BONY TRABECULAR MICRO-STRUCTURE AND POROSITY WITH AGE IN YOUNG RABBIT’S FEMUR: IN-VIVO STUDY

2016 ◽  
Vol 78 (6-8) ◽  
Author(s):  
Khairunnisa Abd Manan ◽  
Sulaiman Md Dom
Keyword(s):  
Total Porosity ◽  
Average Intensity ◽  
Mechanical Index ◽  
Micro Computed Tomography ◽  
Bone Morphology ◽  
Trabecular Thickness ◽  
Trabecular Microstructure ◽  
Significant Difference ◽  
Ct Analysis

The established of micro computed tomography (micro-CT) analysis software make it compatible to use to determine abnormality of bone morphology. This study investigated 90 new rabbits for bony trabecular microstructure and porosity after their dams were exposed to ultrasound at the second stage of pregnancy (duration - 90 minutes; frequency - 7.09 MHz; spatial peak temporal average intensity (SPTA) - 49.4 W/cm2; power - 56 W; thermal index (TI) - 0.2; mechanical index (MI) - 1.0). A femur of five groups of litters (n = 18 litters per group): 1, 2, 3, 4 and 5 month-old was excised and scanned using SkyscanTM 1176. For total porosity, a significant difference was shown in at two month-old group (p = 0.017). A significant difference was also shown in bony trabecular thickness for three month-old group (p < 0.05). For trabecular separation, there was a significant difference at four month-old group (p = 0.040). This study suggested that there might be some significant differences in bony trabecular structure and total porosity with ages. This may be due to heat created by ultrasound exposure, which can apply effect to bone morphology. To determine whether the findings are applicable to human, clinical trials should be carried out in the future.

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

Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 273 ◽  
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.

Controlled Cyclic Compression of an Open Tibial Fracture Using an External Fixator Affects Fracture Healing in Mice

2015 ◽  
Vol 137 (5) ◽  
Author(s):  
Jennifer A. Currey ◽  
Megan Mancuso ◽  
Sylvie Kalikoff ◽  
Erin Miller ◽  
Sean Day
Keyword(s):  
Fracture Healing ◽  
Mechanical Stimulation ◽  
External Fixator ◽  
Qualitative Assessment ◽  
Control Group ◽  
External Fixators ◽  
Tibial Osteotomy ◽  
Micro Computed Tomography ◽  
Trabecular Thickness ◽  
Significant Difference

Fractures resulting in impaired healing can be treated with mechanical stimulation via external fixators. To examine the effect of mechanical stimulation on fracture healing, we developed an external fixator for use in a mouse model. A 0.5 mm tibial osteotomy was stabilized with the external fixator in C57BL/6 mice. Osteotomies in the treatment group (nt = 41) were subjected to daily sessions of 150 μm of controlled displacement with the aim to create a more mineralized callus at 21 days compared with the control group (nc = 39). Qualitative assessment of the histology found no notable difference in healing patterns between groups at 7, 12, 17, and 21 days. At 21 days, micro-computed tomography (CT) analysis showed that the control group had a significantly higher bone volume (BV) fraction and trabecular number compared with treatment; however there was no significant difference in the total volume (TV) of the callus or trabecular thickness between groups. In summary, the external fixator was used with a motion application system to apply controlled displacement to a healing fracture; however, this treatment did not result in a more mineralized callus at 21 days.

scholarly journals Serum amyloid A 1 protein isoforms induce Rheumatoid Arthritis

2020 ◽  
Author(s):  
Elaine Lai-Han Leung ◽  
Huan-Ling Lai ◽  
Run-Ze Li ◽  
Hu-Dan Pan ◽  
Ze-Bo Jiang ◽  
...  
Keyword(s):  
Early Diagnosis ◽  
Bone Destruction ◽  
Joint Inflammation ◽  
Protein Isoforms ◽  
Knee Joints ◽  
Micro Computed Tomography ◽  
Bone Morphology ◽  
Amyloid A ◽  
Severity Prediction ◽  
Ct Analysis

