Letteratura scientifica selezionata sul tema "Osteoporosis Tibia Rats"
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Articoli di riviste sul tema "Osteoporosis Tibia Rats"
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Dreyer, Chris H., Marina Rasmussen, Rasmus Hestehave Pedersen, Søren Overgaard, and Ming Ding. "Comparisons of Efficacy between Autograft and Allograft on Defect Repair In Vivo in Normal and Osteoporotic Rats." BioMed Research International 2020 (March 4, 2020): 1–9. http://dx.doi.org/10.1155/2020/9358989.
Testo completoAbstract (sommario):
Introduction. In the field of orthopaedic surgery, the use of osteogenic material in larger defects is essential. Autograft and allograft are both known methods, and autograft is believed to be the best choice. But autograft is associated with additional invasive procedures which can prove difficult in fragile patients and can cause local side effect after bone harvest. For feasible purposes, the use of allograft is hereby rising and comparing efficacies, and the differences between autograft and allograft are essential for the clinical outcome for the patients. Method. 24 female Norwegian brown rats were included, 12 normal rats and 12 induced with osteoporosis (OP). OP inducement was verified in vivo by bone volume fraction (BV/TV) at 90 days after ovariectomy (OVX). The primary surgery in each rat consisted of a 2.5×3 mm hole in the proximal tibia, bilaterally. Autograft and allograft were randomly allocated in the right and left tibia. After an observation of 21 days, the rats were sacrificed. Tibia samples were harvested, micro-CT scanned for bone inducement and microarchitectural properties, and then embedded for histology. Results. The OP induction was verified three months after the OVX by a reduction of 68.5% in the trabecular bone BV/TV compared to normal bone. Microarchitectural analysis and histology showed no significant differences in the bone-forming capabilities between autograft and allograft in normal or osteoporotic bone after 3 weeks. Conclusion. This study did not demonstrate any difference between autograft and allograft in a normal or osteoporotic rat tibial defect model after 21 days, suggesting allograft is a good alternative to autograft.
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Shi, Na, Chu-Qiong Zhang, Long Han, and Gang Ouyang. "Effect of Acupoint Catgut Embedding on Intestinal Flora in Rats with Ovariectomized Osteoporosis." Acupuncture & Electro-Therapeutics Research 46, no. 4 (2021): 307–18. http://dx.doi.org/10.3727/036012921x16281724938230.
Testo completoAbstract (sommario):
Objectives: By observing the effect of acupoint catgut embedding on the intestinal flora of ovariectomized osteoporotic rats, the correlation between the regulation of intestinal flora and the prevention and treatment of osteoporosis was discussed preliminarily. Methods: By observing the effect of acupoint catgut embedding on the intestinal flora of ovariectomized osteoporotic rats, the correlation between the regulation of intestinal flora and the prevention and treatment of osteoporosis was discussed preliminarily. Result: Compared with Group A and Group B, bone mineral density (BMD) of femur and tibia in Group C decreased significantly (p<0.05), indicating successful modeling. Compared with Group C, BMD of femur and tibia in Group D was significantly increased (p<0.05). Compared with Group A and Group B, content of serum estrogens, calcium, and PTHrP in Group C were significantly decreased (p<0.05 or p<0.01). Content of serum estrogen, calcium, and PTHrP in Group D were significantly higher than those in Group C (p<0.05 or p<0.01). Compared with Group A and Group B, the abundance of mollicutes, actinobacteria, acidobacteria, chloroflexi and fusobacteria in group C was significantly increased. The abundance of probiotics in Group D such as lactobacillales, (lactobacillaceae, lactobacillus), bacillales, and streptococcus was significantly higher than that in Group C (p<0.05). The content of SCFAs such as acetic acid, butyric acid, iso-valeric acid, valeric acid and caproic acid in Group D were significantly higher than those in Group C, with statistical significance (p<0.05). Conclusions: Acupoint catgut embedding can effectively improve BMD, increase content of estrogen, calcium, PTHrP and SCFAs. Furthermore, embedding can also improve the abundance of probiotics and reduce the abundance of pathogenic bacteria. The changes of intestinal flora were correlated with the changes of estrogen and calcium, which may be one of the mechanisms of acupoint catgut embedding in the prevention and treatment of osteoporosis.
