In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Poin...In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point.展开更多
The exchange of oxygen (O2) and carbon dioxide (CO2) within an incubator has a significant impact on embryonic development (ED) and hatching processes. This study examines the influence of non-ventilation (NV) conditi...The exchange of oxygen (O2) and carbon dioxide (CO2) within an incubator has a significant impact on embryonic development (ED) and hatching processes. This study examines the influence of non-ventilation (NV) conditions during the first ten days of incubation at high altitudes on Leghorn hens hatching eggs. Five hundred four hatching eggs were equally divided into three treatment groups and placed in twelve incubators (R = 4). The first group was subjected to standard ventilated conditions (V) during the setting phase. The ventilation inlet holes of the remaining incubators in the NV treatments were closed with either micropore (M) or polypropylene (P) tape, referred to as NVM and NVP groups, respectively. These two different airtight settings were intended to allow for a gradual rise in CO2 naturally generated by the embryos. Results indicate that carbon dioxide concentration gradually increased during the first half of incubation, reaching 1.42% in the NVM group and 1.20% in the NVP group, while the V condition group remained at 0.15%. From 10 days of incubation onwards, normal V conditions were restored in all incubators. The highest hatchability of fertile eggs (HFE) was shown by the NVP group (55.7%), followed by the V (52.6%) and NVM (38.6%) groups. The NVP group showed a greater yolk-free body mass (YFBM) from 10 days of incubation until the hatch basket transfer. NV conditions during the first 10 days of incubation at high altitude produced higher YFBM with gradually decreasing yolk sac mass. In comparison to the NVM and V conditions, the particular NVP condition showed a beneficial impact on the quality of hatched chicks. Sustaining NVP condition (1.2% of CO2) throughout the first half of incubation at high altitude generated the optimal environment in the incubator ensuring the best hatchability results. This study highlights how important it is for hatchery managers to recognize the influence of low O2 and high levels of CO2 on the development trajectories of Leghorn embryos during early incubation at high altitudes.展开更多
[Objective] This study aimed to investigate the distribution law of different goblet cells in the intestinal tracts of African ostrich chicks. [Method] Alcian blue/pe- riodic acid-schiff reaction (AB/PAS) was adopte...[Objective] This study aimed to investigate the distribution law of different goblet cells in the intestinal tracts of African ostrich chicks. [Method] Alcian blue/pe- riodic acid-schiff reaction (AB/PAS) was adopted to observe and analyze the types and distribution of goblet cells in the intestinal tracts of ostrich chicks. Acid mu- copolysaccharide could be stained blue with alcian blue (AB), and neutral mu- copolysaccharide could be stained red with periodic acid-schiff reagent (PAS). [Result] According to AB/PAS results, goblet cells in the intestinal tracts were divided in- to four types: TypeⅠ was pure red, with AB negative result and PAS positive result containing neutral mucoitin; type Ⅱ was pure blue, with AB positive result and PAS negative result containing acidic mucoitin; type Ⅲ was purple reddish, with PAS posi- tive result greater than AB; typeⅣ was purple blue, with AB positive result greater than PAS. Large quantities of goblet cells were found in the intestinal tracts of os- trich chicks, mostly type III and IV.The quantities of goblet cells were decreased gradually in the duodenum, jejunum and ileum, while the quantities were increased in the cecum, colon and rectum. The goblet cells in the large intestine are more than that in the small intestine. The most quantities of goblet cells were contained in rectum. [Conclusion] These results indicate that the distribution of goblet cells is closely related with the structure and function of intestinal tracts. The mucus secret- ed by the goblet Cells plays a series of important roles in the digestion and mucosal immunization.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
[Objective] This study aimed to investigate the differences in morphological structure of tibias between sick and normal ostrich chicks. [Method] Normal and sick ostrich chicks aged 90 days were used in this research ...[Objective] This study aimed to investigate the differences in morphological structure of tibias between sick and normal ostrich chicks. [Method] Normal and sick ostrich chicks aged 90 days were used in this research for bone mineral density determination, bone demineralization paraffin section preparation (HE staining), bone abrasive disc preparation and scanning electron microscopy (SEM) observation, to analyze the differences in microstructure and ultrastructure of tibias between sick ostrich chicks and normal ones. [Result] Bone mineral density of ostrich chicks suffering from leg disease was much lower than that of the normal ones. Compared with normal tibias, less trabeculae were observed in sick tibias, which were attenuated and began to disappear. In addition, trabeculae micro-fracture could be observed under scanning electron microscope; resorption pits on bone slices formed by osteoclast could be observed under scanning electronic microscope. [Conclusion] These results indicate that the sick tibias all have lower bone density and trabeculae microfracture phenomenon in tibias with different diseases, which might be resulted from osteoporosis.展开更多
