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81.
Royal jelly from Apis mellifera is a highly active natural biological substance and is probably one of the most interesting raw substances in natural product chemistry. Trace elements play a key role in the biomedical activities associated with royal jelly, as these elements have a multitude of known and unknown biological functions. For this reason concentrations of 28 trace (Al, Ba, Sr, Bi, Cd, Hg, Pb, Sn, Te, Tl, W, Sb, Cr, Ni, Ti, V, Co, Mo) and mineral (P, S, Ca, Mg, K, Na, Zn, Fe, Cu, Mn) elements were systematically investigated in botanically and geologically defined royal jelly samples. In addition, concentrations of 14 trace elements were measured in the associated honey samples--honey being the precursor of royal jelly. Concentrations of K, Na, Mg, Ca, P, S, Cu, Fe, Zn, Al, Ba and Sr in royal jelly were determined by inductively coupled plasma optical emission spectroscopy (ICP-OES), while concentrations of Bi, Cd, Hg, Pb, Sn, Te, Tl, W, Sb, Cr, Mn, Ni, Ti, V, Co and Mo in royal jelly were determined by double focusing magnetic sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). In the honey samples, trace and mineral element concentrations strongly depended on botanical and geological origin, and substantial variation was found. In contrast, the concentrations of trace and mineral elements were highly constant in the associated royal jelly samples. The most important results were the homeostatic adjustments of trace and mineral element concentrations in royal jelly. This effect was evidently produced in the endocrine glands of nurse bees, which are adapted for needs of bee larvae. In conclusion, this research yielded a surprising and completely new finding--that royal jelly, as a form of lactation on the insect level, shows the same homeostatic adjustment as mammalian and human breast milk.  相似文献   
82.
陈盛禄  李建科  钟伯雄  苏松坤 《遗传学报》2005,32(10):1037-1044
我国培育成功的世界上蜂王浆产量最高的蜂种(Ea)是从20世纪30年代引进我国的意大利蜜蜂(Eb)中选育的。采用10个微卫星位点对蜂王浆高产蜜蜂、原种意大利蜜蜂(Ee)和本地意大利蜜蜂进行研究,以探明由于人工选择和地理隔离造成的其分子进化上的一些特征。结果,10个微卫星位点在3个蜂种中共扩增到96个等位基因,其中有48个等位基因是不同的,表明10个微卫星位点在3个蜂种中的高度多态性,而且由于人工选择和地理隔离已造成3蜂种在遗传基础上的一些分化。3蜂种的多态信息含量(PIC)分别为0.57、0.50、0.57,杂合度分别为0.60、0.57、0.61,二者均无显著差异。遗传距离的分析结果显示,Ee和Eb(0.14)、Eb和Ea(0.16)之间的遗传距离较近,而Ea和Ee(0.25)之间的遗传距离较远。等位基因频率的分析结果表明,6个位点的7个等位基因的频率(A29的159bp、A24的100bp和104bp、A7的110bp、A43的126bp、A14的221bp和A113的221bp)以Ee、Eb、Ea的顺序递增,Ea的这7个等位基因频率分别显著高于Ee和Eb。同时4个位点的4个等位基因的频率(A24的106bp、A43的140bp;A113的215bp和A14的219bp)以Ea、Eb、Ee的Ⅲ页序下降,Ea在这4个位点的频率分别显著低于Eb和Ee。这些位点的等位基因可能与蜂王浆产量有关。  相似文献   
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This study was conducted to examine the effect of supplementation of Tris-egg yolk extender with lyophilized royal jelly (RJ) on chilled and frozen-thawed ram semen parameters. Ejaculates were collected by artificial vagina from 4 mature rams, twice a week for 4 weeks. Only samples with motility of ≥70% were included, pooled and divided into four equal parts and then diluted in extenders with various concentrations of RJ (0, 1, 3 and 5%, vol/vol) to a final concentration of 200 × 106 sperm/mL and was incubated at 37 °C for 30 min and were subsequently evaluated. After equilibration of extended semen for 2 h at 4 °C, some semen samples were packed in 0.25 mL plastic straws. Then, the straws were frozen in the liquid nitrogen vapor phase for 15 min and stored at −196 °C in liquid nitrogen. The frozen straws were thawed in warm water (37 °C) for 30 s and evaluated; whereas, other semen samples were stored in the refrigerator (4 °C) up to 7 days. The chilled samples were kept in water bath (37 °C) for 5 min and then were evaluated. After dilution, the lowest and highest sperm total abnormality was recorded in 3 and 5% RJ supplemented groups, respectively (P < 0.05). The chilled sperm total motility and membrane integrity were significantly (P < 0.05) higher in 3% than those in 0% and 5% RJ supplemented groups. The chilled sperm progressive motility and viability was significantly (P < 0.05) higher in 1 and 3% than those in 0 and 5% RJ supplemented groups. The frozen-thawed sperm total motility, progressive motility, membrane integrity and viability were significantly higher in 3% RJ supplemented group (P < 0.05). In conclusion, supplementation of Tris-egg yolk extender with 3% lyophilized RJ had a protective effect on chilled and cryopreserved ram spermatozoa.  相似文献   
