scholarly journals Micrometer-Sized Titanium Particles Induce Aseptic Loosening in Rabbit Knee

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Hao Xu ◽  
Cui-cui Guo ◽  
Zheng-yu Gao ◽  
Chang-yao Wang ◽  
Hai-ning Zhang ◽  
...  

Wear debris induced aseptic loosening is the leading cause of total knee arthroplasty (TKA) failure. The complex mechanism of aseptic loosening has been a major issue for introducing effective prevention and treatment methods, so a simplified yet efficient rabbit model was established to address this concern with the use of micrometer-sized titanium particles. 20 New Zealand white rabbits were selected and divided into two groups (control = 10, study = 10). A TKA surgery was then performed for each of them, with implantation of a titanium rod prosthesis which was coated evenly with micrometer-sized titanium in the study group and nothing in the control group, into right femoral medullary cavity. After 12 weeks, all the animals were euthanized and X-ray analyses, H&E staining, Goldner Masson trichrome staining, Von Kossa staining, PCR, and Western blotting of some specific mRNAs and proteins in the interface membrane tissues around the prosthesis were carried out. The implantation of a titanium rod prosthesis coated with 20 μm titanium particles into the femoral medullary cavity of rabbits caused continuous titanium particle stimulation around the prosthesis, effectively inducing osteolysis and aseptic loosening. Titanium particle-induced macrophages produce multiple inflammatory factors able to activate osteoclast differentiation through the OPG/RANKL/RANK signaling pathway, resulting in osteolysis while suppressing the function of osteoblasts and reducing bone ingrowth around the prosthesis. This model simulated the implantation and loosening process of an artificial prosthesis, which is an ideal etiological model to study the aseptic prosthetic loosening.

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Peng Wang ◽  
Guang-qian Shang ◽  
Shuai Xiang ◽  
Hai-ning Zhang ◽  
Ying-zhen Wang ◽  
...  

Abstract Background Revisions are mainly caused by wear debris-induced aseptic loosening. How to effectively suppress debris-induced periprosthetic osteolysis has become an urgent problem. Both zoledronic acid and teriparatide can increase the bone mass around prostheses and increase the stability of prostheses. A hypothesis was proposed: the combination of the two drugs may have a better treatment effect than the use of either drug alone. Methods We created a rabbit model to study the effect and mechanism of the combination of zoledronic acid and teriparatide in the treatment of aseptic loosening. Thirty-two adult male New Zealand white rabbits were selected and treated with TKA surgery, and a titanium rod prosthesis coated evenly with micrometre-sized titanium debris was implanted into the right femoral medullary cavity. All rabbits were randomized into four groups (control group = 8, zoledronic acid group = 8, teriparatide group = 8, and zoledronic acid + teriparatide group = 8). All the animals were sacrificed in the 12th week, and X-ray analyses, H&E staining, Goldner-Masson trichrome staining, von Kossa staining, and RT-PCR and Western blotting of the mRNA and protein of OCN, OPG, RANKL and TRAP5b in the interface membrane tissues around the prostheses were immediately carried out. Results The results shown that both zoledronic acid and teriparatide could inhibit debris-induced peri-prosthetic osteolysis and promote new bone formation. Zoledronic acid was more capable of inhibiting osteoclast activation and peri-prosthetic osteolysis, while teriparatide was more capable of promoting osteoblast function and peri-prosthetic bone integration. Conclusion This research confirmed that the combination of zoledronic acid and teriparatide could prevent and treat aseptic loosening of the prosthesis more effectively. However, the safety of this combination and the feasibility of long-term application have not been ensured, and the clinical application requires further experiments and clinical research support.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Claus Moseke ◽  
Katharina Wimmer ◽  
Markus Meininger ◽  
Julia Zerweck ◽  
Cornelia Wolf-Brandstetter ◽  
...  

