In vivo chondrogenesis of adult bone-marrow-derived autologous mesenchymal stem cells

The purpose of this study has been to investigate the possible effects of the normal joint cavity environment on chondrocytic differentiation of bone-marrow-derived mesenchymal stem cells (MSCs). Autologous bone marrow was aspirated from the iliac crest of male sheep. MSCs were purified, expanded, and labeled with the fluorescent dye PKH26. Labeled MSCs were then grown on a three-dimensional porous scaffold of poly (L-lactic-co-glycolic acid) in vitro and implanted into the joint cavity by a surgical procedure. At 4 or 8 weeks after implantation, the implants were removed for histochemical and immunohistochemical analysis. The cells labeled with red fluorescent PKH26 in the implants expressed type II collagen and synthesized sulfated proteoglycans. However, the osteoblast-specific marker, osteocalcin, was not detected by immunohistochemistry indicating that the implanted MSCs had not differentiated into osteoblasts by being directly exposed to the normal joint cavity. To investigate the possible factors involved in chondrocytic differentiation of MSCs further, we co-cultured sheep MSCs with the main components of the normal joint cavity, viz., synovial fluid or synovial cells, in vitro. After 1 or 2 weeks of co-culture, the MSCs in both co-culture systems expressed markers of chondrogenesis. These results suggest that synovial fluid and synovium from normal joint cavity are important for the chondrocytic differentiation of adult bone-marrow-derived MSCs.This work was supported by the National Natural Science Foundation of China (nos. 39900036, 20174006, and 20221402), the National Advanced Technology Programs of China (nos. 2003AA744051, 2003AA205041), the Award Foundation for Young Teachers from the Ministry of Education, 973 project (no. G1999054306-03), and the 248 key innovative project of Beijing (no. H010210190123).     

Effects of Nickel Chloride on the Erythrocytes and Erythrocyte Immune Adherence Function in Broilers

This study was conducted to investigate the immune adherence function of erythrocytes and erythrocyte induced by dietary nickel chloride (NiCl₂) in broilers fed on a control diet and three experimental diets supplemented with 300, 600, and 900 mg/kg NiCl₂ for 42 days. Blood samples were collected from five broilers in each group at 14, 28, and 42 days of age. Changes of erythrocyte parameters showed that total erythrocyte count (TEC), hemoglobin (Hb) contents, and packed cell volume (PCV) were significantly lower (p?p?p?p?+/K⁺-ATPase) and calcium adenosine triphosphatase (Ca²⁺-ATPase) activities were significantly decreased (p?p?2-treated groups. The results of erythrocyte immune adherence function indicated that erythrocyte C_3b receptor rosette rate (E-C_3bRR) was significantly decreased (p?p?p?p?2 in excess of 300 mg/kg caused anemia and impaired the erythrocytic integrity, erythrocytic ability to transport oxygen, and erythrocyte immune adherence function in broilers. Impairment of the erythrocytes and erythrocyte immune adherence function was one of main effect mechanisms of NiCl₂ on the blood function.     

黄菖蒲叶片对水分的生物学响应及其净化水质作用

为解决漓江流域水质下降和生态系统退化的关键问题,开展黄菖蒲抗逆性以及水质净化作用研究,为漓江水陆交错带生态修复的植物选择提供科学依据。采用盆栽试验,研究了黄菖蒲在不同基质内不同淹水胁迫下的叶片生长情况,共设5个处理,并在全土基质中开展净化水质实验。结果表明:随着水淹深度的增加,黄菖蒲叶片数明显下降;半淹处理对黄菖蒲生长最有利;水淹时间对黄菖蒲叶片数、叶长、叶宽与叶面积有极显著影响;黄菖蒲叶片长度、宽度和叶片数随淹水处理没有明显差异,基质对黄菖蒲的生长无显著差异;水分比基质对黄菖蒲生长影响大;种植黄菖蒲处理后pH减小为中性,在一定程度上可以净化水质,但对氮磷的净化效果不明显。     

Ultra‐sensitive immunoassay biosensors using hybrid plasmonic‐biosilica nanostructured materials

