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Sample records for acellular nerve grafts

  1. Acellular allogeneic nerve grafting combined with bone marrow mesenchymal stem cell transplantation for the repair of long-segment sciatic nerve defects: biomechanics and validation of mathematical models

    PubMed Central

    Li, Ya-jun; Zhao, Bao-lin; Lv, Hao-ze; Qin, Zhi-gang; Luo, Min

    2016-01-01

    We hypothesized that a chemically extracted acellular allogeneic nerve graft used in combination with bone marrow mesenchymal stem cell transplantation would be an effective treatment for long-segment sciatic nerve defects. To test this, we established rabbit models of 30 mm sciatic nerve defects, and treated them using either an autograft or a chemically decellularized allogeneic nerve graft with or without simultaneous transplantation of bone marrow mesenchymal stem cells. We compared the tensile properties, electrophysiological function and morphology of the damaged nerve in each group. Sciatic nerves repaired by the allogeneic nerve graft combined with stem cell transplantation showed better recovery than those repaired by the acellular allogeneic nerve graft alone, and produced similar results to those observed with the autograft. These findings confirm that a chemically extracted acellular allogeneic nerve graft combined with transplantation of bone marrow mesenchymal stem cells is an effective method of repairing long-segment sciatic nerve defects. PMID:27651781

  2. Acellular allogeneic nerve grafting combined with bone marrow mesenchymal stem cell transplantation for the repair of long-segment sciatic nerve defects: biomechanics and validation of mathematical models

    PubMed Central

    Li, Ya-jun; Zhao, Bao-lin; Lv, Hao-ze; Qin, Zhi-gang; Luo, Min

    2016-01-01

    We hypothesized that a chemically extracted acellular allogeneic nerve graft used in combination with bone marrow mesenchymal stem cell transplantation would be an effective treatment for long-segment sciatic nerve defects. To test this, we established rabbit models of 30 mm sciatic nerve defects, and treated them using either an autograft or a chemically decellularized allogeneic nerve graft with or without simultaneous transplantation of bone marrow mesenchymal stem cells. We compared the tensile properties, electrophysiological function and morphology of the damaged nerve in each group. Sciatic nerves repaired by the allogeneic nerve graft combined with stem cell transplantation showed better recovery than those repaired by the acellular allogeneic nerve graft alone, and produced similar results to those observed with the autograft. These findings confirm that a chemically extracted acellular allogeneic nerve graft combined with transplantation of bone marrow mesenchymal stem cells is an effective method of repairing long-segment sciatic nerve defects.

  3. 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

  4. Acellular Nerve Allografts in Peripheral Nerve Regeneration: A Comparative Study

    PubMed Central

    Moore, Amy M.; MacEwan, Matthew; Santosa, Katherine B.; Chenard, Kristofer E.; Ray, Wilson Z.; Hunter, Daniel A.; Mackinnon, Susan E.; Johnson, Philip J.

    2011-01-01

    Background Processed nerve allografts offer a promising alternative to nerve autografts in the surgical management of peripheral nerve injuries where short deficits exist. Methods Three established models of acellular nerve allograft (cold-preserved, detergent-processed, and AxoGen® -processed nerve allografts) were compared to nerve isografts and silicone nerve guidance conduits in a 14 mm rat sciatic nerve defect. Results All acellular nerve grafts were superior to silicone nerve conduits in support of nerve regeneration. Detergent-processed allografts were similar to isografts at 6 weeks post-operatively, while AxoGen®-processed and cold-preserved allografts supported significantly fewer regenerating nerve fibers. Measurement of muscle force confirmed that detergent-processed allografts promoted isograft-equivalent levels of motor recovery 16 weeks post-operatively. All acellular allografts promoted greater amounts of motor recovery compared to silicone conduits. Conclusions These findings provide evidence that differential processing for removal of cellular constituents in preparing acellular nerve allografts affects recovery in vivo. PMID:21660979

  5. Preclinical evaluations of acellular biological conduits for peripheral nerve regeneration

    PubMed Central

    Liao, I-Chien; Wan, Hua; Qi, Shijie; Cui, Cunqi; Patel, Paarun; Sun, Wendell

    2013-01-01

    Various types of natural biological conduits have been investigated as alternatives to the current surgical standard approach for peripheral nerve injuries. Autologous nerve graft, the current gold standard for peripheral nerve damage, is limited by clinical challenges such as donor-site morbidity and limited availability. The purpose of this study was to evaluate the efficacy of using acellular xenographic conduits (nerve, artery, and dermis) for the repair of a 1.2 cm critical size defect of peripheral nerve in a rodent model. Four months post surgery, the animal group receiving acellular artery as a nerve conduit showed excellent physiological outcome in terms of the prevention of muscle atrophy and foot ulcer. Histological assessment of the bridged site revealed excellent axon regeneration, as opposed to the nonrepaired control group or the group receiving dermal conduit. Finally, the study evaluated the potential improvement via the addition of undifferentiated mesenchymal stem cells into the artery conduit during the bridging procedure. The mesenchymal stem cell–dosed artery conduit group resulted in significantly higher concentration of regenerated axons over artery conduit alone, and exhibited accelerated muscle atrophy rescue. Our results demonstrated that xenographic artery conduits promoted excellent axonal regeneration with highly promising clinical relevance. PMID:23532671

  6. Adjuvant neurotrophic factors in peripheral nerve repair with chondroitin sulfate proteoglycan-reduced acellular nerve allografts

    PubMed Central

    Boyer, Richard B.; Sexton, Kevin W.; Rodriguez-Feo, Charles L.; Nookala, Ratnam; Pollins, Alonda C.; Cardwell, Nancy L.; Tisdale, Keonna Y.; Nanney, Lillian B.; Shack, R. Bruce; Thayer, Wesley P.

    2014-01-01

    count (P < 0.01), while significantly reducing IB4+ nociceptor axon count (P < 0.01). There were no significant differences produced by in vivo adjuvant GDNF. Conclusions This study provides initial evidence that CSPG-reduced nerve grafts may disinhibit the pro-survival effects of NGF in vivo, promoting motor axon outgrowth and reducing regeneration of specific nociceptive neurons. Our results support further investigation of adjuvant NGF therapy in CSPG-reduced acellular nerve grafts. PMID:25438961

  7. The Cellular Immune Mechanism after Transfer of Chemically Extracted Acellular Nerve Xenografts

    PubMed Central

    Lin, Xingshi; Yang, Ruojia; He, Qing; Ruan, Dike

    2013-01-01

    Severe peripheral nerve defect by injuries causing functional loss require nerve grafting. Autograft has limitations for clinical use because it results in the creation of a new nerve injury and the generation of donor site morbidity. Based on these limitations, nerve allografts and xenografts provide a readily accessible alternative strategy. The aim of the present study was to observe the immune mechanism underlying the rejection of chemically extracted acellular nerve xenografts, and further evaluate immunogenicity of chemically treated acellular nerve grafts for clinical applications. A total of 160 BALB/c mice were randomly divided into a negative contrast group (NC, 40 mice), a fresh autograft group (AG, 40 mice), a fresh xenogeneic nerve group (FXN, 40 mice) and a chemically extracted acellular xenogeneic nerve group (CEXN, 40 mice). Various types of nerve grafts were implanted into the thigh muscle of BALB/C mice in the corresponding groups. At 3, 7, 14 and 28 days post-operation, the mice (10 mice from each group) were sacrificed and their spleens were extracted. The spleens were ground into paste. The erythrocytes and other cells were lysed using distilled water and the T lymphocytes were collected. Fluorescein isothiocyanate (FITC) -labeled monoclonal antibodies (CD3, CD4, CD8, CD25, IL-2, IFN-γ and TNF-α) were then added to the solution. The Fluorescence Activated Cell Sorting (FACS) was used to determine the positivity rate of the cells combined with the monoclonal antibodies above. No significant statistical differences were observed between the CEXN, NC and AG groups, so that no obvious immune rejections were observed among the chemically extracted acellular nerve xenografts. PMID:23874771

  8. 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

  9. One-stage human acellular nerve allograft reconstruction for digital nerve defects

    PubMed Central

    Li, Xue-yuan; Hu, Hao-liang; Fei, Jian-rong; Wang, Xin; Wang, Tian-bing; Zhang, Pei-xun; Chen, Hong

    2015-01-01

    Human acellular nerve allografts have a wide range of donor origin and can effectively avoid nerve injury in the donor area. Very little is known about one-stage reconstruction of digital nerve defects. The present study observed the feasibility and effectiveness of human acellular nerve allograft in the reconstruction of < 5-cm digital nerve defects within 6 hours after injury. A total of 15 cases of nerve injury, combined with nerve defects in 18 digits from the Department of Emergency were enrolled in this study. After debridement, digital nerves were reconstructed using human acellular nerve allografts. The patients were followed up for 6–24 months after reconstruction. Mackinnon-Dellon static two-point discrimination results showed excellent and good rates of 89%. Semmes-Weinstein monofilament test demonstrated that light touch was normal, with an obvious improvement rate of 78%. These findings confirmed that human acellular nerve allograft for one-stage reconstruction of digital nerve defect after hand injury is feasible, which provides a novel trend for peripheral nerve reconstruction. PMID:25788927

  10. 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

  11. 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.

