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Sample records for cartilage formation measured

  1. Facilitating cartilage volume measurement using MRI

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    Maataoui, Adel, E-mail: adel.maataoui@gmx.d [Institute for Diagnostic and Interventional Radiology, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main (Germany); Gurung, Jessen, E-mail: jessen.gurung@gmx.d [Institute for Diagnostic and Interventional Radiology, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main (Germany); Ackermann, Hanns, E-mail: h.ackermann@add.uni-frankfurt.d [Institute for Epidemiology and Medical Statistics, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main (Germany); Abolmaali, Nasreddin [Biological and Molecular Imaging, ZIK OncoRay - Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307 Dresden (Germany); Kafchitsas, Konstantinos [Department of Orthopedics and Orthopedic Surgery, Johannes Gutenberg University, Langenbeckstrasse 1, 55131 Mainz (Germany); Vogl, Thomas J., E-mail: t.vogl@em.uni-frankfurt.d [Institute for Diagnostic and Interventional Radiology, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main (Germany); Khan, M. Fawad, E-mail: fawad@gmx.d [Institute for Diagnostic and Interventional Radiology, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main (Germany)

    2010-08-15

    Purpose: To compare quantitative cartilage volume measurement (CVM) using different slice thicknesses. Materials and methods: Ten knees were scanned with a 1.5 T MRI (Sonata, Siemens, Erlangen, Germany) using a 3D gradient echo sequence (FLASH, fast low-angle shot). Cartilage volume of the medial and lateral tibial plateau was measured by two independent readers in 1.5 mm, 3.0 mm and 5.0 mm slices using the Argus software application. Accuracy and time effectiveness served as control parameters. Results: Determining cartilage volume, time for calculation diminished for the lateral tibial plateau from 384.6 {+-} 127.7 s and 379.1 {+-} 117.6 s to 214.9 {+-} 109.9 s and 213.9 {+-} 102.2 s to 122.1 {+-} 60.1 s and 126.8 {+-} 56.2 s and for the medial tibial plateau from 465.0 {+-} 147.7 s and 461.8 {+-} 142.7 s to 214.0 {+-} 67.9 s and 208.9 {+-} 66.2 s to 132.6 {+-} 41.5 s and 130.6 {+-} 42.0 s measuring 1.5 mm, 3 mm and 5 mm slices, respectively. No statistically significant difference between cartilage volume measurements was observed (p > 0.05) while very good inter-reader correlation was evaluated. Conclusion: CVM using 1.5 mm slices provides no higher accuracy than cartilage volume measurement in 5 mm slices while an overall time saving up to 70% is possible.

  2. Articular cartilage thickness measured with US is not as easy as it appears

    DEFF Research Database (Denmark)

    Torp-Pedersen, S; Bartels, E M; Wilhjelm, Jens E.;

    2011-01-01

    Theoretically, the high spatial resolution of US makes it well suited to monitor the decrease in articular cartilage thickness in osteoarthritis. A requirement is, however, that the borders of the cartilage are correctly identified and that the cartilage is measured under orthogonal insonation....... If US measurements are compared to measurements with other techniques, they should be corrected for the higher sound speed in cartilage....

  3. Optical coherence tomography enables accurate measurement of equine cartilage thickness for determination of speed of sound.

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    Puhakka, Pia H; Te Moller, Nikae C R; Tanska, Petri; Saarakkala, Simo; Tiitu, Virpi; Korhonen, Rami K; Brommer, Harold; Virén, Tuomas; Jurvelin, Jukka S; Töyräs, Juha

    2016-08-01

    Background and purpose - Arthroscopic estimation of articular cartilage thickness is important for scoring of lesion severity, and measurement of cartilage speed of sound (SOS)-a sensitive index of changes in cartilage composition. We investigated the accuracy of optical coherence tomography (OCT) in measurements of cartilage thickness and determined SOS by combining OCT thickness and ultrasound (US) time-of-flight (TOF) measurements. Material and methods - Cartilage thickness measurements from OCT and microscopy images of 94 equine osteochondral samples were compared. Then, SOS in cartilage was determined using simultaneous OCT thickness and US TOF measurements. SOS was then compared with the compositional, structural, and mechanical properties of cartilage. Results - Measurements of non-calcified cartilage thickness using OCT and microscopy were significantly correlated (ρ = 0.92; p measurement of articular cartilage thickness. Although SOS measurements lacked accuracy in thin equine cartilage, the concept of SOS measurement using OCT appears promising.

  4. Autophagy modulates articular cartilage vesicle formation in primary articular chondrocytes.

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    Rosenthal, Ann K; Gohr, Claudia M; Mitton-Fitzgerald, Elizabeth; Grewal, Rupinder; Ninomiya, James; Coyne, Carolyn B; Jackson, William T

    2015-05-22

    Chondrocyte-derived extracellular organelles known as articular cartilage vesicles (ACVs) participate in non-classical protein secretion, intercellular communication, and pathologic calcification. Factors affecting ACV formation and release remain poorly characterized; although in some cell types, the generation of extracellular vesicles is associated with up-regulation of autophagy. We sought to determine the role of autophagy in ACV production by primary articular chondrocytes. Using an innovative dynamic model with a light scatter nanoparticle counting apparatus, we determined the effects of autophagy modulators on ACV number and content in conditioned medium from normal adult porcine and human osteoarthritic chondrocytes. Healthy articular chondrocytes release ACVs into conditioned medium and show significant levels of ongoing autophagy. Rapamycin, which promotes autophagy, increased ACV numbers in a dose- and time-dependent manner associated with increased levels of autophagy markers and autophagosome formation. These effects were suppressed by pharmacologic autophagy inhibitors and short interfering RNA for ATG5. Caspase-3 inhibition and a Rho/ROCK inhibitor prevented rapamycin-induced increases in ACV number. Osteoarthritic chondrocytes, which are deficient in autophagy, did not increase ACV number in response to rapamycin. SMER28, which induces autophagy via an mTOR-independent mechanism, also increased ACV number. ACVs induced under all conditions had similar ecto-enzyme specific activities and types of RNA, and all ACVs contained LC3, an autophagosome-resident protein. These findings identify autophagy as a critical participant in ACV formation, and augment our understanding of ACVs in cartilage disease and repair.

  5. Quantitative spatially resolved measurements of mass transfer through laryngeal cartilage.

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    Macpherson, J V; O'Hare, D; Unwin, P R; Winlove, C P

    1997-11-01

    The scanning electrochemical microscope (SECM) is a scanned probe microscope that uses the response of a mobile ultramicroelectrode (UME) tip to determine the reactivity, topography, and mass transport characteristics of interfaces with high spatial resolution. SECM strategies for measuring the rates of solute diffusion and convection through samples of cartilage, using amperometric UMEs, are outlined. The methods are used to determine the diffusion coefficients of oxygen and ruthenium(III) hexamine [Ru(NH3)6(3+)] in laryngeal cartilage. The diffusion coefficient of oxygen in cartilage is found to be approximately 50% of that in aqueous electrolyte solution, assuming a partition coefficient of unity for oxygen between cartilage and aqueous solution. In contrast, diffusion of Ru(NH3)6(3+) within the cartilage sample cannot be detected on the SECM timescale, suggesting a diffusion coefficient at least two orders of magnitude lower than that in solution, given a measured partition coefficient for Ru(NH3)6(3+) between cartilage and aqueous solution, Kp = [Ru(NH3)6(3+)]cartilage/[RU(NH3)6(3+)]solution = 3.4 +/- 0.1. Rates of Ru(NH3)6(3+) osmotically driven convective transport across cartilage samples are imaged at high spatial resolution by monitoring the current response of a scanning UME, with an osmotic pressure of approximately 0.75 atm across the slice. A model is outlined that enables the current response to be related to the local flux. By determining the topography of the sample from the current response with no applied osmotic pressure, local transport rates can be correlated with topographical features of the sample surface, at much higher spatial resolution than has previously been achieved. PMID:9370471

  6. Tracheal cartilage regeneration and new bone formation by slow release of bone morphogenetic protein (BMP)-2.

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    Igai, Hitoshi; Chang, Sung Soo; Gotoh, Masashi; Yamamoto, Yasumichi; Yamamoto, Masaya; Tabata, Yasuhiko; Yokomise, Hiroyasu

    2008-01-01

    We investigated the efficiency of bone morphogenetic protein (BMP)-2 released slowly from gelatin sponge for tracheal cartilage regeneration. A 1-cm gap was made in the mid-ventral portion of each of 10 consecutive tracheal cartilages. In the control group (n = 4), the resulting gap was left untreated. In the gelatin group (n = 4), plain gelatin was implanted in the gap. In the BMP-2 group (n = 4), gelatin containing 100 microg BMP-2 was implanted. We euthanatized all dogs in each group at 1, 3, 6, and 12 months after the implantation, respectively, and then examined the implant site macro- and microscopically. In the BMP-2 group, regenerated fibrous cartilage and newly formed bone were observed at 1 and 12 months. Regenerated cartilage was observed at the ends of the host cartilage stumps, with newly formed bone in the middle portion. The gaps were filled with regenerated cartilage and newly formed bone. At 3 and 6 months, regenerated cartilage, but not newly formed bone, was evident. The regenerated cartilage was covered with perichondrium and showed continuity with the host cartilage. We succeeded in inducing cartilage regeneration and new bone formation in canine trachea by slow release of 100 microg BMP-2 from gelatin. PMID:18204324

  7. Procyanidin B3 prevents articular cartilage degeneration and heterotopic cartilage formation in a mouse surgical osteoarthritis model.

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    Hailati Aini

    Full Text Available Osteoarthritis (OA is a common disease in the elderly due to an imbalance in cartilage degradation and synthesis. Heterotopic ossification (HO occurs when ectopic masses of endochondral bone form within the soft tissues around the joints and is triggered by inflammation of the soft tissues. Procyanidin B3 (B3 is a procyanidin dimer that is widely studied due to its high abundance in the human diet and antioxidant activity. Here, we evaluated the role of B3 isolated from grape seeds in the maintenance of chondrocytes in vitro and in vivo. We observed that B3 inhibited H(2O(2-induced apoptosis in primary chondrocytes, suppressed H(2O(2- or IL-1ß-induced nitric oxide synthase (iNOS production, and prevented IL-1ß-induced suppression of chondrocyte differentiation marker gene expression in primary chondrocytes. Moreover, B3 treatment enhanced the early differentiation of ATDC5 cells. To examine whether B3 prevents cartilage destruction in vivo, OA was surgically induced in C57BL/6J mice followed by oral administration of B3 or vehicle control. Daily oral B3 administration protected articular cartilage from OA and prevented chondrocyte apoptosis in surgically-induced OA joints. Furthermore, B3 administration prevented heterotopic cartilage formation near the surgical region. iNOS protein expression was enhanced in the synovial tissues and the pseudocapsule around the surgical region in OA mice fed a control diet, but was reduced in mice that received B3. Together, these data indicated that in the OA model, B3 prevented OA progression and heterotopic cartilage formation, at least in a part through the suppression of iNOS. These results support the potential therapeutic benefits of B3 for treatment of human OA and heterotopic ossification.

  8. Stem cells catalyze cartilage formation by neonatal articular chondrocytes in 3D biomimetic hydrogels

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    Lai, Janice H.; Kajiyama, Glen; Smith, Robert Lane; Maloney, William; Yang, Fan

    2013-12-01

    Cartilage loss is a leading cause of disability among adults and effective therapy remains elusive. Neonatal chondrocytes (NChons) are an attractive allogeneic cell source for cartilage repair, but their clinical translation has been hindered by scarce donor availability. Here we examine the potential for catalyzing cartilage tissue formation using a minimal number of NChons by co-culturing them with adipose-derived stem cells (ADSCs) in 3D hydrogels. Using three different co-culture models, we demonstrated that the effects of co-culture on cartilage tissue formation are dependent on the intercellular distance and cell distribution in 3D. Unexpectedly, increasing ADSC ratio in mixed co-culture led to increased synergy between NChons and ADSCs, and resulted in the formation of large neocartilage nodules. This work raises the potential of utilizing stem cells to catalyze tissue formation by neonatal chondrocytes via paracrine signaling, and highlights the importance of controlling cell distribution in 3D matrices to achieve optimal synergy.

  9. Remobilization causes site-specific cyst formation in immobilization-induced knee cartilage degeneration in an immobilized rat model.

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    Nagai, Momoko; Ito, Akira; Tajino, Junichi; Iijima, Hirotaka; Yamaguchi, Shoki; Zhang, Xiangkai; Aoyama, Tomoki; Kuroki, Hiroshi

    2016-06-01

    An understanding of the articular cartilage degenerative process is necessary for the prevention and treatment of joint disease. The present study aimed to examine how long-term immobilization-induced cartilage degeneration is aggravated by remobilization. Sixty 8-week-old male Wistar rats were used in this study. The unilateral knee joint was immobilized using an external fixator for 8 weeks. The rats were killed at 0 and 3 days, and at 1, 2, 4 and 8 weeks after removing the fixator. After the rats were killed, the maximum knee extension angles were measured. Histological sections at the medial mid-condylar region (non-contact, transitional and contact regions of the femur and tibia) were prepared and scored. The cartilage thickness and number of chondrocytes were measured, and CD44 and Col2-3/4c expression levels were assessed immunohistochemically. The histological assessment revealed progressive aggravation of cartilage degeneration in the transitional region, with a decreased number of chondrocytes and CD44-positive chondrocytes as well as poor scoring over time, particularly in the tibia. Cyst formation was confirmed in the transitional region of the tibia at 8 weeks post-remobilization. The cartilage thickness in the transitional region was thicker than that in the contact region, particularly in the tibia. Col2-3/4c expression was observed in the non-contact and transitional regions, and the knee extension angle was recovered. In conclusion, immobilization-induced cartilage degeneration was aggravated by remobilization over time in the transitional region, followed by observations of a decreased number of chondrocytes and morphological disparity between different cartilage regions. PMID:26989984

  10. Ultrasonographic Measurement of the Femoral Cartilage Thickness in Hemiparetic Patients after Stroke

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    Tunc, Hakan; Oken, Oznur; Kara, Murat; Tiftik, Tulay; Dogu, Beril; Unlu, Zeliha; Ozcakar, Levent

    2012-01-01

    The aim of the study was to evaluate the femoral cartilage thicknesses of hemiparetic patients after stroke using musculoskeletal ultrasonography and to determine whether there is any correlation between cartilage thicknesses and the clinical characteristics of the patients. Femoral cartilage thicknesses of both knees were measured in 87 (33…

  11. Articular Cartilage Thickness Measured with US is Not as Easy as It Appears

    DEFF Research Database (Denmark)

    Torp-Pedersen, Søren; Bartels, E. M.; Wilhjelm, Jens E.;

    2011-01-01

    . Materials and Methods: A literature search limited to the last 10 years of studies applying US to measure cartilage thickness. Results: 15 studies were identified and they referred to another 8 studies describing methods of thickness measurement. 11 of the 15 studies identified the superficial cartilage......Background: Theoretically, the high spatial resolution of US makes it well suited to monitor the decrease in articular cartilage thickness in osteoarthritis. A requirement is, however, that the borders of the cartilage are correctly identified and that the cartilage ismeasured under orthogonal...... insonation. If US measurements are compared to measurements with other techniques, they should be corrected for the higher sound speed in cartilage. Purpose: To study whether investigators correctly identify the articular cartilage, whether they insonate orthogonally, and whether they correct for sound speed...

  12. Role of Insulin-Transferrin-Selenium in Auricular Chondrocyte Proliferation and Engineered Cartilage Formation in Vitro

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    Xia Liu

    2014-01-01

    Full Text Available The goal of this study is to determine the effects of Insulin-Transferrin-Selenium (ITS on proliferation of auricular chondrocytes and formation of engineered cartilage in vitro. Pig auricular monolayer chondrocytes and chondrocyte pellets were cultured in media containing 1% ITS at different concentrations of fetal bovine serum (FBS, 10%, 6%, 2%, 0%, or 10% FBS alone as a control for four weeks. Parameters including cell proliferation in monolayer, wet weight, collagen type I/II/X (Col I, II, X and glycosaminoglycan (GAG expression, GAG content of pellets and gene expression associated with cartilage formation/dedifferentiation (lost cartilage phenotype/hypertrophy within the chondrocyte pellets were assessed. The results showed that chondrocytes proliferation rates increased when FBS concentrations increased (2%, 6%, 10% FBS in ITS supplemented groups. In addition, 1% ITS plus 10% FBS significantly promoted cell proliferation than 10% FBS alone. No chondrocytes grew in ITS alone medium. 1% ITS plus 10% FBS enhanced cartilage formation in terms of size, wet weight, cartilage specific matrices, and homogeneity, compared to 10% FBS alone group. Furthermore, ITS prevented engineered cartilage from dedifferentiation (i.e., higher index of Col II/Col I mRNA expression and expression of aggrecan and hypertrophy (i.e., lower mRNA expression of Col X and MMP13. In conclusion, our results indicated that ITS efficiently enhanced auricular chondrocytes proliferation, retained chondrogenic phenotypes, and promoted engineered cartilage formation when combined with FBS, which is potentially used as key supplementation in auricular chondrocytes and engineered cartilage culture.

  13. The Effects of Smoking on Ultrasonographic Thickness and Elastosonographic Strain Ratio Measurements of Distal Femoral Cartilage

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    Harun R. Gungor

    2016-04-01

    Full Text Available Although adverse effects of smoking on bone health are all well known, data on how smoking interacts with cartilage structure in otherwise healthy individuals remains conflicting. Here, we ascertain the effects of cigarette smoking on sonoelastographic properties of distal femoral cartilage in asymptomatic adults. Demographic characteristics and smoking habits (packets/year of healthy volunteers were recorded. Medial, intercondylar, and lateral distal femoral cartilage thicknesses and strain ratios on the dominant extremity were measured with ultrasonography (US and real time US elastography. A total of 88 subjects (71 M, 17 F; aged 18–56 years, N = 43 smokers and N = 45 nonsmokers were evaluated. Mean amount of cigarette smoking was 10.3 ± 8.9 (1–45 packets/year. Medial, intercondylar and lateral cartilage were thicker in smokers than nonsmokers (p = 0.002, p = 0.017, and p = 0.004, respectively. Medial distal femoral cartilage strain ratio was lower in smokers (p = 0.003. The amount of smoking was positively correlated with cartilage thicknesses and negatively correlated with medial cartilage strain ratios (p < 0.05. Femoral cartilage is thicker in smokers but has less strain ratio representing harder cartilage on the medial side. Future studies are needed to understand how these structural changes in the knee cartilage should be interpreted with regard to the development of knee osteoarthritis in smokers.

  14. The Effects of Smoking on Ultrasonographic Thickness and Elastosonographic Strain Ratio Measurements of Distal Femoral Cartilage.

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    Gungor, Harun R; Agladioglu, Kadir; Akkaya, Nuray; Akkaya, Semih; Ok, Nusret; Ozçakar, Levent

    2016-04-01

    Although adverse effects of smoking on bone health are all well known, data on how smoking interacts with cartilage structure in otherwise healthy individuals remains conflicting. Here, we ascertain the effects of cigarette smoking on sonoelastographic properties of distal femoral cartilage in asymptomatic adults. Demographic characteristics and smoking habits (packets/year) of healthy volunteers were recorded. Medial, intercondylar, and lateral distal femoral cartilage thicknesses and strain ratios on the dominant extremity were measured with ultrasonography (US) and real time US elastography. A total of 88 subjects (71 M, 17 F; aged 18-56 years, N = 43 smokers and N = 45 nonsmokers) were evaluated. Mean amount of cigarette smoking was 10.3 ± 8.9 (1-45) packets/year. Medial, intercondylar and lateral cartilage were thicker in smokers than nonsmokers (p = 0.002, p = 0.017, and p = 0.004, respectively). Medial distal femoral cartilage strain ratio was lower in smokers (p = 0.003). The amount of smoking was positively correlated with cartilage thicknesses and negatively correlated with medial cartilage strain ratios (p < 0.05). Femoral cartilage is thicker in smokers but has less strain ratio representing harder cartilage on the medial side. Future studies are needed to understand how these structural changes in the knee cartilage should be interpreted with regard to the development of knee osteoarthritis in smokers. PMID:27110800

  15. Kartogenin induces cartilage-like tissue formation in tendon–bone junction

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    Zhang, Jianying; Wang, James H-C

    2014-01-01

    Tendon–bone junctions (TBJs) are frequently injured, especially in athletic settings. Healing of TBJ injuries is slow and is often repaired with scar tissue formation that compromises normal function. This study explored the feasibility of using kartogenin (KGN), a biocompound, to enhance the healing of injured TBJs. We first determined the effects of KGN on the proliferation and chondrogenic differentiation of rabbit bone marrow stromal cells (BMSCs) and patellar tendon stem/progenitor cells (PTSCs) in vitro. KGN enhanced cell proliferation in both cell types in a concentration-dependent manner and induced chondrogenic differentiation of stem cells, as demonstrated by high expression levels of chondrogenic markers aggrecan, collagen II and Sox-9. Besides, KGN induced the formation of cartilage-like tissues in cell cultures, as observed through the staining of abundant proteoglycans, collagen II and osteocalcin. When injected into intact rat patellar tendons in vivo, KGN induced cartilage-like tissue formation in the injected area. Similarly, when KGN was injected into experimentally injured rat Achilles TBJs, wound healing in the TBJs was enhanced, as evidenced by the formation of extensive cartilage-like tissues. These results suggest that KGN may be used as an effective cell-free clinical therapy to enhance the healing of injured TBJs. PMID:25419468

  16. Kartogenin induces cartilage-like tissue formation in tendon-bone junction

    Institute of Scientific and Technical Information of China (English)

    Jianying Zhang; James H-C Wang

    2014-01-01

    Tendon-bone junctions (TBJs) are frequently injured, especially in athletic settings. Healing of TBJ injuries is slow and is often repaired with scar tissue formation that compromises normal function. This study explored the feasibility of using kartogenin (KGN), a biocompound, to enhance the healing of injured TBJs. We first determined the effects of KGN on the proliferation and chondrogenic differentiation of rabbit bone marrow stromal cells (BMSCs) and patellar tendon stem/progenitor cells (PTSCs) in vitro. KGN enhanced cell proliferation in both cell types in a concentration-dependent manner and induced chondrogenic differentiation of stem cells, as demonstrated by high expression levels of chondrogenic markers aggrecan, collagen II and Sox-9. Besides, KGN induced the formation of cartilage-like tissues in cell cultures, as observed through the staining of abundant proteoglycans, collagen II and osteocalcin. When injected into intact rat patellar tendons in vivo, KGN induced cartilage-like tissue formation in the injected area. Similarly, when KGN was injected into experimentally injured rat Achilles TBJs, wound healing in the TBJs was enhanced, as evidenced by the formation of extensive cartilage-like tissues. These results suggest that KGN may be used as an effective cell-free clinical therapy to enhance the healing of injured TBJs.

  17. Kartogenin induces cartilage-like tissue formation in tendon-bone junction.

    Science.gov (United States)

    Zhang, Jianying; Wang, James H-C

    2014-01-01

    Tendon-bone junctions (TBJs) are frequently injured, especially in athletic settings. Healing of TBJ injuries is slow and is often repaired with scar tissue formation that compromises normal function. This study explored the feasibility of using kartogenin (KGN), a biocompound, to enhance the healing of injured TBJs. We first determined the effects of KGN on the proliferation and chondrogenic differentiation of rabbit bone marrow stromal cells (BMSCs) and patellar tendon stem/progenitor cells (PTSCs) in vitro. KGN enhanced cell proliferation in both cell types in a concentration-dependent manner and induced chondrogenic differentiation of stem cells, as demonstrated by high expression levels of chondrogenic markers aggrecan, collagen II and Sox-9. Besides, KGN induced the formation of cartilage-like tissues in cell cultures, as observed through the staining of abundant proteoglycans, collagen II and osteocalcin. When injected into intact rat patellar tendons in vivo, KGN induced cartilage-like tissue formation in the injected area. Similarly, when KGN was injected into experimentally injured rat Achilles TBJs, wound healing in the TBJs was enhanced, as evidenced by the formation of extensive cartilage-like tissues. These results suggest that KGN may be used as an effective cell-free clinical therapy to enhance the healing of injured TBJs. PMID:25419468

  18. A Validated Model of the Pro- and Anti-inflammatory Cytokine Balancing Act in Articular Cartilage Lesion Formation

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    Xiayi eWang

    2015-03-01

    Full Text Available Traumatic injuries of articular cartilage result in the formation of a cartilage lesion and contribute to cartilage degeneration and the risk of osteoarthritis (OA. A better understanding of the framework for the formation of a cartilage lesion formation would be helpful in therapy development. Towards this end, we present an age and space-structured model of articular cartilage lesion formation after a single blunt impact. This model modifies the reaction-diffusion-delay models in Graham et al. (2012 (single impact and Wang et al. (2014 (cyclic loading, focusing on the balancing act' between pro- and anti-inflammatory cytokines. Age structure is introduced to replace the delay terms for cell transitions used in these earlier models; we find age structured models to be more flexible in representing the underlying biological system and more tractable computationally. Numerical results show a successful capture of chondrocyte behavior and chemical activities associated with the cartilage lesion after the initial injury; experimental validation of our computational results is presented. We anticipate that our in silico model of cartilage damage from a single blunt impact can be used to provide information that may not be easily obtained through in in vivo or in vitro studies.

  19. Transforming growth factor beta signaling is essential for the autonomous formation of cartilage-like tissue by expanded chondrocytes.

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    Adel Tekari

    Full Text Available Cartilage is a tissue with limited self-healing potential. Hence, cartilage defects require surgical attention to prevent or postpone the development of osteoarthritis. For cell-based cartilage repair strategies, in particular autologous chondrocyte implantation, articular chondrocytes are isolated from cartilage and expanded in vitro to increase the number of cells required for therapy. During expansion, the cells lose the competence to autonomously form a cartilage-like tissue, that is in the absence of exogenously added chondrogenic growth factors, such as TGF-βs. We hypothesized that signaling elicited by autocrine and/or paracrine TGF-β is essential for the formation of cartilage-like tissue and that alterations within the TGF-β signaling pathway during expansion interfere with this process. Primary bovine articular chondrocytes were harvested and expanded in monolayer culture up to passage six and the formation of cartilage tissue was investigated in high density pellet cultures grown for three weeks. Chondrocytes expanded for up to three passages maintained the potential for autonomous cartilage-like tissue formation. After three passages, however, exogenous TGF-β1 was required to induce the formation of cartilage-like tissue. When TGF-β signaling was blocked by inhibiting the TGF-β receptor 1 kinase, the autonomous formation of cartilage-like tissue was abrogated. At the initiation of pellet culture, chondrocytes from passage three and later showed levels of transcripts coding for TGF-β receptors 1 and 2 and TGF-β2 to be three-, five- and five-fold decreased, respectively, as compared to primary chondrocytes. In conclusion, the autonomous formation of cartilage-like tissue by expanded chondrocytes is dependent on signaling induced by autocrine and/or paracrine TGF-β. We propose that a decrease in the expression of the chondrogenic growth factor TGF-β2 and of the TGF-β receptors in expanded chondrocytes accounts for a decrease

  20. Competition between Jagged-Notch and Endothelin1 Signaling Selectively Restricts Cartilage Formation in the Zebrafish Upper Face

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    Barske, Lindsey; Askary, Amjad; Zuniga, Elizabeth; Balczerski, Bartosz; Bump, Paul; Nichols, James T.; Crump, J. Gage

    2016-01-01

    The intricate shaping of the facial skeleton is essential for function of the vertebrate jaw and middle ear. While much has been learned about the signaling pathways and transcription factors that control facial patterning, the downstream cellular mechanisms dictating skeletal shapes have remained unclear. Here we present genetic evidence in zebrafish that three major signaling pathways − Jagged-Notch, Endothelin1 (Edn1), and Bmp − regulate the pattern of facial cartilage and bone formation by controlling the timing of cartilage differentiation along the dorsoventral axis of the pharyngeal arches. A genomic analysis of purified facial skeletal precursors in mutant and overexpression embryos revealed a core set of differentiation genes that were commonly repressed by Jagged-Notch and induced by Edn1. Further analysis of the pre-cartilage condensation gene barx1, as well as in vivo imaging of cartilage differentiation, revealed that cartilage forms first in regions of high Edn1 and low Jagged-Notch activity. Consistent with a role of Jagged-Notch signaling in restricting cartilage differentiation, loss of Notch pathway components resulted in expanded barx1 expression in the dorsal arches, with mutation of barx1 rescuing some aspects of dorsal skeletal patterning in jag1b mutants. We also identified prrx1a and prrx1b as negative Edn1 and positive Bmp targets that function in parallel to Jagged-Notch signaling to restrict the formation of dorsal barx1+ pre-cartilage condensations. Simultaneous loss of jag1b and prrx1a/b better rescued lower facial defects of edn1 mutants than loss of either pathway alone, showing that combined overactivation of Jagged-Notch and Bmp/Prrx1 pathways contribute to the absence of cartilage differentiation in the edn1 mutant lower face. These findings support a model in which Notch-mediated restriction of cartilage differentiation, particularly in the second pharyngeal arch, helps to establish a distinct skeletal pattern in the upper

  1. Ultrasonographic measurement of the femoral cartilage thickness in patients with occupational lead exposure.

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    Yıldızgören, Mustafa T; Baki, Ali E; Kara, Murat; Ekiz, Timur; Tiftik, Tülay; Tutkun, Engin; Yılmaz, Hınç; Özçakar, Levent

    2015-01-01

    The objective of the present study is to compare distal femoral cartilage thicknesses of patients with occupational lead exposure with those of healthy subjects by using ultrasonography. A total of 48 male workers (a mean age of 34.8±6.8 years and mean body mass index (BMI) of 25.8±3.1 kg/m(2)) with a likely history of occupational lead exposure and age- and BMI-matched healthy male subjects were enrolled. Demographic and clinical characteristics of the patients, that is, age, weight, height, occupation, estimated duration of lead exposure, and smoking habits were recorded. Femoral cartilage thickness was assessed from the midpoints of right medial condyle (RMC), right lateral condyle (RLC), right intercondylar area (RIA), left medial condyle (LMC), left lateral condyle (LLC), and left intercondylar area (LIA) by using ultrasonography. Although the workers had higher femoral cartilage thickness values at all measurement sites when compared with those of the control subjects, the difference reached statistical significance at RLC (P=0.010), LMC (P=0.001), and LIA (P=0.039). There were no correlations between clinical parameters and cartilage-thickness values of the workers. Subjects with a history of lead exposure had higher femoral cartilage thickness as compared with the healthy subjects. Further studies, including histological evaluations, are awaited to clarify the clinical relevance of this increase in cartilage thickness and to explore the long-term follow-up especially with respect to osteoarthritis development.

  2. Ultrasound and MRI measurements of joint cartilage in healthy children. A validation study

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    Spannow, A H; Stenboeg, E; Jensen, Mogens Pfeiffer;

    2011-01-01

    measurements of cartilage thickness in target joints in healthy children by comparing them with MRI. Materials and Methods: Twenty-five healthy Caucasian children (17 boys/ 8 girls), mean age 11.33 years, were examined with MRI (1.5 T, fat-suppressed T 1-weighted 3D sequences) and US (real-time Hitachi EUB...... 6500 CFM, B-mode 6 - 14 MHz linear transducer) in the right knee, ankle, wrist, metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints. US was obtained according to the EULAR standard scans. Results: All differences in cartilage thickness measurements between MRI and US were less than 0.......5 millimeters. The coefficient of variation (CV) was found to be good (16 %) except for in the case of the wrist joint (20 %). Conclusion: We found a good level of agreement and no significant systematic joint size-related differences in cartilage thickness measurements between MRI and US. US appears to be a...

  3. Deginerative changes of femoral articular cartilage in the knee : comparative study of specimen sonography and pathology

    International Nuclear Information System (INIS)

    To determine the sonographic findings of degenerative change in femoral articular cartilage of the knee by comparative study of specimen sonography and pathology. We obtained 40 specimens of cartilage of the femur (20 medial and 20 lateral condylar) from 20 patients with osteoarthritis of the knee who had undergone total knee replacement. The specimens were placed in a saline-filled container and sonography was performed using a 10-MHz linear transducer. Sonographic abnormalities were evaluated at the cartilage surface, within the cartilage, and at the bone-cartilage interface, and were compared with the corresponding pathologic findings. In addition, cartilage thickness was measured at a representative portion of each femoral cartilage specimen and was compared with the thickness determined by sonography. 'Dot' lesions, irregularity or loss of the hyperechoic line, were demonstrated by sonography at the saline-cartilage interface of 14 cartilages. Pathologic examination showed that these findings corresponded to cleft, detachment, erosion, and degeneration. Irregularities in the hyperechoic line at the bone-cartilage interface were revealed by sonography in eight cartilages and were related to irregularity or loss of tidemark, downward displacement of the cartilage, and subchondral callus formation. Dot lesions, corresponding to cleft and degeneration, were noted within one cartilage. Cartilage thickness measured on specimen and by sonography showed no significant difference (p=0.446). Specimen sonography suggested that articular cartilage underwent degenerative histopathological change. Cartilage thickness measured by sonography exactly reflected real thickness

  4. Influence of Cartilage Extracellular Matrix Molecules on Cell Phenotype and Neocartilage Formation

    OpenAIRE

    Grogan, Shawn P.; Chen, Xian; Sovani, Sujata; Taniguchi, Noboru; Colwell, Clifford W.; Lotz, Martin K; D'Lima, Darryl D

    2013-01-01

    Interaction between chondrocytes and the cartilage extracellular matrix (ECM) is essential for maintaining the cartilage's role as a low-friction and load-bearing tissue. In this study, we examined the influence of cartilage zone-specific ECM on human articular chondrocytes (HAC) in two-dimensional and three-dimensional (3D) environments. Two culture systems were used. SYSTEM 1: HAC were cultured on cell-culture plates that had been precoated with the following ECM molecules for 7 days: decor...

  5. Cartilage signal intensity on T1-weighted MRI: association with risk factors and measures of knee osteoarthritis.

    Science.gov (United States)

    Stannus, Oliver Patrick; Jiang, Danchi; Cicuttini, Flavia; Cao, Yuelong; Ding, Changhai

    2014-03-01

    This study aims to assess mean signal intensity of cartilage on T1-weighted magnetic resonance imaging (MRI) images, and then examine whether mean signal intensity is associated with risk factors and measures of osteoarthritis in younger and older adults. A total of 50 younger adult subjects (mean age 41, range 29-57; 64% female; baseline only) and 168 older adult subjects (mean age 63, range 52-78; 46% female; baseline and 2.9 year followup) were randomly selected from the community. T1-weighted fat-supressed gradient recall echo MRI scans of right knees were performed. Image segmentation was performed semi-automatically, and measures of mean signal intensity and cartilage thickness for regions of cartilage were obtained. Urinary levels of C-terminal crosslinking telopeptide of type II collagen (U-CTX-II) were measured in younger adults. Cartilage defects were scored using a 5-point scale in both groups. In multivariable analyses, higher cartilage defects and BMI were significantly associated with lower same-region mean signal intensity in younger and older adults. CTX-II was negatively and significantly associated with mean signal intensity of cartilage in the lateral femoral and patellar sites. Joint space narrowing and osteophytes analysed in older adults were significantly associated with reduced mean signal intensity at various sites. Over 2.9 years, lower mean signal intensity at femoral and patellar sites and in whole knee was associated with decreases in cartilage thickness. Reduced mean signal intensity of cartilage on T1-weighted gradient recall echo MRI is associated with osteoarthritis risk factors and predicts cartilage loss suggesting low cartilage signal intensity may reflect early osteoarthritic changes. PMID:24322833

  6. Processed bovine cartilage: an improved biosynthetic implant for contour defects

    Energy Technology Data Exchange (ETDEWEB)

    Ersek, R.A.; Hart, W.G. Jr.; Greer, D.; Beisang, A.A.; Flynn, P.J.; Denton, D.R.

    1984-05-01

    Irradiated human cartilage has been found to be a superior implant material for correction of contour defects; however, availability problems have prevented this material from gaining wide acceptance. Implantation of processed irradiated bovine cartilage in primates and rabbits, as described here, provides strong evidence that this material performs like irradiated allograft cartilage antigenically and has certain cosmetic advantages over allograft cartilage. Our studies in primates have shown that there is no systemically measurable antibody-antigen reaction, either cellular or noncellular, to irradiated processed bovine cartilage. Neither primary nor second-set provocative implantations produced any measurable rejection. In rabbits, composite grafts of two pieces of irradiated bovine cartilage adjacent to each other were also well tolerated, with no measurable absorption and with capsule formation typical of a foreign body reaction to an inert object.

  7. Reproducibility and accuracy of quantitative assessment of articular cartilage volume measurements with 3.0 tesla magnetic resonance imaging

    Institute of Scientific and Technical Information of China (English)

    XING Wei; SHENG Jing; CHEN Wen-hua; TIAN Jian-ming; ZHANG Li-rong; WANG Dong-qing

    2011-01-01

    Background Quantitative magnetic resonance imaging (qMRI) of articular cartilage represents a powerful tool in osteoarthritis research, but has so far been confined to a field strength of 1.5 T. The aim of the study was to determine the reproducibility and accuracy of qMRI assessments of the knee cartilage volume by comparing quantitative swine cartilage volumes of the sagittal (sag) multi echo data imagine combination water-excitation (MEDICwe) sequence and the fast low-angle shoot water-excitation (FLASHwe) sequence at 3.0-T MRI to directly measured volumes (DMV) of the surgically removed articular cartilage.Methods Test-retest MRI was acquired in 20 swine knees. Two sag FLASHwe sequences and two sag MEDICwe sequences (spatial resolution 0.4 mm × 0.4 mm × 1.0 mm of 3-dimension (3D) were acquired at 3-T MRI in a knee.Articular cartilage volume was calculated from 3D reformations of the MRI by using a manual program. Calculated volumes were compared with DMV of the surgically removed articular cartilage. Knee joint cartilage plates were quantified paired in order.Results In the knee joint of swine, reproducibility errors (paired analysis) for cartilage volume were 2.5% to 3.2% with sag FLASHwe, and 1.6% to 3.0% with sag MEDICwe. Correlation coefficients between results obtained with qMRI and DMV ranged from 0.90 to 0.98 for cartilage volume. Systematic pairwise difference between results obtained with qMRI and DMV ranged from -1.1% to 2.8%. Random pairwise differences between results obtained with qMRI and DMV ranged from (2.9 ±2.4)% to (6.8±4.5)%.Conclusions FLASHwe and MEDICwe sequences permit highly accurate and reproducible analysis of cartilage volume in the knee joints of swine at 3-T MRI. Cartilage volume reproducibility for the MEDICwe data is slightly higher than the FLASHwe data.

  8. Knockdown of the cell cycle inhibitor p21 enhances cartilage formation by induced pluripotent stem cells.

    Science.gov (United States)

    Diekman, Brian O; Thakore, Pratiksha I; O'Connor, Shannon K; Willard, Vincent P; Brunger, Jonathan M; Christoforou, Nicolas; Leong, Kam W; Gersbach, Charles A; Guilak, Farshid

    2015-04-01

    The limited regenerative capacity of articular cartilage contributes to progressive joint dysfunction associated with cartilage injury or osteoarthritis. Cartilage tissue engineering seeks to provide a biological substitute for repairing damaged or diseased cartilage, but requires a cell source with the capacity for extensive expansion without loss of chondrogenic potential. In this study, we hypothesized that decreased expression of the cell cycle inhibitor p21 would enhance the proliferative and chondrogenic potential of differentiated induced pluripotent stem cells (iPSCs). Murine iPSCs were directed to differentiate toward the chondrogenic lineage with an established protocol and then engineered to express a short hairpin RNA (shRNA) to reduce the expression of p21. Cells expressing the p21 shRNA demonstrated higher proliferative potential during monolayer expansion and increased synthesis of glycosaminoglycans (GAGs) in pellet cultures. Furthermore, these cells could be expanded ∼150-fold over three additional passages without a reduction in the subsequent production of GAGs, while control cells showed reduced potential for GAG synthesis with three additional passages. In pellets from extensively passaged cells, knockdown of p21 attenuated the sharp decrease in cell number that occurred in control cells, and immunohistochemical analysis showed that p21 knockdown limited the production of type I and type X collagen while maintaining synthesis of cartilage-specific type II collagen. These findings suggest that manipulating the cell cycle can augment the monolayer expansion and preserve the chondrogenic capacity of differentiated iPSCs, providing a strategy for enhancing iPSC-based cartilage tissue engineering.

  9. Growth plate regulation and osteochondroma formation: insights from tracing proteoglycans in zebrafish models and human cartilage.

    Science.gov (United States)

    de Andrea, Carlos E; Prins, Frans A; Wiweger, Malgorzata I; Hogendoorn, Pancras C W

    2011-06-01

    Proteoglycans are secreted into the extracellular matrix of virtually all cell types and function in several cellular processes. They consist of a core protein onto which glycosaminoglycans (e.g., heparan or chondroitin sulphates), are attached. Proteoglycans are important modulators of gradient formation and signal transduction. Impaired biosynthesis of heparan sulphate glycosaminoglycans causes osteochondroma, the most common bone tumour to occur during adolescence. Cytochemical staining with positively charged dyes (e.g., polyethyleneimine-PEI) allows, visualisation of proteoglycans and provides a detailed description of how proteoglycans are distributed throughout the cartilage matrix. PEI staining was studied by electron and reflection contrast microscopy in human growth plates, osteochondromas and five different proteoglycan-deficient zebrafish mutants displaying one of the following skeletal phenotypes: dackel (dak/ext2), lacking heparan sulphate and identified as a model for human multiple osteochondromas; hi307 (β3gat3), deficient for most glycosaminoglycans; pinscher (pic/slc35b2), presenting with defective sulphation of glycosaminoglycans; hi954 (uxs1), lacking most glycosaminoglycans; and knypek (kny/gpc4), missing the protein core of the glypican-4 proteoglycan. The panel of genetically well-characterized proteoglycan-deficient zebrafish mutants serves as a convincing and comprehensive study model to investigate proteoglycan distribution and the relation of this distribution to the model mutation status. They also provide insight into the distributions and gradients that can be expected in the human homologue. Human growth plate, wild-type zebrafish and fish mutants with mild proteoglycan defects (hi307 and kny) displayed proteoglycans distributed in a gradient throughout the matrix. Although the mutants pic and hi954, which had severely impaired proteoglycan biosynthesis, showed no PEI staining, dak mutants demonstrated reduced PEI staining and no

  10. Accuracy of model-based tracking of knee kinematics and cartilage contact measured by dynamic volumetric MRI.

    Science.gov (United States)

    Kaiser, Jarred; Monawer, Arezu; Chaudhary, Rajeev; Johnson, Kevin M; Wieben, Oliver; Kijowski, Richard; Thelen, Darryl G

    2016-10-01

    The purpose of this study was to determine the accuracy of knee kinematics and cartilage contact measured by volumetric dynamic MRI. A motor-actuated phantom drove femoral and tibial bone segments through cyclic 3D motion patterns. Volumetric images were continuously acquired using a 3D radially undersampled cine spoiled gradient echo sequence (SPGR-VIPR). Image data was binned based on position measured via a MRI-compatible rotary encoder. High-resolution static images were segmented to create bone models. Model-based tracking was performed by optimally registering the bone models to the volumetric images at each frame of the SPGR-VIPR series. 3D tibiofemoral translations and orientations were reconstructed, and compared to kinematics obtained by tracking fiducial markers. Imaging was repeated on a healthy subject who performed cyclic knee flexion-extension. Cartilage contact for the subject was assessed by measuring the overlap between articular cartilage surfaces. Model-based tracking was able to track tibiofemoral angles and translations with precisions less than 0.8° and 0.5mm. These precisions resulted in an uncertainty of less than 0.5mm in cartilage contact location. Dynamic SPGR-VIPR imaging can accurately assess in vivo knee kinematics and cartilage contact during voluntary knee motion performed in a MRI scanner. This technology could facilitate the quantitative investigation of links between joint mechanics and the development of osteoarthritis. PMID:27387902

  11. Accuracy of model-based tracking of knee kinematics and cartilage contact measured by dynamic volumetric MRI.

    Science.gov (United States)

    Kaiser, Jarred; Monawer, Arezu; Chaudhary, Rajeev; Johnson, Kevin M; Wieben, Oliver; Kijowski, Richard; Thelen, Darryl G

    2016-10-01

    The purpose of this study was to determine the accuracy of knee kinematics and cartilage contact measured by volumetric dynamic MRI. A motor-actuated phantom drove femoral and tibial bone segments through cyclic 3D motion patterns. Volumetric images were continuously acquired using a 3D radially undersampled cine spoiled gradient echo sequence (SPGR-VIPR). Image data was binned based on position measured via a MRI-compatible rotary encoder. High-resolution static images were segmented to create bone models. Model-based tracking was performed by optimally registering the bone models to the volumetric images at each frame of the SPGR-VIPR series. 3D tibiofemoral translations and orientations were reconstructed, and compared to kinematics obtained by tracking fiducial markers. Imaging was repeated on a healthy subject who performed cyclic knee flexion-extension. Cartilage contact for the subject was assessed by measuring the overlap between articular cartilage surfaces. Model-based tracking was able to track tibiofemoral angles and translations with precisions less than 0.8° and 0.5mm. These precisions resulted in an uncertainty of less than 0.5mm in cartilage contact location. Dynamic SPGR-VIPR imaging can accurately assess in vivo knee kinematics and cartilage contact during voluntary knee motion performed in a MRI scanner. This technology could facilitate the quantitative investigation of links between joint mechanics and the development of osteoarthritis.

  12. Engineering Cartilage

    Science.gov (United States)

    ... Research Matters NIH Research Matters March 3, 2014 Engineering Cartilage Artistic rendering of human stem cells on ... situations has been a major goal in tissue engineering. Cartilage contains water, collagen, proteoglycans, and chondrocytes. Collagens ...

  13. Automating measurement of subtle changes in articular cartilage from MRI of the knee by combining 3D image registration and segmentation

    Science.gov (United States)

    Lynch, John A.; Zaim, Souhil; Zhao, Jenny; Peterfy, Charles G.; Genant, Harry K.

    2001-07-01

    In osteoarthritis, articular cartilage loses integrity and becomes thinned. This usually occurs at sites which bear weight during normal use. Measurement of such loss from MRI scans, requires precise and reproducible techniques, which can overcome the difficulties of patient repositioning within the scanner. In this study, we combine a previously described technique for segmentation of cartilage from MRI of the knee, with a technique for 3D image registration that matches localized regions of interest at followup and baseline. Two patients, who had recently undergone meniscal surgery, and developed lesions during the 12 month followup period were examined. Image registration matched regions of interest (ROI) between baseline and followup, and changes within the cartilage lesions were estimate to be about a 16% reduction in cartilage volume within each ROI. This was more than 5 times the reproducibility of the measurement, but only represented a change of between 1 and 2% in total femoral cartilage volume. Changes in total cartilage volume may be insensitive for quantifying changes in cartilage morphology. A combined used of automated image segmentation, with 3D image registration could be a useful tool for the precise and sensitive measurement of localized changes in cartilage from MRI of the knee.

  14. First shark from the Late Devonian (Frasnian Gogo Formation, Western Australia sheds new light on the development of tessellated calcified cartilage.

    Directory of Open Access Journals (Sweden)

    John A Long

    Full Text Available Living gnathostomes (jawed vertebrates comprise two divisions, Chondrichthyes (cartilaginous fishes, including euchondrichthyans with prismatic calcified cartilage, and extinct stem chondrichthyans and Osteichthyes (bony fishes including tetrapods. Most of the early chondrichthyan ('shark' record is based upon isolated teeth, spines, and scales, with the oldest articulated sharks that exhibit major diagnostic characters of the group--prismatic calcified cartilage and pelvic claspers in males--being from the latest Devonian, c. 360 Mya. This paucity of information about early chondrichthyan anatomy is mainly due to their lack of endoskeletal bone and consequent low preservation potential.Here we present new data from the first well-preserved chondrichthyan fossil from the early Late Devonian (ca. 380-384 Mya Gogo Formation Lägerstatte of Western Australia. The specimen is the first Devonian shark body fossil to be acid-prepared, revealing the endoskeletal elements as three-dimensional undistorted units: Meckel's cartilages, nasal, ceratohyal, basibranchial and possible epibranchial cartilages, plus left and right scapulocoracoids, as well as teeth and scales. This unique specimen is assigned to Gogoselachus lynnbeazleyae n. gen. n. sp.The Meckel's cartilages show a jaw articulation surface dominated by an expansive cotylus, and a small mandibular knob, an unusual condition for chondrichthyans. The scapulocoracoid of the new specimen shows evidence of two pectoral fin basal articulation facets, differing from the standard condition for early gnathostomes which have either one or three articulations. The tooth structure is intermediate between the 'primitive' ctenacanthiform and symmoriiform condition, and more derived forms with a euselachian-type base. Of special interest is the highly distinctive type of calcified cartilage forming the endoskeleton, comprising multiple layers of nonprismatic subpolygonal tesserae separated by a cellular matrix

  15. Experimental issues in the measurement of multi-component relaxation times in articular cartilage by microscopic MRI

    Science.gov (United States)

    Wang, Nian; Xia, Yang

    2013-10-01

    A number of experimental issues in the measurement of multi-component T2 and T1ρ relaxations in native and enzymatically digested articular cartilage were investigated by microscopic MRI (μMRI). The issues included the bath solutions (physiological saline and phosphate buffered saline (PBS)), the imaging resolution (35-140 μm), the specimen orientations (0° and 55°), and the strength of spin-lock frequencies (0.5-2 kHz) in the T1ρ experiments. In addition to cartilage, the samples of agar gel and doped water solution were also used in the investigation. Two imaging sequences were used: CPMG-SE and MSME. All raw data were analyzed by the non-negative least square (NNLS) method. The MSME sequence was shown to result in the observation of multi-component T2, even in the gel and liquid samples, demonstrating the artificial uncleanness of this sequence in the multi-component measurements. The soaking of cartilage in PBS reduced the observable T2 components to one at both 0° and 55°, suggesting the effect of phosphate ions on proton exchange between different pools of water molecules. The cartilage orientation with respect to the external magnetic field and the spin-lock strengths in the T1ρ experiment both affected the quantification of the multi-component relaxation. The transitions between a mono-component and multi-components in cartilage under various experimental conditions call for the extra caution in interpreting the relaxation results.

  16. TGF-ß in osteoarthritis : age-related loss of protective function in cartilage and player in osteophyte formation and synovial fibrosis

    NARCIS (Netherlands)

    Blaney Davidson, Esmeralda Nicole

    2007-01-01

    Osteoarthritis (OA) is a common joint disease affecting mainly the elderly population. In younger people it can be caused by joint trauma or congenital afflictions. OA is characterized by cartilage damage, synovial fibrosis and osteophyte formation. TGF-ß is a growth factor that is a potent inducer

  17. Measurement of articular cartilage volumes in the normal knee by magnetic resonance imaging. Can cartilage volumes be estimated from physical characteristics?

    International Nuclear Information System (INIS)

    In recent times several studies have been performed on magnetic resonance imaging (MRI) sequences for imaging cartilage. A fat-suppressed three-dimensional sequence is one such noteworthy example. More recent studies have reported that the total volume of cartilage in a knee joint can be elucidated using this sequence. Based on these studies, we hypothesized that the total volume of cartilage in the knee joint may reflect certain other physical characteristics. The purpose of the current study was to clarify the articular cartilage volumes of the patella and femur in the human knee joints of healthy adults using MRI and to analyze the correlation of these volumes with other physical characteristics. The material comprised 68 knees of 68 Japanese healthy volunteers, aged from their twenties to their forties (37 men and 31 women) who had no past history of joint disease or trauma in the legs. The knees were imaged by MRI with a fat-suppressed three-dimensional sequence, and the cartilage volumes were calculated by computer processing. The factors analyzed were age, body weight, height, leg length, foot size, circumferences of the thigh and lower leg, the distance between medial and lateral femoral condyles, the diameter of the tibial head, body mass index, general joint laxity, quadriceps angle, and leg-heel alignment. The mean cartilage volume was 7.6±1.6 cm3 (8.3±1.6 cm3 in men, 6.7±0.9 cm3 in women). It was significantly larger in men than in women. However, the volume positively correlated with body weight, height, leg length, and foot size, without distinction of gender or age. Based on these data, a multiple regression analysis was developed: cartilage volume 0.113 x height-11.053. We concluded that the cartilage volume depends on physical size regardless of gender, and it can be estimated from factors of physical size. (author)

  18. Vessel formation is induced prior to the appearance of cartilage in BMP-2-mediated heterotopic ossification

    Science.gov (United States)

    Heterotopic ossification (HO), or endochondral bone formation at nonskeletal sites, often results from traumatic injury and can lead to devastating consequences. Alternatively, the ability to harness this phenomenon would greatly enhance current orthopedic tools for treating segmental bone defects. ...

  19. Comprehensive Profiling of Cartilage Extracellular Matrix Formation and Maturation Using Sequential Extraction and Label-free Quantitative Proteomics*

    OpenAIRE

    Wilson, Richard; Diseberg, Anders F.; Gordon, Lavinia; Zivkovic, Snezana; Tatarczuch, Liliana; Mackie, Eleanor J.; Gorman, Jeffrey J.; Bateman, John F.

    2010-01-01

    Articular cartilage is indispensable for joint function but has limited capacity for self-repair. Engineering of neocartilage in vitro is therefore a major target for autologous cartilage repair in arthritis. Previous analysis of neocartilage has targeted cellular organization and specific molecular components. However, the complexity of extracellular matrix (ECM) development in neocartilage has not been investigated by proteomics. To redress this, we developed a mouse neocartilage culture sy...

  20. Kartogenin induces cartilage-like tissue formation in tendon–bone junction

    OpenAIRE

    Zhang, Jianying; Wang, James H-C.

    2014-01-01

    Tendon–bone junctions (TBJs) are frequently injured, especially in athletic settings. Healing of TBJ injuries is slow and is often repaired with scar tissue formation that compromises normal function. This study explored the feasibility of using kartogenin (KGN), a biocompound, to enhance the healing of injured TBJs. We first determined the effects of KGN on the proliferation and chondrogenic differentiation of rabbit bone marrow stromal cells (BMSCs) and patellar tendon stem/progenitor cells...

  1. Comprehensive profiling of cartilage extracellular matrix formation and maturation using sequential extraction and label-free quantitative proteomics.

    Science.gov (United States)

    Wilson, Richard; Diseberg, Anders F; Gordon, Lavinia; Zivkovic, Snezana; Tatarczuch, Liliana; Mackie, Eleanor J; Gorman, Jeffrey J; Bateman, John F

    2010-06-01

    Articular cartilage is indispensable for joint function but has limited capacity for self-repair. Engineering of neocartilage in vitro is therefore a major target for autologous cartilage repair in arthritis. Previous analysis of neocartilage has targeted cellular organization and specific molecular components. However, the complexity of extracellular matrix (ECM) development in neocartilage has not been investigated by proteomics. To redress this, we developed a mouse neocartilage culture system that produces a cartilaginous ECM. Differential analysis of the tissue proteome of 3-week neocartilage and 3-day postnatal mouse cartilage using solubility-based protein fractionation targeted components involved in neocartilage development, including ECM maturation. Initially, SDS-PAGE analysis of sequential extracts revealed the transition in protein solubility from a high proportion of readily soluble (NaCl-extracted) proteins in juvenile cartilage to a high proportion of poorly soluble (guanidine hydrochloride-extracted) proteins in neocartilage. Label-free quantitative mass spectrometry (LTQ-Orbitrap) and statistical analysis were then used to filter three significant protein groups: proteins enriched according to extraction condition, proteins differentially abundant between juvenile cartilage and neocartilage, and proteins with differential solubility properties between the two tissue types. Classification of proteins differentially abundant between NaCl and guanidine hydrochloride extracts (n = 403) using bioinformatics revealed effective partitioning of readily soluble components from subunits of larger protein complexes. Proteins significantly enriched in neocartilage (n = 78) included proteins previously not reported or with unknown function in cartilage (integrin-binding protein DEL1; coiled-coil domain-containing protein 80; emilin-1 and pigment epithelium derived factor). Proteins with differential extractability between juvenile cartilage and neocartilage

  2. Functional adaptation of equine articular cartilage: The formation of regional biochemical characteristics up to age one year

    NARCIS (Netherlands)

    Brama, P.A.J.; Tekoppele, J.M.; Bank, R.A.; Barneveld, A.; Weeren, P.R. van

    2000-01-01

    Biochemical heterogeneity of cartilage within a joint is well known in mature individuals. It has recently been reported that heterogeneity for proteoglycan content and chondrocyte metabolism in sheep develops postnatally under the influence of loading. No data exist on the collagen network in gener

  3. A microstructurally based continuum model of cartilage viscoelasticity and permeability incorporating measured statistical fiber orientations.

    Science.gov (United States)

    Pierce, David M; Unterberger, Michael J; Trobin, Werner; Ricken, Tim; Holzapfel, Gerhard A

    2016-02-01

    The remarkable mechanical properties of cartilage derive from an interplay of isotropically distributed, densely packed and negatively charged proteoglycans; a highly anisotropic and inhomogeneously oriented fiber network of collagens; and an interstitial electrolytic fluid. We propose a new 3D finite strain constitutive model capable of simultaneously addressing both solid (reinforcement) and fluid (permeability) dependence of the tissue's mechanical response on the patient-specific collagen fiber network. To represent fiber reinforcement, we integrate the strain energies of single collagen fibers-weighted by an orientation distribution function (ODF) defined over a unit sphere-over the distributed fiber orientations in 3D. We define the anisotropic intrinsic permeability of the tissue with a structure tensor based again on the integration of the local ODF over all spatial fiber orientations. By design, our modeling formulation accepts structural data on patient-specific collagen fiber networks as determined via diffusion tensor MRI. We implement our new model in 3D large strain finite elements and study the distributions of interstitial fluid pressure, fluid pressure load support and shear stress within a cartilage sample under indentation. Results show that the fiber network dramatically increases interstitial fluid pressure and focuses it near the surface. Inhomogeneity in the tissue's composition also increases fluid pressure and reduces shear stress in the solid. Finally, a biphasic neo-Hookean material model, as is available in commercial finite element codes, does not capture important features of the intra-tissue response, e.g., distributions of interstitial fluid pressure and principal shear stress. PMID:26001349

  4. The development and characterization of a competitive ELISA for measuring active ADAMTS-4 in a bovine cartilage ex vivo model

    DEFF Research Database (Denmark)

    He, Yi; Zheng, Qinlong; Simonsen, Ole;

    2013-01-01

    )) in a bovine cartilage ex vivo model. We found that after stimulation with catabolic factors, the cartilage initially released high levels of aggrecanase-derived aggrecan fragments into supernatant but subsequently decreased to background levels. The level of active ADAMTS-4 released into the supernatant...

  5. Predicting knee cartilage loss using adaptive partitioning of cartilage thickness maps

    DEFF Research Database (Denmark)

    Jørgensen, Dan R.; Dam, Erik B.; Lillholm, Martin

    2013-01-01

    This study investigates whether measures of knee cartilage thickness can predict future loss of knee cartilage. A slow and a rapid progressor group was determined using longitudinal data, and anatomically aligned cartilage thickness maps were extracted from MRI at baseline. A novel machine learni...

  6. Ultrasound measurement of joint cartilage thickness in large and small joints in healthy children: a clinical pilot study assessing observer variability

    Directory of Open Access Journals (Sweden)

    Pfeiffer-Jensen Mogens

    2007-04-01

    Full Text Available Abstract Background Loss of joint cartilage is a feature of destructive disease in JIA. The cartilage of most joints can be visualized with ultrasonography (US. Our present study focuses on discriminant validity of US in children. We studied reproducibility between and within a skilled and a non-skilled investigator of US assessment of cartilage thickness in small and large joints in healthy children. Methods and results In 11 healthy children (5 girls/6 boys, aged 9.6 years (9.3–10 years, 110 joints were examined. Cartilage thickness of the right and left hip, knee, ankle, 2nd metacarpophalangeal (MCP, and 2nd proximal interphalangeal (PIP joint independently. The joints were examined twice, two days apart by a skilled and a non-skilled investigator. Mean cartilage thickness in the five joints was: hip 2.59 ± 0.41, knee 3.67 ± 0.64, ankle 1.08 ± 0.31, MCP 1.52 ± 0.27 and PIP 0.73 ± 0.15 mm. We found the same mean differences in CTh of 0.6 mm in the inter-observer part with regard of the PIP joint. Within investigators (intra-observer, the smallest mean difference of CTh was found in the MCP joint with -0.004 (skilled and 0.013 mm (non-skilled. Conclusion We found the level of agreement between observers within a 95% Confidence Interval in assessment of cartilage thickness in hip-, knee-, ankle-, MCP-, and PIP joints in healthy children. Observer variability seems not to relate to joint size but to the positioning of the joints and the transducer. These factors seem to be of major importance for reproducible US measurements. The smallest difference in measurement of cartilage thickness between observers was found in the PIP joint, and within observers in the MCP joint and it seems that using EULAR standard US guidelines is feasible for a pediatric setting. The use of US in children is promising. Studies on larger groups of children are needed to confirm the validation and variability of US in children as well as determining the smallest

  7. Tensorial electrokinetics in articular cartilage.

    Science.gov (United States)

    Reynaud, Boris; Quinn, Thomas M

    2006-09-15

    Electrokinetic phenomena contribute to biomechanical functions of articular cartilage and underlie promising methods for early detection of osteoarthritic lesions. Although some transport properties, such as hydraulic permeability, are known to become anisotropic with compression, the direction-dependence of cartilage electrokinetic properties remains unknown. Electroosmosis experiments were therefore performed on adult bovine articular cartilage samples, whereby fluid flows were driven by electric currents in directions parallel and perpendicular to the articular surface of statically compressed explants. Magnitudes of electrokinetic coefficients decreased slightly with compression (from approximately -7.5 microL/As in the range of 0-20% compression to -6.0 microL/As in the 35-50% range) consistent with predictions of microstructure-based models of cartilage material properties. However, no significant dependence on direction of the electrokinetic coupling coefficient was detected, even for conditions where the hydraulic permeability tensor is known to be anisotropic. This contrast may also be interpreted using microstructure-based models, and provides insights into structure-function relationships in cartilage extracellular matrix and physical mediators of cell responses to tissue compression. Findings support the use of relatively simple isotropic modeling approaches for electrokinetic phenomena in cartilage and related materials, and indicate that measurement of electrokinetic properties may provide particularly robust means for clinical evaluation of cartilage matrix integrity.

  8. Engineered cartilage covered ear implants for auricular cartilage reconstruction.

    Science.gov (United States)

    Lee, Sang Jin; Broda, Christopher; Atala, Anthony; Yoo, James J

    2011-02-14

    Cartilage tissues are often required for auricular tissue reconstruction. Currently, alloplastic ear-shaped medical implants composed of silicon and polyethylene are being used clinically. However, the use of these implants is often associated with complications, including inflammation, infection, erosion, and dislodgement. To overcome these limitations, we propose a system in which tissue-engineered cartilage serves as a shell that entirely covers the alloplastic implants. This study investigated whether cartilage tissue, engineered with chondrocytes and a fibrin hydrogel, would provide adequate coverage of a commercially used medical implant. To demonstrate the in vivo stability of cell-fibrin constructs, we tested variations of fibrinogen and thrombin concentration as well as cell density. After implantation, the retrieved engineered cartilage tissue was evaluated by histo- and immunohistochemical, biochemical, and mechanical analyses. Histomorphological evaluations consistently showed cartilage formation over the medical implants with the maintenance of dimensional stability. An initial cell density was determined that is critical for the production of matrix components such as glycosaminoglycans (GAG), elastin, type II collagen, and for mechanical strength. This study shows that engineered cartilage tissues are able to serve as a shell that entirely covers the medical implant, which may minimize the morbidity associated with implant dislodgement. PMID:21182236

  9. A high throughput mechanical screening device for cartilage tissue engineering.

    Science.gov (United States)

    Mohanraj, Bhavana; Hou, Chieh; Meloni, Gregory R; Cosgrove, Brian D; Dodge, George R; Mauck, Robert L

    2014-06-27

    Articular cartilage enables efficient and near-frictionless load transmission, but suffers from poor inherent healing capacity. As such, cartilage tissue engineering strategies have focused on mimicking both compositional and mechanical properties of native tissue in order to provide effective repair materials for the treatment of damaged or degenerated joint surfaces. However, given the large number design parameters available (e.g. cell sources, scaffold designs, and growth factors), it is difficult to conduct combinatorial experiments of engineered cartilage. This is particularly exacerbated when mechanical properties are a primary outcome, given the long time required for testing of individual samples. High throughput screening is utilized widely in the pharmaceutical industry to rapidly and cost-effectively assess the effects of thousands of compounds for therapeutic discovery. Here we adapted this approach to develop a high throughput mechanical screening (HTMS) system capable of measuring the mechanical properties of up to 48 materials simultaneously. The HTMS device was validated by testing various biomaterials and engineered cartilage constructs and by comparing the HTMS results to those derived from conventional single sample compression tests. Further evaluation showed that the HTMS system was capable of distinguishing and identifying 'hits', or factors that influence the degree of tissue maturation. Future iterations of this device will focus on reducing data variability, increasing force sensitivity and range, as well as scaling-up to even larger (96-well) formats. This HTMS device provides a novel tool for cartilage tissue engineering, freeing experimental design from the limitations of mechanical testing throughput.

  10. Costal cartilage measurement during rhinoplasty in Chinese female%鼻成形术中国人女性软骨体积测量

    Institute of Scientific and Technical Information of China (English)

    王艇; 杨明洁; 杜轶男; 谷红波; 张宇; 刘靓; 秦宏智

    2012-01-01

    [目的]研究多个省级地区女性国人手术中取材的第六肋软骨形态结构及解剖学参数,为进行耳鼻部整形再造时需要肋软骨移植的临床应用提供设计依据.[方法]根据从2010年11月-2011年7月的60位女性国人肋软骨移植鼻整形手术中取出的第六软骨在测量板上的照片所作的回顾性测量并进行多重逐步回归分析.[结果]数据统计结果提示,可取出的肋软骨的平均中轴曲线长度为(7.373±1.200) cm,厚度(0.911±0.093) em.软骨的厚度与年龄呈正相关,具有统计学意义(P<0.05).[结论]提供了相对较广地域范围国人女性的肋软骨数据,对需要鼻再造、复杂鼻整形及耳再造等需要肋软骨移植的手术设计提供了数据参考.%To summarize anatomy data for clinic application of 6th rib cartilage harvest from infra - mammary fold incision during rib cartilage transplant rhinoplasty of Chinese females. [ Methods ] Data are retrospectively collected and analyzed of photographs of 6th rib cartilages over measure grid plate from 60 patients of Chinese women those accept surgeries from November of 2010 to July of 2011. The mean and standard deviation of the measurement data were calculated and correlation analysis of multiple stepwise regressions was made. [ Results ] The mean and standard deviation of central line length and thickness of 6th rib cartilage were as follow: (7. 373 ?1. 200) cm and (0.911 ?. 093 ) cm. Age had a positive correlation with thickness of 6th rib cartilages with statistically significance of P < 0.05. [Conclusion] The result helps prognosis of quantities of donor rib cartilage in ear/nose plastic and reconstructive surgeries of Chinese females.

  11. Cartilage and bone malformations in the head of zebrafish (Danio rerio) embryos following exposure to disulfiram and acetic acid hydrazide

    Energy Technology Data Exchange (ETDEWEB)

    Strecker, Ruben, E-mail: Ruben.Strecker@cos.uni-heidelberg.de [Aquatic Ecology and Toxicology Section, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany); Weigt, Stefan, E-mail: stefan.weigt@merckgroup.com [Institute of Toxicology, Merck KGaA, 64293 Darmstadt (Germany); Braunbeck, Thomas, E-mail: braunbeck@uni-hd.de [Aquatic Ecology and Toxicology Section, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, D-69120 Heidelberg (Germany)

    2013-04-15

    In order to investigate teratogenic effects, especially on cartilage and bone formation, zebrafish embryos were exposed for 144 h to the dithiocarbamate pesticide disulfiram (20–320 μg/L) and acetic acid hydrazide (0.375–12 g/L), a degradation product of isoniazid. After fixation and full-mount staining, disulfiram could be shown to induce strong cartilage malformations after exposure to ≥ 80 μg/L, whereas acetic acid hydrazide caused cartilage alterations only from 1.5 g/L. Undulating notochords occurred after exposure to disulfiram even at the lowest test concentration of 20 μg/L, whereas at the two lowest concentrations of acetic acid hydrazide (0.375 and 0.75 g/L) mainly fractures of the notochord were observed. Concentrations of acetic acid hydrazide ≥ 1.5 g/L resulted in undulated notochords similar to disulfiram. Cartilages and ossifications of the cranium, including the cleithrum, were individually analyzed assessing the severity of malformation and the degree of ossification in a semi-quantitative approach. Cartilages of the neurocranium such as the ethmoid plate proved to be more stable than cartilages of the pharyngeal skeleton such as Meckel's cartilage. Hence, ossification proved significantly more susceptible than cartilage. The alterations induced in the notochord as well as in the cranium might well be of ecological relevance, since notochord malformation is likely to result in impaired swimming and cranial malformation might compromise regular food uptake. - Highlights: ► Disulfiram and acetic acid hydrazide as notochord, cartilage and bone teratogens ► Zebrafish embryos to model effects on single cartilages and bones in the head ► LC50 calculation and head length measurements after six days post-fertilization ► Lethality, head length and teratogenic effects are dose-dependent. ► Cartilages of the neurocranium are the most stable elements in the head.

  12. Cartilage (Bovine and Shark) (PDQ)

    Science.gov (United States)

    ... Ask about Your Treatment Research Cartilage (Bovine and Shark) (PDQ®)–Patient Version Overview Go to Health Professional ... 8 ). Questions and Answers About Cartilage (Bovine and Shark) What is cartilage? Cartilage is a type of ...

  13. Brand equity measurement from a formative approach

    Directory of Open Access Journals (Sweden)

    Isabel Buil

    2010-12-01

    Full Text Available Companies need to measure brand equity to make the best tactical and strategic decisions related to this intangible asset. Therefore, this paper develops a measure of brand equity using a formative approach. Unlike previous research, this study proposes a second-order formative model and empirically validates this in two countries, Spain and the United Kingdom. With this aim, in addition to carrying out an individual analysis for each country, the measurement invariance is assessed following the recent procedure suggested by Diamantopoulos and Papadopoulos (2010. Results show that brand equity construct is characterised by some variations in its composition in the countries analysed.

  14. Knee cartilage extraction and bone-cartilage interface analysis from 3D MRI data sets

    Science.gov (United States)

    Tamez-Pena, Jose G.; Barbu-McInnis, Monica; Totterman, Saara

    2004-05-01

    This works presents a robust methodology for the analysis of the knee joint cartilage and the knee bone-cartilage interface from fused MRI sets. The proposed approach starts by fusing a set of two 3D MR images the knee. Although the proposed method is not pulse sequence dependent, the first sequence should be programmed to achieve good contrast between bone and cartilage. The recommended second pulse sequence is one that maximizes the contrast between cartilage and surrounding soft tissues. Once both pulse sequences are fused, the proposed bone-cartilage analysis is done in four major steps. First, an unsupervised segmentation algorithm is used to extract the femur, the tibia, and the patella. Second, a knowledge based feature extraction algorithm is used to extract the femoral, tibia and patellar cartilages. Third, a trained user corrects cartilage miss-classifications done by the automated extracted cartilage. Finally, the final segmentation is the revisited using an unsupervised MAP voxel relaxation algorithm. This final segmentation has the property that includes the extracted bone tissue as well as all the cartilage tissue. This is an improvement over previous approaches where only the cartilage was segmented. Furthermore, this approach yields very reproducible segmentation results in a set of scan-rescan experiments. When these segmentations were coupled with a partial volume compensated surface extraction algorithm the volume, area, thickness measurements shows precisions around 2.6%

  15. Extraction and purification of cartilage-derived growth factor and measurement of growth factor activity%软骨生长因子的提取、纯化及生物活性测定

    Institute of Scientific and Technical Information of China (English)

    王吉先; 陈晓亮; 王英振; 马进峰; 崔学文; 郑洪军; 胡有谷

    2001-01-01

    500的单一条带,高度纯化的CDGF,其生物活性约1~2 ng/ml。结论肝素-琼脂糖亲合色谱反复层析,可以从鸡软骨中得到活性较高,电泳显示单一条带的CDGF。%Objective To extract and purify the cartilage-derived growth factor (CDGF) from chicken sterna cartilage and measure its activity in vitro. Methods Chicken sterna cartilage was purchased from the local poultry farm. Extraction with sodium chloride was used for the preparation of cartilage extracts. Because CDGF has a marked affinity for heparin, recycling affinity chromatography on heparin-sepharose was applied for purification of CDGF. Sodium dodecyl sulfate-polyacrylamide gel electr-ophoresis (SDS-PAGE) and silver stain visualization were used to analyze the CDGF. Growth factor activity was measured by MTT method in the culture cartilage cell. Results CDGF was found to bind tightly to columns of immobilized heparin and could be eluted with concentration of salt in the order of 1.4-1.8 mol/L NaCl, the molecular weight of CDGF was estimated to be 18500Da by SDS-PAGE.Highly purified CDGF at about 1-2 ng/ml was obtained when crude cartilage extract was applied to heparin-sepharose and the growth factor activity was recycled over hoparin-sepharose. Conclusion CDGF can be obtained from chicken sterna cartilage by heparin-affinity chromatography. It has a high growth activity in culture cartilage cell.

  16. Effects of murine recombinant interleukin 1 on synovial joints in mice: measurement of patellar cartilage metabolism and joint inflammation.

    OpenAIRE

    van de Loo, A. A.; van den Berg, W B

    1990-01-01

    Murine recombinant interleukin 1 was injected intra-articularly into mice. It induced a clear effect on patellar cartilage within 24 hours. A low dose of interleukin 1 (1 ng) elicited a significant reduction in [35S]sulphate incorporation (50%) into proteoglycans and an accelerated breakdown (twofold) of 35S prelabelled proteoglycan. Proteoglycan breakdown returned to normal rates (approximately 10%/day) 48 hours after a single interleukin 1 injection. Recovery of proteoglycan synthesis was d...

  17. Spectrocolorimetric evaluation of repaired articular cartilage after a microfracture

    Directory of Open Access Journals (Sweden)

    Dohi Yoshihiro

    2008-09-01

    Full Text Available Abstract Background In clinical practice, surgeons differentiate color changes in repaired cartilage compared with surrounding intact cartilage, but cannot quantify these color changes. Objective assessments are required. A spectrocolorimeter was used to evaluate whether intact and repaired cartilage can be quantified. Findings We investigated the use of a spectrocolorimeter and the application of two color models (L* a* b* colorimetric system and spectral reflectance distribution to describe and quantify articular cartilage. In this study, we measured the colors of intact and repaired cartilage after a microfracture. Histologically, the repaired cartilage was a mixture of fibrocartilage and hyaline cartilage. In the L* a* b* colorimetric system, the L* and a* values recovered to close to the values of intact cartilage, whereas the b* value decreased over time after the operation. Regarding the spectral reflectance distribution at 12 weeks after the operation, the repaired cartilage had a higher spectral reflectance ratio than intact cartilage between wavelengths of 400 to 470 nm. Conclusion This study reports the first results regarding the relationship between spectrocolorimetric evaluation and the histological findings of repair cartilage after a microfracture. Our findings demonstrate the ability of spectrocolorimetric measurement to judge the repair cartilage after treatment on the basis of objective data such as the L*, a* and b* values and the SRP as a coincidence index of the spectral reflectance curve.

  18. Handheld-Level Electromechanical Cartilage Reshaping Device.

    Science.gov (United States)

    Kim, Sehwan; Manuel, Cyrus T; Wong, Brian J F; Chung, Phil-Sang; Mo, Ji-Hun

    2015-06-01

    We have developed a handheld-level multichannel electromechanical reshaping (EMR) cartilage device and evaluated the feasibility of providing a means of cartilage reshaping in a clinical outpatient setting. The effect of EMR on pig costal cartilage was evaluated in terms of shape change, tissue heat generation, and cell viability. The pig costal cartilage specimens (23 mm × 6.0 mm × 0.7 mm) were mechanically deformed to 90 degrees and fixed to a plastic jig and applied 5, 6, 7, and 8 V up to 8 minutes to find the optimal dosimetry for the our developed EMR device. The results reveal that bend angle increased with increasing voltage and application time. The maximum bend angle obtained was 70.5 ± 7.3 at 8 V, 5 minutes. The temperature of flat pig costal cartilage specimens were measured, while a constant electric voltage was applied to three pairs of electrodes that were inserted into the cartilages. The nonthermal feature of EMR was validated by a thermal infrared camera; that is, the maximum temperate of the flat cartilages is 20.3°C at 8 V. Cell viability assay showed no significant difference in cell damaged area from 3 to 7 minutes exposure with 7 V. In conclusion, the multichannel EMR device that was developed showed a good feasibility of cartilage shaping with minimal temperature change. PMID:26126226

  19. Lubricin reduces cartilage--cartilage integration.

    Science.gov (United States)

    Schaefer, Dirk B; Wendt, David; Moretti, Matteo; Jakob, Marcel; Jay, Gregory D; Heberer, Michael; Martin, Ivan

    2004-01-01

    Cartilage integration in vivo does not occur, such that even cartilage fissures do not heal. This could be due not only to the limited access of chondrocytes to the wound, but also to exogenous factors. In this paper, we tested the hypothesis that lubricin, a lubricating protein physiologically present in the synovial fluid, reduces the integrative cartilage repair capacity. Disk/ring composites of bovine articular cartilage were prepared using concentric circular blades and cultured for 6 weeks with or without treatment with 250 microg/ml lubricin applied three times per week. Following culture, the percentage of contact area between the disks and the rings, as assessed by light microscopy, were equal in both groups. The adhesive strength of the integration interface, as assessed by push-out mechanical tests, was markedly and significantly lower in lubricin-treated specimens (2.5 kPa) than in the controls (28.7 kPa). Histological observation of Safranin-O stained cross-sections confirmed the reduced integration in the lubricin treated composites. Our findings suggest that the synovial milieu, by providing lubrication of cartilage surfaces, impairs cartilage--cartilage integration. PMID:15299281

  20. Formative Measurement and Academic Research: In Search of Measurement Theory

    Science.gov (United States)

    Hardin, Andrew M.; Chang, Jerry Cha-Jan; Fuller, Mark A.; Torkzadeh, Gholamreza

    2011-01-01

    The use of causal indicators to formatively measure latent constructs appears to be on the rise, despite what appears to be a troubling lack of consistency in their application. Scholars in any discipline are responsible not only for advancing theoretical knowledge in their domain of study but also for addressing methodological issues that…

  1. Cartilage Repair Surgery: Outcome Evaluation by Using Noninvasive Cartilage Biomarkers Based on Quantitative MRI Techniques?