AbstractTo develop implants with improved bone ingrowth, titanium substrates were coated with homogeneous and dense struvite (MgNH4PO4·6H2O) layers by means of electrochemically assisted deposition. Strontium nitrate was added to the coating electrolyte in various concentrations, in order to fabricate Sr-doped struvite coatings with Sr loading ranging from 10.6 to 115 μg/cm2. It was expected and observed that osteoclast activity surrounding the implant was inhibited. The cytocompatibility of the coatings and the effect of Sr-ions in different concentrations on osteoclast formation were analyzed in vitro. Osteoclast differentiation was elucidated on morphological, biochemical as well as on gene expression level. It could be shown that moderate concentrations of Sr2+ had an inhibitory effect on osteoclast formation, while the growth of osteoblastic cells was not negatively influenced compared to pure struvite surfaces. In summary, the electrochemically deposited Sr-doped struvite coatings are a promising approach to improve bone implant ingrowth.


Author(s):  
Hong Wang ◽  
Wenjuan Zhang ◽  
Jinren Liu ◽  
Junhong Gao ◽  
Le Fang ◽  
...  

Abstract Blast lung injury (BLI) is the major cause of death in explosion-derived shock waves; however, the mechanisms of BLI are not well understood. To identify the time-dependent manner of BLI, a model of lung injury of rats induced by shock waves was established by a fuel air explosive. The model was evaluated by hematoxylin and eosin staining and pathological score. The inflammation and oxidative stress of lung injury were also investigated. The pathological scores of rats’ lung injury at 2 h, 24 h, 3 days, and 7 days post-blast were 9.75±2.96, 13.00±1.85, 8.50±1.51, and 4.00±1.41, respectively, which were significantly increased compared with those in the control group (1.13±0.64; P<0.05). The respiratory frequency and pause were increased significantly, while minute expiratory volume, inspiratory time, and inspiratory peak flow rate were decreased in a time-dependent manner at 2 and 24 h post-blast compared with those in the control group. In addition, the expressions of inflammatory factors such as interleukin (IL)-6, IL-8, FosB, and NF-κB were increased significantly at 2 h and peaked at 24 h, which gradually decreased after 3 days and returned to normal in 2 weeks. The levels of total antioxidant capacity, total superoxide dismutase, and glutathione peroxidase were significantly decreased 24 h after the shock wave blast. Conversely, the malondialdehyde level reached the peak at 24 h. These results indicated that inflammatory and oxidative stress induced by shock waves changed significantly in a time-dependent manner, which may be the important factors and novel therapeutic targets for the treatment of BLI.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S213-S213
Author(s):  
Karen J Shaw ◽  
Charles D Giamberardino ◽  
Quinlyn A Soltow ◽  
Jennifer Tenor ◽  
Dena Toffaletti ◽  
...  

