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Sample records for acellular nerve grafts

  1. Chemically extracted acellular allogeneic nerve graft combined with ciliary neurotrophic factor promotes sciatic nerve repair

    PubMed Central

    Zhang, Yanru; Zhang, Hui; Katiella, Kaka; Huang, Wenhua

    2014-01-01

    A chemically extracted acellular allogeneic nerve graft can reduce postoperative immune rejection, similar to an autologous nerve graft, and can guide neural regeneration. However, it remains poorly understood whether a chemically extracted acellular allogeneic nerve graft combined with neurotrophic factors provides a good local environment for neural regeneration. This study investigated the repair of injured rat sciatic nerve using a chemically extracted acellular allogeneic nerve graft combined with ciliary neurotrophic factor. An autologous nerve anastomosis group and a chemical acellular allogeneic nerve bridging group were prepared as controls. At 8 weeks after repair, sciatic functional index, evoked potential amplitude of the soleus muscle, triceps wet weight recovery rate, total number of myelinated nerve fibers and myelin sheath thickness were measured. For these indices, values in the three groups showed the autologous nerve anastomosis group > chemically extracted acellular nerve graft + ciliary neurotrophic factor group > chemical acellular allogeneic nerve bridging group. These results suggest that chemically extracted acellular nerve grafts combined with ciliary neurotrophic factor can repair sciatic nerve defects, and that this repair is inferior to autologous nerve anastomosis, but superior to chemically extracted acellular allogeneic nerve bridging alone. PMID:25221592

  2. Chemically extracted acellular allogeneic nerve graft combined with ciliary neurotrophic factor promotes sciatic nerve repair.

    PubMed

    Zhang, Yanru; Zhang, Hui; Katiella, Kaka; Huang, Wenhua

    2014-07-15

    A chemically extracted acellular allogeneic nerve graft can reduce postoperative immune rejection, similar to an autologous nerve graft, and can guide neural regeneration. However, it remains poorly understood whether a chemically extracted acellular allogeneic nerve graft combined with neurotrophic factors provides a good local environment for neural regeneration. This study investigated the repair of injured rat sciatic nerve using a chemically extracted acellular allogeneic nerve graft combined with ciliary neurotrophic factor. An autologous nerve anastomosis group and a chemical acellular allogeneic nerve bridging group were prepared as controls. At 8 weeks after repair, sciatic functional index, evoked potential amplitude of the soleus muscle, triceps wet weight recovery rate, total number of myelinated nerve fibers and myelin sheath thickness were measured. For these indices, values in the three groups showed the autologous nerve anastomosis group > chemically extracted acellular nerve graft + ciliary neurotrophic factor group > chemical acellular allogeneic nerve bridging group. These results suggest that chemically extracted acellular nerve grafts combined with ciliary neurotrophic factor can repair sciatic nerve defects, and that this repair is inferior to autologous nerve anastomosis, but superior to chemically extracted acellular allogeneic nerve bridging alone. PMID:25221592

  3. Schwann-like cells seeded in acellular nerve grafts improve nerve regeneration

    PubMed Central

    2014-01-01

    Background This study evaluated whether Schwann-like cells (SLCs) induced from bone marrow-derived mesenchymal stem cells (BM-MSCs) transplanted into acellular nerve grafts (ANGs) could repair nerve defects compared with nerve isografts and ANGs with BM-MSCs. Methods BM-MSCs extracted, separated and purified from the bone marrow of rats, and some of the BM-MSCs were cultured with mixed induction agents that could induce BM-MSCs into SLCs. Either SLCs or BM-MSCs were seeded onto 10-mm ANGs, and the isografts were chosen as the control. The walking-track test, tibialis anterior muscle weight measurement, electrophysiological examination, toluidine blue staining, transmission electron micrographs and immunostaining of S-100 and VEGF in these three groups were evaluated in a 10-mm rat sciatic injury-repair model. Results The walking-track test, tibialis anterior muscle weight measurement and electrophysiological examination of the sciatic nerve suggested the groups of ANGs with SLCs and isografts obtained better results than the BM-MSC group (P < 0.05). Meanwhile, the results of the SLCs and isograft groups were similar (P > 0.05). All the histomorphometric analyses (toluidine blue staining, transmission electron micrographs and immunostaining of S-100 and VEGF) showed that there were more regenerating nerve fibers in the group of ANGs with SLCs than the BM-MSCs (P < 0.05), but there was no significant difference between the SLC and isograft groups (P > 0.05). Conclusions SLCs seeded in ANGs and isografts show better functional regeneration compared with BM-MSCs seeded in ANGs. Additionally, SLCs combined with ANGs present almost the same outcome as the isografts. Therefore, SLCs with ANGs can be a good choice in nerve defect repairs. PMID:24885337

  4. Cartilage oligomeric matrix protein enhances the vascularization of acellular nerves

    PubMed Central

    Cui, Wei-ling; Qiu, Long-hai; Lian, Jia-yan; Li, Jia-chun; Hu, Jun; Liu, Xiao-lin

    2016-01-01

    Vascularization of acellular nerves has been shown to contribute to nerve bridging. In this study, we used a 10-mm sciatic nerve defect model in rats to determine whether cartilage oligomeric matrix protein enhances the vascularization of injured acellular nerves. The rat nerve defects were treated with acellular nerve grafting (control group) alone or acellular nerve grafting combined with intraperitoneal injection of cartilage oligomeric matrix protein (experimental group). As shown through two-dimensional imaging, the vessels began to invade into the acellular nerve graft from both anastomotic ends at day 7 post-operation, and gradually covered the entire graft at day 21. The vascular density, vascular area, and the velocity of revascularization in the experimental group were all higher than those in the control group. These results indicate that cartilage oligomeric matrix protein enhances the vascularization of acellular nerves. PMID:27127495

  5. A comparative study of acellular nerve xenografts and allografts in repairing rat facial nerve defects.

    PubMed

    Huang, Haitao; Xiao, Hongxi; Liu, Huawei; Niu, Yu; Yan, Rongzeng; Hu, Min

    2015-10-01

    Acellular nerves are composed of a basal lamina tube, which retains sufficient bioactivity to promote axon regeneration, thereby repairing peripheral nerve gaps. However, the clinical application of acellular allografts has been restricted due to its limited availability. To investigate whether xenografts, a substitute to allograft acellular nerves in abundant supply, could efficiently promote nerve regeneration, rabbit and rat acellular nerve grafts were used to reconstruct 1 cm defects in Wistar rat facial nerves. Autologous peroneal nerve grafts served as a positive control group. A total of 12 weeks following the surgical procedure, the axon number, myelinated axon number, myelin sheath thickness, and nerve conduction velocity of the rabbit and rat‑derived acellular nerve grafts were similar, whereas the fiber diameter of the rabbit‑derived acellular xenografts decreased, as compared with those of rat‑derived acellular allografts. Autografts exerted superior effects on nerve regeneration; however, no significant difference was observed between the axon number in the autograft group, as compared with the two acellular groups. These results suggested that autografts perform better than acellular nerve grafts, and chemically extracted acellular allografts and xenografts have similar effects on the regeneration of short facial nerve defects. PMID:26239906

  6. Improved Peripheral Nerve Regeneration Using Acellular Nerve Allografts Loaded with Platelet-Rich Plasma

    PubMed Central

    Zheng, Canbin; Huang, Xijun; He, Caifeng; Jiang, Li; Quan, Daping

    2014-01-01

    Acellular nerve allografts (ANAs) behave in a similar manner to autografts in supporting axonal regeneration in the repair of short peripheral nerve defects but fail in larger defects. The objective of this article is to evaluate the effect of ANA supplemented with platelet-rich plasma (PRP) to improve nerve regeneration after surgical repair and to discuss the mechanisms that underlie this approach. Autologous PRP was obtained from rats by double-step centrifugation and was characterized by determining platelet numbers and the release of growth factors. Forty-eight Sprague–Dawley rats were randomly divided into 4 groups (12/group), identified as autograft, ANA, ANA loaded with PRP (ANA+PRP), and ANA loaded with platelet-poor plasma (PPP, ANA+PPP). All grafts were implanted to bridge long-gap (15 mm) sciatic nerve defects. We found that PRP with a high platelet concentration exhibited a sustained release of growth factors. Twelve weeks after surgery, the autograft group displayed the highest level of reinnervation, followed by the ANA+PRP group. The ANA+PRP group showed a better electrophysiology response for amplitude and conduction velocity than the ANA and ANA+PPP groups. Based on histological evaluation, the ANA+PRP and autograft groups had higher numbers of regenerating nerve fibers. Quantitative real-time polymerase chain reaction (qRT-PCR) demonstrated that PRP boosted expression of neurotrophins in the regenerated nerves. Moreover, the ANA+PRP and autograft groups showed excellent physiological outcomes in terms of the prevention of muscle atrophy. In conclusion, ANAs loaded with PRP as tissue-engineered scaffolds can enhance nerve regeneration and functional recovery after the repair of large nerve gaps nearly as well as autografts. PMID:24901030

  7. Three-dimensional Reconstruction of the Microstructure of Human Acellular Nerve Allograft.

    PubMed

    Zhu, Shuang; Zhu, Qingtang; Liu, Xiaolin; Yang, Weihong; Jian, Yutao; Zhou, Xiang; He, Bo; Gu, Liqiang; Yan, Liwei; Lin, Tao; Xiang, Jianping; Qi, Jian

    2016-01-01

    The exact inner 3D microstructure of the human peripheral nerve has been a mystery for decades. Therefore, it has been difficult to solve several problems regarding peripheral nerve injury and repair. We used high-resolution X-ray computed microtomography (microCT) to scan a freeze-dried human acellular nerve allograft (hANA). The microCT images were then used to reconstruct a 3D digital model, which was used to print a 3D resin model of the nerve graft. The 3D digital model of the hANA allowed visualization of all planes. The magnified 3D resin model clearly showed the nerve bundles and basement membrane tubes of the hANA. Scanning electron microscopy (SEM) was used to analyse the microstructure of the hANA. Compared to the SEM images, the microCT image clearly demonstrated the microstructure of the hANA cross section at a resolution of up to 1.2 μm. The 3D digital model of the hANA facilitates a clear and easy understanding of peripheral nerve microstructure. Furthermore, the enlarged 3D resin model duplicates the unique inner structure of each individual hANA. This is a crucial step towards achieving 3D printing of a hANA or nerve that can be used as a nerve graft. PMID:27476584

  8. Three-dimensional Reconstruction of the Microstructure of Human Acellular Nerve Allograft

    PubMed Central

    Zhu, Shuang; Zhu, Qingtang; Liu, Xiaolin; Yang, Weihong; Jian, Yutao; Zhou, Xiang; He, Bo; Gu, Liqiang; Yan, Liwei; Lin, Tao; Xiang, Jianping; Qi, Jian

    2016-01-01

    The exact inner 3D microstructure of the human peripheral nerve has been a mystery for decades. Therefore, it has been difficult to solve several problems regarding peripheral nerve injury and repair. We used high-resolution X-ray computed microtomography (microCT) to scan a freeze-dried human acellular nerve allograft (hANA). The microCT images were then used to reconstruct a 3D digital model, which was used to print a 3D resin model of the nerve graft. The 3D digital model of the hANA allowed visualization of all planes. The magnified 3D resin model clearly showed the nerve bundles and basement membrane tubes of the hANA. Scanning electron microscopy (SEM) was used to analyse the microstructure of the hANA. Compared to the SEM images, the microCT image clearly demonstrated the microstructure of the hANA cross section at a resolution of up to 1.2 μm. The 3D digital model of the hANA facilitates a clear and easy understanding of peripheral nerve microstructure. Furthermore, the enlarged 3D resin model duplicates the unique inner structure of each individual hANA. This is a crucial step towards achieving 3D printing of a hANA or nerve that can be used as a nerve graft. PMID:27476584

  9. Ginkgo biloba extract (EGb 761) promotes peripheral nerve regeneration and neovascularization after acellular nerve allografts in a rat model.

    PubMed

    Zhu, Zhaowei; Zhou, Xiang; He, Bo; Dai, Ting; Zheng, Canbin; Yang, Chuang; Zhu, Shuang; Zhu, Jiakai; Zhu, Qingtang; Liu, Xiaolin

    2015-03-01

    This study aimed to investigate whether or not ginkgo biloba extract (EGb 761) enhances peripheral nerve regeneration and vascularization after repair using acellular nerve allografts (ANA). Seventy-two Sprague-Dawley rats were randomly divided into three experimental groups: a unilateral 15-mm sciatic nerve defect was created and repaired with an autologous graft (autograft group); the same defect was repaired with an 18 mm ANA with an i.p. injection of normal saline for 10 days (saline group); and in the final group, the same defect was repaired with an 18 mm ANA with an i.p. injection of EGb 761 for 10 days (EGb 761 group). Axon outgrowth and vascularization were evaluated by immunocytochemistry 14 days post-implantation. The expression of genes associated with angiogenesis was analyzed by real-time polymerase chain reaction (PCR) seven days post-implantation. Compared with the saline group, rats in the EGb 761 group significantly increased the number of myelinated fibers and the average diameter of the nerves within the graft. There is no significant difference between the EGb 761 group and the autograft group. The expression of CD34 and NF200 was significantly higher in the EGb 761 group than in the saline group. Additionally, EGb 761 treatment increased the expression of several angiogenesis-related genes, including Vegf, SOX18, Prom 1, and IL-6. In conclusion, ANA repair with EGb 761 treatment demonstrates effects on peripheral nerve regeneration and vascularization that are equal to those of autologous graft repair, and that are superior to ANA repair alone. PMID:25319407

  10. Study of synergistic role of allogenic skin-derived precursor differentiated Schwann cells and heregulin-1β in nerve regeneration with an acellular nerve allograft.

    PubMed

    Wang, Houlei; Wu, Jingping; Zhang, Xinchao; Ding, Lei; Zeng, Qingmin

    2016-07-01

    Development of tissue structure and three-dimensional microenvironment is crucial for regeneration of axons in the peripheral nerve repair. In this study we aimed to evaluate the efficacy of nerve regeneration by using an acellular nerve allograft (ANA) injected with allogenic skin-derived precursor differentiated Schwann cells (SKP-SCs) and heregulin-1β. Skin-derived precursor cells (SKPs) were generated from dermis of newborn (postnatal day 2) Wistar rats. In a rat model, nerve regeneration was determined across a 15 mm lesion in the sciatic nerve by using an ANA injected with allogenic SKP-SCs and heregulin-1β. The electrophysiological analysis, histological examination and electron microscopy were involved in this study. Cultured SKPs expressed nestin and fibronectin, and differentiated into cells with phenotype of SCs that presented characteristic markers of p75NGFR and S100-β. Implantation of SKP-SCs into the rat models by using ANA and allogenic skin-derived precursor differentiated Schwann cells (SKP-SCs) increases sciatic nerve functional index (SFI), peak amplitudes, nerve conduction velocities, number of myelinated fibers within the graft, while reduces incubation period, sciatic nerve injury-induced weight and contractions loss. Using ANA injected with SKP-SCs combined with heregulin-1β greatly promote peripheral nerve repair in a rat model. Our results suggest that SKP-SCs transplantation with heregulin-1β represents a powerful therapeutic approach, and facilitates the efficacy of acellular nerve allograft in peripheral nerve injury, though the detailed mechanism remains to be elucidated. PMID:27063890

  11. Light-Activated Sealing of Acellular Nerve Allografts following Nerve Gap Injury.

    PubMed

    Fairbairn, Neil G; Ng-Glazier, Joanna; Meppelink, Amanda M; Randolph, Mark A; Valerio, Ian L; Fleming, Mark E; Kochevar, Irene E; Winograd, Jonathan M; Redmond, Robert W

    2016-07-01

    Introduction Photochemical tissue bonding (PTB) uses visible light to create sutureless, watertight bonds between two apposed tissue surfaces stained with photoactive dye. In phase 1 of this two-phase study, nerve gaps repaired with bonded isografts were superior to sutured isografts. When autograft demand exceeds supply, acellular nerve allograft (ANA) is an alternative although outcomes are typically inferior. This study assesses the efficacy of PTB when used with ANA. Methods Overall 20 male Lewis rats had 15-mm left sciatic nerve gaps repaired using ANA. ANAs were secured using epineurial suture (group 1) or PTB (group 2). Outcomes were assessed using sciatic function index (SFI), gastrocnemius muscle mass retention, and nerve histomorphometry. Historical controls from phase 1 were used to compare the performance of ANA with isograft. Statistical analysis was performed using analysis of variance and Bonferroni all-pairs comparison. Results All ANAs had signs of successful regeneration. Mean values for SFI, muscle mass retention, nerve fiber diameter, axon diameter, and myelin thickness were not significantly different between ANA + suture and ANA + PTB. On comparative analysis, ANA + suture performed significantly worse than isograft + suture from phase 1. However, ANA + PTB was statistically comparable to isograft + suture, the current standard of care. Conclusion Previously reported advantages of PTB versus suture appear to be reduced when applied to ANA. The lack of Schwann cells and neurotrophic factors may be responsible. PTB may improve ANA performance to an extent, where they are equivalent to autograft. This may have important clinical implications when injuries preclude the use of autograft. PMID:26878685

  12. Tissue-engineered acellular small diameter long-bypass grafts with neointima-inducing activity.

    PubMed

    Mahara, Atsushi; Somekawa, Shota; Kobayashi, Naoki; Hirano, Yoshiaki; Kimura, Yoshiharu; Fujisato, Toshiya; Yamaoka, Tetsuji

    2015-07-01

    Researchers have attempted to develop efficient antithrombogenic surfaces, and yet small-caliber artificial vascular grafts are still unavailable. Here, we demonstrate the excellent patency of tissue-engineered small-caliber long-bypass grafts measuring 20-30 cm in length and having a 2-mm inner diameter. The inner surface of an acellular ostrich carotid artery was modified with a novel heterobifunctional peptide composed of a collagen-binding region and the integrin α4β1 ligand, REDV. Six grafts were transplanted in the femoral-femoral artery crossover bypass method. Animals were observed for 20 days and received no anticoagulant medication. No thrombogenesis was observed on the luminal surface and five cases were patent. In contrast, all unmodified grafts became occluded, and severe thrombosis was observed. The vascular grafts reported here are the first successful demonstrations of short-term patency at clinically applicable sizes. PMID:25941782

  13. T Lymphocyte Subsets and Cytokines in Rats Transplanted with Adipose-Derived Mesenchymal Stem Cells and Acellular Nerve for Repairing the Nerve Defects

    PubMed Central

    Chen, Ou; Chu, Ting-gang; Ding, Jian; Yu, Qing

    2015-01-01

    Objective The aim of this study was to explore the immunity in rats transplanted with adipose-derived mesenchymal stem cells (ADSCs) and acellular nerve (ACN) for repairing sciatic nerve defects. Methods ADSCs were isolated from the adipose tissues of Wistar rats. Sprague-Dawley rats were used to establish a sciatic nerve defect model and then divided into four groups, according to the following methods : Group A, allogenic nerve graft; Group B, allograft with ACN; Group C, allograft ADSCs+ACN, and Group D, nerve autograft. Results At the day before transplantation and 3, 7, 14, and 28 days after transplantation, orbital venous blood of the Sprague-Dawley rats in each group was collected to detect the proportion of CD3+, CD4+, and CD8+ subsets using flow cytometry and to determine the serum concentration of interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) using enzyme-linked immunosorbent assay (ELISA). At each postoperative time point, the proportion of CD3+, CD4+, and CD8+ subsets and the serum concentration of IL-2, TNF-α, and IFN-γ in group C were all near to those in group B and group D, in which no statistically significant difference was observed. As compared with group A, the proportion of CD3+, CD4+, and CD8+ subsets and the serum concentration of IL-2, TNF-α, and IFN-γ were significantly reduced in group C (p<0.05). Conclusion The artificial nerve established with ADSCs and ACN has no obvious allograft rejection for repairing rat nerve defects. PMID:26361524

  14. Acellular Vascular Grafts Generated from Collagen and Elastin Analogues

    PubMed Central

    Kumar, Vivek A.; Caves, Jeffrey M.; Haller, Carolyn A.; Dai, Erbin; Li, Liying; Grainger, Stephanie; Chaikof, Elliot L.

    2013-01-01

    Tissue engineered vascular grafts require long fabrication times, in part, due to the requirement of cells from a variety of cell sources to produce a robust load bearing, extracellular matrix. Herein, we propose a design strategy for the fabrication of tubular conduits comprised of collagen fiber networks and elastin-like protein polymers to mimic native tissue structure and function. Dense fibrillar collagen networks exhibited an ultimate tensile strength (UTS) of 0.71 ± 0.06 MPa, strain to failure of 37.1 ± 2.2%, and Young’s modulus of 2.09 ± 0.42 MPa, comparing favorably to an UTS and a Young’s modulus for native blood vessels of 1.4 – 11.1 MPa and 1.5 ± 0.3 MPa, respectively. Resilience, a measure of recovered energy during unloading of matrices, demonstrated that 58.9 ± 4.4% of the energy was recovered during loading-unloading cycles. Rapid fabrication of multilayer tubular conduits with maintenance of native collagen ultrastructure was achieved with internal diameters ranging between 1 to 4 mm. Compliance and burst pressures exceeded 2.7 ± 0.3%/100 mmHg and 830 ± 131 mmHg, respectively, with a significant reduction in observed platelet adherence as compared to ePTFE (6.8 ± 0.05 × 105 vs. 62 ± 0.05 × 105 platelets/mm2, p < 0.01). Using a rat aortic interposition model, early in vivo responses were evaluated at 2 weeks via Doppler ultrasound and CT angiography with immunohistochemistry confirming a limited early inflammatory response (n=8). Engineered collagen-elastin composites represent a promising strategy for fabricating synthetic tissues with defined extracellular matrix content, composition, and architecture. PMID:23743129

  15. A preliminary study on the effects of acellular tissue graft augmentation in acute Achilles tendon ruptures.

    PubMed

    Lee, Daniel K

    2008-01-01

    Acute Achilles tendon rupture injuries present surgical challenges because of the mechanical forces placed on this tendon. The purpose of this study was to evaluate the effectiveness of an acellular human dermal tissue matrix, GraftJacket Matrix (Wright Medical Technology, Inc., Arlington, TN), as an augmentation material in acute Achilles tendon repair. Eleven consecutive patients with acute tendon ruptures were evaluated and followed up (20-31 months). Primary repair was followed by augmentation with the graft sutured circumferentially around the tendon. Patients were placed in an early functional rehabilitation program with postoperative evaluation at 3, 6, and 12 months. Outcome scores were calculated based on the American Orthopaedic Foot and Ankle Society ankle-hindfoot scoring system. At 20-month postoperative follow-up, there have been no cases of rerupture or recurrent pain. The average return-to-activity time was 11.8 +/- 0.75 weeks. These retrospective clinical results suggest that with an acellular human dermal tissue matrix to augment acute Achilles tendon, primary repair offers a desirable return-to-activity time without any rerupture or complications. ACFAS Level of Clinical Evidence: 2c. PMID:18156058

  16. Repair of lacerated anterior tibial tendon with acellular tissue graft augmentation.

    PubMed

    DiDomenico, Lawrence A; Blasko, Gregory A; Cane, Laurence; Cross, Davina J

    2012-01-01

    In the present case report, we describe the surgical repair of a complete laceration of the anterior tibial tendon using acellular human dermal tissue matrix. A 17-year-old, elite league hockey player was injured in the locker room when a teammate still clad in ice skates stepped on his bare left foot. After evaluation at a local emergency department, the patient presented to our office the next day for additional evaluation. It was determined that surgery would be performed using acellular tissue graft augmentation, followed by physical therapy. Within 7 weeks of the injury, the athlete returned to his original level of activity. At 3 years of follow-up, he was playing Division 1 hockey at the university level. We believe that augmentation of the tendon repair with the grafting material enhanced the tendon tensile strength and promoted ingrowth through vascular channels. This, combined with the patient's dedication to physical therapy, led to excellent recovery in less time than anticipated. PMID:22762944

  17. Ulnar Nerve Injury after Flexor Tendon Grafting.

    PubMed

    McCleave, Michael John

    2016-10-01

    A 43-year-old female is presented who underwent a two-stage tendon reconstruction and developed a low ulnar nerve palsy postoperatively. Exploration found that the tendon graft was passing through Guyon's canal and that the ulnar nerve was divided. This is a previously unreported complication. The reconstruction is discussed, the literature reviewed and a guide is given on how to identify the correct tissue plane when passing a tendon rod. PMID:27595967

  18. Immunohistochemical, Ultrastructural and Functional Analysis of Axonal Regeneration through Peripheral Nerve Grafts Containing Schwann Cells Expressing BDNF, CNTF or NT3

    PubMed Central

    Godinho, Maria João; Teh, Lip; Pollett, Margaret A.; Goodman, Douglas; Hodgetts, Stuart I.; Sweetman, Iain; Walters, Mark; Verhaagen, Joost; Plant, Giles W.; Harvey, Alan R.

    2013-01-01

    We used morphological, immunohistochemical and functional assessments to determine the impact of genetically-modified peripheral nerve (PN) grafts on axonal regeneration after injury. Grafts were assembled from acellular nerve sheaths repopulated ex vivo with Schwann cells (SCs) modified to express brain-derived neurotrophic factor (BDNF), a secretable form of ciliary neurotrophic factor (CNTF), or neurotrophin-3 (NT3). Grafts were used to repair unilateral 1 cm defects in rat peroneal nerves and 10 weeks later outcomes were compared to normal nerves and various controls: autografts, acellular grafts and grafts with unmodified SCs. The number of regenerated βIII-Tubulin positive axons was similar in all grafts with the exception of CNTF, which contained the fewest immunostained axons. There were significantly lower fiber counts in acellular, untransduced SC and NT3 groups using a PanNF antibody, suggesting a paucity of large caliber axons. In addition, NT3 grafts contained the greatest number of sensory fibres, identified with either IB4 or CGRP markers. Examination of semi- and ultra-thin sections revealed heterogeneous graft morphologies, particularly in BDNF and NT3 grafts in which the fascicular organization was pronounced. Unmyelinated axons were loosely organized in numerous Remak bundles in NT3 grafts, while the BDNF graft group displayed the lowest ratio of umyelinated to myelinated axons. Gait analysis revealed that stance width was increased in rats with CNTF and NT3 grafts, and step length involving the injured left hindlimb was significantly greater in NT3 grafted rats, suggesting enhanced sensory sensitivity in these animals. In summary, the selective expression of BDNF, CNTF or NT3 by genetically modified SCs had differential effects on PN graft morphology, the number and type of regenerating axons, myelination, and locomotor function. PMID:23950907

  19. Repair of peripheral nerve defects with chemically extracted acellular nerve allografts loaded with neurotrophic factors-transfected bone marrow mesenchymal stem cells.

    PubMed

    Zhang, Yan-Ru; Ka, Ka; Zhang, Ge-Chen; Zhang, Hui; Shang, Yan; Zhao, Guo-Qiang; Huang, Wen-Hua

    2015-09-01

    Chemically extracted acellular nerve allografts loaded with brain-derived neurotrophic factor-transfected or ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells have been shown to repair sciatic nerve injury better than chemically extracted acellular nerve allografts alone, or chemically extracted acellular nerve allografts loaded with bone marrow mesenchymal stem cells. We hypothesized that these allografts compounded with both brain-derived neurotrophic factor- and ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells may demonstrate even better effects in the repair of peripheral nerve injury. We cultured bone marrow mesenchymal stem cells expressing brain-derived neurotrophic factor and/or ciliary neurotrophic factor and used them to treat sciatic nerve injury in rats. We observed an increase in sciatic functional index, triceps wet weight recovery rate, myelin thickness, number of myelinated nerve fibers, amplitude of motor-evoked potentials and nerve conduction velocity, and a shortened latency of motor-evoked potentials when allografts loaded with both neurotrophic factors were used, compared with allografts loaded with just one factor. Thus, the combination of both brain-derived neurotrophic factor and ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells can greatly improve nerve injury. PMID:26604913

  20. Repair of peripheral nerve defects with chemically extracted acellular nerve allografts loaded with neurotrophic factors-transfected bone marrow mesenchymal stem cells

    PubMed Central

    Zhang, Yan-ru; Ka, Ka; Zhang, Ge-chen; Zhang, Hui; Shang, Yan; Zhao, Guo-qiang; Huang, Wen-hua

    2015-01-01

    Chemically extracted acellular nerve allografts loaded with brain-derived neurotrophic factor-transfected or ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells have been shown to repair sciatic nerve injury better than chemically extracted acellular nerve allografts alone, or chemically extracted acellular nerve allografts loaded with bone marrow mesenchymal stem cells. We hypothesized that these allografts compounded with both brain-derived neurotrophic factor- and ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells may demonstrate even better effects in the repair of peripheral nerve injury. We cultured bone marrow mesenchymal stem cells expressing brain-derived neurotrophic factor and/or ciliary neurotrophic factor and used them to treat sciatic nerve injury in rats. We observed an increase in sciatic functional index, triceps wet weight recovery rate, myelin thickness, number of myelinated nerve fibers, amplitude of motor-evoked potentials and nerve conduction velocity, and a shortened latency of motor-evoked potentials when allografts loaded with both neurotrophic factors were used, compared with allografts loaded with just one factor. Thus, the combination of both brain-derived neurotrophic factor and ciliary neurotrophic factor-transfected bone marrow mesenchymal stem cells can greatly improve nerve injury. PMID:26604913

  1. Achilles tendon repair with acellular tissue graft augmentation in neglected ruptures.

    PubMed

    Lee, Daniel K

    2007-01-01

    Neglected Achilles tendon rupture injuries present surgical challenges because of the quality and quantity of tendon tissue during repair combined with the magnitude of mechanical forces placed on this tendon. The purpose of this study was to evaluate the effects of an acellular human dermal tissue matrix, GRAFTJACKET, as an augmentation material in neglected Achilles tendon repair. Nine patients with neglected Achilles tendon ruptures were evaluated and followed up for a minimum of 20 months. Primary repair was followed by augmentation with the graft and suturing circumferentially around the tendon. Patients were placed in an early, functional rehabilitation program with postoperative evaluation at 3, 6, and 12 months. Outcome scores were calculated based on the American Orthopaedic Foot and Ankle Society ankle-hindfoot scoring system. At 20 to 30 months postoperative follow-up range, there has been no incidence of re-rupture or recurrent pain. The average return-to-activity time was 15.2 +/- 1.7 weeks. The results from this retrospective clinical series suggest that using an acellular human dermal tissue matrix to augment neglected Achilles tendon rupture primary repair offers desirable return-to-activity time points and viable surgical alternative over previously reported surgical options. PMID:17980842

  2. Time-dependent bladder tissue regeneration using bilayer bladder acellular matrix graft-silk fibroin scaffolds in a rat bladder augmentation model.

    PubMed

    Zhao, Yang; He, Yi; Zhou, Zhe; Guo, Jian-hua; Wu, Jia-sheng; Zhang, Ming; Li, Wei; Zhou, Juan; Xiao, Dong-dong; Wang, Zhong; Sun, Kang; Zhu, Ying-jian; Lu, Mu-jun

    2015-09-01

    With advances in tissue engineering, various synthetic and natural biomaterials have been widely used in tissue regeneration of the urinary bladder in rat models. However, reconstructive procedures remain insufficient due to the lack of appropriate scaffolding, which should provide a waterproof barrier function and support the needs of various cell types. To address these problems, we have developed a bilayer scaffold comprising a porous network (silk fibroin [SF]) and an underlying natural acellular matrix (bladder acellular matrix graft [BAMG]) and evaluated its feasibility and potential for bladder regeneration in a rat bladder augmentation model. Histological (hematoxylin and eosin and Masson's trichrome staining) and immunohistochemical analyses demonstrated that the bilayer BAMG-SF scaffold promoted smooth muscle, blood vessel, and nerve regeneration in a time-dependent manner. At 12weeks after implantation, bladders reconstructed with the BAMG-SF matrix displayed superior structural and functional properties without significant local tissue responses or systemic toxicity. These results demonstrated that the bilayer BAMG-SF scaffold may be a promising scaffold with good biocompatibility for bladder regeneration in the rat bladder augmentation model. PMID:26049152

  3. Autologous Fat Grafting Improves Facial Nerve Function

    PubMed Central

    Klinger, Marco; Lisa, Andrea; Caviggioli, Fabio; Maione, Luca; Murolo, Matteo; Vinci, Valeriano; Klinger, Francesco Maria

    2015-01-01

    We describe the case of a 45-year-old male patient who presented a retractile and painful scar in the nasolabial fold due to trauma which determined partial motor impairment of the mouth movements. We subsequently treated him with autologous fat grafting according to Coleman's technique. Clinical assessments were performed at 5 and 14 days and 1, 3, and 6 months after surgical procedure and we observed a progressive release of scar retraction together with an important improvement of pain symptoms. A second procedure was performed 6 months after the previous one. We observed total restoration of mimic movements within one-year follow-up. The case described confirms autologous fat grafting regenerative effect on scar tissue enlightening a possible therapeutic effect on peripheral nerve activity, hypothesizing that its entrapment into scar tissue can determine a partial loss of function. PMID:26167327

  4. Healing rates for challenging rotator cuff tears utilizing an acellular human dermal reinforcement graft

    PubMed Central

    Agrawal, Vivek

    2012-01-01

    Purpose: This study presents a retrospective case series of the clinical and structural outcomes (1.5 T MRI) of arthroscopic rotator cuff repair with acellular human dermal graft reinforcement performed by a single surgeon in patients with large, massive, and previously repaired rotator cuff tears. Materials and Methods: Fourteen patients with mean anterior to posterior tear size 3.87 ± 0.99 cm (median 4 cm, range 2.5–6 cm) were enrolled in the study and were evaluated for structural integrity using a high-field (1.5 T) MRI at an average of 16.8 months after surgery. The Constant-Murley scores, the Flexilevel Scale of Shoulder Function (Flex SF), scapular plane abduction, and strength were analyzed. Results: MRI results showed that the rotator cuff repair was intact in 85.7% (12/14) of the patients studied. Two patients had a Sugaya Type IV recurrent tear (2 of 14; 14.3%), which were both less than 1 cm. The Constant score increased from a preoperative mean of 49.72 (range 13–74) to a postoperative mean of 81.07 (range 45–92) (P value = 0.009). Flexilevel Scale of Shoulder Function (Flex SF) Score normalized to a 100-point scale improved from a preoperative mean of 53.69 to a postoperative mean of 79.71 (P value = 0.003). The Pain Score improved from a preoperative mean of 7.73 to a postoperative mean of 13.57 (P value = 0.008). Scapular plane abduction improved from a preoperative mean of 113.64° to a postoperative mean of 166.43° (P value = 0.010). The strength subset score improved from a preoperative mean of 1.73 kg to a postoperative mean of 7.52 kg (P value = 0.006). Conclusions: This study presents a safe and effective technique that may help improve the healing rates of large, massive, and revision rotator cuff tears with the use of an acellular human dermal allograft. This technique demonstrated favorable structural healing rates and statistically improved functional outcomes in the near term. Level of Evidence: 4. Retrospective case series. PMID

  5. Effect of oblique nerve grafting on peripheral nerve regeneration in rats.

    PubMed

    Kotulska, Katarzyna; Marcol, Wiesław; Larysz-Brysz, Magdalena; Tendera, Zofia; Malinowska-Kołodziej, Izabela; Slusarczyk, Wojciech; Jedrzejowska-Szypułka, Halina; Lewin-Kowalik, Joanna

    2006-01-01

    Current methods of peripheral nerve repair are to rejoin cut nerve stumps directly or to bridge large gaps with autologous nerve grafts. In both cases the surface of nerve stump endings is typically cut perpendicularly to the long axis of the nerve. The outcome of such operations, however, is still not satisfactory. In this study, we examine the effect of oblique nerve cutting and grafting on morphological as well as functional features of regeneration. In adult rats, sciatic nerve was cut and rejoined either directly or using an autologous graft, at 90 degrees or 30 degrees angle. Functional regeneration was assessed by walking track analysis during 12-week follow-up. Afterwards muscle weight was measured and histological studies were performed. The latter included nerve fibers and Schwann cells counting, as well as visualization of scar formation and epineural fibrosis. Nerves cut obliquely and rejoined showed better functional recovery than perpendicularly transected. Similar effect was observed after oblique grafting when compared to perpendicular one. Numbers of nerve fibers growing into the distal stump of the nerve as well as the number of Schwann cells were significantly higher in obliquely than in perpendicularly operated nerves. Moreover, growing axons were arranged more regularly following oblique treatment. These data indicate that joining or grafting the nerve stumps at acute angle is a more profitable method of nerve repair than the standard procedure performed at right angle. PMID:17066410

  6. Root Coverage in Smokers with Acellular Dermal Matrix Graft and Enamel Matrix Derivative: A 12-Month Randomized Clinical Trial.

    PubMed

    Costa, Priscila Paganini; Alves, Luciana Bastos; Souza, Sérgio Luís; Grisi, Márcio Fernando; Palioto, Daniela Bazan; Taba, Mario; Novaes, Arthur Belém

    2016-01-01

    This study investigated whether enamel matrix derivative (EMD) contributes to root coverage of gingival recessions performed with acellular dermal matrix graft (ADMG) in smokers during a 12-month follow-up. A sample of 19 smokers presenting bilateral Miller Class I or II gingival recessions were included. Selected sites randomly received both ADMG and EMD (test) or ADMG alone (control). Probing depth, clinical attachment level, gingival recession height, keratinized tissue, and root coverage were evaluated. Mean gain in recession height (P < .05), sites with complete root coverage (P < .05), and percentage of root coverage (59.7% and 52.8%, respectively) favored the test group compared with the control group. PMID:27333010

  7. Bi-linear mechanical property determination of acellular human patellar tendon grafts for use in anterior cruciate ligament replacement.

    PubMed

    Herbert, Anthony; Brown, Christopher; Rooney, Paul; Kearney, John; Ingham, Eileen; Fisher, John

    2016-06-14

    Anterior cruciate ligament rupture is rising in its prevalence amongst the young and those with physically active lifestyles. Acellular human patellar tendon (PT) grafts offer a promising restoration solution, returning knee joint stability and overcoming some of the current disadvantages of autologous or allogeneic grafts. However, it is necessary to ensure that the decellularisation bio-processes involved do not cause structural changes in the microstructure of the tendon tissue that may adversely affect the mechanical properties, particularly with respect to the physiological range of loading. Sixteen cadaveric human PT grafts were sourced and processed from eight donors, with full ethical approval and consent for use in research. Eight specimens were allocated for decellularisation, while the remaining eight contralateral specimens were used as native controls. Testing consisted of 12 preconditioning cycles followed by uniaxial extension until failure occurred. Stress-strain data was then fitted to a bi-linear model using least squares regression by a custom-written Matlab script. The elastic moduli for the toe region and linear region of each specimen were determined, in addition to the transition point co-ordinates and strain energy density for increasing strain. No significant differences were found between groups for all of the parameters investigated. Hence, the shape and magnitude of the stress-strain profile was found to be the same for both groups throughout loading. The results of this study indicated that decellularisation appeared to have no effect on the material properties of human PT grafts under quasistatic conditions. Therefore, acellular human PT grafts can offer a viable additional solution for ACL replacement compared to current autologous and allogeneic treatment options. PMID:27063250

  8. Axillary Nerve Reconstruction: Anterior-Posterior Exposure With Sural Nerve Cable Graft Pull-Through Technique.

    PubMed

    Baltzer, Heather L; Spinner, Robert J; Bishop, Allen T; Shin, Alexander Y

    2015-12-01

    Deltoid paralysis after axillary nerve injury results in limitations in shoulder function and stability. In the setting of an isolated axillary nerve injury with no clinical or electromyographic evidence of recovery that is within 6 to 9 months postinjury, the authors' preferred technique to reinnervate the deltoid is to reconstruct the axillary nerve with sural nerve grafting. Intraoperative neuromuscular electrophysiology is critical to determine the continuity of the axillary nerve before proceeding with reconstruction. The majority of the time, both an anterior and posterior incision and dissection of the axillary nerve is required to adequately delineate the zone of injury. This also ensures that both proximally and distally, uninjured axillary nerve is present before graft inset and also facilitates the ability to perform a meticulous microsurgical inset of the nerve graft posteriorly. The nerve graft must be pulled through from posterior to anterior to span the zone of injury and reconstruct the axillary nerve. Careful infraclavicular brachial plexus dissection is necessary to prevent further injury to components of the brachial plexus in the setting of a scarred bed. Patients will require postoperative therapy to prevent limitations in shoulder range of motion secondary to postoperative stiffness. This paper presents a detailed surgical technique for axillary nerve reconstruction by an anterior-posterior approach with a pull-through technique of a sural nerve cable graft. PMID:26524659

  9. Use of superficial peroneal nerve graft for treating peripheral nerve injuries☆

    PubMed Central

    Ribak, Samuel; da Silva Filho, Paulo Roberto Ferreira; Tietzmann, Alexandre; Hirata, Helton Hiroshi; de Mattos, Carlos Augusto; da Gama, Sérgio Augusto Machado

    2016-01-01

    Objective To evaluate the clinical results from treating chronic peripheral nerve injuries using the superficial peroneal nerve as a graft donor source. Methods This was a study on eleven patients with peripheral nerve injuries in the upper limbs that were treated with grafts from the sensitive branch of the superficial peroneal nerve. The mean time interval between the dates of the injury and surgery was 93 days. The ulnar nerve was injured in eight cases and the median nerve in six. There were three cases of injury to both nerves. In the surgery, a longitudinal incision was made on the anterolateral face of the ankle, thus viewing the superficial peroneal nerve, which was located anteriorly to the extensor digitorum longus muscle. Proximally, the deep fascia between the extensor digitorum longus and the peroneal longus muscles was dissected. Next, the motor branch of the short peroneal muscle (one of the branches of the superficial peroneal nerve) was identified. The proximal limit of the sensitive branch was found at this point. Results The average space between the nerve stumps was 3.8 cm. The average length of the grafts was 16.44 cm. The number of segments used was two to four cables. In evaluating the recovery of sensitivity, 27.2% evolved to S2+, 54.5% to S3 and 18.1% to S3+. Regarding motor recovery, 72.7% presented grade 4 and 27.2% grade 3. There was no motor deficit in the donor area. A sensitive deficit in the lateral dorsal region of the ankle and the dorsal region of the foot was observed. None of the patients presented complaints in relation to walking. Conclusions Use of the superficial peroneal nerve as a graft source for treating peripheral nerve injuries is safe and provides good clinical results similar to those from other nerve graft sources. PMID:26962502

  10. Nerve Wrapping of the Sciatic Nerve With Acellular Dermal Matrix in Chronic Complete Proximal Hamstring Ruptures and Ischial Apophyseal Avulsion Fractures

    PubMed Central

    Haus, Brian M.; Arora, Danny; Upton, Joseph; Micheli, Lyle J.

    2016-01-01

    Background: Patients with chronic injuries of the proximal hamstring can develop significant impairment because of weakness of the hamstring muscles, sciatic nerve compression from scar formation, or myositis ossificans. Purpose: To describe the surgical outcomes of patients with chronic injury of the proximal hamstrings who were treated with hamstring repair and sciatic neurolysis supplemented with nerve wrapping with acellular dermal matrix. Study Design: Retrospective case series; Level of evidence, 4. Methods: Fifteen consecutive patients with a diagnosis of chronic complete proximal hamstring rupture or chronic ischial tuberosity apophyseal avulsion fracture (mean age, 39.67 years; range, 14-69 years) were treated with proximal hamstring repair and sciatic neurolysis supplemented with nerve wrapping with acellular dermal matrix. Nine patients had preoperative sciatica, and 6 did not. Retrospective chart review recorded clinical outcomes measured by the degree of pain relief, the rate of return to activities, and associated postoperative complications. Results: All 15 patients were followed in the postoperative period for an average of 16.6 months. Postoperatively, there were 4 cases of transient sciatic nerve neurapraxia. Four patients (26%) required postoperative betamethasone sodium phosphate (Celestone Soluspan) injectable suspension USP 6 mg/mL. Among the 9 patients with preoperative sciatica, 6 (66%) had a good or excellent outcome and were able to return to their respective activities/sports; 3 (33%) had persistent chronic pain. One of these had persistent sciatic neuropathy that required 2 surgical reexplorations and scar excision after development of recurrent extraneural scar formation. Among the 6 without preoperative sciatica, 100% had a good or excellent outcomes and 83% returned to their respective activities/sports. Better outcomes were observed in younger patients, as the 3 cases of persistent chronic sciatic pain were in patients older than 45

  11. Use of Vein Conduit and Isolated Nerve Graft in Peripheral Nerve Repair: A Comparative Study

    PubMed Central

    Ahmad, Imran; Akhtar, Md. Sohaib

    2014-01-01

    Aims and Objectives. The aim of this study was to evaluate the effectiveness of vein conduit in nerve repair compared with isolated nerve graft. Materials and Methods. This retrospective study was conducted at author's centre and included a total of 40 patients. All the patients had nerve defect of more than 3 cm and underwent nerve repair using nerve graft from sural nerve. In 20 cases, vein conduit (study group) was used whereas no conduit was used in other 20 cases. Patients were followed up for 2 years at the intervals of 3 months. Results. Patients had varying degree of recovery. Sensations reached to all the digits at 1 year in study groups compared to 18 months in control group. At the end of second year, 84% patients of the study group achieved 2-point discrimination of <10 mm compared to 60% only in control group. In terms of motor recovery, 82% patients achieved satisfactory hand function in study group compared to 56% in control group (P < .05). Conclusions. It was concluded that the use of vein conduit in peripheral nerve repair is more effective method than isolated nerve graft providing good sensory and motor recovery. PMID:25405029

  12. Bovine Dermal Matrix as Coverage of Facial Nerve Grafts

    PubMed Central

    Kappos, E. A.; Engels, P. E.; Wettstein, R.; Schaefer, D. J.; Kalbermatten, D. F.

    2014-01-01

    Introduction. Soft tissue defects over functional structures represent a challenge for the reconstructive surgeon. Often complex, reconstructive procedures are required. Occasionally, elderly or sick patients do not qualify for these extensive procedures. Case. We present the case of a 91-year-old lady with large hemifacial defect with exposed bone and nerves after tumor resection. We first performed radical resection including the fascia of the temporalis muscle and the frontal branch of the facial nerve. Due to the moribund elderly patient with a potentially high perioperative risk, we decided against flap reconstruction but to use bovine collagen/elastin matrix and split thickness skin graft. Results. No postoperative complications occurred and STSG and matrix healed uneventfully. Discussion. In selected cases, where complex reconstruction is not appropriate, this procedure can be a safe, easy, and fast alternative for covering soft tissue defects even on wound grounds containing nerve grafts. PMID:24550990

  13. Comparison of divided sciatic nerve growth within dermis, venous and nerve graft conduit in rat

    PubMed Central

    Fatemi, Mohammad Javad; Foroutan, Kamal Seyed; Ashtiani, Abass Kazemi; Mansoori, Maryam Jafari; Vaghardoost, Reza; Pedram, Sepehr; Hosseinpolli, Aidin; Rajabi, Fatemeh; Mousavi, Seyed Jaber

    2010-01-01

    BACKGROUND: Considering the common origin of skin and peripheral nervous system, a tube of dermal layer of skin hypothetically can be an ideal conduit for nerve reconstruction. An experimental study performed to evaluate the nerve regeneration of efficacy into a dermal tube. METHODS: Sixty male Wistar rats were used. A 10 mm gap was produced in right sciatic nerves. In group A the autogenous nerve grafts were used to bridge the defects. In group B vein conduit were use to reconstruct the gaps. In group C dermal tube were used to bridge the defects. Morphologic studies were carried out after 3 month. RESULTS: The density of nerve fibers was significantly higher in autogenous nerve graft group. The efficacy of nerve growth into the dermal tube group was significantly poor in comparison to other groups. CONCLUSIONS: In the present study, dermis was used as the nerve conduit for the first time. This study indicates that the dermal tube is not a suitable conduit for nerve regeneration till further studies to resolve the problems before clinical application. PMID:21526083

  14. The development of a normalization method for comparing nerve regeneration effectiveness among different graft types

    PubMed Central

    Chang, Wei; DeVince, Jeffrey; Green, Gabriella; Shah, Munish B.; Johns, Michael S.; Meng, Yan; Yu, Xiaojun

    2013-01-01

    The inability to compare directly different nerve grafts has been a significant factor hindering the advance of nerve graft development. Due to the abundance of variables that exist in nerve graft construction and multiple assessment types, there has been limited success in comparing nerve graft effectiveness among experiments. Using mathematical techniques on nerve conduction velocity (NCV) autograft data, a normalization function was empirically derived that normalizes differences in gap lengths. Further analysis allowed for the development of the Relative Regeneration Ratio (RRR). The RRR function allows researchers to directly compare nerve graft results based on the NCV data from their respective studies as long as the data was collected at the same post-operation time. This function also allows for comparisons between grafts tested at different gap lengths. Initial testing of this RRR function provided confidence that the function is accurate for a continuum of gap lengths and different nerve graft types. PMID:24118184

  15. Epithelial-differentiated adipose-derived stem cells seeded bladder acellular matrix grafts for urethral reconstruction: an animal model.

    PubMed

    Li, Hongbin; Xu, Yuemin; Xie, Hong; Li, Chao; Song, Lujie; Feng, Chao; Zhang, Qin; Xie, Minkai; Wang, Ying; Lv, Xiangguo

    2014-02-01

    The limited amount of available epithelial tissue is considered a main cause of the high rate of urethral reconstruction failures. The aim of this study was to investigate whether epithelial-differentiated rabbit adipose-derived stem cells (Epith-rASCs) could play a role of epithelium in vivo functionally and be a potential substitute of urothelium. Substitution urethroplasty was performed to repair an anterior urethral defect in male New Zealand rabbits using Epith-rASCs seeded bladder acellular matrix grafts (BAMGs) after 5-bromo-2'-deoxyuridine (BrdU) labeling, based on the in vitro epithelial induction system we previously described. Urethroplasty with cell-free BAMGs and with undifferentiated rASCs (Und-rASCs) seeded BAMGs were performed as controls. After surgery, a notable amelioration of graft contracture and recovery of urethral continuity were observed in the Epith-rASCs/BAMG group by retrograde urethrograms and macroscopic inspection. Immunofluorescence revealed that the BrdU-labeled Epith-rASCs/Und-rASCs colocalized with cytokeratin 13 or myosin. Consistent with the results of western blotting, at early postimplantation stage, the continuous epithelial layer with local multilayered structure was observed in the Epith-rASCs/BAMG group, whereas no significant growth and local monolayer growth profile of epithelial cells were observed in the BAMG and Und-rASCs/BAMG group, respectively. The results showed that Epith-rASCs could serve as a potential substitute of urothelium for urethral tissue engineering and be available to prevent lumen contracture and subsequent complications including recurrent stricture. PMID:24329501

  16. Effectively Axonal-supercharged Interpositional Jump-Graft with an Artificial Nerve Conduit for Rat Facial Nerve Paralysis

    PubMed Central

    Niimi, Yosuke; Takeuchi, Yuichi; Sasaki, Ryo; Watanabe, Yorikatsu; Yamato, Masayuki; Miyata, Mariko; Sakurai, Hiroyuki

    2015-01-01

    Background: Interpositional jump graft (IPJG) is a nerve graft axonally supercharged from the hypoglossal nerve. However, for using the technique, an autologous nerve, which should contain the great auricular and sural nerves, must be obtained. Depending on the donor site, unavoidable issues such as nerve disorders and postoperative scarring may appear. To reduce the issues, in this study, the authors developed an end-to-side neurorrhaphy technique with the recipient nerve and an artificial nerve conduit and investigated the efficacy of an IPJG with an artificial nerve conduit in a rat facial nerve paresis model. Methods: A ligature clip was used to crush the facial nerve trunk, thereby creating a partial facial nerve paresis model. An artificial nerve conduit was then prepared with a 10-mm-long silicone tube containing 10 μL type I collagen and used to create an IPJG between the facial nerve trunk and the hypoglossal nerve (the silicone tube group). Thirteen weeks after the surgery, the outcome was histologically and physiologically compared with conventional IPJG with autograft using the great auricular nerve. Results: Retrograde tracer test confirmed a double innervation by the facial and hypoglossal nerve nuclei. In the autograft and silicone tube groups, the regeneration of myelinated axons was observed. Conclusion: In this study, the authors successfully developed an end-to-side neurorrhaphy technique with the recipient nerve and an artificial nerve conduit, and revealed that an IPJG in the conduit was effective in the rat facial nerve paresis model. PMID:26180717

  17. Long-term in vivo regeneration of peripheral nerves through bioengineered nerve grafts.

    PubMed

    di Summa, P G; Kalbermatten, D F; Pralong, E; Raffoul, W; Kingham, P J; Terenghi, G

    2011-05-01

    Although autologous nerve graft is still the first choice strategy in nerve reconstruction, it has the severe disadvantage of the sacrifice of a functional nerve. Cell transplantation in a bioartificial conduit is an alternative strategy to improve nerve regeneration. Nerve fibrin conduits were seeded with various cell types: primary Schwann cells (SC), SC-like differentiated bone marrow-derived mesenchymal stem cells (dMSC), SC-like differentiated adipose-derived stem cells (dASC). Two further control groups were fibrin conduits without cells and autografts. Conduits were used to bridge a 1 cm rat sciatic nerve gap in a long term experiment (16 weeks). Functional and morphological properties of regenerated nerves were investigated. A reduction in muscle atrophy was observed in the autograft and in all cell-seeded groups, when compared with the empty fibrin conduits. SC showed significant improvement in axon myelination and average fiber diameter of the regenerated nerves. dASC were the most effective cell population in terms of improvement of axonal and fiber diameter, evoked potentials at the level of the gastrocnemius muscle and regeneration of motoneurons, similar to the autografts. Given these results and other advantages of adipose derived stem cells such as ease of harvest and relative abundance, dASC could be a clinically translatable route towards new methods to enhance peripheral nerve repair. PMID:21371534

  18. The vascularized sural nerve graft based on a peroneal artery perforator for reconstruction of the inferior alveolar nerve defect.

    PubMed

    Hayashida, Kenji; Hiroto, Saijo; Morooka, Shin; Kuwabara, Kaoru; Fujioka, Masaki

    2015-03-01

    The sural nerve has been described for nerve reconstruction of the maxillofacial region since it provides many advantages. We report a case of a vascularized sural nerve graft based on a peroneal artery perforator for immediate reconstruction after the removal of intraosseous neuroma originating in the inferior alveolar nerve. The patient had a neuroma caused by iatrogenic injury to the inferior alveolar nerve. A 4-cm long neuroma existed in the inferior alveolar nerve and was resected. A peroneal perforator was chosen as the pedicle of the vascularized sural nerve graft for the nerve gap. The graft including the skin paddle for monitoring the perfusion supplied by this perforator was transferred to the lesion. The nerve gap between the two stumps of the inferior alveolar nerve was repaired using the 6-cm long vascularized sural nerve. The perforator of the peroneal artery was anastomosed to the branch of the facial artery in a perforator-to-perforator fashion. There was no need to sacrifice any main arteries. The skin paddle with 1 cm × 3 cm in size was inset into the incised medial neck. Perceptual function tests with a Semmes-Weinstein pressure esthesiometer and two-point discrimination in the lower lip and chin at 10 months after surgery showed recovery almost to the level of the normal side. This free vascularized sural nerve graft based on a peroneal artery perforator may be a good alternative for reconstruction of inferior alveolar nerve defects. PMID:25346479

  19. Regeneration of respiratory pathways within spinal peripheral nerve grafts.

    PubMed

    Decherchi, P; Lammari-Barreault, N; Gauthier, P

    1996-01-01

    Central respiratory neurons exhibit normal activity after axonal regeneration within blind-ended peripheral nerve grafts (PNGs) inserted near the corresponding cell bodies in the medullary respiratory centers. Part of these medullary respiratory neurons project toward the spinal cord and contribute to descending respiratory pathways that control respiratory motoneurons. The present work investigates to what extent cervical respiratory pathways could be directed out of the central nervous system within PNGs inserted distant to the medullary respiratory nuclei. In adult rats (n = 13), autologous segments of the peroneal nerve were implanted into the ventrolateral part of the C2 spinal cord at the level of the descending respiratory pathways. Two to four months after grafting, electrophysiological recording of teased graft filaments (n = 562) revealed the presence of regenerated nerve fibers with unitary impulse traffic (n = 164) in all tested PNGs (n = 6). Respiratory discharges (n = 52) corresponded to efferent and afferent activity. Efferent respiratory discharges (n = 32) originated from central respiratory neurons which remained functional and preserved afferent connections. Retrograde horseradish peroxidase labeling applied to the distal cut end of PNGs (n = 7) revealed stained (42/1997) neurons in areas where respiratory cells have been described. Afferent respiratory discharges (n = 20) were synchronized with lung inflation but their origin (stretch pulmonary receptors and/or respiratory muscle receptors) was not determined. On the basis of additional data from light and electron microscopy of PNGs, comparison was made between anatomical, retrograde labeling, and electrophysiological data. The main conclusion is that spinal PNGs appear to be able to promote axonal regeneration of functional respiratory efferent and afferent pathways. PMID:8566201

  20. Tissue specificity in rat peripheral nerve regeneration through combined skeletal muscle and vein conduit grafts.

    PubMed

    Tos, P; Battiston, B; Geuna, S; Giacobini-Robecchi, M G; Hill, M A; Lanzetta, M; Owen, E R

    2000-01-01

    Diffusible factors from the distal stumps of transected peripheral nerves exert a neurotropic effect on regenerating nerves in vivo (specificity). This morphological study was designed to investigate the existence of tissue specificity in peripheral nerve fiber regeneration through a graft of vein filled with fresh skeletal muscle. This tubulization technique demonstrated experimental and clinical results similar to those obtained with traditional autologous nerve grafts. Specifically, we used Y-shaped grafts to assess the orientation pattern of regenerating axons in the distal stump tissue. Animal models were divided into four experimental groups. The proximal part of the Y-shaped conduit was sutured to a severed tibial nerve in all experiments. The two distal stumps were sutured to different targets: group A to two intact nerves (tibial and peroneal), group B to an intact nerve and an unvascularized tendon, group C to an intact nerve and a vascularized tendon, and group D to a nerve graft and an unvascularized tendon. Morphological evaluation by light and electron microscopy was conducted in the distal forks of the Y-shaped tube. Data showed that almost all regenerating nerve fibers spontaneously oriented towards the nerve tissue (attached or not to the peripheral innervation field), showing a good morphological pattern of regeneration in both the early and late phases of regeneration. When the distal choice was represented by a tendon (vascularized or not), very few nerve fibers were detected in the corresponding distal fork of the Y-shaped graft. These results show that, using the muscle-vein-combined grafting technique, regenerating axons are able to correctly grow and orientate within the basement membranes of the graft guided by the neurotropic lure of the distal nerve stump. PMID:10702739

  1. Acellular Dermal Matrix Combined with Autologous Skin Grafts for Closure of Chronic Wounds after Reconstruction of Skull Defects with Titanium Mesh.

    PubMed

    Luo, Xu; Lin, Cai; Wang, Xinling; Lin, Xiangwei; He, Sunyue; Liu, Yunfeng; Zhang, Yong; Yang, Ruijin; Zhu, Xinguo

    2016-07-01

    Objective The closure of chronic wounds after skull defect reconstruction with titanium mesh is one of the most challenging problems for plastic and reconstructive surgeons. Current approaches are disappointing. Methods In 10 patients, we explored the role of acellular dermal matrix (ADM) in combination with autologous skin grafts (ASGs) for closure of chronic wounds after skull reconstruction with titanium. Results ADM and ASG survived in all patients. Grade A healing (healing well without defect) was achieved. The average operating time was 30 to 45 minutes, and the average blood loss 30 to 50 mL. After 3 months, the wound was still closed in all patients. Conclusion The combination of ADM plus ASG obtained a high wound closure rate. ADM plus ASG allows avoiding other procedures such as rotational flaps and free flaps that require more operating time, special equipment, and adequate training. PMID:27088591

  2. Results of nerve grafting in radial nerve injuries occurring proximal to the humerus, including those within the posterior cord.

    PubMed

    Bertelli, Jayme Augusto; Ghizoni, Marcos Flávio

    2016-01-01

    OBJECT Results of radial nerve grafting are largely unknown for lesions of the radial nerve that occur proximal to the humerus, including those within the posterior cord. METHODS The authors describe 13 patients with proximal radial nerve injuries who were surgically treated and then followed for at least 24 months. The patients' average age was 26 years and the average time between accident and surgery was 6 months. Sural nerve graft length averaged 12 cm. Recovery was scored according to the British Medical Research Council (BMRC) scale, which ranges from M0 to M5 (normal muscle strength). RESULTS After grafting, all 7 patients with an elbow extension palsy recovered elbow extension, scoring M4. Six of the 13 recovered M4 wrist extension, 6 had M3, and 1 had M2. Thumb and finger extension was scored M4 in 3 patients, M3 in 2, M2 in 2, and M0 in 6. CONCLUSIONS The authors consider levels of strength of M4 for elbow and wrist extension and M3 for thumb and finger extension to be good results. Based on these criteria, overall good results were obtained in only 5 of the 13 patients. In proximal radial nerve lesions, the authors now advocate combining nerve grafts with nerve or tendon transfers to reconstruct wrist, thumb, and finger extension. PMID:26274998

  3. Maxillary sinus augmentation using recombinant bone morphogenetic protein-2/acellular collagen sponge in combination with a mineralized bone replacement graft: a report of three cases.

    PubMed

    Tarnow, Dennis P; Wallace, Stephen S; Testori, Tiziano; Froum, Stuart J; Motroni, Alessandro; Prasad, Hari S

    2010-04-01

    The objective of the following case reports was to assess whether mineralized bone replacement grafts (eg, xenografts and allografts) could be added to recombinant human bone morphogenetic protein-2/acellular collagen sponge (rhBMP-2/ACS) in an effective manner that would: (1) reduce the graft shrinkage observed when using rhBMP-2/ACS alone, (2) reduce the volume and dose of rhBMP-2 required, and (3) preserve the osteoinductivity that rhBMP-2/ACS has shown when used alone. The primary outcome measures were histomorphometric analysis of vital bone production and analysis of serial computed tomographic scans to determine changes in bone graft density and stability. Over the 6-month course of this investigation, bone graft densities tended to increase (moreso with the xenograft than the allograft). The increased density in allograft cases was likely the result of both compression of the mineralized bone replacement graft and vital bone formation, seen histologically. Loss of volume was greater with the four-sponge dose than the two-sponge dose because of compression and resorption of the sponges. Vital bone formation in the allograft cases ranged from 36% to 53% but, because of the small sample size, it was not possible to determine any significant difference between the 5.6 mL (four-sponge) dose and the 2.8 mL (two-sponge) dose. Histology revealed robust new woven bone formation with only minimal traces of residual allograft, which appeared to have undergone accelerated remodeling or rhBMP-2-mediated resorption. PMID:20228973

  4. Vascularized Nerve Bypass Graft: A Case Report of an Additional Treatment for Poor Sensory Recovery.

    PubMed

    Usami, Satoshi; Tanaka, Kentaro; Ohkubo, Alisa; Okazaki, Mutsumi

    2016-04-01

    End-to-side neurorrhaphy has proven effective in basic research and in clinical application. One of the methods of end-to-side neurorrhaphy, nerve bypass technique, has been reported and axon regeneration has been proven. In clinical application, the utility of the nerve bypass technique has been revealed in some cases; however, these bypasses were performed using nonvascularized nerves. We initially used the vascularized nerve bypass graft technique with the sural nerve as a secondary clinical procedure after median nerve injury in a 61-year-old patient and achieved motor and sensory nerve regeneration, as supported by a nerve conduction study and clinical sensory test. This technique has the potential to become one of the choices for salvage procedure of severe nerve injury. PMID:27200248

  5. Vascularized Nerve Bypass Graft: A Case Report of an Additional Treatment for Poor Sensory Recovery

    PubMed Central

    Tanaka, Kentaro; Ohkubo, Alisa; Okazaki, Mutsumi

    2016-01-01

    Summary: End-to-side neurorrhaphy has proven effective in basic research and in clinical application. One of the methods of end-to-side neurorrhaphy, nerve bypass technique, has been reported and axon regeneration has been proven. In clinical application, the utility of the nerve bypass technique has been revealed in some cases; however, these bypasses were performed using nonvascularized nerves. We initially used the vascularized nerve bypass graft technique with the sural nerve as a secondary clinical procedure after median nerve injury in a 61-year-old patient and achieved motor and sensory nerve regeneration, as supported by a nerve conduction study and clinical sensory test. This technique has the potential to become one of the choices for salvage procedure of severe nerve injury. PMID:27200248

  6. In vivo application of poly-3-hydroxyoctanoate as peripheral nerve graft

    PubMed Central

    Hazer, D. Burcu; Bal, Ercan; Nurlu, Gülay; Benli, Kemal; Balci, Serdar; Öztürk, Feral; Hazer, Baki

    2013-01-01

    Objective: This study aims to investigate the degree of biocompatibility and neuroregeneration of a polymer tube, poly-3-hydroxyoctanoate (PHO) in nerve gap repair. Methods: Forty Wistar Albino male rats were randomized into two groups: autologous nerve gap repair group and PHO tube repair group. In each group, a 10-mm right sciatic nerve defect was created and reconstructed accordingly. Neuroregeneration was studied by sciatic function index (SFI), electromyography, and immunohistochemical studies on Days 7, 21, 45 and 60 of implantation. Biocompatibility was analyzed by the capsule formation around the conduit. Biodegradation was analyzed by the molecular weight loss in vivo. Results: Electrophysiological and histomorphometric assessments demonstrated neuroregeneration in both groups over time. In the experimental group, a straight alignment of the Schwann cells parallel to the axons was detected. However, autologous nerve graft seems to have a superior neuroregeneration compared to PHO grafts. Minor biodegradation was observed in PHO conduit at the end of 60 d. Conclusions: Although neuroregeneration is detected in PHO grafts with minor degradation in 60 d, autologous nerve graft is found to be superior in axonal regeneration compared to PHO nerve tube grafts. PHO conduits were found to create minor inflammatory reaction in vivo, resulting in good soft tissue response. PMID:24190445

  7. Human nerve xenografting in nude mouse: Experimental study of graft revascularization

    SciTech Connect

    Duprez, K.; Bour, C.; Merle, M.; Duprez, A. )

    1991-01-01

    In the nude mouse, the congenital absence of T lymphocytes makes it possible to implant human nerve grafts without rejection or iatrogenic modifications (by immunosuppression) of human and murine tissues. Medial antebrachial cutaneous nerves were harvested from human cadavers 1-18 hours after death. These nerve grafts were implanted using different techniques in nude mice. All the grafts were macroscopically and microscopically revascularized 3 days after implantation. The modifications in time of this vascularization could be studied with precision through the use of repeated biopsies. The absence of human blood group antigens on the neovessel endothelium suggested a murine origin for angiogenesis. In situ DNA hybridizations with human and mouse DNA confirmed this origin. The topography of the revascularization (maximal in the perineurium and endoneurium) and the almost complete absence of human cells other than Schwann cells in the grafts at the peak of angiogenesis (26 days after grafting) suggested that Schwann cells had a determining role in graft vascularization. The irradiation of the nerve grafts with a dose of 30 grays before implantation did not modify significantly their histologic appearance compared to the control group, whereas an irradiation of 60 grays led to massive lesions. The neurotization of murine axons led to chimerical structures of normal histologic appearance, with vascularization similar to that observed in nonneurotized nerves. Through chimerism (human Schwann cells, murine vessels and axons) this model makes it possible to dissociate the respective role of the host and of the nerve graft in angiogenesis and suggests the existence of growth factors produced by the human Schwann cells.

  8. A Comparison of Acellular Dermal Matrix Allograft and Periosteal Pedicle Graft Covered by Coronally Advanced Flap in the Treatment of Gingival Recession: 1-Year Follow-Up Study.

    PubMed

    Godavarthi, Lalasa; Murthy, K Raja; Pavankumar, Sandhya

    2016-01-01

    The objective of this study was to evaluate and compare the clinical efficacy of periosteal pedicle graft (PPG) and acellular dermal matrix allograft (ADMA) in conjunction with coronally advanced flap (CAF) in the treatment of gingival recession during a 1-year follow-up. A sample of 14 patients, each with two similar Miller Class I or II gingival recession (28 recession sites), was selected. Each recession site was randomly assigned to the experimental site (PPG + CAF) or the control site (ADMG + CAF). The clinical parameters recorded at baseline and 12 months postoperatively were probing pocket depth, width of keratinized gingiva, and clinical attachment level, whereas full-mouth and site-specific plaque and gingival index and vertical recession depth and width were recorded at baseline and at 1, 3, 6, 9, and 12 months. Analysis was performed to determine if treatment differences were present. The mean recession depth in experimental sites decreased from 2.89 ± 0.40 mm at baseline to 0.25 ± 0.50 mm at 12 months, corresponding to a mean root coverage of 92.79% ± 14.25%. In control sites, recession shrank from 2.93 ± 0.55 mm at baseline to 0.32 ± 0.46 mm at 12 months follow-up, demonstrating a mean root coverage of 89.79% ± 14.73%. Compared to the use of ADMA, the PPG technique uses similar incision design and flap management at the graft site, is equivalent in technique sensitivity, and has a perceived improvement in esthetic outcome. PMID:27333020

  9. Synergist muscle ablation and recovery from nerve-repair grafting: contractile and metabolic function

    PubMed Central

    Larkin, Lisa M.; Kuzon, William M.; Halter, Jeffrey B.

    2009-01-01

    After nerve-repair grafting of medial gastrocnemius muscle, there is incomplete recovery of specific force and sustainable power, perhaps due to overcompensation by synergistic muscles. We hypothesized that increased workload due to synergist ablation would enhance graft recovery. Contractile and metabolic properties of control and nerve-repair grafted muscles, with and without synergist ablation, were determined after 120 days recovery. Specific force (N/cm2) and normalized power (W/kg) were less in the experimental groups compared with controls. Sustained power (W/kg) in the synergist-ablated nerve-repair grafted muscle was higher than nerve-repair grafted muscle, returning to control values. GLUT-4 protein was higher and glycogen content was diminished in both synergist-ablated groups. In summary, synergist ablation did not enhance the recovery of specific force or normalized power, but sustained power did recover, suggesting that metabolic and not mechanical parameters were responsible for this recovery. The enhanced endurance after synergist ablation was accompanied by increased GLUT-4 protein, suggesting a role for increased uptake of circulating glucose during contraction. PMID:11007584

  10. Peripheral Nerve Grafts after Cervical Spinal Cord Injury in Adult Cats

    PubMed Central

    Côté, Marie-Pascale; Hanna, Amgad; Lemay, Michel A.; Ollivier-Lanvin, Karen; Santi, Lauren; Miller, Kassi; Monaghan, Rebecca; Houlé, John D.

    2010-01-01

    Peripheral nerve grafts (PNG) into the rat spinal cord support axon regeneration after acute or chronic injury, with synaptic reconnection across the lesion site and some level of behavioral recovery. Here, we grafted a peripheral nerve into the injured spinal cord of cats as a preclinical treatment approach to promote regeneration for eventual translational use. Adult female cats received a partial hemisection lesion at the cervical level (C7) and immediate apposition of an autologous tibial nerve segment to the lesion site. Five weeks later, a dorsal quadrant lesion was performed caudally (T1), the lesion site treated with Chondroitinase ABC two days later to digest growth inhibiting extracellular matrix molecules, and the distal end of the PNG apposed to the injury site. After 4–20 weeks, the grafts survived in 10/12 animals with several thousand myelinated axons present in each graft. The distal end of 9/10 grafts was well apposed to the spinal cord and numerous axons extended beyond the lesion site. Intraspinal stimulation evoked compound action potentials in the graft with an appropriate latency illustrating normal axonal conduction of the regenerated axons. Although stimulation of the PNG failed to elicit responses in the spinal cord distal to the lesion site, the presence of c-Fos immunoreactive neurons close to the distal apposition site indicates that regenerated axons formed functional synapses with host neurons. This study demonstrates the successful application of a nerve grafting approach to promote regeneration after spinal cord injury in a non-rodent, large animal model. PMID:20599980

  11. Rat sciatic nerve reconstruction across a 30 mm defect bridged by an oriented porous PHBV tube with Schwann cell as artificial nerve graft.

    PubMed

    Karimi, Mina; Biazar, Esmaeil; Keshel, Saeed Heidari; Ronaghi, Abdolaziz; Doostmohamadpour, Jafar; Janfada, Alireza; Montazeri, Arash

    2014-01-01

    An oriented poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit has been used to evaluate its efficiency based on the promotion of peripheral nerve regeneration in rats. The oriented porous micropatterned artificial nerve conduit was designed onto the micropatterned silicon wafers, and then their surfaces were modified with oxygen plasma to increase cell adhesion. The designed conduits were investigated by cell culture analyses with Schwann cells (SCs). The conduits were implanted into a 30 mm gap in sciatic nerves of rats. Four months after surgery, the regenerated nerves were monitored and evaluated by macroscopic assessments and histology and behavioral analyses. Results of cellular analyses showed suitable properties of designed conduit for nerve regeneration. The results demonstrated that in the polymeric graft with SCs, the rat sciatic nerve trunk had been reconstructed with restoration of nerve continuity and formatted nerve fibers with myelination. Histological results demonstrated the presence of Schwann and glial cells in regenerated nerves. Functional recovery such as walking, swimming, and recovery of nociceptive function was illustrated for all the grafts especially conduits with SCs. This study proves the feasibility of the artificial nerve graft filled with SCs for peripheral nerve regeneration by bridging a longer defect in an animal model. PMID:24399063

  12. Rat Sciatic Nerve Reconstruction Across a 30 mm Defect Bridged by an Oriented Porous PHBV Tube With Schwann Cell as Artificial Nerve Graft

    PubMed Central

    2014-01-01

    An oriented poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit has been used to evaluate its efficiency based on the promotion of peripheral nerve regeneration in rats. The oriented porous micropatterned artificial nerve conduit was designed onto the micropatterned silicon wafers, and then their surfaces were modified with oxygen plasma to increase cell adhesion. The designed conduits were investigated by cell culture analyses with Schwann cells (SCs). The conduits were implanted into a 30 mm gap in sciatic nerves of rats. Four months after surgery, the regenerated nerves were monitored and evaluated by macroscopic assessments and histology and behavioral analyses. Results of cellular analyses showed suitable properties of designed conduit for nerve regeneration. The results demonstrated that in the polymeric graft with SCs, the rat sciatic nerve trunk had been reconstructed with restoration of nerve continuity and formatted nerve fibers with myelination. Histological results demonstrated the presence of Schwann and glial cells in regenerated nerves. Functional recovery such as walking, swimming, and recovery of nociceptive function was illustrated for all the grafts especially conduits with SCs. This study proves the feasibility of the artificial nerve graft filled with SCs for peripheral nerve regeneration by bridging a longer defect in an animal model. PMID:24399063

  13. In Vivo Confocal Microscopic Observation of Lamellar Corneal Transplantation in the Rabbit Using Xenogenic Acellular Corneal Scaffolds as a Substitute

    PubMed Central

    Feng, Yun; Wang, Wei

    2015-01-01

    Background: The limiting factor to corneal transplantation is the availability of donors. Research has suggested that xenogenic acellular corneal scaffolds (XACS) may be a possible alternative to transplantation. This study aimed to investigate the viability of performing lamellar corneal transplantation (LCT) in rabbits using canine XACS. Methods: Fresh dog corneas were decellularized by serial digestion, and LCT was performed on rabbit eyes using xenogeneic decellularized corneal matrix. Cellular and morphological changes were observed by slit-lamp, light, and scanning electron microscopy at 7, 30 and 90 days postoperatively. Immunocytochemical staining for specific markers such as keratin 3, vimentin and MUC5AC, was used to identify cells in the graft. Results: Decellularized xenogenic corneal matrix remained transparent for about 1-month after LCT. The recipient cells were able to survive and proliferate into the grafts. Three months after transplantation, grafts had merged with host tissue, and graft epithelialization and vascularization had occurred. Corneal nerve fibers were able to grow into the graft in rabbits transplanted with XACS. Conclusions: Xenogenic acellular corneal scaffolds can maintain the transparency of corneal grafts about 1-month and permit growth of cells and nerve fibers, and is, therefore, a potential substitute or carrier for a replacement cornea. PMID:25836615

  14. Sensory nerve function and auto-mutilation after reconstruction of various gap lengths with nerve guides and autologous nerve grafts.

