紫外照射对留胚米稳定性的影响

为了提高留胚米的稳定性,采用紫外照射对留胚米进行稳定化处理。采用单因素实验及响应面分析研究紫外照射对留胚米脂肪酶灭活率的影响,同时考察留胚米水分损失率、碎米率和爆腰率的变化。结果表明：紫外照射最佳条件是照射时间11.50min,照射距离为4.5cm,初始水分含量13%,此时脂肪酶灭活率66.73%、且碎米率增加0.12%、爆腰率增加1.63%、水分散失率增加0.38%,处于可以接受范围内,因此可以选为紫外照射稳定留胚米的工艺参数。     

微波消解法测定小麦胚芽中磷的含量

用微波消解技术对小麦胚芽进行前处理,然后用磷钼蓝分光光度法测定了其磷含量。使用微波消解炉,实验结果表明:该法操作简单、试剂用量少、重现性好,用微波消解技术大大缩短了样品前处理的时间,适于食品中磷元素含量的测定。     

Evaluation of the antioxidant and antiproliferative activities of extracted saponins and flavonols from germinated black beans (Phaseolus vulgaris L.)

Flavonoids and saponins from common beans have been widely studied due to their bioactivity. This research evaluated the effect of germination of black beans (Phaseolus vulgaris L.) on the antioxidant capacity and antiproliferative activity against cancer cell lines of saponins and flavonoids extracted from seed coats, cotyledons and sprouts. Principal component analysis was performed to achieve punctual associations between the black bean saponins and flavonoids concentrations to the antioxidant capacity and the antiproliferative activities. Total phenolic content and antioxidant capacity of extracts were higher when obtained from seed coats, mainly from the 3rd germination day. The extracts obtained from seed coats after 3 and 5 germination days inhibited all cancer cell lines proliferation with no cytotoxicity against control cells. Genistein was related with the activity against mammary cancer cells but flavonols and group B saponins were more related with hepatic and colon cancers. Non-glycosilated flavonols were related with antioxidant capacity.     

葡萄籽原花青素对顺铂诱导人胚肾细胞凋亡的拮抗作用

目的： 探讨葡萄籽原花青素（ g r a p e s e e d p r o a n t h o c y a n i d i n , G S P E ） 对顺铂（cis-diamminedichloroplatinum,CDDP）诱导人胚肾细胞HEK293凋亡及相关凋亡基因的影响,并探讨可能的机制。方法：体外培养正常HEK293细胞,噻唑蓝法测定GSPE、CDDP分别对HEK293细胞生长的影响以及GSPE对CDDP诱导HEK293细胞毒性的保护作用,流式细胞仪测定GSPE对CDDP所致HEK293细胞凋亡率的变化,Western blotting测定GSPE对CDDP所致HEK293细胞凋亡相关基因Bax、Bcl-2蛋白表达的影响。结果：GSPE对CDDP所致HEK293细胞毒性具有拮抗作用,可减轻CDDP所致HEK293细胞凋亡,减弱Bax表达、增强Bcl-2表达。结论：GSPE对CDDP所致HEK293细胞凋亡具有拮抗作用,其机制可能与GSPE降低促凋亡基因Bax,升高抗凋亡基因Bcl-2的表达有关。     

大豆胚芽油的提取及组成分析

以大豆胚芽出油率为指标,石油醚为脱脂溶剂,通过单因素和正交试验对大豆胚芽索氏提取工艺进行了研究,并用气相色谱对胚芽油的脂肪酸组成进行了分析。结果表明,大豆胚芽制油的最佳提取工艺为:粒度30目、料液比1:12、回流时间5h,在此条件下,大豆胚芽出油率为10.50%,其主要组成为亚麻酸20.73%、亚油酸52.21%、油酸10.51%、棕榈酸为13.47%。     

Extranuclear Inheritance of Mitochondrial Genome and Epigenetic Reprogrammability of Chromosomal Telomeres in Somatic Cell Cloning of Mammals

The effectiveness of somatic cell nuclear transfer (SCNT) in mammals seems to be still characterized by the disappointingly low rates of cloned embryos, fetuses, and progeny generated. These rates are measured in relation to the numbers of nuclear-transferred oocytes and can vary depending on the technique applied to the reconstruction of enucleated oocytes. The SCNT efficiency is also largely affected by the capability of donor nuclei to be epigenetically reprogrammed in a cytoplasm of reconstructed oocytes. The epigenetic reprogrammability of donor nuclei in SCNT-derived embryos appears to be biased, to a great extent, by the extranuclear (cytoplasmic) inheritance of mitochondrial DNA (mtDNA) fractions originating from donor cells. A high frequency of mtDNA heteroplasmy occurrence can lead to disturbances in the intergenomic crosstalk between mitochondrial and nuclear compartments during the early embryogenesis of SCNT-derived embryos. These disturbances can give rise to incorrect and incomplete epigenetic reprogramming of donor nuclei in mammalian cloned embryos. The dwindling reprogrammability of donor nuclei in the blastomeres of SCNT-derived embryos can also be impacted by impaired epigenetic rearrangements within terminal ends of donor cell-descended chromosomes (i.e., telomeres). Therefore, dysfunctions in epigenetic reprogramming of donor nuclei can contribute to the enhanced attrition of telomeres. This accelerates the processes of epigenomic aging and replicative senescence in the cells forming various tissues and organs of cloned fetuses and progeny. For all the above-mentioned reasons, the current paper aims to overview the state of the art in not only molecular mechanisms underlying intergenomic communication between nuclear and mtDNA molecules in cloned embryos but also intrinsic determinants affecting unfaithful epigenetic reprogrammability of telomeres. The latter is related to their abrasion within somatic cell-inherited chromosomes.     

