Sample records for graft model autograft

  1. Production of functional sperm by subcutaneous auto-grafting of immature testes in rainbow trout.

    PubMed

    Hayashi, Makoto; Sakuma, Daika; Yoshizaki, Goro

    2018-02-01

    Sexually mature individuals are indispensable for breeding programs. Salmonids require a long period before reaching sexual maturity, so we aimed to shorten the period required to obtain functional sperm by grafting immature testicular fragments into mature recipients, which we predicted would allow the grafted testicular fragments to skip the long pre-pubertal period. First, we demonstrated successful subcutaneous auto-grafting of testicular fragments in rainbow trout. Unilateral testectomy was performed, and the isolated immature testicular fragment was auto-grafted into the subcutaneous space along the back of recipient fish. The grafted testicular fragments developed synchronously with the recipients' testis remaining in its body cavity, and both eventually produced functional sperm. Next, immature testicular fragments were auto-grafted into the subcutaneous space of sexually mature males. We achieved this, without immune rejection, by isolating and cryopreserving testes from immature fish, and rearing these unilaterally testectomized fish until sexual maturity. The cryopreserved testes were then auto-grafted into the original, now spermiating fish. The grated immature testicular fragments differentiated and produced functional sperm within 5 months after grafting. By combining this grafting method with a technique to avoid immune rejection, we expect to develop a practical method for producing sperm in a shorter period in salmonids. © 2017 Wiley Periodicals, Inc.

  2. Failure Rate and Clinical Outcomes of Anterior Cruciate Ligament Reconstruction Using Autograft Hamstring Versus a Hybrid Graft.

    PubMed

    Leo, Brian M; Krill, Michael; Barksdale, Leticia; Alvarez-Pinzon, Andres M

    2016-11-01

    To compare the revision rate and subjective outcome measures of autograft hamstring versus a soft tissue hybrid graft combining both autograft hamstring and tibialis allograft for isolated anterior cruciate ligament (ACL) reconstruction. A single-center retrospective, nonrandomized, comparative study of isolated ACL reconstruction revision rates for subjects who underwent arthroscopic reconstruction of the ACL using autograft hamstring or a soft tissue hybrid graft using both autograft hamstring and tibialis allograft was performed. Patients with isolated ACL tears were included and underwent anatomic single-bundle reconstruction using an independent tunnel drilling technique and a minimum of 24 months' follow-up. The primary outcome assessed was the presence or absence of ACL rerupture. Secondary clinical outcomes consisted of the International Knee Documentation Committee, University of California at Los Angeles (UCLA) ACL quality of life assessment, and the visual analog pain scale. Between February 2010 and April 2013, 95 patients with isolated ACL tears between ages 18 and 40 met the inclusion criteria and were enrolled. Seventy-one autograft hamstring and 24 soft tissue hybrid graft ACL reconstructions were performed during the course of this study. The follow-up period was 24 to 32 months (mean 26.9 months). There were no statistically significant differences in patient demographics or Outerbridge classification. No statistically significant differences in ACL retears (5.6% auto, 4.2% hybrid; P = .57) were found between groups. Clinical International Knee Documentation Committee and UCLA ACL quality of life assessment improvement scores revealed no statistically significant differences in autograft and hybrid graft reconstructions (41 ± 11, 43 ± 13; P = .65) (38 ± 11, 40 ± 10; P = .23). The mean pain level decreased from 8.1 to 2.8 in the autograft group and 7.9 to 2.5 in the hybrid group (P = .18). The use of a hybrid soft tissue graft has a

  3. Synthetic bone graft versus autograft or allograft for spinal fusion: a systematic review.

    PubMed

    Buser, Zorica; Brodke, Darrel S; Youssef, Jim A; Meisel, Hans-Joerg; Myhre, Sue Lynn; Hashimoto, Robin; Park, Jong-Beom; Tim Yoon, S; Wang, Jeffrey C

    2016-10-01

    The purpose of this review was to compare the efficacy and safety of synthetic bone graft substitutes versus autograft or allograft for the treatment of lumbar and cervical spinal degenerative diseases. Multiple major medical reference databases were searched for studies that evaluated spinal fusion using synthetic bone graft substitutes (either alone or with an autograft or allograft) compared with autograft and allograft. Randomized controlled trials (RCT) and cohort studies with more than 10 patients were included. Radiographic fusion, patient-reported outcomes, and functional outcomes were the primary outcomes of interest. The search yielded 214 citations with 27 studies that met the inclusion criteria. For the patients with lumbar spinal degenerative disease, data from 19 comparative studies were included: 3 RCTs, 12 prospective, and 4 retrospective studies. Hydroxyapatite (HA), HA+collagen, β-tricalcium phosphate (β-TCP), calcium sulfate, or polymethylmethacrylate (PMMA) were used. Overall, there were no differences between the treatment groups in terms of fusion, functional outcomes, or complications, except in 1 study that found higher rates of HA graft absorption. For the patients with cervical degenerative conditions, data from 8 comparative studies were included: 4 RCTs and 4 cohort studies (1 prospective and 3 retrospective studies). Synthetic grafts included HA, β-TCP/HA, PMMA, and biocompatible osteoconductive polymer (BOP). The PMMA and BOP grafts led to lower fusion rates, and PMMA, HA, and BOP had greater risks of graft fragmentation, settling, and instrumentation problems compared with iliac crest bone graft. The overall quality of evidence evaluating the potential use and superiority of the synthetic biological materials for lumbar and cervical fusion in this systematic review was low or insufficient, largely due to the high potential for bias and small sample sizes. Thus, definitive conclusions or recommendations regarding the use of these

  4. Influence of insulin-like growth factor-I (IGF-I) on nerve autografts and tissue-engineered nerve grafts.

    PubMed

    Fansa, Hisham; Schneider, Wolfgang; Wolf, Gerald; Keilhoff, Gerburg

    2002-07-01

    To overcome the problems of limited donor nerves for nerve reconstruction, we established nerve grafts made from cultured Schwann cells and basal lamina from acellular muscle and used them to bridge a 2-cm defect of the rat sciatic nerve. Due to their basal lamina and to viable Schwann cells, these grafts allow regeneration that is comparable to autologous nerve grafts. In order to enhance regeneration, insulin-like growth factor (IGF-I) was locally applied via osmotic pumps. Autologous nerve grafts with and without IGF-I served as controls. Muscle weight ratio was significantly increased in the autograft group treated with IGF-I compared to the group with no treatment; no effect was evident in the tissue-engineered grafts. Autografts with IGF-I application revealed a significantly increased axon count and an improved g-ratio as indicator for "maturity" of axons compared to autografts without IGF-I. IGF-I application to the engineered grafts resulted in a decreased axon count compared to grafts without IGF-I. The g-ratio, however, revealed no significant difference between the groups. Local administration of IGF-I improves axonal regeneration in regular nerve grafts, but not in tissue-engineered grafts. Seemingly, in these grafts the interactive feedback mechanisms of neuron, glial cell, and extracellular matrix are not established, and IGF-I cannot exert its action as a pleiotrophic signal. Copyright 2002 Wiley Periodicals, Inc.

  5. Axial load-bearing capacity of an osteochondral autograft stabilized with a resorbable osteoconductive bone cement compared with a press-fit graft in a bovine model.

    PubMed

    Kiss, Marc-Olivier; Levasseur, Annie; Petit, Yvan; Lavigne, Patrick

    2012-05-01

    Osteochondral autografts in mosaicplasty are inserted in a press-fit fashion, and hence, patients are kept nonweightbearing for up to 2 months after surgery to allow bone healing and prevent complications. Very little has been published regarding alternative fixation techniques of those grafts. Osteochondral autografts stabilized with a resorbable osteoconductive bone cement would have a greater load-bearing capacity than standard press-fit grafts. Controlled laboratory study. Biomechanical testing was conducted on 8 pairs of cadaveric bovine distal femurs. For the first 4 pairs, 6 single osteochondral autografts were inserted in a press-fit fashion on one femur. On the contralateral femur, 6 grafts were stabilized with a calcium triglyceride osteoconductive bone cement. For the 4 remaining pairs of femurs, 4 groups of 3 adjacent press-fit grafts were inserted on one femur, whereas on the contralateral femur, grafts were cemented. After a maturation period of 48 hours, axial loading was applied on all single grafts and on the middle graft of each 3-in-a-row series. For the single-graft configuration, median loads required to sink the press-fit and cemented grafts by 2 and 3 mm were 281.87 N versus 345.56 N (P = .015) and 336.29 N versus 454.08 N (P = .018), respectively. For the 3-in-a-row configuration, median loads required to sink the press-fit and cemented grafts by 2 and 3 mm were 260.31 N versus 353.47 N (P = .035) and 384.83 N versus 455.68 N (P = .029), respectively. Fixation of osteochondral grafts using bone cement appears to improve immediate stability over the original mosaicplasty technique for both single- and multiple-graft configurations. Achieving greater primary stability of osteochondral grafts could potentially accelerate postoperative recovery, allowing early weightbearing and physical therapy.

  6. Articulated Bone Block for Posterior Cruciate Ligament Reconstruction Using Bone-Patellar Tendon-Bone Autograft: Surgical Technique to Facilitate Graft Passage.

    PubMed

    Cugat, Ramón; Alentorn-Geli, Eduard; Cuscó, Xavier; Navarro, Jordi; Steinbacher, Gilbert; Álvarez-Díaz, Pedro; Seijas, Roberto; Barastegui, David; García-Balletbó, Montse

    2018-02-01

    Posterior cruciate ligament reconstruction using the transtibial technique provides successful clinical outcomes. However, a bone-patellar tendon-bone (BTB) autograft with the transtibial technique has not been used by some surgeons because of concerns with graft passage from the tibial to the femoral tunnels (sharp turn) that can damage graft fibers. In the present surgical technique, an arthroscopic, transtibial, single-bundle technique for posterior cruciate ligament reconstruction using the BTB autograft with an easy and effective technical tip to facilitate graft passage is presented. Once the BTB is harvested, the femoral bone block is divided into 2 equal-sized blocks providing an articulated structure while preserving the tendon component. This facilitates the passage of the BTB tendon once it is entered in the posterior tibia and the graft has to make a sharp turn to reach the femoral tunnel. This easy and effective technique tip may avoid graft damage during the sharp turn, while maintaining all the advantages of a BTB autograft (bone-to-bone healing, own tissue with fast incorporation, and strong fixation and stability).

  7. Grafting of burns with widely meshed autograft split skin and Langerhans cell-depressed allograft split skin overlay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alsbjoern, B.F.S.; Sorensen, B.

    1986-12-01

    Extensively burned patients suffer from lack of sufficient autologous donor skin. Meshing and wide expansion of the obtained split skin has met the requirement to a large degree. However, the wider the expansion, the less chance of a proper take. By covering widely expanded autografts with viable cadaver split skin, the take has been improved. If the epidermal Langerhans cells in the cadaver split skin are depressed by ultraviolet B light and glucocorticosteroids before grafting, a prolonged allograft take can be achieved and the healing of the underlying autografts is ensured for an extended period. Grafting results in 6 patientsmore » with extensive burns are reported.« less

  8. Effect of skin graft thickness on scar development in a porcine burn model.

    PubMed

    DeBruler, Danielle M; Blackstone, Britani N; McFarland, Kevin L; Baumann, Molly E; Supp, Dorothy M; Bailey, J Kevin; Powell, Heather M

    2018-06-01

    Animal models provide a way to investigate scar therapies in a controlled environment. It is necessary to produce uniform, reproducible scars with high anatomic and biologic similarity to human scars to better evaluate the efficacy of treatment strategies and to develop new treatments. In this study, scar development and maturation were assessed in a porcine full-thickness burn model with immediate excision and split-thickness autograft coverage. Red Duroc pigs were treated with split-thickness autografts of varying thickness: 0.026in. ("thin") or 0.058in. ("thick"). Additionally, the thin skin grafts were meshed and expanded at 1:1.5 or 1:4 to evaluate the role of skin expansion in scar formation. Overall, the burn-excise-autograft model resulted in thick, raised scars. Treatment with thick split-thickness skin grafts resulted in less contraction and reduced scarring as well as improved biomechanics. Thin skin autograft expansion at a 1:4 ratio tended to result in scars that contracted more with increased scar height compared to the 1:1.5 expansion ratio. All treatment groups showed Matrix Metalloproteinase 2 (MMP2) and Transforming Growth Factor β1 (TGF-β1) expression that increased over time and peaked 4 weeks after grafting. Burns treated with thick split-thickness grafts showed decreased expression of pro-inflammatory genes 1 week after grafting, including insulin-like growth factor 1 (IGF-1) and TGF-β1, compared to wounds treated with thin split-thickness grafts. Overall, the burn-excise-autograft model using split-thickness autograft meshed and expanded to 1:1.5 or 1:4, resulted in thick, raised scars similar in appearance and structure to human hypertrophic scars. This model can be used in future studies to study burn treatment outcomes and new therapies. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

  9. Increased Risk of Revision After Anterior Cruciate Ligament Reconstruction With Soft Tissue Allografts Compared With Autografts: Graft Processing and Time Make a Difference.

    PubMed

    Maletis, Gregory B; Chen, Jason; Inacio, Maria C S; Love, Rebecca M; Funahashi, Tadashi T

    2017-07-01

    The optimal graft for anterior cruciate ligament reconstruction (ACLR) remains controversial. To compare the risk of aseptic revision between bone-patellar tendon-bone (BPTB) autografts, hamstring autografts, and soft tissue allografts. Cohort study; Level of evidence, 2. Prospectively collected ACLR cases reconstructed with BPTB autografts, hamstring autografts, and soft tissue allografts were identified using the Kaiser Permanente ACLR Registry. Aseptic revision was the endpoint. The type of graft and allograft processing method (nonprocessed, <1.8-Mrad irradiation with and without chemical processing [Allowash or AlloTrue], ≥1.8-Mrad irradiation with and without chemical processing, and chemical processing alone [BioCleanse]) were the exposures evaluated. Analyses were adjusted for age, sex, and race. Kaplan-Meier curves and Cox proportional hazards models were employed. The cohort included 14,015 cases: there were 8924 (63.7%) male patients, there were 6397 (45.6%) white patients, 4557 (32.5%) ACLRs used BPTB autografts, 3751 ACLRs (26.8%) used soft tissue allografts, and 5707 (40.7%) ACLRs used hamstring autografts. The median age was 34.6 years for soft tissue allografts, 24.3 years for hamstring autografts, and 22.0 years for BPTB autografts. The crude nonadjusted revision rates were 85 (1.9%) in BPTB autograft cases, 132 (2.3%) in hamstring autograft cases, and 83 (2.2%) in soft tissue allograft cases. After adjusting for age, sex, and race, compared with hamstring autografts, a higher risk of revision was found with allografts with ≥1.8 Mrad without chemical processing after 2.5 years (hazard ratio [HR], 3.88; 95% CI, 1.48-10.12) and ≥1.8 Mrad with chemical processing after 1 year (HR, 3.43; 95% CI, 1.58-7.47) and with BioCleanse processed grafts at any time point (HR, 3.02; 95% CI, 1.40-6.50). Nonprocessed allografts and those irradiated with <1.8 Mrad with or without chemical processing were not found to have a different risk of revision compared

  10. Iliac Crest Bone Graft versus Local Autograft or Allograft for Lumbar Spinal Fusion: A Systematic Review.

    PubMed

    Tuchman, Alexander; Brodke, Darrel S; Youssef, Jim A; Meisel, Hans-Jörg; Dettori, Joseph R; Park, Jong-Beom; Yoon, S Tim; Wang, Jeffrey C

    2016-09-01

    Systematic review. To compare the effectiveness and safety between iliac crest bone graft (ICBG) and local autologous bone and allograft in the lumbar spine. A systematic search of multiple major medical reference databases identified studies evaluating spinal fusion in patients with degenerative joint disease using ICBG, local autograft, or allograft in the thoracolumbar spine. Six comparative studies met our inclusion criteria. A "low" strength of the overall body of evidence suggested no difference in fusion percentages in the lumbar spine between local autograft and ICBG. We found no difference in fusion percentages based on low evidence comparing allograft with ICBG autograft. There were no differences in pain or functional results comparing local autograft or allograft with ICBG autograft. Donor site pain and hematoma/seroma occurred more frequently in ICBG autograft group for lumbar fusion procedures. There was low evidence around the estimate of patients with donor site pain following ICBG harvesting, ranging from 16.7 to 20%. With respect to revision, low evidence demonstrated no difference between allograft and ICBG autograft. There was no evidence comparing patients receiving allograft with local autograft for fusion, pain, functional, and safety outcomes. In the lumbar spine, ICBG, local autograft, and allograft have similar effectiveness in terms of fusion rates, pain scores, and functional outcomes. However, ICBG is associated with an increased risk for donor site-related complications. Significant limitations exist in the available literature when comparing ICBG, local autograft, and allograft for lumbar fusion, and thus ICBG versus other fusion methods necessitates further investigation.

  11. Iliac Crest Bone Graft versus Local Autograft or Allograft for Lumbar Spinal Fusion: A Systematic Review

    PubMed Central

    Tuchman, Alexander; Brodke, Darrel S.; Youssef, Jim A.; Meisel, Hans-Jörg; Dettori, Joseph R.; Park, Jong-Beom; Yoon, S. Tim; Wang, Jeffrey C.

    2016-01-01

    Study Design  Systematic review. Objective  To compare the effectiveness and safety between iliac crest bone graft (ICBG) and local autologous bone and allograft in the lumbar spine. Methods  A systematic search of multiple major medical reference databases identified studies evaluating spinal fusion in patients with degenerative joint disease using ICBG, local autograft, or allograft in the thoracolumbar spine. Results  Six comparative studies met our inclusion criteria. A “low” strength of the overall body of evidence suggested no difference in fusion percentages in the lumbar spine between local autograft and ICBG. We found no difference in fusion percentages based on low evidence comparing allograft with ICBG autograft. There were no differences in pain or functional results comparing local autograft or allograft with ICBG autograft. Donor site pain and hematoma/seroma occurred more frequently in ICBG autograft group for lumbar fusion procedures. There was low evidence around the estimate of patients with donor site pain following ICBG harvesting, ranging from 16.7 to 20%. With respect to revision, low evidence demonstrated no difference between allograft and ICBG autograft. There was no evidence comparing patients receiving allograft with local autograft for fusion, pain, functional, and safety outcomes. Conclusion  In the lumbar spine, ICBG, local autograft, and allograft have similar effectiveness in terms of fusion rates, pain scores, and functional outcomes. However, ICBG is associated with an increased risk for donor site-related complications. Significant limitations exist in the available literature when comparing ICBG, local autograft, and allograft for lumbar fusion, and thus ICBG versus other fusion methods necessitates further investigation. PMID:27556001

  12. Editorial Commentary: The Jury Remains Out on Hybrid Autograft-Plus-Allograft for Diminutive Hamstring Anterior Cruciate Ligament Autografts.

    PubMed

    Dhawan, Aman

    2016-11-01

    In a Level III, single center, retrospective, nonrandomized observational study, anterior cruciate ligament reconstruction revision rates and patient-reported outcomes were found to be similar at 2-year follow-up when using autograft hamstrings versus a hybrid graft (autograft and nonirradiated allograft), with both groups reporting low levels of revisions and excellent outcomes. Despite previous published data that were cause for concern, a study in this issue provides support for use of a hybrid graft technique when encountering the challenging situation of a diminutive hamstring autograft when performing anterior cruciate ligament reconstruction. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  13. Adhesion monitoring of skin grafts by photoacoustic measurement: experiment using rat allograft models

    NASA Astrophysics Data System (ADS)

    Yamazaki, Mutsuo; Sato, Shunichi; Saito, Daizo; Okada, Yoshiaki; Ashida, Hiroshi; Obara, Minoru

    2004-07-01

    Adhesion monitoring of grafted skins is very important in successful treatment of severe burns and traumas. However, current diagnosis of skin grafting is usually done by visual observation, which is not reliable and gives no quantitative information on the skin graft adhesion. When the grafted skin adheres well, neovascularities will be generated in the grafted skin tissue, and therefore adhesion may be monitored by detecting the neovascularities. In this study, we attempted to measure photoacoustic signals originate from the neovascularities by irradiating the grafted skins with 532-nm nanosecond light pulses in rat autograft and allograft models. The measurement showed that immediately after skin grafting, photoacoustic signal originate from the blood in the dermis was negligibly small, while 6 - 24 hours after skin grafting, signal was observed from the dermis in the graft. We did not observe a significant difference between the signals from the autograft and the allograft models. These results indicate that neovascularization would take place within 6 hours after skin grafting, and the rejection reaction would make little effect on adhesion within early hours after grafting.

  14. Fresh Osteochondral Allograft Versus Autograft: Twelve-Month Results in Isolated Canine Knee Defects.

    PubMed

    McCarty, Eric C; Fader, Ryan R; Mitchell, Justin J; Glenn, R Edward; Potter, Hollis G; Spindler, Kurt P

    2016-09-01

    Osteochondral autografts and allografts have been widely used in the treatment of isolated grade 4 articular cartilage lesions of the knee. However, there is a paucity of literature regarding the basic science investigating the direct comparison between fresh osteochondral allografts to autografts. At 12 months, fresh osteochondral allografts are equal to autografts with respect to function, bony incorporation into host bone, and chondrocyte viability. Controlled laboratory study. Eight adult mongrel dogs underwent bilateral hindlimb osteochondral graft implantation in the knee after creation of an acute Outerbridge grade 4 cartilage defect. One hindlimb of each dog knee received an autograft, and the contralateral knee received an allograft. All dogs were sacrificed at 12 months. Graft analysis included gross examination, radiographs, magnetic resonance imaging (MRI), biomechanical testing, and histology. MRI demonstrated excellent bony incorporation of both autografts and allografts, except for 1 allograft that revealed partial incorporation. Histologic examination of cartilage showed intact hyaline appearance for both autografts and allografts, with fibrocartilage at the host-graft interface of both. Biomechanical testing demonstrated no significant difference between allografts and autografts (P = .76). Furthermore, no significant difference was observed between allografts and the native cartilage with biomechanical testing (P = .84). After 12 months from time of implantation, fresh osteochondral allograft tissue and autograft tissue in this study were not statistically different with respect to biomechanical properties, gross morphology, bony incorporation, or overall histologic characteristics. When compared with the previously reported 6-month incorporation rates, there was improved allograft and autograft incorporation at 12 months. With no significant differences in gross examination, radiographs, MRI, biomechanical testing, or histology in the canine

  15. A comparison of revision and rerupture rates of ACL reconstruction between autografts and allografts in the skeletally immature.

    PubMed

    Nelson, Ian R; Chen, Jason; Love, Rebecca; Davis, Brent R; Maletis, Gregory B; Funahashi, Tadashi T

    2016-03-01

    Anterior cruciate ligament reconstructions (ACLRs) in skeletally immature patients are increasing. The purpose of this study is to describe the demographics, graft usage, revision, and re-operation rates in skeletally immature ACLRs in the Kaiser Permanente healthcare system. Skeletally immature patients (<17.0 years old with open physes) were identified using the Kaiser Permanente ACLR registry. Multi-ligament reconstructions and physeal-sparing ACLRs were excluded. Aseptic revision and same-knee re-operation were the outcomes of interest. Exposure of interest was graft type; bone-patellar-tendon-bone (BPTB) autograft, hamstring autograft, and any type of allograft. Age, gender, body mass index (BMI), and race were evaluated as confounders. Cox proportional hazard models stratified by surgeon were used to analyse the risk of revision and re-operation. A total of 534 primary ACLR cases were evaluated with a mean follow-up of 2.9 years. The majority were hamstring autografts (n = 388, 72.7%), male (n = 339, 63.9%), and White (n = 232, 43.4%). Median age was 14.9 years, and median BMI was 21.9 kg/m(2). There were 44 (8.2%) aseptic revisions and 48 (9.0%) same-knee re-operations. The incidence rate for revision was BPTB autograft 5.5%, hamstring autograft 7.5%, and allograft 13.2%. After adjusting for confounders and surgeon clustering effect, the risk of aseptic revision and revision between allograft and hamstring autograft did not reach statistical significance. Graft selection differs in skeletally immature patients with a preponderance of surgeries being performed with hamstring tendon autografts. High revision rates were identified for all graft types used, though differences in revision rates across different graft types did not reach statistical significance. Surgeons should be aware of high rates of revision in this skeletally immature young population, although type of graft used did not appear to make a difference. III.

  16. Histological comparison of autograft, allograft-DBM, xenograft, and synthetic grafts in a trabecular bone defect: an experimental study in rabbits.

    PubMed

    Athanasiou, Vasilis T; Papachristou, Dionysios J; Panagopoulos, Andreas; Saridis, Alkis; Scopa, Chrisoula D; Megas, Panagiotis

    2010-01-01

    Different types of bone-graft substitutes have been developed and are on the market worldwide to eliminate the drawbacks of autogenous grafting. This experimental animal study was undertaken to evaluate the different histological properties of various bone graft substitutes utilized in this hospital. Ninety New Zealand white rabbits were divided into six groups of 15 animals. Under general anesthesia, a 4.5 mm-wide hole was drilled into both the lateral femoral condyles of each rabbit, for a total of 180 condyles for analysis. The bone defects were filled with various grafts, these being 1) autograft, 2) DBM crunch allograft (Grafton), 3) bovine cancellous bone xenograft (Lubboc), 4) calcium phosphate hydroxyapatite substitute (Ceraform), 5) calcium sulfate substitute (Osteoset), and 6) no filling (control). The animals were sacrificed at 1, 3, and 6 months after implantation and tissue samples from the implanted areas were processed for histological evaluation. A histological grading scale was designed to determine the different histological parameters of bone healing. The highest histological grades were achieved with the use of cancellous bone autograft. Bovine xenograft (Lubboc) was the second best in the histological scale grading. The other substitutes (Grafton, Ceraform, Osteoset) had similar scores but were inferior to both allograft and xenograft. Bovine xenograft showed better biological response than the other bone graft substitutes; however, more clinical studies are necessary to determine its overall effectiveness.

  17. Prefabricated microvascular autograft in tracheal reconstruction.

    PubMed

    Fayad, J; Kuriloff, D B

    1994-10-01

    Tracheal reconstruction continues to be a challenge in head and neck surgery. Numerous techniques, including the use of alloplasts, composite grafts, and staged laryngotracheal troughs, have met with limited success because of implant exposure, infection, persistent granulation tissue, and eventual restenosis. With recently introduced techniques for soft-tissue molding, bone induction with bone morphogenetic protein, and microvascular free tissue transfer, a rodent model was developed to create a well-vascularized tracheal autograft. In this model, a rigid tube having the same dimensions and flexibility as the native trachea was created by wrapping a cylindrical silicone tracheal mold with a layer of vascularized adductor thigh muscle pedicled on the femoral vessels in the groin. Tracheal rings were created by filing transverse troughs in the muscle bed with bone morphogenetic protein-primed demineralized bone matrix before wrapping around the silicone mold. Grafts harvested at 2 weeks demonstrated rigid skeletal support provided by heterotopic bone formation in the form of rings and a smooth inner lining produced by fibroplasia. Bone transformation was controlled and restricted to the muscle troughs, allowing intervening regions of soft tissue and thus producing a flexible neotrachia. With this model, a homologous, vascularized tracheal autograft capable of microvascular free tissue transfer was fabricated based on the femoral vessels. Prefabrication of composite grafts, through the use of soft-tissue molding, bone induction, and subsequent free tissue transfer, has an unlimited potential for use in head and neck reconstruction.

  18. Fibrin glue versus autologous blood for conjunctival autograft fixation in pterygium surgery.

    PubMed

    Boucher, Sophie; Conlon, Ronan; Teja, Salina; Teichman, Joshua C; Yeung, Season; Ziai, Setareh; Baig, Kashif

    2015-08-01

    To compare the outcomes between autologous blood- and fibrin glue-fixated conjunctival autografts in pterygium excision surgery. Retrospective case series. Forty eyes of 40 patients who had a primary nasal pterygium excision. A retrospective comparative case series of 40 eyes (40 patients) that had a primary nasal pterygium excision. All eyes had a conjunctival autograft from the superior bulbar conjunctiva to cover the scleral bed. Twenty eyes (20 patients) had fixation of the autograft using autologous blood (AB), and 20 eyes (20 patients) had fixation using fibrin glue (FG). One year of follow-up data included conjunctival graft stability (graft loss, graft retraction), pterygium recurrence, visual acuity, and postoperative complications. Descriptive and inferential statistics were performed. Intraoperatively, no complications occurred in either group. Graft loss occurred in 6 patients in the AB group, compared with none in the FG group. Graft retraction occurred in 3 patients in the AB group and 2 patients in the FG group. At 1 year postoperatively, pterygium recurrence occurred in 4 patients in the AB group and 1 patient in the FG group. One patient in the AB group developed a small pyogenic granuloma that resolved by 6 months with conservative management. Visual acuity remained stable in both groups. Conjunctival autograft fixation with autologous blood resulted in less stable conjunctival autografts and a higher recurrence rate compared with fixation with fibrin glue. Copyright © 2015 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

  19. Total venous inflow occlusion and pericardial auto-graft reconstruction for right atrial hemangiosarcoma resection in a dog.

    PubMed

    Verbeke, Fei; Binst, Dominique; Stegen, Ludo; Waelbers, Tim; de Rooster, Hilde; Van Goethem, Bart

    2012-10-01

    A sizeable right atrial hemangiosarcoma in a 6-year-old Bordeaux dog, World Health Organization (WHO) stage 2, was excised using total venous inflow occlusion. The defect was restored with a non-vascularized pericardial auto-graft. The dog had a disease-free interval of 7 mo. The dog was euthanized 9 months later, at which time there were distant metastases but no indication of local recurrence.

  20. Total venous inflow occlusion and pericardial auto-graft reconstruction for right atrial hemangiosarcoma resection in a dog

    PubMed Central

    Verbeke, Fei; Binst, Dominique; Stegen, Ludo; Waelbers, Tim; de Rooster, Hilde; Van Goethem, Bart

    2012-01-01

    A sizeable right atrial hemangiosarcoma in a 6-year-old Bordeaux dog, World Health Organization (WHO) stage 2, was excised using total venous inflow occlusion. The defect was restored with a non-vascularized pericardial auto-graft. The dog had a disease-free interval of 7 mo. The dog was euthanized 9 months later, at which time there were distant metastases but no indication of local recurrence. PMID:23543933

  1. Autograft versus nonirradiated allograft tissue for anterior cruciate ligament reconstruction: a systematic review.

    PubMed

    Mariscalco, Michael W; Magnussen, Robert A; Mehta, Divyesh; Hewett, Timothy E; Flanigan, David C; Kaeding, Christopher C

    2014-02-01

    An autograft has traditionally been the gold standard for anterior cruciate ligament reconstruction (ACLR), but the use of allograft tissue has increased in recent years. While numerous studies have demonstrated that irradiated allografts are associated with increased failure rates, some report excellent results after ACLR with nonirradiated allografts. The purpose of this systematic review was to determine whether the use of nonirradiated allograft tissue is associated with poorer outcomes when compared with autografts. Patients undergoing ACLR with autografts versus nonirradiated allografts will demonstrate no significant differences in graft failure risk, laxity on postoperative physical examination, or differences in patient-oriented outcome scores. Systematic review. A systematic review was performed to identify prospective or retrospective comparative studies (evidence level 1, 2, or 3) of autografts versus nonirradiated allografts for ACLR. Outcome data included graft failure based on clinical findings and instrumented laxity, postoperative laxity on physical examination, and patient-reported outcome scores. Studies were excluded if they did not specify whether the allograft had been irradiated. Quality assessment and data extraction were performed by 2 examiners. Nine studies comparing autografts and nonirradiated allografts were included. Six of the 9 studies compared bone-patellar tendon-bone (BPTB) autografts with BPTB allografts. Two studies compared hamstring tendon autografts to hamstring tendon allografts, and 1 study compared hamstring tendon autografts to tibialis anterior allografts. The mean patient age in 7 of 9 studies ranged from 24.5 to 32 years, with 1 study including only patients older than 40 years and another not reporting patient age. The mean follow-up duration was 24 to 94 months. Six of 9 studies reported clinical graft failure rates, 8 of 9 reported postoperative instrumented laxity measurements, 7 of 9 reported postoperative

  2. Quadriceps tendon autograft for arthroscopic knee ligament reconstruction: use it now, use it often.

    PubMed

    Sheean, Andrew J; Musahl, Volker; Slone, Harris S; Xerogeanes, John W; Milinkovic, Danko; Fink, Christian; Hoser, Christian

    2018-04-28

    Traditional bone-patellar tendon-bone and hamstring tendon ACL grafts are not without limitations. A growing body of anatomic, biomechanical and clinical data has demonstrated the utility of quadriceps tendon autograft in arthroscopic knee ligament reconstruction. The quadriceps tendon autograft provides a robust volume of tissue that can be reliably harvested, mitigating the likelihood of variably sized grafts and obviating the necessity of allograft augmentation. Modern, minimally invasive harvest techniques offer the advantages of low rates of donor site morbidity and residual extensor mechanism strength deficits. New data suggest that quadriceps tendon autograft may possess superior biomechanical characteristics when compared with bone-patella tendon-bone (BPTB) autograft. However, there have been very few direct, prospective comparisons between the clinical outcomes associated with quadriceps tendon autograft and other autograft options (eg, hamstring tendon and bone-patellar tendon-bone). Nevertheless, quadriceps tendon autograft should be one of the primary options in any knee surgeon's armamentarium. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  3. Carbon dioxide laser ablation with immediate autografting in a full-thickness porcine burn model.

    PubMed Central

    Glatter, R D; Goldberg, J S; Schomacker, K T; Compton, C C; Flotte, T J; Bua, D P; Greaves, K W; Nishioka, N S; Sheridan, R L

    1998-01-01

    OBJECTIVE: To compare the long-term clinical and histologic outcome of immediate autografting of full-thickness burn wounds ablated with a high-power continuous-wave CO2 laser to sharply débrided wounds in a porcine model. SUMMARY BACKGROUND DATA: Continuous-wave CO2 lasers have performed poorly as tools for burn excision because the large amount of thermal damage to viable subeschar tissues precluded successful autografting. However, a new technique, in which a high-power laser is rapidly scanned over the eschar, results in eschar vaporization without significant damage to underlying viable tissues, allowing successful immediate autografting. METHODS: Full-thickness paravertebral burn wounds measuring 36 cm2 were created on 11 farm swine. Wounds were ablated to adipose tissue 48 hours later using either a surgical blade or a 150-Watt continuous-wave CO2 laser deflected by an x-y galvanometric scanner that translated the beam over the tissue surface, removing 200 microm of tissue per scan. Both sites were immediately autografted and serially evaluated clinically and histologically for 180 days. RESULTS: The laser-treated sites were nearly bloodless. The mean residual thermal damage was 0.18+/-0.05 mm. The mean graft take was 96+/-11% in manual sites and 93+/-8% in laser sites. On postoperative day 7, the thickness of granulation tissue at the graft-wound bed interface was greater in laser-debrided sites. By postoperative day 180, the manual and laser sites were histologically identical. Vancouver scar assessment revealed no differences in scarring at postoperative day 180. CONCLUSIONS: Long-term scarring, based on Vancouver scar assessments and histologic evaluation, was equivalent at 6 months in laser-ablated and sharply excised sites. Should this technology become practical, the potential clinical implications include a reduction in surgical blood loss without sacrifice of immediate engraftment rates or long-term outcome. Images Figure 1. Figure 2. Figure 3

  4. The viability of cryopreserved onlay cranial bone allografts: a comparative experimental study versus fresh autografts.

    PubMed

    Sanz, J; Elejabeitia, J; Bazán, A; García-Tutor, E; Paloma, V

    1996-04-01

    It is well known that calvarial bone autografts are the bone grafts that are the least reabsorbent and have the best long-term evolution in craniofacial surgery. However, they do have certain limitations: (1) reabsorption results in repeated surgery and the need for new donor areas, (2) a limited amount of autogenous cranial bone is available (due to avoiding areas close to cranial sutures and venous sinuses, and because the temporal bone is very fragile and the cranium has not fully developed in children), and (3) graft extraction increases surgical time and morbidity. Because of this, we present an alternative to calvarial bone autografts: cryopreserved allografts. This paper is an experimental prospective study carried out on sheep with the following goals: (1) to assess the behavior of calvarial onlay bone grafts cryopreserved at -80 degrees C, using fresh autografts implanted under the same conditions as controls; (2) to compare reabsorption percentages statistically over time; and (3) to study qualitatively any histological variations. The results obtained are (1) more reabsorption of allografts when compared to autografts (at 90 days, 21.97% versus 20.21% of grafted volume), although this difference is not statistically significant; (2) a reduction in height in all onlay grafts as a consequence of the loss of the diplöe; (3) the absence of any type of inflammation caused by a reaction to cryopreserved allografts; and (4) bone substitution performed using frozen allografts is histologically similar to that using fresh autografts.

  5. Allograft Augmentation of Hamstring Autograft for Younger Patients Undergoing Anterior Cruciate Ligament Reconstruction.

    PubMed

    Jacobs, Cale A; Burnham, Jeremy M; Makhni, Eric; Malempati, Chaitu S; Swart, Eric; Johnson, Darren L

    2017-03-01

    Younger patients and those with smaller hamstring autograft diameters have been shown to be at significantly greater risk of graft failure after anterior cruciate ligament (ACL) reconstruction. To date, there is no information in the literature about the clinical success and/or cost-effectiveness of increasing graft diameter by augmenting with semitendinosus allograft tissue for younger patients. Hybrid hamstring grafts are a cost-effective treatment option because of a reduced rate of graft failure. Cohort study (economic and decision analysis); Level of evidence, 3. We retrospectively identified patients younger than 18 years who had undergone ACL reconstruction by a single surgeon between 2010 and 2015. During this period, the operating surgeon's graft selection algorithm included the use of bone-patellar tendon-bone (BTB) autografts for the majority of patients younger than 18 years. However, hamstring autografts (hamstring) or hybrid hamstring autografts with allograft augment (hybrid) were used in skeletally immature patients and in those whom the surgeon felt might have greater difficulty with postoperative rehabilitation after BTB graft harvest. Patient demographics, graft type, graft diameter, the time the patient was cleared to return to activity, and the need for secondary surgical procedures were compared between the hamstring and hybrid groups. The clinical results were then used to assess the potential cost-effectiveness of hybrid grafts in this select group of young patients with an ACL injury or reconstruction. This study comprised 88 patients (hamstring group, n = 46; hybrid group, n = 42). The 2 groups did not differ in terms of age, sex, timing of return to activity, or prevalence of skeletally immature patients. Graft diameters were significantly smaller in the hamstring group (7.8 vs 9.9 mm; P < .001), which corresponded with a significantly greater rate of graft failure (13 of 46 [28.3%] vs 5 of 42 [11.9%]; P = .049). As a result of the

  6. Conjunctival autograft for pterygium

    PubMed Central

    Clearfield, Elizabeth; Muthappan, Valliammai; Wang, Xue; Kuo, Irene C

    2016-01-01

    Database (LILACS) (1982 to November 2015), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) (last searched 21 November 2014), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 23 November 2015. Selection criteria We included in this review randomized controlled trials that had compared conjunctival autograft surgery (with or without adjunctive therapy) with amniotic membrane graft surgery (with or without adjunctive therapy) in people with primary or recurrent pterygium. Data collection and analysis Two review authors independently screened search results and assessed full-text reports from among the potentially eligible trials. Two review authors independently extracted data from the included trials and assessed the trial characteristics and risk of bias. The primary outcome was the risk of recurrence of pterygium at 3 months and 6 months after surgery. We combined results from individual studies in meta-analyses using random-effects models. Risk of recurrence of pterygium was reported using risk ratios to compare conjunctival autograft with amniotic membrane transplant. Main results We identified 20 studies that had analyzed a total of 1947 eyes of 1866 participants (individual studies ranged from 8 to 346 participants who were randomized). The studies were conducted in eight different countries: one in Brazil, three in China, three in Cuba, one in Egypt, two in Iran, two in Thailand, seven in Turkey, and one in Venezuela. Overall risk of bias was unclear, as many studies did not provide information on randomization methods or masking to prevent performance and detection bias. The risk ratio for recurrence of pterygium using conjunctival autograft versus amniotic membrane transplant was 0.87 (95

  7. Conjunctival autograft for pterygium.

    PubMed

    Clearfield, Elizabeth; Muthappan, Valliammai; Wang, Xue; Kuo, Irene C

    2016-02-11

    2015), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) (last searched 21 November 2014), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 23 November 2015. We included in this review randomized controlled trials that had compared conjunctival autograft surgery (with or without adjunctive therapy) with amniotic membrane graft surgery (with or without adjunctive therapy) in people with primary or recurrent pterygium. Two review authors independently screened search results and assessed full-text reports from among the potentially eligible trials. Two review authors independently extracted data from the included trials and assessed the trial characteristics and risk of bias. The primary outcome was the risk of recurrence of pterygium at 3 months and 6 months after surgery. We combined results from individual studies in meta-analyses using random-effects models. Risk of recurrence of pterygium was reported using risk ratios to compare conjunctival autograft with amniotic membrane transplant. We identified 20 studies that had analyzed a total of 1947 eyes of 1866 participants (individual studies ranged from 8 to 346 participants who were randomized). The studies were conducted in eight different countries: one in Brazil, three in China, three in Cuba, one in Egypt, two in Iran, two in Thailand, seven in Turkey, and one in Venezuela. Overall risk of bias was unclear, as many studies did not provide information on randomization methods or masking to prevent performance and detection bias.The risk ratio for recurrence of pterygium using conjunctival autograft versus amniotic membrane transplant was 0.87 (95% confidence interval (CI) 0.43 to 1.77) and 0.53 (95% CI 0.33 to 0.85) at 3 months and 6 months

  8. Hamstring autograft size importance in anterior cruciate ligament repair surgery

    PubMed Central

    Figueroa, Francisco; Figueroa, David; Espregueira-Mendes, João

    2018-01-01

    Graft size in hamstring autograft anterior cruciate ligament (ACL) surgery is an important factor directly related to failure. Most of the evidence in the field suggests that the size of the graft in hamstring autograft ACL reconstruction matters when the surgeon is trying to avoid failures. The exact graft diameter needed to avoid failures is not absolutely clear and could depend on other factors, but newer studies suggest than even increases of 0.5 mm up to a graft size of 10 mm are beneficial for the patient. There is still no evidence to recommend the use of grafts > 10 mm. Several methods – e.g. folding the graft in more strands – that are simple and reproducible have been published lately to address the problem of having an insufficient graft size when performing an ACL reconstruction. Due to the evidence presented, we think it is necessary for the surgeon to have them in his or her arsenal before performing an ACL reconstruction. There are obviously other factors that should be considered, especially age. Therefore, a larger graft size should not be taken as the only goal in ACL reconstruction. Cite this article: EFORT Open Rev 2018;3:93-97. DOI: 10.1302/2058-5241.3.170038 PMID:29657850

  9. Hamstring autograft size importance in anterior cruciate ligament repair surgery.

    PubMed

    Figueroa, Francisco; Figueroa, David; Espregueira-Mendes, João

    2018-03-01

    Graft size in hamstring autograft anterior cruciate ligament (ACL) surgery is an important factor directly related to failure. Most of the evidence in the field suggests that the size of the graft in hamstring autograft ACL reconstruction matters when the surgeon is trying to avoid failures.The exact graft diameter needed to avoid failures is not absolutely clear and could depend on other factors, but newer studies suggest than even increases of 0.5 mm up to a graft size of 10 mm are beneficial for the patient. There is still no evidence to recommend the use of grafts > 10 mm.Several methods - e.g. folding the graft in more strands - that are simple and reproducible have been published lately to address the problem of having an insufficient graft size when performing an ACL reconstruction. Due to the evidence presented, we think it is necessary for the surgeon to have them in his or her arsenal before performing an ACL reconstruction.There are obviously other factors that should be considered, especially age. Therefore, a larger graft size should not be taken as the only goal in ACL reconstruction. Cite this article: EFORT Open Rev 2018;3:93-97. DOI: 10.1302/2058-5241.3.170038.

  10. Comparison of acellular dermal graft and palatal autograft in the reconstruction of keratinized gingiva around dental implants: a case report.

    PubMed

    Yan, Ji-Jong; Tsai, Alex Yi-Min; Wong, Man-Ying; Hou, Lein-Tuan

    2006-06-01

    The use of autogenous gingival grafts has proved to be an effective and predictable way to increase the amount of keratinized gingiva. However, discomfort and pain at the donor site are unavoidable. Acellular dermal matrix (ADM) allograft can be used as a donor tissue to eliminate the need for another surgical site and alleviate pain and trauma. The purpose of this study was to evaluate the effectiveness of ADM allograft in increasing the width of keratinized gingiva around dental implants. A patient with inadequate keratinized gingiva around dental implants in maxillary and mandibular anterior regions received either an ADM graft or palatal autograft by random allocation. The width of keratinized gingiva and other clinical periodontal parameters were recorded initially and at 3 and 6 months after surgery. Both grafts provided satisfactory results. The width of keratinized tissues was increased by using the ADM allograft, but by a lesser amount than seen with the autogenous gingival graft.

  11. Athymic Rat Model for Evaluation of Engineered Anterior Cruciate Ligament Grafts

    PubMed Central

    Leong, Natalie L.; Kabir, Nima; Arshi, Armin; Nazemi, Azadeh; Wu, Ben M.; McAllister, David R.; Petrigliano, Frank A.

    2015-01-01

    Anterior cruciate ligament (ACL) rupture is a common ligamentous injury that often requires surgery because the ACL does not heal well without intervention. Current treatment strategies include ligament reconstruction with either autograft or allograft, which each have their associated limitations. Thus, there is interest in designing a tissue-engineered graft for use in ACL reconstruction. We describe the fabrication of an electrospun polymer graft for use in ACL tissue engineering. This polycaprolactone graft is biocompatible, biodegradable, porous, and is comprised of aligned fibers. Because an animal model is necessary to evaluate such a graft, this paper describes an intra-articular athymic rat model of ACL reconstruction that can be used to evaluate engineered grafts, including those seeded with xenogeneic cells. Representative histology and biomechanical testing results at 16 weeks postoperatively are presented, with grafts tested immediately post-implantation and contralateral native ACLs serving as controls. The present study provides a reproducible animal model with which to evaluate tissue engineered ACL grafts, and demonstrates the potential of a regenerative medicine approach to treatment of ACL rupture. PMID:25867958

  12. Comparison of clinical outcomes and second-look arthroscopic findings after ACL reconstruction using a hamstring autograft or a tibialis allograft.

    PubMed

    Yoo, Seung-Hyun; Song, Eun-Kyoo; Shin, Young-Rok; Kim, Sung-Kyu; Seon, Jong-Keun

    2017-04-01

    The purpose of this prospective randomized clinical study was to compare the clinical and radiological outcomes, including tibial tunnel widening and the progression of osteoarthritis after ACL reconstruction using a hamstring autograft or a tibialis allograft. In addition, we compared the graft tear and synovial coverage of grafts in patients that underwent the second-look arthroscopy. Among 184 patients with an ACL injury who underwent ACL reconstruction, 68 patients of autograft group and 64 patients of tibialis allograft group were included for this study after minimum of 2-year follow-up. The Lachman and pivot-shift tests, Tegner activity score, Lysholm knee score, and IKDC score were compared between the two groups. The quadriceps and hamstring isokinetic strengths using dynamometer were also compared. Degree of OA was determined using the Kellgren-Lawrence grading system on the weight-bearing radiographs. In total, 51 patients (26 patients in autograft group and 25 in the tibialis allograft group) underwent the second-look arthroscopy, in which we compared the apparent tear of graft and synovial coverage of grafts. At the final follow-up, there were no statistical significances in the two groups in Lachman and pivot-shift tests (n.s.). The Tegner activity, Lysholm knee score, and IKDC scores were similar in the two groups. Moreover, no significant differences were observed in the muscle power (n.s.). Some patients showed the progression of OA (five in autograft and four in allograft groups) without intergroup difference (n.s.). Regarding the findings of second-look arthroscopy, although there was no significant difference in graft tear, synovial coverage was better in autograft group than in allograft group. Even though hamstring autografts and tibialis allografts provided good functional outcomes without significant differences, the second-look arthroscopy revealed that hamstring autografts produced better synovial coverage than tibialis allograft. I.

  13. Autologous Blood Versus Fibrin Glue in Pterygium Excision With Conjunctival Autograft Surgery.

    PubMed

    Nadarajah, Gaayathri; Ratnalingam, Vanitha Hema; Mohd Isa, Hazlita

    2017-04-01

    To evaluate graft stability and recurrence rate between fibrin glue and autologous blood in pterygium conjunctival autograft surgery. A prospective, randomized, single-blinded clinical trial to assess the efficacy of autologous blood in place of fibrin glue in pterygium surgery. A total of 120 eyes of 111 patients were randomized according to pterygium morphology, to undergo pterygium surgery with autografting using either autologous blood or fibrin glue. All patients were operated by a single surgeon; 58 eyes were operated using fibrin glue and 62 eyes had a conjunctival autograft with autologous blood. Patients were seen on postoperative day 1, 1 week, 1 month, 6 months, and 1 year after surgery. Graft stability and pterygium recurrence were graded by an independent observer who was masked to the method of treatment. All 120 eyes completed the 1-year follow-up. Graft loss was seen only in the autologous blood group. Of the 62 eyes in this group, a total of 15 (24.2%) grafts dislodged. Recurrence was calculated after excluding grafts that were dislodged. Of the 105 patients, there were a total of 7 recurrences, 2 (3.4%) from the fibrin adhesive method and 5 (10.6%) from the autologous blood method. This was not statistically significant (P = 0.238). Autologous blood does not exhibit similar graft stability seen with fibrin glue. Although the recurrence rate may not be significant, careful patient selection and a standard method needs to be laid out before the use of this method is widely accepted.

  14. Iliac crest autograft versus alternative constructs for anterior cervical spine surgery: Pros, cons, and costs

    PubMed Central

    Epstein, Nancy E.

    2012-01-01

    Background: Grafting choices available for performing anterior cervical diskectomy/fusion (ACDF) procedures have become a major concern for spinal surgeons, and their institutions. The “gold standard”, iliac crest autograft, may still be the best and least expensive grafting option; it deserves to be reassessed along with the pros, cons, and costs for alternative grafts/spacers. Methods: Although single or multilevel ACDF have utilized iliac crest autograft for decades, the implant industry now offers multiple alternative grafting and spacer devices; (allografts, cages, polyether-etherketone (PEEK) amongst others). While most studies have focused on fusion rates and clinical outcomes following ACDF, few have analyzed the “value-added” of these various constructs (e.g. safety/efficacy, risks/complications, costs). Results: The majority of studies document 95%-100% fusion rates when iliac crest autograft is utilized to perform single level ACDF (X-ray or CT confirmed at 6-12 postoperative months). Although many allograft studies similarly quote 90%-100% fusion rates (X-ray alone confirmed at 6-12 postoperative months), a recent “post hoc analysis of data from a prospective multicenter trial” (Riew KD et. al., CSRS Abstract Dec. 2011; unpublished) revealed a much higher delayed fusion rate using allografts at one year 55.7%, 2 years 87%, and four years 92%. Conclusion: Iliac crest autograft utilized for single or multilevel ACDF is associated with the highest fusion, lowest complication rates, and significantly lower costs compared with allograft, cages, PEEK, or other grafts. As spinal surgeons and institutions become more cost conscious, we will have to account for the “value added” of these increasingly expensive graft constructs. PMID:22905321

  15. Conjunctivolimbal Autograft Using a Fibrin Adhesive in Pterygium Surgery

    PubMed Central

    Kim, Hyun Ho; Mun, Hong Jae; Lee, Kyoo Won; Shin, Jae Pil

    2008-01-01

    Purpose To evaluate the efficacy and safety of fibrin bioadhesive in conjunctivolimbal autograft surgery for primary pterygium. Methods Thirty-six eyes in 34 patients were reviewed with nasal primary pterygium who were treated with pterygium excision with superior conjunctivolimbal transplantation with fibrin bioadhesive. Surgical durations were recorded and the patients were followed up on the first day after surgery and then at 1, 2, 4, 8 and 12 weeks postoperatively. The graft-recipient site attachments were examined and subjective symptoms of patients were recorded at every follow-up examinations. Results The mean patient age was 57.9±10.1 (ranging from 33 to 83) years. The mean follow-up period was 22.05±5.78 weeks. The mean surgery time was 18.04±5.65 minutes. The subjective symptoms (pain, foreign body sensation, tearing and discomfort) disappeared in 23 of 36 eyes (64%) in one week after surgery, and all discomforts subsided within two weeks after surgery in all patients. The conjunctivolimbal autograft was correctly positioned and fixed in 34 of 36 eyes (94.4%) throughout the follow-up period. Graft dehiscence was seen in two eyes (5.6%), one eye was treated with remedial sutures, and the other eye showed a spontaneous healing without remedial sutures. Transient graft edema occurred in four eyes (11.2%) but subsided spontaneously within a month. There were no cases of pterygium regrowth or complications due to the fibrin bioadhesive. Conclusions The use of fibrin bioadhesive in conjunctivolimbal autograft surgery in primary pterygium simplifies surgical techniques, shorten surgical duration, and produce less postoperative subjective symptoms. Therefore, the fibrin bioadhesive is a safe and effective tool to attach conjunctivolimbal autograft in primary pterygium surgery. PMID:18784440

  16. Pain level after ACL reconstruction: A comparative study between free quadriceps tendon and hamstring tendons autografts.

    PubMed

    Buescu, Cristian Tudor; Onutu, Adela Hilda; Lucaciu, Dan Osvald; Todor, Adrian

    2017-03-01

    The objective of this study was to compare the pain levels and analgesic consumption after single bundle ACL reconstruction with free quadriceps tendon autograft versus hamstring tendon autograft. A total of 48 patients scheduled for anatomic single-bundle ACL reconstruction were randomized into two groups: the free quadriceps tendon autograft group (24 patients) and the hamstring tendons autograft group (24 patients). A basic multimodal analgesic postoperative program was used for all patients and rescue analgesia was provided with tramadol, at pain scores over 30 on the Visual Analog Scale. The time to the first rescue analgesic, the number of doses of tramadol and pain scores were recorded. The results within the same group were compared with the Wilcoxon signed test. Supplementary analgesic drug administration proved significantly higher in the group of subjects with hamstring grafts, with a median (interquartile range) of 1 (1.3) dose, compared to the group of subjects treated with a quadriceps graft, median = 0.5 (0.1.25) (p = 0.009). A significantly higher number of subjects with a quadriceps graft did not require any supplementary analgesic drug (50%) as compared with subjects with hamstring graft (13%; Z-statistics = 3.01, p = 0.002). The percentage of subjects who required a supplementary analgesic drug was 38% higher in the HT group compared with the FQT group. The use of the free quadriceps tendon autograft for ACL reconstruction leads to less pain and analgesic consumption in the immediate postoperative period compared with the use of hamstrings autograft. Level I Therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  17. Anterior Cruciate Ligament Reconstruction in a Rabbit Model Using Silk-Collagen Scaffold and Comparison with Autograft

    PubMed Central

    Bi, Fanggang; Shi, Zhongli; Liu, An; Guo, Peng; Yan, Shigui

    2015-01-01

    The objective of the present study was to perform an in vivo assessment of a novel silk-collagen scaffold for anterior cruciate ligament (ACL) reconstruction. First, a silk-collagen scaffold was fabricated by combining sericin-extracted knitted silk fibroin mesh and type I collagen to mimic the components of the ligament. Scaffolds were electron-beam sterilized and rolled up to replace the ACL in 20 rabbits in the scaffold group, and autologous semitendinosus tendons were used to reconstruct the ACL in the autograft control group. At 4 and 16 weeks after surgery, grafts were retrieved and analyzed for neoligament regeneration and tendon-bone healing. To evaluate neoligament regeneration, H&E and immunohistochemical staining was performed, and to assess tendon-bone healing, micro-CT, biomechanical test, H&E and Russell-Movat pentachrome staining were performed. Cell infiltration increased over time in the scaffold group, and abundant fibroblast-like cells were found in the core of the scaffold graft at 16 weeks postoperatively. Tenascin-C was strongly positive in newly regenerated tissue at 4 and 16 weeks postoperatively in the scaffold group, similar to observations in the autograft group. Compared with the autograft group, tendon-bone healing was better in the scaffold group with trabecular bone growth into the scaffold. The results indicate that the silk-collagen scaffold has considerable potential for clinical application. PMID:25938408

  18. Role of anthropometric data in the prediction of 4-stranded hamstring graft size in anterior cruciate ligament reconstruction.

    PubMed

    Ho, Sean Wei Loong; Tan, Teong Jin Lester; Lee, Keng Thiam

    2016-03-01

    To evaluate whether pre-operative anthropometric data can predict the optimal diameter and length of hamstring tendon autograft for anterior cruciate ligament (ACL) reconstruction. This was a cohort study that involved 169 patients who underwent single-bundle ACL reconstruction (single surgeon) with 4-stranded MM Gracilis and MM Semi-Tendinosus autografts. Height, weight, body mass index (BMI), gender, race, age and -smoking status were recorded pre-operatively. Intra-operatively, the diameter and functional length of the 4-stranded autograft was recorded. Multiple regression analysis was used to determine the relationship between the anthropometric measurements and the length and diameter of the implanted autografts. The strongest correlation between 4-stranded hamstring autograft diameter was height and weight. This correlation was stronger in females than males. BMI had a moderate correlation with the diameter of the graft in females. Females had a significantly smaller graft both in diameter and length when compared with males. Linear regression models did not show any significant correlation between hamstring autograft length with height and weight (p>0.05). Simple regression analysis demonstrated that height and weight can be used to predict hamstring graft diameter. The following regression equation was obtained for females: Graft diameter=0.012+0.034*Height+0.026*Weight (R2=0.358, p=0.004) The following regression equation was obtained for males: Graft diameter=5.130+0.012*Height+0.007*Weight (R2=0.086, p=0.002). Pre-operative anthropometric data has a positive correlation with the diameter of 4 stranded hamstring autografts but no significant correlation with the length. This data can be utilised to predict the autograft diameter and may be useful for pre-operative planning and patient counseling for graft selection.

  19. Results of a prospective randomized controlled trial of early ambulation for patients with lower extremity autografts.

    PubMed

    Lorello, David John; Peck, Michael; Albrecht, Marlene; Richey, Karen J; Pressman, Melissa A

    2014-01-01

    It is common practice to keep those patients with lower extremity autografts immobile until post-operative day (POD) 5. There is however inherent risks associated with even short periods of immobility. As of now there are no randomized controlled trials looking at early ambulation of patients with lower extremity autografts in the burn community.The objective of this study was to show that patients who begin ambulation within 24 hours of lower extremity autografting will have no increased risk of graft failure than those patients who remain immobile until POD 5. Thirty-one subjects who received autografts to the lower extremity were randomized after surgery into either the early ambulation group (EAG;17 subjects) or the standard treatment group (STG;14 subjects). Those subjects randomized to the EAG began ambulating with physical therapy on POD 1. Subjects in the STG maintained bed rest until POD 5. There was no difference in the number of patients with graft loss in either the EAG or STG on POD 5, and during any of the follow-up visits. No subjects required regrafting. There was a significant difference in the mean minutes of ambulation, with the EAG ambulating longer than the STG (EAG 23.4 minutes [SD 12.03], STG 14.1 [SD 9.00], P=.0235) on POD 5. Burn patients with lower extremity autografts can safely ambulate on POD 1 without fear of graft failure compared with those patients that remain on bed rest for 5 days.

  20. Long-term results of bone-retinaculum-bone autograft for scapholunate instability.

    PubMed

    Soong, Maximillian; Merrell, Gregory A; Ortmann, Fred; Weiss, Arnold-Peter C

    2013-03-01

    To report long-term follow-up of scapholunate interosseous ligament reconstruction with bone-retinaculum-bone autograft in patients with dynamic scapholunate instability. Of the 14 patients from the previously reported cohort who had bone-retinaculum-bone autograft for dynamic instability, 6 returned for clinical examination and radiographs, 3 were reached by telephone, and 2 were lost to follow-up. The remaining 3 had salvage procedures (2 total wrist arthrodeses and 1 proximal row carpectomy) between the prior report and the current study and thus reached an endpoint, at 2 to 4 years. For the 6 who returned, outcome measurements included scapholunate angle and gap, radiographic evidence of secondary arthritis, wrist extension and flexion, grip strength, and Mayo wrist score. Follow-up averaged 11.9 years (range, 10.7-14.1 y). Clinical and radiographic outcomes deteriorated moderately from the prior report. Mayo wrist score averaged 83. There were 3 failures, resulting in 1 proximal row carpectomy and 2 total wrist arthrodeses. Findings at repeat surgery in the failed group included an intact graft without any apparent abnormalities, a partially ruptured graft (after a subsequent re-injury), and a completely resorbed graft. Bone-retinaculum-bone autograft reconstruction is a viable treatment option for dynamic scapholunate instability in which the scaphoid and lunate can be reduced. Results may deteriorate but are similar to those reported previously from other techniques. Problems with graft strength or stiffness may necessitate further surgery. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  1. Computed Tomography and Optical Imaging of Osteogenesis-angiogenesis Coupling to Assess Integration of Cranial Bone Autografts and Allografts.

    PubMed

    Cohn Yakubovich, Doron; Tawackoli, Wafa; Sheyn, Dmitriy; Kallai, Ilan; Da, Xiaoyu; Pelled, Gadi; Gazit, Dan; Gazit, Zulma

    2015-12-22

    A major parameter determining the success of a bone-grafting procedure is vascularization of the area surrounding the graft. We hypothesized that implantation of a bone autograft would induce greater bone regeneration by abundant blood vessel formation. To investigate the effect of the graft on neovascularization at the defect site, we developed a micro-computed tomography (µCT) approach to characterize newly forming blood vessels, which involves systemic perfusion of the animal with a polymerizing contrast agent. This method enables detailed vascular analysis of an organ in its entirety. Additionally, blood perfusion was assessed using fluorescence imaging (FLI) of a blood-borne fluorescent agent. Bone formation was quantified by FLI using a hydroxyapatite-targeted probe and µCT analysis. Stem cell recruitment was monitored by bioluminescence imaging (BLI) of transgenic mice that express luciferase under the control of the osteocalcin promoter. Here we describe and demonstrate preparation of the allograft, calvarial defect surgery, µCT scanning protocols for the neovascularization study and bone formation analysis (including the in vivo perfusion of contrast agent), and the protocol for data analysis. The 3D high-resolution analysis of vasculature demonstrated significantly greater angiogenesis in animals with implanted autografts, especially with respect to arteriole formation. Accordingly, blood perfusion was significantly higher in the autograft group by the 7(th) day after surgery. We observed superior bone mineralization and measured greater bone formation in animals that received autografts. Autograft implantation induced resident stem cell recruitment to the graft-host bone suture, where the cells differentiated into bone-forming cells between the 7(th) and 10(th) postoperative day. This finding means that enhanced bone formation may be attributed to the augmented vascular feeding that characterizes autograft implantation. The methods depicted may serve

  2. THE RESPONSE OF X-IRRADIATED LIMBS OF ADULT URODELES TO NORMAL TISSUE GRAFTS. I. EFFECTS OF AUTOGRAFTS OF SIXTY-DAY FOREARM REGENERATES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stinson, B.D.

    1963-06-01

    Results are reported of autoplastic transplantation of parts of nonirradiated, regenerated forelimb to the contralateral x-irradiated forelimb in adult Triturus viridescens. The right forelimbs were exposed to various doses of localized irradiation (1000 to 5000 r) followed by amputation of both left and right forelimbs through the mid forearm. Left limbs regenerated normally, but irradiated right limbs failed to exhibit any significant degree of regenerative activity over a 3-month period. Both forelimbs were reamputated through the distal humerus and observed for an additional two months. Left limbs produced normal regenerates, but irradiated right limbs gave no gross evidence of regenerationmore » at any of the radiation dose levels. Normal left regenerates were reamputated immediately distal to the elbow on the 60th day after the second amputation; the severed forearm was trimmed with scissors along anterior and posterior borders and denuded of skin over its proximal half, leaving an essentially complete forearm region as a normal autograft. This was implanted into the irradiated right upper arm stump, after ablation of the distal half of its humerus, with normal proximodistal polarity in all cases. The irradiated stump was reamputated through the distal portion of the implanted normal autograft two weeks after implantation, and was observed for four months. Periodic gross observations showed that over 90% of irradiated upper arms formed regenerates at a rate which paralleled that of nonirradiated controls. However, regenerates formed on irradiated upper arms exhibited a restriction of morphogenetic capacity, only 60% attaining 3- and 4-digit stages. Most of the morphologically more complex regenerates which developed on the irradiated upper arm stumps manifested left limb asymmetry despite their formation on right irradiated stumps, suggesting a relation between the asymmetry of the normal graft and that of the resulting regenerate. All regenerates which

  3. The Effect of Iliac Crest Autograft on the Outcome of Fusion in the Setting of Degenerative Spondylolisthesis

    PubMed Central

    Radcliff, Kristen; Hwang, Raymond; Hilibrand, Alan; Smith, Harvey E.; Gruskay, Jordan; Lurie, Jon D.; Zhao, Wenyan; Albert, Todd; Weinstein, James

    2012-01-01

    Background: There is considerable controversy about the long-term morbidity associated with the use of posterior autologous iliac crest bone graft for lumbar spine fusion procedures compared with the use of bone-graft substitutes. The hypothesis of this study was that there is no long-term difference in outcome for patients who had posterior lumbar fusion with or without iliac crest autograft. Methods: The study population includes patients enrolled in the degenerative spondylolisthesis cohort of the Spine Patient Outcomes Research Trial who underwent lumbar spinal fusion. Patients were divided according to whether they had or had not received posterior autologous iliac crest bone graft. Results: There were 108 patients who had fusion with iliac crest autograft and 246 who had fusion without iliac crest autograft. There were no baseline differences between groups in demographic characteristics, comorbidities, or baseline clinical scores. At baseline, the group that received iliac crest bone graft had an increased percentage of patients who had multilevel fusions (32% versus 21%; p = 0.033) and L5-S1 surgery (37% versus 26%; p = 0.031) compared with the group without iliac crest autograft. Operative time was higher in the iliac crest bone-graft group (233.4 versus 200.9 minutes; p < 0.001), and there was a trend toward increased blood loss (686.9 versus 582.3; p = 0.057). There were no significant differences in postoperative complications, including infection or reoperation rates, between the groups. On the basis of the numbers available, no significant differences were detected between the groups treated with or without iliac crest bone graft with regard to the scores on Short Form-36, Oswestry Disability Index, Stenosis Bothersomeness Index, and Low Back Pain Bothersomeness Scale or the percent of patient satisfaction with symptoms averaged over the study period. Conclusions: The outcome scores associated with the use of posterior iliac crest bone graft for

  4. Autograft versus Allograft for Cervical Spinal Fusion

    PubMed Central

    Brodke, Darrel S.; Youssef, Jim A.; Meisel, Hans-Jörg; Dettori, Joseph R.; Park, Jong-Beom; Yoon, S. Tim; Wang, Jeffrey C.

    2017-01-01

    Study Design Systematic review. Objective To compare the effectiveness and safety between iliac crest bone graft (ICBG), non-ICBG autologous bone, and allograft in cervical spine fusion. To avoid problems at the donor site, various allograft materials have been used as a substitute for autograft. However, there are still questions as to the comparative effectiveness and safety of cadaver allograft compared with autologous ICBG. Methods A systematic search of multiple major medical reference databases was conducted to identify studies evaluating spinal fusion in patients with cervical degenerative disk disease using ICBG compared with non-ICBG autograft or allograft or non-ICBG autograft compared with allograft in the cervical spine. Radiographic fusion, patient-reported outcomes, and functional outcomes were the primary outcomes of interest. Adverse events were evaluated for safety. Results The search identified 13 comparative studies that met our inclusion criteria: 2 prospective cohort studies and 11 retrospective cohort studies. Twelve cohort studies compared allograft with ICBG autograft during anterior cervical fusion and demonstrated with a low evidence level of support that there are no differences in fusion percentages, pain scores, or functional results. There was insufficient evidence comparing patients receiving allograft with non-ICBG autograft for fusion, pain, revision, and functional and safety outcomes. No publications directly comparing non-ICBG autograft with ICBG were found. Conclusion Although the available literature suggests ICBG and allograft may have similar effectiveness in terms of fusion rates, pain scores, and functional outcomes following anterior cervical fusion, there are too many limitations in the available literature to draw any significant conclusions. No individual study provided greater than class III evidence, and when evaluating the overall body of literature, no conclusion had better than low evidence support. A prospective

  5. The Degree of Knee Extension Does Not Affect Postoperative Stability or Subsequent Graft Tear Rate After Anterior Cruciate Ligament Reconstruction With Patellar Tendon Autograft.

    PubMed

    Benner, Rodney W; Shelbourne, K Donald; Gray, Tinker

    2016-04-01

    There is concern that high degrees of hyperextension may lead to an increase in graft laxity or graft failure after anterior cruciate ligament (ACL) reconstruction. Patients with a high degree of hyperextension will have a higher rate of graft tear/failure and lower subjective scores after surgery compared with patients with less knee extension. Cohort study, Level of evidence, 2. Of 2329 patients who underwent ACL reconstruction with patellar tendon autograft between 1998 and 2008, there were 625 patients who met the inclusion criteria of having primary ACL surgery, no bilateral ACL injuries, no existing osteoarthritis, and having either ≥6° of knee hyperextension before and after surgery (group A: n = 318; mean hyperextension, 8° ± 2° [range, 6°-15°]) or ≤3° of knee hyperextension before and after surgery (group B: n = 307; mean hyperextension, 0° ± 3° [range, 3° hyperextension to -4° short of 0° neutral]). KT-1000 arthrometer manual maximum difference between knees, range of motion measurements, and subjective follow-up with International Knee Documentation Committee (IKDC) and Cincinnati Knee Ratings Scale (CKRS) surveys were used to evaluate results. Subsequent graft tear related to specific injury within 5 years of surgery was recorded. Graft failure was defined as a KT-1000 manual maximum difference of >5 mm. Follow-up was obtained from 278 (87%) in group A and 275 (90%) in group B at a mean of 4.1 ± 1.1 years after surgery. The KT-1000 arthrometer manual maximum difference between knees was 2.0 ± 1.4 in group A and 2.1 ± 1.6 in group B (P = .701). Subsequent ACL graft tear/failure occurred in 22 patients (6.9%) in group A and 30 patients (9.8%) in group B (P = .246). Further subanalysis showed that the graft tear/failure rate was 6 of 81 (7.4%) for patients with ≥10° of hyperextension versus 16 of 237 (6.8%) for patients with 6° to 9° of hyperextension. There was no difference in IKDC or CKRS scores between groups after surgery (P

  6. Randomized prospective study comparing tri-cortical iliac crest autograft to allograft in the lateral column lengthening component for operative correction of adult acquired flatfoot deformity.

    PubMed

    Dolan, Christopher M; Henning, Jeffrey A; Anderson, John G; Bohay, Donald R; Kornmesser, Marc J; Endres, Terrence J

    2007-01-01

    Operative treatment of stage II posterior tibial tendon insufficiency (PTTI) is controversial. Many soft-tissue and bony procedures and various combinations of the two have been reported for treatment of stage II PTTI. Orthopaedists recognize the lateral column lengthening component of the procedure as a successful reconstructive technique. The use of cortical allograft for lateral column lengthening in the correction of pes planus in the pediatric patient population has been routine. In the adult population, however, tricortical iliac crest autograft has been the bone graft of choice. Harvest of this autograft can precipitate significant morbidity and cost. Therefore, we undertook this randomized controlled trial to compare graft incorporation and healing of allograft and autograft in the lateral column lengthening component of adult flatfoot reconstruction. Lateral column lengthening was done as a component of operative correction for stage II PTTI in adult patients (older than 18 years) by two surgeons using similar procedures. The patients were randomized to either the allograft or autograft procedures. The primary endpoint was graft incorporation and healing as assessed by radiographs. The study included 33 randomized feet in 31 patients. We followed 18 feet in the allograft group and 15 in the autograft group to the point of union. There were 21 women and 10 men. There were no delayed unions, nonunions, or hardware failures. All patients in both groups achieved bony union by the 12-week followup evaluation. Two superficial foot infections were successfully treated with oral antibiotics. Two patients in the autograft group continued to have hip donor site pain at 3 months. This study suggests that union rates of allograft and autograft (iliac crest bone graft) are equal. The use of allograft in the lateral column lengthening component of operative correction of adult stage II PTTI appears to be a viable alternative to the use of iliac crest autograft and

  7. One-stage Revision ACL reconstruction with hamstring autograft results in satisfactory outcome

    PubMed Central

    Kejriwal, Ritwik; Buelow, Jens

    2017-01-01

    Objectives: Revision anterior cruciate ligament (ACL) reconstruction is associated with poorer outcomes and higher rerupture rates when compared to primary ACL reconstruction. There is also a significant heterogeneity in surgical technique, number of stages, and graft options. We report a large single surgeon case series with hamstring autograft as a graft option. Methods: Observational series of revision ACL reconstructions performed by the senior author between 2005 and 2015 was carried out. Chart reviews and clinic follow-ups were performed with the following recorded – re-rupture rate, radiographic grading of osteoarthritis, KT-1000 arthrometer test, IKDC outcome scores and knee range of motion. All patients underwent single bundle four-strand hamstring autograft performed in one stage with use of new tunnels in majority of the cases. Results: 66 patients underwent hamstring autograft one-stage revision ACL reconstruction by Dr Jens Buelow. Chart review was carried out on all patients, and 26 (39%) were followed up in clinic and/or by phone with a mean follow up of 4.7 years. Outcomes included re-rupture rate of 4.5%, reoperation rate of 12%, mean visual analogue scale score of 7.6, mean side-to-side difference of 2.6 mm for KT-1000 arthrometer test, and mean IKDC score of 79. Of the 17 patients with radiographs, 40% had moderate osteoarthritis (grade 2 or 3) at follow-up. Conclusion: Revision ACL reconstruction can result in a satisfactory outcome when performed with a hamstring autograft in one stage.

  8. Effect of graft choice on the outcome of revision anterior cruciate ligament reconstruction in the Multicenter ACL Revision Study (MARS) Cohort.

    PubMed

    2014-10-01

    Most surgeons believe that graft choice for anterior cruciate ligament (ACL) reconstruction is an important factor related to outcome; however, graft choice for revision may be limited due to previously used grafts. Autograft use would result in increased sports function, increased activity level, and decreased osteoarthritis symptoms (as measured by validated patient-reported outcome instruments). Autograft use would result in decreased graft failure and reoperation rate 2 years after revision ACL reconstruction. Cohort study; Level of evidence, 2. Patients undergoing revision ACL reconstruction were identified and prospectively enrolled by 83 surgeons at 52 sites. Data collected included baseline demographics, surgical technique, pathologic abnormalities, and the results of a series of validated, patient-reported outcome instruments (International Knee Documentation Committee [IKDC], Knee injury and Osteoarthritis Outcome Score [KOOS], Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], and Marx activity rating score). Patients were followed up at 2 years and asked to complete the identical set of outcome instruments. Incidences of additional surgery and reoperation due to graft failure were also recorded. Multivariate regression models were used to determine the predictors (risk factors) of IKDC, KOOS, WOMAC, Marx scores, graft rerupture, and reoperation rate at 2 years after revision surgery. A total of 1205 patients (697 [58%] males) were enrolled. The median age was 26 years. In 88% of patients, this was their first revision, and 341 patients (28%) were undergoing revision by the surgeon who had performed the previous reconstruction. The median time since last ACL reconstruction was 3.4 years. Revision using an autograft was performed in 583 patients (48%), allograft was used in 590 (49%), and both types were used in 32 (3%). Questionnaire follow-up was obtained for 989 subjects (82%), while telephone follow-up was obtained for 1112 (92

  9. Novel experimental surgical strategy to prevent traumatic neuroma formation by combining a 3D-printed Y-tube with an autograft.

    PubMed

    Bolleboom, Anne; de Ruiter, Godard C W; Coert, J Henk; Tuk, Bastiaan; Holstege, Jan C; van Neck, Johan W

    2018-02-09

    OBJECTIVE Traumatic neuromas may develop after nerve injury at the proximal nerve stump, which can lead to neuropathic pain. These neuromas are often resistant to therapy, and excision of the neuroma frequently leads to recurrence. In this study, the authors present a novel surgical strategy to prevent neuroma formation based on the principle of centro-central anastomosis (CCA), but rather than directly connecting the nerve ends to an autograft, they created a loop using a 3D-printed polyethylene Y-shaped conduit with an autograft in the distal outlets. METHODS The 3D-printed Y-tube with autograft was investigated in a model of rat sciatic nerve transection in which the Y-tube was placed on the proximal sciatic nerve stump and a peroneal graft was placed between the distal outlets of the Y-tube to form a closed loop. This model was compared with a CCA model, in which a loop was created between the proximal tibial and peroneal nerves with a peroneal autograft. Additional control groups consisted of the closed Y-tube and the extended-arm Y-tube. Results were analyzed at 12 weeks of survival using nerve morphometry for the occurrence of neuroma formation and axonal regeneration in plastic semi-thin sections. RESULTS Among the different surgical groups, the Y-tube with interposed autograft was the only model that did not result in neuroma formation at 12 weeks of survival. In addition, a 13% reduction in the number of myelinated axons regenerating through the interposed autograft was observed in the Y-tube with autograft model. In the CCA model, the authors also observed a decrease of 17% in the number of myelinated axons, but neuroma formation was present in this model. The closed Y-tube resulted in minimal nerve regeneration inside the tube together with extensive neuroma formation before the entrance of the tube. The extended-arm Y-tube model clearly showed that the majority of the regenerating axons merged into the Y-tube arm, which was connected to the autograft

  10. Effect of graft choice on the outcome of revision anterior cruciate ligament reconstruction in the Multicenter ACL Revision Study (MARS) Cohort

    PubMed Central

    Wright, Rick W.; Huston, Laura J.; Haas, Amanda K.; Spindler, Kurt P.; Nwosu, Sam K.; Allen, Christina R.; Anderson, Allen F.; Cooper, Daniel E.; DeBerardino, Thomas M.; Dunn, Warren R.; Lantz, Brett (Brick) A.; Stuart, Michael J.; Garofoli, Elizabeth A.; Albright, John P.; Amendola, Annunziato (Ned); Andrish, Jack T.; Annunziata, Christopher C.; Arciero, Robert A.; Bach, Bernard R.; Baker, Champ L.; Bartolozzi, Arthur R.; Baumgarten, Keith M.; Bechler, Jeffery R.; Berg, Jeffrey H.; Bernas, Geoffrey A.; Brockmeier, Stephen F.; Brophy, Robert H.; Bush-Joseph, Charles A.; Butler, J. Brad; Campbell, John D.; Carey, James L.; Carpenter, James E.; Cole, Brian J.; Cooper, Jonathan M.; Cox, Charles L.; Creighton, R. Alexander; Dahm, Diane L.; David, Tal S.; Flanigan, David C.; Frederick, Robert W.; Ganley, Theodore J.; Gatt, Charles J.; Gecha, Steven R.; Giffin, James Robert; Hame, Sharon L.; Hannafin, Jo A.; Harner, Christopher D.; Harris, Norman Lindsay; Hechtman, Keith S.; Hershman, Elliott B.; Hoellrich, Rudolf G.; Hosea, Timothy M.; Johnson, David C.; Johnson, Timothy S.; Jones, Morgan H.; Kaeding, Christopher C.; Kamath, Ganesh V.; Klootwyk, Thomas E.; Levy, Bruce A.; Ma, C. Benjamin; Maiers, G. Peter; Marx, Robert G.; Matava, Matthew J.; Mathien, Gregory M.; McAllister, David R.; McCarty, Eric C.; McCormack, Robert G.; Miller, Bruce S.; Nissen, Carl W.; O'Neill, Daniel F.; Owens, Brett D.; Parker, Richard D.; Purnell, Mark L.; Ramappa, Arun J.; Rauh, Michael A.; Rettig, Arthur C.; Sekiya, Jon K.; Shea, Kevin G.; Sherman, Orrin H.; Slauterbeck, James R.; Smith, Matthew V.; Spang, Jeffrey T.; Svoboda, Steven J.; Taft, Timothy N.; Tenuta, Joachim J.; Tingstad, Edwin M.; Vidal, Armando F.; Viskontas, Darius G.; White, Richard A.; Williams, James S.; Wolcott, Michelle L.; Wolf, Brian R.; York, James J.

    2015-01-01

    Background Most surgeons believe that graft choice for ACL reconstruction is an important factor related to outcome. Although graft choice may be limited in the revision setting based on previously used grafts, it is still felt to be important. Hypothesis The purpose of this study was to determine if revision ACL graft choice predicts outcomes related to sports function, activity level, OA symptoms, graft re-rupture, and reoperation at two years following revision reconstruction. We hypothesized that autograft use would result in increased sports function, increased activity level, and decreased OA symptoms (as measured by validated patient reported outcome instruments). Additionally, we hypothesized that autograft use would result in decreased graft failure and reoperation rate 2 years following revision ACL reconstruction. Study Design Prospective cohort study; Level of evidence, 2. Methods Revision ACL reconstruction patients were identified and prospectively enrolled by 83 surgeons over 52 sites. Data collected included baseline demographics, surgical technique and pathology, and a series of validated patient reported outcome instruments (IKDC, KOOS, WOMAC, and Marx activity rating score). Patients were followed up at 2 years, and asked to complete the identical set of outcome instruments. Incidence of additional surgery and reoperation due to graft failure were also recorded. Multivariate regression models were used to determine the predictors (risk factors) of IKDC, KOOS, WOMAC, Marx scores, graft re-rupture, and reoperation rate at 2 years following revision surgery. Results 1205 patients were successfully enrolled with 697 (58%) males. Median age was 26. In 88% this was their first revision. 341 (28%) were undergoing revision by the surgeon that had performed the previous reconstruction. 583 (48%) underwent revision reconstruction utilizing an autograft, 590 (49%) allograft, and 32 (3%) both autograft and allograft. Median time since their last ACL

  11. Integra as a Dermal Replacement in a Meshed Composite Skin Graft in a Rat Model: A One-Step Operative Procedure

    DTIC Science & Technology

    2002-01-01

    skin graft (MCSG) using Integra as a dermal template for a meshed split thickness autograft was developed in rats. The silicon layer of Integra was removed, the resulting dermal analogue was meshed (1:1.5), expanded, and placed on excised full thickness wound and covered with a meshed (1:1.5 or 1:6) split thickness autograft. Grafted wounds were dressed with BioBrane, Vaseline gauze, silver-impregnated nylon, or silver-nylon and direct current (SNDC). At scheduled intervals up to 3 months postgrafting, wounds were examined for epithelialization, collagen deposition and

  12. In vitro skin models and tissue engineering protocols for skin graft applications.

    PubMed

    Naves, Lucas B; Dhand, Chetna; Almeida, Luis; Rajamani, Lakshminarayanan; Ramakrishna, Seeram

    2016-11-30

    In this review, we present a brief introduction of the skin structure, a concise compilation of skin-related disorders, and a thorough discussion of different in vitro skin models, artificial skin substitutes, skin grafts, and dermal tissue engineering protocols. The advantages of the development of in vitro skin disorder models, such as UV radiation and the prototype model, melanoma model, wound healing model, psoriasis model, and full-thickness model are also discussed. Different types of skin grafts including allografts, autografts, allogeneic, and xenogeneic are described in detail with their associated applications. We also discuss different tissue engineering protocols for the design of various types of skin substitutes and their commercial outcomes. Brief highlights are given of the new generation three-dimensional printed scaffolds for tissue regeneration applications. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  13. Hamstring graft bacterial contamination during anterior cruciate ligament reconstruction: clinical and microbiological study.

    PubMed

    Badran, Mohamad Aboelnour; Moemen, Dalia Mohamed

    2016-09-01

    Autograft preparation for anterior cruciate ligament (ACL) reconstruction has a potential for graft contamination. The purpose of this study was to evaluate the possibility of bacterial contamination of hamstring autograft during preparation and when dropped onto the operating room floor and methods of graft decontamination. Sixty hamstring tendon autograft specimens were used as the test group. Excess tendon not used in the ACL procedure was divided into five segments. One segment, at the completion of preparation, was sent for culture as a control; the remaining four segments were dropped onto the floor adjacent to the surgical field for 15 seconds. One segment was cultured without undergoing any further treatment. Cultures were taken from each segment after immersion in 10 % povidone-iodine solution, 4 % chlorhexidine and bacitracin, respectively, for three minutes. Cultures of a skin swab and floor swab were taken at the same time and place that the ACL was dropped. Cultures of control graft tissue from ten patients (16.7 %) were positive for bacteria. No patient developed post-operative infection. Ninety organisms were identified, with Staphylococcus epidermidis being the most common isolate. Grafts rinsed in either bacitracin or 4 % chlorhexidine solutions were less likely to be culture positive. A high rate of contamination can be expected during autograft preparation for ACL reconstruction. Soaking the hamstring autograft in either bacitracin or 4 % chlorhexidine solution is effective for decontamination, particulary if graft is dropped on the floor.

  14. Autograft Versus Allograft Anterior Cruciate Ligament Reconstruction: A Prospective, Randomized Clinical Study With a Minimum 10-Year Follow-up.

    PubMed

    Bottoni, Craig R; Smith, Eric L; Shaha, James; Shaha, Steven S; Raybin, Sarah G; Tokish, John M; Rowles, Douglas J

    2015-10-01

    The use of allografts for anterior cruciate ligament (ACL) reconstruction in young athletes is controversial. No long-term results have been published comparing tibialis posterior allografts to hamstring autografts. To evaluate the long-term results of primary ACL reconstruction using either an allograft or autograft. Randomized controlled trial; Level of evidence, 1. From June 2002 to August 2003, patients with a symptomatic ACL-deficient knee were randomized to receive either a hamstring autograft or tibialis posterior allograft. All allografts were from a single tissue bank, aseptically processed, and fresh-frozen without terminal irradiation. Graft fixation was identical in all knees. All patients followed the same postoperative rehabilitation protocol, which was blinded to the therapists. Preoperative and postoperative assessments were performed via examination and/or telephone and Internet-based questionnaire to ascertain the functional and subjective status using established knee metrics. The primary outcome measures were graft integrity, subjective knee stability, and functional status. There were 99 patients (100 knees); 86 were men, and 95% were active-duty military. Both groups were similar in demographics and preoperative activity level. The mean and median ages of both groups were identical at 29 and 26 years, respectively. Concomitant meniscal and chondral pathologic abnormalities, microfracture, and meniscal repair performed at the time of reconstruction were similar in both groups. At a minimum of 10 years (range, 120-132 months) from surgery, 96 patients (97 knees) were contacted (2 patients were deceased, and 1 was unable to be located). There were 4 (8.3%) autograft and 13 (26.5%) allograft failures that required revision reconstruction. In the remaining patients whose graft was intact, there was no difference in the mean Single Assessment Numeric Evaluation, Tegner, or International Knee Documentation Committee scores. At a minimum of 10 years

  15. Early excision and grafting versus delayed excision and grafting of deep thermal burns up to 40% total body surface area: a comparison of outcome

    PubMed Central

    Saaiq, M.; Zaib, S.; Ahmad, S.

    2012-01-01

    Summary This is a study of 120 patients of either sex and all ages who had sustained deep burns of up to 40% of the total body surface area. Half the patients underwent early excision and skin autografting (i.e., within 4-7 days of sustaining burn injury) while the rest underwent delayed excision and skin autografting (i.e., within 1-4 weeks post-burn). Significant differences were found in favour of the early excision and grafting group with regard to the various burn management outcome parameters taken into consideration, i.e. culture positivity of wounds, graft take, duration of post-graft hospitalization, and mortality. PMID:23467391

  16. Autograft versus Allograft for Cervical Spinal Fusion: A Systematic Review.

    PubMed

    Tuchman, Alexander; Brodke, Darrel S; Youssef, Jim A; Meisel, Hans-Jörg; Dettori, Joseph R; Park, Jong-Beom; Yoon, S Tim; Wang, Jeffrey C

    2017-02-01

    Systematic review. To compare the effectiveness and safety between iliac crest bone graft (ICBG), non-ICBG autologous bone, and allograft in cervical spine fusion. To avoid problems at the donor site, various allograft materials have been used as a substitute for autograft. However, there are still questions as to the comparative effectiveness and safety of cadaver allograft compared with autologous ICBG. A systematic search of multiple major medical reference databases was conducted to identify studies evaluating spinal fusion in patients with cervical degenerative disk disease using ICBG compared with non-ICBG autograft or allograft or non-ICBG autograft compared with allograft in the cervical spine. Radiographic fusion, patient-reported outcomes, and functional outcomes were the primary outcomes of interest. Adverse events were evaluated for safety. The search identified 13 comparative studies that met our inclusion criteria: 2 prospective cohort studies and 11 retrospective cohort studies. Twelve cohort studies compared allograft with ICBG autograft during anterior cervical fusion and demonstrated with a low evidence level of support that there are no differences in fusion percentages, pain scores, or functional results. There was insufficient evidence comparing patients receiving allograft with non-ICBG autograft for fusion, pain, revision, and functional and safety outcomes. No publications directly comparing non-ICBG autograft with ICBG were found. Although the available literature suggests ICBG and allograft may have similar effectiveness in terms of fusion rates, pain scores, and functional outcomes following anterior cervical fusion, there are too many limitations in the available literature to draw any significant conclusions. No individual study provided greater than class III evidence, and when evaluating the overall body of literature, no conclusion had better than low evidence support. A prospective randomized trial with adequate sample size to

  17. Effects of implanted Doppler flowmeters on femoral vein autografts.

    PubMed Central

    Michie, D D; Cowan, D F; Cain, C P; Bell, C C

    1976-01-01

    Thirteen femoral vein autografts were placed into the corresponding ipsilateral femoral arteries of 8 mongrel dogs. Cuff-type Doppler (ultrasonic) flowmeters were placed around six of the grafts. None of the vessels thrombosed. Blood flow velocities were measured in all vessels up until the time of sacrifice (mean 95 +/- 5 days after surgery) or accidental death (one dog, 49 days after surgery). The only case of graft failure was attributed to infection at the flowmeter site. With this single exception, the vein grafts exhibited uniformity in histological appearance from dog to dog. These data suggest that implantation of properly designed Doppler flow transducers may have clinical applications. This technique permits continuous or intermittent assessment of blood flow characteristics through a graft without additional trauma or cost to the patient. It is free of the many inherent disadvantages of chronically implanted electromagnetic flowmeters and may negate the need in some instances for followup angiographic studies. Images Fig. 1. Fig. 2. Fig. 3. PMID:130843

  18. The superiority of the autografts inactivated by high hydrostatic pressure to decellularized allografts in a porcine model.

    PubMed

    Morimoto, Naoki; Mahara, Atsushi; Jinno, Chizuru; Ogawa, Mami; Kakudo, Natsuko; Suzuki, Shigehiko; Fujisato, Toshia; Kusumoto, Kenji; Yamaoka, Tetsuji

    2017-11-01

    We are developing a novel skin regeneration therapy in which the inactivation of nevus tissue via high hydrostatic pressure (HHP) is used in the reconstruction of the dermis in combination with a cultured epidermal autograft. In this study, we used a porcine skin graft model to explore whether autologous skin including cellular debris inactivated by HHP or allogeneic skin decellularized by HHP is better for dermal reconstruction. Grafts (n = 6) were prepared for five groups each: autologous skin without pressurization group (control group), autologous skin inactivated by 200 MPa group, autologous skin inactivated by 1000 MPa group, allogeneic skin decellularized by 200 MPa group, and allogeneic skin decellularized by 1000 MPa group. All of the grafts at 1, 4, and 12 weeks showed complete engraftment macroscopically. The mean areas of the grafts of the control group (p < 0.01) and autologous 200 MPa group (p < 0.01) were larger than that of the allogeneic 1000 MPa group at four weeks after implantation. The thickness of the control group and autologous 200 MPa group was comparable, and that of the autologous 200 MPa group was significantly thicker than that of the allogeneic 200 MPa group (p < 0.01). This suggests that the autologous dermis was superior to the allogeneic decellularized dermis as a skin graft, and that HHP at 200 MPa provided a better outcome than HHP at 1000 MPa. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2653-2661, 2017. © 2016 Wiley Periodicals, Inc.

  19. Functional characterization of optimized acellular peripheral nerve graft in a rat sciatic nerve injury model.

    PubMed

    Nagao, Ryan J; Lundy, Scott; Khaing, Zin Z; Schmidt, Christine E

    2011-07-01

    Acellular grafts are a viable option for use in nerve reconstruction surgeries. Recently, our lab created a novel optimized decellularization procedure that removes immunological material while leaving the majority of the extracellular matrix structure intact. The optimized acellular (OA) graft has been shown to elicit an immune response equal to or less than that elicited by the isograft, the analog of the autograft in the rat model. We investigated the performance of the OA graft to provide functional recovery in a long-term study. We performed a long-term functional regeneration evaluation study using the sciatic functional index to quantify recovery of Lewis rats at regular time intervals for up to 52 weeks after graft implantation following 1 cm sciatic nerve resection. OA grafts were compared against other decellularized methods (Sondell treatment and thermal decellularization), as well as the isograft and primary neurorrhaphy. The OA graft supported comparable functional recovery to the isograft and superior regeneration to thermal and Sondell decellularization methods. Furthermore, the OA graft promoted early recovery to a greater degree compared to acellular grafts obtained using either the thermal or the Sondell methods. Equivalent functional recovery to the isograft suggests that the OA nerve graft may be a future clinical alternative to the current autologous tissue graft.

  20. Vascularization of conjunctival autografts in pterygium surgery: comparison of fibrin glue with sutures.

    PubMed

    Küçükerdönmez, Cem; Karalezli, Aylin; Zengin, Mehmet Ozgur; Akova, Yonca Aydin

    2014-01-01

    To monitor the development of graft vascularization after pterygium excision with conjunctival autograft transplantation (CAT) using indocyanine green angiography (ICGA) and to compare the graft vascularization between 2 different fixation techniques (fibrin glue and sutures). A total of 26 eyes of 26 patients with primary pterygium were randomly assigned after pterygium excision as having either fibrin glue (13 eyes) or Vicryl sutures (13 eyes) for CAT. Anterior segment ICGA findings were evaluated postoperatively at 1, 7, and 15 days and the percentages of graft vascularization in both groups were compared using pixel analysis software program. The mean ± SD age of patients in the suture and fibrin glue groups was 52.1 ± 12.7 years and 57.1 ± 9.82 years, respectively. There was no statistically significant difference between the groups regarding age, sex, or follow-up (p<0.05 for all). Also, the mean intraoperative defect size was not significantly different between the groups, which was measured as 20.11 ± 10.44 mm2 in the suture group and 23.44 ± 12.34 mm2 in the fibrin glue group (p = 0.343). The mean percentage of vascularized graft area at postoperative day 1 and 7 was 18.1 ± 7.8% and 25.3 ± 8.6% in the suture group and 34.8 ± 10.2% and 66.1 ± 17.8% in the fibrin glue group. The difference between the groups was statistically significant (p<0.01 for both). At postoperative day 15, all grafts were 100% perfused in both groups. Fibrin glue fixation of conjunctival autografts led to more vascularization in the early postoperative period than suture fixated grafts, which in turn may have significance in terms of graft health and pterygium recurrence.

  1. When the tendon autograft is dropped accidently on the floor: A study about bacterial contamination and antiseptic efficacy.