    Directory of Open Access Journals (Sweden)

    Pia M. Jungmann

    2014-01-01

    Full Text Available Background. New quantitative magnetic resonance imaging (MRI techniques are increasingly applied as outcome measures after cartilage repair. Objective. To review the current literature on the use of quantitative MRI biomarkers for evaluation of cartilage repair at the knee and ankle. Methods. Using PubMed literature research, studies on biochemical, quantitative MR imaging of cartilage repair were identified and reviewed. Results. Quantitative MR biomarkers detect early degeneration of articular cartilage, mainly represented by an increasing water content, collagen disruption, and proteoglycan loss. Recently, feasibility of biochemical MR imaging of cartilage repair tissue and surrounding cartilage was demonstrated. Ultrastructural properties of the tissue after different repair procedures resulted in differences in imaging characteristics. T2 mapping, T1rho mapping, delayed gadolinium-enhanced MRI of cartilage (dGEMRIC, and diffusion weighted imaging (DWI are applicable on most clinical 1.5 T and 3 T MR scanners. Currently, a standard of reference is difficult to define and knowledge is limited concerning correlation of clinical and MR findings. The lack of histological correlations complicates the identification of the exact tissue composition. Conclusions. A multimodal approach combining several quantitative MRI techniques in addition to morphological and clinical evaluation might be promising. Further investigations are required to demonstrate the potential for outcome evaluation after cartilage repair.

  2. Secondary cartilage revealed in a non-avian dinosaur embryo.

    Directory of Open Access Journals (Sweden)

    Alida M Bailleul

    Full Text Available The skull and jaws of extant birds possess secondary cartilage, a tissue that arises after bone formation during embryonic development at articulations, ligamentous and muscular insertions. Using histological analysis, we discovered secondary cartilage in a non-avian dinosaur embryo, Hypacrosaurus stebingeri (Ornithischia, Lambeosaurinae. This finding extends our previous report of secondary cartilage in post-hatching specimens of the same dinosaur species. It provides the first information on the ontogeny of avian and dinosaurian secondary cartilages, and further stresses their developmental similarities. Secondary cartilage was found in an embryonic dentary within a tooth socket where it is hypothesized to have arisen due to mechanical stresses generated during tooth formation. Two patterns were discerned: secondary cartilage is more restricted in location in this Hypacrosaurus embryo, than it is in Hypacrosaurus post-hatchlings; secondary cartilage occurs at far more sites in bird embryos and nestlings than in Hypacrosaurus. This suggests an increase in the number of sites of secondary cartilage during the evolution of birds. We hypothesize that secondary cartilage provided advantages in the fine manipulation of food and was selected over other types of tissues/articulations during the evolution of the highly specialized avian beak from the jaws of their dinosaurian ancestors.

  3. Secondary cartilage revealed in a non-avian dinosaur embryo.

    Science.gov (United States)

    Bailleul, Alida M; Hall, Brian K; Horner, John R

    2013-01-01

    The skull and jaws of extant birds possess secondary cartilage, a tissue that arises after bone formation during embryonic development at articulations, ligamentous and muscular insertions. Using histological analysis, we discovered secondary cartilage in a non-avian dinosaur embryo, Hypacrosaurus stebingeri (Ornithischia, Lambeosaurinae). This finding extends our previous report of secondary cartilage in post-hatching specimens of the same dinosaur species. It provides the first information on the ontogeny of avian and dinosaurian secondary cartilages, and further stresses their developmental similarities. Secondary cartilage was found in an embryonic dentary within a tooth socket where it is hypothesized to have arisen due to mechanical stresses generated during tooth formation. Two patterns were discerned: secondary cartilage is more restricted in location in this Hypacrosaurus embryo, than it is in Hypacrosaurus post-hatchlings; secondary cartilage occurs at far more sites in bird embryos and nestlings than in Hypacrosaurus. This suggests an increase in the number of sites of secondary cartilage during the evolution of birds. We hypothesize that secondary cartilage provided advantages in the fine manipulation of food and was selected over other types of tissues/articulations during the evolution of the highly specialized avian beak from the jaws of their dinosaurian ancestors. PMID:23418610

  4. Cartilage Engineering and Microgravity

    Science.gov (United States)

    Toffanin, R.; Bader, A.; Cogoli, A.; Carda, C.; Fantazzini, P.; Garrido, L.; Gomez, S.; Hall, L.; Martin, I.; Murano, E.; Poncelet, D.; Pörtner, R.; Hoffmann, F.; Roekaerts, D.; Ronney, P.; Triebel, W.; Tummers, M.

    2005-06-01

    The complex effects of mechanical forces and growth factors on articular cartilage development still need to be investigated in order to identify optimal conditions for articular cartilage repair. Strictly controlled in vitro studies under modelled or space microgravity conditions can improve our understanding of the fundamental role of gravity in articular cartilage development. The main objective of this Topical Team is to use modelled microgravity as a tool to elucidate the fundamental science of cartilage regeneration. Particular attention is, therefore, given to the effects of physical forces under altered gravitational conditions, applied using controlled bioreactor systems, on cell metabolism, cell differentiation and tissue development. Specific attention is also directed toward the potential advantages of using magnetic resonance methods for the non-destructive characterisation of scaffolds, chondrocytes-polymer constructs and tissue engineered cartilage.

  5. Development of artificial articular cartilage.

    Science.gov (United States)

    Oka, M; Ushio, K; Kumar, P; Ikeuchi, K; Hyon, S H; Nakamura, T; Fujita, H

    2000-01-01

    Attempts have been made to develop an artificial articular cartilage on the basis of a new viewpoint of joint biomechanics in which the lubrication and load-bearing mechanisms of natural and artificial joints are compared. Polyvinyl alcohol hydrogel (PVA-H), 'a rubber-like gel', was investigated as an artificial articular cartilage and the mechanical properties of this gel were improved through a new synthetic process. In this article the biocompatibility and various mechanical properties of the new improved PVA-H is reported from the perspective of its usefulness as an artificial articular cartilage. As regards lubrication, the changes in thickness and fluid pressure of the gap formed between a glass plate and the specimen under loading were measured and it was found that PVA-H had a thicker fluid film under higher pressures than polyethylene (PE) did. The momentary stress transmitted through the specimen revealed that PVA-H had a lower peak stress and a longer duration of sustained stress than PE, suggesting a better damping effect. The wear factor of PVA-H was approximately five times that of PE. Histological studies of the articular cartilage and synovial membranes around PVA-H implanted for 8-52 weeks showed neither inflammation nor degenerative changes. The artificial articular cartilage made from PVA-H could be attached to the underlying bone using a composite osteochondral device made from titanium fibre mesh. In the second phase of this work, the damage to the tibial articular surface after replacement of the femoral surface in dogs was studied. Pairs of implants made of alumina, titanium or PVA-H on titanium fibre mesh were inserted into the femoral condyles. The two hard materials caused marked pathological changes in the articular cartilage and menisci, but the hydrogel composite replacement caused minimal damage. The composite osteochondral device became rapidly attached to host bone by ingrowth into the supporting mesh. The clinical implications of

  6. Ultrasound Backscattering Is Anisotropic in Bovine Articular Cartilage.

    Science.gov (United States)

    Inkinen, Satu I; Liukkonen, Jukka; Tiitu, Virpi; Virén, Tuomas; Jurvelin, Jukka S; Töyräs, Juha

    2015-07-01

    Collagen, proteoglycans and chondrocytes can contribute to ultrasound scattering in articular cartilage. However, anisotropy of ultrasound scattering in cartilage is not fully characterized. We investigate this using a clinical intravascular ultrasound device with ultrasound frequencies of 9 and 40 MHz. Osteochondral samples were obtained from intact bovine patellas, and cartilage was imaged in two perpendicular directions: through articular and lateral surfaces. At both frequencies, ultrasound backscattering was higher (p < 0.05) when measured through the lateral surface of cartilage. In addition, the composition and structure of articular cartilage were investigated with multiple reference methods involving light microscopy, digital densitometry, polarized light microscopy and Fourier infrared imaging. Reference methods indicated that acoustic anisotropy of ultrasound scattering arises mainly from non-uniform distribution of chondrocytes and anisotropic orientation of collagen fibers. To conclude, ultrasound backscattering in articular cartilage was found to be anisotropic and dependent on the frequency in use. PMID:25933711

  7. Characterization of the collagen component of cartilage repair tissue of the talus with quantitative MRI: comparison of T2 relaxation time measurements with a diffusion-weighted double-echo steady-state sequence (dwDESS)

    Energy Technology Data Exchange (ETDEWEB)

    Kretzschmar, M.; Hainc, N.; Studler, U. [University Hospital Basel, Department of Radiology, Basel (Switzerland); Bieri, O. [University Hospital Basel, Division of Radiological Physics, Basel (Switzerland); Miska, M. [University Hospital, Department of Orthopedics, Heidelberg (Germany); Wiewiorski, M.; Valderrabano, V. [University Hospital Basel, Department of Orthopedic Surgery, Basel (Switzerland)

    2015-04-01

    The purpose of this study was to characterize the collagen component of repair tissue (RT) of the talus after autologous matrix-induced chondrogenesis (AMIC) using quantitative T2 and diffusion-weighted imaging. Mean T2 values and diffusion coefficients of AMIC-RT and normal cartilage of the talus of 25 patients with posttraumatic osteochondral lesions and AMIC repair were compared in a cross-sectional design using partially spoiled steady-state free precession (pSSFP) for T2 quantification, and diffusion-weighted double-echo steady-state (dwDESS) for diffusion measurement. RT and cartilage were graded with modified Noyes and MOCART scores on morphological sequences. An association between follow-up interval and quantitative MRI measures was assessed using multivariate regression, after stratifying the cohort according to time interval between surgery and MRI. Mean T2 of the AMIC-RT and cartilage were 43.1 ms and 39.1 ms, respectively (p = 0.26). Mean diffusivity of the RT (1.76 μm{sup 2}/ms) was significantly higher compared to normal cartilage (1.46 μm{sup 2}/ms) (p = 0.0092). No correlation was found between morphological and quantitative parameters. RT diffusivity was lowest in the subgroup with follow-up >28 months (p = 0.027). Compared to T2-mapping, dwDESS demonstrated greater sensitivity in detecting differences in the collagen matrix between AMIC-RT and cartilage. Decreased diffusivity in patients with longer follow-up times may indicate an increased matrix organization of RT. (orig.)

  8. Preliminary investigation of intrinsic UV fluorescence spectroscopic changes associated with proteolytic digestion of bovine articular cartilage

    Science.gov (United States)

    Lewis, William; Padilla-Martinez, Juan-Pablo; Ortega-Martinez, Antonio; Franco, Walfre

    2016-03-01

    Degradation and destruction of articular cartilage is the etiology of osteoarthritis (OA), an entity second only to cardiovascular disease as a cause of disability in the United States. Joint mechanics and cartilage biochemistry are believed to play a role in OA; an optical tool to detect structural and chemical changes in articular cartilage might offer benefit for its early detection and treatment. The objective of the present study was to identify the spectral changes in intrinsic ultraviolet (UV) fluorescence of cartilage that occur after proteolytic digestion of cartilage. Bovine articular cartilage samples were incubated in varying concentrations of collagenase ranging from 10ug/mL up to 5mg/mL for 18 hours at 37°C, a model of OA. Pre- and post-incubation measurements were taken of the UV excitation-emission spectrum of each cartilage sample. Mechanical tests were performed to determine the pre- and post-digestion force/displacement ratio associated with indentation of each sample. Spectral changes in intrinsic cartilage fluorescence and stiffness of the cartilage were associated with proteolytic digestion. In particular, changes in the relative intensity of fluorescence peaks associated with pentosidine crosslinks (330 nm excitation, 390 nm emission) and tryptophan (290 nm excitation, 340 nm emission) were found to correlate with different degrees of cartilage digestion and cartilage stiffness. In principle, it may be possible to use UV fluorescence spectral data for early detection of damage to articular cartilage, and as a surrogate measure for cartilage stiffness.

  9. Viscoelastic properties of bovine articular cartilage attached to subchondral bone at high frequencies

    Directory of Open Access Journals (Sweden)

    Shepherd Duncan ET

    2009-06-01

    Full Text Available Abstract Background Articular cartilage is a viscoelastic material, but its exact behaviour under the full range of physiological loading frequencies is unknown. The objective of this study was to measure the viscoelastic properties of bovine articular cartilage at loading frequencies of up to 92 Hz. Methods Intact tibial plateau cartilage, attached to subchondral bone, was investigated by dynamic mechanical analysis (DMA. A sinusoidally varying compressive force of between 16 N and 36 N, at frequencies from 1 Hz to 92 Hz, was applied to the cartilage surface by a flat indenter. The storage modulus, loss modulus and phase angle (between the applied force and the deformation induced were determined. Results The storage modulus, E', increased with increasing frequency, but at higher frequencies it tended towards a constant value. Its dependence on frequency, f, could be represented by, E' = Aloge (f + B where A = 2.5 ± 0.6 MPa and B = 50.1 ± 12.5 MPa (mean ± standard error. The values of the loss modulus (4.8 ± 1.0 MPa mean ± standard deviation were much less than the values of storage modulus and showed no dependence on frequency. The phase angle was found to be non-zero for all frequencies tested (4.9 ± 0.6°. Conclusion Articular cartilage is viscoelastic throughout the full range of frequencies investigated. The behaviour has implications for mechanical damage to articular cartilage and the onset of osteoarthritis. Storage modulus increases with frequency, until the plateau region is reached, and has a higher value than loss modulus. Furthermore, loss modulus does not increase with loading frequency. This means that more energy is stored by the tissue than is dissipated and that this effect is greater at higher frequencies. The main mechanism for this excess energy to be dissipated is by the formation of cracks.

  10. Evaluation of influence of proteoglycans on hydration of articular cartilage with the use of ultrasound

    Directory of Open Access Journals (Sweden)

    Yi-yi YANG

    2015-04-01

    Full Text Available Objective To monitor the changes in hydration behaviour of articular cartilage induced by degradation of proteoglycans, and to explore the effect of proteoglycans on hydration behaviour of articular cartilage by using high-frequency ultrasound. Methods Twelve porcine patellae with smooth cartilage surface were prepared and equally divided into two groups: normal group without any enzyme treatment, and trypsin group they were treated with 0.25% trypsin for 8h to digest proteoglycan in the cartilage. The hydration behaviour of the cartilage tissue was scanned by high-frequency ultrasound system with a central frequency of 25MHz. Parameters including cartilage hydration strain and cartilage thickness were measured. The histopathological changes in the articular cartilage were observed under a light microscope. Results It took approximately 20min to reach equilibrium during the hydration process in the normal cartilages, while proteoglycan-degraded cartilage took only about 5min to achieve equilibrium. The equilibrium strain of normal cartilage was 3.5%±0.5%. The degradation of proteoglycans induced a significant decrease in equilibrium strain (1.8%±0.2%, P0.05. Conclusion Proteoglycans play an important role in hydration behaviour of articular cartilage. The degradation of proteoglycans could induce degeneration of cartilage structure and decrease in hydration behaviour after dehydration. DOI: 10.11855/j.issn.0577-7402.2015.03.03

  11. Anti-cartilage antibody.

    Science.gov (United States)

    Greenbury, C L; Skingle, J

    1979-08-01

    Antibody to cartilage has been demonstrated by indirect immunofluorescence on rat trachea in the serum of about 3% of 1126 patients with rheumatoid arthritis. Titres ranged from 1:20 to 1:640. The antibody was not found in 284 patients with primary or secondary osteoarthritis or in 1825 blood donors, nor, with the exception of two weak reactors, in 1314 paraplegic patients. In most cases the antibody appears to be specific for native type II collagen. Using this as an antigen in a haemagglutination test 94% of anti-cartilage sera were positive, whereas among 100 rheumatoid control sera there were only three weak positives. More than 80% of patients with antibody had some erosion of articular cartilage, but there was no correlation with age, sex, duration of disease, nor any recognisable clinical event or change.

  12. Degeneration of osteoarthritis cartilage

    DEFF Research Database (Denmark)

    Jørgensen, Dan Richter

    Osteoarthritis (OA) is a widespread, chronic joint disease for which there are currently no effective treatments beyond symptom relief. The lack of any approved disease modifying osteoarthritic drugs may partly be explained by insufficient disease understanding, but may also be tied to the absence...... spatial cartilage changes that were observed in our study and in recent literature. The cartilage “Activity” marker is shown to have a state-of-the-art performance in separating healthy knees from OA knees and is also shown to predict knee replacement which is a clinically relevant endpoint for OA....

  13. Tibiofemoral cartilage contact biomechanics in patients after reconstruction of a ruptured anterior cruciate ligament.

    Science.gov (United States)

    Hosseini, Ali; Van de Velde, Samuel; Gill, Thomas J; Li, Guoan

    2012-11-01

    We investigated the in vivo cartilage contact biomechanics of the tibiofemoral joint in patients after reconstruction of a ruptured anterior cruciate ligament (ACL). A dual fluoroscopic and MR imaging technique was used to investigate the cartilage contact biomechanics of the tibiofemoral joint during in vivo weight-bearing flexion of the knee in eight patients 6 months following clinically successful reconstruction of an acute isolated ACL rupture. The location of tibiofemoral cartilage contact, size of the contact area, cartilage thickness at the contact area, and magnitude of the cartilage contact deformation of the ACL-reconstructed knees were compared with those previously measured in intact (contralateral) knees and ACL-deficient knees of the same subjects. Contact biomechanics of the tibiofemoral cartilage after ACL reconstruction were similar to those measured in intact knees. However, at lower flexion, the abnormal posterior and lateral shift of cartilage contact location to smaller regions of thinner tibial cartilage that has been described in ACL-deficient knees persisted in ACL-reconstructed knees, resulting in an increase of the magnitude of cartilage contact deformation at those flexion angles. Reconstruction of the ACL restored some of the in vivo cartilage contact biomechanics of the tibiofemoral joint to normal. Clinically, recovering anterior knee stability might be insufficient to prevent post-operative cartilage degeneration due to lack of restoration of in vivo cartilage contact biomechanics. PMID:22528687

  14. Costal Cartilage Grafts in Rhinoplasty.

    Science.gov (United States)

    Fedok, Fred G

    2016-01-01

    Cartilage grafts are regularly used in rhinoplasty. Septal and auricular donor sites are commonly used. Many situations compel the surgeon to use other alternative donor sites, including revision rhinoplasty and trauma. Many patients have a small amount of native septal cartilage and are unable to provide adequate septal cartilage to be used for frequently performed rhinoplasty maneuvers. The rib cage provides an enormous reserve of costal cartilage that can be carved into a variety of necessary grafts. A description of the technique of harvesting costal cartilage, a review of complications and management, and illustrative cases examples are included. PMID:26616708

  15. MORPHOMETRIC STUDY OF THYROID CARTILAGES IN WESTERN INDIA

    Directory of Open Access Journals (Sweden)

    Mohini M.Joshi

    2015-06-01

    Full Text Available Background: Morphometrical evaluation of the larynx has always been interesting for both morphologists and the physicians. A good understanding of the anatomy and the knowledge of variations in the laryngeal cartilages is important Objective: Objective of the present study was to collect exact and reliable morphometric data of thyroid cartilage in adult human larynx of regional population. Methods: The totals of 50 thyroid cartilage specimens were studied. The cartilages were preserved in 5% formalin. The measurements were taken with the help of Digital Vernier Caliper. The cartilages were weighed on Single pan electronic balance. For each of the parameters, the mean, standard deviation (S.D. and range was calculated. Results: Mean depth of superior thyroid notch was 9.7± 3.36 mm. Asymmetry between the length of superior horn of thyroid cartilages in left and right sides can be seen, but difference was not statistically significant (p>0.05. It is observed that inner thyroid angle varies from 55 to 1040 and outer thyroid angle varies from 53 to 990. In present study mean weight of thyroid cartilage was 6.70±1.55 grams. Conclusions: A fair amount of intersubject variability in the dimensions was observed. Bilateral asymmetry, though present in majority of specimens, was insignificant. Various dimensions of thyroid cartilages are smaller as compared to the western population.

  16. A Novel Approach to Stimulate Cartilage Repair: Targeting Collagen Turnover

    OpenAIRE

    Bastiaansen-Jenniskens, Yvonne Maria

    2009-01-01

    textabstractOA is a complex disease of which the ethiopathology is not completely known and therapies to repair cartilage are still under investigation. The increase of collagen type II expression in osteoarthritic cartilage suggests an activated repair mechanism that is however ineffective in repairing or maintaining the ECM homeostasis. We therefore investigated the ability to modulate the formation of a functional collagen type II network that can ultimately contribute to innovation of car...

  17. Use of magnetic forces to promote stem cell aggregation during differentiation, and cartilage tissue modeling.

    Science.gov (United States)

    Fayol, D; Frasca, G; Le Visage, C; Gazeau, F; Luciani, N; Wilhelm, C

    2013-05-14

    Magnetic forces induce cell condensation necessary for stem cell differentiation into cartilage and elicit the formation of a tissue-like structure: Magnetically driven fusion of aggregates assembled by micromagnets results in the formation of a continuous tissue layer containing abundant cartilage matrix. PMID:23526452

  18. Cartilage repair: Generations of autologous chondrocyte transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Marlovits, Stefan [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)]. E-mail: stefan.marlovits@meduniwien.ac.at; Zeller, Philip [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Singer, Philipp [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Resinger, Christoph [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Vecsei, Vilmos [Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

    2006-01-15

    Articular cartilage in adults has a limited capacity for self-repair after a substantial injury. Surgical therapeutic efforts to treat cartilage defects have focused on delivering new cells capable of chondrogenesis into the lesions. Autologous chondrocyte transplantation (ACT) is an advanced cell-based orthobiologic technology used for the treatment of chondral defects of the knee that has been in clinical use since 1987 and has been performed on 12,000 patients internationally. With ACT, good to excellent clinical results are seen in isolated post-traumatic lesions of the knee joint in the younger patient, with the formation of hyaline or hyaline-like repair tissue. In the classic ACT technique, chondrocytes are isolated from small slices of cartilage harvested arthroscopically from a minor weight-bearing area of the injured knee. The extracellular matrix is removed by enzymatic digestion, and the cells are then expanded in monolayer culture. Once a sufficient number of cells has been obtained, the chondrocytes are implanted into the cartilage defect, using a periosteal patch over the defect as a method of cell containment. The major complications are periosteal hypertrophy, delamination of the transplant, arthrofibrosis and transplant failure. Further improvements in tissue engineering have contributed to the next generation of ACT techniques, where cells are combined with resorbable biomaterials, as in matrix-associated autologous chondrocyte transplantation (MACT). These biomaterials secure the cells in the defect area and enhance their proliferation and differentiation.

  19. The Frictional Coefficient of Bovine Knee Articular Cartilage

    Institute of Scientific and Technical Information of China (English)

    Qian Shan-hua; Ge Shi-rong; Wang Qing-liang

    2006-01-01

    The normal displacement of articular cartilage was measured under load and in sliding, and the coefficient of friction during sliding was measured using a UMT-2 Multi-Specimen Test System. The maximum normal displacement under load and the start-up frictional coefficient have similar tendency of variation with loading time. The sliding speed does not significantly influence the frictional coefficient of articular cartilage.

  20. Articular cartilage stem cell signalling

    OpenAIRE

    Karlsson, Camilla; Lindahl, Anders

    2009-01-01

    The view of articular cartilage as a non-regeneration organ has been challenged in recent years. The articular cartilage consists of distinct zones with different cellular and molecular phenotypes, and the superficial zone has been hypothesized to harbour stem cells. Furthermore, the articular cartilage demonstrates a distinct pattern regarding stem cell markers (that is, Notch-1, Stro-1, and vascular cell adhesion molecule-1). These results, in combination with the positive identification of...

  1. Transcriptomic profiling of cartilage ageing

    OpenAIRE

    Mandy Jayne Peffers; Xuan Liu; Peter David Clegg

    2014-01-01

    The musculoskeletal system is severely affected by the ageing process, with many tissues undergoing changes that lead to loss of function and frailty. Articular cartilage is susceptible to age related diseases, such as osteoarthritis. Applying RNA-Seq to young and old equine cartilage, we identified an over-representation of genes with reduced expression relating to extracellular matrix, degradative proteases, matrix synthetic enzymes, cytokines and growth factors in cartilage from older dono...

  2. Study on the Microstructure of Human Articular Cartilage/Bone Interface

    Institute of Scientific and Technical Information of China (English)

    Yaxiong Liu; Qin Lian; Jiankang He; Jinna Zhao; Zhongmin Jin; Dichen Li

    2011-01-01

    For improving the theory of gradient microstructure of cartilage/bone interface, human distal femurs were studied. Scanning Electron Microscope (SEM), histological sections and MicroCT were used to observe, measure and model the microstructure of cartilage/bone interface. The results showed that the cartilage/bone interface is in a hierarchical structure which is composed of four different tissue layers. The interlocking of hyaline cartilage and calcified cartilage and that of calcified cartilage and subchondral bone are in the manner of"protrusion-pore" with average diameter of 17.0 μm and 34.1 μm respectively. In addition, the cancellous bone under the cartilage is also formed by four layer hierarchical structure, and the adjacent layers are connected by bone trabecula in the shape of H, I and Y, forming a complex interwoven network structure. Finally, the simplified structure model of the cartilage/bone interface was proposed according to the natural articular cartilage/bone interface. The simplified model is a 4-layer gradient biomimetic structure, which corresponds to four different tissues of natural cartilage/bone interface. The results of this work would be beneficial to the design of bionic scaffold for the tissue engineering of articular cartilage/bone.

  3. Construction of tissue-engineered cartilage using human placenta-derived stem cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Human placenta-derived stem cells (hPDSCs) were isolated by trypsinization and further induced into cartilage cells in vitro.The engineered cartilage was constructed by combining hPDSCs with collagen sponge and the cartilage formation was observed by implantation into nude mice.Results showed that hPDSCs featured mesenchymal stem cells and maintained proliferation in vitro for over 30 passages while remaining undifferentiated.All results indicated that hPDSCs have the potential to differentiate into functional cartilage cells in vitro when combined with collagen sponge,which provided experimental evidence for prospective clinical application.

  4. Site-1 protease is required for cartilage development in zebrafish.

    Science.gov (United States)

    Schlombs, Kornelia; Wagner, Thomas; Scheel, Jochen

    2003-11-25

    gonzo (goz) is a zebrafish mutant with defects in cartilage formation. The goz phenotype comprises cartilage matrix defects and irregular chondrocyte morphology. Expression of endoderm, mesoderm, and cartilage marker genes is, however, normal, indicating a defect in chondrocyte morphogenesis. The mutated gene responsible for the goz phenotype, identified by positional cloning and confirmed by phosphomorpholino knockdown, encodes zebrafish site-1 protease (s1p). S1P has been shown to process and activate sterol regulatory element-binding proteins (SREBPs), which regulate expression of key enzymes of lipid biosynthesis or transport. This finding is consistent with the abnormal distribution of lipids in goz embryos. Knockdown of site-2 protease, which is also involved in activation of SREBPs, results in similar lipid and cartilage phenotypes as S1P knockdown. However, knockdown of SREBP cleavage-activating protein, which forms a complex with SREBP and is essential for S1P cleavage, results only in lipid phenotypes, whereas cartilage appears normal. This indicates that the cartilage phenoptypes of goz are caused independently of the lipid defects. PMID:14612568

  5. Nanomechanical phenotype of chondroadherin-null murine articular cartilage.

    Science.gov (United States)

    Batista, Michael A; Nia, Hadi T; Önnerfjord, Patrik; Cox, Karen A; Ortiz, Christine; Grodzinsky, Alan J; Heinegård, Dick; Han, Lin

    2014-09-01

    Chondroadherin (CHAD), a class IV small leucine rich proteoglycan/protein (SLRP), was hypothesized to play important roles in regulating chondrocyte signaling and cartilage homeostasis. However, its roles in cartilage development and function are not well understood, and no major osteoarthritis-like phenotype was found in the murine model with CHAD genetically deleted (CHAD(-/-)). In this study, we used atomic force microscopy (AFM)-based nanoindentation to quantify the effects of CHAD deletion on changes in the biomechanical function of murine cartilage. In comparison to wild-type (WT) mice, CHAD-deletion resulted in a significant ≈70-80% reduction in the indentation modulus, Eind, of the superficial zone knee cartilage of 11 weeks, 4 months and 1 year old animals. This mechanical phenotype correlates well with observed increases in the heterogeneity collagen fibril diameters in the surface zone. The results suggest that CHAD mainly plays a major role in regulating the formation of the collagen fibrillar network during the early skeletal development. In contrast, CHAD-deletion had no appreciable effects on the indentation mechanics of middle/deep zone cartilage, likely due to the dominating role of aggrecan in the middle/deep zone. The presence of significant rate dependence of the indentation stiffness in both WT and CHAD(-/-) knee cartilage suggested the importance of both fluid flow induced poroelasticity and intrinsic viscoelasticity in murine cartilage biomechanical properties. Furthermore, the marked differences in the nanomechanical behavior of WT versus CHAD(-/-) cartilage contrasted sharply with the relative absence of overt differences in histological appearance. These observations highlight the sensitivity of nanomechanical tools in evaluating structural and mechanical phenotypes in transgenic mice. PMID:24892719

  6. Mechanical testing of hydrogels in cartilage tissue engineering: beyond the compressive modulus.

    Science.gov (United States)

    Xiao, Yinghua; Friis, Elizabeth A; Gehrke, Stevin H; Detamore, Michael S

    2013-10-01

    Injuries to articular cartilage result in significant pain to patients and high medical costs. Unfortunately, cartilage repair strategies have been notoriously unreliable and/or complex. Biomaterial-based tissue-engineering strategies offer great promise, including the use of hydrogels to regenerate articular cartilage. Mechanical integrity is arguably the most important functional outcome of engineered cartilage, although mechanical testing of hydrogel-based constructs to date has focused primarily on deformation rather than failure properties. In addition to deformation testing, as the field of cartilage tissue engineering matures, this community will benefit from the addition of mechanical failure testing to outcome analyses, given the crucial clinical importance of the success of engineered constructs. However, there is a tremendous disparity in the methods used to evaluate mechanical failure of hydrogels and articular cartilage. In an effort to bridge the gap in mechanical testing methods of articular cartilage and hydrogels in cartilage regeneration, this review classifies the different toughness measurements for each. The urgency for identifying the common ground between these two disparate fields is high, as mechanical failure is ready to stand alongside stiffness as a functional design requirement. In comparing toughness measurement methods between hydrogels and cartilage, we recommend that the best option for evaluating mechanical failure of hydrogel-based constructs for cartilage tissue engineering may be tensile testing based on the single edge notch test, in part because specimen preparation is more straightforward and a related American Society for Testing and Materials (ASTM) standard can be adopted in a fracture mechanics context.

  7. Low level laser intensity improves propulsive appliance effects on condylar cartilage

    Science.gov (United States)

    Figueiredo, Augusto C. R.; dos Santos, Fernanda C. A.; Capeletti, Lucas R.; Galdino, Marcos V. B.; Araújo, Renan V.; Marques, Mara R.

    2012-01-01

    Mandibular propulsive appliance (MPA) stimulates cell proliferation and gene expression on mandible condylar cartilage (Marques et al., 2008). However, its association with low level laser therapy (LLLT) is unknown. This study evaluated the effects of LLLT associated to MPA on mandibular condyle. Twenty Wistar rats were divided into four groups. Group I received any treatment. Group II was bilaterally irradiated on temporomandibular joint with 10 J/cm2 low level laser (780nm, 40mW and 10s) on alternate days. Group III used the propulsive appliance for ten hours daily and Group IV used the appliance daily and was irradiated on alternate days. After 15 days the animals were killed by lethal doses of anesthetics. The condyles were fixed in Methacarn solution and decalcified in 4.13% EDTA solution for 30 days. Seriate saggital 5 μm-thick sections were stained by the hematoxilin-eosin method. Morphological and morphometric analyses were performed to measure the length and the height of the mandibular condyle, the thickness of the condilar cartilage and the bone mass. Results were expressed as mean +/- standard deviation (one-way ANOVA, Tukey's post-test.) The appliance increased all measures compared to the control group, except bone mass. Alone, LLLT had no effects on all measures, however, the association of the appliance with the LLLT increased condylar cartilage and bone mass significantly compared to the others groups. These results suggest that LLLT improves the effects of mandibular propulsive appliance in the condylar cartilage growth and formation of bone mass.

  8. A STUDY ON STRUCTURE AND THICKNESS OF ISTHMUS OF CARTILAG E OF PINNA

    Directory of Open Access Journals (Sweden)

    Satyanarayana

    2015-05-01

    Full Text Available INTRODUCTION: A variety of organic and inorganic materials is used as grafts in Ossiculoplasty and reconstruction of the outer attic wall and posterior wall of External Auditory Meatus. Tragal cartilage, Conchal cartilage and septal cartilages are frequently used as auto grafts during Tympanoplasty surgery for reconstruction of Ossicular chain. Cartilage grafts used for Ossicular replacement should be thick, sturdy, easily sculpted and without much elasticity. If the graft has elastic nature it tends to reduce the conduction of sound vibrations. Auricular cartilage is accessible through the same post aural incision used for the mastoid surgery. If the auricular cartilage is palpated for the thickness, one would find that the thickest part is the isthmus. It is felt below and posterior to the inter tragal sulcus. The present study is to measure the thickness of the isthmus part of the auricle cartilage. It also includes study of histology of the cartilage of isthmus to observe the stacks of cells present between the two layers of the perichondrium. MATERIALS AND METHODS: The cartilage of isthmus from 36 cadavers is dissected to measure its thickness and for histology study. Cartilage of isthmus from 36 patients undergoing Modified Radical Mastoidectomy is measured for their thickness and histology is studied. A sterile steel calipers is used to measure the thickness of the cartilage, after exposing the cartilage from posterior aspect during surgery. The tips of the calipers are kept touching the perichondrium on both sides. Thin histology sections are taken after embedding the cartilage in paraffin moulds. Hematoxyline and Eosin stain is used to study the histology. The thickest portion of the cartilage is sculpted to be used as a strut in Type III Tympanoplasty. OBSERVATIONS: The thickness of the cartilage varied from 2.1 to 3mm. The number of stacks of chondrocytes varied from 5 to 7. The physical nature of the cartilage is sturdy and easily

  9. T2 star relaxation times for assessment of articular cartilage at 3 T: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Mamisch, Tallal Charles [University Bern, Department of Orthopedic Surgery, Inselspital, Bern (Switzerland); University Bern, Magnetic Resonance Spectroscopy and Methodology, Department of Clinical Research, Bern (Switzerland); Hughes, Timothy [Siemens Medical Solutions, Erlangen (Germany); Mosher, Timothy J. [Penn State University College of Medicine, Musculoskeletal Imaging and MRI, Department of Radiology, Hershey, PA (United States); Mueller, Christoph [University of Erlangen, Department of Trauma Surgery, Erlangen (Germany); Trattnig, Siegfried [Medical University of Vienna, MR Center - High Field MR, Department of Radiology, Vienna (Austria); Boesch, Chris [University Bern, Magnetic Resonance Spectroscopy and Methodology, Department of Clinical Research, Bern (Switzerland); Welsch, Goetz Hannes [University of Erlangen, Department of Trauma Surgery, Erlangen (Germany); Medical University of Vienna, MR Center - High Field MR, Department of Radiology, Vienna (Austria)

    2012-03-15

    T2 mapping techniques use the relaxation constant as an indirect marker of cartilage structure, and the relaxation constant has also been shown to be a sensitive parameter for cartilage evaluation. As a possible additional robust biomarker, T2* relaxation time is a potential, clinically feasible parameter for the biochemical evaluation of articular cartilage. The knees of 15 healthy volunteers and 15 patients after microfracture therapy (MFX) were evaluated with a multi-echo spin-echo T2 mapping technique and a multi-echo gradient-echo T2* mapping sequence at 3.0 Tesla MRI. Inline maps, using a log-linear least squares fitting method, were assessed with respect to the zonal dependency of T2 and T2* relaxation for the deep and superficial regions of healthy articular cartilage and cartilage repair tissue. There was a statistically significant correlation between T2 and T2* values. Both parameters demonstrated similar spatial dependency, with longer values measured toward the articular surface for healthy articular cartilage. No spatial variation was observed for cartilage repair tissue after MFX. Within this feasibility study, both T2 and T2* relaxation parameters demonstrated a similar response in the assessment of articular cartilage and cartilage repair tissue. The potential advantages of T2*-mapping of cartilage include faster imaging times and the opportunity for 3D acquisitions, thereby providing greater spatial resolution and complete coverage of the articular surface. (orig.)

  10. Multiparametric MRI of Epiphyseal Cartilage Necrosis (Osteochondrosis with Histological Validation in a Goat Model.

    Directory of Open Access Journals (Sweden)

    Luning Wang

    Full Text Available To evaluate multiple MRI parameters in a surgical model of osteochondrosis (OC in goats.Focal ischemic lesions of two different sizes were induced in the epiphyseal cartilage of the medial femoral condyles of goats at 4 days of age by surgical transection of cartilage canal blood vessels. Goats were euthanized and specimens harvested 3, 4, 5, 6, 9 and 10 weeks post-op. Ex vivo MRI scans were conducted at 9.4 Tesla for mapping the T1, T2, T1ρ, adiabatic T1ρ and TRAFF relaxation times of articular cartilage, unaffected epiphyseal cartilage, and epiphyseal cartilage within the area of the induced lesion. After MRI scans, safranin O staining was conducted to validate areas of ischemic necrosis induced in the medial femoral condyles of six goats, and to allow comparison of MRI findings with the semi-quantitative proteoglycan assessment in corresponding safranin O-stained histological sections.All relaxation time constants differentiated normal epiphyseal cartilage from lesions of ischemic cartilage necrosis, and the histological staining results confirmed the proteoglycan (PG loss in the areas of ischemia. In the scanned specimens, all of the measured relaxation time constants were higher in the articular than in the normal epiphyseal cartilage, consistently allowing differentiation between these two tissues.Multiparametric MRI provided a sensitive approach to discriminate between necrotic and viable epiphyseal cartilage and between articular and epiphyseal cartilage, which may be useful for diagnosing and monitoring OC lesions and, potentially, for assessing effectiveness of treatment interventions.

  11. Aims and Formats of performance measurement at Danish Universities

    DEFF Research Database (Denmark)

    Raffnsøe-Møller, Morten

    2011-01-01

    Abstract This article traces the aims and formats of performance measurement of Danish Universities as they originate from the Ministry of Finance’s plan for governance of the public sector. The article further show that the fierce conflicts between central administration and the universities ove...

  12. Quantitative assessment of optical properties in healthy cartilage and repair tissue by optical coherence tomography and histology (Conference Presentation)

    Science.gov (United States)

    Jansen, Sanne M. A.; Cernohorsky, Paul; de Bruin, Daniel M.; van der Pol, Edwin; Savci-Heijink, Cemile D.; Strackee, Simon D.; Faber, Dirk J.; van Leeuwen, Ton G.

    2016-02-01

    Quantification of the OCT signal is an important step toward clinical implementation of a diagnostic tool in cartilage imaging. Discrimination of structural cartilage differences in patients with osteoarthritis is critical, yet challenging. This study assesses the variation in the optical attenuation coefficient (μOCT) between healthy cartilage, repair tissue, bone and layers within repair tissue in a controlled setting. OCT and histology was used to assess goat talus articular surfaces in which central osteochondral defects were created. Exact matches of OCT and histology were selected for research. μOCT measurements were taken from healthy cartilage, repair tissue and bone. Measured μOCT in healthy cartilage was higher compared to both repair tissue and bone tissue. Two possible mechanisms for the difference in attenuation were investigated. We studied morphological parameters in terms of nucleus count, nucleus size and inter-nucleus distance. Collagen content in healthy cartilage and repair tissue was assessed using polarization microscopy. Quantitative analysis of the nuclei did not demonstrate a difference in nucleus size and count between healthy cartilage and repair tissue. In healthy cartilage, cells were spaced farther apart and had a lower variation in local nuclear density compared to repair tissue. Polarization microscopy suggested higher collagen content in healthy cartilage compared to repair tissue. μOCT measurements can distinguish between healthy cartilage, repair tissue and bone. Results suggest that cartilage OCT attenuation measurements could be of great impact in clinical diagnostics of osteoarthritis.

  13. Shear loading of costal cartilage

    CERN Document Server

    Subit, Damien

    2014-01-01

    A series of tests were performed on a single post-mortem human subject at various length scales. First, tabletop tests were performed. Next, the ribs and intercostal muscles were tested with the view to characterize the load transfer between the ribs. Finally, the costal cartilage was tested under shear loading, as it plays an important in the transfer of the load between the ribs and the sternum. This paper reports the results of dynamic shear loading tests performed on three samples of costal cartilage harvested from a single post-mortem human subject, as well as the quantification of the effective Young's modulus estimated from the amount of cartilage calcification.

  14. Comparative digital cartilage histology for human and common osteoarthritis models

    Directory of Open Access Journals (Sweden)

    Pedersen DR

    2013-02-01

    Full Text Available Douglas R Pedersen, Jessica E Goetz, Gail L Kurriger, James A MartinDepartment of Orthopaedics and Rehabilitation, University of Iowa, Iowa City, IA, USAPurpose: This study addresses the species-specific and site-specific details of weight-bearing articular cartilage zone depths and chondrocyte distributions among humans and common osteoarthritis (OA animal models using contemporary digital imaging tools. Histological analysis is the gold-standard research tool for evaluating cartilage health, OA severity, and treatment efficacy. Historically, evaluations were made by expert analysts. However, state-of-the-art tools have been developed that allow for digitization of entire histological sections for computer-aided analysis. Large volumes of common digital cartilage metrics directly complement elucidation of trends in OA inducement and concomitant potential treatments.Materials and methods: Sixteen fresh human knees, 26 adult New Zealand rabbit stifles, and 104 bovine lateral plateaus were measured for four cartilage zones and the cell densities within each zone. Each knee was divided into four weight-bearing sites: the medial and lateral plateaus and femoral condyles.Results: One-way analysis of variance followed by pairwise multiple comparisons (Holm–Sidak method at a significance of 0.05 clearly confirmed the variability between cartilage depths at each site, between sites in the same species, and between weight-bearing articular cartilage definitions in different species.Conclusion: The present study clearly demonstrates multisite, multispecies differences in normal weight-bearing articular cartilage, which can be objectively quantified by a common digital histology imaging technique. The clear site-specific differences in normal cartilage must be taken into consideration when characterizing the pathoetiology of OA models. Together, these provide a path to consistently analyze the volume and variety of histologic slides necessarily generated

  15. Specific premature epigenetic aging of cartilage in osteoarthritis

    Science.gov (United States)

    Vidal-Bralo, Laura; Lopez-Golan, Yolanda; Mera-Varela, Antonio; Rego-Perez, Ignacio; Horvath, Steve; Zhang, Yuhua; del Real, Álvaro; Zhai, Guangju; Blanco, Francisco J; Riancho, Jose A.; Gomez-Reino, Juan J; Gonzalez, Antonio

    2016-01-01

    Osteoarthritis (OA) is a disease affecting multiple tissues of the joints in the elderly, but most notably articular cartilage. Premature biological aging has been described in this tissue and in blood cells, suggesting a systemic component of premature aging in the pathogenesis of OA. Here, we have explored epigenetic aging in OA at the local (cartilage and bone) and systemic (blood) levels. Two DNA methylation age-measures (DmAM) were used: the multi-tissue age estimator for cartilage and bone; and a blood-specific biomarker for blood. Differences in DmAM between OA patients and controls showed an accelerated aging of 3.7 years in articular cartilage (95 % CI = 1.1 to 6.3, P = 0.008) of OA patients. By contrast, no difference in epigenetic aging was observed in bone (0.04 years; 95 % CI = −1.8 to 1.9, P = 0.3) and in blood (−0.6 years; 95 % CI = −1.5 to 0.3, P = 0.2) between OA patients and controls. Therefore, premature epigenetic aging according to DNA methylation changes was specific of OA cartilage, adding further evidence and insight on premature aging of cartilage as a component of OA pathogenesis that reflects damage and vulnerability. PMID:27689435

  16. Morphometric study of cricoid cartilages in Western India

    Directory of Open Access Journals (Sweden)

    Mohini Joshi

    2011-10-01

    Full Text Available BackgroundIt is important to determine the size and proportion of thelarynx as such information is useful in procedures such asintubation, endoscopy and surgical manipulations. Recentinterest in the cases of subglottic stenosis and postintubationalstenosis of the lower respiratory tract has ledto renewed interest in ascertaining the measurements ofthe various laryngeal cartilages. The aim of the presentstudy was to collect morphometric data of cricoid cartilagefrom a regional population.MethodFifty laryngeal preparations from adult cadavers of WesternIndia were assessed. Sections were prepared via dissectionand the removed cricoid cartilages then measured andweighed.ResultsThe mean antero-posterior diameter (19.29±2.47 of thecricoid cartilage was greater than the average transversediameter (18.33±2.26. The height of arch of cricoidcartilage was 6.54±1.23mm and height of lamina was21.45±1.97mm. Mean weight of cricoid cartilage was4.53±1.27grams. The shape of the cricoid cartilage wasovoid in 46% of cases, oval in 38%, pear shaped in 12% andnarrow-oblong in 4% of cases.ConclusionInter-subject variability in the dimensions of cricoidcartilages was observed. The large difference in almost allsizes and shapes of the cricoid cartilage makes it difficult tostandardise the rigid stents used in these organs.Endotracheal tubes of the appropriate size should thereforebe based on the measurements of individual patients.Clinicians should therefore be aware of morphologicalvariations as they are of fundamental clinical importance.Key WordsCricoid cartilage, larynx, morphometry

  17. Electrospun gelatin/polycaprolactone nanofibrous membranes combined with a coculture of bone marrow stromal cells and chondrocytes for cartilage engineering

    Directory of Open Access Journals (Sweden)

    He X

    2015-03-01

    Full Text Available Xiaomin He,1,* Bei Feng,1,2,* Chuanpei Huang,1 Hao Wang,1 Yang Ge,1 Renjie Hu,1 Meng Yin,1 Zhiwei Xu,1 Wei Wang,1 Wei Fu,1,2 Jinghao Zheng1 1Department of Pediatric Cardiothoracic Surgery, 2Institute of Pediatric Translational Medicine, Shanghai Children’s Medical Center School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: Electrospinning has recently received considerable attention, showing notable potential as a novel method of scaffold fabrication for cartilage engineering. The aim of this study was to use a coculture strategy of chondrocytes combined with electrospun gelatin/polycaprolactone (GT/PCL membranes, instead of pure chondrocytes, to evaluate the formation of cartilaginous tissue. We prepared the GT/PCL membranes, seeded bone marrow stromal cell (BMSC/chondrocyte cocultures (75% BMSCs and 25% chondrocytes in a sandwich model in vitro, and then implanted the constructs subcutaneously into nude mice for 12 weeks. Gross observation, histological and immunohistological evaluation, glycosaminoglycan analyses, Young’s modulus measurement, and immunofluorescence staining were performed postimplantation. We found that the coculture group formed mature cartilage-like tissue, with no statistically significant difference from the chondrocyte group, and labeled BMSCs could differentiate into chondrocyte-like cells under the chondrogenic niche of chondrocytes. This entire strategy indicates that GT/PCL membranes are also a suitable scaffold for stem cell-based cartilage engineering and may provide a potentially clinically feasible approach for cartilage repairs. Keywords: electrospinning, nanocomposite, cartilage tissue engineering, nanomaterials, stem cells

  18. Noninvasive determination of knee cartilage deformation during jumping.

    Science.gov (United States)

    Filipovic, Nenad; Vulovic, Radun; Peulic, Aleksandar; Radakovic, Radivoje; Kosanic, Djordje; Ristic, Branko

    2009-01-01

    The purpose of this investigation was to use a combination of image processing, force measurements and finite element modeling to calculate deformation of the knee cartilage during jumping. Professional athletes performed jumps analyzed using a force plate and high-speed video camera system. Image processing was performed on each frame of video using a color recognition algorithm. A simplified mass-spring-damper model was utilized for determination of global force and moment on the knee. Custom software for fitting the coupling characteristics was created. Simulated results were used as input data for the finite element calculation of cartilage deformation in the athlete's knee. Computer simulation data was compared with the average experimental ground reaction forces. The results show the three-dimensional mechanical deformation distribution inside the cartilage volume. A combination of the image recognition technology, force plate measurements and the finite element cartilage deformation in the knee may be used in the future as an effective noninvasive tool for prediction of injury during jumping. Key pointsEven there are many existing mathematical models of force distribution during running or jumping (Liu et al, 1998), to our knowledge there is no interdisciplinary approach where imaging processing, finite element modeling and experimental force plate system are employed.The aim is to explore noninvasive deformation in the knee cartilage during athlete's jumping on the force plate.An original image algorithms and software were developed as well as complex mathematical models using high-performance computational power of finite element modeling together with one-dimensional dynamics model.The initial results showed cartilage deformation in the knee and future research will be focused on the methodology and more precisely determination of the stress and strain distribution in the knee cartilage during training phase of sportsman. PMID:24149600

  19. Measurement of the Formation Rate of Muonic Hydrogen Molecules

    CERN Document Server

    Andreev, V A; Carey, R M; Case, T A; Clayton, S M; Crowe, K M; Deutsch, J; Egger, J; Freedman, S J; Ganzha, V A; Gorringe, T; Gray, F E; Hertzog, D W; Hildebrandt, M; Kammel, P; Kiburg, B; Knaack, S; Kravtsov, P A; Krivshich, A G; Lauss, B; Lynch, K R; Maev, E M; Maev, O E; Mulhauser, F; Petitjean, C; Petrov, G E; Prieels, R; Schapkin, G N; Semenchuk, G G; Soroka, M A; Tishchenko, V; Vasilyev, A A; Vorobyov, A A; Vznuzdaev, M E; Winter, P

    2015-01-01

    Background: The rate \\lambda_pp\\mu\\ characterizes the formation of pp\\mu\\ molecules in collisions of muonic p\\mu\\ atoms with hydrogen. In measurements of the basic weak muon capture reaction on the proton to determine the pseudoscalar coupling g_P, capture occurs from both atomic and molecular states. Thus knowledge of \\lambda_pp\\mu\\ is required for a correct interpretation of these experiments. Purpose: Recently the MuCap experiment has measured the capture rate \\Lambda_S from the singlet p\\mu\\ atom, employing a low density active target to suppress pp\\mu\\ formation (PRL 110, 12504 (2013)). Nevertheless, given the unprecedented precision of this experiment, the existing experimental knowledge in \\lambda_pp\\mu\\ had to be improved. Method: The MuCap experiment derived the weak capture rate from the muon disappearance rate in ultra-pure hydrogen. By doping the hydrogen with 20 ppm of argon, a competing process to pp\\mu\\ formation was introduced, which allowed the extraction of \\lambda_pp\\mu\\ from the observed t...

  20. Mechanical loading of knee articular cartilage induced by muscle contraction can be assessed by measuring electrical potentials at the surface of the knee.

    Science.gov (United States)

    Zhu, Lin; Buschmann, Michael D; Savard, Pierre

    2016-02-01

    Electroarthrography (EAG) consists of recording electrical potentials on the knee surface that originate from streaming potentials within articular cartilage while the joint is undergoing compressive loading. The aim was to investigate how the contraction of specific leg muscles affects the contact force of the knee joint and, in turn, the EAG values. For six normal subjects, voluntary isometric muscle contractions were repeatedly conducted to activate four leg muscle groups while the subject was lying on his back. Two EAG signals were recorded on the medial and lateral sides of the knee, as well as four EMG signals (gastrocnemius, hamstring, quadriceps, tensor fascia latae), and the signal from a force plate fixed against the foot according to the direction of the force. The EAG and force signals were very well correlated: the median of the correlation coefficients between an EAG signal and the corresponding force signal during each loading cycle was 0.91, and 86% of the correlation coefficients were statistically significant (pmuscle contraction was possible for the gastrocnemius and hamstring, but not always for the quadriceps and tensor fascia latae. Using the clinical loading protocol which consists of a one-legged stance, the quadriceps and hamstring EMGs showed minimal activity; loading cycles with increased EAG amplitude were associated with higher EMG activity from the gastrocnemius, which is involved in antero-posterior balance. These results document the role of the EAG as a "sensor" of the knee contact force and contribute to the development of clinical loading protocols with improved reproducibility.

  1. Repair of the superior sulcus deformity using autogenous costal cartilage.

    Science.gov (United States)

    Sutula, F C; Thomas, O

    1982-05-01

    Superior sulcus deformity is a late sequela of surgical anophthalmos. Many methods have been proposed to treat this difficult problem. A technique using autogenous costal cartilage that has resulted in satisfactory repair is presented. In addition to standard photographs and exophthalmometry measurements to follow these patients, a specific device to accurately measure orbital volume gain after operation was fashioned. PMID:7099560

  2. Preserved irradiated homologous cartilage for orbital reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Linberg, J.V.; Anderson, R.L.; Edwards, J.J.; Panje, W.R.; Bardach, J.

    1980-07-01

    Human costal cartilage is an excellent implant material for orbital and periorbital reconstruction because of its light weight, strength, homogeneous consistency and the ease with which it can be carved. Its use has been limited by the necessity of a separate surgical procedure to obtain the material. Preserved irradiated homologous cartilage has been shown to have almost all the autogenous cartilage and is convenient to use. Preserved irradiated homologous cartilage transplants do not elicit rejection reactions, resist infection and rarely undergo absorption.

  3. Transcriptomic profiling of cartilage ageing

    Directory of Open Access Journals (Sweden)

    Mandy Jayne Peffers

    2014-12-01

    Full Text Available The musculoskeletal system is severely affected by the ageing process, with many tissues undergoing changes that lead to loss of function and frailty. Articular cartilage is susceptible to age related diseases, such as osteoarthritis. Applying RNA-Seq to young and old equine cartilage, we identified an over-representation of genes with reduced expression relating to extracellular matrix, degradative proteases, matrix synthetic enzymes, cytokines and growth factors in cartilage from older donors. Here we describe the contents and quality controls in detail for the gene expression and related results published by Peffers and colleagues in Arthritis Research and Therapy 2013 associated with the data uploaded to ArrayExpress (E-MTAB-1386.

  4. Transcriptomic profiling of cartilage ageing.

    Science.gov (United States)

    Peffers, Mandy Jayne; Liu, Xuan; Clegg, Peter David

    2014-12-01

    The musculoskeletal system is severely affected by the ageing process, with many tissues undergoing changes that lead to loss of function and frailty. Articular cartilage is susceptible to age related diseases, such as osteoarthritis. Applying RNA-Seq to young and old equine cartilage, we identified an over-representation of genes with reduced expression relating to extracellular matrix, degradative proteases, matrix synthetic enzymes, cytokines and growth factors in cartilage from older donors. Here we describe the contents and quality controls in detail for the gene expression and related results published by Peffers and colleagues in Arthritis Research and Therapy 2013 associated with the data uploaded to ArrayExpress (E-MTAB-1386). PMID:26484061

  5. First evidence of dinosaurian secondary cartilage in the post-hatching skull of Hypacrosaurus stebingeri (Dinosauria, Ornithischia.

    Directory of Open Access Journals (Sweden)

    Alida M Bailleul

    Full Text Available Bone and calcified cartilage can be fossilized and preserved for hundreds of millions of years. While primary cartilage is fairly well studied in extant and fossilized organisms, nothing is known about secondary cartilage in fossils. In extant birds, secondary cartilage arises after bone formation during embryonic life at articulations, sutures and muscular attachments in order to accommodate mechanical stress. Considering the phylogenetic inclusion of birds within the Dinosauria, we hypothesized a dinosaurian origin for this "avian" tissue. Therefore, histological thin sectioning was used to investigate secondary chondrogenesis in disarticulated craniofacial elements of several post-hatching specimens of the non-avian dinosaur Hypacrosaurus stebingeri (Ornithischia, Lambeosaurinae. Secondary cartilage was found on three membrane bones directly involved with masticatory function: (1 as nodules on the dorso-caudal face of a surangular; and (2 on the bucco-caudal face of a maxilla; and (3 between teeth as islets in the alveolar processes of a dentary. Secondary chondrogenesis at these sites is consistent with the locations of secondary cartilage in extant birds and with the induction of the cartilage by different mechanical factors - stress generated by the articulation of the quadrate, stress of a ligamentous or muscular insertion, and stress of tooth formation. Thus, our study reveals the first evidence of "avian" secondary cartilage in a non-avian dinosaur. It pushes the origin of this "avian" tissue deep into dinosaurian ancestry, suggesting the creation of the more appropriate term "dinosaurian" secondary cartilage.

  6. First evidence of dinosaurian secondary cartilage in the post-hatching skull of Hypacrosaurus stebingeri (Dinosauria, Ornithischia).

    Science.gov (United States)

    Bailleul, Alida M; Hall, Brian K; Horner, John R

    2012-01-01

    Bone and calcified cartilage can be fossilized and preserved for hundreds of millions of years. While primary cartilage is fairly well studied in extant and fossilized organisms, nothing is known about secondary cartilage in fossils. In extant birds, secondary cartilage arises after bone formation during embryonic life at articulations, sutures and muscular attachments in order to accommodate mechanical stress. Considering the phylogenetic inclusion of birds within the Dinosauria, we hypothesized a dinosaurian origin for this "avian" tissue. Therefore, histological thin sectioning was used to investigate secondary chondrogenesis in disarticulated craniofacial elements of several post-hatching specimens of the non-avian dinosaur Hypacrosaurus stebingeri (Ornithischia, Lambeosaurinae). Secondary cartilage was found on three membrane bones directly involved with masticatory function: (1) as nodules on the dorso-caudal face of a surangular; and (2) on the bucco-caudal face of a maxilla; and (3) between teeth as islets in the alveolar processes of a dentary. Secondary chondrogenesis at these sites is consistent with the locations of secondary cartilage in extant birds and with the induction of the cartilage by different mechanical factors - stress generated by the articulation of the quadrate, stress of a ligamentous or muscular insertion, and stress of tooth formation. Thus, our study reveals the first evidence of "avian" secondary cartilage in a non-avian dinosaur. It pushes the origin of this "avian" tissue deep into dinosaurian ancestry, suggesting the creation of the more appropriate term "dinosaurian" secondary cartilage. PMID:22558351

  7. PHOTOCROSSLINKABLE HYDROGELS FOR CARTILAGE TISSUE ENGINEERING

    NARCIS (Netherlands)

    Levett, Peter Andrew

    2015-01-01

    For millions of people, damaged cartilage is a major source of pain and disability. As those people often discover upon seeking medical treatment, once damaged, cartilage is very difficult to repair. Finding better clinical therapies for damaged cartilage has generated a huge amount of research inte

  8. Biomaterial and Cell Based Cartilage Repair

    NARCIS (Netherlands)

    Zhao, X

    2015-01-01

    Injuries to human native cartilage tissue are particularly troublesome because cartilage has little ability to heal or regenerate itself. The reconstruction, repair, and regeneration of cartilage tissue continue to be one of the greatest clinical challenges, especially in orthopaedic and plastic sur

  9. Surgical correction of joint deformities and hyaline cartilage regeneration

    Directory of Open Access Journals (Sweden)

    Vyacheslav Alexandrovich Vinokurov

    2015-12-01

    Full Text Available Aim. To determine a method of extra-articular osteochondral fragment formation for the improvement of surgical correction results of joint deformities and optimization of regenerative conditions for hyaline cartilage. Materials and Methods. The method of formation of an articular osteochondral fragment without penetration into the joint cavity was devised experimentally. More than 30 patients with joint deformities underwent the surgery. Results. During the experiments, we postulated that there may potentially be a complete recovery of joint defects because of hyaline cartilage regeneration. By destructing the osteochondral fragment and reforming it extra-articularally, joint defects were recovered in all patients. The results were evaluated as excellent and good in majority of the patients. Conclusion. These findings indicate a novel method in which the complete recovery of joint defects due to dysplastic genesis or osteochondral defects as a result of injuries can be obtained. The devised method can be used in future experiments for objectification and regenerative potential of hyaline cartilage (e.g., rate and volume of the reformed joints that regenerate, detection of cartilage elements, and the regeneration process.

  10. Isolation, identification, and comparison of cartilage stem progenitor/cells from auricular cartilage and perichondrium

    OpenAIRE

    Xue, Ke; Zhang, Xiaodie; Qi, Lin; Zhou, Jia; Liu, Kai

    2016-01-01

    Auricular cartilage loss or defect remains a challenge to plastic surgeons, and cartilage regenerative medicine provides a novel method to solve the problem. However, ideal seeding cells seem to be the key point in the development of cartilage regeneration. Although bone marrow-mesenchymal stem cells were considered as the ideal seeding cells in cartilage regeneration, regenerative cartilage differentiated from bone marrow-mesenchymal stem cells still faces some problems. It is reported that ...

  11. Evidence for a negative Pasteur effect in articular cartilage.

    Science.gov (United States)

    Lee, R B; Urban, J P

    1997-01-01

    Uptake of external glucose and production of lactate were measured in freshly-excised bovine articular cartilage under O2 concentrations ranging from 21% (air) to zero (N2-bubbled). Anoxia (O2 concentration Pasteur effect in bovine articular cartilage. Anoxia also suppressed glycolysis in articular cartilage from horse, pig and sheep. Inhibitors acting on the glycolytic pathway (2-deoxy-D-glucose, iodoacetamide or fluoride) strongly decreased aerobic lactate production and ATP concentration, consistent with the belief that articular cartilage obtains its principal supply of ATP from substrate-level phosphorylation in glycolysis. Azide or cyanide lowered the ATP concentration in aerobic cartilage to approximately the same extent as did anoxia but, because glycolysis (lactate production) was also inhibited by these treatments, the importance of any mitochondrial ATP production could not be assessed. A negative Pasteur effect would make chondrocytes particularly liable to suffer a shortage of energy under anoxic conditions. Incorporation of [35S]sulphate into proteoglycan was severely curtailed by treatments, such as anoxia, which decreased the intracellular concentration of ATP.

  12. Measurement of Sinkhole Formation and Progression with InSAR

    Science.gov (United States)

    Jones, C. E.; Blom, R. G.

    2013-12-01

    The Bayou Corne Sinkhole initially formed in August 2012 from sidewall collapse of a brine cavern within the Napoleonville Salt Dome in southeastern Louisiana. The sinkhole, initially ~1 hectare in size, has expanded to ~10 hectare surface coverage by July 2013, as material continued to fill the subterranean void. Here we show that synthetic aperture radar (SAR) interferometry (InSAR) could have reliably forecast the formation and location of the Bayou Corne Sinkhole at least a month in advance from the large precursory surface deformation that occurred in the area where the sinkhole later formed. The Mississippi delta region has been imaged since 2009 using the NASA Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR), and radar data over the Napoleonville Salt Dome had been acquired on 2 July 2012, only a month before the sinkhole developed. Using radar interferometry, we show significant surface deformation of up to 250 mm occurred between 23 June 2011, and 2 July 2012, in an extended area encompassing the sinkhole site. The InSAR results show no measurable deformation prior to 23 June 2011. The measured precursory deformation pattern is consistent with compressive loading at the surface due to removal of support caused by a vertically oriented subsurface fracture. The measured strains relate directly to subsurface geology, salt rock properties, and internal stresses caused by the salt dome sidewall collapse. Measurements made with UAVSAR since the sinkhole formation, between August 2012 and July 2013, show progression of the surface deformation well beyond the limited extent of the sinkhole itself, with growth of the sinkhole following the direction of maximum surface deformation. These results show that even in radar-challenging environments such as the swamplands of Bayou Corne, L-band InSAR can be used to study the underlying geophysics of sinkhole formation and, furthermore, that InSAR data collected operationally for hazard monitoring could

  13. Is Formative Measurement Really Measurement? Reply to Bollen (2007) and Bagozzi (2007)

    Science.gov (United States)

    Howell, Roy D.; Breivik, Einar; Wilcox, James B.

    2007-01-01

    R. D. Howell, E. Breivik, and J. B. Wilcox (2007) examined the use of formative measurement models in theory testing in the social sciences. K. A. Bollen (2007) and R. P. Bagozzi (2007) have provided comments on this work. In this article, the authors reply to the commentators and suggest that the conclusions reached in the original article and…

  14. Are We Correctly Measuring the Star Formation in Galaxies?

    Science.gov (United States)

    McQuinn, K. B. W.; Skillman, E. D.; Dolphin, A. E.; Mitchell, N. P.

    2016-06-01

    Integrating our knowledge of star formation (SF) traced by observations at different wavelengths is essential for correctly interpreting and comparing SF activity in a variety of systems and environments. This study compares extinction corrected integrated ultraviolet (UV) emission from resolved galaxies with color-magnitude diagram (CMD) based star formation rates (SFRs) derived from resolved stellar populations and CMD fitting techniques in 19 nearby starburst and post-starburst dwarf galaxies. The data sets are from the panchromatic Starburst Irregular Dwarf Survey and include deep legacy GALEX UV imaging, Hubble Space Telescope optical imaging, and Spitzer MIPS imaging. For the majority of the sample, the integrated near-UV fluxes predicted from the CMD-based SFRs—using four different models—agree with the measured, extinction corrected, integrated near-UV fluxes from GALEX images, but the far-UV (FUV) predicted fluxes do not. Furthermore, we find a systematic deviation between the SFRs based on integrated FUV luminosities and existing scaling relations, and the SFRs based on the resolved stellar populations. This offset is not driven by different SF timescales, variations in SFRs, UV attenuation, nor stochastic effects. This first comparison between CMD-based SFRs and an integrated FUV emission SFR indicator suggests that the most likely cause of the discrepancy is the theoretical FUV-SFR calibration from stellar evolutionary libraries and/or stellar atmospheric models. We present an empirical calibration of the FUV-based SFR relation for dwarf galaxies, with uncertainties, which is 53% larger than previous relations.

  15. [Cartilage tumors : Pathology and radiomorphology].

    Science.gov (United States)

    Uhl, M; Herget, G; Kurz, P

    2016-06-01

    Primary cartilage-forming tumors of the bone are frequent entities in the daily work of skeletal radiologists. This article describes the correlation of pathology and radiology in cartilage-forming skeletal tumors, in particular, enchondroma, osteochondroma, periosteal chondromas, chondroblastoma and various forms of chondrosarcoma. After reading, the radiologist should be able to deduce the different patterns of cartilage tumors on radiographs, CT, and MRI from the pathological aspects. Differentiation of enchondroma and chondrosarcoma is a frequent diagnostic challenge. Some imaging parameters, e. g., deep cortical scalloping (more than two thirds of the cortical thickness), cortical destruction, or a soft-tissue mass, are features of a sarcoma. Osteochondromas are bony protrusions with a continuous extension of bone marrow from the parent bone, the host cortical bone runs continuously from the osseous surface of the tumor into the shaft of the osteochondroma and the osteochondroma has a cartilage cap. Chondromyxoid fibromas are well-defined lytic and eccentric lesions of the metaphysis of the long bones, with nonspecific MRI findings. Chondroblastomas have a strong predilection for the epiphysis of long tubular bones and develop an intense perifocal bone marrow edema. Dedifferentiated chondrosarcomas are bimorphic lesions with a low-grade chondrogenic component and a high-grade noncartilaginous component. Most chondrogenic tumors have a predilection with regard to site and age at manifestation. PMID:27233920

  16. Cartilage Wound Healing and Integration

    NARCIS (Netherlands)

    P.K. Bos (Koen)

    2006-01-01

    textabstractThe intrinsic regeneration capacity of articular cartilage following injury is limited. Partialthickness defects are not repaired and full-thickness defects are repaired with fi brocartilage. Untreated, these defects may progress to early osteoarthritis. The goal of surgical treatment

  17. Postnatal development of articular cartilage

    NARCIS (Netherlands)

    Turnhout, van M.C.

    2010-01-01

    Articular cartilage (AC) is the thin layer of tissue that covers the ends of the bones in the synovial joints in mammals. Functional adult AC has depth-dependent mechanical properties that are not yet present at birth. These depth-dependent mechanical properties in adult life are the result of a dep

  18. Relationship between the trochlear groove angle and patellar cartilage morphology defined by 3D spoiled gradient-echo imaging

    Energy Technology Data Exchange (ETDEWEB)

    Harada, Yuko; Tokuda, Osamu; Matsunaga, Naofumi [Yamaguchi University Graduate School of Medicine, Department of Radiology, Yamaguchi (Japan); Fukuda, Kouji [Shunan Memorial Hospital, Division of Radiological Technology, Yamaguchi (Japan); Shiraishi, Gen; Motomura, Tetsuhisa [Shunan Memorial Hospital, Department of Orthopedics Surgery, Yamaguchi (Japan); Kimura, Motoichi [Customer Application Gr., GE Healthcare MR Sales and Marketing Department, Osaka (Japan)

    2012-05-15

    To examine whether the femoral trochlear groove angle (TGA) is a determinant of the patellar cartilage volume and patellar cartilage damage. Patellar cartilage was evaluated by MR imaging in 66 patients (22 males and 44 females) with knee pain. Fat-suppressed 3D spoiled gradient-echo images were used to calculate the cartilage volume and to grade the cartilage damage. The proximal and distal TGAs were measured from axial PD-weighted FSE MR images with fat suppression. For every increase in the TGA at the distal femur, the patellar cartilage volume was significantly increased by 6.07 x 10{sup -3} cm{sup 3} (95% CI: 1.27 x 10{sup -3}, 10.9 x 10{sup -3}) after adjustment for age, gender, and patellar bone volume (P < 0.05). The MR grade of medial patellar cartilage damage progressed as the distal TGA became narrower, although there was no significant correlation between the distal TGA and the MR grading of patellar cartilage damage. A more flattened distal TGA was associated with increased patellar cartilage volume. However, there was no association between TGA and patellar cartilage defects. (orig.)

  19. Relationship between the trochlear groove angle and patellar cartilage morphology defined by 3D spoiled gradient-echo imaging

    International Nuclear Information System (INIS)

    To examine whether the femoral trochlear groove angle (TGA) is a determinant of the patellar cartilage volume and patellar cartilage damage. Patellar cartilage was evaluated by MR imaging in 66 patients (22 males and 44 females) with knee pain. Fat-suppressed 3D spoiled gradient-echo images were used to calculate the cartilage volume and to grade the cartilage damage. The proximal and distal TGAs were measured from axial PD-weighted FSE MR images with fat suppression. For every increase in the TGA at the distal femur, the patellar cartilage volume was significantly increased by 6.07 x 10-3 cm3 (95% CI: 1.27 x 10-3, 10.9 x 10-3) after adjustment for age, gender, and patellar bone volume (P < 0.05). The MR grade of medial patellar cartilage damage progressed as the distal TGA became narrower, although there was no significant correlation between the distal TGA and the MR grading of patellar cartilage damage. A more flattened distal TGA was associated with increased patellar cartilage volume. However, there was no association between TGA and patellar cartilage defects. (orig.)

  20. Friction behavior of coupling motion for natural articular cartilage by reciprocating rotation

    Institute of Scientific and Technical Information of China (English)

    QIAN ShanHua; GE ShiRong

    2009-01-01

    Based on the irregular surface of natural cartilage configurations, the tribological characteristics of coupling motion between natural cartilage pairs were investigated by the variation of rotated offset and velocity. Contact displacement, contact load, friction force and coefficient of friction from natural cartilage pairs were measured by a UMT-2 testing machine. In order to obtain the steady part and wavy part, the contact load and contact displacement were decompounded by the five-point sliding average method. These results showed that the contact load was composed of steady load and wavy load. And the contact displacement was composed of cartilage deformation and surface outline. The steady load was similar to exterior load while natural cartilage deformation increased nonlinearly with the sliding time. Wavy load had the correlative coefficient 0.235 with surface outline due to the irregular surface of fric-tion configurations. The coefficient of friction from cartilage friction configurations was less influenced by smaller magnitude in rotated parameters. A few strange summits were obtained in the area of coef-ficient of friction, and significantly related with local minimal values corresponding to the contact loads. The rotated offsets had clear impact on contact load and a slight impact on contact displacement. Larger offset produced higher wavy magnitude of the contact load. The rotated velocities played an evident role in cartilage deformation, but had a less influence on contact load. Lower velocity brought larger cartilage deformation.

  1. Characterization of enzymatically induced degradation of articular cartilage using high frequency ultrasound

    Science.gov (United States)

    Töyräs, J.; Rieppo, J.; Nieminen, M. T.; Helminen, H. J.; Jurvelin, J. S.

    1999-11-01

    Ultrasound may provide a quantitative technique for the characterization of cartilage changes typical of early osteoarthrosis. In this study, specific changes in bovine articular cartilage were induced using collagenase and chondroitinase ABC, enzymes that selectively degrade collagen fibril network and digest proteoglycans, respectively. Changes in cartilage structure and properties were quantified using high frequency ultrasound, microscopic analyses and mechanical indentation tests. The ultrasound reflection coefficient of the physiological saline-cartilage interface (R1) decreased significantly (-96.4%, pdigested cartilage compared to controls. Also a significantly lower ultrasound velocity (-6.2%, pdigestion. After chondroitinase ABC digestion, a new acoustic interface at the depth of the enzyme penetration front was detected. Cartilage thickness, as determined with ultrasound, showed a high, linear correlation (R = 0.943, n = 60, average difference 0.073 mm (4.0%)) with the thickness measured by the needle-probe method. Both enzymes induced a significant decrease in the Young's modulus of cartilage (p<0.01). Our results indicate that high frequency ultrasound provides a sensitive technique for the analysis of cartilage structure and properties. Possibly ultrasound may be utilized in vivo as a quantitative probe during arthroscopy.

  2. Evaluation of Constant Thickness Cartilage Models vs. Patient Specific Cartilage Models for an Optimized Computer-Assisted Planning of Periacetabular Osteotomy.

    Directory of Open Access Journals (Sweden)

    Li Liu

    Full Text Available Modern computerized planning tools for periacetabular osteotomy (PAO use either morphology-based or biomechanics-based methods. The latter relies on estimation of peak contact pressures and contact areas using either patient specific or constant thickness cartilage models. We performed a finite element analysis investigating the optimal reorientation of the acetabulum in PAO surgery based on simulated joint contact pressures and contact areas using patient specific cartilage model. Furthermore we investigated the influences of using patient specific cartilage model or constant thickness cartilage model on the biomechanical simulation results. Ten specimens with hip dysplasia were used in this study. Image data were available from CT arthrography studies. Bone models were reconstructed. Mesh models for the patient specific cartilage were defined and subsequently loaded under previously reported boundary and loading conditions. Peak contact pressures and contact areas were estimated in the original position. Afterwards we used a validated preoperative planning software to change the acetabular inclination by an increment of 5° and measured the lateral center edge angle (LCE at each reorientation position. The position with the largest contact area and the lowest peak contact pressure was defined as the optimal position. In order to investigate the influence of using patient specific cartilage model or constant thickness cartilage model on the biomechanical simulation results, the same procedure was repeated with the same bone models but with a cartilage mesh of constant thickness. Comparison of the peak contact pressures and the contact areas between these two different cartilage models showed that good correlation between these two cartilage models for peak contact pressures (r = 0.634 ∈ [0.6, 0.8], p 0.8, p < 0.001. For both cartilage models, the largest contact areas and the lowest peak pressures were found at the same position. Our study is

  3. Poroelasticity of cartilage at the nanoscale.

    Science.gov (United States)

    Nia, Hadi Tavakoli; Han, Lin; Li, Yang; Ortiz, Christine; Grodzinsky, Alan

    2011-11-01

    Atomic-force-microscopy-based oscillatory loading was used in conjunction with finite element modeling to quantify and predict the frequency-dependent mechanical properties of the superficial zone of young bovine articular cartilage at deformation amplitudes, δ, of ~15 nm; i.e., at macromolecular length scales. Using a spherical probe tip (R ~ 12.5 μm), the magnitude of the dynamic complex indentation modulus, |E*|, and phase angle, φ, between the force and tip displacement sinusoids, were measured in the frequency range f ~ 0.2-130 Hz at an offset indentation depth of δ(0) ~ 3 μm. The experimentally measured |E*| and φ corresponded well with that predicted by a fibril-reinforced poroelastic model over a three-decade frequency range. The peak frequency of phase angle, f(peak), was observed to scale linearly with the inverse square of the contact distance between probe tip and cartilage, 1/d(2), as predicted by linear poroelasticity theory. The dynamic mechanical properties were observed to be independent of the deformation amplitude in the range δ = 7-50 nm. Hence, these results suggest that poroelasticity was the dominant mechanism underlying the frequency-dependent mechanical behavior observed at these nanoscale deformations. These findings enable ongoing investigations of the nanoscale progression of matrix pathology in tissue-level disease. PMID:22067171

  4. 76 FR 38191 - New Proposed Collection; Comment Request; Biospecimen and Physical Measures Formative Research...

    Science.gov (United States)

    2011-06-29

    ... Physical Measures Formative Research Methodology Studies for the National Children's Study SUMMARY: In... comment questioned the cost and utility of the study and federally funded biomedical research in general...: Title: Biospecimen and Physical Measures Formative Research Methodology Studies for the...

