Evidence of proteins,chromosomes and chemical markers of DNA in exceptionally preserved dinosaur cartilage

A histological ground-section from a duck-billed dinosaur nestling (Hypacrosaurus stebingeri) revealed microstructures morphologically consistent with nuclei and chromosomes in cells within calcified cartilage. We hypothesized that this exceptional cellular preservation extended to the molecular level and had molecular features in common with extant avian cartilage. Histochemical and immunological evidence supports in situ preservation of extracellular matrix components found in extant cartilage, including glycosaminoglycans and collagen type II. Furthermore, isolated Hypacrosaurus chondrocytes react positively with two DNA intercalating stains. Specific DNA staining is only observed inside the isolated cells, suggesting endogenous nuclear material survived fossilization. Our data support the hypothesis that calcified cartilage is preserved at the molecular level in this Mesozoic material, and suggest that remnants of once-living chondrocytes, including their DNA, may preserve for millions of years.     

心肌胶原纤维的作用及对心脏机能的影响

目前运动员的训练负荷是值得注意的问题，其直接影响训练效果。而心脏功能是影响运动员训练负荷的主要方面。心脏功能不仅取决于心肌细胞本身的收缩功能，同时还取决于细胞外基质成分，特别是心肌胶原纤维，其不仅具有支持和连接作用。而且在协调心肌力的传递、信息的传导、营养物质的输送等方面具有重要作用。心肌胶原网络异常。将影响心脏的收缩、舒张功能和正常心肌的电生理，还可能诱导心力衰竭的发生。但目前心肌胶原网络与心肌运动的具体关系还不确切。     

酸-酶结合法提取牛肌腱胶原纤维的研究

以牛肌腱为原料,分别利用酸-酶结合法和酶法从冻干碎块中提取胶原纤维,经过盐析、透析、离心和冷冻干燥后制备得到高纯度胶原纤维.通过测定胶原纤维中羟脯氨酸的含量,得到酸-酶结合法的得率为44.9%,远大于单独用酶提取胶原纤维的得率33.8%.对制备的胶原纤维进行红外扫描和差示量热扫描(DSC),结果表明胶原纤维保持了完整的三股螺旋结构,DSC扫描结果表明冻干胶原纤维的变性温度为60.8℃.     

Derived vascular endothelial cells induced by mucoepidermoid carcinoma cells: 3-dimensional collagen matrix model

Mucoepidermoid carcinoma undergoes uniquely vigorous angiogenic and neovascularization processes, possibly due to proliferation of vascular endothelial cells (ECs) induced by mucoepidermoid carcinoma cells (MCCs) in their three-dimensional (3D) microenvironment. To date, no studies have dealt with tumor cells and vascular ECs from the same origin of mucoepidermoid carcinoma using the in vitro 3D microenvironment model. In this context, the current research aims to observe neovascularization with mucoepidermoid carcinoma microvascular ECs (MCMECs) conditioned by the microenvironment in the 3D collagen matrix model. We observed the growth of MCMECs purified by immunomagnetic beads and induced by MCCs, and characteristics of tubule-like structures (TLSs) formed by induced MCMECs or non-induced MCMECs. The assessment parameters involved the growth curve, the length, the outer and inner diameters, and the wall thickness of the TLSs, and the cell cycle. Results showed that MCCs induced formation of the TLSs in the 3D collagen matrix model. A statistically significant difference was noted regarding the count of TLSs between the control group and the induction group on the 4th day of culture (t=5.00, P=0.001). The outer and inner diameters (t ₁=5.549, P ₁=0.000; t ₂=10.663, P ₂=0.000) and lengths (t=18.035, P=0.000) of the TLSs in the induction group were statistically significant larger than those in the control group. The TLSs were formed at the earlier time in the induction group compared with the control group. It is concluded that MCCs promote growth and migration of MCMECs, and formation of the TLSs. The 3D collagen matrix model with MCMECs induced by MCCs in the current research may be a favorable choice for research on pro-angiogenic factors in progression of mucoepidermoid carcinoma.     

运动性和高血压性心脏肥大心肌间质胶原网络重塑及其对左心室功能的影响

目的:探讨运动性和高血压性心脏肥大大鼠心肌间质胶原网络的重塑及其对左心室功能的影响.方法:采用跑台训练方式和腹主动脉缩窄术分别建立运动性心肌肥大大鼠模型和高血压性心肌肥大大鼠模型.心脏离体灌注测定左心室功能;扫描电镜和透射电镜观察心肌胶原网络重构;通过羟脯氨酸测定心肌胶原的浓度;Western-blot进行Ⅰ型、Ⅲ型胶原分析.结果:高血压大鼠的平均动脉压始终较高(P＜0.05),而训练组大鼠的动脉血压始终较低(P＜0.05);高血压大鼠的心脏舒张速率低于训练组(P＜0.05);高血压性大鼠左心室羟脯氨酸的浓度明显升高(P＜0.05),而训练大鼠左心室羟脯氨酸浓度并没有显著升高;高血压大鼠的左心室Ⅲ型胶原与Ⅰ型胶原的比值下降明显(P＜0.05),而训练组大鼠并没有表现出相同的结果.结论:运动训练可以使大鼠心肌细胞与间质胶原同步增长,心脏功能提高,心肌舒缩性能增强;而慢性高血压性大鼠导致心肌细胞与间质胶原不成比例的增长,间质胶原过度增生,心脏功能受到损伤.心肌间质胶原网络的重塑对大鼠左心室功能具有重要影响.     