Abstract Background: SAA1 in RA pathogenesis and its complications remains unknown, making early diagnosis and risk prevention difficult. This study is to determine the pathogenetic mechanisms of three different SAA1 protein isoforms in RA progression. Methods: We modified an experimental adenovirus infection protocol in order to successfully introduce SAA1.2, SAA1.3, SAA1.5 gene alleles into the rear knee joints of C57BL/6 mice. Micro-computed tomography (micro-CT) analysis was applied to determine changes in bone morphology and density. Immunohistochemistry (IHC), flow cytometry, ELISA and real-time PCR were used to investigate disease progression and cytokine alterations in the course of adenoviral SAA-induced knee joint inflammation and bone destruction. Results: The pathogenetic functions of SAA1.2, SAA1.3 and SAA1.5 protein isoforms in promoting the initiation and progression of RA were determined. We established that SAA1.2 was the most aggressive factor in RA induction and progression. Mechanistically, we found that the arthritis-inducing effect of SAA1.2 transcription in the knee joints and mutant SAA1 protein secretion in blood results in stimulation of immune responses, leading to CD8+ T cell and pro-inflammatory cytokine elevation, with subsequent synovial inflammation and bone destruction. Conclusions: These findings indicate that SAA1 protein isoforms, particularly SAA1.2, play a significant role in the induction and progression of RA and may have potential value in the early diagnosis and severity prediction for RA.

scholarly journals Efficacy of sonothrombolysis using acoustically activated perflutren nanodroplets versus perflutren microbubbles

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S El Kadi ◽  
L Qian ◽  
P Zeng ◽  
J Lof ◽  
E Stolze ◽  
...  
Keyword(s):  
Vascular System ◽  
Single Pulse ◽  
Treated Group ◽  
In Vivo Studies ◽  
Funding Source ◽  
Mechanical Index ◽  
Liquid Droplets ◽  
Significant Difference ◽  
And Control

Abstract Background The use of intermittent high mechanical index (HMI) ultrasound impulses in combination with intravenously administered microbubbles (MB) has been shown to dissolve arterial and microvascular thrombi. The recent development of liquid droplets with nanoscale diameter from commercially available microbubbles may optimize thrombus permeation and subsequent thrombus dissolution. Methods Thrombi were formed from fresh porcine arterial whole blood mixed with thrombin, and placed in a vascular system mimicking branching epicardial coronary circulation (Figure 1A) at 37 Celsius and flow rate. A diagnostic ultrasound system with a tissue mimicking phantom was placed on top of the thrombus to simulate transthoracic echocardiography. Thrombus treatment consisted of a 10-minute infusion of either diluted nanodroplets (ND) or MB (same concentration) with intermittent HMI fundamental multipulse (3 usec pulse duration; FUS) or single pulse harmonic (HUS) impulses. All treatments were randomized and compared with HMI impulses alone. Efficacy was evaluated by percentage thrombus dissolution (%TD). Transmission electron microscopy (TEM) of residual thrombi after treatment was performed to examine for droplet permeation and resultant formed microbubble size. Results A relatively monodisperse nanodroplets size distribution was formed from microbubble cooled compression (mean diameter was 147±54 nm). A total of 60 porcine arterial thrombi were tested, 20 in each MB and ND treated group (20 control). Overall, there was a significant difference in %TD between ND treated thrombi (combining HUS and FUS HMI treated groups) versus MB treated thrombi and control (p&lt;0.0001 and p=0.02, respectively; ANOVA, Figure 1B). The highest %TD was seen in the FUS HMI treated ND group (mean 51±17%; Figure 1B). TEM of the DND treated group demonstrated significant expansion (diameters of 6 microns; Figure 1 C) of acoustically activated droplets embedded within the thrombi. Conclusion ND in combination with intermittent HMI ultrasound resulted in significantly greater thrombolysis compared to MB. In-vivo studies on nanodroplet mediated sonothrombolysis for vascular and microvascular thrombi should be performed with this modification of a commercially available microbubble. Figure 1 Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Theodore F. Hubbard Foundation

scholarly journals Small-sized magnesium cylinders influence subchondral bone quality in osteoarthritic rabbits – an in vivo pilot study