    PubMed

    Barbier, O; Danis, J; Versier, G; Ollat, D

    2015-10-01

    Inadvertent contamination of the autograft can occur during anterior cruciate ligament (ACL) reconstruction if the autograft is dropped on the floor during surgery. A study was undertaken to determine the incidence of contamination when a graft is dropped on the operating room floor and the efficacy of antimicrobial solutions to decontaminate it. Samples from 25 patients undergoing ACL reconstruction with a hamstring tendon were sectioned and dropped onto the floor. Cultures were taken after immersion in antiseptic solutions (a chlorhexidine gluconate solution (group 1), a povidone-iodine solution (group 2), and a sodium hypochlorite solution (group 3)). A fourth piece (group 0) was cultured without being exposed to any solution. Cultures of a floor swab were taken at the same time. The floor swab cultures were positive in 96% of cases. The rate of contamination was 40% in group 0, 8% in group 1, 4% in group 2, and 16% in group 3. There was a significant difference between groups 1 and 2 and group 0 (p<0.05) but not between groups 3 and 0. Immersing a graft dropped on the floor during surgery in a chlorhexidine gluconate solution or povidone-iodine solution significantly reduces contamination of the graft. Soaking of the hamstring autograft in one of these solutions is recommended in the case of inadvertent contamination. Laboratory investigation (level 2). Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Accidental ovarian autograft after a laparoscopic surgery: case report.

    PubMed

    Marconi, G; Quintana, R; Rueda-Leverone, N G; Vighi, S

    1997-08-01

    To report an autograft of ovarian tissue in the incision of the surgical trocar during laparoscopic surgery and to assess the potentiality of grafting of ovarian parenchyma in nonpelvic tissue in humans. A case report. Instituto de Fertilidad y Ginecología de Buenos Aires (IFER), Buenos Aires, Argentina. Infertile patient undergoing surgery due to an endometriotic cyst of the left ovary. Laparoscopic cystectomy. Accidental retention of a portion of the capsule and adjacent ovarian tissue of the endometrioma in SC cellular tissue. Months after surgery, a SC tumor was formed under the surgical incision. It was subsequently excised. Observation of tumor growth during menstrual cycles and ovulation induction; anatomopathologic study of the tissue after its extirpation. The tumor grew spontaneously in the periovulatory period and during treatments of ovulation induction. The anatomopathologic report of the tumor, removed 15 months after the first surgery, revealed functioning ovarian tissue with vessels of neoformation. This is the first description of autografted ovarian tissue in humans. We describe that the ovary can maintain its ovulatory function even in the absence of its pedicel. Also, we suggest that extirpation of surgical material through the incision of the trocar is not recommended, as the possibility of "sowing" or of autografts may occur.

  3. rhBMP-2 (ACS and CRM formulations) overcomes pseudarthrosis in a New Zealand white rabbit posterolateral fusion model.

    PubMed

    Lawrence, James P; Waked, Walid; Gillon, Thomas J; White, Andrew P; Spock, Christopher R; Biswas, Debdut; Rosenberger, Patricia; Troiano, Nancy; Albert, Todd J; Grauer, Jonathan N

    2007-05-15

    The study design consisted of a New Zealand white rabbit model of pseudarthrosis repair. Study groups consisting of no graft, autograft, or recombinant human bone morphogenetic protein-2 (rhBMP-2) with absorbable collagen sponge (ACS) or compression resistant matrix (CRM) were evaluated. To evaluate the relative efficacy of bone graft materials (autograft, ACS, and CRM). rhBMP-2 has been shown to have a 100% fusion rate in a primary rabbit fusion model, even in the presence of nicotine, which is known to inhibit fusion. Seventy-two New Zealand white rabbits underwent posterolateral lumbar fusion with iliac crest autograft. To establish pseudarthroses, nicotine was administered to all animals. At 5 weeks, the spines were explored and all pseudarthroses were redecorticated and implanted with no graft, autograft, rhBMP-2/ACS, or rhBMP-2/CRM. At 10 weeks, fusions were assessed by manual palpation and histology. Eight rabbits (11%) were lost to complications. At 5 weeks, 66 (97%) had pseudarthroses. At 10 weeks, attempted pseudarthrosis repairs were fused in 1 of 16 of no graft rabbits (6%), 5 of 17 autograft rabbits (29%), and 31 of 31 rhBMP-2 rabbits (with ACS or CRM) (100%). Histologic analysis demonstrated more mature bone formation in the rhBMP-2 groups. The 2 rhBMP-2 formulations led to significantly higher fusion rates and histologic bone formation than no graft and autograft controls in this pseudarthrosis repair model.

  4. A mechanical argument for the differential performance of coronary artery grafts.

    PubMed

    Prim, David A; Zhou, Boran; Hartstone-Rose, Adam; Uline, Mark J; Shazly, Tarek; Eberth, John F

    2016-02-01

    Coronary artery bypass grafting (CABG) acutely disturbs the homeostatic state of the transplanted vessel making retention of graft patency dependent on chronic remodeling processes. The time course and extent to which remodeling restores vessel homeostasis will depend, in part, on the nature and magnitude of the mechanical disturbances induced upon transplantation. In this investigation, biaxial mechanical testing and histology were performed on the porcine left anterior descending artery (LAD) and analogs of common autografts, including the internal thoracic artery (ITA), radial artery (RA), great saphenous vein (GSV) and lateral saphenous vein (LSV). Experimental data were used to quantify the parameters of a structure-based constitutive model enabling prediction of the acute vessel mechanical response pre-transplantation and under coronary loading conditions. A novel metric Ξ was developed to quantify mechanical differences between each graft vessel in situ and the LAD in situ, while a second metric Ω compares the graft vessels in situ to their state under coronary loading. The relative values of these metrics among candidate autograft sources are consistent with vessel-specific variations in CABG clinical success rates with the ITA as the superior and GSV the inferior graft choices based on mechanical performance. This approach can be used to evaluate other candidate tissues for grafting or to aid in the development of synthetic and tissue engineered alternatives. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Long-Term Outcomes of Anterior Cruciate Ligament Reconstruction Using Either Synthetics With Remnant Preservation or Hamstring Autografts: A 10-Year Longitudinal Study.

    PubMed

    Chen, Tianwu; Zhang, Peng; Chen, Jiwu; Hua, Yinghui; Chen, Shiyi

    2017-10-01

    The optimal graft choice of anterior cruciate ligament (ACL) reconstruction remains controversial. To compare the outcomes, especially the long-term cumulative failure rate, of ACL reconstruction using either synthetics with remnant preservation or hamstring autografts (4-strand semitendinosus and gracilis tendons). Cohort study; Level of evidence, 2. A total of 133 patients who underwent ACL reconstruction (synthetics: n = 43; hamstring autografts: n = 90) between July 2004 and December 2007 were included. Questionnaires (Tegner activity scale, Lysholm knee scale, and International Knee Documentation Committee [IKDC] subjective form) were completed preoperatively and at 6 months, 1 year, 5 years, and 10 years postoperatively. The Knee injury and Osteoarthritis Outcome Score (KOOS) was additionally applied at 10 years' follow-up. The physical examination was based on the 2000 IKDC form. The manual maximum side-to-side difference (KT-1000 arthrometer), single-hop test, thigh muscle atrophy, and joint degeneration (Kellgren and Lawrence classification) were evaluated. The Kaplan-Meier curve and log-rank test (Mantel-Cox, 95% CI) were used to compare graft survivorship. Ten years postoperatively, 111 patients were available, with 38 (88.4%) patients (mean age, 27.6 ± 9.3 years; 28 men) with synthetics and 73 (81.1%) patients (mean age, 28.6 ± 8.8 years; 64 men) with hamstring autografts. Among them, 104 patients (synthetics: n = 35 [81.4%]; hamstring autografts: n = 69 [76.7%]) completed subjective evaluations, and 89 patients (synthetics: n = 30 [69.8%]; hamstring autografts: n = 59 [65.6%]) completed objective evaluations. For hamstring autografts and synthetics, the cumulative failure rates were 8.2% and 7.9%, respectively, and the log-rank test demonstrated no significant difference between the 2 Kaplan-Meier survival curves ( P = .910). At 6 months postoperatively, for hamstring autografts and synthetics, the mean Lysholm score was 83.0 ± 7.8 and 88.1 ± 7

  6. Clinical study of cultured epithelial autografts in liquid suspension in severe burn patients.

    PubMed

    Yim, Haejun; Yang, Hyeong Tae; Cho, Yong Suk; Seo, Cheong Hoon; Lee, Boung Chul; Ko, Jang Hyu; Kwak, In Suk; Kim, Dohern; Hur, Jun; Kim, Jong Hyun; Chun, Wook

    2011-09-01

    We address the clinical application of the suspension type cultured epithelial autografts (CEAs), Keraheal™ (MCTT, Seoul, Korea), along with the effects, application method, merits and demerits thereof. From February 2007 to June 2010, 29 burn patients with extensive burns, participated in the suspension type of CEA clinical test. A widely meshed autograft (1:4-6 ratio) was applied to the wound bed and the suspension type CEA was sprayed with a Tissomat cell sprayer, followed by a Tissucol spray, a fibrin sealant. The patients' (men/women=26/3) median (interquartile ranges) age was 42 (30-49) years old, the burned TBSA was 55 (44-60) %, and the full thickness burn area was 40 (30-46.5) %. The area of Keraheal™ applied was 800 (400-1200) cm(2). The take rate was 96 (90.5-99) % and 100 (98.5-100) % at 2 and 4 weeks after treatment with Keraheal™, respectively. The Vancouver burn scar scale was 5 (4-6.5), 4 (3-6), and 3 (2-4) at 8, 12 and 24 weeks after the Keraheal™ application. Widely meshed autograft must be applied in massive burns but it's take rate is greatly reduced. The CEAs enhance the take rate of a wide meshed autograft in massive burns and allow for grafting wide meshed autograft together with acellular dermal matrix in some cases. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

  7. Epidermal culture and grafting. A brief review.

    PubMed

    Muehleman, C; Wise, R D

    1993-08-01

    In summary, technological advances in culturing epidermis for the purpose of grafting allow this approach in the treatment of cutaneous wounds. Certainly, full- and split-thickness autografts offer immediate availability and permanent wound coverage, but they also involve a large, painful donor site. Cultured epidermal autografts can provide permanent wound coverage, but the delay required for cultivation of confluent sheets of keratinocytes makes them somewhat less desirable. Both allografts and cultured allografts, on the other hand, are available for immediate use, but the possibility of infectious disease transmission may be a concern. In any case, all types of skin grafts function as biological dressings that promote the proliferation of the host's epidermis and, thus, facilitate the ability of the patient's skin to repair itself.

  8. An update-tissue engineered nerve grafts for the repair of peripheral nerve injuries.

    PubMed

    Patel, Nitesh P; Lyon, Kristopher A; Huang, Jason H

    2018-05-01

    Peripheral nerve injuries (PNI) are caused by a range of etiologies and result in a broad spectrum of disability. While nerve autografts are the current gold standard for the reconstruction of extensive nerve damage, the limited supply of autologous nerve and complications associated with harvesting nerve from a second surgical site has driven groups from multiple disciplines, including biomedical engineering, neurosurgery, plastic surgery, and orthopedic surgery, to develop a suitable or superior alternative to autografting. Over the last couple of decades, various types of scaffolds, such as acellular nerve grafts (ANGs), nerve guidance conduits, and non-nervous tissues, have been filled with Schwann cells, stem cells, and/or neurotrophic factors to develop tissue engineered nerve grafts (TENGs). Although these have shown promising effects on peripheral nerve regeneration in experimental models, the autograft has remained the gold standard for large nerve gaps. This review provides a discussion of recent advances in the development of TENGs and their efficacy in experimental models. Specifically, TENGs have been enhanced via incorporation of genetically engineered cells, methods to improve stem cell survival and differentiation, optimized delivery of neurotrophic factors via drug delivery systems (DDS), co-administration of platelet-rich plasma (PRP), and pretreatment with chondroitinase ABC (Ch-ABC). Other notable advancements include conduits that have been bioengineered to mimic native nerve structure via cell-derived extracellular matrix (ECM) deposition, and the development of transplantable living nervous tissue constructs from rat and human dorsal root ganglia (DRG) neurons. Grafts composed of non-nervous tissues, such as vein, artery, and muscle, will be briefly discussed.

  9. [Study on preparation of laser micropore porcine acellular dermal matrix combined with split-thickness autograft and its application in wound transplantation].

    PubMed

    Liang, Li-Ming; Chai, Ji-Ke; Yang, Hong-Ming; Feng, Rui; Yin, Hui-Nan; Li, Feng-Yu; Sun, Qiang

    2007-04-01

    To prepare a porcine acellular dermal matrix (PADM), and to optimize the interpore distance between PADM and co-grafted split-thickness autologous skin. Porcine skin was treated with trypsin/Triton X-100 to prepare an acellular dermal matrix. Micropores were produced on the PADM with a laser punch. The distance between micropores varied as 0.8 mm, 1.0 mm, 1.2 mm and 1.5 mm. Full-thickness defect wounds were created on the back of 144 SD rats. The rats were randomly divided into 6 groups as follows, with 24 rats in each group. Micropore groups I -IV: the wounds were grafted with PADM with micropores in four different intervals respectively, and covered with split-thickness autologous skin graft. Mesh group: the wounds were grafted with meshed PADM and split-thickness autograft. with simple split-thickness autografting. The gross observation of wound healing and histological observation were performed at 2, 4, 6 weeks after surgery. The wound healing rate and contraction rate were calculated. Two and four weeks after surgery, the wound healing rate in micropore groups I and II was lower than that in control group (P < 0.05), but no obvious difference was between micropore groups I , II and mesh group (P > 0.05) until 6 weeks after grafting( P <0.05). The wound contraction rate in micropore groups I and II ([(16.0 +/- 2.6)%, (15.1 +/- 2.4)%] was remarkably lower than that in control group 4 and 6 weeks after grafting (P < 0.05), and it was significantly lower than that in mesh group [(19.3 +/- 2.4)%] 6 weeks after surgery (P <0.05). Histological examination showed good epithelization, regularly arranged collagenous fibers, and integral structure of basement membrane. Laser micropore PADM (0.8 mm or 1.0 mm in distance) grafting in combination with split-thickness autografting can improve the quality of wound healing. PADM with laser micropores in 1.0 mm distance is the best choice among them.

  10. Effect of Implanting a Soft Tissue Autograft in a Central-Third Patellar Tendon Defect: Biomechanical and Histological Comparisons

    PubMed Central

    Kinneberg, Kirsten R. C.; Galloway, Marc T.; Butler, David L.; Shearn, Jason T.

    2011-01-01

    Previous studies by our laboratory have demonstrated that implanting a stiffer tissue engineered construct at surgery is positively correlated with repair tissue stiffness at 12 weeks. The objective of this study was to test this correlation by implanting a construct that matches normal tissue biomechanical properties. To do this, we utilized a soft tissue patellar tendon autograft to repair a central-third patellar tendon defect. Patellar tendon auto-graft repairs were contrasted against an unfilled defect repaired by natural healing (NH). We hypothesized that after 12 weeks, patellar tendon autograft repairs would have biomechanical properties superior to NH. Bilateral defects were established in the central-third patellar tendon of skeletally mature (one year old), female New Zealand White rabbits (n = 10). In one limb, the excised tissue, the patellar tendon autograft, was sutured into the defect site. In the contralateral limb, the defect was left empty (natural healing). After 12 weeks of recovery, the animals were euthanized and their limbs were dedicated to bio-mechanical (n = 7) or histological (n = 3) evaluations. Only stiffness was improved by treatment with patellar tendon autograft relative to natural healing (p = 0.009). Additionally, neither the patellar tendon autograft nor natural healing repairs regenerated a normal zonal insertion site between the tendon and bone. Immunohistochemical staining for collagen type II demonstrated that fibrocartilage-like tissue was regenerated at the tendon-bone interface for both repairs. However, the tissue was disorganized. Insufficient tissue integration at the tendon-to-bone junction led to repair tissue failure at the insertion site during testing. It is important to re-establish the tendon-to-bone insertion site because it provides joint stability and enables force transmission from muscle to tendon and subsequent loading of the tendon. Without loading, tendon mechanical properties

  11. Endoscopic mucosal autograft for treating esophageal caustic strictures: preliminary human experience.

    PubMed

    He, Kexin; Zhao, Lili; Bu, Shoushan; Liu, Li; Wang, Xiang; Wang, Min; Fan, Zhining

    2018-06-11

     Esophageal caustic stricture is a stubborn disease and postoperative restenosis limits the clinical efficacy of endoscopic dilation. Autologous mucosal grafts have been successfully applied in the treatment of urethral stricture and in the prevention of stricture after extensive mucosal resection. We aimed to use mucosal autografting performed endoscopically to treat refractory esophageal stricture. METHODS : Three patients with intractable corrosive esophageal stricture were treated endoscopically by combining dilation with autologous mucosal transplantation. RESULTS : All procedures were successful with no severe complications. Mucosal regeneration was shown at the transplanted segments. One patient was able to maintain a normal diet with complete remission after 1 year of follow-up. Intraluminal stenosis and dysphagia were significantly improved in another two patients. CONCLUSIONS : Mucosal autografting can achieve esophageal re-epithelialization, inhibit undesired fibrosis, prevent restenosis, and promote functional regeneration. © Georg Thieme Verlag KG Stuttgart · New York.

  12. Application of Resorbable Poly(Lactide-co-Glycolide) with Entangled Hyaluronic Acid as an Autograft Extender for Posterolateral Intertransverse Lumbar Fusion in Rabbits

    PubMed Central

    Oliver, Rema A.; Gage, Gary; Yu, Yan; Bell, David; Bellemore, Jeremy; Adkisson, Huston Davis

    2011-01-01

    Facilitating fusion between bony segments in a reliable and reproducible manner using a synthetic bone graft material has a number of benefits for the surgeon as well as the patient. Although autograft remains the gold standard, associated comorbidities continue to drive the development of new biomaterials for use in spinal fusion. The ability of autograft alone and autograft combined with a radiolucent biomaterial composed of resorbable osteoconductive poly(lactide-co-glycolide) with entangled hyaluronic acid to facilitate fusion was examined in a single-level noninstrumented posterolateral intertransverse lumbar fusion model in New Zealand White rabbits. Progressive bone formation was demonstrated radiographically for the extender group (synthetic biomaterial plus autograft) between 3 and 6 months. Computed tomography revealed a new cortical shell in the fusion mass at 3 and 6 months for both study groups. Tensile testing at 6 months demonstrated that the quality of bone formed between the intertransverse space was equivalent for both study groups. Histologic evaluation of the fusion mass revealed new bone on and adjacent to the transverse processes with the synthetic biomaterial group that extended laterally, supporting the osteoconductive nature of the material. Histological evidence of endochondral bone growth in the intertransverse space was observed for the autograft plus synthetic biomaterial group. Bone remodeling, new marrow spaces, and peripheral cortices were observed for each study group at 3 months that matured by 6 months. These findings support the use of a radiolucent biosynthetic material comprising poly(lactide-co-glycolide) with integrated hyaluronic acid as an autograft extender for lumbar intertransverse fusion. PMID:20712417

  13. The reamer-irrigator-aspirator as a device for harvesting bone graft compared with iliac crest bone graft: union rates and complications.

    PubMed

    Dawson, John; Kiner, Dirk; Gardner, Warren; Swafford, Rachel; Nowotarski, Peter J

    2014-10-01

    This study was performed to compare patient outcomes after Reamer-Irrigator-Aspirator (RIA)-harvested bone grafting with the current gold standard, either anterior or posterior iliac crest bone graft (ICBG). Prospective randomized controlled trial. Multicenter study at 3 geographically separate Level 1 trauma centers. One hundred thirty-three patients with nonunion or posttraumatic segmental bone defect requiring operative intervention. Patients were prospectively randomized to receive ICBG or RIA autograft. Supplemental internal fixation was performed per surgeon preference. Operative data included amount of graft, time of harvest, and associated surgical costs. The Short Musculoskeletal Functional Assessment and the Visual Analog Scale were used to document baseline and postoperative function and pain. Clinical and radiographic union was the defined end point; patients considered to have failed treatment if they either developed an infection requiring operative treatment or had a persistent nonunion of the grafted extremity. One hundred thirteen of the 133 enrolled patients were followed until union and included in the final analysis. Intraoperative data showed anterior ICBG to yield 20.7 ± 12.8 (5-60) cm of autograft with an average harvest time of 33.2 ± 16.2 minutes, posterior ICBG yielded 36.1 ± 21.3 (20-100) cm of autograft in 40.6 ± 11.2 minutes, and RIA yielded 37.7 ± 12.9 (5-90) cm in 29.4 ± 15.1 minutes. Anterior ICBG produced significantly less bone graft than either RIA or posterior ICBG (P < 0.001). The RIA harvest was completed in significantly less operative time compared with posterior ICBG (P = 0.005). At $738, the RIA setup was considerably more expensive than the ∼$100 cost of a bone graft tray; however, when compared with posterior ICBG, the longer operative time required for a posterior harvest came at an additional incremental cost of $990-1880, making RIA the less expensive option. Patients were followed for an average of 56.9 ± 42

  14. Osteochondral Autograft from the Ipsilateral Femoral Head by Surgical Dislocation for Treatment of Femoral Head Fracture Dislocation: A Case Report.

    PubMed

    Won, Yougun; Lee, Gi Soo; Kim, Sang Bum; Kim, Sun Joong; Yang, Kyu Hyun

    2016-11-01

    As anatomical reduction of the articular surface of femoral head fractures and restoration of damaged cartilage are essential for good long-term results, many treatment options have been suggested, including fixation of the fracture using various surgical exposures and implants, as well as arthroscopic irrigation and debridement, bone marrow stimulating techniques, osteochondral allograft, autograft, and autogenous chondrocyte implantation. We report a case of osteochondral autograft harvested from its own femoral articular surface through surgical hip dislocation. The osteochondral graft was harvested from the inferior non-weight-bearing articular surface and grafted to the osteochondral defect. One year later, the clinical and radiological results were good, without the collapse of the femoral head or arthritic change. This procedure introduced in our case is considered convenient and able to lessen surgical time without morbidity of the donor site associated with the harvest.

  15. Methods for the preparation of an autologous serum-free cultured epidermis and for autografting applications.

    PubMed

    Wille, John J; Burdge, Jeremy J; Park, Jong Y

    2014-01-01

    Cell culture techniques for producing a three-dimensional autologous epidermal autograft (cultured epidermal autograft) suitable for tissue grafting and wound healing procedures are described. This chapter commences with surgical biopsy of patient's skin tissue, further reduction of skin tissues to keratinocyte cells by enzymatic treatment, and recovery of viable adult keratinocytes in a new balanced buffered salt media supportive of the growth of clonally enriched isolated basal keratinocytes. Culture techniques required for the formation of a hole-free monolayer of undifferentiated basal keratinocytes without the use of an organotypic matrix substrate are accomplished with a specially designed nutrient basal media (HECK 109) that is a chemically defined and subsequent culture in this serum-free culture media supplemented with hormones and two human recombinant protein growth factors (EGF and IGF-1). Further culture techniques and media manipulations, including brief exposure to β-TGF to induce reversible G1-phase growth arrest, are followed by para-synchronous induction of a multilayered stratification and keratinizing epidermal differentiation, yielding a living three-dimensional epidermis formed entirely in cell culture. Protocols are listed for its enzymatic removal, floatation, and transfer for shipment to the clinic ready for surgical grafting to the self-same patient's debrided chronic leg ulcers. Recent clinical trial results have demonstrated the utility and efficacy of these grafts in forming durably healed chronic wounds.

  16. ACL reconstruction with hamstring tendon autograft and accelerated brace-free rehabilitation: a systematic review of clinical outcomes

    PubMed Central

    van Melick, Nicky; van Mourik, Jan B A; Reijman, Max; van Rhijn, Lodewijk W

    2018-01-01

    Objective To investigate the clinical outcomes after hamstring tendon autograft ACL reconstruction (ACLR) with accelerated, brace-free rehabilitation. Design Systematic review according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Data sources Embase, MEDLINE Ovid, Web of Science, Cochrane CENTRAL and Google scholar from 1 January 1974 to 31 January 2017. Eligibility criteria for selecting studies Study designs reporting outcomes in adults after arthroscopic, primary ACLR with hamstring autograft and accelerated, brace-free rehabilitation. Results Twenty-four studies were included in the review. The clinical outcomes after hamstring tendon autograft ACLR with accelerated brace-free rehabilitation were the following: (1) early start of open kinetic exercises at 4 weeks in a limited range of motion (ROM, 90°−45°) and progressive concentric and eccentric exercises from 12 weeks did not alter outcomes, (2) gender and age did not influence clinical outcomes, (3) anatomical reconstructions showed better results than non-anatomical reconstructions, (4) there was no difference between single-bundle and double-bundle reconstructions, (5) femoral and tibial tunnel widening occurred, (6) hamstring tendons regenerated after harvest and (7) biological knowledge did not support return to sports at 4–6 months. Conclusions After hamstring tendon autograft ACLR with accelerated brace-free rehabilitation, clinical outcome is similar after single-bundle and double-bundle ACLR. Early start of open kinetic exercises at 4 weeks in a limited ROM (90°−45°) and progressive concentric and eccentric exercises from 12 weeks postsurgery do not alter clinical outcome. Further research should focus on achievement of best balance between graft loading and graft healing in the various rehabilitation phases after ACLR as well as on validated, criterion-based assessments for safe return to sports. Level of evidence Level 2b; therapeutic outcome studies

  17. Long-term retrospective study on the placement of the cementless acetabular cup and clinical outcomes in patients undergoing femoral head autografting for hip dysplasia and total hip arthroplasty.

    PubMed

    Ozden, Vahit Emre; Dikmen, Goksel; Beksac, Burak; Tozun, Ismail Remzi

    2018-05-01

    Placement of acetabular cup in the dysplastic hip is a challenging procedure. Using bulk femoral head autograft to increase the bony coverage of the cup is one of the techniques, which have been described. The impact of cup position on cup and autograft survival is a controversial issue. We aimed to determine whether the position of cementless acetabular cup used in conjunction with femoral head autograft in dysplastic hips affected the autograft-host incorporation with its final radiographic appearance and the cup survivorship into the second decade. Thirty-eight dysplastic hips with varying Crowe types in 31 patients (30 women and one man) were included. The mean age was 47 years (range, 29-64 years) and the mean follow-up was 20.3 years (range, 14.8-25.9 years). The initial postoperative and final radiographs were evaluated. The survival rate of the cups was analysed using Kaplan-Meier statistics and the log-rank test. Multivariate analysis was used to evaluate the effect of variables (Crowe type, radiographic initial host bone coverage over the cup and position of the cup) on survivorship. The acetabular cups were positioned anatomical in 27/38 hips according to Ranawat measurement technique. Trabecular bridging at graft-host interface was seen in all cases at an average 22.1 months. Neither acetabular cup position nor initial host bone coverage over acetabular cup less than 50% had any significant effect on either cup survival or final radiographic appearance of the graft. The 20-year cup survival rate without aseptic revision was 66% (95 CI, 52%-84%). No revision was performed due to graft resorption. Twenty-year survival rate of the cementless cup combination with femoral head autograft showed no significant differences whether it was placed at high or anatomic hip centre. The final radiographic appearance of the autograft was not affected from either the cup location or the initial radiographic horizontal host bone coverage. Copyright © 2018 The Japanese

  18. THE VASCULAR PATHOPHYSIOLOGY OF AN IRRADIATED GRAFT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rubin, P.; Casarett, G.; Grise, J.W.

    1960-06-01

    The difference in the vascularization of grafted and normal skin forms a reasonable basis for explaining the differences in the radiation reactions of these structures. The radioisotope half time of disappearance following subcutaneous injection is an index of vascular integrity of the graft and serves as a parameter to predict its radioresponsiveness. In developing a concept of the spectrum of reactions of grafted skin to ionizing irradiation, knowledge of the radiopathologic changes in capillaries must be utilized with knowledge of the histophysiology of the vascularity of an autograft. (auth)

  19. Increased Risk of Revision After Anterior Cruciate Ligament Reconstruction With Bone-Patellar Tendon-Bone Allografts Compared With Autografts.

    PubMed

    Maletis, Gregory B; Chen, Jason; Inacio, Maria C S; Love, Rebecca M; Funahashi, Tadashi T

    2017-05-01

    The use of allograft tissue for anterior cruciate ligament reconstruction (ACLR) remains controversial. To compare the risk of aseptic revision between bone-patellar tendon-bone (BPTB) autografts and BPTB allografts. Cohort study; Level of evidence, 2. A retrospective cohort study of prospectively collected data was conducted using the Kaiser Permanente ACLR Registry. A cohort of patients who underwent primary unilateral ACLR with BPTB autografts and BPTB allografts was identified. Aseptic revision was the endpoint. The type of graft and allograft processing method (nonprocessed, <1.8-Mrad, and ≥1.8-Mrad irradiation) were the exposures of interest evaluated. Age (≤21 and ≥22 years) was evaluated as an effect modifier. Analyses were adjusted for age, sex, and race. Kaplan-Meier curves and Cox proportional hazards models were employed. Hazard ratios (HRs) and 95% CIs are provided. The BPTB cohort consisted of 5586 patients: 3783 (67.7%) were male, 2359 (42.2%) were white, 1029 (18.4%) had allografts (nonprocessed: 155; <1.8 Mrad: 525; ≥1.8 Mrad: 288), and 4557 (81.6%) had autografts. The median age was 34.9 years (interquartile range [IQR], 25.4-44.0) for allograft cases and 22.0 years (IQR, 17.6-30.0) for autograft cases. The estimated cumulative revision rate at 2 years was 4.1% (95% CI, 2.9%-5.9%) for allografts and 1.7% (95% CI, 1.3%-2.2%) for autografts. BPTB allografts had a significantly higher adjusted risk of revision than BPTB autografts (HR, 4.54; 95% CI, 3.03-6.79; P < .001). This higher risk of revision was consistent with all allograft processing methods when compared with autografts and was also consistently higher in patients with allografts regardless of age. When BPTB allograft tissue was used for ACLR, an overall 4.54 times adjusted higher risk of revision was observed compared with surgery performed with a BPTB autograft. Whether the tissue was irradiated with either high- or low-dose radiation, chemically processed, or not processed at

  20. Optimal size of pterygium excision for limbal conjunctival autograft using fibrin glue in primary pterygia.

    PubMed

    Hwang, Ho Sik; Cho, Kyong Jin; Rand, Gabriel; Chuck, Roy S; Kwon, Ji Won

    2018-06-07

    In our study we describe a method that optimizes size of excision and autografting for primary pterygia along with the use of intraoperative MMC and fibrin glue. Our objective is to propose a simple, optimizedpterygium surgical technique with excellent aesthetic outcomes and low rates of recurrence and otheradverse events. Retrospective chart review of 78 consecutive patients with stage III primary pterygia who underwent an optimal excision technique by three experienced surgeons. The technique consisted of removal of the pterygium head, excision of the pterygium body and Tenon's layer limited in proportion to the length of the head, application of intraoperative mitomycin C to the defect, harvest of superior bulbar limbal conjunctival graft, adherence of graft with fibrin glue. Outcomes included operative time, follow up period, pterygium recurrence, occurrences of incorrectly sized grafts, and other complications. All patients were followed up for more than a year. Of the 78 patients, there were 2 cases of pterygium recurrence (2.6%). There was one case of wound dehiscence secondary to small-sized donor conjunctivaand one case of over-sized donor conjunctiva, neither of which required surgical correction. There were no toxic complications associated with the use of mitomycin C. Correlating the excision of the pterygium body and underlying Tenon's layer to the length of the pterygium head, along with the use intraoperative mitomycin C, limbal conjunctival autografting, and fibrin adhesionresulted in excellent outcomes with a low rate of recurrence for primary pterygia.

  1. Photoacoustic detection of neovascularities in skin graft

    NASA Astrophysics Data System (ADS)

    Yamazaki, Mutsuo; Sato, Shunichi; Saitoh, Daizo; Ishihara, Miya; Okada, Yoshiaki; Ashida, Hiroshi; Obara, Minoru

    2005-04-01

    We previously proposed a new method for monitoring adhesion of skin graft by measuring photoacoustic (PA) signal originated from the neovascularities. In this study, immunohistochemical staining (IHC) with CD31 antibody was performed for grafted skin tissue to observe neovascularity, and the results were compared with PA signals. We also used a laser Doppler imaging (LDI) to observe blood flow in the grafted skin, and sensitivity of PA measurement and that of LDI were compared. In rat autograft models, PA signals were measured for the grafted skin at postgrafting times of 0-48 h. At 6 h postgrafting, PA signal was observed in the skin depth region of 500-600 mm, while the results of IHC showed that angiogenesis occurred at the depth of about 600 mm. Depths at which PA signal and angiogenesis were observed decreased with postgrafting time. These indicate that the PA signal observed at 6 h postgrafting originated from the neovascularities in the skin graft. Results of LDI showed no blood-originated signal before 48 h postgrafting. These findings suggest that PA measurement is effective in monitoring the adhesion of skin graft in early stage after transplantation.

  2. Burns (Part 2). Tops and flops using cultured epithelial autografts in children.

    PubMed

    Meuli, M; Raghunath, M

    1997-09-01

    The goal of this article is to review the status of cultured epithelial autografts in clinical practice with particular focus on the pediatric subset of patients. The current indications include massive deep burns (>60 - 70% total body surface area), resurfacing-type postburn scar revisions, and skin defect coverage following excision of large skin lesions like giant nevi. Although this method can be lifesaving for massively burned patients, and although excellent functional and cosmetic results may be obtained under ideal circumstances, formidable problems continue to exist. Take is inconsistent, cultured grafts are extremely susceptible to infection, and skin breakdown during the first months post grafting may occur due to mechanical instability of the regenerating skin. It may take one more decade of concerted research, jointly performed by clinicians and tissue culture technology experts in order to fabricate more skin-like grafts which are robust, reliable, and less expensive. Then, "cultured skin" will conquer the world and benefit countless patients.

  3. Immediate post-operative pain in anterior cruciate ligament reconstruction surgery with bone patellar tendon bone graft versus hamstring graft.

    PubMed

    Gupta, Ravi; Kapoor, Dheeraj; Kapoor, Love; Malhotra, Anubhav; Masih, Gladson David; Kapoor, Anil; Joshi, Shweta

    2016-06-08

    Pain in the immediate post-operative period after anterior cruciate ligament (ACL) surgery, apart from an unpleasant experience for the patient, can act as a barrier for static quadriceps contractions and optimum execution of the initial rehabilitation protocol resulting in slow recovery and a later return to full function for a sportsperson. There is no report in the literature comparing pain in the immediate post-operative period after using the two most widely used autografts, bone patellar tendon bone (BPTB) graft and hamstring graft. The present study compared the visual analogue scale (VAS) pain score in the immediate post-operative period after arthroscopic ACL reconstruction with the BPTB and hamstring autografts. Both groups consisted of 50 patients each. The mean age of the BPTB and hamstring cohorts was 26.9 ± 7.3 years (age range 18-59 years) and 26.7 ± 9.0 years (age range 17-52 years), respectively. Unpaired t test was applied to compare pain scores between the BPTB and hamstring cohorts. In the present study, patients in the BPTB cohort showed higher mean pain scores across all the post-operative time intervals except at 6 h. However, the difference in the mean VAS pain score at post-operative 6, 12,18, 24, 36 and 48 h in the two groups was statistically not significant (p value of 1, 0.665, 0.798, 0.377, 0.651 and 0.215 at 6, 12, 18, 24, 36 and 48 h, respectively). Our study concludes that the arthroscopic ACL reconstruction with BPTB autograft and hamstring autograft is associated with similar pain in the immediate post-operative period. As a result, aggressive physiotherapy regime is not affected by the type of graft being used for ACL reconstruction, as the pain scores in the immediate post-operative period are similar for both techniques. Clinical Trials Registry-India, CTRI/2016/01/006502.

  4. The influence of pterygium morphology on fibrin glue conjunctival autografting pterygium surgery.

    PubMed

    Sandra, Sekelj; Zeljka, Janjetovic; Zeljka, Vukovic Arar; Kristian, Samardzic; Ivana, Aric

    2014-02-01

    To evaluate the influence of pterygium morphology on the efficacy and safety of fibrin glue in pterygium surgery with conjunctival autografting. A prospective case series. During a period of 15 months, 45 patients (51 eyes) were recruited from the General Hospital for pterygium surgery. Seven eyes (13.73 %) were operated on for a recurrent pterygium. Autologous conjunctiva was harvested from the superior bulbar conjunctiva and fixed with fibrin glue. The pterygia were preoperatively divided into atrophic/grade 1 (n = 18; 35.29 %), intermediate/grade 2 (n = 22; 43.14 %) or fleshy/grade 3 (n = 11; 21.57 %) according to clinical morphology. Patients were evaluated for intraoperative and postoperative complications and recurrence rates. The success rate was defined by no pterygium recurrences. Patients with 2-year follow-ups were included in this study. Fifty-one patients (21 females/30 males) with a mean age of 60-65 years (range 24-87 years) took part in the study. All patients completed the study. No intraoperative complications were noted. Postsurgical complications included graft edema (n = 4; 7.8 %), graft hyperemia (n = 2; 3.8 %), and graft dislocation (n = 3; 5.9 %); these complications were transient. One graft unfastened completely (2 %) and five pterygium recurrences occurred (n = 5; 9.8 %). The overall success rate was 90 % after 2 years. In grade I group there were no recurrences, in grade 2 group there were two recurrences, and in grade 3 group there were three recurrences. There were significantly more recurrences in grade 3 group than in grade 2 group. There were more recurrences in both groups than in group 1 (60 vs 40 vs 0 % of all recurrences, p ≤ 0.05). The use of fibrin glue is a safe, easy and effective technique for attaching the conjunctival autograft in pterygium surgery. The morphology of pterygium influences recurrence rates, without significance for intraoperative and postoperative complications.

  5. Twenty-Year Outcome of a Longitudinal Prospective Evaluation of Isolated Endoscopic Anterior Cruciate Ligament Reconstruction With Patellar Tendon or Hamstring Autograft.

    PubMed

    Thompson, Simon Michael; Salmon, Lucy J; Waller, Alison; Linklater, James; Roe, Justin P; Pinczewski, Leo A

    2016-12-01

    Long-term prospective studies of isolated endoscopic anterior cruciate ligament (ACL) reconstruction are limited and may include confounding factors. This study aimed to compare the outcomes of isolated ACL reconstruction using the patellar tendon (PT) autograft and the hamstring (HT) autograft in 180 patients over 20 years. Cohort study; Level of evidence, 2. A total of 180 participants undergoing isolated ACL reconstruction between 1993 and 1994 were prospectively recruited. Evaluation was performed at 1, 2, 5, 7, 10, 15, and 20 years after surgery and included the International Knee Documentation Committee (IKDC) knee ligament evaluation with radiographic evaluation, KT-1000 arthrometer side-to-side difference, and subjective scores. Over 20 years, there were 16 patients (18%) and 9 patients (10%) with an ACL graft rupture in the HT and PT groups, respectively (P = .13). ACL graft rupture was associated with male sex (odds ratio [OR], 3.9; P = .007), nonideal tunnel position (OR, 3.6; P = .019), and age <18 years at the time of surgery (OR, 4.6; P = .003). The odds of a contralateral ACL rupture were increased in patients with the PT graft compared with patients with the HT graft (OR, 2.2; P = .02) and those aged <18 years at the time of surgery (OR, 3.4; P = .001). The mean IKDC scores at 20-year follow-up were 86 and 89 for the PT and HT groups, respectively (P = .18). At 20 years, 53% and 57% of the PT and HT groups participated in strenuous or very strenuous activities (P = .55), kneeling pain was present in 63% and 20% of the PT and HT groups (P = .018), and radiographic osteoarthritic change was found in 61% and 41% of the PT and HT groups (P = .008), respectively. Compared with patients who received the HT graft, patients who received the PT graft had significantly worse outcomes with regard to radiologically detectable osteoarthritis, kneeling pain, and contralateral ACL injury. At 20-year follow-up, both HT and PT autografts continued to provide good

  6. Preparation of laser micropore porcine acellular dermal matrix for skin graft: an experimental study.

    PubMed

    Chai, Jia-Ke; Liang, Li-Ming; Yang, Hong-Ming; Feng, Rui; Yin, Hui-Nan; Li, Feng-Yu; Sheng, Zhi-Yong

    2007-09-01

    In our previous study, we used composite grafts consisting of meshed porcine acellular dermal matrix (PADM) and thin split-thickness autologous epidermis to cover full thickness burn wounds in clinical practice. However, a certain degree of contraction might occur because the distribution of dermal matrix was not uniform in burn wound. In this study, we prepare a composite skin graft consisting of PADM with the aid of laser to improve the quality of healing of burn wound. PADM was prepared by the trypsin/Triton X-100 method. Micropores were produced on the PADM with a laser punch. The distance between micropores varied from 0.8, 1.0, 1.2 to 1.5mm. Full thickness defect wounds were created on the back of 144 SD rats. The rats were randomly divided into six groups: micropore groups I-IV in which the wound were grafted with PADM with micropores, in four different distances, respectively and split-thickness autograft; mesh group rats received meshed PADM graft and split-thickness autograft; control group received simple split-thickness autografting. The status of wound healing was histologically observed at regular time points after surgery. The wound healing rate and contraction rate were calculated. The wound healing rate in micropore groups I and II was not statistically different from that in control group, but was significantly higher than that in mesh group 6 weeks after grafting. The wound healing rate in micropore groups III and IV was lower than that in mesh and control groups 4 and 6 weeks after grafting. The wound contraction rate in micropore groups I and II was remarkably lower than that in control group 4 and 6 weeks after surgery and it was significantly much lower than that in mesh group 6 weeks after surgery. Histological examination revealed good epithelization, regularly arranged collagenous fibers and integral structure of basement membrane. Laser micropore PADM (0.8 or 1.0mm in distance) grafting in combination with split-thickness autografting can

  7. Quadriceps Tendon Autograft in Anterior Cruciate Ligament Reconstruction: A Systematic Review.

    PubMed

    Hurley, Eoghan T; Calvo-Gurry, Manuel; Withers, Dan; Farrington, Shane K; Moran, Ray; Moran, Cathal J

    2018-05-01

    To systematically review the current evidence to ascertain whether quadriceps tendon autograft (QT) is a viable option in anterior cruciate ligament reconstruction. A literature review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Cohort studies comparing QT with bone-patellar tendon-bone autograft (BPTB) or hamstring tendon autograft (HT) were included. Clinical outcomes were compared, with all statistical analyses performed using IBM SPSS Statistics for Windows, version 22.0, with P < .05 being considered statistically significant. We identified 15 clinical trials with 1,910 patients. In all included studies, QT resulted in lower rates of anterior knee pain than BPTB. There was no difference in the rate of graft rupture between QT and BPTB or HT in any of the studies reporting this. One study found that QT resulted in greater knee stability than BPTB, and another study found increased stability compared with HT. One study found that QT resulted in improved functional outcomes compared with BPTB, and another found improved outcomes compared with HT, but one study found worse outcomes compared with BPTB. Current literature suggests QT is a viable option in anterior cruciate ligament reconstruction, with published literature showing comparable knee stability, functional outcomes, donor-site morbidity, and rerupture rates compared with BPTB and HT. Level III, systematic review of Level I, II, and III studies. Copyright © 2018 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  8. An analysis of surgical and anaesthetic factors affecting skin graft viability in patients admitted to a Burns Intensive Care Unit.

    PubMed

    Isitt, Catherine E; McCloskey, Kayleigh A; Caballo, Alvaro; Sharma, Pranev; Williams, Andrew; Leon-Villapalos, Jorge; Vizcaychipi, Marcela P

    2016-01-01

    Skin graft failure is a recognised complication in the treatment of major burns. Little research to date has analysed the impact of the complex physiological management of burns patients on the success of skin grafting. We analysed surgical and anaesthetic variables to identify factors contributing to graft failure. Inclusion criteria were admission to our Burns Intensive Care Unit (BICU) between January 2009 and October 2013 with a major burn. After exclusion for death before hospital discharge or prior skin graft at a different hospital, 35 patients remained and were divided into those with successful autografts (n=16) and those with a failed autograft (n=19). For the purposes of this study, we defined poor autograft viability as requiring at least one additional skin graft to the same site. Logistic regression of variables was performed using SPSS (Version 22.0 IBMTM). Age, Sex, %Total Burn Surface Area or Belgian Outcome Burns Injury score did not significantly differ between groups. No differences were found in any surgical factor at logistic regression (graft site, harvest site, infection etc.). When all operations were analysed, the use of colloids was found to be significantly associated with graft failure (p=0.035, CI 95%) and this remained significant when only split thickness skin grafts (STSGs) and debridement operations were included (p=0.034, CI 95%). No differences were found in crystalloid use, intraoperative temperature, pre-operative haemoglobin and blood products or vasopressor use. This analysis highlights an independent association between colloids and graft failure which has not been previously documented.

  9. [Biomaterials for bone filling: comparisons between autograft, hydroxyapatite and one highly purified bovine xenograft].

    PubMed

    Chappard, D; Zhioua, A; Grizon, F; Basle, M F; Rebel, A

    1993-12-01

    Bone grafts are becoming increasingly common in orthopaedics, neurosurgery and periodontology. Twenty one New Zealand rabbits were used in the present study comparing several materials usable as bone substitutes. A 4.5 mm hole was drilled in the inner femoral condyles. Holes were filled with either an autograft (from the opposite condyle), an hydroxylapatite (Bioapatite), or a highly purified bovine xenograft (T650 Lubboc). Animals were sacrificed at 1, 3 and 6 months post implantation and a quantitative analysis of newly-formed bone volume (BNF/IV) and remaining biomaterials (BMAT/IV) was done. In addition, some holes were left unfilled and served as controls. At 6 months, there was no tendency for spontaneous repair in the control animals. The autografted animals have repaired their trabecular mass and architecture within the first month. Hydroxylapatite appeared unresorbed at six months and only thin and scanty new trabeculae were observed. The xenograft induced woven bone trabeculae formation on the first month. This was associated with resorption of the material by two multinucleated cell populations. At six months, the epiphyseal architecture was restored and the biomaterial has disappeared in most cases. Xenografts appear a promising alternative to autografts and allografts, whose infectious risks and ethical problems should always be borne in mind.

  10. Soft tissue grafting to improve implant esthetics

    PubMed Central

    Kassab, Moawia M

    2010-01-01

    Dental implants are becoming the treatment of choice to replace missing teeth, especially if the adjacent teeth are free of restorations. When minimal bone width is present, implant placement becomes a challenge and often resulting in recession and dehiscence around the implant that leads to subsequent gingival recession. To correct such defect, the author turned to soft tissue autografting and allografting to correct a buccal dehiscence around tooth #24 after a malpositioned implant placed by a different surgeon. A 25-year-old woman presented with the chief complaint of gingival recession and exposure of implant threads around tooth #24. The patient received three soft tissue grafting procedures to augment the gingival tissue. The first surgery included a connective tissue graft to increase the width of the keratinized gingival tissue. The second surgery included the use of autografting (connective tissue graft) to coronally position the soft tissue and achieve implant coverage. The third and final surgery included the use of allografting material Alloderm to increase and mask the implant from showing through the gingiva. Healing period was uneventful for the patient. After three surgical procedures, it appears that soft tissue grafting has increased the width and height of the gingiva surrounding the implant. The accomplished thickness of gingival tissue appeared to mask the showing of implant threads through the gingival tissue and allowed for achieving the desired esthetic that the patient desired. The aim of the study is to present a clinical case with soft tissue grafting procedures. PMID:23662087

  11. Histological evaluation of an impacted bone graft substitute composed of a combination of mineralized and demineralized allograft in a sheep vertebral bone defect.

    PubMed

    Fujishiro, Takaaki; Bauer, Thomas W; Kobayashi, Naomi; Kobayashi, Hideo; Sunwoo, Moon Hae; Seim, Howard B; Turner, A Simon

    2007-09-01

    Demineralized bone matrix (DBMs) preparations are a potential alternative or supplement to autogenous bone graft, but many DBMs have not been adequately tested in clinically relevant animal models. The aim of current study was to compare the efficacy of a new bone graft substitute composed of a combination of mineralized and demineralized allograft, along with hyaluronic acid (AFT Bone Void Filler) with several other bone graft materials in a sheep vertebral bone void model. A drilled defect in the sheep vertebral body was filled with either the new DBM preparation, calcium sulfate (OsteoSet), autologous bone graft, or left empty. The sheep were euthanized after 6 or 12 weeks, and the defects were examined by histology and quantitative histomorphometry. The morphometry data were analyzed by one-way analysis of variance with the post hoc Tukey-Kramer test or the Student's t-test. All of the bone defects in the AFT DBM preparation group showed good new bone formation with variable amounts of residual DBM and mineralized bone graft. The DBM preparation group at 12 weeks contained significantly more new bone than the defects treated with calcium sulfate or left empty (respectively, p < 0.05, p < 0.01). There was no significant difference between the DBM and autograft groups. No adverse inflammatory reactions were associated with any of the three graft materials. The AFT preparation of a mixture of mineralized and demineralized allograft appears to be an effective autograft substitute as tested in this sheep vertebral bone void model.

  12. Graft Diameter as a Predictor for Revision Anterior Cruciate Ligament Reconstruction and KOOS and EQ-5D Values: A Cohort Study From the Swedish National Knee Ligament Register Based on 2240 Patients.

    PubMed

    Snaebjörnsson, Thorkell; Hamrin Senorski, Eric; Ayeni, Olufemi R; Alentorn-Geli, Eduard; Krupic, Ferid; Norberg, Fredrik; Karlsson, Jón; Samuelsson, Kristian

    2017-07-01

    Anterior cruciate ligament (ACL) reconstruction (ACLR) using a hamstring tendon (HT) autograft is an effective and widespread method. Recent studies have identified a relationship between the graft diameter and revision ACLR. To evaluate the influence of the graft diameter on revision ACLR and patient-reported outcomes in patients undergoing primary ACLR using HT autografts. Cohort study; Level of evidence, 2. A prospective cohort study was conducted using the Swedish National Knee Ligament Register (SNKLR) involving all patients undergoing primary ACLR using HT autografts. Patients with graft failure who needed revision surgery (cases) were compared with patients not undergoing revision surgery (controls). The control group was matched for sex, age, and graft fixation method in a 3:1 ratio. Conditional logistic regression was performed to produce odds ratios and 95% CIs. Univariate linear regression analyses were performed for patient-related outcomes. The Knee injury and Osteoarthritis Outcome Score (KOOS) and EuroQol 5 dimensions questionnaire (EQ-5D) values were obtained. A total of 2240 patients were included in which there were 560 cases and 1680 controls. No significant differences between the cases and controls were found for sex (52.9% male), mean age (21.7 years), and femoral and tibial fixation. The mean graft diameter for the cases was 8.0 ± 0.74 mm and for the controls was 8.1 ± 0.76 mm. In the present cohort, the likelihood of revision surgery for every 0.5-mm increase in the HT autograft diameter between 7.0 and 10.0 mm was 0.86 (95% CI, 0.75-0.99; P = .03). Univariate linear regression analysis found no significant regression coefficient for the change in KOOS or EQ-5D values. In a large cohort of patients after primary ACLR with HT autografts, an increase in the graft diameter between 7.0 and 10.0 mm resulted in a 0.86 times lower likelihood of revision surgery with every 0.5-mm increase. This study provides further evidence of the importance of

  13. A hyaluronic acid membrane delivery system for cultured keratinocytes: clinical "take" rates in the porcine kerato-dermal model.

    PubMed

    Myers, S R; Grady, J; Soranzo, C; Sanders, R; Green, C; Leigh, I M; Navsaria, H A

    1997-01-01

    The clinical take rates of cultured keratinocyte autografts are poor on a full-thickness wound unless a dermal bed is provided. Even under these circumstances two important problems are the time delay in growing autografts and the fragility of the grafts. A laser-perforated hyaluronic acid membrane delivery system allows grafting at early confluence without requiring dispase digestion to release grafts from their culture dishes. We designed this study to investigate the influence of this membrane on clinical take rates in an established porcine kerato-dermal grafting model. The study demonstrated a significant reduction in take as a result of halving the keratinocyte seeding density onto the membrane. The take rates, however, of grafts grown on the membrane at half or full conventional seeding density and transplanted to a dermal wound bed were comparable, if not better, than those of keratinocyte sheet grafts.

  14. Development of the mechanical properties of engineered skin substitutes after grafting to full-thickness wounds.

    PubMed

    Sander, Edward A; Lynch, Kaari A; Boyce, Steven T

    2014-05-01

    Engineered skin substitutes (ESSs) have been reported to close full-thickness burn wounds but are subject to loss from mechanical shear due to their deficiencies in tensile strength and elasticity. Hypothetically, if the mechanical properties of ESS matched those of native skin, losses due to shear or fracture could be reduced. To consider modifications of the composition of ESS to improve homology with native skin, biomechanical analyses of the current composition of ESS were performed. ESSs consist of a degradable biopolymer scaffold of type I collagen and chondroitin-sulfate (CGS) that is populated sequentially with cultured human dermal fibroblasts (hF) and epidermal keratinocytes (hK). In the current study, the hydrated biopolymer scaffold (CGS), the scaffold populated with hF dermal skin substitute (DSS), or the complete ESS were evaluated mechanically for linear stiffness (N/mm), ultimate tensile load at failure (N), maximum extension at failure (mm), and energy absorbed up to the point of failure (N-mm). These biomechanical end points were also used to evaluate ESS at six weeks after grafting to full-thickness skin wounds in athymic mice and compared to murine autograft or excised murine skin. The data showed statistically significant differences (p <0.05) between ESS in vitro and after grafting for all four structural properties. Grafted ESS differed statistically from murine autograft with respect to maximum extension at failure, and from intact murine skin with respect to linear stiffness and maximum extension. These results demonstrate rapid changes in mechanical properties of ESS after grafting that are comparable to murine autograft. These values provide instruction for improvement of the biomechanical properties of ESS in vitro that may reduce clinical morbidity from graft loss.

  15. Fibrin glue versus sutures for conjunctival autografting in primary pterygium surgery.

    PubMed

    Romano, Vito; Cruciani, Mario; Conti, Luigi; Fontana, Luigi

    2016-12-02

    any re-growth of tissue from the area of excision across the limbus onto the cornea. The secondary outcomes were surgical time and complication rate. We graded the certainty of the evidence using GRADE. We included 14 RCTs conducted in Brazil, China, Egypt, India, Malaysia, New Zealand, Philippines, Saudi Arabia, Sweden and Turkey. The trials were published between 2004 and 2016, and were assessed as a mixture of unclear and low risk of bias with three studies at high risk of attrition bias. Only adults were enrolled in these studies.Using fibrin glue for the conjunctival autograft may result in less recurrence of pterygium compared with using sutures (risk ratio (RR) 0.47, 95% CI 0.27 to 0.82, 762 eyes, 12 RCTs; low-certainty evidence). If pterygium recurs after approximately 10 in every 100 surgeries with sutures, then using fibrin glue may result in approximately 5 fewer cases of recurrence in every 100 surgeries (95% CI 2 fewer to 7 fewer cases). Using fibrin glue may lead to more complications compared with sutures (RR 1.92; 95% CI 1.22 to 3.02, 11 RCTs, 673 eyes, low-certainty evidence). The most common complications reported were: graft dehiscence, graft retraction and granuloma. On average using fibrin glue may mean that surgery is quicker compared with suturing (mean difference (MD) -17.01 minutes 95% CI -20.56 to -13.46), 9 RCTs, 614 eyes, low-certainty evidence). The meta-analyses, conducted on people with pterygium in a hospital or outpatient setting, show fibrin glue may result in less recurrence and may take less time than sutures for fixing the conjunctival graft in place during pterygium surgery. There was low-certainty evidence to suggest a higher proportion of complications in the fibrin glue group.

  16. Multiscale mechanobiology of de novo bone generation, remodeling and adaptation of autograft in a common ovine femur model.

    PubMed

    Knothe Tate, Melissa L; Dolejs, Scott; McBride, Sarah H; Matthew Miller, R; Knothe, Ulf R

    2011-08-01

    The link between mechanics and biology in the generation and the adaptation of bone has been studied for more than a century in the context of skeletal development and fracture healing. However, the interplay between mechanics and biology in de novo generation of bone in postnatal defects as well as healing of morcellized bone graft or massive cortical bone autografts is less well understood. To address this, here we integrate insights from our previously published studies describing the mechanobiology on both de novo bone generation and graft healing in a common ovine femoral defect model. Studying these effects in a common experimental model provides a unique opportunity to elucidate factors conducive to harnessing the regenerative power of the periosteum, and ultimately, to provide mechanistic insights into the multiscale mechanobiology of bone generation, remodeling and adaptation. Taken together, the studies indicate that, as long as adequate, directional transport of cells and molecules can be insured (e.g. with periosteum in situ or a delivery device), biological factors intrinsic to the periosteum suffice to bridge critical sized bone defects, even in the absence of a patent blood supply. Furthermore, mechanical stimuli are crucial for the success of periosteal bone generation and bone graft healing. Interestingly, areas of highest periosteal strain around defects correlate with greatest amounts albeit not greatest mineralization of newly generated bone. This may indicate a role for convection enhanced transport of cells and molecules in modulation of tissue generation by pluripotent cells that ingress into the defect center, away from the periosteum and toward the surface of the intramedullary nail that fills the medullary cavity. These insights bring us much closer to understanding the mechanobiological environment and stimuli that stimulate the proliferation and differentiation of periosteum-derived progenitor cells and ultimately drive the generation of

  17. Visual outcome and efficacy of conjunctival autograft, harvested from the body of pterygium in pterygium excision.

    PubMed

    Bhandari, Vipul; Rao, Chandan Latha; Ganesh, Sri; Brar, Sheetal

    2015-01-01

    To evaluate the efficacy of conjunctival autograft after the pterygium excision with fibrin adhesive using conjunctiva over the pterygium. This prospective study included 25 eyes of 25 patients with a mean age of 40±10 years, who underwent the pterygium excision with conjunctival autograft derived from the body of the pterygium and attached using fibrin glue. The mean follow-up period was 6 months. On all postoperative visits, changes in uncorrected visual acuity, corrected distance visual acuity, astigmatism, complications, and the evidence of recurrence were recorded. At the end of mean follow-up, uncorrected visual acuity and corrected distance visual acuity improved by one or two lines in all eyes treated. Mean astigmatism reduced significantly from a preoperative value from 2.308D to 1.248D postoperatively (P<0.026). Minor postoperative complications such as congestion, chemosis, and subconjunctival hemorrhage were seen, which resolved with time. No major sight-threatening or graft-related complications were detected. There was no evidence of recurrence during a follow-up period of 6 months. Self-conjunctival autograft following the pterygium excision appears to be a feasible, safe, and effective alternative method for management of pterygium. It also preserves the superior conjunctiva for future surgeries. However, longer follow-up is required to study the long-term outcomes, especially the incidence of recurrence.

  18. Allogeneic versus autologous derived cell sources for use in engineered bone-ligament-bone grafts in sheep anterior cruciate ligament repair.

    PubMed

    Mahalingam, Vasudevan D; Behbahani-Nejad, Nilofar; Horine, Storm V; Olsen, Tyler J; Smietana, Michael J; Wojtys, Edward M; Wellik, Deneen M; Arruda, Ellen M; Larkin, Lisa M

    2015-03-01

    The use of autografts versus allografts for anterior cruciate ligament (ACL) reconstruction is controversial. The current popular options for ACL reconstruction are patellar tendon or hamstring autografts, yet advances in allograft technologies have made allogeneic grafts a favorable option for repair tissue. Despite this, the mismatched biomechanical properties and risk of osteoarthritis resulting from the current graft technologies have prompted the investigation of new tissue sources for ACL reconstruction. Previous work by our lab has demonstrated that tissue-engineered bone-ligament-bone (BLB) constructs generated from an allogeneic cell source develop structural and functional properties similar to those of native ACL and vascular and neural structures that exceed those of autologous patellar tendon grafts. In this study, we investigated the effectiveness of our tissue-engineered ligament constructs fabricated from autologous versus allogeneic cell sources. Our preliminary results demonstrate that 6 months postimplantation, our tissue-engineered auto- and allogeneic BLB grafts show similar histological and mechanical outcomes indicating that the autologous grafts are a viable option for ACL reconstruction. These data indicate that our tissue-engineered autologous ligament graft could be used in clinical situations where immune rejection and disease transmission may preclude allograft use.

  19. Transplantation of Tissue-Engineered Cartilage in an Animal Model (Xenograft and Autograft): Construct Validation.

    PubMed

    Nemoto, Hitoshi; Watson, Deborah; Masuda, Koichi

    2015-01-01

    Tissue engineering holds great promise for cartilage repair with minimal donor-site morbidity. The in vivo maturation of a tissue-engineered construct can be tested in the subcutaneous tissues of the same species for autografts or of immunocompromised animals for allografts or xenografts. This section describes detailed protocols for the surgical transplantation of a tissue-engineered construct into an animal model to assess construct validity.

  20. Computer-based planning of optimal donor sites for autologous osseous grafts

    NASA Astrophysics Data System (ADS)

    Krol, Zdzislaw; Chlebiej, Michal; Zerfass, Peter; Zeilhofer, Hans-Florian U.; Sader, Robert; Mikolajczak, Pawel; Keeve, Erwin

    2002-05-01

    Bone graft surgery is often necessary for reconstruction of craniofacial defects after trauma, tumor, infection or congenital malformation. In this operative technique the removed or missing bone segment is filled with a bone graft. The mainstay of the craniofacial reconstruction rests with the replacement of the defected bone by autogeneous bone grafts. To achieve sufficient incorporation of the autograft into the host bone, precise planning and simulation of the surgical intervention is required. The major problem is to determine as accurately as possible the donor site where the graft should be dissected from and to define the shape of the desired transplant. A computer-aided method for semi-automatic selection of optimal donor sites for autografts in craniofacial reconstructive surgery has been developed. The non-automatic step of graft design and constraint setting is followed by a fully automatic procedure to find the best fitting position. In extension to preceding work, a new optimization approach based on the Levenberg-Marquardt method has been implemented and embedded into our computer-based surgical planning system. This new technique enables, once the pre-processing step has been performed, selection of the optimal donor site in time less than one minute. The method has been applied during surgery planning step in more than 20 cases. The postoperative observations have shown that functional results, such as speech and chewing ability as well as restoration of bony continuity were clearly better compared to conventionally planned operations. Moreover, in most cases the duration of the surgical interventions has been distinctly reduced.

  1. The Use of Meshed Dermal Autograft in Breast Reconstruction.

    PubMed

    Zingaretti, Nicola; Guarneri, Gianni Franco; De Biasio, Fabrizio; Shoeib, Mohamed A; Parodi, Pier Camillo

    2018-02-01

    The advantages and disadvantages of acellular dermal matrix (ADM) in breast reconstruction have been well documented. ADM is commonly used in breast reconstruction, but it adds cost to the procedure and has been associated with an increased risk of seroma, flap necrosis and infectious complications. A dermal autograft may be a useful alternative to matrices, and it has a lot of advantages: more biocompatible and more likely to be retained as a free graft, low cost, well tolerated, readily available and integrated. This report discusses a new surgical technique that uses an autologous dermis, which was harvested from the controlateral breast in patients having simultaneous breast reduction/mastopexy. Before the insertion, the autologous dermal matrix was meshed at a ratio of 3:1 to increase the graft surface area, to provide additional draining and to improve the engraftment of the autologous dermal matrix. Consequently, the resulting meshed graft allows for the cover of the inferior pole of a larger breast size implant and decreases the complication rate. In our clinic, this method was used on five women; there was one limited necrosis of the mastectomy flaps. The described technique is straightforward and reliable, it adds minimally to the operative time, and it eliminates costs and covers a bigger part of the prosthesis and promises good results. No Level Assigned This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  2. Rabbit Trochlear Model of Osteochondral Allograft Transplantation

    PubMed Central

    To, Nhat; Curtiss, Shane; Neu, Corey P; Salgado, Christopher J; Jamali, Amir A

    2011-01-01

    Allografting and autografting of osteochondral tissues is a promising strategy to treat articular cartilage lesions in damaged joints. We developed a new model of fresh osteochondral allografting using the entire rabbit trochlea. The objective of the current study was to demonstrate that this model would achieve reproducible graft–host healing and maintain normal articular cartilage histologic, immunolocalization, and biochemical characteristics after transplantation under diverse storage and transplantation conditions. New Zealand white (n = 8) and Dutch belted (n = 8) rabbits underwent a 2-stage transplantation operation using osteochondral grafts that had been stored for 2 or 4 wk. Trochlear grafts harvested from the left knee were transplanted to the right knee as either autografts or allografts. Grafts were fixed with 22-gauge steel wire or 3-0 nylon suture. Rabbits were euthanized for evaluation at 1, 2, 4, 6, and 12 wk after transplantation. All grafts that remained in vivo for at least 4 wk demonstrated 100% interface healing by microCT. Trabecular bridging was present at the host–graft interface starting at 2 wk after transplantation, with no significant difference in cartilage histology between the various groups. The combined histology scores indicated minimal evidence of osteoarthritis. Immunostaining revealed that superficial zone protein was localized at the surface of all transplants. The rabbit trochlear model met our criteria for a successful model in regard to the ease of the procedure, low rate of surgical complications, relatively large articular cartilage surface area, and amount of host–graft bone interface available for analysis. PMID:22330350

  3. Comparative study of subtalar arthrodesis after calcaneal frature malunion with autologous bone graft or freeze-dried xenograft.

    PubMed

    Henning, Carlo; Poglia, Gabriel; Leie, Murilo Anderson; Galia, Carlos Roberto

    2015-12-01

    Calcaneal fracture malunion may evolve into arthrosis and severe foot deformities. The aim of this study was to identify differences in bony union following corrective subtalar arthrodesis with interposition of autologous tricortical bone graft or freeze-dried bovine xenograft. We prospectively evaluated 12 patients who underwent subtalar arthrodesis, six patients received autografts and 6 received freeze-dried bovine xenografts. After a mean followup of 58 weeks, the patients were clinical assessed using AOFAS scale and the visual analog scale (VAS) for pain and for final radiographic parameters measurement. Two blind raters evaluated the length of time required for solid union of the arthrodesis and graft integration by retrospective radiographic examination. In the autograft group, AOFAS score improved from a preoperative average of 37 to 64 points postoperatively (p = 0.02) and mean VAS score improved from 4.7 to 1.9 (p = 0.028). In the xenograft group, AOFAS score improved from 38 to 74 points (p = 0.02) and VAS from 5.5 to 2.7 (p = 0.046). Solid union was achieved in all cases in the autograft group at an average of 5.3 weeks and in five cases in the xenograft group at 8.8 weeks (p = 0.077). Graft integration occurred after an average of 10.7 weeks in the autograft group and 28.8 weeks in the xenograft group (p = 0.016). With the numbers available, no significant difference could be detected in the length of time required for solid union of subtalar arthrodesis between groups, although time to integration of freeze-dried bovine xenografts was statistically higher. Clinical and functional improvement was observed in both groups.

  4. Clinical application of a tissue-cultured skin autograft: an alternative for the treatment of non-healing or slowly healing wounds?

    PubMed

    Zöller, Nadja; Valesky, Eva; Butting, Manuel; Hofmann, Matthias; Kippenberger, Stefan; Bereiter-Hahn, Jürgen; Bernd, August; Kaufmann, Roland

    2014-01-01

    The treatment regime of non-healing or slowly healing wounds is constantly improving. One aspect is surgical defect coverage whereby mesh grafts and keratinocyte suspension are applied. Tissue-cultured skin autografts may be an alternative for the treatment of full-thickness wounds and wounds that cover large areas of the body surface. Autologous epidermal and dermal cells were isolated, expanded in vitro and seeded on collagen-elastin scaffolds. The developed autograft was immunohistochemically characterized and subsequently transplanted onto a facial chronic ulceration of a 71-year-old patient with vulnerable atrophic skin. Characterization of the skin equivalent revealed comparability to healthy human skin due to the epidermal strata, differentiation and proliferation markers. Within 138 days, the skin structure at the transplantation site closely correlated with the adjacent undisturbed skin. The present study demonstrates the comparability of the developed organotypic skin equivalent to healthy human skin and the versatility for clinical applications.

  5. Hamstring autograft versus soft-tissue allograft in anterior cruciate ligament reconstruction: a systematic review and meta-analysis of randomized controlled trials.

    PubMed

    Cvetanovich, Gregory L; Mascarenhas, Randy; Saccomanno, Maristella F; Verma, Nikhil N; Cole, Brian J; Bush-Joseph, Charles A; Bach, Bernard R

    2014-12-01

    To compare outcomes of anterior cruciate ligament (ACL) reconstruction with hamstring autograft versus soft-tissue allograft by systematic review and meta-analysis. A systematic review of randomized controlled studies comparing hamstring autograft with soft-tissue allograft in ACL reconstruction was performed. Studies were identified by strict inclusion and exclusion criteria. Descriptive statistics were reported. Where possible, the data were pooled and a meta-analysis was performed using RevMan software (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark). Dichotomous data were reported as risk ratios, whereas continuous data were reported as standardized mean differences and 95% confidence intervals. Heterogeneity was assessed by use of I(2) for each meta-analysis. Study methodologic quality was analyzed with the Modified Coleman Methodology Score and Jadad scale. Five studies with 504 combined patients (251 autograft and 253 allograft; 374 male and 130 female patients) with a mean age of 29.9 ± 2.2 years were included. The allografts used were fresh-frozen hamstring, irradiated hamstring, mixture of fresh-frozen and cryopreserved hamstring, fresh-frozen tibialis anterior, and fresh-frozen Achilles tendon grafts without bone blocks. The mean follow-up period was 47.4 ± 26.9 months, with a mean follow-up rate of 83.3% ± 8.6%. Two studies found a longer operative time with autograft than with allograft (77.1 ± 2.0 minutes v 59.9 ± 0.9 minutes, P = .008). Meta-analysis showed no statistically significant differences between autografts and allografts for any outcome measures (P > .05 for all tests). One study found significantly greater laxity for irradiated allograft than for autograft. The methodologic quality of the 5 studies was poor, with a mean Modified Coleman Methodology Score of 54.4 ± 6.9 and mean Jadad score of 1.6 ± 1.5. On the basis of this systematic review and meta-analysis of 5 randomized controlled trials, there is

  6. Is Quadriceps Tendon Autograft a Better Choice Than Hamstring Autograft for Anterior Cruciate Ligament Reconstruction? A Comparative Study With a Mean Follow-up of 3.6 Years.

    PubMed

    Cavaignac, Etienne; Coulin, Benoit; Tscholl, Philippe; Nik Mohd Fatmy, Nik; Duthon, Victoria; Menetrey, Jacques

    2017-05-01

    The quadriceps tendon (QT) autograft is known as an effective graft for anterior cruciate ligament (ACL) reconstruction and shows a similar functional outcome to the bone-patellar tendon-bone (BPTB) in randomized controlled trials, with a lesser incidence of complications. Up until now, only 2 studies have compared QT to hamstring tendon (HT) autograft. The functional outcomes of the QT technique are at least as good as those of the HT technique, with the same morbidity. Cohort study; Level of evidence, 3. Ninety-five patients underwent isolated ACL reconstruction between January 1 and December 31, 2012. Fifty underwent ACL reconstruction with the QT and 45 with the HT. The same surgical technique, fixation method, and postoperative protocol were used in both groups. The following parameters were evaluated: surgical revisions, functional outcome (Lysholm, Knee injury and Osteoarthritis Outcome Score [KOOS], Tegner, subjective International Knee Documentation Committee), joint stability (KT-1000, Lachman, pivot shift), anterior knee pain (Shelbourne-Trumper score), and isokinetic strength. Descriptive statistics are presented for these variables using the Student t test. Eighty-six patients (45 QT, 41 HT) were reviewed with a mean follow-up of 3.6 ± 0.4 years; minimum follow-up was 3 years. There were 4 reoperations in the QT group (including 1 ACL revision) and 3 in the HT group (including 2 ACL revisions) ( P > .05). The Lysholm (89 ± 6.9 vs 83.1 ± 5.3), KOOS Symptoms (90 ± 11.2 vs 81 ± 10.3), and KOOS Sport (82 ± 11.3 vs 67 ± 12.4) scores were significantly better in the QT group than in the HT group. In terms of stability, the mean side-to-side difference was 1.1 ± 0.9 mm for the QT group and 3.1 ± 1.3 mm for the HT group based on KT-1000 measurements ( P < .005). The negative Lachman component was higher in the QT group than in the HT group (90% vs 46%, P < .005). There was a trend for the negative pivot-shift component to be higher in the QT group

  7. Can Grafts Provide Superior Tendon Healing and Clinical Outcomes After Rotator Cuff Repairs?

    PubMed Central

    Ono, Yohei; Dávalos Herrera, Diego Alejandro; Woodmass, Jarret M.; Boorman, Richard S.; Thornton, Gail M.; Lo, Ian K. Y.

    2016-01-01

    Background: Arthroscopic repair of large to massive rotator cuff tears commonly retear. To improve healing rates, a number of different approaches have been utilized, including the use of grafts, which may enhance the biomechanical and biologic aspects of the repair construct. However, the outcomes after the use of grafts are diverse. Purpose: To systematically review the literature for large to massive rotator cuff tears to determine whether the use of grafts generally provides superior tendon healing and clinical outcomes to the repairs without grafts. Study Design: Systematic review; Level of evidence, 3. Methods: A systematic review of the literature was performed. Clinical studies comparing the repairs with (graft group) and without grafts (control group) were included and analyzed. The primary outcome was tendon healing on either magnetic resonance imaging or ultrasound. The secondary outcome measures included visual analog scale for pain, University of California at Los Angles (UCLA) score, and forward elevation range. Differences between groups in all outcome measures were statistically analyzed. Results: Six comparative studies (level of evidence 2 or 3) with 13 study groups were included. A total of 242 repairs in the graft group (mean age, 62.5 ± 4.6 years) and 185 repairs in the control group (mean age, 62.5 ± 5.0 years) were analyzed. The graft types utilized included autograft (fascia lata) in 1 study, allograft (human dermis) in 2 studies, xenograft (bovine pericardium, porcine small intestine submucosa) in 2 studies, synthetic graft (polypropylene) in 1 study, and a combination of autograft (the long head of biceps) and synthetic graft (polypropylene) in 1 study. The overall mean follow-up time was 28.4 ± 9.0 months. When 1 or 2 studies/study groups were excluded due to practical or statistical reasons, the graft group demonstrated significantly improved healing (odds ratio, 2.48; 95% CI, 1.58-3.90; P < .0001) and all clinical outcome measures at

  8. Evaluation of synthetic vascular grafts in a mouse carotid grafting model.

    PubMed

    Chan, Alex H P; Tan, Richard P; Michael, Praveesuda L; Lee, Bob S L; Vanags, Laura Z; Ng, Martin K C; Bursill, Christina A; Wise, Steven G

    2017-01-01

    Current animal models for the evaluation of synthetic grafts are lacking many of the molecular tools and transgenic studies available to other branches of biology. A mouse model of vascular grafting would allow for the study of molecular mechanisms of graft failure, including in the context of clinically relevant disease states. In this study, we comprehensively characterise a sutureless grafting model which facilitates the evaluation of synthetic grafts in the mouse carotid artery. Using conduits electrospun from polycaprolactone (PCL) we show the gradual development of a significant neointima within 28 days, found to be greatest at the anastomoses. Histological analysis showed temporal increases in smooth muscle cell and collagen content within the neointima, demonstrating its maturation. Endothelialisation of the PCL grafts, assessed by scanning electron microscopy (SEM) analysis and CD31 staining, was near complete within 28 days, together replicating two critical aspects of graft performance. To further demonstrate the potential of this mouse model, we used longitudinal non-invasive tracking of bone-marrow mononuclear cells from a transgenic mouse strain with a dual reporter construct encoding both luciferase and green fluorescent protein (GFP). This enabled characterisation of mononuclear cell homing and engraftment to PCL using bioluminescence imaging and histological staining over time (7, 14 and 28 days). We observed peak luminescence at 7 days post-graft implantation that persisted until sacrifice at 28 days. Collectively, we have established and characterised a high-throughput model of grafting that allows for the evaluation of key clinical drivers of graft performance.

  9. Comparative morphometric analysis of 5 interpositional arterial autograft options for adult living donor liver transplantation.

    PubMed

    Imakuma, E S; Bordini, A L; Millan, L S; Massarollo, P C B; Caldini, E T E G

    2014-01-01

    In living donor liver transplantation, the right-sided graft presents thin and short vessels, bringing forward a more difficult anastomosis. In these cases, an interpositional arterial autograft can be used to favor the performance of the arterial anastomosis, making the procedure easier and avoiding surgical complications. We compared the inferior mesenteric artery (IMA), the splenic artery (SA), the inferior epigastric artery (IEA), the descending branch of the lateral circumflex femoral artery (LCFA), and the proper hepatic artery (PHA) as options for interpositional autograft in living donor liver transplantation. Segments of at least 3 cm of all 5 arteries were harvested from 16 fresh adult cadavers from both genders through standardized dissection. The analyzed measures were proximal and distal diameter and length. The proximal diameter of the RHA and the distal diameter of the SA, IMA, IEA and the LCFA were compared to the distal diameter of the RHA. The proximal and distal diameters of the SA, IEA and LCFA were compared to study caliber gain of each artery. All arteries except the IMA showed statistical significant difference in relation to the RHA in terms of diameter. Regarding caliber gain, the arteries demonstrated statistical significant difference. All the harvested arteries except PHA were 3 cm in length. The IMA demonstrated the best compatibility with the RHA in terms of diameter and showed sufficient length to be employed as interpositional graft. The PHA, the SA, the IEA and the LCFA presented statistically significant different diameters when compared to the RHA. Among these vessels, only the PHA did not show sufficient mean length. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Decreased serum estrogen improves fat graft retention by enhancing early macrophage infiltration and inducing adipocyte hypertrophy.

    PubMed

    Mok, Hsiaopei; Feng, Jingwei; Hu, Wansheng; Wang, Jing; Cai, Junrong; Lu, Feng

    2018-06-18

    Fat grafting is a commonly used procedure; however, the mechanisms that regulate graft outcomes are not clear. Estrogen has been associated with vascularization, inflammation and fat metabolism, yet its role in fat grafting is unclear. Mice were implanted with 17β-estradiol pellets (high estrogen, HE), underwent ovariectomy (low estrogen level, OVX) or sham surgery (normal estrogen level, CON). 45 days later, inguinal fat of mice was autografted subcutaneously. At 1, 2, 4, and 12 weeks post-transplantation, grafts were dissected, weighed, and assessed for histology, angiogenesis and inflammation level. Serum estrogen level correlated to estrogen manipulation. 12 weeks after autografting, the retention rate was significantly higher in the OVX (79% ± 30%) than in the HE (16% ± 8%) and CON (35% ± 13%) groups. OVX-grafts had the least necrosis and most hypertrophic fat. OVX recruited the most pro-inflammatory macrophages and demonstrated a faster dead tissue removal process, however a higher fibrogenic tendency was found in this group. HE grafts had the most Sca1+ local stem cells and CD31  +  capillary content; however, with a low level of acute inflammation and insufficient adipokine PPAR-γ expression, their retention rate was impaired. Elevated serum estrogen increased stem cell density and early vascularization; however, by inhibiting the early inflammation, it resulted in delayed necrotic tissue removal and finally led to impaired adipose restoration. A low estrogen level induced favorable inflammation status and adipocyte hypertrophy to improve fat graft retention, but a continuing decreased estrogen level led to fat graft fibrosis. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Successful fifth metatarsal bulk autograft reconstruction of thermal necrosis post intramedullary fixation.

    PubMed

    Veljkovic, Andrea; Le, Vu; Escudero, Mario; Salat, Peter; Wing, Kevin; Penner, Murray; Younger, Alastair

    2018-03-21

    Reamed intramedullary (IM) screw fixation for proximal fifth metatarsal fractures is technically challenging with potentially devastating complications if basic principles are not followed. A case of an iatrogenic fourth-degree burn after elective reamed IM screw fixation of a proximal fifth metatarsal fracture in a high-level athlete is reported. The case was complicated by postoperative osteomyelitis with third-degree soft-tissue defect. This was successfully treated with staged autologous bone graft reconstruction, tendon reconstruction, and local bi-pedicle flap coverage. The patient returned to competitive-level sports, avoiding the need for fifth ray amputation. Critical points of the IM screw technique and definitive reconstruction are discussed. Bulk autograft reconstruction is a safe and effective alternative to ray amputation in segmental defects of the fifth metatarsal.Level of evidence V.

  12. Clinical results of primary malignant musculoskeletal tumor treated by wide resection and recycling autograft reconstruction using liquid nitrogen.

    PubMed

    Paholpak, Permsak; Sirichativapee, Winai; Wisanuyotin, Taweechok; Kosuwon, Weerachai; Jeeravipoolvarn, Polasak

    2015-06-01

    To evaluate the clinical results of primary malignant musculoskeletal tumors treated with wide resection and recycling autograft reconstruction using liquid nitrogen. We reviewed 12 patients who had a primary malignant bone and soft tissue tumor treated by wide resection and recycling autograft reconstruction using liquid nitrogen between March 2006 and March 2013. The results were judged by recurrence, functional status and complications. Functional status was assessed according to the Musculoskeletal Tumor Society Score (MSTSS). Clinical failure was defined as need for reoperation in order to change the type of reconstruction or to amputate, and the presence of local recurrence. The most common tumor was osteosarcoma (eight cases) followed by Ewing's sarcoma (two cases). The tibia was the most frequently involved skeletal site (six cases) followed by the femur (three cases). The median follow-up period was 32 months. In 12 patients, 7 were still alive without recurrence. There were 3 clinical failures: 1 local recurrence and 2 graft complications at 28, 51 and 20 months after reconstruction, respectively. The main complication was infection (three cases). All osteotomy sites were radiographic unions, and the union time was 8.2 ± 2.7 months. The mean ± SD MSTSS score was 79% ± 11%; excellent functional results were achieved in seven patients. Recycling autograft reconstruction using liquid nitrogen had favorable clinical outcomes in terms of functional status and local recurrence. This reconstruction method, therefore, represents a reasonable alternative for limb salvage surgery. © 2014 Wiley Publishing Asia Pty Ltd.

  13. Which is the best method of sterilization for recycled bone autograft in limb salvage surgery: a radiological, biomechanical and histopathological study in rabbit.

    PubMed

    Yasin, Nor Faissal; Ajit Singh, Vivek; Saad, Marniza; Omar, Effat

    2015-04-15

    Limb salvage surgery is a treatment of choice for sarcomas of the extremities. One of the options in skeletal reconstruction after tumour resection is by using a recycled bone autograft. The present accepted methods of recycling bone autografts include autoclaving, pasteurization and irradiation. At the moment there is lack of studies that compare the effectiveness of various sterilization methods used for recycling bone autografts and their effects in terms of bone incorporation. This study was performed to determine the effects of different methods of sterilization on bone autografts in rabbit by radiological, biomechanical and histopathological evaluations. Fresh rabbit cortical bone is harvested from the tibial diaphysis and sterilized extracorporeally by pasteurization (n = 6), autoclaving (n = 6), irradiation (n = 6) and normal saline as control group (n = 6). The cortical bones were immediately reimplanted after the sterilization process. The subsequent process of graft incorporation was examined over a period of 12 weeks by serial radiographs, biomechanical and histopathological evaluations. Statistical analysis (ANOVA) was performed on these results. Significance level (α) and power (β) were set to 0.05 and 0.90, respectively. Radiographic analysis showed that irradiation group has higher score in bony union compared to other sterilization groups (p = 0.041). ANOVA analysis of 'failure stress', 'modulus' and 'strain to failure' demonstrated no significant differences (p = 0.389) between treated and untreated specimens under mechanical loading. In macroscopic histopathological analysis, the irradiated group has the highest percentage of bony union (91.7 percent). However in microscopic analysis of union, the pasteurization group has significantly higher score (p = 0.041) in callus formation, osteocytes percentage and bone marrow cellularity at the end of the study indicating good union potential. This experimental study shown that both irradiation and

  14. Analysis of factors predicting speed of hematologic recovery after transplantation with 4-hydroperoxycyclophosphamide-purged autologous bone marrow grafts.

    PubMed

    Rowley, S D; Piantadosi, S; Marcellus, D C; Jones, R J; Davidson, N E; Davis, J M; Kennedy, J; Wiley, J M; Wingard, J R; Yeager, A M

    1991-03-01

    We previously described the predictive value of graft colony-forming units granulocyte macrophage (CFU-GM) content after 4-hydroperoxycyclophosphamide (4-HC) purging for the duration of aplasia after autologous bone marrow transplantation. Despite the uniform 4-HC concentration, we observed heterogeneity in CFU-GM survival and the kinetics of engraftment. We have now analysed patient and graft characteristics for 154 patients undergoing autologous transplantation with 4-HC purged grafts to further define this heterogeneity. Patients transplanted for the treatment of malignant lymphoma reached a peripheral blood granulocyte count of greater than 0.5 x 10(9)/l (median, 20 versus 40 days; p less than 0.001) and platelet transfusion independence (median, 30 versus 70 days; p less than 0.001) significantly faster than patients transplanted for acute non-lymphoblastic leukemia. Other diagnostic groups were intermediate. These differences were independent of graft CFU-GM content. Multiple other patient and graft factors including patient age, peripheral blood counts on day of harvest, and amounts of other hematopoietic progenitors also predicted the kinetics of engraftment in univariate and multivariate analysis. Cytomegalovirus infection during the aplastic period predicted a delay in granulocyte (p = 0.024) but not platelet recovery (p = 0.174). This analysis demonstrates that multiple patient, graft, and post-transplant factors predict the engraftment capacity of autografts, and the kinetics of engraftment with 4-HC purged grafts. The multiple predictive factors explain a significant portion of the variability in engraftment kinetics observed after transplantation with 4-HC purged autografts.

  15. The evaluation of muscle recovery after anatomical single-bundle ACL reconstruction using a quadriceps autograft.

    PubMed

    Iriuchishima, Takanori; Ryu, Keinosuke; Okano, Tatsumasa; Suruga, Makoto; Aizawa, Shin; Fu, Freddie H

    2017-05-01

    The purpose of this study was to reveal the degree of muscle recovery and report the clinical results of anatomical single-bundle ACL reconstruction using a quadriceps autograft. Twenty subjects undergoing anatomical single-bundle ACL reconstruction using a quadriceps autograft were included in this study. A 5-mm-wide, 8-cm-long graft, involving the entire layer of the quadriceps tendon, was harvested without bone block. The average graft diameter was 8.1 ± 1.4 mm. An initial tension of 30 N was applied. The femoral tunnel was created from the far-medial portal. Each femoral and tibial tunnel was created close to the antero-medial bundle insertion site. For the evaluation of muscle recovery (quadriceps and hamstring), a handheld dynamometer was used. The evaluation of muscle recovery was performed pre-operatively, and at 3, 6, 9, and 12 months after surgery. Muscle recovery data were calculated as a percentage of leg strength in the non-operated leg. Anterior tibial translation (ATT), pivot shift test, and IKDC score were evaluated. The average quadriceps strength pre-operatively, and at 3, 6, 9, and 12 months after ACL reconstruction was 90.5 ± 19, 67.8 ± 21.4, 84 ± 17.5, and 85.1 ± 12.6 %, respectively. The average hamstring strength pre-operatively, and at 3, 6, 9, and 12 months after ACL reconstruction was 99.5 ± 13.7, 78.7 ± 11.4, 90.5 ± 19, and 96.7 ± 13.8 %, respectively. ATT pre-operatively and at 12 months after surgery was 5.4 ± 1.3 and 1.0 ± 0.8 mm, respectively. No subjects exhibited positive pivot shift after surgery. Within 6 months following surgery, quadriceps hypotrophy was observed in all subjects. However, the hypotrophy had recovered at 12 months following surgery. No subjects complained of donor site pain after surgery. Anatomical single-bundle ACL reconstruction using a quadriceps autograft resulted in equivalent level of muscle recovery and knee stability when compared with previously reported ACL

  16. Anterior Cruciate Ligament-Derived Stem Cells Transduced With BMP2 Accelerate Graft-Bone Integration After ACL Reconstruction.

    PubMed

    Kawakami, Yohei; Takayama, Koji; Matsumoto, Tomoyuki; Tang, Ying; Wang, Bing; Mifune, Yutaka; Cummins, James H; Warth, Ryan J; Kuroda, Ryosuke; Kurosaka, Masahiro; Fu, Freddie H; Huard, Johnny

    2017-03-01

    Strong graft-bone integration is a prerequisite for successful graft remodeling after reconstruction of the anterior cruciate ligament (ACL) using soft tissue grafts. Novel strategies to accelerate soft tissue graft-bone integration are needed to reduce the need for bone-tendon-bone graft harvest, reduce patient convalescence, facilitate rehabilitation, and reduce total recovery time after ACL reconstruction. The application of ACL-derived stem cells with enhanced expression of bone morphogenetic protein 2 (BMP2) onto soft tissue grafts in the form of cell sheets will both accelerate and improve the quality of graft-bone integration after ACL reconstruction in a rat model. Controlled laboratory study. ACL-derived CD34+ cells were isolated from remnant human ACL tissues, virally transduced to express BMP2, and embedded within cell sheets. In a rat model of ACL injury, bilateral single-bundle ACL reconstructions were performed, in which cell sheets were wrapped around tendon autografts before reconstruction. Four groups containing a total of 48 rats (96 knees) were established (n = 12 rats; 24 knees per group): CD34+BMP2 (100%), CD34+BMP2 (25%), CD34+ (untransduced), and a control group containing no cells. Six rats from each group were euthanized 2 and 4 weeks after surgery, and each graft was harvested for immunohistochemical and histological analyses. The remaining 6 rats in each group were euthanized at 4 and 8 weeks to evaluate in situ tensile load to failure in each femur-graft-tibia complex. In vitro, BMP2 transduction promoted the osteogenic differentiation of ACL-derived CD34+ cells while retaining their intrinsic multipotent capabilities. Osteoblast densities were greatest in the BMP2 (100%) and BMP2 (25%) groups. Bone tunnels in the CD34+BMP2 (100%) and CD34+BMP2 (25%) groups had the smallest cross-sectional areas according to micro-computed tomography analyses. Graft-bone integration occurred most rapidly in the CD34+BMP2 (25%) group. Tensile load to

  17. Ipsilateral femoral autograft reconstruction after resection of a pelvic tumor.

    PubMed

    Biau, David J; Thévenin, Fabrice; Dumaine, Valérie; Babinet, Antoine; Tomeno, Bernard; Anract, Philippe

    2009-01-01

    Reconstruction of bone after the resection of a pelvic tumor is challenging. The purpose of the present study was to evaluate the use of the ipsilateral femur as the graft material for reconstruction. We performed a retrospective review of thirteen patients with a malignant pelvic lesion who underwent resection followed by reconstruction with an ipsilateral femoral autograft and insertion of a total hip replacement. The study group included nine men and four women with a median age of fifty-one years at the time of the reconstruction. The diagnosis was chondrosarcoma in eight patients, metastasis in three, and myeloma and radiation-induced malignant disease in one each. The surviving patients were assessed functionally and radiographically; the cumulative probability of revision was estimated while taking into account competing risks. The median duration of follow-up was forty-nine months. At the time of the latest follow-up, seven patients were alive and disease-free and six had died from metastatic disease. Four patients had had revision of the reconstruction, two for the treatment of mechanical complications and two for the treatment of infection. Three other patients had mechanical complications but had not had a revision. The cumulative probability of revision of the reconstruction for mechanical failure was 8% (95% confidence interval, 0% to 23%), 8% (95% confidence interval, 0% to 23%), and 16% (95% confidence interval, 0% to 39%) at one, two, and four years, respectively. Although it has attendant complications consistent with pelvic tumor surgery, an ipsilateral femoral autograft reconstruction may be an option for reconstruction of pelvic discontinuity in a subgroup of patients following tumor resection. This innovative procedure requires longer-term follow-up studies.

  18. The indications and donor-site morbidity of tibial cortical strut autografts in the management of defects in long bones.

    PubMed

    Lauthe, O; Soubeyrand, M; Babinet, A; Dumaine, V; Anract, P; Biau, D J

    2018-05-01

    Aims The primary aim of this study was to determine the morbidity of a tibial strut autograft and characterize the rate of bony union following its use. Patients and Methods We retrospectively assessed a series of 104 patients from a single centre who were treated with a tibial strut autograft of > 5 cm in length. A total of 30 had a segmental reconstruction with continuity of bone, 27 had a segmental reconstruction without continuity of bone, 29 had an arthrodesis and 18 had a nonunion. Donor-site morbidity was defined as any event that required a modification of the postoperative management. Union was assessed clinically and radiologically at a median of 36 months (IQR, 14 to 74). Results Donor-site morbidity occurred in four patients (4%; 95% confidence interval (CI) 1 to 10). One patient had a stress fracture of the tibia, which healed with a varus deformity, requiring an osteotomy. Two patients required evacuation of a haematoma and one developed anterior compartment syndrome which required fasciotomies. The cumulative probability of union was 90% (95% CI 80 to 96) at five years. The type of reconstruction (p = 0.018), continuity of bone (p = 0.006) and length of tibial graft (p = 0.037) were associated with the time to union. Conclusion The tibial strut autograft has a low risk of morbidity and provides adequate bone stock for treating various defects of long bones. Cite this article: Bone Joint J 2018;100-B:667-74.

  19. Design and optimization of a tissue-engineered bone graft substitute

    NASA Astrophysics Data System (ADS)

    Shimko, Daniel Andrew

    2004-12-01

    In 2000, 3.1 million surgical procedures on the musculoskeletal system were reported in the United States. For many of these cases, bone grafting was essential for successful fracture stabilization. Current techniques use intact bone obtained either from the patient (autograft) or a cadaver (allograft) to repair large defects, however, neither source is optimal. Allografts suffer integration problems, and for autografts, the tissue supply is limited. Because of these shortcomings, and the high demand for graft tissues, alternatives are being explored. To successfully engineer a bone graft replacement, one must employ a three pronged research approach, addressing (1) the cells that will inhabit the new tissue, (2) the culture environment that these cells will be exposed to, and (3) the scaffold in which these cells will reside. The work herein examines each of these three aspects in great detail. Both adult and embryonic stem cells (ESCs) were considered for the tissue-engineered bone graft. Both exhibited desirable qualities, however, neither were optimal in all categories examined. In the end, the possibility of teratoma formation and ethical issues surrounding ESCs, made the use of adult marrow-derived stem cells in the remaining experiments obligatory. In subsequent experiments, the adult stem cells' ability to form bone was optimized. Basic fibroblast growth factor, fetal bovine serum, and extracellular calcium supplementation studies were all performed. Ultimately, adult stem cells cultured in alpha-MEM supplemented with 10% fetal bovine serum, 10mM beta-glycerophosphate, 10nM dexamethasone, 50mug/ml ascorbic acid, 1%(v/v) antibiotic/antimycotic, and 10.4mM CaCl2 performed the best, producing nearly four times more mineral than any other medium formulation. Several scaffolds were then investigated including those fabricated from poly(alpha-hydroxy esters), tantalum, and poly-methylmethacrylate. In the final study, the most appealing cell type, medium

  20. Development and validation of technique for in-vivo 3D analysis of cranial bone graft survival

    NASA Astrophysics Data System (ADS)

    Bernstein, Mark P.; Caldwell, Curtis B.; Antonyshyn, Oleh M.; Ma, Karen; Cooper, Perry W.; Ehrlich, Lisa E.

    1997-05-01

    Bone autografts are routinely employed in the reconstruction of facial deformities resulting from trauma, tumor ablation or congenital malformations. The combined use of post- operative 3D CT and SPECT imaging provides a means for quantitative in vivo evaluation of bone graft volume and osteoblastic activity. The specific objectives of this study were: (1) Determine the reliability and accuracy of interactive computer-assisted analysis of bone graft volumes based on 3D CT scans; (2) Determine the error in CT/SPECT multimodality image registration; (3) Determine the error in SPECT/SPECT image registration; and (4) Determine the reliability and accuracy of CT-guided SPECT uptake measurements in cranial bone grafts. Five human cadaver heads served as anthropomorphic models for all experiments. Four cranial defects were created in each specimen with inlay and onlay split skull bone grafts and reconstructed to skull and malar recipient sites. To acquire all images, each specimen was CT scanned and coated with Technetium doped paint. For purposes of validation, skulls were landmarked with 1/16-inch ball-bearings and Indium. This study provides a new technique relating anatomy and physiology for the analysis of cranial bone graft survival.

