雏鸡公母鉴别方法18种

据《陕西农业》,这里简介鉴别雏鸡公母的8个方面18种方法,供参考。 1蛋形鉴别 蛋形较尖的蛋,孵出来的是公雏;较圆的孵出来的是母雏。

Gfi1.1 regulates hematopoietic lineage differentiation during zebrafish embryogenesis

Growth factor independence 1 （GFI1） is important for maturation of mammalian lymphocytes and neutrophils and maintenance of adult hematopoietic stem cells （HSCs）. The role of GFI1 in embryonic hematopoiesis is less well characterized. Through an enhancer trap screen and bioinformatics analysis, we identified a zebrafish homolog of Gill （named grill） and analyzed its function during embryonic development. Expression of both an endogenous griLl gene and a GFP reporter gene inserted near its genomic locus was detected in hematopoietic cells of zebrafish embryos. Morpholino （MO） knockdown of gill.1 reduced expression of scl, Imo2, c-myb, mpo, ragl, gatal and hemoglobin alpha embryonic-1 （hbael）, as well as the total amount of embryonic hemoglobin, but increased expression ofpu.1 and l-plastin. Under the same conditions, MO injection did not affect the markers involved in vascular and pronephric development. Conversely, overexpression of gill.1 via mRNA injection enhanced expression ofgatal but inhibited expression ofpu.1. These findings suggest that Gill.1 plays a critical role in regulating the balance of embryonic erythroid and myeloid lineage determination, and is also required for the differentiation of lymphocytes and granulocytes during zebrafish embryogenesis.

Agrobacterium-mediated transformation of herbicide resistance in creeping bentgrass and colonial bentgrass

Embryogenic calli were induced from the seeds of creeping bentgrass ( Agrostis palustris Huds.) cv. Regent and colonial bentgrass ( Agrostis Tenuis Sibth. Fl. Oxen.) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4-7 days and then co cultivated with Agrobacterium tumefaciens , LBA4404, which contains plasmid vector pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding region and matrix attachment region (MAR). After 3 days of co cultivation, the calli were washed thoroughly and transferred to MS medium containing 2 mg/L of 2, 4 D, 12-15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2-3 months of selection, the actively growing calli of 'Regent' and 'Tiger' were transferred to MS medium with 12-15 mg/L PPT and 250 mg/L cefotaxime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4% of herbicide Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants and its absence in a randomly selected control plant.

Establishment of a transplantation tumor model of human osteosarcoma in chick embryo

Objective: We established a transplantation tumor model of human osteosarcoma in chick embryo, studied its morphological and biological characteristics, and observed its dynamic process of angiogenesis induction so that a simple and practical model can be provided for studying osteosarcoma. Methods: Human osteosarcoma cells at different concentrations were inoculated in chorioallantoic membrane (CAM) of chick embryos at different embryonic ages to observe the factors affecting the survival of the transplanted osteosarcoma in chick embryo, growth characteristics of the transplantation tumor, and the morphological characteristics and biological characteristics of the transplantation tumor. Results: The transplantation tumor model of human osteosarcoma in chick embryo was successfully established. It was found that the transplantation tumor was easy to grow and it showed strong angiogenesis-inducing effects. Under the light microscope, the transplantation tumor showed a similar tissue structure to human osteosarcoma. Conclusion: It is feasible to establish a transplantation tumor model of human osteosarcoma in chick embryo. The model can be easily duplicated with a simple operation, which provides a useful animal model for studying osteosarcoma.