An experiment was conducted to investigate the effect of dietary supplementation of xylo-oligosaccharides(XOS) on growth performance, meat quality, immune functions, duodenal morphology and intestinal microbial popu...An experiment was conducted to investigate the effect of dietary supplementation of xylo-oligosaccharides(XOS) on growth performance, meat quality, immune functions, duodenal morphology and intestinal microbial populations of broilers fed a conventional corn-soybean meal basal diet. A total of 450 1-day-old commercial Arbor Acres male broiler chicks were randomly allocated by bodyweight to 1 of 5 treatments with 6 replicate cages(15 broilers per cage) for each of 5 treatments in a completely randomized design. Chicks were fed the basal corn-soybean meal diets supplemented with 0, 25, 50, 75, or 100 mg of XOS kg–1 of diet, respectively, for an experimental duration of 42 days. The results showed that supplementation of XOS affected feed conversion rate(feed/gain, F/G) during days 22–42 and 1–42(P〈0.03), drip loss in thigh muscle(P=0.02), and duodenal crypt depth(P=0.005) on day 42, but had no effect(P〉0.05) on all other measured indices. The chicks fed the diet supplemented with 100 mg of XOS kg–1 had the lowest(P〈0.05) F/G and drip loss in thigh muscle. The drip loss in thigh muscle decreased linearly(P=0.003) as the supplemented XOS increased. Duodenal crypt depth decreased(P〈0.05) at the supplemental level of 75 mg of XOS kg–1. The results indicate that dietary supplementations of 75 and 100 mg of XOS kg–1 are beneficial to broilers fed a conventional corn-soybean meal diet.展开更多
Background:Prenatal nutrition is crucial for embryonic development and neonatal growth,and has the potential to be a main determinant of life-long health.In the present study,we used a layer chick model to investigate...Background:Prenatal nutrition is crucial for embryonic development and neonatal growth,and has the potential to be a main determinant of life-long health.In the present study,we used a layer chick model to investigate the effects of in ovo feeding(IOF)of L-arginine(Arg)on growth,intestinal development,intestinal microbiota and metabolism.The treatments included the non-injected control,saline-injected control,and saline containing 2,6,or 10 mg Arg groups.Results:IOF Arg increased early intestinal index and villus height,and enhanced uptake of residual yolk lipid,contributing to subsequent improvement in the early growth performance of chicks.Prenatal Arg supplementation also increased the early microbialα-diversity,the relative abundance of Lactobacillales and Clostridiales,and decreased the relative abundance of Proteobacteria of cecum in chicks.Furthermore,the shift of cecal microbiota composition and the colonization of potential probiotics were accelerated by IOF of Arg.Simultaneously,metabolomics showed that metabolisms of galactose,taurine-conjugated bile acids and lipids were modulated to direct more energy and nutrients towards rapid growth of intestine at the beginning of post-hatch when embryos received IOF of Arg.Conclusions:Prenatal Arg supplementation showed beneficial effects on the early intestinal development,cecal microbiota and host metabolism of layer chicks,contributing to subsequent improvement in the early growth performance.These findings provide new insight into the role of IOF of Arg in the establishment of the gut microbiota of newly-hatched layer chicks,and can expand our fundamental knowledge about prenatal nutrition,early bacterial colonization and intestinal development in neonate.展开更多
AIM: To evaluate the effect of antisense oligonucleotide targeting midkine (MK-AS) on angiogenesis in chick chorioallantoic membrane (CAM) and in situ human hepatocellular carcinoma (HCC). METHODS: An in situ human he...AIM: To evaluate the effect of antisense oligonucleotide targeting midkine (MK-AS) on angiogenesis in chick chorioallantoic membrane (CAM) and in situ human hepatocellular carcinoma (HCC). METHODS: An in situ human hepatocellular carcinoma (HCC) model and CAM assay were used in this experiment. The effect of MK-AS on angiogenesis was evaluated by cell proliferation assay and hematoxylin- eosin (HE) staining. RESULTS: MK-AS significantly inhibited human umbilical vein endothelial cells (HUVEC) and in situ human HCC growth. At the same time, MK-AS suppressed the angiogenesis both in human hepatocellular carcinoma cell line (HEPG2)-induced CAM and in situ human HCC tissues. CONCLUSION: MK-AS is an effective antiangiogenesis agent in vivo.展开更多