  5. Cartilage-selective genes identified in genome-scale analysis of non-cartilage and cartilage gene expression

    Directory of Open Access Journals (Sweden)

    Cohn Zachary A

    2007-06-01

    Full Text Available Abstract Background Cartilage plays a fundamental role in the development of the human skeleton. Early in embryogenesis, mesenchymal cells condense and differentiate into chondrocytes to shape the early skeleton. Subsequently, the cartilage anlagen differentiate to form the growth plates, which are responsible for linear bone growth, and the articular chondrocytes, which facilitate joint function. However, despite the multiplicity of roles of cartilage during human fetal life, surprisingly little is known about its transcriptome. To address this, a whole genome microarray expression profile was generated using RNA isolated from 18–22 week human distal femur fetal cartilage and compared with a database of control normal human tissues aggregated at UCLA, termed Celsius. Results 161 cartilage-selective genes were identified, defined as genes significantly expressed in cartilage with low expression and little variation across a panel of 34 non-cartilage tissues. Among these 161 genes were cartilage-specific genes such as cartilage collagen genes and 25 genes which have been associated with skeletal phenotypes in humans and/or mice. Many of the other cartilage-selective genes do not have established roles in cartilage or are novel, unannotated genes. Quantitative RT-PCR confirmed the unique pattern of gene expression observed by microarray analysis. Conclusion Defining the gene expression pattern for cartilage has identified new genes that may contribute to human skeletogenesis as well as provided further candidate genes for skeletal dysplasias. The data suggest that fetal cartilage is a complex and transcriptionally active tissue and demonstrate that the set of genes selectively expressed in the tissue has been greatly underestimated.

  6. Healing Osteoarthritis: Engineered Proteins Created for Therapeutic Cartilage Regeneration

    Directory of Open Access Journals (Sweden)

    Kevin M. Cherry

    2012-01-01

    Full Text Available Millions of people worldwide are afflicted with painfulosteoarthritis, which is characterized by degradationof articular cartilage found in major joints such as thehip or knee. Symptoms include inflammation, pain,and decreased mobility. Because cartilage has a limitedability to self-heal, researchers have focused efforts onmethods that trigger cartilage regeneration. Our approachis to develop an injectable, protein-based hydrogel withmechanical properties analogous to healthy articularcartilage. The hydrogel provides an environment for cellgrowth and stimulates new tissue formation. We utilizedrecombinant DNA technology to create multifunctional,elastomeric proteins. The recombinant proteins weredesigned with biologically active domains to influence cellbehavior and resilin structural domains that mimic thestiffness of native cartilage. Resilin, a protein found in thewing and leg joints of mosquitoes, provided inspiration forthe mechanical domain in the recombinant protein. Thenew resilin-based protein was expressed in E. coli bacteria.Forming hydrogels requires a large quantity of engineeredprotein, so parameters such as bacterial host, incubationtemperature, expression time, and induction method wereoptimized to increase the protein yield. Using salt toprecipitate the protein and exploiting resilin’s heat stability,27 mg/L of recombinant protein was recovered at 95%purity. The protein expression and purification protocolswere established by analyzing experimental samples onSDS-PAGE gels and by Western blotting. The mechanicalproperties and interactions with stem cells are currentlybeing evaluated to assess the potential of the resilin-basedhydrogel as a treatment for osteoarthritis.

  7. Analysis of cartilage-polydioxanone foil composite grafts.

    Science.gov (United States)

    Kim, James H; Wong, Brian

    2013-12-01

    This study presents an analytical investigation into the mechanical behavior of a cartilage-polydioxanone (PDS) plate composite grafts. Numerical methods are used to provide a first-order, numerical model of the flexural stiffness of a cartilage-PDS graft. Flexural stiffness is a measure of resistance to bending and is inversely related to the amount of deformation a structure may experience when subjected to bending forces. The cartilage-PDS graft was modeled as a single composite beam. Using Bernoulli-Euler beam theory, a closed form equation for the theoretical flexural stiffness of the composite graft was developed. A parametric analysis was performed to see how the flexural properties of the composite model changed with varying thicknesses of PDS foil. The stiffness of the cartilage-PDS composite using 0.15-mm-thick PDS was four times higher than cartilage alone. The composite with a 0.5-mm-thick PDS graft was only 1.7 times stiffer than the composite with the 0.15-mm-thick PDS graft. Although a thicker graft material will yield higher flexural stiffness for the composite, the relationship between composite stiffness and PDS thickness is nonlinear. After a critical point, increments in graft thickness produce gradually smaller improvements in flexural stiffness. The small increase in stiffness when using the thicker PDS foils versus the 0.15 mm PDS foil may not be worth the potential complications (prolonged foreign body reaction, reduction in nutrient diffusion to cartilage) of using thicker artificial grafts. PMID:24327249

  8. Cartilage Derived from Bone Marrow Mesenchymal Stem Cells Expresses Lubricin In Vitro and In Vivo.

    Directory of Open Access Journals (Sweden)

    Yusuke Nakagawa

    Full Text Available Lubricin expression in the superficial cartilage will be a crucial factor in the success of cartilage regeneration. Mesenchymal stem cells (MSCs are an attractive cell source and the use of aggregates of MSCs has some advantages in terms of chondrogenic potential and efficiency of cell adhesion. Lubricin expression in transplanted MSCs has not been fully elucidated so far. Our goals were to determine (1 whether cartilage pellets of human MSCs expressed lubricin in vitro chondrogenesis, (2 whether aggregates of human MSCs promoted lubricin expression, and (3 whether aggregates of MSCs expressed lubricin in the superficial cartilage after transplantation into osteochondral defects in rats.For in vitro analysis, human bone marrow (BM MSCs were differentiated into cartilage by pellet culture, and also aggregated using the hanging drop technique. For an animal study, aggregates of BM MSCs derived from GFP transgenic rats were transplanted to the osteochondral defect in the trochlear groove of wild type rat knee joints. Lubricin expression was mainly evaluated in differentiated and regenerated cartilages.In in vitro analysis, lubricin was detected in the superficial zone of the pellets and conditioned medium. mRNA expression of Proteoglycan4 (Prg4, which encodes lubricin, in pellets was significantly higher than that of undifferentiated MSCs. Aggregates showed different morphological features between the superficial and deep zone, and the Prg4 mRNA expression increased after aggregate formation. Lubricin was also found in the aggregate. In a rat study, articular cartilage regeneration was significantly better in the MSC group than in the control group as shown by macroscopical and histological analysis. The transmission electron microscope showed that morphology of the superficial cartilage in the MSC group was closer to that of the intact cartilage than in the control group. GFP positive cells remained in the repaired tissue and expressed lubricin in

  9. Induction of inflammatory cytokines by cartilage extracts.

    Science.gov (United States)

    Merly, Liza; Simjee, Shabana; Smith, Sylvia L

    2007-03-01

    Shark cartilage extracts were examined for induction of cytokines and chemokines in human peripheral blood leukocytes. Primary leukocyte cultures were exposed to a variety of aqueous and organic extracts prepared from several commercial brands of shark cartilage. From all commercial sources of shark cartilage tested the acid extracts induced higher levels of TNFalpha than other extracts. Different commercial brands of shark cartilage varied significantly in cytokine-inducing activity. TNFalpha induction was seen as early as 4 h and IFNgamma at detectable levels for up to four days. Shark cartilage extracts did not induce physiologically significant levels of IL-4. Results suggest that shark cartilage, preferentially, induces Th1 type inflammatory cytokines. When compared to bovine cartilage extract, collagen, and chondroitin sulfate, shark cartilage induced significantly higher levels of TNFalpha. Treatment with digestive proteases (trypsin and chymotrypsin) reduced the cytokine induction response by 80%, suggesting that the active component(s) in cartilage extracts is proteinaceous. The induction of Th1 type cytokine response in leukocytes is a significant finding since shark cartilage, taken as a dietary supplement for a variety of chronic degenerative diseases, would be contraindicated in cases where the underlying pathology of the chronic condition is caused by inflammation. PMID:17276897

  10. The study on the mechanical characteristics of articular cartilage in simulated microgravity

    Institute of Scientific and Technical Information of China (English)

    Hai-Jun Niu; Qing Wang; Yue-Xiang Wang; Ang Li; Lian-Wen Sun; Yan Yan; Fan Fan; De-Yu Li; Yu-Bo Fan

    2012-01-01

    The microgravity environment of a long-term space flight may induce acute changes in an astronaut's musculo-skeletal systems.This study explores the effects of simulated microgravity on the mechanical characteristics of articular cartilage.Six rats underwent tail suspension for 14 days and six additional rats were kept under normal earth gravity as controls.Swelling strains were measured using high-frequency ultrasound in all cartilage samples subject to osmotic loading.Site-specific swelling strain data were used in a triphasic theoretical model of cartilage swelling to determine the uniaxial modulus of the cartilage solid matrix.No severe surface irregularities were found in the cartilage samples obtained from the control or tail-suspended groups.For the tail-suspended group,the thickness of the cartilage at a specified site,as determined by ultrasound echo,showed a minor decrease.The uniaxial modulus of articular cartilage at the specified site decreased significantly,from (6.31 ± 3.37) MPa to (5.05 ± 2.98) MPa (p < 0.05).The histology-stained image of a cartilage sample also showed a reduced number of chondrocytes and decreased degree of matrix staining.These results demonstrated that the 14 d simulated microgravity induced significant effects on the mechanical characteristics of articular cartilage.This study is the first attempt to explore the effects of simulated microgravity on the mechanical characteristics of articular cartilage using an osmotic loading method and a triphasic model.The conclusions may provide reference information for manned space flights and a better understanding of the effects of microgravity on the skeletal system.

  11. Holmium laser ablation of cartilage: effects of cavitation bubbles

    Science.gov (United States)

    Asshauer, Thomas; Jansen, Thomas; Oberthur, Thorsten; Delacretaz, Guy P.; Gerber, Bruno E.

    1995-05-01

    The ablation of fresh harvested porcine femur patellar groove cartilage by a 2.12 micrometers Cr:Tm:Ho:YAG laser in clinically used irradiation conditions was studied. Laser pulses were delivered via a 600 micrometers diameter fiber in isotonic saline. Ablation was investigated as a function of the angle of incidence of the delivery fiber with respect to the cartilage surface (0-90 degrees) and of radiant exposure. Laser pulses with energies of 0.5, 1.0 and 1.5 J and a duration of 250 microseconds were used. A constant fiber tip-tissue distance of 1 mm was maintained for all experiments. The dynamics of the induced vapor bubble and of the ablation process was monitored by time resolved flash videography with a 1 microseconds illumination. Acoustic transients were measured with a piezoelectric PVDF needle probe hydrophone. Bubble attachment to the cartilage surface during the collapse phase, leading to the direct exposition of the cartilage surface to the maximal pressure generated, was observed in all investigated irradiation conditions. Maximal pressure transients of up to 200 bars (at 1 mm distance from the collapse center) were measured at the bubble collapse at irradiation angles >= 60 degrees. No significant pressure variation was observed in perpendicular irradiation conditions as a function of radiant exposure. A significant reduction of the induced pressure for irradiation angles

  12. Multinuclear nuclear magnetic resonance spectroscopic study of cartilage proteoglycans

    International Nuclear Information System (INIS)

    Hyaline cartilage is a composite material whose major function is to withstand compression while retaining flexibility. Its mechanical properties are affected by tissue hydration and ionic composition. Models of the mechanical behavior of cartilage have incorporated certain assumptions about the interactions of the major components of cartilage: collagen, proteoglycans, water, and cations. To determine the validity of these assumption, the authors have used nuclear magnetic resonance spectroscopy (NMR). Two approaches have been used: (a) natural abundance carbon-13 NMR; and (b) NMR of sodium-23, potassium-39, magnesium-25, and calcium-43. Evidence from studies in intact tissues are reinforced by extensive measurements on solutions of proteoglycans and other relevant macromolecules. Based on the measurements of NMR relaxation rates and lineshapes reported here, it is concluded that neither sodium nor potassium interact strongly with bovine nasal proteoglycan aggregates or their substituent glycosaminoglycan chains in solution. Proteoglycans do bind magnesium and calcium. Therefore there is a qualitative difference between monovalent and divalent cations, which is not taken into account by polyelectrolyte models or models for the ionic dependence of mechanical properties. Cation binding to heparin, which has a higher charge density than cartilage proteoglycans, was also studied. The results presented here establish that heparin binds sodium, magnesium, and calcium

  13. Fetal mesenchymal stromal cells differentiating towards chondrocytes acquire a gene expression profile resembling human growth plate cartilage.

    Directory of Open Access Journals (Sweden)

    Sandy A van Gool

    Full Text Available We used human fetal bone marrow-derived mesenchymal stromal cells (hfMSCs differentiating towards chondrocytes as an alternative model for the human growth plate (GP. Our aims were to study gene expression patterns associated with chondrogenic differentiation to assess whether chondrocytes derived from hfMSCs are a suitable model for studying the development and maturation of the GP. hfMSCs efficiently formed hyaline cartilage in a pellet culture in the presence of TGFβ3 and BMP6. Microarray and principal component analysis were applied to study gene expression profiles during chondrogenic differentiation. A set of 232 genes was found to correlate with in vitro cartilage formation. Several identified genes are known to be involved in cartilage formation and validate the robustness of the differentiating hfMSC model. KEGG pathway analysis using the 232 genes revealed 9 significant signaling pathways correlated with cartilage formation. To determine the progression of growth plate cartilage formation, we compared the gene expression profile of differentiating hfMSCs with previously established expression profiles of epiphyseal GP cartilage. As differentiation towards chondrocytes proceeds, hfMSCs gradually obtain a gene expression profile resembling epiphyseal GP cartilage. We visualized the differences in gene expression profiles as protein interaction clusters and identified many protein clusters that are activated during the early chondrogenic differentiation of hfMSCs showing the potential of this system to study GP development.

  14. Mechanobiology and Cartilage Tissue Engineering

    Institute of Scientific and Technical Information of China (English)

    Céline; HUSELSTEIN; Natalia; de; ISLA; Sylvaine; MULLER; Jean-Franois; STOLTZ

    2005-01-01

    1 IntroductionThe cartilage is a hydrated connective tissue in joints that withstands and distributes mechanical forces. Chondrocytes utilize mechanical signals to maintain tissue homeostasis. They regulate their metabolic activity through complex biological and biophysical interactions with the extracellular matrix (ECM). Although some of the mechanisms of mechanotransduction are known today, there are certainly many others left unrevealed. Different topics of chondrocytes mechanobiology have led to the de...

  15. Preclinical Studies for Cartilage Repair

    OpenAIRE

    Hurtig, Mark B.; Buschmann, Michael D; Fortier, Lisa A; Hoemann, Caroline D; Hunziker, Ernst B.; Jurvelin, Jukka S.; Mainil-Varlet, Pierre; McIlwraith, C. Wayne; Sah, Robert L.; Whiteside, Robert A.

    2011-01-01

    Investigational devices for articular cartilage repair or replacement are considered to be significant risk devices by regulatory bodies. Therefore animal models are needed to provide proof of efficacy and safety prior to clinical testing. The financial commitment and regulatory steps needed to bring a new technology to clinical use can be major obstacles, so the implementation of highly predictive animal models is a pressing issue. Until recently, a reductionist approach using acute chondral...

  16. Rib Cartilage Assessment Relative to the Healthy Ear in Young Children with Microtia Guiding Operative Timing

    Institute of Scientific and Technical Information of China (English)

    Shen-Song Kang; Ying Guo; Dong-Yi Zhang; Du-Yin Jiang

    2015-01-01

    Background:The optimal age at which to initiate for auricular reconstruction is controversial.Rib cartilage growth is closely related to age and determines the feasibility and outcomes of auricular reconstruction.We developed a method to guide the timing of auricular reconstruction in children with microtia ranging in age from 5 to 10 years.Methods:Rib cartilage and the healthy ear were assessed using low-dose multi-slice computed tomography.The lengths of the eighth rib cartilage and the helix of the healthy ear (from the helical crus to the joint of the helix and the earlobe) were measured.Surgery was performed when the two lengths were approximately equal.Results:The preoperative eighth rib measurements significantly correlated with the intraoperative measurements (P < 0.05).From 5 to 10 years of age,eighth rib growth was not linear.In 76 (62.8%) of 121 patients,the eighth rib length was approximately equal to the helix length in the healthy ear;satisfactory outcomes were achieved in these patients.In 18 (14.9%) patients,the eighth rib was slightly shorter than the helix,helix fabrication was accomplished by adjusting the length of the helical crus of stent,and satisfactory outcomes were also achieved.Acceptable outcomes were achieved in 17 (14.0%) patients in whom helix fabrication was accomplished by cartilage splicing.In 9 (7.4%) patients with insufficient rib cartilage length,the operation was delayed.In one (0.8%) patient with insufficient rib cartilage length,which left no cartilage for helix splicing,the result was unsatisfactory.Conclusions:Eighth rib cartilage growth is variable.Rib cartilage assessment relative to the healthy ear can guide auricular reconstruction and personalize treatment in young patients with microtia.

  17. Cartilage constructs from human cord blood stem cells seeded in structurally-graded polycaprolactone scaffolds

    DEFF Research Database (Denmark)

    Munir, Samir; Koch, Thomas Gadegaard; Foldager, Casper Bindzus;

    Cartilage is an avascular tissue incapable of regeneration. Current treatment modalities for joint cartilage injuries are inefficient in regenerating hyaline cartilage and often leads to the formation of fibrocartilage with undesirable mechanical properties. There is an increasing interest...... stimulation. This study demonstrated the chondrogenic potential of human cord blood-derived Multi-Lineage Progenitor Cells (MLPCs) under normoxic and hypoxic culture conditions. Second, MLPCs were seeded in a novel, structurally graded polycaprolactone (SGS-PCL) scaffold and chondrogenesis was evaluated...... this novel SGS-PCL scaffold supports the chondrogenic differentiation of MLPCs will be interesting to evaluate since this scaffold possesses mechanical properties absent from other “soft” scaffolds currently being investigated for cartilage regeneration and implantation....

  18. Surface modification of polycaprolactone scaffolds fabricated via selective laser sintering for cartilage tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chih-Hao [Department of Chemical and Materials Engineering, Chang Gung University, Kweishan, Taoyuan 333, Taiwan, ROC (China); Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, Craniofacial Research Center, Chang Gung University, Kweishann, Taoyuan 333, Taiwan, ROC (China); Lee, Ming-Yih [Graduate Institute of Medical Mechatronics, Chang Gung University, Kweishan, Taoyuan 333, Taiwan, ROC (China); Shyu, Victor Bong-Hang; Chen, Yi-Chieh; Chen, Chien-Tzung [Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, Craniofacial Research Center, Chang Gung University, Kweishann, Taoyuan 333, Taiwan, ROC (China); Chen, Jyh-Ping, E-mail: jpchen@mail.cgu.edu.tw [Department of Chemical and Materials Engineering, Chang Gung University, Kweishan, Taoyuan 333, Taiwan, ROC (China); Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Kweishan, Taoyuan 333, Taiwan, ROC (China)

    2014-07-01

    Surface modified porous polycaprolactone scaffolds fabricated via rapid prototyping techniques were evaluated for cartilage tissue engineering purposes. Polycaprolactone scaffolds manufactured by selective laser sintering (SLS) were surface modified through immersion coating with either gelatin or collagen. Three groups of scaffolds were created and compared for both mechanical and biological properties. Surface modification with collagen or gelatin improved the hydrophilicity, water uptake and mechanical strength of the pristine scaffold. From microscopic observations and biochemical analysis, collagen-modified scaffold was the best for cartilage tissue engineering in terms of cell proliferation and extracellular matrix production. Chondrocytes/collagen-modified scaffold constructs were implanted subdermally in the dorsal spaces of female nude mice. Histological and immunohistochemical staining of the retrieved implants after 8 weeks revealed enhanced cartilage tissue formation. We conclude that collagen surface modification through immersion coating on SLS-manufactured scaffolds is a feasible scaffold for cartilage tissue engineering in craniofacial reconstruction. - Highlights: • Selective laser sintered polycaprolactone scaffolds are prepared. • Scaffolds are surface modified through immersion coating with gelatin or collagen. • Collagen-scaffold is the best for cartilage tissue engineering in vitro. • Chondrocytes/collagen-scaffold reveals enhanced cartilage tissue formation in vivo.

  19. Multimodal evaluation of tissue-engineered cartilage

    OpenAIRE

    Mansour, Joseph M.; Welter, Jean F.

    2013-01-01

    Tissue engineering (TE) has promise as a biological solution and a disease modifying treatment for arthritis. Although cartilage can be generated by TE, substantial inter- and intra-donor variability makes it impossible to guarantee optimal, reproducible results. TE cartilage must be able to perform the functions of native tissue, thus mechanical and biological properties approaching those of native cartilage are likely a pre-requisite for successful implantation. A quality-control assessment...

  20. Full-thickness cartilage lesion do not affect knee function in patients with ACL injury

    OpenAIRE

    2011-01-01

    Full-thickness cartilage lesion do not affect knee function in patients with ACL injury Abstract There is debate in the literature regarding the impact of full-thickness cartilage lesion on knee function in patients with ACL injury. The hypothesis of this study is that a full-thickness cartilage lesion at the time of ACL reconstruction does not influence knee function as measured by the Knee injury and Osteoarthritis Outcome Score (KOOS) in patients with ACL injury. Of the 4,849 prim...

  1. Advances in treatment of articular cartilage injuries

    Directory of Open Access Journals (Sweden)

    Yuan-cheng LI

    2013-05-01

    Full Text Available Cartilage is a kind of terminally differentiated tissue devoid of vessel or nerve, and it is difficult to repair by itself after damage. Many studies for the treatment of cartilage injuries were performed in recent years aiming at repair of the structure and restoration of its function for injured joint. This article reviews the traditional methods of treatment for cartilage injuries, such as joint lavage with the aid of arthroscope, abrasion chondroplasty, laser abrasion and chondroplasty, and drilling of the subchondral bone-marrow space. The research advances in treatment of articular cartilage injuries with tissue engineering were summarized.

  2. Multimodal evaluation of tissue-engineered cartilage.

    Science.gov (United States)

    Mansour, Joseph M; Welter, Jean F

    2013-02-01

    Tissue engineering (TE) has promise as a biological solution and a disease modifying treatment for arthritis. Although cartilage can be generated by TE, substantial inter- and intra-donor variability makes it impossible to guarantee optimal, reproducible results. TE cartilage must be able to perform the functions of native tissue, thus mechanical and biological properties approaching those of native cartilage are likely a pre-requisite for successful implantation. A quality-control assessment of these properties should be part of the implantation release criteria for TE cartilage. Release criteria should certify that selected tissue properties have reached certain target ranges, and should be predictive of the likelihood of success of an implant in vivo. Unfortunately, it is not currently known which properties are needed to establish release criteria, nor how close one has to be to the properties of native cartilage to achieve success. Achieving properties approaching those of native cartilage requires a clear understanding of the target properties and reproducible assessment methodology. Here, we review several main aspects of quality control as it applies to TE cartilage. This includes a look at known mechanical and biological properties of native cartilage, which should be the target in engineered tissues. We also present an overview of the state of the art of tissue assessment, focusing on native articular and TE cartilage. Finally, we review the arguments for developing and validating non-destructive testing methods for assessing TE products. PMID:23606823

  3. Preserved irradiated homolgous cartilage for orbital reconstruction.

    Science.gov (United States)

    Linberg, J V; Anderson, R L; Edwards, J J; Panje, W R; Bardach, J

    1980-07-01

    Human costal cartilage is an excellent implant material for orbital and periorbital reconstruction because of its light weight, strength, homogeneous consistency and the ease with which it can be carved. Its use has been limited by the necessity of a separate surgical procedure to obtain the material. Preserved irradiated homologous cartilage has been shown to have almost all the autogenous cartilage and is concenient to use. Preserved irradiated homologous cartilage transplants do not elicit rejection reactions, resist infection and rarely undergo absorption. PMID:7393528

  4. Electrostatic and Non-Electrostatic Contributions of Proteoglycans to the Compressive Equilibrium Modulus of Bovine Articular Cartilage

    OpenAIRE

    Guterl, Clare Canal; Hung, Clark T.; Ateshian, Gerard A.

    2010-01-01

    This study presents direct experimental evidence for assessing the electrostatic and nonelectrostatic contributions of proteoglycans to the compressive equilibrium modulus of bovine articular cartilage. Immature and mature bovine cartilage samples were tested in unconfined compression and their depth-dependent equilibrium compressive modulus was determined using strain measurements with digital image correlation analysis. The electrostatic contribution was assessed by testing samples in isoto...

  5. A spectroscopic approach to imaging and quantification of cartilage lesions in human knee joints

    Science.gov (United States)

    Johansson, A.; Sundqvist, T.; Kuiper, J.-H.; Öberg, P. Å.

    2011-03-01

    We have previously described a technology based on diffuse reflectance of broadband light for measuring joint articular cartilage thickness, utilizing that optical absorption is different in cartilage and subchondral bone. This study is the first evaluation of the technology in human material. We also investigated the prospects of cartilage lesion imaging, with the specific aim of arthroscopic integration. Cartilage thickness was studied ex vivo in a number of sites (n = 87) on human knee joint condyles, removed from nine patients during total knee replacement surgery. A reflectance spectrum was taken at each site and the cartilage thickness was estimated using the blue, green, red and near-infrared regions of the spectrum, respectively. Estimated values were compared with reference cartilage thickness values (taken after sample slicing) using an exponential model. Two-dimensional Monte Carlo simulations were performed in a theoretical analysis of the experimental results. The reference cartilage thickness of the investigated sites was 1.60 ± 1.30 mm (mean ± SD) in the range 0-4.2 mm. Highest correlation coefficients were seen for the calculations based on the near-infrared region after normalization to the red region (r = 0.86) and for the green region (r = 0.80).

  6. 76 FR 23609 - New Proposed Collection; Comment Request; Biospecimen and Physical Measures Formative Research...

    Science.gov (United States)

    2011-04-27

    ... questionnaires, storage and information management processes, and assay procedures, thereby informing data... formative research activities relating to the collection, storage, management, and assay of biospecimen and... Physical Measures Formative Research Methodology Studies for the National Children's Study SUMMARY:...

  7. Development of cartilage conduction hearing aid

    Directory of Open Access Journals (Sweden)

    H. Hosoi

    2010-04-01

    Full Text Available Purpose: The potential demand for hearing aids is increasing in accordance with aging of populations in many developed countries. Because certain patients cannot use air conduction hearing aids, they usually use bone conduction hearing aids. However, bone does not transmit sound as efficiently as air, and bone conduction hearing aids require surgery (bone anchored hearing aid or great pressure to the skull. The first purpose of this study is to examine the efficacy of a new sound conduction pathway via the cartilage. The second purpose is to develop a hearing aid with a cartilage conduction transducer for patients who cannot use regular air conduction hearing aids.Design/methodology/approach: We examined the hearing ability of a patient with atresia of both external auditory meatuses via three kinds of conduction pathways (air, bone, and cartilage. After the best position for the cartilage conduction transducer was found, audiometric evaluation was performed for his left ear with an insertion earphone (air conduction, a bone conduction transducer, and a cartilage conduction transducer. Then we made a new hearing aid using cartilage conduction and got subjective data from the patients.Findings: The tragal cartilage was the best position for the cartilage conduction transducer. The patient’s mean hearing levels were 58.3 dBHL, 6.7 dBHL, and 3.3 dBHL for air conduction, bone conduction, and cartilage conduction respectively. The hearing ability of the patients obtained from the cartilage conduction hearing aid was comparable to those from the bone conduction hearing aid.Practical implications: Hearing levels using cartilage conduction are very similar to those via bone conduction. Cartilage conduction hearing aids may overcome the practical disadvantages of bone conduction hearing aids such as pain and the need for surgery.Originality/value: We have clarified the efficacy of the cartilage conduction pathway and developed a prototype ‘cartilage

  8. Lessons from rare diseases of cartilage and bone.

    Science.gov (United States)

    Gallagher, James A; Ranganath, Lakshminarayan R; Boyde, Alan

    2015-06-01

    Studying severe phenotypes of rare syndromes can elucidate disease mechanisms of more common disorders and identify potential therapeutic targets. Lessons from rare bone diseases contributed to the development of the most successful class of bone active agents, the bisphosphonates. More recent research on rare bone diseases has helped elucidate key pathways and identify new targets in bone resorption and bone formation including cathepsin K and sclerostin, for which drugs are now in clinical trials. By contrast, there has been much less focus on rare cartilage diseases and osteoarthritis (OA) remains a common disease with no effective therapy. Investigation of rare cartilage syndromes is identifying new potential targets in OA including GDF5 and lubricin. Research on the arthropathy of the ultra-rare disease alkaptonuria has identified several new features of the OA phenotype, including high density mineralized protrusions (HDMPs) which constitute a newly identified mechanism of joint destruction.

  9. MR-based water content estimation in cartilage: design and validation of a method

    DEFF Research Database (Denmark)

    Shiguetomi Medina, Juan Manuel; Kristiansen, Maja Sophie; Ringgaard, Steffen;

    Purpose: Design and validation of an MR-based method that allows the calculation of the water content in cartilage tissue. Methods and Materials: Cartilage tissue T1 map based water content MR sequences were used on a 37 Celsius degree stable system. The T1 map intensity signal was analyzed on 6...... cartilage samples from living animals (pig) and on 8 gelatin samples which water content was already known. For the data analysis a T1 intensity signal map software analyzer used. Finally, the method was validated after measuring and comparing 3 more cartilage samples in a living animal (pig). The obtained...... data was analyzed and the water content calculated. Then, the same samples were freeze-dried (this technique allows to take out all the water that a tissue contains) and we measured the water they contained. Results:The 37 Celsius degree system and the analysis can be reproduced in a similar way. MR T1...

  10. MR-based Water Content Estimation in Cartilage: Design and Validation of a Method

    DEFF Research Database (Denmark)

    Shiguetomi Medina, Juan Manuel; Kristiansen, Maja Sofie; Ringgaard, Steffen;

    2012-01-01

    system (the closest to the body temperature) we measured, using the modified MR sequences, the T1 map intensity signal on 6 cartilage samples from living animals (pig) and on 8 gelatin samples which water content was already known. For the data analysis a T1 intensity signal map software analyzer was......Objective Design and validation of an MR-based method that allows the calculation of the water content in cartilage tissue. Material and Methods We modified and adapted to cartilage tissue T1 map based water content MR sequences commonly used in the neurology field. Using a 37 Celsius degree stable...... costumed and programmed. Finally, we validated the method after measuring and comparing 3 more cartilage samples in a living animal (pig). The obtained data was analyzed and the water content calculated. Then, the same samples were freeze-dried (this technique allows to take out all the water that a tissue...

  11. 耳屏软骨-软骨膜复合体厚度测量及其在鼓室成形术中的应用%The Measurements of the Thickness and Application of Tragus Cartilage -Perichondrium Complex in Tympanoplasty

    Institute of Scientific and Technical Information of China (English)

    杜娟; 许为青; 赵海专

    2014-01-01

    目的:测量耳屏软骨-软骨膜复合体厚度,探讨其对中耳炎手术治疗效果及重建听力的影响。方法49例(50耳)慢性中耳炎患者根据病情行伴或不伴乳突根治的鼓室成形术,均以耳屏软骨-软骨膜复合体修补鼓膜,术中测量耳屏软骨-软骨膜复合体厚度,术后每周随访一次至干耳,术后半年复查纯音听阈,分析耳屏软骨-软骨膜复合体厚度、干耳与否、干耳时间、鼓膜生长情况、术前和术后半年0.5、1.0、2.0、3.0kHz频率的纯音听阈。结果50耳耳屏软骨-软骨膜复合体的平均厚度为0.87±0.08mm(0.72~1.07mm),干耳时间3~12w ,中位数3 w ;42耳术后随访半年,鼓膜形态、色泽良好;其中31耳患耳气骨导差缩小,听力提高,另11耳听力结果未纳入分析。结论耳屏软骨-软骨膜复合体的厚度较恒定,作为修复中耳材料具有干耳时间较短、利于听力改善、并发症较少等特点。%Objective By measuring the thickness of tragus cartilage -perichondrium complex in 50 ears ,to evaluate the feasibility and efficacy of practical application with tragus cartilage -perichondrium complex in the tym-panoplasty based on a clinical tria1 .Methods A retrospective study was carried out among 50 ears with chronic oti-tis media ,treated in our hospital by a surgical procedure with tragus cartilage -perichondrium complex used in the tympanoplasty .The thickness of tragus cartilage -perichondrium complex was mearured during operation .Postoper-ative following -up was completed once a week to ear -drying .The pure tone audiometry(PTA) was reexamined at half a year after operation .The observations included the thickness of tragus cartilage -perichondrium comple ,the dry status ,drying time of tympanic membrane ,and the preoperative and half a year postoperative PT A .Results The average thickness of tragus cartilage-perichondrium complex in the 50 ears was 0 .87

  12. Noncontact evaluation of articular cartilage degeneration using a novel ultrasound water jet indentation system.

    Science.gov (United States)

    Lu, M-H; Zheng, Y P; Huang, Q-H; Ling, C; Wang, Q; Bridal, L; Qin, L; Mak, A

    2009-01-01

    We previously reported a noncontact ultrasound water jet indentation system for measuring and mapping tissue mechanical properties. The key idea was to utilize a water jet as an indenter as well as the coupling medium for high-frequency ultrasound. In this paper, the system was employed to assess articular cartilage degeneration, using stiffness ratio as an indicator of the mechanical properties of samples. Both the mechanical and acoustical properties of intact and degenerated bovine patellar articular cartilage (n = 8) were obtained in situ. It was found that the stiffness ratio was reduced by 44 +/- 17% after the articular cartilage was treated by 0.25% trypsin at 37 degrees C for 4 h while no significant difference in thickness was observed between the intact and degenerated samples. A significant decrease of 36 +/- 20% in the peak-to-peak amplitude of ultrasound echoes reflected from the cartilage surface was also found for the cartilage samples treated by trypsin. The results also showed that the stiffness obtained with the new method highly correlated with that measured using a standard mechanical testing protocol. A good reproducibility of the measurements was demonstrated. The present results showed that the ultrasound water jet indentation system may provide a potential tool for the non-destructive evaluation of articular cartilage degeneration by simultaneously obtaining mechanical properties, acoustical properties, and thickness data. PMID:19011965

  13. Effects of exercises on knee cartilage volume in young healthy adults: a randomized controlled trial

    Institute of Scientific and Technical Information of China (English)

    Lu Liangyu; Wang Yubin

    2014-01-01

    Background Acute effects of physical exercise on the deformational behavior of knee articular cartilage and changes in cartilage volume are definite.However,conclusive effects of different exercises on the loss of articular cartilage volume have not been proved.In this parallel-group randomized controlled trial,we tested whether 12 weeks of swimming,powerstriding,cycling,and running exercises would decrease the cartilage volume significantly and whether there would be a difference in the loss of cartilage volume after different types of exercises.Methods From October 2012 to January 2013 we evaluated 120 healthy volunteer students in Biomechanics Laboratory of Tongji University.Body mass index (BMI),right lower limb strength,and right knee cartilage magnetic resonance imaging (MRI) were obtained before exercise.MRI were conducted in East Hospital.The study was approved by Tongji University Ethical Committee,all subjects were randomly assigned to the running,powerstriding,cycling,swimming,and control groups by a drawing of lots.Each group contained 24 samples.At the end of 12 weeks of regular exercises,the same measurement procedures were applied.Cartilage volume was calculated with OSIRIS software based on the quantitative-MRI.Pre-and post-exercise comparisons were carried out using paired t-tests and one-way analysis of variance (ANOVA) was used to compare differences of cartilage volume loss between groups with Student-Newman-Keuls procedure for multiple comparisons.Results Running,cycling,and swimming groups resulted in a significant decrease in BMI.The quadriceps peak torque increased significantly in the swimming and cycling groups.Total cartilage volume significantly decreased in the running and cycling groups after 12 weeks of training,without any significant change in the nonimpact swimming,low-impact powerstriding,and control groups.Loss of total cartilage volume in the running and cycling groups were 2.21% (3.03) and 1.50% (0.42).Conclusions Twelve

  14. Measurement of He{sup 3} Formation in Pd

    Energy Technology Data Exchange (ETDEWEB)

    Tuggle, D.G.; Schwarz, R.B.; Maggiore, C.J.; Neal, M.A.; Whitcomb, M.A.; Bach, H.T.; Vourinen, J.E.

    1999-07-12

    This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Single crystal palladium samples were both grown at Los Alamos and purchased from a commercial source. These samples were aligned using X-ray diffraction and cut along appropriate crystal planes. After cutting, the samples were mechanically polished and then electro-etched to remove surface damage produced by the cutting and polishing. Ion beam channeling measurements and resonant ultrasound spectroscopy (RUS) measurements were completed on palladium and palladium deuteride samples. The ion beam channeling measurements on palladium samples confirmed the crystal structure and orientation of the samples and the measurements on palladium deuteride samples confirmed the octahedral location of the deuterium atoms in the palladium lattice. RUS measurements of the elastic constants of palladium and palladium deuteride samples were compared to previous measurements. Finally, RUS measurements were also completed on a palladium tritide sample at room temperature.

  15. Development of Atomic Force Microscope for Arthroscopic Knee Cartilage Inspection

    Science.gov (United States)

    Imer, Raphaël; Akiyama, Terunobu; de Rooij, Nicolaas F.; Stolz, Martin; Aebi, Ueli; Friederich, Niklaus F.; Koenig, Uwe; Wirz, Dieter; Daniels, A. U.; Staufer, Urs

    2006-03-01

    A recent study, based on ex vivo unconfined compression testing of normal, diseased, and enzymatically altered cartilage, revealed that a scanning force microscope (SFM), used as a nano-intender, is sensitive enough to enable measurement of alterations in the biomechanical properties of cartilage. Based on these ex vivo measurements, we have designed a quantitative diagnosis tool, the scanning force arthroscope (SFA), able to perform in vivo measurements during a standard arthroscopic procedure. For stabilizing and positioning the instrument relative to the surface under investigation, a pneumatic system has been developed. A segmented piezoelectric tube was used to perform the indentation displacement, and a pyramidal nanometer-scale silicon tip mounted on a cantilever with an integrated deflection sensor measured the biomechanical properties of cartilage. Mechanical means were designed to protect the fragile cantilever during the insertion of the instrument into the knee joint. The stability of the pneumatic stage was checked with a prototype SFA. In a series of tests, load-displacement curves were recorded in a knee phantom and, more recently, in a pig’s leg.

  16. Quantitative characterization of articular cartilage using Mueller matrix imaging and multiphoton microscopy

    Science.gov (United States)

    Ellingsen, Pa˚L. Gunnar; Lilledahl, Magnus Borstad; Aas, Lars Martin Sandvik; Davies, Catharina De Lange; Kildemo, Morten

    2011-11-01

    The collagen meshwork in articular cartilage of chicken knee is characterized using Mueller matrix imaging and multiphoton microscopy. Direction and degree of dispersion of the collagen fibers in the superficial layer are found using a Fourier transform image-analysis technique of the second-harmonic generated image. Mueller matrix images are used to acquire structural data from the intermediate layer of articular cartilage where the collagen fibers are too small to be resolved by optical microscopy, providing a powerful multimodal measurement technique. Furthermore, we show that Mueller matrix imaging provides more information about the tissue compared to standard polarization microscopy. The combination of these techniques can find use in improved diagnosis of diseases in articular cartilage, improved histopathology, and additional information for accurate biomechanical modeling of cartilage.

  17. Prolactin promotes cartilage survival and attenuates inflammation in inflammatory arthritis

    Science.gov (United States)

    Adán, Norma; Guzmán-Morales, Jessica; Ledesma-Colunga, Maria G.; Perales-Canales, Sonia I.; Quintanar-Stéphano, Andrés; López-Barrera, Fernando; Méndez, Isabel; Moreno-Carranza, Bibiana; Triebel, Jakob; Binart, Nadine; Martínez de la Escalera, Gonzalo; Thebault, Stéphanie; Clapp, Carmen

    2013-01-01

    Chondrocytes are the only cells in cartilage, and their death by apoptosis contributes to cartilage loss in inflammatory joint diseases, such as rheumatoid arthritis (RA). A putative therapeutic intervention for RA is the inhibition of apoptosis-mediated cartilage degradation. The hormone prolactin (PRL) frequently increases in the circulation of patients with RA, but the role of hyperprolactinemia in disease activity is unclear. Here, we demonstrate that PRL inhibits the apoptosis of cultured chondrocytes in response to a mixture of proinflammatory cytokines (TNF-α, IL-1β, and IFN-γ) by preventing the induction of p53 and decreasing the BAX/BCL-2 ratio through a NO-independent, JAK2/STAT3–dependent pathway. Local treatment with PRL or increasing PRL circulating levels also prevented chondrocyte apoptosis evoked by injecting cytokines into the knee joints of rats, whereas the proapoptotic effect of cytokines was enhanced in PRL receptor–null (Prlr–/–) mice. Moreover, eliciting hyperprolactinemia in rats before or after inducing the adjuvant model of inflammatory arthritis reduced chondrocyte apoptosis, proinflammatory cytokine expression, pannus formation, bone erosion, joint swelling, and pain. These results reveal the protective effect of PRL against inflammation-induced chondrocyte apoptosis and the therapeutic potential of hyperprolactinemia to reduce permanent joint damage and inflammation in RA. PMID:23908112

  18. Arthroscopic optical coherence tomography provides detailed information on articular cartilage lesions in horses.

    Science.gov (United States)

    te Moller, N C R; Brommer, H; Liukkonen, J; Virén, T; Timonen, M; Puhakka, P H; Jurvelin, J S; van Weeren, P R; Töyräs, J

    2013-09-01

    Arthroscopy enables direct inspection of the articular surface, but provides no information on deeper cartilage layers. Optical coherence tomography (OCT), based on measurement of reflection and backscattering of light, is a diagnostic technique used in cardiovascular surgery and ophthalmology. It provides cross-sectional images at resolutions comparable to that of low-power microscopy. The aim of this study was to determine if OCT is feasible for advanced clinical assessment of lesions in equine articular cartilage during diagnostic arthroscopy. Diagnostic arthroscopy of 36 metacarpophalangeal joints was carried out ex vivo. Of these, 18 joints with varying degrees of cartilage damage were selected, wherein OCT arthroscopy was conducted using an OCT catheter (diameter 0.9 mm) inserted through standard instrument portals. Five sites of interest, occasionally supplemented with other locations where defects were encountered, were arthroscopically graded according to the International Cartilage Repair Society (ICRS) classification system. The same sites were evaluated qualitatively (ICRS classification and morphological description of the lesions) and quantitatively (measurement of cartilage thickness) on OCT images. OCT provided high resolution images of cartilage enabling determination of cartilage thickness. Comparing ICRS grades determined by both arthroscopy and OCT revealed poor agreement. Furthermore, OCT visualised a spectrum of lesions, including cavitation, fibrillation, superficial and deep clefts, erosion, ulceration and fragmentation. In addition, with OCT the arthroscopically inaccessible area between the dorsal MC3 and P1 was reachable in some cases. Arthroscopically-guided OCT provided more detailed and quantitative information on the morphology of articular cartilage lesions than conventional arthroscopy. OCT could therefore improve the diagnostic value of arthroscopy in equine orthopaedic surgery. PMID:23810744

  19. Comparative study of MR 3D-SPACE,3D-True FISP sequences at measuring defect area in articular cartilage of knee%3D-SPACE、3D-True FISP序列测量膝关节软骨缺损面积的比较研究

    Institute of Scientific and Technical Information of China (English)

    陈浩; 孙岩; 秦卫; 胡丹; 郝跃峰; 刘可夫; 庄启湘; 郑志勇

    2016-01-01

    Objective:To assess the accuracy of defect area in articular cartilage of knee by comparing results from the 3D-SPACE sequence and the 3D-True FISP sequence. Methods:A 1.5 T MRI system was used to perform a study of 38 pa-tients,and lesion visualization of articular cartilage of knee joint was compared. Measurement results of defect area in articular cartilage of knee (52 lesions) by 3D-SPACE sequence and 3D-True FISP sequence was compared with the measurement re-sults by arthroscopy. Results:The average size of defective articular cartilage of knee joint in 3D-SPACE sequence was (2.337±0.868)cm2,and in 3D-True FISP sequence was (1.423±0.560)cm2. 3D-SPACE sequence were significantly higher than with the 3D-True FISP sequence (P<0.05) in visualization of articular cartilage of knee joint,also in assessing the accuracy of defect area. Conclusion:For the depiction of articular cartilage of knee,the 3D-SPACE sequence is superior to the 3D-CISS se-quence,also in assessing the accuracy of defect area in articular cartilage of knee.%目的:比较三维可变翻转角快速自旋回波序列(3-dimensional sampling perfection with application optimized contrast using different flip angle evolutions,3D-SPACE)、三维真稳态进动快速成像序列(3D-true fast imaging with steady-state precession,3D-True FISP)测量膝关节软骨缺损面积的准确性。方法:选取38例膝关节软骨缺损患者,在1.5 T MRI仪上对比3D-SPACE、3D-True FISP序列对膝关节软骨的显示质量,并将2组序列测量的缺损软骨面积(52处)与关节镜测量结果进行比较。结果:3D-SPACE、3D-True FISP序列测量的膝软骨缺损面积平均每膝分别为(2.337±0.868)cm2、(1.423±0.560)cm2。3D-SPACE序列比3D-True FISP序列在对膝关节软骨显示质量上更优(P<0.05),且对软骨缺损面积的显示更准确(P<0.05)。结论:3D-SPACE序列比3D-True FISP序列能更好地显示膝关节软骨,对膝关节

  20. Cartilage surface characterization by frictional dissipated energy during axially loaded knee flexion--an in vitro sheep model.

    Science.gov (United States)

    Lorenz, Andrea; Rothstock, Stephan; Bobrowitsch, Evgenij; Beck, Alexander; Gruhler, Gerhard; Ipach, Ingmar; Leichtle, Ulf G; Wülker, Nikolaus; Walter, Christian

    2013-05-31

    Cartilage defects and osteoarthritis (OA) have an increasing incidence in the aging population. A wide range of treatment options are available. The introduction of each new treatment requires controlled, evidence based, histological and biomechanical studies to identify potential benefits. Especially for the biomechanical testing there is a lack of established methods which combine a physiologic testing environment of complete joints with the possibility of body-weight simulation. The current in-vitro study presents a new method for the measurement of friction properties of cartilage on cartilage in its individual joint environment including the synovial fluid. Seven sheep knee joints were cyclically flexed and extended under constant axial load with intact joint capsule using a 6° of freedom robotic system. During the cyclic motion, the flexion angle and the respective torque were recorded and the dissipated energy was calculated. Different mechanically induced cartilage defect sizes (16 mm², 50 mm², 200 mm²) were examined and compared to the intact situation at varying levels of the axial load. The introduced setup could significantly distinguish between most of the defect sizes for all load levels above 200 N. For these higher load levels, a high reproducibility was achieved (coefficient of variation between 4% and 17%). The proposed method simulates a natural environment for the analysis of cartilage on cartilage friction properties and is able to differentiate between different cartilage defect sizes. Therefore, it is considered as an innovative method for the testing of new treatment options for cartilage defects.

  1. Deformation of articular cartilage during static loading of a knee joint--experimental and finite element analysis.

    Science.gov (United States)

    Halonen, K S; Mononen, M E; Jurvelin, J S; Töyräs, J; Salo, J; Korhonen, R K

    2014-07-18

    Novel conical beam CT-scanners offer high resolution imaging of knee structures with i.a. contrast media, even under weight bearing. With this new technology, we aimed to determine cartilage strains and meniscal movement in a human knee at 0, 1, 5, and 30 min of standing and compare them to the subject-specific 3D finite element (FE) model. The FE model of the volunteer׳s knee, based on the geometry obtained from magnetic resonance images, was created to simulate the creep. The effects of collagen fibril network stiffness, nonfibrillar matrix modulus, permeability and fluid flow boundary conditions on the creep response in cartilage were investigated. In the experiment, 80% of the maximum strain in cartilage developed immediately, after which the cartilage continued to deform slowly until the 30 min time point. Cartilage strains and meniscus movement obtained from the FE model matched adequately with the experimentally measured values. Reducing the fibril network stiffness increased the mean strains substantially, while the creep rate was primarily influenced by an increase in the nonfibrillar matrix modulus. Changing the initial permeability and preventing fluid flow through noncontacting surfaces had a negligible effect on cartilage strains. The present results improve understanding of the mechanisms controlling articular cartilage strains and meniscal movements in a knee joint under physiological static loading. Ultimately a validated model could be used as a noninvasive diagnostic tool to locate cartilage areas at risk for degeneration.

  2. Regulatory Challenges for Cartilage Repair Technologies.

    Science.gov (United States)

    McGowan, Kevin B; Stiegman, Glenn

    2013-01-01

    In the United States, few Food and Drug Administration (FDA)-approved options exist for the treatment of focal cartilage and osteochondral lesions. Developers of products for cartilage repair face many challenges to obtain marketing approval from the FDA. The objective of this review is to discuss the necessary steps for FDA application and approval for a new cartilage repair product. FDA Guidance Documents, FDA Panel Meetings, scientific organization recommendations, and clinicaltrials.gov were reviewed to demonstrate the current thinking of FDA and the scientific community on the regulatory process for cartilage repair therapies. Cartilage repair therapies can receive market approval from FDA as medical devices, drugs, or biologics, and the specific classification of product can affect the nonclinical, clinical, and regulatory strategy to bring the product to market. Recent FDA guidance gives an outline of the required elements to bring a cartilage repair product to market, although these standards are often very general. As a result, companies have to carefully craft their study patient population, comparator group, and clinical endpoint to best showcase their product's attributes. In addition, regulatory strategy and manufacturing process validation need to be considered early in the clinical study process to allow for timely product approval following the completion of clinical study. Although the path to regulatory approval for a cartilage repair therapy is challenging and time-consuming, proper clinical trial planning and attention to the details can eventually save companies time and money by bringing a product to the market in the most expeditious process possible.

  3. Cartilage collagen damage in hip osteoarthritis similar to that seen in knee osteoarthritis; a case–control study of relationship between collagen, glycosaminoglycan and cartilage swelling

    Directory of Open Access Journals (Sweden)

    Hosseininia Shahrzad

    2013-01-01

    Full Text Available Abstract Background It remains to be shown whether OA shares molecular similarities between different joints in humans. This study provides evidence for similarities in cartilage molecular damage in osteoarthritic (OA joints. Methods Articular cartilage from osteoarthritic hip joints were analysed and compared to non-OA controls regarding collagen, glycosaminoglycan and water content. Femoral heads from 16 osteoarthritic (OA and 20 reference patients were obtained from hip replacement surgery due to OA and femoral neck fracture, respectively. Cartilage histological changes were assessed by Mankin grading and denatured collagen type II immunostaining and cartilage was extracted by α-chymotrypsin. Hydroxyproline and Alcian blue binding assays were used to measure collagen and glycosaminoglycan (GAG content, respectively. Results Mankin and immunohistology scores were significantly higher in hip OA samples than in reference samples. Cartilage water content was 6% higher in OA samples than in references. 2.5 times more collagen was extracted from OA than from reference samples. There was a positive association between water content and percentage of extractable collagen pool (ECP in both groups. The amounts of collagen per wet and dry weights did not differ statistically between OA and reference cartilage. % Extractable collagen was not related to collagen per dry weight in either group. However when collagen was expressed by wet weight there was a negative correlation between % extractable and collagen in OA cartilage. The amount of GAG per wet weight was similar in both groups but the amount of GAG per dry weight was higher in OA samples compared to reference samples, which suggests a capacity for GAG biosynthesis in hip OA cartilage. Neither of the studied parameters was related to age in either group. Conclusions Increased collagen extractability and water content in human hip cartilage is associated with OA pathology and can be observed at

  4. Structural Measures for Controlling Avalanches in Formation Zone

    Directory of Open Access Journals (Sweden)

    Vinay Chaudhary

    2006-11-01

    Full Text Available Jammu-Srinagar national highway (NH-1A, a lifeline of the Kashmir valley, gains considerableimportance as being the only link between the Kashmir valley and the rest of the country. Astretch of 15 km is marred by 15 major avalanche sites, out of that D-10 avalanche site takes aheavy toll of life and property, besides bringing the busiest highway to a standstill for daystogether, year after year. Therefore, this avalanche site was selected for installation of avalanchecontrolstructures in formation zone and demonstration of technology thereof. A combinationof wind-control structures, supporting structures, and controlled release of avalanches usingexplosive, has been adopted to mitigate avalanche hazard. As a result, the D-10 site can boastof having become a school for live demonstration of the avalanche-control methods on themighty Pir Panjal range at more than 3200 m above the sea level. This paper deals with themethods used for control of avalanches in formation zone of D-10 avalanche site and brings outtheir effectiveness and site-specific applications.

  5. An integrin-dependent role of pouch endoderm in hyoid cartilage development.

    Directory of Open Access Journals (Sweden)

    Justin Gage Crump

    2004-09-01

    Full Text Available Pharyngeal endoderm is essential for and can reprogram development of the head skeleton. Here we investigate the roles of specific endodermal structures in regulating craniofacial development. We have isolated an integrinalpha5 mutant in zebrafish that has region-specific losses of facial cartilages derived from hyoid neural crest cells. In addition, the cranial muscles that normally attach to the affected cartilage region and their associated nerve are secondarily reduced in integrinalpha5- animals. Earlier in development, integrinalpha5 mutants also have specific defects in the formation of the first pouch, an outpocketing of the pharyngeal endoderm. By fate mapping, we show that the cartilage regions that are lost in integrinalpha5 mutants develop from neural crest cells directly adjacent to the first pouch in wild-type animals. Furthermore, we demonstrate that Integrinalpha5 functions in the endoderm to control pouch formation and cartilage development. Time-lapse recordings suggest that the first pouch promotes region-specific cartilage development by regulating the local compaction and survival of skeletogenic neural crest cells. Thus, our results reveal a hierarchy of tissue interactions, at the top of which is the first endodermal pouch, which locally coordinates the development of multiple tissues in a specific region of the vertebrate face. Lastly, we discuss the implications of a mosaic assembly of the facial skeleton for the evolution of ray-finned fish.

  6. T2 mapping of articular cartilage of the glenohumeral joint at 3.0 T in healthy volunteers: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yusuhn [Seoul National University Bundang Hospital, Department of Radiology, Seongnam-si, Gyeonggi-do (Korea, Republic of); Choi, Jung-Ah [Seoul National University Bundang Hospital, Department of Radiology, Seongnam-si, Gyeonggi-do (Korea, Republic of); Hallym University Dongtan Sacred Heart Hospital, Department of Radiology, Hwaseong, Gyeonggi-do (Korea, Republic of)

    2016-07-15

    The purpose of this study was to assess the T2 values of the glenohumeral joint cartilage in healthy asymptomatic individuals at 3.0 T and to analyze the T2 profile of the humeral cartilage. This prospective study was approved by our institutional review board and written informed consent was obtained. Thirteen subjects (mean age, 28.6 years; age range, 24-33 years) were included and underwent multiecho spin-echo T2-weighted MR imaging and T2 mapping was acquired. Regions of interest were placed on the humeral cartilage and glenoid cartilage on oblique coronal images. T2 profiles of humeral cartilage were measured from the bone-cartilage interface to the articular surface. Intra-observer agreement was analyzed using intraclass correlation coefficient (ICC). All 13 joints showed normal appearance on conventional T2-weighted images. The mean T2 values of humeral and glenoid cartilage were 50.5 ± 12.1 and 49.0 ± 9.9 ms, respectively. Intra-observer agreement was good, as determined by ICC (0.736). Longer T2 values were observed at the articular surface with a tendency to decrease toward the bone-cartilage interface. The mean cartilage T2 value was 69.03 ± 21.2 ms at the articular surface and 46.99 ± 19.6 ms at the bone-cartilage interface. T2 values of the glenohumeral joint cartilage were similar to reported values of cartilage in the knee. The T2 profile of normal humeral cartilage showed a spatial variation with an increase in T2 values from the subchondral bone to the articular surface. (orig.)

  7. [Surgical therapeutic possibilities of cartilage damage].

    Science.gov (United States)

    Burkart, A C; Schoettle, P B; Imhoff, A B

    2001-09-01

    Therapy of cartilage damage is a frequent problem, especially in the young and active patient. For the treatment of a cartilage damage we have to consider the size of the defect, age and weight of the patient, meniscal tears, ligament instabilities and varus-/valgus-malalignment. Lavage, shaving and debridement are only sufficient for a short time and have no long term effect. Abrasio and drilling could be useful in eldery people. Microfracturing seems to be an effective alternative for small defects. The restoration of the cartilage surface with the use of autologous chondrocyte transplantation, osteochondral autograft transplantation and posterior condyle transfer seems to be an adequate treatment for younger patients. PMID:11572120

  8. Semiquantitative correction of posttraumatic enophthalmos with sliced cartilage grafts.

    Science.gov (United States)

    Matsuo, K; Hirose, T; Furuta, S; Hayashi, M; Watanabe, T

    1989-03-01

    A simple surgical technique for correcting posttraumatic enophthalmos is described. The steps are as follows: (1) a plaster mold is obtained of the patient's face, (2) wax is added to the enophthalmic eye of the plaster mold until it becomes symmetrical, (3) the quantity of wax is measured, and (4) the same amount of sliced costal cartilage is implanted beneath the periosteum of the extended orbital wall behind the vertical axis of the globe. Using this technique, we have successfully treated six patients with traumatic orbital floor defects without complication. This approach is useful for decreasing the orbital volume using a semiquantitative procedure to estimate the amount of graft material required. In this respect, costal cartilage demonstrates a marked advantage, with stability and cosmetic appearance verified over 12 months of follow-up.

  9. Semiquantitative correction of posttraumatic enophthalmos with sliced cartilage grafts.

    Science.gov (United States)

    Matsuo, K; Hirose, T; Furuta, S; Hayashi, M; Watanabe, T

    1989-03-01

    A simple surgical technique for correcting posttraumatic enophthalmos is described. The steps are as follows: (1) a plaster mold is obtained of the patient's face, (2) wax is added to the enophthalmic eye of the plaster mold until it becomes symmetrical, (3) the quantity of wax is measured, and (4) the same amount of sliced costal cartilage is implanted beneath the periosteum of the extended orbital wall behind the vertical axis of the globe. Using this technique, we have successfully treated six patients with traumatic orbital floor defects without complication. This approach is useful for decreasing the orbital volume using a semiquantitative procedure to estimate the amount of graft material required. In this respect, costal cartilage demonstrates a marked advantage, with stability and cosmetic appearance verified over 12 months of follow-up. PMID:2919197

  10. Properties and Mechanobiological Behavior of Bovine Nasal Septum Cartilage.

    Science.gov (United States)

    Correro-Shahgaldian, Maria Rita; Introvigne, Jasmin; Ghayor, Chafik; Weber, Franz E; Gallo, Luigi M; Colombo, Vera

    2016-05-01

    Bovine nasal septum (BNS) is a source of non-load bearing hyaline cartilage. Little information is available on its mechanical and biological properties. The aim of this work was to assess the characteristics of BNS cartilage and investigate its behavior in in vitro mechanobiological experiments. Mechanical tests, biochemical assays, and microscopic assessment were performed for tissue characterization. Compressions tests showed that the tissue is viscoelastic, although values of elastic moduli differ from the ones of other cartilaginous tissues. Water content was 78 ± 1.4%; glycosaminoglycans and collagen contents-measured by spectrophotometric assay and hydroxyproline assay-were 39 ± 5% and 25 ± 2.5% of dry weight, respectively. Goldner's Trichrome staining and transmission electron microscopy proved isotropic cells distribution and results of earlier cell division. Furthermore, gene expression was measured after uniaxial compression, showing variations depending on compression time as well as trends depending on equilibration time. In conclusion, BNS has been characterized at several levels, revealing that bovine nasal tissue is regionally homogeneous. Results suggest that, under certain conditions, BNS could be used to perform in vitro cartilage loading experiments.

  11. Fourier transform infrared imaging of focal lesions in Human osteoarthritic cartilage

    Directory of Open Access Journals (Sweden)

    David-Vaudey E.

    2005-11-01

    Full Text Available Fourier Transform Infrared Imaging (FTIRI is a new method for quantitatively assessing the spatial-chemical composition of complex materials. This technique has been applied to examine the feasibility of measuring changes in the composition and distribution of collagen and proteoglycan macromolecules in human osteoarthritic cartilage. Human cartilage was acquired post-operatively from total joint replacement patients. Samples were taken at the site of a focal lesion, adjacent to the lesion, and from relatively healthy cartilage away from the lesion. Sections were prepared for FTIRI and histochemical grading. FTIRI spectral images were acquired for the superficial, intermediate, and deep layers for each sample. Euclidean distance mapping and quantitative partial least squares analysis (PLS were performed using reference spectra for type-II collagen and chondroitin 6-sulphate (CS6. FTIRI results were correlated to the histology-based Mankin scoring system. PLS analysis found relatively low relative concentrations of collagen (38 ± 10% and proteoglycan (22 ± 9% in osteoarthritic cartilage. Focal lesions were generally found to contain less CS6 compared to cartilage tissue adjacent to the lesion. Loss of proteoglycan content was well correlated to histological Mankin scores (r=0.69, p<0.0008. The evaluation of biological tissues with FTIRI can provide unique quantitative information on how disease can affect biochemical distribution and composition. This study has demonstrated that FTIRI is useful in quantitatively assessing pathology-related changes in the composition and distribution of primary macromolecular components of human osteoarthritic cartilage.

  12. Analysis of human knee osteoarthritic cartilage using polarization sensitive second harmonic generation microscopy

    Science.gov (United States)

    Kumar, Rajesh; Grønhaug, Kirsten M.; Romijn, Elisabeth I.; Drogset, Jon O.; Lilledahl, Magnus B.

    2014-05-01

    Osteoarthritis is one of the most prevalent joint diseases in the world. Although the cause of osteoarthritis is not exactly clear, the disease results in a degradation of the quality of the articular cartilage including collagen and other extracellular matrix components. We have investigated alterations in the structure of collagen fibers in the cartilage tissue of the human knee using mulitphoton microscopy. Due to inherent high nonlinear susceptibility, ordered collagen fibers present in the cartilage tissue matrix produces strong second harmonic generation (SHG) signals. Significant morphological differences are found in different Osteoarthritic grades of cartilage by SHG microscopy. Based on the polarization analysis of the SHG signal, we find that a few locations of hyaline cartilage (mainly type II collagen) is being replaced by fibrocartilage (mainly type I cartilage), in agreement with earlier literature. To locate the different types and quantify the alteration in the structure of collagen fiber, we employ polarization-SHG microscopic analysis, also referred to as _-tensor imaging. The image analysis of p-SHG image obtained by excitation polarization measurements would represent different tissue constituents with different numerical values at pixel level resolution.

  13. Investigating Organisational Innovativeness : Developing a Multidimensional Formative Measure

    NARCIS (Netherlands)

    Pallas, Florian; Böckermann, Florian; Goetz, Oliver; Tecklenburg, Kirstin

    2013-01-01

    To survive competition, it is vital for firms to be innovative. As a firm's cultural predisposition, organisational innovativeness provides an environment that fosters innovations and thus actively supports new product or service development. The purpose of this study is to measure organisational in

  14. Chemical Biology in the Embryo: In Situ Imaging of Sulfur Biochemistry in Normal and Proteoglycan-Deficient Cartilage Matrix.

    Science.gov (United States)

    Hackett, Mark J; George, Graham N; Pickering, Ingrid J; Eames, B Frank

    2016-05-01

    Proteoglycans (PGs) are heavily glycosylated proteins that play major structural and biological roles in many tissues. Proteoglycans are abundant in cartilage extracellular matrix; their loss is a main feature of the joint disease osteoarthritis. Proteoglycan function is regulated by sulfation-sulfate ester formation with specific sugar residues. Visualization of sulfation within cartilage matrix would yield vital insights into its biological roles. We present synchrotron-based X-ray fluorescence imaging of developing zebrafish cartilage, providing the first in situ maps of sulfate ester distribution. Levels of both sulfur and sulfate esters decrease as cartilage develops through late phase differentiation (maturation or hypertrophy), suggesting a functional link between cartilage matrix sulfur content and chondrocyte differentiation. Genetic experiments confirm that sulfate ester levels were due to cartilage proteoglycans and support the hypothesis that sulfate ester levels regulate chondrocyte differentiation. Surprisingly, in the PG synthesis mutant, the total level of sulfur was not significantly reduced, suggesting sulfur is distributed in an alternative chemical form during lowered cartilage proteoglycan production. Fourier transform infrared imaging indicated increased levels of protein in the mutant fish, suggesting that this alternative sulfur form might be ascribed to an increased level of protein synthesis in the mutant fish, as part of a compensatory mechanism.

  15. In vivo articular cartilage deformation: noninvasive quantification of intratissue strain during joint contact in the human knee

    Science.gov (United States)

    Chan, Deva D.; Cai, Luyao; Butz, Kent D.; Trippel, Stephen B.; Nauman, Eric A.; Neu, Corey P.

    2016-01-01

    The in vivo measurement of articular cartilage deformation is essential to understand how mechanical forces distribute throughout the healthy tissue and change over time in the pathologic joint. Displacements or strain may serve as a functional imaging biomarker for healthy, diseased, and repaired tissues, but unfortunately intratissue cartilage deformation in vivo is largely unknown. Here, we directly quantified for the first time deformation patterns through the thickness of tibiofemoral articular cartilage in healthy human volunteers. Magnetic resonance imaging acquisitions were synchronized with physiologically relevant compressive loading and used to visualize and measure regional displacement and strain of tibiofemoral articular cartilage in a sagittal plane. We found that compression (of 1/2 body weight) applied at the foot produced a sliding, rigid-body displacement at the tibiofemoral cartilage interface, that loading generated subject- and gender-specific and regionally complex patterns of intratissue strains, and that dominant cartilage strains (approaching 12%) were in shear. Maximum principle and shear strain measures in the tibia were correlated with body mass index. Our MRI-based approach may accelerate the development of regenerative therapies for diseased or damaged cartilage, which is currently limited by the lack of reliable in vivo methods for noninvasive assessment of functional changes following treatment.

  16. Preparation and characterization of polyvinyl alcohol hydrogels crosslinked by biodegradable polyurethane for tissue engineering of cartilage

    International Nuclear Information System (INIS)

    Polyurethane was prepared from hexamethylene diisocyanate (HMDI) and polycaprolactone diol (PCL) with stoichiometry ratio of two in a reactor to form prepolymer. Polyvinyl alcohol (PVA) at PVA/prepolymer ratios of 8, 4, 2 and 1 was crosslinked with the former degradable polyester polyurethane. Fourier transform infrared (FTIR) was employed to confirm polyurethane formation during the course of reactions. FTIR spectrum revealed bands at 1729-1733 cm-1 and 3347-3340 cm-1 which indicates carbonyl and NH of amine groups, respectively. Polyurethane formation was also confirmed by the absence of the isocyanate peaks (NCO) at 2270 cm-1. Dynamic mechanical thermal analysis (DMTA) showed that by increasing prepolymer concentration glass transition temperature decreases from 26 deg. C for PVA to 19 deg. C for sample with PVA/prepolymer ratio of 4 and then it rises up to 31 deg. C. Water uptake measurements illustrated about four fold reduction in swelling ratio of PVA after crosslinking and the sample with equal amounts of PVA and PPU had water uptake of 100%, close to that of a natural cartilage and much less than PVA (425%). All samples had compressive modulus in the range of the articular cartilage (1.9-14.4 MPa). The morphology of the isolated cells on the samples was evaluated by scanning electron microscopy (SEM) and revealed cell attachment and proliferation. The cell viability (3-4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, MTT) and GAG expression (dimethylmethylene blue, DMMB) assays with human chondrocytes on the sample with PVA/prepolymer ratio of one showed about 14 and 33% increase in cell viability and GAG expression after 14 days of culture compare to the PVA, respectively.

  17. Preparation and characterization of polyvinyl alcohol hydrogels crosslinked by biodegradable polyurethane for tissue engineering of cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Bonakdar, Shahin [Biomedical Engineering Department, Amirkabir University of Technology, Tehran, 15875-4413 (Iran, Islamic Republic of); Emami, Shahriar Hojjati, E-mail: shahriar16@yahoo.com [Biomedical Engineering Department, Amirkabir University of Technology, Tehran, 15875-4413 (Iran, Islamic Republic of); Shokrgozar, Mohammad Ali [National Cell Bank of Iran, Pasteur Institute of Iran, Tehran, 13164 (Iran, Islamic Republic of); Farhadi, Afshin [Tehran Azad University of Medical Science, Amiralmomenin Hospital (Iran, Islamic Republic of); Ahmadi, Seyed Amir Hoshiar [Biomedical Engineering Department, Amirkabir University of Technology, Tehran, 15875-4413 (Iran, Islamic Republic of); Amanzadeh, Amir [National Cell Bank of Iran, Pasteur Institute of Iran, Tehran, 13164 (Iran, Islamic Republic of)

    2010-05-10

    Polyurethane was prepared from hexamethylene diisocyanate (HMDI) and polycaprolactone diol (PCL) with stoichiometry ratio of two in a reactor to form prepolymer. Polyvinyl alcohol (PVA) at PVA/prepolymer ratios of 8, 4, 2 and 1 was crosslinked with the former degradable polyester polyurethane. Fourier transform infrared (FTIR) was employed to confirm polyurethane formation during the course of reactions. FTIR spectrum revealed bands at 1729-1733 cm{sup -1} and 3347-3340 cm{sup -1} which indicates carbonyl and NH of amine groups, respectively. Polyurethane formation was also confirmed by the absence of the isocyanate peaks (NCO) at 2270 cm{sup -1}. Dynamic mechanical thermal analysis (DMTA) showed that by increasing prepolymer concentration glass transition temperature decreases from 26 deg. C for PVA to 19 deg. C for sample with PVA/prepolymer ratio of 4 and then it rises up to 31 deg. C. Water uptake measurements illustrated about four fold reduction in swelling ratio of PVA after crosslinking and the sample with equal amounts of PVA and PPU had water uptake of 100%, close to that of a natural cartilage and much less than PVA (425%). All samples had compressive modulus in the range of the articular cartilage (1.9-14.4 MPa). The morphology of the isolated cells on the samples was evaluated by scanning electron microscopy (SEM) and revealed cell attachment and proliferation. The cell viability (3-4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, MTT) and GAG expression (dimethylmethylene blue, DMMB) assays with human chondrocytes on the sample with PVA/prepolymer ratio of one showed about 14 and 33% increase in cell viability and GAG expression after 14 days of culture compare to the PVA, respectively.

  18. Formation Mechanism of Chunky Graphite and Its Preventive Measures

    Institute of Scientific and Technical Information of China (English)

    Hideo Nakae; Sanghoon Jung; Ho-Chul Shin

    2008-01-01

    The formation mechanism of chunky graphite has been reviewed and studied. The study consisted of a unidirectional solidification method, a small droplet method and a furnace cooling method. Four kinds of iron samples were prepared, namely, the pure Fe-C, Fe-C-S, Fe-C-Ce and Fe-C-Si-Ce alloys, and three kinds of nickel samples, namely the Ni-C, Ni-C-S and Ni-C-Mg alloys. The results of the unidirectional solidification of the Ni-C alloys showed that spheroidal graphite is not observed in the continuous solidified region, in which only flake-like graphite is observed, while spheroidal graphite is usually observed in the quenched liquid region. The existence of spheroidal graphite in the solidified phase is recognized only in the discontinuous growth mode of the Ni-C-Mg alloy solidified at 150 mm/h. This means that the spheroidal graphite is directly crystallized from the melt and entrapped by the flake-like chunky graphite that is formed by the continuous growth mode. In the small droplet method, a small piece of the Fe-C or Fe-C-Ce sample was melted on a pure graphite plate then cooled at a different cooling rate in a He-3%H2 atmosphere. The graphite in the Fe-C-Ce alloy is usually spherical. Nevertheless, the graphite morphology of the final solidified area changed from spherical to chunky and chunky to ledeburite with an increase in the cooling rate. This means that the chunky graphite is formed in the residual liquid region by the solidification into Fe-graphite system. The sample was cooled in a furnace, and the graphite morphology changes from spherical to chunky and chunky to ledeburite with the decrease in the Si content. These phenomena can be confirmed by the cooling curves of these samples.

  19. The structure and function of cartilage proteoglycans

    Directory of Open Access Journals (Sweden)

    P J Roughley

    2006-11-01

    Full Text Available Cartilage contains a variety of proteoglycans that are essential for its normal function. These include aggrecan, decorin, biglycan, fibromodulin and lumican. Each proteoglycan serves several functions that are determined by both its core protein and its glycosaminoglycan chains. This review discusses the structure/function relationships of the cartilage proteoglycans, and the manner in which perturbations in proteoglycan structure or abundance can adversely affect tissue function.

  20. Materials science: Like cartilage, but simpler

    DEFF Research Database (Denmark)

    Skov, Anne Ladegaard

    2015-01-01

    The properties of articular cartilage, which lines bones in joints, depend partlyon repulsion between components of the material. A new synthetic gel that mimics this feature has rare, direction-dependent properties.......The properties of articular cartilage, which lines bones in joints, depend partlyon repulsion between components of the material. A new synthetic gel that mimics this feature has rare, direction-dependent properties....

  1. Elemental and structural studies at the bone-cartilage interface

    Energy Technology Data Exchange (ETDEWEB)

    Kaabar, W., E-mail: w.kaabar@surrey.ac.uk [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Daar, E. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Bunk, O. [Swiss Light Source, Paul Scherrer Institute, 5232 Villigen (Switzerland); Farquharson, M.J. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1 (Canada); Laklouk, A. [Al-Fateh University, Tripoli (Libya); Bailey, M.; Jeynes, C. [Surrey Ion Beam Centre, University of Surrey, Guildford GU2 7XH (United Kingdom); Gundogdu, O. [Umuttepe Campus, University of Kocaeli, 41380 Kocaeli (Turkey); Bradley, D.A. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom)

    2011-10-01

    Micro-Proton Induced X-ray Emission ({mu}-PIXE) and Proton Induced Gamma-ray Emission (PIGE) techniques were employed in the investigation of trace and essential elements distribution in normal and diseased human femoral head sections affected by osteoarthritis (OA). PIGE was exploited in the determination of elements of low atomic number z<15 such as Na and F whereas elements with z>15 viz Ca, Z, P and S were determined by PIXE. Accumulations of key elements in the bone and cartilage sections were observed, significant S and Na concentrations being found in the cartilage region particularly in normal tissues. Zn showed enhanced concentrations at the bone-cartilage interface. At a synchrotron facility, small angle X-ray scattering (SAXS) was utilized on a decalcified human femoral head section affected by OA, direct measurements being made of spatial alterations of collagen fibres. The SAXS results showed a slight decrease in the axial periodicity between normal collagen type I and that in diseased tissue in various sites, in contrast with the findings of others.

  2. Measurements of electron avalanche formation time in W-band microwave air breakdown

    International Nuclear Information System (INIS)

    We present measurements of formation times of electron avalanche ionization discharges induced by a focused 110 GHz millimeter-wave beam in atmospheric air. Discharges take place in a free volume of gas, with no nearby surfaces or objects. When the incident field amplitude is near the breakdown threshold for pulsed conditions, measured formation times are ∼0.1-2 μs over the pressure range 5-700 Torr. Combined with electric field breakdown threshold measurements, the formation time data shows the agreement of 110 GHz air breakdown with the similarity laws of gas discharges.

  3. Measurements of electron avalanche formation time in W-band microwave air breakdown

    Science.gov (United States)

    Cook, Alan M.; Hummelt, Jason S.; Shapiro, Michael A.; Temkin, Richard J.

    2011-08-01

    We present measurements of formation times of electron avalanche ionization discharges induced by a focused 110 GHz millimeter-wave beam in atmospheric air. Discharges take place in a free volume of gas, with no nearby surfaces or objects. When the incident field amplitude is near the breakdown threshold for pulsed conditions, measured formation times are ˜0.1-2 μs over the pressure range 5-700 Torr. Combined with electric field breakdown threshold measurements, the formation time data shows the agreement of 110 GHz air breakdown with the similarity laws of gas discharges.

  4. The in vitro and in vivo capacity of culture-expanded human cells from several sources encapsulated in alginate to form cartilage

    Directory of Open Access Journals (Sweden)

    MM Pleumeekers

    2014-04-01

    Full Text Available Cartilage has limited self-regenerative capacity. Tissue engineering can offer promising solutions for reconstruction of missing or damaged cartilage. A major challenge herein is to define an appropriate cell source that is capable of generating a stable and functional matrix. This study evaluated the performance of culture-expanded human chondrocytes from ear (EC, nose (NC and articular joint (AC, as well as bone-marrow-derived and adipose-tissue-derived mesenchymal stem cells both in vitro and in vivo. All cells (≥ 3 donors per source were culture-expanded, encapsulated in alginate and cultured for 5 weeks. Subsequently, constructs were implanted subcutaneously for 8 additional weeks. Before and after implantation, glycosaminoglycan (GAG and collagen content were measured using biochemical assays. Mechanical properties were determined using stress-strain-indentation tests. Hypertrophic differentiation was evaluated with qRT-PCR and subsequent endochondral ossification with histology. ACs had higher chondrogenic potential in vitro than the other cell sources, as assessed by gene expression and GAG content (p < 0.001. However, after implantation, ACs did not further increase their matrix. In contrast, ECs and NCs continued producing matrix in vivo leading to higher GAG content (p < 0.001 and elastic modulus. For NC-constructs, matrix-deposition was associated with the elastic modulus (R2 = 0.477, p = 0.039. Although all cells – except ACs – expressed markers for hypertrophic differentiation in vitro, there was no bone formed in vivo. Our work shows that cartilage formation and functionality depends on the cell source used. ACs possess the highest chondrogenic capacity in vitro, while ECs and NCs are most potent in vivo, making them attractive cell sources for cartilage repair.

