San-Huang chicken is a high-quality breed in China with yellow feather, claw and break. However, the abnormal phenomenon of the yellow shank turning into green shank of San-Huang chicken has been a concern, as it seri...San-Huang chicken is a high-quality breed in China with yellow feather, claw and break. However, the abnormal phenomenon of the yellow shank turning into green shank of San-Huang chicken has been a concern, as it seriously reduces the carcass quality and economic benefit of yellow-feathered broilers. In this study, the cause of this abnormal green skin in shank was systematically investigated. Physiological anatomy revealed that the abnormal skin in shank was primarily due to the deposition of melanin under the dermis. After analyzing multiple potential causes such as heredity(pedigree and genetic markers), environment(water quality monitoring) and feed composition(mycotoxin detection), excessive aflatoxin B1(AFB1) in feed was screened, accompanied with a higher L-dihydroxy-phenylalanine(L-DOPA)(P<0.05) and melanin content(P<0.01). So it was speculated that excessive AFB1 might be the main cause of abnormal green skin in shank. Subsequently, the further results showed that a high concentration of AFB1(>170 μg kg–1)indeed induced the abnormal green skin in shank compared to the normal AFB1 content(<10 μg kg–1), and the mRNA levels of TYR, TYRP1, MITE, MC1R and EDN3 genes related to melanin deposition would significantly up-regulate(P<0.01) and the content and activity of tyrosinase(TyR) significantly increased(P<0.05). At the same time, the content of L-DOPA and melanin deposition also increased significantly(P<0.01), which also confirmed the effect of excessive AFB1 on melanin deposition in skin of shank. Results of additional experiments revealed that the AFB1's negative effect on melanin deposition in skin of shank could last for a longer time. Taken together, the results of this study explained the occurrence and possible mechanisms of the abnormal AFB1-related green skin in shank of chickens. Excessive AFB1 in diets increased the L-DOPA content and melanin abnormal deposition in the chicken shank possibly via promoting TyR content and activity, and the expression of melanin synthesis-related genes. Furthermore, our findings once again raised the alarm of the danger of AFB1 in the broiler production.展开更多
Background:The selection of Marek’s disease(MD)-resistant breeds in Partridge Shank chicken,a popular local chicken breed in Henan Province of China,has practical value.We hypothesized that the two polymorphic sites(...Background:The selection of Marek’s disease(MD)-resistant breeds in Partridge Shank chicken,a popular local chicken breed in Henan Province of China,has practical value.We hypothesized that the two polymorphic sites(rs14527240 located in SMOC1 and GGaluGA156129 located in PTPN3)related to MD resistance in White Leghorn chickens are also applicable to Partridge Shank chickens.Methods:In this experiment,we screened 10 live hens and 2 live roosters with the double GG genotype by genotyping the two sites from 6500 Partridge Shank chickens.Nineteen one-day-old chicks with the double GG genotype were obtained by artificial insemination.Seventy-two one-day-old chickens(19 from the population expansion test and 53 randomly selected from chicken farms)were injected with 2000 plaque-forming units of the Md5 virus strain.After 100 days of infection,all chickens were examined by pathological anatomical examination,histological sectioning,genotyping,and a quantitative polymerase chain reaction of SMOC1 and PTPN3.Results:There was only one site(rs14527240 located in SMOC1)associated with MD in Partridge Shank chickens(p<0.05),but the GG genotype of SMOC1 in Partridge Shank chickens indicated susceptibility to MD.SMOC1 expression in MD-susceptible chickens was also significantly higher than that in MDresistant chickens(p<0.05).Conclusion:Therefore,the MD resistance sites selected from White Leghorn chickens were not completely suitable for Partridge Shank chickens,but they can be used as a reference.This study indicated that SMOC1 plays an important role in screening for MD resistance in poultry.展开更多