  12. 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

  13. BIOCOMPATIBILITY OF ACELLULAR DERMAL MATRIX GRAFT EVALUATED IN CULTURE OF MURINE MACROPHAGES

    PubMed Central

    Vendramini, Ana Paula; Melo, Rafaela Fernanda; Marcantonio, Rosemary Adriana Chiérici; Carlos, Iracilda Zepone

    2006-01-01

    The acellular dermal matrix allograft has been used as an alternative to autogenous palatal mucosal graft. The aim of this study was the evaluation of the biocompatibility of an acellular dermal matrix (AlloDerm®) in culture of macrophages. For hydrogen peroxidase determination we used the method of Pick & Kesari, and the Griess method for nitric oxide determination,. Statistical analysis showed no significant difference (p ≤ 0,05) in the release of nitric oxide and hydrogen peroxide by the macrophages exposed to acellular dermal matrix and the negative control. The results suggest that acellular dermal matrix did not activate the cell inflammatory response. PMID:19089033

  14. Molecular examination of bone marrow stromal cells and chondroitinase ABC-assisted acellular nerve allograft for peripheral nerve regeneration

    PubMed Central

    Wang, Ying; Jia, Hua; Li, Wen-Yuan; Guan, Li-Xin; Deng, Lingxiao; Liu, Yan-Cui; Liu, Gui-Bo

    2016-01-01

    The present study aimed to evaluate the molecular mechanisms underlying combinatorial bone marrow stromal cell (BMSC) transplantation and chondroitinase ABC (Ch-ABC) therapy in a model of acellular nerve allograft (ANA) repair of the sciatic nerve gap in rats. Sprague Dawley rats (n=24) were used as nerve donors and Wistar rats (n=48) were randomly divided into the following groups: Group I, Dulbecco's modified Eagle's medium (DMEM) control group (ANA treated with DMEM only); Group II, Ch-ABC group (ANA treated with Ch-ABC only); Group III, BMSC group (ANA seeded with BMSCs only); Group IV, Ch-ABC + BMSCs group (Ch-ABC treated ANA then seeded with BMSCs). After 8 weeks, the expression of nerve growth factor, brain-derived neurotrophic factor and vascular endothelial growth factor in the regenerated tissues were detected by reverse transcription-quantitative polymerase chain reaction and immunohistochemistry. Axonal regeneration, motor neuron protection and functional recovery were examined by immunohistochemistry, horseradish peroxidase retrograde neural tracing and electrophysiological and tibialis anterior muscle recovery analyses. It was observed that combination therapy enhances the growth response of the donor nerve locally as well as distally, at the level of the spinal cord motoneuron and the target muscle organ. This phenomenon is likely due to the propagation of retrograde and anterograde transport of growth signals sourced from the graft site. Collectively, growth improvement on the donor nerve, target muscle and motoneuron ultimately contribute to efficacious axonal regeneration and functional recovery. Thorough investigation of molecular peripheral nerve injury combinatorial strategies are required for the optimization of efficacious therapy and full functional recovery following ANA. PMID:27698684

  15. Molecular examination of bone marrow stromal cells and chondroitinase ABC-assisted acellular nerve allograft for peripheral nerve regeneration

    PubMed Central

    Wang, Ying; Jia, Hua; Li, Wen-Yuan; Guan, Li-Xin; Deng, Lingxiao; Liu, Yan-Cui; Liu, Gui-Bo

    2016-01-01

    The present study aimed to evaluate the molecular mechanisms underlying combinatorial bone marrow stromal cell (BMSC) transplantation and chondroitinase ABC (Ch-ABC) therapy in a model of acellular nerve allograft (ANA) repair of the sciatic nerve gap in rats. Sprague Dawley rats (n=24) were used as nerve donors and Wistar rats (n=48) were randomly divided into the following groups: Group I, Dulbecco's modified Eagle's medium (DMEM) control group (ANA treated with DMEM only); Group II, Ch-ABC group (ANA treated with Ch-ABC only); Group III, BMSC group (ANA seeded with BMSCs only); Group IV, Ch-ABC + BMSCs group (Ch-ABC treated ANA then seeded with BMSCs). After 8 weeks, the expression of nerve growth factor, brain-derived neurotrophic factor and vascular endothelial growth factor in the regenerated tissues were detected by reverse transcription-quantitative polymerase chain reaction and immunohistochemistry. Axonal regeneration, motor neuron protection and functional recovery were examined by immunohistochemistry, horseradish peroxidase retrograde neural tracing and electrophysiological and tibialis anterior muscle recovery analyses. It was observed that combination therapy enhances the growth response of the donor nerve locally as well as distally, at the level of the spinal cord motoneuron and the target muscle organ. This phenomenon is likely due to the propagation of retrograde and anterograde transport of growth signals sourced from the graft site. Collectively, growth improvement on the donor nerve, target muscle and motoneuron ultimately contribute to efficacious axonal regeneration and functional recovery. Thorough investigation of molecular peripheral nerve injury combinatorial strategies are required for the optimization of efficacious therapy and full functional recovery following ANA.

  16. Tissue engineering of the small intestine by acellular collagen sponge scaffold grafting.

    PubMed

    Hori, Y; Nakamura, T; Matsumoto, K; Kurokawa, Y; Satomi, S; Shimizu, Y

    2001-01-01

    Tissue engineering of the small intestine will prove a great benefit to patients suffering from short bowel disease. However cell seeding in tissue engineering, such as fetal cell use, is accompanied by problems of ethical issues, rejection, and short supply. To overcome these problems, we carried out an experimental study on tissue engineering of the small intestine by acellular collagen sponge scaffold grafting. We resected the 5 cm long jejunum from beagle dogs and reconstructed it by acellular collagen sponge grafting with a silicon tube stent. The graft was covered with the omentum. At 1 month after operation, the silicon stent was removed endoscopically. Animals were sacrificed 1 and 4 months after operation, and were examined microscopically. Neo-intestinal regeneration was observed and the intestinal mucosa covered the luminal side of the regenerated intestine across the anastomosis. Thus, the small intestine was regenerated by tissue engineering technology using an acellular collagen sponge scaffold.

  17. 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

  18. 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

  19. Nerve repair and cable grafting for facial paralysis.

    PubMed

    Humphrey, Clinton D; Kriet, J David

    2008-05-01

    Facial nerve injury and facial paralysis are devastating for patients. Although imperfect, primary repair is currently the best option to restore facial nerve function. Cable, or interposition, nerve grafting is an acceptable alternative when primary repair is not possible. Several donor nerves are at the surgeon's disposal. Great auricular, sural, or medial and lateral antebrachial cutaneous nerves are all easily obtained. Both primary repair and interposition grafting typically result in better facial function than do other dynamic and static rehabilitation strategies. Proficient anastomotic technique and, when necessary, selection of an appropriate interposition graft will optimize patient outcomes. Promising research is under way that will enhance future nerve repair and grafting efforts.

  20. 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

  1. Peripheral nerve explants grafted into the vitreous body of the eye promote the regeneration of retinal ganglion cell axons severed in the optic nerve.

    PubMed

    Berry, M; Carlile, J; Hunter, A

    1996-02-01

    We have conducted experiments in the adult rat visual system to assess the relative importance of an absence of trophic factors versus the presence of putative growth inhibitory molecules for the failure of regeneration of CNS axons after injury. The experiments comprised three groups of animals in which all optic nerves were crushed intra-orbitally: an optic nerve crush group had a sham implant-operation on the eye; the other two groups had peripheral nerve tissue introduced into the vitreous body; in an acellular peripheral nerve group, a frozen/thawed teased sciatic nerve segment was grafted, and in a cellular peripheral nerve group, a predegenerate teased segment of sciatic nerve was implanted. The rats were left for 20 days and their optic nerves and retinae prepared for immunohistochemical examination of both the reaction to injury of axons and glia in the nerve and also the viability of Schwann cells in the grafts. Anterograde axon tracing with rhodamine-B provided unequivocal qualitative evidence of regeneration in each group, and retrograde HRP tracing gave a measure of the numbers of axons growing across the lesion by counting HRP filled retinal ganglion cells in retinal whole mounts after HRP injection into the optic nerve distal to the lesion. No fibres crossed the lesion in the optic nerve crush group and dense scar tissue was formed in the wound site. GAP-43-positive and rhodamine-B filled axons in the acellular peripheral nerve and cellular peripheral nerve groups traversed the lesion and grew distally. There were greater numbers of regenerating fibres in the cellular peripheral nerve compared to the acellular peripheral nerve group. In the former, 0.6-10% of the retinal ganglion cell population regenerated axons at least 3-4 mm into the distal segment. In both the acellular peripheral nerve and cellular peripheral nerve groups, no basal lamina was deposited in the wound. Thus, although astrocyte processes were stacked around the lesion edge, a glia

  2. 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

  3. 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.

