Aim:To examine the transfection of exogenous genes into chick embryos,applying the characteristics of avianleukosis vires(ALV)-induced chicken B cell line DT40 to the production of chimeric birds.Methods:The DT40cells...Aim:To examine the transfection of exogenous genes into chick embryos,applying the characteristics of avianleukosis vires(ALV)-induced chicken B cell line DT40 to the production of chimeric birds.Methods:The DT40cells incorporated with exogenous gene(lacZ constructs encoding Escherichia coliβ-galactosidase:β-gal)were intro-duced into chick embryos by the injection of cells into stage X blastoderm.Manipulated eggs were incubated for 3(trial1)or 6(trial 2)days,and the expression of lacZ DNA was detected by a histochemical staining method ofβ-galactosi-dase and polymerase chain reaction(PCR)analysis.Results:The survival rates of the manipulated embryos incu-bated for 3 days(stage 18-20:trial 1)and 6 days(stage 28,30:trial 2)were about 42%and 38%,respectively.The expression rates of the lacZ gene in the embryos in the trials 1 and 2 were about 60%and 23%,respectively,forthe survived embryos.Conclusion:The rate of embryonic viability and expression rate of introduced genes were notso high,but it suggested the possibility of utilizing the DT40 cells as a vector for carrying exogenous genes into chickembryos.展开更多
The effects of thyroxine and atropine in ameliorating phosphamidon intoxication in chick embryos was studied. Treatment of phosphamidon significantly enhanced the moriality and abnormalityrates, decreased the average ...The effects of thyroxine and atropine in ameliorating phosphamidon intoxication in chick embryos was studied. Treatment of phosphamidon significantly enhanced the moriality and abnormalityrates, decreased the average body weights, and cholinesterase activity in chick embryos. When thyroxine was administered to the phosphamidon intoxicated embryos, the above parameters changedsignificantly, indicating an ameliorating effect of thyroxine against phosphamidon intoxication in chick embryos. The combined thyroxine and atropine therapy did not further improve the ameliorating effect. Since in many respects chick embryo development parallels that of mammalian embryos,a short-term use of thyroxine as a protective agent against organophosphate toxicity might be useful展开更多
Pesticides are reported to be teratogenic for non-target species.Our studies have unraveled the teratogenicity of 50%Chlorpyrifos&5%Cypermethrin combination(Ci)in developing chick embryos.A sublethal dose of this ...Pesticides are reported to be teratogenic for non-target species.Our studies have unraveled the teratogenicity of 50%Chlorpyrifos&5%Cypermethrin combination(Ci)in developing chick embryos.A sublethal dose of this combination when administered to chick embryos,caused several developmental anomalies,with defects in eye development being frequent.Eye development begins at an early embryonic stage,with Sonic hedgehog(Shh)serving as a crucial signaling molecule.Shh plays a pivotal role in the early development of multiple organs,including the eye,by interacting with Pax6 and other regulatory molecules to guide the proper patterning of the eye.Thus,we hypothesized that Ci administration may lead to alteration in Shh expression which subsequently hampers downstream signaling molecules potentially contributing to congenital eye defects.Morphological,anatomical,histological,transcriptional and protein level analyses at various stages(Days 1,2,4 and 10)were carried out to evaluate the hypothesis.The results revealed a remarkable alteration of key regulators in treated embryos compared to control,providing insights into plausible causative mechanisms underlying Ciinduced congenital eye defects.展开更多
Aim: This study was designed to investigate the effect of busulfan treatment on the proliferation of chicken primordialgerm cells (PGCs) in vivo, focusing on the preferential settlement of PGCs onto the germinal ridge...Aim: This study was designed to investigate the effect of busulfan treatment on the proliferation of chicken primordialgerm cells (PGCs) in vivo, focusing on the preferential settlement of PGCs onto the germinal ridges of chicken em-bryos. Methods: Busulfan (250 ng/egg) was injected into the egg white of freshly oviposited fertilized eggs, whichwere then incubated. Embryonic development and viability were examined, and exogenous PGCs collected from embry-onic blood vessels were injected into the germinal crescent region of recipient embryos. The number of PGCs residedonto germinal ridges of the right and left sides were compared. Results: Busulfan had a slight harmful effect on theembryo viability and the PGCs proliferation. The number of PGCs resided onto the left side of germinal ridges wasslightly higher as compared with the right side. Conclusion: Busulfan suppressed the viability of embryos and the pro-liferation of endogenous PGCs in the recipient embryos. However, the number of exogenous PGCs proliferated washigher in embryos treated with busulfan than those without busulfan. Data also suggest the possibility of a preferentialresidence of PGCs toward the left side of the germinal crescent region as compared with the fight, which may be due toa more advanced functional development of the left gonad than the right. (Asian J Androl 1999 Dec; 1: 187-190)展开更多