Abstract Background Cryptococcal meningitis (CM), caused primarily by Cryptococcus neoformans, is uniformly fatal if not treated. Treatment options are limited especially in resource-poor geographical regions, and mortality rates remain high despite current therapies. New oral treatment options are needed that demonstrate rapid reductions in CFU in CSF and brain tissue. APX2039 is a novel inhibitor of the fungal Gwt1 enzyme, which catalyzes an early step in glycosylphosphatidyl inositol (GPI) anchor biosynthesis. It is highly active against both C. neoformans and C. gattii and has previously demonstrated significant efficacy in a mouse delayed-treatment model of CM. CSF Fungal Burden in Rabbits Methods Male New Zealand White rabbits were inoculated with C. neoformans H99 (1.4 ×106 CFU) directly into the cisterna magna. Rabbits were immunosuppressed with cortisone acetate at 7.5 mg/kg (i.m.), starting on Day -1 relative to inoculation and then administered drug daily throughout the 14-day experimental period. Treatment was initiated on Day 2 postinfection and continued through Day 14 consisting of: 50 mg/kg APX2039 PO (BID), 80 mg/kg fluconazole (FLU) PO (QD), c) 1 mg/kg amphotericin B deoxycholate (AMB) IV (QD); and vehicle control. CSF was removed via an intracisternal tap on Days 2, 7, 10 and 14 post-infection and CFU/ml was assessed. Animals were sacrificed on Day 14 and CFU/g brain tissue was assessed. Results APX2039 demonstrated rapid reduction in CFU in both CSF and brain tissue. The range in CFU values in rabbit CSF is shown (Figure). Reductions in CFU were statistically different from the control group for all treatment groups. APX2039 was also different from both FLU and AMB and resulted in sterilization in CSF by Day 10. Brain harvested on Day 14 demonstrated a reduction in CFU/g tissue vs control of 1.8 log10 and 3.4 log10 for FLU and AMB, respectively, while a > 6 log10 reduction (tissue sterilization) was observed for APX2039. Conclusion APX2039 demonstrated potent efficacy in a rabbit model of CM. The more rapid clearance in CSF than either AMB or FLU, as well as > 6 log10 reduction in brain CFU highlights the unique properties of this drug, warranting further investigation of this molecule for the treatment of CM. Disclosures Karen J. Shaw, PhD, Amplyx (Consultant)Forge Therapeutics (Consultant) Charles D. Giamberardino, Jr., MR, Box (Shareholder) John R. Perfect, MD, amplyx (Grant/Research Support)astellas (Grant/Research Support)astellas (Grant/Research Support)


2021 ◽  
pp. 153537022110271
Author(s):  
Yuanyuan Jia ◽  
Liuqin Xie ◽  
Zhenglong Tang ◽  
Dongxiang Wang ◽  
Yun Hu ◽  
...  

After high fractures of the mandibular condyle, the insufficient blood supply to the condyle often leads to poor bone and cartilage repair ability and poor clinical outcome. Parathyroid hormone (PTH) can promote the bone formation and mineralization of mandibular fracture, but its effects on cartilage healing after the free reduction and internal fixation of high fractures of the mandibular condyle are unknown. In this study, a rabbit model of free reduction and internal fixation of high fractures of the mandibular condyle was established, and the effects and mechanisms of PTH on condylar cartilage healing were explored. Forty-eight specific-pathogen-free (SPF) grade rabbits were randomly divided into two groups. In the experimental group, PTH was injected subcutaneously at 20 µg/kg (PTH (1–34)) every other day, and in the control group, PTH was replaced with 1 ml saline. The healing cartilages were assessed at postoperative days 7, 14, 21, and 28. Observation of gross specimens, hematoxylin eosin staining and Safranin O/fast green staining found that every-other-day subcutaneous injection of PTH at 20 µg/kg promoted healing of condylar cartilage and subchondral osteogenesis in the fracture site. Immunohistochemistry and polymerase chain reaction showed that PTH significantly upregulated the chondrogenic genes Sox9 and Col2a1 in the cartilage fracture site within 7–21 postoperative days in the experimental group than those in the control group, while it downregulated the cartilage inflammation gene matrix metalloproteinase-13 and chondrocyte terminal differentiation gene ColX. In summary, exogenous PTH can stimulate the formation of cartilage matrix by triggering Sox9 expression at the early stage of cartilage healing, and it provides a potential therapeutic protocol for high fractures of the mandibular condyle.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
J. Peng ◽  
C. Y. Le ◽  
B. Xia ◽  
J. W. Wang ◽  
J. J. Liu ◽  
...  