  4. 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

  5. Cross-Face Nerve Grafting with Infraorbital Nerve Pathway Protection: Anatomic and Histomorphometric Feasibility Study

    PubMed Central

    Catapano, Joseph; Demsey, Daniel R.B.; Ho, Emily S.; Zuker, Ronald M.

    2016-01-01

    Smiling is an important aspect of emotional expression and social interaction, leaving facial palsy patients with impaired social functioning and decreased overall quality of life. Although there are several techniques available for facial reanimation, staged facial reanimation using donor nerve branches from the contralateral, functioning facial nerve connected to a cross-face nerve graft (CFNG) is the only technique that can reliably reproduce an emotionally spontaneous smile. Although CFNGs provide spontaneity, they typically produce less smile excursion than when the subsequent free functioning muscle flap is innervated with the motor nerve to the masseter muscle. This may be explained in part by the larger number of donor motor axons when using the masseter nerve, as studies have shown that only 20% to 50% of facial nerve donor axons successfully cross the nerve graft to innervate their targets. As demonstrated in our animal studies, increasing the number of donor axons that grow into and traverse the CFNG to innervate the free muscle transfer increases muscle movement, and this phenomenon may provide patients with the benefit of improved smile excursion. We have previously shown in animal studies that sensory nerves, when coapted to a nerve graft, improve axonal growth through the nerve graft and improve muscle excursion. Here, we describe the feasibility of and our experience in translating these results clinically by coapting the distal portion of the CFNG to branches of the infraorbital nerve. PMID:27757349

  6. Differentiation of mesenchymal stem cells into neuronal cells on fetal bovine acellular dermal matrix as a tissue engineered nerve scaffold.

    PubMed

    Feng, Yuping; Wang, Jiao; Ling, Shixin; Li, Zhuo; Li, Mingsheng; Li, Qiongyi; Ma, Zongren; Yu, Sijiu

    2014-11-15

    The purpose of this study was to assess fetal bovine acellular dermal matrix as a scaffold for supporting the differentiation of bone marrow mesenchymal stem cells into neural cells following induction with neural differentiation medium. We performed long-term, continuous observation of cell morphology, growth, differentiation, and neuronal development using several microscopy techniques in conjunction with immunohistochemistry. We examined specific neuronal proteins and Nissl bodies involved in the differentiation process in order to determine the neuronal differentiation of bone marrow mesenchymal stem cells. The results show that bone marrow mesenchymal stem cells that differentiate on fetal bovine acellular dermal matrix display neuronal morphology with unipolar and bi/multipolar neurite elongations that express neuronal-specific proteins, including βIII tubulin. The bone marrow mesenchymal stem cells grown on fetal bovine acellular dermal matrix and induced for long periods of time with neural differentiation medium differentiated into a multilayered neural network-like structure with long nerve fibers that was composed of several parallel microfibers and neuronal cells, forming a complete neural circuit with dendrite-dendrite to axon-dendrite to dendrite-axon synapses. In addition, growth cones with filopodia were observed using scanning electron microscopy. Paraffin sectioning showed differentiated bone marrow mesenchymal stem cells with the typical features of neuronal phenotype, such as a large, round nucleus and a cytoplasm full of Nissl bodies. The data suggest that the biological scaffold fetal bovine acellular dermal matrix is capable of supporting human bone marrow mesenchymal stem cell differentiation into functional neurons and the subsequent formation of tissue engineered nerve.

  7. 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

  8. Comparison of nerve, vessel, and cartilage grafts in promoting peripheral nerve regeneration.

    PubMed

    Firat, Cemal; Geyik, Ylmaz; Aytekin, Ahmet Hamdi; Gül, Mehmet; Kamşl, Suat; Yiğitcan, Birgül; Ozcan, Cemal

    2014-07-01

    Peripheral nerve injury primarily occurs due to trauma as well as factors such as tumors, inflammatory diseases, congenital deformities, infections, and surgical interventions. The surgical procedure to be performed as treatment depends on the etiology, type of injury, and the anatomic region. The goal of treatment is to minimize loss of function due to motor and sensory nerve loss at the distal part of the injury. Regardless of the cause of the injury, the abnormal nerve regeneration due to incomplete nerve regeneration, optimal treatment of peripheral nerve injuries should provide adequate coaptation of proximal and distal sides without tension, preserving the neurotrophic factors within the repair line. The gold standard for the treatment of nerve defects is the autograft; however, due to denervation of the donor site, scarring, and neuroma formation, many studies have aimed to develop simpler methods, better functional results, and less morbidity. In this study, a defect 1 cm in length was created on the sciatic nerve of rats. The rats were treated with the following procedures: group 1, autograft; group 2, allogeneic aorta graft; group 3, diced cartilage graft in allogeneic aorta graft; and group 4, tubularized cartilage graft in allogeneic aorta graft. Group 5 was the control group. The effects of cartilage tissue in nerve regeneration were evaluated by functional and histomorphological methods.Group 1, for which the repair was performed with an autograft, was evaluated to be the most similar to the control group. There was not a statistically significant difference in myelination and Schwann cell rates between group 2, in which an allogeneic aorta graft was used, and group 3, in which diced cartilage in an allogeneic aorta graft was used. In group 4, myelination and Schwann cell formation were observed; however, they were scattered and irregular, likely due to increased fibrosis.In all of the groups, nerve regeneration at various rates was observed both

  9. Angiogenic response induced by acellular brain scaffolds grafted onto the chick embryo chorioallantoic membrane.

    PubMed

    Ribatti, Domenico; Conconi, Maria Teresa; Nico, Beatrice; Baiguera, Silvia; Corsi, Patrizia; Parnigotto, Pier Paolo; Nussdorfer, Gastone G

    2003-10-31

    The repair and regeneration of injured tissues and organs depend on the re-establishment of the blood flow needed for cellular infiltration and metabolic support. Among the various materials used in tissue reconstruction, acellular scaffolds have recently been utilized. In this study, we investigated the angiogenic response induced by acellular brain scaffolds implanted in vivo onto the chick embryo chorioallantoic membrane (CAM), a useful model for such investigations. The results show that acellular brain scaffolds are able to induce a strong angiogenic response, comparable to that of fibroblast growth factor-2 (FGF-2), a well known angiogenic cytokine. The response may be considered dependent on a direct angiogenic effect exerted by the scaffold, because no inflammatory infiltrate was detectable in CAM's mesenchyme beneath the implant. Acellular brain scaffolds might induce the release of endogenous angiogenic factors, such as FGF-2 and vascular endothelial growth factor (VEGF) released from the extracellular matrix of the developing CAM. In addition, the angiogenic response may depend, in part, also on the presence in the acellular matrix of transforming growth factor beta 1 (TGFbeta1).

  10. Successful obturator nerve repairing: Intraoperative sural nerve graft harvesting in endometrium cancer patient

    PubMed Central

    Harma, Müge; Sel, Görker; Açıkgöz, Bektaş; Harma, Mehmet İbrahim

    2014-01-01

    INTRODUCTION Intraoperative injury of obturator nerve is a rare complication of gynecologic surgeries, it has been reported especially in patients with endometriosis and genitourinary malignancies. Gynecologic patients undergoing open lymphadenectomy are at increased risk of obturator nerve injury. PRESENTATION OF CASE A 60-year-old woman with FIGO stage II Grade II endometrial adenocarcinoma underwent bilateral pelvic paraaortic lymphadenectomy. During right obturator lymph node dissection, the right obturator nerve was inadvertently transected with Harmonic scalpel sealing system. The graft was used to anastomose epyneurium of distal segment of obturator nerve to its counterpart in the proximal segment with 10–0 prolen suture. DISCUSSION In case of iatrogenic nerve transection, microsurgical end to end tension-free coaptation is advocated. In case of the obturator nerve is fixed and because of the thermal injury end to end alignment can not be achieved, nerve grafting is necessary. CONCLUSION According to our knowledge, successful immediate grafting of iatrogenically damaged obturator nerve during pelvic lymphadenectomy in our patient is the third report of such a case, but also it has a unique feature of being the first obturator nerve repairing case after dissected with tissue sealing system which causes large sealed area that does not make it possible to make end-to-end anastomosis without nerve harvesting. PMID:24814984