In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation. Transferring exogenous substances into chicken embryos for producing ...In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation. Transferring exogenous substances into chicken embryos for producing medical antibodies has been widely used in the production practice. However, there are few studies about the effect of the different injection site and dosage on chicken embryos. The aim of this study was to explore the effects of different injection sites and dosages on chicken embryo hatching rate and development, so as to provide a basis for further studies using the chicken embryo model. Freshly laid eggs （Rugao yellow chicken） were injected with different doses of saline at the tip, equatorial plane and the blunt end of the egg shell, respectively. Egg hatching rate was recorded and compared among injection sites and different doses. A trypan blue stain was also injected at the aforementioned sites and the growth of chicken embryos was observed. The SPSS （statistical package for the social science） software was used to analyze the relationship between the chicken eggs hatching rate and the different injection sites or the different dosages. The experimental results showed that there were significant differences on egg hatching rates among the different injection sites and doses （P〈0.05）. The hatchability of the blunt end injection group was significantly higher than that of the other two sites. The egg hatching rate decreased with increased saline doses. The egg hatching rate of the 100 pL saline injection group was higher than the 200 and 300 μL dosage groups. Ultimately, we suggest that the optimal chicken embryo injection process is during early development, at the blunt end site with a dose less than 100 μL to minimize damage to the egg.展开更多
In the present study, the effect of manganese（Mn） on antioxidant status and the expression of the manganese superoxide dismutase（MnSOD） gene in cultured primary myocardial cells collected from the chick embryos wa...In the present study, the effect of manganese（Mn） on antioxidant status and the expression of the manganese superoxide dismutase（MnSOD） gene in cultured primary myocardial cells collected from the chick embryos was investigated. The hypothesis that Mn supplementation would enhance the expression of MnSOD in cultured primary myocardial cells of chick embryos was tested. Eggs collected from Mn-depleted Arbor Acres laying breeder hens were incubated for 10 days and then myocardial cells were isolated and cultivated for 8 days. The embryonic myocardial cells on day 6 were treated with Mn in the cell culture medium at different time points when the proportion of cells showing spontaneous contraction was over 95% after the 3-day primary culture. A completely randomized design involving a 3 Mn levels（0, 0.5 and 1.0 mmol L^（-1））×3 incubation time points（12, 24 and 48 h） factorial arrangement of treatments（n=6） was used in the current experiment. The results showed that MnSOD activity and m RNA expression level were induced by Mn and increased with incubation time, which supported the hypothesis that Mn would enhance the expression of the MnSOD gene, and thus might protect myocardial cells from oxidative stress during the chick embryonic development.展开更多
Members of the basic helix-loop-helix （bHLH） gene family play important roles in vertebrate neurogenesis. In this study, confocal microscopy-based fluorescence resonance energy transfer （FRET） is used to monitor b...Members of the basic helix-loop-helix （bHLH） gene family play important roles in vertebrate neurogenesis. In this study, confocal microscopy-based fluorescence resonance energy transfer （FRET） is used to monitor bHLH protein-protein interactions under various physiological conditions. Tissue-specific bHLH activators, NeuroD 1, Mash 1, Neurogenin 1 （Ngn 1）, Neurogenin2 （Ngn2）, and ubiquitous expressed E47 protein are tagged with enhanced yellow fluorescence protein （EYFP） and enhanced cyan fluorescence protein （ECFP）, respectively. The subcellular localization and mobility ofbHLH fusion proteins are examined in HEK293 cells. By transient transfection and in ovo electroporation, four pairs of tissue-specific bHLH activators and E47 protein are over-expressed in HEK293 cells and developing chick embryo neural tube. With the acceptor photobleaching method, FRET could be detected between these bHLH protein pairs in the nuclei of transfected cells and developing neural tubes. Mashl/E47 and Ngn2/E47 FRET pairs show higher FRET efficiencies in the medial and the lateral half of chick embryo neural tube, respectively. It suggests that these bHLH protein pairs formed functional DNA-protein complexes with regulatory elements of their downstream target genes in the specific regions. This work will help one understand the behaviours of bHLH factors in vivo.展开更多