    PubMed

    den Dunnen, W F; Meek, M F

    2001-05-01

    The aim of this study was to evaluate sensory nerve recovery and auto-mutilation after reconstruction of various lengths of nerve gaps in the sciatic nerve of the rat, using different techniques. Group 4, in which the longest nerve gap (15 mm) was reconstructed with a thin-walled p(DL-lactide-gamma-caprolactone) nerve guide filled with modified denatured muscle tissue, showed the best results in the electro-stimulation tests and signs of severe auto-mutilation were not observed. Even in the control group, in which a 10 mm nerve gap was left open, in two of the five rats improvement of the sensory nerve function was observed, which was caused by re-innervation of the sciatic nerve and not by expansion of the neighboring saphenous nerve. It is hypothesized that a better quality of nerve reconstruction/guidance channel/support results in faster regeneration and hence re-innervation, thereby, preventing auto-mutilation. A thin red glabrous skin, anhydrosis (dryness of the skin), short nails and edema were interpreted as signs of autonomic dysfunction. PMID:11352096

  15. A double transgenic mouse used to track migrating Schwann cells and regenerating axons following engraftment of injured nerves

    PubMed Central

    Hayashi, Ayato; Koob, Jason W; Liu, Daniel Z; Tong, Alice Y; Hunter, Daniel A.; Parsadanian, Alexander; Mackinnon, Susan E.; Myckatyn, Terence M.

    2007-01-01

    We propose that double transgenic thy1-CFP(23)/S100-GFP mice whose Schwann cells constitutively express green fluorescent protein (GFP) and axons express cyan fluorescent protein (CFP) can be used to serially evaluate the temporal relationship between nerve regeneration and Schwann cell migration through acellular nerve grafts. Thy1-CFP(23)/S100-GFP and S100-GFP mice received non-fluorescing cold preserved nerve allografts from immunologically disparate donors. In vivo fluorescent imaging of these grafts was then performed at multiple points. The transected sciatic nerve was reconstructed with a 1 cm nerve allograft harvested from a Balb-C mouse and acellularized via 7 weeks of cold preservation prior to transplantation. The presence of regenerated axons and migrating Schwann cells was confirmed with confocal and electron microscopy on fixed tissue. Schwann cells migrated into the acellular graft (163 ± 15 intensity units) from both proximal and distal stumps, and bridged the whole graft within 10 days (388 ± 107 intensity units in the central 4-6 mm segment). Nerve regeneration lagged behind Schwann cell migration with 5 or 6 axons imaged traversing the proximal 4 mm of the graft under confocal microcopy within 10 days, and up to 21 labeled axons crossing the distal coaptation site by 15 days. Corroborative electron and light microscopy 5 mm into the graft demonstrated relatively narrow diameter myelinated (431±31) and unmyelinated (64±9) axons by 28 but not 10 days. Live imaging of the double-transgenic thy1-CFP(23)/S100-GFP murine line enabled serial assessment of Schwann cell-axonal relationships in traumatic nerve injuries reconstructed with acellular nerve allografts. PMID:17628544

  16. Selectivity of distal reinnervation of regenerating mixed motor and sensory nerve fibres across muscle grafts in rats.

    PubMed

    Rath, S; Green, C J

    1991-04-01

    This study investigated target specificity during axonal regeneration of a mixed motor and sensory nerve towards respective targets. The femoral nerves in rats were divided and allowed to grow across a 6 mm gap interposed with frozen and thawed muscle grafts towards their distal motor and sensory nerve stumps. Fourteen weeks later the number of motoneurons projecting axons into the motor and sensory branches were determined by retrograde axonal tracing using horse-radish peroxidase. There were significantly higher numbers of motoneurons (p = 0.0034) projecting into the motor nerve than the sensory nerve. Efferent axons of a mixed nerve selectivity grew into motor branches when allowed to regenerate across a 6 mm gap interposed with muscle grafts. It is possible that a deliberately created 'structured gap' during repair of mixed nerves could improve axonal matching by allowing expression of neurotropism. PMID:2025759

  17. Electrical Nerve Stimulation Enhances Perilesional Branching after Nerve Grafting but Fails to Increase Regeneration Speed in a Murine Model.

    PubMed

    Witzel, Christian; Brushart, Thomas M; Koulaxouzidis, Georgios; Infanger, Manfred

    2016-07-01

    Background Electrical stimulation immediately following nerve lesion helps regenerating axons cross the subsequently grafted nerve repair site. However, the results and the mechanisms remain open to debate. Some findings show that stimulation after crush injury increases axonal crossing of the repair site without affecting regeneration speed. Others show that stimulation after transection and fibrin glue repair doubles regeneration distance. Methods Using a sciatic-nerve-transection-graft in vivo model, we investigated the morphological behavior of regenerating axons around the repair site after unilateral nerve stimulation (20 Hz, 1 hour). With mice expressing axonal fluorescent proteins (thy1-YFP), we were able to calculate the following at 5 and 7 days: percentage of regenerating axons and arborizing axons, branches per axon, and regeneration distance and speed. Results Brief stimulation significantly increases the percentage of regenerating axons (5 days: 35.5 vs. 27.3% nonstimulated, p < 0.05; 7 days: 43.3 vs. 33.9% nonstimulated, p < 0.05), mainly by increasing arborizing axons (5 days: 49.3 [4.4] vs. 33.9 [4.1]% [p < 0.001]; 7 days: 42.2 [5.6] vs. 33.2 [3.1]% [p < 0.001]). Neither branches per arborizing axon nor regeneration speed were affected. Conclusion Our morphological data analysis revealed that electrical stimulation in this model increases axonal crossing of the repair site and promotes homogeneous perilesional branching, but does not affect regeneration speed. PMID:26975563

  18. Primary repair of crush nerve injuries by means of biological tubulization with muscle-vein-combined grafts.

    PubMed

    Tos, Pierluigi; Battiston, Bruno; Ciclamini, Davide; Geuna, Stefano; Artiaco, Stefano

    2012-07-01

    Despite extensive research and surgical innovation, the treatment of peripheral nerve injuries remains a complex issue, particularly in nonsharp lesions. The aim of this study was to assess the clinical outcome in a group of 16 patients who underwent, in emergency, a primary repair for crush injury of sensory and mixed nerves of the upper limb with biological tubulization, namely, the muscle-vein-combined graft. The segments involved were sensory digital nerves in eight cases and mixed nerves in another eight cases (four median nerves and four ulnar nerves). The length of nerve defect ranged from 0.5 to 4 cm (mean 1.9 cm). Fifteen of 16 patients showed some degree of functional recovery. Six patients showed diminished light touch (3.61), six had protective sensation (4.31), and three showed loss of protective sensation (4.56) using Semmes-Weinstein monofilament test. All the patients who underwent digital nerve repair had favorable results graded as S4 in one case, S3+ in six cases, and S3 in one case. With respect to mixed nerve repair, we observed two S4, two S3+, two S3, one S2, and one S0 sensory recovery. Less favorable results were observed for motor function with three M4, one M3, two M2, and two M0 recoveries. Altogether, the results of this retrospective study demonstrates that tubulization nerve repair in emergency, in case of short nerve gaps, may restore the continuity of the nerve avoiding secondary nerve grafting. This technique preserves donor nerve and, in case of failure, does not preclude a delayed repair with a nerve graft. PMID:22422438

  19. An inside-out vein graft filled with platelet-rich plasma for repair of a short sciatic nerve defect in rats.

    PubMed

    Kim, Ji Yeong; Jeon, Woo Joo; Kim, Dong Hwee; Rhyu, Im Joo; Kim, Young Hwan; Youn, Inchan; Park, Jong Woong

    2014-07-15

    Platelet-rich plasma containing various growth factors can promote nerve regeneration. An inside-out vein graft can substitute nerve autograft to repair short nerve defects. It is hypothesized that an inside-out vein graft filled with platelet-rich plasma shows better effects in the repair of short sciatic nerve defects. In this study, an inside-out vein autograft filled with platelet-rich plasma was used to bridge a 10 mm-long sciatic nerve defect in rats. The sciatic nerve function of rats with an inside-out vein autograft filled with platelet-rich plasma was better improved than that of rats with a simple inside-out vein autograft. At 6 and 8 weeks, the sciatic nerve function of rats with an inside-out vein autograft filled with platelet-rich plasma was better than that of rats undergoing nerve autografting. Compared with the sciatic nerve repaired with a simple inside-out vein autograft, the number of myelinated axons was higher, axon diameter and myelin sheath were greater in the sciatic nerve repaired with an inside-out vein autograft filled with platelet-rich plasma and they were similar to those in the sciatic nerve repaired with nerve autograft. These findings suggest that an inside-out vein graft filled with platelet-rich plasma can substitute nerve autograft to repair short sciatic nerve defects. PMID:25221591

  20. Data from acellular human heart matrix.

    PubMed

    Sánchez, Pedro L; Fernández-Santos, M Eugenia; Espinosa, M Angeles; González-Nicolas, M Angeles; Acebes, Judith R; Costanza, Salvatore; Moscoso, Isabel; Rodríguez, Hugo; García, Julio; Romero, Jesús; Kren, Stefan M; Bermejo, Javier; Yotti, Raquel; Del Villar, Candelas Pérez; Sanz-Ruiz, Ricardo; Elizaga, Jaime; Taylor, Doris A; Fernández-Avilés, Francisco

    2016-09-01

    Perfusion decellularization of cadaveric hearts removes cells and generates a cell-free extracellular matrix scaffold containing acellular vascular conduits, which are theoretically sufficient to perfuse and support tissue-engineered heart constructs. This article contains additional data of our experience decellularizing and testing structural integrity and composition of a large series of human hearts, "Acellular human heart matrix: a critical step toward whole heat grafts" (Sanchez et al., 2015) [1]. Here we provide the information about the heart decellularization technique, the valve competence evaluation of the decellularized scaffolds, the integrity evaluation of epicardial and myocardial coronary circulation, the pressure volume measurements, the primers used to assess cardiac muscle gene expression and, the characteristics of donors, donor hearts, scaffolds and perfusion decellularization process. PMID:27331090

  1. Sciatic nerve regeneration induced by transplantation of in vitro bone marrow stromal cells into an inside-out artery graft in rat.

    PubMed

    Mohammadi, Rahim; Vahabzadeh, Behnam; Amini, Keyvan

    2014-10-01

    Traumatic injury to peripheral nerves results in considerable motor and sensory disability. Several research groups have tried to improve the regeneration of traumatized nerves by invention of favorable microsurgery. Effect of undifferentiated bone marrow stromal cells (BMSCs) combined with artery graft on peripheral nerve regeneration was studied using a rat sciatic nerve regeneration model. A 10-mm sciatic nerve defect was bridged using an artery graft (IOAG) filled with undifferentiated BMSCs (2 × 10(7) cells/mL). In control group, the graft was filled with phosphated buffer saline alone. The regenerated fibers were studied 4, 8 and 12 weeks after surgery. Assessment of nerve regeneration was based on behavioral, functional (Walking Track Analysis), electrophysiological, histomorphometric and immuohistochemical (Schwann cell detection by S-100 expression) criteria. The behavioral, functional and electrophysiological studies confirmed significant recovery of regenerated axons in IOAG/BMSC group (P < 0.05). Quantitative morphometric analyses of regenerated fibers showed the number and diameter of myelinated fibers in IOAG/BMSC group were significantly higher than in the control group (P < 0.05). This demonstrates the potential of using undifferentiated BMSCs combined with artery graft in peripheral nerve regeneration without limitations of donor-site morbidity associated with isolation of Schwann cells. It is also cost saving due to reduction in interval from tissue collection until cell injection, simplicity of laboratory procedures compared to differentiated BMSCs and may have clinical implications for the surgical management of patients after facial nerve transection. PMID:24942097

  2. Approaches to Peripheral Nerve Repair: Generations of Biomaterial Conduits Yielding to Replacing Autologous Nerve Grafts in Craniomaxillofacial Surgery.

    PubMed

    Gaudin, Robert; Knipfer, Christian; Henningsen, Anders; Smeets, Ralf; Heiland, Max; 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

  3. 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

  4. Dose-dependent variations in blood flow evaluation of canine nerve, nerve graft, tendon, and ligament tissue by the radiolabeled-microsphere technique

    SciTech Connect

    Riggi, K.; Wood, M.B.; Ilstrup, D.M. )

    1990-11-01

    This study evaluates the dose-dependent accuracy of the radionuclide-labeled microsphere technique for blood flow evaluation in nerve, tendon, and ligament. In eight dogs, blood flows were determined for nerve, nerve graft, tendon, and ligament tissue by simultaneous injection of high- and low-dose microspheres with different radiolabels. The results demonstrated no significant differences in blood flow as measured from the small number of microspheres (less than 400) and the high number (more than 400) for nerve and tendon tissue. For nerve tissue, microsphere counts of 50 to 100, 100 to 200, 200 to 300, and more than 300 produced mean percentage errors of 12.74% (n = 5, SEM = 4.52), 5.45% (n = 13, SEM = 1.22), 10.22% (n = 6, SEM = 4.37), and 17.08% (n = 12, SEM = 3.30), respectively. For tendon tissue, the same microsphere subdivisions had mean percentage errors of 7.47% (n = 4, SEM = 2.66), 3.63% (n = 6, SEM = 1.34), 15.54% (n = 4, SEM = 4.43), and 12.91% (n = 1), respectively. For ligament tissue, percentage errors were consistently higher; microsphere counts of 30 to 100, 100 to 200, and 200 to 300 produced mean errors of 20.14% (n = 4, SEM = 6.38), 18.66% (n = 4, SEM = 6.24), and 25.78% (n = 2, SEM = 1.97), respectively. Although there was no direct relationship between percentage error and number of microspheres retrieved, we suggest that microsphere counts in the range of 100 to 200 should be considered acceptable for nerve and tendon in the canine. Ligament tissue seems to be less well suited to the microsphere technique; however, further study is warranted.

  5. Isolated mucosal fenestration with localized gingival recession: Closure with an acellular dermal graft. A rare case report with two years' follow-up.

    PubMed

    Balasubramanian, SaravanaKarthikeyan; Singh, Vishal; Bhat, G Subraya; Acharya, Shashi Rashmi; Nidambur Ballal, Vasudev; Saraswathi, Vidya; Vinayachanan, Divya

    2016-01-01

    Mucosal fenestrations are rarely encountered in clinical practice, and as such their management is not often reported. Their treatment might be further complicated due to a communication with the oral environment, making them more susceptible to accumulation of debris, plaque, and calculus, thereby reducing the probability of mucosal renewal. The aim of the present case report is to highlight one such rare clinical scenario and its apt and effective management. Surgical management of an uncommon presentation of concomitant gingival recession with an isolated mucosal fenestration in an atypical location, with an allograft matrix is presented here with 2 years' follow-up. A review of the literature reveals no previous application of AlloDerm graft for the management of a similar situation. PMID:26824083

  6. A novel artificial nerve graft for repairing long-distance sciatic nerve defects: a self-assembling peptide nanofiber scaffold-containing poly(lactic-co-glycolic acid) conduit

    PubMed Central

    Wang, Xianghai; Pan, Mengjie; Wen, Jinkun; Tang, Yinjuan; Hamilton, Audra D.; Li, Yuanyuan; Qian, Changhui; Liu, Zhongying; Wu, Wutian; Guo, Jiasong

    2014-01-01

    In this study, we developed a novel artificial nerve graft termed self-assembling peptide nanofiber scaffold (SAPNS)-containing poly(lactic-co-glycolic acid) (PLGA) conduit (SPC) and used it to bridge a 10-mm-long sciatic nerve defect in the rat. Retrograde tracing, behavioral testing and histomorphometric analyses showed that compared with the empty PLGA conduit implantation group, the SPC implantation group had a larger number of growing and extending axons, a markedly increased diameter of regenerated axons and a greater thickness of the myelin sheath in the conduit. Furthermore, there was an increase in the size of the neuromuscular junction and myofiber diameter in the target muscle. These findings suggest that the novel artificial SPC nerve graft can promote axonal regeneration and remyelination in the transected peripheral nerve and can be used for repairing peripheral nerve injury. PMID:25657734

  7. A novel artificial nerve graft for repairing long-distance sciatic nerve defects: a self-assembling peptide nanofiber scaffold-containing poly(lactic-co-glycolic acid) conduit.

    PubMed

    Wang, Xianghai; Pan, Mengjie; Wen, Jinkun; Tang, Yinjuan; Hamilton, Audra D; Li, Yuanyuan; Qian, Changhui; Liu, Zhongying; Wu, Wutian; Guo, Jiasong

    2014-12-15

    In this study, we developed a novel artificial nerve graft termed self-assembling peptide nanofiber scaffold (SAPNS)-containing poly(lactic-co-glycolic acid) (PLGA) conduit (SPC) and used it to bridge a 10-mm-long sciatic nerve defect in the rat. Retrograde tracing, behavioral testing and histomorphometric analyses showed that compared with the empty PLGA conduit implantation group, the SPC implantation group had a larger number of growing and extending axons, a markedly increased diameter of regenerated axons and a greater thickness of the myelin sheath in the conduit. Furthermore, there was an increase in the size of the neuromuscular junction and myofiber diameter in the target muscle. These findings suggest that the novel artificial SPC nerve graft can promote axonal regeneration and remyelination in the transected peripheral nerve and can be used for repairing peripheral nerve injury. PMID:25657734

  8. Infection in the Nasal Tip Caused by Acellular Dermal Matrix.

    PubMed

    Lee, Kun Hee

    2015-12-01

    A 19-year-old female patient visited our clinic for rhinoplasty. She complained about her low take-off point, which was apparent in profile view, and wanted slight tip projection. She refused additional cartilage harvesting from ears or ribs but consented to the use of homologous tissue, including acellular dermal matrix, for her dorsum and tip. Septoturbinoplasty was performed, and only a very small amount of septal cartilage could be harvested. It was used as both the columellar strut and the alar rim graft. Nasal dorsum and tip were augmented with acellular dermal matrix. Three months postoperatively, she experienced a few episodes of edema and redness on her nasal tip, followed by pus exudation from the nasal skin. Six months postoperatively, she underwent revision rhinoplasty for removal of inflamed grafts, and onlay tip graft with homologous rib cartilage was performed. Nasal dorsum or tip grafts are an integral part of Asian rhinoplasty. Autogenous tissue is the gold standard for grafting materials. However, the limited availability of autogenous tissue and the preference of patients and surgeons for artificial surgical implants make Asian rhinoplasty challenging. Unavailability of autogenous cartilage and patient refusal of artificial implants led to the use of acellular dermal matrix (ADM) in the nasal dorsum and tip for this case. This is the first report of postoperative complication because of infection rather than absorption after ADM use. PMID:26894006

  9. Combination of fibrin-agarose hydrogels and adipose-derived mesenchymal stem cells for peripheral nerve regeneration

    NASA Astrophysics Data System (ADS)

    Carriel, Víctor; Garrido-Gómez, Juan; Hernández-Cortés, Pedro; Garzón, Ingrid; García-García, Salomé; Sáez-Moreno, José Antonio; Sánchez-Quevedo, María del Carmen; Campos, Antonio; Alaminos, Miguel

    2013-04-01

    Objective. The objective was to study the effectiveness of a commercially available collagen conduit filled with fibrin-agarose hydrogels alone or with fibrin-agarose hydrogels containing autologous adipose-derived mesenchymal stem cells (ADMSCs) in a rat sciatic nerve injury model. Approach. A 10 mm gap was created in the sciatic nerve of 48 rats and repaired using saline-filled collagen conduits or collagen conduits filled with fibrin-agarose hydrogels alone (acellular conduits) or with hydrogels containing ADMSCs (ADMSC conduits). Nerve regeneration was assessed in clinical, electrophysiological and histological studies. Main results. Clinical and electrophysiological outcomes were more favorable with ADMSC conduits than with the acellular or saline conduits, evidencing a significant recovery of sensory and motor functions. Histological analysis showed that ADMSC conduits produce more effective nerve regeneration by Schwann cells, with higher remyelination and properly oriented axonal growth that reached the distal areas of the grafted conduits, and with intensely positive expressions of S100, neurofilament and laminin. Extracellular matrix was also more abundant and better organized around regenerated nerve tissues with ADMSC conduits than those with acellular or saline conduits. Significance. Clinical, electrophysiological and histological improvements obtained with tissue-engineered ADMSC conduits may contribute to enhancing axonal regeneration by Schwann cells.

  10. FUNCTIONAL CONNECTIONS ARE ESTABLISHED BETWEEN GIANT NERVE FIBERS IN GRAFTED EARTHWORMS

    EPA Science Inventory

    Giant fiber interconnections were examined in successful grafts between two posterior portions of earthworms (Eisenia foetida). Electrophysiological and histological results indicated that cell-specific interanimal connections were formed between the medial giant fibers (MGF) in ...

  11. Improvement of hind-limb paralysis following traumatic spinal cord injury in rats by grafting normal human keratinocytes: new cell-therapy strategy for nerve regeneration.

    PubMed

    Inoue, Hajime; Takenaga, Mitsuko; Ohta, Yuki; Tomioka, Miyuki; Watabe, Yu-Ichi; Aihara, Masaki; Kumagai, Norio

    2011-12-01

    Somatic (adult) stem cells are thought to have pluripotency, just as do embryotic stem (ES) cells. We investigated the possibility that grafted epithelial keratinocytes could induce spinal cord regeneration in an animal model of spinal cord injury (SCI). Normal human keratinocytes were cultured by the routine technique, and normal human dermal fibroblasts were cultured by a similar method as a control group. SCI model was prepared by dropping a 10-g weight onto the exposed spinal cord of rats from a height of 25 mm, and 8 days later, the cultured cells were grafted into the injury site. Motor function was significantly improved in the cultured-keratinocyte-grafted group compared with that in the fibroblast-grafted group. After functional observation, human nestin- and nuclei-positive cells were found at the grafted spinal cord. Grafted cultured keratinocytes induced in vitro morphological changes in the neural induction medium. These results indicated one possibility that some of the grafted cultured keratinocytes survived and could have contributed to neural regeneration. On the other hand, it should be noted that the grafted cultured keratinocytes secreted a large amount of enzymes and/or growth factors. Therefore, another possibility is that the grafted-keratinocyte-derived factors could induce survived cell growth and endogenous neural differentiation of spinal-nerve-derived stem cells surrounding the injured spinal cord, leading to functional recovery. Epithelial stem cell therapy may be applied clinically in the near future to treat SCI. PMID:21842261

  12. Uncultured undifferentiated adipose-derived nucleated cell fractions combined with inside-out artery graft accelerate sciatic nerve regeneration and functional recovery.

    PubMed

    Mohammadi, R; Asadollahi, A; Amini, K

    2014-09-01

    Effects of transplantation of adipose-derived nucleated cell fractions (ADNCs) on sciatic nerve regeneration were studied. A 10-mm sciatic nerve defect was bridged using artery graft filled with ADNCs. In control group, artery graft was filled with saline alone. Regenerated nerve fibres were studied for 12 weeks. In sham-operated group, sciatic nerve was only exposed and manipulated. Behavioural and functional studies confirmed faster recovery of regenerated axons in ADNCs transplanted animals than in control group (P<0.05). At the end of study period, animals in ADNCs transplanted group achieved a sciatic functional index (SFI) value of -31.6 ± -3.14, whereas in control group a value of -42.5 ± -3.7 was found. Gastrocnemius muscle mass in ADNCs transplanted animals was found to be significantly higher than that in control group (P=0.001). Morphometric indices of regenerated fibres showed the number and diameter of myelinated fibres to be significantly higher in ADNCs transplanted animals than in control group (P=0.001). On immunohistochemistry, there was more positive staining of S100 in the ADNCs transplanted animals than in control group. ADNCs transplantation into an artery graft could be considered a readily accessible technique that improves functional recovery of sciatic nerve. PMID:24951175

  13. A Cell Line Producing Recombinant Nerve Growth Factor Evokes Growth Responses in Intrinsic and Grafted Central Cholinergic Neurons

    NASA Astrophysics Data System (ADS)

    Ernfors, Patrik; Ebendal, Ted; Olson, Lars; Mouton, Peter; Stromberg, Ingrid; Persson, Hakan

    1989-06-01

    The rat β nerve growth factor (NGF) gene was inserted into a mammalian expression vector and cotransfected with a plasmid conferring resistance to neomycin into mouse 3T3 fibroblasts. From this transfection a stable cell line was selected that contains several hundred copies of the rat NGF gene and produces excess levels of recombinant NGF. Such genetically modified cells were implanted into the rat brain as a probe for in vivo effects of NGF on central nervous system neurons. In a model of the cortical cholinergic deficits in Alzheimer disease, we demonstrate a marked increase in the survival of, and fiber outgrowth from, grafts of fetal basal forebrain cholinergic neurons, as well as stimulation of fiber formation by intact adult intrinsic cholinergic circuits in the cerebral cortex. Adult cholinergic interneurons in intact striatum also sprout vigorously toward implanted fibroblasts. Our results suggest that this model has implications for future treatment of neurodegenerative diseases.

  14. Nerve regeneration and elastin formation within poly(glycerol sebacate)-based synthetic arterial grafts one-year post-implantation in a rat model

    PubMed Central

    Allen, Robert A.; Wu, Wei; Yao, Mingyi; Dutta, Debaditya; Duan, Xinjie; Bachman, Timothy N.; Champion, Hunter C.; Stolz, Donna B.; Robertson, Anne M.; Kim, Kang; Isenberg, Jeffrey S.; Wang, Yadong

    2013-01-01

    The objective of this study was to evaluate the long term performance of cell-free vascular grafts made from a fast-degrading elastic polymer. We fabricated small arterial grafts from microporous tubes of poly(glycerol sebacate) (PGS) reinforced with polycaprolactone (PCL) nanofibers on the outer surface. Grafts were interpositioned in rat abdominal aortas and characterized at 1 year post-implant. Grafts remodeled into “neoarteries” (regenerated arteries) with similar gross appearance to native rat aortas. Neoarteries mimic arterial tissue architecture with a confluent endothelium and media and adventita-like layers. Patent vessels (80%) showed no significant stenosis, dilation, or calcification. Neoarteries contain nerves and have the same amount of mature elastin as native arteries. Despite some differences in matrix organization, regenerated arteries had similar dynamic mechanical compliance to native arteries in vivo. Neoarteries responded to vasomotor agents, albeit with different magnitude than native aortas. These data suggest that an elastic vascular graft that resorbs quickly has potential to improve the performance of vascular grafts used in small arteries. This design may also promote constructive remodeling in other soft tissues. PMID:24119457

  15. Bridging Grafts and Transient Nerve Growth Factor Infusions Promote Long-Term Central Nervous System Neuronal Rescue and Partial Functional Recovery

    NASA Astrophysics Data System (ADS)

    Tuszynski, Mark H.; Gage, Fred H.

    1995-05-01

    Grafts of favorable axonal growth substrates were combined with transient nerve growth factor (NGF) infusions to promote morphological and functional recovery in the adult rat brain after lesions of the septohippocampal projection. Long-term septal cholinergic neuronal rescue and partial hippocampal reinnervation were achieved, resulting in partial functional recovery on a simple task assessing habituation but not on a more complex task assessing spatial reference memory. Control animals that received transient NGF infusions without axonal-growth-promoting grafts lacked behavioral recovery but also showed long-term septal neuronal rescue. These findings indicate that (i) partial recovery from central nervous system injury can be induced by both preventing host neuronal loss and promoting host axonal regrowth and (ii) long-term neuronal loss can be prevented with transient NGF infusions.

  16. Use of an Acellular Regenerative Tissue Matrix Over Chronic Wounds

    PubMed Central

    Stacey, D. Heath

    2013-01-01

    Objectives: Bioengineered skin grafts, including acellular dermal matrices, may be effective in treating lower extremity and trunk wounds that are not responsive to traditional wound management. Acellular dermal wound matrix is derived from human acellular dermal wound matrix (HADWM) tissue and provides a scaffold that supports cellular repopulation and revascularization. The major structural components of the dermis are retained during processing, and a single application has been shown to help achieve wound closure. Methods: This patient case series examined the use of HADWM on lower extremity and trunk wounds in 11 patients (6 male and 5 female) with a mean age of 55 years (range: 31–83 years). Wounds were debrided 1 to 2 times, followed by placement of HADWM (range: 4–330 cm2) on wounds that varied from the dorsal surface of the foot, lower abdomen, and lower extremity to the Achilles flap. A nonadherent layer in conjunction with bacitracin was placed over HADWM. Negative pressure wound therapy (NPWT) was placed over the HADWM and initiated continuously at −125 mm Hg for 1 to 2 weeks. After the application of NPWT, HADWM was covered with various gauze dressings using mineral oil. Results: All patients completed their treatment successfully, and follow-up ranged from 1 week to 6 months. One patient experienced an infection, which resulted in partial graft loss that required replacement with HADWM and NPWT. No additional complications occurred in the other patients. Conclusions: This patient case series demonstrated successful use of HADWM and NPWT, which further supports published studies documenting HADWM success in chronic wounds. PMID:24324850

  17. Deep Anterior Lamellar Keratoplasty Using Irradiated Acellular Cornea with Amniotic Membrane Transplantation for Intractable Ocular Surface Diseases

    PubMed Central

    Wee, Sung Wook; Choi, Sang Uk

    2015-01-01

    Purpose To report the clinical outcomes of deep anterior lamellar keratoplasty (DALK) when sterile gamma-irradiated acellular corneal tissues (VisionGraft) are used in combination with amniotic membrane transplantation (AMT) for intractable ocular surface diseases. Methods The medical records of fifteen patients who had DALK with AMT were retrospectively reviewed. Indications for surgery included ocular burn, bacterial keratitis, herpes simplex virus keratitis, corneal opacity with Stevens-Johnson syndrome, Mooren's ulcer, idiopathic myxoid degeneration of corneal stroma, and recurrent band keratopathy. DALK was performed using partial-thickness acellular corneal tissue and a temporary amniotic membrane patch was added at the end of the operation. Results All cases that underwent DALK with AMT became epithelialized within 2 postoperative weeks. Twelve patients showed favorable outcomes without graft rejection, corneal opacification, or neovascularization. The other three grafts developed corneal opacification and neovascularization, and required additional penetrating keratoplasty (PK). Unlike the results of previous PKs, there were no graft rejections and the graft clarity was well-maintained in these three cases for at least 8 months after PK. Conclusions DALK using sterile acellular corneal tissues in combination with AMT may be a good therapeutic strategy for treating intractable ocular surface diseases because of lowered immune rejection, fibroblast activation, and facilitation of epithelialization. Furthermore, DALK can help stabilize the ocular surface, prolong graft survival, and may allow better outcomes when combined with subsequent PK. PMID:25829823

  18. A simple model of radial nerve injury in the rhesus monkey to evaluate peripheral nerve repair.

    PubMed

    Wang, Dong; Huang, Xijun; Fu, Guo; Gu, Liqiang; Liu, Xiaolin; Wang, Honggang; Hu, Jun; Yi, Jianhua; Niu, Xiaofeng; Zhu, Qingtang

    2014-05-15

    Current research on bone marrow stem cell transplantation and autologous or xenogenic nerve transplantation for peripheral nerve regeneration has mainly focused on the repair of peripheral nerve defects in rodents. In this study, we established a standardized experimental model of radial nerve defects in primates and evaluated the effect of repair on peripheral nerve injury. We repaired 2.5-cm lesions in the radial nerve of rhesus monkeys by transplantation of autografts, acellular allografts, or acellular allografts seeded with autologous bone marrow stem cells. Five months after surgery, regenerated nerve tissue was assessed for function, electrophysiology, and histomorphometry. Postoperative functional recovery was evaluated by the wrist-extension test. Compared with the simple autografts, the acellular allografts and allografts seeded with bone marrow stem cells facilitated remarkable recovery of the wrist-extension functions in the rhesus monkeys. This functional improvement was coupled with radial nerve distal axon growth, a higher percentage of neuron survival, increased nerve fiber density and diameter, increased myelin sheath thickness, and increased nerve conduction velocities and peak amplitudes of compound motor action potentials. Furthermore, the quality of nerve regeneration in the bone marrow stem cells-laden allografts group was comparable to that achieved with autografts. The wrist-extension test is a simple behavioral method for objective quantification of peripheral nerve regeneration. PMID:25206757

  19. Biomechanical evaluation of acellular collagen matrix augmented Achilles tendon repair in sheep.

    PubMed

    Song, Lin; Olsen, Raymond E; Spalazzi, Jeffrey P; Davisson, Twana

    2010-01-01

    The rate of rerupture of repaired Achilles tendon in young and athletic populations remains high despite improvement in surgical techniques, suture design, and postsurgical management. Acellular biological matrices can be used to enhance the immediate strength of repaired tendons and to serve as scaffolds for cell in-growth and constructive tissue remodeling. A number of commercially available matrices have been used clinically, albeit with varying degrees of success and failure. The disparity is likely attributable to the different physical and biochemical properties of individual matrices. In this study, we investigated the biomechanical characteristics of 2 different acellular collagen matrices, namely TissueMend and GraftJacket, using a sheep Achilles tendon repair model. Static and cyclic creep, cyclic and linear construct stiffness, maximum load to failure, and displacement at maximum load were determined at time zero. We found that the maximum load to failure, displacement, and ultimate failure mode were similar between tendons augmented with either acellular collagen matrix; however, TissueMend augmentation yielded lower creep and smaller construct elongation than did GraftJacket. The results indicated that the strength of TissueMend-augmented tendons and GraftJacket-augmented tendons was not statistically significantly different, although tendons augmented with TissueMend displayed greater stiffness, which may be clinically advantageous in the restoration of ruptured tendons. PMID:20797586

  20. Acellular ostrich corneal stroma used as scaffold for construction of tissue-engineered cornea

    PubMed Central

    Liu, Xian-Ning; Zhu, Xiu-Ping; Wu, Jie; Wu, Zheng-Jie; Yin, Yong; Xiao, Xiang-Hua; Su, Xin; Kong, Bin; Pan, Shi-Yin; Yang, Hua; Cheng, Yan; An, Na; Mi, Sheng-Li

    2016-01-01

    AIM To assess acellular ostrich corneal matrix used as a scaffold to reconstruct a damaged cornea. METHODS A hypertonic saline solution combined with a digestion method was used to decellularize the ostrich cornea. The microstructure of the acellular corneal matrix was observed by transmission electron microscopy (TEM) and hematoxylin and eosin (H&E) staining. The mechanical properties were detected by a rheometer and a tension machine. The acellular corneal matrix was also transplanted into a rabbit cornea and cytokeratin 3 was used to check the immune phenotype. RESULTS The microstructure and mechanical properties of the ostrich cornea were well preserved after the decellularization process. In vitro, the methyl thiazolyl tetrazolium results revealed that extracts of the acellular ostrich corneas (AOCs) had no inhibitory effects on the proliferation of the corneal epithelial or endothelial cells or on the keratocytes. The rabbit lamellar keratoplasty showed that the transplanted AOCs were transparent and completely incorporated into the host cornea while corneal turbidity and graft dissolution occurred in the acellular porcine cornea (APC) transplantation. The phenotype of the reconstructed cornea was similar to a normal rabbit cornea with a high expression of cytokeratin 3 in the superficial epithelial cell layer. CONCLUSION We first used AOCs as scaffolds to reconstruct damaged corneas. Compared with porcine corneas, the anatomical structures of ostrich corneas are closer to those of human corneas. In accordance with the principle that structure determines function, a xenograft lamellar keratoplasty also confirmed that the AOC transplantation generated a superior outcome compared to that of the APC graft. PMID:27158598

  1. Application of acellular dermis and autograft on burns and scars.

    PubMed

    Ramos Duron, L E; Martínez Pardo, M E; Olivera Zavaleta, V; Silva Diaz, T; Reyes Frías, M L; Luna Zaragoza, D

    1999-01-01

    The cases of two patients with burns treated with dermis allograft and of one patient for lip reconstructive aesthetic filling treated with less than one mm3 of radiosterilised acellular dermis are presented. This paper emphasizes the treatment with radiosterilised dermal grafts with a permanent character so far. Hospitals, therefore, can satisfy the demand for this kind of tissue in the case of disaster and patients with serious injuries. In the cases cited, histocompatibility analysis was not required, thus having the advantage of long-time storage of the radiosterilised dermis used on these patients. Neither inflammatory reaction nor acute phase re-absorption were observed. Moreover, shrink (contract) healing was diminished. After two years, the results are still satisfactory. PMID:10853787

  2. DermACELL: Human Acellular Dermal Matrix Allograft A Case Report.

    PubMed

    Cole, Windy E

    2016-03-01

    Diabetes often causes ulcers on the feet of diabetic patients. A 56-year-old, insulin-dependent, diabetic woman presented to the wound care center with a Wagner grade 3 ulcer of the right heel. She reported a 3-week history of ulceration with moderate drainage and odor and had a history of ulceration and osteomyelitis in the contralateral limb. Rigorous wound care, including hospitalization; surgical incision and drainage; intravenous antibiotic drug therapy; vacuum-assisted therapy; and a new room temperature, sterile, human acellular dermal matrix graft were used to heal the wound, save her limb, and restore her activities of daily living. This case presentation involves alternative treatment of a diabetic foot ulcer with this new acellular dermal matrix, DermACELL. PMID:27031550

  3. Human acellular dermal matrix for repair of abdominal wall defects: review of clinical experience and experimental data.

    PubMed

    Holton, Luther H; Kim, Daniel; Silverman, Ronald P; Rodriguez, Eduardo D; Singh, Navin; Goldberg, Nelson H

    2005-01-01

    The use of prosthetic mesh for the tension-free repair of incisional hernias has been shown to be more effective than primary suture repair. Unfortunately, prosthetic materials can be a suboptimal choice in a variety of clinical scenarios. In general, prosthetic materials should not be implanted into sites with known contamination or infection because they lack an endogenous vascular network and are thus incapable of clearing bacteria. This is of particular relevance to the repair of recurrent hernias, which are often refractory to repair because of indolent bacterial colonization that weakens the site and retards appropriate healing. Although fascia lata grafts and muscle flaps can be employed for tension-free hernia repairs, they carry the potential for significant donor site morbidity. Recently, a growing number of clinicians have used human acellular dermal matrix as a graft material for the tension-free repair of ventral hernias. This material has been shown to become revascularized in both animal and human subjects. Once repopulated with a vascular network, this graft material is theoretically capable of clearing bacteria, a property not found in prosthetic graft materials. Unlike autologous materials such as fascial grafts and muscle flaps, acellular dermal matrix can be used without subjecting the patient to additional morbidity in the form of donor site complications. This article presents a thorough review of the current literature, describing the properties of human acellular dermal matrix and discussing both animal and human studies of its clinical performance. In addition to the review of previously published clinical experiences, we discuss our own preliminary results with the use of acellular dermal matrix for ventral hernia repair in 46 patients. PMID:16218902

  4. Outcomes of allogenic acellular matrix therapy in treatment of diabetic foot wounds: an initial experience.

    PubMed

    Martin, Billy R; Sangalang, Melinda; Wu, Stephanie; Armstrong, David G

    2005-06-01

    The purpose of this study was to evaluate outcomes of persons with UT grade 2A neuropathic diabetic foot wounds treated with an acellular matrix. Data were abstracted for 17 consecutive patients with diabetes--76.5% males, aged 61.5 +/- 8.5 years with a mean glycated haemoglobin of 9.2 +/- 2.2% presenting for care at a large, multidisciplinary wound care centre. All patients received surgical debridement for their diabetic foot wounds and were placed on therapy consisting of a single application of an acellular matrix graft (GraftJacket; Wright Medical Technologies, Arlington, TN, USA) with dressing changes taking place weekly. Outcomes evaluated included time to complete wound closure and proportion of patients achieving wound closure in 20 weeks. Acellular matrix therapy was used as initial therapy and was sutured or stapled in place under a silicone-based non adherent dressing. Therapy was then followed by a moisture-retentive dressing until complete epithelialisation. In total, 82.4% of wounds measuring a mean 4.6 +/- 3.2 cm(2) healed in the 20-week evaluation period. For those that healed in this period, healing took place in a mean 8.9 +/- 2.7 weeks. We conclude that a regimen consisting of moist wound healing using an acellular matrix dressing may be a useful adjunct to appropriate diabetic foot ulcer care for deep, non-infected, non-ischaemic wounds. We await the completion of further trials in this area to confirm or refute this initial assessment. PMID:16722865

  5. High Ulnar Nerve Injuries: Nerve Transfers to Restore Function.

    PubMed

    Patterson, Jennifer Megan M

    2016-05-01

    Peripheral nerve injuries are challenging problems. Nerve transfers are one of many options available to surgeons caring for these patients, although they do not replace tendon transfers, nerve graft, or primary repair in all patients. Distal nerve transfers for the treatment of high ulnar nerve injuries allow for a shorter reinnervation period and improved ulnar intrinsic recovery, which are critical to function of the hand. PMID:27094893

  6. Obstetrical brachial plexus palsy: Can excision of upper trunk neuroma and nerve grafting improve function in babies with adequate elbow flexion at nine months of age?

    PubMed

    Argenta, Anne E; Brooker, Jack; MacIssac, Zoe; Natali, Megan; Greene, Stephanie; Stanger, Meg; Grunwaldt, Lorelei

    2016-05-01

    Accepted indications for exploration in obstetrical brachial plexus palsy (OBPP) vary by center. Most agree that full elbow flexion against gravity at nine months of age implies high chance of spontaneous recovery and thus excludes a baby from surgical intervention. However, there are certain movements of the shoulder and forearm that may not be used frequently by the infant, but are extremely important functionally as they grow. These movements are difficult to assess in a baby and may lead to some clinicians to recommend conservative treatment, when this cohort of infants may in fact benefit substantially from surgery. A retrospective review was conducted on all infants managed surgically at the Brachial Plexus Center of a major children's hospital from 2009 to 2014. Further analysis identified five patients who had near-normal AMS scores for elbow flexion but who had weakness of shoulder abduction, flexion, external rotation, and/or forearm supination. In contrast to standard conservative management, this cohort underwent exploration, C5-6 neuroma excision, and sural nerve grafting. Data analysis was performed on this group to look for overall improvement in function. During an average follow-up period of 29 months, all patients made substantial gains in motor function of the shoulder and forearm, without loss of elbow flexion or extension, or worsening of overall outcome. In select infants with brachial plexus injuries but near-normal AMS scores for elbow flexion, surgical intervention may be indicated to achieve the best functional outcome. PMID:26806089

  7. In vitro assessment of biodurability: acellular systems.

    PubMed Central

    de Meringo, A; Morscheidt, C; Thélohan, S; Tiesler, H

    1994-01-01

    The assessment of biodurability of man-made vitreous fibers is essential to the limitation of health hazards associated with human exposure to environments in which respirable fibers are present. In vitro acellular systems provide effective test methods of measuring fiber solubility provided care is taken to select the most suitable solvent and test conditions for the specific fiber type and dimension. PMID:7882955

  8. Decellularisation and histological characterisation of porcine peripheral nerves.

    PubMed

    Zilic, Leyla; Wilshaw, Stacy-Paul; Haycock, John W

    2016-09-01

    Peripheral nerve injuries affect a large proportion of the global population, often causing significant morbidity and loss of function. Current treatment strategies include the use of implantable nerve guide conduits (NGC's) to direct regenerating axons between the proximal and distal ends of the nerve gap. However, NGC's are limited in their effectiveness at promoting regeneration Current NGCs are not suitable as substrates for supporting either neuronal or Schwann cell growth, as they lack an architecture similar to that of the native extracellular matrix (ECM) of the nerve. The aim of this study was to create an acellular porcine peripheral nerve using a novel decellularisation protocol, in order to eliminate the immunogenic cellular components of the tissue, while preserving the three-dimensional histoarchitecture and ECM components. Porcine peripheral nerve (sciatic branches were decellularised using a low concentration (0.1%; w/v) sodium dodecyl sulphate in conjunction with hypotonic buffers and protease inhibitors, and then sterilised using 0.1% (v/v) peracetic acid. Quantitative and qualitative analysis revealed a ≥95% (w/w) reduction in DNA content as well as preservation of the nerve fascicles and connective tissue. Acellular nerves were shown to have retained key ECM components such as collagen, laminin and fibronectin. Slow strain rate to failure testing demonstrated the biomechanical properties of acellular nerves to be comparable to fresh controls. In conclusion, we report the production of a biocompatible, biomechanically functional acellular scaffold, which may have use in peripheral nerve repair. Biotechnol. Bioeng. 2016;113: 2041-2053. © 2016 The Authors. Biotechnology and Bioengineering published by Wiley Periodicals, Inc. PMID:26926914

  9. Sural nerve defects after nerve biopsy or nerve transfer as a sensory regeneration model for peripheral nerve conduit implantation.

    PubMed

    Radtke, C; Kocsis, J D; Reimers, K; Allmeling, C; Vogt, P M

    2013-09-01

    Nerve repair after injury can be effectively accomplished by direct suture approximation of the proximal and distal segments. This is more successful if coadaptation can be achieved without tension. Currently, the gold standard repair of larger deficits is the transplantation of an autologous sensory sural nerve graft. However, a significant disadvantage of this technique is the inevitable donor morbidity (sensory loss, neuroma and scar formation) after harvesting of the sural nerve. Moreover, limitation of autologous donor nerve length and fixed diameter of the available sural nerve are major drawbacks of current autograft treatment. Another approach that was introduced for nerve repair is the implantation of alloplastic nerve tubes made of, for example, poly-L-lactide. In these, nerve stumps of the transected nerves are surgically bridged using the biosynthetic conduit. A number of experimental studies, primarily in rodents, indicate axonal regeneration and remyelination after implantation of various conduits. However, only limited clinical studies with conduit implantation have been performed in acute peripheral nerve injuries particularly on digital nerves. Clinical transfer of animal studies, which can be carefully calibrated for site and extent of injury, to humans is difficult to interpret due to the intrinsic variability in human nerve injuries. This prevents effective quantification of improvement and induces bias in the study. Therefore, standardization of lesion/repair in human studies is warranted. Here we propose to use sural nerve defects, induced due to nerve graft harvesting or from diagnostic nerve biopsies as a model site to enable standardization of nerve conduit implantation. This would help better with the characterization of the implants and its effectiveness in axonal regeneration and remyelination. Nerve regeneration can be assessed, for example, by recovery of sensation, measured non-invasively by threshold to von Frey filaments and cold

  10. Nerve Transfers for the Restoration of Wrist, Finger, and Thumb Extension After High Radial Nerve Injury.

    PubMed

    Pet, Mitchell A; Lipira, Angelo B; Ko, Jason H

    2016-05-01

    High radial nerve injury is a common pattern of peripheral nerve injury most often associated with orthopedic trauma. Nerve transfers to the wrist and finger extensors, often from the median nerve, offer several advantages when compared to nerve repair or grafting and tendon transfer. In this article, we discuss the forearm anatomy pertinent to performing these nerve transfers and review the literature surrounding nerve transfers for wrist, finger, and thumb extension. A suggested algorithm for management of acute traumatic high radial nerve palsy is offered, and our preferred surgical technique for treatment of high radial nerve palsy is provided. PMID:27094891

  11. Acellular organ scaffolds for tumor tissue engineering

    NASA Astrophysics Data System (ADS)

    Guller, Anna; Trusova, Inna; Petersen, Elena; Shekhter, Anatoly; Kurkov, Alexander; Qian, Yi; Zvyagin, Andrei

    2015-12-01

    Rationale: Tissue engineering (TE) is an emerging alternative approach to create models of human malignant tumors for experimental oncology, personalized medicine and drug discovery studies. Being the bottom-up strategy, TE provides an opportunity to control and explore the role of every component of the model system, including cellular populations, supportive scaffolds and signalling molecules. Objectives: As an initial step to create a new ex vivo TE model of cancer, we optimized protocols to obtain organ-specific acellular matrices and evaluated their potential as TE scaffolds for culture of normal and tumor cells. Methods and results: Effective decellularization of animals' kidneys, ureter, lungs, heart, and liver has been achieved by detergent-based processing. The obtained scaffolds demonstrated biocompatibility and growthsupporting potential in combination with normal (Vero, MDCK) and tumor cell lines (C26, B16). Acellular scaffolds and TE constructs have been characterized and compared with morphological methods. Conclusions: The proposed methodology allows creation of sustainable 3D tumor TE constructs to explore the role of organ-specific cell-matrix interaction in tumorigenesis.

  12. A modular, plasmin-sensitive, clickable poly(ethylene glycol)-heparin-laminin microsphere system for establishing growth factor gradients in nerve guidance conduits.

    PubMed

    Roam, Jacob L; Yan, Ying; Nguyen, Peter K; Kinstlinger, Ian S; Leuchter, Michael K; Hunter, Daniel A; Wood, Matthew D; Elbert, Donald L

    2015-12-01

    Peripheral nerve regeneration is a complex problem that, despite many advancements and innovations, still has sub-optimal outcomes. Compared to biologically derived acellular nerve grafts and autografts, completely synthetic nerve guidance conduits (NGC), which allow for precise engineering of their properties, are promising but still far from optimal. We have developed an almost entirely synthetic NGC that allows control of soluble growth factor delivery kinetics, cell-initiated degradability and cell attachment. We have focused on the spatial patterning of glial-cell derived human neurotrophic factor (GDNF), which promotes motor axon extension. The base scaffolds consisted of heparin-containing poly(ethylene glycol) (PEG) microspheres. The modular microsphere format greatly simplifies the formation of concentration gradients of reversibly bound GDNF. To facilitate axon extension, we engineered the microspheres with tunable plasmin degradability. 'Click' cross-linking chemistries were also added to allow scaffold formation without risk of covalently coupling the growth factor to the scaffold. Cell adhesion was promoted by covalently bound laminin. GDNF that was released from these microspheres was confirmed to retain its activity. Graded scaffolds were formed inside silicone conduits using 3D-printed holders. The fully formed NGC's contained plasmin-degradable PEG/heparin scaffolds that developed linear gradients in reversibly bound GDNF. The NGC's were implanted into rats with severed sciatic nerves to confirm in vivo degradability and lack of a major foreign body response. The NGC's also promoted robust axonal regeneration into the conduit. PMID:26352518

  13. Use of Double Layer of Acellular Dermal Matrix and Modified Tunnel Technique to Treat Multiple Adjacent Gingival Recession Defects.

    PubMed

    Mahn, Douglas H

    2016-09-01

    The goal of connective tissue grafting is to cover exposed root surfaces with gingival tissues that are stable and have a natural appearance. The use of an acellular dermal matrix (ADM) has been shown to be a successful alternative to the palatal connective tissue graft. Use of a double layer of an ADM has been shown to have stable results for 1 year. Tunnel grafting techniques can yield root coverage with a natural appearing soft-tissue architecture. The purpose of this case report is to demonstrate the use of a modified tunnel technique and a double layer of ADM in the treatment of multiple adjacent gingival recession defects. Treated teeth were found to have root coverage and natural soft-tissue contours that were stable at 20 months. PMID:27606567

  14. Skin graft

    MedlinePlus

    Skin transplant; Skin autografting; FTSG; STSG; Split thickness skin graft; Full thickness skin graft ... site. Most people who are having a skin graft have a split-thickness skin graft. This takes ...

  15. Interposition Porcine Acellular Dermal Matrix Xenograft Successful Alternative in Treatment for Massive Rotator Cuff

    PubMed Central

    Neumann, Julie; Zgonis, Miltiadis H.; Reay, Kathleen Dolores; Mayer, Stephanie W.; Boggess, Blake; Toth, Alison P.

    2016-01-01

    Objectives: Despite advances in the surgical techniques of rotator cuff repair (RCR), the management of massive rotator cuff tears in shoulders without glenohumeral arthritis poses a difficult problem for surgeons. Failure of massive rotator cuff repairs range from 20-90% at one to two years postoperatively using arthrography, ultrasound, or magnetic resonance imaging. Additionally, there are inconsistent outcomes reported with debridement alone of massive rotator cuff tears as well as limitations seen with other current methods of operative intervention including arthroplasty and tendon transfers. The purpose of this prospective, comparative study was to determine if the repair of massive rotator cuff tears using an interposition porcine acellular dermal matrix xenograft improves subjective function, pain, range of motion, and strength at greater than two years follow-up. To our knowledge, this is the largest prospective series reporting outcomes of using porcine acellular dermal matrix xenograft as an interposition graft. Methods: Thirty-seven patients (37 shoulders) with an average age of 66 years (range 51-80 years) were prospectively followed for 33 months (range 23-48) following massive RCR using porcine acellular dermal matrix interposition xenograft. Subjective outcomes were measured using the Visual Analog Scale (VAS) pain score (0-10, 0 = no pain), Modified American Shoulder and Elbow Score (M-ASES), and Short-Form12 (SF-12) scores. Preoperative and postoperative objective outcome measures included active range of motion and supraspinatus and infraspinatus manual muscle strength. Postoperative outcome measures included quantitative muscle strength using a dynamometer and static and dynamic ultrasonography to assess the integrity of the repair. Results: Average VAS pain score decreased from 4.5 to 1.1 (P<0.001). Average postoperative M-ASES was 89.23. Average postoperative SF-12 was 52.6. Mean forward flexion, external and internal rotation significantly

  16. A Silk Fibroin/Collagen Nerve Scaffold Seeded with a Co-Culture of Schwann Cells and Adipose-Derived Stem Cells for Sciatic Nerve Regeneration

    PubMed Central

    Li, Ruixin; Li, Dong; Feng, Shiqing

    2016-01-01

    As a promising alternative to autologous nerve grafts, tissue-engineered nerve grafts have been extensively studied as a way to bridge peripheral nerve defects and guide nerve regeneration. The main difference between autogenous nerve grafts and tissue-engineered nerve grafts is the regenerative microenvironment formed by the grafts. If an appropriate regenerative microenvironment is provided, the repair of a peripheral nerve is feasible. In this study, to mimic the body’s natural regenerative microenvironment closely, we co-cultured Schwann cells (SCs) and adipose-derived stem cells (ADSCs) as seed cells and introduced them into a silk fibroin (SF)/collagen scaffold to construct a tissue-engineered nerve conduit (TENC). Twelve weeks after the three different grafts (plain SF/collagen scaffold, TENC, and autograft) were transplanted to bridge 1-cm long sciatic nerve defects in rats, a series of electrophysiological examinations and morphological analyses were performed to evaluate the effect of the tissue-engineered nerve grafts on peripheral nerve regeneration. The regenerative outcomes showed that the effect of treatment with TENCs was similar to that with autologous nerve grafts but superior to that with plain SF/collagen scaffolds. Meanwhile, no experimental animals had inflammation around the grafts. Based on this evidence, our findings suggest that the TENC we developed could improve the regenerative microenvironment and accelerate nerve regeneration compared to plain SF/collagen and may serve as a promising strategy for peripheral nerve repair. PMID:26799619

  17. The use of acellular dermal matrix as a scaffold for periosteum replacement.

    PubMed

    Beniker, Dan; McQuillan, David; Livesey, Stephen; Urban, Robert M; Turner, Thomas M; Blum, Barbara; Hughes, Kim; Haggard, Warren O

    2003-05-01

    Three preclinical models were used to evaluate GraftJacket Acellular Periosteum Replacement Scaffold (Wright Medical Technology, Inc, Arlington, Tenn). The studies assessed the ability of the acellular dermal matrix to repopulate with cells, revascularize, provide a protected environment for bone defect restoration, and minimize fibrous tissue infiltration. An athymic nude rat muscle implantation study demonstrated a steady increase in cellular repopulation through days 2-21. The formation of blood vessels occurred between days 7-14 in this study. Results from a porcine femoral drill hole study indicated that the scaffold material was intact and adherent to surrounding bone and allowed cellular repopulation and vascular infiltration at a 5-week time period. A preliminary porcine segmental bone defect model at a 6-week time period demonstrated the ability of the scaffold material to protect the bone defect site as revealed by new bone formation within the margins of the defect and adjacent to the scaffold. The segmental model also indicated minimal to no soft tissue invasion into the defect site. The combined studies provided preliminary evidence that the dermal membrane material may be used as a scaffold for periosteum regeneration by allowing for cellular repopulation, revascularization, and bone defect restoration. PMID:12755232

  18. Creation and implantation of acellular rat renal ECM-based scaffolds

    PubMed Central

    Peloso, Andrea; Ferrario, Jacopo; Maiga, Benedetta; Benzoni, Ilaria; Bianco, Carolina; Citro, Antonio; Currao, Manuela; Malara, Alessandro; Gaspari, Annalisa; Balduini, Alessandra; Abelli, Massimo; Piemonti, Lorenzo; Dionigi, Paolo; Orlando, Giuseppe; Maestri, Marcello

    2015-01-01

    Abstract Kidney transplantation is the only potentially curative treatment for patient facing end-stage renal disease, and it is now routinely used. Its use is mainly limited by the supply of transplantable donor organs, which far exceeds the demand. Regenerative medicine and tissue engineering offer promising means for overcoming this shortage. In the present study, we developed and validated a protocol for producing acellular rat renal scaffolds. Left kidneys were removed from 26 male Lewis rats (weights: 250–350 g) and decellularized by means of aortic anterograde perfusion with ionic and anionic detergents (Triton X-100 1% and SDS 1%, respectively). 19 scaffolds thus obtained (and contralateral native kidneys as controls) were deeply characterized in order to evaluate the decellularization quality, the preservation of extracellular matrix components and resultant micro-angioarchitecture structure. The other 7 were transplanted into 7 recipient rats that had undergone unilateral nephrectomy. Recipients were sacrificed on post-transplantation day 7 and the scaffolds subjected to histologic studies. The dual-detergent protocol showed, with only 5 h of perfusion per organ, to obtain thoroughly decellularized renal scaffolds consisting almost exclusively of extracellular matrix. Finally the macro- and the microarchitecture of the renal parenchyma were well preserved, and the grafts were implanted with ease. Seven days after transplant, the scaffolds were morphologically intact although all vascular structures were obstructed with thrombi. Production and implantation of acellular rat renal scaffolds is a suitable platform for further studies on regenerative medicine and tissue engineering. PMID:26186418

  19. Management of failed and infected first metatarsophalangeal joint implant arthroplasty by reconstruction with an acellular dermal matrix: a case report.

    PubMed

    Khoury, Wissam E; Fahim, Ramy; Sciulli, Jessica M; Ehredt, Duane J

    2012-01-01

    Management of failed first metatarsophalangeal joint implant arthroplasty, especially in the face of infection, is an area of debate without a clear consensus. The purpose of the present report was to explore a new option of reconstructing the joint with an acellular dermal matrix substance in a single case study during a 12-month follow-up period. A staged approach that began with removal of the failed 2-component great toe implant, Koenig(®), excisional debridement of the wound with resection of the necrotic bone (proximal phalanx and distal portion of the first metatarsal bones), and culture-specific antibiosis therapy. The final stage included incorporating the acellular dermal matrix, Graftjacket(®) into the joint in an accordion-type fashion, and reconstruction of the joint capsule. Postoperative radiographs revealed a more rectus joint with some improvement in length. At 6 months postoperatively, magnetic resonance imaging revealed incorporation of the graft material into the joint. Finally, at the 1-year mark, the patient was pain free with satisfactory function at the first metatarsophalangeal joint during gait. This is the first reported case of salvaging failed and infected first metatarsophalangeal joint implant arthroplasty with incorporation of the acellular dermal matrix and provides a new option to consider in the future. PMID:22704789

  20. An anatomical study of porcine peripheral nerve and its potential use in nerve tissue engineering

    PubMed Central

    Zilic, Leyla; Garner, Philippa E; Yu, Tong; Roman, Sabiniano; Haycock, John W; Wilshaw, Stacy-Paul

    2015-01-01

    Current nerve tissue engineering applications are adopting xenogeneic nerve tissue as potential nerve grafts to help aid nerve regeneration. However, there is little literature that describes the exact location, anatomy and physiology of these nerves to highlight their potential as a donor graft. The aim of this study was to identify and characterise the structural and extracellular matrix (ECM) components of porcine peripheral nerves in the hind leg. Methods included the dissection of porcine nerves, localisation, characterisation and quantification of the ECM components and identification of nerve cells. Results showed a noticeable variance between porcine and rat nerve (a commonly studied species) in terms of fascicle number. The study also revealed that when porcine peripheral nerves branch, a decrease in fascicle number and size was evident. Porcine ECM and nerve fascicles were found to be predominately comprised of collagen together with glycosaminoglycans, laminin and fibronectin. Immunolabelling for nerve growth factor receptor p75 also revealed the localisation of Schwann cells around and inside the fascicles. In conclusion, it is shown that porcine peripheral nerves possess a microstructure similar to that found in rat, and is not dissimilar to human. This finding could extend to the suggestion that due to the similarities in anatomy to human nerve, porcine nerves may have utility as a nerve graft providing guidance and support to regenerating axons. PMID:26200940

  1. Improvement of functional recovery of transected peripheral nerve by means of chitosan grafts filled with vitamin E, pyrroloquinoline quinone and their combination.

    PubMed

    Azizi, Asghar; Azizi, Saeed; Heshmatian, Behnam; Amini, Keyvan

    2014-01-01

    Effects of vitamin E and pyrroloquinoline quinone on peripheral nerve regeneration were studied using a rat sciatic nerve transection model. Ninety male healthy White Wistar rats were divided into three experimental groups (n = 15), randomly: Sham-operation (SHAM), transected control (TC), chitosan conduit (Chit) and three treatment groups (Vit E, PQQ and PQQ + Vit E). In SHAM group after anesthesia, left sciatic nerve was exposed through a gluteal muscle incision and after homeostasis muscle was sutured. In Chit group left sciatic nerve was exposed the same way and transected proximal to tibio-peroneal bifurcation leaving a 10-mm gap. Proximal and distal stumps were each inserted into a chitosan tube. In treatment groups the tube was implanted the same way and filled with Vit E, PQQ and PQQ + Vit E. Each group was subdivided into three subgroups of six animals each and were studied 4, 8, 12 weeks after surgery. Functional and electrophysiological studies, and gastrocnemius muscle mass measurement confirmed faster and better recovery of regenerated axons in Vit E + PQQ combination compared to Vit E or PQQ solely (P < 0.05). Morphometric indices of regenerated fibers showed number and diameter of the myelinated fibers in PQQ + Vit E was significantly higher than in other treatment groups. In immunohistochemistry, location of reactions to S-100 in PQQ + Vit E was clearly more positive than in other treatment groups. Response to PQQ + Vit E treatment demonstrates that it influences and improves functional recovery of peripheral nerve regeneration. PMID:24129003

  2. Acellular Biomaterials: An Evolving Alternative to Cell-Based Therapies

    PubMed Central

    Burdick, Jason A.; Mauck, Robert L.; Gorman, Joseph H.; Gorman, Robert C.

    2014-01-01

    Acellular biomaterials can stimulate the local environment to repair tissues without the regulatory and scientific challenges of cell-based therapies. A greater understanding of the mechanisms of such endogenous tissue repair is furthering the design and application of these biomaterials. We discuss recent progress in acellular materials for tissue repair, using cartilage and cardiac tissues as examples of applications with substantial intrinsic hurdles, but where human translation is now occurring. PMID:23486777

  3. Unexpected soft tissue changes in response to root coverage using an acellular dermal matrix allograft: 12–year follow up.

    PubMed

    Batista, Eraldo L; Goergen, Josiane E; Machado, Larissa L; Santayana de Lima, Eduardo M

    2014-01-01

    A woman undergoing orthodontic treatment presented with recession and reduced keratinized gingiva on teeth 31 and 41. The patient declined creation of a donor site for conventional autogenous connective soft tissue grafting and opted for an acellular dermal matrix soft tissue substitute for root coverage. Orthodontic treatment followed, and the patient returned for orthognatic surgery after 12 years. Long-term follow up revealed that root coverage remained stable over time and creeping attachment on both teeth was observed. Unexpectedly, an increase in the width of keratinized gingiva was observed. No adverse effects of orthodontic treatment carried out after grafting were observed. PMID:25437945

  4. Effective management of major lower extremity wounds using an acellular regenerative tissue matrix: a pilot study.

    PubMed

    Brigido, Stephen A; Boc, Steven F; Lopez, Ramon C

    2004-01-01

    Wound healing is a significant problem in orthopedics. Graftjacket tissue matrix (Wright Medical Technology, Inc, Arlington, Tenn), a novel acellular regenerative tissue matrix, has been designed to aid wound closure. A prospective, randomized study was initiated to determine the efficacy of this tissue product in wound repair compared with conventional treatment. Lower extremity wounds are refractile to healing in patients with diabetes mellitus. Therefore, researchers used diabetic foot ulcers to evaluate the efficacy of GraftJacket tissue matrix in wound repair. Only a single administration of the tissue matrix was required. After 1 month of treatment, preliminary results demonstrate that this novel tissue matrix promotes faster healing at a statistically significant rate over conventional treatment. Because wounds in this series of patients are deep and circulation around the wound is poor, the preliminary results suggest that this tissue matrix will be applicable to other types of orthopedic wounds. PMID:14763548

  5. Vein to artery grafts. An experimental study of reinnervation of the graft wall.

    PubMed Central

    Meagher, S; McGeachie, J; Prendergast, F

    1984-01-01

    Iliolumbar vein to iliac artery grafts were placed in 21 rats by microsurgical techniques. Graft innervation was examined at five time intervals between 1 and 32 weeks after surgery. Nerve fibers were demonstrated microscopically by formaldehyde-induced fluorescence of catecholamines. The morphology and degree of graft innervation were assessed, semiquantitatively, relative to the contralateral iliac artery (control) within each animal. Nerves were seen in the graft region as early as 2 weeks, but it was not until 4 weeks that they were present along its length (5 mm). The formation of a nerve plexus in the adventitia surrounding the graft was evident at 8 weeks. By 16 weeks the degree of innervation in the graft had increased to a level that was greater than the control iliac artery in three of four animals examined. Grafts at 32 weeks were also hyperinnervated. However, the morphology of this innervation was different from the control arteries; nerve fibers were finer, not varicosed, and were located at a greater distance from the outer layer of smooth muscle cells. The origin of the nerves appeared to be collateral sprouts from nerves supplying the adjacent iliac vein and also from invading vasa vasorum. The host iliac artery nerve plexus did not contribute to graft innervation. Images FIG. 1. PMID:6465969

  6. Ligament reconstruction with tendon interposition using an acellular dermal allograft for thumb carpometacarpal arthritis.

    PubMed

    Kokkalis, Zinon T; Zanaros, George; Sotereanos, Dean G

    2009-03-01

    Ligament reconstruction tendon interposition arthroplasty is currently the preferred technique for carpometacarpal joint arthritis of the thumb by most surgeons. Despite its efficacy, morbidity has been associated with the harvest of the flexor carpi radialis tendon. Using an allograft as material for arthroplasty, donor site morbidity is avoided. In this report, we present our surgical technique to perform ligament reconstruction tendon interposition arthroplasty using an acellular dermal matrix allograft (GraftJacket) in patients with Eaton stages II, III, and IV symptomatic first carpometacarpal arthritis.One hundred thumbs with trapeziometacarpal osteoarthritis underwent surgical treatment using GraftJacket allograft instead of the flexor carpi radialis tendon autograft. Each patient was followed for a minimum of 12 months. The surgical procedure included trapezial excision and identification of the flexor carpi radialis. The allograft was cut to create a 15-cm strip. The ligament reconstruction was performed by passing the strip around the flexor carpi radialis tendon and suturing it to the base of the thumb metacarpal base through an intramedullary drill hole. The remaining portion of the allograft was fashioned as an interposition mass (anchovy) and interposed between the scaphoid and the base of the first metacarpal.All but 1 patient experienced significant improvement in his or her pain scale rating and grip and pinch strengths. Outcomes from this study compare very favorably with those of other series. No patients experienced a foreign body reaction or infection in this series. We believe that the use of an acellular dermal allograft for both ligament reconstruction and tendon interposition provides a safe and an effective alternative technique for the treatment of advanced first carpometacarpal arthritis. PMID:19276927

  7. Bone Grafts

    MedlinePlus

    A bone graft transplants bone tissue. Surgeons use bone grafts to repair and rebuild diseased bones in your hips, knees, spine, and sometimes other bones and joints. Grafts can also repair bone loss caused by some ...

  8. Acellular Dermal Matrix in Rotator Cuff Surgery.

    PubMed

    Cooper, Joseph; Mirzayan, Raffy

    2016-01-01

    The success of rotator cuff repair (RCR) surgery can be measured clinically (validated outcome scores, range of motion) as well as structurally (re-tear rates using imaging studies). Regardless of repair type or technique, most studies have shown that patients do well clinically. However, multiple studies have also shown that structurally, the failure rate can be very high. A variety of factors, including poor tendon quality, age over 63 years, smoking, advanced fatty infiltration into the muscle, and the inability of the tendon to heal to bone, have been implicated as the cause of the high re-tear rate in RCRs. The suture-tendon interface is felt to be the weakest link in the RCR construct, and suture pullout through the tendon is believed to be the most common method of failure. This review of the published literature seeks to determine if there is support for augmentation of RCR with acellular dermal matrices to strengthen the suture-tendon interface and reduce the re-tear rate. PMID:27552454

  9. Augmentation of partially regenerated nerves by end-to-side side-to-side grafting neurotization: experience based on eight late obstetric brachial plexus cases

    PubMed Central

    2006-01-01

    Objective The effect of end-to-side neurotization of partially regenerated recipient nerves on improving motor power in late obstetric brachial plexus lesions, so-called nerve augmentation, was investigated. Methods Eight cases aged 3 – 7 years were operated upon and followed up for 4 years (C5,6 rupture C7,8T1 avulsion: 5; C5,6,7,8 rupture T1 avulsion:1; C5,6,8T1 rupture C7 avulsion:1; C5,6,7 ruptureC8 T1 compression: one 3 year presentation after former neurotization at 3 months). Grade 1–3 muscles were neurotized. Grade0 muscles were neurotized, if the electromyogram showed scattered motor unit action potentials on voluntary contraction without interference pattern. Donor nerves included: the phrenic, accessory, descending and ascending loops of the ansa cervicalis, 3rd and 4th intercostals and contralateral C7. Results Superior proximal to distal regeneration was observed firstly. Differential regeneration of muscles supplied by the same nerve was observed secondly (superior supraspinatus to infraspinatus regeneration). Differential regeneration of antagonistic muscles was observed thirdly (superior biceps to triceps and pronator teres to supinator recovery). Differential regeneration of fibres within the same muscle was observed fourthly (superior anterior and middle to posterior deltoid regeneration). Differential regeneration of muscles having different preoperative motor powers was noted fifthly; improvement to Grade 3 or more occurred more in Grade2 than in Grade0 or Grade1 muscles. Improvements of cocontractions and of shoulder, forearm and wrist deformities were noted sixthly. The shoulder, elbow and hand scores improved in 4 cases. Limitations The sample size is small. Controls are necessary to rule out any natural improvement of the lesion. There is intra- and interobserver variability in testing muscle power and cocontractions. Conclusion Nerve augmentation improves cocontractions and muscle power in the biceps, pectoral muscles, supraspinatus

  10. Neoinnervation and neovascularization of acellular pericardial-derived scaffolds in myocardial infarcts.

    PubMed

    Gálvez-Montón, Carolina; Fernandez-Figueras, M Teresa; Martí, Mercè; Soler-Botija, Carolina; Roura, Santiago; Perea-Gil, Isaac; Prat-Vidal, Cristina; Llucià-Valldeperas, Aida; Raya, Ángel; Bayes-Genis, Antoni

    2015-01-01

    Engineered bioimplants for cardiac repair require functional vascularization and innervation for proper integration with the surrounding myocardium. The aim of this work was to study nerve sprouting and neovascularization in an acellular pericardial-derived scaffold used as a myocardial bioimplant. To this end, 17 swine were submitted to a myocardial infarction followed by implantation of a decellularized human pericardial-derived scaffold. After 30 days, animals were sacrificed and hearts were analyzed with hematoxylin/eosin and Masson's and Gallego's modified trichrome staining. Immunohistochemistry was carried out to detect nerve fibers within the cardiac bioimplant by using βIII tubulin and S100 labeling. Isolectin B4, smooth muscle actin, CD31, von Willebrand factor, cardiac troponin I, and elastin antibodies were used to study scaffold vascularization. Transmission electron microscopy was performed to confirm the presence of vascular and nervous ultrastructures. Left ventricular ejection fraction (LVEF), cardiac output (CO), stroke volume, end-diastolic volume, end-systolic volume, end-diastolic wall mass, and infarct size were assessed by using magnetic resonance imaging (MRI). Newly formed nerve fibers composed of several amyelinated axons as the afferent nerve endings of the heart were identified by immunohistochemistry. Additionally, neovessel formation occurred spontaneously as small and large isolectin B4-positive blood vessels within the scaffold. In summary, this study demonstrates for the first time the neoformation of vessels and nerves in cell-free cardiac scaffolds applied over infarcted tissue. Moreover, MRI analysis showed a significant improvement in LVEF (P = 0.03) and CO (P = 0.01) and a 43 % decrease in infarct size (P = 0.007). PMID:26205795

  11. Effect of Artificial Nerve Conduit Vascularization on Peripheral Nerve in a Necrotic Bed

    PubMed Central

    Iijima, Yuki; Murayama, Akira; Takeshita, Katsushi

    2016-01-01

    Background: Several types of artificial nerve conduit have been used for bridging peripheral nerve gaps as an alternative to autologous nerves. However, their efficacy in repairing nerve injuries accompanied by surrounding tissue damage remains unclear. We fabricated a novel nerve conduit vascularized by superficial inferior epigastric (SIE) vessels and evaluated whether it could promote axonal regeneration in a necrotic bed. Methods: A 15-mm nerve conduit was implanted beneath the SIE vessels in the groin of a rat to supply it with blood vessels 2 weeks before nerve reconstruction. We removed a 13-mm segment of the sciatic nerve and then pressed a heated iron against the dorsal thigh muscle to produce a burn. The defects were immediately repaired with an autograft (n = 10), nerve conduit graft (n = 8), or vascularized nerve conduit graft (n = 8). Recovery of motor function was examined for 18 weeks after surgery. The regenerated nerves were electrophysiologically and histologically evaluated. Results: The vascularity of the nerve conduit implanted beneath the SIE vessels was confirmed histologically 2 weeks after implantation. Between 14 and 18 weeks after surgery, motor function of the vascularized conduit group was significantly better than that of the nonvascularized conduit group. Electrophysiological and histological evaluations revealed that although the improvement did not reach the level of reinnervation achieved by an autograft, the vascularized nerve conduit improved axonal regeneration more than did the conduit alone. Conclusion: Vascularization of artificial nerve conduits accelerated peripheral nerve regeneration, but further research is required to improve the quality of nerve regeneration. PMID:27257595

  12. Skin flaps and grafts - self-care

    MedlinePlus

    ... skin infection Surgery for skin cancer Venous ulcers , pressure ulcers , or diabetic ulcers that do not heal After mastectomy or amputation Donor sites for grafts and flaps are chosen ... surgery than the wound due to newly exposed nerve endings.