  11. The influence of predegenerated nerve grafts on axonal regeneration from prelesioned peripheral nerves.

    PubMed Central

    Hasan, N A; Neumann, M M; de Souky, M A; So, K F; Bedi, K S

    1996-01-01

    Recent in vitro work has indicated that predegenerated segments of peripheral nerve are more capable of supporting neurite growth from adult neurons than fresh segments of nerve, whereas previous in vivo studies which investigated whether predegenerated nerve segments used as grafts are capable of enhancing axonal regeneration produced conflicting results. We have reinvestigated this question by using predegenerated nerve grafts in combination with conditioning lesions of the host nerve to determine the optimal conditions for obtaining the maximal degree of regeneration of myelinated axons. The sciatic nerve of adult Dark Agouti rats were sectioned at midthigh level, and the distal portion was allowed to predegenerate for 0, 6 or 12 d in situ. 10-15 mm lengths of these distal nerve segments were then syngenically grafted onto the central stumps of sciatic nerves which had themselves received a conditioning lesion 0, 6, and 12 d previously, making a total of 9 different donor-host combinations. The grafts were assessed histologically 3 or 8 wk after grafting. Axonal regeneration in the 9 different donor-host combinations was determined by counting the numbers of myelinated axons in transverse sections through the grafts. All grafts examined contained regenerating myelinated axons. The rats given a 3 wk postgrafting survival period had an average of between 1400 and 5300 such axons. The rats given an 8 wk postgrafting survival period had between about 13,000 and 25,000 regenerating myelinated axons. Analysis of variance revealed significant main effects for both the Donor and Host conditions as well as Weeks (i.e. survival period after grafting). These results indicate that both a conditioning lesion of the host neurons and the degree of predegeneration of peripheral nerve segments to be used as grafts are of importance in influencing the degree of axonal regeneration. Of these 2 factors the conditioning lesion of the host appears to have the greater effect on the

  12. 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

  13. 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

  14. Aged adrenal medullary tissue survives intraocular grafting, forms nerve fibers and responds to nerve growth factor.

    PubMed

    Strömberg, I; Ebendal, T

    1989-06-01

    Adrenal medullary tissue from aged (24 months old) and young adult (2 months old) rats was grafted to the anterior chamber of the eye of previously sympathectomized animals. Nerve growth factor (NGF) was administered by weekly bilateral intraocular injections. Five weeks postgrafting, irides were prepared as whole mounts and processed for Falck-Hillarp histochemistry for visualization of catecholamines. NGF appeared to partially prevent the reduction in volume that both old and young grafts underwent. In the presence of NGF, an extensive, dense fiber network, closely resembling the normal adrenergic innervation, was formed in the host irides by grafts from aged donors. The area of outgrowth from aged transplants without NGF treatment was as large as with NGF treatment but less dense. The reinnervation of irides by NGF-treated young adult grafts occupied a similar area as that seen with aged grafts, but the pattern of innervation was irregular, particularly close to the transplants. Transplants from young adult donors without NGF treatment generated a sparse, limited network of nerves in the irides. All grafts were tyrosine hydroxylase-, adrenaline-, and dopamine-beta-hydroxylase-immunoreactive in about the same proportion of cells, but the grafts from the young donors were smaller in size. We concluded that the ability of chromaffin cells to transform toward a neuronal phenotype, produce nerve fibers, and respond to exogenous NGF is maintained in aged adrenals. PMID:2754763

  15. Tissue engineering of acellular vascular grafts capable of somatic growth in young lambs

    PubMed Central

    Syedain, Zeeshan; Reimer, Jay; Lahti, Matthew; Berry, James; Johnson, Sandra; Tranquillo, Robert T.

    2016-01-01

    Treatment of congenital heart defects in children requiring right ventricular outflow tract reconstruction typically involves multiple open-heart surgeries because all existing graft materials have no growth potential. Here we present an ‘off-the-shelf' vascular graft grown from donor fibroblasts in a fibrin gel to address this critical unmet need. In a proof-of-concept study, the decellularized grafts are implanted as a pulmonary artery replacement in three young lambs and evaluated to adulthood. Longitudinal ultrasounds document dimensional growth of the grafts. The lambs show normal growth, increasing body weight by 366% and graft diameter and volume by 56% and 216%, respectively. Explanted grafts display physiological strength and stiffness, complete lumen endothelialization and extensive population by mature smooth muscle cells. The grafts also show substantial elastin deposition and a 465% increase in collagen content, without signs of calcification, aneurysm or stenosis. Collectively, our data support somatic growth of this completely biological graft. PMID:27676438

  16. Differential Reanimation of the Upper and Lower Face Using 2 Interpositional Nerve Grafts in Total Facial Nerve Reconstruction

    PubMed Central

    Nishibayashi, Akimitsu; Yano, Kenji; Hosokawa, Ko

    2015-01-01

    Summary: Radical parotidectomy often results in complex facial nerve defects involving the main nerve trunk and multiple distal nerve branches. Although cable nerve grafting often leads to good nerve regeneration, severe synkinesis due to aberrant axonal regrowth is inevitable. In such situations, the use of 2 motor sources to differentially reanimate the upper and lower face could minimize synkinesis. Here we describe a method of total facial nerve reconstruction in which the upper and lower face are differentially reconstructed with the hypoglossal nerve and facial nerve, respectively, using 2 interpositional nerve grafts. Reconstruction of the lower face with the facial nerve restored voluntary and coordinated animation, and reconstruction of the upper face with the hypoglossal nerve restored frontalis muscle tone and eye closure. These results suggest that our method could serve as an alternative to conventional techniques that use only the facial or hypoglossal nerve. PMID:26579350

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

    PubMed

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

    2013-12-01

    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

  18. 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

  19. 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

  20. Agmatine treatment and vein graft reconstruction enhance recovery after experimental facial nerve injury.

    PubMed

    Berenholz, Leonard; Segal, Shmuel; Gilad, Varda H; Klein, Collen; Yehezkeli, Eyal; Eviatar, Ephraim; Kessler, Alex; Gilad, Gad M

    2005-09-01

    The rate of nerve regeneration is a critical determinant of the degree of functional recovery after injury. Here, we sought to determine whether treatment with the neuroprotective compound, agmatine, with or without nerve reconstruction utilizing a regional autogenous vein graft would accelerate the rate of facial nerve regeneration. Experiments compared the following seven groups of adult male rats: (A) Intact untreated controls. (B) Sham operation with interruption of the nerve blood supply (controls). (C) Transection of the mandibular branch of the facial nerve (generating a gap of 3 mm) followed by saline treatment. (D) Nerve transection with unsutured autogenous vein (external jugular) graft reconstruction plus saline treatment. (E) Nerve transection with sutured vein graft approximation (coaptation of the proximal and distal nerve stumps) plus saline. (F) Nerve transection with sutured vein graft followed by agmatine treatment (four daily intraperitoneal injections of 100 mg/kg agmatine sulfate). (G) Nerve transection with unsutured vein graft followed by agmatine treatment. Functional recovery, as assessed by grading vibrissae movements and by recording nerve conduction velocity and numbers of regenerated axons, indicated that either vein reconstruction or agmatine treatment resulted in accelerated and more complete recovery as compared with controls. But best results were observed in animals that underwent combined treatment, i.e., vein reconstruction plus agmatine injection. We conclude that agmatine treatment can accelerate facial nerve regeneration and that agmatine treatment together with autogenous vein graft offers an advantageous alternative to other facial nerve reconstruction procedures.