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 th...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.展开更多
Thyroid hormone deficiency was created artificially in chick embryos by injecting propyl-thiouracil (PTU).The tubulin was quantified by ~3H-colchicine assay(expressed as colchicine binding activity).Thyroid hormone de...Thyroid hormone deficiency was created artificially in chick embryos by injecting propyl-thiouracil (PTU).The tubulin was quantified by ~3H-colchicine assay(expressed as colchicine binding activity).Thyroid hormone deficiency resulted in 16％ to 28％ decline of the tubulin level in the developing chick brain from 15 to 19 days of embryonic age as compared with the control,whereas the total protein amount was not significantly affected.It suggests that thyroid hormone specifically affected the synthesis of brain tubulin.展开更多
[Objective] This study was to investigate the effect of forsythiaside A added in chick embryo kidney cells (CEKs), on the changes in expression of interferon α(IFN-α) and mRNA expression level of correlated factors ...[Objective] This study was to investigate the effect of forsythiaside A added in chick embryo kidney cells (CEKs), on the changes in expression of interferon α(IFN-α) and mRNA expression level of correlated factors in JAK-STAT pathway. [Methods] Three levels of forsythiaside (100, 200, 400 μg/ml) were adopted to treat the experimental materials, then the expression levels of IFN-α and correlated factors in JAK-STAT pathway were detected by real-time RT-PCR at the transcriptional level (mRNA) and by Western blot at the translation level(IFN-α protein). [Result] Compared with the control group (untreated group), Application of forsythiaside A not only significantly increased the expression of IFN-α in treated CEKs (P<0.05) , but also up-regulated the expression of STAT1, JAK1, IFNAR1, IFNAR2, IRF1 and IRF7, the correlated factors in JAK-STAT pathway. [Conclusion] Forsythiaside A induced the expression of IFN-α in CEKs, and can positively regulate the JAK-STAT signaling pathway significantly.展开更多
Carbon nanotubes can carry protein into cells to induce biological effects. Amino-functionalized carbon nanotubes are soluble and biocompatible, have high reactivity and low toxicity, and can help promote nerve cell g...Carbon nanotubes can carry protein into cells to induce biological effects. Amino-functionalized carbon nanotubes are soluble and biocompatible, have high reactivity and low toxicity, and can help promote nerve cell growth. In this study, amino-functionalized ethylenediamine-treated multi-walled carbon nanotubes were used to prepare carbon nanotubes-nerve growth factor complexes by non-covalent grafting. The physicochemical properties, cytotoxicity to PC12 and chick embryo dorsal root ganglion, and biological activity of the carbon nanotubes-nerve growth factor complexes were investigated. The results showed that amino functionalization improved carbon nanotubes-nerve growth factor complex dispersibility, reduced their toxicity to PC12 cells, and promoted PC 12 cell differentiation and chick embryo dorsal root ganglion.展开更多
In order to investigate the angiogenic effect of intercellular adhesion molecule-1 （ICAM-1）, two parts of experiment were performed. Chick embryo chorioallantoic membrane （CAM） assay was used for in vivo angiogeni...In order to investigate the angiogenic effect of intercellular adhesion molecule-1 （ICAM-1）, two parts of experiment were performed. Chick embryo chorioallantoic membrane （CAM） assay was used for in vivo angiogenic research. The chick embryos were divided into 4 groups： ICAM-1 group （divided into 3 subgroups, Ⅰ, Ⅱ and Ⅲ） for screening the angiogenic effect of ICAM-1 by adding different concentrations of ICAM-1 （0.1, 0.2 and 0.3 μg/μL） 5 μL into the chick embryo CAMs on the day 10 after incubation for every subgroup; Anti-ICAM-1 group A （divided into 2 subgroups, Ⅰ and Ⅱ） by adding different concentrations of Anti-ICAM-1 （1：100, 1：50） 5 μL into the chick embryo CAMs on the day 10 after incubation for every subgroup to evaluate the effect of ICAM-1 on the survival of microvessels through observing whether Anti-ICAM-1 could induce involution of the microvessels on CAMs; Anti-ICAM-1 group B （divided into 2 subgroups, Ⅰ and Ⅱ ） by adding different concentrations of Anti-ICAM-1 （1：100, 1：50） 5 μL into the chick embryo CAMs on the day 6 after incubation for every subgroup to evaluate whether ICAM-1 involved in embryonic angiogenesis through observing the growth of microvessels on CAMs; Control group： ICAM-1 or Anti-ICAM-1 was substituted by PBS 5 μL on the day 10 or day 6 after incubation. Three days later, the CAMs were photographed in vivo, excised, sectioned and the number of microvessels was counted. In ICAM-1 group, there was increased number of microvessels arranged radially with ＂spoked-wheel＂ pattern around the gelatin sponges. The new microvessels growing perpendicularly to gelatin sponges were observed. The number of