We experimentally demonstrate an ultra‐sensitive immunoassay biosensor using diatom biosilica with self‐assembled plasmonic nanoparticles. As the nature‐created photonic crystal structures, diatoms have been adopted to enhance surface plasmon resonances of metal nanoparticles on the surfaces of diatom frustules and to increase the sensitivity of surface‐enhanced Raman scattering (SERS). In this study, a sandwich SERS immunoassay is developed based on the hybrid plasmonic‐biosilica nanostructured materials that are functionalized with goat anti‐mouse IgG. Our experimental results show that diatom frustules improve the detection limit of mouse IgG to 10 pg/mL, which is ?100× better than conventional colloidal SERS sensors on flat glass.

Ultra‐sensitive immunoassay biosensor using diatom biosilica with self‐assembled plasmonic nanoparticles.     

低钙透析液联合醋酸钙对血液透析患者高磷血症的影响

目的：研究低钙透析液联合醋酸钙治疗对血液透析患者血磷、血钙及甲状旁腺激素iPTH水平的影响。方法：将30例维持性血液透析患者随机分为试验组和对照组,在试验期间所有患者均低磷饮食,两组透析液钙浓度均为1．25mmol／L,试验组同时给予醋酸钙治疗,对照组不应用醋酸钙治疗,三个月后观察和比较两组患者的血钙、血磷及血iPTH水平的变化。结果：治疗前,两组各组血磷、血钙、血磷和血iPTH的水平比较差异均无统计学意义（P〉0．05）。治疗后,对照组血钙水平明显下降（P〈0．05）,血iPTH水平略上升但无统计学意义（P〉0．05）,血磷水平无显著变化（P〉0．05）;试验组血iPTH水平略下降（P〉0．05）,血钙水平无明显变化（P〉0．05）,但血磷明显下降（P〈0．05）;且试验组血磷水平较对照组明显下降（P〈0．05）,血钙水平显著高于对照组（P〈O．05）,但在正常范围内,两组血iPTH水平比较无统计学意义（P〉0．05）。结论：低钙透析液联合醋酸钙治疗可有效降低血液透析患者的血磷水平,且不会导致高钙血症的发生。     

微流控芯片电泳及其法医学应用

在光学性能良好的Brofloat玻璃电泳芯片上,利用自行搭建的共聚焦激光诱导荧光检测系统,通过对芯片管道表面修饰、筛分介质、分离电场强度、进样方式、电泳温度、进样时间等条件的优化,对含15个STR基因座的法医DNA样品进行电泳分离测试实验.通过对芯片电泳条件优化获得了本电泳系统的最佳条件,成功实现8 min内完成DNA样品片段的分离,表明该微流控芯片电泳系统在法医DNA快速分析方面具有良好的应用前景.     

Bioaugmentation accelerates the shift of bacterial community structure against shock load: a case study of coking wastewater treatment by zeolite-sequencing batch reactor

Bioaugmentation with degrading bacteria is an effective method to improve the treatment of refractory industrial wastewater; nevertheless there were controversial opinions about the fate of inoculated bacteria and microbial community dynamics. In this study, two lab-scale sequencing batch reactors filled with modified zeolite were used to treat a coking wastewater with pyridine and quinoline shock load, and a bacterial consortium containing three degrading strains was added in one reactor for bioaugmentation. During 120-day operation, the bioaugmented reactor removed over 99 % pyridine, 99 % quinoline, 85 % TOC, 65 % COD, and 95 % NO₃ ^?-N with higher resistance to the shock load than the non-bioaugmented reactor. Based on the terminal restriction fragment length polymorphism of 16S rDNA, bacterial community diversity increased in the bioaugmented reactor. Principal component analysis revealed that, to cope with the shock load, the indigenous bacterial community recovered to the initial structure by acclimatizing itself constantly to the inhospitable environment; but bioaugmentation accelerated the shift of whole bacterial community, resulting in a far different structure from the initial one. Canonical correspondence analysis indicated that the environmental parameters of pyridine, quinoline, TOC, and NO₃ ^?-N had close negative correlations with bioaugmentation; and NH₃-N and COD were the main parameters to impact on the bacterial community changes and treatment efficiency.