  5. Rho GTPase protein Cdc42 is critical for postnatal cartilage development.

    Science.gov (United States)

    Nagahama, Ryo; Yamada, Atsushi; Tanaka, Junichi; Aizawa, Ryo; Suzuki, Dai; Kassai, Hidetoshi; Yamamoto, Matsuo; Mishima, Kenji; Aiba, Atsu; Maki, Koutaro; Kamijo, Ryutaro

    2016-02-19

    Cdc42, a small Rho GTPase family member, has been shown to regulate multiple cellular functions in vitro, including actin cytoskeletal reorganization, cell migration, proliferation, and gene expression. However, its tissue-specific roles in vivo remain largely unknown, especially in postnatal cartilage development, as cartilage-specific Cdc42 inactivated mice die within a few days after birth. In this study, we investigated the physiological functions of Cdc42 during cartilage development after birth using tamoxifen-induced cartilage-specific inactivated Cdc42 conditional knockout (Cdc42 (fl/fl); Col2-CreERT) mice, which were generated by crossing Cdc42 flox mice (Cdc42 (fl/fl)) with tamoxifen-induced type II collagen (Col2) Cre transgenic mice using a Cre/loxP system. The gross morphology of the Cdc42 cKO mice was shorter limbs and body, as well as reduced body weight as compared with the controls. In addition, severe defects were found in growth plate chondrocytes of the long bones, characterized by a shorter proliferating zone (PZ), wider hypertrophic zone (HZ), and loss of columnar organization of proliferating chondrocytes, resulting in delayed endochondral bone formation associated with abnormal bone growth. Our findings demonstrate the importance of Cdc42 for cartilage development during both embryonic and postnatal stages. PMID:26820532

  6. In end stage osteoarthritis, cartilage tissue pentosidine levels are inversely related to parameters of cartilage damage

    NARCIS (Netherlands)

    Vos, P.A.J.M.; Mastbergen, S.C.; Huisman, A.M.; Boer, T.N.de; Groot, J.de; Polak, A.A.; Lafeber, F.P.J.G.

    2012-01-01

    Objectives: Age is the most prominent predisposition for development of osteoarthritis (OA). Age-related changes of articular cartilage are likely to play a role. Advanced glycation endproducts (AGEs) accumulate in cartilage matrix with increasing age and adversely affect the biomechanical propertie

  7. Increasing thickness and fibrosis of the cartilage in acetabular dysplasia: a rabbit model research

    Institute of Scientific and Technical Information of China (English)

    LI Tian-you; MA Rui-xue

    2010-01-01

    Background The order and mechanism of pathological changes in acetabular dysplasia are still unclear. This study investigated cartilage changes in rabbit acetabular dysplasia models at different ages.Methods Twenty-seven 1-month-old New Zealand rabbits underwent cast immobilization of the left hind limb in knee extension. Serial acetabular dysplasia models were established by assessment of the acetabular index and Sharp's angle on radiographs. The thickness of the acetabular cartilage was measured under a microscope, and fibrosis was observed. Ultrastructural changes were investigated with scanning electron microscopy and transmission electron microscopy. The messenger RNA expression of collagen Ⅰ and Ⅱ, β1 integrin, and caspase-9 were measured by real-time fluorescence quantitative polymerase chain reaction.Results In an immature group of rabbits, the acetabular index of the treated hip increased with animal growth. The cartilage on the brim of the left acetabulum was significantly thicker than that on the right side. The collagen fibrils on the surface of the cartilage became gross, and the chondrocytes in the enlargement layer underwent necrosis. In a mature group of rabbits, the left Sharp's angle increased in the rabbits with 6-week casting. The cartilage on the brim of the left acetabulum underwent fibrosis. The chondrocytes were weakly stained, and the number of lysosomes was much larger than normal. The messenger RNA expression of collagen Ⅰ and Ⅱ, β1 integrin, and caspase-9 in the cartilage differed significantly at different ages.Conclusions Increasing thickness followed by fibrosis may be the order of pathological cartilage changes in acetabular dysplasia, with changes in ultrastructure and collagen expression contributing to the process.

  8. Microstructural modeling of collagen network mechanics and interactions with the proteoglycan gel in articular cartilage.

    Science.gov (United States)

    Quinn, T M; Morel, V

    2007-01-01

    Cartilage matrix mechanical function is largely determined by interactions between the collagen fibrillar network and the proteoglycan gel. Although the molecular physics of these matrix constituents have been characterized and modern imaging methods are capable of localized measurement of molecular densities and orientation distributions, theoretical tools for using this information for prediction of cartilage mechanical behavior are lacking. We introduce a means to model collagen network contributions to cartilage mechanics based upon accessible microstructural information (fibril density and orientation distributions) and which self-consistently follows changes in microstructural geometry with matrix deformations. The interplay between the molecular physics of the collagen network and the proteoglycan gel is scaled up to determine matrix material properties, with features such as collagen fibril pre-stress in free-swelling cartilage emerging naturally and without introduction of ad hoc parameters. Methods are developed for theoretical treatment of the collagen network as a continuum-like distribution of fibrils, such that mechanical analysis of the network may be simplified by consideration of the spherical harmonic components of functions of the fibril orientation, strain, and stress distributions. Expressions for the collagen network contributions to matrix stress and stiffness tensors are derived, illustrating that only spherical harmonic components of orders 0 and 2 contribute to the stress, while orders 0, 2, and 4 contribute to the stiffness. Depth- and compression-dependent equilibrium mechanical properties of cartilage matrix are modeled, and advantages of the approach are illustrated by exploration of orientation and strain distributions of collagen fibrils in compressed cartilage. Results highlight collagen-proteoglycan interactions, especially for very small physiological strains where experimental data are relatively sparse. These methods for

  9. Objective tools to analyze the lower lateral cartilage in unilateral cleft lip nasal deformities.

    Science.gov (United States)

    Saleh, Mohamed A; Elshahat, Ahmed; Emara, Maher; Hussein, Heba; Gould, Lisa; Smith, David; Awad, Mostafa A

    2011-07-01

    Correction of cleft lip nasal deformity is an elusive goal. A controversy exists regarding the cause of the deformity, and therefore, there is a controversy of how to correct the deformity. Extrinsic theory is based on the presence of deformational forces from outside. The intrinsic theory is associated with deficiency of the lower lateral cartilage. The aim of this study was to use new objective tools to compare morphologically and histologically between the lower lateral cartilages of cleft and noncleft sides in patients with unilateral cleft lip nasal deformity. This study included 16 patients. They were operated on to correct unilateral cleft lip nasal deformity. Length, width, and thickness of lateral crura of the lower lateral cartilages of cleft and noncleft sides were measured. Punch biopsies from the middle part of the caudal ends of lateral crura were taken and sent for histologic and immunohistochemical studies. The lateral crura of the cleft side were significantly wider and shorter and tend to be thinner than those of the noncleft side. There was no significant difference in the chondroblast, chondrocyte, and total cellular number in the lower lateral cartilage of the cleft and noncleft sides. There was significantly less glycosaminoglycan content in the ground matrix of the lower lateral cartilage of cleft side. In conclusion, the use of digital sliding caliber in measuring the diminutions of the lower lateral cartilage and image analyzer to quantify the proteoglycans, glycosaminoglycans, fibroblast growth factor 18, and collagen content is very effective objective tools to compare the cleft and noncleft alar cartilage. PMID:21772161

  10. Tissue engineering strategies to study cartilage development, degeneration and regeneration.

    Science.gov (United States)

    Bhattacharjee, Maumita; Coburn, Jeannine; Centola, Matteo; Murab, Sumit; Barbero, Andrea; Kaplan, David L; Martin, Ivan; Ghosh, Sourabh

    2015-04-01

    Cartilage tissue engineering has primarily focused on the generation of grafts to repair cartilage defects due to traumatic injury and disease. However engineered cartilage tissues have also a strong scientific value as advanced 3D culture models. Here we first describe key aspects of embryonic chondrogenesis and possible cell sources/culture systems for in vitro cartilage generation. We then review how a tissue engineering approach has been and could be further exploited to investigate different aspects of cartilage development and degeneration. The generated knowledge is expected to inform new cartilage regeneration strategies, beyond a classical tissue engineering paradigm.

  11. Measurements of the Suitability of Large Rock Salt Formations for Radio Detection of High Energy Neutrinos

    OpenAIRE

    Gorham, Peter; Saltzberg, David; Odian, Allen; Williams, Dawn; Besson, David; Frichter, George; Tantawi, Sami

    2001-01-01

    We have investigated the possibility that large rock salt formations might be suitable as target masses for detection of neutrinos of energies about 10 PeV and above. In neutrino interactions at these energies, the secondary electromagnetic cascade produces a coherent radio pulse well above ambient thermal noise via the Askaryan effect. We describe measurements of radio-frequency attenuation lengths and ambient thermal noise in two salt formations. Measurements in the Waste Isolation Pilot Pl...

  12. Electrowetting on dielectric-based microfluidics for integrated lipid bilayer formation and measurement

    Science.gov (United States)

    Poulos, Jason L.; Nelson, Wyatt C.; Jeon, Tae-Joon; Kim, Chang-Jin ``Cj''; Schmidt, Jacob J.

    2009-07-01

    We present a microfluidic platform for the formation and electrical measurement of lipid bilayer membranes. Using electrowetting on dielectric (EWOD), two or more aqueous droplets surrounded by a lipid-containing organic phase were manipulated into contact to form a lipid bilayer at their interface. Thin-film Ag/AgCl electrodes integrated into the device enabled electrical measurement of membrane formation and the incorporation of gramicidin channels of two bilayers in parallel.

  13. Quantitative MRI Evaluation of Articular Cartilage Using T2 Mapping Following Hip Arthroscopy for Femoroacetabular Impingement

    Science.gov (United States)

    Mayer, Stephanie W.; Wagner, Naomi; Fields, Kara G.; Wentzel, Catherine; Burge, Alissa; Potter, Hollis G.; Lyman, Stephen; Kelly, Bryan T.

    2016-01-01

    acetabular cartilage (p= 0.133 - 0.966). Conclusion: There was no significant progression of acetabular cartilage degeneration as measured by structural collagen organization and integrity on T2 mapping from pre-operative imaging to the time of two year follow up. Based on this data, it appears that hip arthroscopy for decompression of cam- type FAI slows or halts the process of cartilage degeneration caused by the mechanical wear known to occur in cam-type FAI which is associated with progression to osteoarthritis.

  14. Cdc42 is critical for cartilage development during endochondral ossification.

    Science.gov (United States)

    Suzuki, Wataru; Yamada, Atsushi; Aizawa, Ryo; Suzuki, Dai; Kassai, Hidetoshi; Harada, Takeshi; Nakayama, Mutsuko; Nagahama, Ryo; Maki, Koutaro; Takeda, Shu; Yamamoto, Matsuo; Aiba, Atsu; Baba, Kazuyoshi; Kamijo, Ryutaro

    2015-01-01

    Cdc42 is a widely expressed protein that belongs to the family of Rho GTPases and controls a broad variety of signal transduction pathways in a variety of cell types. To investigate the physiological functions of Cdc42 during cartilage development, we generated chondrocyte-specific inactivated Cdc42 mutant mice (Cdc42(fl/fl); Col2-Cre). The gross morphology of mutant neonates showed shorter limbs and body as compared with the control mice (Cdc42(fl/fl)). Skeletal preparations stained with alcian blue and alizarin red also revealed that the body and the long bone length of the mutants were shorter than those of the control mice. Furthermore, severe defects were found in growth plate chondrocytes in the femur sections of mutant mice, characterized by a reduced proliferating zone height, wider hypertrophic zone, and loss of columnar organization in proliferating chondrocytes. The expression levels of chondrocyte marker genes, such as Col2, Col10, and Mmp13, in mutant mice were decreased as compared with the control mice. Mineralization of trabecular bones in the femur sections was also decreased in the mutants as compared with control mice, whereas osteoid volume was increased. Together these results suggested that chondrocyte proliferation and differentiation in growth plates in the present mutant mice were not normally organized, which contributed to abnormal bone formation. We concluded that Cdc42 is essential for cartilage development during endochondral bone formation. PMID:25343271

  15. Medial meniscal posterior root/horn radial tears correlate with cartilage degeneration detected by T1ρ relaxation mapping

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Kenji, E-mail: Kenji-am@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Hashimoto, Sanshiro, E-mail: info@msorc.jp [Minami-Shinjuku Orthopaedic Rehabilitation Clinic, 2-16-7 Yoyogi, Shibuya-ku, Tokyo 151-0053 (Japan); Nakamura, Hiroshi, E-mail: nakamura@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Mori, Atsushi, E-mail: atsu@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Sato, Akiko, E-mail: akiko-sato@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Majima, Tokifumi, E-mail: tkmajima@iuhw.ac.jp [Department of Orthopaedic Surgery, International University of Health and Welfare Hospital, 537-3 Iguchi, Nasu-shiobara, Tochigi 329-2763 (Japan); Takai, Shinro, E-mail: takai-snr@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan)

    2015-06-15

    Highlights: • Posterior radial tears in medial meniscus associate T1ρ values of cartilage. • Posterior radial tears relate to cartilage degeneration even in early-stage osteoarthritis. • Abnormalities in meniscus on MRI are useful for screening early-stage osteoarthritis. - Abstract: Objective: This study aimed to identify factors on routine pulse sequence MRI associated with cartilage degeneration observed on T1ρ relaxation mapping. Materials and methods: This study included 137 subjects with knee pain. T1ρ values were measured in the regions of interest on the surface layer of the cartilage on mid-coronal images of the femorotibial joint. Assessment of cartilage, subchondral bone, meniscus and ligaments was performed using routine pulse sequence MRI. Radiographic evaluation for osteoarthritis was also performed. Results: Multiple regression analysis revealed posterior root/horn tears to be independent factors increasing the T1ρ values of the cartilage in the medial compartment of the femorotibial joint. Even when adjusted for radiographically defined early-stage osteoarthritis, medial posterior meniscal radial tears significantly increased the T1ρ values. Conclusions: This study showed that posterior root/horn radial tears in the medial meniscus are particularly important MRI findings associated with cartilage degeneration observed on T1ρ relaxation mapping. Morphological factors of the medial meniscus on MRI provide findings useful for screening early-stage osteoarthritis.

  16. Priming Adipose-Derived Mesenchymal Stem Cells with Hyaluronan Alters Growth Kinetics and Increases Attachment to Articular Cartilage

    Directory of Open Access Journals (Sweden)

    Peter Succar

    2016-01-01

    Full Text Available Background. Biological therapeutics such as adipose-derived mesenchymal stem cell (MSC therapy are gaining acceptance for knee-osteoarthritis (OA treatment. Reports of OA-patients show reductions in cartilage defects and regeneration of hyaline-like-cartilage with MSC-therapy. Suspending MSCs in hyaluronan commonly occurs in animals and humans, usually without supporting data. Objective. To elucidate the effects of different concentrations of hyaluronan on MSC growth kinetics. Methods. Using a range of hyaluronan concentrations, we measured MSC adherence and proliferation on culture plastic surfaces and a novel cartilage-adhesion assay. We employed time-course and dispersion imaging to assess MSC binding to cartilage. Cytokine profiling was also conducted on the MSC-secretome. Results. Hyaluronan had dose-dependent effects on growth kinetics of MSCs at concentrations of entanglement point (1 mg/mL. At higher concentrations, viscosity effects outweighed benefits of additional hyaluronan. The cartilage-adhesion assay highlighted for the first time that hyaluronan-primed MSCs increased cell attachment to cartilage whilst the presence of hyaluronan did not. Our time-course suggested patients undergoing MSC-therapy for OA could benefit from joint-immobilisation for up to 8 hours. Hyaluronan also greatly affected dispersion of MSCs on cartilage. Conclusion. Our results should be considered in future trials with MSC-therapy using hyaluronan as a vehicle, for the treatment of OA.

  17. Fractional-order elastic models of cartilage: A multi-scale approach

    Science.gov (United States)

    Magin, Richard L.; Royston, Thomas J.

    2010-03-01

    The objective of this research is to develop new quantitative methods to describe the elastic properties (e.g., shear modulus, viscosity) of biological tissues such as cartilage. Cartilage is a connective tissue that provides the lining for most of the joints in the body. Tissue histology of cartilage reveals a multi-scale architecture that spans a wide range from individual collagen and proteoglycan molecules to families of twisted macromolecular fibers and fibrils, and finally to a network of cells and extracellular matrix that form layers in the connective tissue. The principal cells in cartilage are chondrocytes that function at the microscopic scale by creating nano-scale networks of proteins whose biomechanical properties are ultimately expressed at the macroscopic scale in the tissue's viscoelasticity. The challenge for the bioengineer is to develop multi-scale modeling tools that predict the three-dimensional macro-scale mechanical performance of cartilage from micro-scale models. Magnetic resonance imaging (MRI) and MR elastography (MRE) provide a basis for developing such models based on the nondestructive biomechanical assessment of cartilage in vitro and in vivo. This approach, for example, uses MRI to visualize developing proto-cartilage structure, MRE to characterize the shear modulus of such structures, and fractional calculus to describe the dynamic behavior. Such models can be extended using hysteresis modeling to account for the non-linear nature of the tissue. These techniques extend the existing computational methods to predict stiffness and strength, to assess short versus long term load response, and to measure static versus dynamic response to mechanical loads over a wide range of frequencies (50-1500 Hz). In the future, such methods can perhaps be used to help identify early changes in regenerative connective tissue at the microscopic scale and to enable more effective diagnostic monitoring of the onset of disease.

  18. Effects of refrigeration and freezing on the electromechanical and biomechanical properties of articular cartilage.

    Science.gov (United States)

    Changoor, Adele; Fereydoonzad, Liah; Yaroshinsky, Alex; Buschmann, Michael D

    2010-06-01

    In vitro electromechanical and biomechanical testing of articular cartilage provide critical information about the structure and function of this tissue. Difficulties obtaining fresh tissue and lengthy experimental testing procedures often necessitate a storage protocol, which may adversely affect the functional properties of cartilage. The effects of storage at either 4°C for periods of 6 days and 12 days, or during a single freeze-thaw cycle at -20°C were examined in young bovine cartilage. Non-destructive electromechanical measurements and unconfined compression testing on 3 mm diameter disks were used to assess cartilage properties, including the streaming potential integral (SPI), fibril modulus (Ef), matrix modulus (Em), and permeability (k). Cartilage disks were also examined histologically. Compared with controls, significant decreases in SPI (to 32.3±5.5% of control values, prefrigeration at 4°C, but no significant changes were detected at day 6. A trend toward detecting a decrease in SPI (to 94.2±6.2% of control values, p=0.083) was identified following a single freeze-thaw cycle, but no detectable changes were observed for any biomechanical parameters. All numbers are mean±95% confidence interval. These results indicate that fresh cartilage can be stored in a humid chamber at 4°C for a maximum of 6 days with no detrimental effects to cartilage electromechanical and biomechanical properties, while one freeze-thaw cycle produces minimal deterioration of biomechanical and electromechanical properties. A comparison to literature suggested that particular attention should be paid to the manner in which specimens are thawed after freezing, specifically by minimizing thawing time at higher temperatures. PMID:20887036

  19. Human stem cells and articular cartilage regeneration.

    Science.gov (United States)

    Inui, Atsuyuki; Iwakura, Takashi; Reddi, A Hari

    2012-11-05

    The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES) cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS) cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  20. Polarized IR microscopic imaging of articular cartilage

    Science.gov (United States)

    Ramakrishnan, Nagarajan; Xia, Yang; Bidthanapally, Aruna

    2007-08-01

    The objective of this spectroscopic imaging study is to understand the anisotropic behavior of articular cartilage under polarized infrared radiation at 6.25 µm pixel resolution. Paraffin embedded canine humeral cartilage-bone blocks were used to obtain 6 µm thick tissue sections. Two wire grid polarizers were used to manipulate the polarization states of IR radiation by setting them for various polarizer/analyzer angles. The characteristics of the major chemical components (amide I, amide II, amide III and sugar) of articular cartilage were investigated using (a) a polarizer and (b) a combination of a polarizer and an analyzer. These results were compared to those obtained using only an analyzer. The infrared anisotropy (variation in infrared absorption as a function of polarization angles) of amide I, amide II and amide III bands correlates with the orientation of collagen fibrils along the tissue depth in different histological zones. An 'anisotropic flipping' region of amide profiles indicates the possibility of using Fourier transform infrared imaging (FTIRI) to determine the histological zones in cartilage. Cross-polarization experiment indicates the resolution of overlapping peaks of collagen triple helix and/or proteoglycan in articular cartilage.

  1. Thermogravimetry of irradiated human costal cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Martinho Junior, Antonio C.; Machado, Luci D.B.; Dias, Djalma B.; Mathor, Monica B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: antonio_carlos_martinho@msn.com; lmachado@ipen.br; dbdias@ipen.br; mathor@ipen.br; Herson, Marisa R. [Universidade de Sao Paulo, SP (Brazil). Hospital das Clinicas. Banco de Tecidos do Instituto Central]. E-mail: marisah@vifm.org; Meumann, Nilton F.; Pasqualucci, Carlos Augusto G. [Universidade de Sao Paulo, SP (Brazil). Faculdade de Medicina. Servico de Verificacao de Obitos]. E-mail: svoc@usp.br

    2007-07-01

    Costal cartilage has been sterilized with gamma radiation using {sup 60}Co sources at two different doses, 25 kGy and 50 kGy, for storage in tissue banks. Samples of costal cartilage were deep-freezing as method of preservation. Thermogravimetry (Shimadzu TGA-50) was used to verify the water release of costal cartilage before and after irradiation. The TG tests were carried out at heating rate of 10 deg C/min from room temperature to 600 deg C under a flow rate of 50 mL/min of compressed air. Samples of costal cartilage were divided in 2 parts. One part of them was kept as reference material; the other part was irradiated. This procedure assures better homogeneity of the sample and reproducibility of the experimental results. The obtained data have shown that the TG curves have the same pattern, independently of the sample. Non-irradiated samples showed great variability of thermogravimetric curves among different donors and for the same donor. Further experimental work is being carried out on human cartilage preserved in glycerol in high concentration (> 98%) to compare with those deep freezing. (author)

  2. Human Stem Cells and Articular Cartilage Regeneration

    Directory of Open Access Journals (Sweden)

    A. Hari Reddi

    2012-11-01

    Full Text Available  The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  3. Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC shows no change in cartilage structural composition after viscosupplementation in patients with early-stage knee osteoarthritis.

    Directory of Open Access Journals (Sweden)

    Jasper van Tiel

    Full Text Available INTRODUCTION: Viscosupplementation with hyaluronic acid (HA of osteoarthritic (OA knee joints has a well-established positive effect on clinical symptoms. This effect, however, is only temporary and the working mechanism of HA injections is not clear. It was suggested that HA might have disease modifying properties because of its beneficial effect on cartilage sulphated glycosaminoglycan (sGAG content. Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC is a highly reproducible, non-invasive surrogate measure for sGAG content and hence composition of cartilage. The aim of this study was to assess whether improvement in cartilage structural composition is detected using dGEMRIC 14 weeks after 3 weekly injections with HA in patients with early-stage knee OA. METHODS: In 20 early-stage knee OA patients (KLG I-II, 3D dGEMRIC at 3T was acquired before and 14 weeks after 3 weekly injections with HA. To evaluate patient symptoms, the knee injury and osteoarthritis outcome score (KOOS and a numeric rating scale (NRS for pain were recorded. To evaluate cartilage composition, six cartilage regions in the knee were analyzed on dGEMRIC. Outcomes of dGEMRIC, KOOS and NRS before and after HA were compared using paired t-testing. Since we performed multiple t-tests, we applied a Bonferroni-Holm correction to determine statistical significance for these analyses. RESULTS: All KOOS subscales ('pain', 'symptoms', 'daily activities', 'sports' and 'quality of life' and the NRS pain improved significantly 14 weeks after Viscosupplementation with HA. Outcomes of dGEMRIC did not change significantly after HA compared to baseline in any of the cartilage regions analyzed in the knee. CONCLUSIONS: Our results confirm previous findings reported in the literature, showing persisting improvement in symptomatic outcome measures in early-stage knee OA patients 14 weeks after Viscosupplementation. Outcomes of dGEMRIC, however, did not change after Viscosupplementation

  4. The discrimination of type I and type II collagen and the label-free imaging of engineered cartilage tissue.

    Science.gov (United States)

    Su, Ping-Jung; Chen, Wei-Liang; Li, Tsung-Hsien; Chou, Chen-Kuan; Chen, Te-Hsuen; Ho, Yi-Yun; Huang, Chi-Hsiu; Chang, Shwu-Jen; Huang, Yi-You; Lee, Hsuan-Shu; Dong, Chen-Yuan

    2010-12-01

    Using excitation polarization-resolved second harmonic generation (SHG) microscopy, we measured SHG intensity as a function of the excitation polarization angle for type I and type II collagens. We determined the second order susceptibility (χ((2))) tensor ratios of type I and II collagens at each pixel, and displayed the results as images. We found that the χ((2)) tensor ratios can be used to distinguish the two types of collagen. In particular, we obtained χ(zzz)/χ(zxx) = 1.40 ± 0.04 and χ(xzx)/χ(zxx) = 0.53 ± 0.10 for type I collagen from rat tail tendon, and χ(zzz)/χ(zxx) = 1.14 ± 0.09 and χ(xzx)/χ(zxx) = 0.29 ± 0.11 for type II collagen from rat trachea cartilage. We also applied this methodology on the label-free imaging of engineered cartilage tissue which produces type I and II collagen simultaneously. By displaying the χ((2)) tensor ratios in the image format, the variation in the χ((2)) tensor ratios can be used as a contrast mechanism for distinguishing type I and II collagens. PMID:20875682

  5. A comparative Study between the Structure of Cartilage Tissue Produced from Murine MSCs Differentiation and Hyaline Costal Cartilage

    Directory of Open Access Journals (Sweden)

    M.R. Baghban Eslaminezhad, Ph.D.

    2007-09-01

    Full Text Available Background and purpose: Vitro cartilage differentiation of mesenchymal stem cells (MSCs has been noticed in several investigations. In this regard, almost always molecular differentiation of the cells has been examined, while structural and morphological differentiation of them has been ignored. Therefore, the present study examines the structure and ultrastructure of the cartilage differentiated from murine MSCs compared with that of costal cartilage.Materials and Methods: 2× 105 MSCs isolated from the bone marrow of NMRI mice were pleted by centrifugation and cultured for 21 days in chondrogenic medium. At the end of cultivation period, occurrence of chondrogenic differentiation was confirmed by reverse transcriptase–polymerase chain reaction (RT-PCR analysis for some cartilage-specific genes. To compare the structure of differentiated tissue with that of natural cartilage, the cartilage was differentiated from MSCs and the cartilage obtained from the same murine rib was prepared for transmission electron microscopy (TEM.Results: Structural studies indicated that similar to the costal cartilage, the cartilage produced from differentiation of perichondrium-like layer was formed. According to the microscopic images, in contrast to costal chondrocytes, the differentiated cells had euchromatic nucleus and their cytoplasm contained plenty of the organelles involved in active cell secretion. Furthermore, intercellular matrix in differentiated cartilage had a fibrillar appearance. Conclusion: Our results indicated that the structure of cartilage produced in micro mass culture system is somewhat different from that of costal cartilage. The cells from differentiated tissue seemed to be more active than those from costal cartilage. .

  6. Detecting ICRS grade 1 cartilage lesions in anterior cruciate ligament injury using T1ρ and T2 mapping

    Energy Technology Data Exchange (ETDEWEB)

    Nishioka, Hiroaki, E-mail: kinuhnishiok@fc.kuh.kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Hirose, Jun, E-mail: hirojun-mk@umin.ac.jp [Department of Orthopaedic Surgery, Kumamoto University Hospital, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Nakamura, Eiichi, E-mail: h@kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Okamoto, Nobukazu, E-mail: nobuoka9999@fc.kuh.kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Karasugi, Tatsuki, E-mail: tatsukik@fc.kuh.kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Taniwaki, Takuya, E-mail: takuyataniwaki@fc.kuh.kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Okada, Tatsuya, E-mail: tatsuya-okada@fc.kuh.kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Yamashita, Yasuyuki, E-mail: yama@kumamoto-u.ac.jp [Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Mizuta, Hiroshi, E-mail: mizuta@kumamoto-u.ac.jp [Department of Orthopaedic Surgery, Faculty of Life Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan)

    2013-09-15

    Objective: The purpose of this study was to clarify the detectability of the International Cartilage Repair Society (ICRS) grade 1 cartilage lesions in anterior cruciate ligament (ACL)–injured knees using T1ρ and T2 mapping. Materials and Methods: We performed preoperative T1ρ and T2 mapping and 3D gradient–echo with water–selective excitation (WATS) sequences on 37 subjects with ACL injuries. We determined the detectability on 3D WATS based on arthroscopic findings. The T1ρ and T2 values (ms) were measured in the regions of interest that were placed on the weight–bearing cartilage of the femoral condyle. The receiver operating characteristic (ROC) curve based on these values was constructed using the arthroscopic findings as a reference standard. The evaluation of cartilage was carried out only in the weight–bearing cartilage. The cut–off values for determining the presence of a cartilage injury were determined using each ROC curve, and the detectability was calculated for the T1ρ and T2 mapping. Results: The cut–off values for the T1ρ and T2 were 41.6 and 41.2, respectively. The sensitivity and specificity of T1ρ were 91.2% and 89.5%, respectively, while those of T2 were 76.5% and 81.6%, respectively. For the 3D WATS images, the same values were 58.8% and 78.9%, respectively. Conclusions: Our study demonstrated that the T1ρ and T2 values were significantly higher for ICRS grade 1 cartilage lesions than for normal cartilage and that the two mappings were able to non–invasively detect ICRS grade 1 cartilage lesions in the ACL–injured knee with a higher detectability than were 3D WATS images.

  7. Alternative Measurement Paradigms for Measuring Executive Functions: SEM (Formative and Reflective Models) and IRT (Rasch Models)

    Science.gov (United States)

    Engelhard, George, Jr.; Wang, Jue

    2014-01-01

    The authors of the Focus article pose important questions regarding whether or not performance-based tasks related to executive functioning are best viewed as reflective or formative indicators. Miyake and Friedman (2012) define executive functioning (EF) as "a set of general-purpose control mechanisms, often linked to the prefrontal cortex…

  8. Preparation and characterization of a decellularized cartilage scaffold for ear cartilage reconstruction

    International Nuclear Information System (INIS)

    Scaffolds are widely used to reconstruct cartilage. Yet, the fabrication of a scaffold with a highly organized microenvironment that closely resembles native cartilage remains a major challenge. Scaffolds derived from acellular extracellular matrices are able to provide such a microenvironment. Currently, no report specifically on decellularization of full thickness ear cartilage has been published. In this study, decellularized ear cartilage scaffolds were prepared and extensively characterized. Cartilage decellularization was optimized to remove cells and cell remnants from elastic cartilage. Following removal of nuclear material, the obtained scaffolds retained their native collagen and elastin contents as well as their architecture and shape. High magnification scanning electron microscopy showed no obvious difference in matrix density after decellularization. However, glycosaminoglycan content was significantly reduced, resulting in a loss of viscoelastic properties. Additionally, in contact with the scaffolds, human bone-marrow-derived mesenchymal stem cells remained viable and are able to differentiate toward the chondrogenic lineage when cultured in vitro. These results, including the ability to decellularize whole human ears, highlight the clinical potential of decellularization as an improved cartilage reconstruction strategy. (paper)

  9. Engineering articular cartilage using newly developed carrageenan basedhydrogels

    OpenAIRE

    Popa, Elena Geta

    2014-01-01

    Articular cartilage holds specific functionality in the human body creating smooth gliding areas and allowing the joints to move easily without pain. However, due to its avascular nature and to the low metabolic activity of the constituent cells-the chondrocytes, cartilage has a low regenerative potential. The current surgical options to treat damaged cartilage are not long lasting and involve frequent revisions. Tissue engineering may provide an alternative approach for cartilage...

  10. Type III Collagen, a Fibril Network Modifier in Articular Cartilage*

    OpenAIRE

    Wu, Jiann-Jiu; Weis, Mary Ann; Kim, Lammy S.; Eyre, David R.

    2010-01-01

    The collagen framework of hyaline cartilages, including articular cartilage, consists largely of type II collagen that matures from a cross-linked heteropolymeric fibril template of types II, IX, and XI collagens. In the articular cartilages of adult joints, type III collagen makes an appearance in varying amounts superimposed on the original collagen fibril network. In a study to understand better the structural role of type III collagen in cartilage, we find that type III collagen molecules...

  11. Development of artificial articular cartilage

    Indian Academy of Sciences (India)

    Biswajit Bera

    2009-10-01

    The present study describes the development of artificial articular cartilage on the basis of mimicking structural gel properties and mechanical gel properties of natural articular cartilage. It is synthesized from PVA/Si nanocomposite containing 20% Tetra ethoxy silane (TEOS) by sol–gel method. Mechanical strength of Poly(vinyl alcohol), PVA is improved up to 35 MPa. Manufacturing method is adopted considering colloidal stability of nano silica particle in PVA sol at specific pH = 1. An adhesive is also prepared from PVA/Si nanocomposite containing 40% TEOS for firm attachment of artificial articular cartilage on underlying bone with high bond strength.

  12. Cartilage quality in finger joints. Delayed Gd(DTPA){sup 2-} enhanced MRI of the cartilage (dGEMRIC) at 3T; Knorpelqualitaet an den Fingergelenken. Delayed Gd(DTPA){sup 2-} enhanced MRI of the cartilage (dGEMRIC) bei 3T

    Energy Technology Data Exchange (ETDEWEB)

    [Miese, F.R.; Wittsack, H.J. (Duesseldorf Univ. (DE). Inst. fuer Radiologie); Ostendorf, B. (Duesseldorf Univ. (DE). Klinik fuer Endokrinologie, Diabetologie und Rheumatologie)] (and others)

    2010-10-15

    Purpose: To evaluate the feasibility of molecular cartilage MRI in finger joints. Materials and Methods: Delayed Gd(DTPA){sup 2-} enhanced MRI of the cartilage (dGEMRIC) using a variable flip angle approach (VFA) was performed for the metacarpophalangeal (MCP) joints II and III in nine healthy volunteers and eighteen patients with rheumatoid arthritis (RA). The cartilage thickness was measured. Additionally, dGEMRIC was performed on proximal interphalangeal joints (PIP) in two patients with finger osteoarthritis (OA). Results: the dGEMRIC index of the four evaluated cartilage areas was significantly decreased in RA patients compared to healthy subjects. The dGEMRIC index of MCP II phalangeal cartilage was 389.6 {+-} 85.5 msec vs. 558.7 {+-} 74.4 msec in healthy subjects. The metacarpal MCP II cartilage dGEMRIC index was 357.3 msec {+-} 97.1 msec vs. 490.0 {+-} 86.6 msec. The dGEMRIC indices of MCP III were: phalangeal 436.2 {+-} 113.6 msec in RA, 558.8 {+-} 115.5 msec in healthy subjects and metacarpal 398.0 {+-} 97.6 msec in RA and 529.6 {+-} 111.0 msec in healthy subjects. Age and cartilage thickness were not significantly different. In PIP joints of finger osteoarthritis patients, low dGEMRIC indices were noted, compared to the controls. Conclusion: The dGEMRIC of finger joints is feasible in patients with RA and finger OA. Morphologically normal cartilage shows significantly decreased dGEMRIC values in RA, pointing towards cartilage degeneration on a molecular level. Further studies are needed to establish the usefulness of this technique for early diagnosis, prognosis and therapy monitoring. (orig.)

  13. Semi-automatic knee cartilage segmentation

    Science.gov (United States)

    Dam, Erik B.; Folkesson, Jenny; Pettersen, Paola C.; Christiansen, Claus

    2006-03-01

    Osteo-Arthritis (OA) is a very common age-related cause of pain and reduced range of motion. A central effect of OA is wear-down of the articular cartilage that otherwise ensures smooth joint motion. Quantification of the cartilage breakdown is central in monitoring disease progression and therefore cartilage segmentation is required. Recent advances allow automatic cartilage segmentation with high accuracy in most cases. However, the automatic methods still fail in some problematic cases. For clinical studies, even if a few failing cases will be averaged out in the overall results, this reduces the mean accuracy and precision and thereby necessitates larger/longer studies. Since the severe OA cases are often most problematic for the automatic methods, there is even a risk that the quantification will introduce a bias in the results. Therefore, interactive inspection and correction of these problematic cases is desirable. For diagnosis on individuals, this is even more crucial since the diagnosis will otherwise simply fail. We introduce and evaluate a semi-automatic cartilage segmentation method combining an automatic pre-segmentation with an interactive step that allows inspection and correction. The automatic step consists of voxel classification based on supervised learning. The interactive step combines a watershed transformation of the original scan with the posterior probability map from the classification step at sub-voxel precision. We evaluate the method for the task of segmenting the tibial cartilage sheet from low-field magnetic resonance imaging (MRI) of knees. The evaluation shows that the combined method allows accurate and highly reproducible correction of the segmentation of even the worst cases in approximately ten minutes of interaction.

  14. Repairing articular cartilage defects with tissue-engineering cartilage in rabbits

    Institute of Scientific and Technical Information of China (English)

    SONG Hong-xing; LI Fo-bao; SHEN Hui-liang; LIAO Wei-ming; LIU Miao; WANG Min; CAO Jun-ling

    2006-01-01

    Objective: To investigate the effect of cancellous bone matrix gelatin (BMG) engineered with allogeneic chondrocytes in repairing articular cartilage defects in rabbits.Methods: Chondrocytes were seeded onto three-dimensional cancellous BMG and cultured in vitro for 12 days to prepare BMG-chondrocyte complexes. Under anesthesia with 2.5% pentobarbital sodium (1 ml/kg body weight), articular cartilage defects were made on the right knee joints of 38 healthy New Zealand white rabbits (regardless of sex, aged 4-5 months and weighing 2.5-3 kg) and the defects were then treated with 2.5 % trypsin.Then BMG-chondrocyte complex (Group A, n=18 ),BMG ( Group B, n=10), and nothing ( Group C, n=10)were implanted into the cartilage defects, respectively. The repairing effects were assessed by macroscopic, histologic,transmission electron microscopic (TEM) observation,immunohistochemical examination and in situ hybridization detection, respectively, at 2, 4, 8, 12 and 24 weeks after operation.Results: Cancellous BMG was degraded within 8 weeks after operation. In Group A, lymphocyte infiltration was observed around the graft. At 24 weeks after operation, the cartilage defects were repaired by cartilage tissues and the articular cartilage and subchondral bone were soundly healed. Proteoglycan and type Ⅱ collagen were detected in the matrix of the repaired tissues by Safranin-O staining and immunohistochemical staining,respectively. In situ hybridization proved gene expression of type Ⅱ collagen in the cytoplasm of chondrocytes in the repaired tissues. TEM observation showed that chondrocytes and cartilage matrix in repaired tissues were almost same as those in the normal articular cartilage. In Group B, the defects were repaired by cartilage-fibrous tissues. In Group C, the defects were repaired only by fibrous tissues.Conclusions : Cancellous BMG can be regarded as the natural cell scaffolds for cartilage tissue engineering.Articular cartilage defects can be repaired by

  15. In vitro precultivation alleviates post-implantation inflammation and enhances development of tissue-engineered tubular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Luo Xusong; Zhou Guangdong; Liu Wei; Zhang Wenjie; Cui Lei; Cao Yilin [Department of Plastic and Reconstructive Surgery, Shanghai Key Laboratory of Tissue Engineering, Shanghai 9th People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Cen Lian, E-mail: guangdongzhou@126.co, E-mail: yilincao@yahoo.co [National Tissue Engineering Center of China, Shanghai 200011 (China)

    2009-04-15

    Tissue-engineered tubular cartilage is a promising graft for tracheal reconstruction. But polylactic acid/polyglycolic acid (PLA/PGA) fibers, the frequently used scaffolds for cartilage engineering, often elicit an obvious inflammation response following implantation into immunocompetent animals. We propose that the inflammation could be alleviated by in vitro precultivation. In this study, after in vitro culture for either 2 days (direct implantation group (DI)) or for 2 weeks (precultivation implantation group (PI)), autologous tubular chondrocyte-PLA/PGA constructs were subcutaneously implanted into rabbits. In the PI group, after 2 weeks of precultivation, most of the fibers were found to be completely embedded in an extracellular matrix (ECM) produced by the chondrocytes. Importantly, no obvious inflammatory reaction was observed after in vivo implantation and homogeneous cartilage-like tissue was formed with biomechanical properties close to native tracheal cartilage at 4 weeks post-implantation. In the DI group, however, an obvious inflammatory reaction was observed within and around the cell-scaffold constructs at 1 week implantation and only sporadic cartilage islands separated by fibrous tissue were observed at 4 weeks. These results demonstrated that the post-implantation inflammatory reaction could be alleviated by in vitro precultivation, which contributes to the formation of satisfactory tubular cartilage for tracheal reconstruction.

  16. Cartilage development requires the function of Estrogen-related receptor alpha that directly regulates sox9 expression in zebrafish.

    Science.gov (United States)

    Kim, Yong-Il; No Lee, Joon; Bhandari, Sushil; Nam, In-Koo; Yoo, Kyeong-Won; Kim, Se-Jin; Oh, Gi-Su; Kim, Hyung-Jin; So, Hong-Seob; Choe, Seong-Kyu; Park, Raekil

    2015-12-10

    Estrogen-related receptor alpha (ESRRa) regulates a number of cellular processes including development of bone and muscles. However, direct evidence regarding its involvement in cartilage development remains elusive. In this report, we establish an in vivo role of Esrra in cartilage development during embryogenesis in zebrafish. Gene expression analysis indicates that esrra is expressed in developing pharyngeal arches where genes necessary for cartilage development are also expressed. Loss of function analysis shows that knockdown of esrra impairs expression of genes including sox9, col2a1, sox5, sox6, runx2 and col10a1 thus induces abnormally formed cartilage in pharyngeal arches. Importantly, we identify putative ESRRa binding elements in upstream regions of sox9 to which ESRRa can directly bind, indicating that Esrra may directly regulate sox9 expression. Accordingly, ectopic expression of sox9 rescues defective formation of cartilage induced by the knockdown of esrra. Taken together, our results indicate for the first time that ESRRa is essential for cartilage development by regulating sox9 expression during vertebrate development.

  17. Preparation of Articular Cartilage Specimens for Scanning Electron Microscopy.

    Science.gov (United States)

    Stupina, T A

    2016-08-01

    We developed and adapted a technology for preparation of articular cartilage specimens for scanning electron microscopy. The method includes prefixation processing, fixation, washing, and dehydration of articular cartilage specimens with subsequent treatment in camphene and air-drying. The technological result consists in prevention of deformation of the articular cartilage structures. The method is simpler and cheaper than the known technologies. PMID:27591865

  18. A Novel Biodegradable Polyurethane Matrix for Auricular Cartilage Repair: An In Vitro and In Vivo Study.

    Science.gov (United States)

    Iyer, Kartik; Dearman, Bronwyn L; Wagstaff, Marcus J D; Greenwood, John E

    2016-01-01

    Auricular reconstruction poses a challenge for reconstructive and burns surgeons. Techniques involving cartilage tissue engineering have shown potential in recent years. A biodegradable polyurethane matrix developed for dermal reconstruction offers an alternative to autologous, allogeneic, or xenogeneic biologicals for cartilage reconstruction. This study assesses such a polyurethane matrix for this indication in vivo and in vitro. To evaluate intrinsic cartilage repair, three pigs underwent auricular surgery to create excisional cartilage ± perichondrial defects, measuring 2 × 3 cm in each ear, into which acellular polyurethane matrices were implanted. Biopsies were taken at day 28 for histological assessment. Porcine chondrocytes ± perichondrocytes were cultured and seeded in vitro onto 1 × 1 cm polyurethane scaffolds. The total culture period was 42 days; confocal, histological, and immunohistochemical analyses of scaffold cultures were performed on days 14, 28, and 42. In vivo, the polyurethane matrices integrated with granulation tissue filling all biopsy samples. Minimal neocartilage invasion was observed marginally on some samples. Tissue composition was identical between ears whether perichondrium was left intact, or not. In vitro, the polyurethane matrix was biocompatible with chondrocytes ± perichondrocytes and supported production of extracellular matrix and Type II collagen. No difference was observed between chondrocyte culture alone and chondrocyte/perichondrocyte scaffold coculture. The polyurethane matrix successfully integrated into the auricular defect and was a suitable scaffold in vitro for cartilage tissue engineering, demonstrating its potential application in auricular reconstruction. PMID:26284639

  19. Photodynamic damage to cartilage and synovial tissue grafted on a chick's chorioallantoic membrane

    Science.gov (United States)

    Fisher, M.; Nahir, A. M.; Kimel, Sol

    1997-09-01

    Rheumatoid arthritis (RA) is a chronic inflammatory disease of the synovial joints causing pain deformities and disability. The highly vascular inflamed synovium has aggressive and destructive characteristics, it invades, erodes and gradually destroys cartilage and underlying bone. Photodynamic therapy (PDT) was performed using the chick chorioallantoic membrane (CAM) model to investigate the vitality of synovium and cartilage implanted on the CAM. Synovium, obtained from human patients, was grafted onto the CAM; gross microscopy and histology proved its vitality 7 days post grafting. Cartilage obtained from rabbit knee joint was also maintained on the CAM for 7 days. Its vitality was demonstrated by histology and by measuring metabolic and enzymatic activity of cartilage cells (chondrocytes) as well as the collagen and proteoglycans content. Selective PDT was performed using aluminum phthalocyanine tetrasulfonate (AlPcS4), a hydrophilic compound, soluble in biological solutions, as a photosensitizer. After irradiation with a diode laser (lambda equals 670 nm, 10 mW) damage was observed in vascularized synovium grafts, whereas avascular cartilage remained intact.

  20. Holmium laser ablation of cartilage: effects of delivery fiber angle of incidence

    Science.gov (United States)

    Asshauer, Thomas; Oberthur, Thorsten; Jansen, Thomas; Gerber, Bruno E.; Delacretaz, Guy P.

    1996-01-01

    The effects of 2.12 micrometers Cr:Tm:Ho:YAG laser pulses delivered in isotonic saline solution via an optical fiber system on fresh porcine femur patellar groove cartilage were studied in vitro. Various irradiation geometry, corresponding to angles of 0 - 90 degree(s) of the delivering fiber with respect to the cartilage surface, have been investigated. A laser pulse energies of 1.0 J with a pulse duration of 250 microsecond(s) (FWHM) was used. The dynamics of the induced transient vapor bubbles and the ablation process were monitored by time resolved flash videography techniques. Acoustic transients of up to 200 bars induced by bubble collapses were measured by a calibrated piezoelectric needle probe hydrophone. Histological assessment of the irradiated cartilage samples was performed using azan and Safranin-O stains. The extent of the area of altered cartilage cells is larger than the zone of tissue matrix damage. The predominant mechanism of tissue damage is thermal rather than acousto-mechanical. Cartilage treatment at an angle of incidence of 30 degree(s) reduces significantly the overall damage as compared to 60 degree(s) or 90 degree(s) irradiation.

  1. Enhanced mechanical properties of thermosensitive chitosan hydrogel by silk fibers for cartilage tissue engineering.

    Science.gov (United States)

    Mirahmadi, Fereshteh; Tafazzoli-Shadpour, Mohammad; Shokrgozar, Mohammad Ali; Bonakdar, Shahin

    2013-12-01

    Articular cartilage has limited repair capability following traumatic injuries and current methods of treatment remain inefficient. Reconstructing cartilage provides a new way for cartilage repair and natural polymers are often used as scaffold because of their biocompatibility and biofunctionality. In this study, we added degummed chopped silk fibers and electrospun silk fibers to the thermosensitive chitosan/glycerophosphate hydrogels to reinforce two hydrogel constructs which were used as scaffold for hyaline cartilage regeneration. The gelation temperature and gelation time of hydrogel were analyzed by the rheometer and vial tilting method. Mechanical characterization was measured by uniaxial compression, indentation and dynamic mechanical analysis assay. Chondrocytes were then harvested from the knee joint of the New Zealand white rabbits and cultured in constructs. The cell proliferation, viability, production of glycosaminoglycans and collagen type II were assessed. The results showed that mechanical properties of the hydrogel were significantly enhanced when a hybrid with two layers of electrospun silk fibers was made. The results of GAG and collagen type II in cell-seeded scaffolds indicate support of the chondrogenic phenotype for chondrocytes with a significant increase in degummed silk fiber-hydrogel composite for GAG content and in two-layer electrospun fiber-hydrogel composite for Col II. It was concluded that these two modified scaffolds could be employed for cartilage tissue engineering.

  2. Prefabrication of 3D cartilage contructs: towards a tissue engineered auricle--a model tested in rabbits.

    Directory of Open Access Journals (Sweden)

    Achim von Bomhard

    Full Text Available The reconstruction of an auricle for congenital deformity or following trauma remains one of the greatest challenges in reconstructive surgery. Tissue-engineered (TE three-dimensional (3D cartilage constructs have proven to be a promising option, but problems remain with regard to cell vitality in large cell constructs. The supply of nutrients and oxygen is limited because cultured cartilage is not vascular integrated due to missing perichondrium. The consequence is necrosis and thus a loss of form stability. The micro-surgical implantation of an arteriovenous loop represents a reliable technology for neovascularization, and thus vascular integration, of three-dimensional (3D cultivated cell constructs. Auricular cartilage biopsies were obtained from 15 rabbits and seeded in 3D scaffolds made from polycaprolactone-based polyurethane in the shape and size of a human auricle. These cartilage cell constructs were implanted subcutaneously into a skin flap (15 × 8 cm and neovascularized by means of vascular loops implanted micro-surgically. They were then totally enhanced as 3D tissue and freely re-implanted in-situ through microsurgery. Neovascularization in the prefabricated flap and cultured cartilage construct was analyzed by microangiography. After explantation, the specimens were examined by histological and immunohistochemical methods. Cultivated 3D cartilage cell constructs with implanted vascular pedicle promoted the formation of engineered cartilaginous tissue within the scaffold in vivo. The auricles contained cartilage-specific extracellular matrix (ECM components, such as GAGs and collagen even in the center oft the constructs. In contrast, in cultivated 3D cartilage cell constructs without vascular pedicle, ECM distribution was only detectable on the surface compared to constructs with vascular pedicle. We demonstrated, that the 3D flaps could be freely transplanted. On a microangiographic level it was evident that all the skin flaps

  3. "Changes in cartilage of rats after treatment with Quinolone and in Magnesium-deficient diet "

    Directory of Open Access Journals (Sweden)

    Shakibaei M

    2002-07-01

    Full Text Available Ultrastructural changes in immature articular carilage were studied after treatment of 5-weeks-old rats with ofloxacin, a fluoroquinolone, and in magnesium deficiency.We concluded that quinolone-induced arthropathy is probably due to chelation of functionally available magnesium in joint cartilage as magnesium deficiency in joint cartilage could impair chondrocyte-matrix- interaction which is mediated by cation-dependent integrin-receptors of the β1-subfamily. With immuno-histochemical methods using monoclonal and polyclonal antibodies we showed that B1 integrins were expressed in rat joint cartilage. Joint cartilage lesions were detected in ofloxacin-treated and magnesium-deficient rats. Lesions were more pronounced in the quinolone-treated group. Expression of several integrins was reduced in the vicinity of lesions after oral treatment with 2×600 mg ofloxacin/kg body wt for one day. Gross-structural lesions (e.g. cleft formation, unmasked collagen fibres in magnesium deficient rats were very similar but changes in intergrin expression were less pronounced. Alterations observed on the ultrastructural level showed striking similarities in magnesium-deficient rats and in rats treated with single doses of 600 mg ofloxacin per kg body wt.Typical observation were: bundle shaped, electron-dense aggregates on the surface and in the cytoplasm of chondrocytes, detachement of the cell membrance from the matrix and necrotic chondrocytes, reduced synthesis and/or reduced of extracellular matrix and swelling of cell organelles such as mitochondria.The results of this study confirm our previously reported finding that quinolone-induced arthropathy probably is caued by a reduction of functionally available magnesium (ionized Mg2+ in cartilage. Furthermore, they provide a basis for aimed studies with human cartilage samples from quinolone-treated patients which might be available postmortal or after hip replacement surgery

  4. 2-D finite difference time domain model of ultrasound reflection from normal and osteoarthritic human articular cartilage surface.

    Science.gov (United States)

    Kaleva, Erna; Liukkonen, Jukka; Toyras, Juha; Saarakkala, Simo; Kiviranta, Panu; Jurvelin, Jukka

    2010-04-01

    Quantitative high-frequency ultrasonic evaluation of articular cartilage has shown a potential for the diagnosis of osteoarthritis, where the roughness of the surface, collagen and proteoglycan contents, and the density and mechanical properties of cartilage change concurrently. Experimentally, these factors are difficult to investigate individually and thus a numerical model is needed. The present study is the first one to use finite difference time domain modeling of pulse-echo measurements of articular cartilage. Ultrasound reflection from the surface was investigated with varying surface roughness, material parameters (Young's modulus, density, longitudinal, and transversal velocities) and inclination of the samples. The 2-D simulation results were compared with the results from experimental measurements of the same samples in an identical geometry. Both the roughness and the material parameters contributed significantly to the ultrasound reflection. The angular dependence of the ultrasound reflection was strong for a smooth cartilage surface but disappeared for the samples with a rougher surface. These results support the findings of previous experimental studies and indicate that ultrasound detects changes in the cartilage that are characteristic of osteoarthritis. In the present study there are differences between the results of the simulations and the experimental measurements. However, the systematic patterns in the experimental behavior are correctly reproduced by the model. In the future, our goal is to develop more realistic acoustic models incorporating inhomogeneity and anisotropy of the cartilage. PMID:20378451

  5. Aquaporin-1 and aquaporin-3 expressions in the temporomandibular joint condylar cartilage after an experimentally induced osteoarthritis

    Institute of Scientific and Technical Information of China (English)

    MENG Juan-hong; MA Xu-chen; LI Zhi-min; WU Deng-cheng

    2007-01-01

    Background Over 70% of the total tissue weight in the cartilage matrix consists of water,and the early-stage osteoarthritic cartilage is characterized by swelling.Water transport in the cartilage matrix and across the membranes of chondrocytes may be important in normal and pathological conditions of cartilage.The purpose of this study was to identify aquaporin-1 (AQP1) and aquaporin-3 (AQP3) expressions in the mandibular condylar cartilage after experimentally induced osteoarthritis(OA)in rats.Methods An experimental temporomandibular joint OA was induced by partial discectomy in rats.The pathological characteristics of the normal,early-stage,and late-stage osteoarthritic TMJ cartilages were verified by histological techniques.The AQP1 and AQP3 gene expressions in the normal and osteoarthritic cartilages were measured using quantitative real-time reverse-transcription PCR analysis.The cartilage sections were incubated in primary polyclonal antibodies to AQP3;immunofluorescent microscopy was used to examine the AQP3 expression shown by its protein level.Results The mRNA expression levels of AQP1 and AQP3,analyzed using quantitative PCR,revealed that AQP3 mRNA was highly up-regulated in the OA cartilage,which was considered significant.There was no notable difference in the expression of AQP1 mRNA between OA and normal controls.With the progressing of the OA,the localization of the AQP3 protein was quite different from that of the normal cartilage.Cormpared to the normal cartilage,the expressions of AQP3 protein were observed mainly in the proliferative zone and the upper mid-zone chondrocytes at the early-stage of OA,and were observed to appear frequently throughout the mid-and deep zone during the late-stage of OA.Conclusions The high expression of AQP3 mRNA in the OA cartilage and the different localization of the AQP3 protein suggest that it may play a particular role in OA pathogenesis.Further study of AQP3 function may provide new insight into the

  6. Measuring Jupiter's water abundance by Juno: the link between interior and formation models

    CERN Document Server

    Helled, Ravit

    2014-01-01

    The JUNO mission to Jupiter is planned to measure the water abundance in Jupiter's atmosphere below the cloud layer. This measurement is important because it can be used to reveal valuable information on Jupiter's origin and its composition. In this paper we discuss the importance of this measurement, the challenges in its interpretation, and address how it can be connected to interior and formation models of Jupiter.

  7. Comparison of the erbium-yttrium aluminum garnet and carbon dioxide lasers for in vitro bone and cartilage ablation

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, C.; van de Merwe, W.P.; Smith, M.; Reinisch, L. (Uniformed Services Univ. of the Health Sciences, Bethesda, MD (USA))

    1990-01-01

    The in vitro bone- and cartilage-ablation characteristics of the solid-state erbium:yttrium aluminum garnet laser were compared to those of the carbon dioxide laser. Ablations of fresh, frozen cadaver septal cartilage and maxillary sinus bone were performed using total energies between 1 and 6 J. Specimens were studied using hematoxylin and eosin stain and digitized, computer-assisted measurements of 35-mm photographs. Erbium-yttrium aluminum garnet-ablated bone averaged 5 microns of adjacent tissue thermal injury, compared with 67 microns with carbon dioxide-ablated bone. Erbium-yttrium aluminum garnet-ablated cartilage averaged 2 microns of adjacent tissue thermal injury, compared with 21 microns with the carbon dioxide-ablated cartilage. The tissue-ablation characteristics of the erbium-yttrium aluminum garnet laser are promising for future otolaryngologic applications.

  8. Measurement techniques for in situ stresses around underground constructions in a deep clay formation

    Directory of Open Access Journals (Sweden)

    Li X.L.

    2010-06-01

    Full Text Available Disposal in deep underground geological formations is internationally recognized as the most viable option for the long-term management of high-level radioactive waste. In Belgium, the Boom clay formation is extensively studied in this context, in particular at the 225 m deep HADES Underground Research Facility in Mol. A cost-effective design of deep underground structures requires an accurate assessment of the in situ stresses; a good estimation of these stresses is also essential when interpreting in situ experiments regarding the hydro-mechanical behaviour of the host formation. Different measurement techniques are available to provide data on the stress evolution and other mechanical properties of the geological formation. The measurement can be direct (measurement of total pressure, or it can be an indirect technique, deriving the stress from related quantities such as strain (changes in structural members. Most total stress measurements are performed through permanently installed sensors; also once-only measurements are performed through specific methods (e.g. pressuremeter. Direct measurement of the stress state is challenging due to the complex mechanical behaviour of the clay, and the fact that the sensor installation inevitably disturbs the original stress field. This paper describes ways to deal with these problems and presents the results obtained using different techniques at HADES.

  9. A biomimetic three-dimensional woven composite scaffold for functional tissue engineering of cartilage

    Science.gov (United States)

    Moutos, Franklin T.; Freed, Lisa E.; Guilak, Farshid

    2007-02-01

    Tissue engineering seeks to repair or regenerate tissues through combinations of implanted cells, biomaterial scaffolds and biologically active molecules. The rapid restoration of tissue biomechanical function remains an important challenge, emphasizing the need to replicate structural and mechanical properties using novel scaffold designs. Here we present a microscale 3D weaving technique to generate anisotropic 3D woven structures as the basis for novel composite scaffolds that are consolidated with a chondrocyte-hydrogel mixture into cartilage tissue constructs. Composite scaffolds show mechanical properties of the same order of magnitude as values for native articular cartilage, as measured by compressive, tensile and shear testing. Moreover, our findings showed that porous composite scaffolds could be engineered with initial properties that reproduce the anisotropy, viscoelasticity and tension-compression nonlinearity of native articular cartilage. Such scaffolds uniquely combine the potential for load-bearing immediately after implantation in vivo with biological support for cell-based tissue regeneration without requiring cultivation in vitro.

  10. UVOT Measurements of Dust and Star Formation in the SMC and M33

    CERN Document Server

    Hagen, Lea M Z; Gronwall, Caryl A; Hoversten, Erik A; Vargas, Angelica; Immler, Stefan

    2015-01-01

    When measuring star formation rates using ultraviolet light, correcting for dust extinction is a critical step. However, with the variety of dust extinction curves to choose from, the extinction correction is quite uncertain. Here, we use Swift/UVOT to measure the extinction curve for star-forming regions in the SMC and M33. We find that both the slope of the curve and the strength of the 2175 Angstrom bump vary across both galaxies. In addition, as part of our modeling, we derive a detailed recent star formation history for each galaxy.

  11. Highly nonlinear stress-relaxation response of articular cartilage in indentation: Importance of collagen nonlinearity.

    Science.gov (United States)

    Mäkelä, J T A; Korhonen, R K

    2016-06-14

    Modern fibril-reinforced computational models of articular cartilage can include inhomogeneous tissue composition and structure, and nonlinear mechanical behavior of collagen, proteoglycans and fluid. These models can capture well experimental single step creep and stress-relaxation tests or measurements under small strains in unconfined and confined compression. Yet, it is known that in indentation, especially at high strain velocities, cartilage can express highly nonlinear response. Different fibril reinforced poroelastic and poroviscoelastic models were used to assess measured highly nonlinear stress-relaxation response of rabbit articular cartilage in indentation. Experimentally measured depth-dependent volume fractions of different tissue constituents and their mechanical nonlinearities were taken into account in the models. In particular, the collagen fibril network was modeled using eight separate models that implemented five different constitutive equations to describe the nonlinearity. These consisted of linear elastic, nonlinear viscoelastic and multiple nonlinear elastic representations. The model incorporating the most nonlinearly increasing Young׳s modulus of collagen fibrils as a function of strain captured best the experimental data. Relative difference between the model and experiment was ~3%. Surprisingly, the difference in the peak forces between the experiment and the model with viscoelastic collagen fibrils was almost 20%. Implementation of the measured volume fractions did not improve the ability of the model to capture the measured mechanical data. These results suggest that a highly nonlinear formulation for collagen fibrils is needed to replicate multi-step stress-relaxation response of rabbit articular cartilage in indentation with high strain rates. PMID:27130474

  12. Highly nonlinear stress-relaxation response of articular cartilage in indentation: Importance of collagen nonlinearity.

    Science.gov (United States)

    Mäkelä, J T A; Korhonen, R K

    2016-06-14

    Modern fibril-reinforced computational models of articular cartilage can include inhomogeneous tissue composition and structure, and nonlinear mechanical behavior of collagen, proteoglycans and fluid. These models can capture well experimental single step creep and stress-relaxation tests or measurements under small strains in unconfined and confined compression. Yet, it is known that in indentation, especially at high strain velocities, cartilage can express highly nonlinear response. Different fibril reinforced poroelastic and poroviscoelastic models were used to assess measured highly nonlinear stress-relaxation response of rabbit articular cartilage in indentation. Experimentally measured depth-dependent volume fractions of different tissue constituents and their mechanical nonlinearities were taken into account in the models. In particular, the collagen fibril network was modeled using eight separate models that implemented five different constitutive equations to describe the nonlinearity. These consisted of linear elastic, nonlinear viscoelastic and multiple nonlinear elastic representations. The model incorporating the most nonlinearly increasing Young׳s modulus of collagen fibrils as a function of strain captured best the experimental data. Relative difference between the model and experiment was ~3%. Surprisingly, the difference in the peak forces between the experiment and the model with viscoelastic collagen fibrils was almost 20%. Implementation of the measured volume fractions did not improve the ability of the model to capture the measured mechanical data. These results suggest that a highly nonlinear formulation for collagen fibrils is needed to replicate multi-step stress-relaxation response of rabbit articular cartilage in indentation with high strain rates.

  13. Characterization of human primary chondrocytes of osteoarthritic cartilage at varying severity

    Institute of Scientific and Technical Information of China (English)

    YIN Jing; YANG Zheng; CAO Yong-ping; GE Zi-gang

    2011-01-01

    Background There is a difficulty in evaluating the in vivo functionality of individual chondrocytes,and there is much heterogeneity among cartilage affected by osteoarthritis (OA).In this study,in vitro cultured chondrocytes harvested from varying stages of degeneration were studied as a projective model to further understand the pathogenesis of osteoarthritis.Methods Cartilage of varying degeneration of end-stage OA was harvested,while cell yield and matrix glycosaminoglycan (GAG) content were measured.Cell morphology,proliferation,and gene expression of collagen type Ⅰ,Ⅱ,and Ⅹ,aggrecan,matrix metalloproteinase 13 (MMP-13),and ADAMTS5 of the acquired chondrocytes were measured during subsequent in vitro culture.Results Both the number of cells and the GAG content increased with increasing severity of OA.Cell spreading area increased and gradually showed spindle-like morphology during in vitro culture.Gene expression of collagen type Ⅱ,collagen type X as well as GAG decreased with severity of cartilage degeneration,while expression of collagen type Ⅰ increased.Expression of MMP-13 increased with severity of cartilage degeneration,while expression of ADAMTS-5 remained stable.Expression of collagen type Ⅱ,X,GAG,and MMP-13 substantially decreased with in vitro culture.Expression of collagen type Ⅰ increased with in vitro cultures,while expression of ADAMTS 5 remained stable.Conclusions Expression of functional genes such as collagen type Ⅱ and GAG decreased during severe degeneration of OA cartilage and in vitro dedifferentiation.Gene expression of collagen Ⅰ and MMP-13 increased with severity of cartilage degeneration.

  14. Quantifying the lubricity of mechanically tough polyvinyl alcohol hydrogels for cartilage repair.

    Science.gov (United States)

    Ling, Doris; Bodugoz-Senturk, Hatice; Nanda, Salil; Braithwaite, Gavin; Muratoglu, Orhun K

    2015-12-01

    Polyvinyl alcohol hydrogels are biocompatible and can be used as synthetic articular cartilage. Their mechanical characteristics can be tailored by various techniques such as annealing or blending with other hydrophilic polymers. In this study, we quantified the coefficient of friction of various candidate polyvinyl alcohol hydrogels against cobalt-chrome alloy or swine cartilage using a new rheometer-based method. We investigated the coefficient of friction of polyvinyl alcohol-only hydrogels and blends with polyethylene glycol, polyacrylic acid, and polyacrylamide against swine cartilage and polished cobalt-chrome surfaces. The addition of the functional groups to polyvinyl alcohol, such as acrylamide (semi-interpenetrating network) and acrylic acid (blend), significantly reduced the coefficient of friction. The coefficient of friction of the polyvinyl alcohol-only hydrogel was measured as 0.4 ± 0.03 against cobalt-chrome alloy, and 0.09 ± 0.004 against cartilage, while those measurements for the polyvinyl alcohol-polyacrylic acid blends and polyvinyl alcohol-polyacrylamide semi-interpenetrating network were 0.07 ± 0.01 and 0.1 ± 0.003 against cobalt-chrome alloy, and 0.03 ± 0.001 and 0.02 ± 0.001 against cartilage, respectively. There was no significant or minimal difference in the coefficient of friction between samples from different regions of the knee, or animals, or when the cartilage samples were frozen for 1 day or 2 days before testing. However, changing lubricant from deionized water to ionic media, for example, saline or simulated body fluid, increased the coefficient of friction significantly. PMID:26614798

  15. Advanced Strategies for Articular Cartilage Defect Repair

    Directory of Open Access Journals (Sweden)

    Fergal J. O'Brien

    2013-02-01

    Full Text Available Articular cartilage is a unique tissue owing to its ability to withstand repetitive compressive stress throughout an individual’s lifetime. However, its major limitation is the inability to heal even the most minor injuries. There still remains an inherent lack of strategies that stimulate hyaline-like articular cartilage growth with appropriate functional properties. Recent scientific advances in tissue engineering have made significant steps towards development of constructs for articular cartilage repair. In particular, research has shown the potential of biomaterial physico-chemical properties significantly influencing the proliferation, differentiation and matrix deposition by progenitor cells. Accordingly, this highlights the potential of using such properties to direct the lineage towards which such cells follow. Moreover, the use of soluble growth factors to enhance the bioactivity and regenerative capacity of biomaterials has recently been adopted by researchers in the field of tissue engineering. In addition, gene therapy is a growing area that has found noteworthy use in tissue engineering partly due to the potential to overcome some drawbacks associated with current growth factor delivery systems. In this context, such advanced strategies in biomaterial science, cell-based and growth factor-based therapies that have been employed in the restoration and repair of damaged articular cartilage will be the focus of this review article.

  16. PRP and Articular Cartilage: A Clinical Update

    Science.gov (United States)

    Rossi, Roberto; Castoldi, Filippo; Michielon, Gianni

    2015-01-01

    The convincing background of the recent studies, investigating the different potentials of platelet-rich plasma, offers the clinician an appealing alternative for the treatment of cartilage lesions and osteoarthritis. Recent evidences in literature have shown that PRP may be helpful both as an adjuvant for surgical treatment of cartilage defects and as a therapeutic tool by intra-articular injection in patients affected by osteoarthritis. In this review, the authors introduce the trophic and anti-inflammatory properties of PRP and the different products of the available platelet concentrates. Then, in a complex scenario made of a great number of clinical variables, they resume the current literature on the PRP applications in cartilage surgery as well as the use of intra-articular PRP injections for the conservative treatment of cartilage degenerative lesions and osteoarthritis in humans, available as both case series and comparative studies. The result of this review confirms the fascinating biological role of PRP, although many aspects yet remain to be clarified and the use of PRP in a clinical setting has to be considered still exploratory. PMID:26075244

  17. Oxygen, nitric oxide and articular cartilage

    Directory of Open Access Journals (Sweden)

    B Fermor

    2007-04-01

    Full Text Available Molecular oxygen is required for the production of nitric oxide (NO, a pro-inflammatory mediator that is associated with osteoarthritis and rheumatoid arthritis. To date there has been little consideration of the role of oxygen tension in the regulation of nitric oxide production associated with arthritis. Oxygen tension may be particularly relevant to articular cartilage since it is avascular and therefore exists at a reduced oxygen tension. The superficial zone exists at approximately 6% O2, while the deep zone exists at less than 1% O2. Furthermore, oxygen tension can alter matrix synthesis, and the material properties of articular cartilage in vitro.The increase in nitric oxide associated with arthritis can be caused by pro-inflammatory cytokines and mechanical stress. Oxygen tension significantly alters endogenous NO production in articular cartilage, as well as the stimulation of NO in response to both mechanical loading and pro-inflammatory cytokines. Mechanical loading and pro-inflammatory cytokines also increase the production of prostaglandin E2 (PGE2. There is a complex interaction between NO and PGE2, and oxygen tension can alter this interaction. These findings suggest that the relatively low levels of oxygen within the joint may have significant influences on the metabolic activity, and inflammatory response of cartilage as compared to ambient levels. A better understanding of the role of oxygen in the production of inflammatory mediators in response to mechanical loading, or pro-inflammatory cytokines, may aid in the development of strategies for therapeutic intervention in arthritis.

  18. Birth injuries to the epiphyseal cartilage

    International Nuclear Information System (INIS)

    A birth injury in the vicinity of a joint might lead to a fracture through the epiphyseal cartilage. The criteria for diagnosing such a fracture at radiography are considered and the continued remodelling of the bone demonstrated. The history of 2 cases with late diagnosis and serious long-term sequelae are described, in order to emphasize the necessity of early radiography. (Auth.)

  19. Nonspecific otalgia: Indication for cartilage tympanoplasty

    Directory of Open Access Journals (Sweden)

    Rauf Ahmad

    2015-01-01

    Full Text Available Introduction: Myringoplasty and tympanoplasty are commonly performed otologic surgical procedures. The aim of this study was to analyze the influence of nonspecific otalgia on the successful autologous conchal cartilage and temporalis fascia graft take up in type-1 tympanoplasty. Materials and Methods: A total of 250 adult patients who met the inclusion criteria were enrolled for this study. Patients were placed in two groups (otalgia and nonotalgia group depending upon the history of otalgia. Patients in both groups were operated (type-1 tympanoplasty using randomly either temporalis fascia or conchal cartilage as the graft material. Follow-up of patients was done after 3 weeks, 6 weeks, and 3 months of surgery to check the status of graft take up. Result: Our study shows that patients in otalgia group in which autologous temporalis fascia was used as the graft material, the majority of patients had graft necrosis by 3 months after surgery (9.6% success only. Whereas patients of the same group in which autologous conchal cartilage was used as the graft material, successful graft take up was in 93.5% patients after 3 months of surgery. Our study shows that there was not much difference in using autologous temporalis fascia or autologous conchal cartilage on successful graft take up in nonotolgia group of patients, with success rate of 97.89% and 97.84%, respectively.

  20. Spatially resolved elemental distributions in articular cartilage

    Science.gov (United States)

    Reinert, T.; Reibetanz, U.; Vogt, J.; Butz, T.; Werner, A.; Gründer, W.

    2001-07-01

    In this study, the nuclear microprobe technique is employed to analyse the chemistry of joint cartilage in order to correlate internal structures of the collagen network with the elemental distribution. The samples were taken from pig's knee joint. 30 μm thick coronar cross-sections were prepared by means of cryosectioning and freeze-drying. We performed simultaneously particle induced X-ray emission (PIXE), Rutherford backscattering spectrometry (RBS) and elastic recoil detection analysis (ERDA). Thus we obtained spatially resolved distributions of the elements H, C, N, O, P, S, Cl, K and Ca. The main components of the organic matrix are H, C, N and O. It was shown that their relations vary with the cartilage structures. It could be shown that zones with aligned collagen fibrils contain less sulphur and potassium but more chlorine. The higher chlorine concentration is remarkable because newest biochemical studies found that hypochloric acid is involved in cartilage degradation. Furthermore, the calcium distribution is still of great interest. Its correlation to structural changes inside the cartilage is still being discussed. It could be disproved that zones of higher calcium concentration are related to the aligned structures of the collagen network.

  1. MULTIPLE OSSIFIED COSTAL CARTILAGES FOR 1ST RIB

    Directory of Open Access Journals (Sweden)

    Raghavendra D.R.

    2014-12-01

    Full Text Available Costal cartilages are flattened bars of hyaline cartilages. All ribs except the last two, join with the sternum through their respective costal cartilages directly or indirectly. During dissection for 1st MBBS students in the Department of Anatomy, JJMMC, Davangere, variation was found in a male cadaver aged 45 –50 years. Multiple ossified costal cartilages for 1st rib were present on left side. There were 3 costal cartilages connecting 1st rib to manubrium. There were two small intercostal spaces between them. The lower two small costal cartilages fused together to form a common segment which in turn fused with large upper costal cartilage. The large upper costal cartilage forms costochondral joint with 1st rib. All costal cartilages showed features of calcification. The present variation of multiple ossified costal cartilages are due to bifurcation of costal cartilage. It may cause musculoskeletal pain, intercostal nerve entrapment or vascular compression. Awareness of these anomalies are important for radiologists for diagnostic purpose and for surgeons for performing various clinical and surgical procedures.

  2. Measuring the rates of spontaneous vortex formation in highly oblate Bose-Einstein condensates

    Science.gov (United States)

    Neely, Tyler; Samson, Edward; Bradley, Ashton; Davis, Matthew; Anderson, Brian

    2009-05-01

    By studying the dynamics of the Bose-Einstein condensation transition in highly oblate (˜11:1 aspect ratio) traps, we have measured the dependence of spontaneous vortex formation on BEC growth rate, extending our previous experimental and numerical observations of spontaneous vortex formation in weakly oblate (˜2:1 aspect ratio) traps [1]. Our condensation procedure in these highly oblate traps allows us to create BECs over a large range of growth times, from approximately 200 ms to over 2 s. By characterizing vortex formation vs. BEC growth rate, and comparing experimental and numerical results, the Kibble-Zurek mechanism for topological defect formation may be quantitatively studied in our system. [1] C.N. Weiler, T.W. Neely, D.R. Scherer, A.S. Bradley, M.J. Davis, and B.P. Anderson., Nature 455, 948 (2008).

  3. Measurements of gas hydrate formation probability distributions on a quasi-free water droplet

    Science.gov (United States)

    Maeda, Nobuo

    2014-06-01

    A High Pressure Automated Lag Time Apparatus (HP-ALTA) can measure gas hydrate formation probability distributions from water in a glass sample cell. In an HP-ALTA gas hydrate formation originates near the edges of the sample cell and gas hydrate films subsequently grow across the water-guest gas interface. It would ideally be desirable to be able to measure gas hydrate formation probability distributions of a single water droplet or mist that is freely levitating in a guest gas, but this is technically challenging. The next best option is to let a water droplet sit on top of a denser, immiscible, inert, and wall-wetting hydrophobic liquid to avoid contact of a water droplet with the solid walls. Here we report the development of a second generation HP-ALTA which can measure gas hydrate formation probability distributions of a water droplet which sits on a perfluorocarbon oil in a container that is coated with 1H,1H,2H,2H-Perfluorodecyltriethoxysilane. It was found that the gas hydrate formation probability distributions of such a quasi-free water droplet were significantly lower than those of water in a glass sample cell.

  4. Compensation effect analysis in DIE method for through-casing measuring formation resistivity

    Science.gov (United States)

    Qing, Chen; Pardo, David; Hong-bin, Li; Fu-rong, Wang

    2011-08-01

    The measuring technique based on Double-Injection-Electrodes (DIE) and its compensation arithmetic method have been proven to be very useful for eliminating the errors caused by electrode-scale mechanical tolerances in formation resistivity measurement through metal case. In this paper, we found that even minor casing joint or casing corrosion may deteriorate the measurement accuracy. Based on theoretical analysis and self-adaptive goal oriented hp-Finite Element (FE) simulations, the compensation effects of DIE measurement technique were estimated. The calculated results from this measuring method are always close to the real formation resistivity, regardless of whether the metal casing is ideal or not. Meanwhile, large errors occur when recording measurements based on Single-Injection-Electrodes (SIE), since the calculated formation resistivity may provide negative values when casing joint or casing corrosion exists. The Double-Injection-Electrode (DIE) measurement technique is predicted to have good compensation effects in many non-ideal situations with uneven metal casing besides electrode-scale mechanical tolerances.

