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101.
Bone cancer is a malignant primary tumour of the bone with different typing, such as, osteosarcoma, chondrosarcoma, Ewing’s sarcoma and fibrosarcoma. Despite the clinical efficacy of conventional therapies of bone cancer, most patients eventually relapse and the disease remains incurable. Therefore, new therapeutic strategies are needed to improve patient outcome. In this review article, we have discussed the role of resveratrol in preventing bone and spinal cancers and therapeutics. Resveratrol (3,5,4′-trihydroxy-trans-stilbene) is a natural polyphenol, which has been widely reported as an anticancer molecule. Resveratrol exhibits multiple tumour-suppressing activities in bone cancer by affecting a series of critical events. It has the protective effects against oxidative injury, possesses antiproliferative activity and induces apoptosis in cancer cells. Resveratrol might be a good option for the treatment of different types of bone and spinal cancers. 相似文献
102.
Rui I. Falacho Paulo J. Palma Joana A. Marques Maria H. Figueiredo Francisco Caramelo Isabel Dias Carlos Viegas Fernando Guerra 《Molecules (Basel, Switzerland)》2021,26(5)
Collagenated porcine-derived bone graft materials exhibit osteoconductive properties and the development of different formulations intends to enhance bone regeneration. This study aims to evaluate bone healing in a rabbit cancellous bone defect in response to grafting with different physicochemical forms of heterologous porcine bone. Twenty-six adult male New Zealand White rabbits received two critical size femoral bone defects per animal (n = 52), each randomly assigned to one of the five tested materials (Apatos, Gen-Os, mp3, Putty, and Gel 40). Animals were sacrificed at 15- and 30-days post-surgery. Qualitative and quantitative (new bone, particle and connective tissue percentages) histological analyses were performed. Histomorphometry showed statistically significant differences in all evaluated parameters between mp3 and both Putty and Gel 40 groups, regardless of the timepoint (p < 0.05). Moreover, statistical differences were observed between Apatos and both Putty (p = 0.014) and Gel 40 (p = 0.007) groups, at 30 days, in regard to particle percentage. Within each group, regarding new bone formation, mp3 showed significant differences (p = 0.028) between 15 (40.93 ± 3.49%) and 30 (52.49 ± 11.04%) days. Additionally, intragroup analysis concerning the percentage of particles revealed a significant reduction in particle occupied area from 15 to 30 days in mp3 and Gen-Os groups (p = 0.009). All mp3, Gen-Os and Apatos exhibited promising results in terms of new bone formation, thus presenting suitable alternatives to be used in bone regeneration. 相似文献
103.
Rusin Zhao Ruijia Yang Paul R. Cooper Zohaib Khurshid Amin Shavandi Jithendra Ratnayake 《Molecules (Basel, Switzerland)》2021,26(10)
After tooth loss, bone resorption is irreversible, leaving the area without adequate bone volume for successful implant treatment. Bone grafting is the only solution to reverse dental bone loss and is a well-accepted procedure required in one in every four dental implants. Research and development in materials, design and fabrication technologies have expanded over the years to achieve successful and long-lasting dental implants for tooth substitution. This review will critically present the various dental bone graft and substitute materials that have been used to achieve a successful dental implant. The article also reviews the properties of dental bone grafts and various dental bone substitutes that have been studied or are currently available commercially. The various classifications of bone grafts and substitutes, including natural and synthetic materials, are critically presented, and available commercial products in each category are discussed. Different bone substitute materials, including metals, ceramics, polymers, or their combinations, and their chemical, physical, and biocompatibility properties are explored. Limitations of the available materials are presented, and areas which require further research and development are highlighted. Tissue engineering hybrid constructions with enhanced bone regeneration ability, such as cell-based or growth factor-based bone substitutes, are discussed as an emerging area of development. 相似文献
104.
105.
Experiment on mechanical strength of porous trabecular bone shows power law dependence on the density of the structure. Physical structure and mechanical properties of the trabecular network are modelled here with a fractal lattice network of elastic springs having a strain based fracture criteria. An analysis of the model system supports the power law and shows that lacunarity is an important parameter in differentiating the mechanical strength of trabecular bones of same density. 相似文献
106.
The relationship between the structure of bovine cancellous bone, and its ultrasonic propagation parameters is investigated by means of a novel technique involving the application of large static loads, thereby changing the porosity in a controlled manner. The results show that for frequencies in the range 0.4 to 1 MHz, porosity decreases up to 35% are associated with a reduction in attenuation of up to 500%, whereas the velocity increases by roughly 35% for the same changes. The data taken overall suggest that in determining the ultrasonic attenuation coefficient at these frequencies, the amount of material in a given bone section is significantly less important than the distribution of that material. 相似文献
107.