Background:Cytochrome b5 reductase 2(CYB5R2) is a potential tumor suppressor that inhibits cell proliferation and motility in nasopharyngeal carcinoma(NPC).Inactivation of CYB5R2 is associated with lymph node metastas...Background:Cytochrome b5 reductase 2(CYB5R2) is a potential tumor suppressor that inhibits cell proliferation and motility in nasopharyngeal carcinoma(NPC).Inactivation of CYB5R2 is associated with lymph node metastasis in NPC.This study aimed to explore the mechanisms contributing to the anti-neoplastic effects of CYB5R2.Methods:Polymerase chain reaction(PCR) assays were used to analyze the transcription of 84 genes known to be involved in representative cancer pathways in the NPC cell line HONE1.NPC cell lines CNE2 and HONE1 were transiently transfected with CYB5R2,and data was validated by real-time PCR.A chick chorioallantoic membrane(CAM)embryo model was implanted with CYB5R2-expressing CNE2 and HONE1 cells to evaluate the effect of CYB5R2 on angiogenesis.An immunohistochemical assay of the CAM model was used to analyze the protein expression of vascular endothelial growth factor(VEGF).Results:In CYB5R2-transfected NPC cells,PCR assays revealed up-regulated mRNA levels of Fas cell surface death receptor(FAS),FBJ murine osteosarcoma viral oncogene homolog(FOS),phosphoinositide-3-kinase regulatory subunit 1(PIK3R1),integrin beta 3(ITGB3),metastasis suppressor 1(MTSSl),interferon beta 1(IFNB1),and cyclin-dependent kinase inhibitor 2A(CDKN2A) and down-regulated levels of integrin beta 5(ITGB5),insulin-like growth factor 1(IGF1),TEK tyrosine kinase(TEK),transforming growth factor beta receptor 1(TGFBRl),and VEGF.The angiogenesis in the CAM model implanted with CYB5R2-transfected NPC cells was inhibited.Down-regulation of VEGF by CYB5R2 in NPC cells was confirmed by immunohistochemical staining in the CAM model.Conclusion:CYB5R2 up-regulates the expression of genes that negatively modulate angiogenesis in NPC cells and down-regulates the expression of VEGF to reduce angiogenesis,thereby suppressing tumor formation.展开更多
AIM: To investigate the role of vasoactive intestinal peptide(VIP) in form-deprivation myopia(FDM).METHODS: FDM was created in three groups of eight chicks by placing a translucent diffuser on their right eyes.I...AIM: To investigate the role of vasoactive intestinal peptide(VIP) in form-deprivation myopia(FDM).METHODS: FDM was created in three groups of eight chicks by placing a translucent diffuser on their right eyes.Intravitreal injections of saline and VIP were applied once a day into the occluded eyes of groups 2 and 3,respectively.Retinoscopy and axial length(AL) measurements were performed on the first and 8^th days of diffuser wear.The retina mR NA levels of the VIP receptors and the ZENK protein in right eyes of the three groups and left eyes of the first group on day 8 were determined using real time polymerase chain reaction(PCR).RESULTS: The median final refraction(D) in right eyes were-13.75(-16.00,-12.00),-11.50(-12.50,-7.50),and-1.50(-4.75,-0.75) in groups 1,2,and 3,respectively(P〈0.001).The median AL(mm) in right eyes were 10.65(10.00,11.10),9.90(9.70,10.00),and 9.20(9.15,9.25) in groups 1,2,and 3,respectively(P〈0.001).The median delta-delta cycle threshold(CT) values for the VIP2 receptors were 1.07(0.82,1.43),1.22(0.98,1.65),0.29(0.22,0.45) in right eyes of groups 1,2,and 3,and 1.18(0.90,1.37) in left eyes of group 1,respectively(P=0.001).The median delta-delta CT values for the ZENK protein were 1.07(0.63,5.03),3.55(2.20,5.55),undetectable in right eyes of groups 1,2,and 3 and 1.89(0.21,4.73) in left eyes of group 1,respectively(P=0.001).CONCLUSION: VIP has potential inhibitory effects in the development of FDM.展开更多
A study was under taken to investigate the effect of dietary supplementations of humic acid and esterified glucomannan) on broiler performance and the morphological measurements of small intestine. Two hundred and ten...A study was under taken to investigate the effect of dietary supplementations of humic acid and esterified glucomannan) on broiler performance and the morphological measurements of small intestine. Two hundred and ten day old broiler chicks were weighed and randomly assigned to seven treatment groups in triplicate. The dietary treatments included T1) control (basal diet without any additives), T2) basal diets supplemented with 0.1% humic acid, T3) basal diets supplemented with 0.2% humic acid, T4) basal diets supplemented with 0.3% humic acid, T5) basal diets supplemented with 0.1% esterified glucomannan, T6) basal diets supplemented with 0.2% esterified glucomannan and T7) basal diets supplemented with 0.3% esterified glucomannan. Different parameters including body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and morphology of small intestine were evaluated during six weeks of experimental period. According to the results, at the end of experimental period, the highest average BWG were recorded in T4 group (fed with 0.3% humic acid), compared to control (T1) and other experimental groups (p < 0.05). Where as, the highest body weight gain were observed during starter period in treatment 7 (fed with 