the microvessels growing in the CAM mesenchymes around the sponges in 3 subgroups was higher than that in control group （P〈0.01）, however, there was no significant difference among the 3 subgroups （P〉0.05）. In anti-ICAM-1 group A, the radially arranged microvessels were very unclear around the sponges contrast to that of ICAM-1 group. Few new microvessels were detected in the center of the sponges. The number of the microvessels growing in the CAM mesenchymes around the sponges in subgroup Ⅱ was lower than that in control group （P〈0.01）. There was no significant difference in the number of the microvessels around the sponges between subgroup I and control group （P〉0.05）. In anti-ICAM-1 group B, the radially arranged microvessels were very unclear around the sponges contrast to that of control grouμ New microvessels were very scarce in the center of the sponges. The number of the microvessels growing in the CAM mesenchymes around the sponges in the 2 subgroups were less than that in control group （P〈0.01）, and there was significant difference between the 2 subgroups （P〈0.05）. It was suggested that ICAM-1 could induce angiogenesis and support the survival of microvessels, and ICAM-1 was involved in embryonic angiogenesis.展开更多
Modern strains of broiler chickens are selected for fast growth and are marketed anywhere from 36 to 49 days after a21-day incubational period. For a viable healthy chick, all the necessary nutrients required for grow...Modern strains of broiler chickens are selected for fast growth and are marketed anywhere from 36 to 49 days after a21-day incubational period. For a viable healthy chick, all the necessary nutrients required for growth and development must be provided by the hen through the fertilized egg. The current feeding strategies for improved growth, health and productivity are targeted towards chicks after hatching. Considering the fact that developing chick embryo spends over 30 % of its total life span inside the hatching egg relying on nutrients deposited by the breeder hen, investigations on nutritional needs during pre-hatch period will improve embryonic health, hatchability and chick viability. In this context, investigations on hatching egg lipid quality is of utmost importance because, during incubation, egg fat is the major source of energy and sole source of essential omega-6（n-6） and omega-3（n-3） fatty acids to the chick embryo.Due to the unique roles of n-3 and n-6 fatty acids in growth, immune health, and development of central nervous system, this review will focus on the role of early exposure to essential fatty acids through maternal diet and hatching egg and its impact on progeny in meat-type broiler chickens.展开更多
AntiA3typeinfluenza virus activity and toxicity for chick embryo of some heteropoly compounds containing rare earth elements were investigated. The results demonstrate that these heteropoly compounds directly inactiva...AntiA3typeinfluenza virus activity and toxicity for chick embryo of some heteropoly compounds containing rare earth elements were investigated. The results demonstrate that these heteropoly compounds directly inactivate the A3type influenza virus, and the inhibition rate of K15)2]15H2O for the A3type influenza virus is more than 90% with antivirus index TI 69. The result is obviously superior to that of the positive reference drug ribavirin.展开更多
Chick viability is known to be an important factor determining profitability of the poultry industry. Chick embryo tissues contain a high proportion of highly polyunsaturated fatty acids in the lipid fraction and ther...Chick viability is known to be an important factor determining profitability of the poultry industry. Chick embryo tissues contain a high proportion of highly polyunsaturated fatty acids in the lipid fraction and therefore need antioxidant defence. The antioxidant system of the developing embryo and newly hatched chick includes the antioxidant enzymes(superoxide dismutase, glutathione peroxidase, catalase), water-soluble antioxidants(ascorbic acid, taurine, carnitine, glutathione, etc.), fat-soluble antioxidants(vitamin E, carotenoids, coenzyme Q) as well as selenium(Se). In fact, the high levels of endogenous antioxidants within the egg and embryonic tissues can clearly serve as a major adaptive mechanism for the protection of the tissue during the oxidative stress experienced at hatching. It has been shown that among different nutrients in the maternal diet which could significantly affect chick embryo development and their viability in the early posthatch life, natural antioxidants have been suggested to play a central role. Our data indicate that increased supplementation of the maternal diet can substantially increase concentrations of vitamin E, carotenoids(especially canthaxanthin) and Se in developing chick tissues and significantly decrease susceptibility to lipid peroxidation being effective nutritional tools to deal with various commercial stresses in poultry production.展开更多
