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排序方式: 共有5970条查询结果,搜索用时 26 毫秒
1.
Kozue Akamine Keiko Mekaru Keiya Gibo Chinatsu Nagata Rie Nakamura Sugiko Oishi Maho Miyagi Chiaki Heshiki Yoichi Aoki 《Reproductive Medicine and Biology》2021,20(1):76-82
PurposeTo investigate impact of the one‐carbon metabolism (OCM) on oocyte maturity and embryo development.MethodsThis prospective study analyzed 18 women who agreed to participate. We measured the OCM biomarkers’ concentrations including Vitamin B12 (VB12), folic acid (FA), and homocysteine (Hcy) in serum and follicular fluid (FF), and assessed their correlation. We also evaluated the influence of such OCM biomarker concentrations in mono‐FF on oocyte maturation, fertilization, embryo quality, and consequent pregnancy after embryo transfers.ResultsAll biomarkers showed a high concentration variability in different follicles of each woman, but their mean levels correlated with the serum levels. Among the 106 collected oocytes, 92 were mature, 59 were fertilized, and 16 yielded good‐quality embryos. We performed 26 single embryo transfers, and 7 patients achieved clinical pregnancies. VB12 concentration (FF) was significantly lower in fertilized than unfertilized oocytes by univariate analysis. In multivariate logistic analysis, a significant correlation was found between FA concentration (FF) <14.25 ng/mL and good‐quality embryos and between Hcy concentration (FF) <4.9 nmol/mL and clinical pregnancy.ConclusionOCM in FF may affect fertilization, embryo quality, and clinical pregnancy. 相似文献
2.
《Vaccine》2021,39(14):1933-1942
The genetic and antigenic drift associated with the high pathogenicity avian influenza (HPAI) viruses of Goose/Guangdong (Gs/GD) lineage and the emergence of vaccine-resistant field viruses underscores the need for a broadly protective H5 influenza A vaccine. Here, we tested experimental vector herpesvirus of turkey (vHVT)-H5 vaccines containing either wild-type clade 2.3.4.4A-derived H5 inserts or computationally optimized broadly reactive antigen (COBRA) inserts with challenge by homologous and genetically divergent H5 HPAI Gs/GD lineage viruses in chickens. Direct assessment of protection was confirmed for all the tested constructs, which provided clinical protection against the homologous and heterologous H5 HPAI Gs/GD challenge viruses and significantly decreased oropharyngeal shedding titers compared to the sham vaccine. The cross reactivity was assessed by hemagglutinin inhibition (HI) and focus reduction assay against a panel of phylogenetically and antigenically diverse H5 strains. The COBRA-derived H5 inserts elicited antibody responses against antigenically diverse strains, while the wild-type-derived H5 vaccines elicited protection mostly against close antigenically related clades 2.3.4.4A and 2.3.4.4D viruses. In conclusion, the HVT vector, a widely used replicating vaccine platform in poultry, with H5 insert provides clinical protection and significant reduction of viral shedding against homologous and heterologous challenge. In addition, the COBRA-derived inserts have the potential to be used against antigenically distinct co-circulating viruses and future drift variants. 相似文献
3.
目的:探讨二补助育汤对胚胎着床障碍模型小鼠子宫内膜形态及血管生成素-1(Ang-1)mRNA、血管内皮生长因子(VEGF)mRNA的表达和定位的影响。方法:24只ICR雌性小鼠随机分为空白组、模型组、戊酸雌二醇组、二补助育汤组,每组6只,用米非司酮建立胚胎着床障碍动物模型,各组给予相应药物灌胃,妊娠第5天处死小鼠后,检测各组妊娠率、平均着床位点数、子宫内膜Ang-1和VEGF mRNA表达量及其蛋白定位。结果:模型组小鼠平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量明显低于空白组(均P<0.05);与模型组比较,二补助育汤组平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量显著提高(均P<0.05)。结论:二补助育汤可提高子宫内膜Ang-1和VEGF蛋白表达量,促进子宫内膜血管生成,从而提高子宫内膜容受性。 相似文献
4.
