatures; however, the surface area was reduced from 47 m2/g to 9 m2/g. FTIR analysis further confirmed the formation Fe-O-Fe bonds, and the main constituent elements of Fe and O were observed in EDX analysis for all samples. α-Fe2O3 samples have an average adsorption capacity of 55–25.5 mg/g at 12–22% of removal efficiency when used as adsorbent for ibuprofen. The adsorption capacity was reduced as the calcination temperatures increased due to the reduction of available surface area of the hexagonal flakes after transforming into cubes. Photocatalytic degradation of ibuprofen using hematite flakes achieved 50% removal efficiency; meanwhile, combination of adsorption and photocatalytic degradation further removed 80% of ibuprofen in water/hexane mixtures.  相似文献   
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The activity of mesoporous Al-MCM-41 for deoxygenation of Reutealis trisperma oil (RTO) was enhanced via modification with NiO nanoparticles. Deoxygenation at atmospheric pressure and under H2 free conditions required acid catalysts to ensure the removal of the oxygenated fragments in triglycerides to form liquid hydrocarbons. NiO at different weight loadings was impregnated onto Al-MCM-41 and the changes of Lewis/Brønsted acidity and mesoporosity of the catalysts were investigated. The activity of Al-MCM-41 was enhanced when impregnated with NiO due to the increase of Lewis acidity originating from NiO nanoparticles and the mesoporosity of Al-MCM-41. Increasing the NiO loading enhanced the Lewis acidity but not Brønsted acidity, leading to a higher conversion towards liquid hydrocarbon yield. Impregnation with 10% of NiO on Al-MCM-41 increased the conversion of RTO to hydrocarbons via the deoxygenation pathway and reduced the products from cracking reaction, consequently enhancing the green diesel (C11–C18) hydrocarbon products.

The activity of mesoporous Al-MCM-41 for deoxygenation of Reutealis trisperma oil (RTO) was enhanced via modification with NiO nanoparticles.  相似文献   
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The role of nutritional factors in arsenic metabolism and toxicity is not clear. Provision of certain low protein diets resulted in decreased excretion of DMA and increased tissue retention of arsenic in experimental studies. This paper reports a prevalence comparison study conducted in Bangladesh to assess the nutritional status among the chronic arsenic exposed and unexposed population. 138 exposed individuals diagnosed as arsenicosis patients were selected from three known arsenic endemic villages of Bangladesh and age, sex matched 144 unexposed subjects were randomly selected from three arsenic free villages. The mean arsenic concentration in drinking water for the exposed and unexposed population was 641.15 and 13.5 microg L(-1) respectively. Body Mass Index was found to be lower than 18.5, the cut off point for malnutrition, in 57 (41.31%) out of 138 exposed arsenicosis cases and 31 (21.53%) out of 144 unexposed individuals. The crude prevalence ratio (or risk) was 1.92 (95% CI = 1.33-2.78) for poor nutritional status among the arsenicosis cases compared to the unexposed population. The findings of this study add to the evidence that poor nutritional status may increase an individual's susceptibility to chronic arsenic toxicity, or alternatively that arsenicosis may contribute to poor nutritional status.  相似文献   
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