重组人钙网蛋白促雄激素性脱发小鼠毛发再生的作用研究

研究重组人钙网蛋白(recombinant human calreticulin,rh-CRT)促雄激素性脱发(androgenetic alopecia,AGA)小鼠毛发再生的作用。建立AGA小鼠模型,局部应用rh-CRT,研究rh-CRT对毛发再生的影响。通过观察不同时间毛发整体外观和局部外观评估毛发的再生,采用颜色测试仪检测皮肤的黑色素指数,利用皮肤镜观察不同类型毛发直径的变化,扫描电镜检测毛小皮的改变,并进一步通过HE染色研究皮肤和真皮脂肪厚度以及毛囊的数量。结果发现,rh-CRT促进AGA小鼠毛发的再生,增加黑色素指数,并显著提高AGA小鼠粗毛和细毛的直径,修复睾酮组(testosterone,TES)诱导的毛小皮的损伤。从皮肤冠状面观察发现rh-CRT显著促进AGA小鼠毛囊数量的表达,并增加皮肤和真皮脂肪的厚度。这些结果表明rh-CRT可以促进AGA小鼠毛发的再生,在防脱产品中具有重要的应用价值。

A novel mouse model of calcific aortic valve stenosis

Background:Calcific aortic valve stenosis(CAVS)is one of the most challenging heart diseases in clinical with rapidly increasing prevalence.However,study of the mecha-nism and treatment of CAVS is hampered by the lack of suitable,robust and efficient models that develop hemodynamically significant stenosis and typical calcium deposi-tion.Here,we aim to establish a mouse model to mimic the development and features of CAVS.Methods:The model was established via aortic valve wire injury(AVWI)combined with vitamin D subcutaneous injected in wild type C57/BL6 mice.Serial transthoracic echocardiography was applied to evaluate aortic jet peak velocity and mean gradi-ent.Histopathological specimens were collected and examined in respect of valve thickening,calcium deposition,collagen accumulation,osteogenic differentiation and inflammation.Results:Serial transthoracic echocardiography revealed that aortic jet peak velocity and mean gradient increased from 7 days post model establishment in a time depend-ent manner and tended to be stable at 28 days.Compared with the sham group,sim-ple AVWI or the vitamin D group,the hybrid model group showed typical pathological features of CAVS,including hemodynamic alterations,increased aortic valve thicken-ing,calcium deposition,collagen accumulation at 28 days.In addition,osteogenic dif-ferentiation,fibrosis and inflammation,which play critical roles in the development of CAVS,were observed in the hybrid model.Conclusions:We established a novel mouse model of CAVS that could be induced efficiently,robustly and economically,and without genetic intervention.It provides a fast track to explore the underlying mechanisms of CAVS and to identify more effec-tive pharmacological targets.

Mechanical Properties and Stress Strain Relationship Models for Bamboo Scrimber

In order to investigate the basic mechanical properties and stress strain relationship model for bamboo scrimber manufactured based on a new technique,a large quantities of experiments have been carried out.Based on the analysis of the test results,the following conclusions can be drawn.Two main typical failure modes were classified for bamboo scrimber specimens both under tension parallel to grain and tension perpendicular to grain.Brittle failure happened for all tensile tests.The slope values for the elastic stages have bigger discreteness compared with those for the specimens under tensile parallel to grain.The failure modes for bamboo scrimber specimens under compression parallel to grain could be divided into four.Only one main failure mode happened both for the bending specimens and the shear specimens.With the COV values of 28.64 and 25.72 respectively,the values for the strength and elastic modulus under tensile perpendicular to grain have the largest discreteness for bamboo scrimber.From the point of CHV values,the relationship among the mechanical parameters for bamboo scrimber were proposed based on the test results.Compared with other green building materials,bamboo scrimber manufactured based on a new technique has better mechanical performance and could be used in construction area.Three stress strain relationship models which are four-linear model,quadratic function model,and cubic function model were proposed for bamboo scrimber specimens manufactured based on a new technique.The latter two models gives better prediction for stress strain relationship in elastic plastic stage.

Compression Behaviors of Parallel Bamboo Strand Lumber Under Static Loading

In order to investigate the influence of length and compression directions upon behaviour of parallel bamboo strand lumber(PBSL)specimens,240 axial compression tests have been performed.With three similar one different typical failure modes,the mechanical performance for PBSL specimens under compression parallel to grain and perpendicular to grain are different as a whole.From the point of the characteristic values,the compression strength parallel to grain is 2.1 times of the compression strength perpendicular to grain.The elastic modulus for compression parallel to grain is 3.64 times of the compression strength perpendicular to grain.While the compression ratios along two compression directions are equal to each other.The bigger Poisson ratios for one typical side surface is 3.93 times of that for another typical side surface for PBSL specimens under compression perpendicular to grain,and the bigger value is equal to that for PBSL specimens under compression parallel to grain.Length can influence the mechanical properties of the PBSL specimens.The size 50 mm×50 mm×100 mm should be good choice for the standard or code to measure the compression strength.PBSL materials have better ductility under compression parallel to grain than that under compression perpendicular to grain.Stress-strain relationship models were proposed for PBSL specimens under compression parallel to grain and perpendicular to grain,respectively.These proposed models gave a good agreement with the test results.

Bacterial and eukaryotic community interactions might contribute to shrimp culture pond soil ecosystem at different culture stages

Sedimentary bacterial and eukaryotic communities are major components of the aquatic ecosystem.Revealing the linkages between their community structure and interactions is crucial to understand the diversity and functions of aquatic and soil ecosystems.However,how their diversity and assembly contribute to their interactions on time scale is unclear.This study examined sedimentary bacterial and eukaryotic communities in shrimp culture ponds at different culture stages.The most abundant bacteria were Proteobacteria(38.27%),whereas the most abundant eukaryotes were Chytridiomycota(27.48%).Bacterial and eukaryotic diversities were correlated(P<0.05),implying the strong interactions between bacteria and eukaryotes.Results showed that the bacterial and eukaryotic communities became increasingly similar on a local scale along with the shrimp culture.Only the eukaryotic community significantly increased in similarity along with the shrimp culture(P<0.05),suggesting that the sedimentary eukaryotic community structure is sensitive under shrimp culture.Co-occurrence network modeling indicated that positive microbial interactions were dominant.The homogeneous selection was the major driver of community assembly.Bacterial diversity negatively correlated with operational taxonomic units and positive links in networks(P<0.05),whereas eukaryotic diversities positively correlated with positive links in networks(P<0.05).This study broadens our knowledge about sedimentary microbial diversity,community assembly,and interaction patterns on time scale,providing a reference for the sustainable management in aquaculture production.