0.3% esterified glucomannan) as compare to other experimental groups (p < 0.05). Statistically, feed intake remained unaffected during the experimental period in all the treatment groups. However, the lowest and the highest feed intake were observed numerically within treatments T4 and T1 with 4229.70 g and 4362.30 g, respectively. Addition of dietary supplements used in the study appeared to have significant effect on the morphology of the small intestine (jejunum mucosal development) of the broilers in different treatment groups. Compared to control group, the inclusion of either humic acid or esterified glucomannon decreased (p < 0.01) the crypt depth and increased villus height respectively (p < 0.05). More ever, the diet supplements with humic acid 0.3% (T4) decreased crypt depth compared to esterified glucomannan and control. The dietary supplementations resulted in an increase in the villus height of intestinal mucosa of broilers. The increase in the villus height was associated with improvement of growth performance for both humic acid and esterified glucomannan. Based on our results it appeared that humic acid and esterified glucomannan can be used as a growth promoter in broiler diets and they can improve the gut health too.展开更多
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
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 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
Vascular endothelial growth factors(VEGFs) respectively bind to each of three receptor tyrosine kinases(RTKs),known as Flt-1,KDR and Flt-4.Since VEGFs and their respective families of receptor tyrosine kinases(VE...Vascular endothelial growth factors(VEGFs) respectively bind to each of three receptor tyrosine kinases(RTKs),known as Flt-1,KDR and Flt-4.Since VEGFs and their respective families of receptor tyrosine kinases(VEGFRs) are critical proteins which can regulate vascular development during angiogenesis,we decided to explore the inhibitory effects of soluble kinase insert domain-containing receptor(sKDR) on endothelial cells and angiogenesis.Total RNA was extracted from human umbilical vein endothelial cells(HUVEC),and cDNA of extracellular domains 1―4 was amplified and recombined with pQE40 vector.After being expressed,affinity purified,renatured and analyzed by Western blot,the sKDR was assayed for its effects on endothelial cells by [3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide](MTT),and on angiogenesis by chick chorioallantoic membrane(CAM) experiment.sKDR cDNA of 1150 bp was obtained via real-time polymerase chain reaction(RT-PCR),and sKDR was expressed by pQE40 procaryotic expression system,purified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) analysis with only one band and proved by Western blot.MTT assay demonstrateds that sKDR could inhibit the VEGF-stimulated HUVEC from proliferation,and CAM experiment showed sKDR could block the VEGF-induced angiogenesis.sKDR has the biological activity to bind with VEGF ligands and is a potential target for tumor anti-angiogenesis therapy.展开更多
A new selenium source, Nano red elemental selenium (Nano-Se) was used to study the effect on the GPx activity of broiler chick kidney cells (BCKC) in vitro, Sodium selenite (Na_ 2 SeO_ 3 ) and seleno-1-methionine (S...A new selenium source, Nano red elemental selenium (Nano-Se) was used to study the effect on the GPx activity of broiler chick kidney cells (BCKC) in vitro, Sodium selenite (Na_ 2 SeO_ 3 ) and seleno-1-methionine (Se-Met) were used as the controls. The results showed that the effects of three kinds of Se forms on the GPx activity of BCKC were accordant(p>0.05) compared with each other at 0.01,0.05 and 0.10 μmol/L Se concentrations treatments. In the range of 0.00-0.10 μmol/L Se concentrations, the GPx activity increased with elevation of Se concentrations in medium. For the three kinds of Se forms, the GPx activity reached the climax at 0.10 μmol/L Se concentration. At 0.20 and 0.30 μmol/L Se concentrations, the influnces of three kinds of Se forms were not accordant with one another. For Nano-Se, the GPx activity at 0.20 and 0.30 μmol/L Se concentrations remained the same as that at 0.10 μmol/L Se concentration treatment. For Se-Met, the GPx activity at 0.20 μmol/L Se concentration treatment remained the same with 0.10 μmol/L treatment; the GPx activity at 0.30 μmol/L Se concentration treatment was declined significantly(p<0.05) compared with 0.10 or 0.20 μmol/L treatment. For Na_ 2 SeO_ 3 , the GPx activity falled gradually with Se concentration increasing from 0.10 μmol/L to 0.30 μmol/L, and at 0.30 μmol/L Se concentration treatment, the GPx activity was less than the original of BCKC. The results implicated, on the GPx activity of BCKC in vitro, the ranking of width range of the most suitable Se concentration for nutrition curve of the three Se formes is Nano-Se>Se-Met>Na_ 2 SeO_ 3 .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
基金Nacional de Promoción Científica y Tecnológica(Grant:PICTO 2010-0111)the Instituto Antártico Argentino-Dirección Nacional del Antártico(PINST-05)provided financial and logistical support.