  1. The Performance of Cross-linked Acellular Arterial Scaffolds as Vascular Grafts; Pre-clinical Testing in Direct and Isolation Loop Circulatory Models

    PubMed Central

    Pennel, Timothy; Fercana, George; Bezuidenhout, Deon; Simionescu, Agneta; Chuang, Ting-Hsien; Zilla, Peter; Simionescu, Dan

    2014-01-01

    There is a significant need for small diameter vascular grafts to be used in peripheral vascular surgery; however autologous grafts are not always available, synthetic grafts perform poorly and allografts and xenografts degenerate, dilate and calcify after implantation. We hypothesized that chemical stabilization of acellular xenogenic arteries would generate off-the-shelf grafts resistant to thrombosis, dilatation and calcification. To test this hypothesis, we decellularized porcine renal arteries, stabilized elastin with penta-galloyl glucose and collagen with carbodiimide / activated heparin and implanted them as transposition grafts in the abdominal aorta of rats as direct implants and separately as indirect, isolation-loop implants. All implants resulted in high patency and animal survival rates, ubiquitous encapsulation within a vascularized collagenous capsule, and exhibited lack of lumen thrombogenicity and no graft wall calcification. Peri-anastomotic neo-intimal tissue overgrowth was a normal occurrence in direct implants; however this reaction was circumvented in indirect implants. Notably, implantation of non-treated control scaffolds exhibited marked graft dilatation and elastin degeneration; however PGG significantly reduced elastin degradation and prevented aneurismal dilatation of vascular grafts. Overall these results point to the outstanding potential of crosslinked arterial scaffolds as small diameter vascular grafts. PMID:24816365

  2. A new type of Schwann cell graft transplantation to promote optic nerve regeneration in adult rats.

    PubMed

    Fang, Yuan; Mo, Xiaofen; Guo, Wenyi; Zhang, Meng; Zhang, Peihua; Wang, Yan; Rong, Xianfang; Tian, Jie; Sun, Xinghuai

    2010-12-01

    Like other parts of the central nervous system, the adult mammalian optic nerve is difficult to regenerate after injury. Transplantation of the peripheral nerve or a Schwann cell (SC) graft can promote injured axonal regrowth. We tried to develop a new type of tissue-engineered SC graft that consisted of SCs seeded onto a poly(lactic-co-glycolic acid)/chitosan conduit. Meanwhile, SCs were transfected along the ciliary neurotrophic factor (CNTF) gene in vitro by electroporation to increase their neurotrophic effect. Four weeks after transplantation, GAP-43 labelled regenerating axons were found in the SC grafts, and axons in the CNTF-SC graft were longer than those in the SC graft. Tissue-engineered SC grafts can provide a feasible environment for optic nerve regeneration and may become an alternative for bridging damaged nerves and repairing nerve defects in the future.

  3. Perineurial differentiation in interchange grafts of rat peripheral nerve and spinal root.

    PubMed Central

    Radek, A; Thomas, P K; King, R H

    1986-01-01

    The differentiation of the perineurium has been examined in replacement nerve grafts in which segments of the third lumbar dorsal root and the peroneal division of the sciatic nerve of rats were excised and resutured into the gaps. This was compared with perineurial differentiation in interchange grafts in which segments of peroneal nerve were grafted into the third lumbar dorsal root and vice versa. It was concluded that not only the origin of the graft but also the local tissue environment is important in determining the morphological outcome, the latter having the predominant influence. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 PMID:3693073

  4. A laminin-2-derived peptide promotes early-stage peripheral nerve regeneration in a dual-component artificial nerve graft.

    PubMed

    Seo, S Y; Min, S-K; Bae, H K; Roh, D; Kang, H K; Roh, S; Lee, S; Chun, G-S; Chung, D-J; Min, B-M

    2013-10-01

    The DLTIDDSYWYRI motif (Ln2-P3) of human laminin-2 has been reported to promote PC12 cell attachment through syndecan-1; however, the in vivo effects of Ln2-P3 have not been studied. In Schwann cells differentiated from skin-derived precursors, the peptide was effective in promoting cell attachment and spreading in vitro. To examine the effects of Ln2-P3 in peripheral nerve regeneration in vivo, we developed a dual-component poly(p-dioxanone) (PPD)/poly(lactic-co-glycolic acid) (PLGA) artificial nerve graft. The novel graft was coated with scrambled peptide or Ln2-P3 and used to bridge a 10 mm defect in rat sciatic nerves. The dual-component nerve grafts provided tensile strength comparable to that of a real rat nerve trunk. The Ln2-P3-treated grafts promoted early-stage peripheral nerve regeneration by enhancing the nerve regeneration rate and significantly increased the myelinated fibre density compared with scrambled peptide-treated controls. These findings indicate that Ln2-P3, combined with tissue-engineering scaffolds, has potential biomedical applications in peripheral nerve injury repair. PMID:22438104

  5. Wide resection of traction induced radial nerve injury with cable grafting leads to full recovery.

    PubMed

    Henry, Mark

    2006-12-01

    The specific clinical setting of high-energy open humerus fractures combined with radial nerve transection has typically led to poor final outcomes with respect to recovery of nerve function. Attention has focused on the issue of an expanded zone of nerve injury induced by longitudinal traction. The fundamental principle of nerve grafting is to bypass the zone of injury. If direct repair or short nerve grafts are placed within the zone of injury, limited recovery should be expected, and this is exactly what has been documented. Wide resection of the zone of traction induced injury, particularly from the distal injured nerve trunk and replacement with long cable grafts has the potential for improved outcomes. Complete nerve recovery to 5/5 manual motor power testing and bilaterally equivalent grip strength is reported in two initial cases treated according to the wide resection plan.

  6. Acellular human heart matrix: A critical step toward whole heart grafts.

    PubMed

    Sánchez, Pedro L; Fernández-Santos, M Eugenia; Costanza, Salvatore; Climent, Andreu M; Moscoso, Isabel; Gonzalez-Nicolas, M Angeles; Sanz-Ruiz, Ricardo; Rodríguez, Hugo; Kren, Stefan M; Garrido, Gregorio; Escalante, Jose L; Bermejo, Javier; Elizaga, Jaime; Menarguez, Javier; Yotti, Raquel; Pérez del Villar, Candelas; Espinosa, M Angeles; Guillem, María S; Willerson, James T; Bernad, Antonio; Matesanz, Rafael; Taylor, Doris A; Fernández-Avilés, Francisco

    2015-08-01

    The best definitive treatment option for end-stage heart failure currently is transplantation, which is limited by donor availability and immunorejection. Generating an autologous bioartificial heart could overcome these limitations. Here, we have decellularized a human heart, preserving its 3-dimensional architecture and vascularity, and recellularized the decellularized extracellular matrix (dECM). We decellularized 39 human hearts with sodium-dodecyl-sulfate for 4-8 days. Cell removal and architectural integrity were determined anatomically, functionally, and histologically. To assess cytocompatibility, we cultured human cardiac-progenitor cells (hCPC), bone-marrow mesenchymal cells (hMSCs), human endothelial cells (HUVECs), and H9c1 and HL-1 cardiomyocytes in vitro on dECM ventricles up to 21 days. Cell survival, gene expression, organization and/or electrical coupling were analyzed and compared to conventional 2-dimensional cultures. Decellularization removed cells but preserved the 3-dimensional cardiac macro and microstructure and the native vascular network in a perfusable state. Cell survival was observed on dECM for 21 days. hCPCs and hMSCs expressed cardiocyte genes but did not adopt cardiocyte morphology or organization; HUVECs formed a lining of endocardium and vasculature; differentiated cardiomyocytes organized into nascent muscle bundles and displayed mature calcium dynamics and electrical coupling in recellularized dECM. In summary, decellularization of human hearts provides a biocompatible scaffold that retains 3-dimensional architecture and vascularity and that can be recellularized with parenchymal and vascular cells. dECM promotes cardiocyte gene expression in stem cells and organizes existing cardiomyocytes into nascent muscle showing electrical coupling. These findings represent a first step toward manufacturing human heart grafts or matrix components for treating cardiovascular disease.

  7. Use of spider silk fibres as an innovative material in a biocompatible artificial nerve conduit.

    PubMed

    Allmeling, Christina; Jokuszies, Andreas; Reimers, Kerstin; Kall, Susanne; Vogt, Peter M

    2006-01-01

    Defects of peripheral nerves still represent a challenge for surgical nerve reconstruction. Recent studies concentrated on replacement by artificial nerve conduits from different synthetic or biological materials. In our study, we describe for the first time the use of spider silk fibres as a new material in nerve tissue engineering. Schwann cells (SC) were cultivated on spider silk fibres. Cells adhered quickly on the fibres compared to polydioxanone monofilaments (PDS). SC survival and proliferation was normal in Live/Dead assays. The silk fibres were ensheathed completely with cells. We developed composite nerve grafts of acellularized veins, spider silk fibres and SC diluted in matrigel. These artificial nerve grafts could be cultivated in vitro for one week. Histological analysis showed that the cells were vital and formed distinct columns along the silk fibres. In conclusion, our results show that artificial nerve grafts can be constructed successfully from spider silk, acellularized veins and SC mixed with matrigel. PMID:16989736

  8. 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

  9. 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

  10. 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

  11. 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.