  13. Own Experience From The Use Of A Substitute Of An Allogeneic Acellular Dermal Matrix Revitalized With In Vitro Cultured Skin Cells In Clinical Practice.

    PubMed

    Łabuś, Wojciech; Kawecki, Marek; Glik, Justyna; Maj, Mariusz; Kitala, Diana; Misiuga, Marcelina; Klama-Baryła, Agnieszka; Kraut, Małgorzata; Nowak, Mariusz

    2015-10-01

    As a result of the removal of cells from human allogeneic dermis, a collagen scaffold is obtained, which can be populated de novo with autologous/allogeneic skin cells and transplanted onto the area of skin loss. The optimal method for production of acellular dermal matrices (ADM) has been selected. Three female patients (a mean age of 54 years) were subjected to the transplantation of either autologous or allogeneic keratinocytes and fibroblasts into the holes of acellular dermal matrix (ADM) mesh graft. The method for burn wound treatment based on the use of a viable dermal-epidermal skin substitute (based on ADM and in vitro cultured fibroblasts and keratinocytes) may be the optimal method of burn treatment. PMID:26812752

  14. Challenges to acellular biological scaffold mediated skeletal muscle tissue regeneration.

    PubMed

    Corona, Benjamin T; Greising, Sarah M

    2016-10-01

    Volumetric muscle loss (VML) injuries present a complex and heterogeneous clinical problem that results in a chronic loss of muscle tissue and strength. The primary limitation to muscle tissue regeneration after VML injury is the frank loss of all native muscle constituents in the defect, especially satellite cells and the basal lamina. Recent advancements in regenerative medicine have set forth encouraging and emerging translational and therapeutic options for these devastating injuries including the surgical implantation of acellular biological scaffolds. While these biomaterials can modulate the wound environment, the existing data do not support their capacity to promote appreciable muscle fiber regeneration that can contribute to skeletal muscle tissue functional improvements. An apparent restriction of endogenous satellite cell (i.e., pax7(+)) migration to acellular biological scaffolds likely underlies this deficiency. This work critically evaluates the role of an acellular biological scaffold in orchestrating skeletal muscle tissue regeneration, specifically when used as a regenerative medicine approach for VML injury. PMID:27472161

  15. Experimental study on nerve regeneration through the basement membrane tubes of the nerve, muscle, and artery.

    PubMed

    Itoh, S; Shinomiya, K; Samejima, H; Ohta, T; Ishizuki, M; Ichinose, S

    1996-01-01

    We evaluated neurotization after transplantation with lyophilized nerves, muscles, and arteries, and examined the possibility of practical application of long bridging grafts. Grafts of 10 mm and 25 mm of lyophilized nerves, muscles, and arteries harvested from Fisher rats were transplanted to the sciatic nerves of recipient Lewis rats. The histological changes undergone by short grafts were observed at weekly intervals. The sham-operated and isograft groups were used to compare the results of long grafts. In both the nerve and muscle-graft group, regenerated axons grew out through the residual basement membrane tube. But in the muscle graft group, phagocytosis of myofibril debris took longer than that of degenerated axons. No statistical differences were found between results of TSI, induced EMG, and quantitative analysis of myelinated axons in the nerve and muscle graft groups. No neurotization was noted in the long artery graft. In long grafts, laminin found on the basement membrane may not be sufficient to accelerate neurotization, and arteries should not be used for tubulization. PMID:9431514

  16. Use of acellular dermal replacement in reconstruction of nonhealing lower extremity wounds.

    PubMed

    Kahn, Steven Alexander; Beers, Ryan J; Lentz, Christopher W

    2011-01-01

    Dermal templates are well established in the treatment of burn wounds and acute nonburn wounds. However, the literature regarding their use for reconstruction of chronic, nonhealing wounds is limited. This study describes a series of patients with chronic wounds reconstructed with a commercially available bilayer, acellular dermal replacement (ADR) containing a collagen-glycosaminoglycan dermal template and a silicone outer layer. A retrospective review was performed of 10 patients treated for chronic wounds with ADR and negative pressure dressing followed by split-thickness skin graft between July 2006 and January 2009. Data collected included age, gender, comorbidities, medications, wound type or location, wound size, the number of applications of ADR, the amount of ADR applied (in square centimeter), the amount of time between ADR placement and grafting, complications, need for reoperation, and percentage of graft take after 5 and 14 days. The mean age of study subjects was 44 years. All patients in the study had comorbidities that interfere with wound healing and were treated for lower extremity wounds (four to legs, five to ankles, and one to foot). The wounds had a variety of causative factors including venostasis ulcers (6, 60%), trauma in diabetic patients (2, 20%), brown recluse bite (1, 10%), and a wound caused from purpura fulminans (1, 10%). The average wound size and amount of ADR applied was 162±182 cm². Each patient required only one application of ADR. The average time between ADR placement and skin grafting was 36.5 days. The mean percentage of graft take at 5 days was 89.55%, 14 days was 90%, and 21 days was 87.3%. Only two patients required regrafting, and one of these grafts was lost because of patient noncompliance. ADR can be used successfully in the treatment of chronic wounds. ADR provides direct wound coverage and can conform to a variety of anatomical sites. This study demonstrates that the use of ADR in treating chronic wounds results

  17. Glycerolized Reticular Dermis as a New Human Acellular Dermal Matrix: An Exploratory Study.

    PubMed

    Ferrando, Pietro Maria; Balmativola, Davide; Cambieri, Irene; Scalzo, Maria Stella; Bergallo, Massimiliano; Annaratone, Laura; Casarin, Stefania; Fumagalli, Mara; Stella, Maurizio; Sapino, Anna; Castagnoli, Carlotta

    2016-01-01

    Human Acellular Dermal Matrices (HADM) are employed in various reconstructive surgery procedures as scaffolds for autologous tissue regeneration. The aim of this project was to develop a new type of HADM for clinical use, composed of glycerolized reticular dermis decellularized through incubation and tilting in Dulbecco's Modified Eagle's Medium (DMEM). This manufacturing method was compared with a decellularization procedure already described in the literature, based on the use of sodium hydroxide (NaOH), on samples from 28 donors. Cell viability was assessed using an MTT assay and microbiological monitoring was performed on all samples processed after each step. Two surgeons evaluated the biomechanical characteristics of grafts of increasing thickness. The effects of the different decellularization protocols were assessed by means of histological examination and immunohistochemistry, and residual DNA after decellularization was quantified using a real-time TaqMan MGB probe. Finally, we compared the results of DMEM based decellularization protocol on reticular dermis derived samples with the results of the same protocol applied on papillary dermis derived grafts. Our experimental results indicated that the use of glycerolized reticular dermis after 5 weeks of treatment with DMEM results in an HADM with good handling and biocompatibility properties. PMID:26918526

  18. Glycerolized Reticular Dermis as a New Human Acellular Dermal Matrix: An Exploratory Study

    PubMed Central

    Ferrando, Pietro Maria; Balmativola, Davide; Cambieri, Irene; Scalzo, Maria Stella; Bergallo, Massimiliano; Annaratone, Laura; Casarin, Stefania; Fumagalli, Mara; Stella, Maurizio; Sapino, Anna; Castagnoli, Carlotta

    2016-01-01

    Human Acellular Dermal Matrices (HADM) are employed in various reconstructive surgery procedures as scaffolds for autologous tissue regeneration. The aim of this project was to develop a new type of HADM for clinical use, composed of glycerolized reticular dermis decellularized through incubation and tilting in Dulbecco’s Modified Eagle’s Medium (DMEM). This manufacturing method was compared with a decellularization procedure already described in the literature, based on the use of sodium hydroxide (NaOH), on samples from 28 donors. Cell viability was assessed using an MTT assay and microbiological monitoring was performed on all samples processed after each step. Two surgeons evaluated the biomechanical characteristics of grafts of increasing thickness. The effects of the different decellularization protocols were assessed by means of histological examination and immunohistochemistry, and residual DNA after decellularization was quantified using a real-time TaqMan MGB probe. Finally, we compared the results of DMEM based decellularization protocol on reticular dermis derived samples with the results of the same protocol applied on papillary dermis derived grafts. Our experimental results indicated that the use of glycerolized reticular dermis after 5 weeks of treatment with DMEM results in an HADM with good handling and biocompatibility properties. PMID:26918526

  19. Platform Technologies for Decellularization, Tunic-Specific Cell Seeding, and In Vitro Conditioning of Extended Length, Small Diameter Vascular Grafts

    PubMed Central

    Fercana, George; Bowser, Devon; Portilla, Margarita; Langan, Eugene M.; Carsten, Christopher G.; Cull, David L.; Sierad, Leslie N.

    2014-01-01

    The aim of this study was to generate extended length, small diameter vascular scaffolds that could serve as potential grafts for treatment of acute ischemia. Biological tissues are considered excellent scaffolds, which exhibit adequate biological, mechanical, and handling properties; however, they tend to degenerate, dilate, and calcify after implantation. We hypothesized that chemically stabilized acellular arteries would be ideal scaffolds for development of vascular grafts for peripheral surgery applications. Based on promising historical data from our laboratory and others, we chose to decellularize bovine mammary and femoral arteries and test them as scaffolds for vascular grafting. Decellularization of such long structures required development of a novel “bioprocessing” system and a sequence of detergents and enzymes that generated completely acellular, galactose-(α1,3)-galactose (α-Gal) xenoantigen-free scaffolds with preserved collagen, elastin, and basement membrane components. Acellular arteries exhibited excellent mechanical properties, including burst pressure, suture holding strength, and elastic recoil. To reduce elastin degeneration, we treated the scaffolds with penta-galloyl glucose and then revitalized them in vitro using a tunic-specific cell approach. A novel atraumatic endothelialization protocol using an external stent was also developed for the long grafts and cell-seeded constructs were conditioned in a flow bioreactor. Both decellularization and revitalization are feasible but cell retention in vitro continues to pose challenges. These studies support further efforts toward clinical use of small diameter acellular arteries as vascular grafts. PMID:24749889

  20. Pinched Nerve

    MedlinePlus

    ... Enhancing Diversity Find People About NINDS NINDS Pinched Nerve Information Page Table of Contents (click to jump ... being done? Clinical Trials Organizations What is Pinched Nerve? The term "pinched nerve" is a colloquial term ...

  1. Nerve biopsy

    MedlinePlus

    Nerve biopsy may be done to help diagnose: Axon degeneration (destruction of the axon portion of the nerve cell) Damage to the ... Demyelination Inflammation of the nerve Leprosy Loss of axon tissue Metabolic neuropathies Necrotizing vasculitis Sarcoidosis

  2. Use of an acellular flowable dermal replacement scaffold on lower extremity sinus tract wounds: a retrospective series.

    PubMed

    Brigido, Stephen A; Schwartz, Edward; McCarroll, Raymond; Hardin-Young, Janet

    2009-04-01

    A novel injectable human dermal matrix has been developed for the treatment of complex diabetic sinus tract wounds. Bioengineered grafts are commercially available that have been somewhat effective in treating chronic wounds such as diabetic foot ulcers; however, these bioengineered grafts are only available in sheet form. These therapies are less effective in treating complex or irregularly shaped wounds that demonstrate tunnels or extensions into deep soft tissue. One acellular graft (GRAFTJACKET, Matrix, Wright Medical Technology, Arlington, Tennessee) that has been shown to effectively treat open wounds is also available in a micronized form (GRAFTJACKET Xpress Scaffold, Wright Medical Technology). This human dermal graft forms a flowable soft tissue scaffold that can be delivered via syringe into tunneling wounds. In this retrospective series, 12 patients with deep tunneling wounds were treated with GRAFTJACKET Xpress Scaffold and followed for 12 weeks. Complete wound healing was achieved in 10 of 12 patients within the 12-week evaluation. The average time to complete healing was 8.5 weeks, whereas the average time to depth healing was 7.8 weeks. The data from the study suggest that this injectable human dermal matrix has unique properties that allow it to facilitate healing of complex tunneling diabetic foot ulcers. The material is easy to prepare and inject into the wound, thereby preventing the necessity of extensive surgical exposure. The matrix supports neo-subcutaneous tissue formation and allows the body to rapidly repair these wounds. PMID:19825754

  3. Design and development of multilayer vascular graft

    NASA Astrophysics Data System (ADS)

    Madhavan, Krishna

    2011-07-01

    strength, showed that the multilayer graft possessed properties mimicking those of native vessels. Achieving these FDA-required functional properties is essential because they play critical roles in graft performances in vivo such as thrombus formation, occlusion, healing, and bleeding. In addition, cell studies and animal studies have been performed on the multilayer graft. Our results show that the multilayer graft support mimetic vascular culture of cells and the acellular graft serves as an artery equivalent in vivo to sustain the physiological conditions and promote appropriate cellular activity. In conclusion, the newly-developed hybrid multilayer graft provides a proper balance of biomechanical and biochemical properties and demonstrates the potential for the use of vascular tissue engineering and regeneration.

  4. Peripheral nerve conduits: technology update

    PubMed Central

    Arslantunali, D; Dursun, T; Yucel, D; Hasirci, N; Hasirci, V

    2014-01-01

    Peripheral nerve injury is a worldwide clinical problem which could lead to loss of neuronal communication along sensory and motor nerves between the central nervous system (CNS) and the peripheral organs and impairs the quality of life of a patient. The primary requirement for the treatment of complete lesions is a tension-free, end-to-end repair. When end-to-end repair is not possible, peripheral nerve grafts or nerve conduits are used. The limited availability of autografts, and drawbacks of the allografts and xenografts like immunological reactions, forced the researchers to investigate and develop alternative approaches, mainly nerve conduits. In this review, recent information on the various types of conduit materials (made of biological and synthetic polymers) and designs (tubular, fibrous, and matrix type) are being presented. PMID:25489251

  5. A bioengineered peripheral nerve construct using aligned peptide amphiphile nanofibers

    PubMed Central

    Yalom, Anisa; Berns, Eric J.; Stephanopoulos, Nicholas; McClendon, Mark T.; Segovia, Luis A.; Spigelman, Igor; Stupp, Samuel I.; Jarrahy, Reza

    2014-01-01

    Peripheral nerve injuries can result in lifelong disability. Primary coaptation is the treatment of choice when the gap between transected nerve ends is short. Long nerve gaps seen in more complex injuries often require autologous nerve grafts or nerve conduits implemented into the repair. Nerve grafts, however, cause morbidity and functional loss at donor sites, which are limited in number. Nerve conduits, in turn, lack an internal scaffold to support and guide axonal regeneration, resulting in decreased efficacy over longer nerve gap lengths. By comparison, peptide amphiphiles (PAs) are molecules that can self-assemble into nanofibers, which can be aligned to mimic the native architecture of peripheral nerve. As such, they represent a potential substrate for use in a bioengineered nerve graft substitute. To examine this, we cultured Schwann cells with bioactive PAs (RGDS-PA, IKVAV-PA) to determine their ability to attach to and proliferate within the biomaterial. Next, we devised a PA construct for use in a peripheral nerve critical sized defect model. Rat sciatic nerve defects were created and reconstructed with autologous nerve, PLGA conduits filled with various forms of aligned PAs, or left unrepaired. Motor and sensory recovery were determined and compared among groups. Our results demonstrate that Schwann cells are able to adhere to and proliferate in aligned PA gels, with greater efficacy in bioactive PAs compared to the backbone-PA alone. In vivo testing revealed recovery of motor and sensory function in animals treated with conduit/PA constructs comparable to animals treated with autologous nerve grafts. Functional recovery in conduit/PA and autologous graft groups was significantly faster than in animals treated with empty PLGA conduits. Histological examinations also demonstrated increased axonal and Schwann cell regeneration within the reconstructed nerve gap in animals treated with conduit/PA constructs. These results indicate that PA nanofibers may

  6. Coverage of gingival recession defects using acellular dermal matrix allograft with or without beta-tricalcium phosphate.

    PubMed

    Okubo, Nobuki; Fujita, Takahisa; Ishii, Yoshihito; Ota, Mikio; Shibukawa, Yoshihiro; Yamada, Satoru

    2013-01-01

    The aim of this study was to investigate the effect of beta-tricalcium phosphate (β-TCP) particles in combination with acellular dermal matrix (ADM) allograft in gingival recession. Experimental gingival recession defects were created in beagle dogs and randomly assigned to one of the following groups: ADM, ADM + β-TCP, or coronally positioned flap (CPF; control). Tissues were histologically examined at 4, 8, or 16 weeks following treatment. A greater thickness of gingiva was observed at the sites treated in both the ADM + β-TCP and ADM groups than in the CPF group. The ADM + β-TCP group showed a statistically significant increase in both new bone and cementum formations compared to the ADM group. The results suggest that the combination of β-TCP and ADM is more effective in promoting new bone and cementum formations than ADM graft alone. PMID:21862508

  7. Chitosan-film enhanced chitosan nerve guides for long-distance regeneration of peripheral nerves.

    PubMed

    Meyer, Cora; Stenberg, Lena; Gonzalez-Perez, Francisco; Wrobel, Sandra; Ronchi, Giulia; Udina, Esther; Suganuma, Seigo; Geuna, Stefano; Navarro, Xavier; Dahlin, Lars B; Grothe, Claudia; Haastert-Talini, Kirsten

    2016-01-01

    Biosynthetic nerve grafts are developed in order to complement or replace autologous nerve grafts for peripheral nerve reconstruction. Artificial nerve guides currently approved for clinical use are not widely applied in reconstructive surgery as they still have limitations especially when it comes to critical distance repair. Here we report a comprehensive analysis of fine-tuned chitosan nerve guides (CNGs) enhanced by introduction of a longitudinal chitosan film to reconstruct critical length 15 mm sciatic nerve defects in adult healthy Wistar or diabetic Goto-Kakizaki rats. Short and long term investigations demonstrated that the CNGs enhanced by the guiding structure of the introduced chitosan film significantly improved functional and morphological results of nerve regeneration in comparison to simple hollow CNGs. Importantly, this was detectable both in healthy and in diabetic rats (short term) and the regeneration outcome almost reached the outcome after autologous nerve grafting (long term). Hollow CNGs provide properties likely leading to a wider clinical acceptance than other artificial nerve guides and their performance can be increased by simple introduction of a chitosan film with the same advantageous properties. Therefore, the chitosan film enhanced CNGs represent a new generation medical device for peripheral nerve reconstruction. PMID:26517563

  8. Schwann cell basal lamina and nerve regeneration.

    PubMed

    Ide, C; Tohyama, K; Yokota, R; Nitatori, T; Onodera, S

    1983-12-12

    Nerve segments approximately 7 mm long were excised from the predegenerated sciatic nerves of mice, and treated 5 times by repetitive freezing and thawing to kill the Schwann cells. Such treated nerve segments were grafted into the original places so as to be in contact with the proximal stumps. The animals were sacrificed 1, 2, 3, 5, 7 and 10 days after the grafting. The grafts were examined by electron microscopy in the middle part of the graft, i.e. 3-4 mm distal to the proximal end and/or near the proximal and distal ends of the graft. In other instances, the predegenerated nerve segments were minced with a razor blade after repetitive freezing and thawing. Such minced nerves were placed in contact with the proximal stumps of the same nerves. The animals were sacrificed 10 days after the grafting. Within 1-2 days after grafting, the dead Schwann cells had disintegrated into fragments. They were then gradually phagocytosed by macrophages. The basal laminae of Schwann cells, which were not attacked by macrophages, remained as empty tubes (basal lamina scaffolds). In the grafts we examined, no Schwann cells survived the freezing and thawing process. The regenerating axons always grew out through such basal lamina scaffolds, being in contact with the inner surface of the basal lamina (i.e. the side originally facing the Schwann cell plasma membrane). No axons were found outside of the scaffolds. One to two days after grafting, the regenerating axons were not associated with Schwann cells, but after 5-7 days they were accompanied by Schwann cells which were presumed to be migrating along axons from the proximal stumps. Ten days after grafting, proliferating Schwann cells observed in the middle part of the grafts had begun to sort out axons. In the grafts of minced nerves, the fragmented basal laminae of the Schwann cells re-arranged themselves into thicker strands or small aggregations of basal laminae. The regenerating axons, without exception, attached to one side

  9. Comparison of toxicities of acellular pertussis vaccine with whole cell pertussis vaccine in experimental animals.

    PubMed

    Sato, Y; Sato, H

    1991-01-01

    There is no suitable animal model for pertussis encephalopathy in humans. In this study, we have compared the toxicity of acellular pertussis vaccine with whole cell pertussis vaccine in mice or guinea pigs. Two lots of acellular and two lots of whole cell vaccine produced in different countries were assayed in the test. 1. There was no statistical difference in mouse protective potency between these acellular or whole cell pertussis vaccines. 2. There were no differences in chemical ingredients between acellular and whole cell pertussis vaccines except for protein nitrogen content. The protein nitrogen content of whole cell vaccine was at least three times higher than that of the acellular product. 3. Anti-PT antibody productivity of the acellular vaccine was higher than that of the whole cell vaccine. 4. Anti-agglutinogen antibody productivity of the whole cell vaccine was higher than that of the acellular vaccine. 5. There was no pyrogenic activity with the acellular vaccine, but high pyrogenicity was seen with whole cell vaccine. 6. There was high body-weight decreasing toxicity in mice and guinea pigs by the whole cell vaccine. 7. The mice died when they received whole cell pertussis vaccine iv, but no deaths occurred in the mice which received acellular pertussis vaccine. PMID:1778317

  10. In vivo integration of poly(ε-caprolactone)/gelatin nanofibrous nerve guide seeded with teeth derived stem cells for peripheral nerve regeneration.

    PubMed

    Beigi, Mohammad-Hossein; Ghasemi-Mobarakeh, Laleh; Prabhakaran, Molamma P; Karbalaie, Khadijeh; Azadeh, Hamid; Ramakrishna, Seeram; Baharvand, Hossein; Nasr-Esfahani, Mohammad-Hossein

    2014-12-01

    Artificial nanofiber nerve guides have gained huge interest in bridging nerve gaps and associated peripheral nerve regeneration due to its high surface area, flexibility and porous structure. In this study, electrospun poly (ε-caprolactone)/gelatin (PCL/Gel) nanofibrous mats were fabricated, rolled around a copper wire and fixed by medical grade adhesive to obtain a tubular shaped bio-graft, to bridge 10 mm sciatic nerve gap in in vivo rat models. Stem cells from human exfoliated deciduous tooth (SHED) were transplanted to the site of nerve injury through the nanofibrous nerve guides. In vivo experiments were performed in animal models after creating a sciatic nerve gap, such that the nerve gap was grafted using (i) nanofiber nerve guide (ii) nanofiber nerve guide seeded with SHED (iii) suturing, while an untreated nerve gap remained as the negative control. In vitro cell culture study was carried out for primary investigation of SHED-nanofiber interaction and its viability within the nerve guides after 2 and 16 weeks of implantation time. Walking track analysis, plantar test, electrophysiology and immunohistochemistry were performed to evaluate functional recovery during nerve regeneration. Vascularization was also investigated by hematoxilin/eosine (H&E) staining. Overall results showed that the SHED seeded on nanofibrous nerve guide could survive and promote axonal regeneration in rat sciatic nerves, whereby the biocompatible PCL/Gel nerve guide with cells can support axonal regeneration and could be a promising tissue engineered graft for peripheral nerve regeneration. PMID:24677613

  11. Nerve biopsy

    MedlinePlus

    ... Loss of axon tissue Metabolic neuropathies Necrotizing vasculitis Sarcoidosis Risks Allergic reaction to the local anesthetic Discomfort ... Neurosarcoidosis Peripheral neuropathy Primary amyloidosis Radial nerve dysfunction Sarcoidosis Tibial nerve dysfunction Update Date 6/1/2015 ...

  12. Nerve conduction

    MedlinePlus Videos and Cool Tools

    ... the spinal cord to muscles and sensory receptors. A peripheral nerve is composed of nerve bundles (fascicles) ... two neurons, it must first be converted to a chemical signal, which then crosses a space of ...

  13. Treatment of severe burn with DermACELL®, an acellular dermal matrix

    PubMed Central

    Chen, Shyi-Gen; Tzeng, Yuan-Sheng; Wang, Chih-Hsin

    2012-01-01

    For treatment of skin burn injuries, there exist several methods of treatment related to tissue regeneration, including the use of autograft skin and cryopreserved skin. However, each method has drawbacks. An alternative method for tissue regeneration is allograft acellular dermal matrix, with potential as a biocompatible scaffold for new tissue growth. One recently produced material of this type is DermACELL®, which was used in this case presentation for treating a scar resulting from second- and third-degree burns in a 33-year-old female patient. The patient presented with significant hypertrophic scarring from the elbow to the hand and with limited wrist and elbow motion. The scarring was removed, and the patient was treated with a 1:3 mesh of DermACELL. The wound was resurfaced with a split thickness skin graft, and postoperative care included application of pressure garment and silicone sheet, as well as range of motion exercise and massage. At 30 days after DermACELL application, the wound appeared well-healed with little scar formation. At 180 days post-application, the wound continued to appear healed well without significant scar formation. Additionally, the wound was supple, and the patient experienced significant improvement in range of motion. In the case presented, DermACELL appears to have been a successful method of treatment for scarring due to severe burns by preventing further scar formation and improving range of motion. PMID:23071908

  14. Porcine acellular lung matrix for wound healing and abdominal wall reconstruction: A pilot study

    PubMed Central

    Fernandez-Moure, Joseph S; Van Eps, Jeffrey L; Rhudy, Jessica R; Cabrera, Fernando J; Acharya, Ghanashyam S; Tasciotti, Ennio; Sakamoto, Jason; Nichols, Joan E

    2016-01-01

    Surgical wound healing applications require bioprosthetics that promote cellular infiltration and vessel formation, metrics associated with increased mechanical strength and resistance to infection. Porcine acellular lung matrix is a novel tissue scaffold known to promote cell adherence while minimizing inflammatory reactions. In this study, we evaluate the capacity of porcine acellular lung matrix to sustain cellularization and neovascularization in a rat model of subcutaneous implantation and chronic hernia repair. We hypothesize that, compared to human acellular dermal matrix, porcine acellular lung matrix would promote greater cell infiltration and vessel formation. Following pneumonectomy, porcine lungs were processed and characterized histologically and by scanning electron microscopy to demonstrate efficacy of the decellularization. Using a rat model of subcutaneou implantation, porcine acellular lung matrices (n = 8) and human acellular dermal matrices (n = 8) were incubated in vivo for 6 weeks. To evaluate performance under mechanically stressed conditions, porcine acellular lung matrices (n = 7) and human acellular dermal matrices (n = 7) were implanted in a rat model of chronic ventral incisional hernia repair for 6 weeks. After 6 weeks, tissues were evaluated using hematoxylin and eosin and Masson’s trichrome staining to quantify cell infiltration and vessel formation. Porcine acellular lung matrices were shown to be successfully decellularized. Following subcutaneous implantation, macroscopic vessel formation was evident. Porcine acellular lung matrices demonstrated sufficient incorporation and showed no evidence of mechanical failure after ventral hernia repair. Porcine acellular lung matrices demonstrated significantly greater cellular density and vessel formation when compared to human acellular dermal matrix. Vessel sizes were similar across all groups. Cell infiltration and vessel formation are well-characterized metrics of incorporation

  15. Porcine acellular lung matrix for wound healing and abdominal wall reconstruction: A pilot study.

    PubMed

    Fernandez-Moure, Joseph S; Van Eps, Jeffrey L; Rhudy, Jessica R; Cabrera, Fernando J; Acharya, Ghanashyam S; Tasciotti, Ennio; Sakamoto, Jason; Nichols, Joan E

    2016-01-01

    Surgical wound healing applications require bioprosthetics that promote cellular infiltration and vessel formation, metrics associated with increased mechanical strength and resistance to infection. Porcine acellular lung matrix is a novel tissue scaffold known to promote cell adherence while minimizing inflammatory reactions. In this study, we evaluate the capacity of porcine acellular lung matrix to sustain cellularization and neovascularization in a rat model of subcutaneous implantation and chronic hernia repair. We hypothesize that, compared to human acellular dermal matrix, porcine acellular lung matrix would promote greater cell infiltration and vessel formation. Following pneumonectomy, porcine lungs were processed and characterized histologically and by scanning electron microscopy to demonstrate efficacy of the decellularization. Using a rat model of subcutaneou implantation, porcine acellular lung matrices (n = 8) and human acellular dermal matrices (n = 8) were incubated in vivo for 6 weeks. To evaluate performance under mechanically stressed conditions, porcine acellular lung matrices (n = 7) and human acellular dermal matrices (n = 7) were implanted in a rat model of chronic ventral incisional hernia repair for 6 weeks. After 6 weeks, tissues were evaluated using hematoxylin and eosin and Masson's trichrome staining to quantify cell infiltration and vessel formation. Porcine acellular lung matrices were shown to be successfully decellularized. Following subcutaneous implantation, macroscopic vessel formation was evident. Porcine acellular lung matrices demonstrated sufficient incorporation and showed no evidence of mechanical failure after ventral hernia repair. Porcine acellular lung matrices demonstrated significantly greater cellular density and vessel formation when compared to human acellular dermal matrix. Vessel sizes were similar across all groups. Cell infiltration and vessel formation are well-characterized metrics of incorporation

  16. Autograft Substitutes: Conduits and Processed Nerve Allografts.

    PubMed

    Safa, Bauback; Buncke, Gregory

    2016-05-01

    Manufactured conduits and allografts are viable alternatives to direct suture repair and nerve autograft. Manufactured tubes should have gaps less than 10 mm, and ideally should be considered as an aid to the coaptation. Processed nerve allograft has utility as a substitute for either conduit or autograft in sensory nerve repairs. There is also a growing body of evidence supporting their utility in major peripheral nerve repairs, gap repairs up to 70 mm in length, as an alternative source of tissue to bolster the diameter of a cable graft, and for the management of neuromas in non-reconstructable injuries. PMID:27094886

  17. A silk sericin/silicone nerve guidance conduit promotes regeneration of a transected sciatic nerve.

    PubMed

    Xie, Hongjian; Yang, Wen; Chen, Jianghai; Zhang, Jinxiang; Lu, Xiaochen; Zhao, Xiaobo; Huang, Kun; Li, Huili; Chang, Panpan; Wang, Zheng; Wang, Lin

    2015-10-28

    Peripheral nerve gap defects lead to significant loss of sensory or motor function. Tissue engineering has become an important alternative to nerve repair. Sericin, a major component of silk, is a natural protein whose value in tissue engineering has just begun to be explored. Here, the first time use of sericin in vivo is reported as a long-term implant for peripheral nerve regeneration. A sericin nerve guidance conduit is designed and fabricated. This conduit is highly porous with mechanical strength matching peripheral nerve tissue. It supports Schwann cell proliferation and is capable of up-regulating the transcription of glial cell derived neurotrophic factor and nerve growth factor in Schwann cells. The sericin conduit wrapped with a silicone conduit (sericin/silicone double conduits) is used for bridging repair of a 5 mm gap in a rat sciatic nerve transection model. The sericin/silicone double conduits achieve functional recovery comparable to that of autologous nerve grafting as evidenced by drastically improved nerve function and morphology. Importantly, this improvement is mainly attributed to the sericin conduit as the silicone conduit alone only produces marginal functional recovery. This sericin/silicone-double-conduit strategy offers an efficient and valuable alternative to autologous nerve grafting for repairing damaged peripheral nerve. PMID:26332703

  18. Grafts of porcine small intestinal submucosa seeded with cultured homologous smooth muscle cells for bladder repair in dogs

    PubMed Central

    2013-01-01

    Background Due to numerous complications associated to gastrointestinal augmented cystoplasty, this study aimed to analyze the anatomic repair of the bladder of 10 female dogs using grafts of porcine small intestinal submucosa (SIS) seeded with cultured homologous smooth muscle cells, and compare them with the acellular SIS grafts. Results We assessed the possible side effects and complications of each type of graft by clinical examination, abdominal ultrasound and laboratory findings. Anatomic repair of neoformed bladder was assessed by histological staining for H/E and Masson's Trichrome, analyzed with a Nikon Photomicroscope connected to the system of image analysis Image J. Conclusions We propose that SIS associated to homologous smooth cells can improve the quality of tissue repair, and consequently decrease the potential complications inherent to acellular SIS. PMID:23651843

  19. Phase II trial of whole-cell pertussis vaccine vs an acellular vaccine containing agglutinogens.

    PubMed

    Miller, E; Ashworth, L A; Robinson, A; Waight, P A; Irons, L I

    1991-01-12

    An acellular pertussis vaccine containing agglutinogens 2 and 3, pertussis toxin, and filamentous haemagglutinin was developed by the Centre for Applied Microbiology and Research in the UK. 188 infants were entered into a randomised blind trial and received either the acellular or a whole-cell vaccine, combined with diphtheria and tetanus toxoids, in a 3, 5, and 8-10 month schedule. Local reactions were similar in the two groups but significantly fewer infants had systemic symptoms after the acellular vaccine. Mean log-antibody titres to the agglutinogen and toxin components were higher with the acellular than with the whole-cell vaccine. Persistence of antibodies one year after the third dose was also better in the acellular group. PMID:1670725

  20. Whooping cough, twenty years from acellular vaccines introduction.

    PubMed

    Greco, D; Esposito, S; Tozzi, A; Pandolfi, E; Icardi, G; Giammanco, A

    2015-01-01

    Clinical pertussis resulting from infection with B. pertussis is a significant medical and public health problem, despite the huge success of vaccination that has greatly reduced its incidence. The whole cell vaccine had an undeniable success over the last 50 years, but its acceptance was strongly inhibited by fear, only partially justified, of severe side effects, but also, in the Western world, by the difficulty to enter in combination with other vaccines: today multi-vaccine formulations are essential to maintain a high vaccination coverage. The advent of acellular vaccines was greeted with enthusiasm by the public health world: in the Nineties, several controlled vaccine trials were carried out: they demonstrated a high safety and good efficacy of new vaccines. In fact, in the Western world, the acellular vaccines completely replaced the whole cells ones. In the last years, ample evidence on the variety of protection of these vaccines linked to the presence of different antigens of Bordetella pertussis was collected. It also became clear that the protection provided, on average around 80%, leaves every year a significant cohort of vaccinated susceptible even in countries with a vaccination coverage of 95%, such as Italy. Finally, it was shown that, as for the pertussis disease, protection decreases over time, to leave a proportion of adolescents and adults unprotected. Waiting for improved pertussis vaccines, the disease control today requires a different strategy that includes a booster at 5 years for infants, but also boosters for teenagers and young adults, re-vaccination of health care personnel, and possibly of pregnant women and of those who are in contact with infants (cocooning). Finally, the quest for better vaccines inevitably tends towards pertussis acellular vaccines with at least three components, which have demonstrated superior effectiveness and have been largely in use in Italy for fifteen years. PMID:26051141

  1. Rehabilitation of the trigeminal nerve

    PubMed Central

    Iro, Heinrich; Bumm, Klaus; Waldfahrer, Frank

    2005-01-01

    When it comes to restoring impaired neural function by means of surgical reconstruction, sensory nerves have always been in the role of the neglected child when compared with motor nerves. Especially in the head and neck area, with its either sensory, motor or mixed cranial nerves, an impaired sensory function can cause severe medical conditions. When performing surgery in the head and neck area, sustaining neural function must not only be highest priority for motor but also for sensory nerves. In cases with obvious neural damage to sensory nerves, an immediate neural repair, if necessary with neural interposition grafts, is desirable. Also in cases with traumatic trigeminal damage, an immediate neural repair ought to be considered, especially since reconstructive measures at a later time mostly require for interposition grafts. In terms of the trigeminal neuralgia, commonly thought to arise from neurovascular brainstem compression, a pharmaceutical treatment is considered as the state of the art in terms of conservative therapy. A neurovascular decompression of the trigeminal root can be an alternative in some cases when surgical treatment is sought after. Besides the above mentioned therapeutic options, alternative treatments are available. PMID:22073060

  2. Prevention of nerve root adhesions after laminectomy.

    PubMed

    Yong-Hing, K; Reilly, J; de Korompay, V; Kirkaldy-Willis, W H

    1980-01-01

    In repeat lumbar surgery for failure of the original operation to provide lasting relief, well-organized fibrous tissue is often noted binding together the dura, nerve roots, and erector spinae muscles. Lumbar laminectomy was carried out in 46 dogs and seven groups of animals studied. Gelfoam failed to prevent fibrosis. Free fat grafts prevented fibrosis whether the graft was placed at the laminectomy site or around the nerve roots. Vascularization of the grafts was demonstrated by injection of India ink before sacrifice. Ligamentum nuchae, which is similar to ligamentum flavum in its high elastic content, was also effective in preventing scar formation. The operative biopsy findings at reexploration in four patients who had free fat grafts following laminectomy are presented. PMID:7361199

  3. Nanofibrous nerve conduits for repair of 30-mm-long sciatic nerve defects

    PubMed Central

    Biazar, Esmaeil; Keshel, Saeed Heidari; Pouya, Majid; Rad, Hadi; Nava, Melody Omrani; Azarbakhsh, Mohammad; Hooshmand, Shirin

    2013-01-01

    It has been confirmed that nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit can promote peripheral nerve regeneration in rats. However, its efficiency in repair of over 30-mm-long sciatic nerve defects needs to be assessed. In this study, we used a nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit to bridge a 30-mm-long gap in the rat sciatic nerve. At 4 months after nerve conduit implantation, regenerated nerves were cally observed and histologically assessed. In the nanofibrous graft, the rat sciatic nerve trunk had been reconstructed by restoration of nerve continuity and formation of myelinated nerve fiber. There were Schwann cells and glial cells in the regenerated nerves. Masson's trichrome staining showed that there were no pathological changes in the size and structure of gastrocnemius muscle cells on the operated side of rats. These findings suggest that nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit is suitable for repair of long-segment sciatic nerve defects. PMID:25206536

  4. Bone Grafts

    MedlinePlus

    ... repair and rebuild diseased bones in your hips, knees, spine, and sometimes other bones and joints. Grafts can also repair bone loss caused by some types of fractures or cancers. Once your body accepts the bone ...

  5. Acellular dermal matrices in breast reconstructions - a literature review.

    PubMed

    Skovsted Yde, Simon; Brunbjerg, Mette Eline; Damsgaard, Tine Engberg

    2016-08-01

    During the last two decades, acellular dermal matrices (ADM) have been more widely used in reconstructive procedures i.e. breast reconstructions. Several, both synthetic and biologic products derived from human, porcine and bovine tissue, have been introduced. Until this point postoperative complications for the acellular dermal matrices, as a group, have been the main focus. The purpose of this literature review is to summarize the current knowledge on the each biologic product used in breast reconstructions, including product specific complication frequencies. A systematic search of the literature was performed in the PubMed and EMBASE databases, identifying 55 relevant articles, mainly evidence level III. AlloDerm seems to be associated with severe complicating matters in the reconstructive process compared to other products. This could be due to the higher number of investigating studies relative to the others. The surgical area faces certain challenges comparing results, due to surgical variance, the data collection and follow-up. More well-defined guidelines and more high-evidence randomized studies could increase the overall level of evidence in this area. PMID:26881927

  6. Human acellular dermal wound matrix: evidence and experience.

    PubMed

    Kirsner, Robert S; Bohn, Greg; Driver, Vickie R; Mills, Joseph L; Nanney, Lillian B; Williams, Marie L; Wu, Stephanie C

    2015-12-01

    A chronic wound fails to complete an orderly and timely reparative process and places patients at increased risk for wound complications that negatively impact quality of life and require greater health care expenditure. The role of extracellular matrix (ECM) is critical in normal and chronic wound repair. Not only is ECM the largest component of the dermal skin layer, but also ECM proteins provide structure and cell signalling that are necessary for successful tissue repair. Chronic wounds are characterised by their inflammatory and proteolytic environment, which degrades the ECM. Human acellular dermal matrices, which provide an ECM scaffold, therefore, are being used to treat chronic wounds. The ideal human acellular dermal wound matrix (HADWM) would support regenerative healing, providing a structure that could be repopulated by the body's cells. Experienced wound care investigators and clinicians discussed the function of ECM, the evidence related to a specific HADWM (Graftjacket(®) regenerative tissue matrix, Wright Medical Technology, Inc., licensed by KCI USA, Inc., San Antonio, TX), and their clinical experience with this scaffold. This article distills these discussions into an evidence-based and practical overview for treating chronic lower extremity wounds with this HADWM. PMID:24283346

  7. Stem cell salvage of injured peripheral nerve.

    PubMed

    Grimoldi, Nadia; Colleoni, Federica; Tiberio, Francesca; Vetrano, Ignazio G; Cappellari, Alberto; Costa, Antonella; Belicchi, Marzia; Razini, Paola; Giordano, Rosaria; Spagnoli, Diego; Pluderi, Mauro; Gatti, Stefano; Morbin, Michela; Gaini, Sergio M; Rebulla, Paolo; Bresolin, Nereo; Torrente, Yvan

    2015-01-01

    We previously developed a collagen tube filled with autologous skin-derived stem cells (SDSCs) for bridging long rat sciatic nerve gaps. Here we present a case report describing a compassionate use of this graft for repairing the polyinjured motor and sensory nerves of the upper arms of a patient. Preclinical assessment was performed with collagen/SDSC implantation in rats after sectioning the sciatic nerve. For the patient, during the 3-year follow-up period, functional recovery of injured median and ulnar nerves was assessed by pinch gauge test and static two-point discrimination and touch test with monofilaments, along with electrophysiological and MRI examinations. Preclinical experiments in rats revealed rescue of sciatic nerve and no side effects of patient-derived SDSC transplantation (30 and 180 days of treatment). In the patient treatment, motor and sensory functions of the median nerve demonstrated ongoing recovery postimplantation during the follow-up period. The results indicate that the collagen/SDSC artificial nerve graft could be used for surgical repair of larger defects in major lesions of peripheral nerves, increasing patient quality of life by saving the upper arms from amputation. PMID:24268028

  8. Histologic Characterization of Acellular Dermal Matrices in a Porcine Model of Tissue Expander Breast Reconstruction

    PubMed Central

    Carruthers, Christopher A.; Dearth, Christopher L.; Reing, Janet E.; Kramer, Caroline R.; Gagne, Darcy H.; Crapo, Peter M.; Garcia, Onelio; Badhwar, Amit; Scott, Jeffrey R.

    2015-01-01

    Background: Acellular dermal matrices (ADMs) have been commonly used in expander-based breast reconstruction to provide inferolateral prosthesis coverage. Although the clinical performance of these biologic scaffold materials varies depending on a number of factors, an in-depth systematic characterization of the host response is yet to be performed. The present study evaluates the biochemical composition and structure of two ADMs, AlloDerm® Regenerative Tissue Matrix and AlloMax™ Surgical Graft, and provides a comprehensive spatiotemporal characterization in a porcine model of tissue expander breast reconstruction. Methods: Each ADM was characterized with regard to thickness, permeability, donor nucleic acid content, (residual double-stranded DNA [dsDNA]), and growth factors (basic fibroblast growth factor [bFGF], vascular endothelial growth factor [VEGF], and transforming growth factor-beta 1 [TGF-β1]). Cytocompatibility was evaluated by in vitro cell culture on the ADMs. The host response was evaluated at 4 and 12 weeks at various locations within the ADMs using established metrics of the inflammatory and tissue remodeling response: cell infiltration, multinucleate giant cell formation, extent of ADM remodeling, and neovascularization. Results: AlloMax incorporated more readily with surrounding host tissue as measured by earlier and greater cell infiltration, fewer foreign body giant cells, and faster remodeling of ADM. These findings correlated with the in vitro composition and cytocompatibility analysis, which showed AlloMax to more readily support in vitro cell growth. Conclusions: AlloMax and AlloDerm demonstrated distinct remodeling characteristics in a porcine model of tissue expander breast reconstruction. PMID:24941900

  9. The use of an acellular collagen matrix in penile augmentation: A pilot study in Saudi Arabia

    PubMed Central

    Tealab, Alaa A.; Maarouf, Aref M.; Habous, Mohamed; Ralph, David J.; Abohashem, Safwat

    2013-01-01

    Objectives To assess the use of an acellular collagen matrix (Pelvicol, Bard Medical, Covington, GA, USA), a successful agent for reconstructive surgery, for enhancing penile girth. Patients and methods Between June and December 2011, 18 patients (mean age 24 years, range 19–38) had their penis augmented with Pelvicol; the mean (range) penile circumference was 9.2 (7–13) cm before treatment. They were divided into two groups; the first (10 patients) had a Pelvicol sheet of 8 × 12 cm inserted through a V–Y suprapubic incision and wrapped around the shaft in a bilayer under the dartos fascia, but not covering the urethra, with division of the suspensory ligament. The second group of eight patients had the Pelvicol inserted through a subcoronal degloving incision and placed in one layer. The penile circumference was measured at 6 and 12 months after surgery. Patient satisfaction at 1 year after surgery was assessed as ‘poor’, ‘unsatisfied’, ‘moderately satisfied’, ‘highly satisfied’, or ‘excellent’. Results The mean (range) increase in girth (circumference) was 2.8 (2–3.2) cm in group 1 and 1.7 (1.2–2) cm in group 2. In group 1, two patients were highly satisfied, four moderately satisfied and four unsatisfied; in group 2, three were moderately satisfied and five unsatisfied. Complications were common in both groups, with five patients in group 1 and three in group 2 developing severe penile oedema and ischaemic shaft ulcers. Removal of the graft was required in two patients in each group. Conclusion This pilot study shows that Pelvicol is not an ideal option for enhancing penile girth, and the method of placement did not apparently influence the result. PMID:26558077

  10. Clinical application of cultured epithelial autografts on acellular dermal matrices in the treatment of extended burn injuries.

    PubMed

    Fang, Taolin; Lineaweaver, William C; Sailes, Frederick C; Kisner, Carson; Zhang, Feng

    2014-11-01

    Achieving permanent replacement of skin in extensive full-thickness and deep partial-thickness burn injuries and chronic wounds remains one of the fundamental surgical problems. Presently, split-thickness skin grafts are still considered the best material for surgical repair of an excised burn wound. However, in burns that affect greater than 50% of total body surface area, the patient has insufficient areas of unaffected skin from which split-thickness skin grafts can be harvested. The use of cultured epithelial (or epidermal) autografts (CEAs) has achieved satisfactory results. But the take rate of CEAs is poor in full-thickness bed or in chronically infected area. Providing temporary cover with allograft skin, or a more permanent allodermis, may increase clinical take. This review aims to (1) describe the use of CEAs in the regeneration of the epidermis, (2) introduce the application of the acellular dermal matrices (ADMs) in the clinics, and (3) enhance understanding of the CEAs applied with ADM as an appropriate strategy to treat the extended burn injuries. The current evidence regarding the cultured epithelial cell or keratinocyte autograft and dermal grafts applied in the treatment of burn injuries was investigated with an extensive electronic and manual search (MEDLINE and EMBASE). The included literature (N=136 publications) was critically evaluated focusing on the efficacy and safety of this technique in improving the healing of the deep dermal and full-thickness burn injuries. This review concluded that the use of ADM with CEAs is becoming increasingly routine, particularly as a life-saving tool after acute thermal trauma. PMID:24322642

  11. The role of exosomes in peripheral nerve regeneration

    PubMed Central

    Ching, Rosanna C.; Kingham, Paul J.

    2015-01-01

    Peripheral nerve injuries remain problematic to treat, with poor functional recovery commonly observed. Injuries resulting in a nerve gap create specific difficulties for axonal regeneration. Approaches to address these difficulties include autologous nerve grafts (which are currently the gold standard treatment) and synthetic conduits, with the latter option being able to be impregnated with Schwann cells or stem cells which provide an appropriate micro-environment for neuronal regeneration to occur. Transplanting stem cells, however, infers additional risk of malignant transformation as well as manufacturing difficulties and ethical concerns, and the use of autologous nerve grafts and Schwann cells requires the sacrifice of a functioning nerve. A new approach utilizing exosomes, secreted extracellular vesicles, could avoid these complications. In this review, we summarize the current literature on exosomes, and suggest how they could help to improve axonal regeneration following peripheral nerve injury. PMID:26109947

  12. Extended Eden model reproduces growth of an acellular slime mold

    NASA Astrophysics Data System (ADS)

    Wagner, Geri; Halvorsrud, Ragnhild; Meakin, Paul

    1999-11-01

    A stochastic growth model was used to simulate the growth of the acellular slime mold Physarum polycephalum on substrates where the nutrients were confined in separate drops. Growth of Physarum on such substrates was previously studied experimentally and found to produce a range of different growth patterns [Phys. Rev. E 57, 941 (1998)]. The model represented the aging of cluster sites and differed from the original Eden model in that the occupation probability of perimeter sites depended on the time of occupation of adjacent cluster sites. This feature led to a bias in the selection of growth directions. A moderate degree of persistence was found to be crucial to reproduce the biological growth patterns under various conditions. Persistence in growth combined quick propagation in heterogeneous environments with a high probability of locating sources of nutrients.

  13. Protection against pertussis by acellular pertussis vaccines (Takeda, Japan): household contact studies in Kawasaki City, Japan.

    PubMed

    Kato, T; Goshima, T; Nakajima, N; Kaku, H; Arimoto, Y; Hayashi, F

    1989-12-01

    To evaluate the vaccine efficacy of an acellular pertussis vaccine which has been in clinical use in Japan since 1981, a retrospective study was performed by a questionnaire survey of secondary pertussis attacks through family contact in 146 children with pertussis diagnosed in the period from January 1981 through May 1988. In this study, acellular vaccine made by Takeda Pharmaceutical Company, which contains a high level of FHA (filamentous hemagglutinin), a low level of PT (pertussis toxin) and a small amount of agglutinogen, was evaluated. Secondary pertussis attacks through family contact were found in 17 of 29 siblings (58.6%) not immunized with pertussis vaccine. On the other hand, 27 siblings immunized with Takeda's acellular vaccine were exposed to pertussis through family contact and a secondary attack was seen in only one of them (3.7%). The present study revealed an efficacy rate of 93.7% for Takeda's acellular pertussis vaccine. PMID:2516396

  14. [Protection against pertussis by Japanese T type acellular pertussis vaccine: household contact study in Kawasaki City].

    PubMed

    Kato, T; Matsuyoshi, S; Goshima, T; Nakajima, N; Yamamoto, H; Arimoto, Y; Kaku, H; Hayashi, F

    1989-09-01

    To evaluate the vaccine efficacy of acellular pertussis vaccine which has been in clinical use in Japan since 1981, a retrospective study was made by a questionnaire from secondary pertussis attack through family contact in 149 children with pertussis diagnosed in the period from January 1981 through May 1988. In this study, Takeda's acellular vaccine which contains a high level of FHA, low level of PT and a small amount of agglutinogen, was evaluated. Secondary pertussis attacks through family contact were found in 17 of 29 siblings (58.6%) not immunized with pertussis vaccine. On the other hand of the siblings immunized with Takeda's acellular vaccine 27 were exposed to pertussis through family contact and a secondary attack was seen in only one of them (3.4%). The present study revealed an efficacy rate of 94.2% for the Takeda's acellular pertussis vaccine. PMID:2509597

  15. Protection against pertussis by Takeda's acellular pertussis vaccine: household contact studies in Kawasaki City, Japan.

    PubMed

    Kato, T; Kaku, H; Arimoto, Y

    1988-01-01

    To evaluate the vaccine efficacy of an acellular pertussis vaccine which has been in clinical use in Japan since 1981, a retrospective study was performed by a questionnaire survey of secondary pertussis attacks through family contact in 146 children with pertussis diagnosed in the period from January 1981 through May 1988. In this study, Takeda's acellular vaccine which contains a high level of FHA, low level of PT and a small amount of agglutinogen, was evaluated. Secondary pertussis attacks through family contact were found in 17 of 27 siblings (62.9%) not immunized with pertussis vaccine. On the other hand, 26 siblings immunized with Takeda's acellular vaccine were exposed to pertussis through family contact and a secondary attack was seen in only one of them (3.8%). The present study revealed an efficacy rate of 93.9% for Takeda's acellular pertussis vaccine. PMID:3078808

  16. An attenuated immune response by Schwann cells and macrophages inhibits nerve regeneration in aged rats.

    PubMed

    Scheib, Jami L; Höke, Ahmet

    2016-09-01

    Although peripheral nerves are capable of regeneration, advanced age decreases the potential for functional recovery after injury. The cellular mechanisms for this are not currently understood. Here, we performed sciatic nerve grafting with young (2 months old) and aged (18 months old) Brown-Norway male rats, in which 1 cm nerve grafts from young or aged rats were sutured into nerves of young or aged rats. Axons were allowed to regenerate until the nerve grafts and distal nerves were harvested at 1, 3, and 7 days and 2 and 6 weeks. At 6 weeks, our data suggested that young nerve grafts supported regeneration better than aged nerve grafts. In addition, myelin debris clearance was inhibited in young nerves when grafted into aged rats, but clearance was faster when aged nerves were grafted into young rats. Further analysis revealed that aged macrophages have delayed migration into injured nerve, and macrophages and Schwann cells from aged rats were less phagocytic for myelin debris in vitro. To understand these impairments, expression levels of pro- and anti-inflammatory cytokines were analyzed at 1 day after injury. Based on these levels, there was not a clear polarization to either an M1 or M2 phenotype; however, expression levels of IL-6, IL-10, CCL2 (MCP1), and Arg-1 were decreased in aged nerves. Taken together, both macrophages and Schwann cells had attenuated responses to nerve injury in aged rats, leading to inefficient clearance of debris and impaired axonal regeneration. PMID:27459920

  17. Update on nerve repair by biological tubulization

    PubMed Central

    2014-01-01

    Many surgical techniques are available for bridging peripheral nerve defects. Autologous nerve grafts are the current gold standard for most clinical conditions. In selected cases, alternative types of conduits can be used. Although most efforts are today directed towards the development of artificial synthetic nerve guides, the use of non-nervous autologous tissue-based conduits (biological tubulization) can still be considered a valuable alternative to nerve autografts. In this paper we will overview the advancements in biological tubulization of nerve defects, with either mono-component or multiple-component autotransplants, with a special focus on the use of a vein segment filled with skeletal muscle fibers, a technique that has been widely investigated in our laboratory and that has already been successfully introduced in the clinical practice. PMID:24606921

  18. Update on nerve repair by biological tubulization.

    PubMed

    Geuna, Stefano; Tos, Pierluigi; Titolo, Paolo; Ciclamini, Davide; Beningo, Teresa; Battiston, Bruno

    2014-01-01

    Many surgical techniques are available for bridging peripheral nerve defects. Autologous nerve grafts are the current gold standard for most clinical conditions. In selected cases, alternative types of conduits can be used. Although most efforts are today directed towards the development of artificial synthetic nerve guides, the use of non-nervous autologous tissue-based conduits (biological tubulization) can still be considered a valuable alternative to nerve autografts. In this paper we will overview the advancements in biological tubulization of nerve defects, with either mono-component or multiple-component autotransplants, with a special focus on the use of a vein segment filled with skeletal muscle fibers, a technique that has been widely investigated in our laboratory and that has already been successfully introduced in the clinical practice. PMID:24606921

  19. Use new PLGL-RGD-NGF nerve conduits for promoting peripheral nerve regeneration

    PubMed Central

    2012-01-01

    Background Nerve conduits provide a promising strategy for peripheral nerve injury repair. However, the efficiency of nerve conduits to enhance nerve regeneration and functional recovery is often inferior to that of autografts. Nerve conduits require additional factors such as cell adhesion molecules and neurotrophic factors to provide a more conducive microenvironment for nerve regeneration. Methods In the present study, poly{(lactic acid)-co-[(glycolic acid)-alt-(L-lysine)]} (PLGL) was modified by grafting Gly-Arg-Gly-Asp-Gly (RGD peptide) and nerve growth factor (NGF) for fabricating new PLGL-RGD-NGF nerve conduits to promote nerve regeneration and functional recovery. PLGL-RGD-NGF nerve conduits were tested in the rat sciatic nerve transection model. Rat sciatic nerves were cut off to form a 10 mm defect and repaired with the nerve conduits. All of the 32 Wistar rats were randomly divided into 4 groups: group PLGL-RGD-NGF, group PLGL-RGD, group PLGL and group autograft. At 3 months after surgery, the regenerated rat sciatic nerve was evaluated by footprint analysis, electrophysiology, and histologic assessment. Experimental data were processed using the statistical software SPSS 10.0. Results The sciatic function index value of groups PLGL-RGD-NGF and autograft was significantly higher than those of groups PLGL-RGD and PLGL. The nerve conduction velocities of groups PLGL-RGD-NGF and autograft were significantly faster than those of groups PLGL-RGD and PLGL. The regenerated nerves of groups PLGL-RGD-NGF and autograft were more mature than those of groups PLGL-RGD and PLGL. There was no significant difference between groups PLGL-RGD-NGF and autograft. Conclusions PLGL-RGD-NGF nerve conduits are more effective in regenerating nerves than both PLGL-RGD nerve conduits and PLGL nerve conduits. The effect is as good as that of an autograft. This work established the platform for further development of the use of PLGL-RGD-NGF nerve conduits for clinical nerve repair

  20. Human acellular dermal matrix allograft: A randomized, controlled human trial for the long-term evaluation of patients with extensive burns.

    PubMed

    Li, Xueyong; Meng, Xianghai; Wang, Xiaolin; Li, Yuejun; Li, Wangzhou; Lv, Xiaoxing; Xu, Xiaoli; Lei, Zhanjun; Li, Jinqing

    2015-06-01

    The potential of acellular dermal matrix (ADM) to improve cosmetic and functional outcomes has been demonstrated; however, there have been few clinical comparative studies assessing the long-term morphological, histological and functional changes after ADM placement. This study was designed to retrospectively evaluate the long-term outcomes of the cograft acellular dermal matrix with autologous thin split-thickness skin for the coverage of wounds in extensively burned patients. Thirty burn patients treated with a composite graft of ADM with autologous split-thickness skin from January 2007 to December 2009 were enrolled in this study. Another group of thirty patients who received only an autogenous split-thickness skin implant served as the control. Our study revealed that the collagen in the dermis treated with ADM were ordered, and the proportion of collagen III/I was much higher in the control group than in the ADM group. The basement membrane was prominent and continuous. Meanwhile, the VBSS (Vancouver Burn Skin Score) was used to evaluate skin quality, which shows a significant differences between the two group (P<0.001). Then the functional level was evaluated by the BI (Barthel Index), and the ADM group was much better than the control group (P=0.005). Based on these results, we concluded that the composite graft of ADM with autologous thin split-thickness skin was suitable for repairing the defects in functional areas after a burn. This technique might facilitate wound management with acceptable esthetic outcomes, good functional recovery and less scar hyperplasia at the donor site. PMID:25687834

  1. Using Eggshell Membrane as Nerve Guide Channels in Peripheral Nerve Regeneration

    PubMed Central

    Farjah, Gholam Hossein; Heshmatian, Behnam; Karimipour, Mojtaba; Saberi, Ali

    2013-01-01

    Objective(s): The aim of this study was to evaluate the final outcome of nerve regeneration across the eggsell membrane (ESM) tube conduit in comparison with autograft. Materials and Methods: Thirty adult male rats (250-300 g) were randomized into (1) ESM conduit, (2) autograft, and (3) sham surgery groups. The eggs submerged in 5% acetic acid. The decalcifying membranes were cut into four pieces, rotated over the teflon mandrel and dried at 37°C. The left sciatic nerve was surgically cut. A 10-mm nerve segment was cut and removed. In the ESM group, the proximal and distal cut ends of the sciatic nerve were telescoped into the nerve guides. In the autograft group, the 10 mm nerve segment was reversed and used as an autologous nerve graft. All animals were evaluated by sciatic functional index (SFI) and electrophysiology testing. Results: The improvement in SFI from the first to the last evalution in ESM and autograft groups were evaluated. On days 49 and 60 post-operation, the mean SFI of ESM group was significantly greater than the autograft group (P< 0.05). On day 90, the mean nerve conduction velocity (NCV) of ESM group was greater than autograft group, although the difference was not statistically significant (P> 0.05). Conclusion: These findings demonstrate that ESM effectively enhances nerve regeneration and promotes functional recovery in injured sciatic nerve of rat. PMID:24106593

  2. Effect of Delayed Peripheral Nerve Repair on Nerve Regeneration, Schwann Cell Function and Target Muscle Recovery

    PubMed Central

    Jonsson, Samuel; Wiberg, Rebecca; McGrath, Aleksandra M.; Novikov, Lev N.; Wiberg, Mikael; Novikova, Liudmila N.; Kingham, Paul J.

    2013-01-01

    Despite advances in surgical techniques for peripheral nerve repair, functional restitution remains incomplete. The timing of surgery is one factor influencing the extent of recovery but it is not yet clearly defined how long a delay may be tolerated before repair becomes futile. In this study, rats underwent sciatic nerve transection before immediate (0) or 1, 3, or 6 months delayed repair with a nerve graft. Regeneration of spinal motoneurons, 13 weeks after nerve repair, was assessed using retrograde labeling. Nerve tissue was also collected from the proximal and distal stumps and from the nerve graft, together with the medial gastrocnemius (MG) muscles. A dramatic decline in the number of regenerating motoneurons and myelinated axons in the distal nerve stump was observed in the 3- and 6-months delayed groups. After 3 months delay, the axonal number in the proximal stump increased 2–3 folds, accompanied by a smaller axonal area. RT-PCR of distal nerve segments revealed a decline in Schwann cells (SC) markers, most notably in the 3 and 6 month delayed repair samples. There was also a progressive increase in fibrosis and proteoglycan scar markers in the distal nerve with increased delayed repair time. The yield of SC isolated from the distal nerve segments progressively fell with increased delay in repair time but cultured SC from all groups proliferated at similar rates. MG muscle at 3- and 6-months delay repair showed a significant decline in weight (61% and 27% compared with contra-lateral side). Muscle fiber atrophy and changes to neuromuscular junctions were observed with increased delayed repair time suggestive of progressively impaired reinnervation. This study demonstrates that one of the main limiting factors for nerve regeneration after delayed repair is the distal stump. The critical time point after which the outcome of regeneration becomes too poor appears to be 3-months. PMID:23409189

  3. Investigation of the Regenerative Capacity of an Acellular Porcine Medial Meniscus for Tissue Engineering Applications

    PubMed Central

    Ingram, Joanne; Fisher, John; Ingham, Eileen

    2011-01-01

    Previously, we have described the development of an acellular porcine meniscal scaffold. The aims of this study were to determine the immunocompatibility of the scaffold and capacity for cellular attachment and infiltration to gain insight into its potential for meniscal repair and replacement. Porcine menisci were decellularized by exposing the tissue to freeze–thaw cycles, incubation in hypotonic tris buffer, 0.1% (w/v) sodium dodecyl sulfate in hypotonic buffer plus protease inhibitors, nucleases, hypertonic buffer followed by disinfection using 0.1% (v/v) peracetic, and final washing in phosphate-buffered saline. In vivo immunocompatibility was assessed after implantation of the acellular meniscal scaffold subcutaneously into galactosyltransferase knockout mice for 3 months in comparison to fresh and acellular tissue treated with α-galactosidase (negative control). The cellular infiltrates in the explants were assessed by histology and characterized using monoclonal antibodies against: CD3, CD4, CD34, F4/80, and C3c. Static culture was used to assess the potential of acellular porcine meniscal scaffold to support the attachment and infiltration of primary human dermal fibroblasts and primary porcine meniscal cells in vitro. The explants were surrounded by capsules that were more pronounced for the fresh meniscal tissue compared to the acellular tissues. Cellular infiltrates compromised mononuclear phagocytes, CD34-positive cells, and nonlabeled fibroblastic cells. T-lymphocytes were sparse in all explanted tissue types and there was no evidence of C3c deposition. The analysis revealed an absence of a specific immune response to all of the implanted tissues. Acellular porcine meniscus was shown to be capable of supporting the attachment and infiltration of primary human fibroblasts and primary porcine meniscal cells. In conclusion, acellular porcine meniscal tissue exhibits excellent immunocompatibility and potential for cellular regeneration in the longer

  4. Optic nerve atrophy

    MedlinePlus

    Optic nerve atrophy is damage to the optic nerve. The optic nerve carries images of what the eye sees to ... problem most often affects older adults. The optic nerve can also be damaged by shock, toxins, radiation, ...

  5. Nerve biopsy (image)

    MedlinePlus

    Nerve biopsy is the removal of a small piece of nerve for examination. Through a small incision, a sample ... is removed and examined under a microscope. Nerve biopsy may be performed to identify nerve degeneration, identify ...

  6. Peripheral Nerve Disorders

    MedlinePlus

    ... spinal cord. Like static on a telephone line, peripheral nerve disorders distort or interrupt the messages between the brain ... body. There are more than 100 kinds of peripheral nerve disorders. They can affect one nerve or many nerves. ...

  7. Second-harmonic generation microscopy for assessment of mesenchymal stem cell-seeded acellular dermal matrix in wound-healing.

    PubMed

    Wang, Qiannan; Jin, Ying; Deng, Xiaoyuan; Liu, Hanping; Pang, Hongwen; Shi, Panpan; Zhan, Zhigang

    2015-01-01

    Direct intra-skin injection of mesenchymal stem cells (MSCs) and the use of biomaterial scaffolds for grafts are both promising approaches of skin wound repair, however they still cannot generate skin that completely resembles the natural skin structures. In this study, we combined these two approaches by using acellular dermal matrix (ADM) recellularized with MSCs to repair cutaneous wounds in a murine model and two-photon fluorescence (TPF) microscopy and second-harmonic generation (SHG) microscopy to assess the effects of this therapy on wound healing. Bone marrow-derived mesenchymal stem cells (BM-MSCs) were tagged with GFP and seeded into ADM (ADM-MSC) via MSC and ADM co-culture. ADM-MSC, ADM or saline was applied to murine excisional skin wounds and wound-healing was evaluated by histological examination on days 7, 14, 21 and TFP microscopy on days 1, 3, 5 and 21 post-treatment. ADM-MSC promoted healing significantly more than treatment with ADM or saline alone, as it led to substantial neovascularization and complete skin appendage regeneration. Furthermore, the SHG microscopic imaging technique proved to be a useful tool for monitoring changes in the collagen network at the wound site during the healing process and assessing the effects of different therapies. PMID:25890761

  8. Facial Nerve Trauma: Evaluation and Considerations in Management

    PubMed Central

    Gordin, Eli; Lee, Thomas S.; Ducic, Yadranko; Arnaoutakis, Demetri

    2014-01-01

    The management of facial paralysis continues to evolve. Understanding the facial nerve anatomy and the different methods of evaluating the degree of facial nerve injury are crucial for successful management. When the facial nerve is transected, direct coaptation leads to the best outcome, followed by interpositional nerve grafting. In cases where motor end plates are still intact but a primary repair or graft is not feasible, a nerve transfer should be employed. When complete muscle atrophy has occurred, regional muscle transfer or free flap reconstruction is an option. When dynamic reanimation cannot be undertaken, static procedures offer some benefit. Adjunctive tools such as botulinum toxin injection and biofeedback can be helpful. Several new treatment modalities lie on the horizon which hold potential to alter the current treatment algorithm. PMID:25709748

  9. Surgical treatment of painful lesions of the inferior alveolar nerve.

    PubMed

    Biglioli, Federico; Allevi, Fabiana; Lozza, Alessandro

    2015-10-01

    Nerve-related complications are being reported with increasing frequency following oral and dental surgery, and typically involve the inferior alveolar nerve (IAN). We assess herein the etiology of neuropathic pain related to IAN injuries, and describe the various surgical treatment techniques available. Between 2007 and 2013, 19 patients were referred to the Maxillofacial Surgery Department of San Paolo Hospital (Milan, Italy) with pain in the area supplied by the IAN, which developed following endodontic treatment, oral surgery and maxillofacial surgery. All patients underwent IAN surgery by several different microsurgical procedures. Most of the patients affected by pain before surgery experienced complete or partial amelioration of symptoms. All patients receiving sural nerve grafts were pain-free 12 months after surgery. In five patients the operation was unsuccessful. In 78.94% of cases, a significant increase in nerve function was observed. Pain following IAN surgical damage may be addressed by microsurgery; nerve substitution with a sural nerve interpositional graft appears to represent the most efficacious procedure. Scar releasing, nerve decompression and nerve substitution using vein grafts are less effective. Removal of endodontic material extravasated into the mandibular canal is mandatory and effective in patients experiencing severe pain. Surgery should be performed within 12 months postoperatively, ideally during the first few weeks after symptoms onset. PMID:26315275

  10. In vivo effects of human adipose-derived stem cells reseeding on acellular bovine pericardium in nude mice.

    PubMed

    Wu, Qingkai; Dai, Miao; Xu, Peirong; Hou, Min; Teng, Yincheng; Feng, Jie

    2016-01-01

    Tissue-engineered biologic products may be a viable option in the reconstruction of pelvic organ prolapse (POP). This study was based on the hypothesis that human adipose-derived stem cells (hASCs) are viable in acellular bovine pericardium (ABP), when reseeded by two different techniques, and thus, aid in the reconstruction. To investigate the reseeding of hASCs on ABP grafts by using non-invasive bioluminescence imaging (BLI), and to identify the effective hASCs-scaffold combinations that enabled regeneration. Thirty female athymic nude mice were randomly divided into three groups: In the VIVO group, ABPs were implanted in the subcutaneous pockets and enhanced green fluorescent protein luciferase (eGFP·Luc)-hASCs (1 × 10(6) cells/50 µL) were injected on the ABP at the same time. In the VITRO group, the mice were implanted with grafts that ABP were co-cultured with eGFP·Luc-hASCs in vitro. The BLANK group mice were implanted with ABP only. The eGFP·Luc-hASCs reseeded on ABP were analyzed by BLI, histology, and immunohistochemistry. The eGFP·Luc-hASCs reseeded on ABP could be visualized at 12 weeks in vivo. Histology revealed that the VIVO group displayed the highest cell ingrowths, small vessels, and percent of collagen content per unit area. Desmin and α-smooth muscle actin were positive at the same site in the VIVO group cells. However, few smooth muscles were observed in the VITRO and BLANK groups. These results suggest that hASCs reseeded on ABP in vivo during surgery may further enhance the properties of ABP and may promote regeneration at the recipient site, resulting in a promising treatment option for POP. PMID:26253192

  11. Comparative biological activities of acellular pertussis vaccines produced by Kitasato.

    PubMed

    Watanabe, M; Izumiya, K; Sato, T; Yoshino, K; Nakagawa, N; Ohoishi, M; Hoshino, M

    1991-04-01

    The quality of 14 lots of acellular pertussis-diphtheria-tetanus (AC-PDT) vaccines manufactured by the Kitasato Institute during the period 1987-1990 were investigated. The geometric means of HSU, LPU, and BWDU were 0.078, 0.257, and 7.33 per ml respectively. The potency was higher than 14 IU per ml. These results indicated the consistency of the Kitasato AC-PDT vaccines. The antibody response to the AC-PDT vaccines was measured in primary and secondary vaccinated mice by ELISA. IgG antibody response to FHA and PT was obtained in all immunized mice (P less than 0.001) after the primary injection. In contrast, IgG antibody response to fimbriae 2 showed a significant titer rise (P less than 0.001) after the booster injection. The results indicated that the Kitasato AC-P vaccines consisted of protein, PT and FHA as the major antigens, and a little agglutinogen as the minor antigen. PMID:1798236

  12. [Experimental, clinical and immunologic assessment of acellular staphylococcal vaccine "Staphylovac"].