  5. Ultrasonographic evaluation of the femoral cartilage thickness in patients with hypothyroidism.

    Science.gov (United States)

    Devrimsel, Gul; Beyazal, Munevver Serdaroglu; Turkyilmaz, Aysegul Kucukali; Sahin, Serap Baydur

    2016-08-01

    [Purpose] The aim of this study was to investigate the effects of hypothyroidism on femoral cartilage thickness by using ultrasound, which has been found to be useful in the early diagnosis of knee osteoarthritis. [Subjects and Methods] Forty patients diagnosed with hypothyroidism and 30 age-, gender-, smoking status, physical activity-, and body mass index-matched healthy subjects were enrolled. The thickness of the femoral articular cartilage was measured using a 7- to 12-MHz linear probe. Three mid-point measurements were taken from each knee at the lateral condyle, intercondylar area, and medial condyle. [Results] Age, gender, body mass index, smoking status, and physical activity were similar between the groups, but patients with hypothyroidism had thinner femoral cartilage than the healthy controls at all measurement sites. Nonetheless, the differences were not statistically significant (except in the case of the left medial condyle). [Conclusion] Ultrasonographic measurement of femoral cartilage thickness may be useful in the early diagnosis of knee osteoarthritis in patients with hypothyroidism. PMID:27630407

  6. Proteolytic degradation of the collagen network results in cartilage with inferior biomechanical properties

    NARCIS (Netherlands)

    Bank, R.A.; Koppele, J.M. te

    1999-01-01

    Swelling of cartilage, one of the early signs of osteoarthritis (OA), is considered to be the result of a collagen network that has lost its integrity. So far, no quantitative data directly support this assertion: combined measurements of the state of the collagen network per se and the degree of sw

  7. Regeneration of Articular Cartilage in Lizard Knee from Resident Stem/Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Lorenzo Alibardi

    2015-09-01

    Full Text Available The epiphysis of femur and tibia in the lizard Podarcis muralis can extensively regenerate after injury. The process involves the articular cartilage and metaphyseal (growth plate after damage. The secondary ossification center present between the articular cartilage and the growth plate is replaced by cartilaginous epiphyses after about one month of regeneration at high temperature. The present study analyzes the origin of the chondrogenic cells from putative stem cells located in the growing centers of the epiphyses. The study is carried out using immunocytochemistry for the detection of 5BrdU-labeled long retaining cells and for the localization of telomerase, an enzyme that indicates stemness. The observations show that putative stem cells retaining 5BrdU and positive for telomerase are present in the superficial articular cartilage and metaphyseal growth plate located in the epiphyses. This observation suggests that these areas represent stem cell niches lasting for most of the lifetime of lizards. In healthy long bones of adult lizards, the addition of new chondrocytes from the stem cells population in the articular cartilage and the metaphyseal growth plate likely allows for slow, continuous longitudinal growth. When the knee is injured in the adult lizard, new populations of chondrocytes actively producing chondroitin sulfate proteoglycan are derived from these stem cells to allow for the formation of completely new cartilaginous epiphyses, possibly anticipating the re-formation of secondary centers in later stages. The study suggests that in this lizard species, the regenerative ability of the epiphyses is a pre-adaptation to the regeneration of the articular cartilage.

  8. Arthrosonography and biomarkers in the evaluation of destructive knee cartilage osteoarthrosis

    Directory of Open Access Journals (Sweden)

    Živanović Sandra

    2009-01-01

    Full Text Available Introduction. Knee osteoarthrosis (OA is a degenerative disease with progressive loss of cartilage of joints and bone destruction. During this process, the release of fragments of connective tissue matrix is detected in the biological fluids such as human cartilage glycoprotein (YKL-40, cartilage oligomeric matrix protein (COMP and collagen type I C terminal telopeptid (CTX-I. Objective. The aim of the study was to determine the degree of connection cartilage thickness measured by ultrasound with serum concentrations of biomarkers YKL-40, COMP and CTX-I in patients with primary knee OA. Methods. The analysis included 88 patients with the diagnosis of knee OA. Ultrasound examination of knees were done by two rheumatologists. The analysis of serum samples determined the concentration of COMP, YKL-40 and CTX-I by the ELISA method. Results. The average age of patients was 69.97±9.37 years and the duration of knee OA 6.46±6.73 years. The average cartilage thickness of the femoral condyle was 1.33±0.20 mm; of the medial condyle (MC (front access 1.30±0.23 mm, (rear access 1.30±0.29 mm and lateral condyli (LC (front access 1.39±0.27 mm. The average cartilage thickness of MC (front access was 1.27 mm (0.98-1.42 mm, (rear access 1.27 mm (0.84-1.46 mm and LC (front access 1.36 mm (1.01-1.57 mm (p=0.002. There was a significant connection in the negative direction between the patients' age and the cartilage thickness of MC (front and rear access and LC (front access (r=-0.253; p=0.017. There was a significant negative direction of interrelationship between the cartilage thickness of MC (front access (r=-0.259; p=0.015 and LC (front access and the disease duration (r=-0.259; p=0.015. In patients with knee OA lasting for 5 years the measured cartilage thickness was 1.27 mm (1.16-1.49 mm, and 0.99 mm (0.94-1.23 mm (p=0.007 in those lasting for 20 years. There was a significant relationship in a negative direction between the concentration of YKL-40 and

  9. In situ recording of particle network formation in liquids by ion conductivity measurements.

    Science.gov (United States)

    Pfaffenhuber, Christian; Sörgel, Seniz; Weichert, Katja; Bele, Marjan; Mundinger, Tabea; Göbel, Marcus; Maier, Joachim

    2011-09-21

    The formation of fractal silica networks from a colloidal initial state was followed in situ by ion conductivity measurements. The underlying effect is a high interfacial lithium ion conductivity arising when silica particles are brought into contact with Li salt-containing liquid electrolytes. The experimental results were modeled using Monte Carlo simulations and tested using confocal fluorescence laser microscopy and ζ-potential measurements.

  10. Time-resolved electrochemical measurement device for microscopic liquid interface during droplet formation

    NARCIS (Netherlands)

    Fukuyama, Mao; Yoshida, Yumi; Eijkel, Jan C.T.; Berg, van den Albert; Hibara, Akihide

    2013-01-01

    An electrochemical measurement system with a high-speed camera for observation of dynamic behavior of ionic molecules at a water-in-oil interface during microfluidic droplet formation is described. In order to demonstrate the usefulness of the system, a liquid interface between 1 M sodium chloride a

  11. Chondrocyte differentiation for auricular cartilage reconstruction using a chitosan based hydrogel.

    Science.gov (United States)

    García-López, J; Garciadiego-Cázares, D; Melgarejo-Ramírez, Y; Sánchez-Sánchez, R; Solís-Arrieta, L; García-Carvajal, Z; Sánchez-Betancourt, J I; Ibarra, C; Luna-Bárcenas, G; Velasquillo, C

    2015-12-01

    Tissue engineering with the use of biodegradable and biocompatible scaffolds is an interesting option for ear repair. Chitosan-Polyvinyl alcohol-Epichlorohydrine hydrogel (CS-PVA-ECH) is biocompatible and displays appropriate mechanical properties to be used as a scaffold. The present work, studies the potential of CS-PVA-ECH scaffolds seeded with chondrocytes to develop elastic cartilage engineered-neotissues. Chondrocytes isolated from rabbit and swine elastic cartilage were independently cultured onto CS-PVA-ECH scaffolds for 20 days to form the appropriate constructs. Then, in vitro cell viability and morphology were evaluated by calcein AM and EthD-1 assays and Scanning Electron Microscopy (SEM) respectively, and the constructs were implanted in nu/nu mice for four months, in order to evaluate the neotissue formation. Histological analysis of the formed neotissues was performed by Safranin O, Toluidine blue (GAG's), Verhoeff-Van Gieson (elastic fibers), Masson's trichrome (collagen) and Von Kossa (Calcium salts) stains and SEM. Results indicate appropriate cell viability, seeded with rabbit or swine chondrocyte constructs; nevertheless, upon implantation the constructs developed neotissues with different characteristics depending on the animal species from which the seeded chondrocytes came from. Neotissues developed from swine chondrocytes were similar to auricular cartilage, while neotissues from rabbit chondrocytes were similar to hyaline cartilage and eventually they differentiate to bone. This result suggests that neotissue characteristics may be influenced by the animal species source of the chondrocytes isolated. PMID:26119536

  12. Multilayered Short Peptide-Alginate Blends as New Materials for Potential Applications in Cartilage Tissue Regeneration.

    Science.gov (United States)

    Knoll, Grant A; Romanelli, Steven M; Brown, Alexandra M; Sortino, Rachel M; Banerjee, Ipsita A

    2016-03-01

    Peptide based nanomaterials have been gaining increased prominence due to their ability to form permeable scaffolds that promote growth and regeneration of new tissue. In this work for the first time a short hexapeptide motif VQIVYK, derived from the Tau protein family was conjugated with an organic polyamine linker, putrescine and utilized as a template for developing new materials for cartilage tissue regeneration. Our results showed that the conjugate formed extensive nanofibrous assemblies upon self-assembly under aqueous conditions. We then employed the layer-by-layer (LBL) approach to design the scaffold by first incorporating a short segment of the dentin sialophosphoprotein motif GDASYNSDESK followed by integration with the peptide sequence GSGAGAGSGAGAGSGAGA. This sequence mimics Ala, Gly, Ser repeats seen in the spider silk protein. We then incorporated the polysaccharide alginate which served as a hydrogel. To further enhance binding interactions with chondrocytes, and promote the formation of cartilage in vitro, the bionanocomposites were then attached to the chondrocyte binding peptide sequence HDSQLEALIKFM. The thermal properties as well as biodegradability of the scaffold was examined. To confirm biocompatibility, we examined cell viability, attachment and morphology in the presence of bovine chondrocytes. The cells were found to efficiently adhere to the scaffolds which formed an intricate mesh mimicking the extracellular matrix of cartilage tissue. To evaluate if differentiation occurred in the presence of the scaffolds, we examined in vitro deposition of proteoglycans. Thus, we have developed a new family of nanoscale scaffolds that may be utilized for cartilage tissue regeneration.

  13. Differentiating the extent of cartilage repair in rabbit ears using nonlinear optical microscopy.

    Science.gov (United States)

    Zhu, X Q; Xu, Y H; Liao, C X; Liu, W G; Cheng, K K; Chen, J X

    2015-11-01

    Nonlinear optical microscopy (NLOM) was used as a noninvasive and label-free tool to detect and quantify the extent of the cartilage recovery. Two cartilage injury models were established in the outer ears of rabbits that created a different extent of cartilage recovery based on the presence or absence of the perichondrium. High-resolution NLOM images were used to measure cartilage repair, specifically through spectral analysis and image texture. In contrast to a wound lacking a perichondrium, wounds with intact perichondria demonstrated significantly larger TPEF signals from cells and matrix, coarser texture indicating the more deposition of type I collagen. Spectral analysis of cells and matrix can reveal the matrix properties and cell growth. In addition, texture analysis of NLOM images showed significant differences in the distribution of cells and matrix of repaired tissues with or without perichondrium. Specifically, the decay length of autocorrelation coefficient based on TPEF images is 11.2 ± 1.1 in Wound 2 (with perichondrium) and 7.5 ± 2.0 in Wound 1 (without perichondrium), indicating coarser image texture and faster growth of cells in repaired tissues with perichondrium (p < 0.05). Moreover, the decay length of autocorrelation coefficient based on collagen SHG images also showed significant difference between Wound 2 and 1 (16.2 ± 1.2 vs. 12.2 ± 2.1, p < 0.05), indicating coarser image texture and faster deposition of collagen in repaired tissues with perichondrium (Wound 2). These findings suggest that NLOM is an ideal tool for studying cartilage repair, with potential applications in clinical medicine. NLOM can capture macromolecular details and distinguish between different extents of cartilage repair without the need for labelling agents.

  14. Measuring star formation with resolved observations: the test case of M33

    CERN Document Server

    Boquien, M; Aalto, S; Boselli, A; Braine, J; Buat, V; Combes, F; Israel, F; Kramer, C; Lord, S; Relano, M; Rosolowsky, E; Stacey, G; Tabatabaei, F; van der Tak, F; van der Werf, P; Verley, S; Xilouris, M

    2015-01-01

    Context. Measuring star formation at a local scale is important to constrain star formation laws. Yet, it is not clear whether and how the measure of star formation is affected by the spatial scale at which a galaxy is observed. Aims. We want to understand the impact of the resolution on the determination of the spatially resolved star formation rate (SFR) and other directly associated physical parameters such as the attenuation. Methods. We have carried out a multi-scale, pixel-by-pixel study of the nearby galaxy M33. Assembling FUV, Halpha, 8, 24, 70, and 100 micron maps, we have systematically compared the emission in individual bands with various SFR estimators from a resolution of 33 pc to 2084 pc. Results. We have found that there are strong, scale-dependent, discrepancies up to a factor 3 between monochromatic SFR estimators and Halpha+24 micron. The scaling factors between individual IR bands and the SFR show a strong dependence on the spatial scale and on the intensity of star formation. Finally, str...

  15. Glenohumeral relationships: subchondral mineralization patterns, thickness of cartilage, and radii of curvature.

    Science.gov (United States)

    Zumstein, Valentin; Kraljević, Marko; Müller-Gerbl, Magdalena

    2013-11-01

    Subchondral mineralization represents the loading history of a joint and can be measured in vivo using computed tomography osteoabsorptiometry. Different mineralization patterns in the glenohumeral joint have been explained by the principle of physiologic incongruence. We sought to support this explanation by measurement of mineralization, radii, and cartilage thickness in 18 fresh shoulder specimens. We found three mineralization patterns: bicentric, monocentric anterior, and monocentric central. Mean radii of the glenoids were 27.4 mm for bicentric glenoids, 27.3 mm for monocentric anterior, and 24.8 mm for monocentric central glenoids. Cartilage thickness measurement revealed the highest values in anterior parts; the thinnest cartilage was found centrally. Our findings support the principle of a physiologic incongruence in the glenohumeral joint. Bicentric mineralization patterns exist in joints consisting of more flat glenoids compared to the corresponding humeral head. Monocentric distribution with a central maximum was found in specimens with glenoids being more curved, indicating higher degrees of congruence, which might represent an early stage of degenerative disease. The obtained information might also be important for implant fixation in resurfacing procedures or to achieve the best possible fit of an osteochondral allograft in the repair of cartilage defects.

  16. Comparison of novel clinically applicable methodology for sensitive diagnostics of cartilage degeneration

    Directory of Open Access Journals (Sweden)

    P Kiviranta

    2007-04-01

    Full Text Available In order efficiently to target therapies intending to stop or reverse degenerative processes of articular cartilage, it would be crucial to diagnose osteoarthritis (OA earlier and more sensitively than is possible with the existing clinical methods. Unfortunately, current clinical methods for OA diagnostics are insensitive for detecting the early degenerative changes, e.g., arising from collagen network damage or proteoglycan depletion. We have recently investigated several novel quantitative biophysical methods, including ultrasound indentation, quantitative ultrasound techniques and magnetic resonance imaging, for diagnosing the degenerative changes of articular cartilage, typical for OA. In this study, the combined results of these novel diagnostic methods were compared with histological (Mankin score, MS, compositional (proteoglycan, collagen and water content and mechanical (dynamic and equilibrium moduli reference measurements of the same bovine cartilage samples. Receiver operating characteristics (ROC analysis was conducted to judge the diagnostic performance of each technique. Indentation and ultrasound techniques provided the most sensitive measures to differentiate samples of intact appearance (MS=0 from early (13 degeneration. Furthermore, these techniques were good predictors of tissue composition and mechanical properties. The specificity and sensitivity analyses revealed that the mechano-acoustic methods, when further developed for in vivo use, may provide more sensitive probes for OA diagnostics than the prevailing qualitative X-ray and arthroscopic techniques. Noninvasive quantitative MRI measurements showed slightly lower diagnostic performance than mechano-acoustic techniques. The compared methods could possibly also be used for the quantitative monitoring of success of cartilage repair.

  17. Micro-morphometrical assessment of the effect of Harpagophytum procumbens extract on articular cartilage in rabbits with experimental osteoarthritis using magnetic resonance imaging.

    Science.gov (United States)

    Wachsmuth, L; Lindhorst, E; Wrubel, S; Hadzhiyski, H; Hudelmaier, M; Eckstein, F; Chrubasik, S

    2011-08-01

    In vitro effects indicate a putative beneficial effect of Harpagophytum procumbens on cartilage turnover, however, in vivo protective effects on cartilage have yet to be demonstrated. A 7.1T MRI scanner was used to derive measurements of thickness, surface area and volume of the tibial condylar cartilage and to assess their precision (in the case of volume also accuracy) against the volumes of dissected cartilage measured by water displacement. Quantitative measurements were made in 16 rabbits, 6 months after unilateral medial meniscectomy and transection of the anterior cruciate ligament, after which eight of these were given a proprietary extract of Harpagophytum procumbens (HP). A semiquantitative MRI-based grading of the tibial cartilage was also compared with a 'macroscopic' grading based on direct visual inspection of dissected joints. The test-retest precision for MRI-based measurement was ≤6.4%. MRI-based measurements correlated well with volumes of surgically resected cartilage (r =  0.97, pair-wise random difference 4.2%). The medial tibial cartilage thickness and volume were about 35% smaller in the operated knees than in the non-operated contralateral knees (p < 0.05). The findings suggest that MRI is a precise and accurate tool for evaluating cartilage in a rabbit model of OA. The difference between the intact and operated knee in thickness and volume of the medial tibial cartilage was slightly but not significantly smaller in the HP-treated group than in the non-treated group. PMID:21284047

  18. Cartilage and bone cells do not participate in skeletal regeneration in Ambystoma mexicanum limbs.

    Science.gov (United States)

    McCusker, Catherine D; Diaz-Castillo, Carlos; Sosnik, Julian; Q Phan, Anne; Gardiner, David M

    2016-08-01

    The Mexican Axolotl is one of the few tetrapod species that is capable of regenerating complete skeletal elements in injured adult limbs. Whether the skeleton (bone and cartilage) plays a role in the patterning and contribution to the skeletal regenerate is currently unresolved. We tested the induction of pattern formation, the effect on cell proliferation, and contributions of skeletal tissues (cartilage, bone, and periosteum) to the regenerating axolotl limb. We found that bone tissue grafts from transgenic donors expressing GFP fail to induce pattern formation and do not contribute to the newly regenerated skeleton. Periosteum tissue grafts, on the other hand, have both of these activities. These observations reveal that skeletal tissue does not contribute to the regeneration of skeletal elements; rather, these structures are patterned by and derived from cells of non-skeletal connective tissue origin. PMID:27316294

  19. Cartilage and bone cells do not participate in skeletal regeneration in Ambystoma mexicanum limbs.

    Science.gov (United States)

    McCusker, Catherine D; Diaz-Castillo, Carlos; Sosnik, Julian; Q Phan, Anne; Gardiner, David M

    2016-08-01

    The Mexican Axolotl is one of the few tetrapod species that is capable of regenerating complete skeletal elements in injured adult limbs. Whether the skeleton (bone and cartilage) plays a role in the patterning and contribution to the skeletal regenerate is currently unresolved. We tested the induction of pattern formation, the effect on cell proliferation, and contributions of skeletal tissues (cartilage, bone, and periosteum) to the regenerating axolotl limb. We found that bone tissue grafts from transgenic donors expressing GFP fail to induce pattern formation and do not contribute to the newly regenerated skeleton. Periosteum tissue grafts, on the other hand, have both of these activities. These observations reveal that skeletal tissue does not contribute to the regeneration of skeletal elements; rather, these structures are patterned by and derived from cells of non-skeletal connective tissue origin.

  20. Microbial growth and biofilm formation in geologic media is detected with complex conductivity measurements

    Science.gov (United States)

    Davis, Caroline A.; Atekwana, Estella; Atekwana, Eliot; Slater, Lee D.; Rossbach, Silvia; Mormile, Melanie R.

    2006-09-01

    Complex conductivity measurements (0.1-1000 Hz) were obtained from biostimulated sand-packed columns to investigate the effect of microbial growth and biofilm formation on the electrical properties of porous media. Microbial growth was verified by direct microbial counts, pH measurements, and environmental scanning electron microscope imaging. Peaks in imaginary (interfacial) conductivity in the biostimulated columns were coincident with peaks in the microbial cell concentrations extracted from sands. However, the real conductivity component showed no discernible relationship to microbial cell concentration. We suggest that the observed dynamic changes in the imaginary conductivity (σ″) arise from the growth and attachment of microbial cells and biofilms to sand surfaces. We conclude that complex conductivity techniques, specifically imaginary conductivity measurements are a proxy indicator for microbial growth and biofilm formation in porous media. Our results have implications for microbial enhanced oil recovery, CO2 sequestration, bioremediation, and astrobiology studies.

  1. Constraining stellar binary black hole formation scenarios with eLISA eccentricity measurements

    CERN Document Server

    Nishizawa, Atsushi; Berti, Emanuele; Klein, Antoine

    2016-01-01

    A space-based interferometer such as eLISA could observe few to few thousands progenitors of black hole binaries (BHBs) similar to those recently detected by Advanced LIGO. Gravitational radiation circularizes the orbit during inspiral, but some BHBs retain a measurable eccentricity at the low frequencies where eLISA is most sensitive. The eccentricity of a BHB carries precious information about its formation channel: BHBs formed in the field, in globular clusters, or close to a massive black hole (MBH) have distinct eccentricity distributions in the eLISA band. We generate mock eLISA observations, folding in measurement errors, and using Bayesian model selection we study whether eLISA measurements can identify the BHB formation channel. We find that a handful of observations would suffice to tell whether BHBs were formed in the gravitational field of a MBH. Conversely, several tens of observations are needed to tell apart field formation from globular cluster formation. A five-year eLISA mission with the lon...

  2. Computational justification for engineering measures preventing the ice dams formation on the pitched roofs

    Directory of Open Access Journals (Sweden)

    Gorshkov A.S.

    2012-05-01

    Full Text Available The following article deals with the problem of icicles formation on the roofs and the elimination methods. The attic roofs with pitched roofing are highly susceptible to this negative phenomenon.This research regards the generation of heat balance equation for cold attics. Using this equation, the engineering and technical substantiation for the list of measures preventing ice mounds formation in the roofs during the period with lowest outside temperature is made.With no ice mound the roofing remains perfectly safe after snow removal, its working lifespan extends and the leakages probability decreases.

  3. Hydrogels as a Replacement Material for Damaged Articular Hyaline Cartilage

    Directory of Open Access Journals (Sweden)

    Charlotte M. Beddoes

    2016-06-01

    Full Text Available Hyaline cartilage is a strong durable material that lubricates joint movement. Due to its avascular structure, cartilage has a poor self-healing ability, thus, a challenge in joint recovery. When severely damaged, cartilage may need to be replaced. However, currently we are unable to replicate the hyaline cartilage, and as such, alternative materials with considerably different properties are used. This results in undesirable side effects, including inadequate lubrication, wear debris, wear of the opposing articular cartilage, and weakening of the surrounding tissue. With the number of surgeries for cartilage repair increasing, a need for materials that can better mimic cartilage, and support the surrounding material in its typical function, is becoming evident. Here, we present a brief overview of the structure and properties of the hyaline cartilage and the current methods for cartilage repair. We then highlight some of the alternative materials under development as potential methods of repair; this is followed by an overview of the development of tough hydrogels. In particular, double network (DN hydrogels are a promising replacement material, with continually improving physical properties. These hydrogels are coming closer to replicating the strength and toughness of the hyaline cartilage, while offering excellent lubrication. We conclude by highlighting several different methods of integrating replacement materials with the native joint to ensure stability and optimal behaviour.

  4. Linear and Nonlinear Relative Navigation Strategies for Small Satellite Formation Flying Based on Relative Position Measurement

    Science.gov (United States)

    Zhang, Xiaomin; Zheng, You

    Based on linear and nonlinear mathematical model of spacecraft formation flying and technology of relative position measurement of small satellites, the linear and nonlinear relative navigation strategies are developed in this paper. The dynamical characteristics of multi spacecraft formation flying have been researched in many references, including the authors' several International Astronautical Congress papers with numbers of IAF-98-A.2.06, IAA-99-IAA.11.1.09, IAA-01-IAA.11.4.08. Under conditions of short distance and short time, the linear model can describe relative orbit motion; otherwise, nonlinear model must be adopted. Furthermore the means of measurement and their error will influence relative navigation. Thus three kinds of relative navigation strategy are progressed. With consideration of difficulty in relative velocity measurement of small satellites, the three relative navigation strategies are proposed and only depend on sequential data of relative position through measuring the relative distance and relative orientation. The first kind of relative navigation strategy is based on linear model. The second relative navigation strategy is based on nonlinear model, with inclusion of the second order item. In fact the measurement error can not be avoided especially for small satellites, it is mainly considered in the third relative navigation strategy. This research is theoretical yet and a series of formulas of relative navigation are presented in this paper. Also the authors analyzed the three strategies qualitatively and quantitatively. According to results of simulation, the ranges of application are indicated and suggested in allusion to the three strategies of relative navigation. On the view of authors, the relative navigation strategies for small satellite formation flying based on relative position measurement are significant for engineering of small satellite formation flying.

  5. Use of micro-computed tomography to evaluate the effects of exercise on preventing the degeneration of articular cartilage in tail-suspended rats

    Science.gov (United States)

    Luan, Hui-Qin; Sun, Lian-Wen; Huang, Yun-Fei; Wu, Xin-tong; Niu, Haijun; Liu, Hong; Fan, Yu-Bo

    2015-07-01

    Space flight has been shown to induce bone loss and muscle atrophy, which could initiate the degeneration of articular cartilage. Countermeasures to prevent bone loss and muscle atrophy have been explored, but few spaceflight or ground-based studies have focused on the effects on cartilage degeneration. In this study, we investigated the effects of exercise on articular cartilage deterioration in tail-suspended rats. Thirty-two female Sprague-Dawley rats were randomly divided into four groups (n = 8 in each): tail suspension (TS), tail suspension plus passive motion (TSP), tail suspension plus active exercise (TSA), and control (CON) groups. In the TS, TSP, and TSA groups, the rat hindlimbs were unloaded for 21 days by tail suspension. Next, the cartilage thickness and volume, and the attenuation coefficient of the distal femur were evaluated by micro-computed tomography (μCT). Histological analysis was used to assess the surface integrity of the cartilage, cartilage thickness, and chondrocytes. The results showed that: (1) the cartilage thickness on the distal femur was significantly lower in the TS and TSP groups compared with the CON and TSA groups; (2) the cartilage volume in the TS group was significantly lower compared with the CON, TSA, and TSP groups; and (3) histomorphology showed that the chondrocytes formed clusters where the degree of matrix staining was lower in the TS and TSP groups. There were no significant differences between any of these parameters in the CON and TSA groups. The cartilage thickness measurements obtained by μCT and histomorphology correlated well. In general, tail suspension could induce articular cartilage degeneration, but active exercise was effective in preventing this degeneration in tail-suspended rats.

  6. An ultrasound biomicroscopic and water jet ultrasound indentation method for detecting the degenerative changes of articular cartilage in a rabbit model of progressive osteoarthritis.

    Science.gov (United States)

    Wang, Yuexiang; Huang, Yan-Ping; Liu, Aijun; Wan, Wenbo; Zheng, Yong-Ping

    2014-06-01

    It is important to assess the early degeneration of articular cartilage associated with osteoarthritis (OA) for early intervention and treatment planning. Previously, we have developed a high frequency ultrasound and water jet indentation method for the morphologic, acoustic and mechanical assessment of articular cartilage, using the enzymatic digestion as a model of osteoarthritic degeneration. No naturally degenerated articular cartilage has been tested with the developed method. In this study, we aimed to determine the usefulness of the developed method for detecting the natural degeneration of articular cartilage in a standard surgical model of OA in rabbits. Forty adult New Zealand white female rabbits were used in this study, which included 30 experimental rabbits undergoing the right anterior cruciate ligament transection surgery and 10 control rabbits. At the 3rd, 6th, and 9th week post-surgery, 10 experimental rabbits were sacrificed, respectively, for assessment of the knee cartilage quality. The cartilage at the medial and lateral femoral condyles and tibial plateaus (four points) was measured by the high frequency ultrasound biomicroscopy, the water jet ultrasound indentation and a contact mechanical indentation test before a histopathologic analysis for grading of degeneration severity. Measured parameters were compared among different groups classified either by post-surgery time or by histopathologic grade. The results showed a general trend of increase for ultrasound roughness index and a general trend of decrease for integrated reflection coefficient, stiffness coefficient from water-jet indentation and Young's modulus (E) from the mechanical indentation with the increase of post-surgery time. Comparisons among groups with different histopathologic grades showed similar trend with the increase of degeneration severity. The water jet ultrasound indentation method was demonstrated to be an effective method to measure the mechanical properties of the

  7. Identification of stable normalization genes for quantitative real-time PCR in porcine articular cartilage

    Directory of Open Access Journals (Sweden)

    McCulloch Ryan S

    2012-11-01

    Full Text Available Abstract Background Expression levels for genes of interest must be normalized with an appropriate reference, or housekeeping gene, to make accurate comparisons of quantitative real-time PCR results. The purpose of this study was to identify the most stable housekeeping genes in porcine articular cartilage subjected to a mechanical injury from a panel of 10 candidate genes. Results Ten candidate housekeeping genes were evaluated in three different treatment groups of mechanically impacted porcine articular cartilage. The genes evaluated were: beta actin, beta-2-microglobulin, glyceraldehyde-3-phosphate dehydrogenase, hydroxymethylbilane synthase, hypoxanthine phosphoribosyl transferase, peptidylprolyl isomerase A (cyclophilin A, ribosomal protein L4, succinate dehydrogenase flavoprotein subunit A, TATA box binding protein, and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein—zeta polypeptide. The stability of the genes was measured using geNorm, BestKeeper, and NormFinder software. The four most stable genes measured via geNorm were (most to least stable succinate dehydrogenase flavoprotein, subunit A, peptidylprolyl isomerase A, glyceraldehyde-3-phosphate dehydrogenase, beta actin; the four most stable genes measured via BestKeeper were glyceraldehyde-3-phosphate dehydrogenase, peptidylprolyl isomerase A, beta actin, succinate dehydrogenase flavoprotein, subunit A; and the four most stable genes measured via NormFinder were peptidylprolyl isomerase A, succinate dehydrogenase flavoprotein, subunit A, glyceraldehyde-3-phosphate dehydrogenase, beta actin. Conclusions BestKeeper, geNorm, and NormFinder all generated similar results for the most stable genes in porcine articular cartilage. The use of these appropriate reference genes will facilitate accurate gene expression studies of porcine articular cartilage and suggest appropriate housekeeping genes for articular cartilage studies in other species.

  8. Sourceless formation evaluation. An LWD solution providing density and neutron measurements without the use of radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, R.; Reichel, N. [Schlumberger, Sungai Buloh (Malaysia)

    2013-08-01

    For many years the industry has been searching for a way to eliminate the logistical difficulties and risk associated with deployment of radioisotopes for formation evaluation. The traditional gamma-gamma density (GGD) measurement uses the scattering of 662-keV gamma rays from a 137Cs radioisotopic source, with a 30.17-year half-life, to determine formation density. The traditional neutron measurement uses an Am-Be source emitting neutrons with an energy around 4 MeV, with a half-life of 432 years. Both these radioisotopic sources pose health, security, and environmental risks. Pulsed-neutron generators have been used in the industry for several decades in wireline tools and more recently in logging-while-drilling tools. These generators produce 14-MeV neutrons, many of which interact with the nuclei in the formation. Elastic collisions allow a neutron porosity measurement to be derived, which has been available to the industry since 2005. Inelastic interactions are typically followed by the emission of a variety of high-energy gamma rays. Similar to the case of the GGD measurement, the transport and attenuation of these gamma rays is a strong function of the formation density. However, the gamma-ray source is now distributed over a volume within the formation, where gamma rays have been induced by neutron interactions and the source can no longer be considered to be a point as in the case of a radioisotopic source. In addition, the extent of the induced source region depends on the transport of the fast neutrons from the source to the point of gamma-ray production. Even though the physics is more complex, it is possible to measure the formation density if the fast neutron transport is taken into account when deriving the density answer. This paper briefly reviews the physics underlying the sourceless neutron porosity and recently introduced neutron-gamma density (SNGD) measurement, demonstrates how they can be used in traditional workflows and illustrates their

  9. Analysis of friction between articular cartilage and polyvinyl alcohol hydrogel artificial cartilage.

    Science.gov (United States)

    Li, Feng; Wang, Anmin; Wang, Chengtao

    2016-05-01

    Many biomaterials are being used to repair damaged articular cartilage. In particular, poly vinyl alcohol hydrogel has similar mechanical properties to natural cartilage under compressive and shearing loading. Here, three-factor and two-level friction experiments and long-term tests were conducted to better evaluate its tribological properties. The friction coefficient between articular cartilage and the poly vinyl alcohol hydrogel depended primarily on the three factors of load, speed, and lubrication. When the speed increased from 10 to 20 mm/s under a load of 10 N, the friction coefficient increased from 0.12 to 0.147. When the lubricant was changed from Ringer's solution to a hyaluronic acid solution, the friction coefficient decreased to 0.084 with loads as high as 22 N. The poly vinyl alcohol hydrogel was severely damaged and lost its top surface layers, which were transferred to the articular cartilage surface. Wear was observed in the surface morphologies, which indicated the occurrence of surface adhesion of bovine cartilage. Surface fatigue and adhesive wear was the dominant wear mechanism. PMID:26970769

  10. Modeling the Insulin-Like Growth Factor System in Articular Cartilage.

    Directory of Open Access Journals (Sweden)

    Lihai Zhang

    Full Text Available IGF signaling is involved in cell proliferation, differentiation and apoptosis in a wide range of tissues, both normal and diseased, and so IGF-IR has been the focus of intense interest as a promising drug target. In this computational study on cartilage, we focus on two questions: (i what are the key factors influencing IGF-IR complex formation, and (ii how might cells regulate IGF-IR complex formation? We develop a reaction-diffusion computational model of the IGF system involving twenty three parameters. A series of parametric and sensitivity studies are used to identify the key factors influencing IGF signaling. From the model we predict the free IGF and IGF-IR complex concentrations throughout the tissue. We estimate the degradation half-lives of free IGF-I and IGFBPs in normal cartilage to be 20 and 100 mins respectively, and conclude that regulation of the IGF half-life, either directly or indirectly via extracellular matrix IGF-BP protease concentrations, are two critical factors governing the IGF-IR complex formation in the cartilage. Further we find that cellular regulation of IGF-II production, the IGF-IIR concentration and its clearance rate, all significantly influence IGF signaling. It is likely that negative feedback processes via regulation of these factors tune IGF signaling within a tissue, which may help explain the recent failures of single target drug therapies aimed at modifying IGF signaling.

  11. Modeling the Insulin-Like Growth Factor System in Articular Cartilage

    Science.gov (United States)

    Zhang, Lihai; Smith, David W.; Gardiner, Bruce S.; Grodzinsky, Alan J.

    2013-01-01

    IGF signaling is involved in cell proliferation, differentiation and apoptosis in a wide range of tissues, both normal and diseased, and so IGF-IR has been the focus of intense interest as a promising drug target. In this computational study on cartilage, we focus on two questions: (i) what are the key factors influencing IGF-IR complex formation, and (ii) how might cells regulate IGF-IR complex formation? We develop a reaction-diffusion computational model of the IGF system involving twenty three parameters. A series of parametric and sensitivity studies are used to identify the key factors influencing IGF signaling. From the model we predict the free IGF and IGF-IR complex concentrations throughout the tissue. We estimate the degradation half-lives of free IGF-I and IGFBPs in normal cartilage to be 20 and 100 mins respectively, and conclude that regulation of the IGF half-life, either directly or indirectly via extracellular matrix IGF-BP protease concentrations, are two critical factors governing the IGF-IR complex formation in the cartilage. Further we find that cellular regulation of IGF-II production, the IGF-IIR concentration and its clearance rate, all significantly influence IGF signaling. It is likely that negative feedback processes via regulation of these factors tune IGF signaling within a tissue, which may help explain the recent failures of single target drug therapies aimed at modifying IGF signaling. PMID:23840540

  12. Cartilage restoration technique of the hip.

    Science.gov (United States)

    Mardones, Rodrigo; Larrain, Catalina

    2016-04-01

    Hip cartilage lesions represent a diagnostic challenge and can be an elusive source of pain. Treatment may present difficulties due to localization and spherical form of the joint and is most commonly limited to excision, debridement, thermal chondroplasty and microfractures. This chapter will focus in new technologies to enhance the standard techniques. These new technologies are based in stem cells therapies; as intra-articular injections of expanded mesenchymal stem cells, mononuclear concentrate in a platelet-rich plasma matrix and expanded mesenchymal stem cells seeded in a collagen membrane. This review will discuss the bases, techniques and preliminary results obtained with the use of stem cells for the treatment of hip cartilage lesions. PMID:27026816

  13. Bioprinted Scaffolds for Cartilage Tissue Engineering.

    Science.gov (United States)

    Kang, Hyun-Wook; Yoo, James J; Atala, Anthony

    2015-01-01

    Researchers are focusing on bioprinting technology as a viable option to overcome current difficulties in cartilage tissue engineering. Bioprinting enables a three-dimensional (3-D), free-form, computer-designed structure using biomaterials, biomolecules, and/or cells. The inner and outer shape of a scaffold can be controlled by this technology with great precision. Here, we introduce a hybrid bioprinting technology that is a co-printing process of multiple materials including high-strength synthetic polymer and cell-laden hydrogel. The synthetic polymer provides mechanical support for shape maintenance and load bearing, while the hydrogel provides the biological environment for artificial cartilage regeneration. This chapter introduces the procedures for printing of a 3-D scaffold using our hybrid bioprinting technology and includes the source materials for preparation of 3-D printing. PMID:26445837

  14. Comparing the content of type II collagen from different parts of costal cartilage and auricular cartilage%不同部位肋软骨与耳软骨的Ⅱ型胶原蛋白差异性比较

    Institute of Scientific and Technical Information of China (English)

    张中航; 陈振宇

    2016-01-01

    Objective To compare the content of typeⅡcollagen between the autologous 6th,7th,8th costal cartilages and auricular cartilages. Methods By using florescent real-time quantitative PCR methods to test the level of mRNA of typeIIcollagen in the autologous 6th,7th,8th costal cartilages and auricular cartilages. By using immunohistochemistry and HE staining methods to test the protein content of typeIIcollagen and the amount of chondrocytes in the 6th,7th ,8th costal cartilage and auricular cartilage.Results The type II collagen mRNA’s level in 6th,7th,8th costal cartilages were significantly higher than that in the auricular cartilage(9.3±1.2,8.9±0.5,9.7±1.3 vs. 0.8±0.6);The typeⅡcollagen’s the relative gray value in 6th,7th,8th costal cartilages were significantly higher than that in the auricular cartilage(14 545±398,15807±736,13 257±802 vs. 6 310±514;The measurement of chondrocytes in 6th,7th,8th costal cartilages were significantly more than that in the auricular cartilage. Conclusion The amount of chondrocytes and the expression of typeⅡcollagenin autologous 6th,7th,8th costal cartilages were more than auricular cartilage in patients. The autologous 6th,7th,8th costal cartilages were the best choice for auricular scaffold on ear reconstruction.%目的:比较第6、7、8肋软骨以及耳软骨的Ⅱ型胶原蛋白含量。方法利用RT-PCR检测方式测得Ⅱ型胶原蛋白mRNA在第6、7、8肋软骨和耳软骨中的表达。利用免疫组化以及HE染色方法检测第6、7、8肋软骨和耳软骨中Ⅱ型胶原蛋白和软骨细胞的含量。结果Ⅱ型胶原蛋白mRNA在第6、7、8肋软骨的表达明显高于耳软骨(9.3±1.2、8.9±0.5、9.7±1.3 vs.0.8±0.6);第6、7、8肋软骨的Ⅱ型胶原蛋白相对灰度值明显高于耳软骨(14545±398、15807±736、13257±802 vs.6310±514);第6、7、8肋软骨测量的软骨细胞数目明显多于患者耳软骨。结论自体第6、7、8肋软骨Ⅱ型胶原蛋白

  15. Time-Dependent Nanomechanics of Cartilage

    OpenAIRE

    Han, Lin; Frank, Eliot H.; Greene, Jacqueline J.; Lee, Hsu-Yi; Hung, Han-Hwa K.; Grodzinsky, Alan J.; Ortiz, Christine

    2011-01-01

    In this study, atomic force microscopy-based dynamic oscillatory and force-relaxation indentation was employed to quantify the time-dependent nanomechanics of native (untreated) and proteoglycan (PG)-depleted cartilage disks, including indentation modulus Eind, force-relaxation time constant τ, magnitude of dynamic complex modulus |E∗|, phase angle δ between force and indentation depth, storage modulus E′, and loss modulus E″. At ∼2 nm dynamic deformation amplitude, |E∗| increased significant...

  16. Cartilage restoration technique of the hip

    OpenAIRE

    Mardones, Rodrigo; Larrain, Catalina

    2015-01-01

    Hip cartilage lesions represent a diagnostic challenge and can be an elusive source of pain. Treatment may present difficulties due to localization and spherical form of the joint and is most commonly limited to excision, debridement, thermal chondroplasty and microfractures. This chapter will focus in new technologies to enhance the standard techniques. These new technologies are based in stem cells therapies; as intra-articular injections of expanded mesenchymal stem cells, mononuclear conc...

  17. Articular cartilage collagen: an irreplaceable framework?

    OpenAIRE

    Eyre, D. R.; Weis, M A; J-J Wu

    2006-01-01

    Adult articular cartilage by dry weight is two-thirds collagen. The collagen has a unique molecular phenotype. The nascent type II collagen fibril is a heteropolymer, with collagen IX molecules covalently linked to the surface and collagen XI forming the filamentous template of the fibril as a whole. The functions of collagens IX and XI in the heteropolymer are far from clear but, evidently, they are critically important since mutations in COLIX and COLXI genes can result in chondrodysplasia ...

  18. Oxygen, nitric oxide and articular cartilage

    OpenAIRE

    Fermor, B.; Christensen, S. E.; I Youn; J M Cernanec; C M Davies; Weinberg, J. B.

    2007-01-01

    Molecular oxygen is required for the production of nitric oxide (NO), a pro-inflammatory mediator that is associated with osteoarthritis and rheumatoid arthritis. To date there has been little consideration of the role of oxygen tension in the regulation of nitric oxide production associated with arthritis. Oxygen tension may be particularly relevant to articular cartilage since it is avascular and therefore exists at a reduced oxygen tension. The superficial zone exists at approximately 6% O...

  19. Growth factor stimulation improves the structure and properties of scaffold-free engineered auricular cartilage constructs.

    Directory of Open Access Journals (Sweden)

    Renata G Rosa

    Full Text Available The reconstruction of the external ear to correct congenital deformities or repair following trauma remains a significant challenge in reconstructive surgery. Previously, we have developed a novel approach to create scaffold-free, tissue engineering elastic cartilage constructs directly from a small population of donor cells. Although the developed constructs appeared to adopt the structural appearance of native auricular cartilage, the constructs displayed limited expression and poor localization of elastin. In the present study, the effect of growth factor supplementation (insulin, IGF-1, or TGF-β1 was investigated to stimulate elastogenesis as well as to improve overall tissue formation. Using rabbit auricular chondrocytes, bioreactor-cultivated constructs supplemented with either insulin or IGF-1 displayed increased deposition of cartilaginous ECM, improved mechanical properties, and thicknesses comparable to native auricular cartilage after 4 weeks of growth. Similarly, growth factor supplementation resulted in increased expression and improved localization of elastin, primarily restricted within the cartilaginous region of the tissue construct. Additional studies were conducted to determine whether scaffold-free engineered auricular cartilage constructs could be developed in the 3D shape of the external ear. Isolated auricular chondrocytes were grown in rapid-prototyped tissue culture molds with additional insulin or IGF-1 supplementation during bioreactor cultivation. Using this approach, the developed tissue constructs were flexible and had a 3D shape in very good agreement to the culture mold (average error <400 µm. While scaffold-free, engineered auricular cartilage constructs can be created with both the appropriate tissue structure and 3D shape of the external ear, future studies will be aimed assessing potential changes in construct shape and properties after subcutaneous implantation.

  20. Gamma ray measurement of earth formation properties using a position sensitive scintillation detector

    International Nuclear Information System (INIS)

    This patent describes a system for measuring properties of earth formations in the vicinity of a well borehole at different radial distances from the borehole, comprising: a fluid tight hollow body member sized and adapted for passage through a well borehole and housing therein; a source of gamma rays and means for directing gamma rays from the source outwardly from the body member into earth formations in the vicinity of the borehole; and a position sensitive scintillation detector for detecting gamma rays scattered back into the body member from the earth formation in the vicinity of the borehole, means for collimating the scattered gamma rays onto the detector. The detector comprises scintillation crystal means having discrete longitudinally spaced active regions or bins and is longitudinally spaced from the gamma ray source. It has a longitudinal length L and two opposite ends and photomultiplier tubes optically coupled to the opposite ends for providing output voltage signals having voltage amplitudes A and B representative of the intensity of scintillation events occurring in the crystal and impinging at the opposite ends thereof. A means separates the bins for selectively attenuating light passing therebetween, and a means combines the output voltage signals A and B according to a predetermined relationship to derive the discrete bin along the length L of each of the scintillation events in the crystal, thereby providing measurements of the gamma ray scattering properties of the earth formations at different radial distances from the borehole

  1. High Throughput Measurement of Extracellular DNA Release and Quantitative NET Formation in Human Neutrophils In Vitro.

    Science.gov (United States)

    Sil, Payel; Yoo, Dae-Goon; Floyd, Madison; Gingerich, Aaron; Rada, Balazs

    2016-06-18

    Neutrophil granulocytes are the most abundant leukocytes in the human blood. Neutrophils are the first to arrive at the site of infection. Neutrophils developed several antimicrobial mechanisms including phagocytosis, degranulation and formation of neutrophil extracellular traps (NETs). NETs consist of a DNA scaffold decorated with histones and several granule markers including myeloperoxidase (MPO) and human neutrophil elastase (HNE). NET release is an active process involving characteristic morphological changes of neutrophils leading to expulsion of their DNA into the extracellular space. NETs are essential to fight microbes, but uncontrolled release of NETs has been associated with several disorders. To learn more about the clinical relevance and the mechanism of NET formation, there is a need to have reliable tools capable of NET quantitation. Here three methods are presented that can assess NET release from human neutrophils in vitro. The first one is a high throughput assay to measure extracellular DNA release from human neutrophils using a membrane impermeable DNA-binding dye. In addition, two other methods are described capable of quantitating NET formation by measuring levels of NET-specific MPO-DNA and HNE-DNA complexes. These microplate-based methods in combination provide great tools to efficiently study the mechanism and regulation of NET formation of human neutrophils.

  2. The Star Formation Efficiency in Nearby Galaxies: Measuring Where Gas Forms Stars Effectively

    CERN Document Server

    Leroy, Adam K; Brinks, Elias; Bigiel, Frank; De Blok, W J G; Madore, Barry; Thornley, M D

    2008-01-01

    We measure the star formation efficiency (SFE), the star formation rate per unit gas, in 23 nearby galaxies and compare it to expectations from proposed star formation laws and thresholds. We use HI maps from THINGS and derive H2 maps from HERACLES and BIMA SONG CO. We estimate the star formation rate by combining GALEX FUV maps and SINGS 24 micron maps, infer stellar surface density profiles from SINGS 3.6 micron data, and use kinematics from THINGS. We measure the SFE as a function of: the free-fall and orbital timescales; midplane gas pressure; stability of the gas disk to collapse (including the effects of stars); the ability of perturbations to grow despite shear; and the ability of a cold phase to form. In spirals, the SFE of H2 alone is nearly constant at 5.25 +/- 2.5 x 10^(-10) yr^(-1) (equivalent to an H2 depletion time of 1.9x10^9 yr) as a function of all of these variables at our 800 pc resolution. Where the ISM is mostly HI, on the other hand, the SFE decreases with increasing radius in both spira...

  3. Planck 2013 results. XXX. Cosmic infrared background measurements and implications for star formation

    Science.gov (United States)

    Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.; Arnaud, M.; Ashdown, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartlett, J. G.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bethermin, M.; Bielewicz, P.; Blagrave, K.; Bobin, J.; Bock, J. J.; Bonaldi, A.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Bridges, M.; Bucher, M.; Burigana, C.; Butler, R. C.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chen, X.; Chiang, H. C.; Chiang, L.-Y.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Delouis, J.-M.; Désert, F.-X.; Dickinson, C.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Dupac, X.; Efstathiou, G.; Enßlin, T. A.; Eriksen, H. K.; Finelli, F.; Forni, O.; Frailis, M.; Franceschi, E.; Galeotta, S.; Ganga, K.; Ghosh, T.; Giard, M.; Giraud-Héraud, Y.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Hansen, F. K.; Hanson, D.; Harrison, D.; Helou, G.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huffenberger, K. M.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Juvela, M.; Kalberla, P.; Keihänen, E.; Kerp, J.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Knox, L.; Kunz, M.; Kurki-Suonio, H.; Lacasa, F.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Langer, M.; Lasenby, A.; Laureijs, R. J.; Lawrence, C. R.; Leonardi, R.; León-Tavares, J.; Lesgourgues, J.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maffei, B.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martin, P. G.; Martínez-González, E.; Masi, S.; Massardi, M.; Matarrese, S.; Matthai, F.; Mazzotta, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Osborne, S.; Oxborrow, C. A.; Paci, F.; Pagano, L.; Pajot, F.; Paladini, R.; Paoletti, D.; Partridge, B.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Poutanen, T.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Roudier, G.; Rowan-Robinson, M.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savini, G.; Scott, D.; Seiffert, M. D.; Serra, P.; Shellard, E. P. S.; Spencer, L. D.; Starck, J.-L.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sureau, F.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Tavagnacco, D.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Türler, M.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Vittorio, N.; Wade, L. A.; Wandelt, B. D.; Welikala, N.; White, M.; White, S. D. M.; Winkel, B.; Yvon, D.; Zacchei, A.; Zonca, A.

    2014-11-01

    We present new measurements of cosmic infrared background (CIB) anisotropies using Planck. Combining HFI data with IRAS, the angular auto- and cross-frequency power spectrum is measured from 143 to 3000 GHz, and the auto-bispectrum from 217 to 545 GHz. The total areas used to compute the CIB power spectrum and bispectrum are about 2240 and 4400 deg2, respectively. After careful removal of the contaminants (cosmic microwave background anisotropies, Galactic dust, and Sunyaev-Zeldovich emission), and a complete study of systematics, the CIB power spectrum is measured with unprecedented signal to noise ratio from angular multipoles ℓ ~ 150 to 2500. The bispectrum due to the clustering of dusty, star-forming galaxies is measured from ℓ ~ 130 to 1100, with a total signal to noise ratio of around 6, 19, and 29 at 217, 353, and 545 GHz, respectively. Two approaches are developed for modelling CIB power spectrum anisotropies. The first approach takes advantage of the unique measurements by Planck at large angular scales, and models only the linear part of the power spectrum, with a mean bias of dark matter haloes hosting dusty galaxies at a given redshift weighted by their contribution to the emissivities. The second approach is based on a model that associates star-forming galaxies with dark matter haloes and their subhaloes, using a parametrized relation between the dust-processed infrared luminosity and (sub-)halo mass. The two approaches simultaneously fit all auto- and cross-power spectra very well. We find that the star formation history is well constrained up to redshifts around 2, and agrees with recent estimates of the obscured star-formation density using Spitzer and Herschel. However, at higher redshift, the accuracy of the star formation history measurement is strongly degraded by the uncertainty in the spectral energy distribution of CIB galaxies. We also find that the mean halo mass which is most efficient at hosting star formation is log (Meff/M⊙) = 12

  4. Formative evaluation: Developing measures for online family mental health recovery education.

    Science.gov (United States)

    Rue, Lisa A; Estrada, Samantha; Floren, Michael; MacKinnon, Krista

    2016-04-01

    Families facing mental health challenges have very limited access to ongoing support. A formative evaluation of Families Healing Together (FHT), a new online family mental health recovery program was conducted using five waves (N=108) of data. Exploratory factor analysis of the measures identified as important to the program theory found strong reliability evidence (α=.77-.86) for 6 constructs. A poor response rate (25%) did not allow for valid pre and postoutcome evaluation, however we did have enough information to assess the psychometric properties of the new measures. The new evaluation tool accounted for 34% of the variance in Capacity to Support Family Member, and nearly 50% of the variance in Hopefulness toward Recovery. New programs without existing measures require formative evaluation strategies that accurately describe program activities in order to develop outcome measures sensitive to novel aspects of program components. Most outcome measures are developed for individuals with mental health challenges not family members. These new measures may be beneficial to effectively evaluate programs that promote family recovery and wellness.

  5. Optimization and translation of MSC-based hyaluronic acid hydrogels for cartilage repair

    Science.gov (United States)

    Erickson, Isaac E.

    2011-12-01

    Traumatic injury and disease disrupt the ability of cartilage to carry joint stresses and, without an innate regenerative response, often lead to degenerative changes towards the premature development of osteoarthritis. Surgical interventions have yet to restore long-term mechanical function. Towards this end, tissue engineering has been explored for the de novo formation of engineered cartilage as a biologic approach to cartilage repair. Research utilizing autologous chondrocytes has been promising, but clinical limitations in their yield have motivated research into the potential of mesenchymal stem cells (MSCs) as an alternative cell source. MSCs are multipotent cells that can differentiate towards a chondrocyte phenotype in a number of biomaterials, but no combination has successfully recapitulated the native mechanical function of healthy articular cartilage. The broad objective of this thesis was to establish an MSC-based tissue engineering approach worthy of clinical translation. Hydrogels are a common class of biomaterial used for cartilage tissue engineering and our initial work demonstrated the potential of a photo-polymerizable hyaluronic acid (HA) hydrogel to promote MSC chondrogenesis and improved construct maturation by optimizing macromer and MSC seeding density. The beneficial effects of dynamic compressive loading, high MSC density, and continuous mixing (orbital shaker) resulted in equilibrium modulus values over 1 MPa, well in range of native tissue. While compressive properties are crucial, clinical translation also demands that constructs stably integrate within a defect. We utilized a push-out testing modality to assess the in vitro integration of HA constructs within artificial cartilage defects. We established the necessity for in vitro pre-maturation of constructs before repair to achieve greater integration strength and compressive properties in situ. Combining high MSC density and gentle mixing resulted in integration strength over 500 k

  6. Time-dependent nanomechanics of cartilage.

    Science.gov (United States)

    Han, Lin; Frank, Eliot H; Greene, Jacqueline J; Lee, Hsu-Yi; Hung, Han-Hwa K; Grodzinsky, Alan J; Ortiz, Christine

    2011-04-01

    In this study, atomic force microscopy-based dynamic oscillatory and force-relaxation indentation was employed to quantify the time-dependent nanomechanics of native (untreated) and proteoglycan (PG)-depleted cartilage disks, including indentation modulus E(ind), force-relaxation time constant τ, magnitude of dynamic complex modulus |E(∗)|, phase angle δ between force and indentation depth, storage modulus E', and loss modulus E″. At ∼2 nm dynamic deformation amplitude, |E(∗)| increased significantly with frequency from 0.22 ± 0.02 MPa (1 Hz) to 0.77 ± 0.10 MPa (316 Hz), accompanied by an increase in δ (energy dissipation). At this length scale, the energy dissipation mechanisms were deconvoluted: the dynamic frequency dependence was primarily governed by the fluid-flow-induced poroelasticity, whereas the long-time force relaxation reflected flow-independent viscoelasticity. After PG depletion, the change in the frequency response of |E(∗)| and δ was consistent with an increase in cartilage local hydraulic permeability. Although untreated disks showed only slight dynamic amplitude-dependent behavior, PG-depleted disks showed great amplitude-enhanced energy dissipation, possibly due to additional viscoelastic mechanisms. Hence, in addition to functioning as a primary determinant of cartilage compressive stiffness and hydraulic permeability, the presence of aggrecan minimized the amplitude dependence of |E(∗)| at nanometer-scale deformation. PMID:21463599

  7. Technique and results of cartilage shield tympanoplasty

    Directory of Open Access Journals (Sweden)

    Sohil I Vadiya

    2014-01-01

    Full Text Available Aim: Use of cartilage for repair of tympanic membrane is recommended by many otologists. The current study aims at evaluating results of cartilage shield tympanoplasty in terms of graft take up and hearing outcomes. Material and Methods: In the current study, cartilage shield tympanoplasty(CST is used in ears with high risk perforations of the tympanic membrane. A total of 40 ears were selected where type I CST was done in 30 ears and type III CST was done in 10 ears. Results: An average of 37.08 dB air bone gap(ABG was present in pre operative time and an average of 19.15 dB of ABG was observed at 6 months after the surgery with hearing gain of 17.28 dB on average was observed. Graft take up rate of 97.5% was observed. The technique is modified to make it easier and to minimize chances of lateralization of graft. Conclusion: The hearing results of this technique are comparable to other methods of tympanic membrane repair.

  8. Irradiated homologous costal cartilage for augmentation rhinoplasty

    Energy Technology Data Exchange (ETDEWEB)

    Lefkovits, G. (Lenox Hill Hospital, New York, NY (USA))

    1990-10-01

    Although the ideal reconstructive material for augmentation rhinoplasty continues to challenge plastic surgeons, there exists no report in the literature that confines the use of irradiated homologous costal cartilage, first reported by Dingman and Grabb in 1961, to dorsal nasal augmentation. The purpose of this paper is to present a retrospective analysis of the author's experience using irradiated homologous costal cartilage in augmentation rhinoplasty. Twenty-seven dorsal nasal augmentations were performed in 24 patients between 16 and 49 years of age with a follow-up ranging from 1 to 27 months. Good-to-excellent results were achieved in 83.3% (20 of 24). Poor results requiring revision were found in 16.7% (4 of 24). Complication rates included 7.4% infection (2 of 27) and 14.8% warping (4 of 27). The resorption rate was zero. These results compare favorably with other forms of nasal augmentation. Advantages and disadvantages of irradiated homologous costal cartilage are discussed.

  9. Measurement of $\\eta '(958)$ formation in two-photon collisions at LEP1

    CERN Document Server

    Acciarri, M; Aguilar-Benítez, M; Ahlen, S P; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alverson, G; Alviggi, M G; Ambrosi, G; Anderhub, H; Andreev, V P; Angelescu, T; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Baksay, L; Ball, R C; Banerjee, S; Banerjee, Sw; Banicz, K; Barczyk, A; Barillère, R; Barone, L; Bartalini, P; Baschirotto, A; Basile, M; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Bhattacharya, S; Biasini, M; Biland, A; Bilei, G M; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böck, R K; Böhm, A; Boldizsar, L; Borgia, B; Bourilkov, D; Bourquin, Maurice; Boutigny, D; Braccini, S; Branson, J G; Brigljevic, V; Brock, I C; Buffini, A; Buijs, A; Burger, J D; Burger, W J; Busenitz, J K; Cai, X D; Campanelli, M; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Castellini, G; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada-Canales, M; Cesaroni, F; Chamizo-Llatas, M; Chang, Y H; Chaturvedi, U K; Chekanov, S V; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chen, M; Chiefari, G; Chien, C Y; Cifarelli, Luisa; Cindolo, F; Civinini, C; Clare, I; Clare, R; Cohn, H O; Coignet, G; Colijn, A P; Colino, N; Commichau, V; Costantini, S; Cotorobai, F; de la Cruz, B; Csilling, Akos; Dai, T S; D'Alessandro, R; De Asmundis, R; Degré, A; Deiters, K; Denes, P; De Notaristefani, F; DiBitonto, Daryl; Diemoz, M; Van Dierendonck, D N; Di Lodovico, F; Dionisi, C; Dittmar, Michael; Dominguez, A; Doria, A; Dova, M T; Drago, E; Duchesneau, D; Duinker, P; Durán, I; Dutta, S; Easo, S; Efremenko, Yu V; El-Mamouni, H; Engler, A; Eppling, F J; Erné, F C; Ernenwein, J P; Extermann, Pierre; Fabre, M; Faccini, R; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, Marta; Fenyi, B; Ferguson, T; Ferroni, F; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisk, I; Forconi, G; Fredj, L; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gau, S S; Gentile, S; Gerald, J; Gheordanescu, N; Giagu, S; Goldfarb, S; Goldstein, J; Gong, Z F; Gougas, Andreas; Gratta, Giorgio; Grünewald, M W; Gupta, V K; Gurtu, A; Gutay, L J; Hartmann, B; Hasan, A; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Van Hoek, W C; Hofer, H; Hong, S J; Hoorani, H; Hou, S R; Hu, G; Innocente, Vincenzo; Jenkes, K; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Kasser, A; Khan, R A; Kamrad, D; Kamyshkov, Yu A; Kapustinsky, J S; Karyotakis, Yu; Kaur, M; Kienzle-Focacci, M N; Kim, D; Kim, D H; Kim, J K; Kim, S C; Kim, Y G; Kinnison, W W; Kirkby, A; Kirkby, D; Kirkby, Jasper; Kiss, D; Kittel, E W; Klimentov, A; König, A C; Kopp, A; Korolko, I; Koutsenko, V F; Krämer, R W; Krenz, W; Kunin, A; Lacentre, P E; Ladrón de Guevara, P; Landi, G; Lapoint, C; Lassila-Perini, K M; Laurikainen, P; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Lee, H J; Leggett, C; Le Goff, J M; Leiste, R; Leonardi, E; Levchenko, P M; Li Chuan; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lu, W; Lü, Y S; Lübelsmeyer, K; Luci, C; Luckey, D; Luminari, L; Lustermann, W; Ma Wen Gan; Maity, M; Majumder, G; Malgeri, L; Malinin, A; Maña, C; Mangeol, D J J; Mangla, S; Marchesini, P A; Marin, A; Martin, J P; Marzano, F; Massaro, G G G; McNally, D; Mele, S; Merola, L; Meschini, M; Metzger, W J; Von der Mey, M; Mi, Y; Mihul, A; Van Mil, A J W; Milcent, H; Mirabelli, G; Mnich, J; Molnár, P; Monteleoni, B; Moore, R; Morganti, S; Moulik, T; Mount, R; Müller, S; Muheim, F; Muijs, A J M; Nahn, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Niessen, T; Nippe, A; Nisati, A; Nowak, H; Oh, Yu D; Opitz, H; Organtini, G; Ostonen, R; Palomares, C; Pandoulas, D; Paoletti, S; Paolucci, P; Park, H K; Park, I H; Pascale, G; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Peach, D; Pei, Y J; Pensotti, S; Perret-Gallix, D; Petersen, B; Petrak, S; Pevsner, A; Piccolo, D; Pieri, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Postema, H; Produit, N; Prokofev, D; Prokofiev, D O; Rahal-Callot, G; Raja, N; Rancoita, P G; Rattaggi, M; Raven, G; Razis, P A; Read, K; Ren, D; Rescigno, M; Reucroft, S; Van Rhee, T; Riemann, S; Riles, K; Rind, O; Rizzo, R; Robohm, A; Rodin, J; Roe, B P; Romero, L; Rosier-Lees, S; Rosselet, P; Van Rossum, W; Roth, S; Rubio, Juan Antonio; Ruschmeier, D; Rykaczewski, H; Salicio, J; Sánchez, E; Sanders, M P; Sarakinos, M E; Sarkar, S; Sassowsky, M; Sauvage, G; Schäfer, C; Shchegelskii, V; Schmidt-Kärst, S; Schmitz, D; Schmitz, P; Schneegans, M; Scholz, N; Schopper, Herwig Franz; Schotanus, D J; Schwenke, J; Schwering, G; Sciacca, C; Sciarrino, D; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shukla, J; Shumilov, E; Shvorob, A V; Siedenburg, T; Son, D; Soulimov, V; Smith, B; Spillantini, P; Steuer, M; Stickland, D P; Stone, H; Stoyanov, B; Strässner, A; Strauch, K; Sudhakar, K; Sultanov, G G; Sun, L Z; Susinno, G F; Suter, H; Swain, J D; Tang, X W; Tauscher, Ludwig; Taylor, L; Ting, Samuel C C; Ting, S M; Tonutti, M; Tonwar, S C; Tóth, J; Tully, C; Tuchscherer, H; Tung, K L; Uchida, Y; Ulbricht, J; Uwer, U; Valente, E; Van de Walle, R T; Vesztergombi, G; Vetlitskii, I; Viertel, Gert M; Vivargent, M; Völkert, R; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Vorvolakos, A; Wadhwa, M; Wallraff, W; Wang, J C; Wang, X L; Wang, Z M; Weber, A; Wittgenstein, F; Wu, S X; Wynhoff, S; Xu, J; Xu, Z Z; Yang, B Z; Yang, C G; Yao, X Y; Ye, J B; Yeh, S C; You, J M; Zalite, A; Zalite, Yu; Zemp, P; Zeng, Y; Zhang, Z; Zhang, Z P; Zhou, B; Zhou, Y; Zhu, G Y; Zhu, R Y; Zichichi, Antonino; Ziegler, F

    1998-01-01

    The formation of the eta' in the reaction ee->ee eta'->ee pi pi gamma has been measured by the L3 detector at a centre-of-mass energy of 91 GeV. The radiative width of the eta' has been found to be 4.17 +/- 0.10(stat.) +/- 0.27(sys.) keV . The Q^2 dependence of the eta' formation cross section has been measured for Q^2 < 10 GeV^2 and the eta' electromagnetic transition form factor has been determined. The form factor can be parametrised by a pole form with Lambda = 0.900 +/- 0.046(stat) +/- 0.022(sys) GeV. It is also consistent with recent non-perturbative QCD calculations.

  10. Resonant formation measurements of dtμ via time of flight

    International Nuclear Information System (INIS)

    Solid hydrogen in the form of an inhomogeneous layered target offers several experimental advantages when compared with liquid or gas. Beams of non-thermalized muonic hydrogen atoms allow us to explore resonant molecular ion formation processes near eV kinetic energies. Isotopically specific layers make it possible to separate competing and confusing interactions and to employ the time of flight for comparison with predictions based on theoretical energy dependences. Unambiguous charged fusion product detection simplifies absolute intensity measurements.The systematic uncertainties encountered in resonant molecular ion formation measurements, using solid hydrogen target layers, are being investigated with simulations which use the many calculated energy-dependent rates and cross-sections which are now available. The importance of the rates for processes such as muon transfer and elastic scattering are discussed, and results of some recent analyses are presented

  11. Ectopic mineralization of cartilage and collagen-rich tendons and ligaments in Enpp1asj-2J mice.

    Science.gov (United States)

    Zhang, Jieyu; Dyment, Nathaniel A; Rowe, David W; Siu, Sarah Y; Sundberg, John P; Uitto, Jouni; Li, Qiaoli

    2016-03-15

    Generalized arterial calcification of infancy (GACI), an autosomal recessive disorder caused by mutations in the ENPP1 gene, manifests with extensive mineralization of the cardiovascular system. A spontaneous asj-2J mutant mouse has been characterized as a model for GACI. Previous studies focused on phenotypic characterization of skin and vascular tissues. This study further examined the ectopic mineralization phenotype of cartilage, collagen-rich tendons and ligaments in this mouse model. The mice were placed on either control diet or the "acceleration diet" for up to 12 weeks of age. Soft connective tissues, such as ear (elastic cartilage) and trachea (hyaline cartilage), were processed for standard histology. Assessment of ectopic mineralization in articular cartilage and fibrocartilage as well as tendons and ligaments which are attached to long bones were performed using a novel cryo-histological method without decalcification. These analyses demonstrated ectopic mineralization in cartilages as well as tendons and ligaments in the homozygous asj-2J mice at 12 weeks of age, with the presence of immature osteophytes displaying alkaline phosphatase and tartrate-resistant acid phosphatase activities as early as at 6 weeks of age. Alkaline phosphatase activity was significantly increased in asj-2J mouse serum as compared to wild type mice, indicating increased bone formation rate in these mice. Together, these data highlight the key role of ENPP1 in regulating calcification of both soft and skeletal tissues. PMID:26910915

  12. Ectopic mineralization of cartilage and collagen-rich tendons and ligaments in Enpp1asj-2J mice

    Science.gov (United States)

    Zhang, Jieyu; Dyment, Nathaniel A.; Rowe, David W.; Siu, Sarah Y.; Sundberg, John P.; Uitto, Jouni; Li, Qiaoli

    2016-01-01

    Generalized arterial calcification of infancy (GACI), an autosomal recessive disorder caused by mutations in the ENPP1 gene, manifests with extensive mineralization of the cardiovascular system. A spontaneous asj-2J mutant mouse has been characterized as a model for GACI. Previous studies focused on phenotypic characterization of skin and vascular tissues. This study further examined the ectopic mineralization phenotype of cartilage, collagen-rich tendons and ligaments in this mouse model. The mice were placed on either control diet or the ‘acceleration diet’ for up to 12 weeks of age. Soft connective tissues, such as ear (elastic cartilage) and trachea (hyaline cartilage), were processed for standard histology. Assessment of ectopic mineralization in articular cartilage and fibrocartilage as well as tendons and ligaments which are attached to long bones were performed using a novel cryo-histological method without decalcification. These analyses demonstrated ectopic mineralization in cartilages as well as tendons and ligaments in the homozygous asj-2J mice at 12 weeks of age, with the presence of immature osteophytes displaying alkaline phosphatase and tartrate-resistant acid phosphatase activities as early as at 6 weeks of age. Alkaline phosphatase activity was significantly increased in asj-2J mouse serum as compared to wild type mice, indicating increased bone formation rate in these mice. Together, these data highlight the key role of ENPP1 in regulating calcification of both soft and skeletal tissues. PMID:26910915

  13. Stem Cell-assisted Approaches for Cartilage Tissue Engineering

    OpenAIRE

    Park, In-Kyu; Cho, Chong-Su

    2010-01-01

    The regeneration of damaged articular cartilage remains challenging due to its poor intrinsic capacity for repair. Tissue engineering of articular cartilage is believed to overcome the current limitations of surgical treatment by offering functional regeneration in the defect region. Selection of proper cell sources and ECM-based scaffolds, and incorporation of growth factors or mechanical stimuli are of primary importance to successfully produce artificial cartilage for tissue repair. When d...

  14. Regeneration of human bones in hip osteonecrosis and human cartilage in knee osteoarthritis with autologous adipose-tissue-derived stem cells: a case series

    Directory of Open Access Journals (Sweden)

    Pak Jaewoo

    2011-07-01

    Full Text Available Abstract Introduction This is a series of clinical case reports demonstrating that a combination of percutaneously injected autologous adipose-tissue-derived stem cells, hyaluronic acid, platelet rich plasma and calcium chloride may be able to regenerate bones in human osteonecrosis, and with addition of a very low dose of dexamethasone, cartilage in human knee osteoarthritis. Case reports Stem cells were obtained from adipose tissue of abdominal origin by digesting lipoaspirate tissue with collagenase. These stem cells, along with hyaluronic acid, platelet rich plasma and calcium chloride, were injected into the right hip of a 29-year-old Korean woman and a 47-year-old Korean man. They both had a history of right hip osteonecrosis of the femoral head. For cartilage regeneration, a 70-year-old Korean woman and a 79-year-old Korean woman, both with a long history of knee pain due to osteoarthritis, were injected with stem cells along with hyaluronic acid, platelet rich plasma, calcium chloride and a nanogram dose of dexamethasone. Pre-treatment and post-treatment MRI scans, physical therapy, and pain score data were then analyzed. Conclusions The MRI data for all the patients in this series showed significant positive changes. Probable bone formation was clear in the patients with osteonecrosis, and cartilage regeneration in the patients with osteoarthritis. Along with MRI evidence, the measured physical therapy outcomes, subjective pain, and functional status all improved. Autologous mesenchymal stem cell injection, in conjunction with hyaluronic acid, platelet rich plasma and calcium chloride, is a promising minimally invasive therapy for osteonecrosis of femoral head and, with low-dose dexamethasone, for osteoarthritis of human knees.

  15. Atmospheric sulphuric acid and aerosol formation: implications from atmospheric measurements for nucleation and early growth mechanisms

    Directory of Open Access Journals (Sweden)

    S.-L. Sihto

    2006-05-01

    Full Text Available We have investigated the formation and early growth of atmospheric secondary aerosol particles building on atmospheric measurements. The measurements were part of the QUEST 2 campaign which took place in spring 2003 in Hyytiälä (Finland. During the campaign numerous new aerosol particle formation events occurred of which 15 were accompanied by gaseous sulphuric acid measurements. Our detailed analysis of these 15 events is focussed on nucleation and early growth (to a diameter of 3 nm of fresh particles. It revealed that new particle formation seems to be a function of the gaseous sulphuric acid concentration to the power from one to two. The former would be consistent with the recently developed activation theory while the latter would be consistent with the kinetic nucleation theory. We find that some events are dominated by the activation mechanism and some are dominated by the kinetic mechanism. Inferred coefficients for the two nucleation mechanisms are correlated with the product of gaseous sulphuric acid and ammonia concentrations. This indicates that besides gaseous sulphuric acid also ammonia has a role in nucleation. Early growth of fresh particles to a diameter of 3 nm has a mean rate of 1.2 nm/h and is clearly correlated with the gaseous sulphuric acid concentration.

  16. Cutaneous Squamous Cell Carcinoma with Invasion through Ear Cartilage

    Directory of Open Access Journals (Sweden)

    Julie Boisen

    2016-01-01

    Full Text Available Cutaneous squamous cell carcinoma of the ear represents a high-risk tumor location with an increased risk of metastasis and local tissue invasion. However, it is uncommon for these cancers to invade through nearby cartilage. Cartilage invasion is facilitated by matrix metalloproteases, specifically collagenase 3. We present the unusual case of a 76-year-old man with an auricular squamous cell carcinoma that exhibited full-thickness perforation of the scapha cartilage. Permanent sections through the eroded cartilage confirmed tumor invasion extending to the posterior ear skin.

  17. The Application of Sheet Technology in Cartilage Tissue Engineering.

    Science.gov (United States)

    Ge, Yang; Gong, Yi Yi; Xu, Zhiwei; Lu, Yanan; Fu, Wei

    2016-04-01

    Cartilage tissue engineering started to act as a promising, even essential alternative method in the process of cartilage repair and regeneration, considering adult avascular structure has very limited self-renewal capacity of cartilage tissue in adults and a bottle-neck existed in conventional surgical treatment methods. Recent progressions in tissue engineering realized the development of more feasible strategies to treat cartilage disorders. Of these strategies, cell sheet technology has shown great clinical potentials in the regenerative areas such as cornea and esophagus and is increasingly considered as a potential way to reconstruct cartilage tissues for its non-use of scaffolds and no destruction of matrix secreted by cultured cells. Acellular matrix sheet technologies utilized in cartilage tissue engineering, with a sandwich model, can ingeniously overcome the drawbacks that occurred in a conventional acellular block, where cells are often blocked from migrating because of the non-nanoporous structure. Electrospun-based sheets with nanostructures that mimic the natural cartilage matrix offer a level of control as well as manipulation and make them appealing and widely used in cartilage tissue engineering. In this review, we focus on the utilization of these novel and promising sheet technologies to construct cartilage tissues with practical and beneficial functions. PMID:26414455

  18. A dual flow bioreactor with controlled mechanical stimulation for cartilage tissue engineering.

    Science.gov (United States)

    Spitters, Tim W G M; Leijten, Jeroen C H; Deus, Filipe D; Costa, Ines B F; van Apeldoorn, Aart A; van Blitterswijk, Clemens A; Karperien, Marcel

    2013-10-01

    In cartilage, tissue engineering bioreactors can create a controlled environment to study chondrocyte behavior under mechanical stimulation or produce chondrogenic grafts of clinically relevant size. Here we present a novel bioreactor that combines mechanical stimulation with a two compartment system through which nutrients can be supplied solely by diffusion from opposite sides of a tissue-engineered construct. This design is based on the hypothesis that creating gradients of nutrients, growth factors, and growth factor antagonists can aid in the generation of zonal tissue-engineered cartilage. Computational modeling predicted that the design facilitates the creation of a biologically relevant glucose gradient. This was confirmed by quantitative glucose measurements in cartilage explants. In this system, it is not only possible to create gradients of nutrients, but also of anabolic or catabolic factors. Therefore, the bioreactor design allows control over nutrient supply and mechanical stimulation useful for in vitro generation of cartilage constructs that can be used for the resurfacing of articulated joints or as a model for studying osteoarthritis disease progression.

  19. Characterization of sulphate scaling formation damage from laboratory measurements to predict well productivity decline

    Energy Technology Data Exchange (ETDEWEB)

    Bedrikovetsky, P.G.; Monteiro, R. [Universidade Estadual do Norte Fluminense (UENF), Macae, RJ (Brazil). Lab. de Engenharia e Exploracao de Petroleo (LENEP); Moraes, G.P. [Centro Federal de Educacao Tecnologica (CEFET), Macae, RJ (Brazil). Unidade de Ensino Descentralizada (UNED-Macae); Lopes Junior, R.P. [PETROBRAS, Macae, RJ (Brazil). Unidade de Negocios da Bacia de Campos; Rosario, F.F.; Bezerra, M.C. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    Barium sulphate scaling is a chronicle disaster during offshore waterflood project where injected and formation waters are incompatible, and their mixing causes salt precipitation. It was detected in several fields of Campos Basin. The mathematical model for sulphate precipitation contains two empirical parameters: the reaction kinetics coefficient that characterizes how fast the precipitation is going on, and the formation damage coefficient showing which permeability impairment the precipitation causes. Knowledge of these two parameters is essential for reliable prediction of the well productivity decline during sea/produced water injection. These parameters are empirical and depend on rock properties; therefore they should be determined from laboratory coreflood tests by forcing the injected and formation waters through rock. Despite these tests have been presented in numerous papers, there were no attempts to determine the model coefficients from laboratory data in order to perform the laboratory-data-based reservoir simulation. A new method for simultaneous determination of both coefficients from the coreflood data is developed. The method determines the kinetic coefficient from ion concentration measurements at the core effluent; then the formation damage coefficient is determined from the pressure drop measurements. The laboratory procedures are routine, the data are available in the literature. The method is based on inverse problem for reactive flow in rocks. The inverse solution is obtained from the exact quasi steady state concentration profile during coreflood. The proposed method furnishes unique values for two coefficients, and the solution is stable with respect to small perturbations of the measured values. The laboratory data on sulphate scaling by CENPES/PETROBRAS, Brazil, and Herriot-Watt University, UK, were treated, and the data were used for prediction of productivity decline in Campos Basin reservoir. The well behaviour forecast and history

  20. Sodium and T1rho MRI for molecular and diagnostic imaging of articular cartilage.

    Science.gov (United States)

    Borthakur, Arijitt; Mellon, Eric; Niyogi, Sampreet; Witschey, Walter; Kneeland, J Bruce; Reddy, Ravinder

    2006-11-01

    In this article, both sodium magnetic resonance (MR) and T1rho relaxation mapping aimed at measuring molecular changes in cartilage for the diagnostic imaging of osteoarthritis are reviewed. First, an introduction to structure of cartilage, its degeneration in osteoarthritis (OA) and an outline of diagnostic imaging methods in quantifying molecular changes and early diagnostic aspects of cartilage degeneration are described. The sodium MRI section begins with a brief overview of the theory of sodium NMR of biological tissues and is followed by a section on multiple quantum filters that can be used to quantify both bi-exponential relaxation and residual quadrupolar interaction. Specifically, (i) the rationale behind the use of sodium MRI in quantifying proteoglycan (PG) changes, (ii) validation studies using biochemical assays, (iii) studies on human OA specimens, (iv) results on animal models and (v) clinical imaging protocols are reviewed. Results demonstrating the feasibility of quantifying PG in OA patients and comparison with that in healthy subjects are also presented. The section concludes with the discussion of advantages and potential issues with sodium MRI and the impact of new technological advancements (e.g. ultra-high field scanners and parallel imaging methods). In the theory section on T1rho, a brief description of (i) principles of measuring T1rho relaxation, (ii) pulse sequences for computing T1rho relaxation maps, (iii) issues regarding radio frequency power deposition, (iv) mechanisms that contribute to T1rho in biological tissues and (v) effects of exchange and dipolar interaction on T1rho dispersion are discussed. Correlation of T1rho relaxation rate with macromolecular content and biomechanical properties in cartilage specimens subjected to trypsin and cytokine-induced glycosaminoglycan depletion and validation against biochemical assay and histopathology are presented. Experimental T1rho data from osteoarthritic specimens, animal models

  1. Direct measurements of the ozone formation potential from dairy cattle emissions using a transportable smog chamber

    Science.gov (United States)

    Howard, Cody J.; Yang, Wenli; Green, Peter G.; Mitloehner, Frank; Malkina, Irina L.; Flocchini, Robert G.; Kleeman, Michael J.

