目的探讨富血小板纤维蛋白(platelet rich fibrin,PRF)形态学超微结构及意义。方法选择10例健康志愿者,抽取静脉血制备PRF,对PRF分别行光学显微镜、扫描电子显微镜(scanning electron microscope,SEM)和透射电子显微镜(transmission ele...目的探讨富血小板纤维蛋白(platelet rich fibrin,PRF)形态学超微结构及意义。方法选择10例健康志愿者,抽取静脉血制备PRF,对PRF分别行光学显微镜、扫描电子显微镜(scanning electron microscope,SEM)和透射电子显微镜(transmission electron microscope,TEM)观察。结果 PRF为淡黄色纤维蛋白凝胶,H-E染色见胶原纤维为染色均一的淡红色网状结构,在近细胞端纤维排列较致密,含大量血小板。吉姆萨染色见淡蓝色的胶原纤维为网状结构,近细胞端见染为蓝色的白细胞。SEM发现胶原纤维排列成疏松多孔网状支架结构,含大量静止或伸出伪足的血小板及白细胞。TEM发现血小板处于静止或激活状态,α-颗粒释放于细胞和纤维之间,在细胞之间见高密度区为血小板释放的颗粒。结论 PRF胶原纤维的网状立体结构和富含血小板激活释放生长因子,对生物学作用发挥有重要意义。展开更多
Since May 2006,a highly pathogenic porcine reproductive and respiratory syndrome virus （HP-PRRSV） variant characterized by 30 amino acids deletion within its NSP2-coding region emerged and caused extensive economic ...Since May 2006,a highly pathogenic porcine reproductive and respiratory syndrome virus （HP-PRRSV） variant characterized by 30 amino acids deletion within its NSP2-coding region emerged and caused extensive economic losses to China＇s pig industry.To investigate the in vivo pathogenicity and immune responses of the newly emerging PRRSV,3 groups of 60-d-old conventional piglets were inoculated intranasally with a representative strain of the HP-PRRSV variant HuN4 with 3 different infection doses （3×103-3×105 TCID50）.The results revealed that the virus variant caused severe disease in piglets and the significant clinical characteristics consisted of persistently high fever （41.0-41.9oC） and high morbidity and mortality （60-100%）,the marked clinical signs of PRRS and severe histopathogenic damages in multiple organs.It induced rapid and intense humoral immune responses and seroconversion was detected in most infected pigs at 7 d post-infection （DPI）.The virus vigorously replicated in vivo and the highest virus average titer was 9.7 log copies mL-1 serum at 7 DPI.Elevated levels of IFN-g and IL-10 cytokine production in serum in this study were also observed.Taken together,our results demonstrated that the HP-PRRSV variant HuN4 strain is highly pathogenic for piglets and suitable to be a reference strain of highly virulent PRRSV for evaluating the efficacy of the new vaccines.展开更多
文摘目的探讨富血小板纤维蛋白(platelet rich fibrin,PRF)形态学超微结构及意义。方法选择10例健康志愿者,抽取静脉血制备PRF,对PRF分别行光学显微镜、扫描电子显微镜(scanning electron microscope,SEM)和透射电子显微镜(transmission electron microscope,TEM)观察。结果 PRF为淡黄色纤维蛋白凝胶,H-E染色见胶原纤维为染色均一的淡红色网状结构,在近细胞端纤维排列较致密,含大量血小板。吉姆萨染色见淡蓝色的胶原纤维为网状结构,近细胞端见染为蓝色的白细胞。SEM发现胶原纤维排列成疏松多孔网状支架结构,含大量静止或伸出伪足的血小板及白细胞。TEM发现血小板处于静止或激活状态,α-颗粒释放于细胞和纤维之间,在细胞之间见高密度区为血小板释放的颗粒。结论 PRF胶原纤维的网状立体结构和富含血小板激活释放生长因子,对生物学作用发挥有重要意义。
基金supported by grants from the National Basic Research Program of China (973 Program,2005CB523200)the National High-Tech Research and Development Program of China (863 Program,2006AA10A20 4)+1 种基金the National Key Technology R&D Program (2006BAD 06A04/18/01/03)the National Natural Science Foundation of China (30470072)
文摘Since May 2006,a highly pathogenic porcine reproductive and respiratory syndrome virus （HP-PRRSV） variant characterized by 30 amino acids deletion within its NSP2-coding region emerged and caused extensive economic losses to China＇s pig industry.To investigate the in vivo pathogenicity and immune responses of the newly emerging PRRSV,3 groups of 60-d-old conventional piglets were inoculated intranasally with a representative strain of the HP-PRRSV variant HuN4 with 3 different infection doses （3×103-3×105 TCID50）.The results revealed that the virus variant caused severe disease in piglets and the significant clinical characteristics consisted of persistently high fever （41.0-41.9oC） and high morbidity and mortality （60-100%）,the marked clinical signs of PRRS and severe histopathogenic damages in multiple organs.It induced rapid and intense humoral immune responses and seroconversion was detected in most infected pigs at 7 d post-infection （DPI）.The virus vigorously replicated in vivo and the highest virus average titer was 9.7 log copies mL-1 serum at 7 DPI.Elevated levels of IFN-g and IL-10 cytokine production in serum in this study were also observed.Taken together,our results demonstrated that the HP-PRRSV variant HuN4 strain is highly pathogenic for piglets and suitable to be a reference strain of highly virulent PRRSV for evaluating the efficacy of the new vaccines.