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Fang, Wen, Shifang Zhao, Fuming He, Li Liu, and Guoli Yang. "Influence of Simvastatin-Loaded Implants on Osseointegration in an Ovariectomized Animal Model." BioMed Research International 2015 (2015): 1–7. http://dx.doi.org/10.1155/2015/831504.
Testo completoAbstract (sommario):
The success of bone implants in the presence of osteoporosis is limited by lack of osseointegration between the implant and the natural bone. This study applied an electrochemical process to deposit simvastatin-nanohydroxyapatite (HA) coatings on porous implant surfaces and investigated the effects of these simvastatin-HA coatings on implant surfaces in an animal model of osteoporosis. In this study, simvastatin-HA coated implants were inserted into the tibia of osteoporotic rats. After 2, 4, and 12 weeks, tissue was retrieved for histomorphometric evaluation. The results indicated that the simvastatin-HA coatings increased bone-implant contact and new bone formation around implant surfaces. In conclusion, implants loaded with simvastatin by an electrochemical process improved implant osseointegration in osteoporotic rats. Furthermore, the increased concentration of simvastatin could affect the osseointegration, but the dose-effects also need further investigation.
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Zhang, Zhiguo, Jiazi Dong, Meijie Liu, et al. "Therapeutic Effects ofCortex acanthopanacisAqueous Extract on Bone Metabolism of Ovariectomized Rats." Evidence-Based Complementary and Alternative Medicine 2012 (2012): 1–8. http://dx.doi.org/10.1155/2012/492627.
Testo completoAbstract (sommario):
The aim of this study was to evaluate effects of aqueous extract fromCortex acanthopanacis(CAE) on osteoporosis rats induced by ovariectomy (OVX) using aqueous extract fromFolium Epimedii(FEE) as positive control agent. Three-month-old female rats that underwent OVX were treated with CAE. After 12 weeks, bone mineral density (BMD) and indices of bone histomorphometry of tibia were measured. Levels of protein and mRNA expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) in tibia were evaluated. In addition, the serum concentrations of osteocalcin (OC), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), calcitonin (CT), and parathyroid hormone (PTH) were determined. Administration of CAE significantly prevented OVX-induced rats from gain of the body weight. Treatment with CAE increased bone mass remarkably and showed a significant inhibitory effect on bone resorption by downregulating significantly the expression of RANKL in tibia of OVX rats. Meanwhile, treatment of CAE significantly reduced serum level of IL-1βand increased level of CT in OVX rats. This suggests that CAE has the potential to be used as an alternative therapeutic agent for postmenopausal osteoporosis.
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Sun, Bo, Tian Su, Zhibin Meng, and Songjie Tang. "Anhuienoside C Ameliorates Osteoclast Differentiation in Ovariectomy-Induced Osteoporosis by Regulating RANKL/Wnt Signaling Pathways." Current Topics in Nutraceutical Research 20, no. 1 (2020): 51–55. http://dx.doi.org/10.37290/ctnr2641-452x.20:51-55.
Testo completoAbstract (sommario):
Postmenopausal and ovariectomy-induced osteoporosis is the most common bone disorder. While pharmacotherapy has been valuable in the management of osteoporosis, it has been associated with undesired side effects. Plant bioactives with minimal side effects have been seen as adjunct to classical therapy. Herein, we have evaluated the protective effect of anhuienoside C (AC) in a rat model of ovariectomy-induced osteoporosis. The treatment of osteoporotic rats with AC caused dose-dependent favorable changes in biochemical markers of bone formation and metabolism (osteocalcin, C-telopeptide of type 1 collagen, and procollagen type 1 N-terminal propeptide), enhanced bone mineral density, and decrease in proinflammatory mediators of inflammation and RANKL/Wnt pathway proteins. Furthermore, histopathologic changes in the tibia support beneficial effects of AC. In conclusion, our result reveals that treatment with AC shows beneficial effect against ovariectomy-induced osteoporosis by regulating the RANKL/Wnt pathway.
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Komrakova, Marina, Stephan Sehmisch, Mohammad Tezval, et al. "Impact of 4-methylbenzylidene camphor, daidzein, and estrogen on intact and osteotomized bone in osteopenic rats." Journal of Endocrinology 211, no. 2 (2011): 157–68. http://dx.doi.org/10.1530/joe-11-0096.
