Analysis of bone demineralization due to the use of exoprosthesis by comparing Young’s Modulus of the femur in unilateral transfemoral amputees

2011 ◽  
Vol 35 (4) ◽  
pp. 459-466 ◽  
Author(s):  
Juan Fernando Ramírez ◽  
Jésica Andrea Isaza ◽  
Isabela Mariaka ◽  
Jaime Andrés Vélez
Keyword(s):  
Bone Density ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Ct Images ◽  
P Value ◽  
Hounsfield Units ◽  
Bone Demineralization ◽  
Bone Properties ◽  
Significant Difference ◽  
Transfemoral Amputees

Background: There is a relation between Hounsfield units obtained from computed tomography (CT) scans and bone density. The density of the bones can be used to establish its mechanical properties and therefore to assess the bone mechanical condition using CT images. Objectives: To identify the effect of the transfemoral amputation and the use of external lower limb prosthesis in the bone properties, by comparing Young’s modulus. Study Design: Young’s modulus comparison. Methods: Comparison of bone density between the healthy femur and the amputated bone of 20 unilateral transfemoral amputees was done by generating three histograms of the Hounsfield units at different parts of the femur. The histograms were created based on images obtained by CT and the Hounsfield units were translated to Young’s modulus to establish the comparison. Results: The results show a significant difference ( p-value <0.05) between the mean value of Young’s modulus of healthy and amputated bone. Conclusions: There is clearly a direct association between the use of external prosthesis and the bone demineralization due the stress shielding phenomenon. The Young’s modulus comparison using information from CT images can be a suitable tool to analyze the bone demineralization due to the use of exoprosthesis.

scholarly journals Latihan Fisik Intesitas Submaksimal dan Kalsitonin Salmon Meningkatkan Kepadatan Tulang Tikus Masa Pertumbuhan

2018 ◽  
Author(s):  
Heru Syarli Lesmana ◽  
Gadis Meinar Sari ◽  
Choesnan Effendi ◽  
Shinta Arisant
Keyword(s):  
Bone Density ◽  
Salmon Calcitonin ◽  
Bone Matrix ◽  
Growth Period ◽  
Control Group ◽  
P Value ◽  
Type I ◽  
Femur Bone ◽  
Risk Increase ◽  
Significant Difference

Bone is a complex tissue consisting of cells and matrix. Mass and thick bone mass has a dynamic addition and subtraction through the process of remodeling (bone matrix absorbed and formed again). Bone is formatted by osteoblast cell and resorption by osteoclast cell. Osteoblasts produce a matrix of osteoid, which is composed mainly of type I collagen, and osteoclast removes bone tissue by removing its mineralized matrix and breaking up the organic bone. Bone remodeling purpose to defend shape and structure of bone. the purpose of this study is to prove that submaximal-intensity exercise and salmon calcitonin improve bone density in growing rat this research method uses design of the randomize posttest only control group design. We compered femur bone density in 24 male norvegicus rats aged 6 weeks that were divided into 4 groups: controls, calcitonin, exercise, combine. Exercise group swam 3 times a week in submaximal intensity, calcitonin group injected synthetic salmon calcitonin 2 iu /100 gram of rat weight every day and combine group did both of it. After 8 weeks, rat femur bone density measured using ultrasound. the result: there are significant differences in bone density between group 1 (control) and group 4 (combine) with p = 0.001, thus the p value &lt;0.05 indicates that there is a significant difference to the average density in both groups. While comparisons to other groups found no significant difference because the value of p&gt; 0.05. the benefits of this research are calcitonin salmon and submaximal-intensity exercise increase the density bone in the growth period. High bone density is mean the bone is strong and health, not porous and fragile so decrease bone fracture risk. increase the bone density in of growth period make the bone get the best mass, and avoid from early osteoporosis.

scholarly journals Gender differences in the maxillary sinus volume : a study using computed tomography scans of a sample of Tamil Nadu population

