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991.
Pengde Kang Bin Shen Jing Yang Jingqiu Cheng Fuxing Pei 《Connective tissue research》2013,54(4):171-179
There is a direct relationship between mechanical stress and the progressive collapse of the necrotic region in osteonecrosis of the femoral head. The titanium implant combined with autogenous bone graft and recombinant human bone morphogenetic protein (rhBMP)-2 to repair the defect and prevent collapse of the femoral head was investigated. The femoral head defects were made by the trapdoor procedure and then the defects were filled, respectively, with the titanium implant combined with autogenous bone graft and rhBMP-2, with autogenous bone graft and rhBMP-2, and with autogenous bone graft alone. Roentgenographic and histological examinations were performed at various times postoperatively. The defects were repaired completely and the titanium implant was integrated with the surrounding bone tissues. The defects healed faster than did without rhBMP-2. No trapdoor cartilage collapsed and joint space narrowed. The titanium implant combined with autogenous bone graft and rhBMP-2 can enhance the repairing procedure and prevent the collapse of the femoral head. 相似文献
992.
《Connective tissue research》2013,54(1-4):343-349
Calcium phosphate crystals deposited in the organic matrix synthesized by chick bone osteoblasts in culture were studied by x-ray and electron diffraction, Fourier transform infrared spectroscopy and chemical composition. The amounts of mineral phase deposited with time and the extent of calcification (% of mineral phase in the tissue) were also determined as a function of time, as were the nature of the changes in the short range order of the crystals. The amount of mineral deposited and the extent of calcification increased with time; the tissue not only contained more crystals of apatite, but the extent of calcification also increased with time as it does in vivo. After 30 days of culture the extent of calcification in the cell culture matrix was similar to that in late chick embryonic and early postnatal chick tibiae. The nature of the CO3 and HPD4 environments were similar to those found in vivo although the concentrations of these ions and the changes in their concentrations with time appeared to develop more slowly in cell culture than they do in vivo. However, the general overall pathway of maturation was similar in cell culture to that observed in vivo. 相似文献
993.
《Annals of human biology》2013,40(3):195-205
Background: Secular trends in height and weight are reasonably well documented in Europe. Corresponding observations for skeletal maturation are lacking.Aim: To assess secular trends in height, body mass and skeletal maturity of Portuguese children and adolescents and to provide updated reference values for skeletal maturity scores (SMSs).Subjects and methods: Data for 2856 children and adolescents of 4–17 years, 1412 boys and 1444 girls, from The ‘Madeira Growth Study’ (MGS; 1996–1998) and from the‘Healthy Growth of Madeira Children Study’ (CRES; 2006) were used. Height and body mass were measured. Skeletal maturity was assessed with the Tanner-Whitehouse 2 and 3 methods.Results: Children from CRES were taller and heavier than peers from MGS. Differences in height reached 5.8 cm in boys and 5.5 cm in girls. RUS SMSs did not differ consistently between surveys boys, while higher RUS scores were observed in CRES girls. Adult RUS SMSs for MGS and CRES combined were attained at 15.8 years in boys and 14.8 years in girls. Corresponding ages for adult Carpal SMSs were 14.4 and 14.0, respectively.Conclusion: The short-term trends for height and mass were not entirely consistent with the trends in RUS and Carpal SMSs and SAs. 相似文献
994.
《Growth factors (Chur, Switzerland)》2013,31(3):149-156
Several studies have shown that bone morphogenetic proteins (BMPs) can influence adipogenic and osteogenic cell lineages. We have shown that a peptide derived from BMP-9 (pBMP-9) at 400 ng/ml inhibits the proliferation of preosteoblasts and induces differentiation. We have now determined the effects of pBMP-9 (400 ng/ml) and equimolar concentrations of BMP-2 (100 ng/ml), BMP-9 (84.6 ng/ml) and pBMP-9 (9.04 ng/ml) on human white preadipocytes (HWP). pBMP-9 dose dependently reduced the proliferation of HWP without affecting the number of apoptotic cells. Incubation of the cells for 1 h with BMP-2, BMP-9 or pBMP-9 activated the Smad1/5/8 pathway, while incubation for 7 days in adipocyte differentiation (AD) serum-free medium containing ciglitazone and equimolar concentrations of BMP-2, BMP-9 or pBMP-9 enhanced the levels of mRNA of the adipogenic markers aP2 and adipoQ and increased the number of lipid vesicles. Thus, pBMP-9, like BMP-9, can increase the AD of HWP in AD serum-free medium. 相似文献
995.