2021 ◽  
Vol 42 ◽  
pp. 179-195
Author(s):  
N Angrisani ◽  
◽  
R Willumeit-Römer ◽  
H Windhagen ◽  
B Mavila Chathoth ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Bone Quality ◽  
Subchondral Bone ◽  
Histological Evaluation ◽  
Micro Computed Tomography ◽  
Significant Difference ◽  
Group A ◽  
Drill Holes

No optimal therapy exists to stop or cure chondral degeneration in osteoarthritis (OA). While the pathogenesis is unclear, there is consensus on the etiological involvement of both articular cartilage and subchondral bone. Compared to original bone, the substance of sclerotic bone is mechanically less solid. The osteoproliferative effect of Mg has been shown repeatedly during development of Mg-based osteosynthesis implants. The aim of the present study was to examine the influence of implanted high-purity Mg cylinders on subchondral bone quality in a rabbit OA model. 10 New Zealand White rabbits received into the knee either 20 empty drill holes or 20 drill holes, which were additionally filled with one Mg cylinder each. Follow-up was at 8 weeks. Micro-computed tomography (µCT) was performed. After euthanasia, cartilage condition was determined, bone samples were collected and processed for histological evaluation and elemental imaging by micro-X-ray fluorescence spectrometry (µXRF). Articular cartilage collected post-mortem showed different stages of lesions, from mild alterations up to exposed subchondral bone, which tended to be slightly lower in animals with implanted Mg cylinders. µCT showed significantly increased bone volume in the Mg group. Also, histological evaluation revealed distinct differences. While right, operated limbs did not show any significant difference, left, non-operated controls showed significantly less changes in articular cartilage in the Mg group. A distinct influence of implanted cylinders of pure Mg on subchondral bone of osteoarthritic rabbits was shown. Subsequent evaluations, including other time points and alternative alloys, will show if this could alter OA progression.

scholarly journals Micro-computed tomography and mechanical evaluation of trabecular bone structure in osteopenic and osteoporotic fractures

2017 ◽  
Vol 25 (1) ◽  
pp. 230949901769271 ◽  
Author(s):  
Fırat Ozan ◽  
Mahmut Pekedis ◽  
Şemmi Koyuncu ◽  
Taşkın Altay ◽  
Hasan Yıldız ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Bone Structure ◽  
Structural Parameters ◽  
Osteoporotic Fractures ◽  
Biomechanical Properties ◽  
Compression Tests ◽  
Micro Computed Tomography ◽  
Mineral Density ◽  
Trabecular Thickness ◽  
Significant Difference

Purpose: Osteopenia and osteoporosis are the two most common musculoskeletal disorders in the elderly population. We determined whether osteopenic and osteoporotic patients with fractures exhibit differences in trabecular morphology and biomechanical properties of bone. Methods: Fourteen osteopenic patients and 28 osteoporotic patients with hip fractures who underwent hemiarthroplasty for proximal femoral fractures caused by low-energy injury were included. Bone mineral density (BMD) measurements were performed. Compression tests and high-resolution micro-computed tomography were used to assess cancellous bone samples obtained from the principal compressive region of the femoral head. Results: The BMD values were lower in the osteoporotic patients than in the osteopenic patients ( p < 0.05). There was a significant difference in the yield stress values between the groups ( p < 0.05). However, no significant differences in the strain energy density, stiffness and Young’s modulus were observed between the groups ( p > 0.05). The mean maximum stress was significantly higher in the osteoporotic patients than in the osteopenic patients ( p < 0.05). Although structural parameters, including bone volume (BV), BV fraction, trabecular thickness, trabecular connectivity density and trabecular number, were higher in the osteopenic patients, the differences were not significant ( p > 0.05). Trabecular separation values were significantly higher in the osteoporotic patients ( p < 0.05). Conclusion: Our results showed that the trabecular morphology and biomechanical properties of bone were not significantly different between osteopenic and osteoporotic patients in terms of some parameters.