    PubMed

    Egorova, N B; Efremova, V N; Kurbatova, E A; Gruber, I M

    2008-01-01

    Results of experimental, clinical and immunological effects of acellular dry staphylococcal vaccine "Staphylovac" developed in Mechnikov Research Institute of Vaccines and Sera are presented. Original mildly virulent strains of Staphylococcus aureus having high immunogenicity, and intra- and interspecies protective activity against different representatives of opportunistic microflora were used for construction of the preparation. Low-toxicity and weak anapylactogenicity of the vaccine were established. In experiments on mice, guinea pigs and rabbits significant protective, antigenic and immunomodulate activity of the preparation was revealed with low sensitization of animals. Clinical trials performed in different centers showed that inclusion of vaccinotherapy in complex treatment of chronic staphylococcal infections (chronic pyodermia, lung abscess etc.) resulted in prolonged pathologic locus, decrease of number and severity of exacerbations, prolongation of remission, and complete recovery in significant number of patients. Activation of innate and adaptive immunity was revealed in the same patients. It was shown on the large group of athletes that administration of the vaccine by aerosol route prevents disruption of immunologic adaptation occurring due to excess physical activity and stress situations during competitions. PMID:19186558

  13. Spherical indentation of free-standing acellular extracellular matrix membranes.

    PubMed

    Cloonan, Aidan J; O'Donnell, Michael R; Lee, William T; Walsh, Michael T; De Barra, Eamonn; McGloughlin, Tim M

    2012-01-01

    Numerous scaffold materials have been developed for tissue engineering and regenerative medicine applications to replace or repair damaged tissues and organs. Naturally occurring scaffold materials derived from acellular xenogeneic and autologous extracellular matrix (ECM) are currently in clinical use. These biological scaffold materials possess inherent variations in mechanical properties. Spherical indentation or ball burst testing has commonly been used to evaluate ECM and harvested tissue due to its ease of use and simulation of physiological biaxial loading, but has been limited by complex material deformation profiles. An analytical methodology has been developed and applied to experimental load-deflection data of a model hyperelastic material and lyophilized ECM scaffolds. An optimum rehydration protocol was developed based on water absorption, hydration relaxation and dynamic mechanical analysis. The analytical methodology was compared with finite element simulations of the tests and excellent correlation was seen between the computed biaxial stress resultants and geometry deformations. A minimum rehydration period of 5 min at 37°C was sufficient for the evaluated multilaminated ECM materials. The proposed approach may be implemented for convenient comparative analysis of ECM materials and source tissues, process optimization or during lot release testing. PMID:21864728

  14. Nerve Transfers in Birth Related Brachial Plexus Injuries: Where Do We Stand?

    PubMed

    Davidge, Kristen M; Clarke, Howard M; Borschel, Gregory H

    2016-05-01

    This article reviews the assessment and management of obstetrical brachial plexus palsy. The potential role of distal nerve transfers in the treatment of infants with Erb's palsy is discussed. Current evidence for motor outcomes after traditional reconstruction via interpositional nerve grafting and extraplexal nerve transfers is reviewed and compared with the recent literature on intraplexal distal nerve transfers in obstetrical brachial plexus injury. PMID:27094890

  15. Grafted dopamine neurons: Morphology, neurochemistry, and electrophysiology.

    PubMed

    Strömberg, Ingrid; Bickford, Paula; Gerhardt, Greg A

    2010-02-01

    Grafting of dopamine-rich tissue to counteract the symptoms in Parkinson's disease became a promising tool for future treatment. This article discusses how to improve the functional outcome with respect to graft outgrowth and functions of dopamine release and electrophysiological responses to graft implantation in the host brain striatal target. It has been documented that a subpopulation of the dopamine neurons innervates the host brain in a target-specific manner, while some of the grafted dopamine neurons never project to the host striatum. Neurochemical studies have demonstrated that the graft-induced outgrowth synthesize, store, metabolize and release dopamine and possibly other neurotransmitters such as 5-HT. Furthermore, the released dopamine affects the dopamine-depleted brain in areas that are larger than the graft-derived nerve fibers reach. While stem cells will most likely be the future source of cells to be used in grafting, it is important to find the guiding cues for how to reinnervate the dopamine-depleted striatum in a proper way with respect to the dopamine subpopulations of A9 and A10 to efficiently treat the motor abnormalities seen in Parkinson's disease. PMID:19853009

  16. Unilateral Multiple Facial Nerve Branch Reconstruction Using “End-to-side Loop Graft” Supercharged by Hypoglossal Nerve

    PubMed Central

    Sasaki, Ryo; Takeuchi, Yuichi; Watanabe, Yorikatsu; Niimi, Yosuke; Sakurai, Hiroyuki; Miyata, Mariko; Yamato, Masayuki

    2014-01-01

    Background: Extensive facial nerve defects between the facial nerve trunk and its branches can be clinically reconstructed by incorporating double innervation into an end-to-side loop graft technique. This study developed a new animal model to evaluate the technique’s ability to promote nerve regeneration. Methods: Rats were divided into the intact, nonsupercharge, and supercharge groups. Artificially created facial nerve defects were reconstructed with a nerve graft, which was end-to-end sutured from proximal facial nerve stump to the mandibular branch (nonsupercharge group), or with the graft of which other end was end-to-side sutured to the hypoglossal nerve (supercharge group). And they were evaluated after 30 weeks. Results: Axonal diameter was significantly larger in the supercharge group than in the nonsupercharge group for the buccal (3.78 ± 1.68 vs 3.16 ± 1.22; P < 0.0001) and marginal mandibular branches (3.97 ± 2.31 vs 3.46 ± 1.57; P < 0.0001), but the diameter was significantly larger in the intact group for all branches except the temporal branch. In the supercharge group, compound muscle action potential amplitude was significantly higher than in the nonsupercharge group (4.18 ± 1.49 mV vs 1.87 ± 0.37 mV; P < 0.0001) and similar to that in the intact group (4.11 ± 0.68 mV). Retrograde labeling showed that the mimetic muscles were double-innervated by facial and hypoglossal nerve nuclei in the supercharge group. Conclusions: Multiple facial nerve branch reconstruction with an end-to-side loop graft was able to achieve axonal distribution. Additionally, axonal supercharge from the hypoglossal nerve significantly improved outcomes. PMID:25426357

  17. Acellular hydrogel for regenerative burn wound healing: translation from a porcine model

    PubMed Central

    Papa, Arianne; Burke, Jacqueline; Volk, Susan W; Gerecht, Sharon

    2015-01-01

    Currently available skin grafts and skin substitute for healing following third-degree burn injuries is fraught with complications, often resulting in long-term physical and psychological sequelae. Synthetic treatment that can promote wound healing in a regenerative fashion would provide an off-the-shelf, non-immunogenic strategy to improve clinical care of severe burn wounds. Here, we demonstrate vulnerary efficacy and accelerated healing mechanism of dextran-based hydrogel in third-degree porcine burn model. The model was optimized to allow examination of the hydrogel treatment for clinical translation and its regenerative response mechanisms. Hydrogel treatment accelerated third-degree burn wound healing by rapid wound closure, improved reepithelialization, enhanced extracellular matrix remodeling, and greater nerve reinnervation, compared to the dressing treated group. These effects appear to be mediated through the ability of the hydrogel to facilitate a rapid but brief initial inflammatory response that coherently stimulates neovascularization within the granulation tissue during the first week of treatment, followed by an efficient vascular regression to promote a regenerative healing process. Our results suggest that the dextran-based hydrogels may substantially improve healing quality and reduce skin grafting incidents and thus pave the way for clinical studies to improve the care of severe burn injury patients. PMID:26358387

  18. Repairing Peripheral Nerves: Is there a Role for Carbon Nanotubes?

    PubMed

    Oprych, Karen M; Whitby, Raymond L D; Mikhalovsky, Sergey V; Tomlins, Paul; Adu, Jimi

    2016-06-01

    Peripheral nerve injury continues to be a major global health problem that can result in debilitating neurological deficits and neuropathic pain. Current state-of-the-art treatment involves reforming the damaged nerve pathway using a nerve autograft. Engineered nerve repair conduits can provide an alternative to the nerve autograft avoiding the inevitable tissue damage caused at the graft donor site. Commercially available nerve repair conduits are currently only considered suitable for repairing small nerve lesions; the design and performance of engineered conduits requires significant improvements to enable their use for repairing larger nerve defects. Carbon nanotubes (CNTs) are an emerging novel material for biomedical applications currently being developed for a range of therapeutic technologies including scaffolds for engineering and interfacing with neurological tissues. CNTs possess a unique set of physicochemical properties that could be useful within nerve repair conduits. This progress report aims to evaluate and consolidate the current literature pertinent to CNTs as a biomaterial for supporting peripheral nerve regeneration. The report is presented in the context of the state-of-the-art in nerve repair conduit design; outlining how CNTs may enhance the performance of next generation peripheral nerve repair conduits. PMID:27027923

  19. Pre-differentiation of mesenchymal stromal cells in combination with a microstructured nerve guide supports peripheral nerve regeneration in the rat sciatic nerve model.

    PubMed

    Boecker, Arne Hendrik; van Neerven, Sabien Geraldine Antonia; Scheffel, Juliane; Tank, Julian; Altinova, Haktan; Seidensticker, Katrin; Deumens, Ronald; Tolba, Rene; Weis, Joachim; Brook, Gary Anthony; Pallua, Norbert; Bozkurt, Ahmet

    2016-02-01

    Many bioartificial nerve guides have been investigated pre-clinically for their nerve regeneration-supporting function, often in comparison to autologous nerve transplantation, which is still regarded as the current clinical gold standard. Enrichment of these scaffolds with cells intended to support axonal regeneration has been explored as a strategy to boost axonal regeneration across these nerve guides Ansselin et al. (1998). In the present study, 20 mm rat sciatic nerve defects were implanted with a cell-seeded microstructured collagen nerve guide (Perimaix) or an autologous nerve graft. Under the influence of seeded, pre-differentiated mesenchymal stromal cells, axons regenerated well into the Perimaix nerve guide. Myelination-related parameters, like myelin sheath thickness, benefitted from an additional seeding with pre-differentiated mesenchymal stromal cells. Furthermore, both the number of retrogradely labelled sensory neurons and the axon density within the implant were elevated in the cell-seeded scaffold group with pre-differentiated mesenchymal stromal cells. However, a pre-differentiation had no influence on functional recovery. An additional cell seeding of the Perimaix nerve guide with mesenchymal stromal cells led to an extent of functional recovery, independent of the differentiation status, similar to autologous nerve transplantation. These findings encourage further investigations on pre-differentiated mesenchymal stromal cells as a cellular support for peripheral nerve regeneration. PMID:26296589

  20. A single injection of intravitreal ranibizumab in the treatment of choroidal neovascularisation secondary to optic nerve head drusen in a child

    PubMed Central

    Alkin, Zeynep; Ozkaya, Abdullah; Yilmaz, Ihsan; Yazici, Ahmet Taylan

    2014-01-01

    Optic nerve head drusen are acellular, calcified deposits which may be found in buried or exposed drusen form. Choroidal neovascularisation secondary to optic nerve head drusen is rarely seen in childhood. This case report summarises the clinical and therapeutic outcomes of a 13-year-old girl with unilateral choroidal neovascularisation secondary to optic nerve head drusen. The patient was successfully treated with a single intravitreal ranibizumab injection. After a month from the injection the visual acuity increased dramatically and maintained at the same level during 9 months of follow-up time. There was no complication related to the injection. PMID:24792030

  1. Biomaterials for the Development of Peripheral Nerve Guidance Conduits

    PubMed Central

    Nectow, Alexander R.; Marra, Kacey G.

    2012-01-01

    Currently, surgical treatments for peripheral nerve injury are less than satisfactory. The gold standard of treatment for peripheral nerve gaps >5 mm is the autologous nerve graft; however, this treatment is associated with a variety of clinical complications, such as donor site morbidity, limited availability, nerve site mismatch, and the formation of neuromas. Despite many recent advances in the field, clinical studies implementing the use of artificial nerve guides have yielded results that are yet to surpass those of autografts. Thus, the development of a nerve guidance conduit, which could match the effectiveness of the autologous nerve graft, would be beneficial to the field of peripheral nerve surgery. Design strategies to improve surgical outcomes have included the development of biopolymers and synthetic polymers as primary scaffolds with tailored mechanical and physical properties, luminal “fillers” such as laminin and fibronectin as secondary internal scaffolds, surface micropatterning, stem cell inclusion, and controlled release of neurotrophic factors. The current article highlights approaches to peripheral nerve repair through a channel or conduit, implementing chemical and physical growth and guidance cues to direct that repair process. PMID:21812591

  2. Sciatic nerve regeneration in rats by a promising electrospun collagen/poly(ε-caprolactone) nerve conduit with tailored degradation rate

    PubMed Central

    2011-01-01

    Background To cope with the limitations faced by autograft acquisitions particularly for multiple nerve injuries, artificial nerve conduit has been introduced by researchers as a substitute for autologous nerve graft for the easy specification and availability for mass production. In order to best mimic the structures and components of autologous nerve, great efforts have been made to improve the designation of nerve conduits either from materials or fabrication techniques. Electrospinning is an easy and versatile technique that has recently been used to fabricate fibrous tissue-engineered scaffolds which have great similarity to the extracellular matrix on fiber structure. Results In this study we fabricated a collagen/poly(ε-caprolactone) (collagen/PCL) fibrous scaffold by electrospinning and explored its application as nerve guide substrate or conduit in vitro and in vivo. Material characterizations showed this electrospun composite material which was made of submicron fibers possessed good hydrophilicity and flexibility. In vitro study indicated electrospun collagen/PCL fibrous meshes promoted Schwann cell adhesion, elongation and proliferation. In vivo test showed electrospun collagen/PCL porous nerve conduits successfully supported nerve regeneration through an 8 mm sciatic nerve gap in adult rats, achieving similar electrophysiological and muscle reinnervation results as autografts. Although regenerated nerve fibers were still in a pre-mature stage 4 months postoperatively, the implanted collagen/PCL nerve conduits facilitated more axons regenerating through the conduit lumen and gradually degraded which well matched the nerve regeneration rate. Conclusions All the results demonstrated this collagen/PCL nerve conduit with tailored degradation rate fabricated by electrospinning could be an efficient alternative to autograft for peripheral nerve regeneration research. Due to its advantage of high surface area for cell attachment, it is believed that this

  3. Biological and Electrophysiologic Effects of Poly(3,4-ethylenedioxythiophene) on Regenerating Peripheral Nerve Fibers

    PubMed Central

    Baghmanli, Ziya; Sugg, Kristoffer B.; Wei, Benjamin; Shim, Bong S.; Martin, David C.; Cederna, Paul S.; Urbanchek, Melanie G.

    2014-01-01

    Background Uninjured peripheral nerves in upper-limb amputees represent attractive sites for connectivity with neuroprostheses because their predictable internal topography allows for precise sorting of motor and sensory signals. The inclusion of poly(3,4-ethylenedioxythiophene) reduces impedance and improves charge transfer at the biotic-abiotic interface. This study evaluates the in vivo performance of poly(3,4-ethylenedioxythiophene)–coated interpositional decellularized nerve grafts across a critical nerve conduction gap, and examines the long-term effects of two different poly(3,4-ethylenedioxythiophene) formulations on regenerating peripheral nerve fibers. Methods In 48 rats, a 15-mm gap in the common peroneal nerve was repaired using a nerve graft of equivalent length, including (1) decellularized nerve chemically polymerized with poly(3,4-ethylenedioxythiophene) (dry); (2) decellularized nerve electrochemically polymerized with poly(3,4-ethylenedioxythiophene) (wet); (3) intact nerve; (4) autogenous nerve graft; (5) decellularized nerve alone; and (6) unrepaired nerve gap controls. All groups underwent electrophysiologic characterization at 3 months, and nerves were harvested for histomorphometric analysis. Results Conduction velocity was significantly faster in the dry poly(3,4-ethylenedioxythiophene) group compared with the sham, decellularized nerve, and wet poly(3,4-ethylenedioxythiophene) groups. Maximum specific force for the dry poly(3,4-ethylenedioxythiophene) group was more similar to sham than were decellularized nerve controls. Evident neural regeneration was demonstrated in both dry and wet poly(3,4-ethylenedioxythiophene) groups by the presence of normal regenerating axons on histologic cross-section. Conclusions Both poly(3,4-ethylenedioxythiophene) formulations were compatible with peripheral nerve regeneration at 3 months. This study supports poly(3,4-ethylenedioxythiophene) as a promising adjunct for peripheral nerve interfaces for

  4. [Pertussis vaccines: acellular versus whole cell. Perhaps a return to the past?].

    PubMed

    Cofré, José

    2015-10-01

    The resurgence of pertussis in the world and in our country has questioned the effectiveness of cellular and acellular vaccines. The reason why pertussis has not been controlled or eliminated after 70 years of implementation of the vaccination is probably multifactorial. This article, on the basis of questions and answers, describes the benefits and limitations of both cellular and acellular vaccines and suggests new strategies of vaccination in childhood. It is a fact that the currently applied vaccination does not eliminate the circulation of Bordetella pertussis in the community. Perhaps the introduction of vaccines with live B. pertussis, inhalation, will be able to eliminate the disease around the world. PMID:26633113

  5. Controlled Delivery of FK506 to Improve Nerve Regeneration.

    PubMed

    Labroo, Pratima; Ho, Scott; Sant, Himanshu; Shea, Jill; Gale, Bruce K; Agarwal, Jay

    2016-09-01

    Autologous nerve grafts are the current "gold standard" for repair of large nerve gaps. However, they cause morbidity at the donor nerve site, only a limited amount of nerve can be harvested, and there is the potential for mismatches in size and fascicular patterns between the nerve stumps and the graft. Nerve conduits are a promising alternative to autografts and can act as guidance cues for the regenerating axons and allow for tension free bridging, without the need to harvest donor nerve. Separately, FK506, and FDA-approved small molecule, has been shown to enhance axon growth and peripheral nerve regeneration. This article describes the design of a novel drug delivery apparatus integrated with a poly lactic-co-glycolic acid (PLGA)-based nerve guide conduit for controlled local delivery of FK506. An FK506 dosage curve was acquired to determine the minimum in vitro concentration for optimal axonal outgrowth of dorsal root ganglion (DRG) cells, then PLGA devices were designed and tested in a diffusion chamber, and finally the bioactivity of the released media was evaluated by measuring axon growth in DRG cells exposed to the media for 72 h. The combined drug delivery nerve guide was able to release FK506 for 20 days at concentrations (1-20 ng/mL) that were shown to enhance DRG axon growth. Furthermore, the released FK506 was bioactive and able to enhance DRG axon growth. The combined drug delivery nerve guide can release FK506 for extended periods of time and enhance axon growth, and has the potential to improve nerve regeneration after a peripheral nerve injury. PMID:27058050

  6. Effects of motor and sensory nerve transplants on amount and specificity of sciatic nerve regeneration.

    PubMed

    Lago, Natalia; Rodríguez, Francisco J; Guzmán, Mónica S; Jaramillo, Jéssica; Navarro, Xavier

    2007-09-01

    Nerve regeneration after complete transection does not allow for adequate functional recovery mainly because of lack of selectivity of target reinnervation. We assessed if transplanting a nerve segment from either motor or sensory origin may improve specifically the accuracy of sensory and motor reinnervation. For this purpose, the rat sciatic nerve was transected and repaired with a silicone guide containing a predegenerated segment of ventral root (VR) or dorsal root (DR), compared to a silicone guide filled with saline. Nerve regeneration and reinnervation was assessed during 3 months by electrophysiologic and functional tests, and by nerve morphology and immunohistochemistry against choline acetyltransferase (ChAT) for labeling motor axons. Functional tests showed that reinnervation was successful in all the rats. However, the two groups with a root allotransplant reached higher degrees of reinnervation in comparison with the control group. Group VR showed the highest reinnervation of muscle targets, whereas Group DR had higher levels of sensory reinnervation than VR and saline groups. The total number of regenerated myelinated fibers was similar in the three groups, but the number of ChAT+ fibers was slightly lower in the VR group in comparison with DR and saline groups. These results indicate that a predegenerated root nerve allotransplant enhances axonal regeneration, leading to faster and higher levels of functional recovery. Although there is not clear preferential reinnervation, regeneration of motor axons is promoted at early times by a motor graft, whereas reinnervation of sensory pathways is increased by a sensory graft. PMID:17455293

  7. Multifunctional Silk Nerve Guides for Axon Outgrowth

    NASA Astrophysics Data System (ADS)

    Tupaj, Marie C.

    Peripheral nerve regeneration is a critical issue as 2.8% of trauma patients present with this type of injury, estimating a total of 200,000 nerve repair procedures yearly in the United States. While the peripheral nervous system exhibits slow regeneration, at a rate of 0.5 mm -- 9 mm/day following trauma, this regenerative ability is only possible under certain conditions. Clinical repairs have changed slightly in the last 30 years and standard methods of treatment include suturing damaged nerve ends, allografting, and autografting, with the autograft the gold standard of these approaches. Unfortunately, the use of autografts requires a second surgery and there is a shortage of nerves available for grafting. Allografts are a second option however allografts have lower success rates and are accompanied by the need of immunosuppressant drugs. Recently there has been a focus on developing nerve guides as an "off the shelf" approach. Although some natural and synthetic guidance channels have been approved by the FDA, these nerve guides are unfunctionalized and repair only short gaps, less than 3 cm in length. The goal of this project was to identify strategies for functionalizing peripheral nerve conduits for the outgrowth of neuron axons in vitro . To accomplish this, two strategies (bioelectrical and biophysical) were indentified for increasing axon outgrowth and promoting axon guidance. Bioelectrical strategies exploited electrical stimulation for increasing neurite outgrowth. Biophysical strategies tested a range of surface topographies for axon guidance. Novel methods were developed for integrating electrical and biophysical strategies into silk films in 2D. Finally, a functionalized nerve conduit system was developed that integrated all strategies for the purpose of attaching, elongating, and guiding nervous tissue in vitro. Future directions of this work include silk conduit translation into a rat sciatic nerve model in vivo for the purpose of repairing long

  8. Fabrication and Short-Term in Vivo Performance of a Natural Elastic Lamina-Polymeric Hybrid Vascular Graft.

    PubMed

    McCarthy, Connor W; Ahrens, Danielle C; Joda, David; Curtis, Tyler E; Bowen, Patrick K; Guillory, Roger J; Liu, Shu Q; Zhao, Feng; Frost, Megan C; Goldman, Jeremy

    2015-08-01

    Although significant advances have been made in the development of artificial vascular grafts, small-diameter grafts still suffer from excessive platelet activation, thrombus formation, smooth muscle cell intimal hyperplasia, and high occurrences of restenosis. Recent discoveries demonstrating the excellent blood-contacting properties of the natural elastic lamina have raised the possibility that an acellular elastic lamina could effectively serve as a patent blood-contacting surface in engineered vascular grafts. However, the elastic lamina alone lacks the requisite mechanical properties to function as a viable vascular graft. Here, we have screened a wide range of biodegradable and biostable medical-grade polymers for their ability to adhere to the outer surface of the elastic lamina and allow cellular repopulation following engraftment in the rat abdominal aorta. We demonstrate a novel method for the fabrication of elastic lamina-polymeric hybrid small-diameter vascular grafts and identify poly(ether urethane) (PEU 1074A) as ideal for this purpose. In vivo results demonstrate graft patency over 21 days, with low thrombus formation, mild inflammation, and the general absence of smooth muscle cell hyperplasia on the graft's luminal surface. The results provide a new direction for developing small-diameter vascular grafts that are mass-producible, shelf-stable, and universally compatible due to a lack of immune response and inhibit the in-graft restenosis response that is common to nonautologous materials. PMID:26204095

  9. Immunogenicity and safety of a monovalent, multicomponent acellular pertussis vaccine in 15 month-6-year-old German children. Monovalent Acellular Pertussis Vaccine Study Group.

    PubMed

    Stehr, K; Heininger, U; Uhlenbusch, R; Angersbach, P; Hackell, J; Eckhardt, T

    1995-03-01

    Immunization against pertussis has been re-recommended for healthy children in Germany in 1991. In addition the former restriction of immunizing only in the first 2 years of life was abolished. In children born before 1991 immunization rates against pertussis were 15% or less. With the new recommendations physicians are now faced with an increasing demand of parents for catch-up vaccinations in these children. Since they were immunized against diphtheria and tetanus previously monovalent pertussis vaccines are needed for this indication. Therefore a monovalent, multicomponent acellular pertussis vaccine was studied in 249 German children 15 months to 6 years of age. Three doses were administered at 6-10 week intervals. Reactogenicity and antibody responses against the vaccine antigens pertussis toxin (PT), filamentous haemagglutinin (FHA), 69-kd antigen (pertactin) and fimbriae-2 (agglutinogen) were investigated. Local and systemic reactions were minimal in frequency and severity. Antibody responses against all vaccine antigens were pronounced with 93%-100% of vaccinees demonstrating at least four fold titre rises above pre-immunization after the third dose. These findings indicate that this monovalent, multicomponent acellular pertussis vaccine with excellent immunogenicity and low reactogenicity is an appropriate candidate for closing immunization gaps in older children in countries with previously low vaccination rates against pertussis. Based on the results of this study the monovalent acellular pertussis vaccine was licensed in Germany in January 1994. PMID:7758519

  10. Causes of Secondary Radial Nerve Palsy and Results of Treatment.

    PubMed

    Reichert, Pawel; Wnukiewicz, Witold; Witkowski, Jarosław; Bocheńska, Aneta; Mizia, Sylwia; Gosk, Jerzy; Zimmer, Krzysztof

    2016-01-01

    BACKGROUND The aim of this study was to analyze the causes that lead to secondary damage of the radial nerve and to discuss the results of reconstructive treatment. MATERIAL AND METHODS The study group consisted of 33 patients treated for radial nerve palsy after humeral fractures. Patients were diagnosed based on clinical examinations, ultrasonography, electromyography, or nerve conduction velocity. During each operation, the location and type of nerve damage were analyzed. During the reconstructive treatment, neurolysis, direct neurorrhaphy, or reconstruction with a sural nerve graft was used. The outcomes were evaluated using the Medical Research Council (MRC) scales and the quick DASH score. RESULTS Secondary radial nerve palsy occurs after open reduction and internal fixation (ORIF) by plate, as well as by closed reduction and internal fixation (CRIF) by nail. In the case of ORIF, it most often occurs when the lateral approach is used, as in the case of CRIF with an insertion interlocking screws. The results of the surgical treatment were statistically significant and depended on the time between nerve injury and revision (reconstruction) surgery, type of damage to the radial nerve, surgery treatment, and type of fixation. Treatment results were not statistically significant, depending on the type of fracture or location of the nerve injury. CONCLUSIONS The potential risk of radial nerve neurotmesis justifies an operative intervention to treat neurological complications after a humeral fracture. Adequate surgical treatment in many of these cases allows for functional recovery of the radial nerve. PMID:26895570

  11. Handcrafted multilayer PDMS microchannel scaffolds for peripheral nerve regeneration.

    PubMed

    Hossain, Ridwan; Kim, Bongkyun; Pankratz, Rachel; Ajam, Ali; Park, Sungreol; Biswal, Sibani L; Choi, Yoonsu

    2015-12-01

    Injuries that result in the loss of limb functionality may be caused by the severing of the peripheral nerves within the affected limb. Several bioengineered peripheral nerve scaffolds have been developed in order to provide the physical support and topographical guidance necessary for the naturally disorganized axon outgrowth to reattach to distal nerve stumps as an alternative to other procedures, like nerve grafting. PDMS has been chosen for the base material of the scaffolds due to its biocompatibility, flexibility, transparency, and well-developed fabrication techniques. The process of observing the axon outgrowth across the nerve gaps with PDMS scaffolds has been challenging due to the limited number and fineness of longitudinal sections that can be extracted from harvested nerve tissue samples after implantation. To address this, multilayer microchannel scaffolds were developed with the object of providing more refined longitudinal observation of axon outgrowth by longitudinally 'sectioning' the device during fabrication, removing the need for much of the sample preparation process. This device was then implanted into the sciatic nerves of Lewis rats, and then harvested after two and four weeks to analyze the difference in nerve regeneration between two different time periods. The present layer by layer structure, which is separable after nerve regeneration and is treated as an individual layer during the histology process, provides the details of biological events during axonal regeneration. Confocal microscopic imaging showed the details of peripheral nerve regeneration including nerve branches and growth cones observable from within the microchannels of the multilayer PDMS microchannel scaffolds. PMID:26494637

  12. Causes of Secondary Radial Nerve Palsy and Results of Treatment

    PubMed Central

    Reichert, Paweł; Wnukiewicz, Witold; Witkowski, Jarosław; Bocheńska, Aneta; Mizia, Sylwia; Gosk, Jerzy; Zimmer, Krzysztof

    2016-01-01

    Background The aim of this study was to analyze the causes that lead to secondary damage of the radial nerve and to discuss the results of reconstructive treatment. Material/Methods The study group consisted of 33 patients treated for radial nerve palsy after humeral fractures. Patients were diagnosed based on clinical examinations, ultrasonography, electromyography, or nerve conduction velocity. During each operation, the location and type of nerve damage were analyzed. During the reconstructive treatment, neurolysis, direct neurorrhaphy, or reconstruction with a sural nerve graft was used. The outcomes were evaluated using the Medical Research Council (MRC) scales and the quick DASH score. Results Secondary radial nerve palsy occurs after open reduction and internal fixation (ORIF) by plate, as well as by closed reduction and internal fixation (CRIF) by nail. In the case of ORIF, it most often occurs when the lateral approach is used, as in the case of CRIF with an insertion interlocking screws. The results of the surgical treatment were statistically significant and depended on the time between nerve injury and revision (reconstruction) surgery, type of damage to the radial nerve, surgery treatment, and type of fixation. Treatment results were not statistically significant, depending on the type of fracture or location of the nerve injury. Conclusions The potential risk of radial nerve neurotmesis justifies an operative intervention to treat neurological complications after a humeral fracture. Adequate surgical treatment in many of these cases allows for functional recovery of the radial nerve. PMID:26895570

  13. A Biosynthetic Nerve Guide Conduit Based on Silk/SWNT/Fibronectin Nanocomposite for Peripheral Nerve Regeneration

    PubMed Central

    Mottaghitalab, Fatemeh; Farokhi, Mehdi; Zaminy, Arash; Kokabi, Mehrdad; Soleimani, Masoud; Mirahmadi, Fereshteh

    2013-01-01

    As a contribution to the functionality of nerve guide conduits (NGCs) in nerve tissue engineering, here we report a conduit processing technique through introduction and evaluation of topographical, physical and chemical cues. Porous structure of NGCs based on freeze-dried silk/single walled carbon nanotubes (SF/SWNTs) has shown a uniform chemical and physical structure with suitable electrical conductivity. Moreover, fibronectin (FN) containing nanofibers within the structure of SF/SWNT conduits produced through electrospinning process have shown aligned fashion with appropriate porosity and diameter. Moreover, fibronectin remained its bioactivity and influenced the adhesion and growth of U373 cell lines. The conduits were then implanted to 10 mm left sciatic nerve defects in rats. The histological assessment has shown that nerve regeneration has taken places in proximal region of implanted nerve after 5 weeks following surgery. Furthermore, nerve conduction velocities (NCV) and more myelinated axons were observed in SF/SWNT and SF/SWNT/FN groups after 5 weeks post implantation, indicating a functional recovery for the injured nerves. With immunohistochemistry, the higher S-100 expression of Schwann cells in SF/SWNT/FN conduits in comparison to other groups was confirmed. In conclusion, an oriented conduit of biocompatible SF/SWNT/FN has been fabricated with acceptable structure that is particularly applicable in nerve grafts. PMID:24098649

  14. 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

  15. Vascular replacement using a layered elastin-collagen vascular graft in a porcine model: one week patency versus one month occlusion.

    PubMed

    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

    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

  16. Nerve conduction velocity

    MedlinePlus

    Nerve conduction velocity (NCV) is a test to see how fast electrical signals move through a nerve. ... normal body temperature. Being too cold slows nerve conduction. Tell your doctor if you have a cardiac ...

  17. Femoral nerve damage (image)

    MedlinePlus

    The femoral nerve is located in the leg and supplies the muscles that assist help straighten the leg. It supplies sensation ... leg. One risk of damage to the femoral nerve is pelvic fracture. Symptoms of femoral nerve damage ...

  18. Ulnar nerve damage (image)

    MedlinePlus

    The ulnar nerve originates from the brachial plexus and travels down arm. The nerve is commonly injured at the elbow because of elbow fracture or dislocation. The ulnar nerve is near the surface of the body where ...

  19. Diabetes and nerve damage

    MedlinePlus

    ... hot or cold When the nerves that control digestion are affected, you may have trouble digesting food. ... harder to control. Damage to nerves that control digestion almost always occurs in people with severe nerve ...

  20. Efficient bridging of 20 mm rat sciatic nerve lesions with a longitudinally micro-structured collagen scaffold.

    PubMed

    Bozkurt, A; Boecker, A; Tank, J; Altinova, H; Deumens, R; Dabhi, C; Tolba, R; Weis, J; Brook, G A; Pallua, N; van Neerven, S G A

    2016-01-01

    An increasing number of biomaterial nerve guides has been developed that await direct comparative testing with the 'gold-standard' autologous nerve graft in functional repair of peripheral nerve defects. In the present study, 20 mm rat sciatic nerve defects were bridged with either a collagen-based micro-structured nerve guide (Perimaix) or an autologous nerve graft. Axons regenerated well into the Perimaix scaffold and, the majority of these axons grew across the 20 mm defect into the distal nerve segment. In fact, both the total axon number and the number of retrogradely traced somatosensory and motor neurons extending their axons across the implant was similar between Perimaix and autologous nerve graft groups. Implantation of Schwann cell-seeded Perimaix scaffolds provided only a beneficial effect on myelination within the scaffold. Functional recovery supported by the implanted, non-seeded Perimaix scaffold was as good as that observed after the autologous nerve graft, despite the presence of thinner myelin sheaths in the Perimaix implanted nerves. These findings support the potential of the Perimaix collagen scaffold as a future off-the-shelf device for clinical applications in selected cases of traumatic peripheral nerve injury. PMID:26496383

  1. Cooperative roles of BDNF expression in neurons and Schwann cells are modulated by exercise to facilitate nerve regeneration

    PubMed Central

    Wilhelm, Jennifer C.; Xu, Mei; Cucoranu, Delia; Chmielewski, Sarah; Holmes, Tiffany; Lau, Kelly (Shukkwan); Bassell, Gary J.; English, Arthur W.

    2012-01-01

    After peripheral nerve injury, neurotrophins play a key role in the regeneration of damaged axons which can be augmented by exercise, although the distinct roles played by neurons and Schwann cells are unclear. In this study, we evaluated the requirement for the neurotrophin, brain derived neurotrophic factor (BDNF), in neurons and Schwann cells, for the regeneration of peripheral axons after injury. Common fibular or tibial nerves in thy-1-YFP-H mice were cut bilaterally and repaired using a graft of the same nerve from transgenic mice lacking BDNF in Schwann cells (BDNF-/-) or wild-type mice (WT). Two weeks post-repair, axonal regeneration into BDNF-/- grafts were markedly less than WT grafts, emphasizing the importance of Schwann cell BDNF. Nerve regeneration was enhanced by treadmill training post-transection, regardless of the BDNF content of the nerve graft. We further tested the hypothesis that training-induced increases in BDNF in neurons allow regenerating axons to overcome a lack of BDNF expression in cells in the pathway through which they regenerate. Nerves in mice lacking BDNF in YFP+ neurons (SLICK) were cut and repaired with BDNF-/- and WT nerves. SLICK axons lacking BDNF did not regenerate into grafts lacking Schwann cell BDNF. Treadmill training could not rescue the regeneration into BDNF-/- grafts if the neurons also lacked BDNF. Both Schwann cell- and neuron-derived BDNF are thus important for axon regeneration in cut peripheral nerves. PMID:22492055

  2. Design and Synthesis of an Artificial Pulmonary Pleura for High Throughput Studies in Acellular Human Lungs

    PubMed Central

    Wagner, Darcy E.; Fenn, Spencer L.; Bonenfant, Nicholas R.; Marks, Elliot R.; Borg, Zachary; Saunders, Patrick; Oldinski, Rachael A.; Weiss, Daniel J.

    2015-01-01

    Whole organ decellularization of complex organs, such as lungs, presents a unique opportunity for use of acellular scaffolds for ex vivo tissue engineering or for studying cell-extracellular matrix interactions ex vivo. A growing body of literature investigating decellularizing and recellularizing rodent lungs has provided important proof of concept models and rodent lungs are readily available for high throughput studies. In contrast, comparable progress in large animal and human lungs has been impeded owing to more limited availability and difficulties in handling larger tissue. While the use of smaller segments of acellular large animal or human lungs would maximize usage from a single lung, excision of small acellular segments compromises the integrity of the pleural layer, leaving the terminal ends of blood vessels and airways exposed. We have developed a novel pleural coating using non-toxic ionically crosslinked alginate or photocrosslinked methacrylated alginate which can be applied to excised acellular lung segments, permits inflation of small segments, and significantly enhances retention of cells inoculated through cannulated airways or blood vessels. Further, photocrosslinking methacrylated alginate, using eosin Y and triethanolamine (TEOA) at 530nm wavelength, results in a mechanically stable pleural coating that permits effective cyclic 3-dimensional stretch, i.e. mechanical ventilation, of individual segments. PMID:25750684

  3. Corneal Stroma Regeneration with Acellular Corneal Stroma Sheets and Keratocytes in a Rabbit Model

    PubMed Central

    Ma, Xiao Yun; Zhang, Yun; Zhu, Dan; Lu, Yang; Zhou, Guangdong; Liu, Wei; Cao, Yilin; Zhang, Wen Jie

    2015-01-01

    Acellular corneal stroma matrix has been used for corneal stroma engineering. However, because of its compact tissue structure, regrowth of keratocytes into the scaffold is difficult. Previously, we developed a sandwich model for cartilage engineering using acellular cartilage sheets. In the present study, we tested this model for corneal stroma regeneration using acellular porcine corneal stroma (APCS) sheets and keratocytes. Porcine corneas were decellularized by NaCl treatment, and the APCS was cut into 20-μm-thick sheets. A rabbit corneal stroma defect model was created by lamellar keratoplasty and repaired by transplantation of five pieces of APCS sheets with keratocytes. Six months after transplantation, transparent corneas were present in the experimental group, which were confirmed by anterior segment optical coherence tomography examination and transmittance examination. The biomechanical properties in the experimental group were similar to those of normal cornea. Histological analyses showed an even distribution of keratocytes and well-oriented matrix in the stroma layer in the experimental group. Together, these results demonstrated that the sandwich model using acellular corneal stroma sheets and keratocytes could be potentially useful for corneal stroma regeneration. PMID:26167895

  4. Repair of a Gingival Fenestration Using an Acellular Dermal Matrix Allograft.

    PubMed

    Breault, Lawrence G; Brentson, Raquel C; Fowler, Edward B; Bisch, Frederick C

    2016-01-01

    A case report illustrating the successful treatment of a gingival fenestration with an acellular dermal matrix (ADM) allograft. After 2½ months of healing, the ADM was completely integrated into the soft tissues of the mandibular anterior gingiva with complete resolution of the gingival fenestration, resulting in excellent gingival esthetics. PMID:26874103

  5. Electrophysiological Assessment of Injury to the Infra-patellar Branch(es) of the Saphenous Nerve during Anterior Cruciate Ligament Reconstruction Using Medial Hamstring Auto-grafts: Vertical versus Oblique Harvest Site Incisions

    PubMed Central

    Tavakoli Darestani, Reza; Bagherian Lemraski, Mohammad Mehdi; Hosseinpour, Mehrdad; Kamrani-Rad, Amin

    2013-01-01

    Background It was suggested that the direction of incision for medial hamstring tendons harvesting influences the incidence of injury to the infrapatellar branch of the saphenous nerve (IPBSN), a common complication following arthroscopically-assisted anterior cruciate ligament reconstruction (ACLR). Objectives The main purpose of current study was to compare the incidence of IPBSN injury between vertical and oblique incisions utilizing electrophysiological evaluation. Patients and Methods There were 60 patients underwent arthroscopically-assisted ACLR assigned to two equal vertical or oblique incision groups, randomly. One year postoperatively, the patients were electrophysiologically examined to detect whether IPBSN is injured. The Lysholm score was completed. The patients' satisfaction with surgical outcomes determined utilizing visual analogue scale (VAS). Finally, two groups were compared and the effect of IPBSN injury on function and satisfaction was investigated. Results The incidence of IPBSN injury was higher in the vertical group (4 patients vs. 10 patients), but the difference was not statistically significant. The mean of Lysholm and VAS scores were the same. Also, the mean of Lysholm score was the same in patients with and without IPBSN injury. However, patients without IPBSN injury were more satisfied (8.9 ± 9 vs. 7.4 ± 1.1; P < 0.001). Conclusions IPBSN injury is a common complication following arthroscopically-assisted ACLR and, if not significant, oblique direction of the incision is associated with decreased incidence of the injury. IPBSN injury has no effect on the function but because of the disturbance with patients' satisfaction, authors believe the oblique incision is preferable to avoid the nerve injury during medial hamstring tendons harvesting. PMID:24693521

  6. A new technique for hypoglossal-facial nerve repair.

    PubMed

    Atlas, M D; Lowinger, D S

    1997-07-01

    Hypoglossal reinnervation of the facial nerve may be required after a proximal facial nerve injury. The classic hypoglossal-facial graft procedure involves transection of the donor hypoglossal nerve, resulting in hemiglottic paralysis that, in association with paralysis of other cranial nerves, may cause speech and swallowing difficulties. Multiple lower cranial nerve palsies in conjunction with facial paralysis, as may occur after procedures such as skull base surgery, contraindicate the use of such techniques. The successful use of XII-VII "interposition jump grafts" without hemiglossal weakness has been described However, a prolonged recovery period and weaker facial reanimation have been seen. In order to attain maximum facial reinnervation while preserving hypoglossal function, we have developed a new technique of XII-VII repair. This method involves mobilization of the intratemporal portion of the facial nerve remnant, achieving a single anastomosis with the hypoglossal nerve, which has been partially incised. This technique has been used in three patients to date, with 6 to 11 months follow-up. In all cases facial tone and symmetry have been restored and voluntary facial expression accomplished. The authors conclude that by employing the techniques described highly satisfactory cosmetic and functional results may be expected, without compromising hypoglossal nerve function. PMID:9217143

  7. 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.

  8. Effects of the decellularization method on the local stiffness of acellular lungs.

    PubMed

    Melo, Esther; Garreta, Elena; Luque, Tomas; Cortiella, Joaquin; Nichols, Joan; Navajas, Daniel; Farré, Ramon

    2014-05-01

    Lung bioengineering, a novel approach to obtain organs potentially available for transplantation, is based on decellularizing donor lungs and seeding natural scaffolds with stem cells. Various physicochemical protocols have been used to decellularize lungs, and their performance has been evaluated in terms of efficient decellularization and matrix preservation. No data are available, however, on the effect of different decellularization procedures on the local stiffness of the acellular lung. This information is important since stem cells directly sense the rigidity of the local site they are engrafting to during recellularization, and it has been shown that substrate stiffness modulates cell fate into different phenotypes. The aim of this study was to assess the effects of the decellularization procedure on the inhomogeneous local stiffness of the acellular lung on five different sites: alveolar septa, alveolar junctions, pleura, and vessels' tunica intima and tunica adventitia. Local matrix stiffness was measured by computing Young's modulus with atomic force microscopy after decellularizing the lungs of 36 healthy rats (Sprague-Dawley, male, 250-300 g) with four different protocols with/without perfusion through the lung circulatory system and using two different detergents (sodium dodecyl sulfate [SDS] and 3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate [CHAPS]). The local stiffness of the acellular lung matrix significantly depended on the site within the matrix (p<0.001), ranging from ∼ 15 kPa at the alveolar septum to ∼ 60 kPa at the tunica intima. Acellular lung stiffness (p=0.003) depended significantly, albeit modestly, on the decellularization process. Whereas perfusion did not induce any significant differences in stiffness, the use of CHAPS resulted in a ∼ 35% reduction compared with SDS, the influence of the detergent being more important in the tunica intima. In conclusion, lung matrix stiffness is considerably inhomogeneous, and

  9. Development and Characterization of Acellular Porcine Pulmonary Valve Scaffolds for Tissue Engineering

    PubMed Central

    Korossis, Sotirios A.; Wilshaw, Stacy-Paul; Jennings, Louise M; Fisher, John; Ingham, Eileen

    2014-01-01

    Currently available replacement heart valves all have limitations. This study aimed to produce and characterize an acellular, biocompatible porcine pulmonary root conduit for reconstruction of the right ventricular outflow tract e.g., during Ross procedure. A process for the decellularization of porcine pulmonary roots was developed incorporating trypsin treatment of the adventitial surface of the scraped pulmonary artery and sequential treatment with hypotonic Tris buffer (HTB; 10 mM Tris pH 8.0, 0.1% (w/v) EDTA, and 10 KIU aprotinin), 0.1% (w/v) sodium dodecyl sulfate in HTB, two cycles of DNase and RNase, and sterilization with 0.1% (v/v) peracetic acid. Histology confirmed an absence of cells and retention of the gross histoarchitecture. Immunohistochemistry further confirmed cell removal and partial retention of the extracellular matrix, but a loss of collagen type IV. DNA levels were reduced by more than 96% throughout all regions of the acellular tissue and no functional genes were detected using polymerase chain reaction. Total collagen levels were retained but there was a significant loss of glycosaminoglycans following decellularization. The biomechanical, hydrodynamic, and leaflet kinematics properties were minimally affected by the process. Both immunohistochemical labeling and antibody absorption assay confirmed a lack of α-gal epitopes in the acellular porcine pulmonary roots and in vitro biocompatibility studies indicated that acellular leaflets and pulmonary arteries were not cytotoxic. Overall the acellular porcine pulmonary roots have excellent potential for development of a tissue substitute for right ventricular outflow tract reconstruction e.g., during the Ross procedure. PMID:24786313

  10. Behavioural and anatomical analysis of selective tibial nerve branch transfer to the deep peroneal nerve in the rat.

    PubMed

    Kemp, Stephen W P; Alant, Jacob; Walsh, Sarah K; Webb, Aubrey A; Midha, Rajiv

    2010-03-01

    Nerve transfer procedures involving the repair of a distal denervated nerve element with that of a foreign proximal nerve have become increasingly popular for clinical nerve repair as a surgical alternative to autologous nerve grafting. However, the functional outcomes and the central plasticity for these procedures remain poorly defined, particularly for a clinically relevant rodent model of hindlimb nerve transfer. We therefore evaluated the effect of selective tibial branch nerve transfer on behavioural recovery in animals following acute transection of the deep peroneal nerve. The results indicate that not only can hindlimb nerve transfers be successfully accomplished in a rat model but that these animals display a return of skilled locomotor function on a par with animals that underwent direct deep peroneal nerve repair (the current gold standard). At 2 months, ground reaction force analysis demonstrated that partial restoration of braking forces occurred in the nerve transfer group, whereas the direct repair group had fully restored these forces to similar to baseline levels. Ankle kinematic analysis revealed that only animals in the direct repair group significantly recovered flexion during the step cycle, indicating a recovery of surgically induced foot drop. Terminal electrophysiological and myological assessments demonstrated similar levels of reinnervation, whereas retrograde labelling studies confirmed that the peroneal nerve-innervated muscles were innervated by neurons from the tibial nerve pool in the nerve transfer group. Our results demonstrate a task-dependent recovery process, where skilled locomotor recovery is similar between nerve transfer and direct repair animals, whereas flat surface locomotion is significantly better in direct repair animals. PMID:20377620

  11. Histopathologic findings in autogenous saphenous vein graft wrapping for recurrent tarsal tunnel syndrome: a case report.

    PubMed

    Campbell, J T; Schon, L C; Burkhardt, L D

    1998-11-01

    Autogenous saphenous vein graft wrapping of the tibial nerve has been described as an effective treatment option for failed tarsal tunnel decompression. Various theories have been proposed to explain how this method works, with little histologic evidence to date. A pathologic investigation of a sectioned nerve that had been previously wrapped provides some insight into these proposals. PMID:9840207

  12. Healing Rates in a Multicenter Assessment of a Sterile, Room Temperature, Acellular Dermal Matrix Versus Conventional Care Wound Management and an Active Comparator in the Treatment of Full-Thickness Diabetic Foot Ulcers

    PubMed Central

    Cazzell, Shawn; Pham, Hau; Vayser, Dean; Reyzelman, Alexander

    2016-01-01

    Objective: The purpose of this 16-week, multicenter, randomized, controlled trial was to assess the healed ulcer rate of a human acellular dermal matrix, DermACELL, compared with conventional care and a second acellular dermal matrix, Graftjacket, in the treatment of full-thickness diabetic foot ulcers. Methods: One hundred sixty-eight patients were randomized into DermACELL, conventional care, and Graftjacket treatment arms in a 2:2:1 ratio. Patients in the acellular dermal matrix groups received either 1 or 2 applications of the graft at the discretion of the investigator. Weekly follow-up visits were conducted until the ulcer healed or the endpoint was reached. Results: At 16 weeks, the DermACELL arm had a significantly higher proportion of completely healed ulcers than the conventional care arm (67.9% vs 48.1%; P = .0385) and a nonsignificantly higher proportion than the Graftjacket arm (67.9% vs 47.8%; P = .1149). The DermACELL arm also exhibited a greater average percent reduction in wound area than the conventional care arm (91.4% vs 80.3%; P = .0791) and the Graftjacket arm (91.4% vs 73.5%; P = .0762). The proportion of severe adverse events and the proportion of overall early withdrawals were similar among the 3 groups based on relative population size (P ≥ .05). Conclusions: The results presented here indicate that DermACELL is an appropriate clinical option in the treatment of diabetic foot ulcers, with significant increases in healing rates and rate of percentage wound closure as compared with conventional care options. PMID:26933467

  13. Root coverage using a coronally advanced flap with or without acellular dermal matrix: a meta-analysis

    PubMed Central

    2016-01-01

    Purpose Gingival recession is a major esthetic concern and may lead to root sensitivity during periodontal treatment. Coronally advanced flaps (CAFs) with and without acellular dermal matrix (ADM) are widely used in root coverage procedures. The aim of this study was to analyze the efficacy of CAF in combination with ADM in the treatment of gingival recession. Methods PubMed, The Cochrane Library, and Embase were used to identify relevant articles. The articles were screened, data were extracted, and the quality of the studies was assessed by three reviewers with expertise in clinical practice, trials, statistics, and biomedical editing. The clinical endpoints of interest included changes in recession, probing depth (PD), clinical attachment level (CAL), and keratinized tissue (KT). Results Ten randomized controlled trials were identified, including six studies that compared CAFs with ADM and CAFs using connective tissue grafting (CTG) and four studies that compared CAFs with or without ADM. No statistically significant differences were found between the use of ADM and CTG, whereas statistically significant differences were found between groups in which ADM and CAF were combined and groups that underwent CAF alone with regard to recession coverage, CAL, and KT. The combination of CAF with an ADM allograft achieved more favorable recession coverage and recovery of CAL and KT than CAF alone. Conclusions The results from the ADM and CTG groups suggest that both procedures may be equally effective in clinical practice. Given the limitations of this study, further investigation is needed to clarify the effectiveness of ADM and CAF in clinical practice. PMID:26937291

  14. Ectopic bone formation in rapidly fabricated acellular injectable dense collagen-Bioglass hybrid scaffolds via gel aspiration-ejection.

    PubMed

    Miri, Amir K; Muja, Naser; Kamranpour, Neysan O; Lepry, William C; Boccaccini, Aldo R; Clarke, Susan A; Nazhat, Showan N

    2016-04-01

    Gel aspiration-ejection (GAE) has recently been introduced as an effective technique for the rapid production of injectable dense collagen (IDC) gel scaffolds with tunable collagen fibrillar densities (CFDs) and microstructures. Herein, a GAE system was applied for the advanced production and delivery of IDC and IDC-Bioglass(®) (IDC-BG) hybrid gel scaffolds for potential bone tissue engineering applications. The efficacy of GAE in generating mineralizable IDC-BG gels (from an initial 75-25 collagen-BG ratio) produced through needle gauge numbers 8G (3.4 mm diameter and 6 wt% CFD) and 14G (1.6 mm diameter and 14 wt% CFD) was investigated. Second harmonic generation (SHG) imaging of as-made gels revealed an increase in collagen fibril alignment with needle gauge number. In vitro mineralization of IDC-BG gels was confirmed where carbonated hydroxyapatite was detected as early as day 1 in simulated body fluid, which progressively increased up to day 14. In vivo mineralization of, and host response to, acellular IDC and IDC-BG gel scaffolds were further investigated following subcutaneous injection in adult rats. Mineralization, neovascularization and cell infiltration into the scaffolds was enhanced by the addition of BG and at day 21 post injection, there was evidence of remodelling of granulation tissue into woven bone-like tissue in IDC-BG. SHG imaging of explanted scaffolds indicated collagen fibril remodelling through cell infiltration and mineralization over time. In sum, the results suggest that IDC-BG hybrid gels have osteoinductive properties and potentially offer a novel therapeutic approach for procedures requiring the injectable delivery of a malleable and dynamic bone graft that mineralizes under physiological conditions. PMID:26871889

  15. Mechanical and biocompatible characterizations of a readily available multilayer vascular graft

    PubMed Central

    Madhavan, Krishna; Elliott, Winston H; Bonani, Walter; Monnet, Eric; Tan, Wei

    2013-01-01

    There is always a considerable clinical need for vascular grafts. Considering the availability, physical and mechanical properties, and regenerative potential, we have developed and characterized readily available, strong, and compliant multilayer grafts that support cell culture and ingrowth. The grafts were made from heterogeneous materials and structures, including a thin, dense, nanofibrous core composed of poly-ε-caprolactone (PCL), and a thick, porous, hydrogel sleeve composed of genipin-crosslinked collagen–chitosan (GCC). Because the difference in physicochemical properties between PCL and GCC caused layer separation, the layer adhesion was identified as a determinant to graft property and integrity under physiological conditions. Thus, strategies to modify the layer interface, including increasing porosity of the PCL surface, decreasing hydrophobicity, and increasing interlayer crosslinking, were developed. Results from microscopic images showed that increasing PCL porosity was characterized by improved layer adhesion. The resultant graft was characterized by high compliance (4.5%), and desired permeability (528 mL/cm2/min), burst strength (695 mmHg), and suture strength (2.38 N) for readily grafting. Results also showed that PCL mainly contributed to the graft mechanical properties, whereas GCC reduced the water permeability. In addition to their complementary contributions to physical and mechanical properties, the distinct graft layers also provided layer-specific structures for seeding and culture of vascular endothelial and smooth muscle cells in vitro. Acellular graft constructs were readily used to replace abdominal aorta of rabbits, resulting in rapid cell ingrowth and flow reperfusion. The multilayer constructs capable of sustaining physiological conditions and promoting cellular activities could serve as a platform for future development of regenerative vascular grafts. PMID:23165922

  16. Cross-face nerve transfer for established trigeminal branch II palsy.

    PubMed

    Koshima, Isao; Narushima, Mitsunaga; Mihara, Makoto; Uchida, Gentaro; Nakagawa, Masahiro

    2009-12-01

    Reconstruction for trigeminal nerve II palsy is challenging. Cross-face nerve transfer from the contralateral trigeminal nerve facilitates this reconstruction. However, the microanatomy and techniques required for nerve sutures cause problems for many surgeons. Following the recent development of supramicrosurgical techniques appropriate for the microanatomy of peripheral nerves, a new method of intraoral "cross-face nerve transfer" was successfully used for repairing trigeminal nerve II palsy. Two cases of trigeminal nerve II palsy were repaired with contralateral trigeminal nerve transfer without any nerve graft. Affected upper labial sensory recovery was 1.65 to 2.44 (Semmes-Weinstein values) and 15 to 30 mm (moving 2-point discriminations) at 1 to 1 1/2 years after surgery. The advantages of this method are excellent nerve regeneration and the lack of donor site morbidity. It is a brief and simple operation in comparison to free nerve grafts. The disadvantage is a need for a supramicrosurgical technique, using a needle less than 80 microm wide. PMID:19934846

  17. Lateralization Technique and Inferior Alveolar Nerve Transposition

    PubMed Central

    Sanches, Marco Antonio; Ramalho, Gabriel Cardoso; Manzi, Marcello Roberto

    2016-01-01

    Bone resorption of the posterior mandible can result in diminished bone edge and, therefore, the installation of implants in these regions becomes a challenge, especially in the presence of the mandibular canal and its contents, the inferior alveolar nerve. Several treatment alternatives are suggested: the use of short implants, guided bone regeneration, appositional bone grafting, distraction osteogenesis, inclined implants tangential to the mandibular canal, and the lateralization of the inferior alveolar nerve. The aim was to elucidate the success rate of implants in the lateralization technique and in inferior alveolar nerve transposition and to determine the most effective sensory test. We conclude that the success rate is linked to the possibility of installing implants with long bicortical anchor which favors primary stability and biomechanics. PMID:27433360

  18. Histologic evaluation of a biopsy specimen obtained 3 months after rotator cuff augmentation with GraftJacket Matrix.

    PubMed

    Snyder, Stephen J; Arnoczky, Steven P; Bond, James L; Dopirak, Ryan

    2009-03-01

    Understanding the cellular response to a biologic graft used in rotator cuff applications is important because foreign-body reactions and inflammation complications have historically been seen with xenograft-derived grafts. The purpose of this study was to histologically evaluate a biopsy specimen taken from a rotator cuff of a 62-year-old man 3 months after augmentation with an acellular human dermal graft, GraftJacket Matrix-MaxForce Extreme (Wright Medical Technology, Arlington, TN). The graft material was intact and filled with numerous elastic fibers and blood vessels. Extensive host cellular infiltration was evident along the margins of the graft, whereas the more central regions were more sparsely populated. Calcification and infection were not evident. There was little to no inflammatory response. The orientation of the collagen fibers indicated early organization of new tissue. The incorporation of the GraftJacket Matrix-MaxForce Extreme evidenced by cellular infiltration, alignment of collagen fibers, and blood vessel ingrowth shows that this graft exhibits key biologic factors of the remodeling process when used as an augmentation device in rotator cuff repair. PMID:19245998

  19. Development of a Regenerative Peripheral Nerve Interface for Control of a Neuroprosthetic Limb

    PubMed Central

    Frost, Christopher M.; Martin, David C.; Larkin, Lisa M.

    2016-01-01

    Background. The purpose of this experiment was to develop a peripheral nerve interface using cultured myoblasts within a scaffold to provide a biologically stable interface while providing signal amplification for neuroprosthetic control and preventing neuroma formation. Methods. A Regenerative Peripheral Nerve Interface (RPNI) composed of a scaffold and cultured myoblasts was implanted on the end of a divided peroneal nerve in rats (n = 25). The scaffold material consisted of either silicone mesh, acellular muscle, or acellular muscle with chemically polymerized poly(3,4-ethylenedioxythiophene) conductive polymer. Average implantation time was 93 days. Electrophysiological tests were performed at endpoint to determine RPNI viability and ability to transduce neural signals. Tissue samples were examined using both light microscopy and immunohistochemistry. Results. All implanted RPNIs, regardless of scaffold type, remained viable and displayed robust vascularity. Electromyographic activity and stimulated compound muscle action potentials were successfully recorded from all RPNIs. Physiologic efferent motor action potentials were detected from RPNIs in response to sensory foot stimulation. Histology and transmission electron microscopy revealed mature muscle fibers, axonal regeneration without neuroma formation, neovascularization, and synaptogenesis. Desmin staining confirmed the preservation and maturation of myoblasts within the RPNIs. Conclusions. RPNI demonstrates significant myoblast maturation, innervation, and vascularization without neuroma formation. PMID:27294122

  20. Surgical treatment of posterior interosseous nerve paralysis in a tennis player☆

    PubMed Central

    Fujioka, Hiroyuki; Tsunemi, Kenjiro; Tsukamoto, Yoshitane; Oi, Takanori; Takagi, Yohei; Tanaka, Juichi; Yoshiya, Shinichi

    2014-01-01

    We report a rare case of posterior interosseous nerve (PIN) paralysis in a tennis player. The PIN, a 2 cm section from a bifurcation point of the radial nerve, presented increased stiffness in the surgical findings and treated with free sural nerve grafting after excision of the degenerative portion of the PIN. We speculate that PIN paralysis associated with hourglass-like constriction can be caused and exacerbated by repetitive forearm pronation and supination in playing tennis. PMID:25104896

  1. Bone grafts in dentistry

    PubMed Central

    Kumar, Prasanna; Vinitha, Belliappa; Fathima, Ghousia

    2013-01-01

    Bone grafts are used as a filler and scaffold to facilitate bone formation and promote wound healing. These grafts are bioresorbable and have no antigen-antibody reaction. These bone grafts act as a mineral reservoir which induces new bone formation. PMID:23946565

  2. Partial glossectomy and floor of mouth (FOM) defect repair with biological dural graft: A case report

    PubMed Central

    Al-Ghamdi, Khalid B.; Bakhsh, Zainab A.

    2015-01-01

    Introduction Oral carcinoma can cause significant defects that would necessitate a challenging reconstructive surgery. These techniques include biological or synthetic dressings, grafts, regional flaps, and free-vascularized flaps. Among these, the dural graft has demonstrated promising results in repairing the skull-base defects. Our aim is to report a new, innovative technique for partial glossectomy and floor of mouth defect repair using a biological dural graft dressing when primary repair was not feasible and the patient did not consent to dermal graft or flap interventions. Presentation of case This article reports the outcomes from a novel intervention of partial glossectomy repair using a biological dural dressing derived from bovine type-I collagen in a 57-year-old female patient with recurrent T1N1M0 squamous cell carcinoma of the left-sided tongue during the 12 month period of follow-up. Discussion The best option for large tongue defects is a free flap, while for a moderate defect is a regional oral flap. The biological graft, as an acellular dermal graft has been well known to facilitate secondary healing in the tongue as an alternative to the split-thickness skin graft. In the current study, the dural dressing in tongue reconstruction was likewise shown to be an effective biological dressing; hence, the collagen membrane is biologically acceptable to the oral mucosa and an excellent wound graft material. However, it is absolutely contraindicated in bovine hypersensitive patients. Conclusion The biological dural graft dressing appears to be an effective method for tongue reconstruction, as it promotes adequate wound healing and it preserves function. PMID:25942748

  3. Neural tissue engineering options for peripheral nerve regeneration.

    PubMed

    Gu, Xiaosong; Ding, Fei; Williams, David F

    2014-08-01

    Tissue engineered nerve grafts (TENGs) have emerged as a potential alternative to autologous nerve grafts, the gold standard for peripheral nerve repair. Typically, TENGs are composed of a biomaterial-based template that incorporates biochemical cues. A number of TENGs have been used experimentally to bridge long peripheral nerve gaps in various animal models, where the desired outcome is nerve tissue regeneration and functional recovery. So far, the translation of TENGs to the clinic for use in humans has met with a certain degree of success. In order to optimize the TENG design and further approach the matching of TENGs with autologous nerve grafts, many new cues, beyond the traditional ones, will have to be integrated into TENGs. Furthermore, there is a strong requirement for monitoring the real-time dynamic information related to the construction of TENGs. The aim of this opinion paper is to specifically and critically describe the latest advances in the field of neural tissue engineering for peripheral nerve regeneration. Here we delineate new attempts in the design of template (or scaffold) materials, especially in the context of biocompatibility, the choice and handling of support cells, and growth factor release systems. We further discuss the significance of RNAi for peripheral nerve regeneration, anticipate the potential application of RNAi reagents for TENGs, and speculate on the possible contributions of additional elements, including angiogenesis, electrical stimulation, molecular inflammatory mediators, bioactive peptides, antioxidant reagents, and cultured biological constructs, to TENGs. Finally, we consider that a diverse array of physicochemical and biological cues must be orchestrated within a TENG to create a self-consistent coordinated system with a close proximity to the regenerative microenvironment of the peripheral nervous system. PMID:24818883

  4. Prosthetic Breast Reconstruction With Acellular Dermal Matrices: Achieving Predictability and Reproducibility.

    PubMed

    Nahabedian, Maurice Y

    2016-05-01

    The use of acellular dermal matrices in the setting of prosthetic breast reconstruction has captured the attention of many plastic surgeons. The regenerative capacity of these materials has provided additional tissue support to the mastectomy skin flaps with the ultimate result of improving surgical and aesthetic outcomes. Despite the benefits, there remains a significant diversity with regard to outcomes with some surgeons reporting increased morbidity. The reasons for this are varied but ultimately related to differences in patient selection and surgical techniques. The purpose of this article is to provide strategies for using acellular dermal matrix to achieve success in a manner that is usually associated with outcomes that are predictable and reproducible. PMID:27579223

  5. Pioneering technique using Acellular Dermal Matrix in the rescue of a radiation ulcer

    PubMed Central

    NASEEM, S.; PATEL, A.D.; DEVALIA, H.

    2016-01-01

    Background Radiotherapy as an adjuvant to mastectomy is integral to the treatment of breast cancer, but can result in skin ulceration. Skin ulceration following radiotherapy is traditionally managed by removing the implant and allowing the skin to heal by secondary intention. Case report A 42-year-old woman underwent radiotherapy following a breast reconstruction. She developed a 2 x 3cm radiation ulcer. The ulcer was managed by removing the implant and performing capsulectomy. A Beckers 50 expander was placed and reinforced with acellular dermal matrix inferolaterally. At follow-up the patient had a good cosmetic outcome. Conclusion Post-radiation skin ulcers present a challenge to treat with no current standardised management. The use of acellular dermal matrix may present a new technique to promote healing in these testing cases. PMID:27142826

  6. Prosthetic Breast Reconstruction With Acellular Dermal Matrices: Achieving Predictability and Reproducibility

    PubMed Central

    2016-01-01

    Summary: The use of acellular dermal matrices in the setting of prosthetic breast reconstruction has captured the attention of many plastic surgeons. The regenerative capacity of these materials has provided additional tissue support to the mastectomy skin flaps with the ultimate result of improving surgical and aesthetic outcomes. Despite the benefits, there remains a significant diversity with regard to outcomes with some surgeons reporting increased morbidity. The reasons for this are varied but ultimately related to differences in patient selection and surgical techniques. The purpose of this article is to provide strategies for using acellular dermal matrix to achieve success in a manner that is usually associated with outcomes that are predictable and reproducible. PMID:27579223

  7. Peripheral nerve regeneration with conduits: use of vein tubes

    PubMed Central

    Sabongi, Rodrigo Guerra; Fernandes, Marcela; dos Santos, João Baptista Gomes

    2015-01-01

    Treatment of peripheral nerve injuries remains a challenge to modern medicine due to the complexity of the neurobiological nerve regenerating process. There is a greater challenge when the transected nerve ends are not amenable to primary end-to-end tensionless neurorraphy. When facing a segmental nerve defect, great effort has been made to develop an alternative to the autologous nerve graft in order to circumvent morbidity at donor site, such as neuroma formation, scarring and permanent loss of function. Tubolization techniques have been developed to bridge nerve gaps and have been extensively studied in numerous experimental and clinical trials. The use of a conduit intends to act as a vehicle for moderation and modulation of the cellular and molecular ambience for nerve regeneration. Among several conduits, vein tubes were validated for clinical application with improving outcomes over the years. This article aims to address the investigation and treatment of segmental nerve injury and draw the current panorama on the use of vein tubes as an autogenous nerve conduit. PMID:26170802

  8. Hertwig's epithelial root sheath cell behavior during initial acellular cementogenesis in rat molars.

    PubMed

    Yamamoto, Tsuneyuki; Yamamoto, Tomomaya; Yamada, Tamaki; Hasegawa, Tomoka; Hongo, Hiromi; Oda, Kimimitsu; Amizuka, Norio

    2014-11-01

    This study was designed to examine developing acellular cementum in rat molars by immunohistochemistry, to elucidate (1) how Hertwig's epithelial root sheath disintegrates and (2) whether epithelial sheath cells transform into cementoblasts through epithelial-mesenchymal transition (EMT). Initial acellular cementogenesis was divided into three developmental stages, which can be seen in three different portions of the root: portion 1, where the epithelial sheath is intact; portion 2, where the epithelial sheath becomes fragmented; and portion 3, where acellular cementogenesis begins. Antibodies against three kinds of matrix proteinases, which degrade epithelial sheath-maintaining factors, including basement membrane and desmosomes, were used to investigate proteolytic activity of the epithelial sheath. Tissue non-specific alkaline phosphatase (TNALP) and keratin were used to investigate EMT. Epithelial sheath cells showed immunoreactivity for all three enzymes at fragmentation, which suggests that epithelial sheath disintegration is enzymatically mediated. Dental follicle cells and cementoblasts showed intense immunoreactivity for TNALP, and from portion 1 through to 3, the reaction extended from the alveolar bone-related zone to the root-related zone. Cells possessing keratin/TNALP double immunoreactivity were virtually absent. Keratin-positive epithelial sheath cells showed negligible immunoreactivity for TNALP, and epithelial cells did not appear to migrate to the dental follicle. Together, these findings suggest that a transition phenotype between epithelial cells and cementoblasts does not exist in the developing dental follicle and hence that epithelial sheath cells do not undergo EMT during initial acellular cementogenesis. In brief, this study supports the notion that cementoblasts derive from the dental follicle. PMID:24859538

  9. Immunolocation of proteoglycans and bone-related noncollagenous glycoproteins in developing acellular cementum of rat molars.

    PubMed

    Yamamoto, T; Domon, T; Takahashi, S; Arambawatta, A K S; Wakita, M

    2004-09-01

    To elucidate the roles of proteoglycans of (PGs), bone sialoprotein (BSP), and osteopontin (OPN) in cementogenesis, their distribution was investigated in developing and established acellular cementum of rat molars by an immunoperoxidase method. To characterize PGs, antibodies against five species of glycosaminoglycans (GAGS), chondroitin-4-sulfate (C4S), chondroitin-6-sulfate (C6S), unsulfated chondroitin (C0S), dermatan sulfate (DS), and keratan sulfate (KS) were used. Routine histological staining was also applied. With onset of dentin mineralization, the initial cementum appeared on the dentin surface as a hematoxylin-stained fibril-poor layer. Subsequently, primitive principal fibers attached to the initial cementum. As the acellular cementum containing extrinsic fibers covered the initial cementum, the intal cementum formed the cemento-dentinal junction. Following immunohistochemistry at the earliest time of cementogenesis, the initial cementum was intensely immunoreactive for C4S, C6S, C0S, BSP, and OPN. After the initial cementum was embedded, neither the cemento-dentinal junction nor the cementum was immunoreactive for any GAG species. However, the cementum was immunoreactive for any GAG species. However, the cementum and cemento-dentinal were consistently immunoreactive for BSP. Although the cemento-dentinal junction was consistently immunoreactive for OPN, the remaining cementum showed no significant immunoreactivity. Thus, initial acellular cementogenesis requires a dense accumulation of PGs, BSP, and OPN, which may be associated with the mineralization process independently of collagen fibrils and initial principal fiber attachment. PMID:15278434

  10. Preparation and characterization of an acellular bovine pericardium intended for manufacture of valve bioprostheses.

    PubMed

    Goissis, Gilberto; Giglioti, Aparecida de Fátima; Braile, Domingo Marcolino

    2011-05-01

    Major problems with biological heart valves post-implantation are associated with progressive structural deterioration and calcification attributed to glutaraldehyde processing, dead cells, and cell fragments present in the native tissue. In spite of these problems, glutaraldehyde still is the reagent of choice. The results with acellular matrix xenograft usually prepared by detergent treatment in association with enzymes are rather conflicting because while preserving mechanical properties, tissue morphology and collagen structure are process dependent. This work describes a chemical approach for the preparation of an acellular bovine pericardium matrix intended for the manufacture of heart valve bioprostheses. Cell removal was performed by an alkaline extraction in the presence of calcium salts for periods ranging from 6 to 48 h. The results showed that cell removal was achieved after 12 h, with swelling and negative charge increasing with processing time. Nevertheless, collagen fibril structure, ability to form fibrils, and stability to collagenase were progressive after 24-h processing. There was no denaturation of the collagen matrix. A process is described for the preparation of acellular bovine pericardium matrices with preserved fibril structure and morphology for the manufacture of cardiac valve bioprostheses and may be used in other applications for tissue reconstruction. PMID:21595716

  11. Mannose-6-phosphate facilitates early peripheral nerve regeneration in thy-1-YFP-H mice.

    PubMed

    Harding, A J; Christmas, C R; Ferguson, M W J; Loescher, A R; Robinson, P P; Boissonade, F M

    2014-10-24

    The formation of scar tissue following nerve injury has been shown to adversely affect nerve regeneration and evidence suggests that mannose-6-phosphate (M6P), a potential scar reducing agent that affects transforming growth factor (TGF)-β activation, may enhance nerve regeneration. In this study we utilized thy-1-YFP-H mice - a transgenic strain expressing yellow fluorescent protein (YFP) within a subset of axons - to enable visual analysis of axons regenerating through a nerve graft. Using this strain of mouse we have developed analysis techniques to visualize and quantify regeneration of individual axons across the injury site following the application of either M6P or vehicle to the site of nerve injury. No significant differences were found in the proportion of axons regenerating through the graft between M6P- and vehicle-treated grafts at any point along the graft length. Maximal sprouting occurred at 1.0mm from the proximal graft ending in both groups. The maximum change in sprouting levels for both treatment groups occurred between the graft start and 0.5-mm interval for both treatment groups. The difference between repair groups was significant at this point with a greater increase seen in the vehicle group than the M6P group. The average length of axons regenerating across the initial graft entry was significantly shorter in M6P- than in vehicle-treated grafts, indicating that they encountered less impedance. Application of M6P appears to reduce the disruption of regenerating axons and may therefore facilitate quicker recovery; this is likely to result from altered scar tissue formation in M6P grafts in the early stages of recovery. This study also establishes the usefulness of our methods of analysis using the thy-1-YFP-H mouse strain to visualize and quantify regeneration at the level of the individual axon. PMID:25173153

  12. Electrospun biodegradable elastic polyurethane scaffolds with dipyridamole release for small diameter vascular grafts.

    PubMed

    Punnakitikashem, Primana; Truong, Danh; Menon, Jyothi U; Nguyen, Kytai T; Hong, Yi

    2014-11-01

    Acellular biodegradable small diameter vascular grafts (SDVGs) require antithrombosis, intimal hyperplasia inhibition and rapid endothelialization to improve the graft patency. However, current antithrombosis and antiproliferation approaches often conflict with endothelial cell layer formation on SDVGs. To address this limitation, biodegradable elastic polyurethane urea (BPU) and the drug dipyridamole (DPA) were mixed and then electrospun into a biodegradable fibrous scaffold. The BPU would provide the appropriate mechanical support, while the DPA in the scaffold would offer biofunctions as required above. We found that the resulting scaffolds had tensile strengths and strains comparable with human coronary artery. The DPA in the scaffolds was continuously released up to 91 days in phosphate buffer solution at 37 °C, with a low burst release within the first 3 days. Compared to BPU alone, improved non-thrombogenicity of the DPA-loaded BPU scaffolds was evidenced with extended human blood clotting time, lower TAT complex concentration, lower hemolysis and reduced human platelet deposition. The scaffolds with a higher DPA content (5 and 10%) inhibited proliferation of human aortic smooth muscle cell significantly. Furthermore, the DPA-loaded scaffolds had no adverse effect on human aortic endothelial cell growth, yet it improved their proliferation. The attractive mechanical properties and biofunctions of the DPA-loaded BPU scaffold indicate its potential as an acellular biodegradable SDVG for vascular replacement. PMID:25110284

  13. Electrospun biodegradable elastic polyurethane scaffolds with dipyridamole release for small diameter vascular grafts

    PubMed Central

    Punnakitikashem, Primana; Truong, Danh; Menon, Jyothi U.; Nguyen, Kytai T.; Hong, Yi

    2014-01-01

    Acellular biodegradable small diameter vascular grafts (SDVGs) require antithrombosis, intimal hyperplasia inhibition and rapid endothelialization to improve the graft patency. However, current antithrombosis and antiproliferation approaches often conflict with endothelial cell layer formation on SDVGs. To address this limitation, biodegradable elastic polyurethane urea (BPU) and the drug dipyridamole (DPA) were mixed and then electrospun into a biodegradable fibrous scaffold. The BPU would provide the appropriate mechanical support, while the DPA in the scaffold would offer biofunctions as required above. We found that the resulting scaffolds had tensile strengths and strains comparable with human coronary artery. The DPA in the scaffolds was continuously released up to 91 days in phosphate buffer solution at 37 °C, with a low burst release within the first 3 days. Compared to BPU alone, improved non-thrombogenicity of the DPA-loaded BPU scaffolds was evidenced with extended human blood clotting time, lower TAT complex concentration, lower hemolysis and reduced human platelet deposition. The scaffolds with a higher DPA content (5 and 10%) inhibited proliferation of human aortic smooth muscle cell significantly. Furthermore, the DPA-loaded scaffolds had no adverse effect on human aortic endothelial cell growth, yet it improved their proliferation. The attractive mechanical properties and biofunctions of the DPA-loaded BPU scaffold indicate its potential as an acellular biodegradable SDVG for vascular replacement. PMID:25110284

  14. Engineering a multimodal nerve conduit for repair of injured peripheral nerve.

    PubMed

    Quigley, A F; Bulluss, K J; Kyratzis, I L B; Gilmore, K; Mysore, T; Schirmer, K S U; Kennedy, E L; O'Shea, M; Truong, Y B; Edwards, S L; Peeters, G; Herwig, P; Razal, J M; Campbell, T E; Lowes, K N; Higgins, M J; Moulton, S E; Murphy, M A; Cook, M J; Clark, G M; Wallace, G G; Kapsa, R M I

    2013-02-01

    Injury to nerve tissue in the peripheral nervous system (PNS) results in long-term impairment of limb function, dysaesthesia and pain, often with associated psychological effects. Whilst minor injuries can be left to regenerate without intervention and short gaps up to 2 cm can be sutured, larger or more severe injuries commonly require autogenous nerve grafts harvested from elsewhere in the body (usually sensory nerves). Functional recovery is often suboptimal and associated with loss of sensation from the tissue innervated by the harvested nerve. The challenges that persist with nerve repair have resulted in development of nerve guides or conduits from non-neural biological tissues and various polymers to improve the prognosis for the repair of damaged nerves in the PNS. This study describes the design and fabrication of a multimodal controlled pore size nerve regeneration conduit using polylactic acid (PLA) and (PLA):poly(lactic-co-glycolic) acid (PLGA) fibers within a neurotrophin-enriched alginate hydrogel. The nerve repair conduit design consists of two types of PLGA fibers selected specifically for promotion of axonal outgrowth and Schwann cell growth (75:25 for axons; 85:15 for Schwann cells). These aligned fibers are contained within the lumen of a knitted PLA sheath coated with electrospun PLA nanofibers to control pore size. The PLGA guidance fibers within the nerve repair conduit lumen are supported within an alginate hydrogel impregnated with neurotrophic factors (NT-3 or BDNF with LIF, SMDF and MGF-1) to provide neuroprotection, stimulation of axonal growth and Schwann cell migration. The conduit was used to promote repair of transected sciatic nerve in rats over a period of 4 weeks. Over this period, it was observed that over-grooming and self-mutilation (autotomy) of the limb implanted with the conduit was significantly reduced in rats implanted with the full-configuration conduit compared to rats implanted with conduits containing only an alginate

  15. Engineering a multimodal nerve conduit for repair of injured peripheral nerve

    NASA Astrophysics Data System (ADS)

    Quigley, A. F.; Bulluss, K. J.; Kyratzis, I. L. B.; Gilmore, K.; Mysore, T.; Schirmer, K. S. U.; Kennedy, E. L.; O'Shea, M.; Truong, Y. B.; Edwards, S. L.; Peeters, G.; Herwig, P.; Razal, J. M.; Campbell, T. E.; Lowes, K. N.; Higgins, M. J.; Moulton, S. E.; Murphy, M. A.; Cook, M. J.; Clark, G. M.; Wallace, G. G.; Kapsa, R. M. I.