  12. Ketoprofen combined with artery graft entubulization improves functional recovery of transected peripheral nerves.

    PubMed

    Mohammadi, Rahim; Mehrtash, Moein; Nikonam, Nima; Mehrtash, Moied; Amini, Keyvan

    2014-12-01

    The objective was to assess the local effect of ketoprofen on sciatic nerve regeneration and functional recovery. Eighty healthy male white Wistar rats were randomized into four experimental groups of 20 animals each: In the transected group (TC), the left sciatic nerve was transected and nerve cut ends were fixed in the adjacent muscle. In the treatment group the defect was bridged using an artery graft (AG/Keto) filled with 10 microliter ketoprofen (0.1 mg/kg). In the artery graft group (AG), the graft was filled with phosphated-buffer saline alone. In the sham-operated group (SHAM), the sciatic nerve was exposed and manipulated. Each group was subdivided into four subgroups of five animals each and regenerated nerve fibres were studied at 4, 8, 12 and 16 weeks post operation. Behavioural testing, sciatic nerve functional study, gastrocnemius muscle mass and morphometric indices showed earlier regeneration of axons in AG/Keto than in AG group (p < 0.05). Immunohistochemical study clearly showed more positive location of reactions to S-100 in AG/Keto than in AG group. When loaded in an artery graft, ketoprofen improved functional recovery and morphometric indices of the sciatic nerve. Local usage of this easily accessible therapeutic medicine is cost saving and avoids the problems associated with systemic administration.

  13. Peripheral Nerve Damage Facilitates Functional Innervation of Brain Grafts in Adult Sensory Cortex

    NASA Astrophysics Data System (ADS)

    Ebner, Ford F.; Erzurumlu, Reha S.; Lee, Stefan M.

    1989-01-01

    The neuralb pathways that relay information from cutaneous receptors to the cortex provide the somatic sensory information needed for cortical function. The last sensory relay neurons in this pathway have cell bodies in the thalamus and axons that synapse on neurons in the somatosensory cortex. After cortical lesions that damage mature thalamocortical fibers in the somatosensory cortex, we have attempted to reestablish somatosensory cortical function by grafting embryonic neocortical cells into the lesioned area. Such grafts survive in adult host animals but are not innervated by thalamic neurons, and consequently the grafted neurons show little if any spontaneous activity and no responses to cutaneous stimuli. We have reported that transection of peripheral sensory nerves prior to grafting ``conditions'' or ``primes'' the thalamic neurons in the ventrobasal complex so that they extend axons into grafts subsequently placed in the cortical domain of the cut nerve. In this report we present evidence that the ingrowth of ventrobasal fibers leads to graft neurons that become functionally integrated into the sensory circuitry of the host brain. Specifically, the conditioning lesions made prior to grafting produce graft neurons that are spontaneously active and can be driven by natural activation of cutaneous receptors or electrical stimulation of the transected nerve after it regenerates. Furthermore, oxidative metabolism in these grafts reaches levels that are comparable to normal cortex, whereas without prior nerve cut, oxidative metabolism is abnormally low in neocortical grafts. We conclude that damage to the sensory periphery transsynaptically stimulates reorganization of sensory pathways through mechanisms that include axonal elongation and functional synaptogenesis.

  14. 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

  15. Subjective outcome related to donor site morbidity after sural nerve graft harvesting: a survey in 41 patients

    PubMed Central

    2013-01-01

    Background The sural nerve is the most commonly used nerve for grafting severe nerve defects. Our aim was to evaluate subjective outcome in the lower leg after harvesting the sural nerve for grafting nerve defects. Methods Forty-six patients were asked to fill in a questionnaire to describe symptoms from leg or foot, where the sural nerve has been harvested to reconstruct an injured major nerve trunk. The questionnaire, previously used in patients going through a nerve biopsy, consists of questions about loss of sensation, pain, cold intolerance, allodynia and present problems from the foot. The survey also contained questions (visual analogue scales; VAS) about disability from the reconstructed nerve trunk. Results Forty-one out of 46 patients replied [35 males/6 females; age at reconstruction 23.0 years (10–72); median (min-max), reconstruction done 12 (1.2-39) years ago]. In most patients [37/41 cases (90%)], the sural nerve graft was used to reconstruct an injured nerve trunk in the upper extremity, mainly the median nerve [19/41 (46%)]. In 38/41 patients, loss of sensation, to a variable extent, in the skin area innervated by the sural nerve was noted. These problems persisted at follow up, but 19/41 noted that this area of sensory deficit had decreased over time. Few patients had pain and less than 1/3 had cold intolerance. Allodynia was present in half of the patients, but the majority of them considered that they had no or only slight problems from their foot. None of the patients in the study required painkillers. Eighty eight per cent would accept an additional sural nerve graft procedure if another nerve reconstruction procedure is necessary in the future. Conclusions Harvesting of the sural nerve for reconstruction nerve injuries results in mild residual symptoms similar to those seen after a nerve biopsy; although nerve biopsy patients are less prone to undergo an additional biopsy. PMID:24063721

  16. 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

  17. 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

  18. Repair of ocular-oral synkinesis of postfacial paralysis using cross-facial nerve grafting.

    PubMed

    Zhang, Bo; Yang, Chuan; Wang, Wei; Li, Wei

    2010-08-01

    We present the surgical techniques and results of cross-facial nerve grafting that have been developed in the repair of ocular-oral synkinesis after facial paralysis. Eleven patients with ocular-oral synkinesis after facial paralysis underwent the cross-facial nerve grafting with facial nerve transposition at a tertiary academic hospital between 2003 and 2009. The patient selection for the study was based on the degree of disfigurement and facial function parameter rating using the Toronto Facial Grading System. The procedures used were surgeries done in two stages. All cases were followed up for 2 months to 6 years after the second surgery. The degree of improvement was evaluated at 6 to 7 months after the procedures. Six of the patients were followed up for more than 2 years after the stage-two surgery and demonstrated significant reduction in the ocular-oral synkinetic movements. The Toronto Facial Grading System scores from the postoperative follow-ups increased an average of 16 points (28%), and the patients had achieved symmetrical facial movement. We concluded that cross-facial nerve grafting with facial nerve branch transposition is effective and can be considered as an option for the repair of ocular-oral synkinesis after facial paralysis in select patients.

  19. Promoting nerve cell functions on hydrogels grafted with poly(L-lysine).

    PubMed

    Cai, Lei; Lu, Jie; Sheen, Volney; Wang, Shanfeng

    2012-02-13

    We present a novel photopolymerizable poly(L-lysine) (PLL) and use it to modify polyethylene glycol diacrylate (PEGDA) hydrogels for creating a better, permissive nerve cell niche. Compared with their neutral counterparts, these PLL-grafted hydrogels greatly enhance pheochromocytoma (PC12) cell survival in encapsulation, proliferation, and neurite growth and also promote neural progenitor cell proliferation and differentiation capacity, represented by percentages of both differentiated neurons and astrocytes. The role of efficiently controlled substrate stiffness in regulating nerve cell behavior is also investigated and a polymerizable cationic small molecule, [2-(methacryloyloxy)ethyl]-trimethylammonium chloride (MTAC), is used to compare with this newly developed PLL. The results indicate that these PLL-grafted hydrogels are promising biomaterials for nerve repair and regeneration.

  20. Combining peripheral nerve grafts and chondroitinase promotes functional axonal regeneration in the chronically injured spinal cord.

    PubMed

    Tom, Veronica J; Sandrow-Feinberg, Harra R; Miller, Kassi; Santi, Lauren; Connors, Theresa; Lemay, Michel A; Houlé, John D

    2009-11-25

    Because there currently is no treatment for spinal cord injury, most patients are living with long-standing injuries. Therefore, strategies aimed at promoting restoration of function to the chronically injured spinal cord have high therapeutic value. For successful regeneration, long-injured axons must overcome their poor intrinsic growth potential as well as the inhibitory environment of the glial scar established around the lesion site. Acutely injured axons that regenerate into growth-permissive peripheral nerve grafts (PNGs) reenter host tissue to mediate functional recovery if the distal graft-host interface is treated with chondroitinase ABC (ChABC) to cleave inhibitory chondroitin sulfate proteoglycans in the scar matrix. To determine whether a similar strategy is effective for a chronic injury, we combined grafting of a peripheral nerve into a highly relevant, chronic, cervical contusion site with ChABC treatment of the glial scar and glial cell line-derived neurotrophic factor (GDNF) stimulation of long-injured axons. We tested this combination in two grafting paradigms: (1) a peripheral nerve that was grafted to span a chronic injury site or (2) a PNG that bridged a chronic contusion site with a second, more distal injury site. Unlike GDNF-PBS treatment, GDNF-ChABC treatment facilitated axons to exit the PNG into host tissue and promoted some functional recovery. Electrical stimulation of axons in the peripheral nerve bridge induced c-Fos expression in host neurons, indicative of synaptic contact by regenerating fibers. Thus, our data demonstrate, for the first time, that administering ChABC to a distal graft interface allows for functional axonal regeneration by chronically injured neurons.