scholarly journals Insight into Bone-Derived Biological Apatite: Ultrastructure and Effect of Thermal Treatment

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Quan Liu ◽  
Haobo Pan ◽  
Zhuofan Chen ◽  
Jukka Pekka Matinlinna
Keyword(s):  
Thermal Treatment ◽  
Degree Of Crystallinity ◽  
Spongy Bone ◽  
Mineral Density ◽  
Trabecular Thickness ◽  
Physiochemical Properties ◽  
Significant Difference ◽  
Biological Apatite ◽  
Vertebral Bodies

Objectives. This study aims at examining the ultrastructure of bone-derived biological apatite (BAp) from a series of small vertebrates and the effect of thermal treatment on its physiochemical properties.Materials and Methods. Femurs/fin rays and vertebral bodies of 5 kinds of small vertebrates were firstly analyzed with X-ray microtomography. Subsequently, BAp was obtained with thermal treatment and low power plasma ashing, respectively. The properties of BAp, including morphology, functional groups, and crystal characteristics were then analyzed.Results. The bones of grouper and hairtail were mainly composed of condensed bone. Spongy bone showed different distribution in the bones from frog, rat, and pigeon. No significant difference was found in bone mineral density of condensed bone and trabecular thickness of spongy bone. Only platelet-like crystals were observed for BAp obtained by plasma ashing, while rod-like and irregular crystals were both harvested from the bones treated by sintering. A much higher degree of crystallinity and larger crystal size but a lower content of carbonate were detected in the latter.Conclusion. Platelet-like BAp is the common inorganic component of vertebrate bones. BAp distributing in condensed and spongy bone may exhibit differing thermal reactivity. Thermal treatment may alter BAp’sin vivostructure and composition.

MORPHOMETRIC BRAIN MEASUREMENT OF PRENATAL ULTRASOUND-INDUCED RABBIT FETUS USING MICRO-COMPUTED TOMOGRAPHY (MICRO-CT)

2016 ◽  
Vol 78 (6-7) ◽  
Author(s):  
Farah W. A. Zaiki ◽  
S. M. Dom
Keyword(s):  
Computed Tomography ◽  
Neuronal Development ◽  
Brain Volume ◽  
Fetal Brain ◽  
Prenatal Ultrasound ◽  
Average Intensity ◽  
Mechanical Index ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
The Brain

Prenatal ultrasound is widely used and became an integral part of the clinical practice, particularly in obstetrics and gynecology. However, the advances in the capability of ultrasound equipment nowadays, trigger a greater image processing power, hence might as well increase the fetal exposure. Hence premises the morphometric brain measurement to be assessed in this study as an evidence of the ultrasound interruptions during the fetal neuronal development. This research randomly analyzed a total of 18 ultrasound-induced rabbit fetuses for fetal brain volume and surface after being exposed prenatally to the ultrasound exposure (duration=60 minutes; frequency = 7.09 MHz; spatial peak temporal average intensity (ISPTA) = 49.4 W/cm2; power = 56.0 W; thermal index (TI) = 0.2; mechanical index (MI) = 1.0). The fetuses were analyzed for morphometric brain measurement of brain volume and surface using Skyscan™ 1176 Micro-computed Tomography (Micro-CT). There were significant differences in the measurement of brain volume and surface at the 2nd and 3rd stage of gestation (P < 0.05). Results suggested that there are significant differences in the brain volume and surface between the controls and the 2nd and 3rd stage of gestation. There are also a significant reduction in the brain volume and surface in the exposed groups at all stages of gestation (P < 0.05). 