    2013-02-01

    Injury to nerve tissue in the peripheral nervous system (PNS) results in long-term impairment of limb function, dysaesthesia and pain, often with associated psychological effects. Whilst minor injuries can be left to regenerate without intervention and short gaps up to 2 cm can be sutured, larger or more severe injuries commonly require autogenous nerve grafts harvested from elsewhere in the body (usually sensory nerves). Functional recovery is often suboptimal and associated with loss of sensation from the tissue innervated by the harvested nerve. The challenges that persist with nerve repair have resulted in development of nerve guides or conduits from non-neural biological tissues and various polymers to improve the prognosis for the repair of damaged nerves in the PNS. This study describes the design and fabrication of a multimodal controlled pore size nerve regeneration conduit using polylactic acid (PLA) and (PLA):poly(lactic-co-glycolic) acid (PLGA) fibers within a neurotrophin-enriched alginate hydrogel. The nerve repair conduit design consists of two types of PLGA fibers selected specifically for promotion of axonal outgrowth and Schwann cell growth (75:25 for axons; 85:15 for Schwann cells). These aligned fibers are contained within the lumen of a knitted PLA sheath coated with electrospun PLA nanofibers to control pore size. The PLGA guidance fibers within the nerve repair conduit lumen are supported within an alginate hydrogel impregnated with neurotrophic factors (NT-3 or BDNF with LIF, SMDF and MGF-1) to provide neuroprotection, stimulation of axonal growth and Schwann cell migration. The conduit was used to promote repair of transected sciatic nerve in rats over a period of 4 weeks. Over this period, it was observed that over-grooming and self-mutilation (autotomy) of the limb implanted with the conduit was significantly reduced in rats implanted with the full-configuration conduit compared to rats implanted with conduits containing only an alginate

  16. Ulnar nerve damage (image)

    MedlinePlus

    ... arm. The nerve is commonly injured at the elbow because of elbow fracture or dislocation. The ulnar nerve is near ... surface of the body where it crosses the elbow, so prolonged pressure on the elbow or entrapment ...

  17. Nerve Injuries in Athletes.

    ERIC Educational Resources Information Center

    Collins, Kathryn; And Others

    1988-01-01

    Over a two-year period this study evaluated the condition of 65 athletes with nerve injuries. These injuries represent the spectrum of nerve injuries likely to be encountered in sports medicine clinics. (Author/MT)

  18. Radial nerve dysfunction (image)

    MedlinePlus

    The radial nerve travels down the arm and supplies movement to the triceps muscle at the back of the upper arm. ... the wrist and hand. The usual causes of nerve dysfunction are direct trauma, prolonged pressure on the ...

  19. Tibial nerve dysfunction

    MedlinePlus

    ... a loss of movement or sensation in the foot from damage to the tibial nerve. ... Tibial nerve dysfunction is an unusual form of peripheral ... the calf and foot muscles. A problem in function with a single ...

  20. Nerve conduction velocity

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003927.htm Nerve conduction velocity To use the sharing features on this page, please enable JavaScript. Nerve conduction velocity (NCV) is a test to see how ...

  1. Assessing nerves in leprosy.

    PubMed

    Garbino, José Antonio; Heise, Carlos Otto; Marques, Wilson

    2016-01-01

    Leprosy neuropathy is dependent on the patient's immune response and expresses itself as a focal or multifocal neuropathy with asymmetric involvement. Leprosy neuropathy evolves chronically but recurrently develops periods of exacerbation during type 1 or type 2 reactions, leading to acute neuropathy. Nerve enlargement leading to entrapment syndromes is also a common manifestation. Pain may be either of inflammatory or neuropathic origin. A thorough and detailed evaluation is mandatory for adequate patient follow-up, including nerve palpation, pain assessment, graded sensory mapping, muscle power testing, and autonomic evaluation. Nerve conduction studies are a sensitive tool for nerve dysfunction, including new lesions during reaction periods or development of entrapment syndromes. Nerve ultrasonography is also a very promising method for nerve evaluation in leprosy. The authors propose a composite nerve clinical score for nerve function assessment that can be useful for longitudinal evaluation. PMID:26773623

  2. Electromechanical Nerve Stimulator

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

    1993-01-01

    Nerve stimulator applies and/or measures precisely controlled force and/or displacement to nerve so response of nerve measured. Consists of three major components connected in tandem: miniature probe with spherical tip; transducer; and actuator. Probe applies force to nerve, transducer measures force and sends feedback signal to control circuitry, and actuator positions force transducer and probe. Separate box houses control circuits and panel. Operator uses panel to select operating mode and parameters. Stimulator used in research to characterize behavior of nerve under various conditions of temperature, anesthesia, ventilation, and prior damage to nerve. Also used clinically to assess damage to nerve from disease or accident and to monitor response of nerve during surgery.

  3. Radial nerve dysfunction

    MedlinePlus

    ... nerve leads to problems with movement in the arm and wrist and with sensation in the back of the arm or hand. ... to the radial nerve, which travels down the arm and controls movement of the triceps muscle at ...

  4. Degenerative Nerve Diseases

    MedlinePlus

    Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many ... viruses. Sometimes the cause is not known. Degenerative nerve diseases include Alzheimer's disease Amyotrophic lateral sclerosis Friedreich's ...

  5. Advances of Peripheral Nerve Repair Techniques to Improve Hand Function: A Systematic Review of Literature

    PubMed Central

    P, Mafi; S, Hindocha; M, Dhital; M, Saleh

    2012-01-01

    Concepts of neuronal damage and repair date back to ancient times. The research in this topic has been growing ever since and numerous nerve repair techniques have evolved throughout the years. Due to our greater understanding of nerve injuries and repair we now distinguish between central and peripheral nervous system. In this review, we have chosen to concentrate on peripheral nerve injuries and in particular those involving the hand. There are no reviews bringing together and summarizing the latest research evidence concerning the most up-to-date techniques used to improve hand function. Therefore, by identifying and evaluating all the published literature in this field, we have summarized all the available information about the advances in peripheral nerve techniques used to improve hand function. The most important ones are the use of resorbable poly[(R)-3-hydroxybutyrate] (PHB), epineural end-to-end suturing, graft repair, nerve transfer, side to side neurorrhaphy and end to side neurorrhaphy between median, radial and ulnar nerves, nerve transplant, nerve repair, external neurolysis and epineural sutures, adjacent neurotization without nerve suturing, Agee endoscopic operation, tourniquet induced anesthesia, toe transfer and meticulous intrinsic repair, free auto nerve grafting, use of distal based neurocutaneous flaps and tubulization. At the same time we found that the patient’s age, tension of repair, time of repair, level of injury and scar formation following surgery affect the prognosis. Despite the thorough findings of this systematic review we suggest that further research in this field is needed. PMID:22431951

  6. Reinnervation of hair follicle end organs and Meissner Corpuscles in skin grafts of Macaques.

    PubMed

    Uno, H; Montagna, W

    1982-03-01

    Plugs of occipital hairy scalp and pieces of digital pads were transplanted to the frontal scalp of stump-tailed macaques (Macaca arctoides). Both types of grafts grew well and retained their original appearance for several years. We traced the regrowth and reinnervation of hair follicles and Meissner corpuscles in sequential biopsy specimens of these grafts. Two weeks after transplantation, hair follicles in the grafts appeared to have lost all integrity but began to regrow after 4 weeks. The nerve and organs of hair follicles began to reappear at 8 weeks. Thereafter, grafts with large terminal hairs remained viable in the host bald frontal scalp for as long as 8 yr. In the digital skin grafts, the cytoskeleton of the Meissner corpuscles could be distinguished after 4 weeks; after 8 weeks nerves from the host tissue could be traced to the end organs. Perivascular nerve plexuses and nerves to the piloerector muscles were clearly seen in both types of graft after 8 weeks. PMID:7035577

  7. Outer electrospun polycaprolactone shell induces massive foreign body reaction and impairs axonal regeneration through 3D multichannel chitosan nerve guides.

    PubMed

    Duda, Sven; Dreyer, Lutz; Behrens, Peter; Wienecke, Soenke; Chakradeo, Tanmay; Glasmacher, Birgit; Haastert-Talini, Kirsten

    2014-01-01

    We report on the performance of composite nerve grafts with an inner 3D multichannel porous chitosan core and an outer electrospun polycaprolactone shell. The inner chitosan core provided multiple guidance channels for regrowing axons. To analyze the in vivo properties of the bare chitosan cores, we separately implanted them into an epineural sheath. The effects of both graft types on structural and functional regeneration across a 10 mm rat sciatic nerve gap were compared to autologous nerve transplantation (ANT). The mechanical biomaterial properties and the immunological impact of the grafts were assessed with histological techniques before and after transplantation in vivo. Furthermore during a 13-week examination period functional tests and electrophysiological recordings were performed and supplemented by nerve morphometry. The sheathing of the chitosan core with a polycaprolactone shell induced massive foreign body reaction and impairment of nerve regeneration. Although the isolated novel chitosan core did allow regeneration of axons in a similar size distribution as the ANT, the ANT was superior in terms of functional regeneration. We conclude that an outer polycaprolactone shell should not be used for the purpose of bioartificial nerve grafting, while 3D multichannel porous chitosan cores could be candidate scaffolds for structured nerve grafts. PMID:24818158

  8. Outer Electrospun Polycaprolactone Shell Induces Massive Foreign Body Reaction and Impairs Axonal Regeneration through 3D Multichannel Chitosan Nerve Guides

    PubMed Central

    Behrens, Peter; Wienecke, Soenke; Chakradeo, Tanmay; Glasmacher, Birgit

    2014-01-01

    We report on the performance of composite nerve grafts with an inner 3D multichannel porous chitosan core and an outer electrospun polycaprolactone shell. The inner chitosan core provided multiple guidance channels for regrowing axons. To analyze the in vivo properties of the bare chitosan cores, we separately implanted them into an epineural sheath. The effects of both graft types on structural and functional regeneration across a 10 mm rat sciatic nerve gap were compared to autologous nerve transplantation (ANT). The mechanical biomaterial properties and the immunological impact of the grafts were assessed with histological techniques before and after transplantation in vivo. Furthermore during a 13-week examination period functional tests and electrophysiological recordings were performed and supplemented by nerve morphometry. The sheathing of the chitosan core with a polycaprolactone shell induced massive foreign body reaction and impairment of nerve regeneration. Although the isolated novel chitosan core did allow regeneration of axons in a similar size distribution as the ANT, the ANT was superior in terms of functional regeneration. We conclude that an outer polycaprolactone shell should not be used for the purpose of bioartificial nerve grafting, while 3D multichannel porous chitosan cores could be candidate scaffolds for structured nerve grafts. PMID:24818158

  9. Laryngeal nerve damage

    MedlinePlus

    Laryngeal nerve damage is injury to one or both of the nerves that are attached to the voice box. ... Injury to the laryngeal nerves is uncommon. When it does occur, it can be from: A complication of neck or chest surgery (especially thyroid, lung, ...

  10. Efficacy of nanofibrous conduits in repair of long-segment sciatic nerve defects

    PubMed Central

    Biazar, Esmaeil; Keshel, Saeed Heidari; Pouya, Majid

    2013-01-01

    Our previous studies have histomorphologically confirmed that nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) conduit can be used to repair 30-mm-long sciatic nerve defects. However, the repair effects on rat behaviors remain poorly understood. In this study, we used nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) conduit and autologous sciatic nerve to bridge 30-mm-long rat sciatic nerve gaps. Within 4 months after surgery, rat sciatic nerve functional recovery was evaluated per month by behavioral analyses, including toe out angle, toe spread analysis, walking track analysis, extensor postural thrust, swimming test, open-field analysis and nociceptive function. Results showed that rat sciatic nerve functional recovery was similar after nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) conduit and autologous nerve grafting. These findings suggest that nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) conduit is suitable in use for repair of long-segment sciatic nerve defects. PMID:25206560

  11. Evaluating acellular versus cellular perfusate composition during prolonged ex vivo lung perfusion after initial cold ischaemia for 24 hours.

    PubMed

    Becker, Simon; Steinmeyer, Jasmin; Avsar, Murat; Höffler, Klaus; Salman, Jawad; Haverich, Axel; Warnecke, Gregor; Ochs, Matthias; Schnapper, Anke

    2016-01-01

    Normothermic ex vivo lung perfusion (EVLP) has developed as a powerful technique to evaluate particularly marginal donor lungs prior to transplantation. In this study, acellular and cellular perfusate compositions were compared in an identical experimental setting as no consensus has been reached on a preferred technique yet. Porcine lungs underwent EVLP for 12 h on the basis of an acellular or a cellular perfusate composition after 24 h of cold ischaemia as defined organ stress. During perfusion, haemodynamic and respiratory parameters were monitored. After EVLP, the lung condition was assessed by light and transmission electron microscopy. Aerodynamic parameters did not show significant differences between groups and remained within the in vivo range during EVLP. Mean oxygenation indices were 491 ± 39 in the acellular group and 513 ± 53 in the cellular group. Groups only differed significantly in terms of higher pulmonary artery pressure and vascular resistance in the cellular group. Lung histology and ultrastructure were largely well preserved after prolonged EVLP and showed only minor structural alterations which were similarly present in both groups. Prolonged acellular and cellular EVLP for 12 h are both feasible with lungs prechallenged by ischaemic organ stress. Physiological and ultrastructural analysis showed no superiority of either acellular or cellular perfusate composition. PMID:26264867

  12. Laser Scanning In Vivo Confocal Microscopy of Clear Grafts after Penetrating Keratoplasty

    PubMed Central

    Wang, Dai; Song, Peng; Wang, Shuting; Sun, Dapeng; Wang, Yuexin; Zhang, Yangyang

    2016-01-01

    Purpose. To evaluate the changes of keratocytes and dendritic cells in the central clear graft by laser scanning in vivo confocal microscopy after penetrating keratoplasty (PK). Methods. Thirty adult subjects receiving PK at Shandong Eye Institute and with clear grafts and no sign of immune rejection after surgery were recruited into this study, and 10 healthy adults were controls. The keratocytes and dendritic cells in the central graft were evaluated by laser scanning confocal microscopy, as well as epithelium cells, keratocytes, corneal endothelium cells, and corneal nerves (especially subepithelial plexus nerves). Results. Median density of subepithelial plexus nerves, keratocyte density in each layer of the stroma, and density of corneal endothelium cells were all lower in clear grafts than in controls. The dendritic cells of five (16.7%) patients were active in Bowman's membrane and stromal membrane of the graft after PK. Conclusions. Activated dendritic cells and Langerhans cells could be detected in some of the clear grafts, which indicated that the subclinical stress of immune reaction took part in the chronic injury of the clear graft after PK, even when there was no clinical rejection episode. PMID:27034940

  13. Nerve allograft transplantation for functional restoration of the upper extremity: case series

    PubMed Central

    Elkwood, Andrew I.; Holland, Neil R.; Arbes, Spiros M.; Rose, Michael I.; Kaufman, Matthew R.; Ashinoff, Russell L.; Parikh, Mona A.; Patel, Tushar R.

    2011-01-01

    Background Major trauma to the spinal cord or upper extremity often results in severe sensory and motor disturbances from injuries to the brachial plexus and its insertion into the spinal cord. Functional restoration with nerve grafting neurotization and tendon transfers is the mainstay of treatment. Results may be incomplete due to a limited supply of autologous material for nerve grafts. The factors deemed most integral for success are early surgical intervention, reconstruction of all levels of injury, and maximization of the number of axonal conduits per nerve repair. Objective To report the second series of nerve allograft transplantation using cadaveric nerve graft and our experience with living-related nerve transplants. Participants Eight patients, seven men and one woman, average age 23 years (range 18–34), with multi-level brachial plexus injuries were selected for transplantation using either cadaveric allografts or living-related donors. Methods Grafts were harvested and preserved in the University of Wisconsin Cold Storage Solution at 5°C for up to 7 days. The immunosuppressive protocol was initiated at the time of surgery and was discontinued at approximately 1 year, or when signs of regeneration were evident. Parameters for assessment included mechanism of injury, interval between injury and treatment, level(s) of deficit, post-operative return of function, pain relief, need for revision surgery, complications, and improvement in quality of life. Results Surgery was performed using living-related donor grafts in six patients, and cadaveric grafts in two patients. Immunosuppression was tolerated for the duration of treatment in all but one patient in whom early termination occurred due to non-compliance. There were no cases of graft rejection as of most recent follow-up. Seven patients showed signs of regeneration, demonstrated by return of sensory and motor function and/or a migrating Tinel's sign. One patient was non-compliant with the post

  14. High Median Nerve Injuries.

    PubMed

    Isaacs, Jonathan; Ugwu-Oju, Obinna

    2016-08-01

    The median nerve serves a crucial role in extrinsic and intrinsic motor and sensory function to the radial half of the hand. High median nerve injuries, defined as injuries proximal to the anterior interosseous nerve origin, therefore typically result in significant functional loss prompting aggressive surgical management. Even with appropriate recognition and contemporary nerve reconstruction, however, motor and sensory recovery may be inadequate. With isolated persistent high median nerve palsies, a variety of available tendon transfers can improve key motor functions and salvage acceptable use of the hand. PMID:27387077

  15. Acellular Bi-Layer Silk Fibroin Scaffolds Support Tissue Regeneration in a Rabbit Model of Onlay Urethroplasty

    PubMed Central

    Franck, Debra; Gil, Eun Seok; Algarrahi, Khalid; Adam, Rosalyn M.; Kaplan, David L.; Estrada Jr., Carlos R.; Mauney, Joshua R.

    2014-01-01

    Acellular scaffolds derived from Bombyx mori silk fibroin were investigated for their ability to support functional tissue regeneration in a rabbit model of urethra repair. A bi-layer silk fibroin matrix was fabricated by a solvent-casting/salt leaching process in combination with silk fibroin film casting to generate porous foams buttressed by homogeneous silk fibroin films. Ventral onlay urethroplasty was performed with silk fibroin grafts (Group 1, N = 4) (Width×Length, 1×2 cm2) in adult male rabbits for 3 m of implantation. Parallel control groups consisted of animals receiving small intestinal submucosa (SIS) implants (Group 2, N = 4) or urethrotomy alone (Group 3, N = 3). Animals in all groups exhibited 100% survival prior to scheduled euthanasia and achieved voluntary voiding following 7 d of initial catheterization. Retrograde urethrography of each implant group at 3 m post-op revealed wide urethral calibers and preservation of organ continuity similar to pre-operative and urethrotomy controls with no evidence of contrast extravasation, strictures, fistulas, or stone formation. Histological (hematoxylin and eosin and Masson's trichrome), immunohistochemical, and histomorphometric analyses demonstrated that both silk fibroin and SIS scaffolds promoted similar extents of smooth muscle and epithelial tissue regeneration throughout the original defect sites with prominent contractile protein (α-smooth muscle actin and SM22α) and cytokeratin expression, respectively. De novo innervation and vascularization were also evident in all regenerated tissues indicated by synaptophysin-positive neuronal cells and vessels lined with CD31 expressing endothelial cells. Following 3 m post-op, minimal acute inflammatory reactions were elicited by silk fibroin scaffolds characterized by the presence of eosinophil granulocytes while SIS matrices promoted chronic inflammatory responses indicated by mobilization of mononuclear cell infiltrates. The results of this

  16. [Ganglia of peripheral nerves].

    PubMed

    Tatagiba, M; Penkert, G; Samii, M

    1993-01-01

    The authors present two different types of ganglion affecting the peripheral nerves: extraneural and intraneural ganglion. Compression of peripheral nerves by articular ganglions is well known. The surgical management involves the complete removal of the lesion with preservation of most nerve fascicles. Intraneural ganglion is an uncommon lesion which affects the nerve diffusely. The nerve fascicles are usually intimately involved between the cysts, making complete removal of all cysts impossible. There is no agreement about the best surgical management to be applied in these cases. Two possibilities are available: opening of the epineural sheath lengthwise and pressing out the lesion; or resection of the affected part of the nerve and performing a nerve reconstruction. While in case of extraneural ganglion the postoperative clinical evolution is very favourable, only long follow up studies will reveal in case of intraneural ganglion the best surgical approach. PMID:8128785

  17. Polymer scaffolds with preferential parallel grooves enhance nerve regeneration.

    PubMed

    Mobasseri, Atefeh; Faroni, Alessandro; Minogue, Ben M; Downes, Sandra; Terenghi, Giorgio; Reid, Adam J

    2015-03-01

    We have modified the surface topography of poly ɛ-caprolactone (PCL) and polylactic acid (PLA) blended films to improve cell proliferation and to guide the regeneration of peripheral nerves. Films with differing shaped grooves were made using patterned silicon templates, sloped walls (SL), V-shaped (V), and square-shaped (SQ), and compared with nongrooved surfaces with micropits. The solvent cast films were tested in vitro using adult adipose-derived stem cells differentiated to Schwann cell-like cells. Cell attachment, proliferation, and cell orientation were all improved on the grooved surfaces, with SL grooves giving the best results. We present in vivo data on Sprague-Dawley rat sciatic nerve injury with a 10-mm gap, evaluating nerve regeneration at 3 weeks across a polymer nerve conduit modified with intraluminal grooves (SL, V, and SQ) and differing wall thicknesses (70, 100, 120, and 210 μm). The SL-grooved nerve conduit showed a significant improvement over the other topographical-shaped grooves, while increasing the conduit wall thickness saw no positive effect on the biological response of the regenerating nerve. Furthermore, the preferred SL-grooved conduit (C) with 70 μm wall thickness was compared with the current clinical gold standard of autologous nerve graft (Ag) in the rat 10-mm sciatic nerve gap model. At 3 weeks postsurgery, all nerve gaps across both groups were bridged with regenerated nerve fibers. At 16 weeks, features of regenerated axons were comparable between the autograft (Ag) and conduit (C) groups. End organ assessments of muscle weight, electromyography, and skin reinnervation were also similar between the groups. The comparable experimental outcome between conduit and autograft, suggests that the PCL/PLA conduit with inner lumen microstructured grooves could be used as a potential alternative treatment for peripheral nerve repair. PMID:25435096

  18. Polymer Scaffolds with Preferential Parallel Grooves Enhance Nerve Regeneration

    PubMed Central

    Mobasseri, Atefeh; Faroni, Alessandro; Minogue, Ben M.; Downes, Sandra; Reid, Adam J.

    2015-01-01

    We have modified the surface topography of poly ɛ-caprolactone (PCL) and polylactic acid (PLA) blended films to improve cell proliferation and to guide the regeneration of peripheral nerves. Films with differing shaped grooves were made using patterned silicon templates, sloped walls (SL), V-shaped (V), and square-shaped (SQ), and compared with nongrooved surfaces with micropits. The solvent cast films were tested in vitro using adult adipose-derived stem cells differentiated to Schwann cell-like cells. Cell attachment, proliferation, and cell orientation were all improved on the grooved surfaces, with SL grooves giving the best results. We present in vivo data on Sprague-Dawley rat sciatic nerve injury with a 10-mm gap, evaluating nerve regeneration at 3 weeks across a polymer nerve conduit modified with intraluminal grooves (SL, V, and SQ) and differing wall thicknesses (70, 100, 120, and 210 μm). The SL-grooved nerve conduit showed a significant improvement over the other topographical-shaped grooves, while increasing the conduit wall thickness saw no positive effect on the biological response of the regenerating nerve. Furthermore, the preferred SL-grooved conduit (C) with 70 μm wall thickness was compared with the current clinical gold standard of autologous nerve graft (Ag) in the rat 10-mm sciatic nerve gap model. At 3 weeks postsurgery, all nerve gaps across both groups were bridged with regenerated nerve fibers. At 16 weeks, features of regenerated axons were comparable between the autograft (Ag) and conduit (C) groups. End organ assessments of muscle weight, electromyography, and skin reinnervation were also similar between the groups. The comparable experimental outcome between conduit and autograft, suggests that the PCL/PLA conduit with inner lumen microstructured grooves could be used as a potential alternative treatment for peripheral nerve repair. PMID:25435096

  19. Assessment of nerve morphology in nerve activation during electrical stimulation

    NASA Astrophysics Data System (ADS)

    Gomez-Tames, Jose; Yu, Wenwei

    2013-10-01

    The distance between nerve and stimulation electrode is fundamental for nerve activation in Transcutaneous Electrical Stimulation (TES). However, it is not clear the need to have an approximate representation of the morphology of peripheral nerves in simulation models and its influence in the nerve activation. In this work, depth and curvature of a nerve are investigated around the middle thigh. As preliminary result, the curvature of the nerve helps to reduce the simulation amplitude necessary for nerve activation from far field stimulation.

  20. Osteogenesis effect of guided bone regeneration combined with alveolar cleft grafting: assessment by cone beam computed tomography.

    PubMed

    Xiao, W-L; Zhang, D-Z; Chen, X-J; Yuan, C; Xue, L-F

    2016-06-01

    Cone beam computed tomography (CBCT) allows for a significantly lower radiation dose than conventional computed tomography (CT) scans and provides accurate images of the alveolar cleft area. The osteogenic effect of guided bone regeneration (GBR) vs. conventional alveolar bone grafting alone for alveolar cleft defects was evaluated in this study. Sixty alveolar cleft patients were divided randomly into two groups. One group underwent GBR using acellular dermal matrix film combined with alveolar bone grafting using iliac crest bone grafts (GBR group), while the other group underwent alveolar bone grafting only (non-GBR group). CBCT images were obtained at 1 week and at 3 months following the procedure. Using Simplant 11.04 software, the bone resorption rate was calculated and compared between the two groups. The bone resorption rate from 1 week to 3 months following bone grafting without the GBR technique was 36.50±5.04%, whereas the bone resorption rate using the GBR technique was 31.69±5.50% (P=0.017). The application of autogenous iliac bone combined with the GBR technique for alveolar bone grafting of alveolar cleft patients can reduce bone resorption and result in better osteogenesis. PMID:26876144

  1. Phrenic and diaphragm function after coronary artery bypass grafting.

    PubMed Central

    Estenne, M; Yernault, J C; De Smet, J M; De Troyer, A

    1985-01-01

    We studied respiratory mechanics and phrenic nerve and diaphragm function in 12 patients on the day before and eight to 13 days after coronary artery bypass grafting. The average vital capacity, functional residual capacity, and total lung capacity decreased by 20.5%, 9.5%, and 14.7% respectively after operation. Eleven patients showed less negative maximum inspiratory mouth pressures at any given lung volume after surgery and the magnitude of the change correlated with the reduction in total lung capacity. In 11 of the 12 patients the conduction times of the right and left phrenic nerves did not change substantially after operation and the ratio of inspiratory electrical activity (Edi) of left and right hemidiaphragms was similar before and after the procedure. One patient, however, showed a considerable increase in left phrenic nerve conduction time and a reduction in the left to right Edi ratio postoperatively. In three patients diaphragm function was also assessed by changes in transdiaphragmatic pressure during supramaximal phrenic nerve stimulation and voluntary increase in inspired volume; in none of the three patients did the transdiaphragmatic pressure swings show any significant change in the postoperative period. These data indicate that phrenic nerve paralysis only occasionally accounts for the postoperative loss of lung volume after coronary artery bypass grafting surgery. The mechanism of these abnormalities therefore remains to be determined. PMID:3875161

  2. Florid pustular dermatitis of breast: A case report on a unusual complication from acellular dermal matrix use

    PubMed Central

    James, Justin; Jackson, Lee; Saunders, Christobel

    2016-01-01

    Introduction Idiopathic erythematous reaction of the breast (Red breast syndrome) is a known complication following breast reconstruction with acellular dermal matrix. However pustular dermatitis like presentation is not previously known. Presentation of case We present a 42-year-old lady who developed bilateral pustular dermatitis like appearance following breast reconstruction with acellular dermal matrix slings. Though surgical washout was done, both expanders and flex HD could be preserved. Discussion Acellular dermal matrix use is the only possible explanation for such a presentation and this can be considered a variant of red breast syndrome. Conclusion Pustular dermatitis like presentation can be associated with acelluar dermal matrix use and should be considered in similar clinical presentations, since this can avoid unnecessary surgical procedures. PMID:27058152

  3. AB023. Penile augmentation surgery: characteristics of artificial graft material and preoperative preparation

    PubMed Central

    Lee, Woong Hee

    2015-01-01

    Penile augmentation surgical procedure includes diverse graft materials such as artificial collagen material as well as dermo-fat graft. Important factors of postoperative satisfaction are natural appearance of genitalia at the flaccid state and minimal resorption of graft volume. Artificial collagen materials and acellular dermal matrix are available for surgical procedure with variable size. History of penile augmentation surgery: Pediatric penile surgical procedure for lengthening and reconstructive surgery was developed as penile plastic surgical procedure combined with dermo-fat graft. In 1971, Kelly, Eraklis et al. reported preservation of dorsal neurovascular bundle and division of corporal crus from ischiopubic ramus for penile lengthening procedure. In 1974, Johnson reported the surgical cases in epispadias patient as division of crus from ischiopubic ramus and penile skin graft. The procedures include division of suspensory ligament and blunt dissection of fundiform ligament. In 1970’s Horton reported suprapubic fat resection and Z-plasty with anchoring on Scarpa’s fascia for lengthening procedure. In 1980’s several fat injection procedures in Darto’s fascia have been reported for girth enhancement but they were lack of reproducibility. (1year Resorption 50%) Later reports the result of cystic nodule, lump formation and fat migration. In 1990’s V-Y plasty for lengthening was reported. Historically illegal liquid injection materials with non-medical hands were reported as correction or reconstructive procedures for removal and treatment of deformed genitalia. In 1992 Horton reported flank abdominal free dermo-fat graft to Darto’s fascia. This procedure showed fair graft survival rate and developed to buttock skin crease dermo-fat graft. Medical grade silicone; long-term implantable; Gortex plate, polytetrafluoroethylene (PTFE); Acelluar dermal graft/(Alloderm, Surederm); Acellular xenogeniccollagen structure/(Lyoplant, Terudermis); Autologous

  4. Constructing Human Skin Equivalents on Porcine Acellular Peritoneum Extracellular Matrix for In Vitro Irritation Testing.

    PubMed

    Tsai, Pei-Chin; Zhang, Zheng; Florek, Charles; Michniak-Kohn, Bozena B

    2016-01-01

    The irritancy of topical products has to be investigated to ensure the safety and compliance. Although several reconstructed human epidermal models have been adopted by the Organization for Economic Cooperation and Development (OECD) to replace in vivo animal irritation testing, these models are based on a single cell type and lack dermal components, which may be insufficient to reflect all of the components of irritation. In our study, we investigated the use of acellular porcine peritoneum extracellular matrix as a substrate to construct full-thickness human skin equivalents (HSEs) for use as irritation screening tool. The acellular peritoneum matrix (APM) exhibited excellent skin cell attachment (>80%) and proliferation for human dermal fibroblasts (HDF) and immortalized human keratinocytes (HaCaT). APM-HSEs based on coculture of HDF and HaCaT were prepared. Increased HDF seeding density up to 5 × 10(4)/cm(2) resulted in APM-HSEs with a thicker and more organized epidermis. The epidermis of APM-HSEs expressed keratin 15, a keratinocyte proliferation marker, and involucrin, a differentiation marker, respectively. To assess the use of APM-HSEs for irritation testing, six proficiency chemicals, including three nonirritants (phosphate-buffered saline, polyethylene glycol 400, and isopropanol) and three irritants (1-bromohexane, heptanol, and sodium dodecyl sulfate) were applied. The APM-HSEs were able to discriminate nonirritants from irritants based on the viability. Levels of cytokines (interleukin [IL]-1α, IL-1ra, IL-6, IL-8, and granulocyte macrophage colony-stimulating factor [GM-CSF]) in these treatment groups further assisted the irritancy ranking. In conclusion, we have developed partially differentiated full-thickness APM-HSEs based on acellular porcine peritoneum matrix, and these APM-HSEs demonstrated utility as an in vitro irritation screening tool. PMID:26415037

  5. The Human Umbilical Vein with Wharton's Jelly as an Allogeneic, Acellular Construct for Vocal Fold Restoration

    PubMed Central

    Rodriguez, Maritza L.; McFetridge, Peter S.

    2009-01-01

    This study investigated the potential of the decellularized human umbilical vein (HUV) as an allogeneic, acellular extracellular matrix (ECM) scaffold for engineering the vocal fold lamina propria in vitro. HUV specimens with Wharton's jelly on the abluminal surface were uniformly dissected from native umbilical cords using an automated procedure and subjected to a novel saline-based decellularization treatment for removal of potentially antigenic epitopes. Human vocal fold fibroblasts from primary culture were seeded onto the resulting acellular constructs and cultured for 21 days. The structures of decellularized and fibroblast-repopulated HUV constructs and the attachment, proliferation, and infiltration of fibroblasts were examined with light microscopy and scanning electron microscopy. Changes in the relative densities of collagen in the constructs associated with decellularization and recellularization were quantified using digital image analysis. In addition, fibroblasts infiltrating the scaffolds were released by cell recovery and quantified by counting. Viscoelastic properties of the scaffolds were measured using a linear, simple-shear rheometer at phonatory frequencies. Results showed that an acellular ECM construct with an intact three-dimensional structure of Wharton's jelly was fabricated. Vocal fold fibroblasts readily attached on the abluminal surface of the construct with high viability, with significant cellular infiltration up to approximately 600 μm deep into the construct. A significant increase in collagen expression was observed with recellularization. The elastic modulus and dynamic viscosity of the fibroblast-repopulated scaffolds were comparable to those of the human vocal fold lamina propria. These findings supported the potential of the construct as a possible surgical allograft for vocal fold restoration and reconstruction. PMID:19456236

  6. Current opinions on indications and algorithms for acellular dermal matrix use in primary prosthetic breast reconstruction.

    PubMed

    Vu, Michael M; Kim, John Y S

    2015-06-01

    Acellular dermal matrix (ADM) is widely used in primary prosthetic breast reconstruction. Many indications and contraindications to use ADM have been reported in the literature, and their use varies by institution and surgeon. Developing rational, tested algorithms to determine when ADM is appropriate can significantly improve surgical outcomes and reduce costs associated with ADM use. We review the important indications and contraindications, and discuss the algorithms that have been put forth so far. Further research into algorithmic decision-making for ADM use will allow optimized balancing of cost with risk and benefit. PMID:26161304

  7. Mechanisms by which acellular biologic scaffolds promote functional skeletal muscle restoration.

    PubMed

    Badylak, Stephen F; Dziki, Jenna L; Sicari, Brian M; Ambrosio, Fabrisia; Boninger, Michael L

    2016-10-01

    Acellular biologic scaffolds derived from extracellular matrix have been investigated in preclinical and clinical studies as a regenerative medicine approach for volumetric muscle loss treatment. The present manuscript provides a review of previous studies supporting the use of extracellular matrix derived biologic scaffolds for the promotion of functional skeletal muscle tissue formation that is contractile and innervated. The manuscript also identifies key mechanisms that have been associated with ECM-mediated skeletal muscle repair, and provides hypotheses as to why there have been variable outcomes, ranging from successful to unsatisfactory, associated with ECM bioscaffold implantation in the skeletal muscle injury microenvironment. PMID:27376561

  8. Chronic Posttraumatic Dislocation of Radial Head With Ulnar Nerve Entrapment in a Child: A Case Report and Literature Review.

    PubMed

    Cai, Jiangyu; Wang, Wei; Yu, Shiyang; Yan, Hede; Zhan, Yulin; Fan, Cunyi

    2016-06-01

    We present an unusual case of chronic posttraumatic anteromedial dislocation of radial head with direct ulnar nerve entrapment in a child. Ulnar nerve decompression, open reduction of the radial head, and annular ligament reconstruction using a palmaris longus tendon graft were performed, and a satisfactory functional outcome was achieved at the 15-month follow-up. Through a review of literature, we conclude that early diagnosis and management for radial head dislocation are recommended to avoid nerve symptoms. Besides, open reduction and annular ligament reconstruction with a palmaris longus tendon graft would be an alternative surgery during chronic phase. PMID:27171922

  9. The Furcal Nerve Revisited

    PubMed Central

    Dabke, Harshad V.

    2014-01-01

    Atypical sciatica and discrepancy between clinical presentation and imaging findings is a dilemma for treating surgeon in management of lumbar disc herniation. It also constitutes ground for failed back surgery and potential litigations thereof. Furcal nerve (Furcal = forked) is an independent nerve with its own ventral and dorsal branches (rootlets) and forms a link nerve that connects lumbar and sacral plexus. Its fibers branch out to be part of femoral and obturator nerves in-addition to the lumbosacral trunk. It is most commonly found at L4 level and is the most common cause of atypical presentation of radiculopathy/sciatica. Very little is published about the furcal nerve and many are unaware of its existence. This article summarizes all the existing evidence about furcal nerve in English literature in an attempt to create awareness and offer insight about this unique entity to fellow colleagues/professionals involved in spine care. PMID:25317309

  10. Sciatic nerve injection injury.

    PubMed

    Jung Kim, Hyun; Hyun Park, Sang

    2014-06-11

    Nerve injury is a common complication following intramuscular injection and the sciatic nerve is the most frequently affected nerve, especially in children, the elderly and underweight patients. The neurological presentation may range from minor transient pain to severe sensory disturbance and motor loss with poor recovery. Management of nerve injection injury includes drug treatment of pain, physiotherapy, use of assistive devices and surgical exploration. Early recognition of nerve injection injury and appropriate management are crucial in order to reduce neurological deficit and to maximize recovery. Sciatic nerve injection injury is a preventable event. Total avoidance of intramuscular injection is recommended if other administration routes can be used. If the injection has to be administered into the gluteal muscle, the ventrogluteal region (gluteal triangle) has a more favourable safety profile than the dorsogluteal region (the upper outer quadrant of the buttock). PMID:24920643

  11. Effect of concurrent mental nerve reconstruction at the same time as mandibular reconstruction using a fibula osteoseptocutaneous flap.

    PubMed

    Shimizu, Fumiaki; Ooatari, Miwako; Uehara, Miyuki; Takahashi, Yoshihiro; Kawano, Kenji

    2015-09-01

    The damage of inferior alveolar nerve causes some functional problem including numbness of lower lip and drooling. During segmental mandibulectomy, inferior alveolar nerve commonly resected, therefore, it is ideal to reconstruct the nerve to get better functional result. Sensory recovery was assessed after mandibular reconstruction using free fibula osteoseptocutaneous flap in thirteen cases. In six cases, the mental nerve reconstruction was performed simultaneously, and in seven cases, the mental nerve reconstruction was not performed. In the case that the mental nerve was reconstructed simultaneously, unilateral mental nerve reconstruction was performed in five cases, and bilateral mental nerve reconstruction was performed in one cases. More than one year after the reconstruction, sensory recovery was assessed and compared between the group that the mental nerve was reconstructed and the group that was not reconstructed. Our results showed almost a normal sensory recovery of the lips on the reconstructed side more than one year after the reconstruction in reconstructed group. In contrast, sensory recovery was poor in non-reconstructed group and non-reconstructed side. These results showed that mental nerve reconstruction at the same time as mandibular reconstruction affects the postoperative mandibular function. The sural nerve can be harvested from the same donor site of the free fibula osteoseptocutaneous flap and such mental nerve reconstruction with nerve grafting can be completed within an hour. Most cases of mandibular reconstruction using a free fibula osteoseptocutaneous flap transfer can therefore be candidates for mental nerve reconstruction at the time of mandibular reconstruction. PMID:26051850

  12. Endoscopic Facial Nerve Surgery.

    PubMed

    Marchioni, Daniele; Soloperto, Davide; Rubini, Alessia; Nogueira, João Flávio; Badr-El-Dine, Mohamed; Presutti, Livio

    2016-10-01

    Tympanic facial nerve segment surgery has been traditionally performed using microscopic approaches, but currently, exclusive endoscopic approaches have been performed for traumatic, neoplastic, or inflammatory diseases, specially located at the geniculate ganglion, greater petrosal nerve, and second tract of the facial nerve, until the second genu. The tympanic segment of the facial nerve can be reached and visualized using an exclusive transcanal endoscopic approach, even in poorly accessible regions such as the second genu and geniculate ganglion, avoiding mastoidectomy, bony demolition, and meningeal or cerebral lobe tractions, with low complication rates using a minimally invasive surgical route. PMID:27468633

  13. Biology of cancellous bone grafts.

    PubMed

    Heiple, K G; Goldberg, V M; Powell, A E; Bos, G D; Zika, J M

    1987-04-01

    Despite 30 years of experimental bone grafting research, the fresh cancellous bone graft remains the most osteogenic and reliable bone grafting material. Recent experimental data suggest that modification of the graft-host interaction by antigen matching or immune manipulation may allow increasingly successful use of allografts. PMID:3550570

  14. Aseptic versus Sterile Acellular Dermal Matrices in Breast Reconstruction: An Updated Review

    PubMed Central

    Mendenhall, Shaun D.; Neumeister, Michael W.; Cederna, Paul S.; Momoh, Adeyiza O.

    2016-01-01

    Background: As the use of acellular dermal matrices in breast reconstruction has become more commonplace and efforts are made to improve on postoperative outcomes, the method of acellular dermal matrix (ADM) processing (aseptic versus sterile) has become a subject of interest. This article provides an updated overview of the critical aspects of ADM processing in addition to application of ADMs in single- and two-stage breast reconstruction, a review of the morbidity associated with ADM use, and alternatives. Methods: A literature review was performed in PubMed identifying recent systematic reviews, meta-analyses, and head-to-head comparisons on aseptically processed ADM and sterile-processed ADM in implant-based breast reconstruction. Results: Recent meta-analyses have shown a 2- to 3-fold increase in infections and tissue expander/implant explantation rates and a 3- to 4-fold increase in seroma formation compared with non-ADM reconstruction techniques. Comparisons of aseptic and sterile ADMs in multiple studies have shown no significant difference in infection rates and equivocal findings for other specific complications such as seroma formation. Conclusions: Current evidence on the impact of processing techniques that improve ADM sterility on postoperative morbidity in implant breast reconstruction is unclear. Deficiencies of the available data highlight the need for well-designed, multicenter, randomized controlled studies that will aid in optimizing outcomes in implant-based breast reconstruction. PMID:27536502

  15. Screening for Oxidative Stress Elicited by Engineered Nanomaterials: Evaluation of Acellular DCFH Assay

    PubMed Central

    Pal, Anoop K.; Bello, Dhimiter; Budhlall, Bridgette; Rogers, Eugene; Milton, Donald K.

    2012-01-01

    The DCFH assay is commonly used for measuring free radicals generated by engineered nanomaterials (ENM), a well-established mechanism of ENM toxicity. Concerns exist over susceptibility of the DCFH assay to: assay conditions, adsorption of DCFH onto ENM, fluorescence quenching and light scattering. These effects vary in magnitude depending on ENM physiochemical properties and concentration. A rigorous evaluation of this method is still lacking. The objective was to evaluate performance of the DCFH assay for measuring ENM-induced free radicals. A series of diverse and well-characterized ENM were tested in the acellular DCFH assay. We investigated the effect of sonication conditions, dispersion media, ENM concentration, and the use of horseradish peroxidase (HRP) on the DCFH results. The acellular DCFH assay suffers from high background signals resulting from dye auto-oxidation and lacks sensitivity and robustness. DCFH oxidation is further enhanced by HRP. The number of positive ENM in the assay and their relative ranking changed as a function of experimental conditions. An inverse dose relationship was observed for several Carbon-based ENM. Overall, these findings indicate the importance of having standardized assays for evaluating ENM toxicity and highlights limitations of the DCFH assay for measuring ENM-induced free radicals. PMID:22942866

  16. Deficiency in acellular cementum and periodontal attachment in bsp null mice.

    PubMed

    Foster, B L; Soenjaya, Y; Nociti, F H; Holm, E; Zerfas, P M; Wimer, H F; Holdsworth, D W; Aubin, J E; Hunter, G K; Goldberg, H A; Somerman, M J

    2013-02-01

    Bone sialoprotein (BSP) is an extracellular matrix protein found in mineralized tissues of the skeleton and dentition. BSP is multifunctional, affecting cell attachment and signaling through an RGD integrin-binding region, and acting as a positive regulator for mineral precipitation by nucleating hydroxyapatite crystals. BSP is present in cementum, the hard tissue covering the tooth root that anchors periodontal ligament (PDL) attachment. To test our hypothesis that BSP plays an important role in cementogenesis, we analyzed tooth development in a Bsp null ((-/-)) mouse model. Developmental analysis by histology, histochemistry, and SEM revealed a significant reduction in acellular cementum formation on Bsp (-/-) mouse molar and incisor roots, and the cementum deposited appeared hypomineralized. Structural defects in cementum-PDL interfaces in Bsp (-/-) mice caused PDL detachment, likely contributing to the high incidence of incisor malocclusion. Loss of BSP caused progressively disorganized PDL and significantly increased epithelial down-growth with aging. Bsp (-/-) mice displayed extensive root and alveolar bone resorption, mediated by increased RANKL and the presence of osteoclasts. Results collected here suggest that BSP plays a non-redundant role in acellular cementum formation, likely involved in initiating mineralization on the root surface. Through its importance to cementum integrity, BSP is essential for periodontal function. PMID:23183644

  17. Sterile acellular dermal collagen as a treatment for rippling deformity of breast.

    PubMed

    Busse, Brittany; Orbay, Hakan; Sahar, David E

    2014-01-01

    Prosthetic implants are frequently used for breast augmentation and breast reconstruction following mastectomy. Unfortunately, long-term aesthetic results of prosthetic breast restoration may be hindered by complications such as rippling, capsular contracture, and implant malposition. The advent of use of acellular dermal matrices has greatly improved the outcomes of prosthetic breast reconstruction. We describe a case of rippling deformity of breast that was treated using an acellular dermal matrix product, AlloMax. The patient presented with visible rippling of bilateral prosthetic breast implants as well as significant asymmetry of the breasts after multiple excisional biopsies for right breast ductal carcinoma in situ. A 6 × 10 cm piece of AlloMax was placed on the medial aspect of each breast between the implant and the skin flap. Follow-up was performed at 1 week, 3 months, and 1 year following the procedure. The patient recovered well from the surgery and there were no complications. At her first postoperative follow-up the patient was extremely satisfied with the result. At her 3-month and 1-year follow-up she had no recurrence of her previous deformity and no new deformity. PMID:25610697

  18. Alternatives to HIST for acellular pertussis vaccines: progress and challenges in replacement

    PubMed Central

    Arciniega, J.; Wagner, L.; Prymula, R.; Sebo, P.; Isbrucker, R.; Descampe, B.; Chapsal, J.M.; Costanzo, A.; Hendriksen, C.; Hoonaker, M.; Nelson, S.; Lidster, K.; Casey, W.; Allen, D.

    2016-01-01

    The ‘International Workshop on Alternatives to the Murine Histamine Sensitization Test for Acellular Pertussis Vaccines: Progress and Challenges in the Replacement of HIST’ was held on 24 August 2014, in Prague, Czech Republic, as a satellite meeting to the 9 th World Congress on Alternatives and Animal Use in the Life Sciences. Participants discussed the progress and challenges associated with the development, validation, and implementation of in vitro assays as replacements for the histamine sensitisation test (HIST) for acellular pertussis vaccines. Discussions focused on the consistency approach, the necessary framework for regulatory acceptance of a harmonised method, and recent international efforts towards the development of in vitro assays to replace the HIST. Workshop participants agreed that acceptable alternatives to the HIST should be based on ADP ribosylation-mediated cell intoxication and therefore that the CHO cell clustering assay, which measures cell intoxication, should be further pursued and developed as a possible replacement for the HIST. Participants also agreed to continue ongoing multinational discussions involving national and international standardisation authorities to reach consensus and to organise collaborative studies in this context for assay characterisation and calibration of reference materials. PMID:27506225

  19. Multiplex immunoassay for in vitro characterization of acellular pertussis antigens in combination vaccines.

    PubMed

    Agnolon, Valentina; Bruno, Cristina; Galletti, Bruno; Mori, Elena; Ugozzoli, Mildred; Pergola, Carlo; O'Hagan, Derek T; Baudner, Barbara C

    2016-02-17

    Vaccines characterization is required to ensure physical, chemical, and biological integrity of antigens and adjuvants. Current analytical methods mostly require complete antigen desorption from aluminum-based adjuvants and are not always suitable to distinguish individual antigens in multivalent formulations. Here, Luminex technology is proposed to improve the analytics of vaccine characterization. As proof of concept, TdaP (tetanus, diphtheria and acellular pertussis) combination, adjuvanted with aluminum hydroxide, was chosen as model formulation to quantify and determine the level of adsorption of acellular pertussis (aP) antigens onto adjuvant surface at the same time. The assay used specific antibodies bound to magnetic microspheres presenting unique digital signatures for each pertussis antigen, allowing the simultaneous recognition of respective antigens in the whole vaccine, avoiding laborious procedures for adjuvant separation. Accurate and reproducible quantification of aP antigens in TdaP vaccine has been achieved in the range 0.78-50 ng/mL, providing simultaneously information on antigen identity, quantity, and degree of adsorption to aluminum hydroxide. The current study could further be considered as a model to set up in vitro potency assays thus supporting the replacement of animal tests accordingly to the 3Rs concept. PMID:26784684

  20. Brachial Plexopathy/Nerve Root Avulsion in a Football Player: The Role of Electrodiagnostics

    PubMed Central

    Radecki, Jeffrey; Wolfe, Scott W.; Strauss, Helene L.; Mintz, Douglas N.

    2008-01-01

    Electromyography (EMG) studies are a useful tool in anatomical localization of peripheral nerve and brachial plexus injuries. They are especially helpful in distinguishing between brachial plexopathy and nerve root injuries where surgical intervention may be indicated. EMG can also assist in providing prognostic information after nerve injury as well as after nerve repair. In this case report, a football player presented with weakness in his right upper limb after a traction/traumatic injury to the right brachial plexus. EMG studies revealed evidence of both pre- and postganglionic injury to multiple cervical roots. The injury was substantial enough to cause nerve root avulsions involving the C6 and C7 levels. Surgical referral led to nerve grafts targeted at regaining function in shoulder abduction and elbow flexion. After surgery, the patient’s progress was monitored utilizing EMG to assist in identifying true axonal regeneration. PMID:18751870

  1. [Neurons with Different Neurotransmitters in Embryonic Neocortical Allografts in the Rat Sciatic Nerve].

    PubMed

    Petrova, E S

    2016-01-01

    Different subsets of interneurons in the Wistar rat neocortex and in neocortical transplants developing in a damaged nerve were identified by the following immunohistochemical markers: glutamate decarboxylase (GAD 67) for GABAergic nerve cells, NO-synthase (NOS) for NO-ergic neurons, choline acetyltransferase (ChAT) for cholinergic cells, and tyrosine hydroxylase for catecholaminergic structures. Twenty-eight days after surgery, individual GAD 67-ir, NO-ir, ChAT-ir, and very rarely TH-ir cells were detected in the graft. It was shown that the number of GAD 67-ir neurons per unit area in the grafts was less than in the rat neocortex P20. PMID:27396173

  2. Proximal Tibial Bone Graft

    MedlinePlus

    ... Complications Potential problems after a PTBG include infection, fracture of the proximal tibia and pain related to the procedure. Frequently Asked Questions If proximal tibial bone graft is taken from my knee, will this prevent me from being able to ...

  3. Epidermal skin grafting.

    PubMed

    Herskovitz, Ingrid; Hughes, Olivia B; Macquhae, Flor; Rakosi, Adele; Kirsner, Robert

    2016-09-01

    Autologous skin grafts, such as full- and split-thickness, have long been part of the reconstructive ladder as an option to close skin defects. Although they are effective in providing coverage, they require the need for a trained surgeon, use of anaesthesia and operating room and creation of a wound at the donor site. These drawbacks can be overcome with the use of epidermal skin grafts (ESGs), which can be harvested without the use of anaesthesia in an office setting and with minimal to no scarring at the donor site. ESGs consist only of the epidermal layer and have emerged as an appealing alternative to other autologous grafts for the treatment of acute and chronic wounds. In this article, we provide an overview of epidermal grafting and its role in wound management. PMID:27547964

  4. Sizing of crimped Dacron grafts.

    PubMed

    Reid, J D; Sladen, J G

    1992-05-01

    The aim of this study was to correlate the stated size of Dacron grafts (Microvel) with their actual internal diameter and to compare this with measurements by ultrasound in the early postoperative period. Grafts of stated diameters of 7, 8, 9, and 10 mm were studied. Grafts were measured by graded probes and by measuring the width of the longitudinally opened graft and calculating the diameter. Each graft accepted a probe 1 mm larger than its stated size very easily and 2 mm greater when stretched. By open measurement, the grafts were 1.3 to 1.8 mm greater than their stated diameter without stretching. Twenty grafts were studied by duplex ultrasound for diameter and peak systolic velocity within 3 months of implantation. The grafts were 12% larger than their stated graft size. Some of the larger grafts showed low velocity and wall thrombus. We conclude that Microvel grafts are larger than their stated diameter. The same size discrepancy was seen in in vitro measurements of Vascutek (Dacron) grafts but not in polytetrafluoroethylene (Gortex) grafts. Since flow velocity is related to the diameter of the graft, this information should be useful when choosing the diameter of a prosthetic vascular graft. PMID:1533494

  5. [Zaidemberg's vascularized radial graft].

    PubMed

    Saint-Cast, Y

    2010-12-01

    In 1991, Carlos Zaidemberg described a new technique to repair scaphoid non-unions with a vascularized bone graft harvested from the radial styloid process. An anatomic study based on 30 dissections after colorized latex injection established the constancy of the radial styloid process's artery, while showing that its origin, course and length were subject to variations. In a retrospective series of 38 cases over a period of 10 years, the vascularized bone graft was indicated for: (1) scaphoid non-union with the presence of avascular changes of the proximal fragment (23 cases); (2) failed prior reconstruction with bone graft and internal fixation (nine cases); (3) degenerative styloid-scaphoid arthritis (three cases); (4) fracture on Preiser dystrophy (three cases). The five steps of the simplified operative technique without dissection of the vascular pedicle include: (1) longitudinal dorso-radial approach, identification of the periosteal portion of the radial styloid process artery; (2) incision of the first and second compartments, longitudinal arthrotomy under the second compartment; (3) styloidectomy and transversal resection of the scaphoid non-union and sclerotic bone; (4) elevation of the vascularized bone graft; (5) transversal and radial insertion of the vascularized bone graft, osteosynthesis by two or three K-wire touching the scaphoid's radial edge. Scaphoid union was obtained in 33 cases out of 38. The only postoperative complications were two transient radial paresthesia. The standardized surgical procedure using vascularized bone graft harvested from the radial styloid process provides an efficient scaphoid reconstruction. PMID:21087882

  6. Intraoperative vagal nerve monitoring.

    PubMed

    Leonetti, J P; Jellish, W S; Warf, P; Hudson, E

    1996-08-01

    A variety of benign and malignant neoplasms occur in the superior cervical neck, parapharyngeal space or the infratemporal fossa. The surgical resection of these lesions may result in postoperative iatrogenic injury to the vagus nerve with associated dysfunctional swallowing and airway protection. Anatomic and functional preservation of this critical cranial nerve will contribute to a favorable surgical outcome. Fourteen patients with tumors of the cervical neck or adjacent skull base underwent intraoperative vagal nerve monitoring in an attempt to preserve neural integrity following tumor removal. Of the 11 patients with anatomically preserved vagal nerves in this group, seven patients had normal vocal cord mobility following surgery and all 11 patients demonstrated normal vocal cord movement by six months. In an earlier series of 23 patients with tumors in the same region who underwent tumor resection without vagal nerve monitoring, 18 patients had anatomically preserved vagal nerves. Within this group, five patients had normal vocal cord movement at one month and 13 patients demonstrated normal vocal cord movement at six months. This paper will outline a technique for intraoperative vagal nerve monitoring utilizing transcricothyroid membrane placement of bipolar hook-wire electrodes in the vocalis muscle. Our results with the surgical treatment of cervical neck and lateral skull base tumors for patients with unmonitored and monitored vagal nerves will be outlined. PMID:8828272

  7. Inferior alveolar nerve repositioning.

    PubMed

    Louis, P J

    2001-09-01

    Nerve repositioning is a viable alternative for patients with an atrophic edentulous posterior mandible. Patients, however, should be informed of the potential risks of neurosensory disturbance. Documentation of the patient's baseline neurosensory function should be performed with a two-point discrimination test or directional brush stroke test preoperatively and postoperatively. Recovery of nerve function should be expected in 3 to 6 months. The potential for mandibular fracture when combining nerve repositioning with implant placement also should be discussed with the patient. This can be avoided by minimizing the amount of buccal cortical plate removal during localization of the nerve and maintaining the integrity of the inferior cortex of the mandible. Additionally, avoid overseating the implant, thus avoiding stress along the inferior border of the mandible. The procedure does allow for the placement of longer implants, which should improve implant longevity. Patients undergoing this procedure have expressed overall satisfaction with the results. Nerve repositioning also can be used to preserve the inferior alveolar nerve during resection of benign tumors or cysts of the mandible. This procedure allows the surgeon to maintain nerve function in situations in which the nerve would otherwise have to be resected. PMID:11665379

  8. Distal median nerve dysfunction

    MedlinePlus

    ... Names Neuropathy - distal median nerve Images Central nervous system and peripheral nervous system References Jarvik JG, Comstock BA, Kliot M, et al. Surgery versus non-surgical therapy for carpal tunnel syndrome: a randomized ... D. Disorders of peripheral nerves. In: Daroff RB, Fenichel GM, Jankovic J, ...

  9. Optic Nerve Decompression

    MedlinePlus

    ... canals). The optic nerve is the “nerve of vision” and extends from the brain, through your skull, and into your eye. A ... limited to, the following: loss of vision, double vision, inadequate ... leakage of brain fluid (CSF), meningitis, nasal bleeding, infection of the ...

  10. Sensory Recovery Outcome after Digital Nerve Repair in Relation to Different Reconstructive Techniques: Meta-Analysis and Systematic Review

    PubMed Central

    Wolf, Petra; Harder, Yves; Kern, Yasmin; Paprottka, Philipp M.; Machens, Hans-Günther; Lohmeyer, Jörn A.

    2013-01-01

    Good clinical outcome after digital nerve repair is highly relevant for proper hand function and has a significant socioeconomic impact. However, level of evidence for competing surgical techniques is low. The aim is to summarize and compare the outcomes of digital nerve repair with different methods (end-to-end and end-to-side coaptations, nerve grafts, artificial conduit-, vein-, muscle, and muscle-in-vein reconstructions, and replantations) to provide an aid for choosing an individual technique of nerve reconstruction and to create reference values of standard repair for nonrandomized clinical studies. 87 publications including 2,997 nerve repairs were suitable for a precise evaluation. For digital nerve repairs there was practically no particular technique superior to another. Only end-to-side coaptation had an inferior two-point discrimination in comparison to end-to-end coaptation or nerve grafting. Furthermore, this meta-analysis showed that youth was associated with an improved sensory recovery outcome in patients who underwent digital replantation. For end-to-end coaptations, recent publications had significantly better sensory recovery outcomes than older ones. Given minor differences in outcome, the main criteria in choosing an adequate surgical technique should be gap length and donor site morbidity caused by graft material harvesting. Our clinical experience was used to provide a decision tree for digital nerve repair. PMID:23984064

  11. Management of Facial Nerve in Surgical Treatment of Previously Untreated Fisch Class C Tympanojugular Paragangliomas: Long-Term Results

    PubMed Central

    Bacciu, Andrea; Ait Mimoune, Hassan; D'Orazio, Flavia; Vitullo, Francesca; Russo, Alessandra; Sanna, Mario

    2013-01-01

    The aim of this study was to evaluate the long-term facial nerve outcome according to management of the facial nerve in patients undergoing surgery for Fisch class C tympanojugular paragangliomas. The study population consisted of 122 patients. The infratemporal type A approach was the most common surgical procedure. The facial nerve was left in place in 2 (1.6%) of the 122 patients, anteriorly rerouted in 97 (79.5%), anteriorly rerouted with segmental resection of the epineurium in 7 (5.7%), and sacrificed and reconstructed in 15 (12.3%). One patient underwent cross-face nerve grafting. At last follow-up, House-Brackmann grade I to II was achieved in 51.5% of patients who underwent anterior rerouting and in 28.5% of those who underwent anterior rerouting with resection of the epineurium. A House-Brackmann grade III was achieved in 73.3% of patients who underwent cable nerve graft interposition. The two patients in whom the facial nerve was left in place experienced grade I and grade III, respectively. The patient who underwent cross-face nerve grafting had grade III. Gross total resection was achieved in 105 cases (86%). Management of the facial nerve in tympanojugular paraganglioma surgery can be expected to ensure satisfactory facial function long-term outcome. PMID:24498582

  12. Preoperative transcutaneous electrical nerve stimulation for localizing superficial nerve paths.

    PubMed

    Natori, Yuhei; Yoshizawa, Hidekazu; Mizuno, Hiroshi; Hayashi, Ayato

    2015-12-01

    During surgery, peripheral nerves are often seen to follow unpredictable paths because of previous surgeries and/or compression caused by a tumor. Iatrogenic nerve injury is a serious complication that must be avoided, and preoperative evaluation of nerve paths is important for preventing it. In this study, transcutaneous electrical nerve stimulation (TENS) was used for an in-depth analysis of peripheral nerve paths. This study included 27 patients who underwent the TENS procedure to evaluate the peripheral nerve path (17 males and 10 females; mean age: 59.9 years, range: 18-83 years) of each patient preoperatively. An electrode pen coupled to an electrical nerve stimulator was used for superficial nerve mapping. The TENS procedure was performed on patients' major peripheral nerves that passed close to the surgical field of tumor resection or trauma surgery, and intraoperative damage to those nerves was apprehensive. The paths of the target nerve were detected in most patients preoperatively. The nerve paths of 26 patients were precisely under the markings drawn preoperatively. The nerve path of one patient substantially differed from the preoperative markings with numbness at the surgical region. During surgery, the nerve paths could be accurately mapped preoperatively using the TENS procedure as confirmed by direct visualization of the nerve. This stimulation device is easy to use and offers highly accurate mapping of nerves for surgical planning without major complications. The authors conclude that TENS is a useful tool for noninvasive nerve localization and makes tumor resection a safe and smooth procedure. PMID:26420473

  13. Muscle acellular scaffold as a biomaterial: effects on C2C12 cell differentiation and interaction with the murine host environment

    PubMed Central

    Perniconi, Barbara; Coletti, Dario; Aulino, Paola; Costa, Alessandra; Aprile, Paola; Santacroce, Luigi; Chiaravalloti, Ernesto; Coquelin, Laura; Chevallier, Nathalie; Teodori, Laura; Adamo, Sergio; Marrelli, Massimo; Tatullo, Marco

    2014-01-01

    The extracellular matrix (ECM) of decellularized organs possesses the characteristics of the ideal tissue-engineering scaffold (i.e., histocompatibility, porosity, degradability, non-toxicity). We previously observed that the muscle acellular scaffold (MAS) is a pro-myogenic environment in vivo. In order to determine whether MAS, which is basically muscle ECM, behaves as a myogenic environment, regardless of its location, we analyzed MAS interaction with both muscle and non-muscle cells and tissues, to assess the effects of MAS on cell differentiation. Bone morphogenetic protein treatment of C2C12 cells cultured within MAS induced osteogenic differentiation in vitro, thus suggesting that MAS does not irreversibly commit cells to myogenesis. In vivo MAS supported formation of nascent muscle fibers when replacing a muscle (orthotopic position). However, heterotopically grafted MAS did not give rise to muscle fibers when transplanted within the renal capsule. Also, no muscle formation was observed when MAS was transplanted under the xiphoid process, in spite of the abundant presence of cells migrating along the laminin-based MAS structure. Taken together, our results suggest that MAS itself is not sufficient to induce myogenic differentiation. It is likely that the pro-myogenic environment of MAS is not strictly related to the intrinsic properties of the muscle scaffold (e.g., specific muscle ECM proteins). Indeed, it is more likely that myogenic stem cells colonizing MAS recognize a muscle environment that ultimately allows terminal myogenic differentiation. In conclusion, MAS may represent a suitable environment for muscle and non-muscle 3D constructs characterized by a highly organized structure whose relative stability promotes integration with the surrounding tissues. Our work highlights the plasticity of MAS, suggesting that it may be possible to consider MAS for a wider range of tissue engineering applications than the mere replacement of volumetric muscle loss

  14. Biological conduits combining bone marrow mesenchymal stem cells and extracellular matrix to treat long-segment sciatic nerve defects

    PubMed Central

    Wang, Yang; Li, Zheng-wei; Luo, Min; Li, Ya-jun; Zhang, Ke-qiang

    2015-01-01

    found with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells + extracellular matrix gel grafts than with the polylactic glycolic acid conduit + bone marrow mesenchymal stem cells grafts and the autologous nerve grafts. PMID:26199615

  15. Unusual Origin of a Double Upper Subscapular Nerve from the Suprascapular Nerve and the Posterior Division of the Upper Trunk of the Brachial Plexus: A Case Report

    PubMed Central

    Koutsouflianiotis, Konstantinos; Iliou, Kalliopi; Bitsis, Theodosios; Kitsoulis, Panagiotis

    2016-01-01

    A double upper subscapular nerve on the right side was detected in a male cadaver, with the proximal one arising from the suprascapular nerve and the distal one from the posterior division of the upper trunk of the brachial plexus. Both of them penetrated and supplied the uppermost portion of the right subscapularis muscle. That anatomic variation was associated with a median nerve formed by two lateral roots. The origin and pattern of the upper subscapular nerve displays high variability, however the presented combination of the variable origin of a double upper subscapular nerve has rarely been described in the literature. The knowledge of such an anatomic variation is essential for the surgeon operating in the region especially in instances of brachial plexus’ repair after any traumatic injury. Moreover, the awareness of the precise origin and topography of these nerves is important for the physician attempting to block these nerves or utilizing these nerves as grafts for neurotization of adjacent damaged nerves of the brachial plexus. PMID:27504272

  16. Unusual Origin of a Double Upper Subscapular Nerve from the Suprascapular Nerve and the Posterior Division of the Upper Trunk of the Brachial Plexus: A Case Report.

    PubMed

    Paraskevas, George; Koutsouflianiotis, Konstantinos; Iliou, Kalliopi; Bitsis, Theodosios; Kitsoulis, Panagiotis

    2016-06-01

    A double upper subscapular nerve on the right side was detected in a male cadaver, with the proximal one arising from the suprascapular nerve and the distal one from the posterior division of the upper trunk of the brachial plexus. Both of them penetrated and supplied the uppermost portion of the right subscapularis muscle. That anatomic variation was associated with a median nerve formed by two lateral roots. The origin and pattern of the upper subscapular nerve displays high variability, however the presented combination of the variable origin of a double upper subscapular nerve has rarely been described in the literature. The knowledge of such an anatomic variation is essential for the surgeon operating in the region especially in instances of brachial plexus' repair after any traumatic injury. Moreover, the awareness of the precise origin and topography of these nerves is important for the physician attempting to block these nerves or utilizing these nerves as grafts for neurotization of adjacent damaged nerves of the brachial plexus. PMID:27504272

  17. Dynamic Quantification of Host Schwann Cell Migration into Peripheral Nerve Allografts

    PubMed Central

    Whitlock, Elizabeth L.; Myckatyn, Terence M.; Tong, Alice Y.; Yee, Andrew; Yan, Ying; Magill, Christina K.; Johnson, Philip J.; Mackinnon, Susan E.

    2010-01-01

    Host Schwann cell (SC) migration into nerve allografts is the limiting factor in the duration of immunosuppression following peripheral nerve allotransplantation, and may be affected by different immunosuppressive regimens. Our objective was to compare SC migration patterns between clinical and experimental immunosuppression regimens both over time and at the harvest endpoint. Eighty mice that express GFP under the control of the Schwann cell specific S100 promoter were engrafted with allogeneic, nonfluorescent sciatic nerve grafts. Mice received immunosuppression with either tacrolimus (FK506), or experimental T-cell triple costimulation blockade (CSB), consisting of CTLA4-immunoglobulin fusion protein, anti-CD40 monoclonal antibody, and anti-inducible costimulator monoclonal antibody. Migration of GFP-expressing host SCs into wild-type allografts was assessed in vivo every 3 weeks until 15 weeks postoperatively, and explanted allografts were evaluated for immunohistochemical staining patterns to differentiate graft from host SCs. Immunosuppression with tacrolimus exhibited a plateau of SC migration, characterized by significant early migration (< 3 weeks) followed by a constant level of host SCs in the graft (15 weeks). At the endpoint, graft fluorescence was decreased relative to surrounding host nerve, and donor SCs persisted within the graft. CSB-treated mice displayed gradually increasing migration of host SCs into the graft, without the plateau noted in tacrolimus-treated mice, and also maintained a population of donor SCs at the 15-week endpoint. SC migration patterns are affected by immunosuppressant choice, particularly in the immediate postoperative period, and the use of a single treatment of CSB may allow for gradual population of nerve allografts with host SCs. PMID:20633557

  18. Confocal Laser Scanning Microscopy Evaluation of an Acellular Dermis Tissue Transplant (Epiflex®)

    PubMed Central

    Hohenberger, Peter

    2012-01-01

    The structure of a biological scaffold is a major determinant of its biological characteristics and its interaction with cells. An acellular dermis tissue transplant must undergo a series of processing steps, to remove cells and genetic material and provide the sterility required for surgical use. During manufacturing and sterilization the structure and composition of tissue transplants may change. The composition of the human cell-free dermis transplant Epiflex® was investigated with specific attention paid to its structure, matrix composition, cellular content and biomechanics. We demonstrated that after processing, the structure of Epiflex remains almost unchanged with an intact collagen network and extracellular matrix (ECM) protein composition providing natural cell interactions. Although the ready to use transplant does contain some cellular and DNA debris, the processing procedure results in a total destruction of cells and active DNA which is a requirement for an immunologically inert and biologically safe substrate. Its biomechanical parameters do not change significantly during the processing. PMID:23056225

  19. Gravity related behavior of the acellular slime mold Physarum polycephalum (7-IML-1)

    NASA Technical Reports Server (NTRS)

    Block, I.

    1992-01-01

    The objective of the experiment is to investigate the effect of near weightlessness on a single cell. The test object is the acellular slime mold Physarum polycephalum. This cell is composed of a network of protoplastic strands which perform rhythmic contractions in the minute range. These contractions of the strands' ectoplastic walls generate the force to drive the vigorous shuttle streaming of fluid protoplasm inside the strands (hydrostatic pressure flow). A net transport of protoplasm in one direction determines the direction of the cell's locomotion itself. In this way, gravity modifies the contraction rhythm of the strands, the streaming velocity of protoplasm in the strands, and the direction of locomotion of the whole slime mold (geotaxis). The other parts of this experiment will address the major question of how this cell, which does not possess any specialized gravireceptors, gets the information about the direction of the gravity vector. Details of the experimental setup are given.

  20. Spider Silk Constructs Enhance Axonal Regeneration and Remyelination in Long Nerve Defects in Sheep

    PubMed Central

    Radtke, Christine; Allmeling, Christina; Waldmann, Karl-Heinz; Reimers, Kerstin; Thies, Kerstin; Schenk, Henning C.; Hillmer, Anja; Guggenheim, Merlin; Brandes, Gudrun; Vogt, Peter M.

    2011-01-01

    Background Surgical reapposition of peripheral nerve results in some axonal regeneration and functional recovery, but the clinical outcome in long distance nerve defects is disappointing and research continues to utilize further interventional approaches to optimize functional recovery. We describe the use of nerve constructs consisting of decellularized vein grafts filled with spider silk fibers as a guiding material to bridge a 6.0 cm tibial nerve defect in adult sheep. Methodology/Principal Findings The nerve constructs were compared to autologous nerve grafts. Regeneration was evaluated for clinical, electrophysiological and histological outcome. Electrophysiological recordings were obtained at 6 months and 10 months post surgery in each group. Ten months later, the nerves were removed and prepared for immunostaining, electrophysiological and electron microscopy. Immunostaining for sodium channel (NaV 1.6) was used to define nodes of Ranvier on regenerated axons in combination with anti-S100 and neurofilament. Anti-S100 was used to identify Schwann cells. Axons regenerated through the constructs and were myelinated indicating migration of Schwann cells into the constructs. Nodes of Ranvier between myelin segments were observed and identified by intense sodium channel (NaV 1.6) staining on the regenerated axons. There was no significant difference in electrophysiological results between control autologous experimental and construct implantation indicating that our construct are an effective alternative to autologous nerve transplantation. Conclusions/Significance This study demonstrates that spider silk enhances Schwann cell migration, axonal regrowth and remyelination including electrophysiological recovery in a long-distance peripheral nerve gap model resulting in functional recovery. This improvement in nerve regeneration could have significant clinical implications for reconstructive nerve surgery. PMID:21364921

  1. Radial Nerve Tendon Transfers.

    PubMed

    Cheah, Andre Eu-Jin; Etcheson, Jennifer; Yao, Jeffrey

    2016-08-01

    Radial nerve palsy typically occurs as a result of trauma or iatrogenic injury and leads to the loss of wrist extension, finger extension, thumb extension, and a reduction in grip strength. In the absence of nerve recovery, reconstruction of motor function involves tendon transfer surgery. The most common donor tendons include the pronator teres, wrist flexors, and finger flexors. The type of tendon transfer is classified based on the donor for the extensor digitorum communis. Good outcomes have been reported for most methods of radial nerve tendon transfers as is typical for positional tendon transfers not requiring significant power. PMID:27387076

  2. Physiological distal drift in rat molars contributes to acellular cementum formation.

    PubMed

    Tsuchiya, Shinobu; Tsuchiya, Masahiro; Nishioka, Takashi; Suzuki, Osamu; Sasano, Yasuyuki; Igarashi, Kaoru

    2013-08-01

    Occlusal forces may induce the physiological teeth migration in humans, but there is little direct evidence. Rat molars are known to migrate distally during aging, possibly caused by occlusal forces. The purpose of this study was to determine if a reduction in occlusion would decrease teeth migration and affect associated periodontal structures such as cementum. To reduce occlusal forces, the right upper first molar (M1) in juvenile rats was extracted. The transition of the position of upper second molar (M2) and formation of M2 cementum was followed during aging. From the cephalometric analyses, upper M2 was located more anterior compared with the original position with aging after M1 extraction. Associated with this "slowing-down" of the physiological drift, cementum thickness on distal surface, but not on mesial surface, of M2 root was significantly increased. The accumulation of alizarin red as vital stain indicative of calcification, was observed in the distal cementum of M2 root only on the side of M1 extraction. Extraction of M1 that results in less functional loading, distinctly attenuates the physiological drift only in the upper dentition. The decreased physiological drift appears to activate acellular cementum formation only on distal surface of M2 root, perhaps due to reduced mechanical stress associated with the attenuated distal drift. In conclusion, the physiological distal drift in rat molars appears to be largely driven by the occlusal force and also affects the formation of acellular cementum. These findings provide additional direct evidence for an important role of occlusal forces in tooth migration. PMID:23775928

  3. Is Sterile Better Than Aseptic? Comparing the Microbiology of Acellular Dermal Matrices

    PubMed Central

    Klein, Gabriel M.; Nasser, Ahmed E.; Phillips, Brett T.; Gersch, Robert P.; Fourman, Mitchell S.; Lilo, Sarit E.; Fritz, Jason R.; Khan, Sami U.; Dagum, Alexander B.