Testo completoAbstract (sommario):
The study investigated the influence of 4-methylbenzylidene camphor (4-MBC), daidzein, and estradiol-17β-benzoate (E2) on either intact or osteotomized cancellous bone in ovariectomized (Ovx) rats. Three-month old Ovx rats were fed with soy-free (SF) diet over 8 weeks; thereafter, bilateral transverse metaphyseal osteotomy of tibia was performed and rats were divided into groups: rats fed with SF diet and SF diet supplemented with 4-MBC (200 mg), daidzein (50 mg), or E2(0.4 mg) per kilogram body weight. After 5 or 10 weeks, computed tomographical, biomechanical, histological, and ashing analyses were performed in lumbar spine and tibia of 12 rats from each group. 4-MBC and E2improved bone parameters in lumbar spine and tibia, were not favorable for osteotomy healing, and decreased serum osteocalcin level. However, daidzein improved bone parameters to a lesser extent and facilitated osteotomy healing. For lumbar spine, the bone mineral density was 338±9, 346±5, 361±6, and 360±5 mg/cm3in SF, daidzein, 4-MBC, and E2, respectively, after 10 weeks. For tibia, the yield load was 98±5, 114±3, 90±2, and 52±4 N in SF, daidzein, 4-MBC, and E2, respectively, after 10 weeks. Serum daidzein was 54±6 ng/ml in daidzein group and equol was not detected.AlpandIgf1genes were down-regulated in callus after daidzein and E2compared with 4-MBC (week 5). The response of bone tissue and serum markers of bone metabolism could be ordered: daidzein<4-MBC<E2. Treatments were more effective after 5 vs 10 weeks. In SF group, bone structure was impaired after 5 weeks and improved after 10 weeks probably due to adaptation mechanisms to osteoporosis. In conclusion, it is conceivable that 4-MBC may improve bone tissue in osteoporotic organisms; osteoporotic patients with fractures could benefit from daidzein treatment.
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PASSALI, C., A. PATSAKI, P. LELOVAS, et al. "Red wine polyphenols modulate bone loss in the ovariectomized rat model of postmenopausal osteoporosis." Journal of the Hellenic Veterinary Medical Society 70, no. 2 (2019): 1541. http://dx.doi.org/10.12681/jhvms.20860.
Testo completoAbstract (sommario):
The aim of this study was to examine the effect of Red Wine Polyphenols (RWPs) extract on bone mineral density (BMD) in the ovariectomized (OVX) rat model. Thirty-five 10-month-old Wistar rats were separated into controls (CTRL), OVX and OVX plus RWPs in their drinking water (dose, 50 mg/kg body weight per day), starting immediately after OVX for 6 months. Βody and uterine weight, BMD of the tibia at baseline, 3 and 6 months post-OVX, and 3-pointing bending of the femur, were examined. Statistical comparison of the total tibia BMD within groups during the study period showed a significant reduction in the OVX and OVX+RWPs groups both from baseline to 3 and 6 months and from 3 to 6 months, whereas in the CTRL group, there was no significant change. For the proximal tibial metaphysis, comparison of BMD percentage changes from baseline to 3 months and 6 months and from 3 to 6 months revealed highly statistical differences between OVX and OVX+RWPs groups (P = 0.000). OVX induced a significant reduction of biomechanical parameters as expected; the 3-point bending test showed that the maximum force before fracture, energy absorption and fracture stress significantly increased in the OVX group treated with RWPs compared with the nontreated OVX rats (P = 0.048, P = 0.002 and P = 0.003, respectively). Dietary intake of RWPs for 6 months significantly prevented trabecular bone loss and improved bone strength in estrogen-deficient ovariectomized rats.
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Saul, D., M. Ninkovic, M. Komrakova, et al. "Effect of zileuton on osteoporotic bone and its healing, expression of bone, and brain genes in rats." Journal of Applied Physiology 124, no. 1 (2018): 118–30. http://dx.doi.org/10.1152/japplphysiol.01126.2016.