Double Pulmonary Embolism and Left Common Iliac Vein Thrombosis after in vitro fertilization and embryo transfer： a Case Report

This article discusses the mechanism, diagnosis, and treatment of a case of double pulmonary embolism and left common iliac vein thrombosis following in vitro fertilization （IVF） and embryo transfer （ET） to arouse vigilance for unexpected thrombosis after ovarian hyperstimulation and to serve as a clinical reference of this condition. This paper reports the case of a woman with double pulmonary embolism and left common iliac vein thrombosis after IVF-ET and the successful management of this condition. The woman had primary infertility, and underwent IVF-ET with 14 ooeytes recovered and two embryos transferred. The patient suffered breathing difficulty 17 days after the ET, and was hospitalized 6 days later as her condition had exacerbated. Computed tomographic （CT） angiography of pulmonary arteries showed double pulmonary embolism, left common iliae vein thrombosis, abnormal density shadow in uterine appendages, and ascites. A healthy baby boy and girl were safely delivered by Caesarean section after successful treatment. Thrombosis after IVF-ET is an uncommon but life-threatening complication and concurrent pulmonary embolism is even rarer. It is suggested that careful thrombosis risk assessment be taken before therapy and particular attention be paid to patients with special body constitutions to develop thrombosis. Whenever patients experience breathing difficulty after IVF-ET, it is strongly advised to examine the possibility of pulmonary embolism. The main treatments for thrombosis are anticoagulant therapy by low-molecular-weight heparin and thrombolysis by urokinase.

GPCR-CARMA3-NF-kappaB Signaling Axis： A Novel Drug Target for Cancer Therapy

G protein-coupled receptors （GPCRs） play pivotal roles in regulating various cellular functions. It has been well established that GPCR activates NF-κB and aberrant regulation of GPCR-NF-κB signaling axis leads to cancers. However, how GPCRs induce NF-κB activation remains largely elusive. Recently, it has been shown that a novel scaffold protein, CARMA3, is indispensable in GPCR-induced NF-κB activation. In CARMA3-deficient mouse embryonic fibroblast cells, some GPCR ligand-, like lysophosphatidic acid （LPA）, induced NF-κB activation is completely abolished. Mechanistically, upon GPCR activation, CARMA3 is linked to the membrane by β-arrestin 2 and phosphorylated by some PKC isoform. Phosphorylation of CARMA3 unfolds its steric structure and recruits its downstream effectors, which in turn activate the IKK complex and NF-κB. Interestingly, GPCR （LPA）-CARMA3-NF-κB signaling axis also exists in ovarian cancer cells, and knockdown of CARMA3 results in attenuation of ovarian cancer migration and invasion, suggesting a novel target for cancer therapy. In this review, we summarize the biology of CARMA3, discuss the GPCR （LPA）-CARMA3-NF-κB signaling axis in ovarian cancer and speculate its potential role in other types of cancers. With a strongly increasing tendency to identify more LPA-like ligands, such as endothelin-1 and angiotensin II, which also activate NF-κB through CARMA3 and contribute to myriad diseases, GPCR-CARMA3-NF-κB signaling axis is emerging as a novel drug target for various types of cancer and other myriad diseases.

ISOBUTYRAMIDE ACTIVATES TRANSCRIPTION OF HUMAN FETAL γ-AND MURINE EMBRYONIC εy-GLOBIN GENES

Objective. To examine the effect of isobutyramide synthesized in our laboratory on human and murine globin gene expression and to test cell toxicity ofthe drug.Methods. MEL cells were transfected with the recombinant construct μLCRAγψβδβand the stable transformants were cultured in the medium with different concentrations of isobutyramide. The experimental mice and rabbit were injected with different doses of isobutyramide. The globin mRNAs were analyzed by RNase protection assay. The hematological toxicity and electrolyte toxicity ofthe drug were tested.Results. An inducible and dose dependent expression of the human γ , β and mouse α globin gene was observed in the transfected MEL cells. The induction of the human γ globin gene is significant stronger than that of the β globin gene. With 2.5～5 mmol/L isobutyramide, the induction of the human γ globin gene is even more effective than that of mouse α globin gene. After a 15 day injection under the doses of 500～900mg·kg-1·d-1, the level of the mouse embryonic εy globin mRNA could be significantly induced up to 3～4 fold of that of uninjected controls. The changes of hemoglobin(Hb), RBC, hematocrit(HCT), WBC, derived from mice injected with different doses of isobutyramide at the interval of 24 hours for 2～4 weeks, were generally within the normal range. In rabbits injected with isobutyramide in the same regiment for 2 weeks, the concentration of blood K+, Na+, Cl-and CO2 were all within normal range and serum ionic osmotic pressure remained stable as well. Conclusion. Our results suggested that isobutyramide is a weak inducer ofcell differentiation, but it can selectively activate transcription of human γ globin gene at a certain degree, and it can act on early stages of erythroid progenitor differentiation in adult mice and activate transcription of embryonic εy-globin gene and have no hematological toxicity. Our results have further proved the potential value of isobutyramide in treatment of β-thalassemia and sickle cell disease.