2016 ◽  
Vol 05 (03) ◽  
pp. 138-142
Author(s):  
N Muthukumaravel ◽  
K. Y. Manjunath
Keyword(s):  
Computed Tomography ◽  
Maxillary Sinus ◽  
Tamil Nadu ◽  
Ct Images ◽  
Ct Scans ◽  
P Value ◽  
Gender Determination ◽  
Maxillary Sinus Volume ◽  
Significant Difference ◽  
Maxillary Sinuses

Abstract Background and aims : Measurements of the maxillary sinus volumes in computed tomography (CT) scans can be used for determination of gender when other methods are inconclusive. Maxillary sinus dimension measurements are valuable in studying sexual dimorphism and can assist in gender determination. The radiographic images can provide adequate measurements for maxillary sinuses that cannot be approached by other means. The purpose of the present study was to determine and compare the volume of the maxillary sinus between males and females of Tamil Nadu region using CT scans. Materials and methods : This study was carried out by using CT images of head region of 100 males and 100 females who underwent CT scanning for indications other than the pathology of the maxillary sinuses. The CT images obtained were of patients between 20 to 50 years of age. The maxillary sinus volume of each side were calculated by using the following formula: Maximal width X Maximal height X Maximal depth X 0.5. Comparison of data between genders and sides was done. The statistical inference was derived by applying unpaired student "t" test and the p value was obtained (p value <.05 was considered statistical significant). Results: Oncomparison of males with females, the mean volumes of maxillary sinuses on each side (left and right) had shown a statistically significant difference (p<.OOOl ). The maxillary sinus volumes of the males were found to be significantly higher than that of the females. Among males, the average mean volume of maxillary sinuses (right + left) is 15.15 ± 0.45 cm3. Among females, the average mean volume of maxillary sinuses (right + left) is 12.77 ± 1.34 em' which is significantly lesser than that of the males. Conclusion : It can be concluded that the volumes of the maxillary sinuses of males are larger than those of the females and this difference is statistically significant. Maxillary sinus dimension measurements can assist in gender determination.

scholarly journals Modulating physical properties of porcine urethra with injection of novel biomimetic proteoglycans ex vivo

2019 ◽  
Vol 9 (4) ◽  
pp. 20190013 ◽  
Author(s):  
Alicia S. Kriete ◽  
Katsiaryna Prudnikova ◽  
Michele S. Marcolongo
Keyword(s):  
Urinary Incontinence ◽  
Physical Properties ◽  
Young’S Modulus ◽  
Water Uptake ◽  
Ex Vivo ◽  
Young's Modulus ◽  
Radial Expansion ◽  
Significant Difference ◽  
Testing Data ◽  
Phosphate Buffered Saline

Urinary incontinence is a significant challenge for women who are affected by it. We propose augmenting the tissue structure to restore normal biomechanics by molecularly engineering the tissue using a novel family of biomimetic proteoglycans (BPGs). This work examines the ability of BPGs to modulate the mechanical and physical properties of porcine urethras ex vivo to determine the feasibility of BPGs to be implemented as molecular treatment for stress urinary incontinence (SUI). We investigated compliance by performing a unique radial expansion testing method using urethras from six- to nine-month-old pigs. The urethras were injected with 0.5 ml BPG solution at three sites every approximately 120° (conc.: 25 mg ml −1 , 50 mg ml −1 and 75 mg ml −1 in 1× phosphate-buffered saline (PBS); n = 4 per group) and compared them with PBS-injected controls. Young's modulus was calculated by treating the urethra as a thin-walled pressure vessel. A water uptake study was performed by soaking 10 mm urethra biopsy samples that were injected with 0.1 ml BPG solution (conc.: 50 mg ml −1 , 100 mg ml −1 and 200 mg ml −1 in 1× PBS; n = 6 per group) in 5 ml PBS for 24 h. Although there was no significant difference in Young's modulus data, there were differences between groups as can be seen in the raw radial expansion testing data. Results showed that BPGs have the potential to increase hydration in samples, and that there was a significant difference in water uptake between BPG-injected samples and the controls (100 mg ml −1 samples versus PBS samples, p < 0.05). This work shows that BPGs have the potential to be implemented as a molecular treatment for SUI, by restoring the diminished proteoglycan content and subsequently increasing hydration and improving the compliance of urethral tissue.