Testo completoAbstract (sommario):
Estrogen deficiency and aging are associated with osteoporosis, impaired bone healing, and lower cognitive performance. Close functional and physical connections occur between bone and the central nervous system. An anti-inflammatory drug, zileuton (which is an inhibitor of arachidonate 5-lipoxygenase), is known to have a positive effect on bone tissue repair and brain ischemia. We studied the effect of zileuton on osteopenic bone and its healing and on the genes considered to be crucial for the cross talks between bone and brain. Three-month-old Sprague-Dawley rats were ovariectomized or left untreated. After 8 wk, bilateral metaphyseal tibia osteotomy with plate osteosynthesis was performed in all rats. Ovariectomized rats were fed with food containing zileuton (1, 10, or 100 mg/kg body wt) for 5 wk. In tibiae, bone volume, callus and cortical volume, and gene expression of osteocalcin and alkaline phosphatase were enhanced by zileuton (10 or 100 mg); biomechanical properties and bone density were not changed. In femur, zileuton enlarged cortical volume distal and trabecular volume proximal, decreasing their density. The expression level of brain Sema3a, known to regulate bone mass positively, was downregulated after ovariectomy. In contrast, bone Sema4d, a negative regulator of bone mass, was upregulated in the tibia callus after ovariectomy, whereas zileuton treatment (10 or 100 mg) resulted in reverse effects. Here, we describe for the first time the expression of Rbbp4 mRNA and its increase in tibia after ovariectomy. Zileuton caused downregulation of Rbbp4 in the hippocampus and had an effect on bone healing, changed the expression of genes involved in cross talk between bones and brain, and may be a potent drug for further examination in estrogen deficiency-related dysfunction(s). NEW & NOTEWORTHY Zileuton, a 5-lipoxygenase inhibitor, increased bone volume, callus and cortical volume in osteotomized tibia, and trabecular and cortical volume in femur. Although the expression of Sema3a (positively regulating bone mass) in brain was downregulated and Sema4d (negatively regulating bone mass) was upregulated in tibia callus after ovariectomy, zileuton could counteract these effects. Rbbp4 (involved in age-related memory loss) was increased in tibia callus after ovariectomy.
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Zhuang, Yongliang, Xiaodong Sun, Bingtong Liu, Hu Hou, and Yun Sun. "Effects of Rambutan Peel (Nepheliumlappaceum) PhenolicExtract on RANKL-Induced Differentiation of RAW264.7 Cells into Osteoclasts and Retinoic Acid-Induced Osteoporosis in Rats." Nutrients 12, no. 4 (2020): 883. http://dx.doi.org/10.3390/nu12040883.
Testo completoAbstract (sommario):
Previous studies have shown that rambutan peel phenolic (RPP) extract has excellent biological activities due to its abundant phenolic content and profile. In this study, the potential anti-osteoporosis (OP) effects of RPP were evaluated by suppressing receptor activator nuclear factor-kappa B ligand (RANKL)-induced differentiation of RAW264.7 cells into osteoclasts and amelioratingretinoic acid-induced OP in rats. Our results showed that RPP efficiently decreased the formation of tartrate-resistant acid phosphatase (TRAP)-positive cells and reduced total TRAP activity in RAW264.7 cells under RANKL stimulation. RPP treatment significantlyameliorated retinoid acid-induced calcium loss in rats (p < 0.05). The serum phosphorus level of osteoporotic rats was increased by RPP treatment, and the serum levels of total alkaline phosphatase and osteocalcin in osteoporotic rats were further reduced. RPP treatment improved the qualities of the femur and tibia, such asbone mineral density, bone length, bone maximum load, cortical bone area ratio, and trabecularelative bone density in osteoporotic rats to some extent. Furthermore, histological analysis showed that RPP effectively improved the bone microstructure of osteoporotic rats by regulating the cortical bone thickness and trabecular bone separation. These results indicate that RPP could have potential applications as a newnutraceutical and functional food in the prevention of OP.
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Ham, Ju Ri, Ra-Yeong Choi, Hae-In Lee, and Mi-Kyung Lee. "Protective Effects of Methoxsalen Supplementation on Chronic Alcohol-induced Osteopenia and Steatosis in Rats." Molecules 25, no. 5 (2020): 1177. http://dx.doi.org/10.3390/molecules25051177.