Inflammatory,proliferative and remodeling phases constitute a cutaneous wound healing program.Therapeutic applications and medication are available;however,they commonly are comprised of fortified preservatives that m...Inflammatory,proliferative and remodeling phases constitute a cutaneous wound healing program.Therapeutic applications and medication are available;however,they commonly are comprised of fortified preservatives that might prolong the healing process.Chick early amniotic fluids(ceAF)contain native therapeutic factors with balanced chemokines,cytokines and growth-related factors;their origins in principle dictate no existence of harmful agents that would otherwise hamper embryo development.Instead,they possess a spectrum of molecules driving expeditious mitotic divisions and possibly exerting other functions.Employing both in vitro and in vivo models,we examined ceAF's therapeutic potentials in wound healing and found intriguing involvement of transient senescence,known to be intimately intermingled with Senescence Associated Secretory Phenotypes(SASP)that function in addition to or in conjunction with ceAF to facilitate wound healing.In our cutaneous wound healing models,a low dose of ceAF exhibited the best efficacies;however,higher doses attenuated the wound healing presumably by inducing p16 expression over a threshold.Our studies thus link an INK4/ARF locus-mediated signaling cascade to cutaneous wound healing,suggesting therapeutic potentials of ceAF exerting functions likely by driving transient senescence,expediting cellular proliferation,migration,and describing a homeostatic and balanced dosage strategy in medical intervention.展开更多
基金financially supported by the Ministry of Education,Science and Culture,Japanthe Society for the Promotion of Science(JSPS)+1 种基金the Sumitomo Foundationthe Nissan Science Foundation
文摘Aim:To examine the transfection of exogenous genes into chick embryos,applying the characteristics of avianleukosis vires(ALV)-induced chicken B cell line DT40 to the production of chimeric birds.Methods:The DT40cells incorporated with exogenous gene(lacZ constructs encoding Escherichia coliβ-galactosidase:β-gal)were intro-duced into chick embryos by the injection of cells into stage X blastoderm.Manipulated eggs were incubated for 3(trial1)or 6(trial 2)days,and the expression of lacZ DNA was detected by a histochemical staining method ofβ-galactosi-dase and polymerase chain reaction(PCR)analysis.Results:The survival rates of the manipulated embryos incu-bated for 3 days(stage 18-20:trial 1)and 6 days(stage 28,30:trial 2)were about 42%and 38%,respectively.The expression rates of the lacZ gene in the embryos in the trials 1 and 2 were about 60%and 23%,respectively,forthe survived embryos.Conclusion:The rate of embryonic viability and expression rate of introduced genes were notso high,but it suggested the possibility of utilizing the DT40 cells as a vector for carrying exogenous genes into chickembryos.
文摘The effects of thyroxine and atropine in ameliorating phosphamidon intoxication in chick embryos was studied. Treatment of phosphamidon significantly enhanced the moriality and abnormalityrates, decreased the average body weights, and cholinesterase activity in chick embryos. When thyroxine was administered to the phosphamidon intoxicated embryos, the above parameters changedsignificantly, indicating an ameliorating effect of thyroxine against phosphamidon intoxication in chick embryos. The combined thyroxine and atropine therapy did not further improve the ameliorating effect. Since in many respects chick embryo development parallels that of mammalian embryos,a short-term use of thyroxine as a protective agent against organophosphate toxicity might be useful
基金supported by DBT-BUILDER-Cat III(Grant number:BT/INF/22/SP41403/2021)Gujarat State Biotechnology Mission(GSBTM)Gandhinagar,India,for financial assistance(Grant number:GSBTM/JD(R&D)/618/21e22/1224,Date:December 28,2021).
文摘Pesticides are reported to be teratogenic for non-target species.Our studies have unraveled the teratogenicity of 50%Chlorpyrifos&5%Cypermethrin combination(Ci)in developing chick embryos.A sublethal dose of this combination when administered to chick embryos,caused several developmental anomalies,with defects in eye development being frequent.Eye development begins at an early embryonic stage,with Sonic hedgehog(Shh)serving as a crucial signaling molecule.Shh plays a pivotal role in the early development of multiple organs,including the eye,by interacting with Pax6 and other regulatory molecules to guide the proper patterning of the eye.Thus,we hypothesized that Ci administration may lead to alteration in Shh expression which subsequently hampers downstream signaling molecules potentially contributing to congenital eye defects.Morphological,anatomical,histological,transcriptional and protein level analyses at various stages(Days 1,2,4 and 10)were carried out to evaluate the hypothesis.The results revealed a remarkable alteration of key regulators in treated embryos compared to control,providing insights into plausible causative mechanisms underlying Ciinduced congenital eye defects.