  1. Irradiated Hamstring Tendon Allograft Versus Autograft for Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction: Midterm Clinical Outcomes.

    PubMed

    Tian, Shaoqi; Wang, Bin; Liu, Lun; Wang, Yuanhe; Ha, Chengzhi; Li, Qicai; Yang, Xu; Sun, Kang

    2016-10-01

    Most studies on grafts for anterior cruciate ligament (ACL) reconstruction (ACLR) have been of autografts or nonirradiated allografts with a single-bundle (SB) technique. Outcome reports evaluating anatomic double-bundle (DB) ACLR with a hamstring tendon autograft versus irradiated allograft are rare. To compare the clinical outcomes of arthroscopic anatomic DB ACLR with a hamstring tendon autograft versus irradiated allograft. Randomized controlled trial; Level of evidence, 2. Between 2008 and 2009, a total of 107 patients undergoing arthroscopic DB ACLR were prospectively randomized consecutively into 1 of 2 groups (autograft [Auto] group and irradiated allograft [Ir-Allo] group). All the surgical procedures were performed by the same senior surgeon using the DB reconstruction technique. All irradiated hamstring tendon allografts were sterilized with 2.5 Mrad of irradiation before distribution and were obtained from a single certified tissue bank. Graft fixation on the femoral side was by an Endobutton, and on the tibial side by a bioabsorbable interference screw augmented with a staple. The same rehabilitation protocol was applied to all patients. Before surgery and at a mean of 6.9 years of follow-up, patients were evaluated by the same observer according to objective and subjective clinical evaluations including detailed history, physical examination, radiography, functional knee ligament testing, KT-2000 arthrometer testing, Harner vertical jump and Daniel 1-legged hop tests, Lysholm score, Tegner score, International Knee Documentation Committee (IKDC) standard evaluation form, and Cincinnati knee score. A total of 83 patients (Auto: n = 40 [mean age, 29.2 ± 6.9 years]; Ir-Allo: n = 43 [mean age, 28.6 ± 7.2 years]) fulfilled follow-up and clinical evaluations. No significant differences were found between the 2 groups according to the overall IKDC functional and subjective evaluations as well as testing of activity levels. Significant between

  2. Successful vitrification and autografting of baboon (Papio anubis) ovarian tissue.

    PubMed

    Amorim, Christiani A; Jacobs, Sophie; Devireddy, Ram V; Van Langendonckt, Anne; Vanacker, Julie; Jaeger, Jonathan; Luyckx, Valérie; Donnez, Jacques; Dolmans, Marie-Madeleine

    2013-08-01

    Can a vitrification protocol using an ethylene glycol/dimethyl sulphoxide-based solution and a cryopin successfully cryopreserve baboon ovarian tissue? Our results show that baboon ovarian tissue can be successfully cryopreserved with our vitrification protocol. Non-human primates have already been used as an animal model to test vitrification protocols for human ovarian tissue cryopreservation. Ovarian biopsies from five adult baboons were vitrified, warmed and autografted for 5 months. After grafting, follicle survival, growth and function and also the quality of stromal tissue were assessed histologically and by immunohistochemistry. The influence of the vitrification procedure on the cooling rate was evaluated by a computer model. After vitrification, warming and long-term grafting, follicles were able to grow and maintain their function, as illustrated by Ki67, anti-Müllerian hormone (AMH) and growth differentiation factor-9 (GDF-9) immunostaining. Corpora lutea were also observed, evidencing successful ovulation in all the animals. Stromal tissue quality did not appear to be negatively affected by our cryopreservation procedure, as demonstrated by vascularization and proportions of fibrotic areas, which were similar to those found in fresh ungrafted ovarian tissue. Despite our promising findings, before applying this technique in a clinical setting, we need to validate it by achieving pregnancies. In addition to encouraging results obtained with our vitrification procedure for non-human ovarian tissue, this study also showed, for the first time, expression of AMH and GDF-9 in ovarian follicles. This study was supported by grants from the Fonds National de la Recherche Scientifique de Belgique (grant Télévie No. 7.4507.10, grant 3.4.590.08 awarded to Marie-Madeleine Dolmans), Fonds Spéciaux de Recherche, Fondation St Luc, Foundation Against Cancer, and Department of Mechanical Engineering at Louisiana State University (support to Ram Devireddy), and

  3. The Composite of Bone Marrow Concentrate and PRP as an Alternative to Autologous Bone Grafting

    PubMed Central

    Hakimi, Mohssen; Grassmann, Jan-Peter; Betsch, Marcel; Schneppendahl, Johannes; Gehrmann, Sebastian; Hakimi, Ahmad-Reza; Kröpil, Patric; Sager, Martin; Herten, Monika; Wild, Michael; Windolf, Joachim; Jungbluth, Pascal

    2014-01-01

    One possible alternative to the application of autologous bone grafts represents the use of autologous bone marrow concentrate (BMC). The purpose of our study was to evaluate the potency of autologous platelet-rich plasma (PRP) in combination with BMC. In 32 mini-pigs a metaphyseal critical-size defect was surgically created at the proximal tibia. The animals were allocated to four treatment groups of eight animals each (1. BMC+CPG group, 2. BMC+CPG+PRP group, 3. autograft group, 4. CPG group). In the BMC+CPG group the defect was filled with autologous BMC in combination with calcium phosphate granules (CPG), whereas in the BMC+CPG+PRP group the defect was filled with the composite of autologous BMC, CPG and autologous PRP. In the autograft group the defect was filled with autologous cancellous graft, whereas in the CPG group the defect was filled with CPG solely. After 6 weeks radiological and histomorphometrical analysis showed significantly more new bone formation in the BMC+CPG+PRP group compared to the BMC+CPG group and the CPG group. There were no significant differences between the BMC+CPG+PRP group and the autograft group. In the PRP platelets were enriched significantly about 4.7-fold compared to native blood. In BMC the count of mononuclear cells increased significantly (3.5-fold) compared to the bone marrow aspirate. This study demonstrates that the composite of BMC+CPG+PRP leads to a significantly higher bone regeneration of critical-size defects at the proximal tibia in mini-pigs than the use of BMC+CPG without PRP. Furthermore, within the limits of the present study the composite BMC+CPG+PRP represents a comparable alternative to autologous bone grafting. PMID:24950251

  4. Stress fracture as a complication of autogenous bone graft harvest from the distal tibia.

    PubMed

    Chou, Loretta B; Mann, Roger A; Coughlin, Michael J; McPeake, William T; Mizel, Mark S

    2007-02-01

    Autogenous bone graft from the distal tibia provides cancellous bone graft for foot and ankle operations, and it has osteogenic and osteoconductive properties. The site is in close proximity to the foot and ankle, and published retrospective studies show low morbidity from the procedure. One-hundred autografts were obtained from the distal tibia between 2000 and 2003. In four cases the distal tibial bone graft harvest resulted in a stress fracture. There were three women and one man. The average time of diagnosis of the stress fracture from the operation was 1.8 months. All stress fractures healed with a short course (average 2.4 months) of cast immobilization. This study demonstrated that a stress fracture from the donor site of autogenous bone graft of the distal tibia occurs and can be successfully treated nonoperatively.

  5. Large pterygium surgery: When coverage of the scleral bed justifies graft rotation.

    PubMed

    Gargallo-Benedicto, A; Hernández Pérez, D; Olate-Pérez, Á; Betancur-Delgado, E; Cerdà-Ibáñez, M; Duch-Samper, A

    2016-10-01

    To perform a 12 month follow-up study to assess the safety and effectiveness of resection and conjunctival autograft fixed with Tissucol® in selected cases of large pterygium. The orientation of the graft was adapted to the morphology of the scleral bed for a better coverage free of traction, with limbal position being lost. A prospective, non-comparative study of 10 cases of grade II or superior pterygium (7 primary, 3 recurrent) with at least 8mm of limbal extension. A wide scleral bed was obtained after pterygium and Tenon resection, with larger grafts being required to cover the defects. A superior conjunctival autograft was harvested and fixed to bare sclera using Tissucol. The orientation was adapted to the morphology of the scleral bed and limbal position was lost. Patients were periodically assessed for recurrence and complications for a period of 12 months. Minor complications occurred in 4 eyes. In one case a buttonhole was formed during dissection of the graft. Two presented with small limbal dehiscence, but epithelialisation was completed in the first week. In a third case, it was necessary to increase topical corticosteroids for pyogenic granuloma on the donor site, with secondary increased intraocular pressure (IOP). There were no recurrences after 12 months follow-up. A conjunctival graft of appropriate size adapted to the morphology of the scleral bed to ensure good coverage free of tension, provides good surgical results in selected cases of pterygium, regardless of the conservation the limbal orientation, with no recurrences after one year follow-up. Copyright © 2016 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  6. Effects of early combinatorial treatment of autologous split-thickness skin grafts in red duroc pig model using pulsed dye laser and fractional CO2 laser.

    PubMed

    Bailey, J Kevin; Blackstone, Britani N; DeBruler, Danielle M; Kim, Jayne Y; Baumann, Molly E; McFarland, Kevin L; Imeokparia, Folasade O; Supp, Dorothy M; Powell, Heather M

    2018-01-01

    The use of pulsed dye laser (PDL) and fractional CO 2 (FX CO 2 ) laser therapy to treat and/or prevent scarring following burn injury is becoming more widespread with a number of studies reporting reduction in scar erythema and pruritus following treatment with lasers. While the majority of studies report positive outcomes following PDL or FX CO 2 therapy, a number of studies have reported no benefit or worsening of the scar following treatment. The objective of this study was to directly compare the efficacy of PDL, FX CO 2 , and PDL + FX CO 2 laser therapy in reducing scarring post burn injury and autografting in a standardized animal model. Eight female red Duroc pigs (FRDP) received 4 standardized, 1 in. x 1 in. third degree burns that were excised and autografted. Wound sites were treated with PDL, FX CO 2 , or both at 4, 8, and 12 weeks post grafting. Grafts receiving no laser therapy served as controls. Scar appearance, morphology, size, and erythema were assessed and punch biopsies collected at weeks 4, 8, 12, and 16. At week 16, additional tissue was collected for biomechanical analyses and markers for inflammatory cytokines, extracellular matrix (ECM) proteins, re-epithelialization, pigmentation, and angiogenesis were quantified at all time points using qRT-PCR. Treatment with PDL, FX CO 2 , or PDL + FX CO 2 resulted in significantly less contraction versus skin graft only controls with no statistically significant difference among laser therapy groups. Scars treated with both PDL and FX CO 2 were visually more erythematous than other groups with a significant increase in redness between two and three standard deviations above normal skin redness. Scars treated with FX CO 2 were visually smoother and contained significantly fewer wrinkles. In addition, hyperpigmentation was significantly reduced in scars treated with FX CO 2 . The use of fractional carbon dioxide or pulsed dye laser therapy within 1 month of autografting significantly reduced scar

  7. Osteointegration of soft tissue grafts within the bone tunnels in anterior cruciate ligament reconstruction can be enhanced.

    PubMed

    Kuang, Guan-Ming; Yau, W P; Lu, William W; Chiu, K Y

    2010-08-01

    Anterior cruciate ligament reconstruction with a soft tissue autograft (hamstring autograft) has grown in popularity in the last 10 years. However, the issues of a relatively long healing time and an inferior histological healing result in terms of Sharpey-like fibers connection in soft tissue grafts are still unsolved. To obtain a promising outcome in the long run, prompt osteointegration of the tendon graft within the bone tunnel is essential. In recent decades, numerous methods have been reported to enhance osteointegration of soft tissue graft in the bone tunnel. In this article, we review the current literature in this research area, mainly focusing on strategies applied to the local bone tunnel environment. Biological strategies such as stem cell and gene transfer technology, as well as the local application of specific growth factors have been reported to yield exciting results. The use of biological bone substitute and physical stimulation also obtained promising results. Artificially engineered tissue has promise as a solution to the problem of donor site morbidity. Despite these encouraging results, the current available evidence is still experimental. Further clinical studies in terms of randomized control trial in the future should be conducted to extrapolate these basic science study findings into clinical practice.

  8. [Ursolic acid inhibits corneal graft rejection following orthotopic allograft transplantation in rats].

    PubMed

    Wang, Bo; Wu, Jing; Ma, Ming; Li, Ping-Ping; Yu, Jian

    2015-04-01

    To investigate the effects of ursolic acid on corneal graft rejection in a rat model of othotopic corneal allograft transplantation. Forty-eight recipient Wistar rats were divided into normal control group with saline treatment (group A), autograft group with saline treatment (group B), SD rat allograft group with saline treatment (group C), and SD rat allograft group with intraperitoneal ursolic acid (UA) treatment group (group D). The rats received saline or UC (20 mg·kg(-1)·d(-1)) treatment for 12 days following othotopic graft transplantation. The grafts were evaluated using the Larkin corneal rejection rating system, and the graft survival was assessed with Kaplan-Meier analysis. On day 14, the grafts were harvested for histological examination, Western blotting, and assessment of expressions of interlukin-2 (IL-2), interferon-γ (IFN-γ), nuclear transcription factor-κB (NF-κB) p65, vascular endothelial growth factor (VEGF) and intercellular adhesion molecule-1 (ICAM-1). The allograft survival was significantly longer in group D than in group C (29.12±9.58 vs 9.67±2.16 days, P<0.05). UC treatment obviously reduced the expression levels of IL-2, IFN-γ, NF-κBp65, ICAM-1 and VEGF and increased inhibitory kappa B alpha (IκB-α) expression in the grafts, where no obvious inflammatory cell infiltration or corneal neovascularization was found. As a NF-κB inhibitor, ursolic acid can prevent corneal neovascularization and corneal allograft rejection to promote graft survival in rats following orthotopic corneal allograft transplantation.

  9. Fresh-frozen Complete Extensor Mechanism Allograft versus Autograft Reconstruction in Rabbits

    PubMed Central

    Chen, Guanyin; Zhang, Hongtao; Ma, Qiong; Zhao, Jian; Zhang, Yinglong; Fan, Qingyu; Ma, Baoan

    2016-01-01

    Different clinical results have been reported in the repair of extensor mechanism disruption using fresh-frozen complete extensor mechanism (CEM) allograft, creating a need for a better understanding of fresh-frozen CME allograft reconstruction. Here, we perform histological and biomechanical analyses of fresh-frozen CEM allograft or autograft reconstruction in an in vivo rabbit model. Our histological results show complete incorporation of the quadriceps tendon into the host tissues, patellar survival and total integration of the allograft tibia, with relatively fewer osteocytes, into the host tibia. Vascularity and cellularity are reduced and delayed in the allograft but exhibit similar distributions to those in the autograft. The infrapatellar fat pad provides the main blood supply, and the lowest cellularity is observed in the patellar tendon close to the tibia in both the allograft and autograft. The biomechanical properties of the junction of quadriceps tendon and host tissues and those of the allograft patellar tendon are completely and considerably restored, respectively. Therefore, fresh-frozen CEM allograft reconstruction is viable, but the distal patellar tendon and the tibial block may be the weak links of the reconstruction. These findings provide new insight into the use of allograft in repairing disruption of the extensor mechanism. PMID:26911538

  10. Fresh-frozen Complete Extensor Mechanism Allograft versus Autograft Reconstruction in Rabbits.

    PubMed

    Chen, Guanyin; Zhang, Hongtao; Ma, Qiong; Zhao, Jian; Zhang, Yinglong; Fan, Qingyu; Ma, Baoan

    2016-02-25

    Different clinical results have been reported in the repair of extensor mechanism disruption using fresh-frozen complete extensor mechanism (CEM) allograft, creating a need for a better understanding of fresh-frozen CME allograft reconstruction. Here, we perform histological and biomechanical analyses of fresh-frozen CEM allograft or autograft reconstruction in an in vivo rabbit model. Our histological results show complete incorporation of the quadriceps tendon into the host tissues, patellar survival and total integration of the allograft tibia, with relatively fewer osteocytes, into the host tibia. Vascularity and cellularity are reduced and delayed in the allograft but exhibit similar distributions to those in the autograft. The infrapatellar fat pad provides the main blood supply, and the lowest cellularity is observed in the patellar tendon close to the tibia in both the allograft and autograft. The biomechanical properties of the junction of quadriceps tendon and host tissues and those of the allograft patellar tendon are completely and considerably restored, respectively. Therefore, fresh-frozen CEM allograft reconstruction is viable, but the distal patellar tendon and the tibial block may be the weak links of the reconstruction. These findings provide new insight into the use of allograft in repairing disruption of the extensor mechanism.

  11. Septic Arthritis After Anterior Cruciate Ligament Reconstruction: Clinical and Functional Outcomes Based on Graft Retention or Removal.

    PubMed

    Waterman, Brian R; Arroyo, William; Cotter, Eric J; Zacchilli, Michael A; Garcia, E'Stephan J; Owens, Brett D

    2018-03-01

    There remains a debate over whether to retain the index anterior cruciate ligament (ACL) graft in the setting of septic arthritis. To evaluate and compare clinical outcomes for the treatment of septic arthritis after ACL reconstruction (ACLR) in those with and without early graft retention. Case series; Level of evidence, 4. The Military Health System was queried for all ACLR procedures performed between 2007 and 2013. Inclusion criteria required active military status, primary ACLR with secondary septic arthritis, and minimum 24-month surveillance. Demographic, clinical, and surgical variables were evaluated using descriptive statistics and regression analysis for factors influencing selected outcomes. Of 9511 ACLR procedures, 31 (0.32%) were identified as having secondary septic arthritis requiring urgent arthroscopic irrigation and debridement and intravenous antibiotics (mean, 6.3 weeks). The majority (62%) were treated in the subacute (2 weeks to 2 months) setting. Index ACLR was performed with a hamstring autograft (n = 17, 55%), soft tissue allograft (n = 11, 35%), and patellar tendon autograft (n = 3, 10%). The graft was retained in 71% (n = 22) of patients, while 29% (n = 9) underwent early graft debridement. At a mean 26.9-month follow-up, 48% of patients (n = 15) had returned to the military. Graft removal was not predictive of return to active duty ( P = .29). The presence of postoperative complications, including symptomatic postinfection arthritis (22.6%) and arthrofibrosis (9.7%), was the only variable predictive of inability to return to duty (odds ratio, 27.5 [95% CI, 3.24-233.47]; P = .002). Seven of 9 patients who underwent graft debridement underwent revision ACLR, and all 7 had stable knees at final follow-up compared with 68% (15/22) in the graft retention group. Arthroscopic debridement with early graft removal and staged revision ACLR remains a viable option for restoring knee stability (100%), although the rate of return to active duty was

  12. Septic Arthritis After Anterior Cruciate Ligament Reconstruction: Clinical and Functional Outcomes Based on Graft Retention or Removal

    PubMed Central

    Waterman, Brian R.; Arroyo, William; Cotter, Eric J.; Zacchilli, Michael A.; Garcia, E’Stephan J.; Owens, Brett D.

    2018-01-01

    Background: There remains a debate over whether to retain the index anterior cruciate ligament (ACL) graft in the setting of septic arthritis. Purpose: To evaluate and compare clinical outcomes for the treatment of septic arthritis after ACL reconstruction (ACLR) in those with and without early graft retention. Study Design: Case series; Level of evidence, 4. Methods: The Military Health System was queried for all ACLR procedures performed between 2007 and 2013. Inclusion criteria required active military status, primary ACLR with secondary septic arthritis, and minimum 24-month surveillance. Demographic, clinical, and surgical variables were evaluated using descriptive statistics and regression analysis for factors influencing selected outcomes. Results: Of 9511 ACLR procedures, 31 (0.32%) were identified as having secondary septic arthritis requiring urgent arthroscopic irrigation and debridement and intravenous antibiotics (mean, 6.3 weeks). The majority (62%) were treated in the subacute (2 weeks to 2 months) setting. Index ACLR was performed with a hamstring autograft (n = 17, 55%), soft tissue allograft (n = 11, 35%), and patellar tendon autograft (n = 3, 10%). The graft was retained in 71% (n = 22) of patients, while 29% (n = 9) underwent early graft debridement. At a mean 26.9-month follow-up, 48% of patients (n = 15) had returned to the military. Graft removal was not predictive of return to active duty (P = .29). The presence of postoperative complications, including symptomatic postinfection arthritis (22.6%) and arthrofibrosis (9.7%), was the only variable predictive of inability to return to duty (odds ratio, 27.5 [95% CI, 3.24-233.47]; P = .002). Seven of 9 patients who underwent graft debridement underwent revision ACLR, and all 7 had stable knees at final follow-up compared with 68% (15/22) in the graft retention group. Conclusion: Arthroscopic debridement with early graft removal and staged revision ACLR remains a viable option for restoring knee

  13. Using pre-operative MRI to predict intraoperative hamstring graft size for anterior cruciate ligament reconstruction.

    PubMed

    Leiter, Jeff; Elkurbo, Mohamed; McRae, Sheila; Chiu, James; Froese, Warren; MacDonald, Peter

    2017-01-01

    Large variation in tendon size between individuals makes hamstring graft diameter for anterior cruciate ligament (ACL) reconstruction unpredictable. Inadequate graft diameter may necessitate an alternative source of tissue requiring pre-operative planning. The purpose of this study was to determine whether magnetic resonance image (MRI) measurements and clinical anthropometric data are predictive of hamstring tendon graft diameter. Data from 109 patients having ACL reconstruction with semitendinosus-gracilis (STGT) autograft were retrospectively evaluated. Cross-sectional area (CSA) of the gracilis tendon (GT) and semitendinosus tendon (ST) were determined from pre-operative MRI scans. Variables included pre-operative height, weight, body mass index (BMI), age and gender; and intra-operative graft diameter. Correlations between anthropometric variables, hamstring tendons CSA and intra-operative graft diameter were calculated. Multiple stepwise regression was performed to assess the predictive value of these variables to graft diameter. Sensitivity and specificity were calculated to evaluate the utility of MRI CSA measurements in accurately identifying inadequate graft diameter (<8 mm). All anthropometric variables were positively correlated with intraoperative graft diameter (p < 0.01). Semitendinosus-gracilis tendon CSA (p < 0.001) and STGT CSA and weight (p < 0.001) were significantly predictive models of graft diameter. Sensitivity and specificity were 79 and 74 %, respectively. The strongest indicators of a four-stranded STGT graft for primary ACL reconstruction were STGT CSA on MRI plus weight. Measurement of graft diameter can be performed pre-operatively via MRI to identify tendons that may be of inadequate size for ACL reconstruction. This can assist with surgical planning to determine the most appropriate graft choice. III.

  14. [Comparison of composite grafting of autoskin with acellular dermal matrix from different sources].

    PubMed

    Chen, Jin-Hui; Qi, Shun-Zhen; Sun, Hui-Chen; He, Zhan-Guo; Li, Hui; Zhu, Yu-Feng; Chen, Xing

    2003-10-01

    To compare the composite grafts of acellular dermal matrix (ADM) from different sources with autoskin. Six local white mini pigs were employed for the experiment. The pigs were randomly divided into four groups according to different skin grafts, i.e. A (human ADM with razor thin autoskin), B (porcine ADM with razor thin autoskin), C (razor thin autoskin only), and D (split thickness autoskin) as control. The survival rate, the contraction degree of the grafts, and the histological changes in grafting area were observed at 2, 4, 8, 12 and 24 hours after the operation. The grafted area in both A and B groups appeared smooth and elastic with satisfactory graft survival. The in growth of the host reparative cells such as fibroblast and vascular endothelium could be induced by composite grafts of different ADMs with skin grafting. The contraction areas in A and B groups seemed bigger than those in C and D groups. The tissue structure of grafting areas was similar to that of split thickness skin grafting area at 24 post-operation weeks. Combination of the homogenous and heterogeneous ADMs with autografts exhibited similar biological function during the observation period (24 weeks after operation). Xenogenous ADMs might have broader clinical applications.

  15. Time-sequential changes of differentially expressed miRNAs during the process of anterior lumbar interbody fusion using equine bone protein extract, rhBMP-2 and autograft

    NASA Astrophysics Data System (ADS)

    Chen, Da-Fu; Zhou, Zhi-Yu; Dai, Xue-Jun; Gao, Man-Man; Huang, Bao-Ding; Liang, Tang-Zhao; Shi, Rui; Zou, Li-Jin; Li, Hai-Sheng; Bünger, Cody; Tian, Wei; Zou, Xue-Nong

    2014-03-01

    The precise mechanism of bone regeneration in different bone graft substitutes has been well studied in recent researches. However, miRNAs regulation of the bone formation has been always mysterious. We developed the anterior lumbar interbody fusion (ALIF) model in pigs using equine bone protein extract (BPE), recombinant human bone morphogenetic protein-2 (rhBMP-2) on an absorbable collagen sponge (ACS), and autograft as bone graft substitute, respectively. The miRNA and gene expression profiles of different bone graft materials were examined using microarray technology and data analysis, including self-organizing maps, KEGG pathway and Biological process GO analyses. We then jointly analyzed miRNA and mRNA profiles of the bone fusion tissue at different time points respectively. Results showed that miRNAs, including let-7, miR-129, miR-21, miR-133, miR-140, miR-146, miR-184, and miR-224, were involved in the regulation of the immune and inflammation response, which provided suitable inflammatory microenvironment for bone formation. At late stage, several miRNAs directly regulate SMAD4, Estrogen receptor 1 and 5-hydroxytryptamine (serotonin) receptor 2C for bone formation. It can be concluded that miRNAs play important roles in balancing the inflammation and bone formation.

  16. Autologous distal clavicle versus autologous coracoid bone grafts for restoration of anterior-inferior glenoid bone loss: a biomechanical comparison.

    PubMed

    Petersen, Steve A; Bernard, Johnathan A; Langdale, Evan R; Belkoff, Stephen M

    2016-06-01

    Treating anterior glenoid bone loss in patients with recurrent shoulder instability is challenging. Coracoid transfer techniques are associated with neurologic complications and neuroanatomic alterations. The purpose of our study was to compare the contact area and pressures of a distal clavicle autograft with a coracoid bone graft for the restoration of anterior glenoid bone loss. We hypothesized that a distal clavicle autograft would be as effective as a coracoid graft. In 13 fresh-frozen cadaveric shoulder specimens, we harvested the distal 1.0 cm of each clavicle and the coracoid bone resection required for a Latarjet procedure. A compressive load of 440 N was applied across the glenohumeral joint at 30° and 60° of abduction, as well as 60° of abduction with 90° of external rotation. Pressure-sensitive film was used to determine normal glenohumeral contact area and pressures. In each specimen, we created a vertical, 25% anterior bone defect, reconstructed with distal clavicle (articular surface and undersurface) and coracoid bone grafts, and determined the glenohumeral contact area and pressures. We used analysis of variance for group comparisons and a Tukey post hoc test for individual comparisons (with P <.05 indicating a significant difference). The articular distal clavicle bone graft provided the lowest mean pressure in all testing positions. The coracoid bone graft provided the greatest contact area in all humeral positions, but the difference was not significant. An articular distal clavicle bone graft is comparable in glenohumeral contact area and pressures to an optimally placed coracoid bone graft for restoring glenoid bone loss. Basic Science Study; Biomechanics. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  17. Bracing can partially limit tibial rotation during stressful activities after anterior crucial ligament reconstruction with a hamstring graft.

    PubMed

    Giotis, D; Paschos, N K; Zampeli, F; Pappas, E; Mitsionis, G; Georgoulis, A D

    2016-09-01

    Hamstring graft has substantial differences with BPTB graft regarding initial mechanical strength, healing sequence, and vascularization, which may imply that a different approach during rehabilitation period is required. The purpose of this study was to investigate the influence of knee bracing on tibial rotation in ACL-reconstructed patients with a hamstring autograft during high loading activities. The hypothesis was that there would be a decrease in tibial rotation in the ACL-reconstructed braced knee as compared to the unbraced knee. Twenty male patients having undergone unilateral ACL reconstruction with a semitendinosus/gracilis autograft were assessed. Kinematic data were collected with an eight-camera optoelectronic system during two stressful tasks: (1) descending from a stair and subsequent pivoting; and (2) landing from a platform and subsequent pivoting. In each patient, three different experimental conditions were evaluated: (A) wearing a prophylactic brace (braced condition); (B) wearing a patellofemoral brace (sleeved condition); (C) without brace (unbraced condition). The intact knee without brace served as a control. Tibial rotation was significantly lower in the intact knee compared to all three conditions of the ACL-reconstructed knee (P≤0.01 for both tasks). Presence of a brace or sleeve resulted in lower tibial rotation than in the unbraced condition (p=0.003 for descending/pivot and P=0.0004 for landing/pivot). The braced condition resulted in lower rotation than the sleeved condition for descending/pivoting (P=0.031) while no differences were found for landing/pivoting (P=0.230). Knee bracing limited the excessive tibial rotation during pivoting under high loading activities in ACL-reconstructed knees with a hamstring graft. This partial restoration of normal kinematics may have a potential beneficial effect in patients recovering from ACL reconstruction with a hamstring autograft. Level III, case-control therapeutic study. Copyright

  18. Intercalary frozen autograft for reconstruction of malignant bone and soft tissue tumours.

    PubMed

    Zekry, Karem M; Yamamoto, Norio; Hayashi, Katsuhiro; Takeuchi, Akihiko; Higuchi, Takashi; Abe, Kensaku; Taniguchi, Yuta; Alkhooly, Ali Zein A A; Abd-Elfattah, Ahmed Saleh; Fouly, Ezzat H; Ahmed, Adel Refaat; Tsuchiya, Hiroyuki

    2017-07-01

    In 1999, we developed a technique using frozen autografts-tumour-containing bone treated with liquid nitrogen-for the reconstruction of malignant bone tumours. The purpose of this study was to evaluate the functional and oncological outcomes of frozen autografts for intercalary reconstruction of malignant bones and soft tissue tumours. This retrospective study was designed to assess 34 patients of mean age 35 (range, 6-79) years. The mean follow-up period was 62 (24-214) months. The median length of the frozen autografts was 138.4 ± 60.39 (50-290) mm. Postsurgically, 20 patients remained disease-free, seven patients survived with no evidence of disease, five patients were alive with disease, and two patients died of disease. The five- and ten-year survival rates of the frozen autografts were 91.2% and the mean International Society of Limb Salvage score was 90%. Complete bony union was achieved in 97% of the patients. There were five cases of nonunion, six cases of fracture, two cases of deep infection and four cases of local recurrence. Utilizing intercalary frozen autografts for patients with a nonosteolytic primary or secondary bone tumour without involvement of the subchondral bone is a good alternative treatment, because it is a straightforward biological technique and can provide excellent limb function.

  19. Evaluation of parathyroid autograft growth and function in hemodialysis patients

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Karsenty, G.; Petraglia, A.; Bourdeau, A.

    1986-07-01

    The aim of our study was to evaluate the function and growth of parathyroid tissue autografted into the forearm of hemodialysis patients using several presently available methods. In a dynamic study, the secretory function of autografted tissue was evaluated in seven patients using either zero calcium dialysate or calcium infusion. In an additional prospective study, seven patients had repeated determinations of plasma immunoreactive parathyroid hormone (iPTH) concentration on samples from both forearms, a radionuclide evaluation of autograft function using thallium-201 chloride, and real time ultrasonography. Light microscopy analysis was performed in two patients. The dynamic study demonstrated that induction ofmore » hypocalcemia was followed by an increase, and induction of hypercalcemia by a decrease in circulating iPTH in both forearms using three different radioimmunoassays similar to what has been reported for normal parathyroid tissue. A significant gradient (ie, greater than 2.0) of plasma iPTH concentration in samples from both forearms was observed in only three out of the seven patients of the prospective study. Two of these patients disclosed an increased uptake of /sup 201/TI chloride at the site of autografted tissue and had an echographically detectable mass. In both, hyperplastic parathyroid tissue was removed. At present, the remaining third patient does not have other features of recurrent hyperparathyroidism. In conclusion, autotransplanted parathyroid tissue of hemodialysis patients shows an adequate response to physiologic stimuli such as hypo- and hypercalcemia. Dynamic tests, therefore, appear to be a useful tool in the assessment of its function. In addition, radionuclide and echographic studies may be reliable adjuncts in the detection of marked parathyroid autograft hyperplasia.« less

  20. Feasibility of fabricating personalized 3D-printed bone grafts guided by high-resolution imaging

    NASA Astrophysics Data System (ADS)

    Hong, Abigail L.; Newman, Benjamin T.; Khalid, Arbab; Teter, Olivia M.; Kobe, Elizabeth A.; Shukurova, Malika; Shinde, Rohit; Sipzner, Daniel; Pignolo, Robert J.; Udupa, Jayaram K.; Rajapakse, Chamith S.

    2017-03-01

    Current methods of bone graft treatment for critical size bone defects can give way to several clinical complications such as limited available bone for autografts, non-matching bone structure, lack of strength which can compromise a patient's skeletal system, and sterilization processes that can prevent osteogenesis in the case of allografts. We intend to overcome these disadvantages by generating a patient-specific 3D printed bone graft guided by high-resolution medical imaging. Our synthetic model allows us to customize the graft for the patients' macro- and microstructure and correct any structural deficiencies in the re-meshing process. These 3D-printed models can presumptively serve as the scaffolding for human mesenchymal stem cell (hMSC) engraftment in order to facilitate bone growth. We performed highresolution CT imaging of a cadaveric human proximal femur at 0.030-mm isotropic voxels. We used these images to generate a 3D computer model that mimics bone geometry from micro to macro scale represented by STereoLithography (STL) format. These models were then reformatted to a format that can be interpreted by the 3D printer. To assess how much of the microstructure was replicated, 3D-printed models were re-imaged using micro-CT at 0.025-mm isotropic voxels and compared to original high-resolution CT images used to generate the 3D model in 32 sub-regions. We found a strong correlation between 3D-printed bone volume and volume of bone in the original images used for 3D printing (R2 = 0.97). We expect to further refine our approach with additional testing to create a viable synthetic bone graft with clinical functionality.

  1. Development of a long-term ovine model of cutaneous burn and smoke inhalation injury and the effects of early excision and skin autografting

    PubMed Central

    Yamamoto, Yusuke; Enkhbaatar, Perenlei; Sakurai, Hiroyuki; Rehberg, Sebastian; Asmussen, Sven; Ito, Hiroshi; Sousse, Linda E.; Cox, Robert A.; Deyo, Donald J.; Traber, Lillian D.; Traber, Maret G.; Herndon, David N.; Traber, Daniel L.

    2013-01-01

    Smoke inhalation injury frequently increases the risk of pneumonia and mortality in burn patients. The pathophysiology of acute lung injury secondary to burn and smoke inhalation is well studied, but long-term pulmonary function, especially the process of lung tissue healing following burn and smoke inhalation, has not been fully investigated. By contrast, early burn excision has become the standard of care in the management of major burn injury. While many clinical studies and small-animal experiments support the concept of early burn wound excision, and show improved survival and infectious outcomes, we have developed a new chronic ovine model of burn and smoke inhalation injury with early excision and skin grafting that can be used to investigate lung pathophysiology over a period of 3 weeks. Materials and methods Eighteen female sheep were surgically prepared for this study under isoflurane anesthesia. The animals were divided into three groups: an Early Excision group (20% TBSA, third-degree cutaneous burn and 36 breaths of cotton smoke followed by early excision and skin autografting at 24 h after injury, n = 6), a Control group (20% TBSA, third-degree cutaneous burn and 36 breaths of cotton smoke without early excision, n = 6) and a Sham group (no injury, no early excision, n = 6). After induced injury, all sheep were placed on a ventilator and fluid-resuscitated with Lactated Ringers solution (4 mL/% TBS/kg). At 24 h post-injury, early excision was carried out to fascia, and skin grafting with meshed autografts (20/1000 in., 1:4 ratio) was performed under isoflurane anesthesia. At 48 h post-injury, weaning from ventilator was begun if PaO2/FiO2 was above 250 and sheep were monitored for 3 weeks. Results At 96 h post-injury, all animals were weaned from ventilator. There are no significant differences in PaO2/FiO2 between Early Excision and Control groups at any points. All animals were survived for 3 weeks without infectious complication in Early Excision

  2. First experience using cultured epidermal autografts in Taiwan for burn victims of the Formosa Fun Coast Water Park explosion, as part of Japanese medical assistance.

    PubMed

    Matsumura, Hajime; Harunari, Nobuyuki; Ikeda, Hiroto

    2016-05-01

    On June 27, 2015, a flammable starch-based powder exploded at Formosa Fun Coast in Taipei, Taiwan, injuring 499 people, and more than 200 people were in critical condition with severe burns. Although a cultured epidermal autograft (CEA) was not approved or used in clinical practice, the Taiwan Food and Drug Administration requested a Japanese CEA manufacturer to donate CEA for the burn victims as part of international medical assistance. The authors cooperated in this project and participated in the patient selection, wound bed management for CEA, and technical assistance for CEA use. Here, we provide an overview of the project. Nine patients were enrolled, and two patients were excluded from the skin biopsy; seven skin biopsies were collected approximately 1 month after the disaster. The average TBSA% burned was 81.0%, and the mean age was 20.1 years. CEA was grafted in five patients; wound closure had been obtained in one patient, and one patient was severely ill at the time of grafting. The CEA was combined with a wide split auto mesh graft or patch graft. The mean re-epithelization rate at 4 weeks after the grafting was 84.2% by patient, and all of the patients survived. Although this project had many obstacles to overcome, CEA grafting was successful and contributed to wound closure and survival. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

  3. The Effect of Liquid Nitrogen on Bone Graft Survival.

    PubMed

    Sirinoglu, Hakan; Çilingir, Özlem Tuğçe; Çelebiler, Ozhan; Ercan, Feriha; Numanoglu, Ayhan

    2015-08-01

    Liquid nitrogen is used in medicine for cancer treatment and tissue preservation; however, bone viability after its application is controversial. This study aims to evaluate both the tissue viability and the clinical and histopathologic findings following liquid nitrogen application with different thawing techniques in rats. Mandibular bone grafts were taken from 45 Wistar rats and freezed in liquid nitrogen for 20 minutes. In the rapid-thawing technique (Rapid Thawing-1, Rapid Thawing-2), the grafts were held for 20 minutes in room temperature; in the slow-thawing technique (Slow Thawing-1, Slow Thawing-2), 20 minutes in -20°C, 20 minutes in +4°C, and 20 minutes in room temperature, respectively. In Rapid Thawing-2 and Slow Thawing-2 groups, autografts were implanted to their origin for 3 weeks and bone staining with India ink was performed and samples taken for histologic examination. The amount of cells and blood vessels and the density of bone canaliculi were significantly reduced in Rapid Thawing-1 and Slow Thawing-1 groups comparing to the Control group. However, the reduction rate was more significant in the Slow Thawing-1 group. Histomorphometric evaluation of the healing autografts after 3 weeks revealed that the decreased amounts of canaliculi were not changed in Slow Thawing-2 group. The study results demonstrated that bone tissue survives after liquid nitrogen treatment regardless of the performed thawing technique; however, slow thawing causes more tissue damage and metabolism impairment. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  4. Bone Grafts

    MedlinePlus

    ... allograft bone comes from donors who have died. Tissue banks screen these donors and disinfect and test the donated bone to make sure it is safe to use. If the transplanted bone comes ... an autograft. Autograft bone often comes from your ribs, hips or a leg.

  5. Considerations in the use of biologic grafts and alloplastic implants in facial plastic and reconstructive surgery.

    PubMed

    Boyce, R G; Toriumi, D M

    1992-01-01

    Surgical changes in the contour of soft tissue and bone of the craniomaxillofacial structures may require use of a biologic graft or alloplastic implant. Autologous materials are preferred; however, the harvesting procedure, donor site, and its associated morbidity are the disadvantages of using autografts. There are numerous types of alloplastic implants and they all differ in how they interact with host tissues. Factors such as implant texture, ability to integrate with host tissues, and rate of resorption all influence the overall success of different implants. In this article, we discuss some considerations in the use of biologic grafts and alloplastic implants in facial plastic and reconstructive surgery.

  6. Influence of 45S5 Bioactive Glass in A Standard Calcium Phosphate Collagen Bone Graft Substitute on the Posterolateral Fusion of Rabbit Spine.

    PubMed

    Pugely, Andrew J; Petersen, Emily B; DeVries-Watson, Nicole; Fredericks, Douglas C

    2017-01-01

    Spinal fusion surgery is an effective but costly treatment for select spinal pathology. Historically iliac crest bone graft (ICBG) has remained the gold standard for achieving successful arthrodesis. Given well-established morbidity autograft harvest, multiple bone graft replacements, void fillers, and extenders have been developed. The objective of this study was to evaluate the in vivo efficacy and safety of two mineralized collagen bone void filler materials similar in composition. Both bone void fillers were composed of hydroxyapatite (HA), tricalcium phosphate (TCP) and bovine collagen. The first test article (Bi-Ostetic bioactive glass foam or "45S5") also contained 45S5 bioactive glass particles while the second test article (Formagraft or "FG") did not. 45S5 and FG were combined with bone marrow aspirate and iliac crest autograft and compared to ICBG in an established posterolateral spine fusion rabbit model. Sixty-nine mature New Zealand White rabbits were divided into 3 test cohorts: ICBG, 45S5, and FG. A Posterolateral fusion model previous validated was utilized to assess fusion efficacy. The test groups were evaluated for spine fusion rate, new bone formation, graft resorption and inflammatory response using radiographic, μCT, biomechanical and histological endpoints at 4, 8 and 12 weeks following implantation. There were 4 clinical complications unrelated to the graft materials and were evenly split between groups (ICBG graft harvest complications; hind limb mobility, chronic pain) and were euthanized. These omissions did not affect the overall outcome of the study. Radiographic scoring of the fusion sites indicated a normal healing response in all test groups, with no adverse reactions and similar progressions of new bone formation observed over time. All groups demonstrated significantly less range of motion in both flexion/extension and lateral bending compared to normal not-fused controls, which supports fusion results observed in the other

  7. Percutaneously drilling through femoral head and neck fenestration combining with compacted autograft for early femoral head necrosis: A retrospective study.

    PubMed

    Li, Donghai; Xie, Xiaowei; Kang, Pengde; Shen, Bin; Pei, Fuxing; Wang, Changde

    2017-11-01

    The purpose of this study was to evaluate the clinical results, survivorship and quick rehabilitation effects of modified surgery of percutaneously drilling and decompression through femoral head and neck fenestration combined with compacted autograft for early femoral head necrosis. We conducted a retrospective cohort study with 83 hips performed percutaneous decompression through femoral head and neck fenestration (Modified group) combined with autogenous bone grafting for early ONFH. For comparison, another 90 hips treated with conventional core decompression with bone grafting (Control group). Median follow-up was 36 months (32-44 months). The length of incision, blood loss in operation, incision drainage, operation time and hospital stays in Modified group had better results than those in control group (P < 0.001). There were four cases in Modified group and five cases in control group had complications (P = 0.9). The VAS score and range of hip motion were better in Modified group during hospital stays summarily (P < 0.05). The average Harris score in modified group was higher than the control group at the first month (P = 0.005), while at other time of follow-up the two groups were with similar Harris scores (P > 0.05). There were 22 hips progressed to stage III in Modified group, while 23 hips progressed to stage III in control group (P = 0.89). The clinical success rate in Modified group were 86.7%, compared with that in control group (87.8%) ( P= 0.84). Percutaneous drilling and decompression through femoral head and neck fenestration combined with compacted autograft we reported showed an good surgical effect with a quick rehabilitation and had similar short-term effects compared with the conventional core decompression in treatment of early ONFH. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

  8. A comparative study of effect of autograft compared with allograft anterior cruciate ligament reconstruction on expressions of LOXs and MMPs

    PubMed Central

    Wang, Wei-Ming; Ma, Xiao-Jun; Huang, Shi-Bo; Ren, Liu-Bao

    2017-01-01

    The present study aimed to compare the effect of autograft or allograft anterior cruciate ligament (ACL) reconstruction on the expressions of lipoxygenases (LOXs) and matrix metalloproteinases (MMPs) in a New Zealand white rabbit model. New Zealand white rabbits were divided randomly into control, sham, autograft and allograft groups. At the 4th and 8th week after operation, biomechanical testing was performed to measure the primary length, cross-sectional area, maximum tensile load and stiffness of ACL, and HE staining was used to observe cell morphology and fibre alignment of ACL. At the 2nd, 4th and 8th week after operation, quantitative real-time PCR (qRT-PCR), Western blotting and immunohistochemistry were applied to detect LOXs and MMPs expressions, and expressions of adenomatous polyposis coli (APC)/Wnt signalling pathway-related proteins. At the 4th and 8th week after operation, the maximum tensile load and stiffness were higher in the autograft group than in the allograft group, and the values at the 8th week were higher than those at the 4th week after operation. The fibroblast proliferation in the allograft group was more significant than that in the autograft group. Compared with the control group, LOXs and MMPs expressions and the positive expression rates of LOXs and MMPs proteins were elevated, and the values in the allograft group were higher than those in the autograft group at all time points. At 8th week after operation, compared with the autograft group, Wnt expression was higher and APC expression was lower in the allograft group. Autograft and allograft ACL reconstruction can promote LOXs and MMPs expressions by activating the APC/Wnt signalling pathway. PMID:28275205

  9. Application of the cultured epidermal autograft "JACE(®") for treatment of severe burns: Results of a 6-year multicenter surveillance in Japan.

    PubMed

    Matsumura, Hajime; Matsushima, Asako; Ueyama, Masashi; Kumagai, Norio

    2016-06-01

    In the 1970s, Green et al. developed a method that involved culturing keratinocyte sheets and used for treatment of burns. Since then, the take rate of cultured epidermal autograft (CEA) onto fascia, granulation tissue, or allografts has been extensively reported, while that on an artificial dermis in a large case series is not. Moreover, the contribution of CEA to patient survival has not been analyzed in a multicenter study. We conducted a 6-year multicenter surveillance on the application of the CEA "JACE(®") for treatment of burns >30% total body surface area (TBSA) across 118 Japanese hospitals. This surveillance included 216 patients and 718 graft sites for efficacy analysis. The CEA take rate at 4 weeks after grafting was evaluated, and safety was monitored until 52 weeks. In addition, the survival curve obtained in this study and the data obtained from the Tokyo Burn Unit Association (TBUA) were compared. The mean CEA take rates at week 4 were 66% (sites) and 68% (patients), and the rate on the artificial dermis was 65% for 226 sites. CEA application combined with wide split-thickness auto or patch autograft increased the CEA take rate. On comparison with the data obtained from the TBUA, which included data on individuals with burns of the same severity, CEA application was found to contribute to patient survival until 7 weeks after burn. We reported the take rate of CEA based on a 6-year multicenter surveillance. From our results, we found that the application of CEA is a useful treatment for the patients with extensive burns. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  10. Autograft and pulmonary allograft performance in the second post-operative decade after the Ross procedure: insights from the Rotterdam Prospective Cohort Study.

    PubMed

    Mokhles, M Mostafa; Rizopoulos, Dimitris; Andrinopoulou, Eleni R; Bekkers, Jos A; Roos-Hesselink, Jolien W; Lesaffre, Emmanuel; Bogers, Ad J J C; Takkenberg, Johanna J M

    2012-09-01

    The objective of the present study was to report our ongoing prospective cohort of autograft recipients with up to 21 years of follow-up. All consecutive patients (n = 161), operated between 1988 and 2010, were analysed. Mixed-effects models were used to assess changes in echocardiographic measurements (n = 1023) over time in both the autograft and the pulmonary allograft. The mean patient age was 20.9 years (range 0.05-52.7)-66.5% were male. Early mortality was 2.5% (n = 4), and eight additional patients died during a mean follow-up of 11.6 ± 5.7 years (range 0-21.5). Patient survival was 90% [95% confidence interval (CI), 78-95] up to 18 years. During the follow-up, 57 patients required a re-intervention related to the Ross operation. Freedom from autograft reoperation and allograft re-intervention was 51% (95% CI 38-63) and 82% (95% CI 71-89) after 18 years, respectively. No major changes were observed over time in autograft gradient, and allograft gradient and regurgitation. An initial increase of sinotubular junction and aortic anulus diameter was observed in the first 5 years after surgery. The only factor associated with an increased autograft reoperation rate was pre-operative pure aortic regurgitation (AR) (hazard ratio 1.88; 95% CI 1.04-3.39; P= 0.037). We observed good late survival in patients undergoing autograft procedure without reinforcement techniques. However, over half of the autografts failed prior to the end of the second decade. The reoperation rate and the results of echocardiographic measurements over time underline the importance of careful monitoring especially in the second decade after the initial autograft operation and in particular in patients with pre-operative AR.

  11. Iliac crest bone graft: a 23-years hystory of infection at donor site in vertebral arthrodesis and a review of current bone substitutes.

    PubMed

    Babbi, L; Barbanti-Brodano, G; Gasbarrini, A; Boriani, S

    2016-11-01

    This is an exemplary case report underlining a relevant morbidity which could be associated to the use of autologous iliac crest bone graft (ICBG) for spine fusion. Starting from 1990, a 25-years-old woman underwent two subsequent surgical treatments for non-Hodgkin lymphoma vertebral localizations. In the second surgery, arthrodesis was obtained with autograft through right posterior iliac crest osteotomy. During the chemotherapy treatment following the surgery, the patient suffered from infection at posterior iliac crest scar, the site of previous graft, caused by methicillin-resistant Staphylococcus aureus. She was subjected to surgical debridement and specific antibiotic treatment with local healing and phlogosis index reduction. Chemotherapy protocol was concluded and the patient healed with definitive lymphoma remission. After 22 years the patient had a relapse of donor site infection, requiring a new antibiotic therapy and a new surgical debridement. The relapsed infection at donor site lasted for a long period, more than one year, despite of specific care. It finally healed after another accurate surgical debridement and postoperative antibiotic therapy. This case report underlines the possible consequences on the patient's quality of life of a long-term disease affecting the iliac crest bone graft donor site. Literature concerning alternatives to autograft for spine fusion is also reviewed.

  12. Free tarsomarginal graft for large congenital coloboma repair in patients with Tessier number 10 clefts.

    PubMed

    Fu, Yao; Shao, Chunyi; Lu, Wenjuan; Li, Jin; Fan, Xianqun

    2016-08-01

    The aim of this study was to evaluate the long-term outcome when a free tarsomarginal graft is used to repair a large congenital coloboma in patients with a Tessier number 10 cleft. This was a retrospective, interventional case series. The medical records were reviewed for five children (six eyes) diagnosed as having Tessier number 10 cleft with large upper eyelid defects and symblepharon. These children were referred to the Department of Ophthalmology of Shanghai Ninth People's Hospital, between May 2007 and December 2012. Reconstructive techniques included repair of the upper eyelid defect with a free tarsomarginal graft taken from the lower eyelid, and reconstruction of the conjunctival fornix by using a conjunctival autograft after symblepharon lysis. All the children were followed up for more than 2 years. Postoperative upper eyelid contour, viability and function for corneal protection, and recurrence of symblepharon were assessed. A one-stage reconstruction procedure was used in all children. All reconstructed eyelids achieved a surgical goal of providing corneal protection and improved cosmesis, with marked improvement of exposure keratopathy and no associated lagophthalmos. Adequate reconstruction of the upper fornix was obtained, and there was no obvious recurrence of symblepharon. A free tarsomarginal graft is beneficial and seems to be an adequate method for reconstruction of large eyelid defects in children with a Tessier number 10 cleft. Symblepharon lysis with a conjunctival autograft for reconstruction of the ocular surface can be performed at the same time as eyelid repair as a one-stage procedure. Copyright © 2016. Published by Elsevier Ltd.

  13. Specific Biomimetic Hydroxyapatite Nanotopographies Enhance Osteoblastic Differentiation and Bone Graft Osteointegration

    PubMed Central

    Loiselle, Alayna E.; Wei, Lai; Faryad, Muhammad; Paul, Emmanuel M.; Lewis, Gregory S.; Gao, Jun; Lakhtakia, Akhlesh

    2013-01-01

    Impaired healing of cortical bone grafts represents a significant clinical problem. Cadaveric bone grafts undergo extensive chemical processing to decrease the risk of disease transmission; however, these processing techniques alter the bone surface and decrease the osteogenic potential of cells at the healing site. Extensive work has been done to optimize the surface of bone grafts, and hydroxyapatite (HAP) and nanotopography both increase osteoblastic differentiation. HAP is the main mineral component of bone and can enhance osteoblastic differentiation and bone implant healing in vivo, while nanotopography can enhance osteoblastic differentiation, adhesion, and proliferation. This is the first study to test the combined effects of HAP and nanotopographies on bone graft healing. With the goal of identifying the optimized surface features to improve bone graft healing, we tested the hypothesis that HAP-based nanotopographic resurfacing of bone grafts improves integration of cortical bone grafts by enhancing osteoblastic differentiation. Here we show that osteoblastic cells cultured on processed bones coated with specific-scale (50–60 nm) HAP nanotopographies display increased osteoblastic differentiation compared to cells on uncoated bone, bones coated with poly-l-lactic acid nanotopographies, or other HAP nanotopographies. Further, bone grafts coated with 50–60-nm HAP exhibited increased formation of new bone and improved healing, with mechanical properties equivalent to live autografts. These data indicate the potential for specific HAP nanotopographies to not only increase osteoblastic differentiation but also improve bone graft incorporation, which could significantly increase patient quality of life after traumatic bone injuries or resection of an osteosarcoma. PMID:23510012

  14. Stage-two surgery using collagen soft tissue grafts: clinical cases and ultrastructural analysis.

    PubMed

    Fischer, Kai R; Fickl, Stefan; Mardas, Nikos; Bozec, Laurent; Donos, Nikolaos

    2014-01-01

    To present the application of two different soft tissue grafts around dental implants during stage-two surgery. Furthermore, the ultrastructure of these materials is shown and discussed using scanning electron microscopy (SEM). Although soft tissue autografts may be currently regarded as the gold standard, harvesting of these grafts might lead to higher morbidity, longer chair time, and intra-/postoperative complications at the donor site. New developments in collagen scaff olds have provided an alternative to successfully replace autologous grafts in clinical practice. The SEM pictures clearly show the different composition of a bilayer scaff old (collagen matrix, CM) and a porcine acellular dermal matrix (ADM). These distinctive properties lead to different possible indications. Within the presented cases, ADM was used to augment the ridge contour and was placed into a buccal pouch to achieve complete coverage and an uneventful closed healing. On the other side, CM was left exposed to the oral cavity to successfully gain keratinized mucosa around and between two dental implants.

  15. Prognostic significance of chemotherapy-induced necrosis in osteosarcoma patients receiving pasteurized autografts

    PubMed Central

    Joo, Min Wook; Kang, Yong Koo; Yoo, Chang-Young; Cha, Sung Ho

    2017-01-01

    Background Among various reconstruction methods after wide excision for osteosarcoma, pasteurized autograft is often preferred. While the whole area of the tumor can be assessed for chemotherapy-induced necrosis, one of the important prognostic factors, in other reconstructive techniques, only a portion removed from a wide-resection specimen is available when using pasteurized autograft method. The assessment, therefore, may be unreliable. We analyzed the prognostic significance of the chemotherapy-induced necrosis in osteosarcoma patients who underwent reconstruction with pasteurized autografts. Patients and methods We reviewed the records of osteosarcoma patients who underwent treatment in our institution from 1998 to 2013. Cases of reconstruction with pasteurized autografts were defined as the patient group, and the same number of patients who underwent other reconstruction methods served as controls. Chemotherapy-induced necrosis was evaluated for removed extra-osseous and curetted intramedullary tumor tissues. Results A total of 22 patients were identified; the median age was 15.5 years, and there were 12 males. The most common tumor location was the distal femur. The most common histological subtype was osteoblastic. Median size was 8.1 cm. Disease status was stage IIB in 13 patients and IIA in 9. Median follow-up was 76 months. No differences between the patient and control groups were observed in potential prognostic factors, overall survival, metastasis-free survival, or recurrence-free survival. Univariate analyses demonstrated that histological response was a significant prognostic factor for metastasis-free survival and also significant for recurrence-free survival. Conclusion Chemotherapy-induced necrosis grading, using only available tumor tissues, could be a prognostic factor for osteosarcoma patients receiving pasteurized autografts for reconstructive surgery. PMID:28196121

  16. Free Gingival Graft versus Mucograft: Histological Evaluation

    PubMed Central

    Menceva, Zaklina; Dimitrovski, Oliver; Popovska, Mirjana; Spasovski, Spiro; Spirov, Vancho; Petrushevska, Gordana

    2018-01-01

    INTRODUCTION: The correction of the gingival recession is of esthetical and functional significance, but the tissue regeneration can only be confirmed by a histological examination. AIM: This study aims to make a comparison between the free gingival graft and the autograft. MATERIAL AND METHODS: This study included 24 patients with single and multiple gingival recessions. Twelve patients were treated with a free gingival graft and the other twelve with a micrograft. Six months after the surgical procedure, a micro-punch biopsy of the transplantation area was performed. The tissue was histologically evaluated, graded in 4 categories: immature, mature, fragmented and edematous collagen tissue. The elastic fibres were also examined and graded in three categories: with a normal structure, fragmented rare and fragmented multiplied. RESULTS: Regarding the type of collagen tissue that was present, there was a significant difference between the two groups of patients, with a larger number of patients treated with a micrograft showing a presence of mature tissue, compared to the patients treated with a free gingival graft. A larger number of patients in both of the groups displayed elastic fibres with a rare fragmented structure; 33.3% of the patients showed a normal structure; 50% demonstrated a normal structure. CONCLUSION: The patients treated with a free gingival graft showed a larger presence of fragmented collagen tissue and fragmented elastic fibres, whereas a mature tissue was predominantly present in the surgical area where a Geistlich Mucograft was placed. PMID:29731940

  17. Foreskin-isolated keratinocytes provide successful extemporaneous autologous paediatric skin grafts.

    PubMed

    Mcheik, Jiad N; Barrault, Christine; Pedretti, Nathalie; Garnier, Julien; Juchaux, Franck; Levard, Guillaume; Morel, Franck; Lecron, Jean-Claude; Bernard, François-Xavier

    2016-03-01

    Severe burns in children are conventionally treated with split-thickness skin autografts or epidermal sheets. However, neither early complete healing nor quality of epithelialization is satisfactory. An alternative approach is to graft isolated keratinocytes. We evaluated paediatric foreskin and auricular skin as donor sources, autologous keratinocyte transplantation, and compared the graft efficiency to the in vitro capacities of isolated keratinocytes to divide and reconstitute epidermal tissue. Keratinocytes were isolated from surgical samples by enzymatic digestion. Living cell recovery, in vitro proliferation and epidermal reconstruction capacities were evaluated. Differentiation status was analysed, using qRT-PCR and immunolabelling. Eleven children were grafted with foreskin-derived (boys) or auricular (girls) keratinocyte suspensions dripped onto deep severe burns. The aesthetic and functional quality of epithelialization was monitored in a standardized way. Foreskin keratinocyte graft in male children provides for the re-epithelialization of partial deep severe burns and accelerates wound healing, thus allowing successful wound closure, and improves the quality of scars. In accordance, in vitro studies have revealed a high yield of living keratinocyte recovery from foreskin and their potential in terms of regeneration and differentiation. We report a successful method for grafting paediatric males presenting large severe burns through direct spreading of autologous foreskin keratinocytes. This alternative method is easy to implement, improves the quality of skin and minimizes associated donor site morbidity. In vitro studies have highlighted the potential of foreskin tissue for graft applications and could help in tissue selection with the prospect of grafting burns for girls. Copyright © 2013 John Wiley & Sons, Ltd.

  18. Free bone graft reconstruction of irradiated facial tissue: Experimental effects of basic fibroblast growth factor stimulation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eppley, B.L.; Connolly, D.T.; Winkelmann, T.

    1991-07-01

    A study was undertaken to evaluate the potential utility of basic fibroblast growth factor in the induction of angiogenesis and osseous healing in bone previously exposed to high doses of irradiation. Thirty New Zealand rabbits were evaluated by introducing basic fibroblast growth factor into irradiated mandibular resection sites either prior to or simultaneous with reconstruction by corticocancellous autografts harvested from the ilium. The fate of the free bone grafts was then evaluated at 90 days postoperatively by microangiographic, histologic, and fluorochrome bone-labeling techniques. Sequestration, necrosis, and failure to heal to recipient osseous margins was observed both clinically and histologically inmore » all nontreated irradiated graft sites as well as those receiving simultaneous angiogenic stimulation at the time of graft placement. No fluorescent activity was seen in these graft groups. In the recipient sites pretreated with basic fibroblast growth factor prior to placement of the graft, healing and reestablishment of mandibular contour occurred in nearly 50 percent of the animals. Active bone formation was evident at cortical margins adjacent to the recipient sites but was absent in the more central cancellous regions of the grafts.« less

  19. Matched Comparison of Fusion Rates between Hydroxyapatite Demineralized Bone Matrix and Autograft in Lumbar Interbody Fusion.

    PubMed

    Kim, Dae Hwan; Lee, Nam; Shin, Dong Ah; Yi, Seong; Kim, Keung Nyun; Ha, Yoon

    2016-07-01

    To compare the fusion rate of a hydroxyapatite demineralized bone matrix (DBM) with post-laminectomy acquired autograft in lumbar interbody fusion surgery and to evaluate the correlation between fusion rate and clinical outcome. From January 2013 to April 2014, 98 patients underwent lumbar interbody fusion surgery with hydroxyapatite DBM (HA-DBM group) in our institute. Of those patients, 65 received complete CT scans for 12 months postoperatively in order to evaluate fusion status. For comparison with autograft, we selected another 65 patients who underwent lumbar interbody fusion surgery with post-laminectomy acquired autograft (Autograft group) during the same period. Both fusion material groups were matched in terms of age, sex, body mass index (BMI), and bone mineral density (BMD). To evaluate the clinical outcomes, we analyzed the results of visual analogue scale (VAS), Oswestry Disability Index (ODI), and Short Form Health Survey (SF-36). We reviewed the CT scans of 149 fusion levels in 130 patients (HA-DBM group, 75 levels/65 patients; Autograft group, 74 levels/65 patients). Age, sex, BMI, and BMD were not significantly different between the groups (p=0.528, p=0.848, p=0.527, and p=0.610, respectively). The HA-DBM group showed 39 of 75 fused levels (52%), and the Autograft group showed 46 of 74 fused levels (62.2%). This difference was not statistically significant (p=0.21). In the HA-DBM group, older age and low BMD were significantly associated with non-fusion (61.24 vs. 66.68, p=0.027; -1.63 vs. -2.29, p=0.015, respectively). VAS and ODI showed significant improvement after surgery when fusion was successfully achieved in both groups (p=0.004, p=0.002, HA-DBM group; p=0.012, p=0.03, Autograft group). The fusion rates of the hydroxyapatite DBM and Autograft groups were not significantly different. In addition, clinical outcomes were similar between the groups. However, older age and low BMD are risk factors that might induce non-union after surgery with

  20. Matched Comparison of Fusion Rates between Hydroxyapatite Demineralized Bone Matrix and Autograft in Lumbar Interbody Fusion

    PubMed Central

    Kim, Dae Hwan; Lee, Nam; Shin, Dong Ah; Yi, Seong; Kim, Keung Nyun

    2016-01-01

    Objective To compare the fusion rate of a hydroxyapatite demineralized bone matrix (DBM) with post-laminectomy acquired autograft in lumbar interbody fusion surgery and to evaluate the correlation between fusion rate and clinical outcome. Methods From January 2013 to April 2014, 98 patients underwent lumbar interbody fusion surgery with hydroxyapatite DBM (HA-DBM group) in our institute. Of those patients, 65 received complete CT scans for 12 months postoperatively in order to evaluate fusion status. For comparison with autograft, we selected another 65 patients who underwent lumbar interbody fusion surgery with post-laminectomy acquired autograft (Autograft group) during the same period. Both fusion material groups were matched in terms of age, sex, body mass index (BMI), and bone mineral density (BMD). To evaluate the clinical outcomes, we analyzed the results of visual analogue scale (VAS), Oswestry Disability Index (ODI), and Short Form Health Survey (SF-36). Results We reviewed the CT scans of 149 fusion levels in 130 patients (HA-DBM group, 75 levels/65 patients; Autograft group, 74 levels/65 patients). Age, sex, BMI, and BMD were not significantly different between the groups (p=0.528, p=0.848, p=0.527, and p=0.610, respectively). The HA-DBM group showed 39 of 75 fused levels (52%), and the Autograft group showed 46 of 74 fused levels (62.2%). This difference was not statistically significant (p=0.21). In the HA-DBM group, older age and low BMD were significantly associated with non-fusion (61.24 vs. 66.68, p=0.027; -1.63 vs. -2.29, p=0.015, respectively). VAS and ODI showed significant improvement after surgery when fusion was successfully achieved in both groups (p=0.004, p=0.002, HA-DBM group; p=0.012, p=0.03, Autograft group). Conclusion The fusion rates of the hydroxyapatite DBM and Autograft groups were not significantly different. In addition, clinical outcomes were similar between the groups. However, older age and low BMD are risk factors that might

  1. ACL reconstruction using bone-patella tendon-bone autograft: press-fit technique vs. interference screw fixation.

    PubMed

    Sarzaeem, M M; Najafi, F; Razi, M; Najafi, M A

    2014-07-01

    The gold standard in ACL reconstructions has been the bone-patellar tendon-bone autograft fixed with interference screws. This prospective, randomized clinical trial aimed to compare two methods of fixation for BPTB grafts: press-fit fixation vs. interference screw, over a 12-month follow-up interval. 158 patients with an average age of 29.8 years, between 2011 and 2012, were treated for torn ACL. 82 patients underwent reconstruction with BPTB autograft with a press fit fixation technique, and in 76 cases an interference screw was used. At the time of final follow-up, 71 patients in press-fit group and 65 patients in interference screw group were evaluated in terms of return to pre-injury activity level, pain, knee stability, range of motion, IKDC score and complications. At 12-month follow-up, 59 (83 %) and 55 (85 %) in press-fit and screw group, respectively had good-to-excellent IKDC score (p > 0.05). The mean laxity assessed using a KT-1000 arthrometer improved to 2.7 and 2.5 mm in press-fit and screw group, respectively. Regarding Lachman and pivot shift test, there was a statistically significant improvement in the integrity of the ACL in both the groups, but no significant differences was noted between groups. There were no significant differences in terms of femur circumference difference, effusion, knee range of motion, pain and complications. The press-fit technique is an efficient procedure. Its outcome was comparable with the interference screw group. Furthermore it has unlimited bone-to-bone healing, no need for removal of hardware, ease for revision and cost effectiveness.

  2. Co-Graft of Acellular Dermal Matrix and Autogenous Microskin in a Child with Extensive Burns

    PubMed Central

    Chen, X.L.; Xia, Z.F.; Fang, L.S.; Wang, Y.J.; Wang, C.H.

    2008-01-01

    Summary A 6-yr-old boy was the victim of a burns accident in a public bathhouse. The burns involved the face, neck, upper and lower extremities, anterior and posterior trunk, and both buttocks, covering 72% of the total body surface area (TBSA). The lesions in the lower extremities and parts of the right upper extremity were deep partial-thickness, comprising 40% TBSA. On day 5 post-burn, the lesions in both lower extremities were excised to the extent of the fascia under general anaesthesia. Meshed J1 Jayya Acellular Dermis®, a kind of acellular allodermal (ADM) matrix, was then placed on the left knee joint. The right knee joint served as control. The wounds in both lower extremities were then overlaid with microskin autografting. At 19 days post-application, the lesions in both lower extremities had almost completely resurfaced. Follow-up at six months revealed well-healed and stable skin of acellular ADM and microskin autografts on the left knee. However, the skin of the right knee was unstable and there was a chronic residual ulcer. Both legs showed some significant hypertrophic scars. The left knee joint (acellular ADM grafted site) showed mild contractures, while the right knee joint developed a significant contracture. The "skin" of the co-graft covered site appeared thicker and more elastic. The movement range of the left knee joint was much larger than that of the right knee joint. These results suggest that co-graft of acellular dermal matrix and autogenous microskin may be an effective way to repair this functional site in children with extensive burns and to improve the functional and cosmetic results. PMID:21991120

  3. [Tibio-Calcaneal Arthrodesis with Vertically Placed Tricortical Bone Graft after Traumatic Talar Extrusion - a Case Report].

    PubMed

    Popelka, V; Zamborský, R

    2017-01-01

    The aim of this publication is to present a case report of a 38-year-old patient with traumatic astragalectomy and resultant foot reconstruction surgery using a combination of talus compensation by vertically placed tricortical autograft and pantalar arthrodesis with a retrograde calcaneotibial nail (hindfoot nail). The advantage of this treatment is based on a solid, stable osteosynthesis, while maintaining the length of the limb. Key words: traumatic talar extrusion, tibiocalcaneal arthrodesis, hindfoot nail, bone graft, pantalar arthrodesis.

  4. Surgical Treatment for Failure of Repair of Patellar and Quadriceps Tendon Rupture With Ipsilateral Hamstring Tendon Graft.

    PubMed

    Maffulli, Nicola; Papalia, Rocco; Torre, Guglielmo; Denaro, Vincenzo

    2017-03-01

    Tears of the patellar and quadriceps tendon are common in the active population, especially in athletes. At present, several techniques for surgical repair and reconstruction are available. When reruptures occur, a reconstruction is mandatory. In the present paper, we describe a surgical technique for patellar and quadriceps tendon reconstruction using ipsilateral hamstring autograft. After routine hamstring tendon harvesting, the tendon ends are prepared using a whip stitch. A transverse tunnel is drilled in the midportion of the patella, the hamstring graft is passed through the patella, and firmly secured to the patellar tunnel openings with sutures. The details of the technique are fully described. Autologous ipsilateral hamstring tendon grafts provide a secure sound means to manage these challenging injuries.

  5. Repair of sheep long bone cortical defects filled with COLLOSS, COLLOSS E, OSSAPLAST, and fresh iliac crest autograft.

    PubMed

    Huffer, William E; Benedict, James J; Turner, A S; Briest, Arne; Rettenmaier, Robert; Springer, Marco; Walboomers, X F

    2007-08-01

    COLLOSS and COLLOSS E are osteoinductive bone void fillers consisting of bone collagen and noncollagenous proteins from bovine and equine bone, respectively. The aim of this study was to compare COLLOSS, COLLOSS E, iliac bone autograft, sintered beta tricalcium phosphate (beta-TCP; OSSAPLAST), and COLLOSS E plus OSSAPLAST. Materials were placed for 4, 8, or 24 weeks in 5-mm cortical bone defects in sheep long bones. Histological sections in a plane perpendicular to the long axis of the bone were used to measure the total repair area (original defect plus callus) and the area of bone within the total repair area. The incidence of defect union was also evaluated. At 4 and 8 weeks, defects treated with COLLOSS and COLLOSS E with or without OSSAPLAST had total repair and bone areas equivalent to autograft, and larger than OSSAPLAST-treated defects. At 8 weeks, the incidence of defect union was higher in defects treated with autograft or COLLOSS E plus OSSAPLAST than in untreated defects. At 24 weeks, the incidence of union was 100% in all treatment groups and 0% in untreated defects. The incidence of union was related to the degree of remodeling between 8 and 24 weeks. This was greater in all treated than nontreated defects. In conclusion, COLLOSS and COLLOSS E were equivalent to each other and to autograft, and superior to beta-TCP, in this study model.

  6. Free conjunctival autograft in the management of advanced primary and recurrent pterygia.

    PubMed

    Seid, A; Bejiga, A

    2000-11-01

    To evaluate the outcome of free conjuctival autograft in patients with grades III and IV pterygia and to determine the post-operative recurrence rate. A prospective descriptive study. Menelik II Hospital, Addis Ababa, Ethiopia. Thirty four patients, 32 with primary and two with recurrent pterygia. A superficial Keratectomy extending beyond the corneal lesion all around and sufficiently deep to Bowman's layer to produce a perfectly clear cornea in the excised area followed by suture a free conjuctival autograft on the excised area. Improvement in visual acuity and recurrence rate of pterygia at follow up. Of the 32 patients followed up, the visual acuity remained the same on eight and improved in 24 cases. There were no intraoperative complications. Pterygia recurred in two patients between three and four months postoperatively. This study suggests that a free conjuctival autograft in the management of stage III and IV pterygia is a useful operation resulting in a very low recurrence rate of the pathology.

  7. Evaluation of the osteo-inductive potential of hollow three-dimensional magnesium-strontium substitutes for the bone grafting application.

    PubMed

    Li, Mei; Yang, Xuan; Wang, Weidan; Zhang, Yu; Wan, Peng; Yang, Ke; Han, Yong

    2017-04-01

    Regeneration of bone defects is a clinical challenge that usually necessitates bone grafting materials. Limited bone supply and donor site morbidity limited the application of autografting, and improved biomaterials are needed to match the performance of autografts. Osteoinductive materials would be the perfect candidates for achieving this task. Strontium (Sr) is known to encourage bone formation and also prevent osteoporosis. Such twin requirements have motivated researchers to develop Sr-substituted biomaterials for orthopedic applications. The present study demonstrated a new concept of developing biodegradable and hollow three-dimensional magnesium-strontium (MgSr) devices for grafting with their clinical demands. The microstructure and performance of MgSr devices, in vitro degradation and biological properties including in vitro cytocompatibility and osteoinductivity were investigated. The results showed that our MgSr devices exhibited good cytocompatibility and osteogenic effect. To further investigate the underlying mechanisms, RT-PCR and Western Blotting assays were taken to analyze the expression level of osteogenesis-related genes and proteins, respectively. The results showed that our MgSr devices could both up-regulate the genes and proteins expression of the transcription factors of Runt-related transcription factor 2 (RUNX2) and Osterix (OSX), as well as alkaline phosphatase (ALP), Osteopontin (OPN), Collagen I (COL I) and Osteocalcin (OCN) significantly. Taken together, our innovation presented in this work demonstrated that the hollow three-dimensional MgSr substitutes had excellent biocompatibility and osteogenesis and could be potential candidates for bone grafting for future orthopedic applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Labral reconstruction with iliotibial band autografts and semitendinosus allografts improves hip joint contact area and contact pressure: an in vitro analysis.

    PubMed

    Lee, Simon; Wuerz, Thomas H; Shewman, Elizabeth; McCormick, Frank M; Salata, Michael J; Philippon, Marc J; Nho, Shane J

    2015-01-01

    Labral reconstruction using iliotibial band (ITB) autografts and semitendinosus (Semi-T) allografts has recently been described in cases of labral deficiency. To characterize the joint biomechanics with a labrum-intact, labrum-deficient, and labrum-reconstructed acetabulum in a hip cadaveric model. The hypothesis was that labral resection would decrease contact area, increase contact pressure, and increase peak force, while subsequent labral reconstruction with ITB autografts or Semi-T allografts would restore these values toward the native intact labral state. Controlled laboratory study. Ten fresh-frozen human cadaveric hips were analyzed utilizing thin-film piezoresistive load sensors to measure contact area, contact pressure, and peak force (1) with the native intact labrum, (2) after segmental labral resection, and (3) after graft labral reconstruction with either ITB autografts or Semi-T allografts. Each specimen was examined at 20° of extension and 60° of flexion. Statistical analysis was conducted through 1-way analysis of variance with post hoc Games-Howell tests. For the ITB group, labral resection significantly decreased contact area (at 20°: 73.2%±5.38%, P=.0010; at 60°: 78.5%±6.93%, P=.0063) and increased contact pressure (at 20°: 106.7%±4.15%, P=.0387; at 60°: 103.9%±1.15%, P=.0428). In addition, ITB reconstruction improved contact area (at 20°: 87.2%±12.3%, P=.0130; at 60°: 90.5%±8.81%, P=.0079) and contact pressure (at 20°: 98.5%±5.71%, P=.0476; at 60°: 96.6%±1.13%, P=.0056) from the resected state. Contact pressure at 60° of flexion was significantly lower compared with the native labrum (P=.0420). For the Semi-T group, labral resection significantly decreased contact area (at 20°: 68.1%±12.57%, P=.0002; at 60°: 67.5%±6.70%, P=.0002) and increased contact pressure (at 20°: 105.3%±3.73%, P=.0304; at 60°: 106.8%±4.04%, P=.0231). Semi-T reconstruction improved contact area (at 20°: 87.9%±7.95%, P=.0087; at 60°: 92.9%±13

  9. Multiple arthroscopic debridement and graft retention in septic knee arthritis after ACL reconstruction: a prospective case-control study.

    PubMed

    Abdel-Aziz, Ahmed; Radwan, Yasser A; Rizk, Ahmed

    2014-01-01

    This study was undertaken to prospectively analyse, at a mean five-year follow-up, the clinical, functional, and radiographic outcomes in patients who developed postoperative acute septic knee arthritis following anterior cruciate ligament (ACL) reconstruction using hamstring autograft. We also assessed the effect of multiple arthroscopic debridement and graft retention on the functional outcomes in comparison with the matched control group. From a consecutive case series of 2,560 ACL-injured patients who were treated with arthroscopic ACL reconstruction, we report on 24 cases with postoperative septic knee arthritis. These patients were individually matched for age, sex, comorbidity, body mass index (BMI) and preinjury Tegner activity scale in a ratio of 1/1. Clinical, laboratory, synovial fluid analysis and culture were performed. Arthroscopic debridement and graft retention was done for all cases, in addition to antibiotic therapy i.v.. A detailed physical examination, KT1000 laxity testing, Lysholm knee score, Tegner activity level scale, International Knee Documentation Committee (IKDC), and Knee Injury and Osteoarthritis Outcome Score (KOOS) were completed. In all cases, treatment of infection was successful after a median of three (range one to six) repeated arthroscopic graft debridement and retention, in addition to antibiotic therapy i.v.. At an average of five years follow-up, two patients had over five millimetres manual maximum side-to-side difference in laxity. There were no significant differences between groups regarding Lysholm score, IKDC and KOOS. Median final Tegner activity score was 5.5 versus 7 in the control group (p = 0.004). Complications included graft rupture in three patients, loss of range of motion in five, Sudeck's atrophy in one and moderate joint narrowing in two. There were no recurrences of septic arthritis or bone infection. Graft retention seems not only possible but appropriate in view of the experience presented in this

  10. Conjunctival autografting combined with low-dose mitomycin C for prevention of primary pterygium recurrence.

    PubMed

    Frucht-Pery, Joseph; Raiskup, Frederic; Ilsar, Michael; Landau, David; Orucov, Faik; Solomon, Abraham

    2006-06-01

    To compare the clinical outcome of pterygium surgery combining intraoperative mitomycin C (MMC) with a free conjunctival autograft, with three other methods of pterygium surgery, including intraoperative MMC alone, conjunctival autograft alone, and bare sclera without adjunctive treatment. Interventional, randomized and in part nonrandomized, prospective, comparative study. setting: A university medical center department of ophthalmology. One hundred and twenty patients underwent pterygium excision surgery. These patients were divided into four treatment groups. In group 1 (30 patients), MMC, 0.2 mg/ml, was applied for three minutes. In group 2 (30 patients), conjunctival autografting was performed. Group 3 (30 patients) received sodium chloride 0.9% only, and group 4 (30 patients) underwent conjunctival autografting combined with one minute application of MMC, 0.2 mg/ml. Recurrence rates and complications. Pterygium recurred in two patients (6.6%) in group 1, in four patients (13.3%) in group 2, in 14 patients (46.6%) in group 3, and in none of the patients in group 4. chi(2) analysis revealed a significantly lower recurrence rate in group 4 compared with group 2 (P = .038) and with group 3 (P < .0001). Epithelialization of the wounds was complete within 14 days of surgery. No complications were demonstrated in any of the study groups except for one case of minor melting of the flap in group 4. This study indicates that pterygium excision with a free conjunctival autograft combined with intraoperative low-dose MMC is a safe and effective technique in pterygium surgery.

  11. A tissue engineering solution for segmental defect regeneration in load-bearing long bones.

    PubMed

    Reichert, Johannes C; Cipitria, Amaia; Epari, Devakara R; Saifzadeh, Siamak; Krishnakanth, Pushpanjali; Berner, Arne; Woodruff, Maria A; Schell, Hanna; Mehta, Manav; Schuetz, Michael A; Duda, Georg N; Hutmacher, Dietmar W

    2012-07-04

    The reconstruction of large defects (>10 mm) in humans usually relies on bone graft transplantation. Limiting factors include availability of graft material, comorbidity, and insufficient integration into the damaged bone. We compare the gold standard autograft with biodegradable composite scaffolds consisting of medical-grade polycaprolactone and tricalcium phosphate combined with autologous bone marrow-derived mesenchymal stem cells (MSCs) or recombinant human bone morphogenetic protein 7 (rhBMP-7). Critical-sized defects in sheep--a model closely resembling human bone formation and structure--were treated with autograft, rhBMP-7, or MSCs. Bridging was observed within 3 months for both the autograft and the rhBMP-7 treatment. After 12 months, biomechanical analysis and microcomputed tomography imaging showed significantly greater bone formation and superior strength for the biomaterial scaffolds loaded with rhBMP-7 compared to the autograft. Axial bone distribution was greater at the interfaces. With rhBMP-7, at 3 months, the radial bone distribution within the scaffolds was homogeneous. At 12 months, however, significantly more bone was found in the scaffold architecture, indicating bone remodeling. Scaffolds alone or with MSC inclusion did not induce levels of bone formation comparable to those of the autograft and rhBMP-7 groups. Applied clinically, this approach using rhBMP-7 could overcome autograft-associated limitations.

  12. Posterior glenoid bone grafting in total shoulder arthroplasty for osteoarthritis with severe posterior glenoid wear.

    PubMed

    Nicholson, Gregory P; Cvetanovich, Gregory L; Rao, Allison J; O'Donnell, Patrick

    2017-10-01

    Total shoulder arthroplasty (TSA) in cases with posterior wear can be addressed by eccentric reaming of the anterior glenoid or by augmenting the posterior glenoid with bone grafting or augmented glenoid implants. We report the results of TSA with posterior glenoid bone grafting (PGBG) with humeral head autograft in patients with shoulder osteoarthritis and severe posterior glenoid wear. A retrospective review of cases from 2004 to 2014 revealed 34 patients. Preoperative and postoperative radiographs were evaluated for glenoid version and humeral head subluxation as well as component loosening. Patient-reported outcomes were compared preoperatively and postoperatively. Complications and reoperations were also evaluated. Of the 34 patients, 28 (82.4%) were available at a minimum of 2 years' follow-up. PGBG corrected glenoid retroversion from -28° ± 4° preoperatively to -4° ± 2° (P < .001). Humeral head subluxation also improved after PGBG with respect to the scapular axis and to the midglenoid face (P < .001). Radiographic analysis revealed all PGBGs had incorporated. Radiographically, 3 patients (10.7%) had a total of 5 broken or displaced screws. In addition, 3 patients (10.7%) had a broken metal marker in the center peg of the glenoid component. No patients required component revision surgery by final follow-up. Only 1 reoperation occurred for capsular release. Patients showed significant improvements in all patient-reported outcomes. Patients undergoing primary TSA with humeral head autograft PGBG showed significant improvements in glenoid version, humeral head subluxation, patient-reported outcomes, and range of motion at an average of 4 years' follow-up. There was a low revision rate and a high rate of graft incorporation. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  13. Periosteal BMP2 activity drives bone graft healing.

    PubMed

    Chappuis, Vivianne; Gamer, Laura; Cox, Karen; Lowery, Jonathan W; Bosshardt, Dieter D; Rosen, Vicki

    2012-10-01

    Bone graft incorporation depends on the orchestrated activation of numerous growth factors and cytokines in both the host and the graft. Prominent in this signaling cascade is BMP2. Although BMP2 is dispensable for bone formation, it is required for the initiation of bone repair; thus understanding the cellular mechanisms underlying bone regeneration driven by BMP2 is essential for improving bone graft therapies. In the present study, we assessed the role of Bmp2 in bone graft incorporation using mice in which Bmp2 has been removed from the limb prior to skeletal formation (Bmp2(cKO)). When autograft transplantations were performed in Bmp2cKO mice, callus formation and bone healing were absent. Transplantation of either a vital wild type (WT) bone graft into a Bmp2(cKO) host or a vital Bmp2(cKO) graft into a WT host also resulted in the inhibition of bone graft incorporation. Histological analyses of these transplants show that in the absence of BMP2, periosteal progenitors remain quiescent and healing is not initiated. When we analyzed the expression of Sox9, a marker of chondrogenesis, on the graft surface, we found it significantly reduced when BMP2 was absent in either the graft itself or the host, suggesting that local BMP2 levels drive periosteal cell condensation and subsequent callus cell differentiation. The lack of integrated healing in the absence of BMP2 was not due to the inability of periosteal cells to respond to BMP2. Healing was achieved when grafts were pre-soaked in rhBMP2 protein, indicating that periosteal progenitors remain responsive in the absence of BMP2. In contrast to the requirement for BMP2 in periosteal progenitor activation in vital bone grafts, we found that bone matrix-derived BMP2 does not significantly enhance bone graft incorporation. Taken together, our data show that BMP2 signaling is not essential for the maintenance of periosteal progenitors, but is required for the activation of these progenitors and their subsequent

  14. Rabbit Calvarial Defect Model for Customized 3D-Printed Bone Grafts.

    PubMed

    Lee, Kang-Gon; Lee, Kang-Sik; Kang, Yu-Jeoung; Hwang, Jong-Hyun; Lee, Se-Hwan; Park, Sang-Hyug; Park, Yongdoo; Cho, Young-Sam; Lee, Bu-Kyu

    2018-05-01

    Bone graft materials are commonly used to regenerate various bone defects, but their application is often limited because of the complex defect shape in various clinical conditions. Hence, customized bone grafts using three-dimensional (3D) printing techniques have been developed. However, conventional simple bone defect models are limited for evaluating the benefits and manufacturing accuracy of 3D-printed customized bone grafts. Thus, the aim of the present study was to develop a complex-shaped bone defect model. We designed an 8-shaped bony defect that consists of two simple circles attached to the rabbit calvarium. To determine the critical-sized defect (CSD) of the 8-shaped defects, 5.6- and 7-mm-diameter trephine burs were tested, and the 7-mm-diameter bur could successfully create a CSD, which was easily reproducible on the rabbit calvarium. The rate of new bone formation was 28.65% ± 8.63% at 16 weeks following creation of the defect. To confirm its efficacy for clinical use, the 8-shaped defect was created on a rabbit calvarium and 3D computed tomography (CT) was performed. A stereolithography file was produced using the CT data, and a 3D-printed polycaprolactone graft was fabricated. Using our 8-shaped defect model, we were able to modify the tolerances of the bone graft and calvarial defect to fabricate a more precise bone graft. Customized characteristics of the bone graft were then used to improve the accuracy of the bone graft. In addition, we confirmed the fitting ability of the 3D-printed graft during implantation of the graft. Our 8-shaped defect model on the rabbit calvarium using a 7.0-mm trephine bur may be a useful CSD model for evaluating 3D-printed graft materials.

  15. Efficacy of Epidermal Skin Grafts Over Complex, Chronic Wounds in Patients With Multiple Comorbidities.

    PubMed

    Fearmonti, Regina M

    2016-07-01

    Epidermal skin grafting presents an alternative to traditional autografts since only epidermal skin is harvested from the donor site. Split-thickness skin grafts are associated with difficulties at the donor site, including excessive pain, delayed healing, fluid loss, and unsatisfactory cosmetic results - all exacerbated in patients with comorbidities. A new automated epidermal harvesting tool (CelluTome Epidermal Harvesting System, KCI, an Acelity company, San Antonio, TX) involves concurrent application of heat and suction to normal skin to produce epidermal grafts. This article outlines the author's experience using this automated epidermal harvesting tool to harvest epidermal grafts and apply them on 23 chronic lower extremity wounds of patients with multiple comorbidities. Vacuum and heat were applied until epidermal microdomes were formed (30-45 minutes); an epidermal microdome array was collected onto a transfer dressing and applied over the wound. The automated harvesting tool yielded viable epithelium with every use. In addition to the epidermal skin graft, 16 of 23 wounds (70%) received adjunctive wound treatment, including negative pressure wound therapy, hyperbaric oxygen therapy, and/or regenerative tissue matrix. The average reepithelialization rate was 88.1% during a mean follow-up period of 76.4 days; no use of an anesthetic/operating room was required for the procedure. All donor sites were completely healed within 2 weeks without complications or scarring. Epidermal skin grafting provided a simplified, office-based grafting option with no donor site morbidity, and assisted in closure or size reduction of chronic wounds in this series.

  16. In Vivo Evaluation of Electrospun Polycaprolactone Graft for Anterior Cruciate Ligament Engineering

    PubMed Central

    Arom, Gabriel A.; Nazemi, Azadeh N.; Yeranosian, Michael G.; Wu, Benjamin M.; McAllister, David R.

    2015-01-01

    The anterior cruciate ligament (ACL) is critical for the structural stability of the knee and its injury often requires surgical intervention. Because current reconstruction methods using autograft or allograft tissue suffer from donor-site morbidity and limited supply, there has been emerging interest in the use of bioengineered materials as a platform for ligament reconstruction. Here, we report the use of electrospun polycaprolactone (PCL) scaffolds as a candidate platform for ACL reconstruction in an in vivo rodent model. Electrospun PCL was fabricated and laser cut to facilitate induction of cells and collagen deposition and used to reconstruct the rat ACL. Histological analysis at 2, 6, and 12 weeks postimplantation revealed biological integration, minimal immune response, and the gradual infiltration of collagen in both the bone tunnel and intra-articular regions of the scaffold. Biomechanical testing demonstrated that the PCL graft failure load and stiffness at 12 weeks postimplantation (13.27±4.20N, 15.98±5.03 N/mm) increased compared to time zero testing (3.95±0.33N, 1.95±0.35 N/mm). Taken together, these results suggest that electrospun PCL serves as a biocompatible graft for ACL reconstruction with the capacity to facilitate collagen deposition. PMID:25412879

  17. In vivo evaluation of electrospun polycaprolactone graft for anterior cruciate ligament engineering.

    PubMed

    Petrigliano, Frank A; Arom, Gabriel A; Nazemi, Azadeh N; Yeranosian, Michael G; Wu, Benjamin M; McAllister, David R

    2015-04-01

    The anterior cruciate ligament (ACL) is critical for the structural stability of the knee and its injury often requires surgical intervention. Because current reconstruction methods using autograft or allograft tissue suffer from donor-site morbidity and limited supply, there has been emerging interest in the use of bioengineered materials as a platform for ligament reconstruction. Here, we report the use of electrospun polycaprolactone (PCL) scaffolds as a candidate platform for ACL reconstruction in an in vivo rodent model. Electrospun PCL was fabricated and laser cut to facilitate induction of cells and collagen deposition and used to reconstruct the rat ACL. Histological analysis at 2, 6, and 12 weeks postimplantation revealed biological integration, minimal immune response, and the gradual infiltration of collagen in both the bone tunnel and intra-articular regions of the scaffold. Biomechanical testing demonstrated that the PCL graft failure load and stiffness at 12 weeks postimplantation (13.27±4.20N, 15.98±5.03 N/mm) increased compared to time zero testing (3.95±0.33N, 1.95±0.35 N/mm). Taken together, these results suggest that electrospun PCL serves as a biocompatible graft for ACL reconstruction with the capacity to facilitate collagen deposition.

  18. Arthroscopic Anatomic Reconstruction of the Lateral Ligaments of the Ankle With Gracilis Autograft

    PubMed Central

    Guillo, Stéphane; Archbold, Pooler; Perera, Anthony; Bauer, Thomas; Sonnery-Cottet, Bertrand

    2014-01-01

    Lateral ankle sprains are common; if conservative treatment fails and chronic instability develops, stabilization surgery is indicated. Numerous surgical procedures have been described, but those that most closely reproduce normal ankle lateral ligament anatomy and kinematics have been shown to have the best outcomes. Arthroscopy is a common adjunct to open ligament surgery, but it is traditionally only used to improve the diagnosis and the management of any associated intra-articular lesions. The stabilization itself is performed open because standard anterior ankle arthroscopy provides only partial visualization of the anterior talofibular ligament from above and the calcaneofibular ligament attachments cannot be seen at all. However, lateral ankle endoscopy can provide a view of this area that is superior to open surgery. We have developed a technique of ankle endoscopy that enables anatomic positioning of the repair or fixation of the graft. In this article we describe a safe and reproducible arthroscopic anatomic reconstruction of the lateral ligaments of the ankle using a gracilis autograft. The aim of this procedure is to obtain a more physiological reconstruction while maintaining all the advantages of an arthroscopic approach. PMID:25473613

  19. Bone anchors or interference screws? A biomechanical evaluation for autograft ankle stabilization.

    PubMed

    Jeys, Lee; Korrosis, Sotiris; Stewart, Todd; Harris, Nicholas J

    2004-01-01

    Autograft stabilization uses free semitendinosus tendon grafts to anatomically reconstruct the anterior talofibular ligament. Study aims were to evaluate the biomechanical properties of Mitek GII anchors compared with the Arthrex Bio-Tenodesis Screw for free tendon reconstruction of the anterior talofibular ligament. There are no differences in load to failure and percentage specimen elongation at failure between the 2 methods. Controlled laboratory study using porcine models. Sixty porcine tendon constructs were failure tested. Re-creating the pull of the anterior talofibular ligament, loads were applied at 70 degrees to the bones. Thirty-six tendons were fixed to porcine tali and tested using a single pull to failure; 10 were secured with anchors and No. 2 Ethibond, 10 with anchors and FiberWire, 10 with screws and Fiberwire, and 6 with partially gripped screws. Cyclic preloading was conducted on 6 tendons fixed by anchors and on 6 tendons fixed by screws before failure testing. Two groups of 6 components fixed to the fibula were also tested. The talus single-pull anchor group produced a mean load of 114 N and elongation of 37% at failure. The talus single-pull screw group produced a mean load of 227 N and elongation of 22% at failure (P <.05). Cyclic preloading at 65% failure load before failure testing produced increases in load and decreases in elongation at failure. Partially gripped screws produced a load of 133 N and elongation of 30% at failure. The fibula model produced significant increases in load to failure for both. The human anterior talofibular ligament has loads of 139 N at failure with instability occurring at 20% elongation. Interference screw fixation produced significantly greater failure strength and less elongation at failure than bone anchors. The improved biomechanics of interference screws suggests that these may be more suited to in vivo reconstruction of the anterior talofibular ligament than are bone anchors.

  20. The Graft Bending Angle Can Affect Early Graft Healing After Anterior Cruciate Ligament Reconstruction: In Vivo Analysis With 2 Years' Follow-up.