Testo completoAbstract (sommario):
Osteopenia or osteoporosis occurs frequently in alcoholics and patients with alcoholic fatty liver disease. Methoxsalen (MTS), 8-methoxypsoralen, improved osteoporosis in ovariectomized and diabetic mouse models; however, its effects on alcohol-induced osteopenia and steatosis have not been reported. This study examined the effects of MTS on alcohol-induced bone loss and steatosis. Rats in the alcohol groups were fed a Liber-DeCarli liquid diet containing 36% of its calories as alcohol. MTS was at 0.005% in their diet, while alendronate (positive control; 500 μg/kg BW/day) was administered orally for eight weeks. The pair-fed group received the same volume of isocaloric liquid diet containing dextrin-maltose instead of alcohol as the alcohol control group consumed the previous day. In the alcohol-fed rats, the MTS and alendronate increased the bone volume density, bone surface density and trabecular number, while the bone specific surface, trabecular separation and structure model index were decreased in the tibia. MTS down-regulated tibial tartrate-resistant acid phosphatase 5 (TRAP) expression compared to the alcohol control group. MTS or alendronate prevented chronic alcohol-induced hepatic lipid accumulation and the triglyceride level in the alcohol-fed rats by decreasing the lipogenic enzyme activities and increasing the fatty acid oxidation enzyme activities. MTS reduced significantly the serum levels of alcohol, TRAP and tumor necrosis factor-α compared to the alcohol control group. Overall, these results suggest that MTS is likely to be an alternative agent for alcoholic osteopenia and hepatosteatosis.
Tesi sul tema "Osteoporosis Tibia Rats"
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Romanchak, Marcia A. "Effect of increased energy in a restricted diet on bone mineral composition and breaking load of young rat tibias." Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2369.
Testo completoAbstract (sommario):
Thesis (M.S.)--West Virginia University, 2002.<br>Title from document title page. Document formatted into pages; contains viii, 59 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 53-57).
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Freitas, Deborah Queiroz de 1977. "Avaliação do efeito radioprotetor do selenito de sodio na reparação de tibias de ratas ovariectomizadas." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290143.
Testo completoAbstract (sommario):
Orientador: Solange Maria de Almeida<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba<br>Made available in DSpace on 2018-08-10T00:43:38Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007<br>Resumo: A osteoporose e a irradiação são fatores que interferem no processo de reparação óssea e podem ocorrer simultaneamente, especialmente em mulheres idosas. Atualmente, várias substâncias, conhecidas como radioprotetores, têm sido estudadas, pois minimizam os efeitos deletérios da radiação; dentre eles, pode-se citar o selênio. O objetivo desse trabalho foi avaliar o efeito radioprotetor do selenito de sódio no processo de reparo ósseo em ratas ovariectomizadas submetidas à irradiação. Para isso, oitenta ratas foram submetidas à ovariectomia e divididas em quatro grupos: ovariectomizado, ovariectomizado/selênio, ovariectomizado/irradiado e ovariectomizado/selênio/irradiado. Quarenta dias após, um defeito ósseo foi confeccionado nas tíbias dos animais. Dois dias após essa cirurgia, os animais dos grupos ovariectomizado/selênio eovariectomizado/selênio/irradiado receberam 0,8 mg Se/Kg de peso corpóreo. No dia seguinte, apenas os animais pertencentes aos grupos ovariectomizado/irradiado e ovariectomizado/selênio/irradiado receberam 10 Gy de radiação X na região dos membros inferiores. Os animais foram sacrificados 7, 14, 21 e 28 dias após a cirurgia. O processo de reparação óssea foi avaliado por análise morfológica, utilizando-se a coloração pelo Tricrômico de Masson, e por análise do número de trabéculas ósseas e da birrefrigência (coloração pelo Picrosírius). Pela análise morfológica, foi possível observar um atraso no processo de reparo ósseo nos animais do grupo ovariectomizado/irradiado e similaridade entre os grupos ovariectomizado, ovariectomizado/selênio e ovariectomizado/selênio/irradiado, o que demonstrou o efeito radioprotetor do selênio sem toxicidade<br>Abstract: Osteoporosis and ionizing radiation affect the bone healing and people can suffer both conditions, especially older women. At the moment, antioxidant radioprotectors have been evaluated, such selenium compounds. This study aimed at evaluating the selenium protection in the bone repair process in ovariectomized rats submitted to an irradiation procedure. For this purpose, eighty ovariectomized female Wistar rats were randomly divided in four experimental groups: ovariectomized, ovariectomized/selenium, ovariectomizedlirradiated and ovariectomized/selenium/irradiated. Abone defect was made on all animals' tibias forty days after ovariectomy. Two days after surgery, only ovariectomized/selenium and ovariectomized/seleniumlirradiated rats received 0.8 mg Se/Kg. Three days after surgery, only ovariectomized irradiated and ovariectomized/selenium/irradiated rats received 10 Gy of X rays on the lower limbs region. The animals were sacrificed 7, 14, 21 and 28 days after surgery in order to assess the repair process, which was evaluated by morphologic analysis in Masson Tricromic. lt was also evaluated by analysis of trabecular bone number in Masson Tricromic and birefringence analysis in Picrosirius. It was possible to observe a delay in the bone repair process in the irradiated/ovariectomized group and similarity between ovariectomized, ovariectomized/selenium and ovariectomized/selenium/irradiated, which proved the selenium radioprotection without its toxicity<br>Doutorado<br>Radiologia Odontologica<br>Doutor em Radiologia Odontológica
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Ade, Peter Chi. "Effect of prebiotics, probiotics and synbiotics on Tibia trabecular structure in ovariectomized rats a model for postmenopausal osteoporosis /." 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=014731061&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
Testo completo
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Lieberwirth, Peggy. "Einfluss einer horizontalen Ganzkörpervibration unter verschiedenen Frequenzen auf die Frakturheilung an der osteopenen Rattentibia." Doctoral thesis, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E4A4-2.