文摘In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point.
文摘The exchange of oxygen (O2) and carbon dioxide (CO2) within an incubator has a significant impact on embryonic development (ED) and hatching processes. This study examines the influence of non-ventilation (NV) conditions during the first ten days of incubation at high altitudes on Leghorn hens hatching eggs. Five hundred four hatching eggs were equally divided into three treatment groups and placed in twelve incubators (R = 4). The first group was subjected to standard ventilated conditions (V) during the setting phase. The ventilation inlet holes of the remaining incubators in the NV treatments were closed with either micropore (M) or polypropylene (P) tape, referred to as NVM and NVP groups, respectively. These two different airtight settings were intended to allow for a gradual rise in CO2 naturally generated by the embryos. Results indicate that carbon dioxide concentration gradually increased during the first half of incubation, reaching 1.42% in the NVM group and 1.20% in the NVP group, while the V condition group remained at 0.15%. From 10 days of incubation onwards, normal V conditions were restored in all incubators. The highest hatchability of fertile eggs (HFE) was shown by the NVP group (55.7%), followed by the V (52.6%) and NVM (38.6%) groups. The NVP group showed a greater yolk-free body mass (YFBM) from 10 days of incubation until the hatch basket transfer. NV conditions during the first 10 days of incubation at high altitude produced higher YFBM with gradually decreasing yolk sac mass. In comparison to the NVM and V conditions, the particular NVP condition showed a beneficial impact on the quality of hatched chicks. Sustaining NVP condition (1.2% of CO2) throughout the first half of incubation at high altitude generated the optimal environment in the incubator ensuring the best hatchability results. This study highlights how important it is for hatchery managers to recognize the influence of low O2 and high levels of CO2 on the development trajectories of Leghorn embryos during early incubation at high altitudes.
基金Supported by National Natural Science Foundation of China (30972152)Specialized Research Fund for the Doctoral Program of Higher Education of China (200805040023)~~
文摘[Objective] This study aimed to investigate the distribution law of different goblet cells in the intestinal tracts of African ostrich chicks. [Method] Alcian blue/pe- riodic acid-schiff reaction (AB/PAS) was adopted to observe and analyze the types and distribution of goblet cells in the intestinal tracts of ostrich chicks. Acid mu- copolysaccharide could be stained blue with alcian blue (AB), and neutral mu- copolysaccharide could be stained red with periodic acid-schiff reagent (PAS). [Result] According to AB/PAS results, goblet cells in the intestinal tracts were divided in- to four types: TypeⅠ was pure red, with AB negative result and PAS positive result containing neutral mucoitin; type Ⅱ was pure blue, with AB positive result and PAS negative result containing acidic mucoitin; type Ⅲ was purple reddish, with PAS posi- tive result greater than AB; typeⅣ was purple blue, with AB positive result greater than PAS. Large quantities of goblet cells were found in the intestinal tracts of os- trich chicks, mostly type III and IV.The quantities of goblet cells were decreased gradually in the duodenum, jejunum and ileum, while the quantities were increased in the cecum, colon and rectum. The goblet cells in the large intestine are more than that in the small intestine. The most quantities of goblet cells were contained in rectum. [Conclusion] These results indicate that the distribution of goblet cells is closely related with the structure and function of intestinal tracts. The mucus secret- ed by the goblet Cells plays a series of important roles in the digestion and mucosal immunization.
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Supported by Specialized Research Fund for The Doctoral Program of Huazhong Agricultural University(200805040023)Natural Science Foundation of China(NSFC)(30471249,30972152)~~
文摘[Objective] This study aimed to investigate the differences in morphological structure of tibias between sick and normal ostrich chicks. [Method] Normal and sick ostrich chicks aged 90 days were used in this research for bone mineral density determination, bone demineralization paraffin section preparation (HE staining), bone abrasive disc preparation and scanning electron microscopy (SEM) observation, to analyze the differences in microstructure and ultrastructure of tibias between sick ostrich chicks and normal ones. [Result] Bone mineral density of ostrich chicks suffering from leg disease was much lower than that of the normal ones. Compared with normal tibias, less trabeculae were observed in sick tibias, which were attenuated and began to disappear. In addition, trabeculae micro-fracture could be observed under scanning electron microscope; resorption pits on bone slices formed by osteoclast could be observed under scanning electronic microscope. [Conclusion] These results indicate that the sick tibias all have lower bone density and trabeculae microfracture phenomenon in tibias with different diseases, which might be resulted from osteoporosis.