中部1/3髌韧带切除后其修复过程中的细胞行为及组织学观察

在大白鼠体内模型中,对实验性切除中部1/3髌韧带后,剩余部分髌韧带早期修复过程中的细胞行为和组织学变化进行了研究。研究表明:髌韧带存在着内在修复能力,在本模型中伤口的修复是从伤口中部开始并向腹侧和背侧延伸。伤口的修复先是伤口周边的细胞移行进伤口,然后到达目的地的细胞开始分泌胶原蛋白,并形成新生的胶原纤维。纤维粘连蛋白在损伤修复的早期存在表达,可能是充当使参与修复的细胞从伤口的边缘移行到伤口中央的生物桥梁。伤口中的细胞和胶原纤维修复到接近组织学正常的时间约需6至9个月。     

Rehabilitation and nutrition protocols for optimising return to play from traditional ACL reconstruction in elite rugby union players: A case study

Current nutrition and exercise focus during rehabilitation periods has been on reducing muscle atrophy associated with immobilisation. This case report outlines a best practice anterior cruciate ligament (ACL) rehabilitation programme undertaken by two professional rugby athletes, with the addition of an evidence-based supplementation (gelatine and vitamin C) and exercise protocol focused on collagenous tissue. Both players ruptured their left ACL and were repaired with a traditional hamstring graft. Players undertook a structured rehabilitation programme for 34 weeks before being clinically assessed ready to play. Players saw minimal changes in body composition in the early rehabilitation period (P1 – 0.8 kg; P2 – 0.4 kg). Leg lean mass reduced in both legs of Player 1 (Injured – 0.8 kg, Non-injured – 0.6 kg) at 17 weeks, with Player 2 only experiencing a loss of 0.3 kg of lean tissue in the injured leg. Both players returned to baseline body compositions after 24 weeks. Leg strength returned to a maximum at 24 and 15 weeks, respectively, with knee function returning to baseline by 30 weeks. This case report provides evidence that nutrition and rehabilitation programmes targeted at minimising the effects of disuse in both muscle and connective tissue may assist return to play after ACL injury.     

力竭大鼠跟腱低功率激光照射前后IGF-Ⅰ及胶原含量的变化

摘要：目的：探讨低功率激光照射对一次性离心力竭运动大鼠跟腱IGF-Ⅰ及胶原含量的影响。方法：一月龄雄性Wistar大鼠随机分为空白组、力竭运动组,力竭运动组又分为1、2、3、7 d激光照射组和对照组。采用透射电镜观察及ELISA法进行测定,动态观察力竭运动后大鼠跟腱修复过程中低功率激光照射前后IGF-I、羟脯氨酸、Collagen-Ⅰ、Collagen-Ⅲ含量的变化。结果：电镜观察激光照射3 d组大鼠跟腱被破坏的胶原纤维排布结构已有所改善;1、2、3 d激光照射组大鼠跟腱IGF-Ⅰ含量均显著高于同一取材时间对照组（P<0.05）,7 d激光照射组显著低于7 d对照组（P<0.05）;Collagen-Ⅰ含量3、7 d激光照射组显著高于同一取材时间对照组（P<0.05）,2 d激光照射组Collagen-Ⅲ含量显著高于2 d对照组（P<0.05）,3、7 d激光照射组Collagen-Ⅲ均显著低于同一取材时间对照组（P<0.05）。结论：低功率激光照射使大鼠跟腱组织中IGF-Ⅰ蛋白的合成量增加,加快腱细胞增殖的速度,减少微损伤修复的时程;同时能够调节腱细胞外基质,加快胶原的代谢,提高微损伤修复的质量。     

浅谈伞套的功能开发与创新设计

伞套是伞产品的重要组成部分。当今设计界对于伞体设计给予了足够的重视,伞体设计呈现出日新月异的面貌。与此同时,伞套设计尚停留在非常初级的阶段,而且由于开发的程度不够,伞套使用功能正在逐渐淡化。本文以产品创新开发的角度,结合当今伞设计的主要设计思路,从功能设计角度分析了伞套设计的可能性和必要性,最后提出了伞套设计创新的思路。     

Optimization of antioxidant activity by response surface methodology in hydrolysates of jellyfish (Rhopilema esculentum) umbrella collagen

To optimize the hydrolysis conditions to prepare hydrolysates of jellyfish umbrella collagen with the highest hydroxyl radical scavenging activity, collagen extracted from jellyfish umbrella was hydrolyzed with trypsin, and response surface methodology (RSM) was applied. The optimum conditions obtained from experiments were pH 7.75, temperature (7) 48.77 ℃, and enzyme-to-substrate ratio ([E]/[S]) 3.50%. The analysis of variance in RSM showed that pH and [E]/[S] were important factors that significantly affected the process (P<0.05 and P<0.01, respectively). The hydrolysates of jellyfish umbrella collagen were fractionated by high performance liquid chromatography (HPLC), and three fractions (HF-1>3000 Da, 1000 Da相似文献