Testo completo
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Zimmer, Sebastian. "Wirkung der vertikalen Ganzkörpervibration auf den gesunden und auf den osteoporotischen Knochen der weiblichen Ratte – eine fpVCT-Analyse des ersten Lendenwirbelkörpers und der osteotomierten Tibia." Doctoral thesis, 2017. http://hdl.handle.net/11858/00-1735-0000-0023-3E3C-B.
Testo completo
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Bösch, Malte. "Vergleichende Analyse der Effektivität von horizontaler und vertikaler Ganzkörpervibration auf die osteoporotische Tibiafrakturheilung im Rattentiermodell." Doctoral thesis, 2016. http://hdl.handle.net/11858/00-1735-0000-002B-7CEF-D.
Testo completoAbstract (sommario):
Osteoporose ist eine Krankheit, die weltweit Millionen Menschen betrifft und in Anbetracht der überalternden Gesellschaft in Zukunft weiter an Relevanz gewinnen wird. Dass sich eine Ganzkörpervibration vorteilhaft auf Osteoporose auswirken kann, wurde schon in vorausgegangenen Studien belegt (Rubin et al. 2001b; Flieger et al. 1998; Oxlund et al. 2003; Sehmisch et al. 2009; Stuermer et al. 2010a; Stuermer et al. 2010b). Jedoch konnte bisher keine Klarheit über die optimale Anwendung (Dauer, Häufigkeit, Frequenz, Ausrichtung, Amplitude) gewonnen werden. Die bisherigen Versuche unterschieden sich lediglich in den verwendeten Frequenzen und der Therapiedauer.
Um die unterschiedlichen Einflüsse von vertikaler und horizontaler Vibration auf die osteoporotische Frakturheilung zu untersuchen, wurde in der vorliegenden Arbeit ein Tierversuch mit 90 weiblichen Ratten durchgeführt. 15 wurden scheinoperiert und 75 wurden ovarektomiert. Innerhalb einer Latenzzeit von 8 Wochen entwickelten die ovarektomierten Versuchstiere eine Osteoporose. Im Folgenden wurden alle Tiere an der Tibiametaphyse standardisiert osteotomiert und mittels Plattenosteosynthese versorgt. Es wurden sechs Versuchsgruppen gebildet: Vier Gruppen wurden einer horizontalen bzw. vertikalen Ganzkörpervibration mit 35 Hz oder 70 Hz ausgesetzt (35Hz vert, 70Hz vert, 35Hz horiz und 70Hz horiz). Die übrigen zwei Gruppen erhielten keine Ganzkörpervibration, wobei eine Gruppe aus nicht ovarektomierten (SHAM) und die andere Gruppe aus Tieren nach Ovarektomie bestand (OVX). Die Ganzkörpervibration wurde zweimal täglich über einen Zeitraum von vier Wochen mit einer Amplitude von 0,5 mm durchgeführt. Nach Beendigung dieses Zeitraumes wurden die Tiere per Dekapitation getötet und die Tibiae entnommen.
Anschließend wurden ein biomechanischer Test, eine μCT-Untersuchung, eine mikroradiographische Untersuchung sowie eine polychrome Sequenzmarkierung durchgeführt. Die ersten beiden Untersuchungen konnten am präparierten Knochen vorgenommen werden. Die letzteren erfolgten nach Einbettung der Knochen in Methylmetacrylat und der Anfertigung von ca. 120 µm dicken histologischen Schnitten.