Combination of ultrasonic elastography and Ki-67 index as a novel predictive modality for the prognosis in clinic stage III breast cancer

2019 ◽  
Author(s):  
Rui Du ◽  
Weiwei Shu ◽  
Baoding Chen ◽  
Xin Zhang ◽  
Xincai Wu ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Cox Model ◽  
Strain Ratio ◽  
Survival Prediction ◽  
Concordance Index ◽  
Ki 67 ◽  
Significant Difference

Abstract Background To investigate the feasibility of combination of ultrasonic elastography (UE) and Ki-67 index as a novel predictive modality for the prognosis of clinic stage Ⅲ breast cancer. Methods Of 112 patients, Multi-parameter of UE were obtained after analyzing elastograms of 112 lesions which were recorded classification of Ki-67 by histopathologic diagnosis. Multivariate Survival analysis was performed by using multivariate Cox model. The nomograms was established to predict the probability of clinic stage Ⅲ breast cancer according to the selected independently significant variables in the multivariate Cox model. The model was internally validated using Harrell’s concordance index. Results ⅢC had significant difference in all ultrasonic elastography (UE) parameters (P < 0.05) and were statistically different from ⅢA and ⅢB (P < 0.01). The Cox model was RR (t)= Exp(1.104* X1+0.901*X4+0.972*X5) (X1: classification of Ki-67, X4: classification of strain ratio, X5: classification of Young's modulus). The nomogram showed that Ki-67 had the greatest influence on survival prediction, followed by Young's modulus and strain ratio. Internal validation revealed a concordance index of 0.76. Conclusions Our study explored a novel modality in predicting the prognosis of clinic stage Ⅲ breast cancer combining a tumor marker with breast UE imaging. A nomogram was developed to prove that the model was helpful to estimate the 5-year survival of the patients.

Comparison of Microstructure and Mechanical Properties of Aluminum Components Manufactured by CMT

2017 ◽  
Vol 898 ◽  
pp. 1318-1324 ◽  
Author(s):  
Y. Zhao ◽  
Jian Xiao ◽  
S.J. Chen
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Ultrasonic Method ◽  
Fusion Line ◽  
Al Alloy ◽  
Continuous Growth ◽  
Line Region ◽  
Significant Difference

This paper presents an investigation on the microstructure and mechanical property of Al-alloy parts made by using additive manufacturing based on CMT (Cold Metal Transfer) welding technology. With the same 3D model and process parameters, a set of hollow cylindrical parts with 100 layers were built up using 2319, 4043, 5356 aluminum welding wires, respectively. Then their microstructure, tensile strength, and microhardness were tested and analyzed comparatively. The layer bands characteristics were obviously observed in both 2319 and 4043 parts. In the interlayer region of the 2319 parts, the segregation of alloying elements on the grain boundaries and inside the grains were significantly more than that in the fusion line region. For the microstructure of 4043 parts, the dendrites grow upward from the bottom without interruption in the fusion line region, and the continuous growth structure was maintained. There is no obviously change on the microhardness from the bottom to the top because the organization is uniform and there is no significant difference in the grain size. The ultimate strength and elongation in the horizontal direction were higher than those in the longitudinal direction, and the 5356 parts had best mechanical properties among the three materials. Ultrasonic method was also used to measure the Young's modulus of the additive manufactured parts. The Young's modulus measuring results were accordant with the results obtained by the mechanical property testing, and the error was within 3%.

