Effects of local osteoprotegerin gene transfection on orthodontic root resorption during retention: an in vivo micro-CT analysis

Goniopora was hydrothermally converted to coralline hydroxyapatite (CHA) and incorporated with Sr (Sr-CHA). The pore size of Goniopora was in the range of 40–300 μm with a porosity of about 68%. Surface morphologies of the coral were modified to flake-like hydroxyapatite structures on CHA and the addition of Sr detected on Sr-CHA as confirmed by SEM and EDX. As the first report of incorporating Sr into coral, about 6%–14% Sr was detected on Sr-CHA. The compressive strengths of CHA and Sr-CHA were not compromised due to the hydrothermal treatments. Sr-CHA was studied in vitro using MC3T3-E1 cells and in vivo with an ovariectomized rat model. The proliferation of MC3T3-E1 cells was significantly promoted by Sr-CHA as compared to CHA. Moreover, higher scaffold volume retention (+40%) was reported on the micro-CT analysis of the Sr-CHA scaffold. The results suggest that the incorporation of Sr in CHA can further enhance the osteoconductivity and osteoinductivity of corals. Strontium has been suggested to stimulate bone growth and inhibit bone resorption. In this study, we have successfully incorporated Sr into CHA with the natural porous structure remained and explored the idea of Sr-CHA as a potential scaffolding material for bone regeneration.

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Constant Strain Rate and Peri-Implant Bone Modeling: An In Vivo Longitudinal Micro-CT Analysis

Clinical Implant Dentistry and Related Research ◽

10.1111/j.1708-8208.2011.00375.x ◽

2011 ◽

Vol 15 (3) ◽

pp. 358-366 ◽

Cited By ~ 1

Author(s):

Els De Smet ◽

Siegfried V. N. Jaecques ◽

Martine Wevers ◽

Jos Vander Sloten ◽

Ignace E. Naert

Keyword(s):

Strain Rate ◽

Constant Strain Rate ◽

Bone Modeling ◽

Micro Ct ◽

Ct Analysis

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A micro-CT analysis of murine lung recruitment in bleomycin-induced lung injury

Journal of Applied Physiology ◽

10.1152/japplphysiol.00980.2007 ◽

2008 ◽

Vol 105 (2) ◽

pp. 669-677 ◽

Cited By ~ 12

Author(s):

Scott Shofer ◽

Cristian Badea ◽

Yi Qi ◽

Erin Potts ◽

W. Michael Foster ◽

...

Keyword(s):

Lung Injury ◽

Lung Recruitment ◽

Normal Lung ◽

Micro Ct ◽

Thoracic Imaging ◽

Ct Analysis ◽

High Resolution Images ◽

X Ray Computed ◽

Parenchymal Injury

The effects of lung injury on pulmonary recruitment are incompletely understood. X-ray computed tomography (CT) has been a valuable tool in assessing changes in recruitment during lung injury. With the development of preclinical CT scanners designed for thoracic imaging in rodents, it is possible to acquire high-resolution images during the evolution of a pulmonary injury in living mice. We quantitatively assessed changes in recruitment caused by intratracheal bleomycin at 1 and 3 wk after administration using micro-CT in 129S6/SvEvTac mice. Twenty female mice were administered 2.5 U of bleomycin or saline and imaged with micro-CT at end inspiration and end expiration. Mice were extubated and allowed to recover from anesthesia and then reevaluated in vivo for quasi-static compliance measurements, followed by harvesting of the lungs for collagen analysis and histology. CT images were converted to histograms and analyzed for mean lung attenuation (MLA). MLA was significantly greater for bleomycin-exposed mice at week 1 for both inspiration ( P < 0.0047) and exhalation ( P < 0.0377) but was not significantly different for week 3 bleomycin-exposed mice. However, week 3 bleomycin-exposed mice did display significant increases in MLA shift from expiration to inspiration compared with either group of control mice ( P < 0.005), suggesting increased lung recruitment at this time point. Week 1 bleomycin-exposed mice displayed normal shifts in MLA with inspiration, suggesting normal lung recruitment despite significant radiographic and histological changes. Lung alveolar recruitment is preserved in a mouse model of bleomycin-induced parenchymal injury despite significant changes in radiographic and physiological parameters.

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The Influence of Electron Beam Sterilization on In Vivo Degradation of β-TCP/PCL of Different Composite Ratios for Bone Tissue Engineering

Micromachines ◽

10.3390/mi11030273 ◽

2020 ◽

Vol 11 (3) ◽

pp. 273 ◽

Cited By ~ 1

Author(s):

Jin-Ho Kang ◽

Janelle Kaneda ◽

Jae-Gon Jang ◽

Kumaresan Sakthiabirami ◽

Elaine Lui ◽

...