Embryo aneuploidies may be responsible for implantation failures, miscarriages and affects IVF outcomes. A variety of technologies have been implemented to individuate euploid embryos in IVF treatments, which is named preimplantation genetic testing for aneuploidies (PGT-A). According to this strategy, a better embryo selection should increase IVF results. In reality, several issues remain unaddressed including the sampling strategy, involving the test outcomes, and the frequent occurrence of embryo mosaicism, affecting the criteria for selection of supposed viable embryos and possibly posing an ethical dilemma. Safety issues are in place, including perinatal and postnatal consequences of embryo sampling and the epigenetic weaknesses from a prolonged in vitro culture, necessary for trophectoderm biopsy. On the other side, chromosome number mistakes are progressively recognized as physiologic events in the early pre-implantation embryo with many corrective mechanisms in place and their destiny in the post-implantation development is unclear. Accordingly, the increasing precision of the diagnostic tools should be used to investigate the effect of such interventions within rigorous research programs in the sake of improved clinical outcomes. Meantime the diagnosis of embryo aneuploidies in IVF cycles should be considered as a research tool and systematic implementation in clinical practice may appear unjustified. 相似文献
5.
In this study, we report the antioxidant and antitoxic potential of chemically synthesized 4-oxo-2-phenyl-4H-chromene-7,8-diyl bis((1-amino-2-hydroxypropyl)carbamate) (DHF-BAHPC) compound using in vitro and in vivo assays. The DHF-BAHPC was synthesized by linking 7,8-Dihydroxyflavone (DHF) with two molecules of Fmoc-threonine and characterized by Ultraviolet-visible spectroscopy (UV–vis), Fourier-transform infrared spectroscopy (FT-IR), 1H NMR, 13C NMR and Mass spectrometry (MS). In vitro, antioxidant assay results revealed that DHF-BAHPC has a dose-dependent radical scavenging potential towards DPPH, ABTS, FRAP and H2O2 radicals with an IC50 range of 15.45, 66.27, 25.71, 4.375 μg/mL, respectively. Furthermore DHF-BAHPC treatment significantly altered cadmium (Cd) intoxicated zebrafish embryos by rescuing the developmental changes associated with severe histological and reduced the level of defensive antioxidant activities (SOD, CAT, GPx and GST). The overall results of the present study represented that DHF-BAHPC may be used as a potential drug in redox-based therapeutics. 相似文献
6.
Ali Buran Pinar Tulay Nurten Dayolu Mustafa Emre Bakircioglu Mustafa Bahceci Tulay rez 《Andrologia》2019,51(4)
Low sperm quality has negative effects on fertilisation and embryo development. The males with azoospermia apply for testicular sperm extraction (TESE) or microsurgical epididymal sperm aspiration (MESA) in order to retrieve sperm. To date, there have not been any reports investigating morphokinetic parameters of pre‐implantation embryos using testicular and epididymal spermatozoa. Therefore, we aimed to correlate embryo development and assess morphogenetic parameters in embryos obtained by TESE and MESA using time‐lapse imaging. A total of 60 patients undergoing IVF treatments were included in this study. Twenty men with normal semen parameters were selected as control group. Twenty men undergoing TESE and 20 men undergoing MESA were also included in this study. The morphokinetic parameters of time intervals between the second polar body (PB2) extrusion, pronuclei formation and disappearance and cleavage divisions showed significant variations in TESE, MESA and control groups. Furthermore, the pregnancy rates (positive beta‐hCG) were shown to be similar in both TESE and the control group (55% in each group), whereas for the MESA group, this rate was significantly lower (39%, p = 0.049). Further extrapolation of these results may implicate that the obstructive azoospermia patients should undergo TESE instead of MESA for better blastocyst development and higher pregnancy rates. 相似文献
7.