  1. 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

  2. Combining Peripheral Nerve Grafts and Chondroitinase Promotes Functional Axonal Regeneration in the Chronically Injured Spinal Cord

    PubMed Central

    Tom, Veronica J.; Sandrow-Feinberg, Harra R.; Miller, Kassi; Santi, Lauren; Connors, Theresa; Lemay, Michel A.; Houlé, John D.

    2010-01-01

    Because there currently is no treatment for spinal cord injury, most patients are living with long-standing injuries. Therefore, strategies aimed at promoting restoration of function to the chronically injured spinal cord have high therapeutic value. For successful regeneration, long-injured axons must overcome their poor intrinsic growth potential as well as the inhibitory environment of the glial scar established around the lesion site. Acutely injured axons that regenerate into growth-permissive peripheral nerve grafts (PNGs) reenter host tissue to mediate functional recovery if the distal graft– host interface is treated with chondroitinase ABC (ChABC) to cleave inhibitory chondroitin sulfate proteoglycans in the scar matrix. To determine whether a similar strategy is effective for a chronic injury, we combined grafting of a peripheral nerve into a highly relevant, chronic, cervical contusion site with ChABC treatment of the glial scar and glial cell line-derived neurotrophic factor (GDNF) stimulation of long-injured axons. We tested this combination in two grafting paradigms: (1) a peripheral nerve that was grafted to span a chronic injury site or (2) a PNG that bridged a chronic contusion site with a second, more distal injury site. Unlike GDNF–PBS treatment, GDNF–ChABC treatment facilitated axons to exit the PNG into host tissue and promoted some functional recovery. Electrical stimulation of axons in the peripheral nerve bridge induced c-Fos expression in host neurons, indicative of synaptic contact by regenerating fibers. Thus, our data demonstrate, for the first time, that administering ChABC to a distal graft interface allows for functional axonal regeneration by chronically injured neurons. PMID:19940184

  3. Treatment of left laryngeal hemiplegia in standardbreds, using a nerve muscle pedicle graft.

    PubMed

    Fulton, I C; Derksen, F J; Stick, J A; Robinson, N E; Walshaw, R

    1991-09-01

    The efficacy of a nerve muscle pedicle (NMP) graft in restoring upper airway function was evaluated in exercising horses with induced left laryngeal hemiplegia. The NMP graft was created from the first cervical nerve and the omohyoideus muscle and transplanted into the left cricoarytenoideus dorsalis muscle. Seven adult Standardbreds were trained to exercise on a treadmill inclined at 6.38 degrees. With the horses at rest and exercising at 4.2 and 7.0 m/s, the following variables were recorded: peak inspiratory and expiratory transupper airway pressures (defined as the pressure difference between a lateral tracheal catheter and a mask catheter), peak inspiratory and expiratory air flow, inspiratory and expiratory impedance, tidal volume, minute ventilation, heart rate, and respiratory frequency. Measurements were made before left recurrent laryngeal neurectomy (LRLN), 28 days after LRLN, and 12, 24, and 52 weeks after the NMP graft (n = 5) or sham operation (n = 2). Before LRLN, exercise increased inspiratory and expiratory air flow and transupper airway pressure, whereas the impedance was unchanged. After LRLN, transupper airway inspiratory pressure and impedance were significantly greater and inspiratory air flow was significantly less than baseline values at 7.0 m/s. The sham operation did not improve airway function. Twelve weeks after insertion of the NMP graft, inspiratory impedance and inspiratory air flow were significantly different (improved) from LRLN values. Twenty-four weeks after insertion of the NMP graft, inspiratory impedance was not significantly different from LRLN values.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. 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

  5. Reanimation of reversible facial paralysis by the double innervation technique using an intraneural-dissected sural nerve graft.

    PubMed

    Tomita, Koichi; Hosokawa, Ko; Yano, Kenji

    2010-06-01

    In treating reversible facial paralysis, cross-facial nerve grafting offers voluntary and emotional reanimation. In contrast, rapid re-innervation and strong neural stimulation can be obtained with hypoglossal-facial nerve crossover. In this article, we describe the method of a combination of these techniques as a one-stage procedure. A 39-year-old man presented with facial paralysis due to nerve avulsion within the stylomastoid foramen. The sural nerve was harvested and two branches were created at its distal end by intraneural dissection. One branch was anastomosed to the contralateral facial nerve, and the other branch was used for hypoglossal-facial nerve crossover, followed by connecting the proximal stump of the graft to the trunk of the paralysed facial nerve in an end-to-end fashion. At 9 months postoperatively, almost complete facial symmetry and co-ordinated movements of the mimetic muscles were obtained with no obvious tongue atrophy. Since our method can efficiently gather neural inputs from the contralateral facial nerve and the ipsilateral hypoglossal nerve, it may become a good alternative for reanimation of reversible facial paralysis when the ipsilateral facial nerve is not available.

  6. Histologic evaluation of nerve muscle pedicle graft used as a treatment for left laryngeal hemiplegia in standardbreds.

    PubMed

    Fulton, I C; Derksen, F J; Stick, J A; Robinson, N E; Duncan, I D

    1992-04-01

    A nerve muscle pedicle (NMP) graft was placed in the cricoarytenoideus dorsalis (CAD) muscle of 6 horses with induced left laryngeal hemiplegia. The NMP graft was created by use of the first cervical nerve and omohyoideus muscle. In 1 horse (control), the first cervical nerve was transected after placement of the NMP graft. One year after the surgical procedure, horses were examined endoscopically and then anesthetized. While the larynx was observed endoscopically, the first cervical nerve was stimulated. Horses were subsequently euthanatized, and the larynx was harvested. Prior to anesthesia, the endoscopic appearance of the larynx of all horses was typical of laryngeal hemiplegia. During anesthesia, stimulation of the first cervical nerve produced vigorous abduction of the left arytenoid in principal horses but not in the control horse. The right cricoarytenoideus lateralis and CAD muscles were grossly and histologically normal. Also, the left cricoarytenoideus lateralis was atrophic in all horses as was the left CAD muscle of the control horse. In contrast, the left CAD muscle harvested from principal horses had evidence of reinnervation with type 1 or type 2 fiber grouping. One year after the NMP graft procedure, horses with left laryngeal hemiplegia had reinnervation of the left CAD muscle. In another study, reinnervation was sufficient to allow normal laryngeal function during exercise. Combined, these data suggest that the NMP graft procedure is a viable technique for the treatment of left laryngeal hemiplegia in horses.

  7. An endoscopic approach to longitudinal structures including muscle flaps and vein, tendon, and nerve grafts.

    PubMed

    Hallock, Geoffrey G; Rice, David C

    2008-02-01

    Anatomically favorable structures that have a longitudinal orientation are particularly amenable to endoscopic harvest. Typically, only a single portal is necessary for access, and an optical cavity can be maintained using a mechanical retraction device. As with all minimal invasive surgery, this can still allow rapid and often a safer tissue harvest with diminished morbidity, especially with respect to wound healing and non-aesthetic scar formation. Many plastic surgery applications have already been described facilitated by the endoscopic harvest of vein, tendon, and nerve grafts, as well as certain local or free muscle flaps.

  8. Inside-out autologous vein grafts fail to restore erectile function in a rat model of cavernous nerve crush injury after nerve-sparing prostatectomy.

    PubMed

    Bessede, T; Moszkowicz, D; Alsaid, B; Zaitouna, M; Diallo, D; Peschaud, F; Benoit, G; Droupy, S

    2015-01-01

    Some autologous tissues can restore erectile function (EF) in rats after a resection of the cavernous nerve (CN). However, a cavernous nerve crush injury (CNCI) better reproduces ED occurring after a nerve-sparing radical prostatectomy (RP). The aim was to evaluate the effect on EF of an autologous vein graft after CNCI, compared with an artificial conduit. Five groups of rats were studied: those with CN exposure, exposure+vein, crush, crush+guide and crush+vein. Four weeks after surgery, the EF of rats was assessed by electrical stimulation of the CNs. The intracavernous pressure (ICP) and mean arterial pressure (MAP) were monitored during stimulations at various frequencies. The main outcome, that is, the rigidity of the erections, was defined as the ICP/MAP ratio. At 10 Hz, the ICP/MAP ratios were 41.8%, 34.7%, 20.9%, 33.9% and 20.5%, respectively. The EF was significantly lower in rats if the CNCI was treated with a vein graft instead of an artificial guide. Contrary to cases of CN resection, autologous vein grafts did not improve EF after CNCI. In terms of clinical use, the study suggests to limit an eventual use of autologous vein grafts to non-nerve-sparing RPs.