Abstract Background Activating transcription factor 3 (ATF3) is an early response gene that is activated in response to atherosclerotic stimulation and may be an important factor in inhibiting the progression of atherosclerosis. In this study, we directly measured the expression of ATF3 and inflammatory factors in human coronary atherosclerotic plaques to examine the relationship between ATF3 expression, inflammation and structural stability in human coronary atherosclerotic plaques. Methods A total of 68 coronary artery specimens were collected from the autopsy group, including 36 cases of sudden death from coronary heart disease (SCD group) and 32 cases of acute death caused by mechanical injury with coronary atherosclerosis (CHD group). Twenty-two patients who had no coronary heart disease were collected as the control group (Con group). The histological structure of the coronary artery was observed under a light microscope after routine HE staining, and the intimal and lesion thicknesses, thickness of the fibrous cap, thickness of necrosis core, degree of lumen stenosis were assessed by image analysis software. Western blotting and immunohistochemistry were used to measure the expression and distribution of ATF3, inflammatory factors (CD45, IL-1β, TNF-α) and matrix metalloproteinase-9 (MMP-9) and vascular cell adhesion molecule 1 (VCAM1) in the coronary artery. The Pearson correlation coefficient was used to analyse the correlation between ATF3 protein expression and inflammatory factors and between ATF3 protein expression and structure-related indexes in the lesion group. Results Compared with those in the control group, the intima and necrotic core in the coronary artery were thickened, the fibrous cap became thin and the degree of vascular stenosis was increased in the lesion group, while the intima and necrotic core became thicker and the fibrous cap became thinner in the SCD group than in the CHD group (P < 0.05). There was no or low expression of ATF3, inflammatory factors, VCAM1 and MMP-9 in the control group, and the expression of inflammatory factors, VCAM1 and MMP-9 in the SCD group was higher than that in CHD group, while the expression of ATF3 in the SCD group was significantly lower than that in CHD group (P < 0.05). In the lesion group, the expression of ATF3 was negatively correlated with intimal and necrotic focus thickness, positively correlated with fibrous cap thickness (P < 0.01), and negatively correlated with inflammatory factors, VCAM1 and MMP-9 (P < 0.01). Conclusions The expression of ATF3 may be related to the progression and stability of atherosclerotic plaques, and may affect the structural stability of atherosclerotic plaques by regulating the inflammatory response, thus participating in the regulation of atherosclerotic progression.


Cardiology ◽  
2016 ◽  
Vol 135 (4) ◽  
pp. 221-227 ◽  
Author(s):  
Shao-Ling Yang ◽  
Ke-Qiang Tang ◽  
Jun-Jia Tao ◽  
Ai-Hong Wan ◽  
Yan-Duan Lin ◽  
...  

Objectives: We aimed to evaluate whether ultrasound (US) and microbubble-mediated delivery of Cluster of Differentiation 151 (CD151) could enhance the therapeutic effects of CD151 on myocardial infarction (MI). Methods: A rabbit model of MI was established by a modified Fujita method. Then, 50 MI rabbits were randomly divided into 5 groups, including G1 (CD151 plasmid and physiological saline in the presence of US); G2 (CD151 and Sonovue in the presence of US); G3 (CD151 and Sonovue in the absence of US); G4 (Sonovue in the absence of US), and a control group (physiological saline in the absence of US). After 14 days of treatment, the expression of CD151 was detected by Western blot. Besides, vessel density of peri-infarcted myocardium was measured by immunohistochemistry, and cardiac function was analyzed by echocardiography. Results: The rabbit model of MI was established successfully. CD151 injection increased the expression of CD151 and microvessel density in the myocardium of MI rabbits. Heart function was significantly improved by CD151, which exhibited increased left ventricular ejection fraction, left ventricular fractional shortening and a reduced Tei index. Besides, US Sonovue significantly increased the expression efficiency of CD151. Conclusion: US microbubble was an effective vector for CD151 delivery. CD151 might be an effective therapeutic target for MI.