文摘Aim: This study was designed to investigate the effect of busulfan treatment on the proliferation of chicken primordialgerm cells (PGCs) in vivo, focusing on the preferential settlement of PGCs onto the germinal ridges of chicken em-bryos. Methods: Busulfan (250 ng/egg) was injected into the egg white of freshly oviposited fertilized eggs, whichwere then incubated. Embryonic development and viability were examined, and exogenous PGCs collected from embry-onic blood vessels were injected into the germinal crescent region of recipient embryos. The number of PGCs residedonto germinal ridges of the right and left sides were compared. Results: Busulfan had a slight harmful effect on theembryo viability and the PGCs proliferation. The number of PGCs resided onto the left side of germinal ridges wasslightly higher as compared with the right side. Conclusion: Busulfan suppressed the viability of embryos and the pro-liferation of endogenous PGCs in the recipient embryos. However, the number of exogenous PGCs proliferated washigher in embryos treated with busulfan than those without busulfan. Data also suggest the possibility of a preferentialresidence of PGCs toward the left side of the germinal crescent region as compared with the fight, which may be due toa more advanced functional development of the left gonad than the right. (Asian J Androl 1999 Dec; 1: 187-190)
基金supported by the National Natural Science Foundation of China (31472087)the Research and Innovation Program for Graduate Cultivation of Jiangsu Proviance,China in 2010
文摘In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation. Transferring exogenous substances into chicken embryos for producing medical antibodies has been widely used in the production practice. However, there are few studies about the effect of the different injection site and dosage on chicken embryos. The aim of this study was to explore the effects of different injection sites and dosages on chicken embryo hatching rate and development, so as to provide a basis for further studies using the chicken embryo model. Freshly laid eggs （Rugao yellow chicken） were injected with different doses of saline at the tip, equatorial plane and the blunt end of the egg shell, respectively. Egg hatching rate was recorded and compared among injection sites and different doses. A trypan blue stain was also injected at the aforementioned sites and the growth of chicken embryos was observed. The SPSS （statistical package for the social science） software was used to analyze the relationship between the chicken eggs hatching rate and the different injection sites or the different dosages. The experimental results showed that there were significant differences on egg hatching rates among the different injection sites and doses （P〈0.05）. The hatchability of the blunt end injection group was significantly higher than that of the other two sites. The egg hatching rate decreased with increased saline doses. The egg hatching rate of the 100 pL saline injection group was higher than the 200 and 300 μL dosage groups. Ultimately, we suggest that the optimal chicken embryo injection process is during early development, at the blunt end site with a dose less than 100 μL to minimize damage to the egg.
基金supported by the Key International Cooperation Program of the National Natural Science Foundation of China (31110103916)the National Natural Science Foundation of China (31272465)+1 种基金the Agricultural Science and Technology Innovation Program,China (ASTIP-IAS08)the China Agriculture Research System (CARS-42)
文摘In the present study, the effect of manganese（Mn） on antioxidant status and the expression of the manganese superoxide dismutase（MnSOD） gene in cultured primary myocardial cells collected from the chick embryos was investigated. The hypothesis that Mn supplementation would enhance the expression of MnSOD in cultured primary myocardial cells of chick embryos was tested. Eggs collected from Mn-depleted Arbor Acres laying breeder hens were incubated for 10 days and then myocardial cells were isolated and cultivated for 8 days. The embryonic myocardial cells on day 6 were treated with Mn in the cell culture medium at different time points when the proportion of cells showing spontaneous contraction was over 95% after the 3-day primary culture. A completely randomized design involving a 3 Mn levels（0, 0.5 and 1.0 mmol L^（-1））×3 incubation time points（12, 24 and 48 h） factorial arrangement of treatments（n=6） was used in the current experiment. The results showed that MnSOD activity and m RNA expression level were induced by Mn and increased with incubation time, which supported the hypothesis that Mn would enhance the expression of the MnSOD gene, and thus might protect myocardial cells from oxidative stress during the chick embryonic development.
基金National Natural Science Foundation of China （#90208011, #30300174, #30070856 , #30421005） National Key Basic Research and Development Program of China （#2002CB713802 , #2005CB522700） Shanghai Key Project of Basic Science Research （#04DZ14005 , #04DZ05608）.
文摘Members of the basic helix-loop-helix （bHLH） gene family play important roles in vertebrate neurogenesis. In this study, confocal microscopy-based fluorescence resonance energy transfer （FRET） is used to monitor bHLH protein-protein interactions under various physiological conditions. Tissue-specific bHLH activators, NeuroD 1, Mash 1, Neurogenin 1 （Ngn 1）, Neurogenin2 （Ngn2）, and ubiquitous expressed E47 protein are tagged with enhanced yellow fluorescence protein （EYFP） and enhanced cyan fluorescence protein （ECFP）, respectively. The subcellular localization and mobility ofbHLH fusion proteins are examined in HEK293 cells. By transient transfection and in ovo electroporation, four pairs of tissue-specific bHLH activators and E47 protein are over-expressed in HEK293 cells and developing chick embryo neural tube. With the acceptor photobleaching method, FRET could be detected between these bHLH protein pairs in the nuclei of transfected cells and developing neural tubes. Mashl/E47 and Ngn2/E47 FRET pairs show higher FRET efficiencies in the medial and the lateral half of chick embryo neural tube, respectively. It suggests that these bHLH protein pairs formed functional DNA-protein complexes with regulatory elements of their downstream target genes in the specific regions. This work will help one understand the behaviours of bHLH factors in vivo.
