槐耳清膏治疗肝癌的实验研究

目的　探讨槐耳清膏对人胎脐静脉内皮细胞的作用 ,以及其对裸鼠皮下接种肝癌细胞形成肝癌的抑制作用及其可能机制。方法　用不同浓度的槐耳清膏作用于人胎脐静脉血管内皮细胞 ,观察其对细胞的增殖能力、迁移能力、附壁能力及血管生成的影响 ,同时观察其对裸鼠皮下接种肝癌细胞形成肝癌过程的影响。结果　槐耳清膏≥ 2mg/ml时可显著降低肿瘤组织的血管内皮细胞增殖能力 ,减少血管形成 ,抑制血管内皮细胞的迁移、黏附 ,从而降低微血管密度。槐耳清膏 ( 3g/kg) MMC( 5 0 0 μg/kg)同时作用于裸鼠的肝癌组织 ,其抑瘤作用最强 ,后依次为MMC组 ,槐耳清膏 ( 3g/kg)组。结论　槐耳清膏对肝癌有抑制作用 ,其可能机制是作用于血管内皮细胞 ,影响血管内皮细胞的增殖能力、迁移能力、附壁能力及血管生成 ,从而抑制肝癌组织的血管生成 ,降低肝癌组织的微血管密度而发挥抑制肝癌生长的作用     

血瘀证兔模型血管内皮细胞中一氧化氮合酶 的基因表达及其分泌一氧化氮的变化

【目的】了解实验性血瘀证动物模型血管内皮细胞中一氧化氮合酶(NOS)的基因表达及其分泌NO的变化。【方法】用半定量RT-PCR方法检测模型组体内血管内皮细胞及体外培养的细胞中组成型一氧化氮合酶mRNA的表达,并相应测定分泌的NO水平。【结果】与对照组比较,模型组兔体内血管内皮细胞中组成型NOS(cNOS)基因表达以及血浆和原代培养液中NO水平皆明显下降(P＜0.01),同期血浆中NO含量与内皮细胞中cNOSmRNA的表达水平呈正相关(r=0.739,P＜0.01)。两组间体外培养的传代细胞中cNOS基因表达及培养液上清中NO含量无明显差异(P＞0.05),但NO水平都比各自原代培养液中的明显升高(P＜0.01,P＜0.05)。【结论】短期内血瘀证兔模型体内内源性NO水平降低主要是cNOS基因表达下降导致的,随时间的延长,不排除诱导型NOS(iNOS)及体内其他因素对分泌NO的综合影响。     

川芎嗪对家兔血管内皮细胞修复的影响

【目的】观察川芎嗪对血管损伤后内皮细胞修复的作用 ,探讨其作用机理与环节 ,为显微血管外科提供新的用药依据。【方法】新西兰大耳白兔 2 4只 ,行右侧股动脉切断后即刻端端吻合造模 ,术后随机分成川芎嗪治疗组、肝素治疗组及空白对照组予处理 ,术后 1、 3、 7、 14d分别切取大白兔吻合段动脉 ,作电镜扫描检测 ,观察内皮细胞的生长情况并作组间比较。【结果】在促进血管吻合术后血管内皮细胞的修复 ,促进血流通畅方面川芎嗪组与肝素组相当 (P >0 .0 5) ,两者均优于空白组 (P <0 .0 5)。【结论】川芎嗪能促进血管损伤后内皮细胞的修复 ,在显微血管外科具有肯定的使用价值。     

Bone From Blood: Characteristics and Clinical Implications of Circulating Osteogenic Progenitor (COP) Cells

Circulating osteogenic progenitor (COP) cells are a population of cells in the peripheral blood with the capacity for bone formation, as well as broader differentiation into mesoderm-like cells in vitro. Although some of their biological characteristics are documented in vitro, their role in diseases of the musculoskeletal system remains yet to be fully evaluated. In this review, we provide an overview of the role of COP cells in a number of physiological and pathological conditions, as well as identify areas for future research. In addition, we suggest possible areas for clinical utilization in the management of musculoskeletal diseases. © 2020 American Society for Bone and Mineral Research (ASBMR).     

针刺治疗老年性血管性痴呆的疗效观察

采用四神针、智三针、水沟为主穴配神门、后溪、足三里、太溪，电针与手法结合治疗血管性痴呆３０例，同时设口服西药阿尼西坦对照组３０例相比较。结果针刺组总有效率８６．７％，对照组总有效率６３．３％，针刺组疗效明显优于对照组（Ｐ＜０．０５）。     

Patterning Collagen/Poloxamine-Methacrylate Hydrogels for Tissue-Engineering-Inspired Microfluidic and Laser Lithography Applications

The ability to pattern semi-synthetic collagen/poloxamine-methacrylate hydrogels into straight-channel flow circuits and sub-millimeter-sized rectangular blocks for tissue-engineering applications was evaluated. Endothelial cells, grown on the surface of flat collagen/poloxamine-methacrylate hydrogels, proliferated, expressed ICAM-1 (but not VCAM-1) and began to detach after 6 days. Seeding endothelial cells onto the lumen surface of straight collagen/poloxamine-methacrylate flow channels increased ICAM-1 and VCAM-1 expression, and exposure to laminar shear stress (0.3–10 dyn/cm²) was unable to attenuate activation on the relatively few cells that were able to withstand flow associated ablation. The enrichment of poloxamine-methacrylate at the lumen surface during fabrication likely caused the decrease in cell attachment and increased activation. To micropattern more complex structures, confocal microscopy UV laser lithography was used to selectively cross-link a HepG2-containing pre-polymer solution of collagen/poloxamine-methacrylate. Turbidity (caused by suspended cells and the incomplete miscibility of collagen and poloxamine-methacrylate) scattered the UV laser energy and necessitated the optimization of exposure times with respect to cross-linking extent and cell viability. Free radical diffusion beyond the bounds of the initial photopattern reduced the resolution of the structures and created a weakly cross-linked periphery around the original pattern. Over time, HepG2 cells migrated towards the less cross-linked periphery and proliferated, creating a non-uniform distribution of cells.     