    Tropospheric ozone continues to be an air pollution problem in the United States, particularly in California, Texas, and across the eastern seaboard. The obvious sources of ozone precursors have been largely controlled over the past several decades, leading to the critical examination of secondary sources. In particular, California has new air quality rules addressing agricultural sources of ozone precursors, including dairy farms. Some recent estimates predict that dairy cattle are second only to on-road vehicles as a leading source of ozone precursor emissions in California's San Joaquin Valley. The objective of this work was to directly measure the ozone formation potential from dairy housing. A transportable "smog" chamber was constructed and validated using organic gases known to be present in dairy emissions. The ozone formation potential of emissions from eight non-lactating dairy cows and their fresh waste was then directly evaluated in the field at a completely enclosed cow corral on the campus of the University of California, Davis. The results demonstrate that the majority of the ozone formation is explained by ethanol (EtOH) in the emissions from the dairy cows, not by acetone as previously thought. Ozone formation potential is generally small, with cattle in California seems to be lower than previously estimated.

  2. Melanocortin 1 receptor-signaling deficiency results in an articular cartilage phenotype and accelerates pathogenesis of surgically induced murine osteoarthritis.

    Directory of Open Access Journals (Sweden)

    Julia Lorenz

    Full Text Available Proopiomelanocortin-derived peptides exert pleiotropic effects via binding to melanocortin receptors (MCR. MCR-subtypes have been detected in cartilage and bone and mediate an increasing number of effects in diathrodial joints. This study aims to determine the role of MC1-receptors (MC1 in joint physiology and pathogenesis of osteoarthritis (OA using MC1-signaling deficient mice (Mc1re/e. OA was surgically induced in Mc1re/e and wild-type (WT mice by transection of the medial meniscotibial ligament. Histomorphometry of Safranin O stained articular cartilage was performed with non-operated controls (11 weeks and 6 months and 4/8 weeks past surgery. µCT-analysis for assessing epiphyseal bone architecture was performed as a longitudinal study at 4/8 weeks after OA-induction. Collagen II, ICAM-1 and MC1 expression was analysed by immunohistochemistry. Mc1re/e mice display less Safranin O and collagen II stained articular cartilage area compared to WT prior to OA-induction without signs of spontaneous cartilage surface erosion. This MC1-signaling deficiency related cartilage phenotype persisted in 6 month animals. At 4/8 weeks after OA-induction cartilage erosions were increased in Mc1re/e knees paralleled by weaker collagen II staining. Prior to OA-induction, Mc1re/e mice do not differ from WT with respect to bone parameters. During OA, Mc1re/e mice developed more osteophytes and had higher epiphyseal bone density and mass. Trabecular thickness was increased while concomitantly trabecular separation was decreased in Mc1re/e mice. Numbers of ICAM-positive chondrocytes were equal in non-operated 11 weeks Mc1re/e and WT whereas number of positive chondrocytes decreased during OA-progression. Unchallenged Mc1re/e mice display smaller articular cartilage covered area without OA-related surface erosions indicating that MC1-signaling is critical for proper cartilage matrix integrity and formation. When challenged with OA, Mc1re/e mice develop a more

  3. Nitrogen Oxide Formation in the Electric Arc Furnace—Measurement and Modeling

    Science.gov (United States)

    Echterhof, Thomas; Pfeifer, Herbert

    2012-02-01

    In this article, the results of pilot electric arc furnace (EAF) trials and model calculations regarding the formation of NOx in an electric arc furnace are presented. The results of these investigations confirm that the conditions within the electric arc furnace are favorable for the formation of NOx. During pilot furnace trials, a notable influence of the electric parameters on the NOx formation could not be established. The importance of the influence of the furnace atmosphere, especially the O2 and CO content, could be ascertained clearly. Thermodynamic equilibrium calculations concerning the furnace atmosphere were conducted during the course of the investigations. The results clearly show that the chemical reaction kinetics have a considerable influence on the NOx concentrations measured in the off-gas of electric arc furnaces. Therefore, in addition to the equilibrium calculations, a reactor network model of the EAF was developed subsequently. Using this model, it was possible to reproduce phenomena such as the NOx peak at arc ignition as well as to calculate NOx concentrations, which match measurement data within an order of magnitude.

  4. Novel nano-rough polymers for cartilage tissue engineering

    Directory of Open Access Journals (Sweden)

    Balasundaram G

    2014-04-01

    Full Text Available Ganesan Balasundaram,1 Daniel M Storey,1 Thomas J Webster2,31Surfatek, Longmont, CO, USA; 2Department of Chemical Engineering, Northeastern University, Boston, MA, USA; 3Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Saudi ArabiaAbstract: This study presents an innovative method for creating a highly porous surface with nanoscale roughness on biologically relevant polymers, specifically polyurethane (PU and polycaprolactone (PCL. Nanoembossed polyurethane (NPU and nanoembossed polycaprolactone (NPCL were produced by the casting of PU and PCL over a plasma-deposited, spiky nanofeatured crystalline titanium (Ti surface. The variables used in the process of making the spiky Ti surface can be altered to change the physical properties of the spiky particles, and thus, the cast polymer substrate surface can be altered. The spiky Ti surface is reusable to produce additional nanopolymer castings. In this study, control plain PU and PCL polymers were produced by casting the polymers over a plain Ti surface (without spikes. All polymer surface morphologies were characterized using both scanning electron microscopy and atomic force microscopy, and their surface energies were measured using liquid contact angle measurements. The results revealed that both NPU and NPCL possessed a higher degree of nanometer surface roughness and higher surface energy compared with their respective unaltered polymers. Further, an in vitro study was carried out to determine chondrocyte (cartilage-producing cells functions on NPU and NPCL compared with on control plain polymers. Results of this study provided evidence of increased chondrocyte numbers on NPU and NPCL compared with their respective plain polymers after periods of up to 7 days. Moreover, the results provide evidence of greater intracellular protein production and collagen secretion by chondrocytes cultured on NPU and NPCL compared with control plain polymers. In summary

  5. Flavonoid Compound Icariin Activates Hypoxia Inducible Factor-1α in Chondrocytes and Promotes Articular Cartilage Repair.

    Science.gov (United States)

    Wang, Pengzhen; Zhang, Fengjie; He, Qiling; Wang, Jianqi; Shiu, Hoi Ting; Shu, Yinglan; Tsang, Wing Pui; Liang, Shuang; Zhao, Kai; Wan, Chao

    2016-01-01

    Articular cartilage has poor capability for repair following trauma or degenerative pathology due to avascular property, low cell density and migratory ability. Discovery of novel therapeutic approaches for articular cartilage repair remains a significant clinical need. Hypoxia is a hallmark for cartilage development and pathology. Hypoxia inducible factor-1alpha (HIF-1α) has been identified as a key mediator for chondrocytes to response to fluctuations of oxygen availability during cartilage development or repair. This suggests that HIF-1α may serve as a target for modulating chondrocyte functions. In this study, using phenotypic cellular screen assays, we identify that Icariin, an active flavonoid component from Herba Epimedii, activates HIF-1α expression in chondrocytes. We performed systemic in vitro and in vivo analysis to determine the roles of Icariin in regulation of chondrogenesis. Our results show that Icariin significantly increases hypoxia responsive element luciferase reporter activity, which is accompanied by increased accumulation and nuclear translocation of HIF-1α in murine chondrocytes. The phenotype is associated with inhibiting PHD activity through interaction between Icariin and iron ions. The upregulation of HIF-1α mRNA levels in chondrocytes persists during chondrogenic differentiation for 7 and 14 days. Icariin (10-6 M) increases the proliferation of chondrocytes or chondroprogenitors examined by MTT, BrdU incorporation or colony formation assays. Icariin enhances chondrogenic marker expression in a micromass culture including Sox9, collagen type 2 (Col2α1) and aggrecan as determined by real-time PCR and promotes extracellular matrix (ECM) synthesis indicated by Alcian blue staining. ELISA assays show dramatically increased production of aggrecan and hydroxyproline in Icariin-treated cultures at day 14 of chondrogenic differentiation as compared with the controls. Meanwhile, the expression of chondrocyte catabolic marker genes

  6. Flavonoid Compound Icariin Activates Hypoxia Inducible Factor-1α in Chondrocytes and Promotes Articular Cartilage Repair.

    Directory of Open Access Journals (Sweden)

    Pengzhen Wang

    Full Text Available Articular cartilage has poor capability for repair following trauma or degenerative pathology due to avascular property, low cell density and migratory ability. Discovery of novel therapeutic approaches for articular cartilage repair remains a significant clinical need. Hypoxia is a hallmark for cartilage development and pathology. Hypoxia inducible factor-1alpha (HIF-1α has been identified as a key mediator for chondrocytes to response to fluctuations of oxygen availability during cartilage development or repair. This suggests that HIF-1α may serve as a target for modulating chondrocyte functions. In this study, using phenotypic cellular screen assays, we identify that Icariin, an active flavonoid component from Herba Epimedii, activates HIF-1α expression in chondrocytes. We performed systemic in vitro and in vivo analysis to determine the roles of Icariin in regulation of chondrogenesis. Our results show that Icariin significantly increases hypoxia responsive element luciferase reporter activity, which is accompanied by increased accumulation and nuclear translocation of HIF-1α in murine chondrocytes. The phenotype is associated with inhibiting PHD activity through interaction between Icariin and iron ions. The upregulation of HIF-1α mRNA levels in chondrocytes persists during chondrogenic differentiation for 7 and 14 days. Icariin (10-6 M increases the proliferation of chondrocytes or chondroprogenitors examined by MTT, BrdU incorporation or colony formation assays. Icariin enhances chondrogenic marker expression in a micromass culture including Sox9, collagen type 2 (Col2α1 and aggrecan as determined by real-time PCR and promotes extracellular matrix (ECM synthesis indicated by Alcian blue staining. ELISA assays show dramatically increased production of aggrecan and hydroxyproline in Icariin-treated cultures at day 14 of chondrogenic differentiation as compared with the controls. Meanwhile, the expression of chondrocyte catabolic

  7. FT-IR Microspectroscopy of Rat Ear Cartilage.

    Directory of Open Access Journals (Sweden)

    Benedicto de Campos Vidal

    Full Text Available Rat ear cartilage was studied using Fourier transform-infrared (FT-IR microspectroscopy to expand the current knowledge which has been established for relatively more complex cartilage types. Comparison of the FT-IR spectra of the ear cartilage extracellular matrix (ECM with published data on articular cartilage, collagen II and 4-chondroitin-sulfate standards, as well as of collagen type I-containing dermal collagen bundles (CBs with collagen type II, was performed. Ear cartilage ECM glycosaminoglycans (GAGs were revealed histochemically and as a reduction in ECM FT-IR spectral band heights (1140-820 cm-1 after testicular hyaluronidase digestion. Although ear cartilage is less complex than articular cartilage, it contains ECM components with a macromolecular orientation as revealed using polarization microscopy. Collagen type II and GAGs, which play a structural role in the stereo-arrangement of the ear cartilage, contribute to its FT-IR spectrum. Similar to articular cartilage, ear cartilage showed that proteoglycans add a contribution to the collagen amide I spectral region, a finding that does not recommend this region for collagen type II quantification purposes. In contrast to articular cartilage, the symmetric stretching vibration of -SO3- groups at 1064 cm-1 appeared under-represented in the FT-IR spectral profile of ear cartilage. Because the band corresponding to the asymmetric stretching vibration of -SO3- groups (1236-1225 cm-1 overlapped with that of amide III bands, it is not recommended for evaluation of the -SO3- contribution to the FT-IR spectrum of the ear cartilage ECM. Instead, a peak (or shoulder at 1027-1016 cm-1 could be better considered for this intent. Amide I/amide II ratios as calculated here and data from the literature suggest that protein complexes of the ear cartilage ECM are arranged with a lower helical conformation compared to pure collagen II. The present results could motivate further studies on this tissue

  8. FT-IR Microspectroscopy of Rat Ear Cartilage.

    Science.gov (United States)

    Vidal, Benedicto de Campos; Mello, Maria Luiza S

    2016-01-01

    Rat ear cartilage was studied using Fourier transform-infrared (FT-IR) microspectroscopy to expand the current knowledge which has been established for relatively more complex cartilage types. Comparison of the FT-IR spectra of the ear cartilage extracellular matrix (ECM) with published data on articular cartilage, collagen II and 4-chondroitin-sulfate standards, as well as of collagen type I-containing dermal collagen bundles (CBs) with collagen type II, was performed. Ear cartilage ECM glycosaminoglycans (GAGs) were revealed histochemically and as a reduction in ECM FT-IR spectral band heights (1140-820 cm-1) after testicular hyaluronidase digestion. Although ear cartilage is less complex than articular cartilage, it contains ECM components with a macromolecular orientation as revealed using polarization microscopy. Collagen type II and GAGs, which play a structural role in the stereo-arrangement of the ear cartilage, contribute to its FT-IR spectrum. Similar to articular cartilage, ear cartilage showed that proteoglycans add a contribution to the collagen amide I spectral region, a finding that does not recommend this region for collagen type II quantification purposes. In contrast to articular cartilage, the symmetric stretching vibration of -SO3- groups at 1064 cm-1 appeared under-represented in the FT-IR spectral profile of ear cartilage. Because the band corresponding to the asymmetric stretching vibration of -SO3- groups (1236-1225 cm-1) overlapped with that of amide III bands, it is not recommended for evaluation of the -SO3- contribution to the FT-IR spectrum of the ear cartilage ECM. Instead, a peak (or shoulder) at 1027-1016 cm-1 could be better considered for this intent. Amide I/amide II ratios as calculated here and data from the literature suggest that protein complexes of the ear cartilage ECM are arranged with a lower helical conformation compared to pure collagen II. The present results could motivate further studies on this tissue under

  9. On the Incorporation of Metallicity Data into Star Formation History Measurements from Resolved Stellar Populations

    CERN Document Server

    Dolphin, Andrew E

    2016-01-01

    The combination of spectroscopic stellar metallicities and resolved star color-magnitude diagrams (CMDs) has the potential to constrain the entire star formation and chemical enrichment history (SFH) of a galaxy better than fitting CMDs alone (as is most common in SFH studies using resolved stellar populations). In this paper, two approaches for incorporating external metallicity information into color-magnitude diagram fitting techniques are presented. Overall, the joint fitting of metallicity and CMD information can increase the precision on measured age-metallicity relationships and star formation rates by ~10% over CMD fitting alone. However, systematics in stellar isochrones and mismatches between spectroscopic and photometric metallicity determinations can reduce the accuracy of the recovered SFHs. I present a simple mitigation of these systematics that can reduce the amplitude of these systematics to the level obtained from CMD fitting alone, while ensuring the age-metallicity relationship is consisten...

  10. A spectroscopic measure of the star-formation rate density in dwarf galaxies at z~1

    CERN Document Server

    Davies, G T; Glazebrook, Karl; Bower, Richard; Baldry, I K; Balogh, Michael; Hau, G K T; Li, I H; McCarthy, P; Savaglio, S

    2009-01-01

    We use a K-selected (22.5 < K_AB < 24.0) sample of dwarf galaxies (8.4 < log(M*/Msun) < 10) at 0.89measure their contribution to the global star-formation rate density (SFRD), as inferred from their [OII] flux. By comparing with [OII]-based studies of higher stellar mass galaxies, we robustly measure a turnover in the [OII] luminosity density at a stellar mass of M~10^10 Msun. By comparison with the [OII]-based SFRD measured from the Sloan Digital Sky Survey we confirm that, while the SFRD of the lowest-mass galaxies changes very little with time, the SFRD of more massive galaxies evolves strongly, such that they dominate the SFRD at z = 1.

  11. Preplanned correction of enophthalmos using diced cartilage grafts.

    Science.gov (United States)

    Lee, J

    2000-01-01

    A simple technique for correcting post-traumatic enophthalmos is presented. Autogenous costal cartilage was chopped into small pieces and used to fill up the medial orbital wall defect in five patients. The measured degrees of enophthalmos ranged from 2 to 4 mm, and 3-5. 5 ml of filler material was introduced into the periorbital space. A conservative approach via upper and lower eyelid incisions was used. It was found that 1.37-1.5 ml of graft material results in 1 mm advancement of globe position. This correlation appears to be a useful treatment guideline for medial orbital wall blow-out fractures. Transient diplopia developed in three cases, but settled within 4 months. There were no other major sequelae after the operation. The follow-up period ranged from 8 months to 3 years. The improved appearance and the stable results confirm the validity of this approach. PMID:10657444

  12. Effect of osteoporosis and intervertebral disc degeneration on endplate cartilage injury in rats

    Institute of Scientific and Technical Information of China (English)

    Lei Wang; Wei Cui; Jean Pierre Kalala; Tom Van Hoof; Bao-Ge Liu

    2014-01-01

    Objective:To investigate the effect of osteoporosis and intervertebral disc degeneration on the endplate cartilage injury in rats.Methods:A total of48 femaleSpragueDawley rats(3 months) were randomly divided intoGroupsA,B,C andD with12 rats in each group.Osteoporosis and intervertebral disc degeneration composite model, simple degeneration model and simple osteoporosis model were prepared inGroupsA,B andC respectively.After modeling, four rats of each group at12th,18th and24th week were sacrificed.Intervertebral height of cervical vertebra C6/C7 was measured.Micro-CT was used to image the endplate of cephalic and caudal cartilage atC6/C7 intervertebral disc.Abraded area rate ofC6 caudal andC7 cephalic cartilage endplate was calculated, and thenC6/C7 intervertebral disc was routinely embedded and sectioned, stained with safraninO to observe histological changes microscopically.Results:At12,18 and 24 weeks, intervertebral disc height ofC6/C7 were(0.58±0.09) mm,(0.53±0.04) mm and(0.04±0.06) mm inGroupA rats,(0.55±0.05) mm,(0.52±0.07) mm and(0.07±0.05) mm inGroupB rats.At24th week, intervertebral disc height ofGroupA rats was significantly lower than that ofGroupB rats (P0.05).At12 and18 weeks, the abraded rate ofC6 caudal andC7 cephalic cartilage endplate inGroupA rats were significantly higher than that inGroupsB,C andD rats(P0.05).Microscopic observation ofCT showed that ventral defects inC6 caudal orC7 cephalic cartilage endplate inGroupsA andB appeared after12 weeks of modeling;obvious cracks were found in front of theC6 andC7 vertebral body, and cartilage defect shown the trend of "repairing" at18 and24 weeks after modeling.Conclusions:Intervertebral disc degeneration and osteoporosis can cause damage to the cartilage endplate.Co-existence of these two factors can induce more serious damage to the endplate, which has possitive correlation with intervertebral disc degeneration.Osteoporosis plays a certain role in intervertebral disc degeneration process, and

  13. Promotion of the articular cartilage proteoglycan degradation by T-2 toxin and selenium protective effect

    Institute of Scientific and Technical Information of China (English)

    Si-yuan LI; Jun-ling CAO; Zhong-li SHI; Jing-hong CHEN; Zeng-tie ZHANG; Clare E. HUGHES; Bruce CATERSON

    2008-01-01

    Objective: To identify the relationship between T-2 toxin and Kashin-Beck disease (KBD), the effects of T-2 toxin on aggrecan metabolism in human chondrocytes and cartilage were investigated in vitro. Methods: Chondrocytes were isolated from human articular cartilage and cultured in vitro. Hyaluronic acid (HA), soluble CD44 (sCD44), IL-1β and TNF-α levels in supernatants were measured by enzyme-linked immunosorbent assay (ELISA). CD44 content in chondrocyte membrane was determined by flow cytometry (FCM). CD44, hyaluronic acid synthetase-2 (HAS-2) and aggrecanases mRNA levels in chondrocytes were determined using reverse transcription polymerase chain reaction (RT-PCR). Immunocytochemical method was used to investigate expressions of BC-13, 3-B-3(-) and 2-B-6 epitopes in the cartilage reconstructed in vitro. Results: T-2 toxin inhibited CD44, HAS-2, and aggrecan mRNA expressions, but promoted aggrecanase-2 mRNA expression. Meanwhile, CD44 expression was found to be the lowest in the chondrocytes cultured with T-2 toxin and the highest in control plus selenium group. In addition,ELISA results indicated that there were higher sCD44, IL-1β and TNF-α levels in T-2 toxin group. Similarly, higher HA levels were also observed in T-2 toxin group using radioimmunoprecipitation assay (RIPA). Furthermore, using monoclonal antibodies BC-13, 3-B-3 and 2-B-6, strong positive immunostaining was found in the reconstructed cartilage cultured with T-2 toxin, whereas no positive staining or very weak staining was observed in the cartilage cultured without T-2 toxin. Selenium could partly inhibit the effects of T-2 toxin above. Conclusion: T-2 toxin could inhibit aggrecan synthesis, promote aggrecanases and pro-inflammatory cytokines production, and consequently induce aggrecan degradation in chondrocytes. These will perturb metabolism balance between aggrecan synthesis and degradation in cartilage, inducing aggrecan loss in the end, which may be the initiation of the cartilage

  14. Quantitative versus semiquantitative MR imaging of cartilage in blood-induced arthritic ankles: preliminary findings

    Energy Technology Data Exchange (ETDEWEB)

    Doria, Andrea S. [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto, ON (Canada); University of Toronto, Department of Medical Imaging, Toronto, ON (Canada); Zhang, Ningning [Children' s Hospital, Department of Radiology, Beijing (China); Lundin, Bjorn [Skaane University Hospital and Lund University, University Hospital of Lund, Center for Medical Imaging and Physiology, Lund (Sweden); Hilliard, Pamela [The Hospital for Sick Children, Department of Rehabilitation Services, Toronto, ON (Canada); Man, Carina; Weiss, Ruth; Detzler, Garry [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto, ON (Canada); Blanchette, Victor [The Hospital for Sick Children, Department of Hematology, Toronto, ON (Canada); Moineddin, Rahim [Family and Community Medicine, Department of Public Health, Toronto, ON (Canada); Eckstein, Felix [Paracelsus Medical University, Institute of Anatomy and Musculoskeletal Research, Salzburg (Austria); Chondrometrics GmbH, Ainring (Germany); Sussman, Marshall S. [University of Toronto, Department of Medical Imaging, Toronto, ON (Canada); University Health Network, Department of Medical Imaging, Toronto, ON (Canada)

    2014-05-15

    Recent advances in hemophilia prophylaxis have raised the need for accurate noninvasive methods for assessment of early cartilage damage in maturing joints to guide initiation of prophylaxis. Such methods can either be semiquantitative or quantitative. Whereas semiquantitative scores are less time-consuming to be performed than quantitative methods, they are prone to subjective interpretation. To test the feasibility of a manual segmentation and a quantitative methodology for cross-sectional evaluation of articular cartilage status in growing ankles of children with blood-induced arthritis, as compared with a semiquantitative scoring system and clinical-radiographic constructs. Twelve boys, 11 with hemophilia (A, n = 9; B, n = 2) and 1 with von Willebrand disease (median age: 13; range: 6-17), underwent physical examination and MRI at 1.5 T. Two radiologists semiquantitatively scored the MRIs for cartilage pathology (surface erosions, cartilage loss) with blinding to clinical information. An experienced operator applied a validated quantitative 3-D MRI method to determine the percentage area of denuded bone (dAB) and the cartilage thickness (ThCtAB) in the joints' MRIs. Quantitative and semiquantitative MRI methods and clinical-radiographic constructs (Hemophilia Joint Health Score [HJHS], Pettersson radiograph scores) were compared. Moderate correlations were noted between erosions and dAB (r = 0.62, P = 0.03) in the talus but not in the distal tibia (P > 0.05). Whereas substantial to high correlations (r range: 0.70-0.94, P < 0.05) were observed between erosions, cartilage loss, HJHS and Pettersson scores both at the distal tibia and talus levels, moderate/borderline substantial (r range: 0.55-0.61, P < 0.05) correlations were noted between dAB/ThCtAB and clinical-radiographic constructs. Whereas the semiquantitative method of assessing cartilage status is closely associated with clinical-radiographic scores in cross-sectional studies of blood

  15. Age-Independent Cartilage Generation for Synovium-Based Autologous Chondrocyte Implantation.

    Science.gov (United States)

    Hunziker, Ernst B; Lippuner, Kurt; Keel, Marius J B; Shintani, Nahoko

    2015-07-01

    The articular cartilage layer of synovial joints is commonly lesioned by trauma or by a degenerative joint disease. Attempts to repair the damage frequently involve the performance of autologous chondrocyte implantation (ACI). Healthy cartilage must be first removed from the joint, and then, on a separate occasion, following the isolation of the chondrocytes and their expansion in vitro, implanted within the lesion. The disadvantages of this therapeutic approach include the destruction of healthy cartilage-which may predispose the joint to osteoarthritic degeneration-the necessarily restricted availability of healthy tissue, the limited proliferative capacity of the donor cells-which declines with age-and the need for two surgical interventions. We postulated that it should be possible to induce synovial stem cells, which are characterized by high, age-independent, proliferative and chondrogenic differentiation capacities, to lay down cartilage within the outer juxtasynovial space after the transcutaneous implantation of a carrier bearing BMP-2 in a slow-release system. The chondrocytes could be isolated on-site and immediately used for ACI. To test this hypothesis, Chinchilla rabbits were used as an experimental model. A collagenous patch bearing BMP-2 in a slow-delivery vehicle was sutured to the inner face of the synovial membrane. The neoformed tissue was excised 5, 8, 11 and 14 days postimplantation for histological and histomorphometric analyses. Neoformed tissue was observed within the outer juxtasynovial space already on the 5th postimplantation day. It contained connective and adipose tissues, and a central nugget of growing cartilage. Between days 5 and 14, the absolute volume of cartilage increased, attaining a value of 12 mm(3) at the latter juncture. Bone was deposited in measurable quantities from the 11th day onwards, but owing to resorption, the net volume did not exceed 1.5 mm(3) (14th day). The findings confirm our hypothesis. The quantity of

  16. Computational model for the analysis of cartilage and cartilage tissue constructs

    Science.gov (United States)

    Smith, David W.; Gardiner, Bruce S.; Davidson, John B.; Grodzinsky, Alan J.

    2013-01-01

    We propose a new non-linear poroelastic model that is suited to the analysis of soft tissues. In this paper the model is tailored to the analysis of cartilage and the engineering design of cartilage constructs. The proposed continuum formulation of the governing equations enables the strain of the individual material components within the extracellular matrix (ECM) to be followed over time, as the individual material components are synthesized, assembled and incorporated within the ECM or lost through passive transport or degradation. The material component analysis developed here naturally captures the effect of time-dependent changes of ECM composition on the deformation and internal stress states of the ECM. For example, it is shown that increased synthesis of aggrecan by chondrocytes embedded within a decellularized cartilage matrix initially devoid of aggrecan results in osmotic expansion of the newly synthesized proteoglycan matrix and tension within the structural collagen network. Specifically, we predict that the collagen network experiences a tensile strain, with a maximum of ~2% at the fixed base of the cartilage. The analysis of an example problem demonstrates the temporal and spatial evolution of the stresses and strains in each component of a self-equilibrating composite tissue construct, and the role played by the flux of water through the tissue. PMID:23784936

  17. Computational model for the analysis of cartilage and cartilage tissue constructs.

    Science.gov (United States)

    Smith, David W; Gardiner, Bruce S; Davidson, John B; Grodzinsky, Alan J

    2016-04-01

    We propose a new non-linear poroelastic model that is suited to the analysis of soft tissues. In this paper the model is tailored to the analysis of cartilage and the engineering design of cartilage constructs. The proposed continuum formulation of the governing equations enables the strain of the individual material components within the extracellular matrix (ECM) to be followed over time, as the individual material components are synthesized, assembled and incorporated within the ECM or lost through passive transport or degradation. The material component analysis developed here naturally captures the effect of time-dependent changes of ECM composition on the deformation and internal stress states of the ECM. For example, it is shown that increased synthesis of aggrecan by chondrocytes embedded within a decellularized cartilage matrix initially devoid of aggrecan results in osmotic expansion of the newly synthesized proteoglycan matrix and tension within the structural collagen network. Specifically, we predict that the collagen network experiences a tensile strain, with a maximum of ~2% at the fixed base of the cartilage. The analysis of an example problem demonstrates the temporal and spatial evolution of the stresses and strains in each component of a self-equilibrating composite tissue construct, and the role played by the flux of water through the tissue. Copyright © 2013 John Wiley & Sons, Ltd. PMID:23784936

  18. Chondrocytic ephrin B2 promotes cartilage destruction by osteoclasts in endochondral ossification.

    Science.gov (United States)

    Tonna, Stephen; Poulton, Ingrid J; Taykar, Farzin; Ho, Patricia W M; Tonkin, Brett; Crimeen-Irwin, Blessing; Tatarczuch, Liliana; McGregor, Narelle E; Mackie, Eleanor J; Martin, T John; Sims, Natalie A

    2016-02-15

    The majority of the skeleton arises by endochondral ossification, whereby cartilaginous templates expand and are resorbed by osteoclasts then replaced by osteoblastic bone formation. Ephrin B2 is a receptor tyrosine kinase expressed by osteoblasts and growth plate chondrocytes that promotes osteoblast differentiation and inhibits osteoclast formation. We investigated the role of ephrin B2 in endochondral ossification using Osx1Cre-targeted gene deletion. Neonatal Osx1Cre.Efnb2(Δ/Δ) mice exhibited a transient osteopetrosis demonstrated by increased trabecular bone volume with a high content of growth plate cartilage remnants and increased cortical thickness, but normal osteoclast numbers within the primary spongiosa. Osteoclasts at the growth plate had an abnormal morphology and expressed low levels of tartrate-resistant acid phosphatase; this was not observed in more mature bone. Electron microscopy revealed a lack of sealing zones and poor attachment of Osx1Cre.Efnb2(Δ/Δ) osteoclasts to growth plate cartilage. Osteoblasts at the growth plate were also poorly attached and impaired in their ability to deposit osteoid. By 6 months of age, trabecular bone mass, osteoclast morphology and osteoid deposition by Osx1Cre.Efnb2(Δ/Δ) osteoblasts were normal. Cultured chondrocytes from Osx1Cre.Efnb2(Δ/Δ) neonates showed impaired support of osteoclastogenesis but no significant change in Rankl (Tnfsf11) levels, whereas Adamts4 levels were significantly reduced. A population of ADAMTS4(+) early hypertrophic chondrocytes seen in controls was absent from Osx1Cre.Efnb2(Δ/Δ) neonates. This suggests that Osx1Cre-expressing cells, including hypertrophic chondrocytes, are dependent on ephrin B2 for their production of cartilage-degrading enzymes, including ADAMTS4, and this might be required for attachment of osteoclasts and osteoblasts to the cartilage surface during endochondral ossification.

  19. Of mice, men and elephants: the relation between articular cartilage thickness and body mass.

    Directory of Open Access Journals (Sweden)

    Jos Malda

    Full Text Available Mammalian articular cartilage serves diverse functions, including shock absorption, force transmission and enabling low-friction joint motion. These challenging requirements are met by the tissue's thickness combined with its highly specific extracellular matrix, consisting of a glycosaminoglycan-interspersed collagen fiber network that provides a unique combination of resilience and high compressive and shear resistance. It is unknown how this critical tissue deals with the challenges posed by increases in body mass. For this study, osteochondral cores were harvested post-mortem from the central sites of both medial and lateral femoral condyles of 58 different mammalian species ranging from 25 g (mouse to 4000 kg (African elephant. Joint size and cartilage thickness were measured and biochemical composition (glycosaminoclycan, collagen and DNA content and collagen cross-links densities were analyzed. Here, we show that cartilage thickness at the femoral condyle in the mammalian species investigated varies between 90 µm and 3000 µm and bears a negative allometric relationship to body mass, unlike the isometric scaling of the skeleton. Cellular density (as determined by DNA content decreases with increasing body mass, but gross biochemical composition is remarkably constant. This however need not affect life-long performance of the tissue in heavier mammals, due to relatively constant static compressive stresses, the zonal organization of the tissue and additional compensation by joint congruence, posture and activity pattern of larger mammals. These findings provide insight in the scaling of articular cartilage thickness with body weight, as well as in cartilage biochemical composition and cellularity across mammalian species. They underscore the need for the use of appropriate in vivo models in translational research aiming at human applications.

  20. Enhanced mechanical properties of thermosensitive chitosan hydrogel by silk fibers for cartilage tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Mirahmadi, Fereshteh [Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); National Cell Bank of Iran, Pasteur Institute of Iran, Tehran (Iran, Islamic Republic of); Tafazzoli-Shadpour, Mohammad, E-mail: Tafazoli@aut.ac.ir [Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Shokrgozar, Mohammad Ali, E-mail: mashokrgozar@pasteur.ac.ir [National Cell Bank of Iran, Pasteur Institute of Iran, Tehran (Iran, Islamic Republic of); Bonakdar, Shahin [National Cell Bank of Iran, Pasteur Institute of Iran, Tehran (Iran, Islamic Republic of)

    2013-12-01

    Articular cartilage has limited repair capability following traumatic injuries and current methods of treatment remain inefficient. Reconstructing cartilage provides a new way for cartilage repair and natural polymers are often used as scaffold because of their biocompatibility and biofunctionality. In this study, we added degummed chopped silk fibers and electrospun silk fibers to the thermosensitive chitosan/glycerophosphate hydrogels to reinforce two hydrogel constructs which were used as scaffold for hyaline cartilage regeneration. The gelation temperature and gelation time of hydrogel were analyzed by the rheometer and vial tilting method. Mechanical characterization was measured by uniaxial compression, indentation and dynamic mechanical analysis assay. Chondrocytes were then harvested from the knee joint of the New Zealand white rabbits and cultured in constructs. The cell proliferation, viability, production of glycosaminoglycans and collagen type II were assessed. The results showed that mechanical properties of the hydrogel were significantly enhanced when a hybrid with two layers of electrospun silk fibers was made. The results of GAG and collagen type II in cell-seeded scaffolds indicate support of the chondrogenic phenotype for chondrocytes with a significant increase in degummed silk fiber–hydrogel composite for GAG content and in two-layer electrospun fiber–hydrogel composite for Col II. It was concluded that these two modified scaffolds could be employed for cartilage tissue engineering. - Highlights: • Chitosan hydrogel composites fabricated by two forms of silk fiber • Silk fibers provide structural support for the hydrogel matrix. • The mechanical properties of hydrogel significantly improved by associating with silk. • Production of GAG and collagen type II was demonstrated within the scaffolds.

  1. Management of the droopy tip: a comparison of three alar cartilage-modifying techniques.

    Science.gov (United States)

    Foda, Hossam M T

    2003-10-01

    The droopy tip is a common nasal deformity in which the tip is inferiorly rotated. Five hundred consecutive rhinoplasty cases were studied to assess the incidence and causes of the droopy tip deformity and to evaluate the role of three alar cartilage-modifying techniques--lateral crural steal, lateral crural overlay, and tongue in groove--in correcting such a deformity. The external rhinoplasty approach was used in all cases. Only one of the three alar cartilage-modifying techniques was used in each case, and the degree of tip rotation and projection was measured both preoperatively and postoperatively. The incidence of droopy tip was 72 percent, and the use of an alar cartilage-modifying technique was required in 85 percent of these cases to achieve the desired degree of rotation. The main causes of droopy tip included inferiorly oriented alar cartilages (85 percent), overdeveloped scrolls of upper lateral cartilages (73 percent), high anterior septal angle (65 percent), and thick skin of the nasal lobule (56 percent). The lateral crural steal technique increased nasal tip rotation and projection, the lateral crural overlay technique increased tip rotation and decreased tip projection, and the tongue-in-groove technique increased tip rotation without significantly changing the amount of projection. The lateral crural overlay technique resulted in the highest degrees of rotation, followed by the lateral crural steal and finally the tongue-in-groove technique. According to these results, the lateral crural steal technique is best indicated in cases with droopy underprojected nasal tip, the lateral crural overlay technique in cases of droopy overprojected nasal tip, and the tongue-in-groove technique in cases where the droopy nasal tip is associated with an adequate amount of projection. PMID:14504527

  2. The Effect of Altered Loading on Mandibular Condylar Cartilage

    Science.gov (United States)

    Kaul, Raman; O’Brien, Mara H.; Dutra, Eliane; Lima, Alexandro; Utreja, Achint; Yadav, Sumit

    2016-01-01

    Objective The purpose of this study was to delineate the cellular, mechanical and morphometric effects of altered loading on the mandibular condylar cartilage (MCC) and subchondral bone. We hypothesized that altered loading will induce differentiation of cells by accelerating the lineage progression of the MCC. Materials and Methods Four-week-old male Dkk3 XCol2A1XCol10A1 mice were randomly divided into two groups: (1) Loaded-Altered loading of MCC was induced by forced mouth opening using a custom-made spring; (2) Control-served as an unloaded group. Mice were euthanized and flow cytometery based cell analysis, micro-CT, gene expression analysis, histology and morphometric measurements were done to assess the response. Results Our flow cytometery data showed that altered loading resulted in a significant increase in a number of Col2a1-positive (blue) and Col10a1-positive (red) expressing cells. The gene expression analysis showed significant increase in expression of BMP2, Col10a1 and Sox 9 in the altered loading group. There was a significant increase in the bone volume fraction and trabecular thickness, but a decrease in the trabecular spacing of the subchondral bone with the altered loading. Morphometric measurements revealed increased mandibular length, increased condylar length and increased cartilage width with altered loading. Our histology showed increased mineralization/calcification of the MCC with 5 days of loading. An unexpected observation was an increase in expression of tartrate resistant acid phosphatase activity in the fibrocartilaginous region with loading. Conclusion Altered loading leads to mineralization of fibrocartilage and drives the lineage towards differentiation/maturation. PMID:27472059

  3. Measurements of the Suitability of Large Rock Salt Formations for Radio Detection of High Energy Neutrinos

    CERN Document Server

    Gorham, P W; Odian, A; Williams, D; Besson, D; Frichter, G; Tantawi, S G; Gorham, Peter; Saltzberg, David; Odian, Allen; Williams, Dawn; Besson, David; Frichter, George; Tantawi, Sami

    2002-01-01

    We have investigated the possibility that large rock salt formations might be suitable as target masses for detection of neutrinos of energies about 10 PeV and above. In neutrino interactions at these energies, the secondary electromagnetic cascade produces a coherent radio pulse well above ambient thermal noise via the Askaryan effect. We describe measurements of radio-frequency attenuation lengths and ambient thermal noise in two salt formations. Measurements in the Waste Isolation Pilot Plant (WIPP), located in an evaporite salt bed in Carlsbad, NM yielded short attenuation lengths, 3-7 m over 150-300 MHz. However, measurements at United Salt's Hockley mine, located in a salt dome near Houston, Texas yielded attenuation lengths in excess of 250 m at similar frequencies. We have also analyzed early ground-penetrating radar data at Hockley mine and have found additional evidence for attenuation lengths in excess of several hundred meters at 440 MHz. We conclude that salt domes, which may individually contain...

  4. Permeability Estimation of Grosmont Formation, Alberta, Canada by Statistically Combining Well-logs and Core Measurements

    Science.gov (United States)

    Choi, J.; Keehm, Y.

    2011-12-01

    Permeability estimation in carbonate reservoirs is quite challenging since they are very heterogeneous. Moreover, the amount of core measurement data is commonly limited. In this paper, we present permeability maps for Grosmont formation in Canada with very limited permeability data, using bi-variated probability density function (porosity and permeability) conditioned to geological information. Grosmont formation consists of four units: Lower Grosmont (LG); Upper Grosmont (UG1); Upper Grosmont 2 (UG2); and Upper Grosmont 3 (UG3). From the previous studies, UG2 and UG3 are more promising reservoir units since they have larger porosity and permeability with vuggy pores and fractures by diagenesis (dolomitization and karstification). Thus, we applied our method to these two units. We first investigated core measurement data (porosity and permeability) and compared them to local geological aspects, such as the degree of diagenesis and vicinity of unconformity. Then we could divide the study area into 6 groups, and we established a bivariated probability density function (pdf) for each group and each unit (total of 12 pdfs) with core measurements of porosity and permeability. In the next step, we created porosity maps using well-log data for UG2 and UG3. The final step is to generate permeability maps for UG2 and UG3 by drawing a permeability value from the bivariated pdf conditioned to porosity. The final results show more realistic permeability maps for Grosmont formation when compared to conventional kriging results. Moreover, the strengths of this approach is (1) that it can use geological information and (2) that it can handle the variability of permeability, which can be naturally occurred in carbonate reservoirs. Acknowledgement: This work was supported by the Energy Resources R&D program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Knowledge Economy (No. 2008RER11P0430302009).

  5. Atmospheric sulphuric acid and aerosol formation: implications from atmospheric measurements for nucleation and early growth mechanisms

    Directory of Open Access Journals (Sweden)

    S.-L. Sihto

    2006-01-01

    Full Text Available We have investigated the formation and early growth of atmospheric secondary aerosol particles building on atmospheric measurements. The measurements were part of the QUEST 2 campaign which took place in spring 2003 in Hyytiälä (Finland. During the campaign numerous aerosol particle formation events occurred of which 15 were accompanied by gaseous sulphuric acid measurements. Our detailed analysis of these 15 events is focussed on nucleation and early growth (to a diameter of 3 nm of fresh particles. It revealed that new particle formation seems to be a function of the gaseous sulphuric acid concentration to the power from one to two when the time delay between the sulphuric acid and particle number concentration is taken into account. From the time delay the growth rates of freshly nucleated particles from 1 nm to 3 nm were determined. The mean growth rate was 1.2 nm/h and it was clearly correlated with the gaseous sulphuric acid concentration. We tested two nucleation mechanisms – recently proposed cluster activation and kinetic type nucleation – as possible candidates to explain the observed dependences, and determined experimental nucleation coefficients. We found that some events are dominated by the activation mechanism and some by the kinetic mechanism. Inferred coefficients for the two nucleation mechanisms are the same order of magnitude as chemical reaction coefficients in the gas phase and they correlate with the product of gaseous sulphuric acid and ammonia concentrations. This indicates that besides gaseous sulphuric acid also ammonia has a role in nucleation.

  6. The Application of Polysaccharide Biocomposites to Repair Cartilage Defects

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2014-01-01

    Full Text Available Owing to own nature of articular cartilage, it almost has no self-healing ability once damaged. Despite lots of restore technologies having been raised in the past decades, no repair technology has smoothly substituted for damaged cartilage using regenerated cartilage tissue. The approach of tissue engineering opens a door to successfully repairing articular cartilage defects. For instance, grafting of isolated chondrocytes has huge clinical potential for restoration of cartilage tissue and cure of chondral injury. In this paper, SD rats are used as subjects in the experiments, and they are classified into three groups: natural repair (group A, hyaluronic acid repair (group B, and polysaccharide biocomposites repair (hyaluronic acid hydrogel containing chondrocytes, group C. Through the observation of effects of repairing articular cartilage defects, we concluded that cartilage repair effect of polysaccharide biocomposites was the best at every time point, and then the second best was hyaluronic acid repair; both of them were better than natural repair. Polysaccharide biocomposites have good biodegradability and high histocompatibility and promote chondrocytes survival, reproduction, and spliting. Moreover, polysaccharide biocomposites could not only provide the porous network structure but also carry chondrocytes. Consequently hyaluronic acid-based polysaccharide biocomposites are considered to be an ideal biological material for repairing articular cartilage.

  7. Combined role of type IX collagen and cartilage oligomeric matrix protein in cartilage matrix assembly: Cartilage oligomeric matrix protein counteracts type IX collagen-induced limitation of cartilage collagen fibril growth in mouse chondrocyte cultures

    NARCIS (Netherlands)

    Blumbach, K.; Bastiaansen-Jenniskens, Y.M.; Groot, J. de; Paulsson, M.; Osch, G.J.V.M. van; Zaucke, F.

    2009-01-01

    Objective. Defects in the assembly and composition of cartilage extracellular matrix are likely to result in impaired matrix integrity and increased susceptibility to cartilage degeneration. The aim of this study was to determine the functional interaction of the collagen fibril-associated proteins

  8. THIONIN STAINING OF PARAFFIN AND PLASTIC EMBEDDED SECTIONS OF CARTILAGE

    NARCIS (Netherlands)

    BULSTRA, SK; DRUKKER, J; KUIJER, R; BUURMAN, WA; VANDERLINDEN, AJ

    1993-01-01

    The usefulness of thionin for staining cartilage sections embedded in glycol methacrylate (GMA) and the effect of decalcification on cartilage sections embedded in paraffin and GMA were assessed. Short decalcification periods using 5% formic acid or 10% EDTA did not influence the staining properties

  9. A Novel Approach to Stimulate Cartilage Repair: Targeting Collagen Turnover

    NARCIS (Netherlands)

    Y.M. Bastiaansen-Jenniskens (Yvonne Maria)

    2009-01-01

    textabstractOA is a complex disease of which the ethiopathology is not completely known and therapies to repair cartilage are still under investigation. The increase of collagen type II expression in osteoarthritic cartilage suggests an activated repair mechanism that is however ineffective in repai

  10. Poroelasticity of Cartilage at the Nanoscale

    OpenAIRE

    Nia, Hadi Tavakoli; Han, Lin; Li, Yang; Ortiz, Christine; Grodzinsky, Alan

    2011-01-01

    Atomic-force-microscopy-based oscillatory loading was used in conjunction with finite element modeling to quantify and predict the frequency-dependent mechanical properties of the superficial zone of young bovine articular cartilage at deformation amplitudes, δ, of ∼15 nm; i.e., at macromolecular length scales. Using a spherical probe tip (R ∼ 12.5 μm), the magnitude of the dynamic complex indentation modulus, |E∗|, and phase angle, ϕ, between the force and tip displacement sinusoids, were me...

  11. Cartilage Aggrecan Can Undergo Self-Adhesion

    OpenAIRE

    Han, Lin; Dean, Delphine; Daher, Laura A.; Grodzinsky, Alan J.; Ortiz, Christine

    2008-01-01

    Here it is reported that aggrecan, the highly negatively charged macromolecule in the cartilage extracellular matrix, undergoes Ca2+-mediated self-adhesion after static compression even in the presence of strong electrostatic repulsion in physiological-like solution conditions. Aggrecan was chemically end-attached onto gold-coated planar silicon substrates and gold-coated microspherical atomic force microscope probe tips (end radius R ≈ 2.5 μm) at a density (∼40 mg/mL) that simulates physiolo...

  12. Evaluation of a lithium formate EPR dosimetry system for dose measurements around Ir-192 brachytherapy sources

    OpenAIRE

    Antonovic, Laura; Gustafsson, Håkan; Alm Carlsson, Gudrun; Carlsson Tedgren, Åsa

    2009-01-01

    A dosimetry system using lithium formate monohydrate (HCO2Li center dot H2O) as detector material and electron paramagnetic resonance (EPR) spectroscopy for readout has been used to measure absorbed dose distributions around clinical Ir-192 sources. Cylindrical tablets with diameter of 4.5 mm, height of 4.8 mm, and density of 1.26 g/cm(3) were manufactured. Homogeneity test and calibration of the dosimeters were performed in a 6 MV photon beam. Ir-192 irradiations were performed in a PMMA pha...

  13. A method for measuring the formation times of light flashes in scintillator films

    CERN Document Server

    Astvatsaturov, R G; Harutunyan, V N; Eganov, V S

    1999-01-01

    A method is proposed to estimate experimentally the formation times of light flashes in different types of scintillators. For illustration of the method a series of measurements with three following types of polystyrene (PS)-based scintillator films has been conducted: PS+1% 4'-vinyl-3-hydroxyflavone (4V3HF); PS+2% para-terphenyl (PTP)+0.007%4, 4'-distyrylbiphenyl( DSBP); PS+1% hydroxyflavone (3HF). The values obtained for the delays of light flashes were respectively: (0.2+-0.14) ns, (0.6+-0.17) ns and (0.9+-0.18) ns.

  14. Stem Cell-assisted Approaches for Cartilage Tissue Engineering.

    Science.gov (United States)

    Park, In-Kyu; Cho, Chong-Su

    2010-05-01

    The regeneration of damaged articular cartilage remains challenging due to its poor intrinsic capacity for repair. Tissue engineering of articular cartilage is believed to overcome the current limitations of surgical treatment by offering functional regeneration in the defect region. Selection of proper cell sources and ECM-based scaffolds, and incorporation of growth factors or mechanical stimuli are of primary importance to successfully produce artificial cartilage for tissue repair. When designing materials for cartilage tissue engineering, biodegradability and biocompatibility are the key factors in selecting material candidates, for either synthetic or natural polymers. The unique environment of cartilage makes it suitable to use a hydrogel with high water content in the cross-linked or thermosensitive (injectable) form. Moreover, design of composite scaffolds from two polymers with complementary physicochemical and biological properties has been explored to provide residing chondrocytes with a combination of the merits that each component contributes.

  15. Epiphyseal and Physeal Cartilage: Normal Gadolinium-enhanced MR Imaging

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    To evaluate the normal appearance of epiphyseal and physeal cartilage on Gadolinium (Gd)-enhanced MR imaging. The appearance and enhancement ratios of 20 proximal and distal femoral epiphyses in 10 normal piglets were analyzed on Gd-enhanced MR images. The correlation of the MR imaging appearance with corresponding histological findings of immature epiphyses was examined. Our results showed that Gd-enhanced MRI could differentiate the differences in enhancement between physeal and epiphyseal cartilage and show vascular canals within the epiphyseal cartilage. Enhanced ratios in the physeal were greater than those in the epiphyseal cartilage (P<0.005). It is concluded that Gd-enhanced MR imaging reveals epiphyseal vascular canals and shows difference in enhancement of physeal and epiphyseal cartilage.

  16. REGENERATION OF ARTICULAR CARTILAGE UNDER THE IMPLANTATION OF BONE MATRIX

    Directory of Open Access Journals (Sweden)

    Yuri M. Iryanov, Nikolay A. Kiryanov, Olga V. Dyuriagina , Tatiana Yu. Karaseva, Evgenii A. Karasev

    2015-07-01

    Full Text Available Background: The damage or loss of articular cartilage is costly medical problem. The purpose of this work – morphological analysis of reparative chondrogenesis when implanted in the area of the knee joint cartilage of granulated mineralized bone matrix. Material and Methods: The characteristic features of the knee cartilage regeneration studied experimentally in pubertal Wistar rats after modeling a marginal perforated defect and implantation of granulated mineralized bone matrix obtained according to original technology without heat and demineralizing processing into the injury zone. Results: This biomaterial established to have pronounced chondro- and osteoinductive properties, and to provide prolonged activation of reparative process, accelerated organotypical remodeling and restoration of the articular cartilage injured. Conclusion: The data obtained demonstrate the efficacy of МВМ in clinical practice for the treatment of diseases and injuries of the articular cartilage.

  17. An update on risk factors for cartilage loss in knee osteoarthritis assessed using MRI-based semiquantitative grading methods

    Energy Technology Data Exchange (ETDEWEB)

    Alizai, Hamza [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); Aspetar Orthopaedic and Sports Medicine Hospital, Doha (Qatar); University of Texas Health Science Center at San Antonio, Department of Radiology, San Antonio, TX (United States); Roemer, Frank W. [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); Aspetar Orthopaedic and Sports Medicine Hospital, Doha (Qatar); University of Erlangen-Nuremberg, Department of Radiology, Erlangen (Germany); Hayashi, Daichi [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); Aspetar Orthopaedic and Sports Medicine Hospital, Doha (Qatar); Yale University School of Medicine, Department of Radiology, Bridgeport Hospital, Bridgeport, CT (United States); Crema, Michel D. [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); Aspetar Orthopaedic and Sports Medicine Hospital, Doha (Qatar); Hospital do Coracao and Teleimagem, Department of Radiology, Sao Paulo (Brazil); Felson, David T. [Boston University School of Medicine, Clinical Epidemiology Research and Training Unit, Boston, MA (United States); Guermazi, Ali [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); Aspetar Orthopaedic and Sports Medicine Hospital, Doha (Qatar); Boston Medical Center, Boston, MA (United States)

    2014-11-07

    Arthroscopy-based semiquantitative scoring systems such as Outerbridge and Noyes' scores were the first to be developed for the purpose of grading cartilage defects. As magnetic resonance imaging (MRI) became available faor evaluation of the osteoarthritic knee joint, these systems were adapted for use with MRI. Later on, grading methods such as the Whole Organ Magnetic Resonance Score, the Boston-Leeds Osteoarthritis Knee Score and the MRI Osteoarthritis Knee Score were designed specifically for performing whole-organ assessment of the knee joint structures, including cartilage. Cartilage grades on MRI obtained with these scoring systems represent optimal outcome measures for longitudinal studies, and are designed to enhance understanding of the knee osteoarthritis disease process. The purpose of this narrative review is to describe cartilage assessment in knee osteoarthritis using currently available MRI-based semiquantitative whole-organ scoring systems, and to provide an update on the risk factors for cartilage loss in knee osteoarthritis as assessed with these scoring systems. (orig.)

  18. An update on risk factors for cartilage loss in knee osteoarthritis assessed using MRI-based semiquantitative grading methods

    International Nuclear Information System (INIS)

    Arthroscopy-based semiquantitative scoring systems such as Outerbridge and Noyes' scores were the first to be developed for the purpose of grading cartilage defects. As magnetic resonance imaging (MRI) became available faor evaluation of the osteoarthritic knee joint, these systems were adapted for use with MRI. Later on, grading methods such as the Whole Organ Magnetic Resonance Score, the Boston-Leeds Osteoarthritis Knee Score and the MRI Osteoarthritis Knee Score were designed specifically for performing whole-organ assessment of the knee joint structures, including cartilage. Cartilage grades on MRI obtained with these scoring systems represent optimal outcome measures for longitudinal studies, and are designed to enhance understanding of the knee osteoarthritis disease process. The purpose of this narrative review is to describe cartilage assessment in knee osteoarthritis using currently available MRI-based semiquantitative whole-organ scoring systems, and to provide an update on the risk factors for cartilage loss in knee osteoarthritis as assessed with these scoring systems. (orig.)

  19. Measuring star formation with resolved observations: the test case of M 33

    Science.gov (United States)

    Boquien, M.; Calzetti, D.; Aalto, S.; Boselli, A.; Braine, J.; Buat, V.; Combes, F.; Israel, F.; Kramer, C.; Lord, S.; Relaño, M.; Rosolowsky, E.; Stacey, G.; Tabatabaei, F.; van der Tak, F.; van der Werf, P.; Verley, S.; Xilouris, M.

    2015-06-01

    Context. Measuring star formation on a local scale is important to constrain star formation laws. It is not clear yet, however, whether and how the measure of star formation is affected by the spatial scale at which a galaxy is observed. Aims: We wish to understand the impact of the resolution on the determination of the spatially resolved star formation rate (SFR) and other directly associated physical parameters such as the attenuation. Methods: We carried out a multi-scale, pixel-by-pixel study of the nearby galaxy M 33. Assembling FUV, Hα, 8 μm, 24 μm, 70 μm, and 100 μm maps, we have systematically compared the emission in individual bands with various SFR estimators from a resolution of 33 pc to 2084 pc. Results: There are strong, scale-dependent, discrepancies of up to a factor 3 between monochromatic SFR estimators and Hα+24 μm. The scaling factors between individual IR bands and the SFR show a strong dependence on the spatial scale and on the intensity of star formation. Finally, strong variations of the differential reddening between the nebular emission and the stellar continuum are seen, depending on the specific SFR (sSFR) and on the resolution. At the finest spatial scales, there is little differential reddening at high sSFR. The differential reddening increases with decreasing sSFR. At the coarsest spatial scales the differential reddening is compatible with the canonical value found for starburst galaxies. Conclusions: Our results confirm that monochromatic estimators of the SFR are unreliable at scales smaller than 1 kpc. Furthermore, the extension of local calibrations to high-redshift galaxies presents non-trivial challenges because the properties of these systems may be poorly known. The maps (FITS files) and the data cube used in this article are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/578/A8

  20. Genipin-crosslinked cartilage-derived matrix as a scaffold for human adipose-derived stem cell chondrogenesis.

    Science.gov (United States)

    Cheng, Nai-Chen; Estes, Bradley T; Young, Tai-Horng; Guilak, Farshid

    2013-02-01

    Autologous cell-based tissue engineering using three-dimensional scaffolds holds much promise for the repair of cartilage defects. Previously, we reported on the development of a porous scaffold derived solely from native articular cartilage, which can induce human adipose-derived stem cells (ASCs) to differentiate into a chondrogenic phenotype without exogenous growth factors. However, this ASC-seeded cartilage-derived matrix (CDM) contracts over time in culture, which may limit certain clinical applications. The present study aimed to investigate the ability of chemical crosslinking using a natural biologic crosslinker, genipin, to prevent scaffold contraction while preserving the chondrogenic potential of CDM. CDM scaffolds were crosslinked in various genipin concentrations, seeded with ASCs, and then cultured for 4 weeks to evaluate the influence of chemical crosslinking on scaffold contraction and ASC chondrogenesis. At the highest crosslinking degree of 89%, most cells failed to attach to the scaffolds and resulted in poor formation of a new extracellular matrix. Scaffolds with a low crosslinking density of 4% experienced cell-mediated contraction similar to our original report on noncrosslinked CDM. Using a 0.05% genipin solution, a crosslinking degree of 50% was achieved, and the ASC-seeded constructs exhibited no significant contraction during the culture period. Moreover, expression of cartilage-specific genes, synthesis, and accumulation of cartilage-related macromolecules and the development of mechanical properties were comparable to the original CDM. These findings support the potential use of a moderately (i.e., approximately one-half of the available lysine or hydroxylysine residues being crosslinked) crosslinked CDM as a contraction-free biomaterial for cartilage tissue engineering.

  1. Radiological observation of determination of sex by costal cartilage calcification

    International Nuclear Information System (INIS)

    The difference of patterns of costal cartilage calcification in male and female had been first described by Fischer in 1955. Thereafter several reports were published, but specific clinical significance was not found. During the period from January, 1978 to December, 1978, we, in the Department of Radiology, Jeonbug National University, studied 2164 cases that showed the entire 12 pairs of ribs. Among these we detected 1494 cases of costal cartilage calcification and frequent sites of calcification. Patterns of costal cartilage calcification were classified into six groups- type l: central, type II: marginal, type III: junctional type, type IV: railroad, type V: diffuse, type VI: mixed. Results are as follows; 1. In a total of 2164 cases, calcification of costal cartilage was present in 1494 cases(69.0%). Of 1181 males 780 cases(66.0%) showed calcification, and of 983 females 714 cases (72.6%) showed calcification. 2. In 439 cases of males, except for 341 cases that showed calcification within the first costal cartilage, patterns of costal cartilage calcification were as follows: marginal type in 265 cases (60.4%), junctional type in 134 cases (30.5%), mixed type in 21 cases (0.5%), central type in 17 cases(3.8%), and railroad type in 2 cases (0.5%). Diffuse type was not present. 3. In 492 cases of females, except of 222 cases that showed calcification within the first costal cartilage, patterns of costal cartilage calcification were as follows; central type in 336 cases (68.3%), junctional type in 94 cases(19.1%), mixed type in 24 cases (4.9%), railroad type in 19 cases (3.9%), and diffuse type in 14 cases (2.8%). 4. When central calcification was observed, predictive value to female was 94.7%. When marginal calcification was observed, predictive value to male was 987.4%. 5. Males frequently showed calcification in upper costal cartilages, and females in lower costal cartilages.

  2. Radiological observation of determination of sex by costal cartilage calcification

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Shin Hwa; Won, Jong Jin; Rhee, Song Joo; Moon, Moo Chang; Oh, Jong Hyun; Choi, Ki Chul [Jeonbug National University College of Medicine, Jeonjju (Korea, Republic of)

    1979-12-15

    The difference of patterns of costal cartilage calcification in male and female had been first described by Fischer in 1955. Thereafter several reports were published, but specific clinical significance was not found. During the period from January, 1978 to December, 1978, we, in the Department of Radiology, Jeonbug National University, studied 2164 cases that showed the entire 12 pairs of ribs. Among these we detected 1494 cases of costal cartilage calcification and frequent sites of calcification. Patterns of costal cartilage calcification were classified into six groups- type l: central, type II: marginal, type III: junctional type, type IV: railroad, type V: diffuse, type VI: mixed. Results are as follows; 1. In a total of 2164 cases, calcification of costal cartilage was present in 1494 cases(69.0%). Of 1181 males 780 cases(66.0%) showed calcification, and of 983 females 714 cases (72.6%) showed calcification. 2. In 439 cases of males, except for 341 cases that showed calcification within the first costal cartilage, patterns of costal cartilage calcification were as follows: marginal type in 265 cases (60.4%), junctional type in 134 cases (30.5%), mixed type in 21 cases (0.5%), central type in 17 cases(3.8%), and railroad type in 2 cases (0.5%). Diffuse type was not present. 3. In 492 cases of females, except of 222 cases that showed calcification within the first costal cartilage, patterns of costal cartilage calcification were as follows; central type in 336 cases (68.3%), junctional type in 94 cases(19.1%), mixed type in 24 cases (4.9%), railroad type in 19 cases (3.9%), and diffuse type in 14 cases (2.8%). 4. When central calcification was observed, predictive value to female was 94.7%. When marginal calcification was observed, predictive value to male was 987.4%. 5. Males frequently showed calcification in upper costal cartilages, and females in lower costal cartilages.

  3. Biochemical effects on long-term frozen human costal cartilage

    International Nuclear Information System (INIS)

    Currently, the progresses on treatment of musculoskeletal diseases with the evolving of artificial implants and the success of tissue transplantation between genetically different individuals have conducted to an increase in radiosterilization. Regarding to tissue transplantation, it is essential to have sterile tissue and many tissue banks use radiosterilization as an effective method to sterilize these tissues. However, high doses of ionizing radiation and the preservation method may induce structural modifications in the tissues, as degradation of structural scaffold, decreasing its mechanical properties. Particularly, cartilage have been preserved in high concentrations of glycerol or deep-frozen at -70 degree C for storage after radiosterilization. Therefore, it is important to study the modifications induced in cartilage by preservation methods and by radiosterilization to determine the appropriated parameters for high quality of human allografts. Costal cartilages were obtained from cadaveric donors and were frozen at -20 degree C for 2 years long in order to compare with previous studies for fresh, deep-frozen and glycerolised cartilages. The mechanical tests were carried out in a universal testing machine until sample failure. According our results, there is no significant statistical difference between stress at break of fresh, long-term - 20 degree C frozen cartilages and deep-frozen cartilage. This early result suggests, regarding to tensile property, that long-term - 20 degree C frozen cartilages corresponds to glycerolised costal cartilages irradiated with 25 kGy or deep-frozen cartilages irradiated with 25 and 50 kGy. Thus, this long-term frozen cartilages may be used for tissue banks, but more studies about effects of ionizing radiation are necessary. (author)

  4. Biochemical effects on long-term frozen human costal cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Santin, Stefany P.; Martinho Junior, Antonio C.; Yoshito, Daniele; Soares, Fernando A.N.; Mathor, Monica B., E-mail: mathor@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Currently, the progresses on treatment of musculoskeletal diseases with the evolving of artificial implants and the success of tissue transplantation between genetically different individuals have conducted to an increase in radiosterilization. Regarding to tissue transplantation, it is essential to have sterile tissue and many tissue banks use radiosterilization as an effective method to sterilize these tissues. However, high doses of ionizing radiation and the preservation method may induce structural modifications in the tissues, as degradation of structural scaffold, decreasing its mechanical properties. Particularly, cartilage have been preserved in high concentrations of glycerol or deep-frozen at -70 degree C for storage after radiosterilization. Therefore, it is important to study the modifications induced in cartilage by preservation methods and by radiosterilization to determine the appropriated parameters for high quality of human allografts. Costal cartilages were obtained from cadaveric donors and were frozen at -20 degree C for 2 years long in order to compare with previous studies for fresh, deep-frozen and glycerolised cartilages. The mechanical tests were carried out in a universal testing machine until sample failure. According our results, there is no significant statistical difference between stress at break of fresh, long-term - 20 degree C frozen cartilages and deep-frozen cartilage. This early result suggests, regarding to tensile property, that long-term - 20 degree C frozen cartilages corresponds to glycerolised costal cartilages irradiated with 25 kGy or deep-frozen cartilages irradiated with 25 and 50 kGy. Thus, this long-term frozen cartilages may be used for tissue banks, but more studies about effects of ionizing radiation are necessary. (author)

  5. MT1-MMP and type II collagen specify skeletal stem cells and their bone and cartilage progeny

    DEFF Research Database (Denmark)

    Szabova, L.; Yamada, S.S.; Wimer, H.;

    2009-01-01

    Skeletal formation is dependent on timely recruitment of skeletal stem cells and their ensuing synthesis and remodeling of the major fibrillar collagens, type I collagen and type II collagen, in bone and cartilage tissues during development and postnatal growth. Loss of the major collagenolytic...... activity associated with the membrane-type 1 matrix metalloproteinase (MT1-MMP) results in disrupted skeletal development and growth in both cartilage and bone, where MT1-MMP is required for pericellular collagen dissolution. We show here that reconstitution of MT1-MMP activity in the type II collagen......-expressing cells of the skeleton rescues not only diminished chondrocyte proliferation, but surprisingly, also results in amelioration of the severe skeletal dysplasia associated with MT1-MMP deficiency through enhanced bone formation. Consistent with this increased bone formation, type II collagen was identified...

  6. Measurements of organic gases during aerosol formation events in the boreal forest atmosphere during QUEST

    Directory of Open Access Journals (Sweden)

    K. Sellegri

    2004-08-01

    Full Text Available Biogenic VOCs are important in the growth and possibly also in the formation of atmospheric aerosol particles. In this work, we present 10 min-time resolution measurements of organic trace gases at Hyytiälä, Finland during March 2002. The measurements were part of the project QUEST (Quantification of Aerosol Nucleation in the European Boundary Layer and took place during a two-week period when nucleation events occurred with various intensities nearly every day. Using a ground-based Chemical Ionization Mass Spectrometer (CIMS instrument, the following trace gases were detected: acetone, TMA, DMA, mass 68 amu (candidate=isoprene, monoterpenes, Methyl Vinyl Ketone (MVK and Methacrolein (MaCR, cis-3-hexenyl acetate and MonoTerpene Oxidation Products (MTOP. For all of them except for the amines, we present daily variations during different classes of event days, and non-event days. Isoprene, monoterpenes, MVK+MaCR, cis-3-hexenyl acetate and MTOP are found to show significant correlations with the condensational sink (CS, which indicates that a fraction of these compounds are participating to the growth of the nucleated particles and generally secondary organic aerosol formation. Moreover, the terpene oxidation products (TOP (MVK, MaCR and MTOP show a higher ratio to the CS on event days compared to non-event days, indicating that their abundance relative to the surface of aerosol available is higher on nucleation days.

  7. Formation of an artificial blood vessel: adhesion force measurements with optical tweezers

    Science.gov (United States)

    Knoener, Gregor; Campbell, Julie H.; Heckenberg, Norman R.; Rubinsztein-Dunlop, Halina

    2004-10-01

    We are investigating the formation of a tissue capsule around a foreign body. This tissue capsule can be used as an autologous graft for the replacement of diseased blood vessels or for bypass surgery. The graft is grown in the peritoneal cavity of the recipient and the formation starts with the adhesion of cells to the foreign body. We identify the cell type and measure the adhesion of these cells to foreign materials using optical tweezers. Cell adhesion to macroscopic samples and microspheres is investigated. No difference in the adhesion force was measurable for polyethylene, silicon and Tygon on a scale accessible to optical tweezers. The density of adherent cells was found to vary strongly, being highest on polyethylene. The mean rupture forces for cell-microsphere adhesion ranged from 24 to 39 pN and changed upon preadsorption of bovine serum albumin. For plain microspheres, the highest mean rupture force was found for PMMA, which also showed the highest adhesion probability for the cell-microsphere interaction.

  8. Supporting the Health Quality Measures Format in i2b2.

    Science.gov (United States)

    Klann, Jeffrey G; Murphy, Shawn N

    2013-01-01

    The Health Quality Measures Format (HQMF) is an HL7 standard for expressing computable queries of clinical data. It is becoming increasingly consequential for both quality measurement and population health research. A variety of national leadership is involved in its development and deployment, including the Meaningful Use incentive program, the Query Health initiative, the Joint Commission, the National Quality Forum (NQF), and the Food and Drug Administration. Here we analyze the structure of HQMF and apply this to computation of HQMF on Informatics for Integrating Biology and the Bedside (i2b2). i2b2 is a widely used, modular, open-source clinical research data repository. We implement a translator to convert between HQMF and i2b2-XML format that covers the subset of HQMF supported in i2b2-XML, which will be expanded in the next release of i2b2. This translator is part of the freely-available reference implementation of the QueryHealth initiative. PMID:24303250

  9. Composite scaffolds for cartilage tissue engineering.

    Science.gov (United States)

    Moutos, Franklin T; Guilak, Farshid

    2008-01-01

    Tissue engineering remains a promising therapeutic strategy for the repair or regeneration of diseased or damaged tissues. Previous approaches have typically focused on combining cells and bioactive molecules (e.g., growth factors, cytokines and DNA fragments) with a biomaterial scaffold that functions as a template to control the geometry of the newly formed tissue, while facilitating the attachment, proliferation, and differentiation of embedded cells. Biomaterial scaffolds also play a crucial role in determining the functional properties of engineered tissues, including biomechanical characteristics such as inhomogeneity, anisotropy, nonlinearity or viscoelasticity. While single-phase, homogeneous materials have been used extensively to create numerous types of tissue constructs, there continue to be significant challenges in the development of scaffolds that can provide the functional properties of load-bearing tissues such as articular cartilage. In an attempt to create more complex scaffolds that promote the regeneration of functional engineered tissues, composite scaffolds comprising two or more distinct materials have been developed. This paper reviews various studies on the development and testing of composite scaffolds for the tissue engineering of articular cartilage, using techniques such as embedded fibers and textiles for reinforcement, embedded solid structures, multi-layered designs, or three-dimensionally woven composite materials. In many cases, the use of composite scaffolds can provide unique biomechanical and biological properties for the development of functional tissue engineering scaffolds.

  10. Arthroscopic ultrasound technique for simultaneous quantitative assessment of articular cartilage and subchondral bone: an in vitro and in vivo feasibility study.

    Science.gov (United States)

    Liukkonen, J; Hirvasniemi, J; Joukainen, A; Penttilä, P; Virén, T; Saarakkala, S; Kröger, H; Jurvelin, J S; Töyräs, J

    2013-08-01

    Traditional arthroscopic examination is subjective and poorly reproducible. Recently, we introduced an arthroscopic ultrasound method for quantitative diagnostics of cartilage lesions. Here we describe our investigation of the feasibility of ultrasound arthroscopy for simultaneous measurements of articular cartilage and subchondral bone. Human osteochondral samples (n = 13) were imaged using a clinical 9-MHz ultrasound system. Ultrasound reflection coefficients (R, IRC), the ultrasound roughness index (URI) and the apparent integrated backscattering coefficient (AIB) were determined for both tissues. Mechanical testing, histologic analyses and micro-scale computed tomography imaging were the reference methods. Ultrasound arthroscopies were conducted on two patients. The ultrasound reflection coefficient correlated with the Mankin score and Young's modulus of cartilage (|r| > 0.56, p 0.70, p 0.59, p 0.65, p < 0.05). Arthroscopic ultrasound examination provided diagnostically valuable information on cartilage and subchondral bone in vivo. PMID:23743098

  11. Demonstration of immunogenic keratan sulphate in commercial chondroitin 6-sulphate from shark cartilage. Implications for ELISA assays

    DEFF Research Database (Denmark)

    Møller, H J; Møller-Pedersen, T; Damsgaard, T E;

    1995-01-01

    The prototype monoclonal keratan sulphate (KS) antibody 5D4 that is widely used for detection of KS in tissues and biological fluids reacts strongly with commercial low grade shark cartilage chondroitin 6-sulphate. Characterization of the immunogenic material by chondroitinase ABC digestion, ELISA...... inhibition studies, immunoblotting and HPLC analyses confirmed the presence of substantial amounts of KS, probably as a large proteoglycan (> 120 kDa). Commercial and heterogenic glycosaminoglycan preparations therefore must be used with great caution in immunological analyses. On the other hand the shark...... cartilage chondroitin 6-sulphate is an easy accessible source of immunogenic KS that can be used as a reference standard and as coating antigen in KS-ELISAs. The concentration of immunogenic KS in synovial fluid measured with an ELISA based solely on reagents of shark cartilage chondroitin 6-sulphate...

  12. Comparative studies of type X collagen expression in normal and rachitic chicken epiphyseal cartilage

    OpenAIRE

    1989-01-01

    The levels of type X collagen in mineralizing normal chicken epiphyses and nonmineralizing rachitic chicken tibial epiphyses were measured and compared. Qualitative immunoperoxidase studies with anti-chick type X collagen monoclonal antibodies on sections from normal and rachitic cartilage demonstrated that the type X collagen levels in rachitic growth plates are reduced. Northern hybridization of mRNA and biosynthetic studies have confirmed that type X collagen synthesis in rickets is also d...

  13. Quantifying Quadriceps Muscle Strength in Patients With ACL Injury, Focal Cartilage Lesions, and Degenerative Meniscus Tears

    Science.gov (United States)

    Eitzen, Ingrid; Grindem, Hege; Nilstad, Agnethe; Moksnes, Håvard; Risberg, May Arna

    2016-01-01

    Background: Reduced quadriceps strength influences knee function and increases the risk of knee osteoarthritis. Thus, it is of significant clinical relevance to precisely quantify strength deficits in patients with knee injuries. Purpose: To evaluate isokinetic concentric quadriceps muscle strength torque values, assessed both from peak torque and at specific knee flexion joint angles, in patients with anterior cruciate ligament (ACL) injury, focal cartilage lesions, and degenerative meniscus tears. Study Design: Cohort study; Level of evidence, 3. Methods: Data were synthesized from patients included in 3 previously conducted research projects: 2 prospective cohort studies and 1 randomized controlled trial. At the time of inclusion, all patients were candidates for surgery. Isokinetic concentric quadriceps muscle strength measurements (60 deg/s) were performed at baseline (preoperative status) and after a period of progressive supervised exercise therapy (length of rehabilitation period: 5 weeks for ACL injury, 12 weeks for cartilage lesions and degenerative meniscus). Outcome measures were peak torque and torque at specific knee flexion joint angles from 20° to 70°. All patients had unilateral injuries, and side-to-side deficits were calculated. For comparisons between and within groups, we utilized 1-way analysis of variance and paired t tests, respectively. Results: In total, 250 patients were included. At baseline, cartilage patients had the most severe deficit (39.7% ± 24.3%; P torque was consistently measured at 60° of knee flexion, whereas the largest mean deficits were measured at 30° at baseline and 70° at retest for the ACL group, at 70° at baseline and retest for the degenerative meniscus group, and at 60° at baseline and at 50° at retest for the cartilage group. Conclusion: This study underlines the importance of including torque at specific knee flexion joint angles from isokinetic assessments to identify the most severe quadriceps muscle

  14. Polyester type polyHIPE scaffolds with an interconnected porous structure for cartilage regeneration

    Science.gov (United States)

    Naranda, Jakob; Sušec, Maja; Maver, Uroš; Gradišnik, Lidija; Gorenjak, Mario; Vukasović, Andreja; Ivković, Alan; Rupnik, Marjan Slak; Vogrin, Matjaž; Krajnc, Peter

    2016-06-01

    Development of artificial materials for the facilitation of cartilage regeneration remains an important challenge in orthopedic practice. Our study investigates the potential for neocartilage formation within a synthetic polyester scaffold based on the polymerization of high internal phase emulsions. The fabrication of polyHIPE polymer (PHP) was specifically tailored to produce a highly porous (85%) structure with the primary pore size in the range of 50–170 μm for cartilage tissue engineering. The resulting PHP scaffold was proven biocompatible with human articular chondrocytes and viable cells were observed within the materials as evaluated using the Live/Dead assay and histological analysis. Chondrocytes with round nuclei were organized into multicellular layers on the PHP surface and were observed to grow approximately 300 μm into the scaffold interior. The accumulation of collagen type 2 was detected using immunohistochemistry and chondrogenic specific genes were expressed with favorable collagen type 2 to 1 ratio. In addition, PHP samples are biodegradable and their baseline mechanical properties are similar to those of native cartilage, which enhance chondrocyte cell growth and proliferation.