文摘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.
文摘Thyroid hormone deficiency was created artificially in chick embryos by injecting propyl-thiouracil (PTU).The tubulin was quantified by ~3H-colchicine assay(expressed as colchicine binding activity).Thyroid hormone deficiency resulted in 16％ to 28％ decline of the tubulin level in the developing chick brain from 15 to 19 days of embryonic age as compared with the control,whereas the total protein amount was not significantly affected.It suggests that thyroid hormone specifically affected the synthesis of brain tubulin.
文摘[Objective] This study was to investigate the effect of forsythiaside A added in chick embryo kidney cells (CEKs), on the changes in expression of interferon α(IFN-α) and mRNA expression level of correlated factors in JAK-STAT pathway. [Methods] Three levels of forsythiaside (100, 200, 400 μg/ml) were adopted to treat the experimental materials, then the expression levels of IFN-α and correlated factors in JAK-STAT pathway were detected by real-time RT-PCR at the transcriptional level (mRNA) and by Western blot at the translation level(IFN-α protein). [Result] Compared with the control group (untreated group), Application of forsythiaside A not only significantly increased the expression of IFN-α in treated CEKs (P<0.05) , but also up-regulated the expression of STAT1, JAK1, IFNAR1, IFNAR2, IRF1 and IRF7, the correlated factors in JAK-STAT pathway. [Conclusion] Forsythiaside A induced the expression of IFN-α in CEKs, and can positively regulate the JAK-STAT signaling pathway significantly.
基金the National Natural Science Foundation of China,No.81160395
文摘Carbon nanotubes can carry protein into cells to induce biological effects. Amino-functionalized carbon nanotubes are soluble and biocompatible, have high reactivity and low toxicity, and can help promote nerve cell growth. In this study, amino-functionalized ethylenediamine-treated multi-walled carbon nanotubes were used to prepare carbon nanotubes-nerve growth factor complexes by non-covalent grafting. The physicochemical properties, cytotoxicity to PC12 and chick embryo dorsal root ganglion, and biological activity of the carbon nanotubes-nerve growth factor complexes were investigated. The results showed that amino functionalization improved carbon nanotubes-nerve growth factor complex dispersibility, reduced their toxicity to PC12 cells, and promoted PC 12 cell differentiation and chick embryo dorsal root ganglion.
基金This project was supported by a grant from the National Natural Sciences Foundation of China (No. 30271345).
文摘In order to investigate the angiogenic effect of intercellular adhesion molecule-1 （ICAM-1）, two parts of experiment were performed. Chick embryo chorioallantoic membrane （CAM） assay was used for in vivo angiogenic research. The chick embryos were divided into 4 groups： ICAM-1 group （divided into 3 subgroups, Ⅰ, Ⅱ and Ⅲ） for screening the angiogenic effect of ICAM-1 by adding different concentrations of ICAM-1 （0.1, 0.2 and 0.3 μg/μL） 5 μL into the chick embryo CAMs on the day 10 after incubation for every subgroup; Anti-ICAM-1 group A （divided into 2 subgroups, Ⅰ and Ⅱ） by adding different concentrations of Anti-ICAM-1 （1：100, 1：50） 5 μL into the chick embryo CAMs on the day 10 after incubation for every subgroup to evaluate the effect of ICAM-1 on the survival of microvessels through observing whether Anti-ICAM-1 could induce involution of the microvessels on CAMs; Anti-ICAM-1 group B （divided into 2 subgroups, Ⅰ and Ⅱ ） by adding different concentrations of Anti-ICAM-1 （1：100, 1：50） 5 μL into the chick embryo CAMs on the day 6 after incubation for every subgroup to evaluate whether ICAM-1 involved in embryonic angiogenesis through observing the growth of microvessels on CAMs; Control group： ICAM-1 or Anti-ICAM-1 was substituted by PBS 5 μL on the day 10 or day 6 after incubation. Three days later, the CAMs were photographed in vivo, excised, sectioned and the number of microvessels was counted. In ICAM-1 group, there was increased number of microvessels arranged radially with ＂spoked-wheel＂ pattern around the gelatin sponges. The new microvessels growing perpendicularly to gelatin sponges were observed. The number of the microvessels growing in the CAM mesenchymes around the sponges in 3 subgroups was higher than that in control group （P〈0.01）, however, there was no significant difference among the 3 subgroups （P〉0.05）. In anti-ICAM-1 group A, the radially arranged microvessels were very unclear around the sponges contrast to that of ICAM-1 group. Few new microvessels were detected in the center of the sponges. The number of the microvessels growing in the CAM mesenchymes around the sponges in subgroup Ⅱ was lower than that in control group （P〈0.01）. There was no significant difference in the number of the microvessels around the sponges between subgroup I and control group （P〉0.05）. In anti-ICAM-1 group B, the radially arranged microvessels were very unclear around the sponges contrast to that of control grouμ New microvessels were very scarce in the center of the sponges. The number of the microvessels growing in the CAM mesenchymes around the sponges in the 2 subgroups were less than that in control group （P〈0.01）, and there was significant difference between the 2 subgroups （P〈0.05）. It was suggested that ICAM-1 could induce angiogenesis and support the survival of microvessels, and ICAM-1 was involved in embryonic angiogenesis.