VEGFR-3 ligand-binding and kinase activity are required for lymphangiogenesis but not for angiogenesis

Although VEGFR-3 deficiency disrupts blood vascular development during early embryogenesis, the underlying mechanism was not clear. To characterize its function in angiogenesis and lymphangiogenesis, we employed two genetically modified mouse models in this study, targeting the coding region for the ligand-binding domain （Vegfr△LBD） or the tyrosine kinase domain with an inactivation point mutation （Vegfr3^TKmat）. We show that lymphatic growth was disrupted in Vegfr3△LBD/△LBD and Vegfr3^TKmut3^TKmat mice, but blood vessels developed normally in both embryo and yolk sac. Interestingly, in Vegfr3△LBD/△LBD but not Vegfr3^TKmut3^TKmat mice, lymph sac was present but there was lack of iym- phangiogenic sprouting. We further demonstrate that both the wild-type and mutant forms of VEGFR-3 could form heterodimers with VEGFR-2, and decreased the level of phospho-VEGFR-2 and the downstream phospho-Erk1/2 in endothelial cells when they were treated with VEGF-A. These findings indicate that signaling mediated via VEGFR-3 activation by its cognate ligands （VEGF-C/-D） is not required for angiogenesis, and that VEGFR-3 may play a role in this process by modulating VEGFR-2-mediated signals.

血-视网膜外屏障发育的研究现状

血-视网膜外屏障（BRB）由视网膜色素上皮（RPE）细胞间的连续网状紧密连接构成，是维持视网膜及视觉生理状态的重要基础。BRB由视神经管的膨出部分视泡发育而来，随着胚胎发育逐渐形成。发育过程中紧密连接复合体的结构及分子组成均发生了改变，且受周围组织的调控。BRB的发育具有种属差异。干细胞来源的RPE细胞有可能成为研究RPE屏障功能的最佳模型。

21世纪生物抗衰老极品

北京邦定美容保健机构依靠军事医学科学院雄厚的生物医学力量,将国外先进的抗衰老技术与中国的美容实践相结合,在94年首先推出“邦定系列生物精华素”之后,又成功地为国人创制了一套完整的抗衰老美容技术——“胚胎血清不老术” 胚胎血清不老术的作用原理和组成 胚胎血清不老术源于科学家对皮肤生理功能和皮肤营养供应方式的深入研究。正常皮肤细胞的生长分化等新陈代谢有赖于皮肤毛细血管中的血清组织液的滋养,因而国际上一流的生物科学家们公认生物血清类护肤品将成为人体皮肤最好的营养剂。外用养护血清加上人体皮下血管溢出的血清。

From stem cells to red blood cells:how far away from the clinical application?

The generation of red blood cells(RBCs)from stem cells provides a solution for deficiencies in blood transfusion.Currently,primary hematopoietic stem cells,embryonic stem cells and induced pluripotent stem cells have shown the potential to produce fully mature RBCs.Here,we discuss the advantages,induction protocols,progress and possible clinical applications of stem cells in RBC production.