ObjectiveTo assess the preliminary evidence for the efficacy and safety of an immediate functional progression program to treat adolescent athletes with an active spondylolysis.DesignProspective single-arm trial.SettingHospital-based sports medicine and physical therapy clinic.ParticipantsTwelve adolescent athletes (14.2 ± 2 years, 25% female) with an active spondylolysis.Main outcome measuresClinical outcomes included time out of sport, Micheli Functional Scale (Function and Pain) and adverse reactions. Clinical outcomes were assessed at baseline, 1 month, 3 months and 6 months. Magnetic resonance imaging was performed at baseline and 3 months to confirm diagnosis and assess healing of lesion.ResultsEleven participants (92%) fully returned to sport in a median time of 2.5 months (75 days; interquartile range 55 days, 85 days). All participants demonstrated marked improvements in pain and function by the end of the program. One participant (8%) had an adverse reaction during care with a significant recurrence of LBP and had not returned to sport by 6 months. Magnetic resonance imaging demonstrated improvement of the spondylolytic lesion in all but one participant.ConclusionThe immediate functional progression program appears a viable method for treating active spondylolysis and warrants future research. 相似文献
996.
Background: Few studies have examined growth data from adolescent girls in Latin America and almost none have been conducted in Nicaragua. Thus this study examines growth data from Nicaraguan adolescent girls.Aim: This study describes cross-sectional growth data from a sample of Nicaraguan girls. These data are compared with data from Mexican–US and Guatemalan girls. It is hypothesized that (a) Mexican–US and Guatemalan wealthy ladina girls will show better indicators of nutritional status when compared with the Nicaraguan girls, and (b) the Nicaraguan girls will show similar anthropometric indicators when compared with poor Guatemalan girls.Subjects and Methods: Anthropometric and age at menarche data were collected from a sample of 154 adolescent girls ages 10–17 years living in Managua, Nicaragua.Results: The findings revealed that these girls are significantly shorter and lighter than US, Mexican–US and wealthy Guatemalan adolescent girls. These girls are also significantly taller and heavier than their poor Guatemalan counterparts.Conclusion: This study reveals that the Nicaraguan girls are undernourished when compared with other Latin American girls living in an improved overall environment. The data also reveal that the Nicaraguan girls have better indicators of nutritional status when compared with a cohort of poor Guatemalan girls. 相似文献
997.
Inflammatory bowel disease (IBD) is commonly believed to increase the risk of bone mineral loss, leading to osteoporosis and an increased risk of disabling fractures. In this narrative review, we will presenting a summary of the published medical literature in regards to the relationship between IBD and the development of osteoporosis, bone mineral loss, and fractures. We will explore the epidemiology of metabolic bone disease in IBD, focusing on the prevalence and both the general and IBD-specific risk factors for the development of osteoporosis and of fracture in persons with IBD. We will also examine the role of the inflammatory process in IBD promoting excessive bone mineral loss, as well as the role that low body mass, corticosteroid use, diet, and nutrient malabsorption play in contributing to bone disease. Last, we will discuss our recommendation for: screening for osteoporosis in IBD patients, the use of preventative strategies, and therapeutic interventions for treating osteoporosis in persons with IBD. 相似文献
998.