基金the National Research Initiative of the USDA Cooperative State Research,Education and Extension Service,grant number2004-35204-14654,Oregon State University Experiment Station Hatch fund,Oregon State University Animal Health Fund,and Walther H.Ott Professorship in Poultry Science awarded to G.Cherian
文摘Modern strains of broiler chickens are selected for fast growth and are marketed anywhere from 36 to 49 days after a21-day incubational period. For a viable healthy chick, all the necessary nutrients required for growth and development must be provided by the hen through the fertilized egg. The current feeding strategies for improved growth, health and productivity are targeted towards chicks after hatching. Considering the fact that developing chick embryo spends over 30 % of its total life span inside the hatching egg relying on nutrients deposited by the breeder hen, investigations on nutritional needs during pre-hatch period will improve embryonic health, hatchability and chick viability. In this context, investigations on hatching egg lipid quality is of utmost importance because, during incubation, egg fat is the major source of energy and sole source of essential omega-6（n-6） and omega-3（n-3） fatty acids to the chick embryo.Due to the unique roles of n-3 and n-6 fatty acids in growth, immune health, and development of central nervous system, this review will focus on the role of early exposure to essential fatty acids through maternal diet and hatching egg and its impact on progeny in meat-type broiler chickens.
文摘AntiA3typeinfluenza virus activity and toxicity for chick embryo of some heteropoly compounds containing rare earth elements were investigated. The results demonstrate that these heteropoly compounds directly inactivate the A3type influenza virus, and the inhibition rate of K15)2]15H2O for the A3type influenza virus is more than 90% with antivirus index TI 69. The result is obviously superior to that of the positive reference drug ribavirin.
文摘Chick viability is known to be an important factor determining profitability of the poultry industry. Chick embryo tissues contain a high proportion of highly polyunsaturated fatty acids in the lipid fraction and therefore need antioxidant defence. The antioxidant system of the developing embryo and newly hatched chick includes the antioxidant enzymes(superoxide dismutase, glutathione peroxidase, catalase), water-soluble antioxidants(ascorbic acid, taurine, carnitine, glutathione, etc.), fat-soluble antioxidants(vitamin E, carotenoids, coenzyme Q) as well as selenium(Se). In fact, the high levels of endogenous antioxidants within the egg and embryonic tissues can clearly serve as a major adaptive mechanism for the protection of the tissue during the oxidative stress experienced at hatching. It has been shown that among different nutrients in the maternal diet which could significantly affect chick embryo development and their viability in the early posthatch life, natural antioxidants have been suggested to play a central role. Our data indicate that increased supplementation of the maternal diet can substantially increase concentrations of vitamin E, carotenoids(especially canthaxanthin) and Se in developing chick tissues and significantly decrease susceptibility to lipid peroxidation being effective nutritional tools to deal with various commercial stresses in poultry production.
文摘Inflammatory,proliferative and remodeling phases constitute a cutaneous wound healing program.Therapeutic applications and medication are available;however,they commonly are comprised of fortified preservatives that might prolong the healing process.Chick early amniotic fluids(ceAF)contain native therapeutic factors with balanced chemokines,cytokines and growth-related factors;their origins in principle dictate no existence of harmful agents that would otherwise hamper embryo development.Instead,they possess a spectrum of molecules driving expeditious mitotic divisions and possibly exerting other functions.Employing both in vitro and in vivo models,we examined ceAF's therapeutic potentials in wound healing and found intriguing involvement of transient senescence,known to be intimately intermingled with Senescence Associated Secretory Phenotypes(SASP)that function in addition to or in conjunction with ceAF to facilitate wound healing.In our cutaneous wound healing models,a low dose of ceAF exhibited the best efficacies;however,higher doses attenuated the wound healing presumably by inducing p16 expression over a threshold.Our studies thus link an INK4/ARF locus-mediated signaling cascade to cutaneous wound healing,suggesting therapeutic potentials of ceAF exerting functions likely by driving transient senescence,expediting cellular proliferation,migration,and describing a homeostatic and balanced dosage strategy in medical intervention.
