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Hugo Giambini - One of the best experts on this subject based on the ideXlab platform.
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Extensibility of the supraspinatus muscle can be predicted by combining shear wave elastography and magnetic resonance imaging measured quantitative metrics of stiffness and volumetric fat infiltration a cadaveric study
Clinical Biomechanics, 2018Co-Authors: Hugo Giambini, Asghar RezaeiAbstract:Abstract Background A torn rotator cuff tendon will retract over time causing changes in muscle properties and decreasing its Extensibility, or deformation. During surgery, large tensile loads are applied to bring the torn tendon to the footprint. Poor muscle Extensibility and large tensile stresses at the repair might lead to gap formation or re-tear of the repair. A quantitative evaluation of muscle properties could be used to predict the Extensibility of the supraspinatus (SSP) muscle. Method Magnetic resonance imaging (MRI)-measured volumetric fat fraction and shear wave elastography (SWE)-measured elastic modulus of the SSP muscle were obtained on seventeen cadaveric shoulders. Experimental Extensibility and stiffness were then measured by axially pulling the tendon up-to 60 N. Univariate and multivariate analyses were used to determine the correlation and contribution of fat fraction and elastic modulus to experimental outcomes. Findings SWE moduli negatively correlated with SSP muscle Extensibility (r = 0.54–0.58, P ≤ 0.0259); fat fraction resulted in a positive correlation (r = 0.69, P = 0.0021). SWE measurements, solely, explained up to 34% and 33% of the variability in measured Extensibility and stiffness, respectively. Fat Fraction, solely, explained 48% of the variability in Extensibility and 36% of the variability in stiffness. These methods combined predicted up to 62% of the musculotendinous Extensibility. Interpretation This study showed a comprehensive quantitative assessment of SSP muscle properties using SWE to estimate stiffness and MRI to measure fatty infiltration. The Extensibility of the detached muscle/tendon unit was highly correlated to material properties of the muscle when these methods were used in combination.
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quantifying Extensibility of rotator cuff muscle with tendon rupture using shear wave elastography a cadaveric study
Journal of Biomechanics, 2017Co-Authors: Taku Hatta, Yoshiaki Itoigawa, John W. Sperling, Scott P. Steinmann, Hugo Giambini, Alexander W Hooke, Eiji ItoiAbstract:Surgical repair for large rotator cuff tear remains challenging due to tear size, altered muscle mechanical properties, and poor musculotendinous Extensibility. Insufficient Extensibility might lead to an incomplete reconstruction; moreover, excessive stresses after repair may result in repair failure without healing. Therefore, estimates of Extensibility of cuff muscles can help in pre-surgical planning to prevent unexpected scenarios during surgery. The purpose of this study was to determine if quantified mechanical properties of the supraspinatus muscle using shear wave elastography (SWE) could be used to predict the Extensibility of the musculotendinous unit on cadaveric specimens. Forty-five fresh-frozen cadaveric shoulders (25 intact and 20 with rotator cuff tear) were used for the study. Passive stiffness of 4 anatomical regions in the supraspinatus muscle was first measured using SWE. After detaching the distal edge of supraspinatus muscle from other cuff muscles, the detached muscle was axially pulled with the scapula fixed. The correlation between the SWE modulus and the Extensibility of the muscle under 30 and 60N loads was assessed. There was a significant negative correlation between SWE measurements and the experimental Extensibility. SWE modulus for the anterior-deep region in the supraspinatus muscle showed the strongest correlation with Extensibility under 30N (r=0.70, P<0.001) and 60N (r=0.68, P<0.001). Quantitative SWE assessment for the supraspinatus muscle was highly correlated with Extensibility of musculotendinous unit on cadaveric shoulders. This technique may be used to predict the Extensibility for rotator cuff tears for pre-surgical planning.
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Intramuscular fat infiltration evaluated by magnetic resonance imaging predicts the Extensibility of the supraspinatus muscle
Muscle & nerve, 2017Co-Authors: Hugo Giambini, Krzysztof R. Gorny, Per Widholm, Anette Karlsson, Olof Dahlqvist Leinhard, Mark C. Adkins, Chunfeng ZhaoAbstract:Introduction: Rotator cuff (RC) tears result in muscle atrophy and fat infiltration within the RC muscles. An estimation of muscle quality and deformation, or Extensibility, is useful in selecting the most appropriate surgical procedure. We determined if non-invasive quantitative assessment of intramuscular fat using MRI could be used to predict Extensibility of the supraspinatus (SSP) muscle. Methods: Seventeen cadaveric shoulders were imaged to assess intramuscular fat infiltration. Extensibility and histological evaluations were then performed. Results: Quantitative fat infiltration positively correlated with histological findings and presented a positive correlation with muscle Extensibility (r = 0.69; p = 0.002). Extensibility was not significantly different between shoulders graded with a higher fat content vs. those with low fat when implementing qualitative methods. Discussion: A non-invasive prediction of whole-muscle Extensibility may directly guide pre-operative planning to determine if the torn edge could efficiently cover the original footprint while aiding in postoperative evaluation of RC repair. This article is protected by copyright. All rights reserved.
