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221.
Optimal Predictive Control of Three-Phase NPC Multilevel Converter for Power Quality Applications 总被引:1,自引:0,他引:1
222.
Infertility represents a major clinical problem and 50% of cases are attributable to the male partner. Testicular function is temperature dependent, and in both man and mouse the position of the testes in the scrotum ensures that they are kept at between 2 and 8 degrees C below core body temperature. We used a mouse model to investigate the impact of a single, transient, mild, scrotal heat stress (38, 40 or 42 degrees C for 30 min) on testicular function, sperm DNA integrity and embryo survival. We detected temperature-dependent changes in testicular architecture, number of apoptotic cells and a significant reduction in testis weight 7 and 14 days after heat stress at 42 degrees C. We report for the first time that DNA strand breaks (gamma-H2AX-positive foci) were present in spermatocytes recovered from testes subjected to 40 or 42 degrees C. Fertility of heat-stressed males was tested 23-28 d after treatment (sperm at this time would have been spermatocytes at time of heating). Paternal heat stress at 42 degrees C resulted in reduced pregnancy rate, placental weight and litter size; pregnancies from the 40 degrees C group had increased resorptions at e14.5. Abnormalities in embryonic development were detected at e3.5 and in vitro fertilisation with sperm recovered 16 h or 23 d after scrotal stress at 42 degrees C revealed a block in development between the 4-cell and blastocyst stages. This study has provided evidence of temperature-dependent effects on germ cell DNA integrity and highlighted the importance of an intact paternal genome for normal embryo development. 相似文献
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Olga Soares do Rêgo Barros Francielle Rodrigues Silva Vanessa Loren Nunes 《Journal of Sulfur Chemistry》2019,40(1):9-17
We reported the synthesis of copper (I)-selenophene-2-carboxylate (CuSC) and application as new catalyst in the cross-coupling reactions of thiols with aryl iodide to afford the corresponding unsymmetrical thioethers. The optimized reaction conditions were applied to thiols and aryl iodides having a wide range of functional groups, including electron rich and electron poor substrates. The chemoselectivity of the reaction with 4-iodobromobenzene and 2-aminothiophenol derivatives was briefly examined through the competitive iodine versus bromine and thiol versus nitrogen cross-coupling. 相似文献
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Structured biopolymer-based delivery systems for encapsulation,protection, and release of lipophilic compounds 总被引:1,自引:0,他引:1
Food-grade biopolymers, such as proteins and polysaccharides, can be used to create a diverse range of delivery systems suitable for encapsulating, protecting, and delivering lipophilic functional components, such as ω-3 rich oils, conjugated linoleic acid (CLA), oil-soluble vitamins, flavors, colors, and nutraceuticals. This article provides an overview of a number of different approaches that can be used to create structured delivery systems based on biopolymers, including molecular complexation, coacervation, thermodynamic incompatibility, moulding, and extrusion methods. These delivery systems can be produced from food-grade ingredients using simple processing operations (e.g., mixing, homogenizing, and thermal processing). The structure, production, performance, and potential applications of each type of structured delivery system are discussed. 相似文献
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de Souza Junior Jonas Pereira Frazão Joaquim José de Morais Thais Chagas Barros Espoti Clara Degli dos Santos Sarah Marcilene Machado de Mello Prado Renato 《SILICON》2021,13(4):1269-1275
Silicon - Silicon (Si) combined with foliar spraying of salicylic acid (SA) can affect the absorption of this beneficial element. A study with Si non-accumulators plants (soybean and bean) observed... 相似文献
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Matthew Thomas Ferreira Juliano Andreoli Miyake Renata Nascimento Gomes Fbio Feitoza Pollyana Bulgarelli Stevannato Andrew Silva da Cunha Fernanda de Oliveira Serachi Alexandros Theodoros Panagopoulos Alison Colquhoun 《International journal of molecular sciences》2021,22(9)
Prostaglandin E2 (PGE2) is known to increase glioblastoma (GBM) cell proliferation and migration while cyclooxygenase (COX) inhibition decreases proliferation and migration. The present study investigated the effects of COX inhibitors and PGE2 receptor antagonists on GBM cell biology. Cells were grown with inhibitors and dose response, viable cell counting, flow cytometry, cell migration, gene expression, Western blotting, and gelatin zymography studies were performed. The stimulatory effects of PGE2 and the inhibitory effects of ibuprofen (IBP) were confirmed in GBM cells. The EP2 and EP4 receptors were identified as important mediators of the actions of PGE2 in GBM cells. The concomitant inhibition of EP2 and EP4 caused a significant decrease in cell migration which was not reverted by exogenous PGE2. In T98G cells exogenous PGE2 increased latent MMP2 gelatinolytic activity. The inhibition of COX1 or COX2 caused significant alterations in MMP2 expression and gelatinolytic activity in GBM cells. These findings provide further evidence for the importance of PGE2 signalling through the EP2 and the EP4 receptor in the control of GBM cell biology. They also support the hypothesis that a relationship exists between COX1 and MMP2 in GBM cells which merits further investigation as a novel therapeutic target for drug development. 相似文献