基金supported by the Shandong Longlive Bio-Technology Co. Ltd., Chinathe Agricultural Science and Technology Innovation Program, China (ASTIP-IAS08)+1 种基金the Special Fund for Agro-Scientific Research in the Public Interest, China (201403047)the China Agriculture Research System (CARS-42)
文摘An experiment was conducted to investigate the effect of dietary supplementation of xylo-oligosaccharides(XOS) on growth performance, meat quality, immune functions, duodenal morphology and intestinal microbial populations of broilers fed a conventional corn-soybean meal basal diet. A total of 450 1-day-old commercial Arbor Acres male broiler chicks were randomly allocated by bodyweight to 1 of 5 treatments with 6 replicate cages(15 broilers per cage) for each of 5 treatments in a completely randomized design. Chicks were fed the basal corn-soybean meal diets supplemented with 0, 25, 50, 75, or 100 mg of XOS kg–1 of diet, respectively, for an experimental duration of 42 days. The results showed that supplementation of XOS affected feed conversion rate(feed/gain, F/G) during days 22–42 and 1–42(P〈0.03), drip loss in thigh muscle(P=0.02), and duodenal crypt depth(P=0.005) on day 42, but had no effect(P〉0.05) on all other measured indices. The chicks fed the diet supplemented with 100 mg of XOS kg–1 had the lowest(P〈0.05) F/G and drip loss in thigh muscle. The drip loss in thigh muscle decreased linearly(P=0.003) as the supplemented XOS increased. Duodenal crypt depth decreased(P〈0.05) at the supplemental level of 75 mg of XOS kg–1. The results indicate that dietary supplementations of 75 and 100 mg of XOS kg–1 are beneficial to broilers fed a conventional corn-soybean meal diet.
基金This study was supported by National Key R&D Program of China(2017YFD0500500)the earmarked fund for Modern Agro-industry Technology Research System(CARS-40-K12)+1 种基金Beijing Innovation Consortium of Agriculture Research System(BAIC04–2018)the Agricultural Science and Technology Innovation Program(ASTIP)of the Chinese Academy of Agricultural Sciences.
文摘Background:Prenatal nutrition is crucial for embryonic development and neonatal growth,and has the potential to be a main determinant of life-long health.In the present study,we used a layer chick model to investigate the effects of in ovo feeding(IOF)of L-arginine(Arg)on growth,intestinal development,intestinal microbiota and metabolism.The treatments included the non-injected control,saline-injected control,and saline containing 2,6,or 10 mg Arg groups.Results:IOF Arg increased early intestinal index and villus height,and enhanced uptake of residual yolk lipid,contributing to subsequent improvement in the early growth performance of chicks.Prenatal Arg supplementation also increased the early microbialα-diversity,the relative abundance of Lactobacillales and Clostridiales,and decreased the relative abundance of Proteobacteria of cecum in chicks.Furthermore,the shift of cecal microbiota composition and the colonization of potential probiotics were accelerated by IOF of Arg.Simultaneously,metabolomics showed that metabolisms of galactose,taurine-conjugated bile acids and lipids were modulated to direct more energy and nutrients towards rapid growth of intestine at the beginning of post-hatch when embryos received IOF of Arg.Conclusions:Prenatal Arg supplementation showed beneficial effects on the early intestinal development,cecal microbiota and host metabolism of layer chicks,contributing to subsequent improvement in the early growth performance.These findings provide new insight into the role of IOF of Arg in the establishment of the gut microbiota of newly-hatched layer chicks,and can expand our fundamental knowledge about prenatal nutrition,early bacterial colonization and intestinal development in neonate.
基金grants from Medical and Sanitary Research Foundation of Zhejiang Province, (No. 2003A077)Huzhou Natural Science Foundation, (No. 2004SZX07-11)
文摘AIM: To evaluate the effect of antisense oligonucleotide targeting midkine (MK-AS) on angiogenesis in chick chorioallantoic membrane (CAM) and in situ human hepatocellular carcinoma (HCC). METHODS: An in situ human hepatocellular carcinoma (HCC) model and CAM assay were used in this experiment. The effect of MK-AS on angiogenesis was evaluated by cell proliferation assay and hematoxylin- eosin (HE) staining. RESULTS: MK-AS significantly inhibited human umbilical vein endothelial cells (HUVEC) and in situ human HCC growth. At the same time, MK-AS suppressed the angiogenesis both in human hepatocellular carcinoma cell line (HEPG2)-induced CAM and in situ human HCC tissues. CONCLUSION: MK-AS is an effective antiangiogenesis agent in vivo.