目的观察5肽类似物165对老年性痴呆(Alzhei mer disease,AD)模型大鼠学习记忆能力及突触后致密区蛋白95(postsynaptic density95,PSD95)和骨架蛋白Shank1表达的影响。方法将45只大鼠随机分为正常对照组、模型组和5肽类似物165治疗组,模...目的观察5肽类似物165对老年性痴呆(Alzhei mer disease,AD)模型大鼠学习记忆能力及突触后致密区蛋白95(postsynaptic density95,PSD95)和骨架蛋白Shank1表达的影响。方法将45只大鼠随机分为正常对照组、模型组和5肽类似物165治疗组,模型组和治疗组大鼠按体重3mg/kg行双侧侧脑室链脲佐菌素(streptozotocin,STZ)注射,第3天重复注射建立AD模型,对照组以人工脑脊液代替STZ。术后21d治疗组按体重0.34mg/(kg.d)给予APP5肽类似物165灌胃干预,其余两组以蒸馏水代替。3周后应用Morris水迷宫、免疫组织化学和Western blotting方法检测大鼠的学习记忆能力及PSD95和Shank1的表达。结果5肽类似物165治疗组大鼠的平均游泳时间较模型组明显缩短(P<0.01),且海马PSD95和Shank1阳性神经细胞数及PSD95和Shank1蛋白表达较模型组明显增加(P<0.05)。结论5肽类似物165可显著提高大鼠学习记忆能力,增加大鼠海马PSD95和Shank1表达,表明其对突触功能和可塑性具改善作用。展开更多
Forefoot pain is common in high-heeled shoe wearers due to the high pressure caused by the center of body mass moving forward and the increased arch height with heel elevation.Sufficient arch support could reduce the ...Forefoot pain is common in high-heeled shoe wearers due to the high pressure caused by the center of body mass moving forward and the increased arch height with heel elevation.Sufficient arch support could reduce the high pressure over forefoot.However,too much arch support could lead to abnormal foot alignment and pain over midfoot.Little information is reported on the relationship among plantar arch height,shank curve design and plantar pressure.This study aimed at quantifying the plantar arch height changes at different heel heights and investigating the effect of shank curve on plantar pressure distribution.The plantar arch height increased to（7.6±1.3） mm at heel height of 75 mm.The Chinese standard suggests the depth of last should be 8.5 mm for heel height of 75 mm.When a shank curve with higher depth of last（11 mm） was used,the peak pressure over forefoot further decreased in midstance phase,which might ease the forefoot problems,while the peak pressure over midfoot increased but not exceeded the discomfort pressure thresholds.To achieve a more ideal pressure distribution in high-heeled shoes,a higher than expected depth of last would be suggested that would not cause discomfort over midfoot.展开更多
基金funded by the grants from the China Agriculture Research System of MOF and MARA (CARS-41)the Agricultural Science and Technology Innovation Program, China (ASTIP-IAS04)。
文摘San-Huang chicken is a high-quality breed in China with yellow feather, claw and break. However, the abnormal phenomenon of the yellow shank turning into green shank of San-Huang chicken has been a concern, as it seriously reduces the carcass quality and economic benefit of yellow-feathered broilers. In this study, the cause of this abnormal green skin in shank was systematically investigated. Physiological anatomy revealed that the abnormal skin in shank was primarily due to the deposition of melanin under the dermis. After analyzing multiple potential causes such as heredity(pedigree and genetic markers), environment(water quality monitoring) and feed composition(mycotoxin detection), excessive aflatoxin B1(AFB1) in feed was screened, accompanied with a higher L-dihydroxy-phenylalanine(L-DOPA)(P<0.05) and melanin content(P<0.01). So it was speculated that excessive AFB1 might be the main cause of abnormal green skin in shank. Subsequently, the further results showed that a high concentration of AFB1(>170 μg kg–1)indeed induced the abnormal green skin in shank compared to the normal AFB1 content(<10 μg kg–1), and the mRNA levels of TYR, TYRP1, MITE, MC1R and EDN3 genes related to melanin deposition would significantly up-regulate(P<0.01) and the content and activity of tyrosinase(TyR) significantly increased(P<0.05). At the same time, the content of L-DOPA and melanin deposition also increased significantly(P<0.01), which also confirmed the effect of excessive AFB1 on melanin deposition in skin of shank. Results of additional experiments revealed that the AFB1's negative effect on melanin deposition in skin of shank could last for a longer time. Taken together, the results of this study explained the occurrence and possible mechanisms of the abnormal AFB1-related green skin in shank of chickens. Excessive AFB1 in diets increased the L-DOPA content and melanin abnormal deposition in the chicken shank possibly via promoting TyR content and activity, and the expression of melanin synthesis-related genes. Furthermore, our findings once again raised the alarm of the danger of AFB1 in the broiler production.