Keyword(s):

Electron Beam ◽

Volume Reduction ◽

Micro Ct ◽

Micro Computed Tomography ◽

Average Volume ◽

Volume Changes ◽

Significant Difference ◽

Ct Analysis ◽

Time Point

We evaluated the effect of electron beam (E-beam) sterilization (25 kGy, ISO 11137) on the degradation of β-tricalcium phosphate/polycaprolactone (β-TCP/PCL) composite filaments of various ratios (0:100, 20:80, 40:60, and 60:40 TCP:PCL by mass) in a rat subcutaneous model for 24 weeks. Volumes of the samples before implantation and after explantation were measured using micro-computed tomography (micro-CT). The filament volume changes before sacrifice were also measured using a live micro-CT. In our micro-CT analyses, there was no significant difference in volume change between the E-beam treated groups and non-E-beam treated groups of the same β-TCP to PCL ratios, except for the 0% β-TCP group. However, the average volume reduction differences between the E-beam and non-E-beam groups in the same-ratio samples were 0.76% (0% TCP), 3.30% (20% TCP), 4.65% (40% TCP), and 3.67% (60% TCP). The E-beam samples generally had more volume reduction in all experimental groups. Therefore, E-beam treatment may accelerate degradation. In our live micro-CT analyses, most volume reduction arose in the first four weeks after implantation and slowed between 4 and 20 weeks in all groups. E-beam groups showed greater volume reduction at every time point, which is consistent with the results by micro-CT analysis. Histology results suggest the biocompatibility of TCP/PCL composite filaments.

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Non-Viral Vectors for Gene Delivery

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681208666180110154233 ◽

2018 ◽

Vol 9 (1) ◽

pp. 4-11 ◽

Cited By ~ 5

Author(s):

Aparna Bansal ◽

Himanshu

Keyword(s):

Gene Therapy ◽

Viral Vectors ◽

Transfection Efficiency ◽

Gene Transfection ◽

Expression System ◽

Target Cells ◽

Specific Expression ◽

Naked Dna

Introduction: Gene therapy has emerged out as a promising therapeutic pave for the treatment of genetic and acquired diseases. Gene transfection into target cells using naked DNA is a simple and safe approach which has been further improved by combining vectors or gene carriers. Both viral and non-viral approaches have achieved a milestone to establish this technique, but non-viral approaches have attained a significant attention because of their favourable properties like less immunotoxicity and biosafety, easy to produce with versatile surface modifications, etc. Literature is rich in evidences which revealed that undoubtedly, non–viral vectors have acquired a unique place in gene therapy but still there are number of challenges which are to be overcome to increase their effectiveness and prove them ideal gene vectors. Conclusion: To date, tissue specific expression, long lasting gene expression system, enhanced gene transfection efficiency has been achieved with improvement in delivery methods using non-viral vectors. This review mainly summarizes the various physical and chemical methods for gene transfer in vitro and in vivo.

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Modelling the skeletal muscle injury recovery using in vivo contrast-enhanced micro-CT: a proof-of-concept study in a rat model

European Radiology Experimental ◽

10.1186/s41747-020-00163-4 ◽

2020 ◽

Vol 4 (1) ◽

Cited By ~ 1

Author(s):

Bruno Paun ◽

Daniel García Leon ◽

Alex Claveria Cabello ◽

Roso Mares Pages ◽

Elena de la Calle Vargas ◽

...

Keyword(s):

Skeletal Muscle ◽

Rat Model ◽

Muscle Injury ◽

Micro Ct ◽

Skeletal Muscle Injury ◽

Monitoring Time ◽

Contrast Enhanced Ct ◽

Contrast Enhanced ◽

Injury Recovery

Abstract Background Skeletal muscle injury characterisation during healing supports trauma prognosis. Given the potential interest of computed tomography (CT) in muscle diseases and lack of in vivo CT methodology to image skeletal muscle wound healing, we tracked skeletal muscle injury recovery using in vivo micro-CT in a rat model to obtain a predictive model. Methods Skeletal muscle injury was performed in 23 rats. Twenty animals were sorted into five groups to image lesion recovery at 2, 4, 7, 10, or 14 days after injury using contrast-enhanced micro-CT. Injury volumes were quantified using a semiautomatic image processing, and these values were used to build a prediction model. The remaining 3 rats were imaged at all monitoring time points as validation. Predictions were compared with Bland-Altman analysis. Results Optimal contrast agent dose was found to be 20 mL/kg injected at 400 μL/min. Injury volumes showed a decreasing tendency from day 0 (32.3 ± 12.0mm3, mean ± standard deviation) to day 2, 4, 7, 10, and 14 after injury (19.6 ± 12.6, 11.0 ± 6.7, 8.2 ± 7.7, 5.7 ± 3.9, and 4.5 ± 4.8 mm3, respectively). Groups with single monitoring time point did not yield significant differences with the validation group lesions. Further exponential model training with single follow-up data (R2 = 0.968) to predict injury recovery in the validation cohort gave a predictions root mean squared error of 6.8 ± 5.4 mm3. Further prediction analysis yielded a bias of 2.327. Conclusion Contrast-enhanced CT allowed in vivo tracking of skeletal muscle injury recovery in rat.

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