基金supported by Grants from the National Basic Research Program of China(No.2011CB504300)the Program for New Century Excellent Talents in University(No.NCET-12-0654)the Department of Education of the Guangxi Zhuang Autonomous Region(No.201203YB051)
文摘Background:Cytochrome b5 reductase 2(CYB5R2) is a potential tumor suppressor that inhibits cell proliferation and motility in nasopharyngeal carcinoma(NPC).Inactivation of CYB5R2 is associated with lymph node metastasis in NPC.This study aimed to explore the mechanisms contributing to the anti-neoplastic effects of CYB5R2.Methods:Polymerase chain reaction(PCR) assays were used to analyze the transcription of 84 genes known to be involved in representative cancer pathways in the NPC cell line HONE1.NPC cell lines CNE2 and HONE1 were transiently transfected with CYB5R2,and data was validated by real-time PCR.A chick chorioallantoic membrane(CAM)embryo model was implanted with CYB5R2-expressing CNE2 and HONE1 cells to evaluate the effect of CYB5R2 on angiogenesis.An immunohistochemical assay of the CAM model was used to analyze the protein expression of vascular endothelial growth factor(VEGF).Results:In CYB5R2-transfected NPC cells,PCR assays revealed up-regulated mRNA levels of Fas cell surface death receptor(FAS),FBJ murine osteosarcoma viral oncogene homolog(FOS),phosphoinositide-3-kinase regulatory subunit 1(PIK3R1),integrin beta 3(ITGB3),metastasis suppressor 1(MTSSl),interferon beta 1(IFNB1),and cyclin-dependent kinase inhibitor 2A(CDKN2A) and down-regulated levels of integrin beta 5(ITGB5),insulin-like growth factor 1(IGF1),TEK tyrosine kinase(TEK),transforming growth factor beta receptor 1(TGFBRl),and VEGF.The angiogenesis in the CAM model implanted with CYB5R2-transfected NPC cells was inhibited.Down-regulation of VEGF by CYB5R2 in NPC cells was confirmed by immunohistochemical staining in the CAM model.Conclusion:CYB5R2 up-regulates the expression of genes that negatively modulate angiogenesis in NPC cells and down-regulates the expression of VEGF to reduce angiogenesis,thereby suppressing tumor formation.
基金Supported by the Eskisehir Osmangazi University Scientific Research Project(No.2011/11034)Commission
文摘AIM: To investigate the role of vasoactive intestinal peptide(VIP) in form-deprivation myopia(FDM).METHODS: FDM was created in three groups of eight chicks by placing a translucent diffuser on their right eyes.Intravitreal injections of saline and VIP were applied once a day into the occluded eyes of groups 2 and 3,respectively.Retinoscopy and axial length(AL) measurements were performed on the first and 8^th days of diffuser wear.The retina mR NA levels of the VIP receptors and the ZENK protein in right eyes of the three groups and left eyes of the first group on day 8 were determined using real time polymerase chain reaction(PCR).RESULTS: The median final refraction(D) in right eyes were-13.75(-16.00,-12.00),-11.50(-12.50,-7.50),and-1.50(-4.75,-0.75) in groups 1,2,and 3,respectively(P〈0.001).The median AL(mm) in right eyes were 10.65(10.00,11.10),9.90(9.70,10.00),and 9.20(9.15,9.25) in groups 1,2,and 3,respectively(P〈0.001).The median delta-delta cycle threshold(CT) values for the VIP2 receptors were 1.07(0.82,1.43),1.22(0.98,1.65),0.29(0.22,0.45) in right eyes of groups 1,2,and 3,and 1.18(0.90,1.37) in left eyes of group 1,respectively(P=0.001).The median delta-delta CT values for the ZENK protein were 1.07(0.63,5.03),3.55(2.20,5.55),undetectable in right eyes of groups 1,2,and 3 and 1.89(0.21,4.73) in left eyes of group 1,respectively(P=0.001).CONCLUSION: VIP has potential inhibitory effects in the development of FDM.