Tatsuo Suda 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2004,80(9):407
Vitamin D was discovered as an anti-rachitic agent, but even at present, there is no direct evidence to support the concept that vitamin D directly stimulates osteoblastic bone formation and mineralization. It appears to be paradoxical, but vitamin D functions in the process of osteoclastic bone resorption. Osteoclasts, the only cells responsible for bone resorption, develop from hematopoietic cells of the monocyte-macrophage lineage. In 1992, we hypothesized that a membrane-bound factor, designated as “osteoclast differentiation factor (ODF)”, is expressed on the plasma membrane of osteoblasts/stromal cells in response to osteotropic factors including the active form of vitamin D3, 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3]. Recently, four research groups including ours independently identified three key molecules (RANKL, RANK, and OPG) responsible for osteoclastogenesis. A long-sought-after ligand, ODF, was identical to RANKL. RANKL was a member of the membrane-associated TNF ligand family, which induced differentiation of spleen cells (osteoclast progenitors) into osteoclasts in the presence of M-CSF. RANK, a member of the TNF receptor family, was a signaling receptor essential for the RANKL-mediated osteoclastogenesis. OPG, a secreted member of the TNF receptor family, was a decoy receptor for RANKL. The discovery of RANKL, RANK and OPG opens a new era in the study of bone biology and the therapy of several metabolic bone diseases such as osteoporosis, rheumatoid arthritis, and periodontal diseases. 相似文献
108.
复方丹参合剂对去卵巢大鼠骨矿盐代谢的影响 总被引:2,自引:0,他引:2
用测定骨矿盐含量的方法,分析了复方丹参合剂(三种不同剂量)对切除双侧卵巢后的大鼠骨矿盐代谢的影响。将健康4月龄雌性SD大鼠36只,随机分成6组:A组(正常对照组);B组(假去卵巢组);C组(去卵巢组);D组(去卵巢 合剂小剂量组);E组(去卵巢 合剂中等剂量组);F组(去卵巢 合剂大剂量组)。去卵巢手术后1 d开始,连续用药11周。结果表明,去卵巢大鼠骨干质量、干质量/体质量、骨灰质量、骨灰质量/体质量、骨灰质量占骨干质量比等均明显降低,复方丹参合剂可使去卵巢大鼠降低的骨干质量、骨干质量/体质量、骨灰质量、骨灰质量/体质量、骨灰质量占骨干质量比等均显著回升。提示复方丹参合剂具有良好的对抗由于去卵巢引起骨矿盐含量降低和骨丢失作用。 相似文献
109.
Madhavi Z. Martin Nicole Labb Nicolas Andr Ronny Harris Michael Ebinger Stan D. Wullschleger Arpad A. Vass 《Spectrochimica Acta Part B: Atomic Spectroscopy》2007,62(12):1426-1432
Laser-induced breakdown spectroscopy (LIBS) has been used in the elemental analysis for a variety of environmental samples and as a proof of concept for a host of forensic applications. In the first application, LIBS was used for the rapid detection of carbon from a number of different soil types. In this application, a major breakthrough was achieved by using a multivariate analytical approach that has brought us closer towards a “universal calibration curve”. In a second application, it has been demonstrated that LIBS in combination with multivariate analysis can be employed to analyze the chemical composition of annual tree growth rings and correlate them to external parameters such as changes in climate, forest fires, and disturbances involving human activity. The objectives of using this technology in fire scar determinations are: 1) To determine the characteristic spectra of wood exposed to forest fires and 2) To examine the viability of this technique for detecting fire occurrences in stems that did not develop fire scars. These examples demonstrate that LIBS-based techniques are inherently well suited for diverse environmental applications. LIBS was also applied to a variety of proof of concept forensic applications such as the analysis of cremains (human cremation remains) and elemental composition analysis of prosthetic implants. 相似文献
110.
End-stage renal diseases are affecting many patients and as a result, demand to receive dialysis service is growing annually. Morbidity and mortality rates are reported to be higher in comparison with healthy humans. The reason is reported to be the hemoincompatiblity of blood purification membranes, which hinders patients’ lives. Activation of different immune systems in the body, in case of blood-membrane interaction, results in several side effects, of which cardiovascular shocks have been mentioned to be a major one. Efforts to solve this issue have resulted in different generations of dialysis membranes. Zwitterionic immobilized membranes are the latest (third) generation, which owns a higher degree of hemocompatiblity with more stability of immobilized structures. This critical review intends to cover recent efforts conducted over the zwitterionization of polymeric membrane surfaces with the goal of improving hemocompatibility. Different aspects of third-generation membranes are discussed for a better understanding of the current gap and gathering the knowledge to further develop the field. Accordingly, this critical survey provides an in-depth understanding of blood purification membranes zwitterionization for paving the way for the optimum enhancement of hemodialysis membrane hemocompatibility. 相似文献