《Vaccine》2020,38(6):1526-1534
Despite decades of vaccination, surveillance, and biosecurity measures, H5N2 low pathogenicity avian influenza (LPAI) virus infections continue in Mexico and neighboring countries. One explanation for tenacity of H5N2 LPAI in Mexico is the antigenic divergence of circulating field viruses compared to licensed vaccines due to antigenic drift. Our phylogenetic analysis indicates that the H5N2 LPAI viruses circulating in Mexico and neighboring countries since 1994 have undergone antigenic drift away from vaccine seed strains. Here we evaluated the efficacy of a new recombinant fowlpox virus vector containing an updated H5 insert (rFPV-H5/2016), more relevant to the current strains circulating in Mexico. We tested the vaccine efficacy against a closely related subcluster 4 Mexican H5N2 LPAI (2010 H5/LP) virus and the historic H5N2 HPAI (1995 H5/HP) virus in White Leghorn chickens. The rFPV-H5/2016 vaccine provided hemagglutinin inhibition (HI) titers pre-challenge against viral antigens from both challenge viruses in almost 100% of the immunized birds, with no differences in number of birds seroconverting or HI titers among all tested doses (1.5, 2.0, and 3.1 log10 mean tissue culture infectious doses/bird). The vaccine conferred 100% clinical protection and a significant decrease in oral and cloacal virus shedding from 1995 H5/HP virus challenged birds when compared to the sham controls at all tested doses. Virus shedding titers from vaccinated 2010 H5/LP virus challenged birds significantly decreased compared to sham birds especially at earlier time points. Our results confirm the efficacy of the new rFPV-H5/2016 against antigenic drift of LPAI virus in Mexico and suggest that this vaccine would be a good candidate, likely as a primer in a prime-boost vaccination program. 相似文献
8.
《Anales de pediatría (Barcelona, Spain : 2003)》2020,92(4):200-207
IntroductionMore than five million children have been conceived by assisted reproductive techniques (ART) around the world. Most authors agree that there are no differences in psychomotor development in comparison to naturally conceived children. However, these results are still contradictory.ObjectiveTo determine whether children born from a cohort of ART-clinical gestations have a higher risk of suffering neurodevelopmental disorders in comparison to a control group. The potential associated ART-factors associated were also determined.Material and methodsThe study included the assessment of children up to 3 years old conceived by ART, and born from a cohort of women treated by the reproduction unit of a public hospital from May 2012 to May 2014. A simultaneous assessment was made of matched controls, by following the newborn naturally conceived after the ART-case, of the same group of maternal age, gestational age, and type of gestation.ResultsThere were 243 clinical gestations and 267 ART-newborns, of which 231 were assessed (87%). A simultaneous assessment was carried out in 208/230 controls (90%). There were no differences in neurodevelopmental disorders (global developmental delay, autism spectrum or language delay). Multivariate analysis of potential ART factors only showed an association between transfer of frozen embryos with language delay that has not been previously described.ConclusionsThere were no differences between groups after adjusting the results according to maternal age, multiple pregnancy, and other possible confounding factors, supporting that the role of these factors may be more relevant than the ART itself. The association between frozen embryo transfer and language delay has not been previously described. Thus, more studies are needed to confirm or refute this relationship. 相似文献
9.
The escalating demand for fipronil by the increasing insects’ resistance to synthetic pyrethroids placed a burden on aquatic vertebrates. Although awareness regarding the toxicity of fipronil to fish is arising, the integral alteration caused by fipronil remains unexplored. Here, we investigated on the development toxicity of fipronil and the metabolic physiology perturbation at 120 h post fertilization through GC–MS metabolomics on zebrafish embryo. We observed that fipronil dose-dependently induced malformations including uninflated swim bladder and bent spine. Further, the “omic” technique hit 26 differential metabolites after exposure to fipronil and five significant signaling pathways. We speculated that changes in primary bile acid synthesis pathway and the content of saturated fatty acid in the chemical-related group indicated the liver toxicity. Pathway of Aminoacyl-tRNA biosynthesis changed by fipronil may relate to the macromolecular synthesis. Concurrently, methane metabolism pathway was also identified while the role in zebrafish needs further determination. Overall, this study revealed several new signaling pathways in fipronil-treated zebrafish embryo/larval. 相似文献
10.
E. A. Kalinina A. V. Malushko T. M. Zubareva S. I. Sitkin T. S. Sheveleva 《Gynecological endocrinology》2015,31(10):79-82
AbstractNowadays, the reproductive medicine has started to develop precipitously. Nevertheless, 60 to 80 millions of couples worldwide suffer from infertility. The etiology and pathogenesis of many diseases leading to infertility is still causing a lot of debates and needs to be researched further. In 25% of the cases, the cause of infertility may not be identified that forces couples to seek help in auxiliary reproductive technologies. However, even in this case the probability of a positive result makes up no more than 40%. In recent years, scientists' attention became increasingly driven to the so-called omics-disciplines, including metabolomics. Many researchers believe that metabolomics is that science which will give a possibility to improve the quality of diagnosis, will lead to a deeper understanding of the etiology and pathogenesis of diseases that lead to infertility and will improve the quality of the assessment of oocytes and embryos in IVF cycles. 相似文献