    PubMed

    Tashiro, Yasutaka; Gale, Tom; Sundaram, Vani; Nagai, Kanto; Irrgang, James J; Anderst, William; Nakashima, Yasuharu; Tashman, Scott; Fu, Freddie H

    2017-07-01

    A high graft bending angle (GBA) after anterior cruciate ligament (ACL) reconstruction has been suggested to cause stress on the graft. Nevertheless, evidence about its effect on graft healing in vivo is limited. The signal intensity on magnetic resonance imaging (MRI) would be higher in the proximal region of the ACL graft, and higher signals would be correlated to a higher GBA. Descriptive laboratory study. Anatomic single-bundle ACL reconstruction was performed on 24 patients (mean age, 20 ± 4 years) using the transportal technique. A quadriceps tendon autograft with a bone plug was harvested. To evaluate graft healing, the signal/noise quotient (SNQ) was measured in 3 regions of interest (ROIs) of the proximal, midsubstance, and distal ACL graft using high-resolution MRI (0.45 × 0.45 × 0.70 mm), with decreased signals suggesting improved healing. Dynamic knee motion was examined during treadmill walking and running to assess the in vivo GBA. The GBA was calculated from the 3-dimensional angle between the graft and femoral tunnel vectors at each motion frame, based on tibiofemoral kinematics determined from dynamic stereo X-ray analysis. Graft healing and GBAs were assessed at 6 and 24 months postoperatively. Repeated-measures analysis of variance was used to compare the SNQ in the 3 ROIs at 2 time points. Pearson correlations were used to analyze the relationship between the SNQ and mean GBA during 0% to 15% of the gait cycle. The SNQ of the ACL graft in the proximal region was significantly higher than in the midsubstance ( P = .022) and distal regions ( P < .001) at 6 months. The SNQ in the proximal region was highly correlated with the GBA during standing ( R = 0.64, P < .001), walking ( R = 0.65, P = .002), and running ( R = 0.54, P = .015) but not in the other regions. At 24 months, signals in the proximal and midsubstance regions decreased significantly compared with 6 months ( P < .001 and P = .008, respectively), with no difference across the graft

  1. Second-degree burns with six etiologies treated with autologous noncultured cell-spray grafting.

    PubMed

    Esteban-Vives, Roger; Choi, Myung S; Young, Matthew T; Over, Patrick; Ziembicki, Jenny; Corcos, Alain; Gerlach, Jörg C

    2016-11-01

    Partial and deep partial-thickness burn wounds present a difficult diagnosis and prognosis that makes the planning for a conservative treatment versus mesh grafting problematic. A non-invasive treatment strategy avoiding mesh grafting is often chosen by practitioners based on their clinical and empirical evidence. However, a delayed re-epithelialization after conservative treatment may extend the patient's hospitalization period, increase the risk of infection, and lead to poor functional and aesthetic outcome. Early spray grafting, using non-cultured autologous cells, is under discussion for partial and deep partial-thickness wounds to accelerate the re-epithelialization process, reducing the healing time in the hospital, and minimizing complications. To address planning for future clinical studies on this technology, suitable indications will be interesting. We present case information on severe second-degree injuries after gas, chemical, electrical, gasoline, hot water, and tar scalding burns showing one patient per indication. The treatment results with autologous non-cultured cells, support rapid, uncomplicated re-epithelialization with aesthetically and functionally satisfying outcomes. Hospital stays averaged 7.6±1.6 days. Early autologous cell-spray grafting does not preclude or prevent simultaneous or subsequent traditional mesh autografting when indicated on defined areas of full-thickness injury. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  2. Clinical results of hamstring autografts in anterior cruciate ligament reconstruction: a comparison of femoral knot/press-fit fixation and interference screw fixation.

    PubMed

    Ho, Wei-Pin; Lee, Chian-Her; Huang, Chang-Hung; Chen, Chih-Hwa; Chuang, Tai-Yuan

    2014-07-01

    To compare the clinical outcomes of femoral knot/press-fit anterior cruciate ligament (ACL) reconstruction with conventional techniques using femoral interference screws. Among patients who underwent arthroscopic ACL reconstruction with hamstring autografts, 73 were treated with either a femoral knot/press-fit technique (40 patients, group A) or femoral interference screw fixation (33 patients, group B). The clinical results of the 2 groups were retrospectively compared. The inclusion criteria were primary ACL reconstruction in active patients. The exclusion criteria were fractures, multiligamentous injuries, patients undergoing revision, or patients with contralateral ACL-deficient knees. In the femoral knot/press-fit technique, semitendinosus and gracilis tendons were prepared as 2 loops with knots. After passage through a bottleneck femoral tunnel, the grafts were fixed with a press-fit method (grafts' knots were stuck in the bottleneck of the femoral tunnel). A tie with Mersilene tape (Ethicon, Somerville, NJ) over a bone bridge for each tendon loop and an additional bioabsorbable interference screw were used for tibial fixation. The mean follow-up period was 38 months (range, 24 to 61 months). A significant improvement in knee function and symptoms was reported in most patients, as shown by improved Tegner scores, Lysholm knee scores, and International Knee Documentation Committee assessments (P < .01). The results of instrumented laxity testing, thigh muscle assessment, and radiologic assessment were clearly improved when compared with the preoperative status (P < .01). No statistically significant difference in outcomes could be observed between group A and group B (P = not significant). In this nonrandomized study, femoral knot/press-fit ACL reconstruction did not appear to provide increased anterior instability compared with that of conventional femoral interference screw ACL reconstruction. Favorable outcomes with regard to knee stability and patient

  3. Biological Effects of Orthodontic Tooth Movement Into the Grafted Alveolar Cleft.

    PubMed

    Sun, Jian; Zhang, Xiaoyue; Li, Renmei; Chen, Zhengxi; Huang, Yuanliang; Chen, Zhenqi

    2018-03-01

    Functional stimulus during orthodontic tooth movement into the grafted bone can lead to better alveolar bone grafting outcomes. The aim of this study was to analyze the biological effects of orthodontic tooth movement into the grafted alveolar cleft area with histologic staining, fluorescence staining, and real-time polymerase chain reaction (PCR). An animal model of orthodontic tooth movement into the grafted alveolar cleft area was established in 8-week-old Sprague-Dawley rats. The animals were divided into the experimental group and the control group. Four checkpoints were observed: before orthodontic stimuli, day 1 after orthodontic stimuli, day 3 after orthodontic stimuli, and day 5 after orthodontic stimuli. The cleft bone formation conditions, including the collagen fibers and the activities of the osteoclasts and osteoblasts, were evaluated by histologic staining. The expression of tartrate-resistant acid phosphatase (TRAP), receptor activator nuclear factor κB ligand, and Runt-related transcription factor 2 was detected by real-time PCR in both groups. Hematoxylin-eosin staining showed that the remodeling process of iliac autografts was completed when the orthodontic stress was applied, whereas the bone tissues first showed osteoclastogenesis and then osteogenesis. On the basis of TRAP staining, the osteoclasts increased to the maximal amount on day 3 and decreased thereafter. Evidence from tetracycline fluorescence staining indicated that no obvious changes in osteoblast activity were detected at the early stage; however, it gradually increased, especially in the region close to the root surface. According to real-time PCR, the expression of TRAP increased in both the early and middle stages, that of receptor activator nuclear factor κB ligand increased in the early stage, and that of Runt-related transcription factor 2 increased in the late stage. Moreover, the results showed significant differences between the experimental and control groups

  4. Effects of Biosynthetic Human Epidermal Growth Factor on Wound Healing

    DTIC Science & Technology

    1986-10-27

    regenerated or been replaced with autograft skin. The limiting factor in covering major third degree burns is the availability of autogenous skin grafts . Although...tho patient’s own skin. Since the only permant solution currently available is autografting, an agent that would accelerate healing of skin graft donor...biodegradation. Additional valuable information will be obtained when the limited clinical trial using EGF in Silvadene to treat skin graft donor sites begins

  5. Low-intensity pulsed ultrasound treatment improved the rate of autograft peripheral nerve regeneration in rat

    PubMed Central

    Jiang, Wenli; Wang, Yuexiang; Tang, Jie; Peng, Jiang; Wang, Yu; Guo, Quanyi; Guo, Zhiyuan; Li, Pan; Xiao, Bo; Zhang, Jinxing

    2016-01-01

    Low intensity pulsed ultrasound (LIPUS) has been widely used in clinic for the treatment of repairing pseudarthrosis, bone fractures and of healing in various soft tissues. Some reports indicated that LIPUS accelerated peripheral nerve regeneration including Schwann cells (SCs) and injured nerves. But little is known about its appropriate intensities on autograft nerves. This study was to investigate which intensity of LIPUS improved the regeneration of gold standard postsurgical nerves in experimental rat model. Sprague-Dawley rats were made into 10 mm right side sciatic nerve reversed autologous nerve transplantation and randomly treated with 250 mW/cm2, 500 mW/cm2 or 750 mW/cm2 LIPUS for 2–12 weeks after operation. Functional and pathological results showed that LIPUS of 250 mW/cm2 significantly induced faster rate of axonal regeneration. This suggested that autograft nerve regeneration was improved. PMID:27102358

  6. Controlled grafting of vinylic monomers on polyolefins: a robust mathematical modeling approach

    PubMed Central

    Saeb, Mohammad Reza; Rezaee, Babak; Shadman, Alireza; Formela, Krzysztof; Ahmadi, Zahed; Hemmati, Farkhondeh; Kermaniyan, Tayebeh Sadat; Mohammadi, Yousef

    2017-01-01

    Abstract Experimental and mathematical modeling analyses were used for controlling melt free-radical grafting of vinylic monomers on polyolefins and, thereby, reducing the disturbance of undesired cross-linking of polyolefins. Response surface, desirability function, and artificial intelligence methodologies were blended to modeling/optimization of grafting reaction in terms of vinylic monomer content, peroxide initiator concentration, and melt-processing time. An in-house code was developed based on artificial neural network that learns and mimics processing torque and grafting of glycidyl methacrylate (GMA) typical vinylic monomer on high-density polyethylene (HDPE). Application of response surface and desirability function enabled concurrent optimization of processing torque and GMA grafting on HDPE, through which we quantified for the first time competition between parallel reactions taking place during melt processing: (i) desirable grafting of GMA on HDPE; (ii) undesirable cross-linking of HDPE. The proposed robust mathematical modeling approach can precisely learn the behavior of grafting reaction of vinylic monomers on polyolefins and be placed into practice in finding exact operating condition needed for efficient grafting of reactive monomers on polyolefins. PMID:29491797

  7. Controlled grafting of vinylic monomers on polyolefins: a robust mathematical modeling approach.

    PubMed

    Saeb, Mohammad Reza; Rezaee, Babak; Shadman, Alireza; Formela, Krzysztof; Ahmadi, Zahed; Hemmati, Farkhondeh; Kermaniyan, Tayebeh Sadat; Mohammadi, Yousef

    2017-01-01

    Experimental and mathematical modeling analyses were used for controlling melt free-radical grafting of vinylic monomers on polyolefins and, thereby, reducing the disturbance of undesired cross-linking of polyolefins. Response surface, desirability function, and artificial intelligence methodologies were blended to modeling/optimization of grafting reaction in terms of vinylic monomer content, peroxide initiator concentration, and melt-processing time. An in-house code was developed based on artificial neural network that learns and mimics processing torque and grafting of glycidyl methacrylate (GMA) typical vinylic monomer on high-density polyethylene (HDPE). Application of response surface and desirability function enabled concurrent optimization of processing torque and GMA grafting on HDPE, through which we quantified for the first time competition between parallel reactions taking place during melt processing: (i) desirable grafting of GMA on HDPE; (ii) undesirable cross-linking of HDPE. The proposed robust mathematical modeling approach can precisely learn the behavior of grafting reaction of vinylic monomers on polyolefins and be placed into practice in finding exact operating condition needed for efficient grafting of reactive monomers on polyolefins.

  8. Bone regenerative medicine: classic options, novel strategies, and future directions

    PubMed Central

    2014-01-01

    This review analyzes the literature of bone grafts and introduces tissue engineering as a strategy in this field of orthopedic surgery. We evaluated articles concerning bone grafts; analyzed characteristics, advantages, and limitations of the grafts; and provided explanations about bone-tissue engineering technologies. Many bone grafting materials are available to enhance bone healing and regeneration, from bone autografts to graft substitutes; they can be used alone or in combination. Autografts are the gold standard for this purpose, since they provide osteogenic cells, osteoinductive growth factors, and an osteoconductive scaffold, all essential for new bone growth. Autografts carry the limitations of morbidity at the harvesting site and limited availability. Allografts and xenografts carry the risk of disease transmission and rejection. Tissue engineering is a new and developing option that had been introduced to reduce limitations of bone grafts and improve the healing processes of the bone fractures and defects. The combined use of scaffolds, healing promoting factors, together with gene therapy, and, more recently, three-dimensional printing of tissue-engineered constructs may open new insights in the near future. PMID:24628910

  9. Repair of articular cartilage defects in the knee with autologous iliac crest cartilage in a rabbit model.

    PubMed

    Jing, Lizhong; Zhang, Jiying; Leng, Huijie; Guo, Qinwei; Hu, Yuelin

    2015-04-01

    To demonstrate that iliac crest cartilage may be used to repair articular cartilage defects in the knees of rabbits. Full-thickness cartilage defects were created in the medial femoral condyle on both knees of 36 New Zealand white rabbits. The 72 defects were randomly assigned to be repaired with ipsilateral iliac crest cartilage (Group I), osteochondral tissues removed at defect creation (Group II), or no treatment (negative control, Group III). Animals were killed at 6, 12, and 24 weeks post-operatively. The repaired tissues were harvested for magnetic resonance imaging (MRI), histological studies (haematoxylin and eosin and immunohistochemical staining), and mechanical testing. At 6 weeks, the iliac crest cartilage graft was not yet well integrated with the surrounding articular cartilage, but at 12 weeks, the graft deep zone had partial ossification. By 24 weeks, the hyaline cartilage-like tissue was completely integrated with the surrounding articular cartilage. Osteochondral autografts showed more rapid healing than Group I at 6 weeks and complete healing at 12 weeks. Untreated defects were concave or partly filled with fibrous tissue throughout the study. MRI showed that Group I had slower integration with surrounding normal cartilage compared with Group II. The mechanical properties of Group I were significantly lower than those of Group II at 12 weeks, but this difference was not significant at 24 weeks. Iliac crest cartilage autografts were able to repair knee cartilage defects with hyaline cartilage and showed comparable results with osteochondral autografts in the rabbit model.

  10. Treatment of focal articular cartilage lesions of the knee with autogenous osteochondral graftsA 2- to 4-year follow-up study.

    PubMed

    Wang, Ching-Jen

    2002-04-01

    A retrospective study of 15 patients with 16 knees who underwent osteochondral autografts for focal full thickness articular cartilage defects of the knee with 2- to 4-year follow-up showed 80% good or excellent clinical results. There was no correlation of the clinical results with the underlying diagnoses, including osteonecrosis, osteochondritis dessicans and traumatic cartilage defect, or a size of the lesion smaller than 600 mm(2). However, cartilage lesions larger than 600 mm(2) were associated with increasing fibrous tissue formation and fissuring between the grafts and the host tissues and poor results. The improvement in symptoms appeared time-dependent, ranging from 6 to 16 weeks, suggesting that postoperative protection of the graft is warranted. There was no radiographic progression of degenerative changes of the knee on the medium-term follow-up. Therefore, an autogenous osteochondral graft is considered a good method in the treatment of knees with moderately sized articular cartilage defects.

  11. Ankle arthrodesis with bone graft after distal tibia resection for bone tumors.

    PubMed

    Campanacci, Domenico Andrea; Scoccianti, Guido; Beltrami, Giovanni; Mugnaini, Marco; Capanna, Rodolfo

    2008-10-01

    Treatment of distal tibial tumors is challenging due to the scarce soft tissue coverage of this area. Ankle arthrodesis has proven to be an effective treatment in primary and post-traumatic joint arthritis, but few papers have addressed the feasibility and techniques of ankle arthrodesis in tumor surgery after long bone resections. Resection of the distal tibia and reconstruction by ankle fusion using non-vascularized structural bone grafts was performed in 8 patients affected by malignant (5 patients) or aggressive benign (3 patients) tumors. Resection length of the tibia ranged from 5 to 21 cm. Bone defects were reconstructed with cortical structural autografts (from contralateral tibia) or allografts or both, plus autologous bone chips. Fixation was accomplished by antegrade nailing (6 cases) or plating (2~cases). All the arthrodesis successfully healed. At followup ranging from 23 to 113 months (average 53.5), all patients were alive. One local recurrence was observed with concomitant deep infection (a below-knee amputation was performed). Mean functional MSTS score of the seven available patients was 80.4% (range, 53 to 93). Resection of the distal tibia and arthrodesis of the ankle with non-vascularized structural bone grafts, combined with autologous bone chips, can be an effective procedure in bone tumor surgery with durable and satisfactory functional results. In shorter resections, autologous cortical structural grafts can be used; in longer resections, allograft structural bone grafts are needed.

  12. Reliability of a semi-automated 3D-CT measuring method for tunnel diameters after anterior cruciate ligament reconstruction: A comparison between soft-tissue single-bundle allograft vs. autograft.

    PubMed

    Robbrecht, Cedric; Claes, Steven; Cromheecke, Michiel; Mahieu, Peter; Kakavelakis, Kyriakos; Victor, Jan; Bellemans, Johan; Verdonk, Peter

    2014-10-01

    Post-operative widening of tibial and/or femoral bone tunnels is a common observation after ACL reconstruction, especially with soft-tissue grafts. There are no studies comparing tunnel widening in hamstring autografts versus tibialis anterior allografts. The goal of this study was to observe the difference in tunnel widening after the use of allograft vs. autograft for ACL reconstruction, by measuring it with a novel 3-D computed tomography based method. Thirty-five ACL-deficient subjects were included, underwent anatomic single-bundle ACL reconstruction and were evaluated at one year after surgery with the use of 3-D CT imaging. Three independent observers semi-automatically delineated femoral and tibial tunnel outlines, after which a best-fit cylinder was derived and the tunnel diameter was determined. Finally, intra- and inter-observer reliability of this novel measurement protocol was defined. In femoral tunnels, the intra-observer ICC was 0.973 (95% CI: 0.922-0.991) and the inter-observer ICC was 0.992 (95% CI: 0.982-0.996). In tibial tunnels, the intra-observer ICC was 0.955 (95% CI: 0.875-0.985). The combined inter-observer ICC was 0.970 (95% CI: 0.987-0.917). Tunnel widening was significantly higher in allografts compared to autografts, in the tibial tunnels (p=0.013) as well as in the femoral tunnels (p=0.007). To our knowledge, this novel, semi-automated 3D-computed tomography image processing method has shown to yield highly reproducible results for the measurement of bone tunnel diameter and area. This series showed a significantly higher amount of tunnel widening observed in the allograft group at one-year follow-up. Level II, Prospective comparative study. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Establishment of a rat and guinea pig aortic interposition graft model reveals model-specific patterns of intimal hyperplasia.

    PubMed

    Gregory, Elaine K; Vercammen, Janet M; Flynn, Megan E; Kibbe, Melina R

    2016-12-01

    Although the aortic interposition bypass model has been widely used to evaluate biomaterials for bypass grafting, there is no comprehensive description of the procedure or of the distribution of intimal hyperplasia that results. The objectives of this study were to (1) review and summarize approaches of aortic interposition grafting in animal models, (2) determine the pertinent anatomy for this procedure, (3) validate this model in the rat and guinea pig, and (4) compare the distribution of intimal hyperplasia that develops in each species. A literature search was performed in PubMed from 1980 to the present to analyze the use of anesthesia, anticoagulation, antiplatelet agents, graft material, suture, and anastomotic techniques. Using 10-week-old male Sprague-Dawley rats and Hartley guinea pigs, we established pertinent aortic anatomy, developed comparable models, and assessed complications for each model. At 30 days, the graft and associated aorta were explanted, intimal formation was assessed morphometrically, and cellularity was assessed via nuclear counting. We reviewed 30 articles and summarized the pertinent procedural findings. Upon establishing both animal models, key anatomic differences between the species that affect this model were noted. Guinea pigs have a much larger cecum, increased retroperitoneal fat, and lack the iliolumbar vessels compared with the rat. Surgical outcomes for the rat model included a 53% technical success rate and a 32% technical error rate. Surgical outcomes for the guinea pig model included a 69% technical success rate and a 31% technical error rate. These two species demonstrated unique distribution of intimal hyperplasia at 30 days. Intimal hyperplasia in the rat model was greatest at two areas, the proximal graft (5400 μm 2 ; P < .001) and distal graft (2800 μm 2 ; P < .04), whereas the guinea pig model developed similar intimal hyperplasia throughout the graft (4500-5100 μm 2 ; P < .01). In this report, we summarize

  14. A Novel Porcine Model for Future Studies of Cell-enriched Fat Grafting

    PubMed Central

    Sørensen, Celine L.; Vester-Glowinski, Peter V.; Herly, Mikkel; Kurbegovic, Sorel; Ørholt, Mathias; Svalgaard, Jesper D.; Kølle, Stig-Frederik T.; Kristensen, Annemarie T.; Talman, Maj-Lis M.; Drzewiecki, Krzysztof T.; Fischer-Nielsen, Anne

    2018-01-01

    Background: Cell-enriched fat grafting has shown promising results for improving graft survival, although many questions remain unanswered. A large animal model is crucial for bridging the gap between rodent studies and human trials. We present a step-by-step approach in using the Göttingen minipig as a model for future studies of cell-enriched large volume fat grafting. Methods: Fat grafting was performed as bolus injections and structural fat grafting. Graft retention was assessed by magnetic resonance imaging after 120 days. The stromal vascular fraction (SVF) was isolated from excised fat and liposuctioned fat from different anatomical sites and analyzed. Porcine adipose-derived stem/stromal cells (ASCs) were cultured in different growth supplements, and population doubling time, maximum cell yield, expression of surface markers, and differentiation potential were investigated. Results: Structural fat grafting in the breast and subcutaneous bolus grafting in the abdomen revealed average graft retention of 53.55% and 15.28%, respectively, which are similar to human reports. Liposuction yielded fewer SVF cells than fat excision, and abdominal fat had the most SVF cells/g fat with SVF yields similar to humans. Additionally, we demonstrated that porcine ASCs can be readily isolated and expanded in culture in allogeneic porcine platelet lysate and fetal bovine serum and that the use of 10% porcine platelet lysate or 20% fetal bovine serum resulted in population doubling time, maximum cell yield, surface marker profile, and trilineage differentiation that were comparable with humans. Conclusions: The Göttingen minipig is a feasible and cost-effective, large animal model for future translational studies of cell-enriched fat grafting. PMID:29876178

  15. Solitary haemangioma of the shaft of long bones: resection and reconstruction with autologous bone graft.

    PubMed

    Li, Zhaoxu; Tang, Jicun; Ye, Zhaoming

    2013-04-01

    Bone haemangiomas are uncommon lesions, occurring in the skull or spine. A solitary haemangioma in the diaphysis of a long bone is rare. We retrospectively investigated six patients who presented with a solitary haemangioma in a long bone diaphysis. After segmental bone resection, the bone defect was replaced by a bone autograft. Patients were reviewed clinically and with radiographs. The mean follow-up was 6 years (range : 1-20 years). At the time of latest follow-up, no patient had a recurrence. Postoperative complications were one wound necrosis and one superficial wound infection. Union of the gap filling graft with the host bone was achieved in all patients at an average of 4 months (range: 3-8 months). The average Musculoskeletal Tumor Society functional score was 77% (range: 53%-90%) of normal at 6 months postoperatively, and 97% (range: 95%-99%) at the last follow-up evaluation. Segmental resection for solitary haemangioma and reconstruction with autologous bone graft can be considered as a suitable treatment option.

  16. Hamstring Graft Preparation Using a Modified Rolling Hitch Technique

    PubMed Central

    Hong, Chih-Kai; Chang, Chih-Hsun; Chiang, Chen-Hao; Jou, I-Ming; Su, Wei-Ren

    2014-01-01

    Anterior cruciate ligament reconstruction using double-looped hamstring autograft is a common procedure in orthopaedic practice. However, during placement of the running, locking stitches at each end of the harvested tendons, the surgeon may face several potential obstacles, including the risk of damaging the tendon, predisposing the surgeon to needle-stick injury, and extended time consumption. We report a modified rolling hitch technique for hamstring graft preparation that is quick, cost-saving, and needleless as an alternative method. The original rolling hitch technique uses a traditional knot that attaches a rope to an object; the modified rolling hitch technique was created by adding 1 more turn before finishing with a half-hitch, which may prevent suture slippage off the tendon, thus providing sufficient fixation of the suture-tendon construct. PMID:25126495

  17. Amniotic membrane transplantation with conjunctival autograft for recurrent pterygium.

    PubMed

    Shimazaki, Jun; Kosaka, Koichi; Shimmura, Shigeto; Tsubota, Kazuo

    2003-01-01

    To study the effect of amniotic membrane transplantation (AMT) combined with either limbal autograft transplantation (LAT) or conjunctival autograft transplantation (CAT) in recurrent pterygium. Retrospective, noncomparative, interventional case series. Twenty-seven eyes of 27 patients with recurrent pterygium. The mean number of prior surgeries was 3.1 (range, 1-10). Fifteen eyes each had restriction of ocular movement and symblepharon before surgery. Patients were treated by AMT with either LAT (n = 15) or CAT (n = 12). Recurrence of pterygium, improvement in ocular movement, and symblepharon formation. Twenty-three (85.2%) of 27 eyes showed no recurrence with a mean observation period of 67.0 weeks. Fourteen eyes (93.3%) each showed improvement in ocular movement restriction and symblepharon after AMT. In four eyes that developed recurrence, three had LAT and one had CAT combined with AMT, suggesting that there was no difference in surgical outcome between LAT and CAT. AMT with CAT is a safe and effective method for recurrent pterygium, especially that associated with ocular movement restriction and symblepharon. Considering the potential adverse effects associated with limbal excision, AMT plus CAT may be preferred over AMT plus LAT.

  18. Efficacy of different bone volume expanders for augmenting lumbar fusions.

    PubMed

    Epstein, Nancy E

    2008-01-01

    A wide variety of bone volume expanders are being used in performing posterolateral lumbar noninstrumented and instrumented lumbar fusions. This article presents a review of their efficacy based on fusion rates, complications, and outcomes. Lumbar noninstrumented and instrumented fusions frequently use laminar autografts and different bone graft expanders. This review presents the utility of multiple forms/ratios of DBMs containing allografts. It also discusses the efficacy of artificial bone graft substitutes, including HA and B-TCP. Dynamic x-ray and/or CT examinations were used to document fusion in most series. Outcomes were variously assessed using Odom's criteria or different outcome questionnaires (Oswestry Questionnaire, SF-36, Dallas Pain Questionnaire, and/or Low Back Pain Rating Scale). Performing noninstrumented and instrumented lumbar posterolateral fusions resulted in comparable fusion rates in many series. Similar outcomes were also documented based on Odom's criteria or the multiple patient-based questionnaires. However, in some studies, the addition of spinal instrumentation increased the reoperation rate, operative time, blood loss, and cost. Various forms of DBMs, applied in different ratios to autografts, effectively supplemented spinal fusions in animal models and patient series. beta-Tricalcium phosphate, which is used to augment autograft fusions addressing idiopathic scoliosis or lumbar disease, also proved to be effective. Different types of bone volume expanders, including various forms of allograft-based DBMs, and artificial bone graft substitutes (HA and B-TCP) effectively promote posterolateral lumbar noninstrumented and instrumented fusions when added to autografts.

  19. Is height the best predictor for adequacy of semitendinosus-alone anterior cruciate ligament reconstruction? A study of hamstring graft dimensions and anthropometric measurements.

    PubMed

    Sundararajan, S R; Rajagopalakrishnan, Ramakanth; Rajasekaran, S

    2016-05-01

    To predict adequacy of semitendinosus (ST) graft dimension for ACLR from anthropometric measures. Single tendon harvest for autograft hamstring ACLR could be beneficial to limit donor site morbidity; however, concerns for reconstruction failure based upon inadequate graft size may limit this surgical technique. To predict adequacy, prospectively, 108 patients who underwent ACLR by hamstring graft (STG graft) were enrolled for the study. Mean age was 33.028 years ± 9.539 SD (14-59) with 88 males and 20 females. Anthropometric measurements (height, weight, BMI, thigh and total limb length) and intraoperative data (graft dimensions and bone tunnel measurements) were collected for analysis. Semitendinosus graft can be used as 3-strand (ST3) or 4-strand (ST4) graft. Adequacy criteria for ST3 and ST4 graft dimensions were determined from data analysis. SPSS (v.17) Pearson's correlation coefficient and ROC curves were used for statistical analyses. A total of 74 out of 108 patients (68.52 %) had adequate graft dimensions for ST3 reconstruction. Height equal or greater than 158 cm was predictive of adequate graft for ST3 reconstruction. Only 23 patients (21.3 %) had adequate graft dimensions for ST4 reconstruction. Height equal or greater than 170 cm was predictive of adequate graft for ST4 reconstruction. Height variable had the highest ROC curve area of 0.840 and 0.910 for both ST3 graft and ST4 graft, respectively. Hence, height was used as best predictor to determine adequacy of the graft. Height can be predictive of adequate graft for single tendon ACL reconstruction.

  20. A Rabbit Model for Testing Helper-Dependent Adenovirus-Mediated Gene Therapy for Vein Graft Atherosclerosis.

    PubMed

    Bi, Lianxiang; Wacker, Bradley K; Bueren, Emma; Ham, Ervin; Dronadula, Nagadhara; Dichek, David A

    2017-12-15

    Coronary artery bypass vein grafts are a mainstay of therapy for human atherosclerosis. Unfortunately, the long-term patency of vein grafts is limited by accelerated atherosclerosis. Gene therapy, directed at the vein graft wall, is a promising approach for preventing vein graft atherosclerosis. Because helper-dependent adenovirus (HDAd) efficiently transduces grafted veins and confers long-term transgene expression, HDAd is an excellent candidate for delivery of vein graft-targeted gene therapy. We developed a model of vein graft atherosclerosis in fat-fed rabbits and demonstrated long-term (≥20 weeks) persistence of HDAd genomes after graft transduction. This model enables quantitation of vein graft hemodynamics, wall structure, lipid accumulation, cellularity, vector persistence, and inflammatory markers on a single graft. Time-course experiments identified 12 weeks after transduction as an optimal time to measure efficacy of gene therapy on the critical variables of lipid and macrophage accumulation. We also used chow-fed rabbits to test whether HDAd infusion in vein grafts promotes intimal growth and inflammation. HDAd did not increase intimal growth, but had moderate-yet significant-pro-inflammatory effects. The vein graft atherosclerosis model will be useful for testing HDAd-mediated gene therapy; however, pro-inflammatory effects of HdAd remain a concern in developing HDAd as a therapy for vein graft disease.

  1. Evaluation of Polycaprolactone Scaffold with Basic Fibroblast Growth Factor and Fibroblasts in an Athymic Rat Model for Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Kabir, Nima; Arshi, Armin; Nazemi, Azadeh; Wu, Ben; Petrigliano, Frank A.; McAllister, David R.

    2015-01-01

    Anterior cruciate ligament (ACL) rupture is a common ligamentous injury often necessitating surgery. Current surgical treatment options include ligament reconstruction with autograft or allograft, which have their inherent limitations. Thus, there is interest in a tissue-engineered substitute for use in ACL regeneration. However, there have been relatively few in vivo studies to date. In this study, an athymic rat model of ACL reconstruction was used to evaluate electrospun polycaprolactone (PCL) grafts, with and without the addition of basic fibroblast growth factor (bFGF) and human foreskin fibroblasts. We examined the regenerative potential of tissue-engineered ACL grafts using histology, immunohistochemistry, and mechanical testing up to 16 weeks postoperatively. Histology showed infiltration of the grafts with cells, and immunohistochemistry demonstrated aligned collagen deposition with minimal inflammatory reaction. Mechanical testing of the grafts demonstrated significantly higher mechanical properties than immediately postimplantation. Acellular grafts loaded with bFGF achieved 58.8% of the stiffness and 40.7% of the peak load of healthy native ACL. Grafts without bFGF achieved 31.3% of the stiffness and 28.2% of the peak load of healthy native ACL. In this in vivo rodent model study for ACL reconstruction, the histological and mechanical evaluation demonstrated excellent healing and regenerative potential of our electrospun PCL ligament graft. PMID:25744933

  2. Risk prediction models for graft failure in kidney transplantation: a systematic review.

    PubMed

    Kaboré, Rémi; Haller, Maria C; Harambat, Jérôme; Heinze, Georg; Leffondré, Karen

    2017-04-01

    Risk prediction models are useful for identifying kidney recipients at high risk of graft failure, thus optimizing clinical care. Our objective was to systematically review the models that have been recently developed and validated to predict graft failure in kidney transplantation recipients. We used PubMed and Scopus to search for English, German and French language articles published in 2005-15. We selected studies that developed and validated a new risk prediction model for graft failure after kidney transplantation, or validated an existing model with or without updating the model. Data on recipient characteristics and predictors, as well as modelling and validation methods were extracted. In total, 39 articles met the inclusion criteria. Of these, 34 developed and validated a new risk prediction model and 5 validated an existing one with or without updating the model. The most frequently predicted outcome was graft failure, defined as dialysis, re-transplantation or death with functioning graft. Most studies used the Cox model. There was substantial variability in predictors used. In total, 25 studies used predictors measured at transplantation only, and 14 studies used predictors also measured after transplantation. Discrimination performance was reported in 87% of studies, while calibration was reported in 56%. Performance indicators were estimated using both internal and external validation in 13 studies, and using external validation only in 6 studies. Several prediction models for kidney graft failure in adults have been published. Our study highlights the need to better account for competing risks when applicable in such studies, and to adequately account for post-transplant measures of predictors in studies aiming at improving monitoring of kidney transplant recipients. © The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  3. Free Bone Plug Quadriceps Tendon Harvest and Suspensory Button Attachment for Anterior Cruciate Ligament Reconstruction.

    PubMed

    Todor, Adrian; Caterev, Sergiu; Nistor, Dan Viorel; Khallouki, Youssef

    2016-06-01

    The most commonly used autografts for anterior cruciate ligament reconstruction are the bone-patellar tendon-bone and hamstring tendons. Each has its advantages and limitations. The bone-patellar tendon-bone autograft can lead to more donor-site morbidity, and the hamstring autograft can be unpredictable in size. The quadriceps tendon, with or without a bone block, has been described as an alternative graft source and has been used especially in revision cases, but in recent years, it has attracted attention even for primary cases. We report a technique for harvesting a free bone quadriceps tendon graft and attaching an extracortical button for femoral fixation for anterior cruciate ligament reconstruction.

  4. Real-Time Demonstration of Split Skin Graft Inosculation and Integra Dermal Matrix Neovascularization Using Confocal Laser Scanning Microscopy

    PubMed Central

    Greenwood, John; Amjadi, Mahyar; Dearman, Bronwyn; Mackie, Ian

    2009-01-01

    Objectives: During the first 48 hours after placement, an autograft “drinks” nutrients and dissolved oxygen from fluid exuding from the underlying recipient bed (“plasmatic imbibition”). The theory of inosculation (that skin grafts subsequently obtain nourishment via blood vessel “anastomosis” between new vessels invading from the wound bed and existing graft vessels) was hotly debated from the late 19th to mid-20th century. This study aimed to noninvasively observe blood flow in split skin grafts and Integra™ dermal regeneration matrix to provide further proof of inosculation and to contrast the structure of vascularization in both materials, reflecting mechanism. Methods: Observations were made both clinically and using confocal microscopy on normal skin, split skin graft, and Integra™. The VivaScope™ allows noninvasive, real-time, in vivo images of tissue to be obtained. Results: Observations of blood flow and tissue architecture in autologous skin graft and Integra™ suggest that 2 very different processes are occurring in the establishment of circulation in each case. Inosculation provides rapid circulatory return to skin grafts whereas slower neovascularization creates an unusual initial Integra™ circulation. Conclusions: The advent of confocal laser microscopy like the VivaScope 1500™, together with “virtual” journals such as ePlasty, enables us to provide exciting images and distribute them widely to a “reading” audience. The development of the early Integra™ vasculature by neovascularization results in a large-vessel, high-volume, rapid flow circulation contrasting markedly from the inosculatory process in skin grafts and the capillary circulation in normal skin and merits further (planned) investigation. PMID:19787028

  5. Early experience and results of bone graft enriched with autologous platelet gel for recalcitrant nonunions of lower extremity.

    PubMed

    Chiang, Chao-Ching; Su, Chen-Yao; Huang, Ching-Kuei; Chen, Wei-Ming; Chen, Tain-Hsiung; Tzeng, Yun-Hsuan

    2007-09-01

    Refractory nonunions of the tibia or femur are physically and mentally devastating conditions for the patients, and the treatment is challenging for orthopedic surgeons. The goal of this study was to assess the feasibility and outcome of surgical treatment in recalcitrant nonunions of a lower extremity with bone graft enriched with autologous platelet gel (APG). Twelve patients with four femoral and eight tibial atrophic nonunions after multiple prior procedures were included. All of them were treated with the bone grafting procedures with autograft complex enriched with APG. They were evaluated with radiographs, bone mineral density for bony healing process, and the Short-Form 36 Health Survey for functional outcome. Of the 12 patients, 11 healed at an average of 19.7 weeks after the first attempt and 1 healed after the second attempt at 21 weeks. The bone mineral density continued to increase steadily from early healing to the remodeling phase. Functional status was greatly improved at an average follow-up of 32.4 months. The results of this preliminary study implied the possible potential of bone graft enriched with APG in the treatment of recalcitrant nonunions of the lower extremity. More research is necessary to clarify its role in augmentation of bone graft to enhance healing of nonunion.

  6. Stem Cells in Spinal Fusion

    PubMed Central

    Haudenschild, Dominik R.; Wegner, Adam M.; Klineberg, Eric O.

    2017-01-01

    Study Design: Review of literature. Objectives: This review of literature investigates the application of mesenchymal stem cells (MSCs) in spinal fusion, highlights potential uses in the development of bone grafts, and discusses limitations based on both preclinical and clinical models. Methods: A review of literature was conducted looking at current studies using stem cells for augmentation of spinal fusion in both animal and human models. Results: Eleven preclinical studies were found that used various animal models. Average fusion rates across studies were 59.8% for autograft and 73.7% for stem cell–based grafts. Outcomes included manual palpation and stressing of the fusion, radiography, micro–computed tomography (μCT), and histological analysis. Fifteen clinical studies, 7 prospective and 8 retrospective, were found. Fusion rates ranged from 60% to 100%, averaging 87.1% in experimental groups and 87.2% in autograft control groups. Conclusions: It appears that there is minimal clinical difference between commercially available stem cells and bone marrow aspirates indicating that MSCs may be a good choice in a patient with poor marrow quality. Overcoming morbidity and limitations of autograft for spinal fusion, remains a significant problem for spinal surgeons and further studies are needed to determine the efficacy of stem cells in augmenting spinal fusion. PMID:29238646

  7. Co-delivery of a laminin-111 supplemented hyaluronic acid based hydrogel with minced muscle graft in the treatment of volumetric muscle loss injury

    PubMed Central

    Goldman, Stephen M.; Henderson, Beth E. P.; Walters, Thomas J.

    2018-01-01

    Minced muscle autografting mediates de novo myofiber regeneration and promotes partial recovery of neuromuscular strength after volumetric muscle loss injury (VML). A major limitation of this approach is the availability of sufficient donor tissue for the treatment of relatively large VMLs without inducing donor site morbidity. This study evaluated a laminin-111 supplemented hyaluronic acid based hydrogel (HA+LMN) as a putative myoconductive scaffolding to be co-delivered with minced muscle grafts. In a rat tibialis anterior muscle VML model, delivery of a reduced dose of minced muscle graft (50% of VML defect) within HA+LMN resulted in a 42% improvement of peak tetanic torque production over unrepaired VML affected limbs. However, the improvement in strength was not improved compared to a 50% minced graft-only control group. Moreover, histological analysis revealed that the improvement in in vivo functional capacity mediated by minced grafts in HA+LMN was not accompanied by a particularly robust graft mediated regenerative response as determined through donor cell tracking of the GFP+ grafting material. Characterization of the spatial distribution and density of macrophage and satellite cell populations indicated that the combination therapy damps the heightened macrophage response while re-establishing satellite content 14 days after VML to a level consistent with an endogenously healing ischemia-reperfusion induced muscle injury. Moreover, regional analysis revealed that the combination therapy increased satellite cell density mostly in the remaining musculature, as opposed to the defect area. Based on the results, the following salient conclusions were drawn: 1) functional recovery mediated by the combination therapy is likely due to a superposition of de novo muscle fiber regeneration and augmented repair of muscle fibers within the remaining musculature, and 2) The capacity for VML therapies to augment regeneration and repair within the remaining musculature

  8. Bone Grafting the Glenoid Versus Use of Augmented Glenoid Baseplates with Reverse Shoulder Arthroplasty.

    PubMed

    Jones, Richard B; Wright, Thomas W; Roche, Christopher P

    2015-12-01

    Large glenoid defects are a difficult reconstructive problem for surgeons performing reverse shoulder arthroplasty (rTSA). Options to address glenoid defects include eccentric reaming, bone grafting, and augmented glenoid baseplates. Augmented glenoid baseplates may provide a simpler, cost-effective, bone-preserving option compared to other techniques. No studies report the use of augmented baseplates to correct glenoid deformity in rTSA relative to the use of glenoid bone graft. We retrospectively reviewed 80 patients that received a primary rTSA and received either a structural bone graft or an augmented glenoid baseplate to address a significant glenoid defect. There were 39 patients in the augmented baseplate cohort and 41 patients in the bone graft cohort. The augmented baseplate cohort contained 24 8° posterior augment implants and 15 10° superior augment baseplates. The bone graft cohort consisted of 36 autograft humeral heads and 5 allograft femoral heads. The average follow-up for rTSA patients with an augmented baseplate was 28.3 ± 5.7 months, and the average follow-up for rTSA patients with glenoid bone graft was 34.1 ± 15.0 months. Each patient was scored preoperatively and at latest follow-up using the SST, UCLA, ASES, Constant, and SPADI metrics. Range of motion data was obtained as well. All patients demonstrated significant improvements in pain, ROM, and functional scores following treatment with rTSA using either augmented baseplates or glenoid bone graft to correct glenoid defects. The database contained no complications for the augmented glenoid baseplate cohort, and six complications (14.6%) for the glenoid bone graft cohort (including two glenoid loosenings and graft failures). Additionally, the augmented baseplate cohort showed a lower scapular notching rate of 10% as compared to the bone graft cohort which had a notching rate of 18.5%. The results of this study suggest that either augmented glenoid baseplates or glenoid bone graft can be

  9. A comparative clinical study of the efficacy of subepithelial connective tissue graft and acellular dermal matrix graft in root coverage: 6-month follow-up observation

    PubMed Central

    Thomas, Libby John; Emmadi, Pamela; Thyagarajan, Ramakrishnan; Namasivayam, Ambalavanan

    2013-01-01

    Aims: The purpose of this study was to compare the clinical efficacy of subepithelial connective tissue graft and acellular dermal matrix graft associated with coronally repositioned flap in the treatment of Miller's class I and II gingival recession, 6 months postoperatively. Settings and Design: Ten patients with bilateral Miller's class I or class II gingival recession were randomly divided into two groups using a split-mouth study design. Materials and Methods: Group I (10 sites) was treated with subepithelial connective tissue graft along with coronally repositioned flap and Group II (10 sites) treated with acellular dermal matrix graft along with coronally repositioned flap. Clinical parameters like recession height and width, probing pocket depth, clinical attachment level, and width of keratinized gingiva were evaluated at baseline, 90th day, and 180th day for both groups. The percentage of root coverage was calculated based on the comparison of the recession height from 0 to 180th day in both Groups I and II. Statistical Analysis Used: Intragroup parameters at different time points were measured using the Wilcoxon signed rank test and Mann–Whitney U test was employed to analyze the differences between test and control groups. Results: There was no statistically significant difference in recession height and width, gain in CAL, and increase in the width of keratinized gingiva between the two groups on the 180th day. Both procedures showed clinically and statistically significant root coverage (Group I 96%, Group II 89.1%) on the 180th day. Conclusions: The results indicate that coverage of denuded root with both subepithelial connective tissue autograft and acellular dermal matrix allograft are very predictable procedures, which were stable for 6 months postoperatively. PMID:24174728

  10. [The effect of curiozin gel and adhesive plaster application on the healing and blood flow dynamics in skin autografts from various areas of body in rats].

    PubMed

    Zadorozhnyĭ, A A; Shtrygol', S Iu; Kataev, S I

    2004-01-01

    The stimulating effect of curiozin gel and plaster application on the engraftment of skin autografts from various areas of body was studied in rats. Curiozin gel in a single dose of 75 mg was used for the daily treatment of autografts over the entire postoperation period of time. The adhesive plaster was applied onto skin autografts for 5 days after skin transplantation. The skin autografts in the test group exhibited normalized volume blood flow dynamics, reduced duration of the inflammatory reaction, and improved the quality of engraftment as compared to the untreated control group. The best healing and blood-flow-normalizing effect was achieved by combined application of curiozin gel and adhesive plaster.

  11. Volume changes of autogenous bone after sinus lifting and grafting procedures: a 6-year computerized tomographic follow-up.

    PubMed

    Sbordone, Carolina; Toti, Paolo; Guidetti, Franco; Califano, Luigi; Bufo, Pantaleo; Sbordone, Ludovico

    2013-04-01

    To evaluate long-term bone remodelling of autografts over time (annually, for 6 years), comparing the block and particulate bone procedures for sinus floor elevation, as well as to evaluate the survival of positioned dental implants. Twenty-three sinus lift procedures with autogenous bone were performed: seven sinus lift procedures using particulate graft and 10 with block autogenous bone were performed in 17 patients. Employing a software program, pre- and post-surgical computerized tomography (CT) scans were used to compare the volume (V) and density (D) of inlay grafts over time (up to 6 years), and to determine the percentage of remaining bone (%R). All variable (V, D and %R) measurements were then compared statistically. At the 6-year survey for block form, a resorption of 21.5% was seen, whereas for particulate grafts there was a resorption of 39.2%. Both groups exhibited bone remodelling between the first and second follow-up which was significant regarding volume for the block form and regarding density for the particulate group. During the initial period of healing, the cortico-cancellous block bone grafted into the maxillary sinus underwent a negative remodelling of the volume, which is most probably due to graft cortex resorption, coupled with, primarily, an increase in density in the spongious area; for the particulate grafts, significant augmentations in density were obtained. The lack of significant differences among volumes was due to the wide degree of dispersion of the data. The rough data presented in this paper seem to support the use of a bone-block grafting procedure in maxillary sinus augmentation. Copyright © 2012 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  12. Proximal hamstring reconstruction using semitendinosus and gracilis autograft: a novel technique.

    PubMed

    Muellner, Thomas; Kumar, Sandeep; Singla, Amit

    2017-01-01

    The complete proximal hamstring avulsion is relatively uncommon injury and predominantly occurs in young athletes but causes significant functional impairment. In chronic cases, the muscle mass is so much retracted that primary repair is not possible. A surgical technique for reconstruction of chronic proximal hamstring avulsion using contralateral semitendinosus and gracilis autograft is described in this case report. V.

  13. Lyophilized keratinocyte cell lysates contain multiple mitogenic activities and stimulate closure of meshed skin autograft-covered burn wounds with efficiency similar to that of fresh allogeneic keratinocyte cultures.

    PubMed

    Duinslaeger, L; Verbeken, G; Reper, P; Delaey, B; Vanhalle, S; Vanderkelen, A

    1996-07-01

    For several years, grafting with allogeneic keratinocyte cultures has been used successfully as a wound-healing therapy both by us and by many other groups. Since their postgrafting survival time is limited, the effect of these cultures is generally explained by the production of wound repair-stimulating factors that promote proliferation and migration of resident cells. In this study we show that lysates of cultured keratinocytes contain mitogenic activity for keratinocytes, endothelial cells, and fibroblasts. In addition, the lysates inhibit the contraction of collagen gels by human skin fibroblasts. On the basis of these observations and of in vivo data obtained by ourselves and others, we have evaluated the effect of total keratinocyte lysates on the healing of meshed skin autograft-covered burn wounds. Twenty burn wounds were tangentially excised and autografted with one to three meshed conventional skin transplants. An area treated with a gel containing lysated keratinocyte cultures was compared with an area treated with placebo-gel in terms of epithelialization on day 5. In six patients an additional fresh keratinocyte alloculture was applied as a positive control. Results indicate that the newly formed epithelium (difference between percentage of epithelialization on day 5 and on day 0) was 31.1 percent in the treated area compared with 16.5 percent in the placebo area. This result is comparable with the value obtained by treatment with fresh keratinocyte allocultures, namely, 33.8 percent. These figures show a twofold stimulation of epithelialization.

  14. Texture analysis of computed tomographic images in osteoporotic patients with sinus lift bone graft reconstruction.

    PubMed

    Marchand-Libouban, Hélène; Guillaume, Bernard; Bellaiche, Norbert; Chappard, Daniel

    2013-05-01

    Bone implants are now widely used to replace missing teeth. Bone grafting (sinus lift) is a very useful way to increase the bone volume of the maxilla in patients with bone atrophy. There is a 6- to 9-month delay for the receiver grafted site to heal before the implants can be placed. Computed tomography is a useful method to measure the amount of remaining bone before implantation and to evaluate the quality of the receiver bone at the end of the healing period. Texture analysis is a non-invasive method useful to characterize bone microarchitecture on X-ray images. Ten patients in which a sinus lift surgery was necessary before implantation were analyzed in the present study. All had a bone reconstruction with a combination of a biomaterial (beta tricalcium phosphate) and autograft bone harvested at the chin. Computed tomographic images were obtained before grafting (t0), at mid-interval (t1, 4.2 ± 0.7 months) and before implant placement (t2, 9.2 ± 0.6 months). Texture analysis was done with the run-length method. A significant increase of texture parameters at t1 reflected a gain of homogeneity due to the graft and the beginning of bone remodeling. At t2, some parameters remained high and corresponded to the persistence of bone trabeculae while the resorption of biomaterials was identified by other parameters which tended to return to pregraft values. Texture analysis identified changes during the healing of the receiver site. The method is known to correlate with microarchitectural changes in bone and could be a useful approach to characterized osseointegrated grafts.

  15. Relationship between flow and incidence of thrombosis in polytetrafluoroethylene vascular grafts in free microvascular flaps in lambs.

    PubMed

    Paloma, V; Lasso, J M; Bazán, A; Serra, J M

    1999-09-01

    We have done an experimental study in lambs in which we investigated the influence of flow rate on free microvascular flaps using polytetrafluoroethylene (PTFE) vascular grafts. We set up five surgical groups in which blood flow was progressively increased through the PTFE vascular graft. In group I (venous autograft) we observed just one vascular thrombosis which was located at the site of the anastomosis. In group II (PTFE 3 x 10 mm) all the microvascular flaps became necrosed after the third postoperative day. In group III (PTFE 3 x 10 mm) necrosis also developed in all cases, but the anastomoses remained permeable no longer than eight days. In group IV (3 x 15 mm) the permeability in the microvascular free flaps was about 40% after 21 days, and in group V (3 x 10 mm) it reached 70%. To match graft flow rates with flap survival we did a regression analysis of flow rates for groups II, III, and V and the corresponding survival periods for the flaps. There was a clear and highly significant relationship (r = 0.717, p = 0.0001). In conclusion, it is necessary to maintain blood flow through the prosthesis at a rate higher than the thrombogenic threshold. When the flow rate in the vessels through the PTFE grafts was higher, the viability of the flaps was better. The ideal surgical technique should always be based on an arteriovenous fistula distal to the PTFE vascular graft. It is necessary to maintain blood flow through a prosthesis at a rate higher than the thrombogenic threshold.

  16. Acetabular Reconstruction With Femoral Head Autograft After Intraarticular Resection of Periacetabular Tumors is Durable at Short-term Followup.

    PubMed

    Tang, Xiaodong; Guo, Wei; Yang, Rongli; Yan, Taiqiang; Tang, Shun; Li, Dasen

    2017-12-01

    Pelvic reconstruction after periacetabular tumor resection is technically difficult and characterized by a high complication rate. Although endoprosthetic replacement can result in immediate postoperative functional recovery, biologic reconstructions with autograft may provide an enhanced prognosis in patients with long-term survival; however, little has been published regarding this approach. We therefore wished to evaluate whether whole-bulk femoral head autograft that is not contaminated by tumor can be used to reconstruct segmental bone defects after intraarticular resection of periacetabular tumors. In a pilot study, we evaluated (1) local tumor control, (2) complications, and (3) postoperative function as measured by the Musculoskeletal Tumor Society score. Between 2009 and 2015, we treated 13 patients with periacetabular malignant or aggressive benign tumors with en bloc resection, bulk femoral head autograft, and cemented THA (with or without a titanium acetabular reconstruction cup), and all were included for analysis here. During that time, the general indications for this approach were (1) patients anticipated to have a good oncologic prognosis and adequate surgical margins to allow this approach, (2) patients whose pelvic bone defects did not exceed two types (Types I + II or Types II + III as defined by Enneking and Dunham), and (3) patients whose medical insurance would not cover what otherwise might have been a pelvic tumor prosthesis. During this period, another 91 patients were treated with pelvic prosthetic replacement, which was our preferred approach. Median followup in this study was 36 months (range, 24-99 months among surviving patients; one patient died 8 months after surgery); no patients were lost to followup. Bone defects were Types II + III in five patients, and Types I + II in eight. After intraarticular resection, ipsilateral femoral head autograft combined with THA was used to reconstruct the segmental bone defect of the acetabulum

  17. Graft position in arthroscopic anterior cruciate ligament reconstruction: anteromedial versus transtibial technique.

    PubMed

    Guler, Olcay; Mahırogulları, Mahir; Mutlu, Serhat; Cercı, Mehmet H; Seker, Ali; Cakmak, Selami

    2016-11-01

    When treating anterior cruciate ligament (ACL) injuries, the position of the ACL graft plays a key role in regaining postoperative knee function and physiologic kinematics. In this study, we aimed to compare graft angle, graft position in tibial tunnel, and tibial and femoral tunnel positions in patients operated with anteromedial (AM) and transtibial (TT) methods to those of contralateral healthy knees. Forty-eight patients who underwent arthroscopic ACL reconstruction with ipsilateral hamstring tendon autograft were included. Of these, 23 and 25 were treated by AM and TT techniques, respectively. MRI was performed at 18.4 and 19.7 months postoperatively in AM and TT groups. Graft angles, graft positions in the tibial tunnel and alignment of tibial and femoral tunnels were noted and compared in these two groups. The sagittal graft insertion tibia midpoint distance (SGON) has been used for evaluation of graft position in tunnel. Sagittal ACL graft angles in operated and healthy knees of AM patients were 57.78° and 46.80° (p < 0.01). With respect to TT patients, ACL graft angle was 58.87° and 70.04° on sagittal and frontal planes in operated knees versus 47.38° and 61.82° in healthy knees (p < 0.001). ACL graft angle was significantly different between the groups on both sagittal and frontal planes (p < 0.001). Sagittal graft insertion tibia midpoint distance ratio was 0.51 and 0.48 % in the operated and healthy knees of AM group (p < 0.001) and 0.51 and 0.48 % in TT group (p < 0.001). Sagittal tibial tunnel midpoint distance ratio did not differ from sagittal graft insertion tibia midpoint distance of healthy knees in either group. Femoral tunnel clock position was better in AM [right knee 10:19 o'clock-face position (310° ± 4°); left knee 1:40 (50° ± 3°)] compared with TT group [right knee 10:48 (324° ± 5°); left knee 1:04 (32° ± 4°)]. With respect to the sagittal plane, the anterior-posterior position of femoral tunnel was

  18. Revision Risk After Allograft Anterior Cruciate Ligament Reconstruction: Association With Graft Processing Techniques, Patient Characteristics, and Graft Type.

    PubMed

    Tejwani, Samir G; Chen, Jason; Funahashi, Tadashi T; Love, Rebecca; Maletis, Gregory B

    2015-11-01

    Allograft tissue is a common graft choice for anterior cruciate ligament reconstruction (ACLR). Allograft sterilization methods vary widely across numerous commercial tissue vendors. Multiple studies, despite being limited in sample size, have suggested a higher rate of clinical failure associated with the use of allograft tissue in ACLR when compared with autograft. To examine the association of graft processing techniques, patient characteristics, and graft type with risk of revision surgery after allograft ACLR. Cohort study; Level of evidence, 3. A retrospective cohort study was conducted that used an integrated United States health care system's ACLR registry to identify primary unilateral cases in which allografts were used. Aseptic revision was the endpoint of the study. Allograft type, processing methods (irradiation dose, AlloWash, AlloTrue, BioCleanse), and graft donor age were assessed as potential risk factors for revision, with adjustment for patient age, sex, and body mass index (BMI) by use of survival analysis. Hazard ratios (HR) and 95% confidence intervals (CIs) were calculated. A total of 5968 primary ACLR cases with allograft were included in the study, of which 3688 (61.8%) were male patients. The median age of the cohort at the time of surgery was 34.1 years (interquartile range, 24.1-42.9 years). The mean time to follow-up (±SD) was 2.1 ± 1.5 years. There were 3751 (62.9%) allograft ACLRs using soft tissue, 1188 (19.9%) with Achilles tendon, and 1029 (17.2%) with bone-patellar tendon-bone (BPTB). Graft processing groups included BioCleanse (n = 367), AlloTrue or AlloWash (n = 2278), irradiation greater than 1.8 Mrad (n = 1146), irradiation up to 1.8 Mrad (n = 3637), and no irradiation (n = 1185). There were 156 (2.6%) aseptic revisions. After adjustment for patient age, sex, and BMI, the use of BioCleanse (HR = 2.45; 95% CI, 1.36-4.40) and irradiation greater than 1.8 Mrad (HR = 1.64; 95% CI, 1.08-2.49) were associated with a higher risk of

  19. Osteochondral autograft transplantation for juvenile osteochondritis dissecans of the knee: a series of twelve cases.

    PubMed

    Sasaki, Ken; Matsumoto, Tomoyuki; Matsushita, Takehiko; Kubo, Seiji; Ishida, Kazunari; Tei, Katsumasa; Akisue, Toshihiro; Kurosaka, Masahiro; Kuroda, Ryosuke

    2012-11-01

    The purpose of this study was to evaluate the clinical outcomes of osteochondral autograft transplantation (OAT) for juvenile osteochondritis dissecans (JOCD) lesions of the knee, especially time to return to sports. Twelve knee JOCD lesions with OCD grade 3 and 4 categorised by magnetic resonance imaging (MRI) were treated with OAT. Nine male and two female skeletally immature patients averaging 13.7 years old were included. The OCD lesions were assessed arthroscopically and then fixed in situ using multiple osteochondral plugs harvested under fluoroscopy from the distal femoral condyle without damaging the physis. International Cartilage Repair Society (ICRS) score and Lysholm score were assessed pre- and postoperatively. After a mean follow-up of 26.2 ± 15.1 months, the International Knee Documentation Committee (IKDC) subjective score significantly improved (p < 0.01). According to the IKDC score, objective assessment showed that ten of 12 (83 %) had excellent results (score: A) after OAT and significantly improved (p < 0.01). Based on ICRS criteria, results were satisfactory in all patients. No patients experienced complications at the graft harvest site. All patients returned to their previous level of athletic activity at an average of 5.7 months after the surgery. OAT for JOCD of the knee provided satisfactory results in all patients at a mean follow-up of 26.2 months.

  20. Comparison of Autograft and Allograft with Surface Modification for Flexor Tendon Reconstruction: A Canine in Vivo Model.

    PubMed

    Wei, Zhuang; Reisdorf, Ramona L; Thoreson, Andrew R; Jay, Gregory D; Moran, Steven L; An, Kai-Nan; Amadio, Peter C; Zhao, Chunfeng

    2018-04-04

    Flexor tendon injury is common, and tendon reconstruction is indicated clinically if the primary repair fails or cannot be performed immediately after tendon injury. The purpose of the current study was to compare clinically standard extrasynovial autologous graft (EAG) tendon and intrasynovial allogeneic graft (IAG) that had both undergone biolubricant surface modification in a canine in vivo model. Twenty-four flexor digitorum profundus (FDP) tendons from the second and fifth digits of 12 dogs were used for this study. In the first phase, a model of failed FDP tendon repair was created. After 6 weeks, the ruptured FDP tendons with a scarred digit were reconstructed with the use of either EAG or IAG tendons treated with carbodiimide-derivatized hyaluronic acid and lubricin. At 12 weeks after tendon reconstruction, the digits were harvested for functional, biomechanical, and histologic evaluations. The tendon failure model was a clinically relevant and reproducible model for tendon reconstruction. The IAG group demonstrated improved digit function with decreased adhesion formation, lower digit work of flexion, and improved graft gliding ability compared with the EAG group. However, the IAG group had decreased healing at the distal tendon-bone junction. Our histologic findings verified the biomechanical evaluations and, further, showed that cellular repopulation of allograft at 12 weeks after reconstruction is still challenging. FDP tendon reconstruction using IAG with surface modification has some beneficial effects for reducing adhesions but demonstrated inferior healing at the distal tendon-bone junction compared with EAG. These mixed results indicate that vitalization and turnover acceleration are crucial to reducing failure of reconstruction with allograft. Flexor tendon reconstruction is a common surgical procedure. However, postoperative adhesion formation may lead to unsatisfactory clinical outcomes. In this study, we developed a potential flexor tendon

  1. Femoral press-fit fixation in ACL reconstruction using bone-patellar tendon-bone autograft: results at 15 years follow-up.

    PubMed

    Widuchowski, Wojciech; Widuchowska, Malgorzata; Koczy, Bogdan; Dragan, Szymon; Czamara, Andrzej; Tomaszewski, Wieslaw; Widuchowski, Jerzy

    2012-06-27

    If anterior cruciate ligament (ACL) reconstruction is to be performed, decision regarding graft choice and its fixation remains one of the most controversial. Multiple techniques for ACL reconstruction are available. To avoid disadvantages related to fixation devices, a hardware-free, press-fit ACL reconstruction technique was developed. The aim of this study was to evaluate clinical outcome and osteoarthritis progression in long term after ACL reconstruction with central third patellar-tendon autograft fixed to femur by press-fit technique. Fifty two patients met inclusion/excusion criteria for this study. The patients were assessed preoperatively and at 15 years after surgery with International Knee Documentation Committee Knee Ligament Evaluation Form, Lysholm knee score, Tegner activity scale and radiographs. Good overall clinical outcomes and self-reported assessments were documented, and remained good at 15 years. The mean Lysholm and Tegner scores improved from 59.7 ± 18.5 and 4.2 ± 1.0 preoperatively to 86.4 ± 5.6 (p = 0.004) and 6.9 ± 1.4 (p = 0.005) respectively at follow-up. The IKDC subjective score improved from 60.1 ± 9.2 to 80.2 ± 8.1 (p = 0.003). According to IKDC objective score, 75% of patients had normal or nearly normal knee joints at follow-up. Grade 0 or 1 results were seen in 85% of patients on laxity testing. Degenerative changes were found in 67% of patients. There was no correlation between arthritic changes and stability of knee and subjective evaluation (p > 0.05). ACL reconstruction with patellar tendon autograft fixed to femur with press-fit technique allows to achieve good self-reported assessments and clinical ligament evaluation up to 15 years. Advantages of the bone-patellar-tendon-bone (BPTB) press-fit fixation include unlimited bone-to-bone healing, cost effectiveness, avoidance of disadvantages associated with hardware, and ease for revision surgery. BPTB femoral press-fit fixation technique can be safely applied in

  2. Reoperations on the pulmonary autograft and pulmonary homograft after the Ross procedure: An update on the German Dutch Ross Registry.

    PubMed

    Charitos, Efstratios I; Takkenberg, Johanna J M; Hanke, Thorsten; Gorski, Armin; Botha, Cornelius; Franke, Ulrich; Dodge-Khatami, Ali; Hoerer, Juergen; Lange, Rudiger; Moritz, Anton; Ferrari-Kuehne, Katharina; Hetzer, Roland; Huebler, Michael; Bogers, Ad J J C; Stierle, Ulrich; Sievers, Hans-Hinrich; Hemmer, Wolfgang

    2012-10-01

    Reinterventions after the Ross procedure are a concern for patients and treating physicians. The scope of the present report was to provide an update on the reinterventions observed in the large patient population of the German-Dutch Ross Registry. From 1988 to 2011, 2023 patients (age, 39.05 ± 16.5 years; male patients, 1502; adults, 1642) underwent a Ross procedure in 13 centers. The mean follow-up was 7.1 ± 4.6 years (range, 0-22 years; 13,168 patient-years). In the adult population, 120 autograft reinterventions in 113 patients (1.03%/patient-year) and 76 homograft reinterventions in 67 patients (0.65%/patient-year) and, in the pediatric population, 14 autograft reinterventions in 13 patients (0.91%/patient-year) and 42 homograft reinterventions in 31 patients (2.72%/patient-year) were observed. Of the autograft and homograft reinterventions, 17.9% and 21.2% were performed because of endocarditis, respectively. The subcoronary technique in the adult population resulted in significantly superior autograft durability (freedom from autograft reintervention: 97% at 10 years and 91% at 12 years; P < .001). The root replacement technique without root reinforcement (hazard ratio, 2.4; 95% confidence interval, 1.4-4.1) and the presence of pure aortic insufficiency preoperatively (hazard ratio, 2.3; 95% confidence interval, 1.5-3.5) were statistically significant predictors for a shorter time to reoperation. The center volume had a significant influence on the long-term results. The freedom from homograft reoperation for the adults and pediatric population was 97% and 87% at 5 years and 93% and 79% at 12 years, respectively (P < .001), with younger recipient and donor age being significant predictors of a shorter time to homograft reoperation. The autograft principle remains a valid option for young patients requiring aortic valve replacement. The risk of reoperation depends largely on the surgical technique used and the preoperative hemodynamics. Center

  3. Negative effect of rapidly resorbing properties of bioactive glass-ceramics as bone graft substitute in a rabbit lumbar fusion model.

    PubMed

    Lee, Jae Hyup; Ryu, Hyun-Seung; Seo, Jun-Hyuk; Lee, Do-Yoon; Chang, Bong-Soon; Lee, Choon-Ki

    2014-03-01

    Bioactive glass-ceramics have the ability to directly bind to bones and have been widely used as bone graft substitutes due to their high osteoconductivity and biocompatibility. CaO-SiO2-P2O5-B2O3 glass-ceramics are known to have good osteoconductivity and are used as bone graft extenders. This study aimed to evaluate the effects of the resorbing properties of glass-ceramics in bone fusion after producing and analyzing three types of CaO-SiO2-P2O5-B2O3 glass-ceramics with high osteoconductivity that had enhanced resorption by having an increased B2O3 content. The three types of CaO-SiO2-P2O5-B2O3 glass-ceramics with B2O3 contents of 8.0, 9.0, and 9.5 weight % were designated and grouped as P20B80, P10B90, and P5B95, respectively. Glass-ceramic types were tested for fusion rates and bone formation by employing the lumbar 5-6 intertransverse process fusion model in 51 New Zealand male rabbits. Bioactivity was assessed by soaking in simulated body fluid (SBF). In vitro study results showed sufficient hydroxycarbonate apatite layer formation occurred for P20B80 in1 day, for P10B90 in 3 days, and for P5B95 in 5 days after soaking in SBF. For the rabbit lumbar spine posterolateral fusion model, the autograft group recorded a 100% fusion rate with levels significantly higher than those of P20B80 (29.4%), P10B90 (0%), and P5B95 (14.3%), with high resorbing properties. Resorbing property differences among the three glass-ceramic groups were not significant. Histological results showed new bone formation confirming osteoconductivity in all three types of glass-ceramics. Radiomorphometric results also confirmed the resorbing properties of the three glass-ceramic types. The high resorbing properties and osteoconductivity of porous glass-ceramics can be advantageous as no glass-ceramics remain in the body. However, their relatively fast rate of resorption in the body negatively affects their role as an osteoconductive scaffold as glass-ceramics are resorbed before bony fusion.

  4. Irradiation autogenous mandibular grafts in primary reconstructions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hamaker, R.C.

    1981-07-01

    The procedure, irradiated mandibular autografts, for primary reconstruction, is presented with an immediate success rate of 88%. Eight cases have undergone primary mandibular reconstruction with the tumorous mandible irradiated to 10,000 rads in a single dose. The longest follow-up is 2 3/4 years. The autograft has proven to be an ideal implant. Major resections of the mandible in conjunction with large myocutaneous flaps have been reconstructed utilizing this implant.

  5. The effects of local insulin application to lumbar spinal fusions in a rat model.

    PubMed

    Koerner, John D; Yalamanchili, Praveen; Munoz, William; Uko, Linda; Chaudhary, Saad B; Lin, Sheldon S; Vives, Michael J

    2013-01-01

    The rates of pseudoarthrosis after a single-level spinal fusion have been reported up to 35%, and the agents that increase the rate of fusion have an important role in decreasing pseudoarthrosis after spinal fusion. Previous studies have analyzed the effects of local insulin application to an autograft in a rat segmental defect model. Defects treated with a time-released insulin implant had significantly more new bone formation and greater quality of bone compared with controls based on histology and histomorphometry. A time-released insulin implant may have similar effects when applied in a lumbar spinal fusion model. This study analyzes the effects of a local time-released insulin implant applied to the fusion bed in a rat posterolateral lumbar spinal fusion model. Our hypothesis was twofold: first, a time-released insulin implant applied to the autograft bed in a rat posterolateral lumbar fusion will increase the rate of successful fusion and second, will alter the local environment of the fusion site by increasing the levels of local growth factors. Animal model (Institutional Animal Care and Use Committee approved) using 40 adult male Sprague-Dawley rats. Forty skeletally mature Sprague-Dawley rats weighing approximately 500 g each underwent posterolateral intertransverse lumbar fusions with iliac crest autograft from L4 to L5 using a Wiltse-type approach. After exposure of the transverse processes and high-speed burr decortication, a Linplant (Linshin Canada, Inc., ON, Canada) consisting of 95% microrecrystalized palmitic acid and 5% bovine insulin (experimental group) or a sham implant consisting of only palmitic acid (control group) was implanted on the fusion bed with iliac crest autograft. As per the manufacturer, the Linplant has a release rate of 2 U/day for a minimum of 40 days. The transverse processes and autograft beds of 10 animals from the experimental and 10 from the control group were harvested at Day 4 and analyzed for growth factors. The

  6. Bioactive glass in cavitary bone defects: a comparative experimental study in rabbits

    PubMed Central

    Camargo, André Ferrari de França; Baptista, André Mathias; Natalino, Renato; de Camargo, Olavo Pires

    2015-01-01

    OBJECTIVES: To compare bioactive glass and autograft regarding their histomorphometric characteristics. METHODS: The authors conducted a prospective case-control experimental study on animals in order to compare the histomorphometric characteristics of bioactive glass versus autograft. Eight rabbits underwent surgery in which a cavitary defect was created in both proximal femurs. One side was filled with bioactive glass granules and the other, with autograft grafted from the contralateral side. The sides were randomized. Fourteen days after surgery, the animals were euthanized. RESULTS: Histologic analysis revealed that bone neoformation was equivalent among the two groups and the osteoblasts cell-count was higher in the femurs treated with bioactive glass. The osteocytes cell-count, however, was lower. The similarity in bone formation between both groups was consistent to literature findings. CONCLUSION: Bioactive glass is similar to autograft regarding bone neoformation in this animal model of cavitary bone defects. Level of Evidence III, Case-Control Study. PMID:26327802

  7. A Comparative Study of the Effect of Fibrin Glue versus Sutures on Clinical Outcome in Patients Undergoing Pterygium Excision and Conjunctival Autografts

    PubMed Central

    Cha, Dong Min; Kim, Kyeong Hwan; Choi, Hyuk Jin; Wee, Won Ryang

    2012-01-01

    Purpose To compare the effect of using fibrin glue or 10-0 nylon sutures on the clinical outcome of patients undergoing pterygium excision and conjunctival autografting. Methods We retrospectively reviewed the medical records of 52 eyes from 46 patients who underwent pterygium excision and conjunctival autografting and were followed up for more than 3 months. The operation duration, postoperative inflammation, complications, and recurrence rates were compared between groups of 20 patients (22 eyes) for whom fibrin glue was used (fibrin glue group) and 26 patients (30 eyes) for whom suturing was performed with 10-0 nylon (suture group) in pterygium excision and conjunctival autografting. Results The operation duration was 27.71 (5.22) minutes in the fibrin glue group and 43.30 (8.18) minutes in the suture group (p = 0.000). Seven days after the operation, the fibrin glue group showed milder conjunctival inflammation than the suture group (p = 0.000). Postoperative complications and corneal recurrence rates were not statistically different between the two groups. Conclusions The use of fibrin glue in pterygium excision with conjunctival autografting is likely to be a more effective, safer procedure than suturing. PMID:23204794

  8. Modeling conduction in host-graft interactions between stem cell grafts and cardiomyocytes.

    PubMed

    Chen, Michael Q; Yu, Jin; Whittington, R Hollis; Wu, Joseph C; Kovacs, Gregory T A; Giovangrandi, Laurent

    2009-01-01

    Cell therapy has recently made great strides towards aiding heart failure. However, while transplanted cells may electromechanically integrate into host tissue, there may not be a uniform propagation of a depolarization wave between the heterogeneous tissue boundaries. A model using microelectrode array technology that maps the electrical interactions between host and graft tissues in co-culture is presented and sheds light on the effects of having a mismatch of conduction properties at the boundary. Skeletal myoblasts co-cultured with cardiomyocytes demonstrated that conduction velocity significantly decreases at the boundary despite electromechanical coupling. In an attempt to improve the uniformity of conduction with host cells, differentiating human embryonic stem cells (hESC) were used in co-culture. Over the course of four to seven days, synchronous electrical activity was observed at the hESC boundary, implying differentiation and integration. Activity did not extend far past the boundary, and conduction velocity was significantly greater than that of the host tissue, implying the need for other external measures to properly match the conduction properties between host and graft tissue.

  9. Synthesis, characterization, and rheological studies of model water-soluble graft copolymers for application in enhanced oil recovery

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, L.S.

    1982-12-01

    Model water-soluble graft copolymers have been synthesized with acrylamide as the major grafting monomer and dextran as the substrate in order to define more clearly the structural parameters that are important in enhanced oil recovery applications. The structures of the model graft copolymer samples were studied by aqueous size exclusion chromatography, viscometry, elemental analysis, and selective hydrolysis of the graft copolymer backbone. The grafting systems with selected grafting monomers included Fe(II)/H/sub 2/O/sub 2/ with acrylamide, and Ce(IV)/HNO/sub 3/ with acrylamide, acrylamide/2-acrylamido-2-meth propane sulfonic acid, or acrylamide/diacetone acrylamide. The viscosity and pseudoplasticity of the resulting graft copolymers were affected by bothmore » total molecular weight and length of grafted chains; however, the latter was apparently more important when behavior was compared to linear counterparts.« less

  10. Return to Sports and Subsequent Injury Rates After Revision Anterior Cruciate Ligament Reconstruction With Patellar Tendon Autograft.

    PubMed

    Shelbourne, K Donald; Benner, Rodney W; Gray, Tinker

    2014-06-01

    The return-to-sport and reinjury rates are not well defined after revision anterior cruciate ligament (ACL) reconstruction. School-age athletes would have a higher rate of return to sports and reinjury to either knee after revision ACL surgery compared with college or recreational athletes. Cohort study; Level of evidence, 2. Patients were prospectively studied after revision ACL reconstruction with bone-patellar tendon-bone (BPTB) autograft. Participants were grouped by competitive sport levels of school age (mean age, 16.6 ± 0.9 years; n = 84), college (19.6 ± 1.2 years; n = 58), or recreational adult (27.6 ± 4.1 years; n = 117). An activity survey was used to determine the specific sport and sport level patients participated in before and after surgery. The International Knee Documentation Committee (IKDC) knee survey and Cincinnati Knee Rating System (CKRS) survey responses were also obtained. The rate of return to the same sport at the same level was 62 of 84 school-age athletes (74%), 43 of 58 college athletes (74%), and 73 of 117 recreational athletes (62%) (P = .1065). The number of patients who had a subsequent ACL graft tear rate after revision surgery was 2 of 84 (2.3%) in the high school group, 3 of 58 (5.1%) in the college group, and 4 of 117 (3.4%) in the recreational group (P = .6706). The number of patients who had a subsequent ACL tear in the contralateral knee was 1 of 84 (1.1%) in the school-age group, 1 of 58 (1.7%) in the college group, and 2 of 117 (1.7%) in the recreational group (P = .9501). At 2 years postoperatively, the mean IKDC subjective total score was 86.1 ± 11.7 points and the mean CKRS total score was 89.7 ± 11.1 points. Revision ACL reconstruction with BPTB autograft and perioperative rehabilitation allowed high school and college athletes to return to sports at the preinjury level at a rate of 74%; the return rate for recreational-level adults was 62%. Reinjury rates in the first 5 years after revision surgery ranged from 2

  11. Secure fixation of femoral bone plug with a suspensory button in anatomical anterior cruciate ligament reconstruction with bone-patellar tendon-bone graft

    PubMed Central

    TAKETOMI, SHUJI; INUI, HIROSHI; NAKAMURA, KENSUKE; YAMAGAMI, RYOTA; TAHARA, KEITARO; SANADA, TAKAKI; MASUDA, HIRONARI; TANAKA, SAKAE; NAKAGAWA, TAKUMI

    2015-01-01

    Purpose the efficacy and safety of using a suspensory button for femoral fixation in anatomical anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone (BPTB) graft have not been established. The purpose of the current study was to evaluate bone plug integration onto the femoral socket and migration of the bone plug and the EndoButton (EB) (Smith & Nephew, Andover, MA, USA) after rectangular tunnel ACL reconstruction with BPTB autograft. Methods thirty-four patients who underwent anatomical rectangular ACL reconstruction with BPTB graft using EB for femoral fixation and in whom three-dimensional (3D) computed tomography (CT) was performed one week and one year after surgery were included in this study. Bone plug integration onto the femoral socket, bone plug migration, soft tissue interposition, EB migration and EB rotation were evaluated on 3D CT. The clinical outcome was also assessed and correlated with the imaging outcomes. Results the bone plug was integrated onto the femoral socket in all cases. The incidence of bone plug migration, soft tissue interposition, EB migration and EB rotation was 15, 15, 9 and 56%, respectively. No significant association was observed between the imaging outcomes. The postoperative mean Lysholm score was 97.1 ± 5.0 points. The postoperative side-to-side difference, evaluated using a KT-2000 arthrometer, averaged 0.5 ± 1.3 mm. There were no complications associated with EB use. Imaging outcomes did not affect the postoperative KT side-to-side difference. Conclusions the EB is considered a reliable device for femoral fixation in anatomical rectangular tunnel ACL reconstruction with BPTB autograft. Level of evidence Level IV, therapeutic case series. PMID:26889465

  12. Late outcomes after grafting of the severely burned face: a quality improvement initiative.

    PubMed

    Philp, Lauren; Umraw, Nisha; Cartotto, Robert

    2012-01-01

    Many approaches to surgical management of the severely burned face are described, but there are few objective outcome studies. The purpose of this study was to perform a detailed evaluation of the late outcomes in adult patients who have undergone grafting using a standardized surgical and rehabilitation approach for full-thickness (FT) facial burns to identify areas for improvement in the treatment strategy of authors. This was a prospective observational study in which patients who had undergone grafting for FT facial burns by the senior investigator at a regional burn centre between 1999 and 2010 were examined by a single evaluator. The surgical approach included tangential excision based on the facial aesthetic units, temporary cover with allograft then autografting with scalp skin preferentially, split grafts for the upper eyelid, and FT grafts for the lower eyelid. Rehabilitation included compression (uvex and or soft cloth), scar massage, and silicone gel sheeting. Of 35 patients with facial grafts, 14 subjects (age 43 ± 16 years with 22 ± 21% TBSA burns) returned for late follow-up at 40 ± 33 months (range, 5-91 months). A mean of four facial aesthetic units per patient were grafted (range, 1-9 units), with six full facial grafts performed. Scalp was used as donor in 10 of 14 cases. Scalp donor sites were well tolerated with minor alopecia visible in only one case although the donor site visibly extended slightly past the hairline in two cases. Color match with native skin was rated at 8.8 ± 0.8 of 10 when scalp skin was used compared with 7.5 ± 1.6 with other donor sites (P = .06). On the lip and chin, hypertrophic scars were significantly worse compared with the rest of the facial grafts (Vancouver scar scale 8 ± 2 vs 3 ± 1, P < .01). Sensory recovery was poor with overall moving two-point discrimination at 11 ± 3 mm (range, 4-15 mm), and monofilament light touch was 3.8 ± 0.6. Graft borders were significantly more elevated than graft seams. On

  13. Validation of an image registration and segmentation method to measure stent graft motion on ECG-gated CT using a physical dynamic stent graft model

    NASA Astrophysics Data System (ADS)

    Koenrades, Maaike A.; Struijs, Ella M.; Klein, Almar; Kuipers, Henny; Geelkerken, Robert H.; Slump, Cornelis H.

    2017-03-01

    The application of endovascular aortic aneurysm repair has expanded over the last decade. However, the long-term performance of stent grafts, in particular durable fixation and sealing to the aortic wall, remains the main concern of this treatment. The sealing and fixation are challenged at every heartbeat due to downward and radial pulsatile forces. Yet knowledge on cardiac-induced dynamics of implanted stent grafts is sparse, as it is not measured in routine clinical follow-up. Such knowledge is particularly relevant to perform fatigue tests, to predict failure in the individual patient and to improve stent graft designs. Using a physical dynamic stent graft model in an anthropomorphic phantom, we have evaluated the performance of our previously proposed segmentation and registration algorithm to detect periodic motion of stent grafts on ECG-gated (3D+t) CT data. Abdominal aortic motion profiles were simulated in two series of Gaussian based patterns with different amplitudes and frequencies. Experiments were performed on a 64-slice CT scanner with a helical scan protocol and retrospective gating. Motion patterns as estimated by our algorithm were compared to motion patterns obtained from optical camera recordings of the physical stent graft model in motion. Absolute errors of the patterns' amplitude were smaller than 0.28 mm. Even the motion pattern with an amplitude of 0.23 mm was measured, although the amplitude of motion was overestimated by the algorithm with 43%. We conclude that the algorithm performs well for measurement of stent graft motion in the mm and sub-mm range. This ultimately is expected to aid in patient-specific risk assessment and improving stent graft designs.

  14. Compliant electrospun silk fibroin tubes for small vessel bypass grafting.

    PubMed

    Marelli, Benedetto; Alessandrino, Antonio; Farè, Silvia; Freddi, Giuliano; Mantovani, Diego; Tanzi, Maria Cristina

    2010-10-01

    Processing silk fibroin (SF) by electrospinning offers a very attractive opportunity for producing three-dimensional nanofibrillar matrices in tubular form, which may be useful for a biomimetic approach to small calibre vessel regeneration. Bypass grafting of small calibre vessels, with a diameter less than 6mm, is performed mainly using autografts, like the saphenous vein or internal mammary artery. At present no polymeric grafts made of SF are commercially available, mainly due to inadequate properties (low compliance and lack of endothelium cells). The aim of this work was to electrospin SF into tubular structures (Ø=6mm) for small calibre vessel grafting, characterize the morphological, chemico-physical and mechanical properties of the electrospun SF structures and to validate their potential to interact with cells. The morphological properties of electrospun SF nanofibres were investigated by scanning electron microscopy. Chemico-physical analyses revealed an increase in the crystallinity of the structure of SF nanofibres on methanol treatment. Mechanical tests, i.e. compliance and burst pressure measurements, of the electrospun SF tubes showed that the inner pressure to radial deformation ratio was linear for elongation up to 15% and pressure up to 400 mm Hg. The mean compliance value between 80 and 120 mm Hg was higher than the values reported for both Goretex(R) and Dacron(R) grafts and for bovine heterografts, but still slightly lower than those of saphenous and umbilical vein, which nowadays represent the gold standard for the replacement of small calibre arteries. The electrospun tubes resisted up to 575+/-17 mmHg, which is more than four times the upper physiological pressure of 120 mmHg and more than twice the pathological upper pressures (range 180-220 mmHg). The in vitro tests showed a good cytocompatibility of the electrospun SF tubes. Therefore, the electrospun SF tubes developed within this work represent a suitable candidate for small calibre

  15. An Injectable Hydrogel as Bone Graft Material with Added Antimicrobial Properties.

    PubMed

    Tommasi, Giacomo; Perni, Stefano; Prokopovich, Polina

    2016-06-01

    Currently, the technique which provides the best chances for a successful bone graft, is the use of bone tissue from the same patient receiving it (autograft); the main limitations are the limited availability and the risks involved in removing living bone tissue, for example, explant site pain and morbidity. Allografts and xenografts may overcome these limitations; however, they increase the risk of rejection. For all these reasons the development of an artificial bone graft material is particularly important and hydrogels are a promising alternative for bone regeneration. Gels were prepared using 1,4-butanediol diacrylate as crosslinker and alpha tricalciumphosphate; ZnCl2 and SrCl2 were added to the aqueous phase. MTT results demonstrated that the addition of strontium had a beneficial effect on the osteoblast cells density on hydrogels, and zinc instead did not increase osteoblast proliferation. The amount of calcium produced by the osteoblast cells quantified through the Alizarin Red protocol revealed that both strontium and zinc positively influenced the formation of calcium; furthermore, their effect was synergistic. Rheology properties were used to mechanically characterize the hydrogels and especially the influence of crosslinker's concentration on them, showing the hydrogels presented had extremely good mechanical properties. Furthermore, the antimicrobial activity of strontium and zinc in the hydrogels against methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis was determined.

  16. An Injectable Hydrogel as Bone Graft Material with Added Antimicrobial Properties

    PubMed Central

    Tommasi, Giacomo; Perni, Stefano

    2016-01-01

    Currently, the technique which provides the best chances for a successful bone graft, is the use of bone tissue from the same patient receiving it (autograft); the main limitations are the limited availability and the risks involved in removing living bone tissue, for example, explant site pain and morbidity. Allografts and xenografts may overcome these limitations; however, they increase the risk of rejection. For all these reasons the development of an artificial bone graft material is particularly important and hydrogels are a promising alternative for bone regeneration. Gels were prepared using 1,4-butanediol diacrylate as crosslinker and alpha tricalciumphosphate; ZnCl2 and SrCl2 were added to the aqueous phase. MTT results demonstrated that the addition of strontium had a beneficial effect on the osteoblast cells density on hydrogels, and zinc instead did not increase osteoblast proliferation. The amount of calcium produced by the osteoblast cells quantified through the Alizarin Red protocol revealed that both strontium and zinc positively influenced the formation of calcium; furthermore, their effect was synergistic. Rheology properties were used to mechanically characterize the hydrogels and especially the influence of crosslinker's concentration on them, showing the hydrogels presented had extremely good mechanical properties. Furthermore, the antimicrobial activity of strontium and zinc in the hydrogels against methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis was determined. PMID:27174392

  17. Antecedent thermal injury worsens split-thickness skin graft quality: A clinically relevant porcine model of full-thickness burn, excision and grafting.

    PubMed

    Carlsson, Anders H; Rose, Lloyd F; Fletcher, John L; Wu, Jesse C; Leung, Kai P; Chan, Rodney K

    2017-02-01

    Current standard of care for full-thickness burn is excision followed by autologous split-thickness skin graft placement. Skin grafts are also frequently used to cover surgical wounds not amenable to linear closure. While all grafts have potential to contract, clinical observation suggests that antecedent thermal injury worsens contraction and impairs functional and aesthetic outcomes. This study evaluates the impact of antecedent full-thickness burn on split-thickness skin graft scar outcomes and the potential mediating factors. Full-thickness contact burns (100°C, 30s) were created on the backs of anesthetized female Yorkshire Pigs. After seven days, burn eschar was tangentially excised and covered with 12/1000th inch (300μm) split-thickness skin graft. For comparison, unburned wounds were created by sharp excision to fat before graft application. From 7 to 120days post-grafting, planimetric measurements, digital imaging and biopsies for histology, immunohistochemistry and gene expression were obtained. At 120days post-grafting, the Observer Scar Assessment Scale, colorimetry, contour analysis and optical graft height assessments were performed. Twenty-nine porcine wounds were analyzed. All measured metrics of clinical skin quality were significantly worse (p<0.05) in burn injured wounds. Histological analysis supported objective clinical findings with marked scar-like collagen proliferation within the dermis, increased vascular density, and prolonged and increased cellular infiltration. Observed differences in contracture also correlated with earlier and more prominent myofibroblast differentiation as demonstrated by α-SMA staining. Antecedent thermal injury worsens split-thickness skin graft quality, likely by multiple mechanisms including burn-related inflammation, microscopically inadequate excision, and dysregulation of tissue remodeling. A valid, reliable, clinically relevant model of full-thickness burn, excision and skin replacement therapy has been

  18. Pilot Comparisons of Temporary Open Revascularization Using Stent Grafts vs. Standard Shunts in a Sheep (Ovis aries) Model

    DTIC Science & Technology

    2016-03-14

    using stent grafts vs. standard shunts in a sheep (Ovis aries) model." PRINCIPAL INVESTIGATOR (Pl) I TRAINING COORDINATOR (TC): Lt Col James Sampson...Objectives: Pilot study and development of an experimental model to test and compare the performance of endovascular stent -graft as an arterial shunt...FDG2015001 OA 2 Results: Exposure and placement of vascular stent -grafts and shunts into the common carotid artery was feasible. Stent -graft and

  19. A new model for studying the revascularization of skin grafts in vivo: the role of angiogenesis.

    PubMed

    Lindenblatt, Nicole; Calcagni, Maurizio; Contaldo, Claudio; Menger, Michael D; Giovanoli, Pietro; Vollmar, Brigitte

    2008-12-01

    Models of skin graft revascularization are based mostly on histologic evaluations but lack the possibility of analyzing the vascular biology in vivo. The aim of the present study was therefore to develop an animal model that allows continuous monitoring of the microcirculation during skin graft healing. Skin and subcutaneous tissue were removed from the back of dorsal skinfold chamber preparations in mice, leaving one layer of striated muscle and subcutaneous tissue as a wound bed (n = 5). A corresponding full-thickness skin graft was harvested from the groin and sutured into the defect in the back of the chamber. To study graft healing, repetitive intravital microscopy was performed during the first 10 days after engraftment. Capillary widening in the wound bed appeared at day 1 after grafting and increased until day 4. Capillary buds and sprouts first appeared at day 2. Blood filling of autochthonous graft capillaries occurred at day 3, resulting in almost complete restoration of the original skin microcirculation on day 5. This was achieved by interconnections between the microvasculature of the wound bed and the skin graft through a temporary angiogenic response. In principle, angiogenic blood vessel growth originated in the wound bed and was directed toward the graft. This new model allows for repetitive analysis of the microcirculation during skin graft healing. It provides ideal in vivo conditions to further delineate the exact mechanisms of blood vessel interconnection during the complex process of angiogenesis, and may also allow study of the vascularization of tissue-engineered skin substitutes.

  20. Treatment of aggressive multiple myeloma by high-dose chemotherapy and total body irradiation followed by blood stem cells autologous graft

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fermand, J.P.; Levy, Y.; Gerota, J.

    1989-01-01

    Eight patients with stage III aggressive multiple myeloma, refractory to current chemotherapy in six cases, were treated by high-dose chemotherapy (nitrosourea, etoposide, and melphalan) (HDC) and total body irradiation (TBI), followed by autografting with blood stem cells. These cells were previously collected by leukapheresis performed during hematologic recovery following cytotoxic drug-induced bone marrow aplasia. Seven patients were alive 9 to 17 months after HDC-TBI and graft. One died at day 40 from cerebral bleeding. All living patients achieved a 90% or greater reduction in tumor mass. In two cases, a complete remission (CR) has persisted at a follow-up of 15more » and 16 months. Three patients have been well and off therapy with stable minimal residual disease (RD) since 10, 11, and 17 months, respectively. A patient in apparent CR and another with RD have relapsed 9 to 12 months posttreatment. Autologous blood-derived hematopoietic stem cells induced successful and sustained engraftment in all living patients. These results, although still preliminary, indicate that HDC and TBI, followed by blood stem cells autograft, which has both practical and theoretical interest over allogeneic or autologous bone marrow transplantation, deserve consideration in selected patients with multiple myeloma.« less

  1. Utility of Adipocyte Fractions in Fat Grafting in an Athymic Rat Model.

    PubMed

    Akgul, Yucel; Constantine, Ryan; Bartels, Mason; Scherer, Philipp; Davis, Kathryn; Kenkel, Jeffrey M

    2018-05-02

    Multiple processing and handling methods of autologous fat yields to variations in graft retention and viability, which results in unpredictable clinical outcomes. This study aims to understand the skin effects of fat graft preparations that contain a varying ratio of free-lipid and stem-cell-bearing stromal vascular fractions (SVF). Lipoaspirates from consenting patients were processed into emulsified fat and then SVF and adipocyte fractions (free-lipid). SVF enriched with 0%, 5%, and 15% free-lipid were grafted along the dorsum of athymic rats. The xenografts were collected 45 days after grafting and then prepped for immunostaining. Xenografts resulted in viable tissue mass under the panniculus carnosus of rats as confirmed with human specific markers. A low percentage of human cells was also detected in the lower reticular dermis. Although grafts with SVF formed adipocytes of normal architecture, grafts formed with free-lipid alone resulted in large lipid vacuoles in varying sizes. Among graft preparations, SVF with 10% free-lipid resulted in much-developed adipocyte architecture with collagen and elastin. Compared with SVF alone grafts, SVF with free-lipid had higher CD44 expression, suggesting a localized immune response of adipocytes. Current studies suggest that SVF enriched with approximately 10% free-lipid provides the best conditions for fat graft differentiation into viable fat tissue formation as well as collagen and elastin production to provide mechanical support for overlaying skin in an athymic rat model. Additionally, application of this therapeutic modality in a simple clinical setting may offer a practical way to concentrate SVF with free-lipid in a small volume for the improvement of clinical defects.

  2. Complications and Adverse Events of a Randomized Clinical Trial Comparing 3 Graft Types for ACL Reconstruction.

    PubMed

    Mohtadi, Nicholas; Barber, Rhamona; Chan, Denise; Paolucci, Elizabeth Oddone

    2016-05-01

    Complications/adverse events of anterior cruciate ligament (ACL) surgery are underreported, despite pooled level 1 data in systematic reviews. All adverse events/complications occurring within a 2-year postoperative period after primary ACL reconstruction, as part of a large randomized clinical trial (RCT), were identified and described. Prospective, double-blind randomized clinical trial. Patients and the independent trained examiner were blinded to treatment allocation. University-based orthopedic referral practice. Three hundred thirty patients (14-50 years; 183 males) with isolated ACL deficiency were intraoperatively randomized to ACL reconstruction with 1 autograft type. Graft harvest and arthroscopic portal incisions were identical. Patients were equally distributed to patellar tendon (PT), quadruple-stranded hamstring tendon (HT), and double-bundle (DB) hamstring autograft ACL reconstruction. Adverse events/complications were patient reported, documented, and diagnoses confirmed. Two major complications occurred: pulmonary embolism and septic arthritis. Twenty-four patients (7.3%) required repeat surgery, including 25 separate operations: PT = 7 (6.4%), HT = 9 (8.2%), and DB = 8 (7.3%). Repeat surgery was performed for meniscal tears (3.6%; n = 12), intra-articular scarring (2.7%; n = 9), chondral pathology (0.6%; n = 2), and wound dehiscence (0.3%; n = 1). Other complications included wound problems, sensory nerve damage, muscle tendon injury, tibial periostitis, and suspected meniscal tears and chondral lesions. Overall, more complications occurred in the HT/DB groups (PT = 24; HT = 31; DB = 45), but more PT patients complained of moderate or severe kneeling pain (PT = 17; HT = 9; DB = 4) at 2 years. Overall, ACL reconstructive surgery is safe. Major complications were uncommon. Secondary surgery was necessary 7.3% of the time for complications/adverse events (excluding graft reinjury or revisions) within the first 2 years. Level 1 (therapeutic studies

  3. Impaction grafted bone chip size effect on initial stability in an acetabular model: Mechanical evaluation.

    PubMed

    Holton, Colin; Bobak, Peter; Wilcox, Ruth; Jin, Zhongmin

    2013-01-01

    Acetabular bone defect reconstruction is an increasing problem for surgeons with patients undergoing complex primary or revision total hip replacement surgery. Impaction bone grafting is one technique that has favourable long-term clinical outcome results for patients who undergo this reconstruction method for acetabular bone defects. Creating initial mechanical stability of the impaction bone graft in this technique is known to be the key factor in achieving a favourable implant survival rate. Different sizes of bone chips were used in this technique to investigate if the size of bone chips used affected initial mechanical stability of a reconstructed acetabulum. Twenty acetabular models were created in total. Five control models were created with a cemented cup in a normal acetabulum. Then five models in three different groups of bone chip size were constructed. The three groups had an acetabular protrusion defect reconstructed using either; 2-4 mm(3), 10 mm(3) or 20 mm(3) bone chip size for impaction grafting reconstruction. The models underwent compression loading up to 9500 N and displacement within the acetabular model was measured indicating the initial mechanical stability. This study reveals that, although not statistically significant, the largest (20 mm(3)) bone chip size grafted models have an inferior maximum stiffness compared to the medium (10 mm(3)) bone chip size. Our study suggests that 10 mm(3) size of bone chips provide better initial mechanical stability compared to smaller or larger bone chips. We dismissed the previously held opinion that the biggest practically possible graft is best for acetabular bone graft impaction.