文摘A study was under taken to investigate the effect of dietary supplementations of humic acid and esterified glucomannan) on broiler performance and the morphological measurements of small intestine. Two hundred and ten day old broiler chicks were weighed and randomly assigned to seven treatment groups in triplicate. The dietary treatments included T1) control (basal diet without any additives), T2) basal diets supplemented with 0.1% humic acid, T3) basal diets supplemented with 0.2% humic acid, T4) basal diets supplemented with 0.3% humic acid, T5) basal diets supplemented with 0.1% esterified glucomannan, T6) basal diets supplemented with 0.2% esterified glucomannan and T7) basal diets supplemented with 0.3% esterified glucomannan. Different parameters including body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and morphology of small intestine were evaluated during six weeks of experimental period. According to the results, at the end of experimental period, the highest average BWG were recorded in T4 group (fed with 0.3% humic acid), compared to control (T1) and other experimental groups (p < 0.05). Where as, the highest body weight gain were observed during starter period in treatment 7 (fed with 0.3% esterified glucomannan) as compare to other experimental groups (p < 0.05). Statistically, feed intake remained unaffected during the experimental period in all the treatment groups. However, the lowest and the highest feed intake were observed numerically within treatments T4 and T1 with 4229.70 g and 4362.30 g, respectively. Addition of dietary supplements used in the study appeared to have significant effect on the morphology of the small intestine (jejunum mucosal development) of the broilers in different treatment groups. Compared to control group, the inclusion of either humic acid or esterified glucomannon decreased (p < 0.01) the crypt depth and increased villus height respectively (p < 0.05). More ever, the diet supplements with humic acid 0.3% (T4) decreased crypt depth compared to esterified glucomannan and control. The dietary supplementations resulted in an increase in the villus height of intestinal mucosa of broilers. The increase in the villus height was associated with improvement of growth performance for both humic acid and esterified glucomannan. Based on our results it appeared that humic acid and esterified glucomannan can be used as a growth promoter in broiler diets and they can improve the gut health too.
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.
文摘Vascular endothelial growth factors(VEGFs) respectively bind to each of three receptor tyrosine kinases(RTKs),known as Flt-1,KDR and Flt-4.Since VEGFs and their respective families of receptor tyrosine kinases(VEGFRs) are critical proteins which can regulate vascular development during angiogenesis,we decided to explore the inhibitory effects of soluble kinase insert domain-containing receptor(sKDR) on endothelial cells and angiogenesis.Total RNA was extracted from human umbilical vein endothelial cells(HUVEC),and cDNA of extracellular domains 1―4 was amplified and recombined with pQE40 vector.After being expressed,affinity purified,renatured and analyzed by Western blot,the sKDR was assayed for its effects on endothelial cells by [3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide](MTT),and on angiogenesis by chick chorioallantoic membrane(CAM) experiment.sKDR cDNA of 1150 bp was obtained via real-time polymerase chain reaction(RT-PCR),and sKDR was expressed by pQE40 procaryotic expression system,purified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) analysis with only one band and proved by Western blot.MTT assay demonstrateds that sKDR could inhibit the VEGF-stimulated HUVEC from proliferation,and CAM experiment showed sKDR could block the VEGF-induced angiogenesis.sKDR has the biological activity to bind with VEGF ligands and is a potential target for tumor anti-angiogenesis therapy.
文摘A new selenium source, Nano red elemental selenium (Nano-Se) was used to study the effect on the GPx activity of broiler chick kidney cells (BCKC) in vitro, Sodium selenite (Na_ 2 SeO_ 3 ) and seleno-1-methionine (Se-Met) were used as the controls. The results showed that the effects of three kinds of Se forms on the GPx activity of BCKC were accordant(p>0.05) compared with each other at 0.01,0.05 and 0.10 μmol/L Se concentrations treatments. In the range of 0.00-0.10 μmol/L Se concentrations, the GPx activity increased with elevation of Se concentrations in medium. For the three kinds of Se forms, the GPx activity reached the climax at 0.10 μmol/L Se concentration. At 0.20 and 0.30 μmol/L Se concentrations, the influnces of three kinds of Se forms were not accordant with one another. For Nano-Se, the GPx activity at 0.20 and 0.30 μmol/L Se concentrations remained the same as that at 0.10 μmol/L Se concentration treatment. For Se-Met, the GPx activity at 0.20 μmol/L Se concentration treatment remained the same with 0.10 μmol/L treatment; the GPx activity at 0.30 μmol/L Se concentration treatment was declined significantly(p<0.05) compared with 0.10 or 0.20 μmol/L treatment. For Na_ 2 SeO_ 3 , the GPx activity falled gradually with Se concentration increasing from 0.10 μmol/L to 0.30 μmol/L, and at 0.30 μmol/L Se concentration treatment, the GPx activity was less than the original of BCKC. The results implicated, on the GPx activity of BCKC in vitro, the ranking of width range of the most suitable Se concentration for nutrition curve of the three Se formes is Nano-Se>Se-Met>Na_ 2 SeO_ 3 .
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.