鸡铝氟联合作用--铁与骨矿化和矿物元素的关系

为探讨铝氟联合作用时铁与矿物代谢的关系,在鸡铝氟病及铝危害模型基础上对全血铁和骨铁用 AAS法进行了检测.结果表明,性成熟前各实验组全血铁均升高,但以加氟组更为明显;性成熟后饲料加入氟化物的 3个组全血铁仍高于对照,未加的另3个组则低于或接近对照组.骨铁含量均有所下降.饲氟、骨氟、骨铝与全血铁有明显正相关(P＜0.2)或显著正相关(P＜0.05),与骨铁有明显负相关,差异均有显著或非常明显(P＜0.1) 意义.全血铁与全血钙、镁、磷,骨灰化率、骨矿含量、平均骨壁厚度、骨矿沉积率均呈显著正相关.骨铁与骨钙、镁呈显著或明显负相关,与成骨细胞指数、破骨细胞指数、类骨质体积呈明显或非常显著(P＜0.01)负相关,与骨单位吸收周期呈明显正相关.全血铁与骨铁呈明显负相关.提示,全血与骨骼铁代谢是能分离又相对应的体系,可能有相互平衡、调节和补偿作用.铁不仅是血红蛋白的必需成分,还与骨矿化和骨细胞及矿物元素有密切关系.     

新型稀土镁合金螺钉体内促骨修复及体外生物相容性研究

为测试新型稀土镁合金的生物相容性及降解产物致敏性; 评价新型稀土镁合金螺钉对骨伤模型的治疗效果, 基于NZ30K镁合金添加Mn元素制成新型稀土镁合金, 并通过后期加工制成不同规格的螺钉. 将稀土镁合金螺钉浸入磷酸盐缓冲液中制作浸提液, 于大鼠后肢背部皮下注射, 观察浸提液皮下致敏性. 将螺钉打磨制成圆片植入到大鼠皮下, 观察皮下降解产气情况, 以可吸收骨蜡作为对照同位置皮下植入. 建立兔骨损伤模型, 将稀土镁合金植入, 定期拍摄X光检查螺钉降解情况, 按照时间顺序分别于8周、12周、16周处死实验兔制作肝肾切片、骨切片, 评价肝肾毒性及体内降解情况; 同期以ZA75镁合金为基础添加0.3% Mn元素制成新镁合金, 作为对照组对比稀土镁合金对大鼠骨髓间充质干细胞成骨分化效果. 将浸提液过滤稀释后添加至细胞培养板中, 加入成骨诱导液培养, Westernblot蛋白电泳实验测定骨保护蛋白(OPG)表达情况. 新型稀土镁合金浸提液未表现出致敏性, 皮下降解结果显示植入初中期有气腔产生, 中后期气腔消失, 镁合金完全降解; 组织切片显示, 兔股骨螺钉植入在前中期有一定肝肾毒性, 植入中期促骨生长效果相较于前期更为明显, 植入后期未见明显肝肾毒性, 螺钉降解完全, 植入部位骨质增强; 兔股骨植入降解结果显示植入前期未观察到明显的促进骨生长效果, 螺钉与骨质嵌合紧密, 植入中期促骨生长修复效果呈现, 局部骨组织出现膨隆包裹住螺钉降解产物, 植入后期螺钉完全降解, 植入位置有一小孔未闭合, 股骨近端明显膨隆; 蛋白电泳实验显示, 新型稀土镁合金浸提液可增加OPG表达, 具有良好的生物相容性. 基于NZ30K开发的新型稀土镁合金在动物实验及细胞实验阶段表现出良好的生物相容性, 可为临床应用提供一定参考.     

In vitro blood compatibility and bone mineralization aspects of polymeric scaffold laden with essential oil and metallic particles for bone tissue engineering

Bone tissue engineering scaffolds necessities appropriate physicochemical and mechanical properties to support its renewal. Electrospun scaffolds have been used unequivocally in bone tissue restoration. The main intention of this research is to develop electrospun polyurethane (PU) scaffold decorated with metallic particles and essential oil with advanced properties to make them as a putative candidate. The nanocomposite scaffold exhibited appropriate wettability and suitable fiber diameter compared to the polyurethane scaffold. Interaction of the added constituents with the polyurethane was corroborated through hydrogen bonding formation. Tensile strength of the composites was enhanced compared to the polyurethane scaffold. Thermal analysis depicted the lower weight loss of the composite scaffold than the pristine PU. Blood coagulation was significantly delayed and also the composite surface rendered safe interaction with red blood cells. In vitro toxicity testing using fibroblast cells portrayed the nontoxic behavior of the fabricated material. The above-said advanced properties of the composite scaffold can be warranted for bone tissue engineering application.     