Der biomechanische Test zeigte keine signifikante Veränderung der Elastizität oder der Streckgrenze in allen Gruppen zueinander. Die biomechanischen Eigenschaften des Kallus konnten nur tendenziell bei den hohen Frequenzen von 70 Hz vertikal und 70 Hz horizontal verbessert werden.
In der μCT-Untersuchung konnte weder durch horizontale noch durch vertikale Ganzkörpervibration ein signifikanter positiver Einfluss auf die Frakturheilung im Vergleich zur osteoporotischen Kontrollgruppe nachgewiesen werden. Es zeigten sich jedoch positive Tendenzen durch die horizontale Vibration bei 70 Hz. Die mikroradiographische Untersuchung ergab einen positiven Einfluss der vertikalen und der horizontalen WBV bei 70 Hz. Die horizontale Vibration bei 70 Hz konnte im Vergleich zur osteoporotischen Kontrollgruppe die Kortikalisdicke distal ventral, den Knochendurchmesser proximal, die Kallusdicke ventral, die Knochendichte des ventralen und die des endostalen Kallus verbessern.
In der polychromen Sequenzmarkierung konnte insgesamt durch die WBV eine Verschlechterung der frühen und eine Verbesserung der mittleren und späten osteoporotischen Frakturheilung gezeigt werden. In der frühen Phase wirkten sich ventral sowie endostal alle Frequenzen nachteilig aus. In der mittleren Phase war die horizontale Vibration bei 70 Hz in Bezug auf die dorsale Kallusfläche signifikant vorteilhaft gegenüber der osteoporotischen Kontrollgruppe. In der späten Phase erreichte die Gruppe mit horizontaler 35 Hz-Therapie in Bezug auf die ventrale Kallusfläche gegenüber der osteoporotischen Gruppe und der Gruppe mit vertikaler 35 Hz-Therapie signifikante Steigerungen. Dorsal zeigten beide horizontalen Frequenzen signifikant größere Kallusflächen als die Gruppe mit vertikaler 35 Hz-Therapie.
In der Zusammenschau aller durchgeführten Untersuchungen dieser Arbeit kristallisierte sich die horizontale Ganzkörpervibration bei 70 Hz als die vorteilhafteste Frequenz heraus, um die osteoporotische Frakturheilung an der Tibiametaphyse positiv zu beeinflussen.
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Utesch, Clara Marianne. "Einfluss der vertikalen Ganzkörpervibration auf die metaphysäre Frakturheilung der gesunden und osteoporotischen Tibia im Ratten-Tiermodell." Doctoral thesis, 2016. http://hdl.handle.net/11858/00-1735-0000-0028-8719-D.
Testo completo
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Trautmann, Lukas Michael. "Einfluss der vertikalen Ganzkörpervibration verschiedener Frequenzen auf die Frakturheilung der osteoporotischen Ratte." Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-992A-F.
Testo completoAbstract (sommario):
Um experimentell zu klären, ob bestimmte Vibrationsfrequenzen zur osteoanabolen Stimulation des Knochens und speziell zur Verbesserung der Frakturheilung bei Osteoporose geeigneter sind als andere, wurde in dieser Arbeit die Frakturheilung an der proximalen Tibiametaphyse der ovarektomierten Ratte unter einer vertikalen Vibrationsbehandlung mit Frequenzen von 35, 50, 70 und 90 Hz vergleichend untersucht. Die Tiere wurden dafür nach Tibiaosteotomie und Plattenosteosynthese über 30 Tage für jeweils 15 Minuten der für ihre Gruppe spezifischen Vibrationsfrequenz ausgesetzt. Die Amplitude der Vibration betrug dabei stets 0,5 mm.
Die quantitative Analyse des Frakturkallus mittels Mikroradiographie und Micro-CT ergab deutliche Anhaltspunkte für eine überlegene osteoanabole Potenz der 70Hz-Vibration in Gestalt einer gegenüber allen anderen Vibrationsgruppen signifikant erhöhten endostalen Kallusdichte sowie einer gegenüber der nichtvibrierten OVX-Gruppe signifikant erhöhten periostalen Kallusdichte und -dicke. Auch kortikaler und trabekulärer Knochen profitierten von der 70Hz-Vibration, was sich in der unter dieser Frequenz - zumindest hinsichtlich der Belastbarkeit - besten Kallusqualität widerspiegelte.