Takayuki Hoson - One of the best experts on this subject based on the ideXlab platform.
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Role of xyloglucan in gravitropic bending of azuki bean epicotyl.
Physiologia Plantarum, 2008Co-Authors: Toshimitsu Ikushima, Kouichi Soga, Takayuki Hoson, Teruo ShimmenAbstract:The mechanism of the gravitropic bending was studied in azuki bean epicotyls. The cell wall Extensibility of the lower side became higher than that of the upper side in the epicotyl bending upward. The contents of matrix polysaccharides of the cell wall (pectin and xyloglucan in hemicellulose-II) in the lower side became smaller than those in the upper side. The molecular mass of xyloglucans in the lower side decreased. After an epicotyl was fixed to a metal rod to prevent the bending, gravistimulation was applied. Fundamentally the same results were obtained with respect to rheological and chemical characteristics of the cell wall as those of epicotyls showing gravitropic bending. The present results suggested that the initial gravitropic bending was caused by the increase in Extensibility of the lower side and the decrease in Extensibility of the upper side via the change of the cell wall matrix, especially xyloglucans.
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xyloglucan oligosaccharides cause cell wall loosening by enhancing xyloglucan endotransglucosylase hydrolase activity in azuki bean epicotyls
Plant and Cell Physiology, 2004Co-Authors: Tomomi Kaku, Kazuyuki Wakabayashi, Akira Tabuchi, Takayuki HosonAbstract:;Addition of xyloglucan-derived oligosaccharides shifted the wall-bound xyloglucans to a lower molecular mass distribution and increased the cell wall Extensibility of the native epidermal tissue strips isolated from azuki bean (Vigna angularis) epicotyls. To ascertain the mechanism of oligosaccharide function, we examined the action of a xyloglucan endotransglucosylase/hydrolase (XTH) showing both endotransglucosylase and endohydrolase activities, isolated from azuki bean epicotyl cell walls, in the presence of xyloglucan oligosaccharides. The addition of xyloglucan oligosaccharides enhanced the xyloglucan-degrading activity of XTH against isolated xyloglucan substrates. When the methanol-fixed epidermal tissue strips were incubated with XTH, the molecular mass of wall-bound xyloglucans was decreased and the cell wall Extensibility increased markedly in the presence of the oligosaccharides. These results suggest that xyloglucan oligosaccharides stimulate the degradation of xyloglucans by enhancing the XTH activity within the cell wall architecture, thereby increasing the cell wall Extensibility in azuki bean epicotyls.
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temperature modulates the cell wall mechanical properties of rice coleoptiles by altering the molecular mass of hemicellulosic polysaccharides
Physiologia Plantarum, 2003Co-Authors: Yukiko Nakamura, Kazuyuki Wakabayashi, Takayuki HosonAbstract:The present study was conducted to investigate the mechanism inducing the difference in the cell wall Extensibility of rice (Oryza sativa L. cv. Koshihikari) coleoptiles grown under various temperature (10-50 degrees C) conditions. The growth rate and the cell wall Extensibility of rice coleoptiles exhibited the maximum value at 30-40 degrees C, and became smaller as the growth temperature rose or dropped from this temperature range. The amounts of cell wall polysaccharides per unit length of coleoptile increased in coleoptiles grown at 40 degrees C, but not at other temperature conditions. On the other hand, the molecular size of hemicellulosic polysaccharides was small at temperatures where the cell wall Extensibility was high (30-40 degrees C). The autolytic activities of cell walls obtained from coleoptiles grown at 30 and 40 degrees C were substantially higher than those grown at 10, 20 and 50 degrees C. Furthermore, the activities of (1-->3),(1-->4)-beta-glucanases extracted from coleoptile cell walls showed a similar tendency. When oat (1-->3),(1-->4)-beta-glucans with high molecular mass were incubated with the cell wall enzyme preparations from coleoptiles grown at various temperature conditions, the extensive molecular mass downshifts were brought about only by the cell wall enzymes obtained from coleoptiles grown at 30-40 degrees C. There were close correlations between the cell wall Extensibility and the molecular mass of hemicellulosic polysaccharides or the activity of beta -glucanases. These results suggest that the environmental temperature regulates the cell wall Extensibility of rice coleoptiles by modifying mainly the molecular mass of hemicellulosic polysaccharides. Modulation of the activity of beta-glucanases under various temperature conditions may be involved in the alteration of the molecular size of hemicellulosic polysaccharides.
Hishashi Okamoto - One of the best experts on this subject based on the ideXlab platform.