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BackgroundHuman Wharton's jelly–derived mesenchymal stromal cells (hWJSCs) have gained considerable attention for their use in cell therapy. Many of these applications would require manufacturing of millions of hWJSCs. It is, therefore, necessary to develop a Good Manufacturing Practice (GMP)-compliant hWJSC expansion protocol, allowing the generation of a large quantity of cells to meet both clinical and regulatory requirements. Here, we compared human platelet lysate (HPL) and human serum (HS) in supporting clinical-grade hWJSC expansion.MethodshWJSCs were successfully isolated from six different umbilical cords using GMP-compliant dissociation enzymes. Freshly isolated hWJSCs were cultured in media supplemented with 10% of one of the following sera: fetal bovine serum (FBS), HPL and HS. Properties of the expanded hWJSCs were analyzed.ResultsWe showed that GMP-compliant dissociation enzymes were as efficient as research-grade dissociation enzymes in isolating hWJSCs. hWJSC fresh cell yield and cell viability using HPL and HS supplementations were at greater advantages than FBS. Moreover, hWJSCs expanded in HPL and HS supplementations not only preserved classical MSCs phenotypes and differentiation potential to adipocytes, osteocytes and chondrocytes, they also enhanced the migration of skin fibroblasts. However, HS, unlike HPL, did not alter immunogenicity properties of hWJSCs. hWJSCs expanded in HS supplementation also exerted greater immunosuppressive action in inhibiting T-cell proliferation and increased extracellular matrix (ECM) gene expression, making them useful in tissue repair clinical application.ConclusionOur findings indicate that HS can be considered as a promising and safer alternative to FBS, and should be recommended for clinical-grade expansion of hWJSCs.  相似文献   
88.
Stem cells are being evaluated in numerous human clinical trials and are commercially used in veterinary medicine to treat horses and dogs. Stem cell differentiation, homing to disease sites, growth and cytokine factor modulation, and low antigenicity contribute to their therapeutic success. Bone marrow and adipose tissue are the two most common sources of adult-derived stem cells in animals. We report on the existence of an alternative source of primitive, multipotent stem cells from the equine umbilical cord cellular matrix (Wharton's jelly). Equine umbilical cord matrix (EUCM) cells can be cultured, cryogenically preserved, and differentiated into osteo-, adipo-, chondrogenic, and neuronal cell lineages. These results identify a source of stem cells that can be non-invasively collected at birth and stored for future use in that horse or used as donor cells for treating unrelated horses.  相似文献   
89.
The eggs of Xenopus laevis are surrounded by investment layers of egg jelly that interact with the sperm immediately prior to fertilization. Components of these egg jelly layers are necessary for the fertilization of the egg by incoming sperm. Eggs which are stripped of their jelly layers are refractile to fertilization by sperm, but the addition of solubilized jelly promotes fertilization. We have shown previously that the egg jelly layers are composed of a fibrous network of glycoconjugates which loosely hold smaller diffusible components. Extracts of these diffusible components were prepared by incubation of freshly ovulated eggs in high-salt buffers for 12 h at 4°C. This diffusible component extract, when incubated with sperm, promoted the sperm's ability to fertilize dejellied eggs in a dose-dependent manner. In contrast, the high-molecular-weight “structural” glycoconjugates of jelly that remain after extraction of the diffusible components did not increase fertilization efficiency of dejellied eggs nor did nonspecific proteins, carbohydrate polymers, or organic polymers. The diffusible components, analyzed by SDS–PAGE, consisted of a mixture of proteins from 4 to 180 kDa. The protein responsible for fertilization rescue appeared to be <50 kDa and appeared to self-aggregate or to bind to larger proteins. This protein component was required during sperm binding to the egg, its action required an intact egg vitelline envelope, and its action was independent of large soluble polymers such as Ficoll.  相似文献   
90.
孟飞  胥保华  郭兴启 《昆虫知识》2012,49(5):1338-1344
中华蜜蜂Apis cerana cerana Fabricisus是一种重要的经济动物,具有嗅觉敏锐,抗寒耐热,抗螨及采集能力强等特点.目前人们采用分子生物学的方法,对中华蜜蜂的基因组成、基因表达调控及基因功能分析等方面开展研究,揭示其特征行为的分子机理已成为该领域的研究热点之一.近年来,中华蜜蜂重要生物学特征功能相关基因(即蜂王浆蛋白相关基因、化学通讯相关蛋白基因和抗逆相关基因)在基因克隆、表达特性及功能研究等方面取得了重大进展.本文重点对此进行综述.  相似文献   
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