    2016-01-01

    Introduction: Postoperative infections are a major complication associated with tissue-expander-based breast reconstruction. The use of acellular dermal matrix (ADM) in this surgery has been identified as a potential reservoir of infection, prompting the development of sterile ADM. Although aseptic and sterile ADMs have been investigated, no study has focused on the occurrence and clinical outcome of bacterial colonization before implantation. Methods: Samples of aseptic AlloDerm, sterile Ready-To-Use AlloDerm, and AlloMax were taken before implantation. These samples were incubated in Tryptic soy broth overnight before being streaked on Trypticase soy agar, MacConkey agar, and 5% blood agar plates for culture and incubated for 48 hours. Culture results were cross-referenced with patient outcomes for 1 year postoperatively. Results: A total of 92 samples of ADM were collected from 63 patients. There were 15 cases of postoperative surgical site infection (16.3%). Only 1 sample of ADM (AlloMax) showed growth of Escherichia coli, which was likely a result of contamination. That patient did not develop any infectious sequelae. Patient outcomes showed no difference in the incidence of seroma or infection between sterile and aseptic ADMs. Conclusions: This study evaluates the microbiology of acellular dermal matrices before use in breast reconstruction. No difference was found in the preoperative bacterial load of either aseptic or sterile ADM. No significant difference was noted in infection or seroma formation. Given these results, we believe aseptic processing used on ADMs is equivalent to sterile processing in our patient cohort in terms of clinical infection and seroma occurrence postoperatively. PMID:27482500

  4. Sonographic Appearance of the Median Nerve Following Revision Carpal Tunnel Surgery

    PubMed Central

    Shapiro, Shane A; Alkhamisi, Ashkan; Pujalte, George G A

    2016-01-01

    The main objective of this pictorial essay is to illustrate the sonographic appearance of the postoperative carpal tunnel and median nerve. Carpal tunnel surgical treatment failures have been shown to occur in up to 19% of a large series requiring re-exploration. Surgical management options for recurrent carpal tunnel syndrome (CTS) include revision release, neurolysis, vein wrapping, and fat grafting procedures. While several descriptions of median nerve entrapment in CTS exist in the ultrasound literature, little is written regarding its postoperative appearance. We report the sonographic changes in the appearance of the median nerve and postoperative carpal tunnel. PMID:27195177

  5. Grafting Technique to Eliminate Rootstock Suckering of Grafted Tomatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  6. Grafts for Ridge Preservation

    PubMed Central

    Jamjoom, Amal; Cohen, Robert E.

    2015-01-01

    Alveolar ridge bone resorption is a biologic phenomenon that occurs following tooth extraction and cannot be prevented. This paper reviews the vertical and horizontal ridge dimensional changes that are associated with tooth extraction. It also provides an overview of the advantages of ridge preservation as well as grafting materials. A Medline search among English language papers was performed in March 2015 using alveolar ridge preservation, ridge augmentation, and various graft types as search terms. Additional papers were considered following the preliminary review of the initial search that were relevant to alveolar ridge preservation. The literature suggests that ridge preservation methods and augmentation techniques are available to minimize and restore available bone. Numerous grafting materials, such as autografts, allografts, xenografts, and alloplasts, currently are used for ridge preservation. Other materials, such as growth factors, also can be used to enhance biologic outcome. PMID:26262646

  7. Alveolar bone grafting

    PubMed Central

    Lilja, Jan

    2009-01-01

    In patients with cleft lip and palate, bone grafting in the mixed dentition in the residual alveolar cleft has become a well-established procedure. The main advantages can be summarised as follows: stabilisation of the maxillary arch; facilitation of eruption of the canine and sometimes facilitation of the lateral incisor eruption; providing bony support to the teeth adjacent to the cleft; raising the alar base of the nose; facilitation of closure of an oro-nasal fistula; making it possible to insert a titanium fixture in the grafted site and to obtain favourable periodontal conditions of the teeth within and adjacent to the cleft. The timing of the ABG surgery take into consideration not only eruption of the canine but also that of the lateral incisor, if present. The best time for bone grafting surgery is when a thin shell of bone still covers the soon erupting lateral incisor or canine tooth close to the cleft. PMID:19884665

  8. Acellularization-Induced Changes in Tensile Properties Are Organ Specific - An In-Vitro Mechanical and Structural Analysis of Porcine Soft Tissues

    PubMed Central

    Aust, Gabriela; Boldt, Andreas; Fritsch, Sebastian; Keil, Isabel; Koch, Holger; Möbius, Robert; Scheidt, Holger A.; Wagner, Martin F. X.; Hammer, Niels

    2016-01-01

    Introduction Though xenogeneic acellular scaffolds are frequently used for surgical reconstruction, knowledge of their mechanical properties is lacking. This study compared the mechanical, histological and ultrastructural properties of various native and acellular specimens. Materials and Methods Porcine esophagi, ureters and skin were tested mechanically in a native or acellular condition, focusing on the elastic modulus, ultimate tensile stress and maximum strain. The testing protocol for soft tissues was standardized, including the adaption of the tissue’s water content and partial plastination to minimize material slippage as well as templates for normed sample dimensions and precise cross-section measurements. The native and acellular tissues were compared at the microscopic and ultrastructural level with a focus on type I collagens. Results Increased elastic modulus and ultimate tensile stress values were quantified in acellular esophagi and ureters compared to the native condition. In contrast, these values were strongly decreased in the skin after acellularization. Acellularization-related decreases in maximum strain were found in all tissues. Type I collagens were well-preserved in these samples; however, clotting and a loss of cross-linking type I collagens was observed ultrastructurally. Elastins and fibronectins were preserved in the esophagi and ureters. A loss of the epidermal layer and decreased fibronectin content was present in the skin. Discussion Acellularization induces changes in the tensile properties of soft tissues. Some of these changes appear to be organ specific. Loss of cross-linking type I collagen may indicate increased mechanical strength due to decreasing transverse forces acting upon the scaffolds, whereas fibronectin loss may be related to decreased load-bearing capacity. Potentially, the alterations in tissue mechanics are linked to organ function and to the interplay of cells and the extracellular matrix, which is different in

  9. Ulnar nerve dysfunction

    MedlinePlus

    ... pressure on the elbow An elbow fracture or dislocation Temporary pain and tingling of this nerve can ... Saunders; 2011:chap 428. Read More Broken bone Dislocation Mononeuritis multiplex Mononeuropathy Myelin Peripheral neuropathy Systemic Update ...

  10. Diabetic Nerve Problems

    MedlinePlus

    ... at the wrong times. This damage is called diabetic neuropathy. Over half of people with diabetes get ... you change positions quickly Your doctor will diagnose diabetic neuropathy with a physical exam and nerve tests. ...

  11. Ulnar nerve dysfunction

    MedlinePlus

    ... surface of the body where it crosses the elbow. The damage destroys the nerve covering ( myelin sheath) ... be caused by: Long-term pressure on the elbow An elbow fracture or dislocation Temporary pain and ...

  12. Degenerative Nerve Diseases

    MedlinePlus

    Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many of these diseases are genetic. Sometimes the cause is a medical ...

  13. Common peroneal nerve dysfunction

    MedlinePlus

    ... people: Who are very thin (for example, from anorexia nervosa ) Who have certain autoimmune conditions, such as ... Elsevier; 2013:chap 22. Read More Alertness - decreased Anorexia Broken bone Diabetes and nerve damage Mononeuritis multiplex ...

  14. Femoral nerve dysfunction

    MedlinePlus

    ... An abnormal knee reflex Smaller than normal quadriceps muscles on the front of the thigh Tests that may be done include: Electromyography ( EMG ) Nerve conduction tests ( NCV ), usually done at ...

  15. Femoral nerve dysfunction

    MedlinePlus

    Neuropathy - femoral nerve; Femoral neuropathy ... Craig EJ, Clinchot DM. Femoral neuropathy. In: Frontera WR, Silver JK, Rizzo TD Jr, eds. Essentials of Physical Medicine and Rehabilitation: Musculoskeletal Disorders, Pain, and Rehabilitation . 3rd ...

  16. Diabetic Nerve Problems

    MedlinePlus

    ... the wrong times. This damage is called diabetic neuropathy. Over half of people with diabetes get it. ... change positions quickly Your doctor will diagnose diabetic neuropathy with a physical exam and nerve tests. Controlling ...

  17. Schwannoma of Extraocular Nerves

    PubMed Central

    Niazi, Wasim; Boggan, James E.

    1994-01-01

    An unusual case of schwannoma arising from the third cranial nerve in a thirteen year old male is reported. The patient presented with paresis of the right oculomotor nerve and ipsilateral hemiparesis. The clinical features of this case are discussed and the pertinent medical literature reviewed. ImagesFigure 1p220-bFigure 2Figure 3Figure 4Figure 5Figure 6 PMID:17171175

  18. Skin grafting of the horse.

    PubMed

    Schumacher, J; Hanselka, D V

    1989-12-01

    Free autogenous skin grafting of the horse is indicated for wounds too large to heal by contraction and epithelization. Techniques of pinch, punch, tunnel, and sheet grafting are described. Allografting and storage of skin for delayed grafting are discussed. PMID:2691033

  19. Bone Grafts in Craniofacial Surgery

    PubMed Central

    Elsalanty, Mohammed E.; Genecov, David G.

    2009-01-01

    Reconstruction of cranial and maxillofacial defects is a challenging task. The standard reconstruction method has been bone grafting. In this review, we shall describe the biological principles of bone graft healing, as pertinent to craniofacial reconstruction. Different types and sources of bone grafts will be discussed, as well as new methods of bone defect reconstruction. PMID:22110806

  20. Dissection of intercostal nerves by means of assisted video thoracoscopy: experimental study

    PubMed Central

    2013-01-01

    In total brachial plexus preganglionic lesions (C5-C6-C7-C8 and T1) different extraplexual neurotizations are indicated for partial motor function restitution. Mostly for the flexion of the elbow. Neurotization with intercostal nerves (ICN) to musculocutaneous nerve has been known and accepted during many years with different results 2 - 5. The customary technique as described by various authors is carried out by means of a large submammary incision to harvest three or four intercostal nerves (Figure 1). Then are connected by direct suture or grafts to the musculocutaneous nerve or its motor branches 6 - 7. In this article the authors described the possibility of dissection intercostal nerves by means of assisted video thoracoscopy. (VATS-videdo assisted thoracic surgery). PMID:23406448

  1. Ultrasound in Dual Nerve Impairment after Proximal Radial Nerve Lesion

    PubMed Central

    Lämmer, Alexandra B; Schwab, Stefan; Schramm, Axel

    2015-01-01

    Introduction Sonography in classical nerve entrapment syndromes is an established and validated method. In contrast, few publications highlight lesions of the radial nerve, particularly of the posterior interosseus nerve (PIN). Method Five patients with a radial nerve lesion were investigated by electromyography, nerve conduction velocity and ultrasound. Further normative values of 26 healthy subjects were evaluated. Results Four patients presented a clinical and electrophysiological proximal axonal radial nerve lesion and one patient showed a typical posterior interosseous nerve syndrome (PINS). The patient with PINS presented an enlargement of the PIN anterior to the supinator muscle. However four patients with proximal lesions showed an unexpected significant enlargement of the PIN within the supinator muscle. Conclusion High-resolution sonography is a feasible method to demonstrate the radial nerve including its distal branches. At least in axonal radial nerve lesions, sonography might reveal abnormalities far distant from a primary proximal lesion site clearly distinct from the appearance in classical PINS. PMID:25992766

  2. Quadratus lumborum block for femoral–femoral bypass graft placement

    PubMed Central

    Watanabe, Kunitaro; Mitsuda, Shingo; Tokumine, Joho; Lefor, Alan Kawarai; Moriyama, Kumi; Yorozu, Tomoko

    2016-01-01

    Abstract Introduction: Atherosclerosis has a complex etiology that leads to arterial obstruction and often results in inadequate perfusion of the distal limbs. Patients with atherosclerosis can have severe complications of this condition, with widespread systemic manifestations, and the operations undertaken are often challenging for anesthesiologists. Case report: A 79-year-old woman with chronic heart failure and respiratory dysfunction presented with bilateral gangrene of the distal lower extremities with obstruction of the left common iliac artery due to atherosclerosis. Femoral–femoral bypass graft and bilateral foot amputations were planned. Spinal anesthesia failed due to severe scoliosis and deformed vertebrae. General anesthesia was induced after performing multiple nerve blocks including quadratus lumborum, sciatic nerve, femoral nerve, lateral femoral cutaneous nerve, and obturator nerve blocks. However, general anesthesia was abandoned because of deterioration in systemic perfusion. The surgery was completed; the patient remained comfortable and awake without the need for further analgesics. Conclusion: Quadratus lumborum block may be a useful anesthetic technique to perform femoral–femoral bypass. PMID:27583851

  3. Grafting for disease resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The primary purpose of grafting vegetables worldwide has been to provide resistance to soil-borne diseases. The potential loss of methyl bromide as a soil fumigant combined with pathogen resistance to commonly used pesticides will make resistance to soil-borne pathogens even more important in the fu...

  4. Acrylonitrile grafted to PVDF

    SciTech Connect

    Yang, Jin; Eitouni, Hany Basam

    2015-03-31

    PVDF-g-PAN has been synthesized by grafting polyacrylonitrile onto polyvinylidene fluoride using an ATRP/AGET method. The novel polymer is ionically conducive and has much more flexibility than PVDF alone, making it especially useful either as a binder in battery cell electrodes or as a polymer electrolyte in a battery cell.

  5. Three-dimensional scaffolds of acellular human and porcine lungs for high throughput studies of lung disease and regeneration

    PubMed Central

    Wagner, Darcy E.; Bonenfant, Nicholas R.; Sokocevic, Dino; DeSarno, Michael; Borg, Zachary; Parsons, Charles; Brooks, Elice M.; Platz, Joseph; Khalpey, Zain; Hoganson, David M.; Deng, Bin; Lam, Ying Wai; Oldinski, Rachael A.; Ashikaga, Takamaru; Weiss, Daniel J.

    2014-01-01

    Acellular scaffolds from complex whole organs such as lung are being increasingly studied for ex vivo organ generation and for in vitro studies of cell-extracellular matrix interactions. We have established effective methods for efficient de- and recellularization of large animal and human lungs including techniques which allow multiple small segments (∼1–3cm3) to be excised that retain 3-dimensional lung structure. Coupled with the use of a synthetic pleural coating, cells can be selectively physiologically inoculated via preserved vascular and airway conduits. Inoculated segments can be further sliced for high throughput studies. Further, we demonstrate thermography as a powerful noninvasive technique for monitoring perfusion decellularization and for evaluating preservation of vascular and airway networks following human and porcine lung decellularization. Collectively, these techniques are a significant step forward as they allow high throughput in vitro studies from a single lung or lobe in a more biologically relevant, three-dimensional acellular scaffold. PMID:24411675

  6. [Biophysics of nerve excitation].

    PubMed

    Kol'e, O R; Maksimov, G V

    2010-01-01

    The studies testifying to the presence of the interrelation between the physiological functions of the organism and physical and chemical processes in nerves are discussed. Changes in some physical and chemical parameters observed both upon elicited rhythmic exaltation of nerves and during the spontaneous rhythmic activity of neurons are analyzed. Upon rhythmic exaltation, a complex of physical and chemical processes is triggered, and reversible structural and metabolic rearrangements at the subcellular and molecular levels occur that do not take place during the generation of a single action potential. Thus, only in conditions of rhythmic exaltation of a nerve, it is possible to reveal those processes that provide exaltation of nerves in the organism. The future possibilities of the investigations combining the biophysical and physiological approaches are substantiated. Characteristic changes in physicochemical parameters are observed in nerves during the generation of a series of action potentials of different frequency and duration ("frequency dependence") under normal physiological conditions, as well as in extreme situations and in nerve pathology. The structural and metabolic rearrangements are directly related to the mode of rhythmic exaltation and proceed both in the course of rhythmic exaltation and after its termination. Participation and the basic components of the nervous fulcrum (an axon, Shwan cell, myelin, subcellular organelles) in the realization of rhythmic exaltation is shown. In the coordination of all processes involved in rhythmic exaltation, the main role is played by the systems of redistribution and transport of intercellular and endocellular calcium. The idea is put forward that myelin of nerve fibers is not only an isolator, but also an "intercellular depot" of calcium and participates in the redistribution of different ions. Thus, the rhythmic excitation is of great importance in the realization of some physiological functions, the

  7. Possible role of dentin matrix in region-specific deposition of cellular and acellular extrinsic fibre cementum.

    PubMed

    Takano, Yoshiro; Sakai, Hideo; Watanabe, Eiko; Ideguchi-Ohma, Noriko; Jayawardena, Chantha K; Arai, Kazumi; Asawa, Yukiyo; Nakano, Yukiko; Shuda, Yoko; Sakamoto, Yujiro; Terashima, Tatsuo

    2003-01-01

    The mechanism whereby a region-specific deposition of the two types of cementum (cellular cementum and acellular extrinsic fibre cementum) is regulated on the growing root surface was tested using bisphosphonate-affected teeth of young rats and guinea pigs. The animals were injected subcutaneously with 8 or 10 mg P x kg body weight(-1) x day(-1) of 1-hydroxyethylidene-1,1-bisphosphonate (HEBP) for 1 or 2 weeks. In rat molars, HEBP prevented mineralization of newly formed root dentin matrix and totally inhibited de novo deposition of acellular extrinsic fibre cementum. Instead, thick cellular cementum was induced on the non-mineralized root dentin surface, irrespective of the position of the root. In both animals, cellular cementum was also induced on the non-mineralized surface of root analogue dentin in HEBP-affected incisors, where only acellular extrinsic fibre cementum is deposited under normal conditions. In normal rat molars, dentin sialoprotein (DSP) was concentrated along the dentin-cellular cementum border, but not that of dentin and acellular extrinsic fibre cementum. In HEBP-affected rat incisors, DSP was shown to penetrate through the non-mineralized dentin into the surrounding tissues, but not through the mineralized portions. These data suggest that, at the site of cellular cementum formation, putative inducing factors for cellular cementum might diffuse into the periodontal space through the newly deposited mantle dentin matrix before it is mineralized. At earlier stages of root formation, mantle dentin might mineralize more promptly not to allow such diffusion. The timing of mineralization of mantle dentin matrix might be the key determinant of the types of the cementum deposited on the growing root surface. PMID:14756246

  8. Peripheral Nerve Regeneration Through Hydrogel-Enriched Chitosan Conduits Containing Engineered Schwann Cells for Drug Delivery.

    PubMed

    Meyer, Cora; Wrobel, Sandra; Raimondo, Stefania; Rochkind, Shimon; Heimann, Claudia; Shahar, Abraham; Ziv-Polat, Ofra; Geuna, Stefano; Grothe, Claudia; Haastert-Talini, Kirsten

    2016-01-01

    Critical length nerve defects in the rat sciatic nerve model were reconstructed with chitosan nerve guides filled with Schwann cells (SCs) containing hydrogel. The transplanted SCs were naive or had been genetically modified to overexpress neurotrophic factors, thus providing a cellular neurotrophic factor delivery system. Prior to the assessment in vivo, in vitro studies evaluating the properties of engineered SCs overexpressing glial cell line-derived neurotrophic factor (GDNF) or fibroblast growth factor 2 (FGF-2(18kDa)) demonstrated their neurite outgrowth inductive bioactivity for sympathetic PC-12 cells as well as for dissociated dorsal root ganglion cell drop cultures. SCs within NVR-hydrogel, which is mainly composed of hyaluronic acid and laminin, were delivered into the lumen of chitosan hollow conduits with a 5% degree of acetylation. The viability and neurotrophic factor production by engineered SCs within NVR-Gel inside the chitosan nerve guides was further demonstrated in vitro. In vivo we studied the outcome of peripheral nerve regeneration after reconstruction of 15-mm nerve gaps with either chitosan/NVR-Gel/SCs composite nerve guides or autologous nerve grafts (ANGs). While ANGs did guarantee for functional sensory and motor regeneration in 100% of the animals, delivery of NVR-Gel into the chitosan nerve guides obviously impaired sufficient axonal outgrowth. This obstacle was overcome to a remarkable extent when the NVR-Gel was enriched with FGF-2(18kDa) overexpressing SCs. PMID:25876520

  9. Hydrogen-rich saline promotes motor functional recovery following peripheral nerve autografting in rats

    PubMed Central

    ZHANG, YONG-GUANG; SHENG, QING-SONG; WANG, ZHI-JUN; LV, LI; ZHAO, WEI; CHEN, JIAN-MEI; XU, HAO

    2015-01-01

    Despite the application of nerve grafts and considerable microsurgical innovations, the functional recovery across a long peripheral nerve gap is generally partial and unsatisfactory. Thus, additional strategies are required to improve nerve regeneration across long nerve gaps. Hydrogen possesses antioxidant and anti-apoptotic properties, which could be neuroprotective in the treatment of peripheral nerve injury; however, such a possibility has not been experimentally tested in vivo. The aim of the present study was to investigate the effectiveness of hydrogen-rich saline in promoting nerve regeneration after 10-mm sciatic nerve autografting in rats. The rats were randomly divided into two groups and intraperitoneally administered a daily regimen of 5 ml/kg hydrogen-rich or normal saline. Axonal regeneration and functional recovery were assessed through a combination of behavioral analyses, electrophysiological evaluations, Fluoro-Gold™ retrograde tracings and histomorphological observations. The data showed that rats receiving hydrogen-rich saline achieved better axonal regeneration and functional recovery than those receiving normal saline. These findings indicated that hydrogen-rich saline promotes nerve regeneration across long gaps, suggesting that hydrogen-rich saline could be used as a neuroprotective agent for peripheral nerve injury therapy. PMID:26622383

  10. Development and Characterization of Acellular Extracellular Matrix Scaffolds from Porcine Menisci for Use in Cartilage Tissue Engineering

    PubMed Central

    Chen, Ying-Chen; Chen, Ray-Neng; Jhan, Hua-Jing; Liu, Der-Zen; Ho, Hsiu-O; Mao, Yong; Kohn, Joachim

    2015-01-01

    Given the growing number of arthritis patients and the limitations of current treatments, there is great urgency to explore cartilage substitutes by tissue engineering. In this study, we developed a novel decellularization method for menisci to prepare acellular extracellular matrix (ECM) scaffolds with minimal adverse effects on the ECM. Among all the acid treatments, formic acid treatment removed most of the cellular contents and preserved the highest ECM contents in the decellularized porcine menisci. Compared with fresh porcine menisci, the content of DNA decreased to 4.10%±0.03%, and there was no significant damage to glycosaminoglycan (GAG) or collagen. Histological staining also confirmed the presence of ECM and the absence of cellularity. In addition, a highly hydrophilic scaffold with three-dimensional interconnected porous structure was fabricated from decellularized menisci tissue. Human chondrocytes showed enhanced cell proliferation and synthesis of chondrocyte ECM including type II collagen and GAG when cultured in this acellular scaffold. Moreover, the scaffold effectively supported chondrogenesis of human bone marrow-derived mesenchymal stem cells. Finally, in vivo implantation was conducted in rats to assess the biocompatibility of the scaffolds. No significant inflammatory response was observed. The acellular ECM scaffold provided a native environment for cells with diverse physiological functions to promote cell proliferation and new tissue formation. This study reported a novel way to prepare decellularized meniscus tissue and demonstrated the potential as scaffolds to support cartilage repair. PMID:25919905

  11. Evaluation of respiratory model employing conventional NIH mice to access the immunity induced by cellular and acellular pertussis vaccines.

    PubMed

    Dias, Alexandre Alves de Souza de Oliveira; Boller, Maria Aparecida Affonso; Werneck, Lúcia Maria Correa; Hirata Junior, Raphael; Mattos-Guaraldi, Ana Luíza

    2006-11-01

    The increasing number of pertussis cases reported on the last twenty years and the existence of new acellular vaccines reinforce the need of research for experimental models to assure the quality of available pertussis vaccines. In this study, allotments of whole-cell and acellular pertussis vaccines were tested through the Intranasal Challenge Model (INM) using conventional NIH mice. The results have been compared to those achieved by the "Gold standard" Intracerebral Challenge Model (ICM). In contrast to ICM, INM results did not show intralaboratorial variations. Statistical analysis by Anova and Ancova tests revealed that the INM presented reproducibility and allowed identification and separation of different products, including three-component and four-component accellular pertussis vaccines. INM revealed differences between pertussis vaccines. INM provides lower distress to the mice allowing the reduction of mice number including the possibility of using conventional mice (less expensive) under non-aseptic environment. Thus, INM may be used as an alternative method of verifying the consistence of allotment production, including acellular pertussis vaccines. PMID:17160282

  12. Development and Characterization of Acellular Extracellular Matrix Scaffolds from Porcine Menisci for Use in Cartilage Tissue Engineering.

    PubMed

    Chen, Ying-Chen; Chen, Ray-Neng; Jhan, Hua-Jing; Liu, Der-Zen; Ho, Hsiu-O; Mao, Yong; Kohn, Joachim; Sheu, Ming-Thau

    2015-09-01

    Given the growing number of arthritis patients and the limitations of current treatments, there is great urgency to explore cartilage substitutes by tissue engineering. In this study, we developed a novel decellularization method for menisci to prepare acellular extracellular matrix (ECM) scaffolds with minimal adverse effects on the ECM. Among all the acid treatments, formic acid treatment removed most of the cellular contents and preserved the highest ECM contents in the decellularized porcine menisci. Compared with fresh porcine menisci, the content of DNA decreased to 4.10%±0.03%, and there was no significant damage to glycosaminoglycan (GAG) or collagen. Histological staining also confirmed the presence of ECM and the absence of cellularity. In addition, a highly hydrophilic scaffold with three-dimensional interconnected porous structure was fabricated from decellularized menisci tissue. Human chondrocytes showed enhanced cell proliferation and synthesis of chondrocyte ECM including type II collagen and GAG when cultured in this acellular scaffold. Moreover, the scaffold effectively supported chondrogenesis of human bone marrow-derived mesenchymal stem cells. Finally, in vivo implantation was conducted in rats to assess the biocompatibility of the scaffolds. No significant inflammatory response was observed. The acellular ECM scaffold provided a native environment for cells with diverse physiological functions to promote cell proliferation and new tissue formation. This study reported a novel way to prepare decellularized meniscus tissue and demonstrated the potential as scaffolds to support cartilage repair. PMID:25919905

  13. Bone grafts and their substitutes.

    PubMed

    Fillingham, Y; Jacobs, J

    2016-01-01

    The continual cycle of bone formation and resorption is carried out by osteoblasts, osteocytes, and osteoclasts under the direction of the bone-signaling pathway. In certain situations the host cycle of bone repair is insufficient and requires the assistance of bone grafts and their substitutes. The fundamental properties of a bone graft are osteoconduction, osteoinduction, osteogenesis, and structural support. Options for bone grafting include autogenous and allograft bone and the various isolated or combined substitutes of calcium sulphate, calcium phosphate, tricalcium phosphate, and coralline hydroxyapatite. Not all bone grafts will have the same properties. As a result, understanding the requirements of the clinical situation and specific properties of the various types of bone grafts is necessary to identify the ideal graft. We present a review of the bone repair process and properties of bone grafts and their substitutes to help guide the clinician in the decision making process. PMID:26733632

  14. Injection nerve palsy

    PubMed Central

    Kakati, Arindhom; Bhat, Dhananjaya; Devi, Bhagavathula Indira; Shukla, Dhaval

    2013-01-01

    Objective: To study the clinical profile and outcome of surgery for injection nerve palsies. Materials and Methods: This is a retrospective study of patients with INP who were treated at our institute during May 2000 to May 2009. Clinical, electroneuromyography (ENMG), and operative findings were noted. Intraoperative nerve action potential monitoring was not used in any case. Outcome of patients who were followed was reviewed. Results: INP comprised 92 (11%) of 837 nerve injury patients. Seventy one patients were children less than 16 years. The nerves involved were sciatic in 80 patients, radial in 8, and others in four. Fifty seven patients had power, grade 0/5. ENMG studies revealed absent compound muscle action potential in 64 and absent sensory nerve action potential in 67 patients. Thirty nine (42.3%) of 92 patients underwent surgery. The mean duration since injury in these patients was 5.2 months (3 months to 11 months). All underwent neurolysis. Only 18 patients who underwent surgery had a follow up of more than 3 months. Ten (55.5%) patients had good or fair outcome after surgery. Except for grade of motor deficit prior to surgery, none of the variables were found to significantly affect the outcome. Conclusion: The outcome of INP is generally good and many patients recover spontaneously. The outcome of surgery is dependent on preoperative motor power. PMID:23546341

  15. Conductive PPY/PDLLA conduit for peripheral nerve regeneration

    PubMed Central

    Xu, Haixing; Holzwarth, Jeremy M.; Yan, Yuhua; Xu, Peihu; Zheng, Hua; Yin, Yixia; Li, Shipu; Ma, Peter X.

    2013-01-01

    The significant drawbacks and lack of success associated with current methods to treat critically sized nerve defects have led to increased interest in neural tissue engineering. Conducting polymers show great promise due to their electrical properties, and in the case of polypyrrole (PPY), its cell compatibility as well. Thus, the goal of this study is to synthesize a conducting composite nerve conduit with PPY and poly(D, L-lactic acid) (PDLLA), assess its ability to support the differentiation of rat pheochromocytoma 12 (PC12) cells in vitro, and determine its ability to promote nerve regeneration in vivo. Different amounts of PPY (5%, 10%, and 15%) are used to synthesize the conduits resulting in different conductivities (5.65, 10.40, and 15.56 ms/cm, respectively). When PC12 cells are seeded on these conduits and stimulated with 100 mV for 2 h, there is a marked increase in both the percentage of neurite-bearing cells and the median neurite length as the content of PPY increased. More importantly, when the PPY/PDLLA nerve conduit was used to repair a rat sciatic nerve defect it performed similarly to the gold standard autologous graft. These promising results illustrate the potential that this PPY/PDLLA conducting composite conduit has for neural tissue engineering. PMID:24138830

  16. Barriers of the peripheral nerve

    PubMed Central

    Peltonen, Sirkku; Alanne, Maria; Peltonen, Juha

    2013-01-01

    This review introduces the traditionally defined anatomic compartments of the peripheral nerves based on light and electron microscopic topography and then explores the cellular and the most recent molecular basis of the different barrier functions operative in peripheral nerves. We also elucidate where, and how, the homeostasis of the normal human peripheral nerve is controlled in situ and how claudin-containing tight junctions contribute to the barriers of peripheral nerve. Also, the human timeline of the development of the barriers of the peripheral nerve is depicted. Finally, potential future therapeutic modalities interfering with the barriers of the peripheral nerve are discussed. PMID:24665400

  17. Morbidity of harvesting of retromolar bone grafts: a prospective study.

    PubMed

    Nkenke, Emeka; Radespiel-Tröger, Martin; Wiltfang, Jörg; Schultze-Mosgau, Stefan; Winkler, Gerhard; Neukam, Friedrich Wilhelm

    2002-10-01

    20 retromolar bone grafts were harvested in outpatients for augmentation of the implant site from January to June 2000 (10 female, 10 male, 40.9 +/- 12.8 years, minimum 17 years, maximum 66 years). The aim of the study was to assess typical complications of this procedure in a prospective manner. For the determination of the superficial sensory function of the inferior alveolar and the lingual nerve, an objective method was used. The bone grafts were harvested for single tooth reconstruction. In 14 cases a ridge augmentation and in 6 cases an endoscopically controlled crestal sinus floor elevation was performed. Preoperatively, the height of bone above the cranial aspect of the inferior alveolar nerve in the retromolar region was assessed radiologically with known markers. The maximum mouth opening was determined. The superficial sensory function of the inferior alveolar and the lingual nerve was assessed with the Pointed-Blunt Test, the Two-Point-Discrimination Test and the objective method of the 'Pain and Thermal Sensitivity' Test (PATH Test). Moreover, the pulp sensitivity of the teeth of the donor site was determined by cold vitality testing. All tests were repeated 1 week postoperatively. Intraoperatively, the width of the retromolar region was measured with a caliper. The patients rated the operative strain on a visual analogue scale. The height of bone above the inferior alveolar nerve in the retromolar region was 11.0 +/- 2.2 mm. The width of the retromolar area was 14.2 +/- 1.9 mm. Postoperatively, the maximal mouth opening changed significantly (40.8 +/- 3.5 mm preoperatively, 38.9 +/- 3.7 mm postoperatively, P = 0.006). However, the reduction was not relevant clinically. A direct injury of the inferior alveolar or lingual nerve did not occur. A sensitivity impairment could not be detected for either of the nerves by the different test methods 1 week postoperatively. The operative strain related to the donor site was significantly less than the strain

  18. Electrophrenic respiration after intercostal to phrenic nerve anastomosis in a patient with anterior spinal artery syndrome: technical case report.

    PubMed

    Krieger, A J; Gropper, M R; Adler, R J

    1994-10-01

    Long-term positive pressure mechanical ventilation has been the standard of care for patients with respiratory insufficiency caused by high cervical spine injury. Stimulation of the phrenic nerves, and thus the diaphragm, with an implanted phrenic nerve pacemaker has provided adequate ventilation and an alternative to the standard. Diaphragmatic pacing, also known as electrophrenic respiration, requires an intact phrenic nerve to act as a conduit for the applied stimulus. Propagation of the stimulus is impossible if the injury sustained has led to axonal loss in the phrenic nerve. This may be expected if the damage to the spinal cord is at the C3-C5 level. If the cell bodies of the motor neurons in this region have been damaged, or direct injury to the phrenic nerve has occurred, then diaphragmatic pacing is not feasible by the traditional method. Microsurgical repair of peripheral nerves and nerve grafting have provided the impetus for research into anastomosis of a viable intercostal nerve to a nonfunctional phrenic nerve, with subsequent reinnervation of the diaphragm. Once successful axonal regeneration and diaphragmatic reinnervation have occurred, the distal phrenic nerve may then be paced. This case documents the first successful institution of electrophrenic respiration after intercostal to phrenic nerve anastomosis. PMID:7808625

  19. NT-3 modulates NPY expression in primary sensory neurons following peripheral nerve injury

    PubMed Central

    STERNE, G. D.; BROWN, R. A.; GREEN, C. J.; TERENGHI, G.

    1998-01-01

    Peripheral nerve transection induces significant changes in neuropeptide expression and content in injured primary sensory neurons, possibly due to loss of target derived neurotrophic support. This study shows that neurotrophin-3 (NT-3) delivery to the injured nerve influences neuropeptide Y (NPY) expression within dorsal root ganglia (DRG) neurons. NT-3 was delivered by grafting impregnated fibronectin (500 ng/ml; NT group) in the axotomised sciatic nerve. Animals grafted with plain fibronectin mats (FN) or nerve grafts (NG) were used as controls. L4 and L5 DRG from operated and contralateral sides were harvested between 5 and 240 d. Using immunohistochemistry and computerised image analysis the percentage, diameter and optical density of neurons expressing calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal peptide (VIP) and NPY were quantified. Sciatic nerve axotomy resulted in significant reduction in expression of CGRP and SP, and significant upregulation of VIP and NPY (P<0.05 for ipsilateral vs contralateral DRG). By d 30, exogenous NT-3 and nerve graft attenuated the upregulation of NPY (P<0.05 for NT and NG vs FN). However, NT-3 administration did not influence the expression of CGRP, SP or VIP. The mean cell diameter of NPY immunoreactive neurons was significantly smaller in the NT-3 group (P<0.05 for NT vs FN and NG) suggesting a differential influence of NT-3 on larger neurons. The optical densities of NPY immunoreactive neurons of equal size were the same in each group at any time point, indicating that the neurons responding to NT-3 downregulate NPY expression to levels not detectable by immunohistochemistry. These results demonstrate that targeted administration of NT-3 regulates the phenotype of a NPY-immunoreactive neuronal subpopulation in the dorsal root ganglia, a further evidence of the trophic role of neurotrophins on primary sensory neurons. PMID:9827642

  20. Fibrolipomatous hamartoma of the inferior calcaneal nerve (Baxter nerve).

    PubMed

    Zeng, Rong; Frederick-Dyer, Katherine; Ferguson, N Lynn; Lewis, James; Fu, Yitong

    2012-09-01

    Fibrolipomatous hamartoma (FLH) is a rare, benign lesion of the peripheral nerves most frequently involving the median nerve and its digital branches (80 %). Pathognomonic MR features of FLH such as coaxial-cable-like appearance on axial planes and a spaghetti-like appearance on coronal planes have been described by Marom and Helms, obviating the need for diagnostic biopsy. We present a case of fibrolipomatous hamartoma of the inferior calcaneal nerve (Baxter nerve) with associated subcutaneous fat proliferation. PMID:22526881

  1. What Are Nerve Blocks for Headache?

    MedlinePlus

    ... nerve blocks for headache? Print Email What are nerve blocks for headache? ACHE Newsletter Sign up for ... entering your e-mail address below. What are nerve blocks for headache? A nerve block is the ...

  2. Siloxane-grafted membranes

    DOEpatents

    Friesen, Dwayne T.; Obligin, Alan S.

    1989-01-01

    Composite cellulosic semipermeable membranes are disclosed which are the covalently bonded reaction product of an asymmetric cellulosic semipermeable membrane and a polysiloxane containing reactive functional groups. The two reactants chemically bond by ether, ester, amide or acrylate linkages to form a siloxane-grafted cellulosic membrane having superior selectivity and flux stability. Selectivity may be enhanced by wetting the surface with a swelling agent such as water.

  3. Siloxane-grafted membranes

    DOEpatents

    Friesen, D.T.; Obligin, A.S.

    1989-10-31

    Composite cellulosic semipermeable membranes are disclosed which are the covalently bonded reaction product of an asymmetric cellulosic semipermeable membrane and a polysiloxane containing reactive functional group. The two reactants chemically bond by ether, ester, amide or acrylate linkages to form a siloxane-grafted cellulosic membrane having superior selectivity and flux stability. Selectivity may be enhanced by wetting the surface with a swelling agent such as water.

  4. Saphenous nerve injury during harvesting of one or two hamstring tendons for anterior cruciate ligament reconstruction☆

    PubMed Central

    de Padua, Vitor Barion Castro; Nascimento, Paulo Emílio Dourado; Silva, Sergio Candido; de Gusmão Canuto, Sergio Marinho; Zuppi, Guilherme Nunes; de Carvalho, Sebastião Marcos Ribeiro

    2015-01-01

    Objective The aim of this study was to assess whether harvesting of two hamstring tendons (semitendinosus and gracilis) has the same rate of nerve injury as harvesting of the semitendinosus tendon alone, used as a triple graft. Methods Changes in sensitivity relating to injury of the infrapatellar branch of the saphenous nerve were evaluated in 110 patients six months after they underwent anterior cruciate ligament (ACL) reconstruction using hamstring tendons. They were divided into two groups: one in which only the semitendinosus was used and the other, the semitendinosus and gracilis. Results The group in which only the semitendinosus was used as a graft presented a nerve injury rate of 36.1%. In the group in which the semitendinosus and gracilis tendons were used, 58.1% of the patients presented altered sensitivity. In the general assessment on all the patients, the nerve injury rate was 50.9%. Conclusion Harvesting the semitendinosus alone and using it in triple form is a viable option for ACL reconstruction and may give rise to fewer nerve injuries relating to branches of the saphenous nerve. PMID:26535201

  5. Overview of currently available Japanese acellular pertussis vaccines and future problems.

    PubMed

    Kamiya, H; Nii, R

    1988-01-01

    Acellular pertussis diphtheria, tetanus vaccine (APDT) was licensed in 1981 in Japan. This vaccine contains pertussis toxin (PT), filamentous hemagglutinin (FHA) and agglutinogen (AGG) as the main protective antigens. The new APDT vaccine produced by each company differs slightly in composition. There are two representative types of vaccine. One vaccine (B type) contains PT and FHA in a ratio of 1 to 1 and the other one (T type) contains PT and FHA in a ratio of 4 to 1 or 9 to 1 and also contains different amounts of AGG. We have been comparing the effectiveness of these two types of vaccine. The adverse reactions of APDT were local reactions such as redness and swelling, with a few febrile cases. No central nervous system adverse reactions were observed. The antibody protective level of this vaccine is also being investigated. After we changed from conventional vaccine to APDT, the frequency of serious adverse reactions was reduced and the number of pertussis infections also gradually decreased. This vaccine should be used for the children world-wide. PMID:3273618

  6. Human keratinocyte growth and differentiation on acellular porcine dermal matrix in relation to wound healing potential.

    PubMed

    Zajicek, Robert; Mandys, Vaclav; Mestak, Ondrej; Sevcik, Jan; Königova, Radana; Matouskova, Eva

    2012-01-01

    A number of implantable biomaterials derived from animal tissues are now used in modern surgery. Xe-Derma is a dry, sterile, acellular porcine dermis. It has a remarkable healing effect on burns and other wounds. Our hypothesis was that the natural biological structure of Xe-Derma plays an important role in keratinocyte proliferation and formation of epidermal architecture in vitro as well as in vivo. The bioactivity of Xe-Derma was studied by a cell culture assay. We analyzed growth and differentiation of human keratinocytes cultured in vitro on Xe-Derma, and we compared the results with formation of neoepidermis in the deep dermal wounds treated with Xe-Derma. Keratinocytes cultured on Xe-Derma submerged in the culture medium achieved confluence in 7-10 days. After lifting the cultures to the air-liquid interface, the keratinocytes were stratified and differentiated within one week, forming an epidermis with basal, spinous, granular, and stratum corneum layers. Immunohistochemical detection of high-molecular weight cytokeratins (HMW CKs), CD29, p63, and involucrin confirmed the similarity of organization and differentiation of the cultured epidermal cells to the normal epidermis. The results suggest that the firm natural structure of Xe-Derma stimulates proliferation and differentiation of human primary keratinocytes and by this way improves wound healing. PMID:22629190

  7. Cellular Response to a Novel Fetal Acellular Collagen Matrix: Implications for Tissue Regeneration

    PubMed Central

    Rennert, Robert C.; Garg, Ravi K.; Gurtner, Geoffrey C.

    2013-01-01

    Introduction. PriMatrix (TEI Biosciences Inc., Boston, MA, USA) is a novel acellular collagen matrix derived from fetal bovine dermis that is designed for use in partial- and full-thickness wounds. This study analyzes the cellular response to PriMatrix in vivo, as well as the ability of this matrix to facilitate normal tissue regeneration. Methods. Five by five mm squares of rehydrated PriMatrix were implanted in a subcutaneous fashion on the dorsum of wild-type mice. Implant site tissue was harvested for histology, immunohistochemistry (IHC), and flow cytometric analyses at multiple time points until day 28. Results. PriMatrix implants were found to go through a biological progression initiated by a transient infiltrate of inflammatory cells, followed by mesenchymal cell recruitment and vascular development. IHC analysis revealed that the majority of the implanted fetal dermal collagen fibers persisted through day 28 but underwent remodeling and cellular repopulation to form tissue with a density and morphology consistent with healthy dermis. Conclusions. PriMatrix implants undergo progressive in vivo remodeling, facilitating the regeneration of histologically normal tissue through a mild inflammatory and progenitor cell response. Regeneration of normal tissue is especially important in a wound environment, and these findings warrant further investigation of PriMatrix in this setting. PMID:23970899

  8. Effect of dynamic seeding methods on the distribution of fibroblasts within human acellular dermis.

    PubMed

    Vitacolonna, Mario; Belharazem, Djeda; Hohenberger, Peter; Roessner, Eric D

    2015-12-01

    The purpose of this investigation was to compare different dynamic cell seeding methods regarding their seeding efficiency, homogeneity, infiltration depth and proliferation within a human acellular dermis. In addition, the growth behaviour was observed during a 12-day static in vitro culture. The dynamic methods included orbital-shaker seeding and the use of a plate centrifuge with different rotational speeds, combinations of low-pressure for matrix degassing and centrifugal seeding. Scaffolds were incubated for up to 12 days statically. Cell distribution and infiltration depth were analysed histologically at days 0, 4, 8 and 12. Seeding efficiency and cell proliferation were quantified with the MTT-assay at the same time points. Centrifugal seeding with 300g for 5 × 1 min combined with matrix degassing significantly increased the seeding efficiency and homogeneity compared to the other methods. However, following static culture, no cells were detectable after 4 days in the inner matrix zones. Furthermore, none of the degassing+centrifugation groups reached a significantly higher proliferation at day 8 compared to the reference. The use of a single dynamic method resulted in an inefficient cell seeding. We archived the highest seeding efficiency, homogeneity and infiltration depth using a combination of degassing+centrifugation at 300g for 5 × 1 min. PMID:25795264

  9. Calcification resistance for photooxidatively crosslinked acellular bovine jugular vein conduits in right-side heart implantation.

    PubMed

    Lü, Wei-Dong; Wang, An-Ping; Wu, Zhong-Shi; Zhang, Ming; Hu, Tie-Hui; Lei, Guang-Yan; Hu, Ye-Rong

    2012-10-01

    This study aimed to investigate the effect of decellularization plus photooxidative crosslinking and ethanol pretreatment on bioprosthetic tissue calcification. Photooxidatively crosslinked acellular (PCA) bovine jugular vein conduits (BJVCs) and their photooxidized controls (n = 5 each) were sterilized in a graded concentration of ethanol solutions for 4 h, and used to reconstruct dog right ventricular outflow tracts. At 1-year implantation, echocardiography showed similar hemodynamic performance, but obvious calcification for the photooxidized BJVC walls. Further histological examination showed intense calcium deposition colocalized with slightly degraded elastic fibers in the photooxidized BJVC walls, with sparsely distributed punctate calcification in the valves and other areas of walls. But PCA BJVCs had apparent degradation of elastic fibers in the walls, with only sparsely distributed punctate calcification in the walls and valves. Content assay demonstrated comparable calcium content for the two groups at preimplantation, whereas less calcium for the PCA group in the walls and similar calcium in the valvular leaflets compared with the photooxidized group at 1-year retrieval. Elastin content assay presented the conduit walls of PCA group had less elastin content at preimplantation, but similar content at 1-year retrieval compared with the photooxidized group. Phospholipid analysis showed phospholipid extraction by ethanol for the PCA group was more efficacious than the photooxidized group. These results indicate that PCA BJVCs resist calcification in right-side heart implantation owing to decellularization, further photooxidative crosslinking, and subsequent phospholipid extraction by ethanol at preimplantation. PMID:22615255

  10. Brainless but Multi-Headed: Decision Making by the Acellular Slime Mould Physarum polycephalum.

    PubMed

    Beekman, Madeleine; Latty, Tanya

    2015-11-20

    Because of its peculiar biology and the ease with which it can be cultured, the acellular slime mould Physarum polycephalum has long been a model organism in a range of disciplines. Due to its macroscopic, syncytial nature, it is no surprise that it has been a favourite amongst cell biologists. Its inclusion in the experimental tool kit of behavioural ecologists is much more recent. These recent studies have certainly paid off. They have shown that, for an organism that lacks a brain or central nervous system, P. polycephalum shows rather complex behaviour. For example, it is capable of finding the shortest path through a maze, it can construct networks as efficient as those designed by humans, it can solve computationally difficult puzzles, it makes multi-objective foraging decisions, it balances its nutrient intake and it even behaves irrationally. Are the slime mould's achievements simply "cute", worthy of mentioning in passing but nothing to take too seriously? Or do they hint at the fundamental processes underlying all decision making? We will address this question after reviewing the decision-making abilities of the slime mould. PMID:26189159

  11. Does Acellular Dermal Matrix Thickness Affect Complication Rate in Tissue Expander Based Breast Reconstruction?

    PubMed Central

    2016-01-01

    Background. While the benefits of using acellular dermal matrices (ADMs) in breast reconstruction are well described, their use has been associated with additional complications. The purpose of this study was to determine if ADM thickness affects complications in breast reconstruction. Methods. A retrospective chart review was performed including all tissue expander based breast reconstructions with AlloDerm (LifeCell, Branchburg, NJ) over 4 years. We evaluated preoperative characteristics and assessed postoperative complications including seroma, hematoma, infection, skin necrosis, and need for reintervention. We reviewed ADM thickness and time to Jackson-Pratt (JP) drain removal. Results. Fifty-five patients underwent 77 ADM-associated tissue expander based breast reconstructions, with average age of 48.1 years and average BMI of 25.9. Average ADM thickness was 1.21 mm. We found higher complication rates in the thick ADM group. Significant associations were found between smokers and skin necrosis (p < 0.0001) and seroma and prolonged JP drainage (p = 0.0004); radiated reconstructed breasts were more likely to suffer infections (p = 0.0085), and elevated BMI is a significant predictor for increased infection rate (p = 0.0037). Conclusion. We found a trend toward increased complication rates with thicker ADMs. In the future, larger prospective studies evaluating thickness may provide more information.

  12. Does Acellular Dermal Matrix Thickness Affect Complication Rate in Tissue Expander Based Breast Reconstruction?

    PubMed

    Rose, Jessica F; Zafar, Sarosh N; Ellsworth Iv, Warren A

    2016-01-01

    Background. While the benefits of using acellular dermal matrices (ADMs) in breast reconstruction are well described, their use has been associated with additional complications. The purpose of this study was to determine if ADM thickness affects complications in breast reconstruction. Methods. A retrospective chart review was performed including all tissue expander based breast reconstructions with AlloDerm (LifeCell, Branchburg, NJ) over 4 years. We evaluated preoperative characteristics and assessed postoperative complications including seroma, hematoma, infection, skin necrosis, and need for reintervention. We reviewed ADM thickness and time to Jackson-Pratt (JP) drain removal. Results. Fifty-five patients underwent 77 ADM-associated tissue expander based breast reconstructions, with average age of 48.1 years and average BMI of 25.9. Average ADM thickness was 1.21 mm. We found higher complication rates in the thick ADM group. Significant associations were found between smokers and skin necrosis (p < 0.0001) and seroma and prolonged JP drainage (p = 0.0004); radiated reconstructed breasts were more likely to suffer infections (p = 0.0085), and elevated BMI is a significant predictor for increased infection rate (p = 0.0037). Conclusion. We found a trend toward increased complication rates with thicker ADMs. In the future, larger prospective studies evaluating thickness may provide more information. PMID:27190645

  13. Acellular Dermal Matrix in Reconstructive Breast Surgery: Survey of Current Practice among Plastic Surgeons

    PubMed Central

    Ibrahim, Ahmed M. S.; Koolen, Pieter G. L.; Ashraf, Azra A.; Kim, Kuylhee; Mureau, Marc A. M.; Lee, Bernard T.

    2015-01-01

    Background: Acellular dermal matrices (ADMs) in plastic surgery have become increasingly popular particularly for breast reconstruction. Despite their advantages, questions exist regarding their association with a possible increased incidence of complications. We describe a collective experience of plastic surgeons’ use of ADMs in reconstructive breast surgery using an internet-based survey. Methods: Members of the American Society of Plastic Surgeons were recruited through voluntary, anonymous participation in an online survey. The web-based survey garnered information about participant demographics and their experience with ADM use in breast reconstruction procedures. After responses were collected, all data were anonymously processed. Results: Data were ascertained through 365 physician responses of which 99% (n = 361) completed the survey. The majority of participants were men (84.5%) between 51 and 60 years (37.4%); 84.2% used ADM in breast reconstruction, including radiated patients (79.7%). ADM use was not favored for nipple reconstruction (81.5%); 94.6% of participants used drains, and 87.8% administered antibiotics postoperatively. The most common complications were seroma (70.9%) and infection (16%), although 57.4% claimed anecdotally that overall complication rate was unchanged after incorporating ADM into their practice. High cost was a deterrent for ADM use (37.5%). Conclusions: Plastic surgeons currently use ADM in breast reconstruction for both immediate and staged procedures. Of those responding, a majority of plastic surgeons will incorporate drains and use postoperative antibiotics for more than 48 hours. PMID:25973359

  14. Preparation and characterization of an advanced collagen aggregate from porcine acellular dermal matrix.

    PubMed

    Liu, Xinhua; Dan, Nianhua; Dan, Weihua

    2016-07-01

    The objective of this study was to extract and characterize an advanced collagen aggregate (Ag-col) from porcine acellular dermal matrix (pADM). Based on histological examination, scanning electron microscopy (SEM) and atomic force microscope (AFM), Ag-col was composed of the D-periodic cross-striated collagen fibrils and thick collagen fiber bundles with uneven diameters and non-orientated arrangement. Fourier transform infrared (FTIR) spectra of pADM, Ag-col and Col were similar and revealed the presence of the triple helix. Circular dichroism (CD) analysis exhibited a slightly higher content of α-helix but inappreciably less amount of random coil structure in Ag-col compared to Col. Moreover, imino acid contents of pADM, Ag-col and Col were 222.43, 218.30 and 190.01 residues/1000 residues, respectively. From zeta potential analysis, a net charge of zero was found at pH 6.45 and 6.11 for Ag-col and Col, respectively. Differential scanning calorimetry (DSC) study suggested that the Td of Ag-col was 20°C higher than that of Col as expected, and dynamic mechanical analysis (DMA) indicated that Ag-col possessed a higher storage modulus but similar loss factor compared to Col. Therefore, the collagen aggregate from pADM could serve as a better alternative source of collagens for further applications in food and biological industries. PMID:27039117

  15. Purification design and practice for pertactin, the third component of acellular pertussis vaccine, from Bordetella pertussis.

    PubMed

    Li, Zenglan; Zhang, Yan; Wang, Qi; Li, Zhengjun; Liu, Yongdong; Zhang, Songping; Zhang, Guifeng; Ma, Guanghui; Luo, Jian; Su, Zhiguo

    2016-07-25

    Development of acellular pertussis vaccine (aPV) requires purification of several components from Bordetella pertussis. While the components pertussis toxin (PT) and filamentous hemagglutinin (FHA) have been successfully purified, the third component, pertactin, proves to be a difficult target due to its very low concentration. In order to solve its purification problem, we performed the surface potential analysis with GRASP2 program. The results demonstrated that there are two major charge patches, one negative and one positive, which are located separately on this linear protein. For this special feature, we designed a dual ion exchange chromatography strategy including an anionic exchange and a cationic exchange process for separation of pertactin from the heat extract of B. pertussis. The initial anionic exchange chromatography concentrated the product from 1.7% to 14.6%, with recovery of 80%. The second cationic exchange chromatography increased the purity to 33%, with recovery of 83%. The final purification was accomplished by hydrophobic interaction chromatography, yielding a purity of 96%. The total recovery of the three columns was 61%. Characterization of the purified antigen was performed with CD, intrinsic fluorescence, HP-SEC and western-blot, showing that the purified protein kept its natural conformation and immune-reactivity. The rationally designed process proved to be feasible, and it is suitable for large-scale preparation of the third aPV component pertactin. PMID:27302339

  16. Complex ventral hernia repair with a human acellular dermal matrix and component separation: A case series

    PubMed Central

    Garcia, Alvaro; Baldoni, Anthony

    2015-01-01

    We present a case series of 19 patients requiring complex abdominal hernia repairs. Patients presented with challenging clinical histories with 95% having multiple significant comorbidities including overweight or obesity (84%), hypertension (53%), diabetes (42%), cancer (26%), and pulmonary disease (16%). The majority of patients (68%) had prior abdominal infections and 53% had at least one failed prior hernia repair. Upon examination, fascial defects averaged 282 cm2. Anterior and posterior component separation was performed with placement of a human acellular dermal mesh. Midline abdominal closure under minimal tension was achieved primarily in all cases. Post-operative complications included 2 adverse events (11%) – one pulmonary embolism and one post-operative hemorrhage requiring transfusion; 6 wound-related complications (32%), 1 seroma (5%) and 1 patient with post-operative ileus (5%). Operative intervention was not required in any of the cases and most patients made an uneventful recovery. Increased patient age and longer OR time were independently predictive of early post-operative complications. At a median 2-year follow-up, three patients had a documented hernia recurrence (16%) and one patient was deceased due to unrelated causes. Conclusion Patients at high risk for post-operative events due to comorbidities, prior abdominal infection and failed mesh repairs do well following component separation reinforced with a human bioprosthetic mesh. Anticipated post-operative complications were managed conservatively and at a median 2-year follow-up, a low rate of hernia recurrence was observed with this approach. PMID:26288732

  17. Tetanus, diphtheria, and acellular pertussis vaccination among women of childbearing age-United States, 2013.

    PubMed

    O'Halloran, Alissa C; Lu, Peng-Jun; Williams, Walter W; Ding, Helen; Meyer, Sarah A

    2016-07-01

    The incidence of pertussis in the United States has increased since the 1990s. Tetanus, diphtheria, and acellular pertussis (Tdap) vaccination of pregnant women provides passive protection to infants. Tdap vaccination is currently recommended for pregnant women during each pregnancy, but coverage among pregnant women and women of childbearing age has been suboptimal. Data from the 2013 Behavioral Risk Factor Surveillance System (BRFSS) and 2013 National Health Interview Survey (NHIS) were used to determine national and state-specific Tdap vaccination coverage among women of childbearing age by self-reported pregnancy status at the time of the survey. Although this study could not assess coverage of Tdap vaccination received during pregnancy because questions on whether Tdap vaccination was received during pregnancy were not asked in BRFSS and NHIS, demographic and access-to-care factors associated with Tdap vaccination coverage in this population were assessed. Tdap vaccination coverage among all women 18-44 years old was 38.4% based on the BRFSS and 23.3% based on the NHIS. Overall, coverage did not differ by pregnancy status at the time of the survey. Coverage among all women 18-44 years old varied widely by state. Age, race and ethnicity, education, number of children in the household, and access-to-care characteristics were independently associated with Tdap vaccination in both surveys. We identified associations of demographic and access-to-care characteristics with Tdap vaccination that can guide strategies to improve vaccination rates in women during pregnancy. PMID:27372388

  18. Optic nerve hypoplasia in children.

    PubMed Central

    Zeki, S. M.; Dutton, G. N.

    1990-01-01

    Optic nerve hypoplasia (ONH) is characterised by a diminished number of optic nerve fibres in the optic nerve(s) and until recently was thought to be rare. It may be associated with a wide range of other congenital abnormalities. Its pathology, clinical features, and the conditions associated with it are reviewed. Neuroendocrine disorders should be actively sought in any infant or child with bilateral ONH. Early recognition of the disorder may in some cases be life saving. Images PMID:2191713

  19. Ischemic Nerve Block.

    ERIC Educational Resources Information Center

    Williams, Ian D.

    This experiment investigated the capability for movement and muscle spindle function at successive stages during the development of ischemic nerve block (INB) by pressure cuff. Two male subjects were observed under six randomly ordered conditions. The duration of index finger oscillation to exhaustion, paced at 1.2Hz., was observed on separate…

  20. Optic Nerve Drusen

    MedlinePlus

    ... the drusen enlarge and the overlying tissue (nerve fiber layer) thins with age, the disc drusen become more apparent. How are optic disc drusen treated? There is no treatment for drusen. In the rare cases (with choroidal neovascularization) laser treatment may be indicated. Revised March 2016 Eye ...

  1. Optic Nerve Atrophy

    MedlinePlus

    ... with the occipital lobe (the part of the brain that interprets vision) like a cable wire. What is optic nerve ... nystagmus. In older patients, peripheral vision and color vision assessment ... around the brain and spinal cord (hydrocephalus) may prevent further optic ...

  2. [Bone grafts in orthopedic surgery].

    PubMed

    Zárate-Kalfópulos, Barón; Reyes-Sánchez, Alejandro

    2006-01-01

    In orthopedic surgery the demand for the use of bone grafts increases daily because of the increasing quantity and complexity of surgical procedures. At present, the gold standard is the autologous bone graft but the failure rate, morbidity of the donor site and limited availability have stimulated a proliferation for finding materials that work as bone graft substitutes. In order to have good success, we must know the different properties of these choices and the environment where the graft is going to be used. As bone graft substitutes and growth factors become clinical realities, a new gold standard will be defined. Tissue engineering and gene therapy techniques have the objective to create an optimum bone graft substitute with a combination of substances with properties of osteconduction, osteogenesis and osteoinduction. PMID:16875525

  3. Distinctive expression of extracellular matrix molecules at mRNA and protein levels during formation of cellular and acellular cementum in the rat.

    PubMed

    Sasano, Y; Maruya, Y; Sato, H; Zhu, J X; Takahashi, I; Mizoguchi, I; Kagayama, M

    2001-02-01

    Little is known about differential expression of extracellular matrices secreted by cementoblasts between cellular and acellular cementum. We hypothesize that cementoblasts lining acellular cementum express extracellular matrix genes differently from those lining cellular cementum, thereby forming two distinct types of extracellular matrices. To test this hypothesis, we investigated spatial and temporal gene expression of selected extracellular matrix molecules, that is type I collagen, bone sialoprotein, osteocalcin and osteopontin, during formation of both cellular and acellular cementum using in situ hybridization. In addition, their extracellularly deposited and accumulated proteins were examined immunohistochemically. The mRNA transcripts of pro-alpha1 (I) collagen were primarily localized in cementoblasts of cellular cementum and cementocytes, while those of bone sialoprotein were predominantly seen in cementoblasts lining acellular cementum. In contrast, osteocalcin was expressed by both types of cementoblasts and cementocytes and so was osteopontin but only transiently. Our immunohistochemical examination revealed that translated proteins were localized extracellularly where the genes had been expressed intracellularly. The present study demonstrated the distinctive expression of genes and proteins of the extracellular matrix molecules between cellular and acellular cementum. PMID:11432645

  4. In vivo study of novel nanofibrous intra-luminal guidance channels to promote nerve regeneration

    NASA Astrophysics Data System (ADS)

    Koh, H. S.; Yong, T.; Teo, W. E.; Chan, C. K.; Puhaindran, M. E.; Tan, T. C.; Lim, A.; Lim, B. H.; Ramakrishna, S.

    2010-08-01

    A novel nanofibrous construct for promoting peripheral nerve repair was fabricated and tested in a rat sciatic nerve defect model. The conduit is made out of bilayered nanofibrous membranes with the nanofibers longitudinally aligned in the lumen and randomly oriented on the outer surface. The intra-luminal guidance channel is made out of aligned nanofibrous yarns. In addition, biomolecules such as laminin and nerve growth factor were incorporated in the nanofibrous nerve construct to determine their efficacy in in vivo nerve regeneration. Muscle reinnervation, withdrawal reflex latency, histological, axon density and electrophysiology tests were carried out to compare the efficacy of nanofibrous constructs with an autograft. Our study showed mixed results when comparing the artificial constructs with an autograft. In some cases, the nanofibrous conduit with aligned nanofibrous yarn as an intra-luminal guidance channel performs better than the autograft in muscle reinnervation and withdrawal reflex latency tests. However, the axon density count is highest in the autograft at mid-graft. Functional recovery was improved with the use of the nerve construct which suggested that this nerve implant has the potential for clinical usage in reconstructing peripheral nerve defects.

  5. Nanostructured Guidance for Peripheral Nerve Injuries: A Review with a Perspective in the Oral and Maxillofacial Area

    PubMed Central

    Sivolella, Stefano; Brunello, Giulia; Ferrarese, Nadia; Puppa, Alessandro Della; D’Avella, Domenico; Bressan, Eriberto; Zavan, Barbara

    2014-01-01

    Injury to peripheral nerves can occur as a result of various surgical procedures, including oral and maxillofacial surgery. In the case of nerve transaction, the gold standard treatment is the end-to-end reconnection of the two nerve stumps. When it cannot be performed, the actual strategies consist of the positioning of a nerve graft between the two stumps. Guided nerve regeneration using nano-structured scaffolds is a promising strategy to promote axon regeneration. Biodegradable electrospun conduits composed of aligned nanofibers is a new class of devices used to improve neurite extension and axon outgrowth. Self assembled peptide nanofibrous scaffolds (SAPNSs) demonstrated promising results in animal models for central nervous system injuries, and, more recently, for peripheral nerve injury. Aims of this work are (1) to review electrospun and self-assembled nanofibrous scaffolds use in vitro and in vivo for peripheral nerve regeneration; and (2) its application in peripheral nerve injuries treatment. The review focused on nanofibrous scaffolds with a diameter of less than approximately 250 nm. The conjugation in a nano scale of a natural bioactive factor with a resorbable synthetic or natural material may represent the best compromise providing both biological and mechanical cues for guided nerve regeneration. Injured peripheral nerves, such as trigeminal and facial, may benefit from these treatments. PMID:24562333

  6. Antimicrobial Graft Copolymer Gels.

    PubMed

    Harvey, Amanda C; Madsen, Jeppe; Douglas, C W Ian; MacNeil, Sheila; Armes, Steven P

    2016-08-01

    In view of the growing worldwide rise in microbial resistance, there is considerable interest in designing new antimicrobial copolymers. The aim of the current study was to investigate the relationship between antimicrobial activity and copolymer composition/architecture to gain a better understanding of their mechanism of action. Specifically, the antibacterial activity of several copolymers based on 2-(methacryloyloxy)ethyl phosphorylcholine [MPC] and 2-hydroxypropyl methacrylate (HPMA) toward Staphylococcus aureus was examined. Both block and graft copolymers were synthesized using either atom transfer radical polymerization or reversible addition-fragmentation chain transfer polymerization and characterized via (1)H NMR, gel permeation chromatography, rheology, and surface tensiometry. Antimicrobial activity was assessed using a range of well-known assays, including direct contact, live/dead staining, and the release of lactate dehydrogenase (LDH), while transmission electron microscopy was used to study the morphology of the bacteria before and after the addition of various copolymers. As expected, PMPC homopolymer was biocompatible but possessed no discernible antimicrobial activity. PMPC-based graft copolymers comprising PHPMA side chains (i.e. PMPC-g-PHPMA) significantly reduced both bacterial growth and viability. In contrast, a PMPC-PHPMA diblock copolymer comprising a PMPC stabilizer block and a hydrophobic core-forming PHPMA block did not exhibit any antimicrobial activity, although it did form a biocompatible worm gel. Surface tensiometry studies and LDH release assays suggest that the PMPC-g-PHPMA graft copolymer exhibits surfactant-like activity. Thus, the observed antimicrobial activity is likely to be the result of the weakly hydrophobic PHPMA chains penetrating (and hence rupturing) the bacterial membrane. PMID:27409712

  7. Serious axillary nerve injury caused by subscapular artery compression resulting from use of backpacks.

    PubMed

    Haninec, Pavel; Mencl, Libor; Bačinský, Peter; Kaiser, Radek

    2013-12-01

    A palsy of the brachial plexus elements caused by carrying a heavy backpack is a very rare injury usually occurring in soldiers or hikers, and recovery is usually spontaneous. We describe here the case of male civilian presenting with an isolated serious axillary nerve palsy associated with chronic backpack use. During the surgery, a dumbbell-shaped neuroma-in-continuity was found which was caused by direct pressure from the subscapular artery. After resection of the neuroma, a nerve graft from the sural nerve was used to reconstruct the nerve. Reinnervation was successful and the patient was able to abduct his arm to its full range, with full muscle strength, within 24 months. PMID:23696291

  8. Nanoparticles carrying neurotrophin-3-modified Schwann cells promote repair of sciatic nerve defects

    PubMed Central

    Zong, Haibin; Zhao, Hongxing; Zhao, Yilei; Jia, Jingling; Yang, Libin; Ma, Chao; Zhang, Yang; Dong, Yuzhen

    2013-01-01

    Schwann cells and neurotrophin-3 play an important role in neural regeneration, but the secretion of neurotrophin-3 from Schwann cells is limited, and exogenous neurotrophin-3 is inactived easily in vivo. In this study, we have transfected neurotrophin-3 into Schwann cells cultured in vitro using nanoparticle liposomes. Results showed that neurotrophin-3 was successfully transfected into Schwann cells, where it was expressed effectively and steadily. A composite of Schwann cells transfected with neurotrophin-3 and poly(lactic-co-glycolic acid) biodegradable conduits was transplanted into rats to repair 10-mm sciatic nerve defects. Transplantation of the composite scaffold could restore the myoelectricity and wave amplitude of the sciatic nerve by electrophysiological examination, promote nerve axonal and myelin regeneration, and delay apoptosis of spinal motor neurons. Experimental findings indicate that neurotrophin-3 transfected Schwann cells combined with bridge grafting can promote neural regeneration and functional recovery after nerve injury. PMID:25206420

  9. Grafting techniques for Peyronie's disease.

    PubMed

    Hatzichristodoulou, Georgios

    2016-06-01

    Peyronie's disease (PD) is a benign fibrotic condition of the penile tunica albuginea. PD can be associated with penile pain, curvature, shortening, and erectile dysfunction (ED). The predominant and most bothersome symptom in affected patients is penile curvature, which can lead to inability to have sexual intercourse. In such cases, surgical correction of the curvature may be required. Plication techniques to correct curvature can cause penile shortening and therefore are generally reserved for curvatures <60°. Penile prosthesis implantation with simultaneous correction of curvature by various means is recommended in PD patients with ED not responding to medical therapy. Grafting techniques are the preferred surgical treatment in patients with penile curvatures >60°, short penis, or hourglass deformity. Patients scheduled for grafting surgery are required to have satisfactory erectile rigidity preoperatively. There are various grafting materials that can be used for closure of the tunica albuginea defect following plaque incision/excision. Both autologous and non-autologous grafts have been used for PD reconstructive surgery, and each graft has its advantages and disadvantages. Novel grafting materials are presented and discussed in this review. A major advantage of the available "off-the-shelf" grafts is that there is no harvesting from a donor site and, thus, morbidity is reduced, and operative times are minimized. Further investigations in regard to tissue-engineered grafts to improve surgical handling and postoperative outcomes are ongoing. Surgeon experience, careful patient selection, patient preference and type of penile deformity affect the choice of graft. This review summarizes the literature within the past 5 years regarding grafting techniques in PD. Surgical outcomes and limitations of grafting techniques are reported. A major objective of this review is dedicated to preoperative considerations and indications for grafting procedures, with the aim

  10. Anesthetic management of post-burn contracture chest with microstomia: Regional nerve blocks to aid in intubation

    PubMed Central

    Subramanyam, Kalavala Lakshminarayana

    2015-01-01

    This case report exemplifies the anesthetic technique of blocking bilateral infraorbital and mental nerves for release of contractures of mouth. A 30 year old female patient of post-acid burn contractures of chest wall and mouth was scheduled for contracture release and skin grafting. Airway assessment revealed severe restriction of mouth opening with limited restriction of neck movements. Contracture release of mouth conducted by blocking bilateral infraorbital and mental nerves, which facilitated intubation easily. This case report highlights the practical advantage of nerve blocks for release of contracture mouth, in case of anticipated difficult airway, over other conventional methods. PMID:25948913

  11. New Chemically Functionalized Nanomaterials for Electrical Nerve Agents Sensors

    NASA Astrophysics Data System (ADS)

    Simonato, Jean-Pierre; Clavaguera, Simon; Carella, Alexandre; Delalande, Michael; Raoul, Nicolas; Lenfant, Stephane; Vuillaume, Dominique; Dubois, Emmanuel

    2011-08-01

    A chemical receptor specific to traces of organophosphorus nerve agents (OPs) has been synthesized and grafted to carbon nanotubes and silicon nanowires in order to make electrical sensors. Our results show that it is possible to detect efficiently sub-ppm traces of OPs with excellent selectivity notably with the use of silicon nanowires by monitoring the Drain-Source current of the SiNW-FET at an optimum back Gate voltage as a function of time. First developments of a prototype have also been realized.

  12. Applications of skin grafting in large animals.

    PubMed

    Wilson, D G

    1990-09-01

    Injuries involving full-thickness skin wounds are common in large animals. Skin grafting can shorten the healing time and improve the cosmetic result. Techniques that have been used successfully in the management of full-thickness skin wounds include full-thickness skin grafts, split-thickness skin grafts, tunnel grafts, pinch/punch grafts, and immediate split-thickness skin grafts. The technical aspects of each of these procedures are detailed and representative cases are presented. PMID:2134606

  13. Grafting Genetically Modified Cells to the Damaged Brain: Restorative Effects of NGF Expression

    NASA Astrophysics Data System (ADS)

    Rosenberg, Michael B.; Friedmann, Theodore; Robertson, Robin C.; Tuszynski, Mark; Wolff, Jon A.; Breakefield, Xandra O.; Gage, Fred H.

    1988-12-01

    Fibroblasts were genetically modified to secrete nerve growth factor (NGF) by infection with a retroviral vector and then implanted into the brains of rats that had surgical lesions of the fimbria-fornix. The grafted cells survived and produced sufficient NGF to prevent the degeneration of cholinergic neurons that would die without treatment. In addition, the protected cholinergic cells sprouted axons that projected in the direction of the cellular source of NGF. These results indicate that a combination of gene transfer and intracerebral grafting may provide an effective treatment for some disorders of the central nervous system.

  14. Ultrasound of Peripheral Nerves

    PubMed Central

    Suk, Jung Im; Walker, Francis O.; Cartwright, Michael S.

    2013-01-01

    Over the last decade, neuromuscular ultrasound has emerged as a useful tool for the diagnosis of peripheral nerve disorders. This article reviews sonographic findings of normal nerves including key quantitative ultrasound measurements that are helpful in the evaluation of focal and possibly generalized peripheral neuropathies. It also discusses several recent papers outlining the evidence base for the use of this technology, as well as new findings in compressive, traumatic, and generalized neuropathies. Ultrasound is well suited for use in electrodiagnostic laboratories where physicians, experienced in both the clinical evaluation of patients and the application of hands-on technology, can integrate findings from the patient’s history, physical examination, electrophysiological studies, and imaging for diagnosis and management. PMID:23314937

  15. Direct Hospital Cost of Outcome Pathways in Implant-Based Reconstruction with Acellular Dermal Matrices

    PubMed Central

    Qureshi, Ali A.; Broderick, Kristen; Funk, Susan; Reaven, Nancy; Tenenbaum, Marissa M.