MECHANICAL PROPERTIES OF CHORDAE TENDINEAE OF THE MITRAL HEART VALVE: YOUNG'S MODULUS, STRUCTURAL STIFFNESS, AND EFFECTS OF AGING

2011 ◽  
Vol 11 (01) ◽  
pp. 221-230 ◽  
Author(s):  
LAURA MILLARD ◽  
DANIEL M. ESPINO ◽  
DUNCAN E. T. SHEPHERD ◽  
DAVID W. L. HUKINS ◽  
KEITH G. BUCHAN
Keyword(s):  
Mechanical Properties ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Finite Element Models ◽  
Structural Stiffness ◽  
Posterior Leaflet ◽  
Chordae Tendineae ◽  
Significant Difference ◽  
Valve Function ◽  
Effects Of Aging

Young's modulus and structural stiffness were determined for chordae tendineae of the mitral valve from young (18–26 weeks) and old (over 2 years) porcine hearts. For chordae from the posterior leaflet of the valve, the Young's modulus values were significantly higher (p < 0.05) for the thinner marginal chordae (59 ± 31 MPa young; 88 ± 21 MPa old) than for the thicker basal chordae (31 ± 4 MPa young; 28 ± 9 MPa old). Marginal chordae (both anterior and posterior) had significantly higher (p < 0.05) value for their Young's modulus in old (88 ± 21 MPa anterior and posterior) than in young (62 ± 17 MPa anterior, 59 ± 18 MPa posterior) pig hearts. There was no significant difference in structural stiffness between marginal and basal (anterior and posterior leaflets) or between strut chordae (that are associated with anterior the leaflet only) and marginal and basal chordae. However, the value of structural stiffness of chordae was significantly higher (p < 0.05) for old (2.2 ± 0.2 kN/m) than for young (2.0 ± 0.4 kN/m) chordae. These results show that aging affects the properties of chordae and that all chordae need to be included in finite element models of valve function.

scholarly journals Ultrasonic Measurement of Bone Density and Young's Modulus

2007 ◽  
Vol 1 (12) ◽  
pp. 1412-1422
Author(s):  
Sotomi ISHIHARA ◽  
Bailin DING ◽  
Hiroshi SHIBATA ◽  
Miki OTA ◽  
Takahito GOSHIMA ◽  
...  
Keyword(s):  
Bone Density ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Ultrasonic Measurement

scholarly journals Evaluation of The Bio-Stimulatory Effect of Platelet Rich Fibrin Augmented by Diode LASER Compared to Platelet Rich Fibrin Alone on Dental Implant Replacing Posterior Mandibular Teeth. Randomised Clinical Trial: Split Mouth Study

2019 ◽  
Vol 7 (5) ◽  
pp. 869-875
Author(s):  
Sherif Shafik Mohamed El Bahnasy ◽  
Mohamed Khalifa Zayet ◽  
Tarek Ibrahim El-Ghareeb ◽  
Hoda Abd Kader Saleh
Keyword(s):  
Bone Density ◽  
Dental Implant ◽  
Randomised Clinical Trial ◽  
Control Group ◽  
P Value ◽  
Platelet Rich Fibrin ◽  
Post Operative Pain ◽  
Significant Difference ◽  
And Control