Simple Radical Polymerization of Poly(Alginate‐Graft‐N‐Isopropylacrylamide) Injectable Thermoresponsive Hydrogel with the Potential for Localized and Sustained Delivery of Stem Cells and Bioactive Molecules

In this study, thermoresponsive copolymers that are fully injectable, biocompatible, and biodegradable and are synthesized via graft copolymerization of poly(N‐isopropylacrylamide) onto alginate using a free‐radical reaction are presented. This new synthesis method does not involve multisteps or associated toxicity issues, and has the potential to reduce scale‐up difficulties. Chemical and physical analyses verify the resultant graft copolymer structure. The lower critical solution temperature, which is a characteristic of sol–gel transition, is observed at 32 °C. The degradation properties indicate suitable degradation kinetics for drug delivery and bone tissue engineering applications. The synthesized P(Alg‐g‐NIPAAm) hydrogel is noncytotoxic with both human osteosarcoma (MG63) cells and porcine bone marrow derived mesenchymal stem cells (pBMSCs). pBMSCs encapsulated in the P(Alg‐g‐NIPAAm) hydrogel remain viable, show uniform distribution within the injected hydrogel, and undergo osteogenic and chondrogenic differentiation under appropriate culture conditions. Furthermore, for the first time, this work will explore the influence of alginate viscosity on the viscoelastic properties of the resulting copolymer hydrogels, which influences the rate of medical device formation and subsequent drug release. Together the results of this study indicate that the newly synthesized P(Alg‐g‐NIPAAm) hydrogel has potential to serve as a versatile and improved injectable platform for drug delivery and bone tissue engineering applications.     

On the possibilities of ICP-AES for analysis of archaeological bones

The possibility of using inductively coupled plasma atomic emission spectrometry (ICP-AES) to determine the elemental composition of archaeological bones elements was evaluated and discussed. The interferences of the major elements (Ca, P, K, Na, Al and Fe) on the microelements (Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, Zn) were investigated and the appropriate analytical lines were selected. The role of different nebulizers (cross-flow, Babington and Meinhard) on detection limits were investigated. The applicability of the proposed procedure was demonstrated analyzing IAEA-SRM-H-5 (Animal bone); and authentic bone sample dating back to the 4^th century BC. These results were compared to ETAAS and ICP-MS.     

Recent advancement and development of chitin and chitosan-based nanocomposite for drug delivery: Critical approach to clinical research

This review depicts the exposure of chitin and chitosan base multifunctional nanomaterial composites for promising applications in field of biomedical science structure, synthesis as well as potential application from a colossal angle. We elaborated critically each of the chitin and chitosan base nanomaterial with its potential application toward biomedical science. For different biomedical applications it use in form of hydrogels, microsphere, nanoparticles, aerogels, microsphere and in form of scaffold. Due to this it had been blended with different polymer such as starch, cellulose, alginate, lipid, hyaluronic acid, polyvinyl alcohol and caboxymethyl cellulose. In this review article, a comprehensive overview of combination of chitin and chitosan base nanomaterial with natural as well as synthetic polymers and their biomedical applications in biomedical field involving drug delivery system all the technical scientific issues have been addressed; highlighting the recent advancements.     

Empirical Multicomponent Equilibrium and Film-Pore Model for the Sorption of Copper,Cadmium and Zinc onto Bone Char

The adsorption of three metal ions onto bone char has been studied in both equilibrium and kinetic systems. An empirical Langmuir-type equation has been proposed to correlate the experimental equilibrium data for multicomponent systems. The sorption equilibrium of three metal ions, namely, cadmium (II) ion, zinc (II) ion and copper (II) ion in the three binary and one ternary systems is well correlated by the Langmuir-type equation. For the batch kinetic studies, a multicomponent film-pore diffusion model was developed by incorporating this empirical Langmuir-type equation into a single component film-pore diffusion model and was used to correlate the multicomponent batch kinetic data. The multicomponent film-pore diffusion model shows some deviation from the experimental data for the sorption of cadmium ions in Cd-Cu, Cd-Zn and Cd-Cu-Zn systems. However, overall this model gives a good correlation of the experimental data for three binary and one ternary systems.     