    2016-01-01

    Background: Current cost data on tissue expansion followed by exchange for permanent implant (TE/I) reconstruction lack a necessary assessment of the experience of a heterogenous breast cancer patient population and their multiple outcome pathways. We extend our previous analysis to that of direct hospital cost as bundling of payments is likely to follow the changing centralization of cancer care at the hospital level. Methods: We performed a retrospective analysis (2003–2009) of TE/I reconstructions with or without an acellular dermal matrix (ADM), namely Alloderm RTM. Postreconstructive events were analyzed and organized into outcome pathways as previously described. Aggregated and normalized inpatient and outpatient hospital direct costs and physician reimbursement were generated for each outcome pathway with or without ADM. Results: Three hundred sixty-seven patients were analyzed. The average 2-year hospital direct cost per TE/I breast reconstruction patient was $11,862 in the +ADM and $12,319 in the −ADM groups (P > 0.05). Initial reconstructions were costlier in the +ADM ($6,868) than in the −ADM ($5,615) group, but the average cost of subsequent postreconstructive events within 2 years was significantly lower in +ADM ($5,176) than −ADM ($6,704) patients (P < 0.05). When a complication occurred, but reconstruction was still completed within 2 years, greater costs were incurred in the −ADM than in the +ADM group for most scenarios, leading to a net equalization of cost between study groups. Conclusion: Although direct hospital cost is an important factor for resource and fund allocation, it should not remain the sole factor when deciding to use ADM in TE/I reconstruction.

  16. On fragmenting, densely mineralised acellular protrusions into articular cartilage and their possible role in osteoarthritis.

    PubMed

    Boyde, A; Davis, G R; Mills, D; Zikmund, T; Cox, T M; Adams, V L; Niker, A; Wilson, P J; Dillon, J P; Ranganath, L R; Jeffery, N; Jarvis, J C; Gallagher, J A

    2014-10-01

    High density mineralised protrusions (HDMP) from the tidemark mineralising front into hyaline articular cartilage (HAC) were first described in Thoroughbred racehorse fetlock joints and later in Icelandic horse hock joints. We now report them in human material. Whole femoral heads removed at operation for joint replacement or from dissection room cadavers were imaged using magnetic resonance imaging (MRI) dual echo steady state at 0.23 mm resolution, then 26-μm resolution high contrast X-ray microtomography, sectioned and embedded in polymethylmethacrylate, blocks cut and polished and re-imaged with 6-μm resolution X-ray microtomography. Tissue mineralisation density was imaged using backscattered electron SEM (BSE SEM) at 20 kV with uncoated samples. HAC histology was studied by BSE SEM after staining block faces with ammonium triiodide solution. HDMP arise via the extrusion of an unknown mineralisable matrix into clefts in HAC, a process of acellular dystrophic calcification. Their formation may be an extension of a crack self-healing mechanism found in bone and articular calcified cartilage. Mineral concentration exceeds that of articular calcified cartilage and is not uniform. It is probable that they have not been reported previously because they are removed by decalcification with standard protocols. Mineral phase morphology frequently shows the agglomeration of many fine particles into larger concretions. HDMP are surrounded by HAC, are brittle, and show fault lines within them. Dense fragments found within damaged HAC could make a significant contribution to joint destruction. At least larger HDMP can be detected with the best MRI imaging ex vivo. PMID:25132002

  17. A Complication Analysis of 2 Acellular Dermal Matrices in Prosthetic-based Breast Reconstruction

    PubMed Central

    Page, Eugenia K.; Hart, Alexandra; Rudderman, Randall; Carlson, Grant W.; Losken, Albert

    2016-01-01

    Background: Acellular dermal matrices (ADM) are now routine in postmastectomy prosthetic-based breast reconstruction. The goal of the current study was to compare the complications of 2 ADM products—AlloDerm and Cortiva. Methods: A retrospective analysis of prosthetic-based breast reconstruction in Atlanta, Ga., over 5 years. Inclusion criteria were the use of the ADM types (AlloDerm or Cortiva) and use of a tissue expander or implant. Statistical analysis compared group demographics, risk factors, and early complications. Results: Of the 298 breast reconstructions, 174 (58.4%) used AlloDerm and 124 (41.6%) used Cortiva. There was no difference in overall complication frequency (16 AlloDerm and 18 Cortiva; P = 0.195). Within specific categories, there was a difference in mastectomy skin flap necrosis, but, based on further regression analysis, this was attributable to differences in body mass index (P = 0.036). Furthermore, there were no differences in the rates of infection (6 AlloDerm and 5 Cortiva; P = 1.0), seroma/hematoma (9 AlloDerm and 7 Cortiva; P = 1.0), or drain duration (13.2 day AlloDerm and 14.2 day Cortiva, P = 0.2). By using a general estimating equation for binomial logistical regression, it was found that only current tobacco use (P = 0.033) was a significant predictor for a complication. Trending predictors were body mass index (P = 0.074) and age (P = 0.093). The type of matrix was not a significant predictor for any of the recorded complication (P = 0.160). Conclusions: Although AlloDerm is well established, we have shown that Cortiva has an equivalent complication frequency. Future work will focus on long-term outcome measures and histological evaluation of vascularization and integration. PMID:27536479

  18. Incidence of Seromas and Infections Using Fenestrated versus Nonfenestrated Acellular Dermal Matrix in Breast Reconstructions

    PubMed Central

    Palaia, David A.; Arthur, Karen S.; Cahan, Anthony C.

    2015-01-01

    Background: Acellular dermal matrices (ADMs) provide clinical benefits in breast reconstruction but have been associated with increased postoperative complications, most frequently seromas. Fenestration of the ADM before insertion into the reconstructed breast may reduce the incidence of postoperative complications. In this retrospective analysis, postoperative complications were assessed after breast reconstruction with or without fenestrated ADMs. Methods: Patients who underwent immediate 2-staged implant breast reconstructions using ADM at a single center were assessed. The number of reconstructed breasts was stratified by ADM fenestration status and ADM type. The incidence of seroma, infection, extrusion, and explantation, and cosmetic score, was compared within the 2 stratified groups. A multivariable regression was performed to identify independent risk factors associated with these complications and aesthetic outcome. Results: In total, data from 450 patients who had 603 breast reconstructions using either AlloDerm or FlexHD demonstrated a significantly higher incidence of seroma with nonfenestrated ADMs (20%) versus fenestrated ADMs (11%; P = 0.0098). Rates of infection and explantation, and cosmetic score, were not influenced by fenestration status. In the multivariable analysis, ADM fenestration remained a significant protective factor for seroma formation. FlexHD also yielded a lower incidence of extrusion (P = 0.0031) and a higher cosmetic score (P = 0.0466) compared with AlloDerm after adjusting for other risk factors. Conclusions: The results of this study support ADM fenestration for reduction of seroma incidence in breast reconstruction, without affecting cosmetic results. Additionally, the choice of ADM may reduce extrusion incidence and improve aesthetic outcomes. PMID:26893994

  19. Plastic Surgery and Acellular Dermal Matrix: Highlighting Trends from 1999 to 2013

    PubMed Central

    Daar, David A; Gandy, Jessica R; Clark, Emily G; Mowlds, Donald S; Paydar, Keyianoosh Z; Wirth, Garrett A

    2016-01-01

    The last decade has ushered in a rapidly expanding global discussion regarding acellular dermal matrix (ADM) applications, economic analyses, technical considerations, benefits, and risks, with recent emphasis on ADM use in breast surgery. This study aims to evaluate global trends in ADM research using bibliometric analysis. The top nine Plastic Surgery journals were determined by impact factor (IF). Each issue of the nine journals between 1999 and 2013 was accessed to compile a database of articles discussing ADM. Publications were further classified by IF, authors’ geographic location, study design, and level of evidence (LOE, I-V). Productivity index and productivity share were calculated for each region. In total, 256 ADM articles were accessed. The annual global publication volume increased significantly by 4.2 (0.87) articles per year (p<0.001), with a mean productivity index of 36.3 (59.0). The mean impact factor of the nine journals increased significantly from 0.61 (0.11) to 2.47 (0.99) from 1993 to 2013 (p<0.001). Despite this increase in the global ADM literature, the majority of research was of weaker LOE (level I: 2.29% and level II: 9.17%). USA contributed the most research (87%), followed by Asia (4.76%) and Western Europe (4.71%). USA contributed the greatest volume of research. Regarding clinical application of ADM, the majority of publications focused on ADM use in breast surgery, specifically breast reconstruction (154 articles, 60.2%). The majority of research was of lower LOE; thus, efforts should be made to strengthen the body of literature, particularly with regard to cost analysis. PMID:27579264

  20. Histologic, Molecular, and Clinical Evaluation of Explanted Breast Prostheses, Capsules, and Acellular Dermal Matrices for Bacteria

    PubMed Central

    Poppler, Louis; Cohen, Justin; Dolen, Utku Can; Schriefer, Andrew E.; Tenenbaum, Marissa M.; Deeken, Corey; Chole, Richard A.; Myckatyn, Terence M.

    2015-01-01

    Background Subclinical infections, manifest as biofilms, are considered an important cause of capsular contracture. Acellular dermal matrices (ADMs) are frequently used in revision surgery to prevent recurrent capsular contractures. Objective We sought to identify an association between capsular contracture and biofilm formation on breast prostheses, capsules, and ADMs in a tissue expander/implant (TE/I) exchange clinical paradigm. Methods Biopsies of the prosthesis, capsule, and ADM from patients (N = 26) undergoing TE/I exchange for permanent breast implant were evaluated for subclinical infection. Capsular contracture was quantified with Baker Grade and intramammary pressure. Biofilm formation was evaluated with specialized cultures, rtPCR, bacterial taxonomy, live:dead staining, and scanning electron microscopy (SEM). Collagen distribution, capsular histology, and ADM remodeling were quantified following fluorescent and light microscopy. Results Prosthetic devices were implanted from 91 to 1115 days. Intramammary pressure increased with Baker Grade. Of 26 patients evaluated, one patient had a positive culture and one patient demonstrated convincing evidence of biofilm morphology on SEM. Following PCR amplification 5 samples randomly selected for 16S rRNA gene sequencing demonstrated an abundance of suborder Micrococcineae, consistent with contamination. Conclusions Our data suggest that bacterial biofilms likely contribute to a proportion, but not all diagnosed capsular contractures. Biofilm formation does not appear to differ significantly between ADMs or capsules. While capsular contracture remains an incompletely understood but common problem in breast implant surgery, advances in imaging, diagnostic, and molecular techniques can now provide more sophisticated insights into the pathophysiology of capsular contracture. Level of Evidence PMID:26229126

  1. Chondrogenesis of Human Infrapatellar Fat Pad Stem Cells on Acellular Dermal Matrix

    PubMed Central

    Ye, Ken; Traianedes, Kathy; Choong, Peter F. M.; Myers, Damian E.

    2016-01-01

    Acellular dermal matrix (ADM) has been in clinical use for decades in numerous surgical applications. The ability for ADM to promote cellular repopulation, revascularisation and tissue regeneration is well documented. Adipose stem cells have the ability to differentiate into mesenchymal tissue types, including bone and cartilage. The aim of this study was to investigate the potential interaction between ADM and adipose stem cells in vitro using TGFβ3 and BMP6. Human infrapatellar fat pad-derived adipose stem cells (IPFP-ASC) were cultured with ADM derived from rat dermis in chondrogenic (TGFβ3 and BMP6) medium in vitro for 2 and 4 weeks. Histology, qPCR, and immunohistochemistry were performed to assess for markers of chondrogenesis (collagen Type II, SOX9 and proteoglycans). At 4 weeks, cell-scaffold constructs displayed cellular changes consistent with chondrogenesis, with evidence of stratification of cell layers and development of a hyaline-like cartilage layer superficially, which stained positively for collagen Type II and proteoglycans. Significant cell–matrix interaction was seen between the cartilage layer and the ADM itself with seamless integration between each layer. Real time qPCR showed significantly increased COL2A1, SOX9, and ACAN gene expression over 4 weeks when compared to control. COL1A2 gene expression remained unchanged over 4 weeks. We believe that the principles that make ADM versatile and successful for tissue regeneration are applicable to cartilage regeneration. This study demonstrates in vitro the ability for IPFP-ASCs to undergo chondrogenesis, infiltrate, and interact with ADM. These outcomes serve as a platform for in vivo modelling of ADM for cartilage repair. PMID:26858950

  2. A New Approach to Minimize Acellular Dermal Matrix Use in Prosthesis-based Breast Reconstruction

    PubMed Central

    Hadad, Ivan; Liu, Allen S.

    2015-01-01

    Background: Acellular dermal matrices (ADMs) are often used to improve lower-pole contour, as well as allow for single-stage reconstruction, but numerous studies have shown an increased complication rate using ADM. As such, our group has developed a minimal-ADM-use technique to lower complications while effectively recreating lower-pole contour. Methods: A total of 380 postmastectomy prosthesis-based breast reconstructions were performed in 265 patients by a single surgeon. One hundred eight reconstructions were performed using the traditional ADM technique, with a large piece of ADM along the entire inferior and lateral borders. Two hundred twenty-five reconstructions were performed with the minimal-use technique, patching only the lateral area of the reconstruction. Thirty-five reconstructions were performed without the use of any ADM for high-risk reconstructions, most often in morbidly obese patients. Results: Comparing the traditional technique with the minimal-use technique, the seroma rate dropped from 3% to 0%. The rate of infection and reconstruction loss fell from 9% to 1%. Upon greatly reducing or eliminating the use of ADM use in obese patients, the seroma rate decreased from 15.4% to 5.7%, and the reconstruction loss rate decreased from 38% to 9%. Conclusions: This article describes a new surgical approach to minimize the amount of ADM necessary to create an aesthetically pleasing breast reconstruction. We believe that this approach helps avoid the complications of seroma, infection, and loss of the reconstruction. In certain obese patients, total avoidance of ADM may be the better choice. PMID:26301161

  3. Potential sites for the perception of gravity in the acellular slime mold Physarum polycephalum

    NASA Astrophysics Data System (ADS)

    Block, I.; Briegleb, W.

    Recently a gravisensitivity of the acellular slime mold Physarum polycephalum, which possesses no specialized gravireceptor, could be established by conducting experiments under simulated and under real near weightlessness. In these experiments macroplasmodia showed a modulation of their contraction rhythm followed by regulation phenomena. Until now the perception mechanism for the gravistimulus is unknown, but several findings indicate the involvement of mitochondria: A) During the impediment of respiration the Og-reaction is inhibited and the regulation is reduced. B) The response to a light stimulus and the following regulation phenomena strongly resemble the behavior during exposure to Og, the only difference is that the two reactions are directed into opposite directions. In the blue-light reaction a flavin of the mitochondrial matrix seems to be involved in the light perception. C) The contraction rhythm as well as its modulations are coupled to rhythmic changes in the levels of ATP and calcium ions, involving the mitochondria as sites of energy production and of Ca++-storage. - So the mitochondria could be the site of the regulation and they possibly are the receptor sites for the light and gravity stimuli. - Also the observation of a morphologic polarity of the slime mold's plasmodial strands has to be considered: Cross-sections reveal that the ectoplasmic wall surrounding the streaming endoplasm is much thinner on the physically lower side than on the upper side of the strand - this applies to strands lying on or hanging on a horizontal surface. So, in addition to the mitochondria, also the morphologic polarity may be involved in the perception mechanism of the observed gravisensitivity and of the recently established geotaxis. - The potential role of the nuclei and of the contractile elements in the perception of gravity is also discussed.

  4. Plastic Surgery and Acellular Dermal Matrix: Highlighting Trends from 1999 to 2013.

    PubMed

    Daar, David A; Gandy, Jessica R; Clark, Emily G; Mowlds, Donald S; Paydar, Keyianoosh Z; Wirth, Garrett A

    2016-05-01

    The last decade has ushered in a rapidly expanding global discussion regarding acellular dermal matrix (ADM) applications, economic analyses, technical considerations, benefits, and risks, with recent emphasis on ADM use in breast surgery. This study aims to evaluate global trends in ADM research using bibliometric analysis. The top nine Plastic Surgery journals were determined by impact factor (IF). Each issue of the nine journals between 1999 and 2013 was accessed to compile a database of articles discussing ADM. Publications were further classified by IF, authors' geographic location, study design, and level of evidence (LOE, I-V). Productivity index and productivity share were calculated for each region. In total, 256 ADM articles were accessed. The annual global publication volume increased significantly by 4.2 (0.87) articles per year (p<0.001), with a mean productivity index of 36.3 (59.0). The mean impact factor of the nine journals increased significantly from 0.61 (0.11) to 2.47 (0.99) from 1993 to 2013 (p<0.001). Despite this increase in the global ADM literature, the majority of research was of weaker LOE (level I: 2.29% and level II: 9.17%). USA contributed the most research (87%), followed by Asia (4.76%) and Western Europe (4.71%). USA contributed the greatest volume of research. Regarding clinical application of ADM, the majority of publications focused on ADM use in breast surgery, specifically breast reconstruction (154 articles, 60.2%). The majority of research was of lower LOE; thus, efforts should be made to strengthen the body of literature, particularly with regard to cost analysis. PMID:27579264

  5. Chondrogenesis of Human Infrapatellar Fat Pad Stem Cells on Acellular Dermal Matrix.

    PubMed

    Ye, Ken; Traianedes, Kathy; Choong, Peter F M; Myers, Damian E

    2016-01-01

    Acellular dermal matrix (ADM) has been in clinical use for decades in numerous surgical applications. The ability for ADM to promote cellular repopulation, revascularisation and tissue regeneration is well documented. Adipose stem cells have the ability to differentiate into mesenchymal tissue types, including bone and cartilage. The aim of this study was to investigate the potential interaction between ADM and adipose stem cells in vitro using TGFβ3 and BMP6. Human infrapatellar fat pad-derived adipose stem cells (IPFP-ASC) were cultured with ADM derived from rat dermis in chondrogenic (TGFβ3 and BMP6) medium in vitro for 2 and 4 weeks. Histology, qPCR, and immunohistochemistry were performed to assess for markers of chondrogenesis (collagen Type II, SOX9 and proteoglycans). At 4 weeks, cell-scaffold constructs displayed cellular changes consistent with chondrogenesis, with evidence of stratification of cell layers and development of a hyaline-like cartilage layer superficially, which stained positively for collagen Type II and proteoglycans. Significant cell-matrix interaction was seen between the cartilage layer and the ADM itself with seamless integration between each layer. Real time qPCR showed significantly increased COL2A1, SOX9, and ACAN gene expression over 4 weeks when compared to control. COL1A2 gene expression remained unchanged over 4 weeks. We believe that the principles that make ADM versatile and successful for tissue regeneration are applicable to cartilage regeneration. This study demonstrates in vitro the ability for IPFP-ASCs to undergo chondrogenesis, infiltrate, and interact with ADM. These outcomes serve as a platform for in vivo modelling of ADM for cartilage repair. PMID:26858950

  6. Ex vivo evaluation of acellular and cellular collagen-glycosaminoglycan flowable matrices.

    PubMed

    Hodgkinson, Tom; Bayat, Ardeshir

    2015-08-01

    Collagen-glycosaminoglycan flowable matrices (CGFM) are increasingly finding utility in a diversifying number of cutaneous surgical procedures. Cellular in-growth and vascularisation of CGFM remain rate-limiting steps, increasing cost and decreasing efficacy. Through in vitro and ex vivo culture methods, this study investigated the improvement of injectable CGFM by the incorporation of hyaluronan (HA) and viable human cells (primary human dermal fibroblasts (PHDFs) and bone marrow-derived mesenchymal stem cells (BM-MSCs)). Ex vivo investigations included the development and evaluation of a human cutaneous wound healing model for the comparison of dermal substitutes. Cells mixed into the Integra Flowable Wound Matrix (IFWM), a commercially available CGFM, were confirmed to be viable and proliferative through MTT assays (p  <  0.05). PHDFs proliferated with greater rapidity than BM-MSCs up to 1 week in culture (p  <  0.05), with PHDF proliferation further enhanced by HA supplementation (p  <  0.05). After scaffold mixing, gene expression was not significantly altered (qRT-PCR). PHDF and BM-MSC incorporation into ex vivo wound models significantly increased re-epithelialisation rate, with maximal effects observed for BM-MSC supplemented IFWM. HA supplementation to PHDF populated IFWM increased re-epithelialisation but had no significant effect on BM-MSC populated IFWM. In conclusion, when combined with PHDF, HA increased re-epithelialisation in IFWM. BM-MSC incorporation significantly improved re-epithelialisation in ex vivo models over acellular and PHDF populated scaffolds. Viable cell incorporation into IFWM has potential to significantly benefit wound healing in chronic and acute cutaneous injuries by allowing a point-of-care matrix to be formed from autologous or allogenic cells and bioactive molecules. PMID:26181360

  7. Laminin Functionalized Biomimetic Nanofibers For Nerve Tissue Engineering

    PubMed Central

    Junka, Radoslaw; Valmikinathan, Chandra M; Kalyon, Dilhan M; Yu, Xiaojun

    2013-01-01

    Large-gap peripheral nerve injuries present a significant challenge for nerve regeneration due to lack of suitable grafts, insufficient cell penetration, and repair. Biomimetic nanofibrous scaffolds, functionalized on the surface with extracellular matrix proteins, can lead to novel therapies for repair and regeneration of damaged peripheral nerves. Here, nanofibrous scaffolds electrospun from blends of poly(caprolactone) (PCL) and chitosan were fabricated. Taking advantage of the amine groups on the chitosan, the surface of the scaffolds were functionalized with laminin by carbodiimide based crosslinking. Crosslinking allowed laminin to be attached to the surfaces of the PCL-chitosan nanofibers at relatively high concentrations that were not possible using conventional adsorption methods. The nanofibrous meshes were tested for wettability, mechanical properties and cell attachment and proliferation. Blending of chitosan with PCL provided more favorable surfaces for attachment of Schwann cells due to the reduction of the contact angle in comparison to neat PCL. Proliferation rates of Schwann cells grown on PCL-chitosan scaffolds with crosslinked laminin were significantly higher than the rates for PCL-chitosan nanofibrous matrices with adsorbed laminin. PCL-chitosan scaffolds with modified surfaces via crosslinking of laminin could potentially serves as versatile substrates with excellent mechanical and surface properties for in vivo cell delivery for nerve tissue engineering applications. PMID:24083073

  8. Cranial Nerve II: Vision.

    PubMed

    Gillig, Paulette Marie; Sanders, Richard D

    2009-09-01

    This article contains a brief review of the anatomy of the visual system, a survey of diseases of the retina, optic nerve and lesions of the optic chiasm, and other visual field defects of special interest to the psychiatrist. It also includes a presentation of the corticothalamic mechanisms, differential diagnosis, and various manifestations of visual illusions, and simple and complex visual hallucinations, as well as the differential diagnoses of these various visual phenomena. PMID:19855858

  9. Polyether/Polyester Graft Copolymers

    NASA Technical Reports Server (NTRS)

    Bell, Vernon L., Jr.; Wakelyn, N.; Stoakley, D. M.; Proctor, K. M.

    1986-01-01

    Higher solvent resistance achieved along with lower melting temperature. New technique provides method of preparing copolymers with polypivalolactone segments grafted onto poly (2,6-dimethyl-phenylene oxide) backbone. Process makes strong materials with improved solvent resistance and crystalline, thermally-reversible crosslinks. Resulting graft copolymers easier to fabricate into useful articles, including thin films, sheets, fibers, foams, laminates, and moldings.

  10. Gluteus augmentation with fat grafting.

    PubMed

    Perén, P A; Gómez, J B; Guerrerosantos, J; Salazar, C A

    2000-01-01

    This study presents the authors' experience with gluteus augmentation with autologus fat grafts and liposuction methods, having recorded the evolution of gluteus reshaping with autologus intramuscular fat graft injections for the past 5 years. Preoperative shape is discussed and patient evaluations, operative techniques, postoperative management, and longterm results are emphasized. PMID:11246428

  11. Grafting effects on vegetable quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetable grafting began in the 1920s to control soil-borne disease. It is now a common practice in Asia, parts of Europe, and the Middle East. In Japan and Korea most of the cucurbits and tomatoes (Lycopersicon esculentum Mill.) grown are grafted. This practice is rare in the U.S. and there have...

  12. Listeria monocytogenes Endovascular Graft Infection

    PubMed Central

    Heysell, Scott K.; Hughes, Molly A.

    2016-01-01

    Although best managed by surgical resection, we present a case of Listeria monocytogenes endovascular graft infection alternatively treated with graft retention and antibiotic induction followed by a lifelong suppressive course. The epidemiological, pathological, and clinical features of this unique entity are reviewed. PMID:26835477

  13. Fabrication and characterisation of biomimetic, electrospun gelatin fibre scaffolds for tunica media-equivalent, tissue engineered vascular grafts.

    PubMed

    Elsayed, Y; Lekakou, C; Labeed, F; Tomlins, P

    2016-04-01

    It is increasingly recognised that biomimetic, natural polymers mimicking the extracellular matrix (ECM) have low thrombogenicity and functional motifs that regulate cell-matrix interactions, with these factors being critical for tissue engineered vascular grafts especially grafts of small diameter. Gelatin constitutes a low cost substitute of soluble collagen but gelatin scaffolds so far have shown generally low strength and suture retention strength. In this study, we have devised the fabrication of novel, electrospun, multilayer, gelatin fibre scaffolds, with controlled fibre layer orientation, and optimised gelatin crosslinking to achieve not only compliance equivalent to that of coronary artery but also for the first time strength of the wet tubular acellular scaffold (swollen with absorbed water) same as that of the tunica media of coronary artery in both circumferential and axial directions. Most importantly, for the first time for natural scaffolds and in particular gelatin, high suture retention strength was achieved in the range of 1.8-1.94 N for wet acellular scaffolds, same or better than that for fresh saphenous vein. The study presents the investigations to relate the electrospinning process parameters to the microstructural parameters of the scaffold, which are further related to the mechanical performance data of wet, crosslinked, electrospun scaffolds in both circumferential and axial tubular directions. The scaffolds exhibited excellent performance in human smooth muscle cell (SMC) proliferation, with SMCs seeded on the top surface adhering, elongating and aligning along the local fibres, migrating through the scaffold thickness and populating a transverse distance of 186 μm and 240 μm 9 days post-seeding for scaffolds of initial dry porosity of 74 and 83%, respectively. PMID:26838874

  14. Synthesis and physicochemical characterization of a series of hemoglobin-based oxygen carriers: objective comparison between cellular and acellular types.

    PubMed

    Sakai, H; Yuasa, M; Onuma, H; Takeoka, S; Tsuchida, E

    2000-01-01

    A series of hemoglobin (Hb)-based O(2) carriers, acellular and cellular types, were synthesized and their physicochemical characteristics were compared. The acellular type includes intramolecularly cross-linked Hb (XLHb), polyoxyethylene (POE)-conjugated pyridoxalated Hb (POE-PLP-Hb), hydroxyethylstarch-conjugated Hb (HES-XLHb), and glutaraldehyde-polymerized XLHb (Poly-XLHb). The cellular type is Hb-vesicles (HbV) of which the surface is modified with POE (POE-HbV). Their particle diameters are 7 +/- 2, 22 +/- 2, 47 +/- 17, 68 +/- 24, and 224 +/- 76 nm, respectively, thus all the materials penetrate across membrane filters with 0.4 microm pore size, though only the POE-HbV cannot penetrate across the filter with 0.2 microm pore size. These characteristics of permeability are important to consider an optimal particle size in microcirculation in vivo. POE-PLP-Hb ([Hb] = 5 g/dL) showed viscosity of 6.1 cP at 332 s(-1) and colloid osmotic pressure (COP) of 70.2 Torr, which are beyond the physiological conditions (human blood, viscosity = 3-4 cP, COP = ca. 25 Torr). XLHb and Poly-XLHb showed viscosities of 1.0 and 1.5 cp, respectively, which are significantly lower than that of blood. COP of POE-HbV is regulated to 20 Torr in 5% human serum albumin (HSA). HES-XLHb and POE-HbV/HSA showed comparable viscosity with human blood. Microscopic observation of human red blood cells (RBC) after mixing blood with POE-PLP-Hb or HES-XLHb disclosed aggregates of RBC, a kind of sludge, indicating a strong interaction with RBC, which is anticipated to modify peripheral blood flow in vivo. On the other hand, XLHb and POE-HbV showed no rouleaux or aggregates of RBC. The acellular Hbs (P(50) = 14-32 Torr) have their specific O(2) affinities determined by their structures, while that of the cellular POE-HbV is regulated by coencapsulating an appropriate amount of an allosteric effector (e.g., P(50) = 18, 32 Torr). These differences in physicochemical characteristics between the acellular

  15. Optic nerve hypoplasia.

    PubMed

    Kaur, Savleen; Jain, Sparshi; Sodhi, Harsimrat B S; Rastogi, Anju; Kamlesh

    2013-05-01

    Optic nerve hypoplasia (ONH) is a congenital anomaly of the optic disc that might result in moderate to severe vision loss in children. With a vast number of cases now being reported, the rarity of ONH is obviously now refuted. The major aspects of ophthalmic evaluation of an infant with possible ONH are visual assessment, fundus examination, and visual electrophysiology. Characteristically, the disc is small, there is a peripapillary double-ring sign, vascular tortuosity, and thinning of the nerve fiber layer. A patient with ONH should be assessed for presence of neurologic, radiologic, and endocrine associations. There may be maternal associations like premature births, fetal alcohol syndrome, maternal diabetes. Systemic associations in the child include endocrine abnormalities, developmental delay, cerebral palsy, and seizures. Besides the hypoplastic optic nerve and chiasm, neuroimaging shows abnormalities in ventricles or white- or gray-matter development, septo-optic dysplasia, hydrocephalus, and corpus callosum abnormalities. There is a greater incidence of clinical neurologic abnormalities in patients with bilateral ONH (65%) than patients with unilateral ONH. We present a review on the available literature on the same to urge caution in our clinical practice when dealing with patients with ONH. Fundus photography, ocular coherence tomography, visual field testing, color vision evaluation, neuroimaging, endocrinology consultation with or without genetic testing are helpful in the diagnosis and management of ONH. (Method of search: MEDLINE, PUBMED). PMID:24082663

  16. [Stent Grafting for Aortic Dissection].

    PubMed

    Uchida, Naomichi

    2016-07-01

    The purpose of stent graft for aortic dissection is to terminate antegrade blood flow into the false lumen through primary entry. Early intervention for primary entry makes excellent aortic remodeling and emergent stent grafting for complicated acute type B aortic dissection is supported as a class I. On the other hand stent grafting for chronic aortic dissection is controversial. Early stent grafting is considered with in 6 months after on-set if the diameter of the descending aorta is more than 40 mm. Additional interventions for residual false lumen on the downstream aorta are still required. Stent graft for re-entry, candy-plug technique, and double stenting, other effective re-interventions were reported. Best treatment on the basis of each anatomical and physical characteristics should be selected in each institution. Frozen elephant trunk is alternative procedure for aortic dissection without the need to take account of proximal anatomical limitation and effective for acute type A aortic dissection. PMID:27440026

  17. ACL Reconstruction: Choosing the Graft

    PubMed Central

    Cerulli, Giuliano; Placella, Giacomo; Sebastiani, Enrico; Tei, Matteo Maria; Speziali, Andrea; Manfreda, Francesco

    2013-01-01

    Summary Rupture of the anterior cruciate ligament is one of the most common ligament injuries in sports traumatology. The need for surgical anterior cruciate ligament reconstruction is justified by its anatomical characteristics. Key considerations when choosing a graft include the potential for bone integration and the risk of failure. Bone sclerosis around the tunnel affects the integration of the graft. For this reason, one aspect upon which orthopedic surgeons should focus is the biology of the bone-graft interface. Although the BPTB graft is still used, hamstrings and synthetic grafts have become increasingly widespread and popular over the years. An allograft certainly requires more long-term follow-up to validate its use in response to functional, clinical and biological requirements. PMID:25606507

  18. The treatment of peripheral nerve injuries using irradiated allografts and temporary host immunosuppression (in a rat model)

    SciTech Connect

    Easterling, K.J.; Trumble, T.E. )

    1990-10-01

    Irradiation of allografts prior to transplantation and host immunosuppression with cyclosporin-A were studied separately and in combination as means of lessening the rejection of transplanted peripheral nerve tissue. Lewis and Brown Norway rats were used in the animal model, as they differ at both major and minor histocompatibility loci. Sciatic nerve grafts (2.5 cm) were used and the animals were followed for 16 weeks after nerve grafting. The outcome was studied by functional measurements (sensory testing, gait analysis, joint flexion contracture, and muscle weight), as well as by measurements of biochemical and histologic parameters (hydroxyproline concentration and axon counts, respectively). Sensory testing was not reliable because of crossover innervation by the saphenous nerve. Evaluation by standard gait-testing techniques was found to be unsatisfactory. However, the allografted animals receiving cyclosporin-A had significantly smaller flexion contractures, compared to the allografted animals without immunosuppression (17 degrees +/- 12 degrees vs. 44 degrees +/- 13 degrees and 51 degrees +/- 13 degrees, p less than 0.005). Allografted animals receiving short-term cyclosporin-A had contractures that were not significantly different from those seen in isografted control animals (17 degrees +/- 12 degrees vs. 22 degrees +/- 15 degrees, NS). Muscle hydroxyproline concentration analysis revealed a lower hydroxyproline concentration among the allografted groups that received irradiated allografts, compared to groups receiving nonirradiated allogeneic grafts. The studies of muscle hydroxyproline concentration and muscle weight both showed substantial reinnervation, even in allografted animals without pretreatment of the grafts or immunosuppression of the recipient animal.

  19. Radiation grafting on natural films

    NASA Astrophysics Data System (ADS)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37-40 N mm-1) and puncture deformation (PD=6.5-9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282-296 N mm-1 and PD of 5.0-5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films.

  20. Combination of Local Transplantation of In Vitro Bone-marrow Stromal Cells and Pulsed Electromagnetic Fields Accelerate Functional Recovery of Transected Sciatic Nerve Regeneration: A Novel Approach in Transected Nerve Repair.

    PubMed

    Mohammadi, Rahim; Mahmoodzadeh, Sirvan

    2015-01-01

    Effect of combination of undifferentiated bone marrow stromal cells (BMSCs) and pulsed electromagnetic fields (PEMF) on transected sciatic nerve regeneration was assessed in rats. A 10 mm nerve segment was excised and a vein graft was used to bridge the gap. Twenty microliter undifferentiated BMSCs (2× 107 cells /mL) were administered into the graft inBMSC group with no exposure to PEMF. In BMSC/PEMF group the whole body was exposed to PEMF (0.3 mT, 2Hz) for 4h/day within 1-5 days. In PEMF group the transected nerve was bridged and phosphate buffered saline was administered into the graft. In authograft group (AUTO), the transected nervesegments were reimplanted reversely and the whole body was exposed to PEMF. The regenerated nerve fibers were studied within 12 weeks after surgery. Behavioral, functional, electrophysiological, biomechanical, gastrocnemius muscle mass findings, morphometric indices and immuonohistochemical reactions confirmed faster recovery of regenerated axons in BMSC/PEMF group compared to those in the other groups (P<0.05). The use of undifferentiated BMSCs with whole body exposure to PEMF improved functional recovery. Combination of local transplantation of in vitro bone-marrow stromal cells and pulsed electromagnetic fields could be considered as an effective, safe and tolerable treatment for peripheral nerve repair in clinical practice. PMID:26044808

  1. Neuromuscular Ultrasound of Cranial Nerves

    PubMed Central

    Tawfik, Eman A.; Cartwright, Michael S.

    2015-01-01

    Ultrasound of cranial nerves is a novel subdomain of neuromuscular ultrasound (NMUS) which may provide additional value in the assessment of cranial nerves in different neuromuscular disorders. Whilst NMUS of peripheral nerves has been studied, NMUS of cranial nerves is considered in its initial stage of research, thus, there is a need to summarize the research results achieved to date. Detailed scanning protocols, which assist in mastery of the techniques, are briefly mentioned in the few reference textbooks available in the field. This review article focuses on ultrasound scanning techniques of the 4 accessible cranial nerves: optic, facial, vagus and spinal accessory nerves. The relevant literatures and potential future applications are discussed. PMID:25851889

  2. Ultrasound guidance of uncommon nerve blocks

    PubMed Central

    Thallaj, Ahmed

    2011-01-01

    In the past nerve stimulation was considered the standard tool for anesthesiologists to locate the peripheral nerve for nerve blocks. However, with the recent introduction of ultrasound (US) technology for regional anesthesia, the use of nerve stimulation has become a rarity nowadays. There is a growing interest by most anesthesiologists in using US for nerve blocks because of its simplicity and accuracy. US is now available in most hospitals practicing regional anesthesia and is a popular tool for performance of nerve blocks. Although nerve stimulation became a rarity, however the use of it is now limited to identify small nerve structures, such as greater auricular nerve and medial antebrachial cutaneous nerve of the forearm. However, in this review article we discuss the role of ultrasonography for greater auricular and antebrachial cutaneous nerve blocks, which could replace nerve stimulation technique. We look at the available literature on the role of US for the performance of uncommon nerve blocks and its benefits. PMID:22144927

  3. Dermal papilla cells improve the wound healing process and generate hair bud-like structures in grafted skin substitutes using hair follicle stem cells.

    PubMed

    Leirós, Gustavo José; Kusinsky, Ana Gabriela; Drago, Hugo; Bossi, Silvia; Sturla, Flavio; Castellanos, María Lía; Stella, Inés Yolanda; Balañá, María Eugenia

    2014-10-01

    Tissue-engineered skin represents a useful strategy for the treatment of deep skin injuries and might contribute to the understanding of skin regeneration. The use of dermal papilla cells (DPCs) as a dermal component in a permanent composite skin with human hair follicle stem cells (HFSCs) was evaluated by studying the tissue-engineered skin architecture, stem cell persistence, hair regeneration, and graft-take in nude mice. A porcine acellular dermal matrix was seeded with HFSCs alone and with HFSCs plus human DPCs or dermal fibroblasts (DFs). In vitro, the presence of DPCs induced a more regular and multilayered stratified epidermis with more basal p63-positive cells and invaginations. The DPC-containing constructs more accurately mimicked the skin architecture by properly stratifying the differentiating HFSCs and developing a well-ordered epithelia that contributed to more closely recapitulate an artificial human skin. This acellular dermal matrix previously repopulated in vitro with HFSCs and DFs or DPCs as the dermal component was grafted in nude mice. The presence of DPCs in the composite substitute not only favored early neovascularization, good assimilation and remodeling after grafting but also contributed to the neovascular network maturation, which might reduce the inflammation process, resulting in a better healing process, with less scarring and wound contraction. Interestingly, only DPC-containing constructs showed embryonic hair bud-like structures with cells of human origin, presence of precursor epithelial cells, and expression of a hair differentiation marker. Although preliminary, these findings have demonstrated the importance of the presence of DPCs for proper skin repair. PMID:25161315

  4. Dermal Papilla Cells Improve the Wound Healing Process and Generate Hair Bud-Like Structures in Grafted Skin Substitutes Using Hair Follicle Stem Cells

    PubMed Central

    Leirós, Gustavo José; Kusinsky, Ana Gabriela; Drago, Hugo; Bossi, Silvia; Sturla, Flavio; Castellanos, María Lía; Stella, Inés Yolanda

    2014-01-01

    Tissue-engineered skin represents a useful strategy for the treatment of deep skin injuries and might contribute to the understanding of skin regeneration. The use of dermal papilla cells (DPCs) as a dermal component in a permanent composite skin with human hair follicle stem cells (HFSCs) was evaluated by studying the tissue-engineered skin architecture, stem cell persistence, hair regeneration, and graft-take in nude mice. A porcine acellular dermal matrix was seeded with HFSCs alone and with HFSCs plus human DPCs or dermal fibroblasts (DFs). In vitro, the presence of DPCs induced a more regular and multilayered stratified epidermis with more basal p63-positive cells and invaginations. The DPC-containing constructs more accurately mimicked the skin architecture by properly stratifying the differentiating HFSCs and developing a well-ordered epithelia that contributed to more closely recapitulate an artificial human skin. This acellular dermal matrix previously repopulated in vitro with HFSCs and DFs or DPCs as the dermal component was grafted in nude mice. The presence of DPCs in the composite substitute not only favored early neovascularization, good assimilation and remodeling after grafting but also contributed to the neovascular network maturation, which might reduce the inflammation process, resulting in a better healing process, with less scarring and wound contraction. Interestingly, only DPC-containing constructs showed embryonic hair bud-like structures with cells of human origin, presence of precursor epithelial cells, and expression of a hair differentiation marker. Although preliminary, these findings have demonstrated the importance of the presence of DPCs for proper skin repair. PMID:25161315

  5. Safety profile of sural nerve in posterolateral approach to the ankle joint: MRI study.

    PubMed

    Ellapparadja, Pregash; Husami, Yaya; McLeod, Ian

    2014-05-01

    The posterolateral approach to ankle joint is well suited for ORIF of posterior malleolar fractures. There are no major neurovascular structures endangering this approach other than the sural nerve. The sural nerve is often used as an autologous peripheral nerve graft and provides sensation to the lateral aspect of the foot. The aim of this paper is to measure the precise distance of the sural nerve from surrounding soft tissue structures so as to enable safe placement of skin incision in posterolateral approach. This is a retrospective image review study involving 64 MRI scans. All measurements were made from Axial T1 slices. The key findings of the paper is the safety window for the sural nerve from the lateral border of tendoachilles (TA) is 7 mm, 1.3 cm and 2 cm at 3 cm above ankle joint, at the ankle joint and at the distal tip of fibula respectively. Our study demonstrates the close relationship of the nerve in relation to TA and fibula in terms of exact measurements. The safety margins established in this study should enable the surgeon in preventing endangerment of the sural nerve encountered in this approach. PMID:24158742

  6. Evidence-based outcomes following inferior alveolar and lingual nerve injury and repair: a systematic review.

    PubMed

    Kushnerev, E; Yates, J M

    2015-10-01

    The inferior alveolar nerve (IAN) and lingual (LN) are susceptible to iatrogenic surgical damage. Systematically review recent clinical evidence regarding IAN/LN repair methods and to develop updated guidelines for managing injury. Recent publications on IAN/LN microsurgical repair from Medline, Embase and Cochrane Library databases were screened by title/abstract. Main texts were appraised for exclusion criteria: no treatment performed or results provided, poor/lacking procedural description, cohort <3 patients. Of 366 retrieved papers, 27 were suitable for final analysis. Treatment type for injured IANs/LNs depended on injury type, injury timing, neurosensory disturbances and intra-operative findings. Best functional nerve recovery occurred after direct apposition and suturing if nerve ending gaps were <10 mm; larger gaps required nerve grafting (sural/greater auricular nerve). Timing of microneurosurgical repair after injury remains debated. Most authors recommend surgery when neurosensory deficit shows no improvement 90 days post-diagnosis. Nerve transection diagnosed intra-operatively should be repaired in situ; minor nerve injury repair can be delayed. No consensus exists regarding optimal methods and timing for IAN/LN repair. We suggest a schematic guideline for treating IAN/LN injury, based on the most current evidence. We acknowledge that additional RCTs are required to provide definitive confirmation of optimal treatment approaches. PMID:26059454

  7. Management of a full-thickness burn to the foot following sciatic nerve palsy secondary to primary total hip replacement.

    PubMed

    Jabir, Shehab; Frew, Quentin; El-Muttardi, Naguib; Dziewulski, Peter

    2013-01-01

    Sciatic nerve palsy following total hip replacement is a rare but serious complication. The neurological sequelae that follow range from pure sensory loss to combined motor and sensory loss involving most of the lower limb. The loss of nociceptive feedback predisposes patients to accidental damage to the lower limb. We present the case of a lady with sciatic nerve palsy who sustained full-thickness burn injuries to her foot via a hot water bottle. The dilemma between debridement and grafting following a recent history of surgical trauma (ie, total hip replacement) versus secondary healing via dressings and regular review is discussed. Although grafting is the standard treatment in such burns, we recommend secondary healing over grafting provided the burns are not extensive. This enables potential recovery of sensation and reduces operative trauma to the limb which may retard resolution of the neuropraxia. PMID:23595171

  8. Enhancement of peripheral nerve regeneration due to treadmill training and electrical stimulation is dependent on androgen receptor signaling.

    PubMed

    Thompson, Nicholas J; Sengelaub, Dale R; English, Arthur W

    2014-05-01

    Moderate exercise in the form of treadmill training and brief electrical nerve stimulation both enhance axon regeneration after peripheral nerve injury. Different regimens of exercise are required to enhance axon regeneration in male and female mice (Wood et al.: Dev Neurobiol 72 (2012) 688-698), and androgens are suspected to be involved. We treated mice with the androgen receptor blocker, flutamide, during either exercise or electrical stimulation, to evaluate the role of androgen receptor signaling in these activity-based methods of enhancing axon regeneration. The common fibular (CF) and tibial (TIB) nerves of thy-1-YFP-H mice, in which axons in peripheral nerves are marked by yellow fluorescent protein (YFP), were transected and repaired using CF and TIB nerve grafts harvested from non-fluorescent donor mice. Silastic capsules filled with flutamide were implanted subcutaneously to release the drug continuously. Exercised mice were treadmill trained 5 days/week for 2 weeks, starting on the third day post-transection. For electrical stimulation, the sciatic nerve was stimulated continuously for 1 h prior to nerve transection. After 2 weeks, lengths of YFP+ profiles of regenerating axons were measured from harvested nerves. Both exercise and electrical stimulation enhanced axon regeneration, but this enhancement was blocked completely by flutamide treatments. Signaling through androgen receptors is necessary for the enhancing effects of treadmill exercise or electrical stimulation on axon regeneration in cut peripheral nerves. PMID:24293191

  9. Electrical stimulation accelerates axonal and functional peripheral nerve regeneration across long gaps.

    PubMed

    Haastert-Talini, Kirsten; Schmitte, Ruth; Korte, Nele; Klode, Dorothee; Ratzka, Andreas; Grothe, Claudia

    2011-04-01

    Short-term low-frequency electrical stimulation (ESTIM) of proximal peripheral nerve stumps prior to end-to-end coaptation or tubular bridging of small distances has been reported to increase preferential motor reinnervation and functional motor recovery in animal models and human patients undergoing carpal tunnel release surgery. We investigated the effects of ESTIM on regeneration across rat sciatic nerve gaps, which exceed distances that allow spontaneous regeneration. Three different reconstruction approaches were combined with ESTIM in the experimental groups. Nerve gaps (13 mm) were bridged using (I) nerve autotransplantation, (II) transplantation of differentially filled silicone tubes, or (III) transplantation of tubular grafts containing fibroblast growth factor-2 overexpressing Schwann cells (SCs) for gene therapy. The regeneration outcome was followed for up to 8 weeks, and functionally as well as histomorphometrically analyzed in comparison to non-stimulated control groups. Combining ESTIM with nerve autotransplantation significantly increased the nerve fiber density in the regenerated nerve, and the grade of functional recovery as detected by electrodiagnostic recordings from the gastrocnemius muscle. The combination of ESTIM with transplantation of naïve SCs increased the regeneration of gap-bridging nerve tissue. Although macroscopic tissue regeneration was not further improved after combining ESTIM with FGF-2(21/23-kD) gene therapy, the latter resulted in a high rate of regenerated nerves that functionally reconnected to the target muscle. Based on our results, brief ESTIM shows high potential to accelerate axonal as well as functional (motor and sensory) outcomes in the clinical setting of peripheral nerve gap reconstruction in human patients. PMID:21265597

  10. Effect of local administration of platelet-derived growth factor B on functional recovery of peripheral nerve regeneration: A sciatic nerve transection model

    PubMed Central

    Golzadeh, Atefeh; Mohammadi, Rahim

    2016-01-01

    Background: Effects of platelet-derived growth factor B (PDGF-B) on peripheral nerve regeneration was studied using a rat sciatic nerve transection model. Materials and Methods: Forty-five male, white Wistar rats were divided into three experimental groups (n = 15), randomly: Normal control group (NC), silicon group (SIL), and PDGF-B treated group (SIL/PDGF). In NC group, left sciatic nerve was exposed through a gluteal muscle incision and after homeostasis muscle was sutured. In the SIL group, the left sciatic nerve was exposed in the same way and transected proximal to tibio-peroneal bifurcation leaving a 10-mm gap. Proximal and distal stumps were each inserted into a silicone conduit and filled with 10 μL phosphate buffered solution. In SIL/PDGF group, the silicon conduit was filled with 10 μL PDGF-B (0.5 ng/mL). Each group was subdivided into three subgroups of five and were studied in 4, 8, 12 weeks after surgery. Results: Behavioral testing, sciatic nerve functional study, gastrocnemius muscle mass, and histomorphometric studies showed earlier regeneration of axons in SIL/PDGF than in SIL group (P < 0.05). Conclusion: Local administration of PDGF-B combined with silicon grafting could accelerate functional recovery and may have clinical implications for the surgical management of patients after facial nerve transection. PMID:27274342

  11. Sustained release of VEGF from PLGA nanoparticles embedded thermo-sensitive hydrogel in full-thickness porcine bladder acellular matrix

    NASA Astrophysics Data System (ADS)

    Geng, Hongquan; Song, Hua; Qi, Jun; Cui, Daxiang

    2011-12-01

    We fabricated a novel vascular endothelial growth factor (VEGF)-loaded poly(lactic- co-glycolic acid) (PLGA)-nanoparticles (NPs)-embedded thermo-sensitive hydrogel in porcine bladder acellular matrix allograft (BAMA) system, which is designed for achieving a sustained release of VEGF protein, and embedding the protein carrier into the BAMA. We identified and optimized various formulations and process parameters to get the preferred particle size, entrapment, and polydispersibility of the VEGF-NPs, and incorporated the VEGF-NPs into the (poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (Pluronic®) F127 to achieve the preferred VEGF-NPs thermo-sensitive gel system. Then the thermal behavior of the system was proven by in vitro and in vivo study, and the kinetic-sustained release profile of the system embedded in porcine bladder acellular matrix was investigated. Results indicated that the bioactivity of the encapsulated VEGF released from the NPs was reserved, and the VEGF-NPs thermo-sensitive gel system can achieve sol-gel transmission successfully at appropriate temperature. Furthermore, the system can create a satisfactory tissue-compatible environment and an effective VEGF-sustained release approach. In conclusion, a novel VEGF-loaded PLGA NPs-embedded thermo-sensitive hydrogel in porcine BAMA system is successfully prepared, to provide a promising way for deficient bladder reconstruction therapy.

  12. The initial attachment of cemental fibrils to the root dentin surface in acellular and cellular cementogenesis in rat molars.

    PubMed

    Yamamoto, T; Domon, T; Takahashi, S; Islam, M N; Suzuki, R

    2001-03-01

    To elucidate the initial attachment mechanism of cemental fibrils to the root dentin surface in acellular and cellular cementogenesis, developing rat molars were observed by light microscopy and scanning electron microscopy combined with NaOH maceration. The NaOH maceration was used to observe details of the positional association of cemental and dentinal fibrils during cementogenesis. An initial hematoxylin stained, cementum layer began to form on the root dentin surface with the first dentin mineralization in both acellular and cellular cementogenesis. The initial attachment of cemental fibrils to the dentin surface also began at this point. At the initial attachment the intermingling of cemental and dentinal fibrils occurred only in places. With advanced cementogenesis the initial cementum layer became the fibril-poor cemento-dentinal junction. This suggests that cemental fibrils attach on the initial cementum layer, and not directly on dentinal fibrils, so that the layer results in the fibril-poor cemento-dentinal junction. The present study suggests that an intervening adhesive is necessary for the cemento-dentinal attachment at any stage of cementogenesis in rat molars. PMID:11325058

  13. Pancreatic acellular matrix supports islet survival and function in a synthetic tubular device: in vitro and in vivo studies.

    PubMed

    De Carlo, E; Baiguera, S; Conconi, M T; Vigolo, S; Grandi, C; Lora, S; Martini, C; Maffei, P; Tamagno, G; Vettor, R; Sicolo, N; Parnigotto, P P

    2010-02-01

    Increasing pancreatic islet survival and function is a starting point for obtaining a valuable bioartificial pancreas for the treatment of type 1 diabetes. In this context, decellularized matrices, obtained after the removal of tissue cellular part, are known to support in vitro adhesion, growth, and function of several cell types. We demonstrate that a homologous acellular pancreatic matrix is a suitable scaffold for rat islet cultures maintaining their long-term viability and function. Islets adhered to the pancreatic matrix showed a constant glucose-induced insulin release during long-term in vitro incubation, while islets cultured without a matrix or on the liver matrix showed a progressive reduction. In order to obtain implantable devices, acellular matrix/islet cultures were entrapped into poly(vinyl alcohol) (PVA)/ poly(ethylene glycol) (PEG) tubes obtained by the freezing/thawing procedure. Under this condition, an in vitro constant insulin release was detected. The devices were then implanted into diabetic rats where reduced insulin requirement was noted suggesting insulin secretory activity of islets contained in the device. Indeed, immunofluorescence confirmed the presence of insulin- and glucagon-producing cells into the explanted devices. These data show that PVA/PEG semi-permeable membrane can obtain devices that restore, at least in part, insulin secretion. PMID:20043127

  14. Surgical Outcomes of Deep Superior Sulcus Augmentation Using Acellular Human Dermal Matrix in Anophthalmic or Phthisis Socket.

    PubMed

    Cho, Won-Kyung; Jung, Su-Kyung; Paik, Ji-Sun; Yang, Suk-Woo

    2016-07-01

    Patients with anophthalmic or phthisis socket suffer from cosmetic problems. To resolve those problems, the authors present the surgical outcomes of deep superior sulcus (DSS) augmentation using acellular dermal matrix in patients with anophthalmic or phthisis socket. The authors retrospectively reviewed anophthalmic or phthisis patients who underwent surgery for DSS augmentation using acellular dermal matrix. To evaluate surgical outcomes, the authors focused on 3 aspects: the possibility of wearing contact prosthesis, the degree of correction of the DSS, and any surgical complications. The degree of correction of DSS was classified as excellent: restoration of superior sulcus enough to remove sunken sulcus shadow; fair: gain of correction effect but sunken shadow remained; or fail: no effect of correction at all. Ten eyes of 10 patients were included. There was a mean 21.3 ± 37.1-month period from evisceration or enucleation to the operation for DSS augmentation. All patients could wear contact prosthesis after the operation (100%). The degree of correction was excellent in 8 patients (80%) and fair in 2. Three of 10 (30%) showed complications: eyelid entropion, upper eyelid multiple creases, and spontaneous wound dehiscence followed by inflammation after stitch removal. Uneven skin surface and paresthesia in the forehead area of the affected eye may be observed after surgery. The overall surgical outcomes were favorable, showing an excellent degree of correction of DSS and low surgical complication rates. This procedure is effective for patients who have DSS in the absence or atrophy of the eyeball. PMID:27258711

  15. Nerve blocks for chronic pain.

    PubMed

    Hayek, Salim M; Shah, Atit

    2014-10-01

    Nerve blocks are often performed as therapeutic or palliative interventions for pain relief. However, they are often performed for diagnostic or prognostic purposes. When considering nerve blocks for chronic pain, clinicians must always consider the indications, risks, benefits, and proper technique. Nerve blocks encompass a wide variety of interventional procedures. The most common nerve blocks for chronic pain and that may be applicable to the neurosurgical patient population are reviewed in this article. This article is an introduction and brief synopsis of the different available blocks that can be offered to a patient. PMID:25240668

  16. Nerve conduction and electromyography studies.

    PubMed

    Kane, N M; Oware, A

    2012-07-01

    Nerve conduction studies (NCS) and electromyography (EMG), often shortened to 'EMGs', are a useful adjunct to clinical examination of the peripheral nervous system and striated skeletal muscle. NCS provide an efficient and rapid method of quantifying nerve conduction velocity (CV) and the amplitude of both sensory nerve action potentials (SNAPs) and compound motor action potentials (cMAPs). The CV reflects speed of propagation of action potentials, by saltatory conduction, along large myelinated axons in a peripheral nerve. The amplitude of SNAPs is in part determined by the number of axons in a sensory nerve, whilst amplitude of cMAPs reflects integrated function of the motor axons, neuromuscular junction and striated muscle. Repetitive nerve stimulation (RNS) can identify defects of neuromuscular junction (NMJ) transmission, pre- or post-synaptic. Needle EMG examination can detect myopathic changes in muscle and signs of denervation. Combinations of these procedures can establish if motor and/or sensory nerve cell bodies or peripheral nerves are damaged (e.g. motor neuronopathy, sensory ganglionopathy or neuropathy), and also indicate if the primary target is the axon or the myelin sheath (i.e. axonal or demyelinating neuropathies). The distribution of nerve damage can be determined as either generalised, multifocal (mononeuropathy multiplex) or focal. The latter often due to compression at the common entrapment sites (such as the carpal tunnel, Guyon's canal, cubital tunnel, radial groove, fibular head and tarsal tunnel, to name but a few of the reported hundred or so 'entrapment neuropathies'). PMID:22614870

  17. Secondary alveolar bone grafting: our experience with olecranon bone graft.

    PubMed

    Nadal, Emmanuela; Sabás, Mariana; Dogliotti, Pedro; Espósito, Raquel

    2010-03-01

    Management of alveolar cleft has dramatically changed during the last century: secondary alveolar bone grafting is now an integral part of cleft palate and craniofacial center's protocols. The objectives of alveolar repair and bone grafting are as follows: providing a continuous and stable maxillary dental arch, closure of oronasal fistulae, adequate bone for tooth eruption or orthodontic movement, and nasal base support, improving facial aesthetic. Although cancellous iliac bone is the donor site selected more frequently, bone grafts harvested from different sites have been advocated to decrease donor site morbidity.The aim of this study was to propose and evaluate the use of olecranon as a donor site in 24 patients with secondary alveolar cleft. The graft is taken as a single piece to fit the alveolar cleft defect, and it includes periosteum and corticocancellous bone to improve early vascularization and greater volume maintenance. PMID:20186086

  18. Nerve-pulse interactions

    SciTech Connect

    Scott, A.C.

    1982-01-01

    Some recent experimental and theoretical results on mechanisms through which individual nerve pulses can interact are reviewed. Three modes of interactions are considered: (1) interaction of pulses as they travel along a single fiber which leads to velocity dispersion; (2) propagation of pairs of pulses through a branching region leading to quantum pulse code transformations; and (3) interaction of pulses on parallel fibers through which they may form a pulse assembly. This notion is analogous to Hebb's concept of a cell assembly, but on a lower level of the neural hierarchy.

  19. Fat Grafting for Facial Filling and Regeneration.

    PubMed

    Coleman, Sydney R; Katzel, Evan B

    2015-07-01

    Plastic surgeons have come to realize that fat grafting can rejuvenate an aging face by restoring or creating fullness. However, fat grafting does much more than simply add volume. Grafted fat can transform or repair the tissues into which it is placed. Historically, surgeons have hesitated to embrace the rejuvenating potential of fat grafting because of poor graft take, fat necrosis, and inconsistent outcomes. This article describes fat grafting techniques and practices to assist readers in successful harvesting, processing, and placement of fat for optimal graft retention and facial esthetic outcomes. PMID:26116934

  20. Clinical Outcomes for Breast Cancer Patients Undergoing Mastectomy and Reconstruction with Use of DermACELL, a Sterile, Room Temperature Acellular Dermal Matrix

    PubMed Central

    Vashi, Christopher

    2014-01-01

    Background. Decellularized human skin has been used in a variety of medical applications, primarily involving soft tissue reconstruction, wound healing, and tendon augmentation. Theoretically, decellularization removes potentially immunogenic material and provides a clean scaffold for cellular and vascular in growth. The use of acellular dermal matrix in two-stage postmastectomy breast reconstruction is described. Methods. Ten consecutive breast cancer patients were treated with mastectomies and immediate reconstruction from August to November 2011. There were 8 bilateral and 1 unilateral mastectomies for a total of 17 breasts, with one exclusion for chronic tobacco use. Reconstruction included the use of a new 6 × 16 cm sterile, room temperature acellular dermal matrix patch (DermACELL) soaked in a cefazolin bath. Results. Of the 17 breasts, 15 reconstructions were completed; 14 of them with expander to implant sequence and acellular dermal matrix. Histological analysis of biopsies obtained during trimming of the matrix at the second stage appeared nonremarkable with evidence of normal healing, cellularity, and vascular infiltration. Conclusion. Postoperative observations showed that this cellular dermal matrix appears to be an appropriate adjunct to reconstruction with expanders. This acellular dermal matrix appeared to work well with all patients, even those receiving postoperative chemotherapy, postoperative radiation, prednisone, or warfarin sodium. PMID:24738030

  1. Bone Grafting the Cleft Maxilla

    MedlinePlus

    ... amount of bone from one place (usually the hip, head, ribs, or leg) and placing it in ... adjacent teeth into the bone graft; 2) prosthetic replacement (dental bridge); or 3) dental metallic bone implants. ...

  2. Reconstruction of a Severely Crushed Leg with Interpositional Vessel Grafts and Latissimus Dorsi Flap

    PubMed Central

    Park, Chan Woo; Hwang, Kyu Tae; Kim, Jeong Tae

    2012-01-01

    We present a case of a near total amputation at the distal tibial level, in which the patient emphatically wanted to save the leg. The anterior and posterior tibial nerves were intact, indicating a high possibility of sensory recovery after revascularization. The patient had open fractures at the tibia and fibula, but no bone shortening was performed. The posterior tibial vessels were reconstructed with an interposition saphenous vein graft from the contralateral side and a usable anterior tibial artery graft from the undamaged ipsilateral distal portions. The skin and soft tissue defects were covered using a subatmospheric pressure system for demarcating the wound, and a latissimus dorsi myocutaneous free flap for definite coverage of the wound. At 6 months after surgery, the patient was ambulatory without requiring additional procedures. Replantation without bone shortening, with use of vessel grafts and temporary coverage of the wound with subatmospheric pressure dressings before definite coverage, can shorten recovery time. PMID:22872848

  3. Experience of injected fat grafting.

    PubMed

    Matsudo, P K; Toledo, L S

    1988-02-01

    Eighteen months' experience with the injected fat grafting technique used in 208 patients to correct various problems such as buttocks (augmentation and reshaping), trochanteric depressions, breast augmentation, scar depressions, thighs and legs (calf and ankle augmentation), small wrinkles and depressions of the face (Romberg's disease), nasolabial fold, upper outer breast quadrant, liposuction sequela, fingers and hands is presented. This method shows major advantages with few complications. Some technical details and recommendations for successful fat grafting are also presented. PMID:3376783

  4. Fibrin glue repair leads to enhanced axonal elongation during early peripheral nerve regeneration in an in vivo mouse model

    PubMed Central

    Koulaxouzidis, Georgios; Reim, Gernot; Witzel, Christian

    2015-01-01

    Microsurgical suturing is the gold standard of nerve coaptation. Although literature on the usefulness of fibrin glue as an alternative is becoming increasingly available, it remains contradictory. Furthermore, no data exist on how both repair methods might influence the morphological aspects (arborization; branching) of early peripheral nerve regeneration. We used the sciatic nerve transplantation model in thy-1 yellow fluorescent protein mice (YFP; n = 10). Pieces of nerve (1cm) were grafted from YFP-negative mice (n = 10) into those expressing YFP. We performed microsuture coaptations on one side and used fibrin glue for repair on the contralateral side. Seven days after grafting, the regeneration distance, the percentage of regenerating and arborizing axons, the number of branches per axon, the coaptation failure rate, the gap size at the repair site and the time needed for surgical repair were all investigated. Fibrin glue repair resulted in regenerating axons travelling further into the distal nerve. It also increased the percentage of arborizing axons. No coaptation failure was detected. Gap sizes were comparable in both groups. Fibrin glue significantly reduced surgical repair time. The increase in regeneration distance, even after the short period of time, is in line with the results of others that showed faster axonal regeneration after fibrin glue repair. The increase in arborizing axons could be another explanation for better functional and electrophysiological results after fibrin glue repair. Fibrin glue nerve coaptation seems to be a promising alternative to microsuture repair. PMID:26330844

  5. Robot-assisted C7 nerve root transfer from the contralateral healthy side: A preliminary cadaver study.

    PubMed

    Jiang, Su; Ichihara, Satoshi; Prunières, Guillaume; Peterson, Brett; Facca, Sybille; Xu, Wen-Dong; Liverneaux, Philippe

    2016-04-01

    Patients with cerebral palsy and spastic hemiplegia may have extremely poor upper extremity function. Unfortunately, many current therapies and treatments for patients with spastic hemiplegia offer very limited improvements. One innovative technique for treating these patients is the use a contralateral C7 nerve root transfer to neurotize the C7 nerve root in the affected limb. This may result not only in less spasticity in the affected limb, but also improved control and motor function vis-a-vis the new connection to the normal cerebral hemisphere. However, contralateral C7 transfers can require large incisions and long nerve grafts. The aim of this study was to test the feasibility of a contralateral C7 nerve root transfer procedure with the use of a prevertebral minimally invasive robot-assisted technique. In a cadaver, both sides of the C7 root were dissected. The right recipient C7 root was resected as proximally as possible, while the left donor C7 root was resected as distally as possible. With the use of the da Vinci (®) SI surgical robot (Intuitive Surgical ™, Sunnyvale, CA, USA), we were able to eliminate the large incision and use a much shorter nerve graft when performing contralateral C7 nerve transfer. PMID:27117122

  6. Interventions in Infrainguinal Bypass Grafts

    SciTech Connect

    Mueller-Huelsbeck, S. Order, B.-M.; Jahnke, T.

    2006-02-15

    The interventional radiologist plays an important role in the detection and prevention of infrainguinal bypass failure. Early detection and evaluation of flow-limiting lesions effectively preserve graft (venous bypass and polyester or expanded polytetrafluoroethylene bypass) patency by identifying stenoses before occlusion occurs. Delay in treatment of the at-risk graft may result in graft failure and a reduced chance of successful revascularization. For this reason, surveillance protocols form an important part of follow-up after infrainguinal bypass surgery. As well as having an understanding of the application of imaging techniques including ultrasound, MR angiography, CT angiography and digital subtraction angiography, the interventional radiologist should have detailed knowledge of the minimally invasive therapeutic options. Percutaneous transluminal angioplasty (PTA), or alternatively cutting balloon angioplasty, is the interventional treatment of choice in prevention of graft failure and occlusion. Further alternatives include metallic stent placement, fibrinolysis, and mechanical thrombectomy. Primary assisted patency rates following PTA can be up to 65% at 5 years. When the endovascular approach is unsuccessful, these therapeutic options are complemented by surgical procedures including vein patch revision, jump grafting, or placement of a new graft.

  7. Costal Grafting in Mandibular Reconstruction

    PubMed Central

    Bourlet, Jerôme; Château, Joseph; Jacquemart, Mathieu; Dufour, Clémence; Mojallal, Ali; Gleizal, Arnaud

    2015-01-01

    Background: Reconstruction of mandibular bone defect is a common indication in craniomaxillofacial surgery, and free fibular flap is the gold standard for this indication. However, there are alternatives; nonvascular bone grafting is one of them, and we present the costal grafting for mandibular reconstruction, a classic technique that is reliable, efficient, and produced less morbidity than the technique of using composite free flaps. Method: A 9-year retrospective review of 54 patients treated surgically for mandibular reconstruction was performed. The criterion mainly analyzed was graft survival. The surgical technique was described in detail. Results: A total of 54 patients with mandibular bone defect were identified. Five symphysis, 46 corpus, and 20 ramus defects were considered. These patients underwent reconstruction by costal grafting, and the engrafting was successful in 92.6% of cases. Dental rehabilitation with dental implants was realized in 70% of cases. Conclusions: The approach described in this article allowed the authors to obtain good results with costal grafting for mandibular reconstruction and dental rehabilitation. Costal grafting is a good alternative for fibula free flap in specific indications. Reconstruction of mandibular bone defect is a common indication in craniomaxillofacial surgery. Since the 1980s, the gold standard for these defects is the use of free fibular flap.1 In some cases, this technique is contradicted; the surgeon then has several possibilities for the use of free osteomyocutaneous flaps (iliac crest, scapula, and serrato-costal flaps).2–8 PMID:26893990

  8. Bilateral internal thoracic artery grafting

    PubMed Central

    2013-01-01

    The effectiveness of the left internal mammary artery graft to the anterior descending coronary artery as a surgical strategy has been shown to improve the survival rate and decrease the risk of adverse cardiac events in patients undergoing coronary bypass surgery. These clinical benefits appear to be related to the superior short and long-term patency rates of the internal thoracic artery graft. Although the advantages of using of both internal thoracic arteries (ITA) for bypass grafting have taken longer to prove, recent results from multiple data sets now support these findings. The major advantage of bilateral ITA grafting appears to be improved survival rate, while the disadvantages of complex ITA grafting include the increased complexity of operation, and an increased risk of wound complications. While these short-term disadvantages have been mitigated in contemporary surgical practice, they have not eliminated. Bilateral ITA grafting should be considered the procedure of choice for patients undergoing coronary bypass surgery that have a predicted survival rate of longer than ten years. PMID:23977627

  9. Ultrasound-Guided Peripheral Nerve Procedures.

    PubMed

    Strakowski, Jeffrey A

    2016-08-01

    Ultrasound guidance allows real-time visualization of the needle in peripheral nerve procedures, improving accuracy and safety. Sonographic visualization of the peripheral nerve and surrounding anatomy can provide valuable information for diagnostic purposes and procedure enhancement. Common procedures discussed are the suprascapular nerve at the suprascapular notch, deep branch of the radial nerve at the supinator, median nerve at the pronator teres and carpal tunnel, lateral cutaneous nerve of the thigh, superficial fibular nerve at the leg, tibial nerve at the ankle, and interdigital neuroma. For each procedure, the indications, relevant anatomy, preprocedural scanning technique, and injection procedure itself are detailed. PMID:27468673

  10. In vivo characterization of regenerative peripheral nerve interface function

    NASA Astrophysics Data System (ADS)

    Ursu, Daniel C.; Urbanchek, Melanie G.; Nedic, Andrej; Cederna, Paul S.; Gillespie, R. Brent

    2016-04-01

    Objective. Regenerative peripheral nerve interfaces (RPNIs) are neurotized free autologous muscle grafts equipped with electrodes to record myoelectric signals for prosthesis control. Viability of rat RPNI constructs have been demonstrated using evoked responses. In vivo RPNI characterization is the next critical step for assessment as a control modality for prosthetic devices. Approach. Two RPNIs were created in each of two rats by grafting portions of free muscle to the ends of divided peripheral nerves (peroneal in the left and tibial in the right hind limb) and placing bipolar electrodes on the graft surface. After four months, we examined in vivo electromyographic signal activity and compared these signals to muscular electromyographic signals recorded from autologous muscles in two rats serving as controls. An additional group of two rats in which the autologous muscles were denervated served to quantify cross-talk in the electrode recordings. Recordings were made while rats walked on a treadmill and a motion capture system tracked the hind limbs. Amplitude and periodicity of signals relative to gait were quantified, correlation between electromyographic and motion recording were assessed, and a decoder was trained to predict joint motion. Main Results. Raw RPNI signals were active during walking, with amplitudes of 1 mVPP, and quiet during standing, with amplitudes less than 0.1 mVPP. RPNI signals were periodic and entrained with gait. A decoder predicted bilateral ankle motion with greater than 80% reliability. Control group signal activity agreed with literature. Denervated group signals remained quiescent throughout all evaluations. Significance. In vivo myoelectric RPNI activity encodes neural activation patterns associated with gait. Signal contamination from muscles adjacent to the RPNI is minimal, as demonstrated by the low amplitude signals obtained from the Denervated group. The periodicity and entrainment to gait of RPNI recordings suggests the

  11. Anatomic study of the superficial sural artery and its implication in the neurocutaneous vascularized sural nerve free flap.

    PubMed

    Leclère, Franck Marie; Eggli, Simone; Mathys, Lukas; Vögelin, Esther

    2013-10-01

    Combined extended nerve and soft tissue defects of the upper extremity require nerve reconstruction and adequate soft tissue coverage. This study focuses on the reliability of the free vascularized sural nerve graft combined with a fasciocutaneous posterior calf flap within this indication. An anatomical study was performed on 26 cadaveric lower extremities that had been Thiel fixated and color silicone injected. Dissection of the fasciocutaneous posterior calf flap involved the medial sural nerve and superficial sural artery (SSA) with its septocutaneous perforators, extended laterally to include the lateral cutaneous branch of the sural nerve and continued to the popliteal origin of the vascular pedicle and the nerves. The vessel and nerves diameter were measured with an eyepiece reticle at 4.5× magnification. Length and diameter of the nerves and vessels were carefully assessed and reported in the dissection book. A total of 26 flaps were dissected. The SSA originated from the medial sural artery (13 cases), the popliteal artery (12 cases), or the lateral sural artery (one case). The average size of the SSA was 1.4 ± 0.4 mm. The mean pedicle length before the artery joined the sural nerve was 4.5 ± 1.9 cm. A comitant vein was present in 21 cases with an average diameter of 2.0 ± 0.8 mm, in 5 cases a separate vein needed to be dissected with an average diameter of 3.5 ± 0.4 mm. The mean medial vascularized sural nerve length was 21.2 ± 8.9 cm. Because of inclusion of the vascularized part of the lateral branch of the sural nerve (mean length of 16.7 ± 4.8 cm), a total of 35.0 ± 9.6 cm mean length of vascularized nerve could be gained from each extremity. The free vascularized sural nerve graft combined with a fasciocutaneous posterior calf flap pedicled on the SSA offers a reliable solution for complex tissue and nerve defect. PMID:22467447

  12. Covalent immobilization of stem cell inducing/recruiting factor and heparin on cell-free small-diameter vascular graft for accelerated in situ tissue regeneration.