BACKGROUND: Restoring masticatory function and replacing missing teeth with minimal pain and discomfort are the most important issues for the patient and clinician. Nowadays dental implants became the most popular line of treatment to replace missing teeth; offering a comfortable long lasting prosthesis. Osseo-integration reflects the long term success of a dental implant. Many bio-modulators are used aiming to improve the osseointegration and healing around dental implants such as Low-Level Laser treatment (LLLT) and Platelet Rich Fibrin (PRF). PRF has been proven to improve bone repair process around the dental implant. LLLT is considered a noninvasive, safe technique that stimulates osteogenesis and alleviates post-operative pain. AIM: Evaluation of the bio-stimulatory effect of LLLT on a dental implant with PRF compared to PRF alone clinically and radiographically. METHODS: A randomised clinical trial with the split-mouth design was conducted on nine patients with bilaterally missing lower posterior tooth. All patients received one dental implant on each side with PRF. LASER application was performed to one side twice weekly for one month starting on the day of insertion. Post-operative pain was assessed daily through the first week using numerical rating pain scale (NRS) as the primary outcome. Relative peri-implant bone density was measured using direct digital intraoral radiography immediately after insertion, one, four and nine months postoperatively. Implants stability were measured using radio frequency assessment immediately after insertion, four and nine months post-operative as secondary outcomes. RESULTS: The NRS for pain was significantly decreased by the end of the first-week postoperatively in the intervention and control group with a mean of (2.22 ± 1.56) (2.11 ± 1.83) respectively. However, there was no statistically significant difference between the test groups at P-Value (0.892). The relative bone density values were decreased by the end of the ninth month of follow-up in the intervention and control group with a mean of (134.42 ± 16.13) (128.77 ± 33.54) respectively. No statistically significant difference was observed between the two test groups at P-value (0.863). The radiofrequency values for implant stability showed no statically significant difference after nine months of follow up when compared to the initial stability values at the day of insertion in the intervention and control group. The mean radiofrequency values were (67.24 ± 1.79) and (66.9 ± 2.57) respectively, and no statistically significant difference was observed between the two test groups at P-value (0.793) CONCLUSION: There are no statistically significant differences in post-operative pain values, implant stability and bone density between the implant sites treated with PRF augmented by Diode laser compared to implant sites treated by PRF alone.

scholarly journals Spatio-temporal development of the endothelial glycocalyx layer and its mechanical property in vitro

2012 ◽  
Vol 9 (74) ◽  
pp. 2290-2298 ◽  
Author(s):  
Ke Bai ◽  
Wen Wang
Keyword(s):  
Endothelial Cells ◽  
Cell Membrane ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Umbilical Vein ◽  
Endothelial Glycocalyx ◽  
Temporal Development ◽  
Afm Indentation ◽  
Significant Difference

The endothelial glycocalyx is a thin layer of polysaccharide matrix on the luminal surface of endothelial cells (ECs), which contains sulphated proteoglycans and glycoproteins. It is a mechanotransducer and functions as an amplifier of the shear stress on ECs. It controls the vessel permeability and mediates the blood–endothelium interaction. This study investigates the spatial distribution and temporal development of the glycocalyx on cultured ECs, and evaluates mechanical properties of the glycocalyx using atomic force microscopy (AFM) nano-indentation. The glycocalyx on human umbilical vein endothelial cells (HUVECs) is observed under a confocal microscope. Manipulation of the glycocalyx is achieved using heparanase or neuraminidase. The Young's modulus of the cell membrane is calculated from the force–distance curve during AFM indentation. Results show that the glycocalyx appears predominantly on the edge of cells in the early days in culture, e.g. up to day 5 after seeding. On day 7, the glycocalyx is also seen in the apical area of the cell membrane. The thickness of the glycocalyx is approximately 300 nm–1 μm. AFM indentation reveals the Young's modulus of the cell membrane decreases from day 3 (2.93 ± 1.16 kPa) to day 14 (0.35 ± 0.15 kPa) and remains unchanged to day 21 (0.33 ± 0.19 kPa). Significant difference in the Young's modulus is also seen between the apical (1.54 ± 0.58 kPa) and the edge (0.69 ± 0.55 kPa) of cells at day 7. By contrast, neuraminidase-treated cells (i.e. without the glycocalyx) have similar values between day 3 (3.18 ± 0.88 kPa), day 14 (2.12 ± 0.78 kPa) and day 21 (2.15 ± 0.48 kPa). The endothelial glycocalyx in vitro shows temporal development in the early days in culture. It covers predominantly the edge of cells initially and appears on the apical membrane of cells as time progresses. The Young's modulus of the glycocalyx is deduced from Young's moduli of cell membranes with and without the glycocalyx layer. Our results show the glycocalyx on cultured HUVECs has a Young's modulus of approximately 0.39 kPa.

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