2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Antonio Scarano ◽  
Ezio Crocetta ◽  
Alessandro Quaranta ◽  
Felice Lorusso

Background. Pure titanium continues to be the first choice for dental implants and represents the gold standard for their biocompatibility and physical and mechanical characteristics, while the titanium alloy (Ti6Al4V) has good mechanical properties. The surface structure of the titanium oxide layer formation on the surface influences and improves the bone response around dental implants. Purpose. The purpose of this study is to evaluate the influence of a thermal treatment of Ti6Al4V implant surfaces and the bone healing response in a rabbit model. Methods. Altogether sixteen implants with same design were inserted into the distal femoral metaphysis. A screw (13 mm long, 4 mm in diameter) was inserted in an implant bed. Each rabbit received two implants, one in the left femur and one in the right femur. The samples were histologically and histomorphometrically evaluated at 8 weeks. Results. A statistically significant difference (p = 0.000034) was present histologically in the percentages of bone-implant contact (BIC) between the test group (BIC = 69.25±4.49%.) and control group (BIC = 56.25 ± 4.8%) by one-way analysis of variance (ANOVA). Significance was set at p ≤ 0.05. Conclusions. The outcome of the present study indicates a novel approach to improving bone healing around titanium implants.


2021 ◽  
Vol 11 (9) ◽  
pp. 1838-1843
Author(s):  
Xiaohong Zhou ◽  
Xuzhong Hao ◽  
Feifei He

To investigate whether exosomes (exo) derived from human umbilical cord mesenchymal stem cells (huMSCs) and microRNA (miRNA)-342 have a protective effect on severe acute pancreatitis (SAP). Human umbilical cord blood was collected to extract huMSC-exo. With sham-operated mice as control group (n = 10), the other mice were induced to SAP model (n = 20), while 10 of the SAP mice received treatment with huMSC-exo. ELISA was performed to determine amylase and TAP level as well as inflammatory factors and HE staining to evaluate pathological changes of pancreatic tissue. The expression of miR-342 and Shh, Ptchl, and Smo in the Hh signal pathway was detected using RT-qPCR. The expression of miR-342 and the mRNA expression of Shh, Ptchl, and Smo was higher than that in model group (p < 0.05). The level of serum amylase, trypsinogen, and IFN-γ,Fasl, and IL-6 was upregulated in pancreas tissues of SAP mice relative to healthy mice, but their levels were decreased upon treatment with huMSC-exo and slightly higher than those of the control group, just not significantly. Collectively, the huMSC-exo may activate the Hh signaling pathway by regulating the expression of miR-342 increasing the expression of Shh, Ptchl, and Smo, and thereby healing of damaged pancreatic tissues in SAP.


2022 ◽  
Vol 12 (5) ◽  
pp. 1034-1039
Author(s):  
Xiaoxiang Wang ◽  
Lan Yu ◽  
Xing Xiong ◽  
Yao Chen ◽  
Bo Men

Bone marrow mesenchymal stem cells (BMSCs) are capable of multipolar differentiation and repairing injured tissues. Herein, we aimed to investigate the mechanism by how BMSCs modulate the apoptotic pathway in the acute pancreatitis (AP). In this study, primary BMSCs were cultured and administrated into 10 AP mice while 10 healthy mice were taken as a blank group and 10 AP mice as a control group. The mouse pancreatic tissues were assessed by HE staining and evaluated by pancreatitis score and serum amylase detection. Level of inflammatory factors CRP and TNF-α was measured by ELISA and PIPK1, PIPK3, MLKL and Caspase-8 expression was detected by RT-qPCR and Western blot. The pancreatitis score (7.29±1.36) and the serum amylase score of (453.66±103.67) mu/ml of BMSCs group was significantly higher than that of control group, indicating increased tissue repair after BMSCs treatment. BMSCs group exhibited a higher level of CRP (711.01±115.31) and TNF-α (132.81±22.13) in serum compared to control group (p < 0.05). PIPK1, PIPK3, and MLKL expression in BMSCs group decreased (p < 0.05) whereas Caspase-8 was increased (p < 0.05). On the other hand, BMSCs group presented upregulated PIPK1, PIPK3, and MLKL (p < 0.05) and downregulated Caspase-8 (p < 0.05). In conclusion, BMSCs regulate cell apoptosis by upregulating Caspase-8 expression, and downregulating PIPK1, PIPK3 and MLKL level, thereby alleviating the inflammation in AP.


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