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responses of elongation growth rate turgor pressure and cell wall Extensibility of stem cells of impatiens balsamina to lead cadmium and zinc
Biometals, 1993Co-Authors: Sharifah Barlian Aidid, Hishashi OkamotoAbstract:Elongation growth rate of stem cells of Impatiens balsamina was inhibited by the heavy metals Pb2+, Cd2+ and Zn2+ due to their suppression on cell wall Extensibility. Effective turgor was also inhibited by Pb2+ and Cd2+ but it played a secondary role in reducing the stem cell elongation growth rate. The major rate-limiting factor for cell elongation growth was the cell wall Extensibility. Furthermore, Cd2+ was found to be more toxic than Pb2+, while Pb2+ was more toxic than Zn2+.
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responses of elongation growth rate turgor pressure and cell wall Extensibility of stem cells of impatiens balsamina to lead cadmium and zinc
Biometals, 1993Co-Authors: Sharifah Barlian Aidid, Hishashi OkamotoAbstract:Elongation growth rate of stem cells of Impatiens balsamina was inhibited by the heavy metals Pb2+, Cd2+ and Zn2+ due to their suppression on cell wall Extensibility. Effective turgor was also inhibited by Pb2+ and Cd2+ but it played a secondary role in reducing the stem cell elongation growth rate. The major rate-limiting factor for cell elongation growth was the cell wall Extensibility. Furthermore, Cd2+ was found to be more toxic than Pb2+, while Pb2+ was more toxic than Zn2+.
Asghar Rezaei - One of the best experts on this subject based on the ideXlab platform.
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Extensibility of the supraspinatus muscle can be predicted by combining shear wave elastography and magnetic resonance imaging measured quantitative metrics of stiffness and volumetric fat infiltration a cadaveric study
Clinical Biomechanics, 2018Co-Authors: Hugo Giambini, Asghar RezaeiAbstract:Abstract Background A torn rotator cuff tendon will retract over time causing changes in muscle properties and decreasing its Extensibility, or deformation. During surgery, large tensile loads are applied to bring the torn tendon to the footprint. Poor muscle Extensibility and large tensile stresses at the repair might lead to gap formation or re-tear of the repair. A quantitative evaluation of muscle properties could be used to predict the Extensibility of the supraspinatus (SSP) muscle. Method Magnetic resonance imaging (MRI)-measured volumetric fat fraction and shear wave elastography (SWE)-measured elastic modulus of the SSP muscle were obtained on seventeen cadaveric shoulders. Experimental Extensibility and stiffness were then measured by axially pulling the tendon up-to 60 N. Univariate and multivariate analyses were used to determine the correlation and contribution of fat fraction and elastic modulus to experimental outcomes. Findings SWE moduli negatively correlated with SSP muscle Extensibility (r = 0.54–0.58, P ≤ 0.0259); fat fraction resulted in a positive correlation (r = 0.69, P = 0.0021). SWE measurements, solely, explained up to 34% and 33% of the variability in measured Extensibility and stiffness, respectively. Fat Fraction, solely, explained 48% of the variability in Extensibility and 36% of the variability in stiffness. These methods combined predicted up to 62% of the musculotendinous Extensibility. Interpretation This study showed a comprehensive quantitative assessment of SSP muscle properties using SWE to estimate stiffness and MRI to measure fatty infiltration. The Extensibility of the detached muscle/tendon unit was highly correlated to material properties of the muscle when these methods were used in combination.
W H Eisma - One of the best experts on this subject based on the ideXlab platform.
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Extensibility and stiffness of the hamstrings in patients with nonspecific low back pain
Archives of Physical Medicine and Rehabilitation, 2001Co-Authors: J P K Halbertsma, L N H Goeken, At L Hof, Johan W Groothoff, W H EismaAbstract:Abstract Halbertsma JPK, Goeken LNH, Hof AL, Groothoff JW, Eisma WH. Extensibility and stiffness of the hamstrings in patients with nonspecific low back pain. Arch Phys Med Rehabil 2001;82:232-8. Objective: To investigate the Extensibility and stiffness of the hamstrings in patients with nonspecific low back pain (LBP). Design: An experimental design. Setting: A university laboratory for human movement analysis in a department of rehabilitation medicine. Participants: Forty subjects, a patient group (20) and a healthy control group (20). Interventions: Subjects laid supine on an examination table with a lift frame, with left leg placed in a sling at the ankle. Straight leg raising, pulling force, and activity of hamstring and back muscles were recorded with electrodes. Patients indicated when they experienced tension or pain. Main Outcome Measures: The lift force, leg excursion, pelvic-femoral angle, first sensation of pain, and the electromyogram of the hamstrings and back muscles measured in an experimental straight-leg raising set-up. Results: The patient group showed a significant restriction in range of motion (ROM) and Extensibility of the hamstrings compared with the control group. No significant difference in hamstring muscle stiffness can be assessed between both groups. Conclusion: The restricted ROM and the decreased Extensibility of the hamstrings in patients with nonspecific LBP is not caused by increased muscle stiffness of the hamstrings, but determined by the stretch tolerance of the patients.