Franz Jakob Regina Ebert Anita Ignatius Takashi Matsushita Yoshinobu Watanabe Juergen Groll Heike Walles 《Maturitas》2013
Osteoporosis is a polygenetic, environmentally modifiable disease, which precipitates into fragility fractures of vertebrae, hip and radius and also confers a high risk of fractures in accidents and trauma. Aging and the genetic molecular background of osteoporosis cause delayed healing and impair regeneration. The worldwide burden of disease is huge and steadily increasing while the average life expectancy is also on the rise. The clinical need for bone regeneration applications, systemic or in situ guided bone regeneration and bone tissue engineering, will increase and become a challenge for health care systems. Apart from in situ guided tissue regeneration classical ex vivo tissue engineering of bone has not yet reached the level of routine clinical application although a wealth of scaffolds and growth factors has been developed. Engineering of complex bone constructs in vitro requires scaffolds, growth and differentiation factors, precursor cells for angiogenesis and osteogenesis and suitable bioreactors in various combinations. The development of applications for ex vivo tissue engineering of bone faces technical challenges concerning rapid vascularization for the survival of constructs in vivo. Recent new ideas and developments in the fields of bone biology, materials science and bioreactor technology will enable us to develop standard operating procedures for ex vivo tissue engineering of bone in the near future. Once prototyped such applications will rapidly be tailored for compromised conditions like vitamin D and sex hormone deficiencies, cellular deficits and high production of regeneration inhibitors, as they are prevalent in osteoporosis and in higher age. 相似文献
999.
《Journal of medical engineering & technology》2013,37(5):275-282
Objectives:?An experimental biomechanical evaluation of an instrumented intramedullary nail (TriGen® META Nail, Smith&Nephew®) was undertaken. The objectives were two-fold. The first was to identify the most sensitive strain gauge positions and orientations on the nail, and the second was to demonstrate that the nail was capable of detecting changes in stiffness of the nail–bone composite. The function of the instrumented nail is to quantify fracture healing objectively and directly, and so to predict delayed repair or non-union 2 months before current methods.Methods:?Eight flat pockets were machined onto the surface of the nail and three strain gauges attached in each pocket. The instrumented nail was inserted into fourth generation biomechanical grade Sawbones® tibiae with three different fracture configurations as well as into a non-fractured bone. The nail–bone composite was loaded in three-point bending at five positions to determine the strain changes in each of the eight strain gauge pockets located along the length of the nail. To simulate callus in the simplest way and to increase the stiffness of the nail–bone composite, loops of duct tape in multiples of four were applied over the fracture locus. A three-point loading jig was used to obtain the change in strain with increasing stiffness. Relative displacement of the bone ends was quantified using radiostereometric analysis.Results:?There was no single position of greatest strain sensitivity for all fracture types. The greatest change in strain occurred when the strain gauge pocket and fracture line were closest. Applying the loading moment directly over the strain gauge pocket also maximised its sensitivity. The duct tape callus simulation showed that the instrumented nail was able to detect a change in stiffness of less than 4.1 Nm/°.Conclusions:?It has been shown that the instrumented nail can detect physiologically relevant changes in stiffness, and so to provide a useful function as an objective monitor of fracture repair. 相似文献
1000.
目的 探讨骨巨细胞瘤的组织发生以及与肿瘤复发、侵袭、恶变等生物学行为相关的因素.方法 从临床、影像学、手术方式、病理形态、免疫表达和随访结果等方面对2005至2011年间收集的123例骨巨细胞瘤进行分析和研究.结果 骨巨细胞瘤的术后复发率与术前骨巨细胞瘤的影像学分级(P=0.032)、CD147 (P=0.034)和p53(P =0.005)的过表达以及手术方式(P =0.048)有明显相关性,但与骨巨细胞瘤的髓内浸润、骨皮质浸润、骨旁软组织浸润、脉管内瘤栓、单核间质细胞的梭形变、核分裂象多少、Ki-67阳性指数、凝固性坏死、继发性动脉瘤样骨囊肿、出现反应性骨等形态学改变均缺乏明显相关性,骨巨细胞瘤中单核间质细胞p63阳性率(79.7%,94/118)明显高于软骨母细胞瘤(44.7%,21/47)、骨肉瘤(22.2%,10/45)等其他富于巨细胞的骨肿瘤.结论 骨巨细胞瘤是一种有低度恶性潜能的肿瘤,形态学特征难以预测其生物学行为.p63阳性、PGM-1阴性的单核间质细胞是其肿瘤成分,此种细胞p53的过表达以及骨巨细胞瘤各种细胞成分(包括反应性单核巨噬细胞和多核巨细胞)CD147的过表达与骨巨细胞瘤的侵袭、复发和恶变有关.术前根据骨巨细胞瘤的影像学分级选择合适的手术方式是减少复发最重要的因素. 相似文献