  15. Polyester type polyHIPE scaffolds with an interconnected porous structure for cartilage regeneration.

    Science.gov (United States)

    Naranda, Jakob; Sušec, Maja; Maver, Uroš; Gradišnik, Lidija; Gorenjak, Mario; Vukasović, Andreja; Ivković, Alan; Rupnik, Marjan Slak; Vogrin, Matjaž; Krajnc, Peter

    2016-01-01

    Development of artificial materials for the facilitation of cartilage regeneration remains an important challenge in orthopedic practice. Our study investigates the potential for neocartilage formation within a synthetic polyester scaffold based on the polymerization of high internal phase emulsions. The fabrication of polyHIPE polymer (PHP) was specifically tailored to produce a highly porous (85%) structure with the primary pore size in the range of 50-170 μm for cartilage tissue engineering. The resulting PHP scaffold was proven biocompatible with human articular chondrocytes and viable cells were observed within the materials as evaluated using the Live/Dead assay and histological analysis. Chondrocytes with round nuclei were organized into multicellular layers on the PHP surface and were observed to grow approximately 300 μm into the scaffold interior. The accumulation of collagen type 2 was detected using immunohistochemistry and chondrogenic specific genes were expressed with favorable collagen type 2 to 1 ratio. In addition, PHP samples are biodegradable and their baseline mechanical properties are similar to those of native cartilage, which enhance chondrocyte cell growth and proliferation. PMID:27340110

  16. Polyester type polyHIPE scaffolds with an interconnected porous structure for cartilage regeneration

    Science.gov (United States)

    Naranda, Jakob; Sušec, Maja; Maver, Uroš; Gradišnik, Lidija; Gorenjak, Mario; Vukasović, Andreja; Ivković, Alan; Rupnik, Marjan Slak; Vogrin, Matjaž; Krajnc, Peter

    2016-06-01

    Development of artificial materials for the facilitation of cartilage regeneration remains an important challenge in orthopedic practice. Our study investigates the potential for neocartilage formation within a synthetic polyester scaffold based on the polymerization of high internal phase emulsions. The fabrication of polyHIPE polymer (PHP) was specifically tailored to produce a highly porous (85%) structure with the primary pore size in the range of 50-170 μm for cartilage tissue engineering. The resulting PHP scaffold was proven biocompatible with human articular chondrocytes and viable cells were observed within the materials as evaluated using the Live/Dead assay and histological analysis. Chondrocytes with round nuclei were organized into multicellular layers on the PHP surface and were observed to grow approximately 300 μm into the scaffold interior. The accumulation of collagen type 2 was detected using immunohistochemistry and chondrogenic specific genes were expressed with favorable collagen type 2 to 1 ratio. In addition, PHP samples are biodegradable and their baseline mechanical properties are similar to those of native cartilage, which enhance chondrocyte cell growth and proliferation.

  17. Cartilage Tissue Engineering with Silk Fibroin Scaffolds Fabricated by Indirect Additive Manufacturing Technology

    Directory of Open Access Journals (Sweden)

    Chih-Hao Chen

    2014-03-01

    Full Text Available Advanced tissue engineering (TE technology based on additive manufacturing (AM can fabricate scaffolds with a three-dimensional (3D environment suitable for cartilage regeneration. Specifically, AM technology may allow the incorporation of complex architectural features. The present study involves the fabrication of 3D TE scaffolds by an indirect AM approach using silk fibroin (SF. From scanning electron microscopic observations, the presence of micro-pores and interconnected channels within the scaffold could be verified, resulting in a TE scaffold with both micro- and macro-structural features. The intrinsic properties, such as the chemical structure and thermal characteristics of SF, were preserved after the indirect AM manufacturing process. In vitro cell culture within the SF scaffold using porcine articular chondrocytes showed a steady increase in cell numbers up to Day 14. The specific production (per cell basis of the cartilage-specific extracellular matrix component (collagen Type II was enhanced with culture time up to 12 weeks, indicating the re-differentiation of chondrocytes within the scaffold. Subcutaneous implantation of the scaffold-chondrocyte constructs in nude mice also confirmed the formation of ectopic cartilage by histological examination and immunostaining.

  18. Sex-Specific Protection of Osteoarthritis by Deleting Cartilage Acid Protein 1.

    Directory of Open Access Journals (Sweden)

    Xianpeng Ge

    Full Text Available Cartilage acidic protein 1 (CRTAC1 was recently identified as an elevated protein in the synovial fluid of patients with osteoarthritis (OA by a proteomic analysis. This gene is also upregulated in both human and mouse OA by transcriptomic analysis. The objective of this study was to characterize the expression and function of CRTAC1 in OA. Here, we first confirm the increase of CRTAC1 in cartilage biopsies from OA patients undergoing joint replacement by real-time PCR and immunohistochemistry. Furthermore, we report that proinflammatory cytokines interleukin-1beta and tumor necrosis factor alpha upregulate CRTAC1 expression in primary human articular chondrocytes and synovial fibroblasts. Genetic deletion of Crtac1 in mice significantly inhibited cartilage degradation, osteophyte formation and gait abnormalities of post-traumatic OA in female, but not male, animals undergoing the destabilization of medial meniscus (DMM surgery. Taken together, CRTAC1 is upregulated in the osteoarthritic joint and directly induced in chondrocytes and synovial fibroblasts by pro-inflammatory cytokines. This molecule is necessary for the progression of OA in female mice after DMM surgery and thus represents a potential therapy for this prevalent disease, especially for women who demonstrate higher rates and more severe OA.

  19. Measurement of low permeabilities and of pinpoint hydraulic load variations as a function of depth in crystalline formations

    International Nuclear Information System (INIS)

    As part of the programme on management and storage of radioactive wastes, the PIEZOFOR system was improved in two directions, with a view to hydrogeological measurements in low permeability crystalline formations: - the special casing of the boreholes, on the one hand; - the measurement probe, on the other hand. In parallel, a specific software package for automatic interpretation of the measurements was put into operation

  20. Cartilage Protective and Chondrogenic Capacity of WIN-34B, a New Herbal Agent, in the Collagenase-Induced Osteoarthritis Rabbit Model and in Progenitor Cells from Subchondral Bone

    Directory of Open Access Journals (Sweden)

    Jeong-Eun Huh

    2013-01-01

    Full Text Available We sought to determine the cartilage repair capacity of WIN-34B in the collagenase-induced osteoarthritis rabbit model and in progenitor cells from subchondral bone. The cartilage protective effect of WIN-34B was measured by clinical and histological scores, cartilage area, and proteoglycan and collagen contents in the collagenase-induced osteoarthritis rabbit model. The efficacy of chondrogenic differentiation of WIN-34B was assessed by expression of CD105, CD73, type II collagen, and aggrecan in vivo and was analyzed by the surface markers of progenitor cells, the mRNA levels of chondrogenic marker genes, and the level of proteoglycan, GAG, and type II collagen in vitro. Oral administration of WIN-34B significantly increased cartilage area, and this was associated with the recovery of proteoglycan and collagen content. Moreover, WIN-34B at 200 mg/kg significantly increased the expression of CD105, CD73, type II collagen, and aggrecan compared to the vehicle group. WIN-34B markedly enhanced the chondrogenic differentiation of CD105 and type II collagen in the progenitor cells from subchondral bone. Also, we confirmed that treatment with WIN-34B strongly increased the number of SH-2(CD105 cells and expression type II collagen in subchondral progenitor cells. Moreover, WIN-34B significantly increased proteoglycan, as measured by alcian blue staining; the mRNA level of type II α1 collagen, cartilage link protein, and aggrecan; and the inhibition of cartilage matrix molecules, such as GAG and type II collagen, in IL-1β-treated progenitor cells. These findings suggest that WIN-34B could be a potential candidate for effective anti-osteoarthritic therapy with cartilage repair as well as cartilage protection via enhancement of chondrogenic differentiation in the collagenase-induced osteoarthritis rabbit model and progenitor cells from subchondral bone.

  1. An in situ hybridization study of Runx2, Osterix, and Sox9 in the anlagen of mouse mandibular condylar cartilage in the early stages of embryogenesis.

    Science.gov (United States)

    Shibata, Shunichi; Yokohama-Tamaki, Tamaki

    2008-09-01

    Mandibular condylar cartilage is the best-studied mammalian secondary cartilage, differing from primary cartilage in that it originates from alkaline phosphatase-positive progenitor cells. We previously demonstrated that three transcription factors related to bone and cartilage formation, namely Runx2, Osterix and Sox9, are simultaneously expressed in the anlage of mandibular condylar cartilage (condylar anlage) at embryonic day (E)14. In this study, expression of these transcription factors was investigated in the anlagen of mandibular bone (mandibular anlagen) from E11.0 to 14.0. Runx2 mRNA was first expressed in the mandibular anlage at E11.5. Osterix mRNA was first expressed at E12.0, and showed a different expression pattern from that of Runx2 from E12.5 to E14.0, confirming that Osterix acts downstream of Runx2. Sox9 mRNA was expressed in Meckel's cartilage and its anlagen throughout the experimental period, but not clearly in the mandibular anlagen until E13.0. At E13.5, the condylar anlage was morphologically identified at the posterior end of the mandibular anlage, and enhanced Sox9 mRNA expression was detected here. At this stage, Runx2 and Osterix mRNA were simultaneously detected in the condylar anlage. These results indicate that the Sox9 mRNA-expressing condylar anlage is derived from Runx2/Osterix mRNA-expressing mandibular anlage, and that upregulation of Sox9 in this region acts as a trigger for subsequent condylar cartilage formation.

  2. Electrical Resistivity Measurements in Sandstone During CH4 Hydrate Formation and CH4-CO2 Exchange

    Science.gov (United States)

    Birkedal, K.; Hauge, L.; Ersland, G.; Graue, A.

    2012-12-01

    The electrical properties of hydrate bearing sediments change with mineralogy, porosity, hydrate saturation, brine salinity, and mobility of the formation brine. Reliable calibration data is therefore essential for correct interpretation. Electrical resistivity measurements have been conducted on homogeneous Bentheim sand during CH4 hydrate formation. Various initial conditions (salinity and Sw) were used to determine the robustness of resistivity as a measure of hydrate saturation. Two setups with different electrode-arrangements were used; the first setup was a four electrode core holder without imaging capabilities, the second a two-electrode core holder used in combination with MRI to calibrate saturation data. The agreement between the two setups was good and there was little variation in phase angle. An initial resistivity decrease was observed at the initiation of hydrate growth for all experiments. This effect was more pronounced with lower initial salinities. Further increase in hydrate saturation resulted in reduced pore connectivity and increased tortuosity which resulted in increased resistivity (45-2487 kΩ). Only CH4 and water were used to form hydrate. The brine NaCl concentration of the remaining brine solution therefore increased during hydrate growth. Dynamic Rw and R0 values were incorporated into Archie's equations to account for changes in brine composition during hydrate formation. Resistivity was also measured during exchange between CH4-hydrate and CO2. There was an immediate resistivity and pressure response as CO2 was introduced to the system. This may be explained by higher water activity and CO2-hydrate growth at the trans-axial core face as CO2 is the preferred guest molecule at the experimental conditions. A spontaneous exchange therefore occurs, where the change in enthalpy accelerates the exchange. The resistivity showed a continuous decreasing trend after CO2 was introduced. This is explained by local in-equilibrium where

  3. A study on the ectopic cartilage formation of adipose-derived stem cells by adenovirus-mediated HIF-1α gene transfection%腺病毒介导HIF-1α修饰的脂肪源性干细胞异位成软骨的研究

    Institute of Scientific and Technical Information of China (English)

    潘玮敏

    2011-01-01

    目的 探讨重组腺病毒介导的低氧诱导因子-1α (HIF-1α)基因转染对脂肪源性干细胞(adipose-derived stem cells,ASCs)异位成软骨的作用.方法 构建能介导HIF-1α基因转染和表达的腺病毒载体(Ad-HIF-1α-GFP),转染体外培养的ASCs,RT-PCR检测其HIF-1α基因的表达,同时检测转染后细胞II型胶原的表达.随后将纤维蛋白胶分别与Ad-GFP-ASCs和Ad-HIF-1α-GFP-ASCs复合种植在裸鼠皮下,4周后行HE染色和甲苯胺蓝(Toluidine blue)染色进行观察.结果 荧光显微镜观察证实Ad-HIF-1α-GFP-ASCs的转染效率可达到80%;RT-PCR检测结果显示Ad-GFP-ASCs组微弱表达HIF-1α,Ad-HIF-1α-GFP-ASCs组HIF-1α基因则高表达,且Ad-HIF-1α-GFP-ASCs组II型胶原表达量明显高于Ad-GFP-ASCs组(P<0.05);形态学染色表明Ad-HIF-1α-GFP转染的ASCs主要为圆形,细胞伸展比率较低,但细胞数目较多,且细胞分泌较多的蛋白多糖.结论 腺病毒介导的HIF-1α可诱导ASCs向软骨细胞分化.%Objective To investigate the effect of ectopic cartilage formation of adipose-derived stem cells (ASCs) by adenovirus-mediated HIF-1α gene transfection.Methods Adenoviral vector was constructed with full length human HIF-1α gene and Ascs was transfected in vitro.The expressions of HIF-1α gene and collagen Ⅱ gene were detected by RT-PCR in transfected group.Then Fibrin glue and those composites mixed with Ad-GFP-ASCs and AdHIF-1α-GFP-ASCs respectively were transplanted into those naked mice.Those samples were acquired after 4 weeks and were tested by H&E and Toluidine blue staining.Results Confirmed by fluorescence microscope, the transfection efficiency of Ad-HIF-1α-GFP-ASCs was 80%.The expression of HIF-1α gene was positive in the Ad-HIF-1α-GFPASCs group and negative in the Ad-GFP-ASCs group according to the RT-PCR test results, and the relative value of the expression of collagen Ⅱ mRNA had significant difference between the two groups (P<0.05).Histology

  4. On the Incorporation of Metallicity Data into Measurements of Star Formation History from Resolved Stellar Populations

    Science.gov (United States)

    Dolphin, Andrew E.

    2016-07-01

    The combination of spectroscopic stellar metallicities and resolved star color–magnitude diagrams (CMDs) has the potential to constrain the entire star formation history (SFH) of a galaxy better than fitting CMDs alone (as is most common in SFH studies using resolved stellar populations). In this paper, two approaches to incorporating external metallicity information into CMD-fitting techniques are presented. Overall, the joint fitting of metallicity and CMD information can increase the precision of measured age–metallicity relationships (AMRs) and star formation rates by 10% over CMD fitting alone. However, systematics in stellar isochrones and mismatches between spectroscopic and photometric determinations of metallicity can reduce the accuracy of the recovered SFHs. I present a simple mitigation of these systematics that can reduce their amplitude to the level obtained from CMD fitting alone, while ensuring that the AMR is consistent with spectroscopic metallicities. As is the case in CMD-fitting analysis, improved stellar models and calibrations between spectroscopic and photometric metallicities are currently the primary impediment to gains in SFH precision from jointly fitting stellar metallicities and CMDs.

  5. BLAST: A FAR-INFRARED MEASUREMENT OF THE HISTORY OF STAR FORMATION

    International Nuclear Information System (INIS)

    We directly measure redshift evolution in the mean physical properties (far-infrared luminosity, temperature, and mass) of the galaxies that produce the cosmic infrared background (CIB), using measurements from the Balloon-borne Large Aperture Submillimeter Telescope (BLAST), and Spitzer which constrain the CIB emission peak. This sample is known to produce a surface brightness in the BLAST bands consistent with the full CIB, and photometric redshifts are identified for all of the objects. We find that most of the 70 μm background is generated at z ∼ 1. A significant growth is observed in the mean luminosity from ∼109-1012 Lsun, and in the mean temperature by 10 K, from redshifts 0 < z < 3. However, there is only weak positive evolution in the comoving dust mass in these galaxies across the same redshift range. We also measure the evolution of the far-infrared luminosity density, and the star formation rate history for these objects, finding good agreement with other infrared studies up to z ∼ 1, exceeding the contribution attributed to optically selected galaxies.

  6. Formation of a hybrid plasmonic waveguide mode probed by dispersion measurement

    Energy Technology Data Exchange (ETDEWEB)

    Saito, H. [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Quantum Nanoelectronics Research Center, Tokyo Institute of Technology, Oh-Okayama, Meguro-ku, Tokyo 152-8551 (Japan); Kurata, H., E-mail: kurata@eels.kuicr.kyoto-u.ac.jp [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2015-04-07

    Hybrid waveguides, i.e., dielectric waveguides combined with plasmonic waveguides, have great potential for concomitantly exhibiting subwavelength confinement and long range propagation, enabling a highly integrated photonic circuit. We report the characterization of hybrid waveguide modes excited in Si/SiO{sub 2}/Al films, by dispersion measurement using angle-resolved electron energy-loss spectroscopy. This experiment directly verifies the formation of the hybrid waveguide mode with a strongly localized electromagnetic field in a 6-nm-thick SiO{sub 2} layer. The results clearly describe the characteristic behavior of the hybrid waveguide mode, which depends on the effective index of the constituent dielectric waveguide and the surface plasmon-polariton modes.

  7. Measuring temperature of the ice surface during its formation by using infrared instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Karev, Anatolij R.; Farzaneh, Masoud; Kollar, Laszlo E. [NSERC/Hydro-Quebec/UQAC Industrial Chair on Atmospheric Icing of Power Network Equipment (CIGELE) and Canada Research Chair on Engineering of Power Network Atmospheric Icing (INGIVRE), Universite du Quebec a Chicoutimi, Chicoutimi, Que. (Canada)

    2007-02-15

    A non-destructive remote sensing technique was used to measure the surface temperature of a thin macroscopic water film flowing on a growing asymmetric ice accretion during its formation inside an icing research wind tunnel. Given the underlying thermodynamic conditions of this experimental series, the recorded surface temperature was always below the temperature of water fusion, T{sub m}=273.15K, even when water shedding from growing ice accretions was observed visually. The surface temperature of ice accretions, T{sub s}, ranged from -1{sup o}C, for angular positions near the stagnation line, down to a certain minimum above the ambient temperature, T{sub a}, for the greater angular positions, i.e. T{sub m}>T{sub s}>T{sub a}. (author)

  8. Premature Calcifications of Costal Cartilages: A New Perspective Premature Calcifications of Costal Cartilages: A New Perspective

    International Nuclear Information System (INIS)

    Calcifications of the costal cartilages occur, as a rule, not until the age of 30 years. The knowledge of the clinical significance of early and extensive calcifications is still incomplete. Materials and Methods. A search was made to find patients below the age of 30 years who showed distinct calcifications of their lower costal cartilages by viewing 360 random samples of intravenous pyelograms and abdominal plain films. The histories, and clinical and laboratory findings of these patients were analyzed. Results. Nineteen patients fulfilled the criteria of premature calcifications of costal cartilages (CCCs). The patients had in common that they were frequently referred to a hospital and were treated by several medical disciplines. Nevertheless many complaints of the patients remained unsolved. Premature CCCs were often associated with rare endocrine disorders, inborn errors of metabolism, and abnormal hematologic findings. Among the metabolic disorders there were 2 proven porphyrias and 7 patients with a suspected porphyria but with inconclusive laboratory findings. Conclusion. Premature CCCs are unlikely to be a normal variant in skeletal radiology. The findings in this small group of patients call for more intensive studies, especially in regard to the putative role of a porphyria

  9. Techniques for diced cartilage with deep temporalis fascia graft.

    Science.gov (United States)

    Calvert, Jay; Kwon, Edwin

    2015-02-01

    Diced cartilage with deep temporalis fascia (DC-F) graft has become a popular technique for reconstruction of the nasal dorsum. Cartilage can be obtained from the septum, ear, or costal cartilage when employing the DC-F technique. The complications seen with DC-F grafts tend to occur early in the surgeon's implementation of this technique. Management of the complications varies depending on the severity of the problem. This article gives an overview of both the technique and the complications commonly encountered.

  10. Prospective Clinical Trial for Septic Arthritis: Cartilage Degradation and Inflammation Are Associated with Upregulation of Cartilage Metabolites

    Directory of Open Access Journals (Sweden)

    Hagen Schmal

    2016-01-01

    Full Text Available Background. Intra-articular infections can rapidly lead to osteoarthritic degradation. The aim of this clinical biomarker analysis was to investigate the influence of inflammation on cartilage destruction and metabolism. Methods. Patients with acute joint infections were enrolled in a prospective clinical trial and the cytokine composition of effusions (n=76 was analyzed. Characteristics of epidemiology and disease severity were correlated with levels of cytokines with known roles in cartilage turnover and degradation. Results. Higher synovial IL-1β concentrations were associated with clinical parameters indicating a higher disease severity (p<0.03 excluding the incidence of sepsis. Additionally, intra-articular IL-1β levels correlated with inflammatory serum parameters as leucocyte counts (LC and C-reactive protein concentrations (p<0.05 but not with age or comorbidity. Both higher LC and synovial IL-1β levels were associated with increased intra-articular collagen type II cleavage products (C2C indicating cartilage degradation. Joints with preinfectious lesions had higher C2C levels. Intra-articular inflammation led to increased concentrations of typical cartilage metabolites as bFGF, BMP-2, and BMP-7. Infections with Staphylococcus species induced higher IL-1β expression but less cartilage destruction than other bacteria. Conclusion. Articular infections have bacteria-specific implications on cartilage metabolism. Collagen type II cleavage products reliably mark destruction, which is associated with upregulation of typical cartilage turnover cytokines. This trial is registered with DRKS00003536, MISSinG.

  11. Butterfly cartilage graft versus fat graft myringoplasty

    Directory of Open Access Journals (Sweden)

    Sonika Kanotra

    2016-01-01

    Full Text Available Aim: The aim of the study was to compare the graft take up rates of two minimally invasive techniques of butterfly cartilage graft (BCG and fat graft myringoplasty (FGM. Materials and Methods: Two groups of 30 patients each with small dry central perforations of the tympanic membrane (T.M. were randomly subjected to either of the two techniques of myringoplasty. Statistical Analysis Used: The results were compared using the Chi-square test. A value of <0.05 was taken as statistically significant. Results: The graft take up rate was 93.3% with BCG and 83.3% with fat graft. Conclusions: The BCG scores over FGM in small perforations of the T.M.

  12. Effects of anti-arthritic drugs on proteoglycan synthesis by equine cartilage.

    Science.gov (United States)

    Frean, S P; Cambridge, H; Lees, P

    2002-08-01

    The concentration-effect relationships of phenylbutazone, indomethacin, betamethasone, pentosan polysulphate (PPS) and polysulphated glycosaminoglycan (PSGAG), on proteoglycan synthesis by equine cultured chondrocytes grown in monolayers, and articular cartilage explants were measured. The effect of PSGAG on interleukin-1beta induced suppression of proteogycan synthesis was also investigated. Proteoglycan synthesis was measured by scintillation assay of radiolabelled sulphate (35SO4) incorporation. Polysulphated glycosaminoglycan and PPS stimulated proteoglycan synthesis in chondrocyte monolayers in a concentration-related manner with maximal effects being achieved at a concentration of 10 microg/mL. Polysulphated glycosaminoglycan reversed the concentration-related suppression of proteoglycan synthesis induced by interleukin-1beta. Neither PSGAG nor PPS exerted significant effects on radiolabel incorporation in cartilage explants. Betamethasone suppressed proteoglycan synthesis by both chondrocytes and explants at high concentrations (0.1-100 microg/mL), but the effect was not concentration-related. At low concentrations (0.001-0.05 microg/mL) betamethasone neither increased nor decreased proteoglycan synthesis. Phenylbutazone and indomethacin increased radiolabel incorporation in chondrocyte cultures but not in cartilage explants at low (0.1, 1 and 10 microg/mL), but not at high (20 and 100 microg/mL) concentrations. These findings may be relevant to the clinical use of these drugs in the treatment of equine disease. PMID:12213118

  13. A tetracycline expression system in combination with Sox9 for cartilage tissue engineering.

    Science.gov (United States)

    Yao, Yi; He, Yu; Guan, Qian; Wu, Qiong

    2014-02-01

    Cartilage tissue engineering using controllable transcriptional therapy together with synthetic biopolymer scaffolds shows higher potential for overcoming chondrocyte degradation and constructing artificial cartilages both in vivo and in vitro. Here, the potential regulating tetracycline expression (Tet-on) system was used to express Sox9 both in vivo and in vitro. Chondrocyte degradation was measured in vitro and overcome by Soxf9 expression. Experiments confirmed the feasibility of the combined use of Sox9 and Tet-on system in cartilage tissue engineering. Engineered poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) scaffolds were seeded with recombinant chondrocytes which were transfected with Tet-induced Sox9 expression; the scaffolds were implanted under the skin of 8-week-old rats. The experimental group was injected with Dox in the abdomen, while the control group was injected with normal saline. After 4 or 8 days of implantation in vivo, the newly formed pieces of articular chondrocytes were taken out and measured. Dox injection in vivo showed positive effect on recombinant chondrocytes, in which Sox9 expression was up-regulated by an inducible system with specific matrix proteins. The results demonstrate this controllable transcriptional therapy is a potential approach for tissue engineering. PMID:24321708

  14. In vitro and In vivo Evaluation of the Developed PLGA/HAp/Zein Scaffolds for Bone-Cartilage Interface Regeneration

    Institute of Scientific and Technical Information of China (English)

    LIN Yong Xin; DING Zhi Yong; ZHOU Xiao Bin; LI Si Tao; XIE De Ming; LI Zhi Zhong; SUN Guo Dong

    2015-01-01

    Objective To investigate the effect of electronspun PLGA/HAp/Zein scaffolds on the repair of cartilage defects. Methods The PLGA/HAp/Zein composite scaffolds were fabricated by electrospinning method. The physiochemical properties and biocompatibility of the scaffolds were separately characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), and fourier transform infrared spectroscopy (FTIR), human umbilical cord mesenchymal stem cells (hUC-MSCs) culture and animal experiments. Results The prepared PLGA/HAp/Zein scaffolds showed fibrous structure with homogenous distribution. hUC-MSCs could attach to and grow well on PLGA/HAp/Zein scaffolds, and there was no significant difference between cell proliferation on scaffolds and that without scaffolds (P>0.05). The PLGA/HAp/Zein scaffolds possessed excellent ability to promote in vivo cartilage formation. Moreover, there was a large amount of immature chondrocytes and matrix with cartilage lacuna on PLGA/HAp/Zein scaffolds. Conclusion The data suggest that the PLGA/HAp/Zein scaffolds possess good biocompatibility, which are anticipated to be potentially applied in cartilage tissue engineering and reconstruction.

  15. 7 Tesla quantitative hip MRI: T1, T2 and T2* mapping of hip cartilage in healthy volunteers

    Energy Technology Data Exchange (ETDEWEB)

    Lazik, Andrea; Theysohn, Jens M.; Geis, Christina [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Johst, Soeren; Kraff, Oliver [University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); Ladd, Mark E. [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); German Cancer Research Center (DKFZ), Medical Physics in Radiology, Heidelberg (Germany); Quick, Harald H. [University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); University Hospital Essen, High Field and Hybrid MR Imaging, Essen (Germany)

    2016-05-15

    To evaluate the technical feasibility and applicability of quantitative MR techniques (delayed gadolinium-enhanced MRI of cartilage (dGEMRIC), T2 mapping, T2* mapping) at 7 T MRI for assessing hip cartilage. Hips of 11 healthy volunteers were examined at 7 T MRI with an 8-channel radiofrequency transmit/receive body coil using multi-echo sequences for T2 and T2* mapping and a dual flip angle gradient-echo sequence before (T1{sub 0}) and after intravenous contrast agent administration (T1{sub Gd}; 0.2 mmol/kg Gd-DTPA{sup 2-} followed by 0.5 h of walking and 0.5 h of rest) for dGEMRIC. Relaxation times of cartilage were measured manually in 10 regions of interest. Pearson's correlations between R1{sub delta} = 1/T1{sub Gd} - 1/T1{sub 0} and T1{sub Gd} and between T2 and T2* were calculated. Image quality and the delineation of acetabular and femoral cartilage in the relaxation time maps were evaluated using discrete rating scales. High correlations were found between R1{sub delta} and T1{sub Gd} and between T2 and T2* relaxation times (all p < 0.01). All techniques delivered diagnostic image quality, with best delineation of femoral and acetabular cartilage in the T2* maps (mean 3.2 out of a maximum of 4 points). T1, T2 and T2* mapping of hip cartilage with diagnostic image quality is feasible at 7 T. To perform dGEMRIC at 7 T, pre-contrast T1 mapping can be omitted. (orig.)

  16. Prevention of Cartilage Degeneration and Restoration of Chondroprotection by Lubricin Tribosupplementation in the Rat Following ACL Transection

    Science.gov (United States)

    Jay, Gregory D.; Fleming, Braden C.; Watkins, Bryn A.; McHugh, Karen A.; Anderson, Scott C.; Zhang, Ling X.; Teeple, Erin; Waller, Kimberly A.; Elsaid, Khaled A.

    2010-01-01

    Objective To investigate whether cartilage degeneration is prevented or minimized in an anterior cruciate ligament (ACL) injury rat model following intra-articular injections of lubricin derived from human synoviocytes in culture (HSL), recombinant protein (rhPRG4), or from human synovial fluids (HSFL). Methods Unilateral ACL transection (ACLT) was performed in Lewis rats (n=45). Intra-articular injections (50μl/injection) of PBS (n=9), HSL (n=9; 200μg/ml), rhPRG4 (n=9; 200μg/ml) and HSFL (n=9; 200μg/ml) started on day 7 post-injury and continued twice weekly. Animals were harvested on day 32 post-injury. Histological analysis was performed using Safranin O/Fast green stain and blinded investigators graded articular cartilage degeneration using OARSI modified Mankin criteria. Histological specimens were immunoprobed for lubricin and sulphated glycosaminoglycans. 24 hour urine collection was performed on days 17 and 29 post-injury and urinary CTXII (uCTXII) levels were measured. Results Treatment with HSL resulted in significantly (p<0.05) lower OARSI scores for cartilage degeneration compared to no treatment or PBS treatment. Increased immunostaining for lubricin in the superficial zone chondrocytes and on the surface of cartilage was observed in lubricins-treated but not untreated or PBS-treated joints. On day 17, uCTXII levels of HSL and HSFL-treated animals were significantly lower than untreated (p=0.005; p=0.002) and PBS-treated (p=0.002; p<0.001) animals, respectively. Conclusion Across all types of lubricin evaluated in this study, a reduction in cartilage damage following ACLT was evident, combined with a reduction in collagen type II degradation. Intraarticular lubricin injection following an ACL injury may be beneficial in retarding cartilage degeneration and development of post-traumatic OA. PMID:20506144

  17. Technical Note: How accurate can stalagmite formation temperatures be determined using vapour bubble radius measurements in fluid inclusions?

    DEFF Research Database (Denmark)

    Spadin, F.; Marti, Dominik; Hidalgo-Staub, R.;

    2015-01-01

    Stalagmites are natural archives containing detailed information on continental climate variability of the past. Microthermometric measurements of fluid inclusion homogenisation temperatures allow determination of stalagmite formation temperatures by measuring the radius of stable laser-induced v......Stalagmites are natural archives containing detailed information on continental climate variability of the past. Microthermometric measurements of fluid inclusion homogenisation temperatures allow determination of stalagmite formation temperatures by measuring the radius of stable laser...... the uncertainty in determining the formation temperature is provided. We demonstrate that the nominal homogenisation temperature of a single inclusion can be determined with an accuracy of ±0.25 ◦C, if the volume of the inclusion is larger than 105 µm3 . With this method, we could measure in a proof-of-principle...

  18. The development of the collagen fibre network in tissue-engineered cartilage constructs in vivo. Engineered cartilage reorganises fibre network

    Directory of Open Access Journals (Sweden)

    H Paetzold

    2012-04-01

    Full Text Available For long term durability of tissue-engineered cartilage implanted in vivo, the development of the collagen fibre network orientation is essential as well as the distribution of collagen, since expanded chondrocytes are known to synthesise collagen type I. Typically, these properties differ strongly between native and tissue-engineered cartilage. Nonetheless, the clinical results of a pilot study with implanted tissue-engineered cartilage in pigs were surprisingly good. The purpose of this study was therefore to analyse if the structure and composition of the artificial cartilage tissue changes in the first 52 weeks after implantation. Thus, collagen network orientation and collagen type distribution in tissue-engineered cartilage-carrier-constructs implanted in the knee joints of Göttinger minipigs for 2, 26 or 52 weeks have been further investigated by processing digitised microscopy images of histological sections. The comparison to native cartilage demonstrated that fibre orientation over the cartilage depth has a clear tendency towards native cartilage with increasing time of implantation. After 2 weeks, the collagen fibres of the superficial zone were oriented parallel to the articular surface with little anisotropy present in the middle and deep zones. Overall, fibre orientation and collagen distribution within the implants were less homogenous than in native cartilage tissue. Despite a relatively low number of specimens, the consistent observation of a continuous approximation to native tissue is very promising and suggests that it may not be necessary to engineer the perfect tissue for implantation but rather to provide an intermediate solution to help the body to heal itself.

  19. Combining metal and nonmetal isotopic measurements in barite to identify mode of formation

    Science.gov (United States)

    Griffith, E. M.; Paytan, A.; Eisenhauer, A.; Scher, H. D.; Wortmann, U.

    2014-12-01

    Barite (BaSO4) is a highly stable and widely-distributed mineral found in magmatic, metamorphic, and sedimentary rocks (of all ages), as well as in soils, aerosol dust, and extraterrestrial material. Today, barite can form in a variety of settings in the oceans (hydrothermal, cold seeps, water column, sediments) and on the continents - where supersaturation and precipitation of barite typically occurs from the mixing of fluids - one containing Ba and another containing sulfate. Sulfur (δ34S) and oxygen (δ18O) isotopes together with 87Sr/86Sr and stable Sr-isotopic signatures (δ88/86Sr) of modern authigenic continental barite are compared to modern pelagic marine barite and marine hydrothermal and cold seep barite to investigate the potential for their combined use to indicate mode of barite formation. The 87Sr/86Sr in barite cleary identifies the source of fluid for any particular type of barite (as previously noted, see Paytan et al., 2002). The highest (most radiogenic) 87Sr/86Sr values are measured in continental barite samples. There is no unique δ88/86Sr signature for any particular type of barite, but coretop marine (pelagic) barite has a consistent value measured from samples collected in different ocean basins. The highest and lowest δ88/86Sr values were measured in continental barite samples. The combination of isotopic systems result in unique δ88/86Sr and δ18O relationships and distinct δ88/86Sr and δ34S relationships for different types of barites investigated. Data suggest that the combined use of these metal and nonmetal isotopic measurements in barite could be useful as a new geochemical proxy to identify mode of barite mineralization for use in earth science applications including understanding ancient barite deposits.

  20. 3D MRI volume sizing of knee meniscus cartilage.

    Science.gov (United States)

    Stone, K R; Stoller, D W; Irving, S G; Elmquist, C; Gildengorin, G

    1994-12-01

    Meniscal replacement by allograft and meniscal regeneration through collagen meniscal scaffolds have been recently reported. To evaluate the effectiveness of a replaced or regrown meniscal cartilage, a method for measuring the size and function of the regenerated tissue in vivo is required. To solve this problem, we developed and evaluated a magnetic resonance imaging (MRI) technique to measure the volume of meniscal tissues. Twenty-one intact fresh cadaver knees were evaluated and scanned with MRI for meniscal volume sizing. The sizing sequence was repeated six times for each of 21 lateral and 12 medial menisci. The menisci were then excised and measured by water volume displacement. Each volume displacement measurement was repeated six times. The MRI technique employed to measure the volume of the menisci was shown to correspond to that of the standard measure of volume and was just as precise. However, the MRI technique consistently underestimated the actual volume. The average of the coefficient of variation for lateral volumes was 0.04 and 0.05 for the water and the MRI measurements, respectively. For medial measurements it was 0.04 and 0.06. The correlation for the lateral menisci was r = 0.45 (p = 0.04) and for the medial menisci it was r = 0.57 (p = 0.05). We conclude that 3D MRI is precise and repeatable but not accurate when used to measure meniscal volume in vivo and therefore may only be useful for evaluating changes in meniscal allografts and meniscal regeneration templates over time.

  1. Contribution of regional 3D meniscus and cartilage morphometry by MRI to joint space width in fixed flexion knee radiography—A between-knee comparison in subjects with unilateral joint space narrowing

    International Nuclear Information System (INIS)

    Background: Radiographic joint space width (JSW) is considered the reference standard for demonstrating structural therapeutic benefits in knee osteoarthritis. Our objective was to determine the proportion by which 3D (regional) meniscus and cartilage measures explain between-knee differences of JSW in the fixed flexion radiographs. Methods: Segmentation of the medial meniscus and tibial and femoral cartilage was performed in double echo steady state (DESS) images. Quantitative measures of meniscus size and position, femorotibial cartilage thickness, and radiographic JSW (minimum, and fixed locations) were compared between both knees of 60 participants of the Osteoarthritis Initiative, with strictly unilateral medial joint space narrowing (JSN). Statistical analyses (between-knee, within-person comparison) were performed using regression analysis. Results: A strong relationship with side-differences in minimum and a central fixed location JSW was observed for percent tibial plateau coverage by the meniscus (r = .59 and .47; p < .01) and central femoral cartilage thickness (r = .69 and .75; p < .01); other meniscus and cartilage measures displayed lower coefficients. The correlation of central femoral cartilage thickness with JSW (but not that of meniscus measures) was greater (r = .78 and .85; p < .01) when excluding knees with non-optimal alignment between the tibia and X-ray beam. Conclusion: 3D measures of meniscus and cartilage provide significant, independent information in explaining side-differences in radiographic JSW in fixed flexion radiographs. Tibial coverage by the meniscus and central femoral cartilage explained two thirds of the variability in minimum and fixed location JSW. JSW provides a better representation of (central) femorotibial cartilage thickness, when optimal positioning of the fixed flexion radiographs is achieved

  2. Contribution of regional 3D meniscus and cartilage morphometry by MRI to joint space width in fixed flexion knee radiography—A between-knee comparison in subjects with unilateral joint space narrowing

    Energy Technology Data Exchange (ETDEWEB)

    Bloecker, K., E-mail: katja.bloecker@pmu.ac.at [Institute of Anatomy and Musculoskeletal Research, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg (Austria); Department of Traumatology and Sports Medicine, Paracelsus Medical University, Müllner Hauptstrasse 48, 5020 Salzburg (Austria); Wirth, W., E-mail: wolfgang.wirth@pmu.ac.at [Institute of Anatomy and Musculoskeletal Research, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg (Austria); Chondrometrics GmbH, Ulrichshöglerstrasse 23, 83404 Ainring (Germany); Hunter, D.J., E-mail: david.hunter@sydney.edu.au [Royal North Shore Hospital and Kolling Institute, University of Sydney, Pacific Highway, St Leonards, Sydney, NSW 2065 (Australia); Duryea, J., E-mail: jduryea@bwh.harvard.edu [Brigham and Women' s Hospital, Harvard Medical School, 75 Francis Street, Boston, MA (United States); Guermazi, A., E-mail: Ali.Guermazi@bmc.org [Boston University School of Medicine, Department of Radiology, 820 Harrison Avenue, FGH Building 3rd Floor, Boston, MA (United States); Boston Imaging Core Lab (BICL), 601 Albany Street, Boston, MA (United States); Kwoh, C.K., E-mail: kwoh@pitt.edu [Division of Rheumatology and Clinical Immunology, University of Arizona, Tucson, AZ (United States); Division of Rheumatology and Clinical Immunology, University of Pittsburgh and VA, Pittsburgh Healthcare System, 3500 Terrace Street, Biomedical Science Tower South 702, Pittsburgh, PA 15261 (United States); Resch, H., E-mail: Herbert.resch@salk.at [Department of Traumatology and Sports Medicine, Paracelsus Medical University, Müllner Hauptstrasse 48, 5020 Salzburg (Austria); Eckstein, F. [Institute of Anatomy and Musculoskeletal Research, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg (Austria); Chondrometrics GmbH, Ulrichshöglerstrasse 23, 83404 Ainring (Germany)

    2013-12-01

    Background: Radiographic joint space width (JSW) is considered the reference standard for demonstrating structural therapeutic benefits in knee osteoarthritis. Our objective was to determine the proportion by which 3D (regional) meniscus and cartilage measures explain between-knee differences of JSW in the fixed flexion radiographs. Methods: Segmentation of the medial meniscus and tibial and femoral cartilage was performed in double echo steady state (DESS) images. Quantitative measures of meniscus size and position, femorotibial cartilage thickness, and radiographic JSW (minimum, and fixed locations) were compared between both knees of 60 participants of the Osteoarthritis Initiative, with strictly unilateral medial joint space narrowing (JSN). Statistical analyses (between-knee, within-person comparison) were performed using regression analysis. Results: A strong relationship with side-differences in minimum and a central fixed location JSW was observed for percent tibial plateau coverage by the meniscus (r = .59 and .47; p < .01) and central femoral cartilage thickness (r = .69 and .75; p < .01); other meniscus and cartilage measures displayed lower coefficients. The correlation of central femoral cartilage thickness with JSW (but not that of meniscus measures) was greater (r = .78 and .85; p < .01) when excluding knees with non-optimal alignment between the tibia and X-ray beam. Conclusion: 3D measures of meniscus and cartilage provide significant, independent information in explaining side-differences in radiographic JSW in fixed flexion radiographs. Tibial coverage by the meniscus and central femoral cartilage explained two thirds of the variability in minimum and fixed location JSW. JSW provides a better representation of (central) femorotibial cartilage thickness, when optimal positioning of the fixed flexion radiographs is achieved.

  3. Measurement of Throughput Variation Across A Large Format Volume-Phase Holographic Grating

    CERN Document Server

    Tamura, N; Sharples, R M; Robertson, D J; Allington-Smith, J R; Tamura, Naoyuki; Murray, Graham J.; Sharples, Ray M.; Robertson, David J.

    2005-01-01

    In this paper, we report measurements of diffraction efficiency and angular dispersion for a large format (~ 25 cm diameter) Volume-Phase Holographic (VPH) grating optimized for near-infrared wavelengths (0.9 -- 1.8 micron). The aim of this experiment is to see whether optical characteristics vary significantly across the grating. We sampled three positions in the grating aperture with a separation of 5 cm between each. A 2 cm diameter beam is used to illuminate the grating. At each position, throughput and diffraction angle were measured at several wavelengths. It is found that whilst the relationship between diffraction angle and wavelength is nearly the same at the three positions, the throughputs vary by up to ~ 10\\% from position to position. We explore the origin of the throughput variation by comparing the data with predictions from coupled-wave analysis. We find that it can be explained by a combination of small variations over the grating aperture in gelatin depth and/or refractive index modulation a...

  4. Cartilage oligomeric matrix protein in patients with juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Bjørnhart, Birgitte; Juul, Anders; Nielsen, Susan;

    2009-01-01

    Cartilage oligomeric matrix protein (COMP) has been identified as a prognostic marker of progressive joint destruction in rheumatoid arthritis. In this population based study we evaluated associations between plasma concentrations of COMP, disease activity, and growth velocity in patients with...

  5. Endobronchial Cartilage Rupture: A Rare Cause of Lobar Collapse

    Science.gov (United States)

    Siddiqui, Nauman; Javaid, Toseef

    2016-01-01

    Endobronchial cartilage rupture is a rare clinical condition, which can present in patients with severe emphysema with sudden onset shortness of breath. We present a case of a 62-year-old male who presented to our emergency department with sudden onset shortness of breath. Chest X-ray showed lung hyperinflation and a right lung field vague small density. Chest Computed Tomography confirmed the presence of right middle lobe collapse. Bronchoscopy revealed partial right middle lobe atelectasis and an endobronchial cartilage rupture. Endobronchial cartilage rupture is a rare condition that can present as sudden onset shortness of breath due to lobar collapse in patients with emphysema and can be triggered by cough. Bronchoscopic findings include finding a collapsed lung lobe and a visible ruptured endobronchial cartilage. A high index of suspicion, chest imaging, and early bronchoscopy can aid in the diagnosis and help prevent complications. PMID:27525149

  6. Endobronchial Cartilage Rupture: A Rare Cause of Lobar Collapse.

    Science.gov (United States)

    Dasa, Osama; Siddiqui, Nauman; Ruzieh, Mohammed; Javaid, Toseef

    2016-01-01

    Endobronchial cartilage rupture is a rare clinical condition, which can present in patients with severe emphysema with sudden onset shortness of breath. We present a case of a 62-year-old male who presented to our emergency department with sudden onset shortness of breath. Chest X-ray showed lung hyperinflation and a right lung field vague small density. Chest Computed Tomography confirmed the presence of right middle lobe collapse. Bronchoscopy revealed partial right middle lobe atelectasis and an endobronchial cartilage rupture. Endobronchial cartilage rupture is a rare condition that can present as sudden onset shortness of breath due to lobar collapse in patients with emphysema and can be triggered by cough. Bronchoscopic findings include finding a collapsed lung lobe and a visible ruptured endobronchial cartilage. A high index of suspicion, chest imaging, and early bronchoscopy can aid in the diagnosis and help prevent complications. PMID:27525149

  7. Cartilage (Bovine and Shark) (PDQ®)—Health Professional Version

    Science.gov (United States)

    Expert-reviewed information summary about the use of bovine and shark cartilage as a treatment for people with cancer. Note: The information in this summary is no longer being updated and is provided for reference purposes only.

  8. Namaste (counterbalancing technique: Overcoming warping in costal cartilage

    Directory of Open Access Journals (Sweden)

    Kapil S Agrawal

    2015-01-01

    Full Text Available Background: Indian noses are broader and lack projection as compared to other populations, hence very often need augmentation, that too by large volume. Costal cartilage remains the material of choice in large volume augmentations and repair of complex primary and secondary nasal deformities. One major disadvantage of costal cartilage grafts (CCG which offsets all other advantages is the tendency to warp and become distorted over a period of time. We propose a simple technique to overcome this menace of warping. Materials and Methods: We present the data of 51 patients of rhinoplasty done using CCG with counterbalancing technique over a period of 4 years. Results: No evidence of warping was found in any patient up to a maximum follow-up period of 4 years. Conclusion: Counterbalancing is a useful technique to overcome the problem of warping. It gives liberty to utilize even unbalanced cartilage safely to provide desired shape and use the cartilage without any wastage.

  9. Cartilage reshaping: an overview of the state of the art

    Science.gov (United States)

    Karamzadeh, Amir M.; Sobol, Emil N.; Rasouli, Alexandre; Nelson, J. Stuart; Milner, Thomas E.; Wong, Brian J.

    2001-05-01

    The laser irradiation of cartilage results in a plastic deformation of the tissue allowing for the creation of new stable shapes. During photothermal stimulation, mechanically deformed cartilage undergoes a temperature dependent phase transition, which results in accelerated stress relaxation of the tissue matrix. Cartilage specimens thus reshaped can be used to recreate the underlying framework of structures in the head and neck. Optimization of this process has required an understanding of the biophysical processes accompanying reshaping and also determination of the laser dosimetry parameters, which maintain graft viability. Extensive in vitro, ex-vivo, and in vivo animal investigations, as well as human trials, have been conducted. This technology is now in use to correct septal deviations in an office-based setting. While the emphasis of clinical investigation has focused on septoplasty procedures, laser mediated cartilage reshaping may have application in surgical procedures involving the trachea, laryngeal framework, external ear, and nasal tip. Future directions for research and device design are discussed.

  10. Tailored PVA/ECM Scaffolds for Cartilage Regeneration

    Directory of Open Access Journals (Sweden)

    Elena Stocco

    2014-01-01

    Full Text Available Articular cartilage lesions are a particular challenge for regenerative medicine due to cartilage low self-ability repair in case of damage. Hence, a significant goal of musculoskeletal tissue engineering is the development of suitable structures in virtue of their matrix composition and biomechanical properties. The objective of our study was to design in vitro a supporting structure for autologous chondrocyte growth. We realized a biohybrid composite scaffold combining a novel and nonspecific extracellular matrix (ECM, which is decellularized Wharton’s jelly ECM, with the biomechanical properties of the synthetic hydrogel polyvinyl alcohol (PVA. Wharton’s jelly ECM was tested for its ability in promoting scaffold colonization by chondrocytes and compared with polyvinyl alcohol itself and the more specific decellularized cartilage matrix. Our preliminary evidences highlighted the chance of using Wharton’s jelly ECM in combination with PVA hydrogels as an innovative and easily available scaffold for cartilage restoration.

  11. Starch-modified magnetite nanoparticles for impregnation into cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Soshnikova, Yulia M., E-mail: yuliasoshnikova@gmail.com [Russian Academy of Sciences, Institute on Laser and Information Technologies (Russian Federation); Roman, Svetlana G.; Chebotareva, Natalia A. [A.N. Bach Institute of Biochemistry (Russian Federation); Baum, Olga I. [Russian Academy of Sciences, Institute on Laser and Information Technologies (Russian Federation); Obrezkova, Mariya V. [Lomonosov Moscow State University, Department of Chemistry (Russian Federation); Gillis, Richard B.; Harding, Stephen E. [University of Nottingham, National Centre for Macromolecular Hydrodynamics (United Kingdom); Sobol, Emil N. [Russian Academy of Sciences, Institute on Laser and Information Technologies (Russian Federation); Lunin, Valeriy V. [Lomonosov Moscow State University, Department of Chemistry (Russian Federation)

    2013-11-15

    The paper presents preparation and characterization of starch-modified Fe{sub 3}O{sub 4} nanoparticles (NPs) in aqueous dispersion after impregnation into healthy and damaged types of cartilage. We show that starch-modified dispersion has a narrower size distribution than a non‐stabilized one. The average hydrodynamic radius of magnetite NPs in a dispersion used for impregnation into cartilage is (48 ± 1) nm with the width of the distribution from 5 to 200 nm. We investigate stability of aqueous magnetite NPs dispersions during storage and with increase in temperature (up to 70 °C). We find that polydisperse magnetite NPs can penetrate into cartilage and the size and concentration of impregnated particles depend on the organization of the tissue structure. The results confirm the possibility of application of magnetite NPs in diagnostics and laser treatment of degenerative cartilage deceases.

  12. Post-traumatic glenohumeral cartilage lesions: a systematic review

    Directory of Open Access Journals (Sweden)

    Stussi Edgar

    2008-07-01

    Full Text Available Abstract Background Any cartilage damage to the glenohumeral joint should be avoided, as these damages may result in osteoarthritis of the shoulder. To understand the pathomechanism leading to shoulder cartilage damage, we conducted a systematic review on the subject of articular cartilage lesions caused by traumas where non impression fracture of the subchondral bone is present. Methods PubMed (MEDLINE, ScienceDirect (EMBASE, BIOBASE, BIOSIS Previews and the COCHRANE database of systematic reviews were systematically scanned using a defined search strategy to identify relevant articles in this field of research. First selection was done based on abstracts according to specific criteria, where the methodological quality in selected full text articles was assessed by two reviewers. Agreement between raters was investigated using percentage agreement and Cohen's Kappa statistic. The traumatic events were divided into two categories: 1 acute trauma which refers to any single impact situation which directly damages the articular cartilage, and 2 chronic trauma which means cartilage lesions due to overuse or disuse of the shoulder joint. Results The agreement on data quality between the two reviewers was 93% with a Kappa value of 0.79 indicating an agreement considered to be 'substantial'. It was found that acute trauma on the shoulder causes humeral articular cartilage to disrupt from the underlying bone. The pathomechanism is said to be due to compression or shearing, which can be caused by a sudden subluxation or dislocation. However, such impact lesions are rarely reported. In the case of chronic trauma glenohumeral cartilage degeneration is a result of overuse and is associated to other shoulder joint pathologies. In these latter cases it is the rotator cuff which is injured first. This can result in instability and consequent impingement which may progress to glenohumeral cartilage damage. Conclusion The great majority of glenohumeral cartilage

  13. Tissue Engineering Cartilage with a Composite Electrospun and Hydrogel Scaffold

    OpenAIRE

    Wright, Lee David

    2011-01-01

    Osteoarthritis is the most prevalent musculoskeletal disease in humans, severely reducing the standard of living of millions of people. Osteoarthritis is characterized by degeneration and loss of articular cartilage which leads to pain, and loss of joint motility and function. Individuals suffering from severe osteoarthritis are commonly treated with full knee replacements. The procedure does eliminate the problem of degrading cartilage tissue; however, it does not fully restore function a...

  14. Automatic ICRS scoring of cartilage lesions using arthroscopic OCT images

    OpenAIRE

    te Moller, Nikae; Pitkanen, M; Liukkonen, J.; Puhakka, P H; Brommer, Harold; J.S. Jurvelin; van Weeren, René; Toyras, J.

    2014-01-01

    Articular cartilage injury is a common cause of chronic disability in both humans and animals. Current treatment strategies offer several possibilities and in order to select the optimal repair procedure, accurate determination of size and severity of a lesion is important [1,2]. Recently, an equine ex vivo study showed that arthroscopic optical coherence tomography (OCT) provides high resolution optical images of the cartilage layer [3]. Furthermore, in that study morphological characteristi...

  15. Integration of Stem Cell to Chondrocyte-Derived Cartilage Matrix in Healthy and Osteoarthritic States in the Presence of Hydroxyapatite Nanoparticles.

    Science.gov (United States)

    Dua, Rupak; Comella, Kristin; Butler, Ryan; Castellanos, Glenda; Brazille, Bryn; Claude, Andrew; Agarwal, Arvind; Liao, Jun; Ramaswamy, Sharan

    2016-01-01

    We investigated the effectiveness of integrating tissue engineered cartilage derived from human bone marrow derived stem cells (HBMSCs) to healthy as well as osteoarthritic cartilage mimics using hydroxyapatite (HA) nanoparticles immersed within a hydrogel substrate. Healthy and diseased engineered cartilage from human chondrocytes (cultured in agar gels) were integrated with human bone marrow stem cell (HBMSC)-derived cartilaginous engineered matrix with and without HA, and evaluated after 28 days of growth. HBMSCs were seeded within photopolymerizable poly (ethylene glycol) diacrylate (PEGDA) hydrogels. In addition, we also conducted a preliminary in vivo evaluation of cartilage repair in rabbit knee chondral defects treated with subchondral bone microfracture and cell-free PEGDA with and without HA. Under in vitro conditions, the interfacial shear strength between tissue engineered cartilage derived from HBMSCs and osteoarthritic chondrocytes was significantly higher (p < 0.05) when HA nanoparticles were incorporated within the HBMSC culture system. Histological evidence confirmed a distinct spatial transition zone, rich in calcium phosphate deposits. Assessment of explanted rabbit knees by histology demonstrated that cellularity within the repair tissues that had filled the defects were of significantly higher number (p < 0.05) when HA was used. HA nanoparticles play an important role in treating chondral defects when osteoarthritis is a co-morbidity. We speculate that the calcified layer formation at the interface in the osteoarthritic environment in the presence of HA is likely to have attributed to higher interfacial strength found in vitro. From an in vivo standpoint, the presence of HA promoted cellularity in the tissues that subsequently filled the chondral defects. This higher presence of cells can be considered important in the context of accelerating long-term cartilage remodeling. We conclude that HA nanoparticles play an important role in engineered

  16. Integration of Stem Cell to Chondrocyte-Derived Cartilage Matrix in Healthy and Osteoarthritic States in the Presence of Hydroxyapatite Nanoparticles.

    Directory of Open Access Journals (Sweden)

    Rupak Dua

    Full Text Available We investigated the effectiveness of integrating tissue engineered cartilage derived from human bone marrow derived stem cells (HBMSCs to healthy as well as osteoarthritic cartilage mimics using hydroxyapatite (HA nanoparticles immersed within a hydrogel substrate. Healthy and diseased engineered cartilage from human chondrocytes (cultured in agar gels were integrated with human bone marrow stem cell (HBMSC-derived cartilaginous engineered matrix with and without HA, and evaluated after 28 days of growth. HBMSCs were seeded within photopolymerizable poly (ethylene glycol diacrylate (PEGDA hydrogels. In addition, we also conducted a preliminary in vivo evaluation of cartilage repair in rabbit knee chondral defects treated with subchondral bone microfracture and cell-free PEGDA with and without HA. Under in vitro conditions, the interfacial shear strength between tissue engineered cartilage derived from HBMSCs and osteoarthritic chondrocytes was significantly higher (p < 0.05 when HA nanoparticles were incorporated within the HBMSC culture system. Histological evidence confirmed a distinct spatial transition zone, rich in calcium phosphate deposits. Assessment of explanted rabbit knees by histology demonstrated that cellularity within the repair tissues that had filled the defects were of significantly higher number (p < 0.05 when HA was used. HA nanoparticles play an important role in treating chondral defects when osteoarthritis is a co-morbidity. We speculate that the calcified layer formation at the interface in the osteoarthritic environment in the presence of HA is likely to have attributed to higher interfacial strength found in vitro. From an in vivo standpoint, the presence of HA promoted cellularity in the tissues that subsequently filled the chondral defects. This higher presence of cells can be considered important in the context of accelerating long-term cartilage remodeling. We conclude that HA nanoparticles play an important role in

  17. Sequential change in T2* values of cartilage, meniscus, and subchondral bone marrow in a rat model of knee osteoarthritis.

    Directory of Open Access Journals (Sweden)

    Ping-Huei Tsai

    Full Text Available BACKGROUND: There is an emerging interest in using magnetic resonance imaging (MRI T2* measurement for the evaluation of degenerative cartilage in osteoarthritis (OA. However, relatively few studies have addressed OA-related changes in adjacent knee structures. This study used MRI T2* measurement to investigate sequential changes in knee cartilage, meniscus, and subchondral bone marrow in a rat OA model induced by anterior cruciate ligament transection (ACLX. MATERIALS AND METHODS: Eighteen male Sprague Dawley rats were randomly separated into three groups (n = 6 each group. Group 1 was the normal control group. Groups 2 and 3 received ACLX and sham-ACLX, respectively, of the right knee. T2* values were measured in the knee cartilage, the meniscus, and femoral subchondral bone marrow of all rats at 0, 4, 13, and 18 weeks after surgery. RESULTS: Cartilage T2* values were significantly higher at 4, 13, and 18 weeks postoperatively in rats of the ACLX group than in rats of the control and sham groups (p<0.001. In the ACLX group (compared to the sham and control groups, T2* values increased significantly first in the posterior horn of the medial meniscus at 4 weeks (p = 0.001, then in the anterior horn of the medial meniscus at 13 weeks (p<0.001, and began to increase significantly in the femoral subchondral bone marrow at 13 weeks (p = 0.043. CONCLUSION: Quantitative MR T2* measurements of OA-related tissues are feasible. Sequential change in T2* over time in cartilage, meniscus, and subchondral bone marrow were documented. This information could be potentially useful for in vivo monitoring of disease progression.

  18. The Role of Sirtuins in Cartilage Homeostasis and Osteoarthritis.

    Science.gov (United States)

    Dvir-Ginzberg, Mona; Mobasheri, Ali; Kumar, Ashok

    2016-07-01

    The past decade has witnessed many advances in the understanding of sirtuin biology and related regulatory circuits supporting the capacity of these proteins to serve as energy-sensing molecules that contribute to healthspan in various tissues, including articular cartilage. Hence, there has been a significant increase in new investigations that aim to elucidate the mechanisms of sirtuin function and their roles in cartilage biology, skeletal development, and pathologies such as osteoarthritis (OA), rheumatoid arthritis (RA), and intervertebral disc degeneration (IVD). The majority of the work carried out to date has focused on SIRT1, although SIRT6 has more recently become a focus of some investigations. In vivo work with transgenic mice has shown that Sirt1 and Sirt6 are essential for maintaining cartilage homeostasis and that the use of sirtuin-activating molecules such as resveratrol may have beneficial effects on cartilage anabolism. Current thinking is that SIRT1 exerts positive effects on cartilage by encouraging chondrocyte survival, especially under stress conditions, which may provide a mechanism supporting the use of sirtuin small-molecule activators (STACS) for future therapeutic interventions in OA and other degenerative pathologies of joints, especially those that involve articular cartilage. PMID:27289467

  19. Computational aspects in mechanical modeling of the articular cartilage tissue.

    Science.gov (United States)

    Mohammadi, Hadi; Mequanint, Kibret; Herzog, Walter

    2013-04-01

    This review focuses on the modeling of articular cartilage (at the tissue level), chondrocyte mechanobiology (at the cell level) and a combination of both in a multiscale computation scheme. The primary objective is to evaluate the advantages and disadvantages of conventional models implemented to study the mechanics of the articular cartilage tissue and chondrocytes. From monophasic material models as the simplest form to more complicated multiscale theories, these approaches have been frequently used to model articular cartilage and have contributed significantly to modeling joint mechanics, addressing and resolving numerous issues regarding cartilage mechanics and function. It should be noted that attentiveness is important when using different modeling approaches, as the choice of the model limits the applications available. In this review, we discuss the conventional models applicable to some of the mechanical aspects of articular cartilage such as lubrication, swelling pressure and chondrocyte mechanics and address some of the issues associated with the current modeling approaches. We then suggest future pathways for a more realistic modeling strategy as applied for the simulation of the mechanics of the cartilage tissue using multiscale and parallelized finite element method.

  20. Cartilage change after arthroscopic repair for an isolated meniscal tear.

    Science.gov (United States)

    Soejima, Takashi; Murakami, Hidetaka; Inoue, Takashi; Kanazawa, Tomonoshin; Katouda, Michihiro; Nagata, Kensei

    2005-01-01

    To investigate the direct effect to the cartilage caused by the meniscal repair, we examined patients who underwent an isolated meniscal repair without any other abnormalities by arthroscopic examination. A total of 17 patients were examined by second-look arthroscopy after an average interval of 9 months from the meniscal repair, and have been evaluated the status of the repaired meniscus and of the relative femoral condylar cartilage. Changes in the severity of the cartilage lesion between at the time of meniscal repair and the time of the second-look arthroscopy were considered based on the status of the repaired meniscus. Regardless of the healing status of the repair site, it was possible to prevent degeneration in the cartilage in 9 of the 10 patients who demonstrated no degeneration in the meniscal body. Of the 7 patients who demonstrated degeneration in the meniscal body, progression in cartilage degeneration was noted as 1 grade in 2 patients and 2 grades in another 3 patients. Even in those in which stable fusion of the repair site was achieved, the condition of the inner meniscal body was not necessarily maintained favorably in all cases, indicating that degeneration in the meniscal body was a risk factor for cartilage degeneration. It was concluded that recovery could not be expected even at 9 months after the repair if the lesion had already demonstrated degeneration in the meniscal body at the time of repair.

  1. Depth Dependence of Shear Properties in Articular Cartilage

    Science.gov (United States)

    Buckley, Mark; Gleghorn, Jason; Bonassar, Lawrence; Cohen, Itai

    2007-03-01

    Articular cartilage is a highly complex and heterogeneous material in its structure, composition and mechanical behavior. Understanding these spatial variations is a critical step in designing replacement tissue and developing methods to diagnose and treat tissue affected by damage or disease. Existing techniques in particle image velocimetry (PIV) have been used to map the shear properties of complex materials; however, these methods have yet to be applied to understanding shear behavior in cartilage. In this talk, we will show that confocal microscopy in conjunction with PIV techniques can be used to determine the depth dependence of the shear properties of articular cartilage. We will show that the shear modulus of this tissue varies by over an order of magnitude over its depth, with the least stiff region located about 200 microns from the surface. Furthermore, our data indicate that the shear strain profile of articular cartilage is sensitive to both the degree of compression and the total applied shear strain. In particular, we find that cartilage strain stiffens most dramatically in a region 200-500 microns below the surface. Finally, we will describe a physical model that accounts for this behavior by taking into account the local buckling of collagen fibers just below the cartilage surface and present second harmonic generation (SHG) imaging data addressing the collagen orientation before and after shear.

  2. Prevention of cartilage dehydration in imaging studies with a customized humidity chamber.

    Science.gov (United States)

    Choo, Ryan J; Firminger, Colin; Müller, Ralph; Stok, Kathryn S

    2013-09-01

    Quantitative three-dimensional imaging methods such as micro-computed tomography (μCT) allow for the rapid and comprehensive evaluation of cartilage and bone in animal models, which can be used for drug development and related research in arthritis. However, when imaging fresh cartilage tissue in air, a common problem is tissue dehydration which causes movement artifact in the resulting images. These artifacts distort scans and can render them unusable, leading to a considerable loss of time and effort with sample preparation and measurement. The sample itself is also irretrievably damaged by the dehydration, often unable to return to its full tissue thickness upon rehydration. Additionally, imaging with ionic contrast agents such as Hexabrix(TM) must be performed in air, otherwise the agent will be washed out if immersed in a liquid. The first goal of this study was to design a customized humidity chamber to maintain cartilage hydration without the need for immersion. Following this, the use of the humidity chamber during a synchrotron radiation-μCT scan was validated and its performance evaluated. Results showed that the loss of fluid film volume is associated with scanning at low humidity (87%), and can be avoided using the humidity chamber. Coupling this technology with advances in synchrotron imaging (e.g., phase contrast imaging) or contrast agents is promising.

  3. Effects of phototherapy on cartilage structure and inflammatory markers in an experimental model of osteoarthritis

    Science.gov (United States)

    Oliveira, Poliani; Santos, Anderson Amaro; Rodrigues, Tamara; Tim, Carla Roberta; Pinto, Karina Zambone; Magri, Angela Maria Paiva; Fernandes, Kelly Rossetti; Mattiello, Stela M.; Parizotto, Nivaldo Antonio; Anibal, Fernanda Freitas; Rennó, Ana Claudia Muniz

    2013-12-01

    The aim of this study was to evaluate the effects of laser phototherapy on the degenerative modifications on the articular cartilage after the anterior cruciate ligament transection (ACLT) in the knee of rats. Eighty male rats (Wistar) were distributed into four groups: intact control group (IG), injured control group (CG), injured laser treated group at 10 J/cm2 (L10), and injured laser treated group at 50 J/cm2 (L50). Animals were distributed into two subgroups, sacrificed in 5 and 8 weeks postsurgery. The ACLT was used to induce knee osteoarthritis in rats. After 2 weeks postsurgery, laser phototherapy initiated and it was performed for 15 and 30 sessions. The histological findings revealed that laser irradiation, especially at 10 J/cm2, modulated the progression of the degenerative process, showing a better cartilage structure and lower number of condrocytes compared to the other groups. Laser phototherapy was not able to decrease the degenerative process measured by Mankin score and prevent the increase of cartilage thickness related to the degenerative process. Moreover, it did not have any effect in the biomodulation of the expression of markers IL1β, tumor necrosis factor-α, and metalloprotein-13. Furthermore, laser irradiated animals, at 50 J/cm2 showed a lower amount of collagen type 1.

  4. Prevention of cartilage dehydration in imaging studies with a customized humidity chamber

    Science.gov (United States)

    Choo, Ryan J.; Firminger, Colin; Müller, Ralph; Stok, Kathryn S.

    2013-09-01

    Quantitative three-dimensional imaging methods such as micro-computed tomography (μCT) allow for the rapid and comprehensive evaluation of cartilage and bone in animal models, which can be used for drug development and related research in arthritis. However, when imaging fresh cartilage tissue in air, a common problem is tissue dehydration which causes movement artifact in the resulting images. These artifacts distort scans and can render them unusable, leading to a considerable loss of time and effort with sample preparation and measurement. The sample itself is also irretrievably damaged by the dehydration, often unable to return to its full tissue thickness upon rehydration. Additionally, imaging with ionic contrast agents such as HexabrixTM must be performed in air, otherwise the agent will be washed out if immersed in a liquid. The first goal of this study was to design a customized humidity chamber to maintain cartilage hydration without the need for immersion. Following this, the use of the humidity chamber during a synchrotron radiation-μCT scan was validated and its performance evaluated. Results showed that the loss of fluid film volume is associated with scanning at low humidity (87%), and can be avoided using the humidity chamber. Coupling this technology with advances in synchrotron imaging (e.g., phase contrast imaging) or contrast agents is promising.

  5. A comparative study of outcome of ossiculoplasty using cartilage graft, bone and different alloplasts in chronic otitis media

    Directory of Open Access Journals (Sweden)

    Sougata Mahanty

    2015-01-01

    Full Text Available Objective: The objective was to determine which material, among autologous cartilage, autologous incus and partial ossicular replacement prosthesis (PORP, gives better postoperative hearing result in ossiculoplasty. Study Design: Nonrandomized prospective cohort (longitudinal study. Settings: Tertiary referral center. Materials and Methods: Patients were selected from outpatients department with the clinical diagnosis of chronic suppurative otitis media with cholesteatoma or granulation tissue. Patients underwent necessary preoperative investigations including pure tone audiometry (PTA. Total 67 patients were selected for this study, among them 12 patients did not fit the selection criteria and 5 patients lost during follow-up. Hence, total 50 patients were taken in the study group. Intervention: Ossiculoplasty with cartilage, incus and PORP after modified radical mastoidectomy. Main Outcome Measure: Hearing results were measured by PTA-air bone gap (PTA-ABG after 6 months of operation. Results: Selecting the criteria <20 dB ABG as success when stapes superstructure is present, cartilage has 60% success rate, incus has 73.68%, and PORP has 56.25% success. Extrusion rate of different prosthesis shows, PORP has 25%, cartilage has 20% extrusion. Incus has the lowest (5.26% extrusion rate. Conclusion: Among the ossiculoplasty materials, autologous incus gives best postoperative hearing gain and lowest extrusion rate.

  6. The significance of electromechanical and osmotic forces in the nonequilibrium swelling behavior of articular cartilage in tension.

    Science.gov (United States)

    Grodzinsky, A J; Roth, V; Myers, E; Grossman, W D; Mow, V C

    1981-11-01

    Studies were conducted of some of the nonequilibrium, electrolyte-activated, electromechanical and osmotic processes that can affect the tensile properties of articular cartilage. We measured changes in tensile force that were induced by altering the ionic environment of strips of cartilage held at fixed length. We compared the kinetics of changes in these macroscopically measured isometric tensile forces to theoretical estimates of the time constants that characterize the underlying physical and chemical mechanisms occurring within the cartilage specimens during the experiment. Changes in the tensile force induced by changing the bath neutral salt concentration surrounding the specimen appear to be rate-limited by the diffusion of the salt into the specimen. That is, the mechanical stress relaxation process resulting from changes in salt concentration seems to be occurring at least as rapidly as the diffusion of salt into the matrix. When the bath concentration of CaCl2 or HCl is varied, the rate of change in the resulting isometric stresses indicates that Ca++ and H+ ions are binding to the cartilage matrix macromolecules. PMID:7311487

  7. Development and potential of a biomimetic chitosan/type Ⅱ collagen scaffold for cartilage tissue engineering

    Institute of Scientific and Technical Information of China (English)

    SHI De-hai; CAI Dao-zhang; ZHOU Chang-ren; RONG Li-min; WANG Kun; XU Yi-chun

    2005-01-01

    Background Damaged articular cartilage has very limited capacity for spontaneous healing. Tissue engineering provides a new hope for functional cartilage repair. Creation of an appropriate cell carrier is one of the critical steps for successful tissue engineering. With the supposition that a biomimetic construct might promise to generate better effects, we developed a novel composite scaffold and investigated its potential for cartilage tissue engineering. Methods Chitosan of 88% deacetylation was prepared via a modified base reaction procedure. A freeze-drying process was employed to fabricate a three-dimensional composite scaffold consisting of chitosan and type Ⅱcollagen. The scaffold was treated with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide. Ultrastructure and tensile strength of the matrix were carried out to assess its physico-chemical properties. After subcutaneous implantation in rabbits, its in vivo biocompatibility and degradability of the scaffold were determined. Its capacity to sustain chondrocyte growth and biosynthesis was evaluated through cell-scaffold co-culture in vitro. Results The fabricated composite matrix was porous and sponge-like with interconnected pores measuring from 100-250 μm in diameter. After cross-linking, the scaffold displayed enhanced tensile strength. Subcutaneous implantation results indicated the composite matrix was biocompatible and biodegradable. In intro cell-scaffold culture showed the scaffold sustained chondrocyte proliferation and differentiation, and maintained the spheric chondrocytic phenotype. As indicated by immunohistochemical staining, the chondrocytes synthesized type Ⅱ collagen. Conclusions Chitosan and type Ⅱ collagen can be well blended and developed into a porous 3-D biomimetic matrix. Results of physico-chemical and biological tests suggest the composite matrix satisfies the constraints specified for a tissue-engineered construct and may be used as a chondrocyte

  8. Effect of nitric oxide synthase inhibitor on proteoglycan metabolism in repaired articular cartilage in rabbits

    Institute of Scientific and Technical Information of China (English)

    孙炜; 金大地; 王吉兴; 秦立赟; 刘晓霞

    2003-01-01

    Objective: To study the effect of nitric oxide synthase inhibitor, S-methyl thiocarbamate (SMT), on proteoglycan metabolism in repaired articular cartilage in rabbits. Methods: Twenty-four male New Zealand white rabbits, aged 8 months and weighing 2.5 kg±0.2 kg, were used in this study. Cartilage defects in full thickness were created on the intercondylar articular surface of bilateral femurs of all the rabbits. Then the rabbits were randomly divided into 3 groups (n=8 in each group). The defects in one group were filled with fibrin glue impregnated with recombinant human bone morphogenetic protein-2 (rhBMP-2, BMP group), in one group with fibrin glue impregnated with rhBMP-2 and hypodermic injection with SMT (SMT group) and in the other group with nothing (control group). All the animals were killed at one year postoperatively. The tissue sections were stained with safranine O-fast green and analyzed by Quantiment 500 system to determine the content of glycosaminoglycan through measuring the percentage of safranine O-stained area, the thickness of cartilages and the mean gray scale (average stain intensity). Radiolabelled sodium sulphate (Na235SO4) was used to assess the proteoglycan synthesis. Results: At one year postoperatively, the percentage of safranine O-stained area, the mean gray scale and the cartilage thickness of the repaired tissues in SMT group were significantly higher than those of BMP group (P<0.01) and the control group (P<0.05). Result of incorporation of Na235SO4 showed that the proteoglycan synthesis in SMT group was higher than those of BMP group and the control group (P<0.01). Conclusions: SMT, a nitric oxide synthase inhibitor, can significantly increase the content of glycosaminoglycan and proteoglycan synthesis, and computer-based image analysis is a reliable method for evaluating proteoglycan metabolism.

  9. Lineage plasticity and cell biology of fibrocartilage and hyaline cartilage: Its significance in cartilage repair and replacement

    Energy Technology Data Exchange (ETDEWEB)

    Freemont, Anthony J. [Regenerative Medicine Research Group, University of Manchester, England (United Kingdom)]. E-mail: Tony.freemont@man.ac.uk; Hoyland, Judith [Regenerative Medicine Research Group, University of Manchester, England (United Kingdom)

    2006-01-15

    Cartilage repair is a major goal of modern tissue engineering. To produce novel engineered implants requires a knowledge of the basic biology of the tissues that are to be replaced or reproduced. Hyaline articular cartilage and meniscal fibrocartilage are two tissues that have excited attention because of the frequency with which they are damaged. A basic strategy is to re-engineer these tissues ex vivo by stimulating stem cells to differentiate into the cells of the mature tissue capable of producing an intact functional matrix. In this brief review, the sources of cells for tissue engineering cartilage and the culture conditions that have promoted differentiation are discussed within the context of natural cartilage repair. In particular, the role of cell density, cytokines, load, matrices and oxygen tension are discussed.

  10. A biochemical model for characterising the surface-active phospolipid bilayer of articular cartilage relative to acid-base equilibrium

    Directory of Open Access Journals (Sweden)

    Z. Pawlak

    2008-01-01

    Full Text Available Purpose: This paper, addresses the question of how changes in acid - base equilibrium influence change in thecharge density of the phospholipid bilayer on articular cartilage surfaces during lubrication.Design/methodology/approach: Liposomes have been used to mimic biological phospholipid membranes onarticular cartilage surface where proteins are bounded, ions are transported, energy is transducted, and cellular processestake place. The charge density of the membrane was determined as a function of pH and electrolyte concentration fromthe microelectrophoretic method. Liposome membrane was prepared as an aqueous solution of NaCl under variouspH conditions. Microelectrophoresis was used to examine the local acid-base equilibrium of the electrolytes with themembrane surface, which can be considered to model the phospholipids interface in articular cartilage.Findings: The adsorbed ions (H+, OH-, Na+, Cl- which are present in the electrically charged solutions of liposomemembrane comprising phosphatidycholine (PC, were found to exhibit pH-responsive quasi-periodic behavior.Research limitations/implications: We have established that the acid-base dissociation behavior inphospholipid bilayers of articular cartilage is a key to understanding biolubrication processes. For example,previous investigators found that the formation of the multilayer of polyisopeptide/hyaluronic acid depends onsurface properties such as film thickness, surface friction, surface wetability; wetness and swelling behavior.Future work should consider the adsorption of polyelectrolyte ions, e.g., the glycoprotein lubricin and hyaluronan,on the liposome membrane surface in the presence of H+ and OH- ions.Originality/value: A novel model of the joints’ phospholipid bilayers has been created using liposome membraneThis model can be applied in the investigation of polyelectrolyte ions such as lubricin, in articular cartilage. Wehave demonstrated that the acid-base processes on

  11. Lizard tail regeneration: regulation of two distinct cartilage regions by Indian hedgehog.

    Science.gov (United States)

    Lozito, Thomas P; Tuan, Rocky S

    2015-03-15

    Lizards capable of caudal autotomy exhibit the remarkable ability to "drop" and then regenerate their tails. However, the regenerated lizard tail (RLT) is known as an "imperfect replicate" due to several key anatomical differences compared to the original tail. Most striking of these "imperfections" concerns the skeleton; instead of the vertebrae of the original tail, the skeleton of the RLT takes the form of an unsegmented cartilage tube (CT). Here we have performed the first detailed staging of skeletal development of the RLT CT, identifying two distinct mineralization events. CTs isolated from RLTs of various ages were analyzed by micro-computed tomography to characterize mineralization, and to correlate skeletal development with expression of endochondral ossification markers evaluated by histology and immunohistochemistry. During early tail regeneration, shortly after CT formation, the extreme proximal CT in direct contact with the most terminal vertebra of the original tail develops a growth plate-like region that undergoes endochondral ossification. Proximal CT chondrocytes enlarge, express hypertrophic markers, including Indian hedgehog (Ihh), apoptose, and are replaced by bone. During later stages of tail regeneration, the distal CT mineralizes without endochondral ossification. The sub-perichondrium of the distal CT expresses Ihh, and the perichondrium directly calcifies without cartilage growth plate formation. The calcified CT perichondrium also contains a population of stem/progenitor cells that forms new cartilage in response to TGF-β stimulation. Treatment with the Ihh inhibitor cyclopamine inhibited both proximal CT ossification and distal CT calcification. Thus, while the two mineralization events are spatially, temporally, and mechanistically very different, they both involve Ihh. Taken together, these results suggest that Ihh regulates CT mineralization during two distinct stages of lizard tail regeneration.