Current Advancements in Noninvasive Profiling of the Embryo Culture Media Secretome

There have been over 8 million babies born through in vitro fertilization (IVF) and this number continues to grow. There is a global trend to perform elective single embryo transfers, avoiding risks associated with multiple pregnancies. It is therefore important to understand where current research of noninvasive testing for embryos stands, and what are the most promising techniques currently used. Furthermore, it is important to identify the potential to translate research and development into clinically applicable methods that ultimately improve live birth and reduce time to pregnancy. The current focus in the field of human reproductive medicine is to develop a more rapid, quantitative, and noninvasive test. Some of the most promising fields of research for noninvasive assays comprise cell-free DNA analysis, microscopy techniques coupled with artificial intelligence (AI) and omics analysis of the spent blastocyst media. High-throughput proteomics and metabolomics technologies are valuable tools for noninvasive embryo analysis. The biggest advantages of such technology are that it can differentiate between the embryos that appear morphologically identical and has the potential to identify the ploidy status noninvasively prior to transfer in a fresh cycle or before vitrification for a later frozen embryo transfer.     

Sire contribution to fertilization failure and early embryo survival in cattle

Despite passing routine laboratory tests of semen quality, bulls used in artificial insemination (AI) exhibit a significant range in field fertility. The objective of this study was to determine whether subfertility in AI bulls is due to issues of sperm transport to the site of fertilization, fertilization failure, or failure of early embryo or conceptus development. In experiment 1, Holstein-Friesian bulls (3 high fertility, HF, and 3 low fertility, LF) were selected from the national population of AI bulls based on adjusted fertility scores from a minimum of 500 inseminations (HF: +4.37% and LF: ?12.7%; mean = 0%). Superovulated beef heifers were blocked based on estimated number of follicles at the time of AI and inseminated with semen from HF or LF bulls (n = 3–4 heifers per bull; total 19 heifers). Following slaughter 7 d later, the number of corpora lutea was counted and the uteri were flushed. Recovered structures (oocytes/embryos) were classified according to developmental stage and stained with 4′,6-diamidino-2-phenylindole to assess number of cells and accessory sperm. Overall recovery rate (total structures recovered/total corpora lutea) was 52.6% and was not different between groups. Mean (± standard error of the mean) number of embryos recovered per recipient was 8.7 ± 5.2 and 9.4 ± 5.5 for HF and LF, respectively. Overall fertilization rate of recovered structures was not different between groups. However, more embryos were at advanced stages of development (all blastocyst stages combined), reflected in a greater mean embryo cell number on d 7 for HF versus LF bulls. Number of accessory sperm was greater for embryos derived from HF than for LF bulls. The aim of experiment 2 was to evaluate the effect of sire fertility on survival of bovine embryos to d 15. Day 7 blastocysts were produced in vitro using semen from the same HF (n = 3) and LF (n = 3) bulls and transferred in groups of 5–10 to synchronized heifers (n = 7 heifers per bull; total 42 heifers). Conceptus recovery rate on d 15 was higher in HF (59.4%,) versus LF (45.0%). Mean length of recovered conceptuses for HF bulls was not affected by fertility status. In conclusion, while differences in field fertility among AI sires used in this study were not reflected in fertilization rate, differences in embryo quality were apparent as early as d 7. These differences likely contributed to the higher proportion of conceptuses surviving to d 15 in HF bulls.     

基于斑马鱼胚胎急性毒性测试预测食用油毒性可行性研究

探讨利用斑马鱼胚胎预测食用油毒性的可行性。用乙腈和正己烷联合提取采自我国台湾地区的7个不同品质的猪油样本，并用甲醇溶解，然后用斑马鱼胚胎测试提取物的毒性，最后用非靶标高分辨率复合四极杆质谱仪偶联超高液相色谱/质谱系统进一步分析低毒、中毒、高毒代表性样本中的化学组成，结合ChemSpider、CT-link和Vega软件分析预测有毒物质的结构和功能。结果表明，不同品质的猪油样本毒性差异大，高毒性猪油的特征性质荷比信号相对应的化学成分为脂肪酸的氧化物，是样本的潜在有毒成分。斑马鱼胚胎急性毒性测试可准确地预测猪油品质，该方法为评估食用油安全提供了一个新的思路。     

Symposium review: Predicting pregnancy loss in dairy cattle

Several tools exist to diagnose pregnancy in dairy cattle. However, substantial pregnancy loss occurs within the first 60 d of gestation in cattle, and these losses have a profound adverse economic impact on the dairy and beef cattle industries. Detecting these impending pregnancy losses could offer producers an opportunity to reduce costs associated with this source of reproductive inefficiency. Several of the pregnancy diagnostic tools currently available and new technologies are being examined for their ability to predict pregnancies at risk for failing in early pregnancy. This review provides a synopsis of work undertaken recently to predict pregnancy losses in cattle. Currently, opportunities to predict pregnancy loss include (1) using transrectal ultrasonography to detect loss of the fetal heartbeat, floating debris within the placental fluids, and reductions in fetal size; (2) observing reductions in circulating progesterone concentrations; (3) detecting reductions in concentrations of circulating placental products; namely, pregnancy-associated glycoproteins and microRNAs; and (4) detecting reductions in the early pregnancy-dependent increase in interferon-stimulatory gene expression in peripheral blood leukocytes. An achievable goal may be to identify markers of embryo mortality so that researchers and clinicians can focus their efforts on developing intervention strategies for cows identified to be at risk for pregnancy failure.