Die 35Hz-Vibration kann die Kallusbildung ebenfalls anregen und damit auch die biomechanischen Eigenschaften des Kallus (Steifheit) verbessern. Kallus und kortikaler Knochen werden durch 35 Hz aber schlechter stimuliert als durch alle anderen untersuchten Frequenzen. Die 50Hz-Vibration verbessert die biomechanischen Eigenschaften in ähnlicher Weise, sie stimuliert Kallus und Kortikalis dabei etwas besser als 35 Hz, aber deutlich schlechter als 70 Hz. Auch die 90Hz-Vibration hat einen stimulierenden Effekt auf Kallus, Kortikalis und trabekulären Knochen, insbesondere die Kallusstimulation ist aber wieder deutlich schlechter als unter der Frequenz von 70 Hz. Die 90Hz-Vibration hat zudem eine übermäßige Reizung des Kallus zur Folge, die sich in den schlechtesten biomechanischen Eigenschaften aller untersuchten Frequenzen manifestiert.
Als Synthese der mit den verschiedenen Untersuchungsverfahren dieser Arbeit gewonnenen Ergebnisse kann eine Überlegenheit der Vibrationsfrequenz von 70 Hz für die Stimulation der Frakturheilung bei Osteoporose festgestellt werden. Diese Ergebnisse am Rattentiermodell sollten - vor Beginn einer klinischen Studie - am Großtiermodell verifiziert werden.
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Vorwerk, Elena. "Die therapeutischen Effekte von Estradiol, Dihydrotestosteron, Genistein und Equol auf den osteoporotischen Knochen der orchidektomierten männlichen Sprague-Dawley-Ratte." Doctoral thesis, 2010. http://hdl.handle.net/11858/00-1735-0000-0006-B16E-C.
Testo completoCapitoli di libri sul tema "Osteoporosis Tibia Rats"
1
"Open Fragility Fractures." In Standards for the Management of Open Fractures, edited by Simon Eccles, Bob Handley, Umraz Khan, Iain McFadyen, Jagdeep Nanchahal, and Selvadurai Nayagam. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198849360.003.0015.
Testo completoAbstract (sommario):
Open fractures of the lower limb are increasingly common in older patients in whom surgical reconstruction is complicated by poor-quality bone and soft tissues, and whose complex healthcare needs are exacerbated by frailty and the presence of multiple co-morbidities. These challenges are likely to increase as the Office for National Statistics predicts that the number of people aged 75 and over in the UK will rise from 5.2 million in 2014 to 9.9 million in 2039. The majority of open fragility fractures of the lower limb occur in the tibia and ankle of older women as a result of a fall from standing. Despite the low-energy mechanism there is a high incidence of Gustilo–Anderson III (predominantly IIIA) injuries. This reflects the frailty of this patient group and the combined effects that osteoporosis and skin ageing have upon the quality of the bone and integrity of the surrounding soft tissue envelope. Reconstruction is complicated by higher rates of malunion, non-union, necessity for amputation, and mortality as compared with younger patients with similar injuries. These patients may have complex ongoing healthcare needs requiring additional support that influence safe delivery of the established ‘best practice’ surgical interventions.
Atti di convegni sul tema "Osteoporosis Tibia Rats"
1
Ciani, Cesare, Paula A. Ramirez Marin, Stephen B. Doty, and Susannah P. Fritton. "Estrogen Depletion Increases Osteocyte Canalicular Diameter in Cortical and Cancellous Bone of the Rat Proximal Tibia." In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-205382.
Testo completoAbstract (sommario):
Estrogen depletion has been shown to cause bone loss in the proximal metaphysis of the rat tibia [1,2]. A decrease in bone volume fraction is frequently reported, yet there is little analysis in the literature related to changes in microporosities during osteoporosis. Our recent work quantifying microporosity changes due to estrogen depletion has shown an increase in the lacunar-canalicular porosity surrounding osteocytes in the proximal metaphysis of the rat tibia [3].
2
Xiangdong Ma, Jun Wang, and Xing Ma. "Full-scale 3D reconstruction contributes to micro-CT stereological assessments of osteoporotic proximal tibial cancellous bone in rats." In 2010 International Conference on Computer Design and Applications (ICCDA 2010). IEEE, 2010. http://dx.doi.org/10.1109/iccda.2010.5541490.
Testo completo