基金supported by grants from Key Research Project of the Shennong Laboratory(Grant Number SN01-2022-05)the Tackling Key Projects in Science and Technology in Henan Province(Grant Number 162102110039)the Independent Innovation Project of Henan Academy of Agricultural Sciences(Grant Number 2022ZC46).
文摘Background:The selection of Marek’s disease(MD)-resistant breeds in Partridge Shank chicken,a popular local chicken breed in Henan Province of China,has practical value.We hypothesized that the two polymorphic sites(rs14527240 located in SMOC1 and GGaluGA156129 located in PTPN3)related to MD resistance in White Leghorn chickens are also applicable to Partridge Shank chickens.Methods:In this experiment,we screened 10 live hens and 2 live roosters with the double GG genotype by genotyping the two sites from 6500 Partridge Shank chickens.Nineteen one-day-old chicks with the double GG genotype were obtained by artificial insemination.Seventy-two one-day-old chickens(19 from the population expansion test and 53 randomly selected from chicken farms)were injected with 2000 plaque-forming units of the Md5 virus strain.After 100 days of infection,all chickens were examined by pathological anatomical examination,histological sectioning,genotyping,and a quantitative polymerase chain reaction of SMOC1 and PTPN3.Results:There was only one site(rs14527240 located in SMOC1)associated with MD in Partridge Shank chickens(p<0.05),but the GG genotype of SMOC1 in Partridge Shank chickens indicated susceptibility to MD.SMOC1 expression in MD-susceptible chickens was also significantly higher than that in MDresistant chickens(p<0.05).Conclusion:Therefore,the MD resistance sites selected from White Leghorn chickens were not completely suitable for Partridge Shank chickens,but they can be used as a reference.This study indicated that SMOC1 plays an important role in screening for MD resistance in poultry.
文摘目的观察5肽类似物165对老年性痴呆(Alzhei mer disease,AD)模型大鼠学习记忆能力及突触后致密区蛋白95(postsynaptic density95,PSD95)和骨架蛋白Shank1表达的影响。方法将45只大鼠随机分为正常对照组、模型组和5肽类似物165治疗组,模型组和治疗组大鼠按体重3mg/kg行双侧侧脑室链脲佐菌素(streptozotocin,STZ)注射,第3天重复注射建立AD模型,对照组以人工脑脊液代替STZ。术后21d治疗组按体重0.34mg/(kg.d)给予APP5肽类似物165灌胃干预,其余两组以蒸馏水代替。3周后应用Morris水迷宫、免疫组织化学和Western blotting方法检测大鼠的学习记忆能力及PSD95和Shank1的表达。结果5肽类似物165治疗组大鼠的平均游泳时间较模型组明显缩短(P<0.01),且海马PSD95和Shank1阳性神经细胞数及PSD95和Shank1蛋白表达较模型组明显增加(P<0.05)。结论5肽类似物165可显著提高大鼠学习记忆能力,增加大鼠海马PSD95和Shank1表达,表明其对突触功能和可塑性具改善作用。
基金supported by the Research Grant Council of Hong Kong (Project Nos. PolyU5331/07E, PolyU5352/08E)a Research Studentship from the Hong Kong Polytechnic University
文摘Forefoot pain is common in high-heeled shoe wearers due to the high pressure caused by the center of body mass moving forward and the increased arch height with heel elevation.Sufficient arch support could reduce the high pressure over forefoot.However,too much arch support could lead to abnormal foot alignment and pain over midfoot.Little information is reported on the relationship among plantar arch height,shank curve design and plantar pressure.This study aimed at quantifying the plantar arch height changes at different heel heights and investigating the effect of shank curve on plantar pressure distribution.The plantar arch height increased to（7.6±1.3） mm at heel height of 75 mm.The Chinese standard suggests the depth of last should be 8.5 mm for heel height of 75 mm.When a shank curve with higher depth of last（11 mm） was used,the peak pressure over forefoot further decreased in midstance phase,which might ease the forefoot problems,while the peak pressure over midfoot increased but not exceeded the discomfort pressure thresholds.To achieve a more ideal pressure distribution in high-heeled shoes,a higher than expected depth of last would be suggested that would not cause discomfort over midfoot.