  4. The Accumulation of miRNAs Differentially Modulated by Drought Stress Is Affected by Grafting in Grapevine1[OPEN

    PubMed Central

    Vitali, Marco; Vitulo, Nicola; Incarbone, Marco

    2017-01-01

    Grapevine (Vitis vinifera) is routinely grafted, and rootstocks inducing drought tolerance represent a source for adapting vineyards to climate change in temperate areas. Our goal was to investigate drought stress effects on microRNA (miRNA) abundance in a drought-resistant grapevine rootstock, M4 (Vitis vinifera × Vitis berlandieri), compared with a commercial cultivar, Cabernet Sauvignon, using their autografts and reciprocal grafts. RNA extracted from roots and leaves of droughted and irrigated plants of different graft combinations was used to prepare cDNA libraries for small RNA sequencing and to analyze miRNAs by quantitative real-time polymerase chain reaction (RT-qPCR). Measurements of leaf water potential, leaf gas exchange, and root hydraulic conductance attested that, under irrigation, M4 reduced water loss in comparison with cultivar Cabernet Sauvignon mostly through nonhydraulic, root-specific mechanisms. Under drought, stomatal conductance decreased at similar levels in the two genotypes. Small RNA sequencing allowed the identification of 70 conserved miRNAs and the prediction of 28 novel miRNAs. Different accumulation trends of miRNAs, observed upon drought and in different genotypes and organs, were confirmed by RT-qPCR. Corresponding target transcripts, predicted in silico and validated by RT-qPCR, often showed opposite expression profiles than the related miRNAs. Drought effects on miRNA abundance differed between the two genotypes. Furthermore, the concentration of drought-responsive miRNAs in each genotype was affected by reciprocal grafting, suggesting either the movement of signals inducing miRNA expression in the graft partner or, possibly, miRNA transport between scion and rootstock. These results open new perspectives in the selection of rootstocks for improving grapevine adaptation to drought. PMID:28235889

  5. A Comparative Study of Clinical Outcomes and Second-Look Arthroscopic Findings between Remnant-Preserving Tibialis Tendon Allograft and Hamstring Tendon Autograft in Anterior Cruciate Ligament Reconstruction: Matched-Pair Design.

    PubMed

    Kim, You Keun; Ahn, Jong Hyun; Yoo, Jae Doo

    2017-12-01

    This study aimed to compare stability, functional outcome, and second-look arthroscopic findings after anterior cruciate ligament reconstruction between remnant-preserving tibialis tendon allograft and remnant-sacrificing hamstring tendon autograft. We matched two groups (remnant-preserving tibialis tendon allograft group and hamstring tendon autograft group) in terms of demographic characteristics, associated injury, and knee characteristics. Each group consisted of 25 patients. Operation time was longer in the remnant-preserving tibialis tendon allograft group, but there was no significant intergroup difference in stability, clinical outcome, and second-look arthroscopic findings. When an autograft is not feasible in anterior cruciate ligament reconstruction, the remnant-preserving technique can produce comparable results in terms of restoration of function, stability of the knee, and degree of synovium coverage at second-look arthroscopy compared to remnant-sacrificing hamstring autograft.

  6. Early and mid-term results of autograft rescue by Ross reversal: A one-valve disease need not become a two-valve disease.

    PubMed

    Hussain, Syed T; Majdalany, David S; Dunn, Aaron; Stewart, Robert D; Najm, Hani K; Svensson, Lars G; Houghtaling, Penny L; Blackstone, Eugene H; Pettersson, Gösta B

    2018-02-01

    Risk of reoperation and loss of a second native valve are major drawbacks of the Ross operation. Rather than discarding the failed autograft, it can be placed back into the native pulmonary position by "Ross reversal." We review our early and mid-term results with this operation. From 2006 to 2017, 39 patients underwent reoperation for autograft dysfunction. The autograft was successfully rescued in 35 patients: by Ross reversal in 30, David procedure in 4, and autograft repair in 1. Medical records were reviewed for patient characteristics (mean age was 46 ± 13 years, range 18-67 years, and 23 were male), previous operations, indications for reoperation, hospital outcomes, and echocardiographic findings for the 30 patients undergoing successful Ross reversal. Follow-up was 4.1 ± 3.5 years (range 7 months-11 years). Median interval between the original Ross procedure and Ross reversal was 12 years (range 5-19 years). Eight patients also had absolute indications for replacement of the pulmonary allograft. There was no operative mortality. One patient required reoperation for bleeding. Another had an abdominal aorta injury from use of an endoballoon clamp. There was no other major postoperative morbidity, and median postoperative hospital stay was 7.2 days (range 4-41 days). No patient required reoperation during follow-up. Twenty-four patients had acceptable pulmonary valve function, and 6 had clinically well-tolerated moderate or severe pulmonary regurgitation. Ross reversal can be performed with low morbidity and acceptable pulmonary valve function, reducing patient risk of losing 2 native valves when the autograft fails in the aortic position. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  7. Anterior cervical corpectomy for cervical spondylotic myelopathy: Reconstruction with expandable cylindrical cage versus iliac crest autograft. A retrospective study.

    PubMed

    Perrini, Paolo; Gambacciani, Carlo; Martini, Carlotta; Montemurro, Nicola; Lepori, Paolo

    2015-12-01

    To compare retrospectively the clinical and radiographic outcomes between cervical reconstruction with expandable cylindrical cage (ECC) and iliac crest autograft after one- or two-level anterior cervical corpectomy for spondylotic myelopathy. Forty-two patients underwent cervical reconstruction with either iliac crest autograft and plating (20 patients) or ECC and plating (22 patients). The average clinical and radiological follow-up period was 77.54 ± 44.28 months (range 14-155 months). The authors compared clinical parameters (Nurick Myelopathy Grade, modified Japanese Orthopedic Association (mJOA) scores), perioperative parameters (hospital stays, complications) and radiological parameters (Cobb's angles of the fused segments and C2-C7 segments, cervical subsidence, fusion rate). Fusion was assessed on flexion-extension X-ray films. No significant differences between the two groups were found in demographics, neurological presentation, preoperative sagittal alignment, clinical improvement and length of hospitalization. Patients of the autograft group experienced more postoperative complications, although the difference between the two treatment groups was not statistically significant (15 versus 4.5%, p=0.232). The fusion rate was 100% in both groups. The average lordotic increase of the segmental angle was significantly greater in the ECC group (p<0.05). Other radiological parameters were not significantly different in the two groups. Cervical reconstruction either with iliac crest autograft and plating or ECC and plating provides good clinical results and similar fusion rates after one- or two-level corpectomy for spondylotic myelopathy. However, the use of ECC obviates donor site complications and provides a more significant increase of lordosis in segmental angle. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Impact of graft implantation order on graft survival in simultaneous pancreas-kidney transplantation.

    PubMed

    Niclauss, Nadja; Bédat, Benoît; Morel, Philippe; Andres, Axel; Toso, Christian; Berney, Thierry

    2016-05-01

    The optimal order of revascularization for pancreas and kidney grafts in simultaneous pancreas-kidney transplantation has not been established. In this study, we investigate the influence of graft implantation order on graft survival in SPK. 12 700 transplantations from the Scientific Registry of Transplant Recipients were analyzed retrospectively. Graft implantation order was determined based on the reported ischemia times of pancreas and kidney grafts. Pancreas and kidney graft survivals were analyzed depending on graft implantation order at 3 months and 5 years using Kaplan-Meier plots. Significance was tested with log-rank test and Cox regression model. In 8454 transplantations, the pancreas was implanted first (PBK), and in 4246 transplantations, the kidney was implanted first (KBP). The proportion of lost pancreas grafts at 3 months was significantly lower in PBK (9.4% vs. 10.8%, P = 0.011). Increasing time lag (>2 h) between kidney and pancreas graft implantation in KBP accentuated the detrimental impact on pancreas graft survival (12.5% graft loss at 3 months, P = 0.001). Technical failure rates were reduced in PBK (5.6 vs. 6.9%, P = 0.005). Graft implantation order had no impact on kidney graft survival. In summary, although observed differences are small, pancreas graft implantation first increases short-term pancreas graft survival and reduces rates of technical failure. © 2016 Steunstichting ESOT.

  9. Calcar bone graft

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bargar, W.L.; Paul, H.A.; Merritt, K.

    1986-01-01

    A canine model was developed to investigate the use of an autogeneic iliac bone graft to treat the calcar deficiency commonly found at the time of revision surgery for femoral component loosening. Five large male mixed-breed dogs had bilateral total hip arthroplasty staged at three-month intervals, and were sacrificed at six months. Prior to cementing the femoral component, an experimental calcar defect was made, and a bicortical iliac bone graft was fashioned to fill the defect. Serial roentgenograms showed the grafts had united with no resorption. Technetium-99 bone scans showed more uptake at three months than at six months inmore » the graft region. Disulfine blue injection indicated all grafts were perfused at both three and six months. Thin section histology, fluorochromes, and microradiographs confirmed graft viability in all dogs. Semiquantitative grading of the fluorochromes indicated new bone deposition in 20%-50% of each graft at three months and 50%-80% at six months. Although the calcar bone graft was uniformly successful in this canine study, the clinical application of this technique should be evaluated by long-term results in humans.« less

  10. [Acute transformation of chronic myeloid leukemia: disappearance of the Philadelphia chromosome after autograft].

    PubMed

    Reiffers, J; David, B; Bernard, P; Vezon, G; Marit, G; Moulinier, J; Broustet, A

    1984-04-12

    Two patients with chronic granulocytic leukemia (C.G.L.) undergoing transformation were treated by high dose chemotherapy and total body irradiation followed by autografting of hematopoietic stem cells collected and cryo-preserved at the time of diagnosis. Recovery of hematopoiesis was characterized by disappearance of the Philadelphia chromosome in most metaphases. A new approach of the management of C.G.L. is discussed.

  11. Intrastriatal Grafting of Chromospheres: Survival and Functional Effects in the 6-OHDA Rat Model of Parkinson's Disease

    PubMed Central

    Boronat-García, Alejandra; Palomero-Rivero, Marcela; Guerra-Crespo, Magdalena; Millán-Aldaco, Diana; Drucker-Colín, René

    2016-01-01

    Cell replacement therapy in Parkinson’s disease (PD) aims at re-establishing dopamine neurotransmission in the striatum by grafting dopamine-releasing cells. Chromaffin cell (CC) grafts produce some transitory improvements of functional motor deficits in PD animal models, and have the advantage of allowing autologous transplantation. However, CC grafts have exhibited low survival, poor functional effects and dopamine release compared to other cell types. Recently, chromaffin progenitor-like cells were isolated from bovine and human adult adrenal medulla. Under low-attachment conditions, these cells aggregate and grow as spheres, named chromospheres. Here, we found that bovine-derived chromosphere-cell cultures exhibit a greater fraction of cells with a dopaminergic phenotype and higher dopamine release than CC. Chromospheres grafted in a rat model of PD survived in 57% of the total grafted animals. Behavioral tests showed that surviving chromosphere cells induce a reduction in motor alterations for at least 3 months after grafting. Finally, we found that compared with CC, chromosphere grafts survive more and produce more robust and consistent motor improvements. However, further experiments would be necessary to determine whether the functional benefits induced by chromosphere grafts can be improved, and also to elucidate the mechanisms underlying the functional effects of the grafts. PMID:27525967

  12. Osteochondral Autograft Transplantation Surgery for Metacarpal Head Defects.

    PubMed

    Kitay, Alison; Waters, Peter M; Bae, Donald S

    2016-03-01

    Post-traumatic osteonecrosis of the metacarpal head is a challenging problem, particularly in younger patients in whom arthroplasty may not be a durable option. Although several osteochondral reconstructive options have been proposed, some are associated with considerable donor site morbidity and/or require the use of internal fixation. We present an application of osteochondral autograft transplantation surgery as a treatment option for focal metacarpal head lesions. An osteochondral plug from the non-weight-bearing articular surface of the knee is transferred and press-fit to resurface a focal metacarpal head defect. The technical pearls and pitfalls are reviewed, and an illustrative case is presented. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  13. Twenty-year analysis of autologous support of the pulmonary autograft in the Ross procedure.

    PubMed

    Skillington, Peter D; Mokhles, M Mostafa; Takkenberg, Johanna J M; O'Keefe, Michael; Grigg, Leeanne; Wilson, William; Larobina, Marco; Tatoulis, James

    2013-09-01

    The Ross procedure is seldom offered to adults less than 60 years of age who require aortic valve replacement except in a few high-volume centers with documented expertise. Inserting the pulmonary autograft as an unsupported root replacement may lead to increasing reoperations on the aortic valve in the second decade. Of 333 patients undergoing the Ross procedure between October 1992 and June 2012, the study group of 310 consecutive patients (mean age ± standard deviation, 39.3±12.7 years (limits 16-63) had the aortic root size adjusted to match the pulmonary autograft, which was inserted as a root replacement, with the aorta closed up around it to provide autologous support. The mean follow-up time was 9.4 years; the actuarial survival was 97% at 16 years; and freedom from the composite of all reoperations on the aortic valve and late echocardiographic-detected aortic regurgitation greater than mild was 95% at 5 years, 94% at 10 years, and 93% at 15 years. Overall freedom from all reoperations on aortic and pulmonary valves was 97% at 5 years, 94% at 10 years, and 93% at 15 years. All results were better for the patients presenting with predominant aortic stenosis (98% freedom at 15 years) than for those with aortic regurgitation (p=0.01). Autologous support of the pulmonary autograft leads to excellent results in the groups presenting with aortic stenosis and mixed aortic stenosis/regurgitation and to good results for those presenting with pure aortic regurgitation. The Ross procedure, using one of the proven, durable techniques available, should be considered for more widespread adoption. Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  14. Platelet-Rich Fibrin Improves the Viability of Diced Cartilage Grafts in a Rabbit Model.

    PubMed

    Göral, Ali; Aslan, Cem; Bolat Küçükzeybek, Betül; Işık, Dağhan; Hoşnuter, Mübin; Durgun, Mustafa

    2016-04-01

    Diced cartilage may be wrapped with synthetic or biological materials before grafting to a recipient site. These materials have unique advantages and disadvantages, and a gold standard is not available. The authors investigated the effects of platelet-rich fibrin (PRF) on the survival of cartilage grafts in a rabbit model. In this experimental study, diced cartilage pieces from the ears of 9 male rabbits were left unwrapped or were wrapped with PRF, oxidized regenerated cellulose, or fascia. Specimens then were placed into subcutaneous pockets prepared on the backs of the rabbits. The animals were sacrificed 2 months after the procedure, and the grafts were excised for macroscopic and histopathologic examination. The cartilage graft wrapped with PRF showed superior viability compared with the cartilage graft wrapped with oxidized regenerated cellulose. No significant differences were found among the other groups. The groups were not significantly different in terms of rates of inflammation, fibrosis, or vascularization. PRF enhances the viability of diced cartilage grafts and should be considered an appropriate biological wrapping material for cartilage grafting. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  15. Negative Effect of Rapidly Resorbing Properties of Bioactive Glass-Ceramics as Bone Graft Substitute in a Rabbit Lumbar Fusion Model

    PubMed Central

    Lee, Jae Hyup; Ryu, Hyun-Seung; Seo, Jun-Hyuk; Lee, Do-Yoon; Chang, Bong-Soon

    2014-01-01

    Background Bioactive glass-ceramics have the ability to directly bind to bones and have been widely used as bone graft substitutes due to their high osteoconductivity and biocompatibility. CaO-SiO2-P2O5-B2O3 glass-ceramics are known to have good osteoconductivity and are used as bone graft extenders. Methods This study aimed to evaluate the effects of the resorbing properties of glass-ceramics in bone fusion after producing and analyzing three types of CaO-SiO2-P2O5-B2O3 glass-ceramics with high osteoconductivity that had enhanced resorption by having an increased B2O3 content. The three types of CaO-SiO2-P2O5-B2O3 glass-ceramics with B2O3 contents of 8.0, 9.0, and 9.5 weight % were designated and grouped as P20B80, P10B90, and P5B95, respectively. Glass-ceramic types were tested for fusion rates and bone formation by employing the lumbar 5-6 intertransverse process fusion model in 51 New Zealand male rabbits. Bioactivity was assessed by soaking in simulated body fluid (SBF). Results In vitro study results showed sufficient hydroxycarbonate apatite layer formation occurred for P20B80 in1 day, for P10B90 in 3 days, and for P5B95 in 5 days after soaking in SBF. For the rabbit lumbar spine posterolateral fusion model, the autograft group recorded a 100% fusion rate with levels significantly higher than those of P20B80 (29.4%), P10B90 (0%), and P5B95 (14.3%), with high resorbing properties. Resorbing property differences among the three glass-ceramic groups were not significant. Histological results showed new bone formation confirming osteoconductivity in all three types of glass-ceramics. Radiomorphometric results also confirmed the resorbing properties of the three glass-ceramic types. Conclusions The high resorbing properties and osteoconductivity of porous glass-ceramics can be advantageous as no glass-ceramics remain in the body. However, their relatively fast rate of resorption in the body negatively affects their role as an osteoconductive scaffold as glass

  16. Traumatic graft rupture after primary and revision anterior cruciate ligament reconstruction: retrospective analysis of incidence and risk factors in 2915 cases.

    PubMed

    Schlumberger, Michael; Schuster, Philipp; Schulz, Martin; Immendörfer, Micha; Mayer, Philipp; Bartholomä, Jochen; Richter, Jörg

    2017-05-01

    To determine incidence and risk factors for traumatic graft rupture following primary and revision anterior cruciate ligament (ACL) reconstruction. All cases of isolated ACL reconstructions (primary or revision) performed at our institution between January 2007 and December 2010 were included. From this group of 2467 primary reconstructions (32.4 ± 12.2 years) and 448 revision reconstructions (33.0 ± 10.4 years), we identified all patients who underwent revision ACL reconstruction following traumatic graft rupture in further course and all patients who underwent contralateral primary ACL reconstruction until January 2014. Age, gender, time from index procedure and graft diameter (for hamstring autografts) were analysed in terms of being a potential risk factor for graft rupture. Within a follow-up period of 5.0 ± 1.1 years (3.0-7.0), a total of 82 traumatic graft ruptures were identified, resulting in an incidence of 2.8 %. Seventy-three cases were seen following primary reconstructions (3.0 %), and nine cases following revision reconstructions (2.0 %), respectively (n.s.). Age younger than 25 years was identified as a risk factor for both groups (p = 0.001 and p = 0.008; odds ratio 6.0 and 6.4, respectively). In primary reconstruction, male patients had a higher risk of graft rupture compared with females (3.7 vs. 1.6 %; p = 0.005), and the first year after index procedure was associated with a higher risk of graft rupture compared with the following (p < 0.001). Graft diameter did not influence the risk of graft rupture. Incidence of contralateral ACL rupture was 3.1 %, which was not different to the incidence of graft rupture ipsilaterally (n.s.). No statistically significant differences were seen between graft rupture incidence of primary and revision ACL reconstructions. Young age (<25 years) and short time to the index procedure (especially within the first year) were confirmed as risk factors for graft rupture in both groups. Male

  17. * A Rat Model for the In Vivo Assessment of Biological and Tissue-Engineered Valvular and Vascular Grafts.

    PubMed

    Sugimura, Yukiharu; Schmidt, Anna Kathrin; Lichtenberg, Artur; Assmann, Alexander; Akhyari, Payam

    2017-12-01

    The demand for an improvement of the biocompatibility and durability of vascular and valvular implants requires translational animal models to study the in vivo fate of cardiovascular grafts. In the present article, a review on the development and application of a microsurgical rat model of infrarenal implantation of aortic grafts and aortic valved conduits is provided. By refinement of surgical techniques and inclusion of hemodynamic considerations, a functional model has been created, which provides a modular platform for the in vivo assessment of biological and tissue-engineered grafts. Through optional addition of procalcific diets, disease-inducing agents, and genetic modifications, complex multimorbidity scenarios mimicking the clinical reality in cardiovascular patients can be simulated. Applying this model, crucial aspects of the biocompatibility, biofunctionality and degeneration of vascular and valvular implants in dependency on graft preparation, and modification as well as systemic antidegenerative treatment of the recipient have been and will be addressed.

  18. Effect of Impaction Sequence on Osteochondral Graft Damage: The Role of Repeated and Varying Loads

    PubMed Central

    Kang, Richard W.; Friel, Nicole A.; Williams, James M.; Cole, Brian J.; Wimmer, Markus A.

    2013-01-01

    Background Osteochondral autografts and allografts require mechanical force for proper graft placement into the defect site; however, impaction compromises the tissue. This study aimed to determine the effect of impaction force and number of hits to seat the graft on cartilage integrity. Hypothesis Under constant impulse conditions, higher impaction load magnitudes are more detrimental to cell viability, matrix integrity and collagen network organization and will result in proteoglycan loss and nitric oxide release. Study Design Controlled laboratory study Methods Osteochondral explants, harvested from fresh bovine trochleas, were exposed to a series of consistent impact loads delivered by a pneumatically driven device. Each plug received the same overall impulse of 7 Ns, reflecting the mean of 23 clinically inserted plugs. Impaction loads of 37.5N, 75N, 150N, and 300N were matched with 74, 37, 21, and 11 hits respectively. Following impaction, the plugs were harvested and cartilage was analyzed for cell viability, histology by safranin-o and picosirius red, and release of sulfated glycosaminoglycans and nitric oxide. Data were compared with non-impacted control. Results Impacted plugs had significantly lower cell viability than non-impacted plugs. A dose response relationship in loss of cell viability with respect to load magnitude was seen immediately and after 4 days but lost after 8 days. Histologic analysis revealed intact cartilage surface in all samples (loaded or control), with loaded samples showing alterations in birefringence. While the sulfated GAG release was similar across varying impaction loads, release of nitric oxide increased with increasing impaction magnitudes and time. Conclusions Impaction loading parameters have a direct effect on the time course of the viability of the cartilage in the graft tissue. Clinical Relevance Optimal loading parameters for surgical impaction of osteochondral grafts are those with lower load magnitudes and a greater

  19. Two-step grafting significantly enhances the survival of foetal dopaminergic transplants and induces graft-derived vascularisation in a 6-OHDA model of Parkinson's disease.

    PubMed

    Büchele, Fabian; Döbrössy, Máté; Hackl, Christina; Jiang, Wei; Papazoglou, Anna; Nikkhah, Guido

    2014-08-01

    Following transplantation of foetal primary dopamine (DA)-rich tissue for neurorestaurative treatment of Parkinson's disease (PD), only 5-10% of the functionally relevant DAergic cells survive both in experimental models and in clinical studies. The current work tested how a two-step grafting protocol could have a positive impact on graft survival. DAergic tissue is divided in two portions and grafted in two separate sessions into the same target area within a defined time interval. We hypothesized that the first graft creates a "DAergic" microenvironment or "nest" similar to the perinatal substantia nigra that stimulates and protects the second graft. 6-OHDA-lesioned rats were sequentially transplanted with wild-type (GFP-, first graft) and transgenic (GFP+, second graft) DAergic cells in time interims of 2, 5 or 9days. Each group was further divided into two sub-groups receiving either 200k (low cell number groups: 2dL, 5dL, 9dL) or 400k cells (high cell number groups: 2dH, 5dH, 9dH) as first graft. During the second transplantation, all groups received the same amount of 200k GFP+ cells. Controls received either low or high cell numbers in one single session (standard protocol). Drug-induced rotations, at 2 and 6weeks after grafting, showed significant improvement compared to the baseline lesion levels without significant differences between the groups. Rats were sacrificed 8weeks after transplantation for post-mortem histological assessment. Both two-step groups with the time interval of 2days (2dL and 2dH) showed a significantly higher survival of DAergic cells compared to their respective standard control group (2dL, +137%; 2dH, +47%). Interposing longer intervals of 5 or 9days resulted in the loss of statistical significance, neutralising the beneficial two-step grafting effect. Furthermore, the transplants in the 2dL and 2dH groups had higher graft volume and DA-fibre-density values compared to all other two-step groups. They also showed intense growth of

  20. Saddle-nose deformity repair with microplate-adapted costal cartilage.

    PubMed

    Eren, Fikret; Öksüz, Sinan; Melikoğlu, Cenk; Karagöz, Hüseyin; Ülkür, Ersin

    2014-08-01

    Nasal deformities affecting the bone and lower two-thirds of the nose due to the loss of septal height and tip support are defined as "saddle-nose" deformity. Reconstruction of a saddle-nose deformity essentially necessitates structural grafting. This article presents an alternative approach for correction of saddle-nose deformity using a microplate and costal cartilage. The results are compared with those of the previously applied costal cartilage repair methods. Between 2004 and 2013, 16 patients were treated with costal cartilage autografts. Of these 16 patients, 7 were treated with a microplate and costal cartilage autograft combination, 4 were treated with a costal cartilage autograft and Kirschner (K)-wire, and 5 were treated with onlay costal cartilage grafts. The mean follow-up periods were 16 months for group treated with microplate-adapted autologous costal cartilage, 12 months for the group treated with K-wire and autologous costal cartilage, and 16 months for the group treated with onlay costal cartilage. The patients treated with K-wire inserted cartilages and the patients treated onlay dorsal costal cartilages encountered complications such as extrusion of the wire and warping, respectively. The seven patients treated with microplate and dorsal onlay costal cartilage graft did not experience any infection, warping, or extrusion complication. The warping tendency of the costal cartilage autograft can be efficiently prevented without a prominent complication risk by using microplate-adapted costal cartilage grafts. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  1. Hemodynamic effects of spiral ePTFE prosthesis compared with standard arteriovenous graft in a carotid to jugular vein porcine model.

    PubMed

    Jahrome, Ommid K; Hoefer, Imo; Houston, Graeme J; Stonebridge, Peter A; Blankestijn, Peter J; Moll, Frans L; de Borst, Gert J

    2011-01-01

    The primary patency rate of arteriovenous (AV) grafts is limited by distal venous anastomosis stenosis or occlusion due to intimal hyperplasia associated with distal graft turbulence. The normal blood flow in native arteries is spiral laminar flow. Standard vascular grafts do not produce spiral laminar flow at the distal anastomosis. Vascular grafts which induce a spiral laminar flow distally result in lower turbulence, particularly near the vessel wall. This initial study compares the hemodynamic effects of a spiral flow-inducing graft and a standard graft in a new AV carotid to jugular vein crossover graft porcine model. Four spiral flow grafts and 4 control grafts were implanted from the carotid artery to the contralateral jugular vein in 4 pigs. Two animals were terminated after 48 hours and 2 at 14 days. Graft patency was assessed by selective catheter digital angiography, and the flow pattern was assessed by intraoperative flow probe and color Doppler ultrasound (CDU) measurements. The spiral grafts were also assessed at enhanced flow rates using an external roller pump to simulate increased flow rates that may occur during dialysis using a standard dialysis needle cannulation. The method increased the flow rate through the graft by 660 ml/min. The graft distal anastomotic appearances were evaluated by explant histopathology. All grafts were patent at explantation with no complications. All anastomoses were found to be wide open and showed no significant angiographic stenosis at the distal anastomosis in both spiral and control grafts. CDU examinations showed a spiral flow pattern in the spiral graft and double helix pattern in the control graft. No gross histopathological effects were seen in either spiral or control grafts. This porcine model is robust and allows hemodynamic flow assessment up to 14 days postimplantation. The spiral flow-inducing grafts produced and maintained spiral flow at baseline and enhanced flow rates during dialysis needle

  2. Distal radius reconstruction with vascularized proximal fibular autograft after en-bloc resection of recurrent giant cell tumor.

    PubMed

    Yang, Yun-Fa; Wang, Jian-Wei; Huang, Pin; Xu, Zhong-He

    2016-08-17

    Giant cell tumors (GCTs) located in the distal radius are likely to recur, and the treatment of such recurrent tumors is very difficult. Here, we report our clinical experience in distal radius reconstruction with vascularized proximal fibular autografts after en-bloc excision of the entire distal radius in 17 patients with recurrent GCT (RGCT) of the distal radius. All 17 patients with RGCT in distal radius underwent plain radiography and/or magnetic resonance imaging (MRI) of the distal radius as the initial evaluation after hospitalization. Then the distal radius were replaced by vascularized proximal fibular autografts after en-bloc RGCT resection. We assessed all patients by using clinical examinations, plain radiography of the wrist and chest, and Mayo wrist scores in the follow-ups. After an average follow-up of 4.3 years (range: 1.5-10.0 years), no lung metastasis or local recurrence was detected in any of the 17 patients. In total, 14 patients had excellent or good functional wrist scores, 16 were pain free or had occasional pain, and 15 patients returned to work. The mean range of motion of the wrist was 101° (flexion-extension), and the mean grip strength was 77.2 % of the contralateral normal hand. En-bloc excision of the entire distal radius and distal radius reconstruction with a vascularized proximal fibular autograft can effectively achieve local tumor control and preserve wrist function in patients with RGCT of the distal radius.

  3. Subrenal capsule grafting technology in human cancer modeling and translational cancer research.

    PubMed

    Wang, Yuzhuo; Wang, Joy X; Xue, Hui; Lin, Dong; Dong, Xin; Gout, Peter W; Gao, Xin; Pang, Jun

    2016-01-01

    Patient-derived xenograft (PDX) cancer models with high fidelity are in great demand. While the majority of PDXs are grafted under the skin of immunodeficient mice, the Living Tumor Laboratory (LTL), using unique subrenal capsule grafting techniques, has successfully established more than 200 transplantable PDX models of various low to high grade human cancers. The LTL PDX models retain key biological properties of the original malignancies, including histopathological and molecular characteristics, tumor heterogeneity, metastatic ability, and response to treatment. The PDXs are stored frozen at early transplant generations in a resurrectable form, which eliminates continuous passaging in mice, thus ensuring maintenance of the high biologic and molecular fidelity and reproducibility of the models. The PDX models have been demonstrated to be powerful tools for (i) studies of cancer progression, metastasis and drug resistance, (ii) evidenced-based precision cancer therapy, (iii) preclinical drug efficacy testing and discovery of new anti-cancer drug candidates. To better provide resources for the research community, an LTL website (www.livingtumorlab.com) has been designed as a publicly accessible database which allows researchers to identify PDX models suitable for translational/preclinical cancer research. In summary, subrenal capsule grafting technology maximizes both tumor engraftment rate and retention of human cancer heterogeneity. Moreover, the method makes possible the recovery of PDXs from frozen stocks for further applications, thus providing a powerful platform for translational cancer research. Copyright © 2015 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  4. Predictive models for ocular chronic graft-versus-host disease diagnosis and disease activity in transplant clinical practice.

    PubMed

    Curtis, Lauren M; Datiles, Manuel B; Steinberg, Seth M; Mitchell, Sandra A; Bishop, Rachel J; Cowen, Edward W; Mays, Jacqueline; McCarty, John M; Kuzmina, Zoya; Pirsl, Filip; Fowler, Daniel H; Gress, Ronald E; Pavletic, Steven Z

    2015-09-01

    Ocular chronic graft-versus-host disease is one of the most bothersome common complications following allogeneic hematopoietic stem cell transplantation. The National Institutes of Health Chronic Graft-versus-Host Disease Consensus Project provided expert recommendations for diagnosis and organ severity scoring. However, ocular chronic graft-versus-host disease can be diagnosed only after examination by an ophthalmologist. There are no currently accepted definitions of ocular chronic graft-versus-host disease activity. The goal of this study was to identify predictive models of diagnosis and activity for use in clinical transplant practice. A total of 210 patients with moderate or severe chronic graft-versus-host disease were enrolled in a prospective, cross-sectional, observational study (clinicaltrials.gov identifier: 00092235). Experienced ophthalmologists determined presence of ocular chronic graft-versus-host disease, diagnosis and activity. Measures gathered by the transplant clinician included Schirmer's tear test and National Institutes of Health 0-3 Eye Score. Patient-reported outcome measures were the ocular subscale of the Lee Chronic Graft-versus-Host Disease Symptom Scale and Chief Eye Symptom Intensity Score. Altogether, 157 (75%) patients were diagnosed with ocular chronic graft-versus-host disease; 133 of 157 patients (85%) had active disease. In a multivariable model, the National Institutes of Health Eye Score (P<0.0001) and Schirmer's tear test (P<0.0001) were independent predictors of ocular chronic graft-versus-host disease (sensitivity 93.0%, specificity 92.2%). The Lee ocular subscale was the strongest predictor of active ocular chronic graft-versus-host disease (P<0.0001) (sensitivity 68.5%, specificity 82.6%). Ophthalmology specialist measures that were most strongly predictive of diagnosis in a multivariate model were Oxford grand total staining (P<0.0001) and meibomian score (P=0.027). These results support the use of selected transplant

  5. Predictive models for ocular chronic graft-versus-host disease diagnosis and disease activity in transplant clinical practice

    PubMed Central

    Curtis, Lauren M.; Datiles, Manuel B.; Steinberg, Seth M.; Mitchell, Sandra A.; Bishop, Rachel J.; Cowen, Edward W.; Mays, Jacqueline; McCarty, John M.; Kuzmina, Zoya; Pirsl, Filip; Fowler, Daniel H.; Gress, Ronald E.; Pavletic, Steven Z.

    2015-01-01

    Ocular chronic graft-versus-host disease is one of the most bothersome common complications following allogeneic hematopoietic stem cell transplantation. The National Institutes of Health Chronic Graft-versus-Host Disease Consensus Project provided expert recommendations for diagnosis and organ severity scoring. However, ocular chronic graft-versus-host disease can be diagnosed only after examination by an ophthalmologist. There are no currently accepted definitions of ocular chronic graft-versus-host disease activity. The goal of this study was to identify predictive models of diagnosis and activity for use in clinical transplant practice. A total of 210 patients with moderate or severe chronic graft-versus-host disease were enrolled in a prospective, cross-sectional, observational study (clinicaltrials.gov identifier: 00092235). Experienced ophthalmologists determined presence of ocular chronic graft-versus-host disease, diagnosis and activity. Measures gathered by the transplant clinician included Schirmer’s tear test and National Institutes of Health 0–3 Eye Score. Patient-reported outcome measures were the ocular subscale of the Lee Chronic Graft-versus-Host Disease Symptom Scale and Chief Eye Symptom Intensity Score. Altogether, 157 (75%) patients were diagnosed with ocular chronic graft-versus-host disease; 133 of 157 patients (85%) had active disease. In a multivariable model, the National Institutes of Health Eye Score (P<0.0001) and Schirmer’s tear test (P<0.0001) were independent predictors of ocular chronic graft-versus-host disease (sensitivity 93.0%, specificity 92.2%). The Lee ocular subscale was the strongest predictor of active ocular chronic graft-versus-host disease (P<0.0001) (sensitivity 68.5%, specificity 82.6%). Ophthalmology specialist measures that were most strongly predictive of diagnosis in a multivariate model were Oxford grand total staining (P<0.0001) and meibomian score (P=0.027). These results support the use of selected

  6. Model For Bending Actuators That Use Electrostrictive Graft Elastomers

    NASA Technical Reports Server (NTRS)

    Costen, Robert C.; Su, Ji; Harrison, Joycelyn S.

    2001-01-01

    Recently, it was reported that an electrostrictive graft elastomer exhibits large electric field-induced strain (4%). Combined with its high mechanical modulus, the elastomer can offer very promising electromechanical properties, in terms of output mechanical energy density, for an electroactive polymeric material. Therefore, it has been considered as one of the candidates that can be used in high performance, low mass actuation devices in many aerospace applications. Various bilayer- based bending actuators have been designed and fabricated. An analytic model based on beam theory in the strength of materials has been derived for the transverse deflection, or curvature, and the longitudinal strain of the bi-layer beam. The curvature and strain are functions of the applied voltage and the thickness, width, and Young s modulus of the active and passive layers. The model can be used to optimize the performance of electrostrictive graft elastomer-based actuators to meet the requirements of various applications. In this presentation, optimization and sensitivity studies are applied to the bending performance of such actuators.

  7. Novel application and serial evaluation of tissue-engineered portal vein grafts in a murine model.

    PubMed

    Maxfield, Mark W; Stacy, Mitchel R; Kurobe, Hirotsugu; Tara, Shuhei; Yi, Tai; Cleary, Muriel A; Zhuang, Zhen W; Rodriguez-Davalos, Manuel I; Emre, Sukru H; Iwakiri, Yasuko; Shinoka, Toshiharu; Breuer, Christopher K

    2017-12-01

    Surgical management of pediatric extrahepatic portal vein obstruction requires meso-Rex bypass using autologous or synthetic grafts. Tissue-engineered vascular grafts (TEVGs) provide an alternative, but no validated animal models using portal TEVGs exist. Herein, we preclinically assess TEVGs as portal vein bypass grafts. TEVGs were implanted as portal vein interposition conduits in SCID-beige mice, monitored by ultrasound and micro-computed tomography, and histologically assessed postmortem at 12 months. TEVGs remained patent for 12 months. Histologic analysis demonstrated formation of neovessels that resembled native portal veins, with similar content of smooth muscle cells, collagen type III and elastin. TEVGs are feasible portal vein conduits in a murine model. Further preclinical evaluation of TEVGs may facilitate pediatric clinical translation.

  8. Modeling and optimization aspects of radiation induced grafting of 4-vinylpyridene onto partially fluorinated films

    NASA Astrophysics Data System (ADS)

    Nasef, Mohamed Mahmoud; Ahmad Ali, Amgad; Saidi, Hamdani; Ahmad, Arshad

    2014-01-01

    Modeling and optimization aspects of radiation induced grafting (RIG) of 4-vinylpyridine (4-VP) onto partially fluorinated polymers such as poly(ethylene-co-tetrafluoroethene) (ETFE) and poly(vinylidene fluoride) (PVDF) films were comparatively investigated using response surface method (RSM). The effects of independent parameters: absorbed dose, monomer concentration, grafting time and reaction temperature on the response, grafting yield (GY) were correlated through two quadratic models. The results of this work confirm that RSM is a reliable tool not only for optimization of the reaction parameters and prediction of GY in RIG processes, but also for the reduction of the number of the experiments, monomer consumption and absorbed dose leading to an improvement of the overall reaction cost.

  9. The effect of delayed graft function on graft and patient survival in kidney transplantation: an approach using competing events analysis.

    PubMed

    Fonseca, Isabel; Teixeira, Laetitia; Malheiro, Jorge; Martins, La Salete; Dias, Leonídio; Castro Henriques, António; Mendonça, Denisa

    2015-06-01

    In kidney transplantation, the impact of delayed graft function (DGF) on long-term graft and patient survival is controversial. We examined the impact of DGF on graft and recipient survival by accounting for the possibility that death with graft function may act as a competing risk for allograft failure. We used data from 1281 adult primary deceased-donor kidney recipients whose allografts functioned at least 1 year. The probability of graft loss occurrence is overestimated using the complement of Kaplan-Meier estimates (1-KM). Both the cause-specific Cox proportional hazard regression model (standard Cox) and the subdistribution hazard regression model proposed by Fine and Gray showed that DGF was associated with shorter time to graft failure (csHR = 2.0, P = 0.002; sHR = 1.57, P = 0.009), independent of acute rejection (AR) and after adjusting for traditional factors associated with graft failure. Regarding patient survival, DGF was a predictor of patient death using the cause-specific Cox model (csHR = 1.57, P = 0.029) but not using the subdistribution model. The probability of graft loss from competing end points should not be reported with the 1-KM. Application of a regression model for subdistribution hazard showed that, independent of AR, DGF has a detrimental effect on long-term graft survival, but not on patient survival. © 2015 Steunstichting ESOT.

  10. Minimally invasive repair of the tibialis anterior tendon using a semitendinosus autograft.

    PubMed

    Michels, Frederick; Van Der Bauwhede, Jan; Oosterlinck, Dirk; Thomas, Sam; Guillo, Stéphane

    2014-03-01

    Ruptures of the tibialis anterior tendon are rare but can cause substantial functional deficiencies. The literature regarding the treatment of such injuries is very limited. Atraumatic ruptures often occur in the presence of an abnormal tendon structure, and retraction often makes end-to-end repair impossible. With traumatic lesions, the risk of developing both adhesions and scar tissue is high. This study assesses the results of a surgical reconstruction using the interposition of a semitendinosus tendon autograft in 12 patients. Three patients had a traumatic rupture, and 9 patients had an atraumatic rupture. In 8 patients, the procedure was carried out using a minimally invasive technique. The average postoperative American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot score was 95.7 in the atraumatic group and 94.7 in the traumatic group. Active dorsiflexion was possible after 2 to 3 weeks. We believe that the interposition of a strong, healthy tendon facilitated healing and allowed early weight bearing. All patients had good recovery of dorsiflexion and gait. Repairing a ruptured tibialis anterior tendon using a semitendinosus autograft was a reliable technique and offered a good result. With the minimally invasive approach, there was no need to divide the extensor retinaculum, which we believe allowed faster recovery and reduced the risk of adhesions and wound healing problems. Level IV, retrospective case series.

  11. Repair of Segmental Bone Defect Using Totally Vitalized Tissue Engineered Bone Graft by a Combined Perfusion Seeding and Culture System

    PubMed Central

    Feng, Ya-Fei; Li, Xiang; Hu, Yun-Yu; Wang, Zhen; Ma, Zhen-Sheng; Lei, Wei

    2014-01-01

    Background The basic strategy to construct tissue engineered bone graft (TEBG) is to combine osteoblastic cells with three dimensional (3D) scaffold. Based on this strategy, we proposed the “Totally Vitalized TEBG” (TV-TEBG) which was characterized by abundant and homogenously distributed cells with enhanced cell proliferation and differentiation and further investigated its biological performance in repairing segmental bone defect. Methods In this study, we constructed the TV-TEBG with the combination of customized flow perfusion seeding/culture system and β-tricalcium phosphate (β-TCP) scaffold fabricated by Rapid Prototyping (RP) technique. We systemically compared three kinds of TEBG constructed by perfusion seeding and perfusion culture (PSPC) method, static seeding and perfusion culture (SSPC) method, and static seeding and static culture (SSSC) method for their in vitro performance and bone defect healing efficacy with a rabbit model. Results Our study has demonstrated that TEBG constructed by PSPC method exhibited better biological properties with higher daily D-glucose consumption, increased cell proliferation and differentiation, and better cell distribution, indicating the successful construction of TV-TEBG. After implanted into rabbit radius defects for 12 weeks, PSPC group exerted higher X-ray score close to autograft, much greater mechanical property evidenced by the biomechanical testing and significantly higher new bone formation as shown by histological analysis compared with the other two groups, and eventually obtained favorable healing efficacy of the segmental bone defect that was the closest to autograft transplantation. Conclusion This study demonstrated the feasibility of TV-TEBG construction with combination of perfusion seeding, perfusion culture and RP technique which exerted excellent biological properties. The application of TV-TEBG may become a preferred candidate for segmental bone defect repair in orthopedic and maxillofacial

  12. Open-Wedge High Tibial Osteotomy: RCT 2 Years RSA Follow-Up.

    PubMed

    Lind-Hansen, Thomas Bruno; Lind, Martin Carøe; Nielsen, Poul Torben; Laursen, Mogens Berg

    2016-11-01

    We investigated the influence of three different bone grafting materials on stability and clinical outcome of the healing open-wedge high tibial osteotomy (OW-HTO) with immediate partial weight bearing. A total of 45 (3 × 15) patients were randomized to injectable calcium phosphate cement (Calcibon; Biomet-Merck Biomaterials GmbH, Darmstadt, Germany), local bone autograft, or iliac crest autograft. Stability of the bony healing was evaluated with radiostereometric analysis (RSA) up to 24 months postoperatively. Clinical outcome was evaluated with the knee injury and osteoarthritis outcome score (KOOS). RSA revealed translations and rotations close to zero regardless of bone grafting material, with no statistically significant differences between the groups. Clinically, the Calcibon group had lower quality of life KOOS subscore at 2 years follow-up. We conclude that with a stable implant and 6 weeks of partial weight bearing, local autografting is sufficient to achieve solid bone consolidation following OW-HTO. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  13. Sequential MRI Study of Graft Integrity and Signal Following Pediatric All-epiphyseal ACL Reconstruction: Does the “Sharp Turn” at the Socket of the Distal Femoral Aperture Matter?

    PubMed Central

    Tuca, Maria; Greditzer, Harry Gus; Gausden, Elizabeth Bishop; Uppstrom, Tyler J.; Potter, Hollis G.; Cordasco, Frank A.; Green, Daniel W.

    2017-01-01

    Objectives: To analyze graft structure and signal with particular emphasis on the distal femoral socket aperture following all-epiphyseal ACLR using hamstring autografts with sequential MRI in skeletally immature athletes. Methods: Retrospective cohort study of 23 skeletally immature patients who underwent ACLR by the same surgical team at a tertiary center during 2011-2013. Athletes had at least two follow-up MRIs, the first MRI 6-12 months after surgery and the second MRI >18 months, were included. Exclusion criteria included those athletes with inMRI follow-up (6) or with a failure of their reconstructions (1). All athletes were treated with an arthroscopic all-inside, all-epiphyseal ACLR, using hamstring autograft, secured with adjustable loop cortical buttons on both tibia and femur. MRI images were analyzed independently and blinded by an orthopaedic surgery fellow and a musculoskeletal radiology fellow. Using a GE Functional Analysis Software, the signal intensity (SI) of the graft was measured in 5 different locations: 1) femoral tunnel, 2) intra-articular proximal turn, 3) midsubstance, 4) intra-articular distal turn, and 5) tibial tunnel. Values were normalized to cortical bone density. The amount of perigraft scarring and synovitis was analyzed. An intraclass correlation coefficient was used to quantify inter-rater reliability, non-parametric Wilcoxon test for perigraft scarring and synovitis, one-way ANOVA to test if significant differences of SI were seen between the different graft locations, and a 2-tailed student t-test for SI changes from 1st to 2nd MRI. Results: The study included 16 patients (5 girls and 11 boys), with an average age at surgery of 11.9 years (range 10-15). The first follow-up MRI was on average at 8.4 months (range 6-12 months), while the 2nd MRI was on average 30.7 months (range 18-40) after surgery. Intra-class correlation coefficients were above 0.7 for all measurements, indicating an excellent concordance between observers

  14. Computer-aided osteotomy design for harvesting autologous bone grafts in reconstructive surgery

    NASA Astrophysics Data System (ADS)

    Krol, Zdzislaw; Zerfass, Peter; von Rymon-Lipinski, Bartosz; Jansen, Thomas; Hauck, Wolfgang; Zeilhofer, Hans-Florian U.; Sader, Robert; Keeve, Erwin

    2001-05-01

    Autologous grafts serve as the standard grafting material in the treatment of maxillofacial bone tumors, traumatic defects or congenital malformations. The pre-selection of a donor site depends primarily on the morphological fit of the available bone mass and the shape of the part that has to be transplanted. To achieve sufficient incorporation of the autograft into the host bone, precise planning and simulation of the surgical intervention based on 3D CT studies is required. This paper presents a method to identify an optimal donor site by performing an optimization of appropriate similarity measures between donor region and a given transplant. At the initial stage the surgeon has to delineate the osteotomy border lines in the template CT data set and to define a set of constraints for the optimization of appropriate similarity measures between donor region and a given transplant. At the initial stage the surgeon has to delineate the osteotomy border lines in the template CT data set and to define a set of constraints for the optimization task in the donor site CT data set. The following fully automatic optimization stage delivers a set of sub-optimal and optimal donor sites for a given template. All generated solutions can be explored interactively on the computer display using an efficient graphical interface. Reconstructive operations supported by our system were performed on 28 patients. We found that the operation time can be considerably shortened by this approach.

  15. Air Pump-Assisted Graft Centration, Graft Edge Unfolding, and Graft Uncreasing in Young Donor Graft Pre-Descemet Endothelial Keratoplasty.

    PubMed

    Jacob, Soosan; Narasimhan, Smita; Agarwal, Amar; Agarwal, Athiya; A I, Saijimol

    2017-08-01

    To assess an air pump-assisted technique for graft centration, graft edge unfolding, and graft uncreasing while performing pre-Descemet endothelial keratoplasty (PDEK) using young donor grafts. Continuous pressurized air infusion was used for graft centration, graft edge unfolding, and graft unwrinkling. Ten eyes of 10 patients underwent PDEK with donors aged below 40 years. In all eyes, the donor scrolled into tight scrolls. In all cases, the air pump-assisted technique was effective in positioning and centering the graft accurately and in straightening infolded graft edges and smoothing out graft creases and wrinkles. Endothelial cell loss was 38.6%. Postoperative best-corrected visual acuity at 6 months was 0.66 ± 0.25 in decimal equivalent. Continuous pressurized air infusion acted as a third hand providing a continuous pressure head that supported the graft and prevented graft dislocation as well as anterior chamber collapse during intraocular maneuvering. Adequate maneuvering space was available in all cases, and bleeding, if any, was tamponaded successfully in all cases. Although very young donor grafts may be used for PDEK, they are difficult to center and unroll completely before floating against host stroma. An air pump-assisted technique using continuous pressurized air infusion allows successful final graft positioning even with very young donor corneas. It thus makes surgery easier as several key steps are made easier to handle. It additionally helps in tamponading hemorrhage during peripheral iridectomy, increasing surgical space, preventing fluctuations in the anterior chamber depth, and promoting graft adherence.

  16. Restoring Function after Volumetric Muscle Loss: Extracellular Matrix Allograft or Minced Muscle Autograft

    DTIC Science & Technology

    2017-10-01

    at the site of the VML. Prior small and large animal studies in our laboratory have demonstrated that minced muscle autograft (MMA), by virtue of...minced and placed intramuscularly at the site of the VML. Prior small and large animal studies in our laboratory have demonstrated that minced muscle...significant delay in the project initiation. First, a large animal study at the ISR indicated some concerns with the extra cellular matrix allograft that

  17. Acellular porcine intestinal submucosa as fascial graft in an animal model: applications for revision tympanoplasty.

    PubMed

    Ort, Stuart A; Ehrlich, H Paul; Isaacson, Jon E

    2010-09-01

    To demonstrate regeneration of muscle fascia appropriate for future harvest with the use of acellular porcine intestinal submucosa in a rat model. Animal cohort study. Tertiary care academic medical center. Sixteen male Sprague-Dawley rats underwent excision of rectus abdominis muscle fascia. A sheet of acellular porcine intestinal submucosa was placed in the fascia harvest defect. Graft and underlying muscle were harvested at three-, six-, and nine-week intervals. Histologic examination, including immunohistology for anti-von Willebrand factor, was performed at each timepoint. Additional selected specimens were subjected to latex vascular perfusion casts to examine vessel growth patterns within the graft. Gross examination revealed a new tissue plane, indistinguishable from surrounding native fascia. Histology revealed an initial inflammatory response within the graft. Progressive influx of native tissue was noted over successive timepoints. Via collagen-specific staining, we noted progressive reorganization and maturation of the graft collagen matrix. At the final nine-week time point, a new loose connective tissue plane was reestablished between the graft and underlying muscle. Immunohistochemistry and latex perfusion both demonstrate an initial development of small capillaries that progresses over time to greater organization and arteriole formation. Fascia regeneration may be possible with use of an acellular porcine intestinal submucosa graft in an animal model. Future studies may prove beneficial in restoring fascia in humans. Implications for potential advantages in tympanoplasty are discussed. Copyright 2010 American Academy of Otolaryngology-Head and Neck Surgery Foundation. Published by Mosby, Inc. All rights reserved.

  18. Effects of a Fibrin Sealant on Skin Graft Tissue Adhesion in a Rodent Model.

    PubMed

    Balceniuk, Mark D; Wingate, Nicholas A; Krein, Howard; Curry, Joseph; Cognetti, David; Heffelfiner, Ryan; Luginbuhl, Adam

    2016-07-01

    To establish a rodent model for skin grafting with fibrin glue and examine the effects of fibrin glue on the adhesive strength of skin grafts without bolsters. Animal cohort. Academic hospital laboratory. Three skin grafts were created using a pneumatic microtome on the dorsum of 12 rats. Rats were evenly divided into experimental (n = 6) and control (n = 6) groups. The experimental group received a thin layer of fibrin glue between the graft and wound bed, and the control group was secured with standard bolsters. Adherence strength of the skin graft was tested by measurement of force required to sheer the graft from the recipient wound. Adhesion strength measurements were taken on postoperative days (PODs) 1, 2, and 3. The experimental group required an average force of 719 g on POD1, 895 g on POD2, and 676 g on POD3, while the average force in the control group was 161 g on POD1, 257 g on POD2, and 267 g on POD3. On each of the 3 PODs, there was a significant difference in adherence strength between the experimental and control groups (P = .036, P = .029, P = .024). There is a significant difference in the adhesion strength of skin grafts to the wound bed in the early postoperative period of the 2 groups. In areas of high mobility, using the fibrin sealant can keep the graft immobile during the critical phases of early healing. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  19. In Vivo Bone Formation Within Engineered Hydroxyapatite Scaffolds in a Sheep Model.

    PubMed

    Lovati, A B; Lopa, S; Recordati, C; Talò, G; Turrisi, C; Bottagisio, M; Losa, M; Scanziani, E; Moretti, M

    2016-08-01

    Large bone defects still represent a major burden in orthopedics, requiring bone-graft implantation to promote the bone repair. Along with autografts that currently represent the gold standard for complicated fracture repair, the bone tissue engineering offers a promising alternative strategy combining bone-graft substitutes with osteoprogenitor cells able to support the bone tissue ingrowth within the implant. Hence, the optimization of cell loading and distribution within osteoconductive scaffolds is mandatory to support a successful bone formation within the scaffold pores. With this purpose, we engineered constructs by seeding and culturing autologous, osteodifferentiated bone marrow mesenchymal stem cells within hydroxyapatite (HA)-based grafts by means of a perfusion bioreactor to enhance the in vivo implant-bone osseointegration in an ovine model. Specifically, we compared the engineered constructs in two different anatomical bone sites, tibia, and femur, compared with cell-free or static cell-loaded scaffolds. After 2 and 4 months, the bone formation and the scaffold osseointegration were assessed by micro-CT and histological analyses. The results demonstrated the capability of the acellular HA-based grafts to determine an implant-bone osseointegration similar to that of statically or dynamically cultured grafts. Our study demonstrated that the tibia is characterized by a lower bone repair capability compared to femur, in which the contribution of transplanted cells is not crucial to enhance the bone-implant osseointegration. Indeed, only in tibia, the dynamic cell-loaded implants performed slightly better than the cell-free or static cell-loaded grafts, indicating that this is a valid approach to sustain the bone deposition and osseointegration in disadvantaged anatomical sites.

  20. Connective tissue changes in a mouse model of vein graft disease.

    PubMed

    Schachner, T; Heiss, S; Mayr, T; Steger, C; Zipponi, D; Reisinger, P; Bonaros, N; Laufer, G; Bonatti, J

    2008-04-01

    The extracellular matrix plays an important physiological role in the architecture of the vascular wall. In arterialized vein grafts severe early changes, such as thrombosis and neointimal hyperplasia occur. Paclitaxel is in clinical use as antiproliferative coating of coronary stents. We aimed to investigate the early connective tissue changes in arterialized vein grafts and the influence of perivascular paclitaxel treatment in an in vivo model. C57 black mice underwent interposition of the vena cava into the carotid artery. Neointimal hyperplasia, thrombosis, acid mucopolysaccharides (Alcian), collagen fibers (trichrome Masson), elastic fibers, and apoptosis rate (TUNEL) were quantified in paclitaxel treated veins and controls. In both, controls and paclitaxel treated vein grafts acid mucopolysaccharides and elastic fibers were found predominantly in the neointima, whereas collagen fibers were found mainly in the media and adventitia. At 4 weeks postoperatively the neointimal thickness in controls was 52 (13-130) microm, whereas in 0.6 mg/mL l paclitaxel treated veins it was 103 (43-318) microm (P=0.094). At 8 weeks postoperatively paclitaxel treated veins showed a significantly increased neointimal thickness of 136 (87-199) microm compared with 79 (62-146) microm in controls (P=0.032). There was no difference in apoptosis rate between the two groups (P=NS). Even with the lowest concentration of 0.008 mg/mL paclitaxel veins showed a neointimal thickness of 67 (46-205) microm at 4 weeks postoperatively (P=NS vs controls). Early vein graft disease is characterised by an accumulation of acid mucopolysaccharides and elastic fibers in the thickened neointima. Paclitaxel treatment increases the neointimal hyperplasia in mouse vein grafts in vivo.

  1. The effect of graft strength on knee laxity and graft in-situ forces after posterior cruciate ligament reconstruction.

    PubMed

    Lai, Yu-Shu; Chen, Wen-Chuan; Huang, Chang-Hung; Cheng, Cheng-Kung; Chan, Kam-Kong; Chang, Ting-Kuo

    2015-01-01

    Surgical reconstruction is generally recommended for posterior cruciate ligament (PCL) injuries; however, the use of grafts is still a controversial problem. In this study, a three-dimensional finite element model of the human tibiofemoral joint with articular cartilage layers, menisci, and four main ligaments was constructed to investigate the effects of graft strengths on knee kinematics and in-situ forces of PCL grafts. Nine different graft strengths with stiffness ranging from 0% (PCL rupture) to 200%, in increments of 25%, of an intact PCL's strength were used to simulate the PCL reconstruction. A 100 N posterior tibial drawer load was applied to the knee joint at full extension. Results revealed that the maximum posterior translation of the PCL rupture model (0% stiffness) was 6.77 mm in the medial compartment, which resulted in tibial internal rotation of about 3.01°. After PCL reconstruction with any graft strength, the laxity of the medial tibial compartment was noticeably improved. Tibial translation and rotation were similar to the intact knee after PCL reconstruction with graft strengths ranging from 75% to 125% of an intact PCL. When the graft's strength surpassed 150%, the medial tibia moved forward and external tibial rotation greatly increased. The in-situ forces generated in the PCL grafts ranged from 13.15 N to 75.82 N, depending on the stiffness. In conclusion, the strength of PCL grafts have has a noticeable effect on anterior-posterior translation of the medial tibial compartment and its in-situ force. Similar kinematic response may happen in the models when the PCL graft's strength lies between 75% and 125% of an intact PCL.

  2. Fat Layer from Medullary Canal Reamer Aspirate for Potential Use as a Supplemental Osteoinductive Bone Graft Material.

    PubMed

    Sinclair, Sarina S Kay; Horton, C Olsen; Jeray, Kyle J; Tanner, Stephanie L; Burgl, Karen J L

    2015-01-01

    Mesenchymal stem cells (MSCs) are of therapeutic interest to clinicians and researchers, as they have been shown to augment the osteogenic properties of bone grafts. MSCs are known to be prevalent in bone marrow, but are still limited in numbers. Hence, additional sources of MSCs are beneficial to increasing grafting potential. Aspirate material collected using the Reamer/Irrigator/Aspirator (RIA) device (Synthes; Paoli, PA) during reaming of the femoral shaft consists of three main components: bone fragments, liquid flow-through, and a fat layer. Currently, only the bone and liquid layers have been examined for osteoinductive elements, and the bone fragments are exclusively used as autologous bone graft. In the present study, a method to promote cellular outgrowth, tapping proliferative capacity from the previously discarded fatty layer of RIA aspirate, is described. Proliferating cells were successfully isolated from the bone and fatty layers of a consenting patient and found to be viable after liquid nitrogen storage. The osteogenic differentiation potential of the cells isolated from the fat and bone layers was assessed. Cells from both layers of the aspirate expressed statistically significant levels (p < 0.05) of the bone cell marker alkaline phosphatase compared to the control cells, suggesting differentiation along the osteoblastic pathway. Results from this pilot study indicate that the traditionally discarded fatty element of RIA aspirate may be a source of MSCs with bone-forming capabilities and the described isolation technique is effective. Combining the aspirate fatty and bony elements may enhance the clinical success of the RIA autograft.

  3. Effect of bidispersity in grafted chain length on grafted chain conformations and potential of mean force between polymer grafted nanoparticles in a homopolymer matrix.

    PubMed

    Nair, Nitish; Wentzel, Nathaniel; Jayaraman, Arthi

    2011-05-21

    In efforts to produce polymeric materials with tailored physical properties, significant interest has grown around the ability to control the spatial organization of nanoparticles in polymer nanocomposites. One way to achieve controlled particle arrangement is by grafting the nanoparticle surface with polymers that are compatible with the matrix, thus manipulating the interfacial interactions between the nanoparticles and the polymer matrix. Previous work has shown that the molecular weight of the grafted polymer, both at high grafting density and low grafting density, plays a key role in dictating the effective inter-particle interactions in a polymer matrix. At high grafting density nanoparticles disperse (aggregate) if the graft molecular weight is higher (lower) than the matrix molecular weight. At low grafting density the longer grafts can better shield the nanoparticle surface from direct particle-particle contacts than the shorter grafts and lead to the dispersion of the grafted particles in the matrix. Despite the importance of graft molecular weight, and evidence of non-trivial effects of polydispersity of chains grafted on flat surfaces, most theoretical work on polymer grafted nanoparticles has only focused on monodisperse grafted chains. In this paper, we focus on how bidispersity in grafted chain lengths affects the grafted chain conformations and inter-particle interactions in an implicit solvent and in a dense homopolymer polymer matrix. We first present the effects of bidispersity on grafted chain conformations in a single polymer grafted particle using purely Monte Carlo (MC) simulations. This is followed by calculations of the potential of mean force (PMF) between two grafted particles in a polymer matrix using a self-consistent Polymer Reference Interaction Site Model theory-Monte Carlo simulation approach. Monte Carlo simulations of a single polymer grafted particle in an implicit solvent show that in the bidisperse polymer grafted particles

  4. Is quadriceps tendon a better graft choice than patellar tendon? a prospective randomized study.

    PubMed

    Lund, Bent; Nielsen, Torsten; Faunø, Peter; Christiansen, Svend Erik; Lind, Martin

    2014-05-01

    The purpose of this randomized controlled study was to compare knee stability, kneeling pain, harvest site pain, sensitivity loss, and subjective clinical outcome after primary anterior cruciate ligament (ACL) reconstruction with either bone-patellar tendon-bone (BPTB) or quadriceps tendon-bone (QTB) autografts in a noninferiority study design. From 2005 to 2009, a total of 51 patients were included in the present study. Inclusion criteria were isolated ACL injuries in adults. Twenty-five patients were randomized to BPTB grafts and 26 to QTB grafts. An independent examiner performed follow-up evaluations 1 and 2 years postoperatively. Anteroposterior knee laxity was measured with a KT-1000 arthrometer (MEDmetric, San Diego, CA). Anterior knee pain was assessed clinically and by knee-walking ability. Knee Injury and Osteoarthritis Outcome Score (KOOS) and subjective International Knee Documentation Committee (IKDC) score were used for patient-evaluated outcome. Anterior knee laxity was equal between the 2 groups with KT-1000 values of 1.1 ± 1.4 mm and 0.8 ± 1.7 mm standard deviation (SD) at follow-up in QTB and BPTB groups, respectively (P = .65), whereas positive pivot shift test results were seen less frequently (14% compared with 38%, respectively; P = .03). Anterior kneeling pain, evaluated by the knee walking ability test, was significantly less in the QTB group, with only 7% of patients grading knee walking as difficult or impossible compared with 34% in the BPTB group. At 1 and 2 years' follow-up, there was no difference between the 2 groups in subjective patient-evaluated outcome. The IKDC score was 75 ± 13 patients and 76 ± 16 SD at 1-year follow-up in QTB and BPTB groups, respectively (P = .78). At 2 years, 12 patients were lost to follow-up, resulting in 18 in the BPTB group and 21 in the QTB group. The use of the QTB graft results in less kneeling pain, graft site pain, and sensitivity loss than seen with BPTB grafts; however, similar anterior knee

  5. Skin flaps and grafts - self-care

    MedlinePlus

    ... Free flap - self-care; Skin autografting - self-care; Pressure ulcer skin flap self-care; Burns skin flap self- ... skin infection Surgery for skin cancer Venous ulcers , pressure ulcers , or diabetic ulcers that DO NOT heal After ...

  6. Graft Utilization in the Bridging Reconstruction of Irreparable Rotator Cuff Tears: A Systematic Review.

    PubMed

    Lewington, Matthew R; Ferguson, Devin P; Smith, T Duncan; Burks, Robert; Coady, Catherine; Wong, Ivan Ho-Bun

    2017-11-01

    Rotator cuff tears are one of the most common conditions affecting the shoulder. Because of the difficulty in managing massive rotator cuff tears and the inability of standard techniques to prevent arthropathy, surgeons have developed several novel techniques to improve outcomes and ideally alter the natural history. To systematically review the existing literature and analyze reported outcomes to evaluate the effectiveness of using a bridging graft reconstruction technique to treat large to massive irreparable rotator cuff tears. Systematic review. A systematic search of PubMed, EMBASE, CINAHL, and CENTRAL was employed with the key terms "tear," "allograft," and "rotator cuff." Eligibility was determined by a 3-phase screening process according to the outlined inclusion/exclusion criteria. Data in relation to the primary and secondary outcomes were summarized. The results were synthesized according to the origin of the graft and the level of evidence. Fifteen studies in total were included in this review: 2 comparative studies and 13 observational case series. Both the biceps tendon and the fascia lata autograft groups had significantly superior structural integrity rates on magnetic resonance imaging at 12-month minimum follow-up when compared with their partial primary repair counterparts (58% vs 26%, P = .036; 79% vs 58%, P < .05), respectively. Multiple noncomparative case series investigating allografts, xenografts, and synthetic materials for bridging reconstruction of large to massive rotator cuff tears demonstrated high structural healing rates (74%-90%, 73%-100%, and 60%-90%, respectively). Additionally, both comparative studies and case series demonstrated a general improvement of patients' functional outcome scores. Using a graft for an anatomic bridging rotator cuff repair results in improved function on objective testing and may be functionally better than nonanatomic or partial repair of large to massive rotator cuff tears. Allograft or xenograft

  7. Virtual evaluation of stent graft deployment: a validated modeling and simulation study.

    PubMed

    De Bock, S; Iannaccone, F; De Santis, G; De Beule, M; Van Loo, D; Devos, D; Vermassen, F; Segers, P; Verhegghe, B

    2012-09-01

    The presented study details the virtual deployment of a bifurcated stent graft (Medtronic Talent) in an Abdominal Aortic Aneurysm model, using the finite element method. The entire deployment procedure is modeled, with the stent graft being crimped and bent according to the vessel geometry, and subsequently released. The finite element results are validated in vitro with placement of the device in a silicone mock aneurysm, using high resolution CT scans to evaluate the result. The presented work confirms the capability of finite element computer simulations to predict the deformed configuration after endovascular aneurysm repair (EVAR). These simulations can be used to quantify mechanical parameters, such as neck dilations, radial forces and stresses in the device, that are difficult or impossible to obtain from medical imaging. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Clinical outcome of combined conjunctival autograft transplantation and amniotic membrane transplantation in pterygium surgery

    PubMed Central

    Malla, Tejsu; Jiang, Jing; Hu, Kai

    2018-01-01

    AIM To compare long-term outcome of primary and recurrent pterygium surgery with three different techniques: combined conjunctival autograft and overlay amniotic membrane transplantation (CAT with AMT), conjunctival autograft transplantation (CAT) alone and amniotic membrane transplantation (AMT) alone. METHODS In this retrospective study, 142 eyes of 142 pterygium patients (104 primary, 38 recurrent) who underwent CAT (group A), AMT (group B) or CAT with AMT (group C) respectively following surgical excision were reviewed and compared based on the recurrences and post-operative complications. RESULTS The number of recurrence post-surgery were 17 (9 from primary, 8 from recurrent; the same description below), 18 (10, 8) and 2 (1, 1) in groups A, B, and C respectively; dry eyes were 22 (16, 6), 27 (18, 9) and 7 (3, 4); conjunctival inflammations were 30 (17, 13), 27 (16, 11) and 11 (6, 5). Patients in group C (either primary or recurrent or both) mainly showed significantly better results than those in group A or B (P<0.05) regarding above-mentioned clinical effects. CONCLUSION Combined CAT and overly AMT have significantly lower rates of recurrence and postoperative complications for primary and recurrent pterygium surgery than CAT or AMT alone. PMID:29600172

  9. Fabrication of Custom-Shaped Grafts for Cartilage Regeneration

    PubMed Central

    Koo, Seungbum; Hargreaves, Brian A.; Gold, Garry E.; Dragoo, Jason L.

    2011-01-01

    Transplantation of engineered cartilage grafts is a promising method to treat diseased articular cartilage. The interfacial areas between the graft and the native tissues play an important role in the successful integration of the graft to adjacent native tissues. The purposes of the study were to create a custom shaped graft through 3D tissue shape reconstruction and rapid-prototype molding methods using MRI data, and to test the accuracy of the custom shaped graft against the original anatomical defect. An iatrogenic defect on the distal femur was identified with a 1.5 Tesla MRI and its shape was reconstructed into a three-dimensional (3D) computer model by processing the 3D MRI data. First, the accuracy of the MRI-derived 3D model was tested against a laser-scan based 3D model of the defect. A custom-shaped polyurethane graft was fabricated from the laser-scan based 3D model by creating custom molds through computer aided design and rapid-prototyping methods. The polyurethane tissue was laser-scanned again to calculate the accuracy of this process compared to the original defect. The volumes of the defect models from MRI and laser-scan were 537 mm3 and 405 mm3, respectively, implying that the MRI model was 33% larger than the laser-scan model. The average (±SD) distance deviation of the exterior surface of the MRI model from the laser-scan model was 0.4±0.4 mm. The custom-shaped tissue created from the molds was qualitatively very similar to the original shape of the defect. The volume of the custom-shaped cartilage tissue was 463 mm3 which was 15% larger than the laser-scan model. The average (±SD) distance deviation between the two models was 0.04±0.19 mm. Custom-shaped engineered grafts can be fabricated from standard sequence 3-D MRI data with the use of CAD and rapid-prototyping technology, which may help solve the interfacial problem between native cartilage and graft, if the grafts are custom made for the specific defect. The major source of error in

  10. Graft-Sparing Strategy for Thoracic Prosthetic Graft Infection.

    PubMed

    Uchino, Gaku; Yoshida, Takeshi; Kakii, Bunpachi; Furui, Masato

    2018-04-01

     Thoracic prosthetic graft infection is a rare but serious complication with no standard management. We reported our surgical experience on graft-sparing strategy for thoracic prosthetic graft infection.  This study included patients who underwent graft-sparing surgery for thoracic prosthetic graft infection at Matsubara Tokushukai Hospital in Japan from January 2000 to October 2017.  There were 17 patients included in the analyses, with a mean age at surgery of 71.0 ± 10.5 years; 11 were men. In-hospital mortality was observed in five patients (29.4%).  Graft-sparing surgery for thoracic prosthetic graft infection is an alternative option particularly for early graft infection after hemiarch replacement. Georg Thieme Verlag KG Stuttgart · New York.

  11. Validation of a fibula graft cutting guide for mandibular reconstruction: experiment with rapid prototyping mandible model.

    PubMed

    Lim, Se-Ho; Kim, Yeon-Ho; Kim, Moon-Key; Nam, Woong; Kang, Sang-Hoon

    2016-12-01

    We examined whether cutting a fibula graft with a surgical guide template, prepared with computer-aided design/computer-aided manufacturing (CAD/CAM), would improve the precision and accuracy of mandibular reconstruction. Thirty mandibular rapid prototype (RP) models were allocated to experimental (N = 15) and control (N = 15) groups. Thirty identical fibular RP models were assigned randomly, 15 to each group. For reference, we prepared a reconstructed mandibular RP model with a three-dimensional printer, based on surgical simulation. In the experimental group, a stereolithography (STL) surgical guide template, based on simulation, was used for cutting the fibula graft. In the control group, the fibula graft was cut manually, with reference to the reconstructed RP mandible model. The mandibular reconstructions were compared to the surgical simulation, and errors were calculated for both the STL surgical guide and the manual methods. The average differences in three-dimensional, minimum distances between the reconstruction and simulation were 9.87 ± 6.32 mm (mean ± SD) for the STL surgical guide method and 14.76 ± 10.34 mm (mean ± SD) for the manual method. The STL surgical guide method incurred less error than the manual method in mandibular reconstruction. A fibula cutting guide improved the precision of reconstructing the mandible with a fibula graft.

  12. FAS grafted superhydrophobic ceramic membrane

    NASA Astrophysics Data System (ADS)

    Lu, Jun; Yu, Yun; Zhou, Jianer; Song, Lixin; Hu, Xingfang; Larbot, Andre

    2009-08-01

    The hydrophobic properties of γ-Al 2O 3 membrane have been obtained by grafting fluoroalkylsilane (FAS) on the surface of the membrane. The following grafting parameters were studied: the eroding time of the original membrane, the grafting time, the concentration of FAS solution and the multiplicity of grafting. Hydrophobicity of the membranes was characterized by contact angle (CA) measurement. The thermogravimetric analysis (TGA) was used to investigate the weight loss process (25-800 °C) of the fluoroalkylsilane grafted on Al 2O 3 powders under different grafting conditions. The morphologies of the membranes modified under different parameters were examined by field emission scanning electron microscopy (FE-SEM) and the surface roughness (Ra) was measured using white light interferometers. A needle-like structure was observed on the membrane surface after modification, which causes the change of Ra. On the results above, we speculated a model to describe the reaction between FAS and γ-Al 2O 3 membrane surface as well as the formed surface morphology.

  13. Xenon Treatment Protects Against Cold Ischemia Associated Delayed Graft Function and Prolongs Graft Survival in Rats

    PubMed Central

    Zhao, H; Watts, H R; Chong, M; Huang, H; Tralau-Stewart, C; Maxwell, P H; Maze, M; George, A J T; Ma, D

    2013-01-01

    Prolonged hypothermic storage causes ischemia-reperfusion injury (IRI) in the renal graft, which is considered to contribute to the occurrence of the delayed graft function (DGF) and chronic graft failure. Strategies are required to protect the graft and to prolong renal graft survival. We demonstrated that xenon exposure to human proximal tubular cells (HK-2) led to activation of range of protective proteins. Xenon treatment prior to or after hypothermia–hypoxia challenge stabilized the HK-2 cellular structure, diminished cytoplasmic translocation of high-mobility group box (HMGB) 1 and suppressed NF-κB activation. In the syngeneic Lewis-to-Lewis rat model of kidney transplantation, xenon exposure to donors before graft retrieval or to recipients after engraftment decreased caspase-3 expression, localized HMGB-1 within nuclei and prevented TLR-4/NF-κB activation in tubular cells; serum pro-inflammatory cytokines IL-1β, IL-6 and TNF-α were reduced and renal function was preserved. Xenon treatment of graft donors or of recipients prolonged renal graft survival following IRI in both Lewis-to-Lewis isografts and Fischer-to-Lewis allografts. Xenon induced cell survival or graft functional recovery was abolished by HIF-1α siRNA. Our data suggest that xenon treatment attenuates DGF and enhances graft survival. This approach could be translated into clinical practice leading to a considerable improvement in long-term graft survival. PMID:23710625

  14. Scaffold Design for Bone Regeneration

    PubMed Central

    Polo-Corrales, Liliana; Latorre-Esteves, Magda; Ramirez-Vick, Jaime E.

    2014-01-01

    The use of bone grafts is the standard to treat skeletal fractures, or to replace and regenerate lost bone, as demonstrated by the large number of bone graft procedures performed worldwide. The most common of these is the autograft, however, its use can lead to complications such as pain, infection, scarring, blood loss, and donor-site morbidity. The alternative is allografts, but they lack the osteoactive capacity of autografts and carry the risk of carrying infectious agents or immune rejection. Other approaches, such as the bone graft substitutes, have focused on improving the efficacy of bone grafts or other scaffolds by incorporating bone progenitor cells and growth factors to stimulate cells. An ideal bone graft or scaffold should be made of biomaterials that imitate the structure and properties of natural bone ECM, include osteoprogenitor cells and provide all the necessary environmental cues found in natural bone. However, creating living tissue constructs that are structurally, functionally and mechanically comparable to the natural bone has been a challenge so far. This focus of this review is on the evolution of these scaffolds as bone graft substitutes in the process of recreating the bone tissue microenvironment, including biochemical and biophysical cues. PMID:24730250

  15. The Effect of Remnant Tissue Preservation in Anatomic Double-Bundle ACL Reconstruction on Knee Stability and Graft Maturation.

    PubMed

    Takahashi, Tsuneari; Kimura, Masashi; Hagiwara, Keiichi; Ohsawa, Takashi; Takeshita, Katsushi

    2018-06-13

    Several investigators have developed anterior cruciate ligament reconstructions (ACLR) with remnant tissue preservation (RTP) and have reported better clinical outcomes. However, the effects of RTP remain controversial. To date, no reports have compared both clinical and radiological outcomes of anatomic double-bundle ACLR using the hamstring tendon and outside-in technique with/without RTP. This article evaluates the effectiveness of RTP in ACLR on knee stability and graft maturation. In total, 75 patients with unilateral ACL injury who had undergone anatomic double-bundle ACLR using autografted hamstring tendon either with RTP (Group P, n  = 43) or without (Group N, n  = 32) were enrolled. Clinical scores, pre- and postoperative side-to-side differences (SSDs) obtained using Telos, radiological evaluations of the grafted tendon using the signal/noise quotient (SNQ) measured using magnetic resonance imaging, and arthroscopic evaluations of the grafted tendon were retrospectively compared between the groups. Postoperative SSDs were smaller in the Group P (0.78 ± 1.90 mm) than in the Group N (1.29 ± 2.18 mm); however, this difference was not significant. Comparing two subgroups of the Group P, the SSD was significantly smaller in those with sufficient remnant coverage (-0.56 ± 1.38 mm) than in those without (1.48 ± 1.77 mm) ( p  = 0.019), as well as in the Group N patients ( p  = 0.019). The degree of synovial coverage of the anteromedial ( p  = 0.0064) and posterolateral ( p  = 0.032) bundle grafted tendon at the time of second-look arthroscopy was significantly better in the Group P than in the Group N. SNQ values of ACL grafted tendon at proximal ( p  = 0.049), middle, and distal ( p  = 0.039) one-third in Group P were better than those in Group N. RTP may enhance synovial coverage and maturation of the grafted tendon. Sufficient remnant tissue coverage may contribute to better knee stability. This is a Level

  16. Allograft en bloc vagino-utero-ovarian avascular transplant versus autograft implantation in rats.

    PubMed

    Salehian, Mohammad-Taghi; Salehian, Arash; Mossaffa, Nariman; Hadian, Mehrnaz; Eghtesadi-Araghi, Payam

    2008-12-01

    The aim of this study was to compare the results of an allograft en bloc vagino-uteroovarian avascular transplant with those of autograft implantation in rats. Thirty-four inbred adult virgin female Albino rats (age range, 10 - 12 weeks) were divided into 2 groups: the control group (autograft, n=11) and the study group (en bloc vagino-utero-ovariectomy, n=23). In the study group, the uterus and adnexa and the ovaries of the donor rat were transplanted to the recipient animal. Twenty-five to 30 days after that procedure, all rats were killed, and the samples were assessed histopathologically. No immunosuppressive drugs were used. Ten rats died during the postoperative period. In 16 rats, the transplanted system had survived completely at the conclusion of the study. In each of the study groups, complete survival of the uterus and ovaries was noted in 8 rats (34.8% in the study group and 72.8% in the control group). In all rats except 1, histopathologic examination did not reveal any signs of the classic criteria for tissue rejection reaction. The lack of revascularization, nonspecific signs of inflammation, and the presence of large granular lymphocytes and natural killer cells were reported. Our data indicated that the outcome of both allograft and homograft avascular en bloc transplant of vagino-utero-ovariectomy in rats was successful, and that immunologic rejection did not seem to have an important role in those procedures.

  17. Patient-Specific, Multi-Scale Modeling of Neointimal Hyperplasia in Vein Grafts

    PubMed Central

    Donadoni, Francesca; Pichardo-Almarza, Cesar; Bartlett, Matthew; Dardik, Alan; Homer-Vanniasinkam, Shervanthi; Díaz-Zuccarini, Vanessa

    2017-01-01

    Neointimal hyperplasia is amongst the major causes of failure of bypass grafts. The disease progression varies from patient to patient due to a range of different factors. In this paper, a mathematical model will be used to understand neointimal hyperplasia in individual patients, combining information from biological experiments and patient-specific data to analyze some aspects of the disease, particularly with regard to mechanical stimuli due to shear stresses on the vessel wall. By combining a biochemical model of cell growth and a patient-specific computational fluid dynamics analysis of blood flow in the lumen, remodeling of the blood vessel is studied by means of a novel computational framework. The framework was used to analyze two vein graft bypasses from one patient: a femoro-popliteal and a femoro-distal bypass. The remodeling of the vessel wall and analysis of the flow for each case was then compared to clinical data and discussed as a potential tool for a better understanding of the disease. Simulation results from this first computational approach showed an overall agreement on the locations of hyperplasia in these patients and demonstrated the potential of using new integrative modeling tools to understand disease progression. PMID:28458640

  18. Tension degradation of anterior cruciate ligament grafts with dynamic flexion-extension loading: a biomechanical model in porcine knees.

    PubMed

    Dargel, Jens; Koebke, Jürgen; Brüggemann, Gert-Peter; Pennig, Dietmar; Schmidt-Wiethoff, Rüdiger

    2009-10-01

    This study investigates the influence of various femoral anterior cruciate ligament graft fixation methods on the amount of tension degradation and the initial fixation strength after cyclic flexion-extension loading in a porcine knee model. One hundred twenty porcine digital extensor tendons, used as 4-stranded free tendon grafts, were fixated within porcine femoral bone tunnels by use of extracortical button, cross-pin, or interference screw fixation. One hundred twenty porcine patellar tendon-bone grafts were fixated by use of cross-pin, interference screw, or press-fit fixation. Each femur-graft complex was submitted to cyclic flexion-extension loading for 1,000 cycles throughout different loading ranges, and the total loss of tension was determined. After cyclic testing, the grafts were loaded to failure, and the data were compared with a pullout series without cyclic loading. Tension degradation after 1,000 cycles of flexion-extension loading averaged 62.6% +/- 10.0% in free tendon grafts and 48.9% +/- 13.35% in patellar tendon-bone grafts. There was no influence of the loading range on the total amount of tension degradation. The total amount of tension degradation was the highest with interference screw fixation of free tendon and patellar tendon-bone grafts. Despite excessive loss of tension, the initial fixation strength of the femur-graft complex was not reduced. The method of femoral graft fixation significantly influenced tension degradation during dynamic flexion-extension loading. Femoral graft fixation methods that secure the graft close to the tunnel entrance and that displace the graft substance from the center of the bone tunnel show the largest amount of tension degradation during cyclic flexion-extension loading. The graft substance, not the fixation site, was the weakest link of the graft complex within this investigation. We believe that the graft fixation method should be considered when aiming to improve the precision of femoral graft

  19. Augmentation of Distal Biceps Repair With an Acellular Dermal Graft Restores Native Biomechanical Properties in a Tendon-Deficient Model.

    PubMed

    Conroy, Christine; Sethi, Paul; Macken, Craig; Wei, David; Kowalsky, Marc; Mirzayan, Raffy; Pauzenberger, Leo; Dyrna, Felix; Obopilwe, Elifho; Mazzocca, Augustus D

    2017-07-01

    The majority of distal biceps tendon injuries can be repaired in a single procedure. In contrast, complete chronic tears with severe tendon substance deficiency and retraction often require tendon graft augmentation. In cases with extensive partial tears of the distal biceps, a human dermal allograft may be used as an alternative to restore tendon thickness and biomechanical integrity. Dermal graft augmentation will improve load to failure compared with nonaugmented repair in a tendon-deficient model. Controlled laboratory study. Thirty-six matched specimens were organized into 1 of 4 groups: native tendon, native tendon with dermal graft augmentation, tendon with an attritional defect, and tendon with an attritional defect repaired with a graft. To mimic a chronic attritional biceps lesion, a defect was created by a complete tear, leaving 30% of the tendon's width intact. The repair technique in all groups consisted of cortical button and interference screw fixation. All specimens underwent cyclical loading for 3000 cycles and were then tested to failure; gap formation and peak load at failure were documented. The mean (±SD) load to failure (320.9 ± 49.1 N vs 348.8 ± 77.6 N, respectively; P = .38) and gap formation (displacement) (1.8 ± 1.4 mm vs 1.6 ± 1.1 mm, respectively; P = .38) did not differ between the native tendon groups with and without graft augmentation. In the tendon-deficient model, the mean load to failure was significantly improved with graft augmentation compared with no graft augmentation (282.1 ± 83.8 N vs 199.7 ± 45.5 N, respectively; P = .04), while the mean gap formation was significantly reduced (1.2 ± 1.0 mm vs 2.7 ± 1.4 mm, respectively; P = .04). The mean load to failure of the deficient tendon with graft augmentation (282.1 N) compared with the native tendon (348.8 N) was not significantly different ( P = .12). This indicates that the native tendon did not perform differently from the grafted deficient tendon. In a tendon

  20. The Effect of Graft Strength on Knee Laxity and Graft In-Situ Forces after Posterior Cruciate Ligament Reconstruction

    PubMed Central

    Lai, Yu-Shu; Chen, Wen-Chuan; Huang, Chang-Hung; Cheng, Cheng-Kung; Chan, Kam-Kong; Chang, Ting-Kuo

    2015-01-01

    Surgical reconstruction is generally recommended for posterior cruciate ligament (PCL) injuries; however, the use of grafts is still a controversial problem. In this study, a three-dimensional finite element model of the human tibiofemoral joint with articular cartilage layers, menisci, and four main ligaments was constructed to investigate the effects of graft strengths on knee kinematics and in-situ forces of PCL grafts. Nine different graft strengths with stiffness ranging from 0% (PCL rupture) to 200%, in increments of 25%, of an intact PCL’s strength were used to simulate the PCL reconstruction. A 100 N posterior tibial drawer load was applied to the knee joint at full extension. Results revealed that the maximum posterior translation of the PCL rupture model (0% stiffness) was 6.77 mm in the medial compartment, which resulted in tibial internal rotation of about 3.01°. After PCL reconstruction with any graft strength, the laxity of the medial tibial compartment was noticeably improved. Tibial translation and rotation were similar to the intact knee after PCL reconstruction with graft strengths ranging from 75% to 125% of an intact PCL. When the graft’s strength surpassed 150%, the medial tibia moved forward and external tibial rotation greatly increased. The in-situ forces generated in the PCL grafts ranged from 13.15 N to 75.82 N, depending on the stiffness. In conclusion, the strength of PCL grafts have has a noticeable effect on anterior-posterior translation of the medial tibial compartment and its in-situ force. Similar kinematic response may happen in the models when the PCL graft’s strength lies between 75% and 125% of an intact PCL. PMID:26001045

  1. Hemodynamic analysis of sequential graft from right coronary system to left coronary system.

    PubMed

    Wang, Wenxin; Mao, Boyan; Wang, Haoran; Geng, Xueying; Zhao, Xi; Zhang, Huixia; Xie, Jinsheng; Zhao, Zhou; Lian, Bo; Liu, Youjun

    2016-12-28

    Sequential and single grafting are two surgical procedures of coronary artery bypass grafting. However, it remains unclear if the sequential graft can be used between the right and left coronary artery system. The purpose of this paper is to clarify the possibility of right coronary artery system anastomosis to left coronary system. A patient-specific 3D model was first reconstructed based on coronary computed tomography angiography (CCTA) images. Two different grafts, the normal multi-graft (Model 1) and the novel multi-graft (Model 2), were then implemented on this patient-specific model using virtual surgery techniques. In Model 1, the single graft was anastomosed to right coronary artery (RCA) and the sequential graft was adopted to anastomose left anterior descending (LAD) and left circumflex artery (LCX). While in Model 2, the single graft was anastomosed to LAD and the sequential graft was adopted to anastomose RCA and LCX. A zero-dimensional/three-dimensional (0D/3D) coupling method was used to realize the multi-scale simulation of both the pre-operative and two post-operative models. Flow rates in the coronary artery and grafts were obtained. The hemodynamic parameters were also showed, including wall shear stress (WSS) and oscillatory shear index (OSI). The area of low WSS and OSI in Model 1 was much less than that in Model 2. Model 1 shows optimistic hemodynamic modifications which may enhance the long-term patency of grafts. The anterior segments of sequential graft have better long-term patency than the posterior segments. With rational spatial position of the heart vessels, the last anastomosis of sequential graft should be connected to the main branch.

  2. Graft function assessment in mouse models of single- and dual- kidney transplantation.

    PubMed

    Wang, Lei; Wang, Ximing; Jiang, Shan; Wei, Jin; Buggs, Jacentha; Fu, Liying; Zhang, Jie; Liu, Ruisheng

    2018-05-23

    Animal models of kidney transplantation (KTX) are widely used in studying immune response of hosts to implanted grafts. Additionally, KTX can be used in generating kidney-specific knockout animal models by transplantation of kidneys from donors with global knockout of a gene to wild type recipients or vise verse. Dual kidney transplantation (DKT) provides a more physiological environment for recipients than single kidney transplantation (SKT). However, DKT in mice is rare due to technical challenges. In this study, we successfully performed DKT in mice and compared the hemodynamic response and graft function with SKT. The surgical time, complications and survival rate of DKT were not significantly different from SKT, where survival rates were above 85%. Mice with DKT showed less injury and quicker recovery with lower plasma creatinine (Pcr) and higher GFR than SKT mice (Pcr = 0.34 and 0.17 mg/dl in DKT vs. 0.50 and 0.36 mg/dl in SKT at 1 and 3 days, respectively; GFR = 215 and 131 µl/min for DKT and SKT, respectively). In addition, the DKT exhibited better renal functional reserve and long-term outcome of renal graft function than SKT based on the response to acute volume expansion. In conclusion, we have successfully generated a mouse DKT model. The hemodynamic responses of DKT better mimic physiological situations with less kidney injury and better recovery than SKT because of reduced confounding factors such as single nephron hyperfiltration. We anticipate DKT in mice will provide an additional tool for evaluation of renal significance in physiology and disease.

  3. Xenon treatment protects against cold ischemia associated delayed graft function and prolongs graft survival in rats.

    PubMed

    Zhao, H; Watts, H R; Chong, M; Huang, H; Tralau-Stewart, C; Maxwell, P H; Maze, M; George, A J T; Ma, D

    2013-08-01

    Prolonged hypothermic storage causes ischemia-reperfusion injury (IRI) in the renal graft, which is considered to contribute to the occurrence of the delayed graft function (DGF) and chronic graft failure. Strategies are required to protect the graft and to prolong renal graft survival. We demonstrated that xenon exposure to human proximal tubular cells (HK-2) led to activation of range of protective proteins. Xenon treatment prior to or after hypothermia-hypoxia challenge stabilized the HK-2 cellular structure, diminished cytoplasmic translocation of high-mobility group box (HMGB) 1 and suppressed NF-κB activation. In the syngeneic Lewis-to-Lewis rat model of kidney transplantation, xenon exposure to donors before graft retrieval or to recipients after engraftment decreased caspase-3 expression, localized HMGB-1 within nuclei and prevented TLR-4/NF-κB activation in tubular cells; serum pro-inflammatory cytokines IL-1β, IL-6 and TNF-α were reduced and renal function was preserved. Xenon treatment of graft donors or of recipients prolonged renal graft survival following IRI in both Lewis-to-Lewis isografts and Fischer-to-Lewis allografts. Xenon induced cell survival or graft functional recovery was abolished by HIF-1α siRNA. Our data suggest that xenon treatment attenuates DGF and enhances graft survival. This approach could be translated into clinical practice leading to a considerable improvement in long-term graft survival. © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

  4. A Review on Biomechanics of Anterior Cruciate Ligament and Materials for Reconstruction

    PubMed Central

    Marieswaran, M.; Jain, Ishita; Garg, Bhavuk; Sharma, Vijay

    2018-01-01

    The anterior cruciate ligament is one of the six ligaments in the human knee joint that provides stability during articulations. It is relatively prone to acute and chronic injuries as compared to other ligaments. Repair and self-healing of an injured anterior cruciate ligament are time-consuming processes. For personnel resuming an active sports life, surgical repair or replacement is essential. Untreated anterior cruciate ligament tear results frequently in osteoarthritis. Therefore, understanding of the biomechanics of injury and properties of the native ligament is crucial. An abridged summary of the prominent literature with a focus on key topics on kinematics and kinetics of the knee joint and various loads acting on the anterior cruciate ligament as a function of flexion angle is presented here with an emphasis on the gaps. Briefly, we also review mechanical characterization composition and anatomy of the anterior cruciate ligament as well as graft materials used for replacement/reconstruction surgeries. The key conclusions of this review are as follows: (a) the highest shear forces on the anterior cruciate ligament occur during hyperextension/low flexion angles of the knee joint; (b) the characterization of the anterior cruciate ligament at variable strain rates is critical to model a viscoelastic behavior; however, studies on human anterior cruciate ligament on variable strain rates are yet to be reported; (c) a significant disparity on maximum stress/strain pattern of the anterior cruciate ligament was observed in the earlier works; (d) nearly all synthetic grafts have been recalled from the market; and (e) bridge-enhanced repair developed by Murray is a promising technique for anterior cruciate ligament reconstruction, currently in clinical trials. It is important to note that full extension of the knee is not feasible in the case of most animals and hence the loading pattern of human ACL is different from animal models. Many of the published reviews on

  5. Evolution of skin grafting for treatment of burns: Reverdin pinch grafting to Tanner mesh grafting and beyond.

    PubMed

    Singh, Mansher; Nuutila, Kristo; Collins, K C; Huang, Anne

    2017-09-01

    Skin grafting is the current standard care in the treatment of full thickness burns. It was first described around 1500 BC but the vast majority of advancements have been achieved over the past 200 years. An extensive literature review was conducted on Pubmed, Medline and Google Scholar researching the evolution of skin grafting techniques. The authors concentrated on the major landmarks of skin grafting and also provide an overview of ongoing research efforts in this field. The major innovations of skin grafting include Reverdin pinch grafting, Ollier grafting, Thiersch grafting, Wolfe grafting, Padgett dermatome and modifications, Meek-wall microdermatome and Tanner mesh grafting. A brief description of the usage, advantages and limitations of each technique is included in the manuscript. Skin grafting technique have evolved significantly over past 200 years from Reverdin pinch grafting to modern day meshed skin grafts using powered dermatome. Increasing the expansion ratio and improving the cosmetic and functional outcome are the main focus of ongoing skin grafting research and emerging techniques (such as Integra ® , Recell ® , Xpansion ® ) are showing promise. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

  6. Effect of bursa Fabricius extracts on antibody production in bursectomized or bursal cell autografted chickens.

    PubMed Central

    Baba, T; Okuno, Y

    1976-01-01

    Restoration and enhancement of immune response against BSA antigen was achieved by 5-day consecutive doses of BF estract from 4-5-week-old chickens, in birds which had been surgically bursectomized or given BF-cell autografts at 17 days of age. A similar 5-day treatment with other tissue extract, i.e. liver, spleen, pancreas or intestine, or with LPS of E. coli, in contrast, failed to provide such restoration or enhancement. PMID:61937

  7. Skin graft

    MedlinePlus

    ... that need skin grafts to heal Venous ulcers, pressure ulcers , or diabetic ulcers that do not heal Very ... graft; Full thickness skin graft Patient Instructions Preventing pressure ulcers Surgical wound care - open Images Skin graft Skin ...