Uptake of Enzymatically-Digested Hyaluronan by Liver Endothelial Cells in Vivo and in Vitro

Intravenously-injected hyaluronan (HA) is distributed into liver in which endothelium is a site of uptake and degradation of HA. The role and fate of HA have been widely investigated; however, effects of size and dose of HA on its metabolism have not been well documented yet. To investigate these effects, we prepared fluorescein-labeled HAs, according to the modified methods described by de Belder and Wik, which were enzymatically digested. The 90 kDa fluorescein-labeled HA gradually accumulated in a liver that was distributed into the endothelium; however, 10 kDa or less HA did not. Cell fractionation and flow cytometry further demonstrated the cell of uptake in the liver is an endothelial cell, both in vivo and in vitro. Interestingly, the largest uptake by liver endothelial cells in vitro was observed in 10 kDa HA, even though which did not accumulate in liver in vivo. These results suggest that the result observed with 10 kDa HA in vivo is due to the rapid excretion in urine. Thus, inhibiting of the digestion or suppressing of the urinary excretion would enhance uptake of HA in vivo. These ideas may help to deliver drugs or genes targeting to liver endothelium.     

Heparin-Conjugated PCL Scaffolds Fabricated by Electrospinning and Loaded with Fibroblast Growth Factor 2

A biodegradable poly(ε-caprolactone) (PCL) was synthesized by ring-opening polymerization of ε-caprolactone catalyzed by Sn(Oct)₂/BDO, followed by the heparin conjugation using EDC/NHS chemistry. The structure of the heparin–PCL conjugate was characterized by ¹H-NMR and GPC. The results of static contact angle and water uptake ratio measurements also confirmed the conjugation of heparin with the polyester. Its in vitro anticoagulation time was substantially extended, as evidenced by activated partial thromboplastin time (APTT) testing. Afterwards the conjugate was electrospun into small-diameter tubular scaffolds and loaded with Fibroblast Growth Factor 2 (FGF2) in aqueous solution. The loading efficiency was assayed by enzyme-linked immunosorbent assay (ELISA); the results indicated that the conjugate holds a higher loading efficiency than the blank polyester. The viability of released FGF2 was evaluated by MTT and cell adhesion tests. The amount and morphology of cells were significantly improved after FGF2 loading onto the electrospun heparin–PCL vascular scaffolds.     

A novel controlled drug-delivery system for growth hormone applied to healing skin wounds in diabetic rats

Controlled release systems for drugs, hormones and growth factors can be particularly useful in tissue repair processes. These systems act as a biodegradable support containing the substance to be delivered, allowing their gradual release. In the past years, the local application of growth factors has acquired special relevance as a therapeutic option for use in subjects who show deficient tissue scarring, the hormone dose being the limiting factor for its success. In this study, the in vitro biocompatibility of a copolymer formed by vinylpyrrolidone and 2-hydroxyethyl methacrylate, used as an administration vehicle for hGH, was evaluated. The system was then tested in vivo in terms of its capacity for healing incisional wounds in healthy and diabetic rats. For the in vitro studies, polymer and hormone degradation rates were determined, and polymer biocompatibility was evaluated in fibroblast cultures. In the in vivo experiments, an incision was made in the back of the animals, and polymers discs with/without hGH, were introduced in the aperture. Morphological, immunohistochemical and morphometric evaluations were performed on wound tissue specimens 3-10 days after surgery. In vitro, the polymer was found to be biodegradable and showed no toxic effects on fibroblasts, the hormone being slowly released to the culture medium. In untreated diabetic rats, a delayed skin scarring and cell response were observed, compared to that noted in healthy animals. Skin closure, keratinisation and fibrosis occurred earlier in the presence of the polymer-hGH system. The use of this co-polymer as an administration vehicle for hGH improves the wound scarring process in the pathological setting of diabetes.     

Bioactive functionalized polymer of malic acid for bone repair and muscle regeneration

A bioactive poly(β-hydroxyalkanoate) derived from malic acid was prepared and tested on bone repair and muscle regeneration. This functionalized and hydrolyzable polymer was obtained after several steps, the first one being the anionic copolymerization of three malolactonic acid esters. Chemical modifications were carried out on the terpolymer to turn benzyl-protecting groups into carboxyl groups and allyl groups into sulfonate groups. The resulting polymer bore carboxylate, sulfonate, and sec-butyl pendent groups in 65/25/10 molar proportions and were aimed at interacting with heparan binding growth factors. This polymer did not present any toxic effect in cell viability of HepG₂ cells, over a large range of concentrations (0.01-0.25 mg l^-1). Its ability to improve wound healing was tested in vivo and positive results are reported. Furthermore, the bioactivity of this polymer was evaluated using the regeneration model of Extensor digitorum longus (EDL) rat muscle. The study displayed a significant increase in the muscle regeneration and maturation.