    PubMed

    Shafiq, Muhammad; Jung, Youngmee; Kim, Soo Hyun

    2016-06-01

    The development of cell-free vascular grafts has tremendous potential for tissue engineering. However, thrombus formation, less-than-ideal cell infiltration, and a lack of growth potential limit the application of electrospun scaffolds for in situ tissue-engineered vasculature. To overcome these challenges, here we present development of an acellular tissue-engineered vessel based on electrospun poly(L-lactide-co-ɛ-caprolactone) scaffolds. Heparin was conjugated to suppress thrombogenic responses, and substance P (SP) was immobilized to recruit host cells. SP was released in a sustained manner from scaffolds and recruited human bone marrow-derived mesenchymal stem cells. The biocompatibility and biological performance of the grafts were evaluated by in vivo experiments involving subcutaneous scaffold implantation in Sprague-Dawley rats (n = 12) for up to 4 weeks. Histological analysis revealed a higher extent of accumulative host cell infiltration, neotissue formation, collagen deposition, and elastin deposition in scaffolds containing either SP or heparin/SP than in the control groups. We also observed the presence of a large number of laminin-positive blood vessels, von Willebrand factor (vWF(+) ) cells, and alpha smooth muscle actin-positive cells in the explants containing SP and heparin/SP. Additionally, SP and heparin/SP grafts showed the existence of CD90(+) and CD105(+) MSCs and induced a large number of M2 macrophages to infiltrate the graft wall compared with that observed with the control group. Our cell-free grafts could enhance vascular regeneration by endogenous cell recruitment and by mediating macrophage polarization into the M2 phenotype, suggesting that these constructs may be a promising cell-free graft candidate and are worthy of further in vivo evaluation. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1352-1371, 2016. PMID:26822178

  13. Primary Graft Dysfunction

    PubMed Central

    Christie, Jason D

    2014-01-01

    Primary graft dysfunction (PGD) is a syndrome encompassing a spectrum of mild to severe lung injury that occurs within the first 72 hours after lung transplantation. PGD is characterized by pulmonary edema with diffuse alveolar damage that manifests clinically as progressive hypoxemia with radiographic pulmonary infiltrates. In recent years, new knowledge has been generated on risks and mechanisms of PGD. Following ischemia and reperfusion, inflammatory and immunological injury-repair responses appear to be key controlling mechanisms. In addition, PGD has significant impact on short- and long-term outcomes; therefore, the choice of donor organ is impacted by this potential adverse consequence. Improved methods of reducing PGD risk and efforts to safely expand the pool are being developed. Ex-vivo lung perfusion is a strategy which may improve risk assessment and become a promising platform to implement treatment interventions to prevent PGD. This review will detail recent updates in the epidemiology, pathophysiology, molecular and genetic biomarkers and state-of-the-art technical developments affecting PGD. (158 words) PMID:23821506

  14. Exposure to Nerve Growth Factor Worsens Nephrotoxic Effect Induced by Cyclosporine A in HK-2 Cells

    PubMed Central

    Lofaro, Danilo; Toteda, Giuseppina; Lupinacci, Simona; Leone, Francesca; Gigliotti, Paolo; Papalia, Teresa; Bonofiglio, Renzo

    2013-01-01

    Nerve growth factor is a neurotrophin that promotes cell growth, differentiation, survival and death through two different receptors: TrkANTR and p75NTR. Nerve growth factor serum concentrations increase during many inflammatory and autoimmune diseases, glomerulonephritis, chronic kidney disease, end-stage renal disease and, particularly, in renal transplant. Considering that nerve growth factor exerts beneficial effects in the treatment of major central and peripheral neurodegenerative diseases, skin and corneal ulcers, we asked whether nerve growth factor could also exert a role in Cyclosporine A-induced graft nephrotoxicity. Our hypothesis was raised from basic evidence indicating that Cyclosporine A-inhibition of calcineurin-NFAT pathway increases nerve growth factor expression levels. Therefore, we investigated the involvement of nerve growth factor and its receptors in the damage exerted by Cyclosporine A in tubular renal cells, HK-2. Our results showed that in HK-2 cells combined treatment with Cyclosporine A + nerve growth factor induced a significant reduction in cell vitality concomitant with a down-regulation of Cyclin D1 and up-regulation of p21 levels respect to cells treated with Cyclosporine A alone. Moreover functional experiments showed that the co-treatment significantly up-regulated human p21promoter activity by involvement of the Sp1 transcription factor, whose nuclear content was negatively regulated by activated NFATc1. In addition we observed that the combined exposure to Cyclosporine A + nerve growth factor promoted an up-regulation of p75 NTR and its target genes, p53 and BAD leading to the activation of intrinsic apoptosis. Finally, the chemical inhibition of p75NTR down-regulated the intrinsic apoptotic signal. We describe two new mechanisms by which nerve growth factor promotes growth arrest and apoptosis in tubular renal cells exposed to Cyclosporine A. PMID:24244623

  15. Occipital nerve stimulation.

    PubMed

    Mammis, Antonios; Agarwal, Nitin; Mogilner, Alon Y

    2015-01-01

    Occipital nerve stimulation (ONS) is a form of neuromodulation therapy aimed at treating intractable headache and craniofacial pain. The therapy utilizes neurostimulating electrodes placed subcutaneously in the occipital region and connected to a permanently implanted programmable pulse generator identical to those used for dorsal column/spinal cord stimulation. The presumed mechanisms of action involve modulation of the trigeminocervical complex, as well as closure of the physiologic pain gate. ONS is a reversible, nondestructive therapy, which can be tailored to a patient's individual needs. Typically, candidates for successful ONS include those patients with migraines, Chiari malformation, or occipital neuralgia. However, recent MRSA infections, unrealistic expectations, and psychiatric comorbidities are generally contraindications. As with any invasive procedure, complications may occur including lead migration, infection, wound erosion, device failure, muscle spasms, and pain. The success of this therapy is dependent on careful patient selection, a preimplantation trial, meticulous implantation technique, programming strategies, and complication avoidance. PMID:25411143

  16. A spun elastomeric graft for dialysis access.

    PubMed

    Drasler, W J; Wilson, G J; Stenoien, M D; Jenson, M L; George, S A; Dutcher, R G; Possis, Z C

    1993-01-01

    A new composite vascular graft was developed using electrostatic spinning technology. The graft is primarily microfibrous polydimethylsiloxane spun onto a mandrel; a small diameter polyester yarn provides additional strength while minimizing wall thickness, and a helical bead provides crush and kink resistance. Eighteen grafts were implanted in a mongrel canine arteriovenous shunt model for 12 months. The grafts were implanted in femoral artery to femoral vein loops and were cannulated using three pairs of 16 gauge dialysis needles per week. Grafts were evaluated during each puncture session, and also followed using angiography. Histologic study of explanted grafts, regional lymph nodes, and lungs was performed. The grafts provided excellent handling and puncture characteristics, with no bleeding through the graft wall at puncture sites. Cumulative patency of these punctured grafts was 88% at 6 months and 80% at 1 year. Histologic study showed external fibroconnective tissue encapsulation of the grafts, with tissue growth through the interstices of the graft consisting of a microvascular network surrounded predominantly by histiocytes, many multinucleated foreign body giant cells, with some fibroblasts and collagen formation also present. Little luminal thrombus was seen at puncture sites in the patent grafts, and there was no evidence of pulmonary thromboemboli. This new elastomeric graft shows excellent promise for dialysis access; similar grafts under development may also find application for small diameter peripheral vascular reconstruction. PMID:8324257

  17. Methods to evaluate functional nerve recovery in adult rats: walking track analysis, video analysis and the withdrawal reflex.

    PubMed

    Dijkstra, J R; Meek, M F; Robinson, P H; Gramsbergen, A

    2000-03-15

    The aim of this study was to compare different methods for the evaluation of functional nerve recovery. Three groups of adult male Wistar rats were studied. In group A, a 12-mm gap between nerve ends was bridged by an autologous nerve graft; in rats of group B we performed a crush lesion of the sciatic nerve and group C consisted of non-operated control rats. The withdrawal reflex, elicited by an electric stimulus, was used to evaluate the recovery of sensory nerve function. To investigate motor nerve recovery we analyzed the walking pattern. Three different methods were used to obtain data for footprint analysis: photographic paper with thickened film developer on the paws, normal white paper with finger paint, and video recordings. The footprints were used to calculate the sciatic function index (SFI). From the video recordings, we also analyzed stepcycles. The withdrawal reflex is a convenient and reproducible test for the evaluation of global sensory nerve recovery. Recording walking movements on video and the analysis of footplacing is a perfect although time-consuming method for the evaluation of functional aspects of motor nerve recovery. PMID:10720672

  18. The cell mediated and humoral immune response to vaccination with acellular and whole cell pertussis vaccine in adult humans.

    PubMed

    Petersen, J W; Ibsen, P H; Bentzon, M W; Capiau, C; Heron, I

    1991-10-01

    The cell mediated immune response (CMI) against pertussis antigens following vaccination with the traditional Danish whole cell pertussis vaccine (WC-P) and the Japanese acellular pertussis vaccine (A-PV) JNIH-3 was studied in four adult human volunteers. Vaccination with the A-PV induced an in vitro proliferative response of peripheral blood lymphocytes to pertussis toxin (PT) subunits S2-S4, S3-S4 and S5 and the filamentous hemagglutinin (FHA), and a better serological response to native PT, detoxified PT (dPT) and FHA than the WC-PV. The induced CMI and serological response were followed over a period of 17 weeks, and were not seen to decline during this period. Further, an in vitro proliferative response to Bordetella pertussis agglutinogen 2 and 3 were demonstrated using lymphocytes from recently and not-so-recently pertussis-vaccinated adults. PMID:1797049

  19. Articulating external fixation to overcome nerve gaps in lower extremity trauma.

    PubMed

    Ruch, David S; Smith, Adam M

    2003-04-01

    This report describes the use of articulating external fixation in patients with lower extremity trauma with segmental nerve defects. Four patients who would otherwise require nerve grafting underwent application of an articulated external fixator, allowing optimal positioning for end-to-end, tension-free nerve repair followed by gradual lengthening. After three weeks of immobilization, the fixator was gradually advanced through the arc of the hinge. At an average follow-up of 44 months, motor function testing revealed gastroc-soleus function in all cases with a median motor grade of M4. Sensory function testing with Semmes-Weinstein monofilaments demonstrated protective plantar sensation in all cases with a median monofilament size of 3.84 on the injured limb compared with 3.22 on the contralateral side. This series of patients demonstrates that joint positioning through external fixation may be used safely and effectively to facilitate primary neurorrhaphy and subsequent limb salvage. PMID:12679690

  20. Ultrasound-guided Pulsed Radiofrequency Lesioning of the Phrenic Nerve in a Patient with Intractable Hiccup

    PubMed Central

    Kang, Keum Nae; Park, In Kyung; Suh, Jeong Hun; Leem, Jeong Gill

    2010-01-01

    Persistent and intractable hiccups (with respective durations of more than 48 hours and 1 month) can result in depression, fatigue, impaired sleep, dehydration, weight loss, malnutrition, and aspiration syndromes. The conventional treatments for hiccups are either non-pharmacological, pharmacological or a nerve block treatment. Pulsed radiofrequency lesioning (PRFL) has been proposed for the modulation of the excited nervous system pathway of pain as a safe and nondestructive treatment method. As placement of the electrode in close proximity to the targeted nerve is very important for the success of PRFL, ultrasound appears to be well suited for this technique. A 74-year-old man suffering from intractable hiccups that had developed after a coronary artery bypass graft and had continued for 7 years was referred to our pain clinic. He had not been treated with conventional methods or medications. We performed PRFL of the phrenic nerve guided by ultrasound and the hiccups disappeared. PMID:20830266

  1. Developments at the graft interface in homo- and hetero-grafts

    PubMed Central

    Clemente Moreno, Maria José; Hevin, Cyril; Ollat, Nathalie; Cookson, Sarah Jane

    2014-01-01

    Gene expression changes induced during graft union formation (the first month after grafting) in grapevine have been studied using whole genome microarrays. The genes differentially expressed between the rootstock and graft interface tissues of homo-grafts (Cabernet Sauvignon (CS) grafted onto CS) were compared at 3 and 28 days after grafting (dag). Graft union formation was associated with the upregulation of genes involved in secondary metabolism, cell wall, wound responses and hormone signaling. These gene expression differences were associated with the accumulation of lignin, cellulose and callose in the callus cells. Superimposed upon this, hetero-grafting between two different grapevine genotypes resulted in the further upregulation of stress and/or defense responses at the graft interface. Here we discuss the limitations of the techniques used to study the developments at the graft interface to date and future research directions to understand graft union formation in plants. PMID:24770337

  2. Acellular porcine corneal matrix as a carrier scaffold for cultivating human corneal epithelial cells and fibroblasts in vitro

    PubMed Central

    Zhang, Ju; Zhang, Can-Wei; Du, Li-Qun; Wu, Xin-Yi

    2016-01-01

    AIM To investigate the feasibility of corneal anterior lamellar reconstruction with human corneal epithelial cells and fibroblasts, and an acellular porcine cornea matrix (APCM) in vitro. METHODS The scaffold was prepared from fresh porcine corneas which were treated with 0.5% sodium dodecyl sulfate (SDS) solution and the complete removal of corneal cells was confirmed by hematoxylin-eosin (HE) staining and 4′, 6-diamidino-2-phenylindole (DAPI) staining. Human corneal fibroblasts and epithelial cells were cultured with leaching liquid extracted from APCM, and then cell proliferative ability was evaluated by MTT assay. To construct a human corneal anterior lamellar replacement, corneal fibroblasts were injected into the APCM and cultured for 3d, followed by culturing corneal epithelial cells on the stroma construction surface for another 10d. The corneal replacement was analyzed by HE staining, and immunofluorescence staining. RESULTS Histological examination indicated that there were no cells in the APCM by HE staining, and DAPI staining did not detect any residual DNA. The leaching liquid from APCM had little influence on the proliferation ability of human corneal fibroblasts and epithelial cells. At 10d, a continuous 3 to 5 layers of human corneal epithelial cells covering the surface of the APCM was observed, and the injected corneal fibroblasts distributed within the scaffold. The phenotype of the construction was similar to normal human corneas, with high expression of cytokeratin 12 in the epithelial cell layer and high expression of vimentin in the stroma. CONCLUSION Corneal anterior lamellar replacement can be reconstructed in vitro by cultivating human corneal epithelial cells and fibroblasts with an acellular porcine cornea matrix. This laid the foundation for the further transplantation in vivo. PMID:26949602

  3. Malignant Peripheral Nerve Sheath Tumor.

    PubMed

    James, Aaron W; Shurell, Elizabeth; Singh, Arun; Dry, Sarah M; Eilber, Fritz C

    2016-10-01

    Malignant peripheral nerve sheath tumor (MPNST) is the sixth most common type of soft tissue sarcoma. Most MPNSTs arise in association with a peripheral nerve or preexisting neurofibroma. Neurofibromatosis type is the most important risk factor for MPNST. Tumor size and fludeoxyglucose F 18 avidity are among the most helpful parameters to distinguish MPNST from a benign peripheral nerve sheath tumor. The histopathologic diagnosis is predominantly a diagnosis of light microscopy. Immunohistochemical stains are most helpful to distinguish high-grade MPNST from its histologic mimics. Current surgical management of high-grade MPNST is similar to that of other high-grade soft tissue sarcomas. PMID:27591499

  4. Saphenous vein forearm grafts and gortex thigh grafts as alternative forms of vascular access.

    PubMed

    Bhandari, S; Wilkinson, A; Sellars, L

    1995-11-01

    To compare the survival and complication rates of saphenous vein forearm grafts and gortex thigh grafts. Retrospective study over a twelve-year period with review of case-notes. Saphenous vein forearm grafts were constructed in 17 males and 12 females, mean age 61 years and gortex thigh grafts in 24 males and 22 females (49 grafts), mean age 49 years. Grafts were the primary form of access in 9 patients in each group. Follow-up was 45.6 and 135.2 patient years on dialysis for forearm grafts and thigh grafts respectively. One-year total survival was 89.4% (89.4% at 2 years and 71.5% at 3 years) and 84.9% (82.3% at 2 years and 70.4% at 3 years) for saphenous vein forearm grafts and gortex thigh grafts respectively. The overall complication rates were 0.22 and 0.61 per patient year on dialysis for saphenous vein forearm grafts and gortex thigh grafts respectively. Thrombosis occurred in 10% and 52%, infection in 0% and 35% and no complications in 62% and 24% of saphenous vein forearm grafts and gortex thigh grafts respectively. Both saphenous vein forearm grafts and gortex thigh grafts can provide satisfactory vascular access. The survival is similar at one year but gortex thigh grafts have a higher complication rate. PMID:8605714

  5. 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

  6. Graft Diameter matters in Hamstring ACL reconstruction

    PubMed Central

    Clatworthy, Mark

    2016-01-01

    Objective: Recently techniques have been developed to increase graft diameter in hamstring ACL reconstruction with the hope to decrease graft failure. To date there is limited evidence to show that a smaller graft diameter results in a higher ACL failure rate. Method: The factors for failure in 1480 consecutive single surgeon hamstring ACL reconstructions were evaluated prospectively. Patients were followed for 2-15 years. A multivariate analysis was performed which looked at graft size, age, sex, time to surgery, meniscal integrity, meniscal repair and ACL graft placement to determine whether graft diameter matters in determining the failure of hamstring ACL reconstruction. Results: Graft diameters ranged from 6-10 mm. The mean graft diameter for all patients was 7.75 mm. 83 ACL reconstructions failed. The mean size of graft failures was 7.55 mm ACL reconstructions that failed had a significantly smaller hamstring graft diameter p=0.001. The Hazard Ratio for a smaller diameter graft is 0.517 p=<0.0001. For every 1 mm decrease in graft diameter there is a 48.3% higher chance of failure. The multivariate analysis showed a hazard ratio of 0.543 p=0.002. For every 1 mm decrease in graft diameter there is a 45.7% higher chance of failure. Conclusion: Smaller diameter hamstring grafts do have a higher failure rate. Grafts ≤ 7.5 mm had twice the failure rate of grafts ≥8 mm using a multivariate analysis for every 1 mm decrease in graft diameter there is a 45.7% higher chance of failure.

  7. 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

  8. Nerve Disease and Bladder Control

    MedlinePlus

    ... Research Training & Career Development Grant programs for students, postdocs, and faculty Research at NIDDK Labs, faculty, and ... KB) Alternate Language URL Nerve Disease and Bladder Control Page Content On this page: What bladder control ...

  9. Ion Channels in Nerve Membranes

    ERIC Educational Resources Information Center

    Ehrenstein, Gerald

    1976-01-01

    Discusses research that indicates that nerve membranes, which play a key role in the conduction of impulses, are traversed by protein channels with ion pathways opened and closed by the membrane electric field. (Author/MLH)

  10. Imaging of the facial nerve.

    PubMed

    Veillona, F; Ramos-Taboada, L; Abu-Eid, M; Charpiot, A; Riehm, S

    2010-05-01

    The facial nerve is responsible for the motor innervation of the face. It has a visceral motor function (lacrimal, submandibular, sublingual glands and secretion of the nose); it conveys a great part of the taste fibers, participates to the general sensory of the auricle (skin of the concha) and the wall of the external auditory meatus. The facial mimic, production of tears, nasal flow and salivation all depend on the facial nerve. In order to image the facial nerve it is mandatory to be knowledgeable about its normal anatomy including the course of its efferent and afferent fibers and about relevant technical considerations regarding CT and MR to be able to achieve high-resolution images of the nerve. PMID:20456888

  11. POST CORONARY ARTERY BYPASS GRAFT STUDY (CABG)

    EPA Science Inventory

    Relative effectiveness of moderate versus more aggressive lipid lowering, and of low dose anticoagulation versus placebo, in delaying saphenous vein coronary bypass graft atherosclerosis and preventing occlusion of saphenous grafts of patients with saphenous vein coronary bypass ...

  12. Hemangioma of the Facial Nerve

    PubMed Central

    Balkany, Thomas; Fradis, Milo; Jafek, Bruce W.; Rucker, Nolan C.

    1991-01-01

    Hemangioma of the facial nerve may occur more frequently than previously recognized. This benign vascular tumor most often arises in the area of the geniculate ganglion, although the reason for this site of predilection is not known. Using silicon injection and cross-sectional vessel counts, we recently demonstrated the presence of a geniculate capillary plexus (GCP) in the cat. The present study was designed to identify a similar GCP in man, if present, and to relate if to the site of predilection of hemangioma of the facial nerve. Twenty-five human facial nerves were studied in horizontally sectioned temporal bones. A clinical case of hemangioma arising at the geniculate ganglion is presented. The human geniculate ganglion has a very rich capillary plexus in contrast to the poor intrinsic vasculature of the adjacent labyrinthine segment and nioderate vasculature of the tympanic segment of the facial nerve. We hypothesize that the GCP is the origin of most hemangiomas of facial nerve. The anatomic distinctness of the geniculate gangion and GCP from the facial nerve may allow removal of these tumors with preservation of motor function in certain cases. ImagesFigure 1Figure 2Figure 3 PMID:17170823

  13. [Peripheral Nerve Injuries in Sports].

    PubMed

    Tettenborn, B; Mehnert, S; Reuter, I

    2016-09-01

    Peripheral nerve injuries due to sports are relatively rare but the exact incidence is not known due to a lack of epidemiological studies. Particular sports activities tend to cause certain peripheral nerve injuries including direct acute compression or stretching, repetitive compression and stretching over time, or another mechanism such as ischemia or laceration. These nerve lesions may be severe and delay or preclude the athlete's return to sports, especially in cases with delayed diagnosis. Repetitive and vigorous use or overuse makes the athlete vulnerable to disorders of the peripheral nerves, and sports equipment may cause compression of the nerves. Depending on etiology, the treatment is primarily conservative and includes physiotherapy, modification of movements and sports equipment, shoe inserts, splinting, antiphlogistic drugs, sometimes local administration of glucocorticoids or, lately, the use of extracorporeal shock waves. Most often, cessation of the offending physical activity is necessary. Surgery is only indicated in the rare cases of direct traumatic nerve injury or when symptoms are refractory to conservative therapy. Prognosis mainly depends on the etiology and the available options of modifying measures.This article is based on the publications "Reuter I, Mehnert S. Engpasssyndrome peripherer Nerven bei Sportlern". Akt Neurol 2012;39:292-308 and Sportverl Sportschad 2013;27:130-146. PMID:27607069

  14. Allotransplanted Neurons Used to Repair Peripheral Nerve Injury Do Not Elicit Overt Immunogenicity

    PubMed Central

    Liu, Weimin; Ren, Yi; Bossert, Adam; Wang, Xiaowei; Dayawansa, Samantha; Tong, Jing; He, Xiaoshen; Smith, Douglas H.; Gelbard, Harris A.; Huang, Jason H.

    2012-01-01

    A major problem hindering the development of autograft alternatives for repairing peripheral nerve injuries is immunogenicity. We have previously shown successful regeneration in transected rat sciatic nerves using conduits filled with allogeneic dorsal root ganglion (DRG) cells without any immunosuppression. In this study, we re-examined the immunogenicity of our DRG neuron implanted conduits as a potential strategy to overcome transplant rejection. A biodegradable NeuraGen® tube was infused with pure DRG neurons or Schwann cells cultured from a rat strain differing from the host rats and used to repair 8 mm gaps in the sciatic nerve. We observed enhanced regeneration with allogeneic cells compared to empty conduits 16 weeks post-surgery, but morphological analyses suggest recovery comparable to the healthy nerves was not achieved. The degree of regeneration was indistinguishable between DRG and Schwann cell allografts although immunogenicity assessments revealed substantially increased presence of Interferon gamma (IFN-γ) in Schwann cell allografts compared to the DRG allografts by two weeks post-surgery. Macrophage infiltration of the regenerated nerve graft in the DRG group 16 weeks post-surgery was below the level of the empty conduit (0.56 fold change from NG; p<0.05) while the Schwann cell group revealed significantly higher counts (1.29 fold change from NG; p<0.001). Major histocompatibility complex I (MHC I) molecules were present in significantly increased levels in the DRG and Schwann cell allograft groups compared to the hollow NG conduit and the Sham healthy nerve. Our results confirmed previous studies that have reported Schwann cells as being immunogenic, likely due to MHC I expression. Nerve gap injuries are difficult to repair; our data suggest that DRG neurons are superior medium to implant inside conduit tubes due to reduced immunogenicity and represent a potential treatment strategy that could be preferable to the current gold standard of

  15. Primary Breast Augmentation with Fat Grafting.

    PubMed

    Coleman, Sydney R; Saboeiro, Alesia P

    2015-07-01

    The controversy over fat grafting to the breasts has now been settled. In 2009, the American Society of Plastic Surgeons Fat Graft Task Force stated that "Fat grafting may be considered for breast augmentation and correction of defects associated with medical conditions and previous breast surgeries; however, results are dependent on technique and surgeon expertise." This article discusses the history, indications, planning, complications, and present technique of fat grafting to the breast using the Coleman technique. PMID:26116935

  16. Organosiloxane-grafted natural polymer coatings

    DOEpatents

    Sugama, Toshifumi

    1998-01-01

    A new family of polysaccharide graft polymers are provided as corrosion resistant coatings having antimicrobial properties which are useful on light metals such as aluminum, magnesium, zinc, steel and their alloys. Methods of making the polysaccharide graft polymers are also included. The methods of making the polysaccharide graft polymers involve reacting a polysaccharide source with an antimicrobial agent under conditions of hydrolysis-condensation.

  17. Electrophysiological evaluation of nerve function in inferior alveolar nerve injury: relationship between nerve action potentials and histomorphometric observations.

    PubMed

    Murayama, M; Sasaki, K; Shibahara, T

    2015-12-01

    The objective of this study was to improve the accuracy of diagnosis of inferior alveolar nerve (IAN) injury by determining degrees of nerve disturbance using the sensory nerve action potential (SNAP) and sensory nerve conduction velocity (SCV). Crush and partial and complete nerve amputation injuries were applied to the IAN of rabbits, then SNAPs and histomorphometric observations were recorded at 1, 5, and 10 weeks. For crush injury, most nerves were smaller in diameter at 5 weeks than at 1 week, however after 10 weeks, extensive nerve regeneration was observed. The SNAP showed a decrease in SCV at weeks 1 and 5, followed by an increase at week 10. For partial nerve amputation, small to medium-sized nerve fibres were observed at weeks 1 and 5, then larger nerves were seen at week 10. Minimal changes in SCV were observed at weeks 1 and 5, however SCV increased at week 10. For complete nerve amputation, nerve fibres were sparse at week 1, but gradual nerve regeneration was observed at weeks 5 and 10. SNAPs were detectable from week 10, however the SCV was extremely low. This study showed SCV to be an effective factor in the evaluation of nerve injury and regeneration. PMID:26433750

  18. From nerve net to nerve ring, nerve cord and brain--evolution of the nervous system.

    PubMed

    Arendt, Detlev; Tosches, Maria Antonietta; Marlow, Heather

    2016-01-01

    The puzzle of how complex nervous systems emerged remains unsolved. Comparative studies of neurodevelopment in cnidarians and bilaterians suggest that this process began with distinct integration centres that evolved on opposite ends of an initial nerve net. The 'apical nervous system' controlled general body physiology, and the 'blastoporal nervous system' coordinated feeding movements and locomotion. We propose that expansion, integration and fusion of these centres gave rise to the bilaterian nerve cord and brain. PMID:26675821

  19. Myocardial commitment from human pluripotent stem cells: Rapid production of human heart grafts.

    PubMed

    Garreta, Elena; de Oñate, Lorena; Fernández-Santos, M Eugenia; Oria, Roger; Tarantino, Carolina; Climent, Andreu M; Marco, Andrés; Samitier, Mireia; Martínez, Elena; Valls-Margarit, Maria; Matesanz, Rafael; Taylor, Doris A; Fernández-Avilés, Francisco; Izpisua Belmonte, Juan Carlos; Montserrat, Nuria

    2016-08-01

    Genome editing on human pluripotent stem cells (hPSCs) together with the development of protocols for organ decellularization opens the door to the generation of autologous bioartificial hearts. Here we sought to generate for the first time a fluorescent reporter human embryonic stem cell (hESC) line by means of Transcription activator-like effector nucleases (TALENs) to efficiently produce cardiomyocyte-like cells (CLCs) from hPSCs and repopulate decellularized human heart ventricles for heart engineering. In our hands, targeting myosin heavy chain locus (MYH6) with mCherry fluorescent reporter by TALEN technology in hESCs did not alter major pluripotent-related features, and allowed for the definition of a robust protocol for CLCs production also from human induced pluripotent stem cells (hiPSCs) in 14 days. hPSCs-derived CLCs (hPSCs-CLCs) were next used to recellularize acellular cardiac scaffolds. Electrophysiological responses encountered when hPSCs-CLCs were cultured on ventricular decellularized extracellular matrix (vdECM) correlated with significant increases in the levels of expression of different ion channels determinant for calcium homeostasis and heart contractile function. Overall, the approach described here allows for the rapid generation of human cardiac grafts from hPSCs, in a total of 24 days, providing a suitable platform for cardiac engineering and disease modeling in the human setting. PMID:27179434

  20. The Right Gastroepiploic Artery Graft for Coronary Artery Bypass Grafting: A 30-Year Experience

    PubMed Central

    Suma, Hisayoshi

    2016-01-01

    Throughout its 30-year history, the right gastroepiploic artery (GEA) has been useful for in situ grafts in coronary artery bypass grafting (CABG). The early graft patency rate is high, and the late patency rate has improved by using the skeletonized GEA graft and proper target selection, which involves having a target coronary artery with a tight >90% stenosis. Total arterial revascularization with the internal thoracic artery and GEA grafts is an option for achieving better outcomes from CABG procedures. PMID:27525230

  1. Development of a guinea-pig model for potency/immunogenicity evaluation of diphtheria, tetanus acellular pertussis (DTaP) and Haemophilus influenzae type b polysaccharide conjugate vaccines.

    PubMed

    Gupta, R K; Anderson, R; Cecchini, D; Rost, B; Griffin, P; Benscoter, K; Xu, J; Montanez-Ortiz, L; Siber, G R

    1996-01-01

    We have evaluated a guinea pig model for assessing the immunogenicity of Haemophilus influenzae type b (Hib) polysaccharide-protein conjugate vaccines, acellular pertussis vaccine and combination vaccines-consisting of tetanus toxoid (TT), diphtheria toxoid (DT), acellular pertussis vaccine and Hib-TT (Hib-T) conjugate vaccine. The model was based on the United States (US) potency test for TT and DT which requires injection of guinea pigs with a single dose of undiluted vaccine. Guinea pigs showed dose-dependent antibody responses to pertussis toxoid (PTxd) and filamentous haemagglutinin (FHA), two important components of acellular pertussis vaccine. Antibody response of guinea pigs to commercially available Hib conjugate vaccines qualitatively resembled those of human infants. Unconjugated polyribosylribitolphosphate (PRP) was not immunogenic; PRP-D conjugate produced a low antibody response, HbOC, PRP-T (Merieux) and Hib-T (MPHBL) produced a low response to the first dose and a strong anamnestic response to the booster dose. PRP-OMP uniquely produced a strong response after the first dose which was boosted by the second dose. In preliminary experiments, injection of guinea pigs with the combined vaccine formulations consisting of TT, DT, whole cell or acellular pertussis vaccine (Ptxd and FHA) and Hib-T conjugate showed that these vaccines were immunogenic when combined, with some effects on the antibody responses of certain components. This model for testing potency/immunogenicity of combined vaccines substantially reduces the number of animals needed to test each lot of vaccine. To reduce the use of animals in testing vaccines further, we propose the use of a Vero cell assay for titrating diphtheria antitoxin and ELISA for measuring IgG antibody to tetanus toxin. The guinea pig model may also be useful for evaluating combination vaccines. PMID:8785957

  2. Polyether-polyester graft copolymer

    NASA Technical Reports Server (NTRS)

    Bell, Vernon L. (Inventor)

    1987-01-01

    Described is a polyether graft polymer having improved solvent resistance and crystalline thermally reversible crosslinks. The copolymer is prepared by a novel process of anionic copolymerization. These polymers exhibit good solvent resistance and are well suited for aircraft parts. Previous aromatic polyethers, also known as polyphenylene oxides, have certain deficiencies which detract from their usefulness. These commercial polymers are often soluble in common solvents including the halocarbon and aromatic hydrocarbon types of paint thinners and removers. This limitation prevents the use of these polyethers in structural articles requiring frequent painting. In addition, the most popular commercially available polyether is a very high melting plastic. This makes it considerably more difficult to fabricate finished parts from this material. These problems are solved by providing an aromatic polyether graft copolymer with improved solvent resistance and crystalline thermally reversible crosslinks. The graft copolymer is formed by converting the carboxyl groups of a carboxylated polyphenylene oxide polymer to ionic carbonyl groups in a suitable solvent, reacting pivalolactone with the dissolved polymer, and adding acid to the solution to produce the graft copolymer.

  3. 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

  4. Synthesis and characterization of macromolecular layers grafted to polymer surfaces

    NASA Astrophysics Data System (ADS)

    Burtovyy, Oleksandr

    membranes modified with a reactive anchoring layer can be successfully used to build membrane assemblies by incorporating silica, aluminum, or titanium oxide microparticles as spacers. It is expected that the proposed approaches for the surface modification of the membranes and for the generation of multilayered membrane assemblies can be employed straightforwardly to provide an efficient platform for fabrication of breathable protective materials. Characterization of modified membranes with a cantilever-based method, which can be used for prediction of properties and behavior of thin grafted films, is reported. This technique can be used as a method for fast screening of modified membranes. The method is very robust and capable of detecting very small quantities of substance adsorbed; kinetics of the process can be tracked, as well. This approach can be further developed as a handheld sensor for early warning of the presence of chemical vapors and nerve agents.

  5. Sensitivity of Allium and Nicotiana in cellular and acellular comet assays to assess differential genotoxicity of direct and indirect acting mutagens.

    PubMed

    Bandyopadhyay, Atrayee; Mukherjee, Anita

    2011-05-01

    We have evaluated the extent of DNA damage induced by direct and indirect mutagens by cellular and acellular comet assays in two plant systems, Nicotiana tabacum (wild type tobacco) and Allium cepa (common onion). The objectives of this study were: (1) to generate dose-response curves for DNA migration values from root and shoot nuclei of A. cepa and N. tabacum treated with the direct acting mutagens, ethyl methanesulphonate (EMS), hydrogen peroxide (H(2)O(2)) and the indirect acting mutagen, cadmium chloride (CdCl(2)), (2) to assess the differential response between isolated nuclei and nuclei of root and shoot and of both plants and (3) to examine the differences of sensitivity between direct and indirect acting mutagens by cellular and acellular comet assays. Similar sensitivities were evident in both plant systems to direct and indirect acting mutagens. The combination of cellular and acellular comet assays provided valuable insight to the mode of action of the genotoxicants used. The data obtained demonstrated the estimable capacity of the two plant systems to evaluate genotoxicity under different stress conditions and suggests Allium is a more desirable test system for rapid monitoring of genotoxicity. PMID:21237510

  6. Chitosan conduits combined with nerve growth factor microspheres repair facial nerve defects

    PubMed Central

    Liu, Huawei; Wen, Weisheng; Hu, Min; Bi, Wenting; Chen, Lijie; Liu, Sanxia; Chen, Peng; Tan, Xinying

    2013-01-01

    Microspheres containing nerve growth factor for sustained release were prepared by a compound method, and implanted into chitosan conduits to repair 10-mm defects on the right buccal branches of the facial nerve in rabbits. In addition, chitosan conduits combined with nerve growth factor or normal saline, as well as autologous nerve, were used as controls. At 90 days post-surgery, the muscular atrophy on the right upper lip was more evident in the nerve growth factor and normal sa-line groups than in the nerve growth factor-microspheres and autologous nerve groups. physiological analysis revealed that the nerve conduction velocity and amplitude were significantly higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. Moreover, histological observation illustrated that the di-ameter, number, alignment and myelin sheath thickness of myelinated nerves derived from rabbits were higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. These findings indicate that chitosan nerve conduits bined with microspheres for sustained release of nerve growth factor can significantly improve facial nerve defect repair in rabbits. PMID:25206635

  7. Chitosan conduits combined with nerve growth factor microspheres repair facial nerve defects.

    PubMed

    Liu, Huawei; Wen, Weisheng; Hu, Min; Bi, Wenting; Chen, Lijie; Liu, Sanxia; Chen, Peng; Tan, Xinying

    2013-11-25

    Microspheres containing nerve growth factor for sustained release were prepared by a compound method, and implanted into chitosan conduits to repair 10-mm defects on the right buccal branches of the facial nerve in rabbits. In addition, chitosan conduits combined with nerve growth factor or normal saline, as well as autologous nerve, were used as controls. At 90 days post-surgery, the muscular atrophy on the right upper lip was more evident in the nerve growth factor and normal sa-line groups than in the nerve growth factor-microspheres and autologous nerve groups. physiological analysis revealed that the nerve conduction velocity and amplitude were significantly higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. Moreover, histological observation illustrated that the di-ameter, number, alignment and myelin sheath thickness of myelinated nerves derived from rabbits were higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. These findings indicate that chitosan nerve conduits bined with microspheres for sustained release of nerve growth factor can significantly improve facial nerve defect repair in rabbits. PMID:25206635

  8. Cranial Nerves IX, X, XI, and XII

    PubMed Central

    Sanders, Richard D.

    2010-01-01

    This article concludes the series on cranial nerves, with review of the final four (IX–XII). To summarize briefly, the most important and common syndrome caused by a disorder of the glossopharyngeal nerve (craniel nerve IX) is glossopharyngeal neuralgia. Also, swallowing function occasionally is compromised in a rare but disabling form of tardive dyskinesia called tardive dystonia, because the upper motor portion of the glossopharyngel nerve projects to the basal ganglia and can be affected by lesions in the basal ganglia. Vagus nerve funtion (craniel nerve X) can be compromised in schizophrenia, bulimia, obesity, and major depression. A cervical lesion to the nerve roots of the spinal accessory nerve (craniel nerve XI) can cause a cervical dystonia, which sometimes is misdiagnosed as a dyskinesia related to neuroleptic use. Finally, unilateral hypoglossal (craniel nerve XII) nerve palsy is one of the most common mononeuropathies caused by brain metastases. Supranuclear lesions of cranial nerve XII are involved in pseudobulbar palsy and ALS, and lower motor neuron lesions of cranial nerve XII can also be present in bulbar palsy and in ALS patients who also have lower motor neuron involvement. This article reviews these and other syndromes related to cranial nerves IX through XII that might be seen by psychiatry. PMID:20532157

  9. What Protects Certain Nerves from Stretch Injury?

    PubMed

    Schraut, Nicholas B; Walton, Sharon; Bou Monsef, Jad; Shott, Susan; Serici, Anthony; Soulii, Lioubov; Amirouche, Farid; Gonzalez, Mark H; Kerns, James M

    2016-01-01

    The human tibial nerves is less prone to injury following joint arthroplasty compared with the peroneal nerves. Besides the anatomical distribution, other features may confer protection from stretch injury. We therefore examined the size, shape and connective tissue distribution for the two nerves. The tibial and peroneal nerves from each side of nine fresh human cadavers we reharvested mid-thigh. Proximal segments manually stretched 20%-25% were fixed in aldehyde, while the adjacent distal segments were fixed in their natural length. Paraffin sections stained by Masson's trichrome method for connective tissue were examined by light microscopy. Tibial nerves had 2X more fascicles compared with the peroneal, but the axonal content appeared similar. Analysis showed that neither nerve had a significant reduction in cross sectional area of the fascicles following stretch. However, fascicles from stretched tibial nerves become significantly more oval compared with those from unstretched controls and peroneal nerves. Tibial nerves had a greater proportion that was extrafascicular tissue (50-55%) compared with peroneal nerves (38%-42%). This epineurium was typically adipose tissue. Perineurial thickness in both nerves was directly related to fascicular size. Tibial nerves have several unique histological features associated with size, shape and tissue composition compared with the peroneal nerve. We suggest that more fascicles with their tightly bound perineurium and more robust epineurium afford protection against stretch injury. Mechanical studies should clarify how size and shape contribute to nerve protection and/or neurapraxia. PMID:26529568

  10. Vascular grafting strategies in coronary intervention

    NASA Astrophysics Data System (ADS)

    Knight, Darryl; Gillies, Elizabeth; Mequanint, Kibret

    2014-06-01

    With the growing need for coronary revascularizations globally, several strategies to restore blood flow to the heart have been explored. Bypassing the atherosclerotic coronary arteries with autologous grafts, synthetic prostheses and tissue-engineered vascular grafts continue to be evaluated in search of a readily available vascular graft with clinically acceptable outcomes. The development of such a vascular graft including tissue engineering approaches both in situ and in vitro is herein reviewed, facilitating a detailed comparison on the role of seeded cells in vascular graft patency.

  11. Preventing Phrenic Nerve Stimulation by a Patch Insulation in an Intact Swine Heart Model

    PubMed Central

    Hung, Yi-Wen; Hsieh, Yu-Cheng; Cheng, Chien-Ming; Wang, Kuo-Yang

    2014-01-01

    Introduction Phrenic nerve stimulation (PNS) could be prevented by a silastic patch over the epicardial lead. We studied the effects in preventing PNS by placing a silastic patch directly over an epicardial lead or placing a graft around the phrenic nerve (PN). Methods and Results Fourteen Lanyu swine were enrolled. A bipolar lead was placed epicardially on the left ventricle (LV) inferior to the PN. An implantable cardioverter-defibrillator (ICD) lead was placed into the right ventricle (RV). The maximal influential distance (MID) was measured under 3 pacing configurations to express the influential electrical field on the PN. The threshold of the LV and PN were evaluated epicardially. Then, PTFE patches of different sizes (10×10 mm, 20×20 mm and 30×30 mm) were placed between the LV lead and PN to study the rise in PN threshold in 7 swine. On the other hand, the PN were surrounded by a PTFE graft of different lengths (10 mm, 20 mm, and 30 mm) in the remaining 7 swine. LV-bipolar pacing showed the shortest MID when compared to the other 2 unipolar pacing configurations at pacing voltage of 10 V. The patch was most effective in preventing PNS during LV-bipolar pacing. PNS was prevented under all circumstances with a larger PTFE patch (30×30 mm) or long graft (30 mm). Conclusions PNS was avoided by placing a PTFE patch over the LV lead or a graft around the PN despite pacing configurations. Hence if PNS persisted during CRT implantation, a PTFE patch on the LV lead or a graft around the PN could be considered. PMID:25033271

  12. Modified and Grafted Coronectomy: A New Technique and a Case Report with Two-Year Followup

    PubMed Central

    Leizerovitz, Michael; Leizerovitz, Olga

    2013-01-01

    Purpose. A standard coronectomy (intentional partial odontectomy) is recommended for mandibular third molar (MTM) extraction cases with a high risk of inferior alveolar nerve injury (IANI). However, complications such as inadvertent intraoperative root removal, post-op root migration, second molar (MSM) periodontal defects and others do exist. This report presents a new technique, the Modified and Grafted Coronectomy (MGC), describes the measures to prevent or minimize the known drawbacks of the standard coronectomy, and reviews the literature for comparison with three other IANI-prevention techniques. Materials and Methods. MGC was performed on two MTMs with nerve involvement and severe periodontal pockets on the distal of MSM. Modifications were: stabilizing the root stump to prevent intraoperative movement, creation of a large intrabony space for bone graft material, and grafting for periodontal healing while minimizing the possibility of post-op root migration. Results. Excellent overall periodontal improvement, with probing depths reduced to 3-4 mm. Panoramic radiograph displayed remarkable bone regeneration. No residual root migration was evident at the two year follow up. Conclusion. MGC may be a good alternative, especially in cases with periodontal defects on the distal of MSM. It may also help to minimize inadvertent intraoperative root removal and postoperative root migration. PMID:23710376

  13. Inhalational exposure to nerve agents.

    PubMed

    Niven, Alexander S; Roop, Stuart A

    2004-03-01

    The respiratory system plays a major role in the pathogenesis of nerve agent toxicity. It is the major route of entry and absorption of nerve agent vapor, and respiratory failure is the most common cause of death follow-ing exposure. Respiratory symptoms are mediated by chemical irritation,muscarinic and nicotinic receptor overstimulation, and central nervous system effects. Recent attacks have demonstrated that most patients with an isolated vapor exposure developed respiratory symptoms almost immediately. Most patients had only mild and transient respiratory effects, and those that did develop significant respiratory compromise did so rapidly. These observations have significant ramifications on triage of patients in a mass-casualty situation, because patients with mild-to-moderate exposure to nerve agent vapor alone do not require decontamination and are less likely to develop progressive symptoms following initial antidote therapy. Limited data do not demonstrate significant long-term respiratory effects following nerve agent exposure and treatment. Provisions for effective respiratory protection against nerve agents is a vital consideration in any emergency preparedness or health care response plan against a chemical attack. PMID:15062227

  14. An update on coronary bypass graft intervention

    PubMed Central

    Dash, Debabrata

    2014-01-01

    Coronary artery bypass grafting (CABG) remains one of the most common surgical procedures. In spite of great advancements like arterial grafts and off-pump bypass procedure, recurrent ischaemia may ensue with the lesions of the graft. Early postoperative ischaemia (<30 days) is due to graft occlusion or stenosis, and percutaneous coronary intervention (PCI) is frequently feasible. Late postoperative ischaemia (>3 years) is most often due to a saphenous vein graft (SVG) lesion. Multiple diseased grafts, reduced left ventricular function, and available arterial conduits favour repeat CABG, whereas, a patent left internal mammary artery to left anterior descending favours PCI. Embolic protection reduces atheroembolic myocardial infarction during PCI of SVG and should be routinely used in treatment of SVG lesions. A variety of vasodilators may reduce the risk of or mitigate the consequences of no-reflow. Drug-eluting stents reduce restenosis in SVG grafts, and have become the default strategy for many interventionalists. PMID:27326165

  15. Renal graft irradiation in acute rejection

    SciTech Connect

    Pilepich, M.V.; Sicard, G.A.; Breaux, S.R.; Etheredge, E.E.; Blum, J.; Anderson, C.B.

    1983-03-01

    To evaluate the effect of graft irradiation in the treatment of acute rejection of renal transplants, a randomized study was conducted from 1978 to 1981. Patients with acute rejection were given standard medical management in the form of intravenous methylprednisolone, and were chosen randomly to receive either graft irradiation (175 rads every other day, to a total of 525 rads) or simulated (sham) irradiation. Eighty-three rejections occurring in 64 grafts were randomized to the protocol. Rejection reversal was recorded in 84.5% of control grafts and 75% of the irradiated grafts. Recurrent rejections were more frequent and graft survival was significantly lower in the irradiated group (22%) than in the control group (54%). Graft irradiation does not appear to be beneficial in the treatment of acute rejection of renal transplants when used in conjunction with high-dose steroids.

  16. Neurotrophin expression and laryngeal muscle pathophysiology following recurrent laryngeal nerve transection

    PubMed Central

    WANG, BAOXIN; YUAN, JUNJIE; XU, JIAFENG; XIE, JIN; WANG, GUOLIANG; DONG, PIN

    2016-01-01

    Laryngeal palsy often occurs as a result of recurrent laryngeal or vagal nerve injury during oncological surgery of the head and neck, affecting quality of life and increasing economic burden. Reinnervation following recurrent laryngeal nerve (RLN) injury is difficult despite development of techniques, such as neural anastomosis, nerve grafting and creation of a laryngeal muscle pedicle. In the present study, due to the limited availability of human nerve tissue for research, a rat model was used to investigate neurotrophin expression and laryngeal muscle pathophysiology in RLN injury. Twenty-five male Sprague-Dawley rats underwent right RLN transection with the excision of a 5-mm segment. Vocal fold movements, vocalization, histology and immunostaining were evaluated at different time-points (3, 6, 10 and 16 weeks). Although vocalization was restored, movement of the vocal fold failed to return to normal levels following RLN injury. The expression of brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor differed in the thyroarytenoid (TA) and posterior cricoarytenoid muscles. The number of axons did not increase to baseline levels over time. Furthermore, normal muscle function was unlikely with spontaneous reinnervation. During regeneration following RLN injury, differences in the expression levels of neurotrophic factors may have resulted in preferential reinnervation of the TA muscles. Data from the present study indicated that neurotrophic factors may be applied for restoring the function of the laryngeal nerve following recurrent injury. PMID:26677138

  17. Facial-hypoglossal nerve anastomosis using laser nerve welding.

    PubMed

    Hwang, Kun; Kim, Sun Goo; Kim, Dae Joong

    2006-07-01

    The aim of this study is to compare laser nerve welding to microsurgical suturing of hypoglossal-facial nerve anastomosis (HFA), and a result of immediate to delayed repair, and to evaluate the effect of laser nerve welding on HFA for reanimation of facial palsy. The first group of five rats underwent immediate HFA by microsurgical suturing and the second group of five rats by CO2 laser welding. The third group of five rats underwent delayed HFA by microsurgical suturing, and the fourth group of five rats by laser nerve welding. The fifth group of five rats served as controls, with intact hypoglossal and facial nerve. In all rats of the four different treatment groups, cholera toxin B subunit (CTb) was injected in the epineurium distal to the anastomosis site on the postoperative 6th week and in the normal hypoglossal nerve in the five rats of the control group. Neurons labeled CTb of hypoglossal nuclei were positive immunohistochemically, and the numbers were counted. In the immediate HFA groups, CTb-positive neurons were 751 +/- 247 in the laser welding group (n = 5) and 888 +/- 60 in the microsurgical suturing group (n = 5). There was no significant difference (P = 0.117). In the delayed HFA groups, CTb-positive neurons were 749 +/- 54 in the laser welding group (n = 5) and 590 +/- 169 in the microsurgical suturing group (n = 5). The difference was not significant (P = 0.116). There was no significant difference between immediate and delayed anastomosis in the laser welding group (P = 0.600), but there was significance between immediate and delayed anastomosis in the microsurgical suturing group (P = 0.009). Injected CTb in intact hypoglossal neurons (n = 5) were labeled 1,003 +/- 52. No dehiscence in the laser welding site of nerve anastomosis was seen at the time of re-exploration for injection of CTb in all 10 rats. This study shows that the regeneration of anastomosed hypoglossal-facial nerve was affected similarly by laser welding and microsurgical suturing

  18. Biology of polypropylene/polyglactin 910 grafts.

    PubMed

    Barbolt, Thomas A

    2006-06-01

    The biological evaluation of polypropylene (PP)/polyglactin 910 grafts was reviewed including regulatory considerations, biocompatibility assessment, tissue reaction and integration, and infection potentiation of these synthetic materials used in urogynecological surgical procedures. The physical characteristics of the grafts including base composition, monofilament vs multifilament, and non-absorbable vs absorbable materials were compared. Grafts were implanted in rats to evaluate the tissue reaction and integration characteristics of the materials over time. Grafts were also implanted in mice and inoculated with Staphylococcus aureus to assess the potential for bacterial attachment and growth. The tissue reaction to PP/polyglactin 910 grafts was characterized by minimal to mild inflammation with some qualitative differences related to the physical construction of the different grafts. The tissue reaction to polyglactin 910 mesh was also mild but resolved after the material was absorbed 70 days post-implantation. The integration of PP/polyglactin 910 grafts by fibrosis with surrounding tissue was initially mild for all materials but decreased over time for the lightweight and multifilament PP-based grafts, including a graft with an absorbable polyglactin 910 component. Residual fibrosis was not observed for the graft constructed from polyglactin 910 alone. Grafts constructed from PP did not potentiate infection after inoculation with S. aureus whereas the number of bacteria recovered from naturally derived collagen-based materials increased by three to four logs. The biological performance of PP/polyglactin 910 grafts is dependent on multiple factors including the composition and physical construction of the base materials, the overall biocompatibility of the materials, particularly tissue reaction and integration of the grafts, and the resistance of the grafts to bacterial attachment and growth. PMID:16738744

  19. A precision mechanical nerve stimulator

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

    1988-01-01

    An electromechanical device, used to apply and monitor stimulating pulses to a mammalian motor nerve, has been successfully developed at NASA Langley Research Center. Two existing force transducers, a flight skin friction balance and a miniature skin friction balance which were designed for making aerodynamic drag measurements, were modified and incorporated to form this precision instrument. The nerve stimulator is a type one servomechanism capable of applying and monitoring stimulating pulses of 0 to 10 grams with a precision of better than +/- 0.05 grams. Additionally, the device can be independently used to apply stimulating pulses by displacing the nerve from 0 to 0.25 mm with a precision of better than +/- 0.001 mm while measuring the level of the load applied.

  20. [Paraganglioma of the vagus nerve].

    PubMed

    Torres-Carranza, E; Infante-Cossío, P; García-Perla, A; Belmonte, R; Menéndez, J; Gutiérrez-Pérez, J L

    2006-06-01

    Paragangliomas of the vagus nerve are uncommon vascular benign neoplasms of neuroectodermic origin. Initial clinical manifestation is usually as an asymptomatic cervical mass, although sometimes may cause lower cranial nerve palsies. These paragangliomas seldom associate to high levels of circulating catecholamines. Diagnosis is based on the clinics aided by imaging, where CT and MRI play an important role. Angiography is not only diagnostic, but it also allows preoperative embolization of the mass. Most accepted treatment is surgical removal, even though some paragangliomas are suitable for radiation therapy in very specific patients. In this paper we describe a new case of paraganglioma of the vagus nerve in a cervical location, with hypertensive episodes and high catecholamine-levels. The authors review the literature describing the clinical presentation, the diagnosis and the treatment of this rare lesion. PMID:16855784

  1. Facial nerve paralysis in children

    PubMed Central

    Ciorba, Andrea; Corazzi, Virginia; Conz, Veronica; Bianchini, Chiara; Aimoni, Claudia

    2015-01-01

    Facial nerve palsy is a condition with several implications, particularly when occurring in childhood. It represents a serious clinical problem as it causes significant concerns in doctors because of its etiology, its treatment options and its outcome, as well as in little patients and their parents, because of functional and aesthetic outcomes. There are several described causes of facial nerve paralysis in children, as it can be congenital (due to delivery traumas and genetic or malformative diseases) or acquired (due to infective, inflammatory, neoplastic, traumatic or iatrogenic causes). Nonetheless, in approximately 40%-75% of the cases, the cause of unilateral facial paralysis still remains idiopathic. A careful diagnostic workout and differential diagnosis are particularly recommended in case of pediatric facial nerve palsy, in order to establish the most appropriate treatment, as the therapeutic approach differs in relation to the etiology. PMID:26677445

  2. Facial nerve paralysis in children.

    PubMed

    Ciorba, Andrea; Corazzi, Virginia; Conz, Veronica; Bianchini, Chiara; Aimoni, Claudia

    2015-12-16

    Facial nerve palsy is a condition with several implications, particularly when occurring in childhood. It represents a serious clinical problem as it causes significant concerns in doctors because of its etiology, its treatment options and its outcome, as well as in little patients and their parents, because of functional and aesthetic outcomes. There are several described causes of facial nerve paralysis in children, as it can be congenital (due to delivery traumas and genetic or malformative diseases) or acquired (due to infective, inflammatory, neoplastic, traumatic or iatrogenic causes). Nonetheless, in approximately 40%-75% of the cases, the cause of unilateral facial paralysis still remains idiopathic. A careful diagnostic workout and differential diagnosis are particularly recommended in case of pediatric facial nerve palsy, in order to establish the most appropriate treatment, as the therapeutic approach differs in relation to the etiology. PMID:26677445

  3. Chemical warfare. Nerve agent poisoning.

    PubMed

    Holstege, C P; Kirk, M; Sidell, F R

    1997-10-01

    The threat of civilian and military casualties from nerve agent exposure has become a greater concern over the past decade. After rapidly assessing that a nerve agent attack has occurred, emphasis must be placed on decontamination and protection of both rescuers and medical personnel from exposure. The medical system can become rapidly overwhelmed and strong emotional reactions can confuse the clinical picture. Initially, care should first be focused on supportive care, with emphasis toward aggressive airway maintenance and decontamination. Atropine should be titrated, with the goal of therapy being drying of secretions and the resolution of bronchoconstriction and bradycardia. Early administration of pralidoxime chloride maximizes antidotal efficacy. Benzodiazepines, in addition to atropine, should be administered if seizures develop. Early, aggressive medical therapy is the key to prevention of the morbidity and mortality associated with nerve agent poisoning. PMID:9330846

  4. Patient outcome after surgical management of the spinal accessory nerve injury: A long-term follow-up study

    PubMed Central

    Göransson, Harry; Leppänen, Olli V; Vastamäki, Martti

    2016-01-01

    Objectives: A lesion in the spinal accessory nerve is typically iatrogenic: related to lymph node biopsy or excision. This injury may cause paralysis of the trapezius muscle and thus result in a characteristic group of symptoms and signs, including depression and winging of the scapula, drooped shoulder, reduced shoulder abduction, and pain. The elements evaluated in this long-term follow-up study include range of shoulder motion, pain, patients’ satisfaction, delay of surgery, surgical procedure, occupational status, functional outcome, and other clinical findings. Methods: We reviewed the medical records of a consecutive 37 patients (11 men and 26 women) having surgery to correct spinal accessory nerve injury. Neurolysis was the procedure in 24 cases, direct nerve repair for 9 patients, and nerve grafting for 4. Time elapsed between the injury and the surgical operation ranged from 2 to 120 months. The patients were interviewed and clinically examined after an average of 10.2 years postoperatively. Results: The mean active range of movement of the shoulder improved at abduction 44° (43%) in neurolysis, 59° (71%) in direct nerve repair, and 30° (22%) in nerve-grafting patients. No or only slight atrophy of the trapezius muscle was observable in 75%, 44%, and 50%, and no or controllable pain was observable in 63%, 56%, and 50%. Restriction of shoulder abduction preceded deterioration of shoulder flexion. Patients’ overall dissatisfaction with the state of their upper extremity was associated with pain, lower strength in shoulder movements, and occupational problems. Conclusion: We recommend avoiding unnecessary delay in the exploration of the spinal accessory nerve, if a neural lesion is suspected. PMID:27152195

  5. Peripheral nerve disease in pregnancy.

    PubMed

    Klein, Autumn

    2013-06-01

    Neuropathies during pregnancy and the postpartum period are common and are usually due to compression around pregnancy and childbirth. The most common peripheral neuropathies are Bell's palsy, carpal tunnel syndrome (CTS), and lower extremity neuropathies. Although most neuropathies are usually reversible, associated disabilities or morbidities can limit functioning and require therapy. Nerve conduction study tests and imaging should only be considered if symptoms are unusual or prolonged. Some neuropathies may be associated with preeclampsia or an inherent underlying neuropathy that increases the risk of nerve injury. All neuropathies in pregnancy should be followed as some may be persistent and require follow-up. PMID:23563878

  6. Nerve lesioning with direct current

    NASA Astrophysics Data System (ADS)

    Ravid, E. Natalie; Shi Gan, Liu; Todd, Kathryn; Prochazka, Arthur

    2011-02-01

    Spastic hypertonus (muscle over-activity due to exaggerated stretch reflexes) often develops in people with stroke, cerebral palsy, multiple sclerosis and spinal cord injury. Lesioning of nerves, e.g. with phenol or botulinum toxin is widely performed to reduce spastic hypertonus. We have explored the use of direct electrical current (DC) to lesion peripheral nerves. In a series of animal experiments, DC reduced muscle force by controlled amounts and the reduction could last several months. We conclude that in some cases controlled DC lesioning may provide an effective alternative to the less controllable molecular treatments available today.

  7. Endovascular Stent-Graft Repair as a Late Secondary Procedure After Previous Aortic Grafts

    SciTech Connect

    Matsagas, Miltiadis I. Anagnostopoulos, Constantine E.; Papakostas, John C.; DeRose, Joseph J.; Siminelakis, Stavros; Katsouras, Christos S.; Toumpoulis, Ioannis K.; Drossos, George E.; Michalis, Lampros K.

    2006-08-15

    Thoracic and abdominal aortic endovascular procedures as alternatives to aortic reoperations were studied in three different cases. An anastomotic aneurysm after previous thoracic aortic graft for coarctation, a second-stage elephant trunk repair (descending thoracic aortic aneurysm), and a secondary aneurysm proximal to a previous abdominal aortic graft were successfully treated with endovascular stent-grafts. During the follow-up period no lethal events or major aortic or graft-related complications were observed, except a type II endoleak in the anastomotic aortic aneurysm case. An endovascular stent-graft can be safely deployed into a previously implanted vascular graft, avoiding repeat surgery.

  8. Perineural fat grafting in the treatment of painful end-neuromas of the upper limb: a pilot study.

    PubMed

    Vaienti, L; Merle, M; Battiston, B; Villani, F; Gazzola, R

    2013-01-01

    The purpose of this study was to evaluate the effectiveness and middle-term durability of the results achieved with perineural fat grafting of painful neuromas of the upper limb. We retrospectively analysed eight patients, affected by eight neuromas, treated by neuroma excision and fat grafting around the proximal nerve stump. Clinical parameters, the disabilities of the arm shoulder and hand score, and the visual analogue scale were recorded at 2, 6 and 12 months after surgery. A reduction of 23.2% was observed in the mean disabilities of the arm shoulder and hand scores at 12 months. The spontaneous baseline visual analogue scale score showed a mean improvement of 22% at 12 months, although not this was not statistically significant. Perineural fat grafting is a quick and useful procedure and could represent a useful primary operation in the treatment of pain syndromes of neuropatic origin. PMID:22415427

  9. Nerve supply to the pelvis (image)

    MedlinePlus

    The nerves that branch off the central nervous system (CNS) provide messages to the muscles and organs for normal ... be compromised. In multiple sclerosis, the demyelinization of nerve cells may lead to bowel incontinence, bladder problems ...

  10. Infraspinatus muscle atrophy from suprascapular nerve compression.

    PubMed

    Cordova, Christopher B; Owens, Brett D

    2014-02-01

    Muscle weakness without pain may signal a nerve compression injury. Because these injuries should be identified and treated early to prevent permanent muscle weakness and atrophy, providers should consider suprascapular nerve compression in patients with shoulder muscle weakness. PMID:24463748

  11. Fabrication of bioactive conduits containing the fibroblast growth factor 1 and neural stem cells for peripheral nerve regeneration across a 15 mm critical gap.

    PubMed

    Ni, Hsiao-Chiang; Tseng, Ting-Chen; Chen, Jeng-Rung; Hsu, Shan-Hui; Chiu, Ing-Ming

    2013-09-01

    Nerve conduits are often used in combination with bioactive molecules and stem cells to enhance peripheral nerve regeneration. In this study, the acidic fibroblast growth factor 1 (FGF1) was immobilized onto the microporous/micropatterned poly (D, L-lactic acid) (PLA) nerve conduits after open air plasma treatment. PLA substrates grafted with chitosan in the presence of a small amount of gold nanoparticles (nano Au) showed a protective effect on the activity of the immobilized FGF1 in vitro. Different conduits were tested for their ability to bridge a 15 mm critical gap defect in a rat sciatic nerve injury model. Axon regeneration and functional recovery were evaluated by histology, walking track analysis and electrophysiology. Among different conduits, PLA conduits grafted with chitosan-nano Au and the FGF1 after plasma activation had the greatest regeneration capacity and functional recovery in the experimental animals. When the above conduit was seeded with aligned neural stem cells, the efficacy was further enhanced and it approached that of the autograft group. This work suggested that microporous/micropatterned nerve conduits containing bioactive growth factors may be successfully fabricated by micropatterning techniques, open plasma activation, and immobilization, which, combined with aligned stem cells, may synergistically contribute to the regeneration of the severely damaged peripheral nerve. PMID:23880639

  12. Vein graft in stapes surgery.

    PubMed

    Kamal, S A

    1996-03-01

    Sealing the opening of the oval window during stapes surgery is essential; it prevents postoperative complications, such as perilymph fistula and sensorineural hearing loss. In this small series of 269 cases with otosclerosis, tympanosclerosis, and congenital ossicular abnormality, vein grafting was used to seal the opening of the footplate. Hearing improvement after surgery was acceptable, and none had total hearing loss or perilymphatic fistula. World literature from the last half of this century on grafting the oval window is reviewed. Absorbable gelatin sponge (Gelfoam) seems to be causing more complications, so its use is highly discouraged. Temporalis fascia, fat, and perivenous loose areolar tissue have been used by different authors at different times in footplate surgery. The opening created in the oval window during stapes surgery must not be left uncovered. PMID:8723953

  13. Evaluating the Effectiveness of Cryopreserved Acellular Dermal Matrix in Immediate Expander-Based Breast Reconstruction: A Comparison Study

    PubMed Central

    Kim, So-Young; Lim, So Young; Mun, Goo-Hyun; Bang, Sa-Ik; Oh, Kap Sung

    2015-01-01

    Background CGCryoDerm was first introduced in 2010 and offers a different matrix preservation processes for freezing without drying preparation. From a theoretical perspective, CGCryoDerm has a more preserved dermal structure and more abundant growth factors for angiogenesis and recellularization. In the current study, the authors performed a retrospective study to evaluate freezing- and freeze-drying-processed acellular dermal matrix (ADM) to determine whether any differences were present in an early complication profile. Methods Patients who underwent ADM-assisted tissue expander placement for two stage breast reconstruction between January of 2013 and March of 2014 were retrospectively reviewed and divided into two groups based on the types of ADM-assisted expander reconstruction (CGDerm vs. CGCryoDerm). Complications were divided into four main categories and recorded as follows: seroma, hematoma, infection, and mastectomy skin flap necrosis. Results In a total of 82 consecutive patients, the CGCryoDerm group had lower rates of seroma when compared to the CGDerm group without statistical significance (3.0% vs. 10.2%, P=0.221), respectively. Other complications were similar in both groups. Reconstructions with CGCryoDerm were found to have a significantly longer period of drainage when compared to reconstructions with CGDerm (11.91 days vs. 10.41 days, P=0.043). Conclusions Preliminary findings indicate no significant differences in early complications between implant/expander-based reconstructions using CGCryoderm and those using CGDerm. PMID:26015887

  14. Characterization of bionanocomposite scaffolds comprised of amine-functionalized single-walled carbon nanotubes crosslinked to an acellular porcine tendon.

    PubMed

    Deeken, Corey R; Cozad, Matthew J; Bachman, Sharon L; Ramshaw, Bruce J; Grant, Sheila A

    2011-03-01

    Carbon nanotubes (CNT) possess many unique electrical and mechanical properties that make them useful for a variety of industrial and biomedical applications. They are especially attractive materials for biomedical applications since their dimensions are similar to components of the extracellular matrix. In this study, amine-functionalized single-walled carbon nanotubes were crosslinked to an acellular porcine diaphragm tendon. The resulting bionanocomposite scaffolds were subjected to a number of materials characterization techniques including a collagenase assay, uniaxial tensile testing, modulated differential scanning calorimetry, and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy to determine whether the properties of the original extracellular matrix were altered by the treatment processes. A variety of SWCNT concentrations were investigated. While none of the conditions investigated resulted in bionanocomposites with significantly improved physicochemical properties, no detrimental effects were observed due to any of the processing steps. Future studies should be performed to determine if carbon nanotubes can influence cellular adhesion and function in order to promote rapid integration and remodeling. PMID:21254390

  15. Mineralization process during acellular cementogenesis in rat molars: a histochemical and immunohistochemical study using fresh-frozen sections.

    PubMed

    Yamamoto, Tsuneyuki; Domon, Takanori; Takahashi, Shigeru; Anjuman, Khan Ara Yasmin; Fukushima, Chifumi; Wakita, Minoru

    2007-03-01

    This study was designed to detect tissue non-specific alkaline phosphatase (TNSALP) by Azo-dye staining, calcium by glyoxal bis (2-hydroxyanil) (GBHA) staining, bone sialoprotein (BSP) and osteopontin (OPN) by immunoperoxidase staining in developing rat molars, and also to discuss the mineralization process during acellular cementogenesis. To restrain a reduction in histochemical and immunohistochemical reactions, fresh-frozen undemineralized sections were prepared. Where the epithelial sheath was intact, TNSALP reaction was observed in the dental follicle, but not in the epithelial sheath. With the onset of dentin mineralization, the BSP- and OPN-immunoreactive, initial cementum layer appeared. At this point, cementoblasts had shown intense TNSALP reaction and GBHA reactive particles (=calcium-GBHA complex) appeared on the root surface. With further development, the reaction of TNSALP and GBHA became weak on the root surface. Previous studies have shown that the initial cementum is fibril-poor and that matrix vesicles and calciferous spherules appear on the root surface only during the initial cementogenesis. The findings mentioned above suggest that: during the initial cementogenesis, cementoblasts release matrix vesicles which result in calciferous spherules, corresponding to the GBHA reactive particles. The calciferous spherules trigger the mineralization of the initial cementum. After principal fiber attachment, mineralization advances along collagen fibrils without matrix vesicles. PMID:17043865

  16. Acellular human glans extracellular matrix as a scaffold for tissue engineering: in vitro cell support and biocompatibility

    PubMed Central

    Egydio, Fernanda M.; Freitas, Luiz G.; Sayeg, Kleber; Laks, Marcus; Oliveira, Andréia S.; Almeida, Fernando G.

    2015-01-01

    ABSTRACT Objectives: Diseases of the genitourinary tract can lead to significant damage. Current reconstructive techniques are limited by tissue availability and compatibility. This study aims to assess if the decellularized human glans can be used as a biomaterial for penile reconstruction. Materials and Methods: Samples of the glans matrices were descellularized. We evaluate the presence of collagen type I and III, and elastic fibers. Biocompatibility assays were performed to assess the cytotoxic and non-cytotoxic interactions between the acellular matrix and 3T3 cells. The matrices were seeded with mesenchymal stem cells and were assessed for viability and integration of these cells. Biomechanical tests in native tissue, descellularized matrix and seeded matrix were performed to characterize their biomechanical properties. Results: The tissue architecture of the decellularized matrix of human glans was preserved as well as the maintenance of the biomechanical and biological properties. The analyzes of glans seeded with mesenchymal stem cells revealed the integration of these cells to the matrices, and its viability during two weeks “in vitro”. Conclusion: The decellularization process did not alter the biological and biomechanical characteristics of the human glans. When these matrices were seeded they were able to maintain the cells integrity and vitality. PMID:26689526

  17. Tissue performance of bladder following stretched electrospun silk fibroin matrix and bladder acellular matrix implantation in a rabbit model.

    PubMed

    Huang, Jian-Wen; Xu, Yue-Min; Li, Zhao-Bo; Murphy, Sean V; Zhao, Weixin; Liu, Qiang-Qiang; Zhu, Wei-Dong; Fu, Qiang; Zhang, Yao-Peng; Song, Lu-Jie

    2016-01-01

    The goal of this study was to investigate the tissue performance of bladder following stretched electrospun silk fibroin matrix (SESFM) implantation compared with bladder acellular matrix (BAM). We compared SESFM with BAM based on porosity and pore size. Scaffolds were separately transplanted into opposite walls of the bladder of 30 rabbits after stripping the bladder mucosa and smooth muscle (1.5 × 2.0 cm(2)). Gross anatomical observation, histological analysis and muscle contractility studies were performed at 2, 4, and 8 weeks post-op. SESFM has higher porosity and larger pore size compared with BAM (p < 0.05). At 2 weeks, the presence of vesical calculus was evident in 7/10 rabbits. Histological analysis showed that SESFM and BAM promoted similar degree of urothelium regeneration (p > 0.05). However, SESFM promoted a higher degree of smooth muscle and vessel regeneration compared to BAM (p < 0.05). In addition, muscle strips supported by SESFM displayed higher contractile responses to carbachol, KCl, and phenylephrine compared with BAM. At 8 weeks, both matrices elicited similar mild acute and chronic inflammatory reactions. Our results demonstrated that SESFM has greater ability to promote bladder tissue regeneration with structural and functional properties compared to BAM, and with similar biocompatibility. PMID:26148477

  18. High contrast microstructural visualization of natural acellular matrices by means of phase-based x-ray tomography

    PubMed Central

    Hagen, Charlotte K.; Maghsoudlou, Panagiotis; Totonelli, Giorgia; Diemoz, Paul C.; Endrizzi, Marco; Rigon, Luigi; Menk, Ralf-Hendrik; Arfelli, Fulvia; Dreossi, Diego; Brun, Emmanuel; Coan, Paola; Bravin, Alberto; De Coppi, Paolo; Olivo, Alessandro

    2015-01-01

    Acellular scaffolds obtained via decellularization are a key instrument in regenerative medicine both per se and to drive the development of future-generation synthetic scaffolds that could become available off-the-shelf. In this framework, imaging is key to the understanding of the scaffolds’ internal structure as well as their interaction with cells and other organs, including ideally post-implantation. Scaffolds of a wide range of intricate organs (esophagus, lung, liver and small intestine) were imaged with x-ray phase contrast computed tomography (PC-CT). Image quality was sufficiently high to visualize scaffold microarchitecture and to detect major anatomical features, such as the esophageal mucosal-submucosal separation, pulmonary alveoli and intestinal villi. These results are a long-sought step for the field of regenerative medicine; until now, histology and scanning electron microscopy have been the gold standard to study the scaffold structure. However, they are both destructive: hence, they are not suitable for imaging scaffolds prior to transplantation, and have no prospect for post-transplantation use. PC-CT, on the other hand, is non-destructive, 3D and fully quantitative. Importantly, not only do we demonstrate achievement of high image quality at two different synchrotron facilities, but also with commercial x-ray equipment, which makes the method available to any research laboratory. PMID:26657471

  19. Decreased Laminin Expression by Human Lung Epithelial Cells and Fibroblasts Cultured in Acellular Lung Scaffolds from Aged Mice

    PubMed Central

    Godin, Lindsay M.; Sandri, Brian J.; Wagner, Darcy E.; Meyer, Carolyn M.; Price, Andrew P.; Akinnola, Ifeolu; Weiss, Daniel J.; Panoskaltsis-Mortari, Angela

    2016-01-01

    The lung changes functionally and structurally with aging. However, age-related effects on the extracellular matrix (ECM) and corresponding effects on lung cell behavior are not well understood. We hypothesized that ECM from aged animals would induce aging-related phenotypic changes in healthy inoculated cells. Decellularized whole organ scaffolds provide a powerful model for examining how ECM cues affect cell phenotype. The effects of age on ECM composition in both native and decellularized mouse lungs were assessed as was the effect of young vs old acellular ECM on human bronchial epithelial cells (hBECs) and lung fibroblasts (hLFs). Native aged (1 year) lungs demonstrated decreased expression of laminins α3 and α4, elastin and fibronectin, and elevated collagen, compared to young (3 week) lungs. Proteomic analyses of decellularized ECM demonstrated similar findings, and decellularized aged lung ECM contained less diversity in structural proteins compared to young ECM. When seeded in old ECM, hBECs and hLFs demonstrated lower gene expression of laminins α3 and α4, respectively, as compared to young ECM, paralleling the laminin deficiency of aged ECM. ECM changes appear to be important factors in potentiating aging-related phenotypes and may provide clues to mechanisms that allow for aging-related lung diseases. PMID:26954258

  20. Persistence of T-cell immune response induced by two acellular pertussis vaccines in children five years after primary vaccination.

    PubMed

    Palazzo, Raffaella; Carollo, Maria; Bianco, Manuela; Fedele, Giorgio; Schiavoni, Ilaria; Pandolfi, Elisabetta; Villani, Alberto; Tozzi, Alberto E; Mascart, Françoise; Ausiello, Clara M

    2016-01-01

    The resurgence of pertussis suggests the need for greater efforts to understand the long-lasting protective responses induced by vaccination. In this paper we dissect the persistence of T memory responses induced by primary vaccination with two different acellular pertussis (aP) vaccines, hexavalent Hexavac® vaccine (Hexavac) (Sanofi Pasteur MSD) and Infanrix hexa® (Infanrix) (Glaxo-SmithKline Biologicals). We evaluated magnitude and duration of T-cell responses to pertussis toxin (PT) by measuring T-cell proliferation, cytokines (IL-2 and IFNγ) production and memory subsets in two groups of children 5 years after primary vaccination. Some of the enrolled children received only primary vaccination, while others had the pre-school boost dose. Positive T-cell responses to PT were detected in 36% of children. Percentage of responsive children, T-cell proliferation and CD4IL-2+ cells were significantly higher in the children primed with Hexavac than in those who received Infanrix vaccine. No major effects of the boost on PT-specific proliferation were observed. Overall, our data documented a persistence of T-cell memory against PT in a minor fraction of children 5 years after primary vaccination. The different responses induced by Hexavac and Infanrix vaccine could rely on differences in PT inactivation process or excipients/adjuvants formulations. PMID:26922984