  8. Statistical Shape Modeling for Cavopulmonary Assist Device Development: Variability of Vascular Graft Geometry and Implications for Hemodynamics.

    PubMed

    Bruse, Jan L; Giusti, Giuliano; Baker, Catriona; Cervi, Elena; Hsia, Tain-Yen; Taylor, Andrew M; Schievano, Silvia

    2017-06-01

    Patients born with a single functional ventricle typically undergo three-staged surgical palliation in the first years of life, with the last stage realizing a cross-like total cavopulmonary connection (TCPC) of superior and inferior vena cavas (SVC and IVC) with both left and right pulmonary arteries, allowing all deoxygenated blood to flow passively back to the lungs (Fontan circulation). Even though within the past decades more patients survive into adulthood, the connection comes at the prize of deficiencies such as chronic systemic venous hypertension and low cardiac output, which ultimately may lead to Fontan failure. Many studies have suggested that the TCPC's inherent insufficiencies might be addressed by adding a cavopulmonary assist device (CPAD) to provide the necessary pressure boost. While many device concepts are being explored, few take into account the complex cardiac anatomy typically associated with TCPCs. In this study, we focus on the extra cardiac conduit vascular graft connecting IVC and pulmonary arteries as one possible landing zone for a CPAD and describe its geometric variability in a cohort of 18 patients that had their TCPC realized with a 20mm vascular graft. We report traditional morphometric parameters and apply statistical shape modeling to determine the main contributors of graft shape variability. Such information may prove useful when designing CPADs that are adapted to the challenging anatomical boundaries in Fontan patients. We further compute the anatomical mean 3D graft shape (template graft) as a representative of key shape features of our cohort and prove this template graft to be a significantly better approximation of population and individual patient's hemodynamics than a commonly used simplified tube geometry. We therefore conclude that statistical shape modeling results can provide better models of geometric and hemodynamic boundary conditions associated with complex cardiac anatomy, which in turn may impact on improved

  9. Muscle contributions to medial tibiofemoral compartment contact loading following ACL reconstruction using semitendinosus and gracilis tendon grafts.

    PubMed

    Konrath, Jason M; Saxby, David J; Killen, Bryce A; Pizzolato, Claudio; Vertullo, Christopher J; Barrett, Rod S; Lloyd, David G

    2017-01-01

    The muscle-tendon properties of the semitendinosus (ST) and gracilis (GR) are substantially altered following tendon harvest for the purpose of anterior cruciate ligament reconstruction (ACLR). This study adopted a musculoskeletal modelling approach to determine how the changes to the ST and GR muscle-tendon properties alter their contribution to medial compartment contact loading within the tibiofemoral joint in post ACLR patients, and the extent to which other muscles compensate under the same external loading conditions during walking, running and sidestep cutting. Motion capture and electromyography (EMG) data from 16 lower extremity muscles were acquired during walking, running and cutting in 25 participants that had undergone an ACLR using a quadruple (ST+GR) hamstring auto-graft. An EMG-driven musculoskeletal model was used to estimate the medial compartment contact loads during the stance phase of each gait task. An adjusted model was then created by altering muscle-tendon properties for the ST and GR to reflect their reported changes following ACLR. Parameters for the other muscles in the model were calibrated to match the experimental joint moments. The medial compartment contact loads for the standard and adjusted models were similar. The combined contributions of ST and GR to medial compartment contact load in the adjusted model were reduced by 26%, 17% and 17% during walking, running and cutting, respectively. These deficits were balanced by increases in the contribution made by the semimembranosus muscle of 33% and 22% during running and cutting, respectively. Alterations to the ST and GR muscle-tendon properties in ACLR patients resulted in reduced contribution to medial compartment contact loads during gait tasks, for which the semimembranosus muscle can compensate.

  10. Graft selection strategy in adult-to-adult living donor liver transplantation: When both hemiliver grafts meet volumetric criteria.

    PubMed

    Kurihara, Takeshi; Yoshizumi, Tomoharu; Yoshida, Yoshihiro; Ikegami, Toru; Itoh, Shinji; Harimoto, Norifumi; Ninomiya, Mizuki; Uchiyama, Hideaki; Okabe, Hirohisa; Kimura, Koichi; Kawanaka, Hirofumi; Shirabe, Ken; Maehara, Yoshihiko

    2016-07-01

    To ensure donor safety in living donor liver transplantation (LDLT), the left and caudate lobe (LL) is the preferred graft choice. However, patient prognosis may still be poor even if graft volume (GV) selection criteria are met. Our aim was to evaluate the effects of right lobe (RL) donation when the LL graft selection criteria are met. Consecutive donors (n = 135) with preoperative LL graft volumetric GV/standard liver volume (SLV) of ≥35% and RL remnant of ≥35% were retrospectively studied. Patients were divided into 2 groups: LL graft and RL graft. Recipient's body surface area (BSA), Model for End-Stage Liver Disease (MELD) score, and the donor's age were higher in the RL group. The donor's BSA and preoperative volumetric GV/SLV of the LL graft were smaller in the RL group. The predicted score (calculated using data for graft size, donor age, MELD score, and the presence of portosystemic shunt, which correlated well with graft function and with 6-month graft survival) of the RL group, was significantly lower if the LL graft were used, but using the actual RL graft improved the score equal to that of the LL group. Six-month and 12-month graft survival rates did not differ between the 2 groups. In patients with a poor prognosis, a larger RL graft improved the predicted score and survival was equal to that of patients who received LL grafts. In conclusion, graft selection by GV, donor age, and recipient MELD score improves outcomes in LDLT. Liver Transplantation 22 914-922 2016 AASLD. © 2016 American Association for the Study of Liver Diseases.

  11. Identification of subgroups by risk of graft failure after paediatric renal transplantation: application of survival tree models on the ESPN/ERA-EDTA Registry.

    PubMed

    Lofaro, Danilo; Jager, Kitty J; Abu-Hanna, Ameen; Groothoff, Jaap W; Arikoski, Pekka; Hoecker, Britta; Roussey-Kesler, Gwenaelle; Spasojević, Brankica; Verrina, Enrico; Schaefer, Franz; van Stralen, Karlijn J

    2016-02-01

    Identification of patient groups by risk of renal graft loss might be helpful for accurate patient counselling and clinical decision-making. Survival tree models are an alternative statistical approach to identify subgroups, offering cut-off points for covariates and an easy-to-interpret representation. Within the European Society of Pediatric Nephrology/European Renal Association-European Dialysis and Transplant Association (ESPN/ERA-EDTA) Registry data we identified paediatric patient groups with specific profiles for 5-year renal graft survival. Two analyses were performed, including (i) parameters known at time of transplantation and (ii) additional clinical measurements obtained early after transplantation. The identified subgroups were added as covariates in two survival models. The prognostic performance of the models was tested and compared with conventional Cox regression analyses. The first analysis included 5275 paediatric renal transplants. The best 5-year graft survival (90.4%) was found among patients who received a renal graft as a pre-emptive transplantation or after short-term dialysis (<45 days), whereas graft survival was poorest (51.7%) in adolescents transplanted after long-term dialysis (>2.2 years). The Cox model including both pre-transplant factors and tree subgroups had a significantly better predictive performance than conventional Cox regression (P < 0.001). In the analysis including clinical factors, graft survival ranged from 97.3% [younger patients with estimated glomerular filtration rate (eGFR) >30 mL/min/1.73 m(2) and dialysis <20 months] to 34.7% (adolescents with eGFR <60 mL/min/1.73 m(2) and dialysis >20 months). Also in this case combining tree findings and clinical factors improved the predictive performance as compared with conventional Cox model models (P < 0.0001). In conclusion, we demonstrated the tree model to be an accurate and attractive tool to predict graft failure for patients with specific characteristics. This may

  12. Interfascicular suture with nerve autografts for median, ulnar and radial nerve lesions.

    PubMed

    Pluchino, F; Luccarelli, G

    1981-05-01

    Interfascicular nerve suture with autografts is the operation of choice for repairing peripheral nerve injuries because it ensures more precise alignment of the fasciculi and so better chances of reinnervation of the sectioned nerve. The procedure as described by Millesi et al has been used at the Istituto Neurologico di Milano in 30 patients with traumatic lesions of the median, ulnar and radial nerves. All have been followed up for 2 to 7 years since operation. The results obtained are compared with those of other series obtained with interfascicular suture and with epineural suture. Microsurgery is essential. The best time to operate is discussed.

  13. Postoperative Complications of Dermis-Fat Autografts in the Anophthalmic Socket.

    PubMed

    Starks, Victoria; Freitag, Suzanne K

    2018-01-01

    Reconstruction of the anophthalmic socket allows the use of an ocular prosthesis and rehabilitation of facial appearance. Dermis-fat grafting is one option in volume augmentation of the anophthalmic socket and presents unique benefits, including increased surface area within the socket and the ability to grow with pediatric patients. Postoperative complications of this procedure are relatively common. Minor complications, such as graft hirsutism, keratinization, and conjunctival cysts or granulomas, are managed easily by observation or simple intervention. Major complications, such as graft atrophy, infection, or ulceration, may prevent good prosthesis fit and may require return to the operating room.

  14. Hybrid liposomes showing enhanced accumulation in tumors as theranostic agents in the orthotopic graft model mouse of colorectal cancer.

    PubMed

    Okumura, Masaki; Ichihara, Hideaki; Matsumoto, Yoko

    2018-11-01

    Hybrid liposomes (HLs) can be prepared by simply sonicating a mixture of vesicular and micellar molecules in a buffer solution. This study aimed to elucidate the therapeutic effects and ability of HLs to detect (diagnosis) cancer in an orthotopic graft mouse model of colorectal cancer with HCT116 cells for the use of HLs as theranostic agents. In the absence of a chemotherapeutic drug, HLs exhibited therapeutic effects by inhibiting the growth of HCT116 colorectal cancer cells in vitro, possibly through an increase in apoptosis. Intravenously administered HLs also caused a remarkable reduction in the relative cecum weight in an orthotopic graft mouse model of colorectal cancer. A decrease in tumor size in the cecal sections was confirmed by histological analysis using HE staining. TUNEL staining indicated an induction of apoptosis in HCT116 cells in the orthotopic graft mouse model of colorectal cancer. For the detection (diagnosis) of colorectal cancer by HLs, the accumulation of HLs encapsulating a fluorescent probe (ICG) was observed in HCT116 cells in the in vivo colorectal cancer model following intravenous administration. These data indicate that HLs can accumulate in tumor cells in the cecum of the orthotopic graft mouse model of colorectal cancer for a prolonged period of time, and inhibit the growth of HCT116 cells.

  15. Vein Graft Preservation Solutions, Patency, and Outcomes After Coronary Artery Bypass Graft Surgery

    PubMed Central

    Harskamp, Ralf E.; Alexander, John H.; Schulte, Phillip J.; Brophy, Colleen M.; Mack, Michael J.; Peterson, Eric D.; Williams, Judson B.; Gibson, C. Michael; Califf, Robert M.; Kouchoukos, Nicholas T.; Harrington, Robert A.; Ferguson, T. Bruce; Lopes, Renato D.

    2015-01-01

    IMPORTANCE In vitro and animal model data suggest that intraoperative preservation solutions may influence endothelial function and vein graft failure (VGF) after coronary artery bypass graft (CABG) surgery. Clinical studies to validate these findings are lacking. OBJECTIVE To evaluate the effect of vein graft preservation solutions on VGF and clinical outcomes in patients undergoing CABG surgery. DESIGN, SETTING, AND PARTICIPANTS Data from the Project of Ex-Vivo Vein Graft Engineering via Transfection IV (PREVENT IV) study, a phase 3, multicenter, randomized, double-blind, placebo-controlled trial that enrolled 3014 patients at 107 US sites from August 1, 2002, through October 22, 2003, were used. Eligibility criteria for the trial included CABG surgery for coronary artery disease with at least 2 planned vein grafts. INTERVENTIONS Preservation of vein grafts in saline, blood, or buffered saline solutions. MAIN OUTCOMES AND MEASURES One-year angiographic VGF and 5-year rates of death, myocardial infarction, and subsequent revascularization. RESULTS Most patients had grafts preserved in saline (1339 [44.4%]), followed by blood (971 [32.2%]) and buffered saline (507 [16.8%]). Baseline characteristics were similar among groups. One-year VGF rates were much lower in the buffered saline group than in the saline group (patient-level odds ratio [OR], 0.59 [95% CI, 0.45-0.78; P < .001]; graft-level OR, 0.63 [95% CI, 0.49-0.79; P < .001]) or the blood group (patient-level OR, 0.62 [95% CI, 0.46-0.83; P = .001]; graft-level OR, 0.63 [95% CI, 0.48-0.81; P < .001]). Use of buffered saline solution also tended to be associated with a lower 5-year risk for death, myocardial infarction, or subsequent revascularization compared with saline (hazard ratio, 0.81 [95% CI, 0.64-1.02; P = .08]) and blood (0.81 [0.63-1.03; P = .09]) solutions. CONCLUSIONS AND RELEVANCE Patients undergoing CABG whose vein grafts were preserved in a buffered saline solution had lower VGF rates and trends

  16. Hot callusing for propagation of American beech by grafting

    Treesearch

    David W. Carey; Mary E. Mason; Paul Bloese; Jennifer L. Koch

    2013-01-01

    To increase grafting success rate, a hot callus grafting system was designed and implemented as part of a multiagency collaborative project to manage beech bark disease (BBD) through the establishment of regional BBD-resistant grafted seed orchards. Five years of data from over 2000 hot callus graft attempts were analyzed using a logistic regression model to determine...

  17. Do Clinical Results and Return-to-Sport Rates After Ulnar Collateral Ligament Reconstruction Differ Based on Graft Choice and Surgical Technique?

    PubMed Central

    Erickson, Brandon J.; Cvetanovich, Gregory L.; Frank, Rachel M.; Bach, Bernard R.; Cohen, Mark S.; Bush-Joseph, Charles A.; Cole, Brian J.; Romeo, Anthony A.

    2016-01-01

    Background: Ulnar collateral ligament reconstruction (UCLR) has become a common procedure performed in overhead-throwing athletes of many athletic levels. Purpose/Hypothesis: The purpose of this study was to determine whether clinical outcomes and return-to-sport (RTS) rates differ among patients undergoing UCLR based on graft choice, surgical technique, athletic competition level, handedness, and treatment of the ulnar nerve. We hypothesized that no differences would exist in clinical outcomes or RTS rates between technique, graft choice, or other variables. Study Design: Cohort study; Level of evidence, 3. Methods: All patients who underwent UCLR from January 1, 2004 through December 31, 2014 at a single institution were identified. Charts were reviewed to determine patient age, sex, date of surgery, sport played, handedness, athletic level, surgical technique, graft type, and complications. Patients were contacted via telephone to obtain the RTS rate, Conway-Jobe score, Timmerman-Andrews score, and Kerlan-Jobe Orthopaedic Clinic (KJOC) Shoulder and Elbow score. Results: Eighty-five patients (mean age at surgery, 19.3 ± 4.7 years; 92% male; 78% right hand–dominant) underwent UCLR between 2004 and 2014 and were available for follow-up. Overall, 87% were baseball pitchers, 49.4% were college athletes, and 41.2% were high school athletes. No significant difference existed between the docking and double-docking techniques, graft choice, handedness, sex, activity level, and treatment of the ulnar nerve with regard to clinical outcomes, RTS, or subsequent surgeries (all P > .05). More complications were seen in the docking technique compared with the double-docking technique (P = .036). Hamstring autograft was used more commonly with the docking technique (P = .023) while allograft was used more commonly with the double-docking technique (P = .0006). Conclusion: Both the docking and double-docking techniques produce excellent clinical outcomes in patients undergoing

  18. Do Clinical Results and Return-to-Sport Rates After Ulnar Collateral Ligament Reconstruction Differ Based on Graft Choice and Surgical Technique?

    PubMed

    Erickson, Brandon J; Cvetanovich, Gregory L; Frank, Rachel M; Bach, Bernard R; Cohen, Mark S; Bush-Joseph, Charles A; Cole, Brian J; Romeo, Anthony A

    2016-11-01

    Ulnar collateral ligament reconstruction (UCLR) has become a common procedure performed in overhead-throwing athletes of many athletic levels. The purpose of this study was to determine whether clinical outcomes and return-to-sport (RTS) rates differ among patients undergoing UCLR based on graft choice, surgical technique, athletic competition level, handedness, and treatment of the ulnar nerve. We hypothesized that no differences would exist in clinical outcomes or RTS rates between technique, graft choice, or other variables. Cohort study; Level of evidence, 3. All patients who underwent UCLR from January 1, 2004 through December 31, 2014 at a single institution were identified. Charts were reviewed to determine patient age, sex, date of surgery, sport played, handedness, athletic level, surgical technique, graft type, and complications. Patients were contacted via telephone to obtain the RTS rate, Conway-Jobe score, Timmerman-Andrews score, and Kerlan-Jobe Orthopaedic Clinic (KJOC) Shoulder and Elbow score. Eighty-five patients (mean age at surgery, 19.3 ± 4.7 years; 92% male; 78% right hand-dominant) underwent UCLR between 2004 and 2014 and were available for follow-up. Overall, 87% were baseball pitchers, 49.4% were college athletes, and 41.2% were high school athletes. No significant difference existed between the docking and double-docking techniques, graft choice, handedness, sex, activity level, and treatment of the ulnar nerve with regard to clinical outcomes, RTS, or subsequent surgeries (all P > .05). More complications were seen in the docking technique compared with the double-docking technique ( P = .036). Hamstring autograft was used more commonly with the docking technique ( P = .023) while allograft was used more commonly with the double-docking technique ( P = .0006). Both the docking and double-docking techniques produce excellent clinical outcomes in patients undergoing UCLR. No difference in outcome scores was seen between surgical technique

  19. Electrostrictive Graft Elastomers

    NASA Technical Reports Server (NTRS)

    Su, Ji (Inventor); Harrison, Joycelyn S. (Inventor); St.Clair, Terry L. (Inventor)

    2003-01-01

    An electrostrictive graft elastomer has a backbone molecule which is a non-crystallizable, flexible macromolecular chain and a grafted polymer forming polar graft moieties with backbone molecules. The polar graft moieties have been rotated by an applied electric field, e.g., into substantial polar alignment. The rotation is sustained until the electric field is removed. In another embodiment, a process for producing strain in an elastomer includes: (a) providing a graft elastomer having a backbone molecule which is a non-crystallizable, flexible macromolecular chain and a grafted polymer forming polar graft moieties with backbone molecules; and (b) applying an electric field to the graft elastomer to rotate the polar graft moieties, e.g., into substantial polar alignment.

  20. Fabrication of custom-shaped grafts for cartilage regeneration.

    PubMed

    Koo, Seungbum; Hargreaves, Brian A; Gold, Garry E; Dragoo, Jason L

    2010-10-01

    to create a custom-shaped graft through 3D tissue shape reconstruction and rapid-prototype molding methods using MRI data, and to test the accuracy of the custom-shaped graft against the original anatomical defect. An iatrogenic defect on the distal femur was identified with a 1.5 Tesla MRI and its shape was reconstructed into a three-dimensional (3D) computer model by processing the 3D MRI data. First, the accuracy of the MRI-derived 3D model was tested against a laser-scan based 3D model of the defect. A custom-shaped polyurethane graft was fabricated from the laser-scan based 3D model by creating custom molds through computer aided design and rapid-prototyping methods. The polyurethane tissue was laser-scanned again to calculate the accuracy of this process compared to the original defect. The volumes of the defect models from MRI and laser-scan were 537 mm3 and 405 mm3, respectively, implying that the MRI model was 33% larger than the laser-scan model. The average (±SD) distance deviation of the exterior surface of the MRI model from the laser-scan model was 0.4 ± 0.4 mm. The custom-shaped tissue created from the molds was qualitatively very similar to the original shape of the defect. The volume of the custom-shaped cartilage tissue was 463 mm3 which was 15% larger than the laser-scan model. The average (±SD) distance deviation between the two models was 0.04 ± 0.19 mm. This investigation proves the concept that custom-shaped engineered grafts can be fabricated from standard sequence 3-D MRI data with the use of CAD and rapid-prototyping technology. The accuracy of this technology may help solve the interfacial problem between native cartilage and graft, if the grafts are custom made for the specific defect. The major source of error in fabricating a 3D custom-shaped cartilage graft appears to be the accuracy of a MRI data itself; however, the precision of the model is expected to increase by the utilization of advanced MR sequences with higher magnet

  1. Bone grafts.

    PubMed

    Hubble, Matthew J W

    2002-09-01

    Bone grafts are used in musculoskeletal surgery to restore structural integrity and enhance osteogenic potential. The demand for bone graft for skeletal reconstruction in bone tumor, revision arthroplasty, and trauma surgery, couple with recent advances in understanding and application of the biology of bone transplantation, has resulted in an exponential increase in the number of bone-grafting procedures performed over the last decade. It is estimated that 1.5 million bone-grafting procedures are currently performed worldwide each year, compared to a fraction of that number 20 years ago. Major developments also have resulted in the harvesting, storage, and use of bone grafts and production of graft derivatives, substitutes, and bone-inducing agents.

  2. Bone Remodeling in Acetabular Reconstruction Using a Kerboull-Type Reinforcement Device and Structural Bone-Grafting in Total Hip Arthroplasty.

    PubMed

    Oe, Kenichi; Iida, Hirokazu; Tsuda, Kohei; Nakamura, Tomohisa; Okamoto, Naofumi; Ueda, Yusuke

    2017-03-01

    The purpose of this study was to identify the long-term durability of the Kerboull-type reinforcement device (KT plate) in acetabular reconstruction for massive bone defects, assessing the remodeling of structural bone grafts. This study retrospectively evaluated 106 hips that underwent acetabular reconstruction using a KT plate between November 2000 and December 2010. Thirty-eight primary total hip arthoplasties (THAs) and 68 revised THAs were performed, and the mean duration of clinical follow-up was 8 years (5-14 years). Regarding reconstructing the acetabular bone defects, autografts were used in 37 hips, allografts in 68 hips, and A-W glass ceramics in 2 hips. One hip exhibited radiological migration and no revision for aseptic loosening. The mean Merle d'Aubigné Clinical Score improved from 7.5 points (4-12 points) preoperatively to 10.9 points (9-18 points) at the last follow-up. The Kaplan-Meier survival rate for radiological migration of primary and revised THAs at 10 years was 100% and 97% (95% confidence interval: 96%-100%), respectively. Bone remodeling was evaluated using the radiological demarcation at the bone-to-bone interface, and an improvement of 100% in primary THAs and 94% in revised THAs was observed. For massive bone defects, acetabular reconstruction using the KT plate with a structural bone grafting can yield successful results. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Postconditioning effects of argon or xenon on early graft function in a porcine model of kidney autotransplantation.

    PubMed

    De Deken, J; Rex, S; Lerut, E; Martinet, W; Monbaliu, D; Pirenne, J; Jochmans, I

    2018-07-01

    Ischaemia-reperfusion injury is inevitable during renal transplantation and can lead to delayed graft function and primary non-function. Preconditioning, reconditioning and postconditioning with argon and xenon protects against renal ischaemia-reperfusion injury in rodent models. The hypothesis that postconditioning with argon or xenon inhalation would improve graft function in a porcine renal autotransplant model was tested. Pigs (n = 6 per group) underwent left nephrectomy after 60 min of warm ischaemia (renal artery and vein clamping). The procured kidney was autotransplanted in a separate procedure after 18 h of cold storage, immediately after a right nephrectomy. Upon reperfusion, pigs were randomized to inhalation of control gas (70 per cent nitrogen and 30 per cent oxygen), argon (70 per cent and 30 per cent oxygen) or xenon (70 per cent and 30 per cent oxygen) for 2 h. The primary outcome parameter was peak plasma creatinine; secondary outcome parameters included further markers of graft function (creatinine course, urine output), graft injury (aspartate aminotransferase, heart-type fatty acid-binding protein, histology), apoptosis and autophagy (western blot, terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) staining), inflammatory mediators and markers of cell survival/growth (mRNA and tissue protein quantification), and animal survival. Results are presented as median (i.q.r.). ANOVA and Kruskal-Wallis tests were used where indicated. Peak plasma creatinine levels were similar between the groups: control 20·8 (16·4-23·1) mg/dl, argon 21·4 (17·1-24·9) mg/dl and xenon 19·4 (17·5-21·0) mg/dl (P = 0·607). Xenon was associated with an increase in autophagy and proapoptotic markers. Creatinine course, urine output, injury markers, histology, survival and inflammatory mediators were not affected by the intervention. Postconditioning with argon or xenon did not improve kidney graft function in this

  4. PRFM enhance wound healing process in skin graft.

    PubMed

    Reksodiputro, Mirta; Widodo, Dini; Bashiruddin, Jenny; Siregar, Nurjati; Malik, Safarina

    2014-12-01

    Facial plastic and reconstructive surgery often used skin graft on defects that cannot be covered primarily by a local flap. However, wound healing using skin graft is slow, most of the time the graft is contractured and the take of graft is not optimal. Platelet rich fibrin matrix (PRFM) is a new generation of concentrated platelets that produce natural fibrin and reported to speed up the healing process. Application of PRFM in the skin graft implants is expected to increase the survival of the graft. We used porcine as animal models to elucidate the effect of autologous PRFM on wound healing in full-thickness (FTSG) and split-thickness (STSG) skin grafts. Survival level of the skin graft was determined by using ImageJ software based on the formation of collagen type 1 and graft take. We observed that the use of PRFM in FTSG and STSG increased type 1 collagen formation. We also found that PRFM addition in STSG gave the best skin graft take. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  5. Magnesium inference screw supports early graft incorporation with inhibition of graft degradation in anterior cruciate ligament reconstruction

    PubMed Central

    Cheng, Pengfei; Han, Pei; Zhao, Changli; Zhang, Shaoxiang; Zhang, Xiaonong; Chai, Yimin

    2016-01-01

    Patients after anterior cruciate ligament (ACL) reconstruction surgery commonly encounters graft failure in the initial phase of rehabilitation. The inhibition of graft degradation is crucial for the successful reconstruction of the ACL. Here, we used biodegradable high-purity magnesium (HP Mg) screws in the rabbit model of ACL reconstruction with titanium (Ti) screws as a control and analyzed the graft degradation and screw corrosion using direct pull-out tests, microCT scanning, and histological and immunohistochemical staining. The most noteworthy finding was that tendon graft fixed by HP Mg screws exhibited biomechanical properties substantially superior to that by Ti screws and the relative area of collagen fiber at the tendon-bone interface was much larger in the Mg group, when severe graft degradation was identified in the histological analysis at 3 weeks. Semi-quantitative immunohistochemical results further elucidated that the MMP-13 expression significantly decreased surrounding HP Mg screws with relatively higher Collagen II expression. And HP Mg screws exhibited uniform corrosion behavior without displacement or loosening in the femoral tunnel. Therefore, our results demonstrated that Mg screw inhibited graft degradation and improved biomechanical properties of tendon graft during the early phase of graft healing and highlighted its potential in ACL reconstruction. PMID:27210585

  6. Magnesium inference screw supports early graft incorporation with inhibition of graft degradation in anterior cruciate ligament reconstruction

    NASA Astrophysics Data System (ADS)

    Cheng, Pengfei; Han, Pei; Zhao, Changli; Zhang, Shaoxiang; Zhang, Xiaonong; Chai, Yimin

    2016-05-01

    Patients after anterior cruciate ligament (ACL) reconstruction surgery commonly encounters graft failure in the initial phase of rehabilitation. The inhibition of graft degradation is crucial for the successful reconstruction of the ACL. Here, we used biodegradable high-purity magnesium (HP Mg) screws in the rabbit model of ACL reconstruction with titanium (Ti) screws as a control and analyzed the graft degradation and screw corrosion using direct pull-out tests, microCT scanning, and histological and immunohistochemical staining. The most noteworthy finding was that tendon graft fixed by HP Mg screws exhibited biomechanical properties substantially superior to that by Ti screws and the relative area of collagen fiber at the tendon-bone interface was much larger in the Mg group, when severe graft degradation was identified in the histological analysis at 3 weeks. Semi-quantitative immunohistochemical results further elucidated that the MMP-13 expression significantly decreased surrounding HP Mg screws with relatively higher Collagen II expression. And HP Mg screws exhibited uniform corrosion behavior without displacement or loosening in the femoral tunnel. Therefore, our results demonstrated that Mg screw inhibited graft degradation and improved biomechanical properties of tendon graft during the early phase of graft healing and highlighted its potential in ACL reconstruction.

  7. Management of facial burns with a collagen/glycosaminoglycan skin substitute-prospective experience with 12 consecutive patients with large, deep facial burns.

    PubMed

    Klein, Matthew B; Engrav, Loren H; Holmes, James H; Friedrich, Jeffrey B; Costa, Beth A; Honari, Shari; Gibran, Nicole S

    2005-05-01

    Management of deep facial burns remains one of the greatest challenges in burn care. We have developed a protocol over the past 20 years for management of facial burns that includes excision and coverage with thick autograft. However, the results were not perfect. Deformities of the eyelids, nose and mouth as well as the prominence of skin graft junctures demonstrated the need to explore novel approaches. Integra has been used with success in the management of burns of the trunk and extremities. The purpose of this study was to prospectively evaluate the aesthetic outcome of the use of Integra for deep facial burns. Twelve consecutive patients underwent excision of large, deep facial burns and placement of Integra. Integra provides excellent color and minimally visible skin graft junctures. The texture is good but not as supple as thick autograft. Integra is not well suited for use in the coverage of eyelid burns due to the need to wait 2 weeks for adequate vascularization. In summary, thick autograft remains the gold standard for deep facial burns. However, for patients with extensive burns and limited donor sites, Integra provides an acceptable alternative.

  8. Overall Graft Loss Versus Death-Censored Graft Loss: Unmasking the Magnitude of Racial Disparities in Outcomes Among US Kidney Transplant Recipients.

    PubMed

    Taber, David J; Gebregziabher, Mulugeta; Payne, Elizabeth H; Srinivas, Titte; Baliga, Prabhakar K; Egede, Leonard E

    2017-02-01

    Black kidney transplant recipients experience disproportionately high rates of graft loss. This disparity has persisted for 40 years, and improvements may be impeded based on the current public reporting of overall graft loss by US regulatory organizations for transplantation. Longitudinal cohort study of kidney transplant recipients using a data set created by linking Veterans Affairs and US Renal Data System information, including 4918 veterans transplanted between January 2001 and December 2007, with follow-up through December 2010. Multivariable analysis was conducted using 2-stage joint modeling of random and fixed effects of longitudinal data (linear mixed model) with time to event outcomes (Cox regression). Three thousand three hundred six non-Hispanic whites (67%) were compared with 1612 non-Hispanic black (33%) recipients with 6.0 ± 2.2 years of follow-up. In the unadjusted analysis, black recipients were significantly more likely to have overall graft loss (hazard ratio [HR], 1.19; 95% confidence interval [95% CI], 1.07-1.33), death-censored graft loss (HR, 1.67; 95% CI, 1.45-1.92), and lower mortality (HR, 0.83; 95% CI, 0.72-0.96). In fully adjusted models, only death-censored graft loss remained significant (HR, 1.38; 95% CI, 1.12-1.71; overall graft loss [HR, 1.08; 95% CI, 0.91-1.28]; mortality [HR, 0.84; 95% CI, 0.67-1.06]). A composite definition of graft loss reduced the magnitude of disparities in blacks by 22%. Non-Hispanic black kidney transplant recipients experience a substantial disparity in graft loss, but not mortality. This study of US data provides evidence to suggest that researchers should focus on using death-censored graft loss as the primary outcome of interest to facilitate a better understanding of racial disparities in kidney transplantation.

  9. Bilateral internal mammary artery grafting: in situ versus Y-graft. Similar 20-year outcome.

    PubMed

    Di Mauro, Michele; Iacò, Angela L; Allam, Ahmed; Awadi, Mohammed O; Osman, Ahmed A; Clemente, Daniela; Calafiore, Antonio M

    2016-10-01

    The aim of this study was to evaluate the 20-year clinical outcome of patients undergoing coronary artery bypass grafting with bilateral internal mammary arteries (BIMAs) using two different configurations, in situ versus Y-graft. From September 1991 to December 2002, 2150 patients with multivessel coronary artery disease underwent isolated myocardial revascularization with BIMA grafting. BIMA was used as an in situ or Y-configuration in 1332 and 818 cases, respectively. A propensity score model was applied to calculate a standardized difference of ≤10% between groups (BIMA in situ vs BIMA Y-graft), and a cohort of 1468 matched patients was identified (734 in each group). Death, non-fatal myocardial infarction and the need for repeat revascularization were defined as 'major adverse cardiac events'. Late mortality was 24.3% (n = 357) [BIMA in situ vs BIMA Y-graft: 26.9% (n = 197) vs 21.8% (n = 160)]; in 11.6% (n = 170) of cases death was due to cardiac causes [11.9% (n = 87) vs 11.3% (n = 83)]. The rate of major adverse cardiac events was 37.1% (n = 545) [40.8% (n = 299) vs 33.5% (n = 246)]. The 20-year survival was 59 ± 6% and the event-free survival was 45 ± 7%. The clinical outcome of BIMA grafting is independent of surgical configuration. Y-grafting increases the flexibility of BIMA grafting and should be taken into account when a surgical strategy for myocardial revascularization needs to be planned. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  10. Studies in fat grafting: Part III. Fat grafting irradiated tissue--improved skin quality and decreased fat graft retention.

    PubMed

    Garza, Rebecca M; Paik, Kevin J; Chung, Michael T; Duscher, Dominik; Gurtner, Geoffrey C; Longaker, Michael T; Wan, Derrick C

    2014-08-01

    Following radiation therapy, skin becomes fibrotic and can present a difficult problem for reconstructive surgeons. There is an increasing belief that fat grafting under irradiated skin can reverse the damage caused by radiation. The present study evaluated the effect of fat grafting on irradiated skin, along with fat graft quality and retention rates in irradiated tissue. Nine adult Crl:NU-Foxn1 CD-1 mice underwent 30-Gy external beam irradiation of the scalp. Four weeks after irradiation, scalp skin from irradiated and nonirradiated mice was harvested and compared histologically for dermal thickness, collagen content, and vascular density. Human fat grafts were then injected in the subcutaneous plane of the scalp. Skin assessment was performed in the irradiated group at 2 and 8 weeks after grafting, and fat graft retention was measured at baseline and every 2 weeks up to 8 weeks after grafting using micro-computed tomography. Finally, fat graft samples were explanted at 8 weeks, and quality scoring was performed. Fat grafting resulted in decreased dermal thickness, decreased collagen content, and increased vascular density in irradiated skin. Computed tomographic analysis revealed significantly decreased fat graft survival in the irradiated group compared with the nonirradiated group. Histologic scoring of explanted fat grafts demonstrated no difference in quality between the irradiated and nonirradiated groups. Fat grafting attenuates dermal collagen deposition and vessel depletion characteristic of radiation fibrosis. Although fat graft retention rates are significantly lower in irradiated than in nonirradiated tissue, the quality of retained fat between the groups is similar.

  11. Vascular replacement using a layered elastin-collagen vascular graft in a porcine model: one week patency versus one month occlusion

    PubMed Central

    Koens, M J W; Krasznai, A G; Hanssen, A E J; Hendriks, T; Praster, R; Daamen, W F; van der Vliet, J A; van Kuppevelt, T H

    2015-01-01

    abstract A persistent clinical demand exists for a suitable arterial prosthesis. In this study, a vascular conduit mimicking the native 3-layered artery, and constructed from the extracellular matrix proteins type I collagen and elastin, was evaluated for its performance as a blood vessel equivalent. A tubular 3-layered graft (elastin-collagen-collagen) was prepared using highly purified type I collagen fibrils and elastin fibers, resembling the 3-layered native blood vessel architecture. The vascular graft was crosslinked and heparinised (37 ± 4 μg heparin/mg graft), and evaluated as a vascular graft using a porcine bilateral iliac artery model. An intra-animal comparison with clinically-used heparinised ePTFE (Propaten®) was made. Analyses included biochemical characterization, duplex scanning, (immuno)histochemistry and scanning electron microscopy. The tubular graft was easy to handle with adequate suturability. Implantation resulted in pulsating grafts without leakage. One week after implantation, both ePTFE and the natural acellular graft had 100% patencies on duplex scanning. Grafts were partially endothelialised (Von Willebrand-positive endothelium with a laminin-positive basal membrane layer). After one month, layered thrombi were found in the natural (4/4) and ePTFE graft (1/4), resulting in occlusion which in case of the natural graft is likely due to the porosity of the inner elastin layer. In vivo application of a molecularly-defined tubular graft, based on nature's matrix proteins, for vascular surgery is feasible. PMID:26060888

  12. Treatment of gingival recession using free gingival graft with fibrin fibronectin sealing system: A novel approach

    PubMed Central

    Srinivas, B. V. V.; Rupa, N.; Halini Kumari, K. V.; Rajender, A.; Reddy, M. Narendra

    2015-01-01

    Periodontal plastic surgery is the branch of periodontology that is focused mainly on the correction or elimination of mucogingival problems associated with lack of attached gingiva, a shallow vestibule and aberrant frenum. Various mucogingival surgical procedures are used to halt the progression of the gingival recession and to correct poor esthetic appearance. Free gingival autograft is one of the most common techniques used for a gingival recession in areas of inadequate attached gingiva in the mandibular anterior region. Fibrin sealants are human plasma derivatives that mimic the final stages of blood coagulation, forming a fibrin clot. Fibrin Sealants enhances the overall outcome of surgical intervention because of their hemostatic, adhesive, and healing properties. These properties of fibrin sealants may reduce operating time, prevent complications, and enhance the overall outcome of many surgical interventions. Hence, this case report aims to investigate the clinical effectiveness of free gingival graft along with the commercially available fibrin-fibronectin sealing system (Tissucol®) in the treatment of Miller's class II gingival recession. PMID:26538956

  13. Hydrogen, a potential safeguard for graft-versus-host disease and graft ischemia-reperfusion injury?

    PubMed Central

    Yuan, Lijuan; Shen, Jianliang

    2016-01-01

    Post-transplant complications such as graft-versus-host disease and graft ischemia-reperfusion injury are crucial challenges in transplantation. Hydrogen can act as a potential antioxidant, playing a preventive role against post-transplant complications in animal models of multiple organ transplantation. Herein, the authors review the current literature regarding the effects of hydrogen on graft ischemia-reperfusion injury and graft-versus-host disease. Existing data on the effects of hydrogen on ischemia-reperfusion injury related to organ transplantation are specifically reviewed and coupled with further suggestions for future work. The reviewed studies showed that hydrogen (inhaled or dissolved in saline) improved the outcomes of organ transplantation by decreasing oxidative stress and inflammation at both the transplanted organ and the systemic levels. In conclusion, a substantial body of experimental evidence suggests that hydrogen can significantly alleviate transplantation-related ischemia-reperfusion injury and have a therapeutic effect on graft-versus-host disease, mainly via inhibition of inflammatory cytokine secretion and reduction of oxidative stress through several underlying mechanisms. Further animal experiments and preliminary human clinical trials will lay the foundation for hydrogen use as a drug in the clinic. PMID:27652837

  14. Influence of extracellular matrix proteins on human keratinocyte attachment, proliferation and transfer to a dermal wound model.

    PubMed

    Dawson, R A; Goberdhan, N J; Freedlander, E; MacNeil, S

    1996-03-01

    The aim of this study was to investigate whether prior culture of cells on ECM proteins might positively influence the performance of keratinocytes when cells are transferred to a dermal in vitro wound bed model. Keratinocytes were cultured using a method for producing cultured epithelial autografts for severely burned patients (essentially using Green's medium, a mitogen-rich medium containing fetal calf serum, cholera toxin, EGF, insulin, transferrin and triiodothyronine). Cells were cultured either on irradiated 3T3 fibroblasts (as in the standard Rheinwald and Green technique) or, alternatively, on collagen I, collagen IV, matrigel, RGD, vitronectin or fibronectin. Under these conditions matrigel, collagen I and IV enhanced initial attachment, RGD, vitronectin, fibronectin and irradiated 3T3 fibroblasts did not. Proliferation of cells was positively influenced by matrigel, collagen I and IV and irradiated 3T3 fibroblasts; of these, however, only matrigel and 3T3 fibroblasts had sustained significant effects on keratinocyte proliferation over 4 days. Cells on fibronectin showed significantly reduced proliferation. An acellular non-viable dermis was then used to mimic the homograft allodermis onto which cultured epithelial autograft sheets are grafted clinically and cells cultured on the various ECM proteins for 96 h were transferred to this in vitro wound model. None of the substrates enhanced keratinocyte performance on this model. It was concluded that under these conditions some ECM proteins can significantly affect keratinocyte attachment and, to a lesser extent, proliferation but that the culture of keratinocytes on these ECM proteins does not appear to confer any lasting benefit to the attachment of these keratinocytes to an in vitro wound-bed model.

  15. A simple in vitro model for investigating epithelial/mesenchymal interactions: keratinocyte inhibition of fibroblast proliferation and fibronectin synthesis.

    PubMed

    Harrison, Caroline A; Dalley, Andrew J; Mac Neil, Sheila

    2005-01-01

    Hypertrophic scarring and graft contracture are major causes of morbidity after burn injuries. It is well established that application of a split-thickness skin graft reduces scarring and contraction, and cultured epithelial autografts have a similar effect. To investigate the influence of keratinocytes on fibroblast proliferation and fibronectin synthesis, we used an in vitro separated co-culture model in which epithelial sheets were cultured above fibroblast monolayers without physical contact. We also investigated the response of fibroblasts to keratinocyte-conditioned medium (KCM) obtained from confluent and subconfluent keratinocyte monolayers. Both cultured epithelial sheets, composed of adherent fully confluent keratinocytes, and their conditioned medium, reduced fibroblast proliferation. However, KCM from subconfluent keratinocytes stimulated fibroblast proliferation at low concentrations while inhibiting it at higher concentrations, indicating that keratinocytes can produce both mitogenic and growth-inhibiting factors for fibroblasts. KCM, but not epithelial sheet co-culture, also inhibited fibroblast fibronectin synthesis. This indicates regulation of fibroblast phenotype by soluble factors released by the keratinocyte and also suggests that there is a dialogue between keratinocytes and fibroblasts with respect to fibronectin production. We conclude that this separated co-culture model is a simple way to study epithelial/mesenchymal communication particularly with respect to the role of the fibroblast in wound healing.

  16. Reconstruction of peripheral nerves using acellular nerve grafts with implanted cultured Schwann cells.

    PubMed

    Frerichs, Onno; Fansa, Hisham; Schicht, Christoph; Wolf, Gerald; Schneider, Wolfgang; Keilhoff, Gerburg

    2002-01-01

    The bridging of nerve gaps is still one of the major problems in peripheral nerve surgery. The present experiment describes our attempt to engineer different biologic nerve grafts in a rat sciatic nerve model: cultured isogenic Schwann cells were implanted into 2-cm autologous acellular nerve grafts or autologous predegenerated nerve grafts. Autologous nerve grafts and predegenerated or acellular nerve grafts without implanted Schwann cells served as controls. The regenerated nerves were assessed histologically and morphometrically after 6 weeks. Predegenerated grafts showed results superior in regard to axon count and histologic appearance in comparison to standard grafts and acellular grafts. The acellular nerve grafts showed the worst histologic picture, but axon counts were in the range of standard grafts. The implantation of Schwann cells did not yield significant improvements in any group. In conclusion, the status of activation of Schwann cells and the stadium of Wallerian degeneration in a nerve graft might be key factors for regeneration, rather than total number of Schwann cells. Predegenerated nerve grafts are therefore superior to standard grafts in the rat model. Acellular grafts are able to bridge nerve gaps of up to 2 cm in the rat model, but even the addition of cultivated Schwann cells did not lead to results as good as in the group with autologous nerve grafts. Copyright 2002 Wiley-Liss, Inc. MICROSURGERY 22:311-315 2002

  17. Acellular vascular matrix grafts from human placenta chorion: Impact of ECM preservation on graft characteristics, protein composition and in vivo performance.

    PubMed

    Schneider, Karl H; Enayati, Marjan; Grasl, Christian; Walter, Ingrid; Budinsky, Lubos; Zebic, Gabriel; Kaun, Christoph; Wagner, Anja; Kratochwill, Klaus; Redl, Heinz; Teuschl, Andreas H; Podesser, Bruno K; Bergmeister, Helga

    2018-05-29

    Small diameter vascular grafts from human placenta, decellularized with either Triton X-100 (Triton) or SDS and crosslinked with heparin were constructed and characterized. Graft biochemical properties, residual DNA, and protein composition were evaluated to compare the effect of the two detergents on graft matrix composition and structural alterations. Biocompatibility was tested in vitro by culturing the grafts with primary human macrophages and in vivo by subcutaneous implantation of graft conduits (n = 7 per group) into the flanks of nude rats. Subsequently, graft performance was evaluated using an aortic implantation model in Sprague Dawley rats (one month, n = 14). In situ graft imaging was performed using MRI angiography. Retrieved specimens were analyzed by electromyography, scanning electron microscopy, histology and immunohistochemistry to evaluate cell migration and the degree of functional tissue remodeling. Both decellularization methods resulted in grafts of excellent biocompatibility in vitro and in vivo, with low immunogenic potential. Proteomic data revealed removal of cytoplasmic proteins with relative enrichment of ECM proteins in decelluarized specimens of both groups. Noteworthy, LC-Mass Spectrometry analysis revealed that 16 proteins were exclusively preserved in Triton decellularized specimens in comparison to SDS-treated specimens. Aortic grafts showed high patency rates, no signs of thrombus formation, aneurysms or rupture. Conduits of both groups revealed tissue-specific cell migration indicative of functional remodeling. This study strongly suggests that decellularized allogenic grafts from the human placenta have the potential to be used as vascular replacement materials. Both detergents produced grafts with low residual immunogenicity and appropriate mechanical properties. Observed differences in graft characteristics due to preservation method had no impact on successful in vivo performance in the rodent model. Copyright

  18. A multilayered polyurethane foam technique for skin graft immobilization.

    PubMed

    Nakamura, Motoki; Ito, Erika; Kato, Hiroshi; Watanabe, Shoichi; Morita, Akimichi

    2012-02-01

    Several techniques are applicable for skin graft immobilization. Although the sponge dressing is a popular technique, pressure failure near the center of the graft is a weakness of the technique that can result in engraftment failure. To evaluate the efficacy of a new skin graft immobilization technique using multilayered polyurethane foam in vivo and in vitro. Twenty-six patients underwent a full-thickness skin graft. Multiple layers of a hydrocellular polyurethane foam dressing were used for skin graft immobilization. In addition, we created an in vitro skin graft model that allowed us to estimate immobilization pressure at the center and edges of skin grafts of various sizes. Overall mean graft survival was 88.9%. In the head and neck region (19 patients), mean graft survival was 93.6%. Based on the in vitro outcomes, this technique supplies effective pressure (<30 mmHg) to the center region of the skin graft. This multilayered polyurethane foam dressing is simple, safe, and effective for skin graft immobilization. © 2011 by the American Society for Dermatologic Surgery, Inc. Published by Wiley Periodicals, Inc.

  19. Grafting the alar rim: application as anatomical graft.

    PubMed

    Gruber, Ronald P; Fox, Paige; Peled, Anne; Belek, Kyle A

    2014-12-01

    Alar rim contour and alar rim grafts have become essential components of rhinoplasty. Ideally, grafts of the nose should be anatomical in shape. So doing might make grafts of the alar rim more robust. The authors considered doing that by applying the graft as a continuous extension of the lateral crus. Twelve patients (two men and 10 women) constituted the study group (seven primary and five secondary cases). Of those, there were five concave rims, two concave rims with rim retraction, two boxy tips, and three cephalically oriented lateral crura. Surgical technique included the following: (1) an open approach was used; (2) a marginal incision that ignored the caudal margin of the lateral crus (the incision went straight posteriorly to a point 5 to 6 mm from the rim margin) was used; (3) a triangular graft was made to cover the exposed vestibular skin; (4) it was secured end to end to the caudal border of the lateral crus; and (5) the poster end was allowed to sit in a small subcutaneous pocket. Follow-up was 11 to 19 months. All 12 patients exhibited good rims as judged by a blinded panel. Rim retraction was not fully corrected in one patient, but no further treatment was required. One patient did require a secondary small rim graft for residual rim concavity. The concept of grafting the alar rim is strongly supported by the authors' results. The modifications the authors applied by designing the graft to be anatomical in shape has been a technical help.

  20. Sustained Thromboresistant Bioactivity with Reduced Intimal Hyperplasia of Heparin-Bonded Polytetrafluoroethylene Propaten Graft in a Chronic Canine Femoral Artery Bypass Model.

    PubMed

    Freeman, John; Chen, Aaron; Weinberg, Roy J; Okada, Tamuru; Chen, Changyi; Lin, Peter H

    2018-05-01

    Bypass graft thrombosis remains a significant mode of failure in prosthetic graft revascularization. The purpose of this investigation was to evaluate the long-term thromboresistant effect of heparin-bonded expanded polytetrafluoroethylene (ePTFE) graft using Carmeda BioActive Surface technology in a canine model. Bilateral femorofemoral artery bypass grafts with ePTFE grafts were performed in 25 adult grayhound dogs. In each animal, a heparin-bonded ePTFE graft (Propaten, WL Gore) was placed on one side, whereas a control nonheparin graft was placed on the contralateral side. The graft patency was assessed at 1, 6, 12, 18, and 24 months (n = 5 per group) following the bypass. Heparin bioactivity of the graft material was analyzed. The effect of intimal hyperplasia was also assessed. All bypass grafts were patent at 1 month. Significantly greater patency rates were noted in the Propaten group compared to the control group at 12, 18, and 24 months, which were 84%, 80%, and 80% vs. 55%, 35%, and 20%, respectively (P < 0.02). There was a significant reduction in the anastomotic neointimal area and neointimal cell proliferation in Propaten grafts compared with control grafts at all groups between 6 and 24 months (P < 0.05). Heparin bioactivity as measured by antithrombin binding assay was demonstrated in the Propaten graft between 1 and 24 months. Mean heparin activities on Propaten grafts ranged from 26.3 ± 6.4 pmol/cm 2 to 18.4 ± 8.7 pmol/cm 2 between 1 and 24 months, which were significantly greater than the control group (P < 0.001). Differences between mean heparin activities of explanted Propaten graft samples at the various time points were nonsignificant (P > 0.05). Heparin-bonded ePTFE graft provides a thromboresistant surface and reduced anastomotic intimal hyperplasia at 2 years. The stable heparin bioactivity of the Propaten graft confers an advantage in long-term graft patency. Copyright © 2017 The Author(s). Published by Elsevier Inc

  1. Successful correction of tibial bone deformity through multiple surgical procedures, liquid nitrogen-pretreated bone tumor autograft, three-dimensional external fixation, and internal fixation in a patient with primary osteosarcoma: a case report.

    PubMed

    Takeuchi, Akihiko; Yamamoto, Norio; Shirai, Toshiharu; Nishida, Hideji; Hayashi, Katsuhiro; Watanabe, Koji; Miwa, Shinji; Tsuchiya, Hiroyuki

    2015-12-07

    In a previous report, we described a method of reconstruction using tumor-bearing autograft treated by liquid nitrogen for malignant bone tumor. Here we present the first case of bone deformity correction following a tumor-bearing frozen autograft via three-dimensional computerized reconstruction after multiple surgeries. A 16-year-old female student presented with pain in the left lower leg and was diagnosed with a low-grade central tibial osteosarcoma. Surgical bone reconstruction was performed using a tumor-bearing frozen autograft. Bone union was achieved at 7 months after the first surgical procedure. However, local tumor recurrence and lung metastases occurred 2 years later, at which time a second surgical procedure was performed. Five years later, the patient developed a 19° varus deformity and underwent a third surgical procedure, during which an osteotomy was performed using the Taylor Spatial Frame three-dimensional external fixation technique. A fourth corrective surgical procedure was performed in which internal fixation was achieved with a locking plate. Two years later, and 10 years after the initial diagnosis of tibial osteosarcoma, the bone deformity was completely corrected, and the patient's limb function was good. We present the first report in which a bone deformity due to a primary osteosarcoma was corrected using a tumor-bearing frozen autograft, followed by multiple corrective surgical procedures that included osteotomy, three-dimensional external fixation, and internal fixation.

  2. Effect of graft shape in lateral column lengthening on tarsal bone position and subtalar and talonavicular contact pressure in a cadaveric flatfoot model.

    PubMed

    Campbell, Sean T; Reese, Keri A; Ross, Steven D; McGarry, Michelle H; Leba, Thu-Ba; Lee, Thay Q

    2014-11-01

    Lateral column lengthening (LCL) has been used for correction of flatfoot deformity. The purpose of this study was to determine the effect of LCL graft shape on tarsal bone position and talonavicular and subtalar joint pressure. A flatfoot model was created in 6 cadaveric specimens. Corrective LCL was performed using a rectangular graft or a trapezoidal graft with the broad surface oriented dorsally, laterally, or plantarly. Bony surface markers were digitized to calculate angular parameters used in the evaluation of flatfoot deformity. Contact pressure and area in the subtalar and talonavicular joints were also recorded. All measurements were carried out under multiple axial loads in the intact and flatfoot conditions, and following LCL with each graft shape. Flatfoot creation resulted in significant changes in arch collapse and forefoot abduction. LCL with a rectangular graft best corrected these parameters, while a laterally oriented trapezoidal graft provided some correction. Talonavicular contact pressure was unchanged after flatfoot creation, and was significantly less than intact after LCL. Subtalar contact pressure decreased in some conditions after flatfoot creation, and decreased further after LCL. LCL with a rectangular graft best restored tarsal bone orientation in a cadaveric flatfoot model. The decreases in talonavicular pressure likely represent redistribution of force from the medial to lateral foot. When performing LCL for flatfoot deformity, increased bone graft volume medially better restores tarsal bone position. One way of achieving this is through the use of a rectangular graft as opposed to a trapezoidal graft. © The Author(s) 2014.

  3. Multiscale modeling and simulation of blood flow in coronary artery bypass graft surgeries

    NASA Astrophysics Data System (ADS)

    Sankaran, Sethuraman; Esmaily Moghadam, Mahdi; Kahn, Andy; Marsden, Alison

    2011-11-01

    We present a computational framework for modeling and simulation of blood flow in patients who undergo coronary artery bypass graft (CABG) surgeries. We evaluate the influence of shape on the homeostatic state, cardiac output, and other quantities of interest. We present a case study on a patient with multiple CABG. We build a patient-specific model of the blood vessels comprised of the aorta, vessels branching from the top of the aorta (brachiocephalic artery and carotids) and the coronary arteries, in addition to bypass grafts. The rest of the circulatory system is modeled using lumped parameter 0D models comprised of resistances, compliances, inertances and elastance. An algorithm is presented that computes these parameters automatically given constraints on the flow. A Finite element framework is used to compute blood flow and pressure in the 3D model to which the 0D code is coupled at the model inlets and outlets. An adaptive closed loop BC is used to capture the coupling of the various outlets of the model with inlets, and is compared with a model with fixed inlet BC. We compare and contrast the pressure, flowrate, coronary perfusion, and PV curves obtained in the different cases. Further, we compare and contrast quantities of interest such as wall shear stress, wall shear stress gradients and oscillatory shear index for different surgical geometries and discuss implications of patient-specific optimization. I would like to acknowlege AHA for funding this work.

  4. The study of the use of a latex biomembrane and conjunctival autograft in rabbit conjunctiva wound healing.

    PubMed

    Pinho, Erika Christina Canarim Martha de; Chahud, Fernando; Lachat, João-José; Coutinho-Netto, Joaquim José; Sousa, Sidney Julio Faria E

    2018-04-01

    RESUMO Objetivo: Estudar o uso da biomembrana de látex e o transplante conjuntival autólogo na cicatrização conjuntival em coelhos. Métodos: Em nove coelhos albinos, neo-zelandeses, machos foram removidas áreas retangulares idênticas, do quadrante supero nasal, adjacente ao limbo, de ambos os olhos. As áreas desnudas da camada esclerótica nos olhos direitos foram recobertas com biomembrana de látex e a dos olhos esquerdos com enxerto conjuntival autólogo. Os animais foram sacrificados em grupos de três, aos 7, 14 e 21 dias após a cirurgia. Os tecidos do local cirúrgico, incluindo a córnea, foram fixados em formaldeído, antes de serem processados em parafina e corados com hematoxilina e eosina. A natureza e a intensidade da resposta inflamatória e o padrão de epitelização da superfície conjuntival foram avaliados sob microscopia óptica, em seções histológicas longitudinais, passando pelo centro dos espécimes anatômicos. Resultados: Até o décimo quarto dia pós-operatório, o grupo que recebeu a biomembrana apresentou reação inflamatória mais intensa do que o grupo com auto enxerto conjuntival. Aos 14 dias, os olhos com biomembrana apresentavam-se menos inflamados e com estroma mais espesso do que aos 7 dias. Aos 21 dias, a reparação conjuntival de ambos os grupos apresentavam características semelhantes. Conclusão: Apesar de apresentar uma cicatrização mais lenta, a biomembrana de látex se mostrou tão eficaz quanto o auto enxerto conjuntival na reconstrução da superfície ocular após três semanas de cicatrização pós-operatória. Devido as suas baixas toxicidade e alergenicidade, este material parece ser uma opção terapêutica promissora na reconstrução da conjuntiva.ABSTRACT Purpose: To study a latex biomembrane and conjunctival autograft with regard to the promotion of conjunctival healing in rabbits. The study included nine male albino rabbits. In these rabbits, a rectangular area of the conjunctiva was surgically

  5. Feasibility Study of a Novel Thoraco-abdominal Aortic Hybrid Device (SPIDER-graft) in a Translational Pig Model.

    PubMed

    Debus, Eike S; Kölbel, Tilo; Duprée, Anna; Daum, Günter; Sandhu, Harleen K; Manzoni, Daniel; Wipper, Sabine H

    2018-02-01

    The hybrid SPIDER-graft consists of a proximal descending aortic stent graft and a conventional six branched Dacron graft for open abdominal aortic repair. Technical feasibility with regard to avoiding thoracotomy and extracorporeal circulation (ECC) during thoraco-abdominal aortic hybrid repair and peri-procedural safety of this novel device are unknown. This was a feasibility and safety study in domestic pigs (75-85 kg). The abdominal aorta including iliac bifurcation, left renal artery, and visceral arteries were exposed via retroperitoneal access. The right iliac branch was first temporarily anastomosed end to side to the distal aorta via partial clamping. During inflow reduction and infra-coeliac cross-clamping, the coeliac trunk (CT) was divided and the proximal stent graft portion of the SPIDER-graft was deployed into the descending aorta via the CT ostium. Retrograde visceral and antegrade aorto-iliac blood flow was maintained via the iliac side branch. The visceral, renal, and iliac arteries were sequentially anastomosed, finally replacing the first iliac end to side anastomosis. Technical success, blood flow, periods of ischaemia, and peri-procedural complications were evaluated after intra-operative completion angiography and post-operative computed tomography angiography. Six animals underwent successful thoracic stent graft deployment and distal open reconstruction without peri-operative death. The median thoracic graft implantation time was 4.5 min, and the median ischaemia times before reperfusion were 10 min for the CT, 8 min for the superior mesenteric artery, 13 min for the right renal artery, and 22 min for the left renal artery. Angiography demonstrated appropriate graft implantation and blood flow measurements confirmed sufficient blood flow through all side branches. In this translational pig model, thoraco-abdominal hybrid repair using the novel SPIDER-graft was successful in avoiding thoracotomy and ECC. Technical feasibility and

  6. Functional Performance Testing After Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Abrams, Geoffrey D.; Harris, Joshua D.; Gupta, Anil K.; McCormick, Frank M.; Bush-Joseph, Charles A.; Verma, Nikhil N.; Cole, Brian J.; Bach, Bernard R.

    2014-01-01

    Background: When to allow an athlete to return to unrestricted sporting activity after anterior cruciate ligament (ACL) reconstruction remains controversial. Purpose: To report the results of functional performance testing reported in the literature for individuals at differing time points following ACL reconstruction and to examine differences between graft types. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review of Medline, Scopus, and Cochrane Central Register of Controlled Trials was performed using PRISMA guidelines. Inclusion criteria were English-language studies that examined any functional rehabilitation test from 6 months to 2 years following ACL reconstruction. All patient-, limb-, and knee-specific demographics were extracted from included investigations. All functional rehabilitation tests were analyzed and compared when applicable. Results: The search term returned a total of 890 potential studies, with 88 meeting inclusion and exclusion criteria. A total of 4927 patients were included, of which 66% were male. The mean patient age was 26.5 ± 3.4 years. The predominant graft choices for reconstruction were bone–patellar tendon–bone (BPTB) autograft (59.8%) and hamstring autograft (37.9%). The most commonly reported functional tests were the hop tests. The results of these functional tests, as reported in the Limb Symmetry Index (LSI), improved with increasing time, with nearly all results greater than 90% at 1 year following primary ACL reconstruction. At 6 months postoperatively, a number of isokinetic strength measurements failed to reach 80% LSI, most commonly isokinetic knee extension testing in both BPTB and hamstring autograft groups. The knee flexion strength deficit was significantly less in the BPTB autograft group as compared with those having hamstring autograft at 1 year postoperatively, while no significant differences were found in isokinetic extension strength between the 2 groups. Conclusion: Hop

  7. Evaluation of Topical Lignocaine Jelly 2% for Recurrent Pterygium Surgery with Glue-free Autologous Conjunctival Graft

    PubMed Central

    Joshi, Rajesh Subhash

    2017-01-01

    AIM: This study aims to evaluate the efficacy of lignocaine 2% jelly as a topical anesthesia in recurrent pterygium surgery with glue-free conjunctival limbal autograft. MATERIALS AND METHODS: A prospective, nonrandomized, observational study, comprising of 51 patients (51 eyes) having recurrent pterygium, was conducted at a tertiary eye care center in central India. Pterygium excision with glue-free autologous conjunctival grafting was done under 2% lignocaine jelly. The visual analog scale was utilized to record the intra- and post-operative pain score. Patient comfort, intraoperative painful sensations perceived by the patient, supplemental anesthesia, complications, and surgeon discomfort were noted. Anesthetist also noted vital parameters and any intravenous drugs required. RESULTS: No difference in intra- and post-operative pain score (P = 0.24) was observed in the patients. Zero score, i.e. no pain was noticed in 30 patients (58.8%) patients. The average surgical time was 29.20 min (+1.11). The average surgeon discomfort score was 0.18 + 0.51. Inadvertent eye movement was seen in 3 patients (5.9%). Lid squeeze was noted in 45 patients (88.2%) during placement of lid speculum. Forty-eight patients (94.1%) gave preference to the topical anesthesia of 2% lignocaine jelly compared to the previous mode of anesthesia. CONCLUSION: Pterygium surgery with glue-free autogenous conjunctival grafting can be performed successfully by preoperative local application of 2% lignocaine jelly. The ease of application, lack of toxicity and sufficient effect to complete the surgery make it an efficient alternative to injectable anesthetics. PMID:29279652

  8. Detection of airway ischaemic damage after lung transplantation by using autofluorescence imaging bronchoscopy.

    PubMed

    Iga, Norichika; Oto, Takahiro; Okada, Masanori; Harada, Masaaki; Nishikawa, Hitoshi; Miyoshi, Kentaroh; Otani, Shinji; Sugimoto, Seiichiro; Yamane, Masaomi; Toyooka, Shinichi; Miyoshi, Shinichiro

    2014-03-01

    Airway complications related to ischaemia are a major cause of morbidity after lung transplantation. Early detection of airway ischaemia and optimal management of the anastomotic site could reduce the risk of airway complications. Autofluorescence imaging (AFI) bronchoscopy has been increasingly recognized as an effective technique for detecting abnormal mucosal thickening. The aim of this study was to investigate whether AFI bronchoscopy can facilitate the detection of airway ischaemic damage in lung transplant patients. Twenty Landrace pigs were used to create a tracheal autotransplantation model. A four-ring length of trachea was excised and implanted orthotopically. The tracheal autograft was observed on postoperative days 0, 2, 4 and 7 with AFI bronchoscopy. The extent and origin of graft autofluorescence were examined using histology and measured according to fluorescence intensity. The lesions on the tracheal autografts appeared as bright green fluorescence on AFI bronchoscopy. On confocal fluorescence microscopy, high-intensity green fluorescence was observed in the elastin fibre layer of the submucosa. The fluorescence intensity of elastin was significantly higher in the graft showing fluorescence than the graft that did not show fluorescence and that at the control site. Bright green fluorescence was seen in an elastin fibre layer in the submucosa, which was likely a result of epithelial sloughing. There is a close relationship between the bright green fluorescence pattern observed using AFI bronchoscopy and airway ischaemic damage. We conclude that AFI bronchoscopy may detect airway ischaemic damage after lung transplantation.

  9. Conjunctival Autograft Alone or Combined With Adjuvant Beta-Radiation? A Randomized Clinical Trial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arruda Viani, Gustavo, E-mail: gusviani@gmail.com; Carrara Fonseca, Ellen; Department of Ophthalmology, Marilia Medical School, Marilia, Sao Paulo

    2012-03-01

    Purpose: To evaluate the effectiveness and safety of postoperative low single-dose of beta-irradiation ({beta}-RT) in pterygium comparing conjunctival autograft (CAG) surgery with CAG plus adjuvant {beta}-RT in a randomized clinical trial. Methods: This trial was designed as a prospective, randomized, single-center study. Surgery was performed in all cases according to the CAG technique. One hundred and eight pterygia were postoperatively randomized to CAG + {beta}-RT or CAG alone. In the case of {beta}-RT, a (90) Sr eye applicator was used to deliver 10 Gy to the sclera surface at a dose rate of between 200 and 250 cGy/min. After treatment,more » both an ophthalmologist and a radiation oncologist performed the follow-up examinations. The accumulated data were analyzed using a group sequential test. Results: Between February 2008 and September 2008, 116 eyes with primary pterygium were operated on according to the trial protocol. Adjuvant treatment was performed within 24 h postoperatively. Eight patients were lost to follow-up, resulting in 108 patients who could be analyzed. At a mean follow-up of 18 months (range, 8-33), in the 54 eyes randomized to receive CAG + {beta}-RT, 5 relapses occurred compared with 12 recurrences in the 54 eyes in CAG, for a crude control rate of 90.8 % vs. 78%; p = 0.032, respectively. The treatment complications as hyperemia, total dehiscence of the autograft and dellen were significantly more frequent in the CAG (p < 0.05). The arm of {beta}-RT resulted in better cosmetic results and improves of symptoms than CAG. Conclusions: A low single-dose of {beta}-RT of 10 Gy after CAG surgery was a simple, effective, and safe treatment that reduced the risk of primary pterygium recurrence, improved symptoms after surgery, resulting in a better cosmetic effect than only CAG.« less

  10. Quadriceps Tendon Autograft Medial Patellofemoral Ligament Reconstruction.

    PubMed

    Fink, Christian; Steensen, Robert; Gföller, Peter; Lawton, Robert

    2018-06-01

    Critically evaluate the published literature related to quadriceps tendon (QT) medial patellofemoral ligament (MPFL) reconstruction. Hamstring tendon (HT) MPFL reconstruction techniques have been shown to successfully restore patella stability, but complications including patella fracture are reported. Quadriceps tendon (QT) reconstruction techniques with an intact graft pedicle on the patella side have the advantage that patella bone tunnel drilling and fixation are no longer needed, reducing risk of patella fracture. Several QT MPFL reconstruction techniques, including minimally invasive surgical (MIS) approaches, have been published with promising clinical results and fewer complications than with HT techniques. Parallel laboratory studies have shown macroscopic anatomy and biomechanical properties of QT are more similar to native MPFL than hamstring (HS) HT, suggesting QT may more accurately restore native joint kinematics. Quadriceps tendon MPFL reconstruction, via both open and MIS techniques, have promising clinical results and offer valuable alternatives to HS grafts for primary and revision MPFL reconstruction in both children and adults.

  11. Grafting Technique to Eliminate Rootstock Suckering of Grafted Tomatoes

    USDA-ARS?s Scientific Manuscript database

    Vegetable grafting has been proposed as a technique for avoiding disease problems in tomatoes in open field production. In this study we investigated the current use of grafting in an open field scenario and found a serious problem with the grafting techniques. In the Fall of 2007, commercially pr...

  12. Nanofat grafting under a split-thickness skin graft for problematic wound management.

    PubMed

    Kemaloğlu, Cemal Alper

    2016-01-01

    Obesity and certain medical disorders make the reconstruction of skin defects challenging. Different kind of procedure can be used for these defect, besides, skin grafting is one of the most common and simplest procedure. Fat grafting and stem cells which are located in the adipose tissue have been commonly used in plastic surgery for regeneration and rejuvenation purposes. To decrease graft failure rate we performed nanofat grafting under an autologous split-thickness skin graft in our patient who had a problematic wound. The case of a 35-year-old female patient with a traumatic skin defect on her left anterior crural region is described herein. After subsequent flap reconstruction, the result was disappointing and the defect size was widened. The defect was treated with combined grafting (nanofat grafting under an autologous split-thickness skin graft). At the 6 months follow-up assessment after combined grafting, the integrity of the skin graft was good with excellent pliability. Combined grafting for problematic wounds seems to be a useful technique for cases requiring reconstruction. The potential existence of stem cells may be responsible for the successful result in our patient.

  13. The Use of Platelets to Affect Functional Healing of an Anterior Cruciate Ligament (ACL) Autograft in a Caprine ACL Reconstruction Model

    PubMed Central

    Spindler, Kurt P.; Murray, Martha M.; Carey, James L.; Zurakowski, David; Fleming, Braden C.

    2009-01-01

    Many anterior cruciate ligament (ACL) reconstructions have increased laxity postoperatively. We hypothesized that enhancing an ACL graft with a collagen-platelet composite (CPC) would improve knee laxity and graft structural properties. We also hypothesized the platelet concentration in the CPC would affect these parameters. Twelve goats underwent ACL reconstruction with autologous patellar tendon graft. In six goats, a collagen-platelet composite was placed around the graft (CPC group). In the remaining six goats, the collagen scaffold only was used (COLL group). Three goats were excluded due to complications. After 6 weeks in vivo, anterior–posterior (AP) laxity and tensile properties of the ACL reconstructed knees were measured and normalized against the contralateral intact knee. At a knee flexion angle of 30°, the average increase in AP laxity was 40% less in the CPC group than the COLL group (p = 0.045). At 60°, the AP laxity was 30% less in the CPC group, a difference that was close to statistical significance (p = 0.080). No differences were found between treatment groups with respect to the structural properties (p > 0.30). However, there were significant correlations between serum platelet concentration and AP laxity (R2 = 0.643; p = 0.009), maximum load (R2 = 0.691; p = 0.006), and graft stiffness (R2 = 0.840; p < 0.001). In conclusion, use of a CPC to enhance healing of an allograft ACL reconstruction inversely correlated with early sagittal plane laxity and the systemic platelet count was highly predictive of ACL reconstruction graft strength and stiffness at 6 weeks. These findings emphasize the importance of further research on delineating the effect of platelets in treating of ACL injuries. PMID:19009602

  14. Proximal Tibial Bone Graft

    MedlinePlus

    ... All Site Content AOFAS / FootCareMD / Treatments Proximal Tibial Bone Graft Page Content What is a bone graft? Bone grafts may be needed for various ... the proximal tibia. What is a proximal tibial bone graft? Proximal tibial bone graft (PTBG) is a ...

  15. Quantitative computed tomography and cranial burr holes: a model to evaluate the quality of cranial reconstruction in humans.

    PubMed

    Worm, Paulo Valdeci; Ferreira, Nelson Pires; Ferreira, Marcelo Paglioli; Kraemer, Jorge Luiz; Lenhardt, Rene; Alves, Ronnie Peterson Marcondes; Wunderlich, Ricardo Castilho; Collares, Marcus Vinicius Martins

    2012-05-01

    Current methods to evaluate the biologic development of bone grafts in human beings do not quantify results accurately. Cranial burr holes are standardized critical bone defects, and the differences between bone powder and bone grafts have been determined in numerous experimental studies. This study evaluated quantitative computed tomography (QCT) as a method to objectively measure cranial bone density after cranial reconstruction with autografts. In each of 8 patients, 2 of 4 surgical burr holes were reconstructed with autogenous wet bone powder collected during skull trephination, and the other 2 holes, with a circular cortical bone fragment removed from the inner table of the cranial bone flap. After 12 months, the reconstructed areas and a sample of normal bone were studied using three-dimensional QCT; bone density was measured in Hounsfield units (HU). Mean (SD) bone density was 1535.89 (141) HU for normal bone (P < 0.0001), 964 (176) HU for bone fragments, and 453 (241) HU for bone powder (P < 0.001). As expected, the density of the bone fragment graft was consistently greater than that of bone powder. Results confirm the accuracy and reproducibility of QCT, already demonstrated for bone in other locations, and suggest that it is an adequate tool to evaluate cranial reconstructions. The combination of QCT and cranial burr holes is an excellent model to accurately measure the quality of new bone in cranial reconstructions and also seems to be an appropriate choice of experimental model to clinically test any cranial bone or bone substitute reconstruction.

  16. THE FIXATION OF RADIOPOTASSIUM IN AUTO- AND HOMOGRAFTS OF SKIN IN THE RAT (in Italian)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scortecci, V.

    1962-09-01

    The potassium fixation of auto- and homografts of skin in the rat was studied using K/sup 42/. A slightly higher uptake of K was observed in the autograft than in the homograft as early as the 4th day after grafting. (auth)

  17. Remodeling of ACL Allografts is Inhibited by Peracetic Acid Sterilization

    PubMed Central

    Gonnermann, Johannes; Kamp, Julia; Przybilla, Dorothea; Pruss, Axel

    2008-01-01

    Sterilization of allografts for anterior cruciate ligament (ACL) reconstruction has become an important prerequisite to prevent disease transmission. However, current sterilization techniques impair the biological or mechanical properties of such treated grafts. Peracetic acid (PAA) has been successfully used to sterilize bone allografts without these disadvantages and does not impair the mechanical properties of soft tissue grafts in vitro. We asked whether PAA sterilization would influence recellularization, restoration of crimp length and pattern, and revascularization of ACL grafts during early healing. We used an in vivo sheep model for open ACL reconstruction. We also correlated the histologic findings with the restoration of anteroposterior stability and structural properties during load-to-failure testing. PAA slowed remodeling activity at 6 and 12 weeks compared to nonsterilized allografts and autografts. The mechanical properties of PAA grafts were also reduced compared to these control groups at both time points. We conclude PAA sterilization currently should not be used to sterilize soft tissue grafts typically used in ACL reconstruction. PMID:18491201

  18. Treatment of Venous Aortorenal Bypass Graft Aneurysm Using a Stent-Graft

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Novotny, Jiri, E-mail: jino@medicon.cz; Peregrin, Jan H.; Stribrna, Jarmila

    2010-02-15

    We present the case of a 77-year-old male patient who had undergone a bilateral venous aortorenal bypass graft 30 years previously. Thirteen years previously, the patient was shown to have a decrease in renal function, with mild shrinking of both kidneys; additionally, a stenosis was found in the left proximal anastomosis. At the most recent follow-up visit (1 year previously), ultrasound revealed an aneurysm (42 mm in diameter) of the left renal bypass graft; the finding was confirmed by CT angiography. A significant ostial stenosis of the left renal bypass graft was also confirmed. It was decided to place amore » self-expandable stent-graft into the aneurysm while also attempting to dilate the stenosis. Proximal endoleak after stent-graft placement necessitated the implantation of another, balloon-expandable stent-graft into the bypass graft ostium. Postprocedural angiography and follow-up by CT angiography at 3 months confirmed good patency of the stent-grafts and complete thrombosis of the aneurysmal sac, with preserved kidney perfusion. Renal function remained unaltered, while the hypertension is better controlled.« less

  19. Prediction models of donor arrest and graft utilization in liver transplantation from maastricht-3 donors after circulatory death.

    PubMed

    Davila, D; Ciria, R; Jassem, W; Briceño, J; Littlejohn, W; Vilca-Meléndez, H; Srinivasan, P; Prachalias, A; O'Grady, J; Rela, M; Heaton, N

    2012-12-01

    Shortage of organs for transplantation has led to the renewed interest in donation after circulatory-determination of death (DCDD). We conducted a retrospective analysis (2001-2009) and a subsequent prospective validation (2010) of liver Maastricht-Category-3-DCDD and donation-after-brain-death (DBD) offers to our program. Accepted and declined offers were compared. Accepted DCDD offers were divided into donors who went on to cardiac arrest and those who did not. Donors who arrested were divided into those producing grafts that were transplanted or remained unused. Descriptive comparisons and regression analyses were performed to assess predictor models of donor cardiac arrest and graft utilization. Variables from the multivariate analysis were prospectively validated. Of 1579 DCDD offers, 621 were accepted, and of these, 400 experienced cardiac arrest after withdrawal of support. Of these, 173 livers were transplanted. In the DCDD group, donor age < 40 years, use of inotropes and absence of gag/cough reflexes were predictors of cardiac arrest. Donor age >50 years, BMI >30, warm ischemia time >25 minutes, ITU stay >7 days and ALT ≥ 4× normal rates were risk factors for not using the graft. These variables had excellent sensitivity and specificity for the prediction of cardiac arrest (AUROC = 0.835) and graft use (AUROC = 0.748) in the 2010 prospective validation. These models can feasibly predict cardiac arrest in potential DCDDs and graft usability, helping to avoid unnecessary recoveries and healthcare expenditure. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.

  20. Microporous pure beta-tricalcium phosphate implants for press-fit fixation of anterior cruciate ligament grafts: strength and healing in a sheep model.

    PubMed

    Mayr, Hermann O; Dietrich, Markwart; Fraedrich, Franz; Hube, Robert; Nerlich, Andreas; von Eisenhart-Rothe, Rüdiger; Hein, Werner; Bernstein, Anke

    2009-09-01

    A sheep study was conducted to test a press-fit technique using microporous pure beta-tricalcium phosphate (beta-TCP) dowels for fixation of the anterior cruciate ligament (ACL) graft. Microporous (5 mum) cylindrical plugs of beta-TCP (diameter, 7 mm; length, 25 mm) with interconnecting pores were used. The material featured a novel configuration of structure and surface geometry. Implants were tested by use of press-fit fixation of ACL grafts with and without bone blocks in 42 sheep over a period of 24 weeks. Biomechanical, radiologic, histologic, and immunohistochemical evaluations were performed. In load-to-failure tests at 6, 12, and 24 weeks after surgery, the intra-articular graft always failed, not the fixation. Grafts showed bony fixation in the tunnel at 6 weeks and primary healing at the junction of the tunnel and joint after 24 weeks. Tricalcium phosphate was resorbed and simultaneously replaced by bone. Remodeling was still incomplete at 24 weeks. In the sheep model microporous beta-TCP implants used with press-fit fixation of ACL grafts permit early functional rehabilitation. After 6 weeks, the graft is fixed by woven bone or bony integration. Implanted microporous tricalcium phosphate is resorbed and replaced by bone. In a sheep model we showed that primary healing of ACL grafts with resorption and bony replacement of the fixating implant can be achieved by means of press-fit fixation with pure beta-TCP.

  1. [Is local bone graft sufficient to maintain the surgical correction in adolescent idiopathic scoliosis curves?].

    PubMed

    Mardomingo, A; Sánchez-Mariscal, F; Alvarez, P; Pizones, J; Zúñica, L; Izquierdo, E

    2013-01-01

    The purpose of this study was to compare postoperative clinical and radiological results in adolescent idiopathic scoliosis curves treated by posterior arthrodesis using autogenous bone graft from iliac crest (CI) versus only local autograft bone (HL). A retrospective matched cohort study was conducted on 73 patients (CI n=37 and HL n=36) diagnosed with adolescent idiopathic scoliosis and treated surgically by posterior arthrodesis. The mean post-operative follow-up was 126 months in the CI group vs. 66 months in the HL group. The radiographic data collected consisted of preoperative, postoperative, and final follow-up antero-posterior and lateral full-length radiographs. Loss of correction and quality of arthrodesis were evaluated by comparing the scores obtained from the Spanish version of the SRS-22 questionnaire. There were significant differences in the post-operative results as regards the correction of the Cobb angle of the main curve (HL 61 ± 15% vs. CI 51 ± 14%, P<.004), however a greater loss of correction was found in the local bone group (CI 4.5 ± 7.3° vs. HL 8.5 ± 6.3°, P=.02). There were no significant differences as regards the correction of the Cobb angle of the main curve at the end of follow-up. There were no clinical differences between the two groups in the SRS-22 scores. At 5 years of follow-up, there was a statistically significant greater loss of radiographic correction at the end of final follow-up in the local bone graft group. However clinical differences were not observed as regards the SRS-22 scores. Copyright © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

  2. Bone Graft Alternatives

    MedlinePlus

    ... Spine Treatment Spondylolisthesis BLOG FIND A SPECIALIST Treatments Bone Graft Alternatives Patient Education Committee Patient Education Committee ... procedure such as spinal fusion. What Types of Bone Grafts are There? Bone grafts that are transplanted ...

  3. Toward a patient-specific tissue engineered vascular graft

    PubMed Central

    Best, Cameron; Strouse, Robert; Hor, Kan; Pepper, Victoria; Tipton, Amy; Kelly, John; Shinoka, Toshiharu; Breuer, Christopher

    2018-01-01

    Integrating three-dimensional printing with the creation of tissue-engineered vascular grafts could provide a readily available, patient-specific, autologous tissue source that could significantly improve outcomes in newborns with congenital heart disease. Here, we present the recent case of a candidate for our tissue-engineered vascular graft clinical trial deemed ineligible due to complex anatomical requirements and consider the application of three-dimensional printing technologies for a patient-specific graft. We 3D-printed a closed-disposable seeding device and validated that it performed equivalently to the traditional open seeding technique using ovine bone marrow–derived mononuclear cells. Next, our candidate’s preoperative imaging was reviewed to propose a patient-specific graft. A seeding apparatus was then designed to accommodate the custom graft and 3D-printed on a commodity fused deposition modeler. This exploratory feasibility study represents an important proof of concept advancing progress toward a rationally designed patient-specific tissue-engineered vascular graft for clinical application. PMID:29568478

  4. DNA nanosensor surface grafting and salt dependence

    NASA Astrophysics Data System (ADS)

    Carvalho, B. G.; Fagundes, J.; Martin, A. A.; Raniero, L.; Favero, P. P.

    2013-02-01

    In this paper we investigated the Paracoccidoides brasiliensis fungus nanosensor by simulations of simple strand DNA grafting on gold nanoparticle. In order to improve the knowledge of nanoparticle environment, the addiction of salt solution was studied at the models proposed by us. Nanoparticle and DNA are represented by economic models validated by us in this paper. In addition, the DNA grafting and salt influences are evaluated by adsorption and bond energies calculations. This theoretical evaluation gives support to experimental diagnostics techniques of diseases.

  5. Transplanting Human Skin Grafts onto Nude Mice to Model Skin Scars.

    PubMed

    Ding, Jie; Tredget, Edward E

    2017-01-01

    Hypertrophic scar (HTS) is a common outcome of deep dermal wound healing mainly followed mechanical, chemical, and thermal injuries in the skin. Because of the lack of the most effective prevention and treatment, it is particularly important to establish an ideal dermal animal model for improving the understanding of the pathogenesis and exploring therapeutic approaches of HTS. Compared to other dermal fibrotic animal models in rabbits, red Duroc pigs, guinea pigs, rats, and mice, the approach that uses normal human split-thickness skin grafted onto nude or other immunodeficient mice which develop scars that resemble human HTS offers the advantages of lower cost, easier manipulation, and shorter research period. In this chapter, we will introduce the detailed procedures to create the ideal dermal fibrotic mouse model.

  6. Biomechanical comparison of graft fixation at 30° and 90° of elbow flexion for ulnar collateral ligament reconstruction by the docking technique.

    PubMed

    Cohen, Steven B; Woods, Daniel P; Siegler, Sorin; Dodson, Christopher C; Namani, Ramya; Ciccotti, Michael G

    2015-02-01

    Ulnar collateral ligament (UCL) injuries have been successfully treated by the docking reconstruction. Although fixation of the graft has been suggested at 30° of elbow flexion, no quantitative biomechanical data exist to provide guidelines for the optimal elbow flexion angle for graft fixation. Testing was conducted on 10 matched pairs of cadaver elbows with use of a loading system and optoelectric tracking device. After biomechanical data on the native UCL were obtained, reconstruction by the docking technique was performed with use of palmaris longus autograft with one elbow fixated at 30° and the contralateral elbow at 90° of elbow flexion. Biomechanical testing was undertaken on these specimens. The load to failure of the native UCL (mean, 20.1 N-m) was significantly higher (P = .004) than that of the reconstructed UCL (mean, 4.6 N-m). There was no statistically significant difference in load to failure of the UCL reconstructions fixated at 30° of elbow flexion (average, 4.86 N-m) compared with those at 90° (average, 4.35 N-m). Elbows reconstructed at 30° and 90° of elbow flexion produced similar kinematic coupling and valgus laxity characteristics compared with each other and with the intact UCL. Although not statistically significant, the reconstructions fixated at 30° more closely resembled the biomechanical characteristics of the intact elbow than did reconstructions fixated at 90°. No statistically significant difference was found in comparing the docking technique of UCL reconstruction with graft fixation at 30° vs. 90° of elbow flexion. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  7. Confined dynamics of grafted polymer chains in solutions of linear polymer

    DOE PAGES

    Poling-Skutvik, Ryan D.; Olafson, Katy N.; Narayanan, Suresh; ...

    2017-09-11

    Here, we measure the dynamics of high molecular weight polystyrene grafted to silica nanoparticles dispersed in semidilute solutions of linear polymer. Structurally, the linear free chains do not penetrate the grafted corona but increase the osmotic pressure of the solution, collapsing the grafted polymer and leading to eventual aggregation of the grafted particles at high matrix concentrations. Dynamically, the relaxations of the grafted polymer are controlled by the solvent viscosity according to the Zimm model on short time scales. On longer time scales, the grafted chains are confined by neighboring grafted chains, preventing full relaxation over the experimental time scale.more » Adding free linear polymer to the solution does not affect the initial Zimm relaxations of the grafted polymer but does increase the confinement of the grafted chains. Finally, our results elucidate the physics underlying the slow relaxations of grafted polymer.« less

  8. Confined dynamics of grafted polymer chains in solutions of linear polymer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Poling-Skutvik, Ryan D.; Olafson, Katy N.; Narayanan, Suresh

    Here, we measure the dynamics of high molecular weight polystyrene grafted to silica nanoparticles dispersed in semidilute solutions of linear polymer. Structurally, the linear free chains do not penetrate the grafted corona but increase the osmotic pressure of the solution, collapsing the grafted polymer and leading to eventual aggregation of the grafted particles at high matrix concentrations. Dynamically, the relaxations of the grafted polymer are controlled by the solvent viscosity according to the Zimm model on short time scales. On longer time scales, the grafted chains are confined by neighboring grafted chains, preventing full relaxation over the experimental time scale.more » Adding free linear polymer to the solution does not affect the initial Zimm relaxations of the grafted polymer but does increase the confinement of the grafted chains. Finally, our results elucidate the physics underlying the slow relaxations of grafted polymer.« less

  9. Effect of Intraoperative Platelet-Rich Plasma Treatment on Postoperative Donor Site Knee Pain in Patellar Tendon Autograft Anterior Cruciate Ligament Reconstruction: A Double-Blind Randomized Controlled Trial.

    PubMed

    Walters, Brian L; Porter, David A; Hobart, Sarah J; Bedford, Benjamin B; Hogan, Daniel E; McHugh, Malachy M; Klein, Devon A; Harousseau, Kendall; Nicholas, Stephen J

    2018-05-01

    Donor site morbidity in the form of anterior knee pain is a frequent complication after bone-patellar tendon-bone (BPTB) autograft anterior cruciate ligament (ACL) reconstruction. Hypothesis/Purpose: The purpose was to examine the effect of the intraoperative administration of platelet-rich plasma (PRP) on postoperative kneeling pain. It was hypothesized that PRP treatment would reduce knee pain. Randomized controlled trial; Level of evidence, 2. Fifty patients (mean ± SD age, 30 ± 12 years) undergoing BPTB ACL autograft reconstruction were randomized to the PRP (n = 27) or sham (n = 23) treatment. In either case, 10 mL of venous blood was drawn before the induction of anesthesia and either discarded (sham) or processed (PRP) for preparation of a PRP gel to be later mixed with donor site bone chips and inserted into the patellar defect. At 12 weeks, 6 months, 1 year, and 2 years after surgery, patients completed International Knee Documentation Committee (IKDC) forms and visual analog scale pain scores for activities of daily living and kneeling. Healing indices at the donor site were assessed by routine noncontrast magnetic resonance imaging (MRI) at 6 months. Mixed-model analysis of variance was used to assess the effect of PRP on patient symptoms and MRI indices of donor site healing, as measured by the width of the donor site defect. Kneeling pain, pain with activities of daily living, and IKDC scores were not different between treatment groups at any of the time intervals ( P = .08-.83). Kneeling pain improved from 12 weeks to 6 months and from 1 to 2 years ( P < .05). IKDC scores improved substantially from 12 weeks to 6 months ( P < .001) and continued to improve to 2 years (PRP, 86 ± 19; sham, 89 ± 10). MRI indices of donor site healing were not different between treatment groups ( P = .53-.90). Whether randomized to receive PRP in their patellar defect or not, patients continued to have similar levels of kneeling pain and patellar defect sizes after

  10. Delayed grafting for banked skin graft in lymph node flap transfer.

    PubMed

    Ciudad, Pedro; Date, Shivprasad; Orfaniotis, Georgios; Dower, Rory; Nicoli, Fabio; Maruccia, Michele; Lin, Shu-Ping; Chuang, Chu-Yi; Chuang, Tsan-Yu; Wang, Gou-Jen; Chen, Hung-Chi

    2017-02-01

    Over the last decade, lymph node flap (LNF) transfer has turned out to be an effective method in the management of lymphoedema of extremities. Most of the time, the pockets created for LNF cannot be closed primarily and need to be resurfaced with split thickness skin grafts. Partial graft loss was frequently noted in these cases. The need to prevent graft loss on these iatrogenic wounds made us explore the possibility of attempting delayed skin grafting. We have herein reported our experience with delayed grafting with autologous banked split skin grafts in cases of LNF transfer for lymphoedema of the extremities. Ten patients with International Society of Lymphology stage II-III lymphoedema of upper or lower extremity were included in this study over an 8-month period. All patients were thoroughly evaluated and subjected to lymph node flap transfer. The split skin graft was harvested and banked at the donor site, avoiding immediate resurfacing over the flap. The same was carried out in an aseptic manner as a bedside procedure after confirming flap viability and allowing flap swelling to subside. Patients were followed up to evaluate long-term outcomes. Flap survival was 100%. Successful delayed skin grafting was done between the 4th and 6th post-operative day as a bedside procedure under local anaesthesia. The split thickness skin grafts (STSG) takes more than 97%. One patient needed additional medications during the bedside procedure. All patients had minimal post-operative pain and skin graft requirement. The patients were also reported to be satisfied with the final aesthetic results. There were no complications related to either the skin grafts or donor sites during the entire period of follow-up. Delayed split skin grafting is a reliable method of resurfacing lymph node flaps and has been shown to reduce the possibility of flap complications as well as the operative time and costs. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  11. Impact of pregnancy on autograft dilatation and aortic valve function following the Ross procedure.

    PubMed

    Carvajal, Horacio G; Lindley, Kathryn J; Shah, Trupti; Brar, Anoop K; Barger, Philip M; Billadello, Joseph J; Eghtesady, Pirooz

    2018-03-01

    The effects of pregnancy on autograft dilatation and neoaortic valve function in patients with a Ross procedure have not been studied. We sought to evaluate the effect of pregnancy on autograft dilatation and valve function in these patients with the goal of determining whether pregnancy is safe after the Ross procedure. A retrospective chart review of female patients who underwent a Ross procedure was conducted. Medical records for 51 patients were reviewed. Among the 33 patients who met inclusion criteria, 11 became pregnant after surgery and 22 did not. Echocardiographic reports were used to record aortic root diameter and aortic insufficiency before, during, and after pregnancy. Patient's charts were reviewed for reinterventions and complications. Primary endpoints included reinterventions, aortic root dilation of ≥5 cm, aortic insufficiency degree ≥ moderate, and death. There were 18 pregnancies carried beyond 20 weeks in 11 patients. There was no significant difference in aortic root diameter between nulliparous patients and parous patients prior to their first pregnancy (3.53 ± 0.44 vs 3.57 ± 0.69 cm, P = .74). There was no significant change in aortic root diameter after first pregnancy (3.7 ± 0.4 cm, P = .056) although there was significant dilatation after the second (4.3 ± 0.7 cm, P = .009) and third (4.5 ± 0.7 cm, P = .009) pregnancies. Freedom from combined endpoints was significantly higher for patients in the pregnancy group than those in the nonpregnancy group (P = .002). Pregnancy was not associated with significantly increased adverse events in patients following the Ross procedure. Special care should be taken after the first pregnancy, as multiparity may lead to increased neoaortic dilatation. © 2017 Wiley Periodicals, Inc.

  12. Descriptive Epidemiology of the Multicenter ACL Revision Study (MARS) Cohort

    PubMed Central

    2013-01-01

    Background Revision anterior cruciate ligament (ACL) reconstruction has worse outcomes than primary reconstructions. Predictors for these worse outcomes are not known. The Multicenter ACL Revision Study (MARS) Group was developed to perform a multisurgeon, multicenter prospective longitudinal study to obtain sufficient subjects to allow multivariable analysis to determine predictors of clinical outcome. Purpose To describe the formation of MARS and provide descriptive analysis of patient demographics and clinical features for the initial 460 enrolled patients to date in this prospective cohort. Study Design Cross-sectional study; Level of evidence, 2. Methods After training and institutional review board approval, surgeons began enrolling patients undergoing revision ACL reconstruction, recording patient demographics, previous ACL reconstruction methods, intra-articular injuries, and current revision techniques. Enrolled subjects completed a questionnaire consisting of validated patient-based outcome measures. Results As of April 1, 2009, 87 surgeons have enrolled a total of 460 patients (57% men; median age, 26 years). For 89%, the reconstruction was the first revision. Mode of failure as deemed by the revising surgeon was traumatic (32%), technical (24%), biologic (7%), combination (37%), infection (<1%), and no response (<1%). Previous graft present at the time of injury was 70% autograft, 27% allograft, 2% combination, and 1% unknown. Sixty-two percent were more than 2 years removed from their last reconstruction. Graft choice for revision ACL reconstruction was 45% autograft, 54% allograft, and more than 1% both allograft and autograft. Meniscus and/or chondral damage was found in 90% of patients. Conclusion The MARS Group has been able to quickly accumulate the largest revision ACL reconstruction cohort reported to date. Traumatic reinjury is deemed by surgeons to be the most common single mode of failure, but a combination of factors represents the most

  13. Randomized, Paired-site Comparison of Autologous Engineered Skin Substitutes and Split-thickness Skin Graft for Closure of Extensive, Full-thickness Burns

    PubMed Central

    Boyce, Steven T.; Simpson, Peggy S.; Rieman, Mary T.; Warner, Petra M.; Yakuboff, Kevin P.; Bailey, J. Kevin; Nelson, Judith K.; Fowler, Laura A.; Kagan, Richard J.