  12. Atomic force microscopy measurements of bacterial adhesion and biofilm formation onto clay-sized particles

    Science.gov (United States)

    Huang, Qiaoyun; Wu, Huayong; Cai, Peng; Fein, Jeremy B.; Chen, Wenli

    2015-11-01

    Bacterial adhesion onto mineral surfaces and subsequent biofilm formation play key roles in aggregate stability, mineral weathering, and the fate of contaminants in soils. However, the mechanisms of bacteria-mineral interactions are not fully understood. Atomic force microscopy (AFM) was used to determine the adhesion forces between bacteria and goethite in water and to gain insight into the nanoscale surface morphology of the bacteria-mineral aggregates and biofilms formed on clay-sized minerals. This study yields direct evidence of a range of different association mechanisms between bacteria and minerals. All strains studied adhered predominantly to the edge surfaces of kaolinite rather than to the basal surfaces. Bacteria rarely formed aggregates with montmorillonite, but were more tightly adsorbed onto goethite surfaces. This study reports the first measured interaction force between bacteria and a clay surface, and the approach curves exhibited jump-in events with attractive forces of 97 ± 34 pN between E. coli and goethite. Bond strengthening between them occurred within 4 s to the maximum adhesion forces and energies of -3.0 ± 0.4 nN and -330 ± 43 aJ (10-18 J), respectively. Under the conditions studied, bacteria tended to form more extensive biofilms on minerals under low rather than high nutrient conditions.

  13. Atomic force microscopy measurements of bacterial adhesion and biofilm formation onto clay-sized particles.

    Science.gov (United States)

    Huang, Qiaoyun; Wu, Huayong; Cai, Peng; Fein, Jeremy B; Chen, Wenli

    2015-11-20

    Bacterial adhesion onto mineral surfaces and subsequent biofilm formation play key roles in aggregate stability, mineral weathering, and the fate of contaminants in soils. However, the mechanisms of bacteria-mineral interactions are not fully understood. Atomic force microscopy (AFM) was used to determine the adhesion forces between bacteria and goethite in water and to gain insight into the nanoscale surface morphology of the bacteria-mineral aggregates and biofilms formed on clay-sized minerals. This study yields direct evidence of a range of different association mechanisms between bacteria and minerals. All strains studied adhered predominantly to the edge surfaces of kaolinite rather than to the basal surfaces. Bacteria rarely formed aggregates with montmorillonite, but were more tightly adsorbed onto goethite surfaces. This study reports the first measured interaction force between bacteria and a clay surface, and the approach curves exhibited jump-in events with attractive forces of 97 ± 34 pN between E. coli and goethite. Bond strengthening between them occurred within 4 s to the maximum adhesion forces and energies of -3.0 ± 0.4 nN and -330 ± 43 aJ (10(-18) J), respectively. Under the conditions studied, bacteria tended to form more extensive biofilms on minerals under low rather than high nutrient conditions.

  14. A method for measurement of the bubble formation threshold in biological liquids.

    Science.gov (United States)

    Bjorno, L; Kornum, L O; Krag, P; Nielsen, C H; Paulev, P E

    1977-06-01

    Liquid under pressure is saturated with a given gas, such as argon, nitrogen, or air, by circulation through a column of gas exchangers. A sample of the gas-saturated liquid is isolated in a test chamber, the volume of which can be increased by means of a moving piston. The piston motion is cyclical with a variable frequency. Pressure in the test chamber is measured by means of a capacitive pressure pick-up. When the volume increase of the gas-saturated liquid in the test chamber is compensated for by the development of gas phase bubbles, the pressure decrease will stop; the recording device will show a pressure plateau, or a dip in the pressure-time course, depending on the velocity of the growth of the bubbles. Bubble formation threshold was independent of the frequency of the piston movement within frequency limits from 1 Hz down to 10(-3) Hz. Most experiements were carried out at a single frequency of 0.5 Hz. This new method appears to have advantages over previous ones.

  15. Cartilage Repair and Subchondral Bone Migration Using 3D Printing Osteochondral Composites: A One-Year-Period Study in Rabbit Trochlea

    Directory of Open Access Journals (Sweden)

    Weijie Zhang

    2014-01-01

    Full Text Available Increasing evidences show that subchondral bone may play a significant role in the repair or progression of cartilage damage in situ. However, the exact change of subchondral bone during osteochondral repair is still poorly understood. In this paper, biphasic osteochondral composite scaffolds were fabricated by 3D printing technology using PEG hydrogel and β-TCP ceramic and then implanted in rabbit trochlea within a critical size defect model. Animals were euthanized at 1, 2, 4, 8, 16, 24, and 52 weeks after implantation. Histological results showed that hyaline-like cartilage formed along with white smooth surface and invisible margin at 24 weeks postoperatively, typical tidemark formation at 52 weeks. The repaired subchondral bone formed from 16 to 52 weeks in a “flow like” manner from surrounding bone to the defect center gradually. Statistical analysis illustrated that both subchondral bone volume and migration area percentage were highly correlated with the gross appearance Wayne score of repaired cartilage. Therefore, subchondral bone migration is related to cartilage repair for critical size osteochondral defects. Furthermore, the subchondral bone remodeling proceeds in a “flow like” manner and repaired cartilage with tidemark implies that the biphasic PEG/β-TCP composites fabricated by 3D printing provides a feasible strategy for osteochondral tissue engineering application.

  16. Cartilage repair and subchondral bone migration using 3D printing osteochondral composites: a one-year-period study in rabbit trochlea.

    Science.gov (United States)

    Zhang, Weijie; Lian, Qin; Li, Dichen; Wang, Kunzheng; Hao, Dingjun; Bian, Weiguo; He, Jiankang; Jin, Zhongmin

    2014-01-01

    Increasing evidences show that subchondral bone may play a significant role in the repair or progression of cartilage damage in situ. However, the exact change of subchondral bone during osteochondral repair is still poorly understood. In this paper, biphasic osteochondral composite scaffolds were fabricated by 3D printing technology using PEG hydrogel and β-TCP ceramic and then implanted in rabbit trochlea within a critical size defect model. Animals were euthanized at 1, 2, 4, 8, 16, 24, and 52 weeks after implantation. Histological results showed that hyaline-like cartilage formed along with white smooth surface and invisible margin at 24 weeks postoperatively, typical tidemark formation at 52 weeks. The repaired subchondral bone formed from 16 to 52 weeks in a "flow like" manner from surrounding bone to the defect center gradually. Statistical analysis illustrated that both subchondral bone volume and migration area percentage were highly correlated with the gross appearance Wayne score of repaired cartilage. Therefore, subchondral bone migration is related to cartilage repair for critical size osteochondral defects. Furthermore, the subchondral bone remodeling proceeds in a "flow like" manner and repaired cartilage with tidemark implies that the biphasic PEG/β-TCP composites fabricated by 3D printing provides a feasible strategy for osteochondral tissue engineering application.

  17. A Study of Geological Formation on Different Sites in Batu Pahat, Malaysia Based On HVSR Method Using Microtremor Measurement

    Science.gov (United States)

    Noor, M. A. M.; Madun, A.; Kamarudin, A. F.; Daud, M. E.

    2016-07-01

    Geological formation is a one of information need to know during site reconnaissance. Conventional method like borehole has been known is very accurate to identify the formation of geology of a site. However, the problem of this technique is very expensive and not economical for large area. In the last decade, microtremor measurement has been introduced as an alternative technique and widely used in the geological formation study. Therefore, the aim in this study is to determine the geological formation underneath of surface in Batu Pahat district using microtremor measurement. There are two parameters have been carried out from microtremor measurement in term of natural frequency and HVSR curves images. Microtremor measurements are done conducted at 15 sites surrounding of Batu Pahat. Horizontal to vertical spectral ratio (HVSR) method was used for analyzing microtermor measurement data, to determine the natural frequency and also HVSR curves image. In this study, values of natural frequencies are used to classify the soil types with range in the between 0.93 to 5.35 Hz, meanwhile the pattern of HVSR curve images has been shown exists a few groups of soil types surrounding Batu Pahat district. Hence, microtremor measurement indirectly can be used as a one technique to add value in the site reconnaissance in the future.

  18. Quantitative T2 mapping of the patella at 3.0 T is sensitive to early cartilage degeneration, but also to loading of the knee

    International Nuclear Information System (INIS)

    Objective: The aim of the study was to explore the sensitivity and robustness of T2 mapping in the detection and quantification of early degenerative cartilage changes at the patella. Materials and methods: Forty-two patients (22 women, 20 men) with a mean age of 30.3 years and a symptomatic cartilage defect of ICRS grade ≤2 were examined using a 3 T MRI with an 8-channel knee coil. The cartilage lesion was graded based on high-resolution PD TSE and 3D isotropic TrueFISP images. T2 maps were calculated from a standard MESE-sequence, performed at the beginning and at the end of the scan (40 min in-between). Depending on the defect size, a region-of-interest (ROI) analysis was performed on 1–3 consecutive slices. Mean T2 values for the deep, superficial, and global layer as well as the zonal variation were compared among defect grades (ANOVA, post hoc Duncan-test) and over time (Student's t-test). Results: T2-measurements directly correlated with the extent of cartilage defect (ICRS grade) at all layers and at both time-points. However, correlations were closer for the second measurement at the end of the scan. In this unloaded state, differences in T2-values became more pronounced and were significant even between cartilage of normal appearance adjacent to the defect and healthy cartilage of control patients (both ICRS grade 0). In contrast, there were no such differences among grades in the zonal variation at any time. Conclusion: T2 mapping might be a sensitive method for the detection of early cartilage degeneration at the patella in the unloaded joint.

  19. Allogeneic Bone Marrow Transplant from MRL/MpJ Super-Healer Mice Does Not Improve Articular Cartilage Repair in the C57Bl/6 Strain.

    Directory of Open Access Journals (Sweden)

    Catherine A Leonard

    Full Text Available Articular cartilage has been the focus of multiple strategies to improve its regenerative/ repair capacity. The Murphy Roths Large (MRL/MpJ "super-healer" mouse demonstrates an unusual enhanced regenerative capacity in many tissues and provides an opportunity to further study endogenous cartilage repair. The objective of this study was to test whether the super-healer phenotype could be transferred from MRL/MpJ to non-healer C57Bl/6 mice by allogeneic bone marrow transplant.The healing of 2mm ear punches and full thickness cartilage defects was measured 4 and 8 weeks after injury in control C57Bl/6 and MRL/MpJ "super-healer" mice, and in radiation chimeras reconstituted with bone marrow from the other mouse strain. Healing was assessed using ear hole diameter measurement, a 14 point histological scoring scale for the cartilage defect and an adapted version of the Osteoarthritis Research Society International scale for assessment of osteoarthritis in mouse knee joints.Normal and chimeric MRL mice showed significantly better healing of articular cartilage and ear wounds along with less severe signs of osteoarthritis after cartilage injury than the control strain. Contrary to our hypothesis, however, bone marrow transplant from MRL mice did not confer improved healing on the C57Bl/6 chimeras, either in regards to ear wound healing or cartilage repair.The elusive cellular basis for the MRL regenerative phenotype still requires additional study and may possibly be dependent on additional cell types external to the bone marrow.

  20. Abnormal mandibular growth and the condylar cartilage.

    Science.gov (United States)

    Pirttiniemi, Pertti; Peltomäki, Timo; Müller, Lukas; Luder, Hans U

    2009-02-01

    Deviations in the growth of the mandibular condyle can affect both the functional occlusion and the aesthetic appearance of the face. The reasons for these growth deviations are numerous and often entail complex sequences of malfunction at the cellular level. The aim of this review is to summarize recent progress in the understanding of pathological alterations occurring during childhood and adolescence that affect the temporomandibular joint (TMJ) and, hence, result in disorders of mandibular growth. Pathological conditions taken into account are subdivided into (1) congenital malformations with associated growth disorders, (2) primary growth disorders, and (3) acquired diseases or trauma with associated growth disorders. Among the congenital malformations, hemifacial microsomia (HFM) appears to be the principal syndrome entailing severe growth disturbances, whereas growth abnormalities occurring in conjunction with other craniofacial dysplasias seem far less prominent than could be anticipated based on their often disfiguring nature. Hemimandibular hyperplasia and elongation undoubtedly constitute the most obscure conditions that are associated with prominent, often unilateral, abnormalities of condylar, and mandibular growth. Finally, disturbances of mandibular growth as a result of juvenile idiopathic arthritis (JIA) and condylar fractures seem to be direct consequences of inflammatory and/or mechanical damage to the condylar cartilage. PMID:19164410

  1. Rehabilitation after cell transplantation for cartilage defects.

    Science.gov (United States)

    Deszczynski, J; Slynarski, K

    2006-01-01

    Rehabilitation is a key element of successful treatment of cartilage defects with cell transplantation. The process of graft maturation takes approximately 18 months and cannot be accelerated, but requires carefully introduced steps leading to early recovery of joint function. Rehabilitation starts at 8 hours after surgery with the continuous passive motion (CPM) exercises and physiotherapy. For the first 6 weeks, patients continue with CPM in the range of 0 degrees to 45 degrees for femoral and tibial defects and 0 degrees to 30 degrees for patellofemoral joint reconstruction. Isometric muscle training and scar manual therapy are introduced. Patients are allowed to weight-bear as tolerated from the second week after surgery. After this initial phase, from 6 to 8 weeks after surgery, rehabilitation is accelerated with increased load-bearing and progressive range of motion to full flexion. Usually patients are able to walk without crutches in this time. Proprioceptive training is introduced with the advance of pain-free full range of motion and no discomfort with full weight-bearing. At 6 months after surgery, most patients recover joint function, making it possible for them to return to daily living activities. However, they need to continue with muscle, proprioceptive, and sports-specific rehabilitation exercises. The rehabilitation process is complicated, requiring close cooperation between the patient and surgeon-physiotherapist team to understand the symptoms and address them in a timely fashion. PMID:16504734

  2. Evaluation of the relationship between T1ρ and T2 values and patella cartilage degeneration in patients of the same age group

    International Nuclear Information System (INIS)

    Highlights: •This prospective cohort study investigated the association between the T1ρ and T2 values and the progression of cartilage degeneration in patients of the same age group. In this study, to the best of our knowledge, this is the first report to compare the T1ρ and T2 values between normal and OA knees within the same age group and to further investigate the relationship between the degree of cartilage degeneration and the T1ρ and T2 values in OA-grading groups of the same age. Our study confirmed that T1ρ and T2 mapping can be used to quantitatively evaluate the degree of patella cartilage degeneration in patients within the same age group.. -- Abstract: Objective: The aim of this study was to investigate the association between the T1ρ and T2 values and the progression of cartilage degeneration in patients of the same age group. Materials and methods: Sagittal T1ρ and T2 mapping and three-dimensional (3D) gradient-echo images were obtained from 78 subjects with medial knee osteoarthritis (OA). The degree of patella cartilage degeneration was classified into four groups using MRI-based grading: apparently normal cartilage, mild OA, moderate OA, and severe OA group. We measured the T1ρ and T2 values (ms) in the regions of interest set on the full-thickness patella cartilage. Then, we analyzed the relationship between the T1ρ and T2 values and the degree of patella cartilage degeneration. Results: There were no significant differences in age among the four groups. Both the T1ρ and T2 values showed a positive correlation with the degree of OA progression (ρ = 0.737 and ρ = 0.632, respectively). By comparison between the apparently normal cartilage and the mild OA groups, there were significant differences in the T1ρ mapping, but not in the T2 mapping. Conclusions: Our study confirmed that T1ρ and T2 mapping can quantitatively evaluate the degree of patella cartilage degeneration in patients within the same age group

  3. A Quantitative Comparative Study Measuring Consumer Satisfaction Based on Health Record Format

    Science.gov (United States)

    Moore, Vivianne E.

    2013-01-01

    This research study used a quantitative comparative method to investigate the relationship between consumer satisfaction and communication based on the format of health record. The central problem investigated in this research study related to the format of health record used and consumer satisfaction with care provided and effect on communication…

  4. Further Insight into the Depth-Dependent Microstructural Response of Cartilage to Compression Using a Channel Indentation Technique

    Directory of Open Access Journals (Sweden)

    Ashvin Thambyah

    2013-01-01

    Full Text Available Stress relaxation and structural analysis were used to investigate the zonally differentiated microstructural response to compression of the integrated cartilage-on-bone tissue system. Fifteen cartilage-on-bone samples were divided into three equal groups and their stress relaxation responses obtained at three different levels of axial compressive strain defined as low (~20%, medium (~40% and high (~60%. All tests were performed using a channel indenter which included a central relief space designed to capture the response of the matrix adjacent to the directly loaded regions. On completion of each stress relaxation test and while maintaining the imposed axial strain, the samples were formalin fixed, decalcified, and then sectioned for microstructural analysis. Chondron aspect ratios were used to determine the extent of relative strain at different zonal depths. The stress relaxation response of cartilage to all three defined levels of axial strain displayed an initial highly viscous response followed by a significant elastic response. Chondron aspect ratio measurements showed that at the lowest level of compression, axial deformation was confined to the superficial cartilage layer, while in the medium and high axial strain samples the deformation extended into the midzone. The cells in the deep zone remained undeformed for all compression levels.

  5. Good results five years after surgical management of anterior cruciate ligament tears, and meniscal and cartilage injuries.

    Science.gov (United States)

    Osti, Leonardo; Papalia, Rocco; Del Buono, Angelo; Amato, Cirino; Denaro, Vincenzo; Maffulli, Nicola

    2010-10-01

    In athletes with anterior cruciate ligament (ACL) tears combined with meniscal and cartilage injuries, the goals are to restore knee laxity and relieve symptoms, while long-term goals are the return to pre-injury sport activity and to prevent onset of degenerative changes. We compared the post-operative (minimum 5 years) clinical and radiological outcomes of 50 patients, similar for ACL rupture and meniscal tears, but different for the grade of cartilage lesion. The patient population was divided into two groups similar for ACL reconstruction and surgical meniscal management. Group 1 included 25 patients undergoing microfracture management of grade III-IV cartilage lesions, while Group 2 included 25 patients with grade I-II cartilage lesions, managed by radiofrequency. Comparing pre- and post-operative status, Lachman test, pivot shift values and KT 1000 side to side difference measurements improved significantly (0.05) at the intermediate and latest assessments. At both post-operative appointments, in both groups, the average Lysholm score and IKDC ranking rates improved significantly (lesions, microfractures give excellent short-term clinical and functional improvement but do not prevent the evolution of degenerative changes.

  6. Histology of porcine nasal cartilage grafts following Nd:YAG (1320 nm) laser-mediated reshaping: effects of sequential irradiation

    Science.gov (United States)

    Kim, Hong K.; Wong, Brian J.; Benton, Hilary P.; Liaw, Lih-Huei L.; Nelson, J. Stuart; Milner, Thomas E.

    2001-07-01

    Mechanically deformed morphologic cartilage grafts undergo temperature dependent stress relaxation during sustained laser irradiation resulting in stable shape changes. In this study, the porcine nasal septal cartilage specimens were evaluated histologically following laser mediated reshaping using H&E. Cartilage specimens were irradiated with light emitted from a Nd:YAG laser (25 W/cm2, 1 = 1.32 mm) while recording simultaneously radiometric surface temperature, internal stress, and backscattered light intensity from a probe laser. Each specimen received one, two, or three sequential laser exposures. The duration of each exposure was determined from real-time measurements of characteristic changes in backscattered light intensity that correlate with accelerated stress relaxation. A five minute time interval between each laser exposures allowed the cartilage specimen to return to thermal equilibrium. Specimens were then fixed in formalin, serially dehydrated in ethanol, embedded in paraffin, and sectioned with a microtome for histologic examination using light microscopy. Large variation in native tissue histology was observed among individual tissue samples, and vascular were identified in several specimens. Large lacunae with shrunken chondrocytes were identified along with cells with pyknotic nuclei, although these histologic observations did not correlate with the degree of laser exposure. These observations are discussed.

  7. The Relationship between MR Parameters and Biomechanical Quantities of Loaded Human Articular Cartilage in Osteoarthritis: An In-Vitro Study

    Science.gov (United States)

    Juráš, V.; Szomolányi, P.; Gäbler, S.; Frollo, I.; Trattnig, S.

    2009-01-01

    The aim of this study was to assess the changes in MRI parameters during applied load directly in MR scanner and correlate these changes with biomechanical parameters of human articular cartilage. Cartilage explants from patients who underwent total knee replacement were examined in the micro-imaging system in 3T scanner. Respective MRI parameters (T1 without- and T1 with contrast agent as a marker of proteoglycan content, T2 as a marker of collagen network anisotropy and ADC as a measure of diffusivity) were calculated in pre- and during compression state. Subsequently, these parameters were compared to the biomechanical properties of articular cartilage, instantaneous modulus (I), equilibrium modulus (Eq) and time of tissue relaxation (τ). Significant load-induced changes of T2 and ADC were recorded. High correlation between T1Gd and I (r = 0.6324), and between ADC and Eq (r = -0.4884) was found. Multi-parametric MRI may have great potential in analyzing static and dynamic biomechanical behavior of articular cartilage in early stages of osteoarthritis (OA).

  8. Dynamic Response of Femoral Cartilage in Knees With Unicompartmental Osteoarthritis

    Directory of Open Access Journals (Sweden)

    A. Vidal-Lesso

    2011-08-01

    Full Text Available The objective of the present work was to determine the dynamic indentation response, stiffness and relaxation curvesfor the shear and the bulk modulus of femoral knee cartilage with no visual damage in cases under unicompartmentalosteoarthritis.A cyclic displacement of 0.5 mm in axial direction was applied with a 3 mm plane-ended cylindrical indenter at specificpoints in the femoral knee cartilage specimens of seven patients with unicompartmental osteoarthritis (UOA. Theindentation force over time was recorded and next the maximum stiffness in all cycles was obtained and compared.Also, the relaxation curves for the shear and the bulk modulus of cartilage were obtained in this work.A decrease in the maximum indentation force was observed comparing between indentation cycles; it was of 6.75 ±0.71% from cycle 1 to cycle 2 and 4.70 ± 0.31% for cycle 2 to cycle 3. Stiffness values changed with a mean of 3.35 ±0.39% from cycle 1 to cycle 2 and 1.40 ± 0.71% from cycle 2 to cycle 3. Moreover, relaxation curves for the shearmodulus and the bulk modulus showed the nonlinear behavior of articular cartilage with UOA.Our results showed that cartilage specimens with no visual damage in UOA preserve a nonlinear viscoelastic behaviorand its stiffness increases through the loading cycles. Our work provides experimental values for generating a morerealistic cartilage behavior than those currently used in computer cartilage models for the study of UOA.

  9. Biochemical composition of the superficial layer of articular cartilage.

    Science.gov (United States)

    Crockett, R; Grubelnik, A; Roos, S; Dora, C; Born, W; Troxler, H

    2007-09-15

    To gain more information on the mechanism of lubrication in articular joints, the superficial layer of bovine articular cartilage was mechanically removed in a sheet of ice that formed on freezing the cartilage. Freeze-dried samples contained low concentrations of chondroitin sulphate and protein. Analysis of the protein by SDS PAGE showed that the composition of the sample was comparable to that of synovial fluid (SF). Attenuated total reflection infrared (ATR-IR) spectroscopy of the dried residue indicated that the sample contained mostly hyaluronan. Moreover, ATR-IR spectroscopy of the upper layer of the superficial layer, adsorbed onto silicon, showed the presence of phospholipids. A gel could be formed by mixing hyaluronan and phosphatidylcholine in water with mechanical properties similar to those of the superficial layer on cartilage. Much like the superficial layer of natural cartilage, the surface of this gel became hydrophobic on drying out. Thus, it is proposed that the superficial layer forms from hyaluronan and phospholipids, which associate by hydrophobic interactions between the alkyl chains of the phospholipids and the hydrophobic faces of the disaccharide units in hyaluronan. This layer is permeable to material from the SF and the cartilage, as shown by the presence of SF proteins and chondroitin sulphate. As the cartilage dries out after removal from the joint, the phospholipids migrate towards the surface of the superficial layer to reduce the surface tension. It is also proposed that the highly efficient lubrication in articular joints can, at least in part, be attributed to the ability of the superficial layer to adsorb and hold water on the cartilage surface, thus creating a highly viscous boundary protection.

  10. Multichannel transceiver dual-tuned RF coil for proton/sodium MR imaging of knee cartilage at 3 T.

    Science.gov (United States)

    Kim, Jung-Hwan; Moon, Chan Hong; Park, Bum-Woo; Furlan, Alessandro; Zhao, Tiejun; Bae, Kyongtae T

    2012-05-01

    Sodium magnetic resonance (MR) imaging is a promising technique for detecting changes of proteoglycan (PG) content in cartilage associated with knee osteoarthritis. Despite its potential clinical benefit, sodium MR imaging in vivo is challenging because of intrinsically low sodium concentration and low MR signal sensitivity. Some of the challenges in sodium MR imaging may be eliminated by the use of a high-sensitivity radiofrequency (RF) coil, specifically, a dual-tuned (DT) proton/sodium RF coil which facilitates the co-registration of sodium and proton MR images and the evaluation of both physiochemical and structural properties of knee cartilage. Nevertheless, implementation of a DT proton/sodium RF coil is technically difficult because of the coupling effect between the coil elements (particularly at high field) and the required compact design with improved coil sensitivity. In this study, we applied a multitransceiver RF coil design to develop a DT proton/sodium coil for knee cartilage imaging at 3 T. With the new design, the size of the coil was minimized, and a high signal-to-noise ratio (SNR) was achieved. DT coil exhibited high levels of reflection S11 (∼-21 dB) and transmission coefficient S12 (∼-19 dB) for both the proton and sodium coils. High SNR (range 27-38) and contrast-to-noise ratio (CNR) (range 15-21) were achieved in sodium MR imaging of knee cartilage in vivo at 3-mm(3) isotropic resolution. This DT coil performance was comparable to that measured using a sodium-only birdcage coil (SNR of 28 and CNR of 20). Clinical evaluation of the DT coil on four normal subjects demonstrated a consistent acquisition of high-resolution proton images and measurement of relative sodium concentrations of knee cartilages without repositioning of the subjects during the same MR scanning session. PMID:22297242

  11. An additive manufacturing-based PCL-alginate-chondrocyte bioprinted scaffold for cartilage tissue engineering.

    Science.gov (United States)

    Kundu, Joydip; Shim, Jin-Hyung; Jang, Jinah; Kim, Sung-Won; Cho, Dong-Woo

    2015-11-01

    Regenerative medicine is targeted to improve, restore or replace damaged tissues or organs using a combination of cells, materials and growth factors. Both tissue engineering and developmental biology currently deal with the process of tissue self-assembly and extracellular matrix (ECM) deposition. In this investigation, additive manufacturing (AM) with a multihead deposition system (MHDS) was used to fabricate three-dimensional (3D) cell-printed scaffolds using layer-by-layer (LBL) deposition of polycaprolactone (PCL) and chondrocyte cell-encapsulated alginate hydrogel. Appropriate cell dispensing conditions and optimum alginate concentrations for maintaining cell viability were determined. In vitro cell-based biochemical assays were performed to determine glycosaminoglycans (GAGs), DNA and total collagen contents from different PCL-alginate gel constructs. PCL-alginate gels containing transforming growth factor-β (TGFβ) showed higher ECM formation. The 3D cell-printed scaffolds of PCL-alginate gel were implanted in the dorsal subcutaneous spaces of female nude mice. Histochemical [Alcian blue and haematoxylin and eosin (H&E) staining] and immunohistochemical (type II collagen) analyses of the retrieved implants after 4 weeks revealed enhanced cartilage tissue and type II collagen fibril formation in the PCL-alginate gel (+TGFβ) hybrid scaffold. In conclusion, we present an innovative cell-printed scaffold for cartilage regeneration fabricated by an advanced bioprinting technology. PMID:23349081

  12. Chondroitin sulfate and glucosamine in the cartilage and subchondral bone repair of dogs - Histological findings

    Directory of Open Access Journals (Sweden)

    R.B. Eleotério

    2015-04-01

    Full Text Available Chondroitin and glucosamine sulfate nutraceuticals are commonly used in the management of degenerative articular disease in veterinary routine. However, there are controversies on the contribution of these substances to articular cartilage. The purpose of this study was to evaluate the efficiency of a chondroitin and glucosamine sulfate-based veterinary nutraceutical on the repair of an induced osteochondral defect in a dog femoral condyle, by macroscopic, histological and histomorphometric analyses. The nutraceutical was orally administered the day following injury induction, every 24 hours (treated group, TG, n=24, compared with animals that did not receive the product (control group, CG, n=24. Six animals per group were anaesthetized for sample collection at 15, 30, 60 and 90 days after surgery. At 15 days, defects were macroscopically filled with red-pinkish tissue. After 30 days, whitish color tissue was observed, both in TG and CG animals, with firmer consistency to touch at 60 and 90 postoperative days. Histological analysis demonstrated that, in both groups, there was initial blood clot formation, which was subsequently substituted by a fibrin net, with capillary proliferation from the adjacent bone marrow and infiltration of mesenchymal cells in clot periphery. As cellular differentiation developed, repair tissue presented a fibrocartilage aspect most of the time, and new subchondral bone formation occurred in the deepest area corresponding to the defect. Histomorphometry suggested that the nutraceutical did not favor the articular cartilage repair process. It was concluded that nutraceutical did not significantly influence chondrocytes proliferation or hyaline architecture restoration.

  13. An overview of multiphase cartilage mechanical modelling and its role in understanding function and pathology.

    Science.gov (United States)

    Klika, Václav; Gaffney, Eamonn A; Chen, Ying-Chun; Brown, Cameron P

    2016-09-01

    There is a long history of mathematical and computational modelling with the objective of understanding the mechanisms governing cartilage׳s remarkable mechanical performance. Nonetheless, despite sophisticated modelling development, simulations of cartilage have consistently lagged behind structural knowledge and thus the relationship between structure and function in cartilage is not fully understood. However, in the most recent generation of studies, there is an emerging confluence between our structural knowledge and the structure represented in cartilage modelling. This raises the prospect of further refinement in our understanding of cartilage function and also the initiation of an engineering-level understanding for how structural degradation and ageing relates to cartilage dysfunction and pathology, as well as informing the potential design of prospective interventions. Aimed at researchers entering the field of cartilage modelling, we thus review the basic principles of cartilage models, discussing the underlying physics and assumptions in relatively simple settings, whilst presenting the derivation of relatively parsimonious multiphase cartilage models consistent with our discussions. We proceed to consider modern developments that start aligning the structure captured in the models with observed complexities. This emphasises the challenges associated with constitutive relations, boundary conditions, parameter estimation and validation in cartilage modelling programmes. Consequently, we further detail how both experimental interrogations and modelling developments can be utilised to investigate and reduce such difficulties before summarising how cartilage modelling initiatives may improve our understanding of cartilage ageing, pathology and intervention. PMID:27195911

  14. ENDOSCOPIC TYMPANO PLASTY TEMPORALIS FASCIA VERSUS CARTILAGE : COMPARATIVE STUDY

    Directory of Open Access Journals (Sweden)

    Naveen Kumar

    2015-08-01

    Full Text Available OBJECTIVE: To compare the graft acceptance rates and auditory outcomes of endoscopic cartilage tympanoplasty operations with those of endoscopic primary tympanoplasty using temporalis fascia in a homogenous group of patients . MATERIAL AND METHODS : This prospective study was conducted on 64 patients between the ages of 15 to 50 years. All patients had a central tympanic membrane perforation without infection in middle ear or upper respiratory tract. RESULTS : Anatomical results in terms of graft uptake and intact tympanic membrane over a period of 2 years showed good results both in 26(92.85% cases in cartilage group and in 33(91.66% cases in temporalis fascia group. The average post - operative Air bone gap in endoscopic fascia tympanoplasty group was 14.61db and 15.65db in endoscopic cartilage tympanoplasty group . CONCLUSION: Endoscopic tympanoplasty is a minimally invasive, sutureless procedure with better patient compliance. Tympanoplasty with cartilage graft has a high degree of graft take up. Tympanoplasty with cartilage provides better results in terms of integrity and intactness of the graft and less percentage of postoperative discharge from the operated ear.

  15. Formative, Informative, and Summative Assessment: The Relationship among Curriculum-Based Measurement of Reading, Classroom Engagement, and Reading Performance

    Science.gov (United States)

    Marchand, Gwen C.; Furrer, Carrie J.

    2014-01-01

    This study explored the relationships among formative curriculum-based measures of reading (CBM-R), student engagement as an extra-academic indicator of student motivation, and summative performance on a high-stakes reading assessment. A diverse sample of third-, fourth-, and fifth-grade students and their teachers responded to questionnaires…

  16. The Star Formation History of Galaxies Measured from Individual Pixels. I. The Hubble Deep Field North

    CERN Document Server

    Conti, A; Hopkins, A M; Budavari, T; Szalay, A S; Csabai, I; Schmidt, S J; Adams, C; Petrovic, N D; Conti, Alberto; Connolly, Andrew J.; Hopkins, Andrew M.; Szalay, Alex S.; Csabai, Istvan; Schmidt, Samuel J.; Adams, Carla; Petrovic, Nada

    2003-01-01

    We analyze the photometric information contained in individual pixels of galaxies in the Hubble Deep Field North (HDFN) using a new technique, _pixel-z_, that combines predictions of evolutionary synthesis models with photometric redshift template fitting. Each spectral energy distribution template is a result of modeling of the detailed physical processes affecting gas properties and star formation efficiency. The criteria chosen to generate the SED templates is that of sampling a wide range of physical characteristics such as age, star formation rate, obscuration and metallicity. A key feature of our method is the sophisticated use of error analysis to generate error maps that define the reliability of the template fitting on pixel scales and allow for the separation of the interplay among dust, metallicity and star formation histories. This technique offers a number of advantages over traditional integrated color studies. As a first application, we derive the star formation and metallicity histories of gal...

  17. The measured compositions of Uranus and Neptune from their formation on the CO iceline

    OpenAIRE

    Ali-Dib, M.; Mousis, O.; Petit, J.-M.; Lunine, J. I.

    2014-01-01

    The formation mechanisms of the ice giants Uranus and Neptune, and the origin of their elemental and isotopic compositions, have long been debated. The density of solids in the outer protosolar nebula is too low to explain their formation, and spectroscopic observations show that both planets are highly enriched in carbon, very poor in nitrogen, and the ices from which they originally formed might had deuterium-to-hydrogen ratios lower than the predicted cometary value, unexplained properties...

  18. The effect of calcification on the structural mechanics of the costal cartilage.

    Science.gov (United States)

    Forman, Jason L; Kent, Richard W

    2014-01-01

    The costal cartilage often undergoes progressive calcification with age. This study sought to investigate the effects of calcification on the structural mechanics of whole costal cartilage segments. Models were developed for five costal cartilage specimens, including representations of the cartilage, the perichondrium, calcification, and segments of the rib and sternum. The material properties of the cartilage were determined through indentation testing; the properties of the perichondrium were determined through optimisation against structural experiments. The calcified regions were then expanded or shrunk to develop five different sensitivity analysis models for each. Increasing the relative volume of calcification from 0% to 24% of the cartilage volume increased the stiffness of the costal cartilage segments by a factor of 2.3-3.8. These results suggest that calcification may have a substantial effect on the stiffness of the costal cartilage which should be considered when modelling the chest, especially if age is a factor.

  19. Cartilage Grown in Lab Might One Day Help Younger Arthritis Sufferers

    Science.gov (United States)

    ... Cartilage Grown in Lab Might One Day Help Younger Arthritis Sufferers Made of patients' stem cells and ... eliminate the need for hip replacement surgery in younger arthritis patients. The cartilage hasn't been tested ...

  20. Cartilage Tissue Engineering: the effect of different biomaterials, cell types and culture methods

    NARCIS (Netherlands)

    W.J.C.M. Marijnissen (Willem)

    2006-01-01

    textabstractChapter 1 outlines the normal structure and composition of articular cartilage and the inefficient spontaneous healing response after focal damage. Current surgical treatment options are briefly discussed and tissue engineering techniques for the repair of articular cartilage defects

  1. Changes in articular cartilage after meniscectomy and meniscus replacement using a biodegradable porous polymer implant

    NARCIS (Netherlands)

    Hannink, G.J.; Tienen, T.G. van; Schouten, A.J.; Buma, P.

    2011-01-01

    PURPOSE: To evaluate the long-term effects of implantation of a biodegradable polymer meniscus implant on articular cartilage degeneration and compare this to articular cartilage degeneration after meniscectomy. METHODS: Porous polymer polycaprolacton-based polyurethane meniscus implants were implan

  2. An exploration of the ability of tepoxalin to ameliorate the degradation of articular cartilage in a canine in vitro model

    Directory of Open Access Journals (Sweden)

    Clegg Peter D

    2009-07-01

    Full Text Available Abstract Background To study the ability of tepoxalin, a dual inhibitor of cyclooxygenase (COX and lipoxygenase (LOX and its active metabolite to reduce the catabolic response of cartilage to cytokine stimulation in an in vitro model of canine osteoarthritis (OA. Grossly normal cartilage was collected post-mortem from seven dogs that had no evidence of joint disease. Cartilage explants were cultured in media containing the recombinant canine interleukin-1β (IL-1β at 100 ng/ml and recombinant human oncostatin-M (OSM at 50 ng/ml. The effects of tepoxalin and its metabolite were studied at three concentrations (1 × 10-5, 1 × 10-6 and 1 × 10-7 M. Total glycosaminoglycan (GAG and collagen (hydroxyproline release from cartilage explants were used as outcome measures of proteoglycan and collagen depletion respectively. PGE2 and LTB4 assays were performed to study the effects of the drug on COX and LOX activity. Results Treatment with IL-1β and OSM significantly upregulated both collagen (p = 0.004 and proteoglycan (p = 0.001 release from the explants. Tepoxalin at 10-5 M and 10-6 M caused a decrease in collagen release from the explants (p = 0.047 and p = 0.075. Drug treatment showed no effect on GAG release. PGE2 concentration in culture media at day 7 was significantly increased by IL-1β and OSM and treatment with both tepoxalin and its metabolite showed a trend towards dose-dependent reduction of PGE2 production. LTB4 concentrations were too low to be quantified. Cytotoxicity assays suggested that neither tepoxalin nor its metabolite had a toxic effect on the cartilage chondrocytes at the concentrations and used in this study. Conclusion This study provides evidence that tepoxalin exerts inhibition of COX and can reduce in vitro collagen loss from canine cartilage explants at a concentration of 10-5 M. We can conclude that, in this model, tepoxalin can partially inhibit the development of cartilage degeneration when it is available locally to

  3. Altered swelling and ion fluxes in articular cartilage as a biomarker in osteoarthritis and joint immobilization: a computational analysis

    Science.gov (United States)

    Manzano, Sara; Manzano, Raquel; Doblaré, Manuel; Doweidar, Mohamed Hamdy

    2015-01-01

    In healthy cartilage, mechano-electrochemical phenomena act together to maintain tissue homeostasis. Osteoarthritis (OA) and degenerative diseases disrupt this biological equilibrium by causing structural deterioration and subsequent dysfunction of the tissue. Swelling and ion flux alteration as well as abnormal ion distribution are proposed as primary indicators of tissue degradation. In this paper, we present an extension of a previous three-dimensional computational model of the cartilage behaviour developed by the authors to simulate the contribution of the main tissue components in its behaviour. The model considers the mechano-electrochemical events as concurrent phenomena in a three-dimensional environment. This model has been extended here to include the effect of repulsion of negative charges attached to proteoglycans. Moreover, we have studied the fluctuation of these charges owning to proteoglycan variations in healthy and pathological articular cartilage. In this sense, standard patterns of healthy and degraded tissue behaviour can be obtained which could be a helpful diagnostic tool. By introducing measured properties of unhealthy cartilage into the computational model, the severity of tissue degeneration can be predicted avoiding complex tissue extraction and subsequent in vitro analysis. In this work, the model has been applied to monitor and analyse cartilage behaviour at different stages of OA and in both short (four, six and eight weeks) and long-term (11 weeks) fully immobilized joints. Simulation results showed marked differences in the corresponding swelling phenomena, in outgoing cation fluxes and in cation distributions. Furthermore, long-term immobilized patients display similar swelling as well as fluxes and distribution of cations to patients in the early stages of OA, thus, preventive treatments are highly recommended to avoid tissue deterioration. PMID:25392400

  4. The Protective Effects of Salubrinal on the Cartilage and Subchondral Bone of the Temporomandibular Joint under Various Compressive Mechanical Stimulations.

    Science.gov (United States)

    Wen, Juan; Jiang, Yuanyuan; Zhang, Caixia; Chen, Sheng; Li, Huang

    2016-01-01

    Excessive mechanical loads on the temporomandibular joint (TMJ) can cause mandibular cartilage degradation and subchondral bone erosion, but the treatment of these conditions remains challenging. Salubrinal, which target eukaryotic translation initiation factor 2 alpha, has been shown to have multiple beneficial effects on skeletal tissue. Here, we examined the effect of a Salubrinal injection on the mandibular cartilage and subchondral bone of the TMJ under various compressive stresses. We conducted in vivo analyses in rat models using various compressive stresses (40 g and 80 g), and we observed time-related degeneration and pathological changes in the cartilage and subchondral bone of the TMJ at days 1, 3 and 7 through histological measurements, subcellular observation, and changes in proliferation and apoptosis. After the Salubrinal injection, the thickness of the cartilage recovered, and the pathological change was alleviated. In the Salubrinal/light (Sal/light) compressive stress group, the drug altered the proliferation and apoptosis of chondrocytes most significantly at day 1. In the Salubrinal/heavy (Sal/heavy) compressive stress group, the drug increased the proliferation of chondrocytes most significantly at day 1 and reduced the apoptosis of chondrocytes most significantly at day 7. Salubrinal also increased the area of the bone trabeculae and suppressed inflammatory responses and pathological change in the subchondral bone of the TMJ. Together, these results indicate that the administration of Salubrinal reduces apoptosis and strengthens the proliferation of chondrocyte to varying degrees at days 1, 3 and 7 under various compressive mechanical stresses, both of which contribute to the recovery of cartilage thickness and the alleviation of pathological change. Salubrinal also suppresses inflammatory responses and pathological change in the subchondral bone of the TMJ. PMID:27196267

  5. The Protective Effects of Salubrinal on the Cartilage and Subchondral Bone of the Temporomandibular Joint under Various Compressive Mechanical Stimulations.

    Directory of Open Access Journals (Sweden)

    Juan Wen

    Full Text Available Excessive mechanical loads on the temporomandibular joint (TMJ can cause mandibular cartilage degradation and subchondral bone erosion, but the treatment of these conditions remains challenging. Salubrinal, which target eukaryotic translation initiation factor 2 alpha, has been shown to have multiple beneficial effects on skeletal tissue. Here, we examined the effect of a Salubrinal injection on the mandibular cartilage and subchondral bone of the TMJ under various compressive stresses. We conducted in vivo analyses in rat models using various compressive stresses (40 g and 80 g, and we observed time-related degeneration and pathological changes in the cartilage and subchondral bone of the TMJ at days 1, 3 and 7 through histological measurements, subcellular observation, and changes in proliferation and apoptosis. After the Salubrinal injection, the thickness of the cartilage recovered, and the pathological change was alleviated. In the Salubrinal/light (Sal/light compressive stress group, the drug altered the proliferation and apoptosis of chondrocytes most significantly at day 1. In the Salubrinal/heavy (Sal/heavy compressive stress group, the drug increased the proliferation of chondrocytes most significantly at day 1 and reduced the apoptosis of chondrocytes most significantly at day 7. Salubrinal also increased the area of the bone trabeculae and suppressed inflammatory responses and pathological change in the subchondral bone of the TMJ. Together, these results indicate that the administration of Salubrinal reduces apoptosis and strengthens the proliferation of chondrocyte to varying degrees at days 1, 3 and 7 under various compressive mechanical stresses, both of which contribute to the recovery of cartilage thickness and the alleviation of pathological change. Salubrinal also suppresses inflammatory responses and pathological change in the subchondral bone of the TMJ.

  6. Cold Atmospheric Plasma Modified Electrospun Scaffolds with Embedded Microspheres for Improved Cartilage Regeneration

    OpenAIRE

    Wei Zhu; Castro, Nathan J.; Xiaoqian Cheng; Michael Keidar; Lijie Grace Zhang

    2015-01-01

    Articular cartilage is prone to degeneration and possesses extremely poor self-healing capacity due to inherent low cell density and the absence of a vasculature network. Tissue engineered cartilage scaffolds show promise for cartilage repair. However, there still remains a lack of ideal biomimetic tissue scaffolds which effectively stimulate cartilage regeneration with appropriate functional properties. Therefore, the objective of this study is to develop a novel biomimetic and bioactive ele...

  7. Reconstruction of focal cartilage defects in the talus with miniarthrotomy and collagen matrix

    OpenAIRE

    Walther, M.; Altenberger, S; Kriegelstein, S; Volkering, C; Röser, A.

    2014-01-01

    Surgical principal and objective Treatment of focal cartilage defects (traumatic or osteochondrosis dissecans) of the talus using a collagen matrix. The goal is to stabilize the superclot formed after microfracturing to accommodate cartilage repair. The procedure can be carried out via miniarthrotomy, without medial malleolus osteotomy. Indications International Cartilage Repair Society (ICRS) grade III and IV focal cartilage defects of the talus > 1.5 cm2. Contraindications Generalized osteo...

  8. Enhanced regulatory gene expressions in the blood and articular cartilage of patients with rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Elena Vasilyevna Chetina

    2012-01-01

    Full Text Available Objective: to study the expression ratio of the non-tissue specific regulatory genes mTOR, р21, ATG1, caspase 3, tumor necrosis factor-а (TNF-а, and interleukin-6 (IL-6, as well as matrix metalloproteinase 13 (MMP-13 and X type collagen (COL10A1, cartilage resorption-associated MMP13 and COL10A1 in the blood and knee articular cartilage in patients with rheumatoid arthritis (RA. Subjects and methods. Twenty-five specimens of the distal femoral articular cartilage condyles were studied in 15 RA patients (mean age 52.4+9.1 years after endoprosthetic knee joint replacement and in 10 healthy individuals (mean age 36.0+9.1 years included into the control group. Twenty-eight blood samples taken from 28 RA patients (aged 52+7.6 years prior to endoprosthetic knee joint replacement and 27 blood samples from healthy individuals (mean age 53.6+8.3 years; a control group were also analyzed. Real-time quantitative polymerase chain reaction was applied to estimate the expression of the mTOR, p21, ATG1, caspase 3, TNF-а, IL- 6, COL0A1, and MMP-13 genes. The levels of a protein equivalent in the p70-S6K(activated by mTOR, p21, and caspase 3 genes concerned was measured in the isolated lymphocyte lysates, by applying the commercially available ELISA kits. Total protein in the cell extracts was determined using the Bradford assay procedure. Results. The cartilage samples from patients with end-stage RA exhibited a significantly higher mTOR, ATG1, p21, TNFа, MMP-13, and COL10A1 gene expressions than did those from the healthy individuals. At the same time, IL6 gene expression was much lower than that in the control group. The expressions of the mTOR, ATG1, p21, TNFа, and IL 6 genes in the blood of RA patients were much greater than those in the donors. Caspase 3 expression did not differ essentially in the bloods of the patients with RA and healthy individuals. The bloods failed to show MMP-13 and COL10A1 expressions. High mTOR and p21 gene expressions were

  9. Wnt/β-catenin signaling of cartilage canal and osteochondral junction chondrocytes and full thickness cartilage in early equine osteochondrosis.

    Science.gov (United States)

    Kinsley, Marc A; Semevolos, Stacy A; Duesterdieck-Zellmer, Katja F

    2015-10-01

    The objective of this study was to elucidate gene and protein expression of Wnt signaling molecules in chondrocytes of foals having early osteochondrosis (OC) versus normal controls. The hypothesis was that increased expression of components of Wnt signaling pathway in osteochondral junction (OCJ) and cartilage canal (CC) chondrocytes would be found in early OC when compared to controls. Paraffin-embedded osteochondral samples (7 OC, 8 normal) and cDNA from whole cartilage (7 OC, 10 normal) and chondrocytes surrounding cartilage canals and osteochondral junctions captured with laser capture microdissection (4 OC, 6 normal) were obtained from femoropatellar joints of 17 immature horses. Equine-specific Wnt signaling molecule mRNA expression levels were evaluated by two-step real-time qPCR. Spatial tissue protein expression of β-catenin, Wnt-11, Wnt-4, and Dkk-1 was determined by immunohistochemistry. There was significantly decreased Wnt-11 and increased β-catenin, Wnt-5b, Dkk-1, Lrp6, Wif-1, Axin1, and SC-PEP gene expression in early OC cartilage canal chondrocytes compared to controls. There was also significantly increased β-catenin gene expression in early OC osteochondral junction chondrocytes compared to controls. Based on this study, abundant gene expression differences in OC chondrocytes surrounding cartilage canals suggest pathways associated with catabolism and inhibition of chondrocyte maturation are targeted in early OC pathogenesis. PMID:25676127

  10. The Bursty Star Formation Histories of Low-mass Galaxies at $0.4Formation Rates Measured from FUV and H$\\beta$

    CERN Document Server

    Guo, Yicheng; Faber, S M; Koo, David C; Krumholz, Mark R; Trump, Jonathan R; Willner, S P; Amorín, Ricardo; Barro, Guillermo; Bell, Eric F; Gardner, Jonathan P; Gawiser, Eric; Hathi, Nimish P; Koekemoer, Anton M; Pacifici, Camilla; Pérez-González, Pablo G; Ravindranath, Swara; Reddy, Naveen; Teplitz, Harry I; Yesuf, Hassen

    2016-01-01

    We investigate the burstiness of star formation histories (SFHs) of galaxies at $0.4formation rates (SFRs) measured from FUV (1500 \\AA) and H$\\beta$ (FUV--to--H$\\beta$ ratio). Our sample contains 164 galaxies down to stellar mass (M*) of $10^{8.5} M_\\odot$ in the CANDELS GOODS-N region, where TKRS Keck/DEIMOS spectroscopy and HST/WFC3 F275W images from CANDELS and HDUV are available. When the ratio of FUV- and H$\\beta$-derived SFRs is measured, dust extinction correction is negligible (except for very dusty galaxies) with the Calzetti attenuation curve. The FUV--to--H$\\beta$ ratio of our sample increases with the decrease of M* and SFR. The median ratio is $\\sim$1 at M* $\\sim 10^{10} M_\\odot$ (or SFR = 20 $M_\\odot$/yr) and increases to $\\sim$1.6 at M* $\\sim 10^{8.5} M_\\odot$ (or SFR $\\sim 0.5 M_\\odot$/yr). At M* $< 10^{9.5} M_\\odot$, our median FUV--to--H$\\beta$ ratio is higher than that of local galaxies at the same M*, implying a redshift evolution. Bursty SFH on a ...

  11. Cartilage oligomeric matrix protein enhances the vascularization of acellular nerves

    Directory of Open Access Journals (Sweden)

    Wei-ling Cui

    2016-01-01

    Full Text Available Vascularization of acellular nerves has been shown to contribute to nerve bridging. In this study, we used a 10-mm sciatic nerve defect model in rats to determine whether cartilage oligomeric matrix protein enhances the vascularization of injured acellular nerves. The rat nerve defects were treated with acellular nerve grafting (control group alone or acellular nerve grafting combined with intraperitoneal injection of cartilage oligomeric matrix protein (experimental group. As shown through two-dimensional imaging, the vessels began to invade into the acellular nerve graft from both anastomotic ends at day 7 post-operation, and gradually covered the entire graft at day 21. The vascular density, vascular area, and the velocity of revascularization in the experimental group were all higher than those in the control group. These results indicate that cartilage oligomeric matrix protein enhances the vascularization of acellular nerves.

  12. Gene Transfer Strategies to Promote Chondrogenesis and Cartilage Regeneration.

    Science.gov (United States)

    Im, Gun-Il

    2016-04-01

    Gene transfer has been used experimentally to promote chondrogenesis and cartilage regeneration. While it is controversial to apply gene therapy for nonlethal conditions such as cartilage defect, there is a possibility that the transfer of therapeutic transgenes may dramatically increase the effectiveness of cell therapy and reduce the quantity of cells that are needed to regenerate cartilage. Single or combination of growth factors and transcription factors has been transferred to mesenchymal stem cells or articular chondrocytes using both nonviral and viral approaches. The current challenge for the clinical applications of genetically modified cells is ensuring the safety of gene therapy while guaranteeing effectiveness. Viral gene delivery methods have been mainstays currently with enhanced safety features being recently refined. On the other hand, efficiency has been greatly improved in nonviral delivery. This review summarizes the history and recent update on the gene transfer to enhance chondrogenesis from stem cells or articular chondrocytes.

  13. Cartilage oligomeric matrix protein specific antibodies are pathogenic

    DEFF Research Database (Denmark)

    Geng, Hui; Nandakumar, Kutty Selva; Pramhed, Anna;

    2012-01-01

    ABSTRACT: INTRODUCTION: Cartilage oligomeric matrix protein (COMP) is a major non-collagenous component of cartilage. Earlier, we developed a new mouse model for rheumatoid arthritis using COMP. This study was undertaken to investigate the epitope specificity and immunopathogenicity of COMP...... and the pathogenicity of mAbs was investigated by passive transfer experiments. RESULTS: B cell immunodominant epitopes were localized within 4 antigenic domains of the COMP but with preferential response to the epidermal growth factor (EGF)-like domain. Some of our anti-COMP mAbs showed interactions with the native...... form of COMP, which is present in cartilage and synovium. Passive transfer of COMP-specific mAbs enhanced arthritis when co-administrated with a sub-arthritogenic dose of a mAb specific to collagen type II. Interestingly, we found that a combination of 5 COMP mAbs was capable of inducing arthritis...

  14. [Structure of the articular cartilage in the middle aged].

    Science.gov (United States)

    Kop'eva, T N; Mul'diiarov, P Ia; Bel'skaia, O B; Pastel', V B

    1983-10-01

    In persons 17-83 years of age having no articular disorders 39 samples of the patellar articular cartilage, the articulated surface and the femoral head have been studied histochemically, histometrically and electron microscopically. Age involution of the articular cartilage is revealed after 40 years of age as a progressive decrease in chondrocytes density in the superficial and (to a less degree) in the intermediate zones. This is accompanied with a decreasing number of 3- and 4-cellular lacunae and with an increasing number of unicellular and hollow lacunae. In some chondrocytes certain distrophic and necrotic changes are revealed. In the articular matrix the zone with the minimal content of glycosaminoglycans becomes thicker and keratansulfate content in the territorial matrix of the cartilage deep zone grows large.

  15. Evaluation of Automated Volumetric Cartilage Quantification for Hip Preservation Surgery.

    Science.gov (United States)

    Ramme, Austin J; Guss, Michael S; Vira, Shaleen; Vigdorchik, Jonathan M; Newe, Axel; Raithel, Esther; Chang, Gregory

    2016-01-01

    Automating the process of femoroacetabular cartilage identification from magnetic resonance imaging (MRI) images has important implications to guiding clinical care by providing a temporal metric that allows for optimizing the timing for joint preservation surgery. In this paper, we evaluate a new automated cartilage segmentation method using a time trial, segmented volume comparison, overlap metrics, and Euclidean distance mapping. We report interrater overlap metrics using the true fast imaging with steady-state precession MRI sequence of 0.874, 0.546, and 0.704 for the total overlap, union overlap, and mean overlap, respectively. This method was 3.28× faster than manual segmentation. This technique provides clinicians with volumetric cartilage information that is useful for optimizing the timing for joint preservation procedures. PMID:26377376

  16. Gene Transfer Strategies to Promote Chondrogenesis and Cartilage Regeneration.

    Science.gov (United States)

    Im, Gun-Il

    2016-04-01

    Gene transfer has been used experimentally to promote chondrogenesis and cartilage regeneration. While it is controversial to apply gene therapy for nonlethal conditions such as cartilage defect, there is a possibility that the transfer of therapeutic transgenes may dramatically increase the effectiveness of cell therapy and reduce the quantity of cells that are needed to regenerate cartilage. Single or combination of growth factors and transcription factors has been transferred to mesenchymal stem cells or articular chondrocytes using both nonviral and viral approaches. The current challenge for the clinical applications of genetically modified cells is ensuring the safety of gene therapy while guaranteeing effectiveness. Viral gene delivery methods have been mainstays currently with enhanced safety features being recently refined. On the other hand, efficiency has been greatly improved in nonviral delivery. This review summarizes the history and recent update on the gene transfer to enhance chondrogenesis from stem cells or articular chondrocytes. PMID:26414246

  17. Reconstruction of traumatic orbital floor defects using irradiated cartilage homografts.

    Science.gov (United States)

    Bevivino, J R; Nguyen, P N; Yen, L J

    1994-07-01

    The important role of orbital shape and volume reconstruction has been studied by many investigators. There is, however, no consensus on the material that should be used in the reconstruction of the orbit. Both biologic and alloplastic materials have been used, each with its advantages and disadvantages. Here we report our experience with irradiated costal cartilage homograft in the reconstruction of the orbital floor. Irradiated cartilage grafts were used in 31 patients with significant traumatic defects in the orbital floor. Long-term follow-up in 21 patients up to 48 months revealed no incidence of graft infections, extrusions, or clinically detectable graft distortion or resorption. Irradiated cartilage homograft appears to be an excellent material for reconstruction of the orbital floor. PMID:7944194

  18. On the roles and regulation of chondroitin sulfate and heparan sulfate in zebrafish pharyngeal cartilage morphogenesis

    DEFF Research Database (Denmark)

    Holmborn, Katarina; Habicher, Judith; Kasza, Zsolt;

    2012-01-01

    The present study addresses the roles of heparan sulfate (HS) proteoglycans and chondroitin sulfate (CS) proteoglycans in the development of zebrafish pharyngeal cartilage structures. uxs1 and b3gat3 mutants, predicted to have impaired biosynthesis of both HS and CS because of defective formation...... of the common proteoglycan linkage tetrasaccharide were analyzed along with ext2 and extl3 mutants, predicted to have defective HS polymerization. Notably, the effects on HS and CS biosynthesis in the respective mutant strains were shown to differ from what had been hypothesized. In uxs1 and b3gat3 mutant...... in the single mutant strains, as well as in ext2;uxs1 double mutants, was conducted. A correlation between HS and CS production and phenotypes was found, such that impaired HS biosynthesis was shown to affect chondrocyte intercalation, whereas impaired CS biosynthesis inhibited formation of the extracellular...

  19. Magnetic Resonance Imaging of Cartilage Contact and Bound Water in ACL-Deficient and ACL Reconstructed Knees

    Science.gov (United States)

    Baer, Geoffrey Scott; Kaiser, Jarred; Vignos, Michael; Liu, Fang; Smith, Colin Robert; Kijowski, Richard; Thelen, Darryl

    2016-01-01

    Objectives: Osteoarthritis (OA) is common following ACL-reconstructive (ACLR) surgery (6). The cause of early OA is not understood, but theories have focused on osteochondral damage at the time of injury (2) and abnormal joint mechanics following surgical repair (7). In this study, we investigate the inter-relationship of cartilage mechanics and biomarkers of OA in both ACL-deficient (ACLD) and ACLR knees. Our approach employs a novel dynamic MR sequence to measure joint mechanics (3) and the recently developed mcDESPOT to assess regional variations in water bound to proteoglycan (PG) (5). We hypothesize that bound water will be diminished in the cartilage of ACLD knees and, after surgery, will continue to adapt in a manner that reflects altered cartilage loading. This abstract presents initial observations on a cross-section of healthy, ACLD and ACLR knees. Methods: The dominant knees of 8 healthy controls, ACLD knees of 5 patients and ACLR knees of 8 patients were imaged in a 3 T MRI scanner (Table). Controls had no history of pain, injury, or surgery to their knee. Patients had no additional ligament injury and no meniscal damage. ACLD subjects were imaged prior to reconstructive surgery. Femoral and tibial cartilage were segmented from MR images and cartilage thickness was calculated. The mcDESPOT sequence provided a fraction map of water bound to PG (Fpg). Subjects flexed their knee against an inertial load at 0.5 Hz, while a SPGR-VIPR sequence continuously acquired volumetric data. Kinematics were obtained using model tracking of the dynamic images (3). Cartilage was registered to the bone segments for all frames, and contact patterns were characterized by the proximity between surfaces. Spatial representations of tibial cartilage contact, thickness and Fpg were co-registered for each subject. Results: Our initial images suggest lower Fpg values in ACLD knees, primarily on the posterior-lateral tibia. This is also observed in ACLR knees, with additional

  20. Direct measurement of particle formation and growth from the oxidation of biogenic emissions

    Directory of Open Access Journals (Sweden)

    T. M. VanReken

    2006-01-01

    Full Text Available A new facility has been developed to investigate the formation of new particles from the oxidation of volatile organic compounds emitted from vegetation. The facility consists of a biogenic emissions enclosure, an aerosol growth chamber, and the associated instrumentation. Using the facility, new particle formation events have been induced through the reaction of ozone with three different precursor gas mixtures: an α-pinene test mixture and the emissions of a Holm oak (Quercus ilex specimen and a loblolly pine (Pinus taeda specimen. The results demonstrate the variability between species in their potential to form new aerosol products. The emissions of Q. ilex specimen resulted in fewer particles than did α-pinene, although the concentration of monoterpenes was roughly equal in both experiments before the addition of ozone. Conversely, the oxidation of P. taeda specimen emissions led to the formation of more particles than either of the other two gas mixtures, despite a lower initial terpenoid concentration. These variations can be attributed to differences in the speciation of the vegetative emissions with respect to the α-pinene mixture and to each other. Specifically, the presence of β-pinene and other slower-reacting monoterpenes probably inhibited particle formation in the Q. ilex experiment, while the presence of sesquiterpenes, including β-caryophyllene, in the emissions of the P. taeda specimen were the likely cause of the more intense particle formation events observed during that experiment.

  1. Depth profiles for hydrogen-enhanced thermal donor formation in silicon: Spreading resistance probe measurements

    International Nuclear Information System (INIS)

    Hydrogen enhancement of formation rates for oxygen-related thermal donors in Si has been investigated for dependence on: the source of hydrogen, hydrogen isotope, and exposure time and temperature. Hydrogen injection efficiency is an important variable and depth profiles are dependent upon the surface preparation of samples exposed in an electron cyclotron resonance plasma where ion energies are ≤35 eV. Formation rates up to 2 x 1016 cm-3 at 400 C have been observed. A sublinear dependence of the donor formation rate on beam current under 50 keV ion implantation is interpreted as a competition between oxygen-hydrogen and hydrogen-hydrogen interactions. Dependence on isotope mass and on exposure time in the plasma indicates hydrogen is the diffusing species that determines the penetration depth for the enhanced donor formation. Peculiar box-like depth profiles and high formation rates near the advancing front produced in RF plasma exposures are suggestive of hydrogen accumulation near the advancing front. The temperature dependence for the penetration depth gives in activation energy of 1.5 ± 0.2 eV. This energy is attributed to trap-limited diffusion wherein hydrogen lowers the energy barrier for the oxygen motion necessary to form thermal donors

  2. Measurement of ethanol formation in single living cells of Chlamydomonas reinhardtii using synchrotron Fourier Transform Infrared spectromicroscopy

    Science.gov (United States)

    Goff, Kira L.; Quaroni, Luca; Pedersen, Tor; Wilson, Kenneth E.

    2010-02-01

    We demonstrate the capability of Fourier-Transform Infra-Red (FITR) spectroscopy to detect metabolite formation by the unicellular algae Chlamydomonas reinhardtii in solution. We show that using a synchrotron source in the microscopy configuration provides a sufficient s/n ratio to detect small molecular species accumulating at a single cell, allowing an increased sensitivity relative to measurements of bulk cultures. The formation of small molecular species, including ethanol and at least one carbonyl containing compound, can be detected with a time resolution of the order of one minute.

  3. Measurement of ethanol formation in single living cells of Chlamydomonas reinhardtii using synchrotron Fourier Transform Infrared spectromicroscopy

    International Nuclear Information System (INIS)

    We demonstrate the capability of Fourier-Transform Infra-Red (FITR) spectroscopy to detect metabolite formation by the unicellular algae Chlamydomonas reinhardtii in solution. We show that using a synchrotron source in the microscopy configuration provides a sufficient s/n ratio to detect small molecular species accumulating at a single cell, allowing an increased sensitivity relative to measurements of bulk cultures. The formation of small molecular species, including ethanol and at least one carbonyl containing compound, can be detected with a time resolution of the order of one minute.

  4. Inter -and intraobserver variation of ultrasonographic cartilage thickness assessments in small and large joints in healthy children

    Directory of Open Access Journals (Sweden)

    Stenbøg Elisabeth

    2009-06-01

    Full Text Available Abstract Background There is an increasing interest among pediatric rheumatologist for using ultrasonography (US in the daily clinical examination of children with juvenile idiopathic arthritis (JIA. Loss of joint cartilage may be an early feature of destructive disease in JIA. However, US still needs validation before it can be used as a diagnostic bedside tool in a pediatric setting. This study aims to assess the inter- and intraobserver reliability of US measurements of cartilage thickness in the joints of healthy children. Methods 740 joints of 74 healthy Caucasian children (27 girls/47 boys, aged 11.3 (7.11 – 16 years were examined with bilateral US in 5 preselected joints to assess the interobserver variability. In 17 of these children (6 girls/11 boys, aged 10.1(7.11–11.1 years, 170 joints was examined in an intraobserver sub study, with a 2 week interval between the first and second examination. Results In this study we found a good inter- and intraobserver agreement expressed as a coefficient of variation (CV less than 10% in the knee (CV = 9.5%interobserver and 5.9%intraobservserI, 9.3%intraobserverII respectively for the two intraobserver measurements and fairly good for the MCP joints (CV = 11.9%interobserver, 12.9%intraobserverI and 11.9%intraobsevrerII. In the ankle and PIP joints the inter- and intraobserver agreement was within an acceptable limit (CV26%. We found no difference in cartilage thickness between the left and right extremity in the investigated joints. Conclusion We found a good inter -and intraobserver agreement when measuring cartilage thickness with US. The inter- and intraobserver variation seemed not to be related to joint size. These findings suggest that positioning of the joint and the transducer is of major importance for reproducible US measurements. We found no difference in joint cartilage thickness between the left and right extremity in any of the examined joint of the healthy children. This is an

  5. Contribution of collagen network features to functional properties of engineered cartilage

    NARCIS (Netherlands)

    Bastiaansen-Jenniskens, Y.M.; Koevoet, W.; Bart, A.C.W. de; Linden, J.C. van der; Zuurmond, A.M.; Weinans, H.; Verhaar, J.A.N.; Osch, G.J.V.M. van; Groot, J. de

    2008-01-01

    Background: Damage to articular cartilage is one of the features of osteoarthritis (OA). Cartilage damage is characterised by a net loss of collagen and proteoglycans. The collagen network is considered highly important for cartilage function but little is known about processes that control composit

  6. Lubricin is expressed in chondrocytes derived from osteoarthritic cartilage encapsulated in poly (ethylene glycol) diacrylate scaffold.

    Science.gov (United States)

    Musumeci, G; Loreto, C; Carnazza, M L; Coppolino, F; Cardile, V; Leonardi, R

    2011-01-01

    Osteoarthritis (OA) is characterized by degenerative changes within joints that involved quantitative and/or qualitative alterations of cartilage and synovial fluid lubricin, a mucinous glycoprotein secreted by synovial fibroblasts and chondrocytes. Modern therapeutic methods, including tissue-engineering techniques, have been used to treat mechanical damage of the articular cartilage but to date there is no specific and effective treatment. This study aimed at investigating lubricin immunohistochemical expression in cartilage explant from normal and OA patients and in cartilage constructions formed by Poly (ethylene glycol) (PEG) based hydrogels (PEG-DA) encapsulated OA chondrocytes. The expression levels of lubricin were studied by immunohistochemistry: i) in tissue explanted from OA and normal human cartilage; ii) in chondrocytes encapsulated in hydrogel PEGDA from OA and normal human cartilage. Moreover, immunocytochemical and western blot analysis were performed in monolayer cells from OA and normal cartilage. The results showed an increased expression of lubricin in explanted tissue and in monolayer cells from normal cartilage, and a decreased expression of lubricin in OA cartilage. The chondrocytes from OA cartilage after 5 weeks of culture in hydrogels (PEGDA) showed an increased expression of lubricin compared with the control cartilage. The present study demonstrated that OA chondrocytes encapsulated in PEGDA, grown in the scaffold and were able to restore lubricin biosynthesis. Thus our results suggest the possibility of applying autologous cell transplantation in conjunction with scaffold materials for repairing cartilage lesions in patients with OA to reduce at least the progression of the disease.

  7. Relative contribution of matrix metalloprotease and cysteine protease activities to cytokine-stimulated articular cartilage degradation

    DEFF Research Database (Denmark)

    Sondergaard, B C; Henriksen, K; Wulf, H;

    2006-01-01

    OBJECTIVE: Both matrix metalloprotease (MMP) activity and cathepsin K (CK) activity have been implicated in cartilage turnover. We investigated the relative contribution of MMP activity and CK activity in cartilage degradation using ex vivo and in vivo models. METHODS: Bovine articular cartilage...

  8. Time-resolved measurement of single pulse femtosecond laser-induced periodic surface structure formation

    CERN Document Server

    Kafka, K R P; Li, H; Yi, A; Cheng, J; Chowdhury, E A

    2015-01-01

    Time-resolved diffraction microscopy technique has been used to observe the formation of laser-induced periodic surface structures (LIPSS) from the interaction of a single femtosecond laser pulse (pump) with a nano-scale groove mechanically formed on a single-crystal Cu substrate. The interaction dynamics (0-1200 ps) was captured by diffracting a time-delayed, frequency-doubled pulse from nascent LIPSS formation induced by the pump with an infinity-conjugate microscopy setup. The LIPSS ripples are observed to form sequentially outward from the groove edge, with the first one forming after 50 ps. A 1-D analytical model of electron heating and surface plasmon polariton (SPP) excitation induced by the interaction of incoming laser pulse with the groove edge qualitatively explains the time-evloution of LIPSS formation.

  9. Methane Hydrate Formation and Dissocation in a Partially Saturated Sand--Measurements and Observations

    Energy Technology Data Exchange (ETDEWEB)

    Kneafsey, Timothy J.; Tomutsa, Liviu; Moridis, George J.; Seol, Yongkoo; Freifeld, Barry; Taylor, Charles E.; Gupta, Arvind

    2005-03-01

    We performed a sequence of tests on a partially water-saturated sand sample contained in an x-ray transparent aluminum pressure vessel that is conducive to x-ray computed tomography (CT) observation. These tests were performed to gather data for estimation of thermal properties of the sand/water/gas system and the sand/hydrate/water/gas systems, as well as data to evaluate the kinetic nature of hydrate dissociation. The tests included mild thermal perturbations for the estimation of the thermal properties of the sand/water/gas system, hydrate formation, thermal perturbations with hydrate in the stability zone, hydrate dissociation through thermal stimulation, additional hydrate formation, and hydrate dissociation through depressurization with thermal stimulation. Density changes throughout the sample were observed as a result of hydrate formation and dissociation, and these processes induced capillary pressure changes that altered local water saturation.

  10. Nanopolymers Delivery of the Bone Morphogenetic Protein-4 Plasmid to Mesenchymal Stem Cells Promotes Articular Cartilage Repair In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Junjun Shi

    2012-01-01

    Full Text Available The clinical application of viral vectors for gene therapy is limited for biosafety consideration. In this study, to promote articular cartilage repair, poly (lactic-co glycolic acid (PLGA nanopolymers were used as non-viral vectors to transfect rabbit mesenchymal stem cells (MSCs with the pDC316-BMP4-EGFP plasmid. The cytotoxicity and transfection efficiency in vitro were acceptable measuring by CCK-8 and flow cytometry. After transfection, Chondrogenic markers (mRNA of Col2a1, Sox9, Bmp4, and Agg of experimental cells (MSCs being transfected with BMP-4 plasmid by PLGA nanopolymers were increased more than those of control cells (MSCs being transfected with naked BMP-4 plasmid alone. In vivo study, twelve rabbits (24 knees with large full thickness articular cartilage defects were randomly divided into the experimental group (MSCs being transfected with BMP-4 plasmid by PLGA nanopolymers and the control group (MSCs being transfected with naked BMP-4 plasmid. The experimental group showed better regeneration than the control group 6 and 12 weeks postoperatively. Hyaline-like cartilage formed at week 12 in the experimental group, indicating the local delivery of BMP-4 plasmid to MSCs by PLGA nanopolymers improved articular cartilage repair significantly. PLGA nanopolymers could be a promising and effective non-viral vector for gene therapy in cartilage repair.

  11. Metabolism of Cartilage Proteoglycans in Health and Disease

    Directory of Open Access Journals (Sweden)

    Demitrios H. Vynios

    2014-01-01

    Full Text Available Cartilage proteoglycans are extracellular macromolecules with complex structure, composed of a core protein onto which a variable number of glycosaminoglycan chains are attached. Their biosynthesis at the glycosaminoglycan level involves a great number of sugar transferases well-orchestrated in Golgi apparatus. Similarly, their degradation, either extracellular or intracellular in lysosomes, involves a large number of hydrolases. A deficiency or malfunction of any of the enzymes participating in cartilage proteoglycan metabolism may lead to severe disease state. This review summarizes the findings regarding this topic.

  12. Magnetic resonance imaging of hip joint cartilage and labrum

    Directory of Open Access Journals (Sweden)

    Christoph Zilkens

    2011-09-01

    Full Text Available Hip joint instability and impingement are the most common biomechanical risk factors that put the hip joint at risk to develop premature osteoarthritis. Several surgical procedures like periacetabular osteotomy for hip dysplasia or hip arthroscopy or safe surgical hip dislocation for femoroacetabular impingement aim at restoring the hip anatomy. However, the success of joint preserving surgical procedures is limited by the amount of pre-existing cartilage damage. Biochemically sensitive MRI techniques like delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC might help to monitor the effect of surgical or non-surgical procedures in the effort to halt or even reverse joint damage.

  13. Small-angle neutron scattering measurements of deuteride (hydride) formation and decomposition in single-crystal Pd

    International Nuclear Information System (INIS)

    The deuteride (hydride) precipitation and decomposition microstructure in single-crystal Pd has been investigated in a series of in situ small-angle neutron scattering (SANS) measurements. The particle morphology along the absorption and desorption branches of the 353-K pressure-composition isotherm are consistent with a loss of particle coherency, leading to the formation of large, micron-thick plates. The loss of coherency coincides with the system entering the miscibility gap, an observation that suggests irreversible dislocation formation in part drives the hysteretic behavior of the Pd-D (-H) system. SANS analysis further indicates that the decomposition process is characterized by a much higher particle dispersion, with a factor of 40 greater surface-to-volume ratio of the precipitating phase. This we attribute to a more heterogeneous transformation process, presumably at dislocations formed during initial deuteride formation

  14. Free Energies of Formation Measurements on Solid-State Electrochemical Cells

    Science.gov (United States)

    Rollino, J. A.; Aronson, S.

    1972-01-01

    A simple experiment is proposed that can provide the student with some insight into the chemical properties of solids. It also demonstrates the relationship between the Gibbs free energy of formation of an ionic solid and the emf of an electrochemical cell. (DF)

  15. Reliability of cut mark analysis in human costal cartilage: the effects of blade penetration angle and intra- and inter-individual differences.

    Science.gov (United States)

    Puentes, K; Cardoso, H F V

    2013-09-10

    Identification of tool class characteristics from cut marks in either bone or cartilage is a valuable source of data for the forensic scientist. Various animal models have been used in experimental studies for the analysis of individual and class characteristics. However, human tissue has seldom been used and it is likely to differ from that of non-humans in key aspects. This study wishes to assess how the knife's blade angle, and both intra- and inter-individual variation in cartilage samples affect the ability of costal cartilage to retain the original class characteristics of the knife, as measured microscopically by the distance between consecutive striations. The 120 cartilaginous samples used in this study originated from the ribcage of 6 male cadavers which were submitted to autopsy at the North Branch of the National Institute of Legal Medicine, in Portugal. Three different serrated knives were purchased from a large department store, and were used in the experimental cuts. Samples of costal cartilage from 2 individuals were assigned to each knife. Each individual provided 20 cartilage samples. Cartilage samples were manually cut using each of the three knives, following two motions: one straight up-and-down cutting motion and parallel and one perpendicular to the blade's teeth long axis forward cutting motion. Casts of the samples were made with Mikrosil(®). Image capture and processing were performed with an Olympus stereomicroscope and its software. The blade's penetration angle and inter-individual variation were shown to affect the identification of the tool class characteristics from the striation pattern observed in a kerf wall, although this seems to be related only to the degree of calcification of the costal cartilage. Intra-individual variation does not seem to significantly affect the identification of the tool class characteristics from the striation pattern observed in a kerf wall, for the same knife following the same motion. Although this