Surgeon Ability to Appropriately Address the Calcified Cartilage Layer: An In Vitro Study of Arthroscopic and Open Techniques

2019 ◽  
Vol 47 (11) ◽  
pp. 2584-2588
Author(s):  
Adam B. Yanke ◽  
Andrew S. Lee ◽  
Vasili Karas ◽  
Geoffrey Abrams ◽  
Mark L. Riccio ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Cartilage Defects ◽  
Micro Computed Tomography ◽  
In Vivo Models ◽  
Cartilage Layer ◽  
Calcified Cartilage ◽  
Restoration Technique ◽  
Significant Difference

Background: Microfracture is a commonly utilized cartilage restoration technique for articular cartilage defects. While the removal of the calcified cartilage layer (CCL) has been shown to be critical with in vivo models, little is known with regard to surgeon reliability to adequately perform the technique. Purpose: To evaluate surgeon reliability in removing the CCL utilizing open and arthroscopic techniques. Study Design: Controlled laboratory study. Methods: Eleven cadaveric knees were utilized to create four 12-mm diameter defects in the anterior and posterior medial femoral condyles. Eleven fellowship-trained surgeons were asked to perform the following procedures: remove the CCL open, retain the CCL open, remove the CCL arthroscopically, and retain the CCL arthroscopically. Samples underwent histologic staining and analysis with 3-dimensional micro–computed tomography. The latter was used to calculate the percentage of the CCL that was removed or retained across the entire defect. Results: When surgeons were asked to retain the CCL arthroscopically, 48% ± 41% (mean ± SD) remained. When surgeons were asked to remove the CCL arthroscopically, 24% ± 35% remained. There was no statistical difference between these groups ( P > .05). When the CCL was retained during open preparation, 60% ± 39% remained. During attempts to remove the CCL in an open manner, 19% ± 28% remained. There was a significant difference in the amount of CCL remaining between the open removal and open retaining groups ( P = .03). There were no significant differences in the percentage of CCL remaining between the open and arthroscopic preservation groups and between the open and arthroscopic removal groups. Conclusion/Clinical Relevance: This study highlights the significant variability in surgeon ability to reliably retain or remove the CCL. However, there appears to be improved ability of surgeons to more reliably remove or retain the CCL in an open fashion as compared with the arthroscopic approach.

scholarly journals Comparison of Obturation Quality after MTA Orthograde Filling with Various Obturation Techniques

2021 ◽  
Vol 10 (8) ◽  
pp. 1719
Author(s):  
Hae Jin An ◽  
Hyunjung Yoon ◽  
Hoi In Jung ◽  
Dong-Hoon Shin ◽  
Minju Song
Keyword(s):  
Computed Tomography ◽  
Mineral Trioxide Aggregate ◽  
Total Porosity ◽  
Filling Material ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Maxillary Molars ◽  
Percentage Volume ◽  
Ct Analysis ◽  
Total P

This study aimed to quantify and compare the obturation quality after mineral trioxide aggregate (MTA) orthograde fillings with three different obturation techniques. Thirty-three extracted human maxillary molars were collected. Distobuccal and palatal canals were prepared to an apical size of #40/06 with a Profile Ni-Ti system. All 66 canals were divided into two groups according to the material (EZ-seal or OrthoMTA) and then obturated using three different techniques: manual compaction using S-kondenser (group H), compactor activation (group C), or reverse rotary motion of Ni-Ti file (group R). The obturated roots were scanned using micro-computed tomography (micro-CT). The percentage of voids located in the apical 5 mm was measured separately, that is, closed, open, and total porosity. There was no relation between the filling material and obturation technique (p > 0.05). The percentage volume of open and total porosity was higher in EZ-seal than in OrthoMTA (open: p = 0.002, total: p = 0.001). Group H showed higher open and total porosity than groups C and R. Micro-CT analysis showed that the void volume after orthograde MTA fillings significantly decreased when the additional activation was accompanied by hand condensation. Obturation with a Ni-Ti file using reverse motion could be recommended as an MTA orthograde filling technique.

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