    2016-01-01

    Objectives Stable closure of full-thickness burn wounds remains a limitation to recovery from burns of greater than 50% of the total body surface area (TBSA). Hypothetically, engineered skin substitutes (ESS) consisting of autologous keratinocytes and fibroblasts attached to collagen-based scaffolds may reduce requirements for donor skin, and decrease mortality. Methods ESS were prepared from split-thickness skin biopsies collected after enrollment of 16 pediatric burn patients into an approved study protocol. ESS and split-thickness autograft (AG) were applied to 15 subjects with full-thickness burns involving a mean of 76.9% TBSA. Data consisted of photographs, tracings of donor skin and healed wounds, comparison of mortality with the National Burn Repository (NBR), correlation of TBSA closed wounds with TBSA full-thickness burn, frequencies of regrafting, and immunoreactivity to the biopolymer scaffold. Results One subject expired before ESS application, and 15 subjects received 2056 ESS grafts. The ratio of closed wound to donor areas was 108.7±9.7 for ESS compared with a maximum of 4.0±0.0 for AG. Mortality for enrolled subjects was 6.25%, and 30.3% for a comparable population from the NBR (p<0.05). Engraftment was 83.5±2.0% for ESS and 96.5±0.9 for AG. Percentage TBSA closed was 29.9±3.3% for ESS, and 47.0±2.0 for AG. These values were significantly different between the graft types. Correlation of % TBSA closed with ESS with % TBSA full-thickness burn generated an R2 value of 0.65 (p<0.001). Conclusions These results indicate that autologous ESS reduce mortality and requirements for donor skin harvesting, for grafting of full-thickness burns of greater than 50% TBSA. PMID:27404165

  14. Randomized, Paired-Site Comparison of Autologous Engineered Skin Substitutes and Split-Thickness Skin Graft for Closure of Extensive, Full-Thickness Burns.

    PubMed

    Boyce, Steven T; Simpson, Peggy S; Rieman, Mary T; Warner, Petra M; Yakuboff, Kevin P; Bailey, J Kevin; Nelson, Judith K; Fowler, Laura A; Kagan, Richard J

    Stable closure of full-thickness burn wounds remains a limitation to recovery from burns of greater than 50% of the total body surface area (TBSA). Hypothetically, engineered skin substitutes (ESS) consisting of autologous keratinocytes and fibroblasts attached to collagen-based scaffolds may reduce requirements for donor skin, and decrease mortality. ESS were prepared from split-thickness skin biopsies collected after enrollment of 16 pediatric burn patients into an approved study protocol. ESS and split-thickness autograft (AG) were applied to 15 subjects with full-thickness burns involving a mean of 76.9% TBSA. Data consisted of photographs, tracings of donor skin and healed wounds, comparison of mortality with the National Burn Repository, correlation of TBSA closed wounds with TBSA full-thickness burn, frequencies of regrafting, and immunoreactivity to the biopolymer scaffold. One subject expired before ESS application, and 15 subjects received 2056 ESS grafts. The ratio of closed wound to donor areas was 108.7 ± 9.7 for ESS compared with a maximum of 4.0 ± 0.0 for AG. Mortality for enrolled subjects was 6.25%, and 30.3% for a comparable population from the National Burn Repository (P < .05). Engraftment was 83.5 ± 2.0% for ESS and 96.5 ± 0.9% for AG. Percentage TBSA closed was 29.9 ± 3.3% for ESS, and 47.0 ± 2.0% for AG. These values were significantly different between the graft types. Correlation of % TBSA closed with ESS with % TBSA full-thickness burn generated an R value of 0.65 (P < .001). These results indicate that autologous ESS reduce mortality and requirements for donor skin harvesting, for grafting of full-thickness burns of greater than 50% TBSA.

  15. Compliance effects on small diameter polyurethane graft patency.

    PubMed

    Uchida, N; Kambic, H; Emoto, H; Chen, J F; Hsu, S; Murabayshi, S; Harasaki, H; Nosé, Y

    1993-10-01

    Microporous compliance matched and noncompliant grafts were compared in a dog carotid artery interposition model. We fabricated 4 mm diameter sponge type polyurethane (Biomer) tubes 5 cm in length with a 0.5 mm wall thickness. The luminal surface was covered with a 50 microns coating of cross-linked gelatin. Compliance was measured in vitro and in vivo by volume and vessel diameter changes. Over a mean arterial pressure range of 55-155 mm Hg, the diameter changes of grafts and stump arteries were measured in situ using an ultrasonic Hokanson device. Compliance matched grafts were found to have the same in vitro compliance values as the natural canine carotid at a mean arterial pressure of 100 mm Hg. Compliance matched and noncompliant grafts had values of 10.3 +/- 1.3 and 0.9 +/- 0.1 x 10(-2) mm Hg, respectively. End to end arterial anastomoses were constructed between the graft and the host arteries. The use of synthetic grafts with matched compliance to the adjacent natural vessels has been advocated as the ideal solution to circumvent the problems of graft failure. These studies indicate that compliance values for compliance matched grafts decreased immediately after implantation (from 10.3 to 6.5 x 10(-2) %/mm Hg) and within 6 weeks decreased to 3.6 x 10(-2) %/mm Hg. The compliance values for noncompliant grafts remained constant throughout the test period. At autopsy all grafts showed a tightly adhered tissue capsule. The thickness of the anastomotic hyperplasia at the distal sites of compliance matched grafts was significantly different (P < .05) than that of the adjacent artery. The patency for compliant and noncompliant grafts was 64% and 50%, respectively. Evidence for polyurethane graft degradation was obtained by Fourier transform infrared spectroscopy and gel permeation chromatography analysis of patent explants. Compliance mismatch alone does not contribute to graft failure, however, material degradation, suture technique and/or capsule formation can

  16. Prolonged survival of reconstituted skin grafts without immunosuppression.

    PubMed

    Sasamoto, Y; Alexander, J W; Babcock, G F

    1990-01-01

    Reconstituted skin composed of a cultured allogeneic epithelial sheet (CAES) and a cultured allogeneic dermis (CAD) was evaluated in a rat model to determine whether it could survive for a prolonged period without immunosuppression. Additionally, free CAD grafts were evaluated for their suitability as dermal substitutes. Male Buffalo rats were used as donors and male Lewis rats as recipients. Split-thickness skin obtained from Buffalo rats was separated into epidermis and dermis by means of Dispase II enzyme. The epidermal layers were minced and trypsinized. Then dispersed single keratinocytes were inoculated onto a irradiated 3T3 cell feeder layer. After a suitable period, a confluent cultured keratinocyte layer was detached and provided CAES grafts. Cultured allogeneic dermis grafts were prepared from cultures of the dermal component. Cultured allogeneic dermis grafts, covered by split thickness isografts (STIG) or local skin flaps, became revascularized at a rate of 94.6% and 90.9%, respectively, 7 days after grafting. However, only 25% of CAD grafts covered by synthetic materials became vascularized. Four types of wound coverage were compared including: (1) CAES grafts, (2) CAES over CAD grafts, (3) split-thickness isografts, and (4) STIG over CAD grafts. In groups 2 and 4, CAD grafts were applied 7 days before CAES grafts or STIG. Grafts of groups 1 and 2 were successful in only 36.7% and 31.1% of the animals and resulted in a high rate of wound contracture--72.4%, 66.7%, respectively. On the other hand, in groups 3 and 4, higher average rates of revascularization (92.0% and 88.3%) and lower rates of wound contracture (25.4% and 24.2%) were obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Neuro-peptide treatment with Cerebrolysin improves the survival of neural stem cell grafts in an APP transgenic model of Alzheimer disease.

    PubMed

    Rockenstein, Edward; Desplats, Paula; Ubhi, Kiren; Mante, Michael; Florio, Jazmin; Adame, Anthony; Winter, Stefan; Brandstaetter, Hemma; Meier, Dieter; Masliah, Eliezer

    2015-07-01

    Neural stem cells (NSCs) have been considered as potential therapy in Alzheimer's disease (AD) but their use is hampered by the poor survival of grafted cells. Supply of neurotrophic factors to the grafted cells has been proposed as a way to augment survival of the stem cells. In this context, we investigated the utility of Cerebrolysin (CBL), a peptidergic mixture with neurotrophic-like properties, as an adjunct to stem cell therapy in an APP transgenic (tg) model of AD. We grafted murine NSCs into the hippocampus of non-tg and APP tg that were treated systemically with CBL and analyzed after 1, 3, 6 and 9months post grafting. Compared to vehicle-treated non-tg mice, in the vehicle-treated APP tg mice there was considerable reduction in the survival of the grafted NSCs. Whereas, CBL treatment enhanced the survival of NSCs in both non-tg and APP tg with the majority of the surviving NSCs remaining as neuroblasts. The NSCs of the CBL treated mice displayed reduced numbers of caspase-3 and TUNEL positive cells and increased brain derived neurotrophic factor (BDNF) and furin immunoreactivity. These results suggest that CBL might protect grafted NSCs and as such be a potential adjuvant therapy when combined with grafting. Copyright © 2015. Published by Elsevier B.V.

  18. The use of cultured epithelial autograft in the treatment of major burn injuries: a critical review of the literature.

    PubMed

    Wood, F M; Kolybaba, M L; Allen, P

    2006-06-01

    The need to achieve rapid wound closure in patients with massive burns and limited skin donor sites led to the investigation of in vitro cellular expansion of keratinocytes. The use of cultured epithelial autografts (CEA) was first reported in the treatment of major burns in 1981. Since that time, support for the use of CEA has varied, ranging from 'a useful agent' to having 'no demonstrable effect on the outcome of extensively burned patients'. This critical review of the literature examines issues associated with the use of CEA and the introduction of the technology into clinical practice. The factors potentially limiting the use of cultured CEA are the time necessary to culture CEA sheets, the reliability of 'take', vulnerability of grafts on the newly healed surface, long-term durability and the cost implications of such treatment. The available literature was located and critically evaluated using the Australian National Health and Medical Research Council Guidelines. In the identified literature, the level of evidence to support the use of CEA in major burn injures is limited and often restricted to case studies and case series with no Level 1 evidence currently available. The main question arising 'Does CEA have a role in the treatment of major burns?' has proven difficult to answer due to the wide variation in both the quality of study design and the findings. At best, the literature review has highlighted areas of concern that have hindered the successful use of CEA. Our review critically evaluates the use of CEA and explores the advances in techniques towards attempting to improve reliable clinical implementation of CEA. The need for higher level research into the use of CEA is emphasised by this review.

  19. A review of negative-pressure wound therapy in the management of burn wounds.

    PubMed

    Kantak, Neelesh A; Mistry, Riyam; Halvorson, Eric G

    2016-12-01

    Negative pressure has been employed in various aspects of burn care and the aim of this study was to evaluate the evidence for each of those uses. The PubMed and Cochrane CENTRAL databases were queried for articles in the following areas: negative pressure as a dressing for acute burns, intermediate treatment prior to skin grafting, bolster for skin autografts, dressing for integration of dermal substitutes, dressing for skin graft donor sites, and integrated dressing in large burns. Fifteen studies met our inclusion criteria. One study showed negative pressure wound therapy improved perfusion in acute partial-thickness burns, 8 out of 9 studies showed benefits when used as a skin graft bolster dressing, 1 out of 2 studies showed improved rate of revascularization when used over dermal substitutes, and 1 study showed increased rate of re-epithelialization when used over skin graft donor sites. Negative pressure can improve autograft take when used as a bolster dressing. There is limited data to suggest that it may also improve the rate of revascularization of dermal substitutes and promote re-epithelialization of skin graft donor sites. Other uses suggested by studies that did not meet our inclusion criteria include improving vascularity in acute partial-thickness burns and as an integrated dressing for the management of large burns. Further studies are warranted for most clinical applications to establish negative pressure as an effective adjunct in burn wound care. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  20. Nerve stepping stone has minimal impact in aiding regeneration across long acellular nerve allografts.

    PubMed

    Yan, Ying; Hunter, Daniel A; Schellhardt, Lauren; Ee, Xueping; Snyder-Warwick, Alison K; Moore, Amy M; Mackinnon, Susan E; Wood, Matthew D

    2018-02-01

    Acellular nerve allografts (ANAs) yield less consistent favorable outcomes compared with autografts for long gap reconstructions. We evaluated whether a hybrid ANA can improve 6-cm gap reconstruction. Rat sciatic nerve was transected and repaired with either 6-cm hybrid or control ANAs. Hybrid ANAs were generated using a 1-cm cellular isograft between 2.5-cm ANAs, whereas control ANAs had no isograft. Outcomes were assessed by graft gene and marker expression (n = 4; at 4 weeks) and motor recovery and nerve histology (n = 10; at 20 weeks). Hybrid ANAs modified graft gene and marker expression and promoted modest axon regeneration across the 6-cm defect compared with control ANA (P < 0.05), but yielded no muscle recovery. Control ANAs had no appreciable axon regeneration across the 6-cm defect. A hybrid ANA confers minimal motor recovery benefits for regeneration across long gaps. Clinically, the authors will continue to reconstruct long nerve gaps with autografts. Muscle Nerve 57: 260-267, 2018. © 2017 Wiley Periodicals, Inc.

  1. Synovial Mesenchymal Stem Cells Promote Meniscus Regeneration Augmented by an Autologous Achilles Tendon Graft in a Rat Partial Meniscus Defect Model

    PubMed Central

    Ozeki, Nobutake; Muneta, Takeshi; Matsuta, Seiya; Koga, Hideyuki; Nakagawa, Yusuke; Mizuno, Mitsuru; Tsuji, Kunikazu; Mabuchi, Yo; Akazawa, Chihiro; Kobayashi, Eiji; Saito, Tomoyuki; Sekiya, Ichiro

    2015-01-01

    Although meniscus defects and degeneration are strongly correlated with the later development of osteoarthritis, the promise of regenerative medicine strategies is to prevent and/or delay the disease's progression. Meniscal reconstruction has been shown in animal models with tendon grafting and transplantation of mesenchymal stem cells (MSCs); however, these procedures have not shown the same efficacy in clinical studies. Here, our aim was to investigate the ability of tendon grafts pretreated with exogenous synovial-derived MSCs to prevent cartilage degeneration in a rat partial meniscus defect model. We removed the anterior half of the medial meniscus and grafted autologous Achilles tendons with or without a 10-minute pretreatment of the tendon with synovial MSCs. The meniscus and surrounding cartilage were evaluated at 2, 4, and 8 weeks (n = 5). Tendon grafts increased meniscus size irrespective of synovial MSCs. Histological scores for regenerated menisci were better in the tendon + MSC group than in the other two groups at 4 and 8 weeks. Both macroscopic and histological scores for articular cartilage were significantly better in the tendon + MSC group at 8 weeks. Implanted synovial MSCs survived around the grafted tendon and native meniscus integration site by cell tracking assays with luciferase+, LacZ+, DiI+, and/or GFP+ synovial MSCs and/or GFP+ tendons. Flow cytometric analysis showed that transplanted synovial MSCs retained their MSC properties at 7 days and host synovial tissue also contained cells with MSC characteristics. Synovial MSCs promoted meniscus regeneration augmented by autologous Achilles tendon grafts and prevented cartilage degeneration in rats. Stem Cells 2015;33:1927–1938 PMID:25993981

  2. Restoration of fresh cat ovarian tissue function by autografting to subcutaneous tissue: A pilot study.

    PubMed

    Leonel, Ellen C R; Vilela, Janice M V; Paiva, Raísa E G; Jivago, José L P R; Amaral, Rodrigo S; Lucci, Carolina M

    2018-01-01

    Ovarian tissue transplantation could be a valuable technique for the preservation of endangered animals. The domestic cat affords an adequate experimental model for studies aimed at wild felids due to its phylogenetic similarity. Thus, this pilot study evaluated the efficacy of cat ovarian tissue autotransplantation to a peripheral site. Three adult queens were submitted to ovariohysterectomy. The ovaries were fragmented into eight pieces; two were fixed as a control and six were transplanted to subcutaneous tissue of the dorsal neck. Grafts were monitored weekly by ultrasound and fecal samples collected daily in order to monitor estradiol levels. Grafts were recovered on Days: 7, 14, 28, 49 and 63 post-transplantation for histological analyses. One graft was maintained in one animal for 8 months. A total of 2466 ovarian follicles were analyzed: 1406 primordial and 1060 growing follicles. All animals presented antral follicles in one or more of the grafts. The percentage of morphologically normal primordial follicles was always higher than 80%, except for Day 7 transplants. Although the proportion of growing follicles increased after transplantation, there was a general decrease in the percentage of morphologically normal growing follicles from Day 7 onwards. All animals demonstrated at least three estradiol peaks during the 63-day period, and one animal exhibited estrous behaviour on three occasions. Hormonal peaks directly correlated with the visualization of antral follicles (by ultrasound and/or histology) and the observation of estrous behaviour. Long-term results on one female showed the concentration of 37.8 pg/mL of serum estradiol on Day 233 post-grafting and the female exhibited estrous behaviour on several occasions. This graft showed one antral follicle, one luteinized follicle and two preantral follicles. In conclusion, cat ovary autotransplantation to the subcutaneous tissue restored ovarian function, with hormone production and antral follicle

  3. Osteochondral graft from the pre-achilles area for replacement of articular surface defects

    NASA Astrophysics Data System (ADS)

    Kuznetsov, V. V.; Pahomov, I. A.; Prohorenko, V. M.; Sadovoy, M. A.; Korel, A. V.; Zaydman, A. M.; Repin, A. V.; Gudi, S. M.; Korochkin, S. B.

    2017-09-01

    We substantiate a new technique for obtaining osteochondral autograft to replace osteochondral defects resulting from various lesions of the talar trochlea by means of morphological examination of the following microslides: talar cartilage (cadaver material), cartilage portion of the pre-achilles zone of the calcaneum, lateral femoral condyle, and necrotic area of the talus. Examination of the specimens of the pre-achilles cartilage of the calcaneus revealed a large number of poorly differentiated chondroblasts in the homogeneously stained extracellular matrix; the presence of all zones (superficial zone, zone of columnar structures, and "tidemark"). This is indicative of structural and functional preservation of this cartilage, which therefore can be considered as an autograft material.

  4. Ethylene vinyl acetate based radiation grafted hydrophilic matrices: Process parameter standardization, grafting kinetics and characterization

    NASA Astrophysics Data System (ADS)

    Chaudhari, C. V.; Mondal, R. K.; Dubey, K. A.; Grover, V.; Panicker, L.; Bhardwaj, Y. K.; Varshney, L.

    2016-08-01

    A transparent, elastomeric, grafted matrix for several potential applications was synthesized by single-step simultaneous radiation grafting of methacrylic acid onto ethylene vinyl acetate (EVA). CuSO4 was found to be the most suitable homo-polymerization inhibitor among different inhibitors tried. The grafting kinetics was found to be a strong function of dose rate (D) and monomer content (M) and an equation relating grafting rate Rg=Kg [M]1.13D0.23 was deduced. Crystallinity of the grafted matrices as assessed from XRD and DSC measurements indicated decrease in crystalline content with increase in grafting yield, suggesting crystalline domain of EVA get disrupted on grafting. Elastic modulus increased linearly with the increase in grafting yield, though elongation at break decreased precipitously from 900% to 30% at even 9% grafting. Thermo-gravimetric analysis showed three step weight loss of the grafted EVA matrix. The grafting of MAA resulted in increase in surface energy mainly due to enhanced polar component.

  5. Local Burn Injury Promotes Defects in the Epidermal Lipid and Antimicrobial Peptide Barriers in Human Autograft Skin and Burn Margin: Implications for Burn Wound Healing and Graft Survival

    PubMed Central

    Plichta, Jennifer K.; Holmes, Casey J.; Gamelli, Richard L.; Radek, Katherine A.

    2016-01-01

    Burn injury increases the risk of morbidity and mortality by promoting severe hemodynamic shock and risk for local or systemic infection. Graft failure due to poor wound healing or infection remains a significant problem for burn subjects. The mechanisms by which local burn injury compromises the epithelial antimicrobial barrier function in the burn margin, containing the elements necessary for healing of the burn site, and in distal unburned skin, which serves as potential donor tissue, are largely unknown. The objective of this study was to establish defects in epidermal barrier function in human donor skin and burn margin, in order to identify potential mechanisms that may lead to graft failure and/or impaired burn wound healing. In the present study, we established that epidermal lipids and respective lipid synthesis enzymes were significantly reduced in both donor skin and burn margin. We further identified diverse changes in the gene expression and protein production of several candidate skin antimicrobial peptides (AMPs) in both donor skin and burn margin. These results also parallel changes in cutaneous AMP activity against common burn wound pathogens, aberrant production of epidermal proteases known to regulate barrier permeability and AMP activity, and greater production of pro-inflammatory cytokines known to be induced by AMPs. These findings suggest that impaired epidermal lipid and AMP regulation could contribute to graft failure and infectious complications in subjects with burn or other traumatic injury. PMID:27183442

  6. Prospective Randomized Controlled Trial of Hindfoot and Ankle Fusions Treated With rhPDGF-BB in Combination With a β-TCP-Collagen Matrix.

    PubMed

    Daniels, Timothy R; Younger, Alastair S E; Penner, Murray J; Wing, Kevin J; Le, Ian L D; Russell, Iain S; Lalonde, Karl-André; Evangelista, Peter T; Quiton, Jovelyn D; Glazebrook, Mark; DiGiovanni, Christopher W

    2015-07-01

    had 2 bone graft harvest infections. Application of rhPDGF-BB/β-TCP-collagen was a safe, effective alternative to autograft for ankle and hindfoot fusions, eliminating the pain and morbidity associated with autograft harvesting. Level I, prospective randomized study. © The Author(s) 2015.

  7. Surgical Outcomes of Porcine Acellular Dermis Graft in Anophthalmic Socket: Comparison with Oral Mucosa Graft.

    PubMed

    Teo, Livia; Woo, Young Jun; Kim, Dong Kyu; Kim, Chang Yeom; Yoon, Jin Sook

    2017-02-01

    We describe our experience with the Permacol graft in anophthalmic socket reconstruction, and compare it to the autologous buccal mucosal graft, emphasizing the postoperative vascularization and contraction of each graft. This was a retrospective comparative study. We measured the time necessary for the graft surface to be completely vascularized, as well as the fornix depth of the conjunctival sac in anophthalmic patients. Ten patients underwent Permacol graft reconstruction, with 44 undergoing buccal mucosal graft reconstruction. Seven eyelids (70%) in the Permacol group had a good outcome, with improvement in lower eyelid position and prosthesis retention. Nine out of 10 eyelids (90%) in this group showed complete vascularization of the graft at 2.6 ± 1.9 months postoperatively, while the grafted buccal mucosa was fully vascularized at 1.1 ± 0.3 months postoperatively ( p < 0.01). Postoperative fornix depth in the Permacol group was 9.1 ± 2.2 mm, compared to 14.9 ± 4.5 mm in the buccal mucosal graft group ( p < 0.01). Mean increases in fornix depth were 33.1% and 67.9% of the mean vertical length of the implanted graft. The Permacol graft can be useful as spacer graft material in anophthalmic socket patients. It takes longer to vascularize, and undergoes greater graft shrinkage with time, compared to the buccal mucosal graft.

  8. Hydrodynamic radius fluctuations in model DNA-grafted nanoparticles

    NASA Astrophysics Data System (ADS)

    Vargas-Lara, Fernando; Starr, Francis W.; Douglas, Jack F.

    2016-05-01

    We utilize molecular dynamics simulations (MD) and the path-integration program ZENO to quantify hydrodynamic radius (Rh) fluctuations of spherical symmetric gold nanoparticles (NPs) decorated with single-stranded DNA chains (ssDNA). These results are relevant to understanding fluctuation-induced interactions among these NPs and macromolecules such as proteins. In particular, we explore the effect of varying the ssDNA-grafted NPs structural parameters, such as the chain length (L), chain persistence length (lp), NP core size (R), and the number of chains (N) attached to the nanoparticle core. We determine Rh fluctuations by calculating its standard deviation (σRh) of an ensemble of ssDNA-grafted NPs configurations generated by MD. For the parameter space explored in this manuscript, σR h shows a peak value as a function of N, the amplitude of which depends on L, lp and R, while the broadness depends on R.

  9. Impact of top end anastomosis design on patency and flow stability in coronary artery bypass grafting.

    PubMed

    Koyama, Sachi; Kitamura, Tadashi; Itatani, Keiichi; Yamamoto, Tadashi; Miyazaki, Shohei; Oka, Norihiko; Nakashima, Kouki; Horai, Tetsuya; Ono, Minoru; Miyaji, Kagami

    2016-05-01

    For coronary artery bypass grafting (CABG), free grafts such as a saphenous vein or radial artery are often used for grafts to the lateral and posterior walls. However, the relationship between top-end anastomosis design and long-term patency remains unknown. Because coronary artery blood flow is dominant during diastole, top-end anastomosis may work better if the graft is directed towards the apex, whereas the shortest graft pathway appears to be most efficient. Using computational fluid dynamic models, we evaluated the hemodynamic variables that were affected by the angle of the top-end anastomosis. We created three-dimensional geometries of the aortic root with coronary arteries that involved 75 % stenosis in the obtuse marginal and postero-lateral branches. Two bypass models under vasodilator administration were created: in a"Model A", the top-end anastomosis is parallel to the long axis of the ascending aorta and the graft passed over the conus directed towards the apex; in a "Model B", the top-end anastomosis is directed toward the shortest pathway, and form near the right angles to the long axis of the ascending aorta. Wall shear stress (WSS) and its fluctuation, an oscillatory shear index (OSI) were evaluated to predict fibrosis progression at the anastomosis site and graft flow. Graft flow was 197.3 ml/min and 207.3 ml/min in the "Model A" and "Model B", respectively. The minimal WSS value inside the graft with the "Model A" and "Model B" was 0.53 Pa and 4.09 Pa, respectively, and the OSI value was 0.46 and 0.04, respectively. The top-end anastomosis of a free graft should be directed vertically towards the aorta to achieve the shortest graft pathway to maintain a high graft flow rate and to avoid the risks of endothelial fibrosis and plaque progression over the long-term after CABG.

  10. In vivo outcomes of tissue-engineered osteochondral grafts.

    PubMed

    Bal, B Sonny; Rahaman, Mohamed N; Jayabalan, Prakash; Kuroki, Keiichi; Cockrell, Mary K; Yao, Jian Q; Cook, James L

    2010-04-01

    Tissue-engineered osteochondral grafts have been synthesized from a variety of materials, with some success at repairing chondral defects in animal models. We hypothesized that in tissue-engineered osteochondral grafts synthesized by bonding mesenchymal stem cell-loaded hydrogels to a porous material, the choice of the porous scaffold would affect graft healing to host bone, and the quality of cell restoration at the hyaline cartilage surface. Bone marrow-derived allogeneic mesenchymal stem cells were suspended in hydrogels that were attached to cylinders of porous tantalum metal, allograft bone, or a bioactive glass. The tissue-engineered osteochondral grafts, thus created were implanted into experimental defects in rabbit knees. Subchondral bone restoration, defect fill, bone ingrowth-implant integration, and articular tissue quality were compared between the three subchondral materials at 6 and 12 weeks. Bioactive glass and porous tantalum were superior to bone allograft in integrating to adjacent host bone, regenerating hyaline-like tissue at the graft surface, and expressing type II collagen in the articular cartilage.

  11. Epoxy and Silicone Optical Nanocomposites Filled with Grafted Nanoparticles

    NASA Astrophysics Data System (ADS)

    Tao, Peng

    , the grafted PGMA brushes effectively screen the van der Waals attraction between the particles, and homogenous nanoparticle dispersions of grafted nanoparticles were obtained. Transparent high refractive index TiO2/epoxy thin film and bulk nancomposites were obtained by dispersing PGMA brushes-grafted TiO2 nanoparticles into a commercial epoxy matrix. The refractive index of the nanocomposites showed a linear dependence on the volume fraction of TiO2 nanoparticles and the optical transparency could be generally described by the Rayleigh scattering model. This powerful dispersing technique was further employed to make visibly transparent, UV/IR blocking ITO/epoxy nanocomposites which can be easily applied onto glass and plastic substrates as energy saving optical coating materials. To produce transparent silicone nanocomposites, we directly coupled phosphate-terminated PDMS chains onto the optical nanoparticle surface. It was observed that the mono-modal PDMS-grafted particles usually formed agglomerates within silicone matrices, whereas the bimodal PDMS-grafted particles were able to be individually dispersed even within high molecular weight matrices. Transparent high refractive index bulk TiO2/silicone nanocomposites were successfully prepared by filling with bimodal PDMS-grafted TiO2 nanoparticles. Furthermore, we used the PDMS-grafted TiO2/silicone nanocomposite as a model system to create a methodology to predict and control the dispersion behavior of grafted nanoparticles. The good agreement between experimental observation of dispersion of mono-modal and bimodal grafted particles and theoretical prediction would better guide future experiments and lead to predictability in polymer composite design. Finally, the bimodal grafted chain design was implemented in the preparation of transparent and luminescent CdSe/silicone nanocomposites with potential application as non-scattering light conversion materials for LEDs. The homogeneous dispersion of bimodal PDMS-grafted

  12. Age-Dependent Risk of Graft Failure in Young Kidney Transplant Recipients.

    PubMed

    Kaboré, Rémi; Couchoud, Cécile; Macher, Marie-Alice; Salomon, Rémi; Ranchin, Bruno; Lahoche, Annie; Roussey-Kesler, Gwenaelle; Garaix, Florentine; Decramer, Stéphane; Pietrement, Christine; Lassalle, Mathilde; Baudouin, Véronique; Cochat, Pierre; Niaudet, Patrick; Joly, Pierre; Leffondré, Karen; Harambat, Jérôme

    2017-06-01

    The risk of graft failure in young kidney transplant recipients has been found to increase during adolescence and early adulthood. However, this question has not been addressed outside the United States so far. Our objective was to investigate whether the hazard of graft failure also increases during this age period in France irrespective of age at transplantation. Data of all first kidney transplantation performed before 30 years of age between 1993 and 2012 were extracted from the French kidney transplant database. The hazard of graft failure was estimated at each current age using a 2-stage modelling approach that accounted for both age at transplantation and time since transplantation. Hazard ratios comparing the risk of graft failure during adolescence or early adulthood to other periods were estimated from time-dependent Cox models. A total of 5983 renal transplant recipients were included. The risk of graft failure was found to increase around the age of 13 years until the age of 21 years, and decrease thereafter. Results from the Cox model indicated that the hazard of graft failure during the age period 13 to 23 years was almost twice as high as than during the age period 0 to 12 years, and 25% higher than after 23 years. Among first kidney transplant recipients younger than 30 years in France, those currently in adolescence or early adulthood have the highest risk of graft failure.

  13. Custom-made composite scaffolds for segmental defect repair in long bones.

    PubMed

    Reichert, Johannes C; Wullschleger, Martin E; Cipitria, Amaia; Lienau, Jasmin; Cheng, Tan K; Schütz, Michael A; Duda, Georg N; Nöth, Ulrich; Eulert, Jochen; Hutmacher, Dietmar W

    2011-08-01

    Current approaches for segmental bone defect reconstruction are restricted to autografts and allografts which possess osteoconductive, osteoinductive and osteogenic properties, but face significant disadvantages. The objective of this study was to compare the regenerative potential of scaffolds with different material composition but similar mechanical properties to autologous bone graft from the iliac crest in an ovine segmental defect model. After 12 weeks, in vivo specimens were analysed by X-ray imaging, torsion testing, micro-computed tomography and histology to assess amount, strength and structure of the newly formed bone. The highest amounts of bone neoformation with highest torsional moment values were observed in the autograft group and the lowest in the medical grade polycaprolactone and tricalcium phosphate composite group. The study results suggest that scaffolds based on aliphatic polyesters and ceramics, which are considered biologically inactive materials, induce only limited new bone formation but could be an equivalent alternative to autologous bone when combined with a biologically active stimulus such as bone morphogenetic proteins.

  14. A Canine Model of Chronic Graft-versus-Host Disease.

    PubMed

    Graves, Scott S; Rezvani, Andrew; Sale, George; Stone, Diane; Parker, Maura; Rosinski, Steven; Spector, Michele; Swearingen, Bruce; Kean, Leslie; Storb, Rainer

    2017-03-01

    In long-term survivors of allogeneic hematopoietic cell transplantation (HCT), chronic graft-versus-host disease (GVHD) is the major cause of morbidity and mortality and a major determinant of quality of life. Chronic GVHD responds poorly to current immunosuppressive drugs, and while T cell depletion may be preventive, this gain is offset by increased relapse rates. A significant impediment to progress in treating chronic GVHD has been the limitations of existing animal models. The goal of this study was to develop a reproducible comprehensive model of chronic GVHD in the dog. Ten recipient dogs received 920 cGy total body irradiation, infusion of marrow, and an infusion of buffy coat cells from a dog leukocyte antigen (DLA)-mismatched unrelated donor. Postgrafting immunosuppression consisted of methotrexate (days 1, 3, 6, 11) and cyclosporine. The duration of cyclosporine administration was limited to 80 days instead of the clinically used 180 days. This was done to contain costs, as chronic GVHD was expected to develop at earlier time points. All recipients were given ursodiol for liver protection. One dog had graft failure and 9 dogs showed stable engraftment. Eight of the 9 developed de novo chronic GVHD. Dogs progressed with clinical signs of chronic GVHD over a period of 43 to 164 (median, 88) days after discontinuation of cyclosporine. Target organs showed the spectrum of chronic GVHD manifestations that are typically seen clinically. These included lichenoid changes of the skin, fasciitis, ocular involvement (xerophthalmia), conjunctivitis, bronchiolitis obliterans, salivary gland involvement, gingivitis, esophageal involvement, and hepatic involvement. Peripheral blood lymphocyte surface antigen expression of CD28 and inducible costimulator was elevated in dogs with GHVD compared with those in normal dogs, but not significantly so. Serum levels of IL-8 and monocyte chemotactic protein-1 in GVHD-affected dogs at time of euthanasia were elevated, whereas

  15. Graft union formation in artichoke grafting onto wild and cultivated cardoon: an anatomical study.

    PubMed

    Trinchera, Alessandra; Pandozy, Gianmarco; Rinaldi, Simona; Crinò, Paola; Temperini, Olindo; Rea, Elvira

    2013-12-15

    In order to develop a non-chemical method such as grafting effective against well-known artichoke soil borne diseases, an anatomical study of union formation in artichoke grafted onto selected wild and cultivated cardoon rootstocks, both resistant to Verticillium wilt, was performed. The cardoon accessions Belgio (cultivated cardoon) and Sardo (wild cardoon) were selected as rootstocks for grafting combinations with the artichoke cv. Romolo. Grafting experiments were carried out in the autumn and spring. The anatomical investigation of grafting union formation was conducted by scanning electron microscopy (SEM) on the grafting portions at the 3rd, 6th, 10th, 12th day after grafting. For the autumn experiment only, SEM analysis was also performed at 30 d after grafting. A high affinity between artichoke scion and cardoon rootstocks was observed, with some genotype differences in healing time between the two bionts. SEM images of scion/rootstock longitudinal sections revealed the appearance of many interconnecting structures between the two grafting components just 3d after grafting, followed by a vascular rearrangement and a callus development during graft union formation. De novo formation of many plasmodesmata between scion and rootstock confirmed their high compatibility, particularly in the globe artichoke/wild cardoon combination. Moreover, the duration of the early-stage grafting process could be influenced not only by the scion/rootstock compatibility, but also by the seasonal conditions, being favored by lower temperatures and a reduced light/dark photoperiod. Copyright © 2013 Elsevier GmbH. All rights reserved.

  16. Stabilization of surface-immobilized enzymes using grafted polymers

    NASA Astrophysics Data System (ADS)

    Moskovitz, Yevgeny; Srebnik, Simcha

    2004-03-01

    Vast research efforts focus on improving the biocompatibility and biofunctionality of surfaces for artificial implants and organs. A relatively successful approach involves grafting of polymer (usually PEG) on the artificial surface, which significantly improves its biocompatibility. In addition, positioning enzymes on or in the vicinity of the surface can significantly enhance bioseparation processes. However, the catalytic activity of the anchored enzyme is often drastically impaired by the nonnatural environment, leading to loss of activity and denaturation. We study protein adsorption and stabilization by grafted polymers using a mean-field lattice model. The model protein is designed as a compact HP with a specific bulk conformation reproducing a catalytic cleft of natural enzymes. Using hydrophilic grafted polymers of tailored length and density, we show that the conformation as well as hydrophobic and active centers of the model enzyme can be restored. This research is inspired by the problem of biocompatibility and biofunctionality of surfaces for artificial implants and organs.

  17. Posttraumatic growth in post-surgical coronary artery bypass graft patients

    PubMed Central

    Waight, Catherine A; Sheridan, Judith; Tesar, Peter

    2015-01-01

    Recent research in posttraumatic growth has been applied to people with life-threatening illnesses to optimise recovery. There is a lack of research exploring posttraumatic growth in coronary artery bypass graft patients. This article describes the recovery experience of 14 coronary artery bypass graft patients (13 males and 1 female) at their first outpatient review post-surgery. Grounded theory analysis was used to develop a model of distinct and shared pathways to growth depending on whether patients were symptomatic or asymptomatic pre-coronary artery bypass graft. Outcomes of posttraumatic growth in this sample included action-based healthy lifestyle growth and two forms of cognitive growth: appreciation of life and new possibilities. The model of posttraumatic growth developed in this study may be helpful in guiding future research into promoting posttraumatic growth and behaviour change in coronary artery bypass graft patients. PMID:28070351

  18. Predictors of early graft failure after coronary artery bypass grafting for chronic total occlusion.

    PubMed

    Oshima, Hideki; Tokuda, Yoshiyuki; Araki, Yoshimori; Ishii, Hideki; Murohara, Toyoaki; Ozaki, Yukio; Usui, Akihiko

    2016-07-01

    Little is known regarding the transit-time flow measurement (TTFM) variables in grafts anastomosed to chronically totally occluded vessels (CTOs). We aimed to establish the TTFM cut-off values for detecting graft failure in bypass grafts anastomosed to chronically totally occluded arteries and clarify the relationship between early graft failure and the grade of collateral circulation/regional wall motion of the CTO territory. Among 491 patients who underwent isolated coronary artery bypass grafting (CABG) from 2009 to 2015, 196 cases with CTOs underwent postoperative coronary angiography within 1 month after CABG. Two hundred and forty-one CTOs in all patients were examined. Thirty-two CTOs (13%) were not bypassed and 214 conduits were anastomosed to CTOs and underwent intraoperative TTFM. Arterial conduits and saphenous vein grafts (SVGs) were used in 102 and 112 cases, respectively. Among the arterial conduit procedures that were performed, 78 involved the left internal thoracic artery (LITA), 10 involved the right internal thoracic artery (RITA) and 14 involved the right gastroepiploic artery (rGEA). Any graft showing Fitzgibbon type B or O lesions on angiography was considered to be a failing graft. The insufficiency rates for LITA, RITA, rGEA and SVG procedures were 5.1, 10, 14.3 and 7.1%, respectively. The TTFM variables recorded in failing grafts had a significantly lower mean flow (Qmean) and higher pulsatility index (PI) compared with patent grafts. Furthermore, akinetic or dyskinetic wall motion in the territory of bypassed CTOs was observed at a significantly higher rate in failing grafts. A multivariable regression analysis and receiver operating characteristic analysis revealed good predictors of early graft failure as follows: a Qmean value of < 11.5 ml/min for arterial conduits, a PI value of >5.85 and akinetic/dyskinetic wall motion in the CTO territory for SVGs. The Rentrop collateral grade was not associated with early graft failure. The Qmean

  19. Future Economics of Liver Transplantation: A 20-Year Cost Modeling Forecast and the Prospect of Bioengineering Autologous Liver Grafts

    PubMed Central

    Habka, Dany; Mann, David; Landes, Ronald; Soto-Gutierrez, Alejandro

    2015-01-01

    During the past 20 years liver transplantation has become the definitive treatment for most severe types of liver failure and hepatocellular carcinoma, in both children and adults. In the U.S., roughly 16,000 individuals are on the liver transplant waiting list. Only 38% of them will receive a transplant due to the organ shortage. This paper explores another option: bioengineering an autologous liver graft. We developed a 20-year model projecting future demand for liver transplants, along with costs based on current technology. We compared these cost projections against projected costs to bioengineer autologous liver grafts. The model was divided into: 1) the epidemiology model forecasting the number of wait-listed patients, operated patients and postoperative patients; and 2) the treatment model forecasting costs (pre-transplant-related costs; transplant (admission)-related costs; and 10-year post-transplant-related costs) during the simulation period. The patient population was categorized using the Model for End-Stage Liver Disease score. The number of patients on the waiting list was projected to increase 23% over 20 years while the weighted average treatment costs in the pre-liver transplantation phase were forecast to increase 83% in Year 20. Projected demand for livers will increase 10% in 10 years and 23% in 20 years. Total costs of liver transplantation are forecast to increase 33% in 10 years and 81% in 20 years. By comparison, the projected cost to bioengineer autologous liver grafts is $9.7M based on current catalog prices for iPS-derived liver cells. The model projects a persistent increase in need and cost of donor livers over the next 20 years that’s constrained by a limited supply of donor livers. The number of patients who die while on the waiting list will reflect this ever-growing disparity. Currently, bioengineering autologous liver grafts is cost prohibitive. However, costs will decline rapidly with the introduction of new manufacturing

  20. Future Economics of Liver Transplantation: A 20-Year Cost Modeling Forecast and the Prospect of Bioengineering Autologous Liver Grafts.

    PubMed

    Habka, Dany; Mann, David; Landes, Ronald; Soto-Gutierrez, Alejandro

    2015-01-01

    During the past 20 years liver transplantation has become the definitive treatment for most severe types of liver failure and hepatocellular carcinoma, in both children and adults. In the U.S., roughly 16,000 individuals are on the liver transplant waiting list. Only 38% of them will receive a transplant due to the organ shortage. This paper explores another option: bioengineering an autologous liver graft. We developed a 20-year model projecting future demand for liver transplants, along with costs based on current technology. We compared these cost projections against projected costs to bioengineer autologous liver grafts. The model was divided into: 1) the epidemiology model forecasting the number of wait-listed patients, operated patients and postoperative patients; and 2) the treatment model forecasting costs (pre-transplant-related costs; transplant (admission)-related costs; and 10-year post-transplant-related costs) during the simulation period. The patient population was categorized using the Model for End-Stage Liver Disease score. The number of patients on the waiting list was projected to increase 23% over 20 years while the weighted average treatment costs in the pre-liver transplantation phase were forecast to increase 83% in Year 20. Projected demand for livers will increase 10% in 10 years and 23% in 20 years. Total costs of liver transplantation are forecast to increase 33% in 10 years and 81% in 20 years. By comparison, the projected cost to bioengineer autologous liver grafts is $9.7M based on current catalog prices for iPS-derived liver cells. The model projects a persistent increase in need and cost of donor livers over the next 20 years that's constrained by a limited supply of donor livers. The number of patients who die while on the waiting list will reflect this ever-growing disparity. Currently, bioengineering autologous liver grafts is cost prohibitive. However, costs will decline rapidly with the introduction of new manufacturing

  1. [Advances in research and application of beta-tricalcium phosphate, collagen and beta-tricalcium phosphate/collagen composite in bone tissue engineering].

    PubMed

    Han, Xiang-Yong; Fu, Yuan-Fei; Zhang, Fu-Qiang

    2007-02-01

    Bone defects in oral and maxillofacial region was a common problem. To repair the defect, bone grafts including autograft, allograft and artificial bone graft were used in clinic despite of their disadvantages. Nowadays, bone tissue engineering has become a commonly used method to repair bone defect. This paper reviewed the application of beta-TCP, collagen and beta-TCP/collagen composite in bone tissue engineering. It was concluded that beta-TCP/collagen composite was a promising materials in bone tissue engineering.

  2. New therapeutic possibilities for vein graft disease in the post-edifoligide era.

    PubMed

    Cai, Xinjiang; Freedman, Neil J

    2006-07-01

    Vein graft neointimal hyperplasia involves proliferation and migration of vascular smooth muscle cells into the vessel intima, and ultimately engenders accelerated atherosclerosis and vein graft failure. Since a myriad of stimuli provoke smooth muscle cell proliferation, molecular therapies for vein graft disease have targeted mechanisms fundamental to all cell proliferation - the 'cell-cycle' machinery. Preclinically, the most successful of these therapies has been edifoligide (E2F decoy), a double-stranded oligodeoxynucleotide that binds to the transcription factor known as E2F. Recently, PRoject of Ex vivo vein GRaft Engineering via Transfection (PREVENT) III and IV demonstrated that edifoligide failed to benefit human vein grafts employed to treat lower-extremity ischemia and coronary heart disease, respectively. The clinical failure of edifoligide calls into question previous models of vein graft disease and lends credence to recent animal studies demonstrating that vein graft arterialization substantially involves the immigration into the vein graft of a variety of vascular progenitor cells. Future vein graft disease therapies will likely target not only proliferation of graft-intrinsic cells, but also immigration of graft-extrinsic cells.

  3. Percutaneous coronary intervention strategies and prognosis for graft lesions following coronary artery bypass grafting

    PubMed Central

    LIU, YIN; ZHOU, XIUJUN; JIANG, HUA; GAO, MINGDONG; WANG, LIN; SHI, YUTIAN; GAO, JING

    2015-01-01

    The purpose of this study was to compare the prognosis of graft-percutaneous coronary intervention (PCI) and native vessel (NV)-PCI, drug-eluting stents (DESs) and bare-metal stents (BMSs) for the treatment of graft lesions following coronary artery bypass grafting (CABG), and to determine the risk factors for major adverse cardiac events (MACEs). A total of 289 patients who underwent PCI following CABG between August 2005 and March 2010 were retrospectively analyzed. The effects on survival were compared among patients who underwent NV- and graft-PCI, and DES and BMS implantation. Additionally, the risk factors for MACEs following PCI for graft lesions were analyzed. The findings showed that MACE-free and revascularization-free survival rates were significantly higher in the NV-PCI group compared with those in the graft-PCI group. There were 63 cases (29.0%) of MACEs in the DES group and 25 cases (52.1%) in the BMS group. In patients undergoing NV-PCI, the DES group had significantly fewer MACEs and less target vessel revascularization (TVR) than the BMS group. In patients undergoing graft-PCI, the DES group showed a tendency for fewer MACEs and a lower incidence of cardiac mortality, myocardial infarction and TVR compared with the BMS group. Diabetes, an age of >70 years and graft-PCI were independent risk factors for MACEs in patients post-PCI. It is concluded that NV-PCI has superior long-term outcomes compared with graft-PCI, and should therefore be considered as the first-line treatment for graft disease following CABG. Despite this, graft-PCI remains a viable option. DESs are the first choice for graft-PCI due to their safety and efficacy and their association with reduced mortality and MACE rate. Diabetes, older age and graft-PCI are independent risk factors for MACEs in patients post-CABG who are undergoing revascularization. PMID:26136874

  4. Treatment of localized gingival recession using the free rotated papilla autograft combined with coronally advanced flap by conventional (macrosurgery) and surgery under magnification (microsurgical) technique: A comparative clinical study

    PubMed Central

    Pandey, Suraj; Mehta, D. S.

    2013-01-01

    Background: The aim of the present study was to evaluate and compare the conventional (macro-surgical) and microsurgical approach in performing the free rotated papilla autograft combined with coronally advanced flap surgery in treatment of localized gingival recession. Materials and Methods: A total of 20 sites from 10 systemically healthy patients were selected for the study. The selected sites were randomly divided into experimental site A and experimental site B by using the spilt mouth design. Conventional (macro-surgical) approach for site A and micro-surgery for site B was applied in performing the free rotated papilla autograft combined with coronally advanced flap. Recession depth (RD), recession width (RW) clinical attachment level (CAL.) and width of keratinized tissue (WKT.) were recorded at baseline, 3 months and 6 months post-operatively. Results: Both (macro- and microsurgery) groups showed significant clinical improvement in all the parameters (RD, RW, CAL and WKT). However, on comparing both the groups, these parameters did not reach statistical significance. Conclusion: Both the surgical procedures were equally effective in treatment of localized gingival recession by the free rotated papilla autograft technique combined with coronally advanced flap. However, surgery under magnification (microsurgery) may be clinically better than conventional surgery in terms of less post-operative pain and discomfort experienced by patients at the microsurgical site. PMID:24554888

  5. Compression and contact area of anterior strut grafts in spinal instrumentation: a biomechanical study.

    PubMed

    Pizanis, Antonius; Holstein, Jörg H; Vossen, Felix; Burkhardt, Markus; Pohlemann, Tim

    2013-08-26

    Anterior bone grafts are used as struts to reconstruct the anterior column of the spine in kyphosis or following injury. An incomplete fusion can lead to later correction losses and compromise further healing. Despite the different stabilizing techniques that have evolved, from posterior or anterior fixating implants to combined anterior/posterior instrumentation, graft pseudarthrosis rates remain an important concern. Furthermore, the need for additional anterior implant fixation is still controversial. In this bench-top study, we focused on the graft-bone interface under various conditions, using two simulated spinal injury models and common surgical fixation techniques to investigate the effect of implant-mediated compression and contact on the anterior graft. Calf spines were stabilised with posterior internal fixators. The wooden blocks as substitutes for strut grafts were impacted using a "pressfit" technique and pressure-sensitive films placed at the interface between the vertebral bone and the graft to record the compression force and the contact area with various stabilization techniques. Compression was achieved either with posterior internal fixator alone or with an additional anterior implant. The importance of concomitant ligament damage was also considered using two simulated injury models: pure compression Magerl/AO fracture type A or rotation/translation fracture type C models. In type A injury models, 1 mm-oversized grafts for impaction grafting provided good compression and fair contact areas that were both markedly increased by the use of additional compressing anterior rods or by shortening the posterior fixator construct. Anterior instrumentation by itself had similar effects. For type C injuries, dramatic differences were observed between the techniques, as there was a net decrease in compression and an inadequate contact on the graft occurred in this model. Under these circumstances, both compression and the contact area on graft could only

  6. Management of an infected aortic graft with endovascular stent grafting.

    PubMed

    Jamel, Sara; Attia, Rizwan; Young, Christopher

    2013-01-01

    Aortic graft infection, one of the most common fatal complications of aortovascular surgery, is managed mainly by the removal of infected graft material and re-establishment of vascular continuity using an extra-anatomical bypass or in situ graft replacement. Despite significant progress in perioperative, surgical, and medical treatments, the mortality and morbidity for this condition remain high. Here, we report the use of endograft implantation and prolonged intravenous antibiotics to successfully treat a life-threatening Dacron aortic tube graft infection and anastomotic leak. Although the gold standard is surgical removal of infected material and repair with a homograft, in certain extremely high-risk patients such as ours, an alternate strategy may be warranted when the risks associated with surgery are prohibitive. Endovascular repair of a surgical Dacron graft leak may provide a novel temporizing measure in the acute setting, allowing for delayed semi-urgent surgical intervention, or it may provide a definitive treatment, as in our case. At the four-year follow-up, our patient was well with a good quality of life and with no clinical, radiological, or biochemical evidence of infection.

  7. Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction With a Free Quadriceps Tendon Autograft.

    PubMed

    Caterev, Sergiu; Nistor, Dan Viorel; Todor, Adrian

    2016-10-01

    Anatomic double-bundle anterior cruciate ligament (ACL) reconstruction aims to restore the 2 functional bundles of the ACL in an attempt to better reproduce the native biomechanics of the injured knee and promote long-term knee health. However, this concept is not fully accepted and is not performed on a standard basis. In addition, the superiority of this technique over the conventional single-bundle technique has been questioned, especially the long-term clinical results. One of the down sides of the double-bundle reconstruction is the complexity of the procedure, with increased risks, operative time, and costs compared with the single-bundle procedure. Also, the revision procedure, if necessary, is more challenging. We propose a technique that has some advantages over the traditional double-bundle procedure, using a single femoral tunnel, 2 tibial tunnels, and a free quadriceps tendon autograft.

  8. Independent Suture Tape Reinforcement of Small and Standard Diameter Grafts for Anterior Cruciate Ligament Reconstruction: A Biomechanical Full Construct Model.

    PubMed

    Bachmaier, Samuel; Smith, Patrick A; Bley, Jordan; Wijdicks, Coen A

    2018-02-01

    To compare the dynamic elongation, stiffness behavior, and ultimate failure load of standard with small diameter soft tissue grafts for anterior cruciate ligament (ACL) reconstruction with and without high-strength suture tape reinforcement. Both a tripled "small" diameter and a "standard" quadrupled tendon graft with and without suture tape reinforcement were tested using suspensory fixation (n = 8 each group). The suture tape was passed through the suspensory fixation button on the femur and tibia to ensure independent (safety belt) fixation from the graft in vitro. The testing of the constructs included position-controlled cyclic loading, force-controlled cyclic loading at 250 N and 400 N as well as pull to failure (50 mm/min). Reinforcement of a small diameter graft significantly reduced dynamic elongation of 38% (1.46 ± 0.28 mm vs 2.34 ± 0.44 mm, P < .001) and 50% (2.55 ± 0.44 mm vs 5.06 ± 0.67 mm, P < .001) after the 250 N and 400 N load protocol, respectively. Reinforcement of a standard diameter tendon graft decreased dynamic elongation of 15% (1.59 ± 0.34 mm vs 1.86 ± 0.17 mm, P = .066) and 26% (2.62 ± 0.44 mm vs 3.55 ± 0.44 mm, P < .001). No significant difference was found between both reinforced models. The ultimate failure loads of small and standard diameter reinforced grafts were 1592 ± 105 N and 1585 ± 265 N, resulting in a 64% (P < .001) and 40% (P < .001) increase compared with their respective controls. Independent suture tape reinforcement of soft tissue grafts for ACL reconstruction leads to significantly reduced elongation and higher ultimate failure load according to in vivo native ACL function data without stress-shielding the soft tissue graft. If in vitro results are translational to human knees in vivo, the suture tape reinforcement technique for ACL reconstruction may decrease the risk of graft tears, particularly in the case of small diameter soft tissue grafts. Copyright © 2017 Arthroscopy Association of

  9. Simulation of blood flow in a small-diameter vascular graft model with a swirl (spiral) flow guider.

    PubMed

    Zhang, ZhiGuo; Fan, YuBo; Deng, XiaoYan; Wang, GuiXue; Zhang, He; Guidoin, Robert

    2008-10-01

    Small-diameter vascular grafts are in large demand for coronary and peripheral bypass procedures, but present products still fail in long-term clinical application. In the present communication, a new type of small-diameter graft with a swirl flow guider was proposed to improve graft patency rate. Flow pattern in the graft was simulated numerically and compared with that in a conventional graft. The numerical results revealed that the swirl flow guider could indeed make the blood flow rotate in the new graft. The swirling flow distal to the flow guider significantly altered the flow pattern in the new graft and the velocity profiles were re-distributed. Due to the swirling flow, the blood velocity near the vessel wall and wall shear rate were greatly enhanced. We believe that the increased blood velocity near the wall and the wall shear rate can impede the occurrence of acute thrombus formation and intimal hyperplasia, hence can improve the graft patency rate for long-term clinical use.

  10. Circulating AST, H-FABP, and NGAL are early and accurate biomarkers of graft injury and dysfunction in a preclinical model of kidney transplantation.

    PubMed

    Jochmans, Ina; Lerut, Evelyne; van Pelt, Jos; Monbaliu, Diethard; Pirenne, Jacques

    2011-11-01

    To investigate circulating biomarkers of initial graft injury in a porcine kidney autotransplant model. Injury endured by kidney grafts early posttransplant determines their outcome. However, creatinine (clearance) is a poor surrogate of tissue injury and urinary biomarkers are limited by graft anuria or persistent native kidney diuresis. No validated circulating biomarkers quantifying initial graft injury exist. Minimally injured porcine kidney grafts (n = 6) were cold stored (18 hours) and autotransplanted. Moderately (n = 6) and severely injured grafts (n = 7) were exposed to 30 or 60 minutes warm ischemia before storage and autotransplantation. Four biomarkers [aspartate transaminase (AST), heart-type fatty acid-binding protein (H-FABP), neutrophil gelatinase-associated lipocalin (NGAL), and N-acetyl-β-glucosaminidase (NAG)] were measured posttransplant and compared with creatinine (clearance) and histology. Diuresis was delayed in moderately [2.5 days (2-3)] and severely [4 days (4-5)] versus minimally injured grafts (P < 0.001). Creatinine peaked later than AST, H-FABP, and NGAL [4 days (3-5) vs 3 hours (3-6), 6 hours (6-24), 2 days (1-3), respectively] and only differentiated minimally from severely injured grafts. Peak AST and H-FABP distinguished all injury grades. Neutrophil gelatinase-associated lipocalin discriminated initial graft injury 2 days posttransplant. Peak AST, H-FABP, and NGAL correlated with peak creatinine [Pearson coefficients: 0.70 (P = 0.001), 0.85 (P < 0.0001), 0.80 (P < 0.0001)]. N-acetyl-β-glucosaminidase was not different. Decreased clearance accounted for a small percentage of H-FABP and NGAL increase. Histology was not different among transplanted groups. Plasma AST, H-FABP, and NGAL reflect the severity of initial kidney graft injury and predict graft dysfunction earlier and more accurately than creatinine (clearance) and histology. They represent promising tools to improve patient care after kidney transplantation.

  11. Association Between Delayed Graft Function and Graft Loss in Donation After Cardiac Death Kidney Transplants-A Paired Kidney Registry Analysis.

    PubMed

    Lim, Wai H; McDonald, Stephen P; Russ, Graeme R; Chapman, Jeremy R; Ma, Maggie Km; Pleass, Henry; Jaques, Bryon; Wong, Germaine

    2017-06-01

    Delayed graft function (DGF) is an established complication after donation after cardiac death (DCD) kidney transplants, but the impact of DGF on graft outcomes is uncertain. To minimize donor variability and bias, a paired donor kidney analysis was undertaken where 1 kidney developed DGF and the other did not develop DGF using data from the Australia and New Zealand Dialysis and Transplant Registry. Using paired DCD kidney data from the Australia and New Zealand Dialysis and Transplant Registry, we examined the association between DGF, graft and patient outcomes between 1994 and 2012 using adjusted Cox regression models. Of the 74 pairs of DCD kidneys followed for a median of 1.9 years (408 person-years), a greater proportion of recipients with DGF had experienced overall graft loss and death-censored graft loss at 3 years compared with those without DGF (14% vs 4%, P = 0.04 and 11% vs 0%, P < 0.01, respectively). Compared with recipients without DGF, the adjusted hazard ratio for overall graft loss at 3 years for recipients with DGF was 4.31 (95% confidence interval [95% CI], 1.13-16.44). The adjusted hazard ratio for acute rejection and all-cause mortality at 3 years in recipients who have experienced DGF were 0.98 (95% CI, 0.96-1.01) and 1.70 (95% CI, 0.36-7.93), respectively, compared with recipients without DGF. Recipients of DCD kidneys with DGF experienced a higher incidence of overall and death-censored graft loss compared with those without DGF. Strategies aim to reduce the risk of DGF could potentially improve graft survival in DCD kidney transplants.

  12. Repair of Tympanic Membrane Perforations with Customized Bioprinted Ear Grafts Using Chinchilla Models.

    PubMed

    Kuo, Che-Ying; Wilson, Emmanuel; Fuson, Andrew; Gandhi, Nidhi; Monfaredi, Reza; Jenkins, Audrey; Romero, Maria; Santoro, Marco; Fisher, John P; Cleary, Kevin; Reilly, Brian

    2018-03-01

    The goal of this work is to develop an innovative method that combines bioprinting and endoscopic imaging to repair tympanic membrane perforations (TMPs). TMPs are a serious health issue because they can lead to both conductive hearing loss and repeated otitis media. TMPs occur in 3-5% of cases after ear tube placement, as well as in cases of acute otitis media (the second most common infection in pediatrics), chronic otitis media with or without cholesteatoma, or as a result of barotrauma to the ear. About 55,000 tympanoplasties, the surgery performed to reconstruct TMPs, are performed every year, and the commonly used cartilage grafting technique has a success rate between 43% and 100%. This wide variability in successful tympanoplasty indicates that the current approach relies heavily on the skill of the surgeon to carve the shield graft into the shape of the TMP, which can be extremely difficult because of the perforation's irregular shape. To this end, we hypothesized that patient specific acellular grafts can be bioprinted to repair TMPs. In vitro data demonstrated that our approach resulted in excellent wound healing responses (e.g., cell invasion and proliferations) using our bioprinted gelatin methacrylate constructs. Based on these results, we then bioprinted customized acellular grafts to treat TMP based on endoscopic imaging of the perforation and demonstrated improved TMP healing in a chinchilla study. These ear graft techniques could transform clinical practice by eliminating the need for hand-carved grafts. To our knowledge, this is the first proof of concept of using bioprinting and endoscopic imaging to fabricate customized grafts to treat tissue perforations. This technology could be transferred to other medical pathologies and be used to rapidly scan internal organs such as intestines for microperforations, brain covering (Dura mater) for determination of sites of potential cerebrospinal fluid leaks, and vascular systems to determine arterial

  13. Diversity of gut microflora is required for the generation of B cell with regulatory properties in a skin graft model

    PubMed Central

    Alhabbab, R.; Blair, P.; Elgueta, R.; Stolarczyk, E.; Marks, E.; Becker, P. D.; Ratnasothy, K.; Smyth, L.; Safinia, N.; Sharif-Paghaleh, E.; O’Connell, S.; Noelle, R. J.; Lord, G. M.; Howard, J. K.; Spencer, J.; Lechler, R. I.; Lombardi, G.

    2015-01-01

    B cells have been reported to promote graft rejection through alloantibody production. However, there is growing evidence that B cells can contribute to the maintenance of tolerance. Here, we used a mouse model of MHC-class I mismatched skin transplantation to investigate the contribution of B cells to graft survival. We demonstrate that adoptive transfer of B cells prolongs skin graft survival but only when the B cells were isolated from mice housed in low sterility “conventional” (CV) facilities and not from mice housed in pathogen free facilities (SPF). However, prolongation of skin graft survival was lost when B cells were isolated from IL-10 deficient mice housed in CV facilities. The suppressive function of B cells isolated from mice housed in CV facilities correlated with an anti-inflammatory environment and with the presence of a different gut microflora compared to mice maintained in SPF facilities. Treatment of mice in the CV facility with antibiotics abrogated the regulatory capacity of B cells. Finally, we identified transitional B cells isolated from CV facilities as possessing the regulatory function. These findings demonstrate that B cells, and in particular transitional B cells, can promote prolongation of graft survival, a function dependent on licensing by gut microflora. PMID:26109230

  14. Self-assembly of model graft copolymers of agarose and weak polyelectrolyte-based amphiphilic diblock copolymers: controlled drug release and degradation.

    PubMed

    Muppalla, Ravikumar; Jewrajka, Suresh K; Prasad, Kamalesh

    2013-06-01

    Polysaccharide-based copolymers are promising biomaterials due to their biocompatibility and biodegradability. For potential biomedical applications the copolymer as a whole and all the degraded species must be biocompatible and easily removable from the system. In this regards, new model pH-responsive seaweed agarose (Agr) grafted with weak polyelectrolyte-based well-defined amphiphilic block copolymers ca. poly[(methyl methacrylate)-b-(2-dimethylamino)ethyl methacrylate)] (PMMA-b-PDMA) were designed and synthesized to study the self-assembly, degradation, and in vitro hydrophobic/hydrophilic drug release behavior. The graft copolymer solutions display extremely low critical micelle concentration (CMC) and form pH responsive stable micelles. The degradation study of the graft copolymer reveals that the entire degraded components are well soluble/dispersible in water due to formation of mixed micelles. The micelles are also strongly adsorbed on the mica surface owing to electrostatic interaction. One application of the graft copolymer micelles is that it can entrap both hydrophilic and poorly water soluble hydrophobic drugs effectively and exhibit slow release kinetics. The release kinetics of both the hydrophilic and poorly water soluble hydrophobic drugs change with pH as well as with the composition of the graft copolymer. Copyright © 2012 Wiley Periodicals, Inc.

  15. Reconstructive procedures for segmental resection of bone in giant cell tumors around the knee.

    PubMed

    Aggarwal, Aditya N; Jain, Anil K; Kumar, Sudhir; Dhammi, Ish K; Prashad, Bhagwat

    2007-04-01

    Segmental resection of bone in Giant Cell Tumor (GCT) around the knee, in indicated cases, leaves a gap which requires a complex reconstructive procedure. The present study analyzes various reconstructive procedures in terms of morbidity and various complications encountered. Thirteen cases (M-six and F-seven; lower end femur-six and upper end tibia -seven) of GCT around the knee, radiologically either Campanacci Grade II, Grade II with pathological fracture or Grade III were included. Mean age was 25.6 years (range 19-30 years). Resection arthrodesis with telescoping (shortening) over intramedullary nail (n=5), resection arthrodesis with an intercalary allograft threaded over a long intramedullary nail (n=3) and resection arthrodesis with intercalary fibular autograft and simultaneous limb lengthening (n=5) were the procedure performed. Shortening was the major problem following resection arthrodesis with telescoping (shortening) over intramedullary nail. Only two patients agreed for subsequent limb lengthening. The rest continued to walk with shortening. Infection was the major problem in all cases of resection arthrodesis with an intercalary allograft threaded over a long intramedullary nail and required multiple drainage procedures. Fusion was achieved after two years in two patients. In the third patient the allograft sequestrated. The patient underwent sequestrectomy, telescoping of fragments and ilizarov fixator application with subsequent limb lengthening. The patient was finally given an ischial weight relieving orthosis, 54 months after the index procedure. After resection arthrodesis with intercalary autograft and simultaneous lengthening the resultant gap (∼15cm) was partially bridged by intercalary nonvascularized dual fibular strut graft (6-7cm) and additional corticocancellous bone graft from ipsilateral patella. Simultaneous limb lengthening with a distal tibial corticotomy was performed on an ilizarov fixator. The complications were superficial

  16. Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti-Inflammatory Agents

    DTIC Science & Technology

    2017-10-01

    factor in the development of skin graft contraction. Using a porcine model of skin graft contraction, we will screen for anti- inflammatory agents (dose...Award Number: W81XWH-14-2-0153 TITLE: Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti-Inflammatory Agents ...09/14/2017 4. TITLE AND SUBTITLE “Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti-Inflammatory Agents ” 5a

  17. Magnetizable stent-grafts enable endothelial cell capture

    NASA Astrophysics Data System (ADS)

    Tefft, Brandon J.; Uthamaraj, Susheil; Harburn, J. Jonathan; Hlinomaz, Ota; Lerman, Amir; Dragomir-Daescu, Dan; Sandhu, Gurpreet S.

    2017-04-01

    Emerging nanotechnologies have enabled the use of magnetic forces to guide the movement of magnetically-labeled cells, drugs, and other therapeutic agents. Endothelial cells labeled with superparamagnetic iron oxide nanoparticles (SPION) have previously been captured on the surface of magnetizable 2205 duplex stainless steel stents in a porcine coronary implantation model. Recently, we have coated these stents with electrospun polyurethane nanofibers to fabricate prototype stent-grafts. Facilitated endothelialization may help improve the healing of arteries treated with stent-grafts, reduce the risk of thrombosis and restenosis, and enable small-caliber applications. When placed in a SPION-labeled endothelial cell suspension in the presence of an external magnetic field, magnetized stent-grafts successfully captured cells to the surface regions adjacent to the stent struts. Implantation within the coronary circulation of pigs (n=13) followed immediately by SPION-labeled autologous endothelial cell delivery resulted in widely patent devices with a thin, uniform neointima and no signs of thrombosis or inflammation at 7 days. Furthermore, the magnetized stent-grafts successfully captured and retained SPION-labeled endothelial cells to select regions adjacent to stent struts and between stent struts, whereas the non-magnetized control stent-grafts did not. Early results with these prototype devices are encouraging and further refinements will be necessary in order to achieve more uniform cell capture and complete endothelialization. Once optimized, this approach may lead to more rapid and complete healing of vascular stent-grafts with a concomitant improvement in long-term device performance.

  18. Magnetizable stent-grafts enable endothelial cell capture.

    PubMed

    Tefft, Brandon J; Uthamaraj, Susheil; Harburn, J Jonathan; Hlinomaz, Ota; Lerman, Amir; Dragomir-Daescu, Dan; Sandhu, Gurpreet S

    2017-04-01

    Emerging nanotechnologies have enabled the use of magnetic forces to guide the movement of magnetically-labeled cells, drugs, and other therapeutic agents. Endothelial cells labeled with superparamagnetic iron oxide nanoparticles (SPION) have previously been captured on the surface of magnetizable 2205 duplex stainless steel stents in a porcine coronary implantation model. Recently, we have coated these stents with electrospun polyurethane nanofibers to fabricate prototype stent-grafts. Facilitated endothelialization may help improve the healing of arteries treated with stent-grafts, reduce the risk of thrombosis and restenosis, and enable small-caliber applications. When placed in a SPION-labeled endothelial cell suspension in the presence of an external magnetic field, magnetized stent-grafts successfully captured cells to the surface regions adjacent to the stent struts. Implantation within the coronary circulation of pigs (n=13) followed immediately by SPION-labeled autologous endothelial cell delivery resulted in widely patent devices with a thin, uniform neointima and no signs of thrombosis or inflammation at 7 days. Furthermore, the magnetized stent-grafts successfully captured and retained SPION-labeled endothelial cells to select regions adjacent to stent struts and between stent struts, whereas the non-magnetized control stent-grafts did not. Early results with these prototype devices are encouraging and further refinements will be necessary in order to achieve more uniform cell capture and complete endothelialization. Once optimized, this approach may lead to more rapid and complete healing of vascular stent-grafts with a concomitant improvement in long-term device performance.

  19. Cost comparative study of autologous peripheral blood progenitor cells (PBPC) and bone marrow (ABM) transplantations for non-Hodgkin's lymphoma patients.

    PubMed

    Woronoff-Lemsi, M C; Arveux, P; Limat, S; Deconinck, E; Morel, P; Cahn, J Y

    1997-12-01

    Intensive high-dose chemotherapy with autologous stem-cell support has become a common treatment strategy for non-Hodgkin's lymphomas. A cost-identification analysis was conducted comparing 10 patients autografted with PBSC to 10 others autografted with BM. The analysis included harvest and graft until graft day +100 and was carried out from the point of view of the hospital setting. Resources used, logistic and direct medical costs per patient were identified, and sensitivity analyses performed. The cost distribution was different. Stem cell harvest was more expensive for PBPC ($9030) and BM ($4745); on the other hand, hospitalization from graft to discharge from hospital cost savings with PBSC were about $10666. After discharge from hospital, costs were similar and cheaper in both groups. For the overall study the PBPC procedure was less expensive than ABMT, $35381 and $41759 respectively, with cost savings of $6378. The number of days spent in hospital and blood bank costs were the major cost factors. This study was based on a single pathology, non-Hodgkin's lymphoma, and the actual hospital records for each patient situation as opposed to a clinical trial, and our results were consistent with different previous studies carried out in different health care systems.

  20. Plant grafting: new mechanisms, evolutionary implications.

    PubMed

    Goldschmidt, Eliezer E

    2014-01-01

    Grafting, an old plant propagation practice, is still widely used with fruit trees and in recent decades also with vegetables. Taxonomic proximity is a general prerequisite for successful graft-take and long-term survival of the grafted, composite plant. However, the mechanisms underlying interspecific graft incompatibility are as yet insufficiently understood. Hormonal signals, auxin in particular, are believed to play an important role in the wound healing and vascular regeneration within the graft union zone. Incomplete and convoluted vascular connections impede the vital upward and downward whole plant transfer routes. Long-distance protein, mRNA and small RNA graft-transmissible signals currently emerge as novel mechanisms which regulate nutritional and developmental root/top relations and may play a pivotal role in grafting physiology. Grafting also has significant pathogenic projections. On one hand, stock to scion mechanical contact enables the spread of diseases, even without a complete graft union. But, on the other hand, grafting onto resistant rootstocks serves as a principal tool in the management of fruit tree plagues and vegetable soil-borne diseases. The 'graft hybrid' historic controversy has not yet been resolved. Recent evidence suggests that epigenetic modification of DNA-methylation patterns may account for certain graft-transformation phenomena. Root grafting is a wide spread natural phenomenon; both intraspecific and interspecific root grafts have been recorded. Root grafts have an evolutionary role in the survival of storm-hit forest stands as well as in the spread of devastating diseases. A more fundamental evolutionary role is hinted by recent findings that demonstrate plastid and nuclear genome transfer between distinct Nicotiana species in the graft union zone, within a tissue culture system. This has led to the formation of alloploid cells that, under laboratory conditions, gave rise to a novel, alloploid Nicotiana species, indicating

  1. Plant grafting: new mechanisms, evolutionary implications

    PubMed Central

    Goldschmidt, Eliezer E.

    2014-01-01

    Grafting, an old plant propagation practice, is still widely used with fruit trees and in recent decades also with vegetables. Taxonomic proximity is a general prerequisite for successful graft-take and long-term survival of the grafted, composite plant. However, the mechanisms underlying interspecific graft incompatibility are as yet insufficiently understood. Hormonal signals, auxin in particular, are believed to play an important role in the wound healing and vascular regeneration within the graft union zone. Incomplete and convoluted vascular connections impede the vital upward and downward whole plant transfer routes. Long-distance protein, mRNA and small RNA graft-transmissible signals currently emerge as novel mechanisms which regulate nutritional and developmental root/top relations and may play a pivotal role in grafting physiology. Grafting also has significant pathogenic projections. On one hand, stock to scion mechanical contact enables the spread of diseases, even without a complete graft union. But, on the other hand, grafting onto resistant rootstocks serves as a principal tool in the management of fruit tree plagues and vegetable soil-borne diseases. The ‘graft hybrid’ historic controversy has not yet been resolved. Recent evidence suggests that epigenetic modification of DNA-methylation patterns may account for certain graft-transformation phenomena. Root grafting is a wide spread natural phenomenon; both intraspecific and interspecific root grafts have been recorded. Root grafts have an evolutionary role in the survival of storm-hit forest stands as well as in the spread of devastating diseases. A more fundamental evolutionary role is hinted by recent findings that demonstrate plastid and nuclear genome transfer between distinct Nicotiana species in the graft union zone, within a tissue culture system. This has led to the formation of alloploid cells that, under laboratory conditions, gave rise to a novel, alloploid Nicotiana species

  2. [Aortic reconstruction with graft materials resistant to bacterial infections].

    PubMed

    Hassen-Khodja, Réda; Sadaghianloo, Nirvana; Jean-Baptiste, Élixène

    2013-01-01

    Synthetic graft infection is a rare but extremely serious complication of aortic reconstruction procedures, with morbidity-mortality rates as high as 60 %. Some of the proteins (albumin, gelatin, collagen) used to coat polyester graft materials can establish ionic bonds with antibiotics or can capture antiseptics such as triclosan or ionic silver in their matrices. These active substances are then released from the graft, at varying rates, during the coating degradation that takes place during the weeks following polyester graft implantation in living tissues. Rifampin-bonded prostheses have proved effective against S. aureus and S. epidermidis in several canine models of synthetic aortic graft infection. Rifampin-bonded grafts have also been used successfully in patients with synthetic aortic graft infection by low-virulence bacteria. However, their effectiveness may be limited by the diverse and changing ecology of synthetic aortic graft infections, with an increasing prevalence of multidrug-resistant bacteria and polymicrobial infections. These include species that are naturally, or are likely to become, resistant to rifampin. We evaluated silver-ion-bonded prostheses in this setting but observed a disappointingly high mid-term rate of recurrent infections. Over the past few years we have been involved in the development of polyester vascular prostheses functionalized with a hydroxypropyl-β-cyclodextrin polymeric matrix that can capture and elute several therapeutic agents. The results are promising, as these prostheses enable the sustained release of various antibiotics in amounts several times their minimum inhibitory concentrations. This provides a unique opportunity to functionalize materials for aortic graft reconstruction, based on epidemiological data or individual bacteriological findings.

  3. In Vitro Quantification of Gutter Formation and Chimney Graft Compression in Chimney EVAR Stent-Graft Configurations Using Electrocardiography-Gated Computed Tomography.

    PubMed

    Overeem, Simon P; Donselaar, Esmé J; Boersen, Jorrit T; Groot Jebbink, Erik; Slump, Cornelis H; de Vries, Jean-Paul P M; Reijnen, Michel M P J

    2018-03-01

    To assess the dynamic behavior of chimney grafts during the cardiac cycle. Three chimney endovascular aneurysm repair (EVAR) stent-graft configurations (Endurant and Advanta V12, Endurant and Viabahn, and Endurant and BeGraft) were placed in silicone aneurysm models and subjected to physiologic flow. Electrocardiography (ECG)-gated contrast-enhanced computed tomography was used to visualize geometric changes during the cardiac cycle. Endograft and chimney graft surface, gutter volume, chimney graft angulation over the center lumen line, and the D-ratio (the ratio between the lengths of the major and minor axes) were independently assessed by 2 observers at 10 time points in the cardiac cycle. Both gutter volumes and chimney graft geometry changed significantly during the cardiac cycle in all 3 configurations (p<0.001). Gutters and endoleaks were observed in all configurations. The largest gutter volume (232.8 mm 3 ) and change in volume (20.7 mm 3 ) between systole and diastole were observed in the Endurant-Advanta configuration. These values were 2.7- and 3.0-fold higher, respectively, compared to the Endurant-Viabahn configuration and 1.7- and 1.6-fold higher as observed in the Endurant-BeGraft configuration. The Endurant-Viabahn configuration had the highest D-ratio (right, 1.26-1.35; left, 1.33-1.48), while the Endurant-BeGraft configuration had the lowest (right, 1.11-1.17; left, 1.08-1.15). Assessment of the interobserver variability showed a high correlation (intraclass correlation >0.935) between measurements. Gutter volumes and stent compression are dynamic phenomena that reshape during the cardiac cycle. Compelling differences were observed during the cardiac cycle in all configurations, with the self-expanding (Endurant-Viabahn) chimney EVAR configurations having smaller gutters and less variation in gutter volume during the cardiac cycle yet more stent compression without affecting the chimney graft surface.

  4. Current status of grafts and implants in rhinoplasty: Part II. Homologous grafts and allogenic implants.

    PubMed

    Sajjadian, Ali; Naghshineh, Nima; Rubinstein, Roee

    2010-03-01

    After reading this article, the participant should be able to: 1. Understand the challenges in restoring volume and structural integrity in rhinoplasty. 2. Identify the appropriate uses of various homologous grafts and allogenic implants in reconstruction, including: (a) freeze-dried acellular allogenic cadaveric dermis grafts, (b) irradiated cartilage grafts, (c) hydroxyapatite mineral matrix, (d) silicone implants, (e) high-density polyethylene implants, (f) polytetrafluoroethylene implants, and (g) injectable filler materials. 3. Identify the advantages and disadvantages of each of these biomaterials. 4. Understand the specific techniques that may aid in the use these grafts or implants. This review specifically addresses the use of homologous grafts and allogenic implants in rhinoplasty. It is important to stress that autologous materials remain the preferred graft material for use in rhinoplasty, owing to their high biocompatibility and low risk of infection and extrusion. However, concerns of donor-site morbidity, graft availability, and graft resorption have motivated the development and use of homologous and allogenic implants.

  5. Radionuclide bone imaging in the evaluation of osseous allograft systems. Scientific report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kelly, J.F.; Cagle, J.D.; Stevenson, J.S.

    1975-02-01

    Evaluation of the progress of osteogenic activity in mandibular bone grafts in dogs by a noninvasive, nondestructive radionuclide method is feasible. The method provides a meaningful sequential interpretation of osseous repair more sensitive than conventional radiography. It is presumed that accumulating hydroxyapatite is being labelled by the imaging agent technetium diphosphonate. The osseous allograft systems studied were comparable to or exceeded autografts in their repair activity in mandibular discontinuity defects as judged by radionuclide imaging. A lyophilized mandibular allograft segment augmented with autologous cancellous marrow was more active than autograft controls at 3 and 6 weeks and was the mostmore » active system studied. Allograft segments augmented with lyophilized crushed cortical allogeneic bone particles were equal to controls at 3 weeks and more active than controls at 6 weeks. Lyophilized crushed cortical allogeneic bone particles retained in a Millipore filter while not clinically stable at 6 weeks did show osteogenic activity equal to control autografts at this interval. (GRA)« less

  6. Penile Inversion Vaginoplasty with or without Additional Full-Thickness Skin Graft: To Graft or Not to Graft?

    PubMed

    Buncamper, Marlon E; van der Sluis, Wouter B; de Vries, Max; Witte, Birgit I; Bouman, Mark-Bram; Mullender, Margriet G

    2017-03-01

    Penile inversion vaginoplasty is considered to be the gold standard for gender reassignment surgery in transgender women. The use of additional full-thickness skin graft as neovaginal lining is controversial. Some believe that having extra penile skin for the vulva gives better aesthetic results. Others believe that it gives inferior functional results because of insensitivity and skin graft contraction. Transgender women undergoing penile inversion vaginoplasty were studied prospectively. The option to add full-thickness skin graft is offered in patients where the penile skin length lies between 7 and 12 cm. Neovaginal depth was measured at surgery and during follow-up (3, 13, 26, and 52 weeks postoperatively). Satisfaction with the aesthetic result, neovaginal depth, and dilation regimen during follow-up were recorded. Satisfaction, sexual function, and genital self-image were assessed using questionnaires. A total of 100 patients were included (32 with and 68 without additional full-thickness skin graft). Patient-reported aesthetic outcome, overall satisfaction with the neovagina, sexual function, and genital self-image were not significantly associated with surgical technique. The mean intraoperative neovaginal depth was 13.8 ± 1.4 cm. After 1 year, this was 11.5 ± 2.5 cm. The largest decline (-15 percent) in depth is observed in the first 3 postoperative weeks (p < 0.01). The authors can confirm neither of the suggested arguments, for or against full-thickness skin graft use, in penile inversion vaginoplasty. The additional use of full-thickness skin graft does not influence neovaginal shrinkage, nor does it affect the patient- and physician-reported aesthetic or functional outcome. Therapeutic, IV.

  7. Physiologic Preoperative Knee Hyperextension Is a Predictor of Failure in an Anterior Cruciate Ligament Revision Cohort: A Report From the MARS Group.

    PubMed

    Cooper, Daniel E; Dunn, Warren R; Huston, Laura J; Haas, Amanda K; Spindler, Kurt P; Allen, Christina R; Anderson, Allen F; DeBerardino, Thomas M; Lantz, Brett Brick A; Mann, Barton; Stuart, Michael J; Albright, John P; Amendola, Annunziato Ned; Andrish, Jack T; Annunziata, Christopher C; Arciero, Robert A; Bach, Bernard R; Baker, Champ L; Bartolozzi, Arthur R; Baumgarten, Keith M; Bechler, Jeffery R; Berg, Jeffrey H; Bernas, Geoffrey A; Brockmeier, Stephen F; Brophy, Robert H; Bush-Joseph, Charles A; Butler V, J Brad; Campbell, John D; Carey, James L; Carpenter, James E; Cole, Brian J; Cooper, Jonathan M; Cox, Charles L; Creighton, R Alexander; Dahm, Diane L; David, Tal S; Flanigan, David C; Frederick, Robert W; Ganley, Theodore J; Garofoli, Elizabeth A; Gatt, Charles J; Gecha, Steven R; Giffin, James Robert; Hame, Sharon L; Hannafin, Jo A; Harner, Christopher D; Harris, Norman Lindsay; Hechtman, Keith S; Hershman, Elliott B; Hoellrich, Rudolf G; Hosea, Timothy M; Johnson, David C; Johnson, Timothy S; Jones, Morgan H; Kaeding, Christopher C; Kamath, Ganesh V; Klootwyk, Thomas E; Levy, Bruce A; Ma, C Benjamin; Maiers, G Peter; Marx, Robert G; Matava, Matthew J; Mathien, Gregory M; McAllister, David R; McCarty, Eric C; McCormack, Robert G; Miller, Bruce S; Nissen, Carl W; O'Neill, Daniel F; Owens, Brett D; Parker, Richard D; Purnell, Mark L; Ramappa, Arun J; Rauh, Michael A; Rettig, Arthur C; Sekiya, Jon K; Shea, Kevin G; Sherman, Orrin H; Slauterbeck, James R; Smith, Matthew V; Spang, Jeffrey T; Svoboda, Steven J; Taft, Timothy N; Tenuta, Joachim J; Tingstad, Edwin M; Vidal, Armando F; Viskontas, Darius G; White, Richard A; Williams, James S; Wolcott, Michelle L; Wolf, Brian R; York, James J; Wright, Rick W

    2018-06-01

    The occurrence of physiologic knee hyperextension (HE) in the revision anterior cruciate ligament reconstruction (ACLR) population and its effect on outcomes have yet to be reported. Hypothesis/Purpose: The prevalence of knee HE in revision ACLR and its effect on 2-year outcome were studied with the hypothesis that preoperative physiologic knee HE ≥5° is a risk factor for anterior cruciate ligament (ACL) graft rupture. Cohort study; Level of evidence, 2. Patients undergoing revision ACLR were identified and prospectively enrolled between 2006 and 2011. Study inclusion criteria were patients undergoing single-bundle graft reconstructions. Patients were followed up at 2 years and asked to complete an identical set of outcome instruments (International Knee Documentation Committee, Knee injury and Osteoarthritis Outcome Score, WOMAC, and Marx Activity Rating Scale) as well as provide information regarding revision ACL graft failure. A regression model with graft failure as the dependent variable included age, sex, graft type at the time of the revision ACL surgery, and physiologic preoperative passive HE ≥5° (yes/no) to assess these as potential risk factors for clinical outcomes 2 years after revision ACLR. Analyses included 1145 patients, for whom 2-year follow-up was attained for 91%. The median age was 26 years, with age being a continuous variable. Those below the median were grouped as "younger" and those above as "older" (age: interquartile range = 20, 35 years), and 42% of patients were female. There were 50% autografts, 48% allografts, and 2% that had a combination of autograft plus allograft. Passive knee HE ≥5° was present in 374 (33%) patients in the revision cohort, with 52% being female. Graft rupture at 2-year follow-up occurred in 34 cases in the entire cohort, of which 12 were in the HE ≥5° group (3.2% failure rate) and 22 in the non-HE group (2.9% failure rate). The median age of patients who failed was 19 years, as opposed to 26 years

  8. Design of Polymer-Grafted Particles for Biocompatability

    NASA Astrophysics Data System (ADS)

    Trombly, David; Ganesan, Venkat

    2009-03-01

    Drug designers often coat drug particles with grafted polymers in order to introduce a net repulsion between the particles and blood proteins. This net repulsion results from the energy cost of compressing grafted chains on approach of proteins. It thus overcomes the Van Der Waals attraction between drug and protein which would otherwise cause particle-protein agglomeration and ultimately thrombosis. This study proposes to develop a fundamental understanding of the role of different features in controlling the efficacy of the grafted layers. We address this issue by developing a framework to predict the interactions between a polymer-coated spherical particle and a bare spherical particle. In order to fully capture the two-sphere system, a numerical solution of polymer mean field theory is used in a bispherical coordinate system. Results for protein-particle interaction energies for different design parameters will be presented. For biological applications, polyethylene glycol is often used as the grafted polymer. The unique properties of this molecule will be accounted for using the n-cluster model.

  9. Grafting in Arabidopsis.

    PubMed

    Bainbridge, Katherine; Bennett, Tom; Crisp, Peter; Leyser, Ottoline; Turnbull, Colin

    2014-01-01

    Grafting provides a simple way to generate chimeric plants with regions of different genotypes and thus to assess the cell autonomy of gene action. The technique of grafting has been widely used in other species, but in Arabidopsis, its small size makes the process rather more demanding. However, there are now several well-established grafting procedures available, which we described here, and their use has already contributed greatly to understanding of such processes as shoot branching control, flowering, disease resistance, and systemic silencing.

  10. Approaches to Peripheral Nerve Repair: Generations of Biomaterial Conduits Yielding to Replacing Autologous Nerve Grafts in Craniomaxillofacial Surgery

    PubMed Central

    Knipfer, Christian; Hadlock, Tessa

    2016-01-01

    Peripheral nerve injury is a common clinical entity, which may arise due to traumatic, tumorous, or even iatrogenic injury in craniomaxillofacial surgery. Despite advances in biomaterials and techniques over the past several decades, reconstruction of nerve gaps remains a challenge. Autografts are the gold standard for nerve reconstruction. Using autografts, there is donor site morbidity, subsequent sensory deficit, and potential for neuroma development and infection. Moreover, the need for a second surgical site and limited availability of donor nerves remain a challenge. Thus, increasing efforts have been directed to develop artificial nerve guidance conduits (ANCs) as new methods to replace autografts in the future. Various synthetic conduit materials have been tested in vitro and in vivo, and several first- and second-generation conduits are FDA approved and available for purchase, while third-generation conduits still remain in experimental stages. This paper reviews the current treatment options, summarizes the published literature, and assesses future prospects for the repair of peripheral nerve injury in craniomaxillofacial surgery with a particular focus on facial nerve regeneration. PMID:27556032

  11. Gum Graft Surgery

    MedlinePlus

    ... gum line and reduce sensitivity. What are the benefits of gum graft surgery? A gum graft can ... improve function or esthetics, patients often receive the benefits of both: a beautiful new smile and improved ...

  12. Protective constriction of coronary vein grafts with knitted nitinol

    PubMed Central

    Moodley, Loven; Franz, Thomas; Human, Paul; Wolf, Michael F.; Bezuidenhout, Deon; Scherman, Jacques; Zilla, Peter

    2013-01-01

    .00001) in CO + FS vs 82 ± 61% in ME + FS (P < 0.007). CONCLUSIONS In a senescent non-human primate model for coronary artery bypass grafts, constrictive, external mesh support of saphenous veins with knitted nitinol prevented focal, irregular graft narrowing and suppressed neointimal tissue proliferation by a factor of 2.5. The lower degree of suppression of IH compared with previous infrainguinal grafts coincided with a lesser reduction of calibre mismatch in the coronary grafts. PMID:23295444

  13. Skin grafts: a rural general surgical perspective.

    PubMed

    Henderson, Nigel J; Fancourt, Michael; Gilkison, William; Kyle, Stephen; Mosquera, Damien

    2009-05-01

    Skin grafts are a common method of closing skin defects. The literature comparing methods of graft application and subsequent outcomes is poor, but reports indicate a graft failure rate between 2 and 30%. The aim of this study was to audit our current skin graft practice. Data were collected prospectively on all skin grafts performed by the general surgical department between 1st December 2005 and 1st December 2006. A standardized proforma on each patient included data on age, gender, graft indication, application method, comorbidities, length of stay, and graft outcomes including graft take at 1, 2 and 6 weeks post-operatively. There were 85 grafts performed on 74 patients, median age 72 years (9-102 years), with 10 (12%) acute admissions. Prophylactic antibiotics were given to 50% (38 of 74) of patients. Successful grafts (>80% take) were performed in 68 (80%) patients. The overall graft complication rate was 24.7% (22 of 85 grafts). Infection occurred in 13 of 17 graft failures. No patients underwent re-operation for graft failure. Patients who received prophylactic antibiotics had a reduced risk of graft failure (Fisher's exact test, P = 0.016). Skin grafts were performed successfully in the majority of patients. Graft complication and failure rates compare well with the world literature. The use of prophylactic antibiotics was the only predictor of successful graft take.

  14. Effect of DEXTRAN-graft-POLYACRYLAMIDE Internal Structure on Flocculation Process Parameters

    NASA Astrophysics Data System (ADS)

    Bezugla, T.; Kutsevol, N.; Shyichuk, A.; Ziolkowska, D.

    2008-08-01

    Dextran-graft-Polyacrylamide copolymers (D-g-PAA) of brush-like architecture were tested as flocculation aids in the model kaolin suspensions. Due to expanded conformation the D-g-PAA copolymers are more effective flocculants than individual PAA with close molecular mass. The internal structure of D-g-PAA copolymers which is determined by number and length of grafted PAA chains, the distance between grafts, etc., has the significant influence on flocculation behavior of such polymers.

  15. Intercalary defects reconstruction of the femur and tibia after primary malignant bone tumour resection. A series of 13 cases.

    PubMed

    Brunet, O; Anract, P; Bouabid, S; Babinet, A; Dumaine, V; Toméno, B; Biau, D

    2011-09-01

    Performing intercalary segment reconstruction after malignant bone tumour resection results in both mechanical and biological challenges. Fixation must be solid enough to avoid short-term or mid-term mechanical failure. The use of an allograft or autograft must ensure long-term survival of the reconstruction. The goal of this study was to analyse the clinical and radiological outcomes of these reconstructions. Thirteen patients were operated on eight femurs and five tibias. The median age was 20 years old (range 14-50). The most common diagnosis was osteosarcoma. The median resection length was 15cm (Q1-Q3: 6-26). A plate was used for fixation in nine cases and an intramedullary locked nail in four cases. An isolated bone autograft was used in two cases, an isolated bone allograft in one case, a dual autograft-allograft composite in six cases, and vascularised fibula and allograft combination in four cases. The cumulative probability of union was 46% (95% CI: 0-99%) at 1 year; at the final follow-up, union was achieved in 12 patients (92%). Because of non-unions, 13 iterative procedures were needed to obtain these results. A non-displaced fracture of a cuboid-shaped tibial graft occurred in one patient, which was treated conservatively. Three infections occurred. The results of intercalary segmental defects reconstruction after bone tumour resection were good, both from an oncologic and radiological point-of-view. One or more iterative procedures are sometimes needed to finally obtain bone union. We prefer to use a free rectangular cuboidal tibial graft since reconstruction with a vascularised autograft is technically more difficult. The choice of fixation methods is still controversial and no approach was found to be superior. Level IV. Retrospective study. Copyright © 2011. Published by Elsevier Masson SAS.

  16. Robot-assisted antegrade in-situ fenestrated stent grafting.

    PubMed

    Riga, Celia V; Bicknell, Colin D; Wallace, Daniel; Hamady, Mohamad; Cheshire, Nicholas

    2009-05-01

    To determine the technical feasibility of a novel approach of in-situ fenestration of aortic stent grafts by using a remotely controlled robotic steerable catheter system in the porcine model. A 65-kg pig underwent robot-assisted bilateral antegrade in-situ renal fenestration of an abdominal aortic stent graft with subsequent successful deployment of a bare metal stent into the right renal artery. A 16-mm iliac extension covered stent served as the porcine aortic endograft. Under fluoroscopic guidance, the graft was punctured with a 20-G customized diathermy needle that was introduced and kept in place by the robotic arm. The needle was exchanged for a 4 x 20 mm cutting balloon before successful deployment of the renal stent. Robot-assisted antegrade in-situ fenestration is technically feasible in a large mammalian model. The robotic system enables precise manipulation, stable positioning, and minimum instrumentation of the aorta and its branches while minimizing radiation exposure.