Yukmijihwang-Tang Suppresses Receptor Activator of Nuclear Factor Kappa-B Ligand (RANKL)-Induced Osteoclast Differentiation and Prevents Ovariectomy (OVX)-Mediated Bone Loss

Yukmijihwang-tang (YJ) has been used to treat diabetes mellitus, renal disorders, and cognitive impairment in traditional medicine. This study aimed to evaluate the anti-osteoporotic effect of YJ on ovariectomy (OVX)-induced bone loss in a rat and receptor activator of nuclear factor kappa-B ligand (RANKL)-mediated osteoclast differentiation in bone marrow macrophages (BMMs). YJ reduced the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells (MNCs) in an osteoclast/osteoblast co-culture system by regulating the ratio of RANKL/osteoprotegerin (OPG) by osteoblasts. Overall, YJ reduced TRAP-positive cell formation and TRAP activity and F-actin ring formation. Analysis of the underlying mechanisms indicated that YJ inhibited the activation of the nuclear factor of activated T cell cytoplasmic 1 (NFATc1) and c-Fos, resulting in the suppression of osteoclast differentiation-related genes such as TRAP, ATPase, H+ transporting, lysosomal 38 kDa, V0 subunit d2, osteoclast-associated receptor, osteoclast-stimulatory transmembrane protein, dendritic cell-specific transmembrane protein, matrix metalloproteinase-9, cathepsin K, and calcitonin receptor. YJ also inhibited the nuclear translocation of NFATc1. Additionally, YJ markedly inhibited RANKL-induced phosphorylation of signaling pathways activated in the early stages of osteoclast differentiation including the p38, JNK, ERK, and NF-κB. Consistent with these in vitro results, the YJ-administered group showed considerably attenuated bone loss in the OVX-mediated rat model. These results provide promising evidence for the potential novel therapeutic application of YJ for bone diseases such as osteoporosis.     

The Effects of Polyphenol,Tannic Acid,or Tannic Acid in Combination with Pamidronate on Human Osteoblast Cell Line Metabolism

Background: This study investigates the effect of tannic acid (TA) combined with pamidronate (PAM) on a human osteoblast cell line. Methods: EC₅₀ for TA, PAM, and different combination ratios of TA and PAM (25:75, 50:50, 75:25) were measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The combination index value was utilized to analyze the degree of drug interaction, while trypan blue assay was applied to analyze the cells proliferation effect. The mineralization and detection of bone BSP and Osx genes were determined via histochemical staining and PCR test, respectively. Results: The EC₅₀ of osteoblasts treated with TA and a 75:25 ratio of TA and PAM were more potent with lower EC₅₀ at 0.56 µg/mL and 0.48 µg/mL, respectively. The combination of TA and PAM (75:25) was shown to have synergistic interaction. On Day 7, both TA and PAM groups showed significantly increased proliferation compared with control and combination groups. On Day 7, both the TA and combination-treated groups demonstrated a higher production of calcium deposits than the control and PAM-treated groups. Moreover, on Day 7, the combination-treated group showed a significantly higher expression of BSP and Osx genes than both the TA and PAM groups. Conclusion: Combination treatment of TA and PAM at 75:25 ameliorated the highest enhancement of osteoblast proliferation and mineralization as well as caused a high expression of BSP and Osx genes.     

117mSn-TTHMP的制备及生物性质研究

合成了具有亲骨性的氨基膦酸配体-TTHMP(三乙基四胺六甲撑膦酸),制备了117mSn(Ⅳ)-TTHMP,对配合物的稳定性、亲脂性作了研究,考察了它在大白兔体内显像及小鼠体内的分布。将其生物性质与已有文献报道的117mSn(Ⅳ)-HEDTMP作了比较。结果表明117mSn(Ⅳ)-TTHMP的制备简单,稳定性好,亲水,117mSn(Ⅳ)-TTHMP的靶向摄取率高于前两者,是一种极具潜力的新型放射性药物。