Inducible overexpression of RUNX1b/c in human embryonic stem cells blocks early hematopoiesis from mesoderm

RUNXI is absolutely required for definitive hematopoiesis, but the function of RUNXlb/c, two isoforms of human RUNX1, is unclear. We established inducible RUNXlb/c-overexpressing human embryonic stem cell （hESC） lines, in which RUNXlb/c overexpression prevented the emergence of CD34＋ cells from early stage, thereby drastically reducing the production of hematopoi- etic stem/prognnitor cells. Simultaneously, the expression of hematopoiesis-related factors was downregulated. However, such blockage effect disappeared from day 6 in hESC/AGM-S3 ceU co-cultures, proving that the blockage occurred before the generation of hemogenic endothelial cells. This blockage was partially rescued by RepSox, an inhibitor of the transforming growth factor （TGF）-β signaling pathway, indicating a close relationship between RUNX1b/c and TGF-β pathway. Our results suggest a unique inhibitory function of RUNX1b/c in the development of early hematopoiesis and may aid further understanding of its biological function in normal and diseased models.

Curative effect of assisted reproduction technology by Traditional Chinese Medicine multi-channel interventional therapy on 95 cases of in vitro fertilization and embryo transfer failure

OBJECTIVE: To evaluate the curative effect of Traditional Chinese Medicine(TCM) multi-channel interventional therapy on women with Assisted Reproductive Technology(ART) failure, to compare the curative effect of the dual therapy and triple therapy on women with ART Failure, and to choose the best TCM interventional therapeutic plan.METHODS: The 95 cases with ART Failure from West China second University Hospital of Sichuan University meeting the inclusion criteria were randomly divided into three groups:dual therapy group(31 cases), triple therapy group(33 cases)and control group(31 cases). According to the intervene treatment of in vitro Fertilization and Embryo Transfer(IVF-ET) long cycle scheme, the control group wait naturally for 3 months before IVFET. The dual therapy group take TCM prescriptionⅡ of cultivating emotion and assisting reproduction and auricular acupoint therapy for 3 months before IVF-ET, then Western Medicine treatment progestin supporting as well as auricular application and Antai Recipe after IVF-ET transplantation.The triple therapy group take TCM prescription Ⅱof cultivated emotion and assisted reproduction,auricular acupoint therapy and retention enema of TCM, and combination treatment the same as dual therapy group after transplantation. The natural pregnancy number, the period condition of secondary IVF-ET and the improvement of the kidney deficiency, liver depression and blood stasis syndrome among those three groups were compared.RESULTS: It was showed from analysis in 95 cases with ART failure that the number of natural preg-nancy was as followings: 3 patients from the dual therapy group, 10 patients from the triple therapy group, and no patient from the control group. The comparison among three groups have statistical significance(P < 0.05). The treatment group is superior to the control group, while the triple therapy is superior to the dual therapy. The comparison of the condition of the fertility rate, clinical pregnancy rate, biochemical pregnancy rate and early abortion rate during the period of secondary IVF-ET between pre-therapy and post-treatment of both the dual therapy group and the triple therapy group have statistical significance(P < 0.05). The comparison of the improvement of the kidney deficiency,liver depression and blood stasis syndrome between pre-therapy and post-treatment of both the dual therapy group and the triple therapy group have statistical significance(P < 0.05). The comparison between three groups after treatment have statistical significance(P < 0.05).CONCLUSION: TCM multi-channel interventional therapy can increase the natural pregnancy rate of patients with ART Failure(the triple therapy is superior to the dual therapy); it can increase the fertility rate, clinical pregnancy rate, and decrease the early abortion rate during the period of secondary IVF-ET; it can improve syndromes of kidney deficiency, liver depression and blood stasis.

Interplay of transcription factors and microRNAs during embryonic hematopoiesis

Hematopoietic stem cells (HSCs), which are localized in the bone marrow of adult mammals, come from hematopoietic endothelium during embryonic stages. Although the basic processes of HSC generation and differentiation have been described in the past, the epigenetic regulation of embryonic hematopoiesis remains to be fully described. Here, by utilizing an in vitro differentiation system of mouse embryonic stem cells (ESCs), we identified more than 20 microRNAs that were highly enriched in embryonic hematopoietic cells, including some (e.g. miR-10b, miR-15b, and miR-27a) with previously unknown functions in blood formation. Luciferase and gene expression assays further revealed combinational binding and regulation of these microRNAs by key transcription factors in blood cells. Finally, bioinformatics and functional analyses supported an interactive regulatory control between transcription factors and microRNAs in hematopoiesis.