  17. Robot-Assisted Antegrade In-Situ Fenestrated Stent Grafting

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Riga, Celia V., E-mail: c.riga@imperial.ac.uk; Bicknell, Colin D.; Wallace, Daniel

    2009-05-15

    To determine the technical feasibility of a novel approach of in-situ fenestration of aortic stent grafts by using a remotely controlled robotic steerable catheter system in the porcine model. A 65-kg pig underwent robot-assisted bilateral antegrade in-situ renal fenestration of an abdominal aortic stent graft with subsequent successful deployment of a bare metal stent into the right renal artery. A 16-mm iliac extension covered stent served as the porcine aortic endograft. Under fluoroscopic guidance, the graft was punctured with a 20-G customized diathermy needle that was introduced and kept in place by the robotic arm. The needle was exchanged formore » a 4 x 20 mm cutting balloon before successful deployment of the renal stent. Robot-assisted antegrade in-situ fenestration is technically feasible in a large mammalian model. The robotic system enables precise manipulation, stable positioning, and minimum instrumentation of the aorta and its branches while minimizing radiation exposure.« less

  18. Inducement of semitendinosus tendon regeneration to the pes anserinus after its harvest for anterior cruciate ligament reconstruction-A new inducer grafting technique

    PubMed Central

    2012-01-01

    Purpose To investigate the usefulness of the “inducer grafting” technique for regeneration of the semitendinosus (ST) tendon after its harvest for anterior cruciate ligament (ACL) reconstruction. Methods Twenty knees of 20 patients (mean age at the time of surgery, 23.1 years) underwent ACL reconstruction with a double bundle autograft using the ST tendon (7 patients) and the ST + the gracilis (G) tendons (13 patients). “Inducer grafting” technique After harvesting the ST tendon, a passing pin with a loop thread is inserted along with the tendon stripper. The passing pin is pulled out from the medial thigh and the loop thread retained. As an inducer graft, the ST tendon branch is used. After the ACL graft has been secured, the inducer graft is sutured to the pes anserinus and the proximal end passed through by pulling the thread out. Then the inducer graft is placed within the tendon canal. The mean follow-up period was 15 months. The presence and morphology of the regenerated ST tendon were examined by MRI. And the isometric hamstring strength was examined at 45°, 90° and 120° of knee flexion. Results One month after the operation in all the patients, MRI demonstrated a low-intensity structure at the anatomical location of the ST, at the level of the superior pole of the patella and the joint line, apparently representing the regenerated ST tendon. Four months after the operation, the distal portion of the regenerated ST tendon had reached the pes anserinus in all patients. Twelve months after the operation, the regenerated ST tendon was hypertrophic in 19 of the 20 patients (95%). The isometric knee flexion torque of the ACL-reconstructed limb was significantly lower at 90° and 120° compared with the contralateral limb. Conclusion These results suggest that the “inducer grafting” technique is able to improve the regeneration rate of the harvested ST tendon and promote hypertrophy of the regenerated ST tendon, extending all the way to the pes

  19. The effect of platelet-derived growth factors on knee stability after anterior cruciate ligament reconstruction: a prospective randomized clinical study.

    PubMed

    Vogrin, Matjaz; Rupreht, Mitja; Crnjac, Anton; Dinevski, Dejan; Krajnc, Zmago; Recnik, Gregor

    2010-05-01

    Arthroscopic reconstruction is a standard surgical procedure in cases of symptomatic knee instability due to rupture of the anterior cruciate ligament. Bone-tendon-bone and hamstring tendon grafts are both in use for anterior cruciate ligament reconstruction. There are no significant differences between the two types of graft in relation to function scores, but there is a difference in anteroposterior stability when measured on the KT-2000 arthrometer: knee joints after reconstruction with bone-tendon-bone autografts are more stable than those reconstructed with hamstring tendon autografts. To improve knee stability after anterior cruciate ligament reconstruction with a hamstring graft and use of platelet-derived growth factors. Platelet-leukocyte gel was produced from platelet-leukocyte-rich plasma prepared from a unit of whole blood in an autologous platelet separator. The gel was applied locally, after hamstring graft placement. Fifty patients were included in the study: 25 in the platelet gel group, 25 in a control group. We evaluated anteroposterior knee stability with the KT-2000 arthrometer before surgery and at 3 and 6 months after surgery. Patients treated with the gel demonstrated significantly better anteroposterior knee stability than patients in the control group. The calculated improvements in knee stability at 6 months were 1.3 +/- 1.8 mm in the control group and 3.1 +/- 2.5 mm in the platelet gel group (P = 0.011). Platelet-leukocyte gel, applied locally, can improve knee stability in surgery for reconstruction of the anterior cruciate ligament.

  20. Skin graft - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100100.htm Skin graft - series—Normal anatomy To use the sharing features ... entire body, and acts as a protective barrier. Skin grafts may be recommended for: Extensive wounds Burns Specific ...

  1. Graft survival after cardiac transplantation for alcohol cardiomyopathy.

    PubMed

    Brinkley, D Marshall; Novak, Eric; Topkara, Veli K; Geltman, Edward M

    2014-08-27

    Alcohol cardiomyopathy (ACM) constitutes up to 40% of patients with non-ischemic dilated cardiomyopathy. Transplant-free survival is worse for patients with ACM versus idiopathic dilated cardiomyopathy (IDCM) with continued exposure. The prognosis for patients with ACM after cardiac transplantation is unknown. We evaluated adults who underwent single-organ, cardiac transplantation from 1994 to 2009 with a diagnosis of ACM (n=134) or IDCM (n=10,243) in the Organ Procurement Transplantation Network registry. Kaplan-Meier curves were generated by cohort for time until graft failure, cardiac allograft vasculopathy, and hospitalization for rejection. A Cox proportional hazards model was created to determine factors associated with each outcome. Patients with ACM were more likely to be males (P<0.0001), minorities (P<0.0001), and smokers (P=0.0310) compared with IDCM. Overall graft survival was lower for the ACM cohort (P=0.0001). After multivariate analysis, ACM was not independently associated with graft survival (HR 1.341, 95% CI 0.944-1.906, P=0.1017). Creatinine, total bilirubin, minority ethnicity, graft under-sizing, life support, diabetes, and donor age were independent predictors of graft failure. There were no significant differences between primary cause of death, vasculopathy, or rejection. There was no association between ACM and graft survival in this large registry study, but poorer overall survival in the ACM cohort was associated with other recipient characteristics.

  2. Upper limb grafts for hemodialysis access.

    PubMed

    Shemesh, David; Goldin, Ilya; Verstandig, Anthony; Berelowitz, Daniel; Zaghal, Ibrahim; Olsha, Oded

    2015-01-01

    Arteriovenous (AV) grafts are required for hemodialysis access when options for native fistulas have been fully exhausted, where they continue to play an important role in hemodialysis patients, offering a better alternative to central vein catheters. When planning autogenous accesses using Doppler ultrasound, adequate arterial inflow and venous outflow must be consciously preserved for future access creation with grafts. Efforts to improve graft patency include changing graft configuration, graft biology and hemodynamics. Industry offers early cannulation grafts to reduce central catheter use and a bioengineered graft is undergoing clinical studies. Although the outcome of AV grafts is inferior to fistulas, grafts can provide long-term hemodialysis access that is a better alternative to central venous catheters. AV grafts have significant drawbacks, mainly poor patency, infection and cost but also have some advantages: early maturation, ease of creation and needling and widespread availability. The outcome of AV graft surgery is variable from center to center. The primary patency rate for AV grafts is 58% at 6 months and the secondary patency rate is 76% at 6 months and 55% at 18 months. There are centers of excellence that report a 1 year secondary patency rate of up to 91%. In this review of the use of AV grafts for hemodialysis access in the upper extremities, technical issues involved in planning the access and performing the surgery in its different configurations are discussed and the role of surveillance and maintenance with their attendant surgical and radiological interventions is described.

  3. A new grafting technique for tympanoplasty: tympanoplasty with a boomerang-shaped chondroperichondrial graft (TwBSCPG).

    PubMed

    Dündar, Rıza; Soy, Fatih Kemal; Kulduk, Erkan; Muluk, Nuray Bayar; Cingi, Cemal

    2014-10-01

    The aim of this study was to introduce a new grafting technique in tympanoplasty that involves use of a boomerang-shaped chondroperichondrial graft (BSCPG). The anatomical and functional results were evaluated. A new tympanoplasty with boomerang-shaped chondroperichondrial graft (TwBSCPG) technique was used in 99 chronic otitis media patients with central or marginal perforation of the tympanic membrane and a normal middle ear mucosa. All 99 patients received chondroperichondrial cartilage grafts with a boomerang-shaped cartilage island left at the anterior and inferior parts. Postoperative follow-ups were conducted at months 1, 6, and 12. Preoperative and postoperative audiological examinations were performed and air-bone gaps were calculated according to the pure-tone averages (PTAs) of the patients. In the preoperative period, most (83.8%) air-bone gaps were ≥ 16 dB; after operating using the TwBSCPG technique, the air-bone gaps decreased to 0-10 dB in most patients (77.8%). In the TwBSCPG patients, the mean preoperative air-bone gap was 22.02 ± 6.74 dB SPL. Postoperatively, the mean postoperative air-bone gap was 8.70 ± 5.74 dB SPL. The TwBSCPG technique therefore decreased the postoperative air-bone gap compared to that preoperatively (p = 0.000, z = -8.645). At the 1-month follow-up, there were six graft perforations and one graft retraction. At the 6-month follow-up, there were nine graft perforations and three graft retractions. At 12 months, there were seven graft perforations and four graft retractions. During the first year after the boomerang tympanoplasty surgery, graft lateralization was not detected in any patient. Retractions were grade 1 according to the Sade classification and were localized to the postero-superior quadrant of the tympanic membrane. The TwBSCPG technique has benefits with respect to postoperative anatomical and audiological results. It prevents perforation of the tympanic membrane at the anterior quadrant and avoids graft

  4. Micro-Computed Tomography Evaluation of Human Fat Grafts in Nude Mice

    PubMed Central

    Chung, Michael T.; Hyun, Jeong S.; Lo, David D.; Montoro, Daniel T.; Hasegawa, Masakazu; Levi, Benjamin; Januszyk, Michael; Longaker, Michael T.

    2013-01-01

    Background Although autologous fat grafting has revolutionized the field of soft tissue reconstruction and augmentation, long-term maintenance of fat grafts is unpredictable. Recent studies have reported survival rates of fat grafts to vary anywhere between 10% and 80% over time. The present study evaluated the long-term viability of human fat grafts in a murine model using a novel imaging technique allowing for in vivo volumetric analysis. Methods Human fat grafts were prepared from lipoaspirate samples using the Coleman technique. Fat was injected subcutaneously into the scalp of 10 adult Crl:NU-Foxn1nu CD-1 male mice. Micro-computed tomography (CT) was performed immediately following injection and then weekly thereafter. Fat volume was rendered by reconstructing a three-dimensional (3D) surface through cubic-spline interpolation. Specimens were also harvested at various time points and sections were prepared and stained with hematoxylin and eosin (H&E), for macrophages using CD68 and for the cannabinoid receptor 1 (CB1). Finally, samples were explanted at 8- and 12-week time points to validate calculated micro-CT volumes. Results Weekly CT scanning demonstrated progressive volume loss over the time course. However, volumetric analysis at the 8- and 12-week time points stabilized, showing an average of 62.2% and 60.9% survival, respectively. Gross analysis showed the fat graft to be healthy and vascularized. H&E analysis and staining for CD68 showed minimal inflammatory reaction with viable adipocytes. Immunohistochemical staining with anti-human CB1 antibodies confirmed human origin of the adipocytes. Conclusions Studies assessing the fate of autologous fat grafts in animals have focused on nonimaging modalities, including histological and biochemical analyses, which require euthanasia of the animals. In this study, we have demonstrated the ability to employ micro-CT for 3D reconstruction and volumetric analysis of human fat grafts in a mouse model. Importantly

  5. Numerical Assessment of Novel Helical/Spiral Grafts with Improved Hemodynamics for Distal Graft Anastomoses

    PubMed Central

    Kabinejadian, Foad; McElroy, Michael; Ruiz-Soler, Andres; Leo, Hwa Liang; Slevin, Mark A.; Badimon, Lina

    2016-01-01

    In the present work, numerical simulations were conducted for a typical end-to-side distal graft anastomosis to assess the effects of inducing secondary flow, which is believed to remove unfavourable flow environment. Simulations were carried out for four models, generated based on two main features of 'out-of-plane helicity' and 'spiral ridge' in the grafts as well as their combination. Following a qualitative comparison against in vitro data, various mean flow and hemodynamic parameters were compared and the results showed that helicity is significantly more effective in inducing swirling flow in comparison to a spiral ridge, while their combination could be even more effective. In addition, the induced swirling flow was generally found to be increasing the wall shear stress and reducing the flow stagnation and particle residence time within the anastomotic region and the host artery, which may be beneficial to the graft longevity and patency rates. Finally, a parametric study on the spiral ridge geometrical features was conducted, which showed that the ridge height and the number of spiral ridges have significant effects on inducing swirling flow, and revealed the potential of improving the efficiency of such designs. PMID:27861485

  6. Adolescent External Iliac Artery Trauma: Recurrent Aneurysmal Dilatation of an Iliofemoral Saphenous Vein Graft Treated by Stent-Grafting

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lenton, James, E-mail: jlenton@doctors.org.u; Davies, John; Homer-Vanniasinkam, S.

    An adolescent male sustained a severe penetrating injury to the external iliac artery. Emergency surgical revascularization was with a reversed long saphenous vein interposition graft. The primary graft and the subsequent revision graft both became aneurysmal. The second graft aneurysm was successfully excluded by endovascular stent-grafts with medium-term primary patency. A venous graft was used initially rather than a synthetic graft to reduce the risk of infection and the potential problems from future growth. Aneurysmal dilatation of venous grafts in children and adolescents is a rare but recognized complication. To the best of our knowledge, exclusion of these aneurysms withmore » stent-grafts has not been previously reported in the adolescent population.« less

  7. Compliance Study of Endovascular Stent Grafts Incorporated with Polyester and Polyurethane Graft Materials in both Stented and Unstented Zones

    PubMed Central

    Guan, Ying; Wang, Lu; Lin, Jing; King, Martin W.

    2016-01-01

    Compliance mismatch between stent graft and host artery may induce complications and blood flow disorders. However, few studies have been reported on stent graft compliance. This study aims to explore the deformation and compliance of stent graft in stented and unstented zones under three pressure ranges. Compliance of two stent grafts incorporated with polyurethane graft (nitinol-PU) and polyester graft (nitinol-PET) materials respectively were tested; the stents used in the two stent grafts were identical. For the circumferential deformation of the stent grafts under each pressure range, the nitinol-PET stent graft was uniform in both zones. The nitinol-PU stent graft was circumferentially uniform in the stented zone, however, it was nonuniform in the unstented zone. The compliance of the PU graft material was 15 times higher than that of the PET graft. No significant difference in compliance was observed between stented and unstented zones of the nitinol-PET stent graft regardless of the applied pressure range. However, for the nitinol-PU stent graft, compliance of the unstented PU region was approximately twice that of the stented region; thus, compliance along the length of the nitinol-PU stent graft was not constant and different from that of the nitinol-PET stent graft. PMID:28773781

  8. Surgical management of cosmetic mucogingival defects.

    PubMed

    Dym, Harry; Tagliareni, Jonathan M

    2012-01-01

    Mucogingival conditions are deviations from the normal anatomic relationship between the gingival margin and the mucogingival junction. Mucogingival surgery is plastic surgery designed to correct defects in the gingiva surrounding the teeth. Common mucogingival conditions are recession, absence, or reduction of keratinized tissue, and probing depths extending beyond the mucogingival junction. Surgical techniques used to augment cosmetic mucogingival defects include the free gingival autograft, the subepithelial connective tissue graft, rotational flaps, lateral sliding flaps, coronally repositioned flaps, and the use of acellular dermal matrix grafts. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. pHEMA-nHA encapsulation and delivery of vancomycin and rhBMP-2 enhances its role as a bone graft substitute.

    PubMed

    Li, Xinning; Xu, Jianwen; Filion, Tera M; Ayers, David C; Song, Jie

    2013-08-01

    Bone grafts are widely used in orthopaedic procedures. Autografts are limited by donor site morbidity while allografts are known for considerable infection and failure rates. A synthetic composite bone graft substitute poly(2-hydroxyethyl methacrylate)-nanocrystalline hydroxyapatite (pHEMA-nHA) was previously developed to stably press-fit in and functionally repair critical-sized rat femoral segmental defects when it was preabsorbed with a single low dose of 300 ng recombinant human bone morphogenetic protein-2/7 (rhBMP-2/7). To facilitate clinical translation of pHEMA-nHA as a synthetic structural bone graft substitute, we examined its ability to encapsulate and release rhBMP-2 and the antibiotic vancomycin. We analyzed the compressive behavior and microstructure of pHEMA-nHA as a function of vancomycin incorporation doses using a dynamic mechanical analyzer and a scanning electron microscope. In vitro release of vancomycin was monitored by ultraviolet-visible spectroscopy. Release of rhBMP-2 from pHEMA-nHA-vancomycin was determined by ELISA. Bioactivity of the released vancomycin and rhBMP-2 was examined by bacterial inhibition and osteogenic transdifferentiation capabilities in cell culture, respectively. Up to 4.8 wt% of vancomycin was incorporated into pHEMA-nHA without compromising its structural integrity and compressive modulus. Encapsulated vancomycin was released in a dose-dependent and sustained manner in phosphate-buffered saline over 2 weeks, and the released vancomycin inhibited Escherichia coli culture. The pHEMA-nHA-vancomycin composite released preabsorbed rhBMP-2 in a sustained manner over 8 days and locally induced osteogenic transdifferentiation of C2C12 cells in culture. pHEMA-nHA can encapsulate and deliver vancomycin and rhBMP-2 in a sustained and localized manner with reduced loading doses. The elasticity, osteoconductivity, and rhBMP-2/vancomycin delivery characteristics of pHEMA-nHA may benefit orthopaedic reconstructions or fusions with

  10. Similar Outcomes in Diabetes Patients After Coronary Artery Bypass Grafting With Single Internal Thoracic Artery Plus Radial Artery Grafting and Bilateral Internal Thoracic Artery Grafting.

    PubMed

    Raza, Sajjad; Blackstone, Eugene H; Houghtaling, Penny L; Koprivanac, Marijan; Ravichandren, Kirthi; Javadikasgari, Hoda; Bakaeen, Faisal G; Svensson, Lars G; Sabik, Joseph F

    2017-12-01

    The purpose of this study was to determine in patients with diabetes mellitus whether single internal thoracic artery (SITA) plus radial artery (RA) grafting yields outcomes similar to those of bilateral internal thoracic artery (BITA) grafting. From January 1994 to January 2011, 1,325 diabetic patients underwent primary isolated coronary artery bypass graft surgery with either (1) SITA plus RA with or without saphenous vein (SV) grafts (n = 965) or (2) BITA with or without SV grafts (n = 360); an internal thoracic artery was used in all patients to graft the left anterior descending coronary artery. Endpoints were in-hospital outcomes and time-related mortality. Median follow-up was 7.4 years, with a total follow-up of 9,162 patient-years. Propensity score matching was performed to identify 282 well-matched pairs for adjusted comparisons. Unadjusted in-hospital mortality was 0.52% for SITA plus RA with or without SV grafts and 0.28% for BITA with or without SV grafts, and prevalence of deep sternal wound infection was 3.2% and 1.7%, respectively. Unadjusted survival at 1, 5, 10, and 14 years was 97%, 88%, 68%, and 51% for SITA plus RA with or without SV grafts, and 97%, 95%, 80%, and 66% for BITA with or without SV grafts, respectively. Among propensity-matched patients, in-hospital mortality (0.35% versus 0.35%) and prevalence of deep sternal wound infection (1.4% versus 1.4%) were similar (p > 0.9) in the two groups, as was 1-, 5-, 10-, and 14-year survival: 97%, 90%, 70%, and 58% for SITA plus RA with or without SV grafting versus 97%, 93%, 79%, and 64% for BITA with or without SV grafting, respectively (early p = 0.8, late p = 0.2). For diabetic patients, SITA plus RA with or without SV grafting and BITA with or without SV grafting yield similar in-hospital outcomes and long-term survival after coronary artery bypass graft surgery. Therefore, both SITA plus RA and BITA plus SV grafting should be considered for these patients. Copyright © 2017 The Society

  11. Donor Indocyanine Green Clearance Test Predicts Graft Quality and Early Graft Prognosis After Liver Transplantation.

    PubMed

    Tang, Yunhua; Han, Ming; Chen, Maogen; Wang, Xiaoping; Ji, Fei; Zhao, Qiang; Zhang, Zhiheng; Ju, Weiqiang; Wang, Dongping; Guo, Zhiyong; He, Xiaoshun

    2017-11-01

    Transplantation centers have given much attention to donor availability. However, no reliable quantitative methods have been employed to accurately assess graft quality before transplantation. Here, we report that the indocyanine green (ICG) clearance test is a valuable index for liver grafts. We performed the ICG clearance test on 90 brain-dead donors within 6 h before organ procurement between March 2015 and November 2016. We also analyzed the relationship between graft liver function and early graft survival after liver transplantation (LT). Our results suggest that the ICG retention rate at 15 min (ICGR15) of donors before procurement was independently associated with 3-month graft survival after LT. The best donor ICGR15 cutoff value was 11.0%/min, and we observed a significant increase in 3-month graft failure among patients with a donor ICGR15 above this value. On the other hand, a donor ICGR15 value of ≤ 11.0%/min could be used as an early assessment index of graft quality because it provides additional information to the transplant surgeon or organ procurement organization members who must maintain or improve organ function to adapt the LT. An ICG clearance test before liver procurement might be an effective quantitative method to predict graft availability and improve early graft prognosis after LT.

  12. Surgical option for the correction of Peyronie's disease: an autologous tissue-engineered endothelialized graft.

    PubMed

    Imbeault, Annie; Bernard, Geneviève; Ouellet, Gabrielle; Bouhout, Sara; Carrier, Serge; Bolduc, Stéphane

    2011-11-01

    Surgical treatment is indicated in severe cases of Peyronie's disease. Incision of the plaque with subsequent graft material implantation is the option of choice. Ideal graft tissue is not yet available. To evaluate the use of an autologous tissue-engineered endothelialized graft by the self-assembly method, for tunica albuginea (TA) reconstruction in Peyronie's disease. Two TA models were created. Human fibroblasts were isolated from a skin biopsy and cultured in vitro until formation of fibroblast sheets. After 4 weeks of maturation, human umbilical vein endothelial cells (HUVEC) were seeded on fibroblasts sheets and wrapped around a tubular support to form a cylinder of about 10 layers. After 21 days of tube maturation, HUVEC were seeded into the lumen of the fibroblast tubes for the endothelialized tunica albuginea (ETA). No HUVEC were seeded into the lumen for the TA model. Both constructs were placed under perfusion in a bioreactor for 1 week. Histology, immunohistochemistry, and burst pressure were performed to characterize mature tubular graft. Animal manipulations were also performed to demonstrate the impact of endothelial cells in vivo. Histology showed uniform multilayered fibroblasts. Extracellular matrix, produced entirely by fibroblasts, presented a good staining for collagen 1. Some elastin fibers were also present. For the TA model, anti-human von Willebrand antibody revealed the endothelial cells forming capillary-like structures. TA model reached a burst pressure of 584 mm Hg and ETA model obtained a burst pressure of 719 mm Hg. This tissue-engineered endothelialized tubular graft is structurally similar to normal TA and presents an adequate mechanical resistance. The self-assembly method used and the autologous property of this model could represent an advantage comparatively to other available grafts. Further evaluation including functional testing will be necessary to characterize in vivo implantation and behavior of the graft. © 2011

  13. Comparison of mitomycin C and limbal-conjunctival autograft in the prevention of pterygial recurrence in Turkish patients: A one-year, randomized, assessor-masked, controlled trial

    PubMed Central

    Ari, Şeyhmus; Çaca, Îhsan; Yildiz, Zennure Özdemir; Şakalar, Yildirim Bayezit; Dogan, Eyüp

    2009-01-01

    Background: A pterygium is a fibrovascular overgrowth of degenerative bulbar conjunctival tissue that grows over the limbus onto the cornea. Although various approaches have been proposed for the treatment of pterygium, the common problem after these treatments is recurrence. Objectives: The goals of this study were to compare the efficacy of mitomycin C (MMC) and limbal-conjunctival autograft (LCAU) in preventing recurrence of primary pterygia and to monitor long-term adverse effects (AEs). Methods: Patients undergoing pterygium surgery between February 2006 and May 2007 were assessed prospectively and randomly divided into 2 groups using a random number table. The MMC group underwent pterygium excision and received 0.02% MMC intraoperatively for 2 minutes. The LCAU group underwent pterygium excision and LCAU. Recurrence and AE rates of the 2 treatments were compared during the 1-year follow-up period. Assessors for pterygial recurrence were masked to treatment group. Results: One hundred thirteen eyes (57 patients in the MMC group and 56 patients in the LCAU group) were included in the study. Thirteen of the patients (7 in the MMC group and 6 in the LCAU group) were withdrawn due to irregular attendance at follow-up visits or lack of sufficient dose and duration for postoperative topical antibiotic and steroid administration; their data were excluded from analysis. Fifty patients (MMC group: 26 men, 24 women; mean [SD] age, 48.0 [12.3] years; age range, 30–73 years; LCAU group: 27 men, 23 women; mean age, 49.0 [12.6] years; age range, 28–71 years) in each group completed the study. The mean (SD) length of the pterygium across the limbus was similar in the MMC group and the LCAU group (4.18 [1.27] vs 4.07 [1.24] mm). The mean follow-up period was also similar in the 2 groups (16.0 [1.9] vs 15.0 [1.7] months). The rate of recurrence was significantly greater in the MMC group than in the LCAU group (10 [20.0%] vs 2 [4.0%] patients; P=0.035). Seven patients (14

  14. Leoligin, the major lignan from Edelweiss, inhibits intimal hyperplasia of venous bypass grafts

    PubMed Central

    Reisinger, Ute; Schwaiger, Stefan; Zeller, Iris; Messner, Barbara; Stigler, Robert; Wiedemann, Dominik; Mayr, Tobias; Seger, Christoph; Schachner, Thomas; Dirsch, Verena M.; Vollmar, Angelika M.; Bonatti, Johannes O.; Stuppner, Hermann; Laufer, Günther; Bernhard, David

    2009-01-01

    Aims Despite the lower patency of venous compared with arterial coronary artery bypass grafts, ∼50% of grafts used are saphenous vein conduits because of their easier accessibility. In a search for ways to increase venous graft patency, we applied the results of a previous pharmacological study screening for non-toxic compounds that inhibit intimal hyperplasia of saphenous vein conduits in organ cultures. Here we analyse the effects and mechanism of action of leoligin [(2S,3R,4R)-4-(3,4-dimethoxybenzyl)-2-(3,4-dimethoxyphenyl)tetrahydrofuran-3-yl]methyl (2Z)-2-methylbut-2-enoat, the major lignan from Edelweiss (Leontopodium alpinum Cass.). Methods and results We found that leoligin potently inhibits vascular smooth muscle cell (SMC) proliferation by inducing cell cycle arrest in the G1-phase. Leoligin induced cell death neither in SMCs nor, more importantly, in endothelial cells. In a human saphenous vein organ culture model for graft disease, leoligin potently inhibited intimal hyperplasia, and even reversed graft disease in pre-damaged vessels. Furthermore, in an in vivo mouse model for venous bypass graft disease, leoligin potently inhibited intimal hyperplasia. Conclusion Our data suggest that leoligin might represent a novel non-toxic, non-thrombogenic, endothelial integrity preserving candidate drug for the treatment of vein graft disease. PMID:19228707

  15. Endothelial chimerism and vascular sequestration protect pancreatic islet grafts from antibody-mediated rejection

    PubMed Central

    Chen, Chien-Chia; Pouliquen, Eric; Broisat, Alexis; Andreata, Francesco; Racapé, Maud; Bruneval, Patrick; Kessler, Laurence; Ahmadi, Mitra; Bacot, Sandrine; Saison-Delaplace, Carole; Marcaud, Marina; Van Huyen, Jean-Paul Duong; Loupy, Alexandre; Villard, Jean; Demuylder-Mischler, Sandrine; Morelon, Emmanuel; Tsai, Meng-Kun; Kolopp-Sarda, Marie-Nathalie; Koenig, Alice; Mathias, Virginie; Ghezzi, Catherine; Dubois, Valerie; Defrance, Thierry

    2017-01-01

    Humoral rejection is the most common cause of solid organ transplant failure. Here, we evaluated a cohort of 49 patients who were successfully grafted with allogenic islets and determined that the appearance of donor-specific anti-HLA antibodies (DSAs) did not accelerate the rate of islet graft attrition, suggesting resistance to humoral rejection. Murine DSAs bound to allogeneic targets expressed by islet cells and induced their destruction in vitro; however, passive transfer of the same DSAs did not affect islet graft survival in murine models. Live imaging revealed that DSAs were sequestrated in the circulation of the recipients and failed to reach the endocrine cells of grafted islets. We used murine heart transplantation models to confirm that endothelial cells were the only accessible targets for DSAs, which induced the development of typical microvascular lesions in allogeneic transplants. In contrast, the vasculature of DSA-exposed allogeneic islet grafts was devoid of lesions because sprouting of recipient capillaries reestablished blood flow in grafted islets. Thus, we conclude that endothelial chimerism combined with vascular sequestration of DSAs protects islet grafts from humoral rejection. The reduced immunoglobulin concentrations in the interstitial tissue, confirmed in patients, may have important implications for biotherapies such as vaccines and monoclonal antibodies. PMID:29202467

  16. Small interfering RNA targeting nuclear factor kappa B to prevent vein graft stenosis in rat models.

    PubMed

    Meng, X B; Bi, X L; Zhao, H L; Feng, J B; Zhang, J P; Song, G M; Sun, W Y; Bi, Y W

    2013-01-01

    Intimal hyperplasia plays an important role in vein graft stenosis. Inflammatory injury, especially nuclear factor kappaB (NF-κB) gene activation, is highly involved in stenosis progression. We examined whether neointimal hyperplasia and vein graft stenosis could be inhibited by silencing the NF-κB gene with small interference RNA (siRNA). Sixty adult male Sprague-Dawley rats were randomly divided into a normal vein group, a vein graft group, a scrambled siRNA group, and an NF-κB siRNA group. We performed reverse interpositional grafting of the autologous external jugular vein to the abdominal aorta. Vein grafts were treated with liposome and gel complexes containing NF-κB siRNA or scrambled siRNA. The levels of monocyte chemoattractant protein -1, tumor necrosis factor-α, and NF-κB p65 in vessel tissues were evaluated after surgery for content of proliferating cell nuclear antigen (PCNA) and vascular wall thickness. NF-κB siRNA treated vein graft showed less neointimal formation and fewer positive PCNA cells (P < .05). In addition there were lower levels of, NF-κB p65 protein and of inflammatory mediators (P < .05) compared with the vein graft group. Our study suggested that siRNA transfection suppressed NF-κB expression, reduced inflammatory factors, lessened neointimal proliferation, and suppressed PCNA. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Steroid-induced femoral head osteonecrosis in immune thrombocytopenia treatment with osteochondral autograft transplantation.

    PubMed

    Fotopoulos, Vasileios Ch; Mouzopoulos, George; Floros, Themistoklis; Tzurbakis, Matthaios

    2015-09-01

    Osteonecrosis of the femoral head is a devastating complication of steroid administration and has rarely been observed in the treatment of immune thrombocytopenia. The treatment of osteochondral defects in advanced stages of avascular necrosis (AVN), characterized by collapse of the subchondral bone, remains an unsolved burden in orthopedic surgery. In this report, we present a case of a 19-year-old female that was admitted in the Emergency Department with walking disability and painful hip joint movement due to steroid-induced femoral head osteonecrosis. Two years before she was diagnosed with immune thrombocytopenia, for which she received pulse steroid therapy with high dose of dexamethasone and underwent a splenectomy. This case report is the first to describe the use of osteochondral autograft transplantation as a treatment of steroid-induced AVN of the femoral head due to immune thrombocytopenia at the age of 19 years with very good clinical and radiological results 3 years postoperatively.

  18. Organization model for allotransplantations of cryopreserved vascular grafts in Czech Republic.

    PubMed

    Špaček, Miroslav; Měřička, Pavel; Janoušek, Libor; Štádler, Petr; Adamec, Miloš; Vlachovský, Robert; Guňka, Igor; Navrátil, Pavel; Thieme, Filip; Mitáš, Petr; Špunda, Rudolf; Špatenka, Jaroslav; Staffa, Robert; Němec, Petr; Lindner, Jaroslav

    2018-03-03

    The transplantation of fresh or cryopreserved vascular allografts in patients with a prosthetic graft infection or critical limb ischemia is necessary for their limb salvage and, in many cases, represents a lifesaving procedure. While transplantation of fresh allografts has a long history in the Czech Republic, the standard use of cryopreserved vascular allografts was introduced into the clinical practice in 2011 as a result of the implementation of EU Directive 2004/23/EC into national legislation (Human Cell and Tissue Act No. 296/2008 Coll.). The authors present an organizational model based on cooperation between the majority of Czech Transplant Centers with a tissue establishment licensed by the national competent authority. In various points, we are addressing individual aspects of experimental and clinical studies which affect clinical practice. Based on experimental and clinical work, the first validation of cryopreserved arterial and venous grafts for clinical use was performed between 2011 and 2013. The growing number of centers participating in this programme led to a growing number of patients who underwent transplantation of vascular allografts. In 2015 the numbers of transplanted fresh versus cryopreserved allografts in the Czech Republic were almost equal. Cooperation of the participating centers in the Czech Republic with the licensed Tissue Establishment made it possible to achieve a full compliance with the European Union Directives, and harmonized national legal norms and assured a high quality of cryopreserved vascular allografts.

  19. Skin graft take and healing following 193-nm excimer, continuous-wave carbon dioxide (CO2), pulsed CO2, or pulsed holmium: YAG laser ablation of the graft bed.

    PubMed

    Green, H A; Burd, E E; Nishioka, N S; Compton, C C

    1993-08-01

    Ablative lasers have been used for cutaneous surgery for greater than two decades since they can remove skin and skin lesions bloodlessly and efficiently. Because full-thickness skin wounds created after thermal laser ablation may require skin grafting in order to heal, we have examined the effect of the residual laser-induced thermal damage in the wound bed on subsequent skin graft take and healing. In a pig model, four different pulsed and continuous-wave lasers with varying wavelengths and radiant energy exposures were used to create uniform fascial graft bed thermal damage of approximately 25, 160, 470, and 1100 microns. Meshed split-thickness skin graft take and healing on the thermally damaged fascial graft beds were examined on a gross and microscopic level on days 3 and 7, and then weekly up to 42 days. Laser-induced thermal damage on the graft bed measuring greater than 160 +/- 60 microns in depth significantly decreased skin graft take. Other deleterious effects included delayed graft revascularization, increased inflammatory cell infiltrate at the graft-wound bed interface, and accelerated formation of hypertrophied fibrous tissue within the graft bed and underlying muscle. Ablative lasers developed for cutaneous surgery should create less than 160 +/- 60 microns of residual thermal damage to permit optimal skin graft take and healing. Pulsed carbon dioxide and 193-nm excimer lasers may be valuable instruments for the removal of full-thickness skin, skin lesions, and necrotic tissue, since they create wound beds with minimal thermal damage permitting graft take comparable to that achieved with standard surgical techniques.

  20. Metabolic Profiles Predict Adverse Events Following Coronary Artery Bypass Grafting

    PubMed Central

    Shah, Asad A.; Craig, Damian M.; Sebek, Jacqueline K.; Haynes, Carol; Stevens, Robert C.; Muehlbauer, Michael J.; Granger, Christopher B.; Hauser, Elizabeth R.; Newby, L. Kristin; Newgard, Christopher B.; Kraus, William E.; Hughes, G. Chad; Shah, Svati H.

    2012-01-01

    Objectives Clinical models incompletely predict outcomes following coronary artery bypass grafting. Novel molecular technologies may identify biomarkers to improve risk stratification. We examined whether metabolic profiles can predict adverse events in patients undergoing coronary artery bypass grafting. Methods The study population comprised 478 subjects from the CATHGEN biorepository of patients referred for cardiac catheterization who underwent coronary artery bypass grafting after enrollment. Targeted mass spectrometry-based profiling of 69 metabolites was performed in frozen, fasting plasma samples collected prior to surgery. Principal-components analysis and Cox proportional hazards regression modeling were used to assess the relation between metabolite factor levels and a composite outcome of post-coronary artery bypass grafting myocardial infarction, need for percutaneous coronary intervention, repeat coronary artery bypass grafting, or death. Results Over a mean follow-up of 4.3 ± 2.4 years, 126 subjects (26.4%) suffered an adverse event. Three principal-components analysis-derived factors were significantly associated with adverse outcome in univariable analysis: short-chain dicarboxylacylcarnitines (factor 2, P=0.001); ketone-related metabolites (factor 5, P=0.02); and short-chain acylcarnitines (factor 6, P=0.004). These three factors remained independently predictive of adverse outcome after multivariable adjustment: factor 2 (adjusted hazard ratio 1.23; 95% confidence interval [1.10-1.38]; P<0.001), factor 5 (1.17 [1.01-1.37], P=0.04), and factor 6 (1.14 [1.02-1.27], P=0.03). Conclusions Metabolic profiles are independently associated with adverse outcomes following coronary artery bypass grafting. These profiles may represent novel biomarkers of risk that augment existing tools for risk stratification of coronary artery bypass grafting patients and may elucidate novel biochemical pathways that mediate risk. PMID:22306227

  1. Model for Estimating the Threshold Mechanical Stability of Structural Cartilage Grafts Used in Rhinoplasty

    PubMed Central

    Zemek, Allison; Garg, Rohit; Wong, Brian J. F.

    2014-01-01

    Objectives/Hypothesis Characterizing the mechanical properties of structural cartilage grafts used in rhinoplasty is valuable because softer engineered tissues are more time- and cost-efficient to manufacture. The aim of this study is to quantitatively identify the threshold mechanical stability (e.g., Young’s modulus) of columellar, L-strut, and alar cartilage replacement grafts. Study Design Descriptive, focus group survey. Methods Ten mechanical phantoms of identical size (5 × 20 × 2.3 mm) and varying stiffness (0.360 to 0.85 MPa in 0.05 MPa increments) were made from urethane. A focus group of experienced rhinoplasty surgeons (n = 25, 5 to 30 years in practice) were asked to arrange the phantoms in order of increasing stiffness. Then, they were asked to identify the minimum acceptable stiffness that would still result in favorable surgical outcomes for three clinical applications: columellar, L-strut, and lateral crural replacement grafts. Available surgeons were tested again after 1 week to evaluate intra-rater consistency. Results For each surgeon, the threshold stiffness for each clinical application differed from the threshold values derived by logistic regression by no more than 0.05 MPa (accuracy to within 10%). Specific thresholds were 0.56, 0.59, and 0.49 MPa for columellar, L-strut, and alar grafts, respectively. For comparison, human nasal septal cartilage is approximately 0.8 MPa. Conclusions There was little inter- and intra-rater variation of the identified threshold values for adequate graft stiffness. The identified threshold values will be useful for the design of tissue-engineered or semisynthetic cartilage grafts for use in structural nasal surgery. PMID:20513022

  2. Tissue engineering of peripheral nerves: Epineurial grafts with application of cultured Schwann cells.

    PubMed

    Fansa, H; Dodic, T; Wolf, G; Schneider, W; Keilhoff, G

    2003-01-01

    After a simple nerve lesion, primary microsurgical suture is the treatment of choice. A nerve gap has to be bridged, with a nerve graft sacrificing a functioning nerve. Alternatively, tissue engineering of nerve grafts has become a subject of experimental research. It is evident that nerve regeneration requires not only an autologous, allogenous, or biodegradable scaffold, but additional interactions with regeneration-promoting Schwann cells. In this study, we compared epineurial and acellularized epineurial tubes with and without application of cultured Schwann cells as alternative grafts in a rat sciatic nerve model. Autologous nerve grafts served as controls. Evaluation was performed after 6 weeks; afterwards, sections of the graft and distal nerve were harvested for histological and morphometrical analysis. Compared to controls, all groups showed a significantly lower number of axons, less well-shaped remyelinizated axons, and a delay in clinical recovery (e.g., toe spread). The presented technique with application of Schwann cells into epineurial tubes did not offer any major advantages for nerve regeneration. Thus, in this applied model, neither the implantation of untreated nor the implantation of acellularized epineurial tubes with cultured Schwann cells to bridge nerve defects was capable of presenting a serious alternative to the present gold standard of conventional nerve grafts for bridging nerve defects in this model. Copyright 2003 Wiley-Liss, Inc.

  3. Biodegradability of poly(3-hydroxybutyrate) film grafted with vinyl acetate: Effect of grafting and saponification

    NASA Astrophysics Data System (ADS)

    Wada, Yuki; Seko, Noriaki; Nagasawa, Naotsugu; Tamada, Masao; Kasuya, Ken-ichi; Mitomo, Hiroshi

    2007-06-01

    Radiation-induced graft polymerization of vinyl acetate (VAc) onto poly(3-hydroxybutyrate) (PHB) film was carried out. At a degree of grafting higher than 5%, the grafted films (PHB-g-VAc) completely lost the enzymatic degradability that is characteristic of PHB due to the grafted VAc covering the surface of the PHB film. However, the biodegradability of the PHB-g-VAc films was recovered when the films were saponified in alkali solution under optimum conditions. Graft chains of the PHB-g-VAc film reacted selectively to become biodegradable polyvinyl alcohol (PVA). The biodegradability of the saponified PHB-g-VAc film increased rapidly with time.

  4. Causes of corneal graft failure in India.

    PubMed

    Dandona, L; Naduvilath, T J; Janarthanan, M; Rao, G N

    1998-09-01

    The success of corneal grafting in visual rehabilitation of the corneal blind in India depends on survival of the grafts. Understanding the causes of graft failure may help reduce the risk of failure. We studied these causes in a series of 638 graft failures at our institution. Multivariate logistic regression analysis was used to evaluate the association of particular causes of graft failure with indications for grafting, socioeconomic status, age, sex, host corneal vascularization, donor corneal quality, and experience of surgeon. The major causes of graft failure were allograft rejection (29.2%), increased intraocular pressure (16.9%), infection excluding endophthalmitis (15.4%), and surface problems (12.7%). The odds of infection causing graft failure were significantly higher in patients of lower socioeconomic status (odds ratio 2.45, 95% CI 1.45-4.15). Surface problems as a cause of graft failure was significantly associated with grafts done for corneal scarring or for regrafts (odds ratio 3.36, 95% CI 1.80-6.30). Increased intraocular pressure as a cause of graft failure had significant association with grafts done for aphakic or pseudophakic bullous keratopathy, congenital conditions or glaucoma, or regrafts (odds ratio 2.19, 95% CI 1.25-3.84). Corneal dystrophy was the indication for grafting in 12 of the 13 cases of graft failure due to recurrence of host disease. Surface problems, increased intraocular pressure, and infection are modifiable risk factors that are more likely to cause graft failure in certain categories of patients in India. Knowledge about these associations can be helpful in looking for and aggressively treating these modifiable risk factors in the at-risk categories of corneal graft patients. This can possibly reduce the chance of graft failure.

  5. Adipose-Derived Mesenchymal Stem Cell Administration Does Not Improve Corneal Graft Survival Outcome

    PubMed Central

    Fuentes-Julián, Sherezade; Arnalich-Montiel, Francisco; Jaumandreu, Laia; Leal, Marina; Casado, Alfonso; García-Tuñon, Ignacio; Hernández-Jiménez, Enrique; López-Collazo, Eduardo; De Miguel, Maria P.

    2015-01-01

    The effect of local and systemic injections of mesenchymal stem cells derived from adipose tissue (AD-MSC) into rabbit models of corneal allograft rejection with either normal-risk or high-risk vascularized corneal beds was investigated. The models we present in this study are more similar to human corneal transplants than previously reported murine models. Our aim was to prevent transplant rejection and increase the length of graft survival. In the normal-risk transplant model, in contrast to our expectations, the injection of AD-MSC into the graft junction during surgery resulted in the induction of increased signs of inflammation such as corneal edema with increased thickness, and a higher level of infiltration of leukocytes. This process led to a lower survival of the graft compared with the sham-treated corneal transplants. In the high-risk transplant model, in which immune ocular privilege was undermined by the induction of neovascularization prior to graft surgery, we found the use of systemic rabbit AD-MSCs prior to surgery, during surgery, and at various time points after surgery resulted in a shorter survival of the graft compared with the non-treated corneal grafts. Based on our results, local or systemic treatment with AD-MSCs to prevent corneal rejection in rabbit corneal models at normal or high risk of rejection does not increase survival but rather can increase inflammation and neovascularization and break the innate ocular immune privilege. This result can be partially explained by the immunomarkers, lack of immunosuppressive ability and immunophenotypical secretion molecules characterization of AD-MSC used in this study. Parameters including the risk of rejection, the inflammatory/vascularization environment, the cell source, the time of injection, the immunosuppression, the number of cells, and the mode of delivery must be established before translating the possible benefits of the use of MSCs in corneal transplants to clinical practice. PMID

  6. Clinical and radiological outcomes after a quasi-anatomical reconstruction of medial patellofemoral ligament with gracilis tendon autograft.

    PubMed

    Monllau, Joan C; Masferrer-Pino, Àngel; Ginovart, Gerard; Pérez-Prieto, Daniel; Gelber, Pablo E; Sanchis-Alfonso, Vicente

    2017-08-01

    To analyse the clinical and radiological outcomes of a quasi-anatomical reconstruction of the medial patellofemoral ligament (MPFL) with a gracilis tendon autograft. Patients with objective recurrent patellar instability that were operated on from 2006 to 2012 were included. A quasi-anatomical surgical technique was performed using a gracilis tendon autograft. It was anatomically attached at the patella, and the adductor magnus tendon was also used as a pulley for femoral fixation (non-anatomical reconstruction). The IKDC, Kujala and Lysholm scores as well as Tegner and VAS for pain were collected preoperatively and at final follow-up. Radiographic measurements of patellar position tilt and signs of osteoarthritis (OA) as well as trochlear dysplasia were also recorded. Thirty-six patients were included. The mean age at surgery was 25.6 years. After a minimum 27 months of follow-up, all functional scores significantly improved (p < 0.001) with respect to the preoperative values. The VAS dropped from 6 (SD 2.48) to 2 (SD 1.58). No recurrence of dislocation was observed in this series. The apprehension sign was still apparent in one patient. The CT scan evaluation showed a significant decrease in patellar tilt (p < 0.001). On the Crosby and Insall grading scale, there were no changes in the radiological signs of OA. This specific MPFL reconstruction gives good clinical results and corrects patellar tilt. It did not affect the patellofemoral surfaces at the short term, as shown by the absence of radiological signs of OA in the CT scan. The procedure has been shown to be safe and suitable for the treatment of chronic patellar instability, including in adolescents with open physis. A new effective, inexpensive and easy-to-perform technique is described to reconstruct MPFL in the daily clinical practice. Therapeutic case series, Level IV.

  7. Plant grafting: insights into tissue regeneration.

    PubMed

    Melnyk, Charles W

    2017-02-01

    For millennia, people have cut and joined different plants together through a process known as grafting. The severed tissues adhere, the cells divide and the vasculature differentiates through a remarkable process of regeneration between two genetically distinct organisms as they become one. Grafting is becoming increasingly important in horticulture where it provides an efficient means for asexual propagation. Grafting also combines desirable roots and shoots to generate chimeras that are more vigorous, more pathogen resistant and more abiotic stress resistant. Thus, it presents an elegant and efficient way to improve plant productivity in vegetables and trees using traditional techniques. Despite this horticultural importance, we are only beginning to understand how plants regenerate tissues at the graft junction. By understanding grafting better, we can shed light on fundamental regeneration pathways and the basis for self/non-self recognition. We can also better understand why many plants efficiently graft whereas others cannot, with the goal of improving grafting so as to broaden the range of grafted plants to create even more desirable chimeras. Here, I review the latest findings describing how plants graft and provide insight into future directions in this emerging field.

  8. Grafting: A Technique to Modify Ion Accumulation in Horticultural Crops

    PubMed Central

    Nawaz, Muhammad A.; Imtiaz, Muhammad; Kong, Qiusheng; Cheng, Fei; Ahmed, Waqar; Huang, Yuan; Bie, Zhilong

    2016-01-01

    studies have focused on model and non-grafted plants, and information on grafted plants is limited. Such information will improve the development of nutrient-efficient rootstocks. PMID:27818663

  9. An acellular dermal matrix allograft (Alloderm®) for increasing keratinized attached gingiva: A case series

    PubMed Central

    Agarwal, Chitra; Kumar, Baron Tarun; Mehta, Dhoom Singh

    2015-01-01

    Context: Adequate amount of keratinized gingiva is necessary to keep gingiva healthy and free of inflammation. Autografts have been used for years with great success to increase the width of attached gingiva. Autografts, however, have the disadvantage of increasing postoperative morbidity and improper color match with the adjacent tissues. Alloderm® allograft has been introduced as an alternative to autografts to overcome these disadvantages. Aim: In this study, the efficacy of alloderm® in increasing the width of attached gingiva and the stability of gained attached gingiva was evaluated clinically. Materials and Methods: Five patients with sites showing inadequate width of attached gingiva (≤1 mm) were enrolled for the study. The width of keratinized gingiva and other clinical parameters were recorded at baseline and 9th month postoperatively. Result: In all cases, there is the average increase of about 2.5 mm of attached gingiva and was maintained for 9-month. Percentage shrinkage of the graft is about 75% at the end of 3rd month in all cases. Excellent colors match with adjacent tissue has been obtained. Conclusion: The study signifies that Alloderm® results in an adequate increase in the amount of attached gingiva and therefore can be used successfully in place of autografts. PMID:26015676

  10. Mild anastomotic stenosis in patient-specific CABG model may enhance graft patency: a new hypothesis.

    PubMed

    Huo, Yunlong; Luo, Tong; Guccione, Julius M; Teague, Shawn D; Tan, Wenchang; Navia, José A; Kassab, Ghassan S

    2013-01-01

    It is well known that flow patterns at the anastomosis of coronary artery bypass graft (CABG) are complex and may affect the long-term patency. Various attempts at optimal designs of anastomosis have not improved long-term patency. Here, we hypothesize that mild anastomotic stenosis (area stenosis of about 40-60%) may be adaptive to enhance the hemodynamic conditions, which may contribute to slower progression of atherosclerosis. We further hypothesize that proximal/distal sites to the stenosis have converse changes that may be a risk factor for the diffuse expansion of atherosclerosis from the site of stenosis. Twelve (12) patient-specific models with various stenotic degrees were extracted from computed tomography images using a validated segmentation software package. A 3-D finite element model was used to compute flow patterns including wall shear stress (WSS) and its spatial and temporal gradients (WSS gradient, WSSG, and oscillatory shear index, OSI). The flow simulations showed that mild anastomotic stenosis significantly increased WSS (>15 dynes · cm(-2)) and decreased OSI (<0.02) to result in a more uniform distribution of hemodynamic parameters inside anastomosis albeit proximal/distal sites to the stenosis have a decrease of WSS (<4 dynes · cm(-2)). These findings have significant implications for graft adaptation and long-term patency.

  11. Decreasing Skin Graft Contraction through Topical Wound Bed Preparation with Anti-Inflammatory Agents

    DTIC Science & Technology

    2015-10-01

    This proposal aims to identify topically applied anti-inflammatory drugs that will reduce recipient site inflammation and skin graft contraction. We...hypothesize that the elevated and prolonged inflammatory state of the recipient wound bed is a causative factor in the development of skin graft contraction...Using a porcine model of skin graft contraction, we will screen for anti-inflammatory agents (dose, schedule of administration, drug class

  12. Graft union formation in Douglas-fir.

    Treesearch

    D.L. Copes

    1969-01-01

    Greenhouse-grown Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) graft unions were examined between 2 and 84 days after grafting. Room temperature was maintained at 60-70 F throughout the growing season. In most respects grafts of Douglas-fir followed development patterns previously reported for spruce and pine grafts, but specific differences...

  13. Immobilized enzymes in blood plasma exchangers via radiation grafting

    NASA Astrophysics Data System (ADS)

    Gombotz, Wayne; Hoffman, Allan; Schmer, Gottfried; Uenoyama, Satoshi

    The enzyme asparaginase was immobilized onto a porous hollow polypropylene (PP) fiber blood plasma exchange device for the treatment of acute lymphocytic leukemia. The devices were first radiation grafted with polymethacrylic acid (poly(MAAc)). This introduces carboxyl groups onto the surface of the fibers. Several variables were studied in the grafting reaction including the effects of solvent type and monomer concentration. The carboxyl groups were activated with N-hydroxy succinimide (NHS) using carbodiimide chemistry. Asparaginase was then covalently immobilized on the activated surfaces. Quantitative relationships were found relating the percent graft to the amount of immobilized enzyme which was active. The enzyme reactor was tested both in vitro and in vivo using a sheep as an animal model.

  14. Automatic segmentation of the wire frame of stent grafts from CT data.

    PubMed

    Klein, Almar; van der Vliet, J Adam; Oostveen, Luuk J; Hoogeveen, Yvonne; Kool, Leo J Schultze; Renema, W Klaas Jan; Slump, Cornelis H

    2012-01-01

    Endovascular aortic replacement (EVAR) is an established technique, which uses stent grafts to treat aortic aneurysms in patients at risk of aneurysm rupture. Late stent graft failure is a serious complication in endovascular repair of aortic aneurysms. Better understanding of the motion characteristics of stent grafts will be beneficial for designing future devices. In addition, analysis of stent graft movement in individual patients in vivo can be valuable for predicting stent graft failure in these patients. To be able to gather information on stent graft motion in a quick and robust fashion, we propose an automatic method to segment stent grafts from CT data, consisting of three steps: the detection of seed points, finding the connections between these points to produce a graph, and graph processing to obtain the final geometric model in the form of an undirected graph. Using annotated reference data, the method was optimized and its accuracy was evaluated. The experiments were performed using data containing the AneuRx and Zenith stent grafts. The algorithm is robust for noise and small variations in the used parameter values, does not require much memory according to modern standards, and is fast enough to be used in a clinical setting (65 and 30s for the two stent types, respectively). Further, it is shown that the resulting graphs have a 95% (AneuRx) and 92% (Zenith) correspondence with the annotated data. The geometric model produced by the algorithm allows incorporation of high level information and material properties. This enables us to study the in vivo motions and forces that act on the frame of the stent. We believe that such studies will provide new insights into the behavior of the stent graft in vivo, enables the detection and prediction of stent failure in individual patients, and can help in designing better stent grafts in the future. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. A Mathematical Model to Predict Endothelial Cell Density Following Penetrating Keratoplasty With Selective Dropout From Graft Failure

    PubMed Central

    Riddlesworth, Tonya D.; Kollman, Craig; Lass, Jonathan H.; Patel, Sanjay V.; Stulting, R. Doyle; Benetz, Beth Ann; Gal, Robin L.; Beck, Roy W.

    2014-01-01

    Purpose. We constructed several mathematical models that predict endothelial cell density (ECD) for patients after penetrating keratoplasty (PK) for a moderate-risk condition (principally Fuchs' dystrophy or pseudophakic/aphakic corneal edema). Methods. In a subset (n = 591) of Cornea Donor Study participants, postoperative ECD was determined by a central reading center. Various statistical models were considered to estimate the ECD trend longitudinally over 10 years of follow-up. A biexponential model with and without a logarithm transformation was fit using the Gauss-Newton nonlinear least squares algorithm. To account for correlated data, a log-polynomial model was fit using the restricted maximum likelihood method. A sensitivity analysis for the potential bias due to selective dropout was performed using Bayesian analysis techniques. Results. The three models using a logarithm transformation yield similar trends, whereas the model without the transform predicts higher ECD values. The adjustment for selective dropout turns out to be negligible. However, this is possibly due to the relatively low rate of graft failure in this cohort (19% at 10 years). Fuchs' dystrophy and pseudophakic/aphakic corneal edema (PACE) patients had similar ECD decay curves, with the PACE group having slightly higher cell densities by 10 years. Conclusions. Endothelial cell loss after PK can be modeled via a log-polynomial model, which accounts for the correlated data from repeated measures on the same subject. This model is not significantly affected by the selective dropout due to graft failure. Our findings warrant further study on how this may extend to ECD following endothelial keratoplasty. PMID:25425307

  16. Neural Stem Cell or Human Induced Pluripotent Stem Cell-derived GABA-ergic Progenitor Cell Grafting in an Animal Model of Chronic Temporal Lobe Epilepsy

    PubMed Central

    Upadhya, Dinesh; Hattiangady, Bharathi; Shetty, Geetha A.; Zanirati, Gabriele; Kodali, Maheedhar; Shetty, Ashok K.

    2016-01-01

    Grafting of neural stem cells (NSCs) or GABA-ergic progenitor cells (GPCs) into the hippocampus could offer an alternative therapy to hippocampal resection in patients with drug-resistant chronic epilepsy, which afflicts >30% of temporal lobe epilepsy (TLE) cases. Multipotent, self-renewing NSCs could be expanded from multiple regions of the developing and adult brain, human embryonic stem cells (hESCs), and human induced pluripotent stem cells (hiPSCs). On the other hand, GPCs could be generated from the medial and lateral ganglionic eminences of the embryonic brain and from hESCs and hiPSCs. To provide comprehensive methodologies involved in testing the efficacy of transplantation of NSCs and GPCs in a rat model of chronic TLE, NSCs derived from the rat medial ganglionic eminence (MGE) and MGE-like GPCs derived from hiPSCs are taken as examples in this unit. The topics comprise description of the required materials, reagents and equipment, methods for obtaining rat MGE-NSCs and hiPSC-derived MGE-like GPCs in culture, generation of chronically epileptic rats, intrahippocampal grafting procedure, post-grafting evaluation of the effects of grafts on spontaneous recurrent seizures and cognitive and mood impairments, analyses of the yield and the fate of graft-derived cells, and the effects of grafts on the host hippocampus. PMID:27532817

  17. Comparison of endothelial function of coronary artery bypass grafts in diabetic and nondiabetic patients: Which graft offers the best?

    PubMed Central

    Gür, Demet Özkaramanlı; Gür, Özcan; Gürkan, Selami; Cömez, Selcem; Gönültaş, Aylin; Yılmaz, Murat

    2016-01-01

    Objective: Diabetes associated endothelial dysfunction, which determines both long and short term graft patency, is not uniform in all coronary artery bypass surgery (CABG) grafts. Herein this study, we aimed to investigate the degree of endothelial dysfunction in diabetic radial artery (RA), internal mammarian artery (IMA) and saphenous vein (SV) grafts in vitro tissue bath system. Methods: This is a prospective experimental study. Fifteen diabetic and 15 non-diabetic patients were included to the study. A total number of 96 graft samples were collected; 16 graft samples for each graft type from both diabetic and non-diabetic patients. Arterial grafts were harvested with pedicles and SV grafts were harvested by ‘no touch’ technique. Vasodilatation response of vascular rings to carbachol, which induces nitric oxide (NO) mediated vasodilatation, was designated as the measure of endothelial function. Results: The IMA grafts had the most prominent NO mediated vasodilatation in both diabetic and non-diabetic patients, concluding a better preserved endothelial function than SV and RA. The ‘no-touch’ SV and RA grafts had similar vasodilatation responses in non-diabetic patients. In diabetic patients, on the other hand, RA grafts exhibited the least vasodilatation response (ie. worst endothelial function), even less vasodilatation than ‘no touch’ SV grafts (p<0.0001). Conclusion: Deteriorated function of RA grafts in diabetic patients, even worse than SV grafts made evident by this study, encourages the use of ‘no touch’ technique as the method of SV harvesting and more meticulous imaging of RA before its use as a graft in diabetic patients. PMID:26301347

  18. Effects of initial graft tension on femoral tunnel widening after anatomic anterior cruciate ligament reconstruction using a bone-patellar tendon-bone graft.

    PubMed

    Taketomi, Shuji; Inui, Hiroshi; Tahara, Keitaro; Shirakawa, Nobuyuki; Tanaka, Sakae; Nakagawa, Takumi

    2017-09-01

    The effects of initial graft tension upon tunnel widening (TW) following anatomic anterior cruciate ligament (ACL) reconstruction have not been elucidated. The purpose of this study was to retrospectively investigate the effect of two different graft-tensioning protocols upon femoral TW following anatomic ACL reconstruction using a bone-patellar tendon-bone (BPTB) graft and a three-dimensional (3D) computed tomography (CT) model. Forty-three patients who underwent isolated ACL reconstruction using BPTB grafts were included in this study. In 18 out of the 43 patients, the graft was fixed at full knee extension with manual maximum pull (Group H). These patients were compared with 25 patients in whom the BPTB graft was fixed at full knee extension with 80-N pull (Group L). Tunnel aperture area was measured using 3D CT 1 week and 1 year postoperatively, thus enabling us to calculate the percentage change in the area of femoral tunnel aperture. Clinical assessment was performed 1 year postoperatively, corresponding to the time period of CT assessment, and involved the evaluation of Lysholm score, anterior knee stability using a KneeLax3 arthrometer, and the pivot-shift test. When measured at 1 year postoperatively, the mean area of the femoral tunnel aperture had increased by 78.6 ± 36.8% in Group H when compared with at 1 week postoperatively, whereas that of Group L had increased by 27.7 ± 32.3%. Furthermore, TW (%) in Group H was significantly greater than that of Group L (P < 0.001). No significant differences were detected between the two groups with regard to any of the clinical outcomes evaluated. High levels of initial graft tension resulted in greater TW of the femoral tunnel aperture following anatomical ACL reconstruction using BPTB grafts. However, such levels of graft tension did not affect clinical outcome.

  19. Steric and electrostatic surface forces on sulfonated PEG graft surfaces with selective albumin adsorption.

    PubMed

    Bremmell, Kristen E; Britcher, Leanne; Griesser, Hans J

    2013-06-01

    Addition of ionized terminal groups to PEG graft layers may cause additional interfacial forces to modulate the net interfacial interactions between PEG graft layers and proteins. In this study we investigated the effect of terminal sulfonate groups, characterizing PEG-aldehyde (PEG-CHO) and sulfonated PEG (PEG-SO3) graft layers by XPS and colloid probe AFM interaction force measurements as a function of ionic strength, in order to determine surface forces relevant to protein resistance and models of bio-interfacial interaction of such graft coatings. On the PEG-CHO surface the measured interaction force does not alter with ionic strength, typical of a repulsive steric barrier coating. An analogous repulsive interaction force of steric origin was also observed on the PEG-SO3 graft coating; however, the net interaction force changed with ionic strength. Interaction forces were modelled by steric and electrical double layer interaction theories, with fitting to a scaling theory model enabling determination of the spacing and stretching of the grafted chains. Albumin, fibrinogen, and lysozyme did not adsorb on the PEG-CHO coating, whereas the PEG graft with terminal sulfonate groups showed substantial adsorption of albumin but not fibrinogen or lysozyme from 0.15 M salt solutions. Under lower ionic strength conditions albumin adsorption was again minimized as a result of the increased electrical double-layer interaction observed with the PEG-SO3 modified surface. This unique and unexpected adsorption behaviour of albumin provides an alternative explanation to the "negative cilia" model used by others to rationalize observed thromboresistance on PEG-sulfonate coatings. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Modeling polymer-induced interactions between two grafted surfaces: comparison between interfacial statistical associating fluid theory and self-consistent field theory.

    PubMed

    Jain, Shekhar; Ginzburg, Valeriy V; Jog, Prasanna; Weinhold, Jeffrey; Srivastava, Rakesh; Chapman, Walter G

    2009-07-28

    The interaction between two polymer grafted surfaces is important in many applications, such as nanocomposites, colloid stabilization, and polymer alloys. In our previous work [Jain et al., J. Chem. Phys. 128, 154910 (2008)], we showed that interfacial statistical associating fluid density theory (iSAFT) successfully calculates the structure of grafted polymer chains in the absence/presence of a free polymer. In the current work, we have applied this density functional theory to calculate the force of interaction between two such grafted monolayers in implicit good solvent conditions. In particular, we have considered the case where the segment sizes of the free (sigma(f)) and grafted (sigma(g)) polymers are different. The interactions between the two monolayers in the absence of the free polymer are always repulsive. However, in the presence of the free polymer, the force either can be purely repulsive or can have an attractive minimum depending upon the relative chain lengths of the free (N(f)) and grafted polymers (N(g)). The attractive minimum is observed only when the ratio alpha = N(f)/N(g) is greater than a critical value. We find that these critical values of alpha satisfy the following scaling relation: rho(g) square root(N(g)) beta(3) proportional to alpha(-lambda), where beta = sigma(f)/sigma(g) and lambda is the scaling exponent. For beta = 1 or the same segment sizes of the free and grafted polymers, this scaling relation is in agreement with those from previous theoretical studies using self-consistent field theory (SCFT). Detailed comparisons between iSAFT and SCFT are made for the structures of the monolayers and their forces of interaction. These comparisons lead to interesting implications for the modeling of nanocomposite thermodynamics.

  1. Novel expansion techniques for skin grafts

    PubMed Central

    Kadam, Dinesh

    2016-01-01

    The quest for skin expansion is not restricted to cover a large area alone, but to produce acceptable uniform surfaces, robust engraftment to withstand mechanical shear and infection, with a minimal donor morbidity. Ease of the technique, shorter healing period and reproducible results are essential parameters to adopt novel techniques. Significant advances seen in four fronts of autologous grafting are: (1) Dermal–epidermal graft expansion techniques, (2) epidermal graft harvests technique, (3) melanocyte-rich basal cell therapy for vitiligo and (4) robust and faster autologous cell cultures. Meek's original concept that the sum of perimeter of smaller grafts is larger than the harvested graft, and smaller the graft size, the greater is the potential for regeneration is witnessed in newer modification. Further, as graft size becomes smaller or minced, these micrografts can survive on the wound bed exudate irrespective of their dermal orientation. Expansion produced by 4 mm × 4 mm sized Meek micrografts is 10-folds, similarly 0.8 mm × 0.8 mm size micrografts produce 100-fold expansion, which becomes 700-fold with pixel grafts of 0.3 mm × 0.3 mm size. Fractional skin harvest is another new technique with 700 μ size full thickness graft. These provide instant autologous non-cultured graft to cover extensive areas with similar quality of engraftment surface as split skin grafts. Newer tools for epidermal blister graft harvest quickly, with uniform size to produce 7-fold expansions with reproducible results. In addition, donor area heals faster with minimal scar. Melanocyte-rich cell suspension is utilised in vitiligo surgery tapping the potential of hair root melanocytes. Further advances in the cell culture to reduce the cultivation time and provide stronger epidermal sheets with dermal carrier are seen in trials. PMID:27274117

  2. Allografts with autogenous platelet-rich plasma for tibial defect reconstruction: a rabbit study.

    PubMed

    Nather, Aziz; Wong, Keng Lin; David, Vikram; Pereira, Barry P

    2012-12-01

    To evaluate the effect of autogenous platelet-rich plasma (PRP) for fresh-frozen allografts in tibial defect reconstruction in rabbits. 40 adult New Zealand white rabbits underwent tibial defect reconstruction with autografts (n=12), allografts without PRP (n=12), or allografts with PRP (n=12) and were observed for 12, 16, and 24 weeks (4 for each period). Tibias of the remaining 4 rabbits were used as donor allografts, and the remaining allografts were procured from recipient rabbits. A 1.5- cm cortical segment of the tibia was osteotomised, and then fixed with a 9-hole mini-compression plate and 2 cerclage wires. Allografts were stripped off the periosteum and soft tissues and medullary contents, and then stored in a freezer at -80 ºC. All allografts were deep frozen for at least 4 weeks before transplantation. 7 ml of whole blood was drawn to prepare 1 ml of PRP. The PRP was then mixed with 1.0 ml of human thrombin to form a platelet gel. The PRP gel was then packed into the medullary canal of the allograft and applied on the cortical surface before tibial defect reconstruction. Rabbits were sacrificed at 12, 16, and 24 weeks. The specimens were assessed for bone union at host-graft junctions and for bone resorption, new bone formation, callus encasement, and viable osteocyte counts. There were 4 specimens in each group at each observation period. Osteoid bridging the gap at host-graft junctions was noted in all specimens in the autograft and allograft-with-PRP groups at week 12 and in the allograft-without-PRP group at week 24. Bone union in allografts without PRP was delayed. All indices for biological incorporation (resorption index, new bone formation index, callus encasement index, and viable osteocyte count) were significantly greater in the autograft than allograft-without-PRP groups, except for the resorption index at week 24, whereas the differences were not significant between the autograft and allograft-with-PRP groups. The differences between the 2

  3. The effect of mesenchymal stem cell sheets on structural allograft healing of critical-sized femoral defects in mice

    PubMed Central

    Long, Teng; Zhu, Zhenan; Awad, Hani A.; Schwarz, Edward M.; Hilton, Matthew J.; Dong, Yufeng

    2014-01-01

    Structural bone allografts are widely used in the clinic to treat critical sized bone defects, despite lacking the osteoinductive characteristics of live autografts. To address this, we generated revitalized structural allografts wrapped with mesenchymal stem/progenitor cell (MSC) sheets, which were produced by expanding primary syngenic bone marrow derived cells on temperature-responsive plates, as a tissue engineered periosteum. In vitro assays demonstrated maintenance of the MSC phenotype in the sheets, suggesting that short-term culturing of MSC sheets is not detrimental. To test their efficacy in vivo, allografts wrapped with MSC sheets were transplanted into 4-mm murine femoral defects and compared to allografts with direct seeding of MSCs and allografts without cells. Evaluations consisted of x-ray plain radiography, 3D microCT, histology, and biomechanical testing at 4- and 6-weeks post-surgery. Our findings demonstrate that MSC sheets induce prolonged cartilage formation at the graft-host junction and enhanced bone callus formation, as well as graft-host osteointegration. Moreover, a large periosteal callus was observed spanning the allografts with MSC sheets, which partially mimics live autograft healing. Finally, biomechanical testing showed a significant increase in the structural and functional properties of MSC sheet grafted femurs. Taken together, MSC sheets exhibit enhanced osteogenicity during critical sized bone defect repair, demonstrating the feasibility of this tissue engineering solution for massive allograft healing. PMID:24393269

  4. Outcomes Using Grafts from Donors after Cardiac Death.

    PubMed

    Doyle, M B Majella; Collins, Kelly; Vachharajani, Neeta; Lowell, Jeffrey A; Shenoy, Surendra; Nalbantoglu, Ilke; Byrnes, Kathleen; Garonzik-Wang, Jacqueline; Wellen, Jason; Lin, Yiing; Chapman, William C

    2015-07-01

    Previous reports suggest that donation after cardiac death (DCD) liver grafts have increased primary nonfunction (PNF) and cholangiopathy thought to be due to the graft warm ischemia before cold flushing. In this single-center, retrospective study, 866 adult liver transplantations were performed at our institution from January 2005 to August 2014. Forty-nine (5.7%) patients received DCD donor grafts. The 49 DCD graft recipients were compared with all recipients of donation after brain death donor (DBD) grafts and to a donor and recipient age- and size-matched cohort. The DCD donors were younger (age 28, range 8 to 60 years) than non-DCD (age 44.3, range 9 to 80 years) (p < 0.0001), with similar recipient age. The mean laboratory Model for End-Stage Liver Disease (MELD) was lower in DCD recipients (18.7 vs 22.2, p = 0.03). Mean cold and warm ischemia times were similar. Median ICU and hospital stay were 2 days and 7.5 days in both groups (p = 0.37). Median follow-ups were 4.0 and 3.4 years, respectively. Long-term outcomes were similar between groups, with similar 1-, 3- and 5-year patient and graft survivals (p = 0.59). Four (8.5%) recipients developed ischemic cholangiopathy (IC) at 2, 3, 6, and 8 months. Primary nonfunction and hepatic artery thrombosis did not occur in any patient in the DCD group. Acute kidney injury was more common with DCD grafts (16.3% of DCD recipients required dialysis vs 4.1% of DBD recipients, p = 0.01). An increased donor age (>40 years) was shown to increase the risk of IC (p = 0.006). Careful selection of DCD donors can provide suitable donors, with results of liver transplantation comparable to those with standard brain dead donors. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  5. Three-dimensional computer-aided human factors engineering analysis of a grafting robot.

    PubMed

    Chiu, Y C; Chen, S; Wu, G J; Lin, Y H

    2012-07-01

    The objective of this research was to conduct a human factors engineering analysis of a grafting robot design using computer-aided 3D simulation technology. A prototype tubing-type grafting robot for fruits and vegetables was the subject of a series of case studies. To facilitate the incorporation of human models into the operating environment of the grafting robot, I-DEAS graphic software was applied to establish individual models of the grafting robot in line with Jack ergonomic analysis. Six human models (95th percentile, 50th percentile, and 5th percentile by height for both males and females) were employed to simulate the operating conditions and working postures in a real operating environment. The lower back and upper limb stresses of the operators were analyzed using the lower back analysis (LBA) and rapid upper limb assessment (RULA) functions in Jack. The experimental results showed that if a leg space is introduced under the robot, the operator can sit closer to the robot, which reduces the operator's level of lower back and upper limbs stress. The proper environmental layout for Taiwanese operators for minimum levels of lower back and upper limb stress are to set the grafting operation at 23.2 cm away from the operator at a height of 85 cm and with 45 cm between the rootstock and scion units.

  6. Retransplantation in Late Hepatic Artery Thrombosis: Graft Access and Transplant Outcome.

    PubMed

    Buchholz, Bettina M; Khan, Shakeeb; David, Miruna D; Gunson, Bridget K; Isaac, John R; Roberts, Keith J; Muiesan, Paolo; Mirza, Darius F; Tripathi, Dhiraj; Perera, M Thamara P R

    2017-08-01

    Definitive treatment for late hepatic artery thrombosis (L-HAT) is retransplantation (re-LT); however, the L-HAT-associated disease burden is poorly represented in allocation models. Graft access and transplant outcome of the re-LT experience between 2005 and 2016 was reviewed with specific focus on the L-HAT cohort in this single-center retrospective study. Ninety-nine (5.7%) of 1725 liver transplantations were re-LT with HAT as the main indication (n = 43; 43%) distributed into early (n = 25) and late (n = 18) episodes. Model for end-stage liver disease as well as United Kingdom model for end-stage liver disease did not accurately reflect high disease burden of graft failure associated infections such as hepatic abscesses and biliary sepsis in L-HAT. Hence, re-LT candidates with L-HAT received low prioritization and waited longest until the allocation of an acceptable graft (median, 103 days; interquartile range, 28-291 days), allowing for progression of biliary sepsis. Balance of risk score and 3-month mortality score prognosticated good transplant outcome in L-HAT but, contrary to the prediction, the factual 1-year patient survival after re-LT was significantly inferior in L-HAT compared to early HAT, early non-HAT and late non-HAT (65% vs 82%, 92% and 95%) which was mainly caused by sepsis and multiorgan failure driving 3-month mortality (28% vs 11%, 16% and 0%). Access to a second graft after a median waitlist time of 6 weeks achieved the best short- and long-term outcome in re-LT for L-HAT (3-month mortality, 13%; 1-year survival, 77%). Inequity in graft access and peritransplant sepsis are fundamental obstacles for successful re-LT in L-HAT. Offering a graft for those in need at the best window of opportunity could facilitate earlier engrafting with improved outcomes.

  7. Keratocyte Apoptosis and Not Myofibroblast Differentiation Mark the Graft/Host Interface at Early Time-Points Post-DSAEK in a Cat Model

    PubMed Central

    Weis, Adam J.; Huxlin, Krystel R.; Callan, Christine L.; DeMagistris, Margaret A.; Hindman, Holly B.

    2013-01-01

    Purpose To evaluate myofibroblast differentiation as an etiology of haze at the graft-host interface in a cat model of Descemet’s Stripping Automated Endothelial Keratoplasty (DSAEK). Methods DSAEK was performed on 10 eyes of 5 adult domestic short-hair cats. In vivo corneal imaging with slit lamp, confocal, and optical coherence tomography (OCT) were performed twice weekly. Cats were sacrificed and corneas harvested 4 hours, and 2, 4, 6, and 9 days post-DSAEK. Corneal sections were stained with the TUNEL method and immunohistochemistry was performed for α-smooth muscle actin (α-SMA) and fibronectin with DAPI counterstain. Results At all in vivo imaging time-points, corneal OCT revealed an increase in backscatter of light and confocal imaging revealed an acellular zone at the graft-host interface. At all post-mortem time-points, immunohistochemistry revealed a complete absence of α-SMA staining at the graft-host interface. At 4 hours, extracellular fibronectin staining was identified along the graft-host interface and both fibronectin and TUNEL assay were positive within adjacent cells extending into the host stroma. By day 2, fibronectin and TUNEL staining diminished and a distinct acellular zone was present in the region of previously TUNEL-positive cells. Conclusions OCT imaging consistently showed increased reflectivity at the graft-host interface in cat corneas in the days post-DSAEK. This was not associated with myofibroblast differentiation at the graft-host interface, but rather with apoptosis and the development of a subsequent acellular zone. The roles of extracellular matrix changes and keratocyte cell death and repopulation should be investigated further as potential contributors to the interface optical changes. PMID:24098706

  8. Grafting as a method for studying development in the filamentous fungus Podospora anserina.

    PubMed

    Silar, Philippe

    2011-08-01

    While grafting and transplant experiments have extensively been used to study development in animals and plants, they have seldom been employed to study fungal development. Here, grafting is used to study the interplay between mycelium and multicellular fruiting bodies during maturation in the model ascomycete Podospora anserina. Data indicate that grafts need a competent mycelium to continue their ripening. Vegetative incompatibility does not prevent transplanted fructifications to undergo development. Grafting onto mutant mycelia confirmed a previous model stating that the NADPH oxidase PaNox1 is required in the developing fruiting bodies, while the MAP kinase cascade PaMpk1 is required in the mycelium. Data also show that the IDC1 protein is required not only in the developing fruiting bodies but also in the mycelium, likely because of its role in anastomosis. Finally, entry inside the grafted fruiting bodies of a ribosomal protein tagged with GFP could be detected, suggesting that cellular components are imported from the underlying mycelium during maturation. Copyright © 2011 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  9. One Year Outcomes of 101 BeGraft Stent Grafts used as Bridging Stents in Fenestrated Endovascular Repairs.

    PubMed

    Spear, Rafaelle; Sobocinski, Jonathan; Hertault, Adrien; Delloye, Matthieu; Azzauiu, Richard; Fabre, Dominique; Haulon, Stéphan

    2018-04-01

    To evaluate the outcomes of the second generation BeGraft balloon expandable covered stent Graft System (Bentley InnoMed, Hechingen, Germany) implanted as bridging stent grafts during fenestrated endovascular aortic repair (FEVAR) of complex aneurysms. This was a single centre prospective study including all consecutive patients treated by FEVAR performed with second generation BeGraft stent grafts as bridging stents. Demographics of patients, diameter and length of the bridging stent grafts, technical success, re-interventions, occlusions, post-operative events, and imaging (Cone Beam CT and/or CT scan, and contrast enhanced ultrasound) were prospectively collected in an electronic database. Duplex ultrasound was performed before discharge and at 6 month follow-up. At 1 year, patients were evaluated clinically and by imaging (CT and ultrasound). Between November 2015 and September 2016, 39 consecutive patients (one woman) were treated with custom made fenestrated endografts (2-5 fenestrations) for complex aneurysms or type 1 endoleak after EVAR, using a variety of bridging stents including the BeGraft. All 101 BeGraft stent grafts were successfully delivered and deployed. There was no in hospital mortality. Early fenestration patency rate was 99% (96/97); the sole target vessel post-operative occlusion was secondary to a dissection of the renal artery distal to the stent. Complementary stenting was unsuccessful in recovering renal artery patency; bilateral renal stent occlusion was observed in the same patient on a CT scan performed 2 months after the procedure. He required post-operative dialysis. No additional renal impairment was observed. During follow-up (median 13 months [11-15]), all fenestrations stented with BeGraft stent grafts remained patent (95/97, 98%). One type 1b endoleak was detected and treated (2.6%). BeGraft stent grafts used as bridging stents during FEVAR are associated with favourable outcomes at 1 year follow-up. Long-term follow-up is

  10. Single-Center Experience Using Marginal Liver Grafts in Korea.

    PubMed

    Park, P-J; Yu, Y-D; Yoon, Y-I; Kim, S-R; Kim, D-S

    2018-05-01

    Liver transplantation (LT) is an established therapeutic modality for patients with end-stage liver disease. The use of marginal donors has become more common worldwide due to the sharp increase in recipients, with a consequent shortage of suitable organs. We analyzed our single-center experience over the last 8 years in LT to evaluate the outcomes of using so-called "marginal donors." We retrospectively analyzed the database of all LTs performed at our institution from 2009 to 2017. Only patients undergoing deceased-donor LTs were analyzed. Marginal grafts were defined as livers from donors >60 years of age, livers from donors with serum sodium levels >155 mEq, graft steatosis >30%, livers with cold ischemia time ≥12 hours, livers from donors who were hepatitis B or C virus positive, livers recovered from donation after cardiac death, and livers split between 2 recipients. Patients receiving marginal grafts (marginal group) were compared with patients receiving standard grafts (standard group). A total of 106 patients underwent deceased-donor LT. There were 55 patients in the standard group and 51 patients in the marginal group. There were no significant differences in terms of age, sex, Model for End-Stage Liver Disease score, underlying liver disease, presence of hepatocellular carcinoma, and hospital stay between the 2 groups. Although the incidence of acute cellular rejection, cytomegalovirus infection, and postoperative complications was similar between the 2 groups, the incidence of early allograft dysfunction was higher in the marginal group. With a median follow-up of 26 months, the 1-, 3-, and 5-year overall and graft (death-censored) survivals in the marginal group were 85.5%, 75%, and 69.2% and 85.9%, 83.6%, and 77.2%, respectively. Patient overall survival and graft survival (death-censored) were significantly lower in the marginal group (P = .023 and P = .048, respectively). On multivariate analysis, receiving a marginal graft (hazard ratio [HR

  11. Upcycling of polypropylene waste by surface modification using radiation-induced grafting

    NASA Astrophysics Data System (ADS)

    Hassan, Muhammad Inaam ul; Taimur, Shaista; Yasin, Tariq

    2017-11-01

    In this work, upcycling of polypropylene waste into amidoxime functionalized polypropylene adsorbent was studied using radiation-induced grafting technique. Polypropylene waste (PPw) was resulted from accelerated thermal ageing of polypropylene (PP). Bulk grafting of acrylonitrile (AN) onto PPw was achieved by simultaneous radiation grafting method using gamma rays. Degree of grafting of AN on PPw is affected by absorbed dose and dose rate. The acrylonitrile groups of grafted PPw were chemically converted into amidoxime functionality. Both the acrylonitrile-grafted PP waste and its amidoxime product were investigated by FTIR, XRD, SEM-EDX and TGA techniques. The prepared amidoxime adsorbent with amidoxime group density of 8.06 mmol/g was used for removal of copper ions from aqueous solutions. The effects of various physicochemical conditions such as: solution pH, adsorbent content, initial metal ion concentration and time on adsorption were studied to maximize adsorption of metal ion. Pseudo-first-order, pseudo-second-order and intra-particle diffusion models were applied to study the kinetics of adsorption. Maximum Langmuir adsorption capacity of 208.3 mg/g at pH 5.0 with optimum contact time of 120 min was observed. Utilization of PP waste and its comparable adsorption capacity with existing radiation grafted polymer-based adsorbents provide a new, cheap and cost effective system.

  12. Graft-versus-host disease

    MedlinePlus

    GVHD; Bone marrow transplant - graft-versus-host disease; Stem cell transplant - graft-versus-host disease; Allogeneic transplant - ... GVHD may occur after a bone marrow, or stem cell, transplant in which someone receives bone marrow ...

  13. Morphologic and Histologic Comparison of Hypertrophic Scar in Nude Mice, T-Cell Receptor, and Recombination Activating Gene Knockout Mice.

    PubMed

    Momtazi, Moein; Ding, Jie; Kwan, Peter; Anderson, Colin C; Honardoust, Dariush; Goekjian, Serge; Tredget, Edward E

    2015-12-01

    Proliferative scars in nude mice have demonstrated morphologic and histologic similarities to human hypertrophic scar. Gene knockout technology provides the opportunity to study the effect of deleting immune cells in various disease processes. The authors' objective was to test whether grafting human skin onto T-cell receptor (TCR) αβ-/-γδ-/-, recombination activating gene (RAG)-1-/-, and RAG-2γ-/-c-/- mice results in proliferative scars consistent with human hypertrophic scar and to characterize the morphologic, histologic, and cellular changes that occur after removing immune cells. Nude TCRαβ-/-γδ-/-, RAG-1-/-, and RAG-2-/-γc-/- mice (n = 20 per strain) were grafted with human skin and euthanized at 30, 60, 120, and 180 days. Controls (n = 5 per strain) were autografted with mouse skin. Scars and normal skin were harvested at each time point. Sections were stained with hematoxylin and eosin, Masson's trichrome, and immunohistochemistry for anti-human leukocyte antigen-ABC, α-smooth muscle actin, decorin, and biglycan. TCRαβ-/-γδ-/-, RAG-1-/-, and RAG-2-/-γc-/- mice grafted with human skin developed firm, elevated scars with histologic and immunohistochemical similarities to human hypertrophic scar. Autografted controls showed no evidence of pathologic scarring. Knockout animals demonstrated a capacity for scar remodeling not observed in nude mice where reductions in α-smooth muscle actin staining pattern and scar thickness occurred over time. Human skin transplanted onto TCRαβ-/-γδ-/-, RAG-1-/-, and RAG-2-/-γc-/- mice results in proliferative scars with morphologic and histologic features of human hypertrophic scar. Remodeling of proliferative scars generated in knockout animals is analogous to changes in human hypertrophic scar. These animal models may better represent the natural history of human hypertrophic scar.

  14. Early excision and grafting, an alternative approach to the surgical management of large body surface area levamisole-adulterated cocaine induced skin necrosis.

    PubMed

    Miner, Jason; Gruber, Paul; Perry, Travis L

    2015-05-01

    Levamisole-adulterated cocaine as a cause of retiform purpura progressing to full-thickness skin necrosis was first documented in 2003 and currently comprises over 200 reported cases. Whereas, its presentation, pathophysiology, and diagnostic workup have been reasonably well-defined, only one publication has significantly detailed its surgical management. For this reason there exists a relative absence of data in comparison to its reported incidence to suggest a preferred treatment strategy. In the case mentioned, treatment emphasized delayed surgical intervention while awaiting lesion demarcation and the monitoring of autoantibodies. At our institution we offer an alternative approach and present the case of a 34 year old female who presented with 49% TBSA, levamisole-induced skin necrosis managed with early surgical excision and skin grafting. The patient presented three days following cocaine exposure with painful, purpura involving the ears, nose, buttocks, and bilateral lower extremities which quickly progressed to areas of full-thickness necrosis. Lab analysis demonstrated elevated p-ANCA and c-ANCA, as well as leukopenia, decreased C4 complement, and urinalysis positive for levamisole, corroborating the diagnosis. Contrasting the most thoroughly documented case in which the patient underwent first surgical excision on hospital day 36 and underwent 18 total excisions, our patient underwent first excision on hospital day 10 and received only one primary excision prior to definitive autografting. To our knowledge, this is the largest surface area surgically treated that did not result in surgical amputation or autoamputation of limbs or appendages, respectively. We contend that early excision and grafting provides optimal surgical management of this syndrome while avoiding the morbidity seen with delayed intervention. Published by Elsevier Ltd.

  15. Posterior repair with perforated porcine dermal graft.

    PubMed

    Taylor, G Bernard; Moore, Robert D; Miklos, John R; Mattox, T Fleming

    2008-01-01

    To compare postoperative vaginal incision separation and healing in patients undergoing posterior repair with perforated porcine dermal grafts with those that received grafts without perforations. Secondarily, the tensile properties of the perforated and non-perforated grafts were measured and compared. This was a non-randomized retrospective cohort analysis of women with stage II or greater rectoceles who underwent posterior repair with perforated and non-perforated porcine dermal grafts (Pelvicol(TM) CR Bard Covington, GA USA). The incidence of postoperative vaginal incision separation (dehiscence) was compared. A secondary analysis to assess graft tensile strength, suture pull out strength, and flexibility after perforation was performed using standard test method TM 0133 and ASTM bending and resistance protocols. Seventeen percent of patients (21/127) who received grafts without perforations developed vaginal incision dehiscence compared to 7% (5/71) of patients who received perforated grafts (p = 0.078). Four patients with vaginal incision dehiscence with non-perforated grafts required surgical revision to facilitate healing. Neither tensile strength or suture pull out strength were significantly different between perforated and non-perforated grafts (p = 0.81, p = 0.29, respectively). There was no difference in the flexibility of the two grafts (p = 0.20). Perforated porcine dermal grafts retain their tensile properties and are associated with fewer vaginal incision dehiscences.

  16. Emerging concepts in liver graft preservation

    PubMed Central

    Bejaoui, Mohamed; Pantazi, Eirini; Folch-Puy, Emma; Baptista, Pedro M; García-Gil, Agustín; Adam, René; Roselló-Catafau, Joan

    2015-01-01

    The urgent need to expand the donor pool in order to attend to the growing demand for liver transplantation has obliged physicians to consider the use of suboptimal liver grafts and also to redefine the preservation strategies. This review examines the different methods of liver graft preservation, focusing on the latest advances in both static cold storage and machine perfusion (MP). The new strategies for static cold storage are mainly designed to increase the fatty liver graft preservation via the supplementation of commercial organ preservation solutions with additives. In this paper we stress the importance of carrying out effective graft washout after static cold preservation, and present a detailed discussion of the future perspectives for dynamic graft preservation using MP at different temperatures (hypothermia at 4 °C, normothermia at 37 °C and subnormothermia at 20 °C-25 °C). Finally, we highlight some emerging applications of regenerative medicine in liver graft preservation. In conclusion, this review discusses the “state of the art” and future perspectives in static and dynamic liver graft preservation in order to improve graft viability. PMID:25593455

  17. Influence of Diabetes on Long-Term Coronary Artery Bypass Graft Patency.

    PubMed

    Raza, Sajjad; Blackstone, Eugene H; Houghtaling, Penny L; Rajeswaran, Jeevanantham; Riaz, Haris; Bakaeen, Faisal G; Lincoff, A Michael; Sabik, Joseph F

    2017-08-01

    Nearly 50% of patients undergoing coronary artery bypass grafting have diabetes. However, little is known about the influence of diabetes on long-term patency of bypass grafts. Because patients with diabetes have more severe coronary artery stenosis, we hypothesized that graft patency is worse in patients with than without diabetes. This study sought to examine the influence of diabetes on long-term patency of bypass grafts. From 1972 to 2011, 57,961 patients underwent primary isolated coronary artery bypass grafting. Of these, 1,372 pharmacologically treated patients with diabetes and 10,147 patients without diabetes had 15,887 postoperative angiograms; stenosis was quantified for 7,903 internal thoracic artery (ITA) grafts and 20,066 saphenous vein grafts. Status of graft patency across time was analyzed by longitudinal nonlinear mixed-effects modeling. ITA graft patency was stable over time and similar in patients with and without diabetes: at 1, 5, 10, and 20 years, 97%, 97%, 96%, and 96% in patients with diabetes, and 96%, 96%, 95%, and 93% in patients without diabetes, respectively (early p = 0.20; late p = 0.30). In contrast, saphenous vein graft patency declined over time and similarly in patients with and without diabetes: at 1, 5, 10, and 20 years, 78%, 70%, 57%, and 42% in patients with diabetes, and 82%, 72%, 58%, and 41% in patients without diabetes, respectively (early p < 0.002; late p = 0.60). After adjusting for patient characteristics, diabetes was associated with higher early patency of ITA grafts (odds ratio: 0.63; 95% confidence limits: 0.43 to 0.91; p = 0.013), but late patency of ITA grafts was similar in patients with and without diabetes (p = 0.80). Early and late patency of saphenous vein grafts were similar in patients with and without diabetes (early p = 0.90; late p = 0.80). Contrary to our hypothesis, diabetes did not influence long-term patency of bypass grafts. Use of ITA grafts should be maximized in patients

  18. Role of Polymer-grafted Nanoparticle Interactions in Supercrystal Self-Assembly

    NASA Astrophysics Data System (ADS)

    Horst, Nathan; Waltmann, Curt; Travesset, Alex

    Many successful strategies are available for the programmable self-assembly of nanoparticle superlattices. In this talk, we discuss the the case of nanoparticles with grafted polymer ligands. For very short polymers, the phase diagram is rationalized by borrowing results from hard-sphere packing models. Although a clear correlation exists between the maximum of the packing fraction of hard spheres and supercrystal equilibrium phases found experimentally, these systems are flexible, which leads to clear deviations from the sphere packing model. Using theoretical and computational models, we present an investigation of the interactions of polymer-grafted nanoparticles, focusing on the role of the rigidity of the chain, and how it affects the resulting two and three-dimensional superlattice structures. Comparison with an experimental system of gold nanoparticles grafted with polyethylene glycol is also presented. Supported by the U.S. Department of Energy (U.S. DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering. Ames Laboratory is operated for the U.S. DOE by Iowa State University under Contract No. DE-AC02-07CH11358.

  19. A grafting from approach to graft polystyrene chains at the surface of graphene nanolayers by RAFT polymerization: Various graft densities from hydroxyl groups

    NASA Astrophysics Data System (ADS)

    Roghani-Mamaqani, Hossein; Khezri, Khezrollah

    2016-01-01

    (3-Aminopropyl) triethoxysilane was grafted at the surface of GO in low and high different graft densities to yield GOHAL and GOHAH, respectively. Subsequently, 2-(dodecylthiocarbonothioylthio)-2-methylpropionic acid (RA) was attached at the surface of GOHAL and GOHAH by an amidation reaction to yield GOHRL and GOHRH, respectively. Then, GOHRL and GOHRH were used in grafting from RAFT polymerization of styrene. Grafting of APTES and RA was approved by Fourier transform infrared spectroscopy, X-ray photo electron spectroscopy, and Raman spectroscopy. Expansion of graphene interlayer by oxidation and functionalization processes was evaluated by X-ray diffraction. Conversion values of styrene were calculated using gas chromatography. Molecular weight and PDI values of attached polystyrene (PS) chains were studied by size exclusion chromatography. Thermogravimetric analysis was also used to investigate the degradation temperatures, char contents, and graft contents of modifiers and PS chains. GOHRH and GOHRL reach to char content of 55.3 and 45.2% at 600 °C, which shows that weight ratio of modifier (APTES and RA moieties) is 15.3 and 5.2%, respectively. Scanning and transmission electron microscopies show that graphite layers with flat and smooth surface wrinkled after oxidation and turned to opaque layers by grafting PS.

  20. Comparison of transforaminal lumbar interbody fusion outcomes in patients receiving rhBMP-2 versus autograft.

    PubMed

    Khan, Taleef R; Pearce, Kalin R; McAnany, Steven J; Peters, Colleen M; Gupta, Munish C; Zebala, Lukas P

    2018-03-01

    Recombinant human bone morphogenetic protein 2 (rhBMP-2) plays a pivotal role in complex spine surgery. Despite its limited approval, the off-label use of rhBMP-2 is prevalent, particularly in transforaminal lumbar interbody fusions (TLIFs). To determine the effectiveness and safety of rhBMP-2 use in TLIF procedures versus autograft. Retrospective cohort study. Patients older than 18 years undergoing spine surgery for lumbar degenerative spine disease at a single academic institution. Clinical outcome was determined according to patient records. Radiographic outcome was determined according to plain X-rays and computed tomography (CT). A retrospective study from 1997 to 2014 was conducted on 191 adults undergoing anterior-posterior instrumented spinal fusion with TLIF at a single academic institution. Patient data were gathered from operative notes, follow-up clinic notes, and imaging studies to determine complications and fusion rates. One hundred eighty-seven patients fit the criteria, which included patients with a minimum of one TLIF, and had a minimum 2-year radiographic and clinical follow-up. Patients were further classified into a BMP group (n=83) or non-BMP group (n=104). Three logistic regression models were run using rhBMP-2 exposure as the independent variable. The respective outcome variables were TLIF-related complications (radiculitis, seroma, osteolysis, and ectopic bone), surgical complications, and all complications. Bone morphogenetic protein (n=83) and non-BMP (n=104) groups had similar baseline demographics (sex, diabetes, pre-existing cancer). On average, the BMP and non-BMP groups were similarly aged (51.9 vs. 47.9 years, p>.05), but the BMP group had a shorter follow-up time (3.03 vs. 4.06 years; p<.001) and fewer smokers (8 vs. 21 patients; p<.048). The fusion rate for the BMP and non-BMP groups was 92.7% and 92.3%, respectively. The pseudoarthrosis rate was 7.5% (14 of 187 patients). Radiculitis was observed in seven patients in the BMP