  9. Recent advances in acellular regenerative tissue scaffolds.

    PubMed

    Protzman, Nicole M; Brigido, Stephen A

    2015-01-01

    The management of chronic wounds is a considerable challenge for foot and ankle surgeons. The well-established tenets of adequate vascular supply, debridement with eradication of infection, and offloading must be employed in the management of all extremity wounds. Regenerative scaffolds are a viable means of reestablishing a favorable wound environment. The matrix facilitates cell migration, chemoattraction, angiogenesis, wound bed granulation, and expedited wound closure. Although studies have demonstrated success with acellular matrices, a multimodal approach should always be employed to improve healing success. Negative pressure wound therapy, compression, offloading, and antibiotics are advocated to improve outcomes. Acellular graft selection requires a multifactorial analysis, taking into consideration the specific patient and wound characteristics as well as the differences between acellular matrices. Patient age, comorbidities, activity level, and ability to comply with protocol as well as wound etiology, duration, depth, surface area, exudate, bacterial burden, location, vascular status, ischemic status, and presentation are all critical components. To effectively choose a matrix, the clinician must have a comprehensive understanding of the products available and the data validating their use. The mechanisms by which the acellular matrix accelerates wound healing and increases the likelihood of wound healing continue to be investigated. However, it is clear that these acellular biologic tissue scaffolds are incorporating into the host tissue, with resultant revascularization and cellular repopulation. Moving forward, additional investigations examining the effectiveness of acellular biologic tissue scaffolds to improve healing in complex, nondiabetic wounds are warranted.

  10. Nerve endoneurial microstructure facilitates uniform distribution of regenerative fibers: a post hoc comparison of midgraft nerve fiber densities.

    PubMed

    Johnson, Philip J; Newton, Piyaraj; Hunter, Daniel A; Mackinnon, Susan E

    2011-02-01

    Despite their inferiority to nerve autograft, clinical alternatives are commonly used for reconstruction of peripheral nerve injuries because of their convenient off-the-shelf availability. Previously, our group compared isografts with NeuraGen(®) (Integra, Plainsboro, NJ) nerve guides, which are a commercially available type I collagen conduit and processed rat allografts comparable to Avance(®) (AxoGen, Alachua, FL) human decellularized allograft product. From this study, qualitative observations were made of distinct differences in the pattern of regenerating fibers within conduits, acellular allografts, and isografts. In the current post hoc analysis, these observations were quantified. Using nerve density, we statistically compared the differential pattern of regenerating axon fibers within grafts and conduit. The conduits exhibited a consistent decrease in midgraft density when compared with the isograft and acellularized allografts at two gap lengths (14 mm and 28 mm) and time points (12 and 22 weeks). The decrease in density was accompanied by clustered distribution of nerve fibers in conduits, which contrasted the evenly distributed regeneration seen in processed allografts and isografts. We hypothesize that the lack of endoneurial microstructure of conduits results in the clustering regenerating fibers, and that the presence of microstructure in the acellularized allograft and isografts facilitates even distribution of regenerating fibers.

  11. 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

  12. 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

  13. 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

  14. Comparison of hemihypoglossal-facial nerve transposition with a cross-facial nerve graft and muscle transplant for the rehabilitation of facial paralysis using the facial clima method.

    PubMed

    Hontanilla, Bernardo; Vila, Antonio

    2012-02-01

    To compare quantitatively the results obtained after hemihypoglossal nerve transposition and microvascular gracilis transfer associated with a cross facial nerve graft (CFNG) for reanimation of a paralysed face, 66 patients underwent hemihypoglossal transposition (n = 25) or microvascular gracilis transfer and CFNG (n = 41). The commissural displacement (CD) and commissural contraction velocity (CCV) in the two groups were compared using the system known as Facial clima. There was no inter-group variability between the groups (p > 0.10) in either variable. However, intra-group variability was detected between the affected and healthy side in the transposition group (p = 0.036 and p = 0.017, respectively). The transfer group had greater symmetry in displacement of the commissure (CD) and commissural contraction velocity (CCV) than the transposition group and patients were more satisfied. However, the transposition group had correct symmetry at rest but more asymmetry of CCV and CD when smiling.

  15. Conduction Properties Of Decellularized Nerve Biomaterials.

    PubMed

    Urbanchek, M G; Shim, B S; Baghmanli, Z; Wei, B; Schroeder, K; Langhals, N B; Miriani, R M; Egeland, B M; Kipke, D R; Martin, D C; Cederna, P S

    2010-04-30

    The purpose of this study is to optimize poly(3,4,-ethylenedioxythiophene) (PEDOT) polymerization into decellular nerve scaffolding for interfacing to peripheral nerves. Our ultimate aim is to permanently implant highly conductive peripheral nerve interfaces between amputee, stump, nerve fascicles and prosthetic electronics. Decellular nerve (DN) scaffolds are an FDA approved biomaterial (Axogen ) with the flexible tensile properties needed for successful permanent coaptation to peripheral nerves. Biocompatible, electroconductive, PEDOT facilitates electrical conduction through PEDOT coated acellular muscle. New electrochemical methods were used to polymerize various PEDOT concentrations into DN scaffolds without the need for a final dehydration step. DN scaffolds were then tested for electrical impedance and charge density. PEDOT coated DN scaffold materials were also implanted as 15-20mm peripheral nerve grafts. Measurement of in-situ nerve conduction immediately followed grafting. DN showed significant improvements in impedance for dehydrated and hydrated, DN, polymerized with moderate and low PEDOT concentrations when they were compared with DN alone (a ≤ 0.05). These measurements were equivalent to those for DN with maximal PEDOT concentrations. In-situ, nerve conduction measurements demonstrated that DN alone is a poor electro-conductor while the addition of PEDOT allows DN scaffold grafts to compare favorably with the "gold standard", autograft (Table 1). Surgical handling characteristics for conductive hydrated PEDOT DN scaffolds were rated 3 (pliable) while the dehydrated models were rated 1 (very stiff) when compared with autograft ratings of 4 (normal). Low concentrations of PEDOT on DN scaffolds provided significant increases in electro active properties which were comparable to the densest PEDOT coatings. DN pliability was closely maintained by continued hydration during PEDOT electrochemical polymerization without compromising electroconductivity.

  16. Conduction Properties Of Decellularized Nerve Biomaterials

    PubMed Central

    Urbanchek, M.G.; Shim, B.S.; Baghmanli, Z.; Wei, B.; Schroeder, K.; Langhals, N.B.; Miriani, R.M.; Egeland, B.M.; Kipke, D.R.; Martin, D.C.; Cederna, P.S.

    2011-01-01

    The purpose of this study is to optimize poly(3,4,-ethylenedioxythiophene) (PEDOT) polymerization into decellular nerve scaffolding for interfacing to peripheral nerves. Our ultimate aim is to permanently implant highly conductive peripheral nerve interfaces between amputee, stump, nerve fascicles and prosthetic electronics. Decellular nerve (DN) scaffolds are an FDA approved biomaterial (Axogen ) with the flexible tensile properties needed for successful permanent coaptation to peripheral nerves. Biocompatible, electroconductive, PEDOT facilitates electrical conduction through PEDOT coated acellular muscle. New electrochemical methods were used to polymerize various PEDOT concentrations into DN scaffolds without the need for a final dehydration step. DN scaffolds were then tested for electrical impedance and charge density. PEDOT coated DN scaffold materials were also implanted as 15–20mm peripheral nerve grafts. Measurement of in-situ nerve conduction immediately followed grafting. DN showed significant improvements in impedance for dehydrated and hydrated, DN, polymerized with moderate and low PEDOT concentrations when they were compared with DN alone (a ≤ 0.05). These measurements were equivalent to those for DN with maximal PEDOT concentrations. In-situ, nerve conduction measurements demonstrated that DN alone is a poor electro-conductor while the addition of PEDOT allows DN scaffold grafts to compare favorably with the “gold standard”, autograft (Table 1). Surgical handling characteristics for conductive hydrated PEDOT DN scaffolds were rated 3 (pliable) while the dehydrated models were rated 1 (very stiff) when compared with autograft ratings of 4 (normal). Low concentrations of PEDOT on DN scaffolds provided significant increases in electro active properties which were comparable to the densest PEDOT coatings. DN pliability was closely maintained by continued hydration during PEDOT electrochemical polymerization without compromising

  17. 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

  18. 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.

  19. Treatment of a patient with small fiber pathology using nerve biopsy and grafting: a case report.

    PubMed

    Peled, Ziv M

    2013-10-01

    Small fiber pathology is a common clinical entity with a variable clinical presentation and etiology. Unfortunately, little has been described regarding its treatment because a majority of cases are idiopathic. Hence, treatment often consists of symptomatic management of pain and autonomic dysfunction. This report describes a patient who was presented with an undiagnosed pain syndrome thought to be affecting nerves within both lower extremities and causing significant pain. A sural nerve biopsy was performed for diagnostic purposes and nerve repair was performed using Avance nerve allograft (AxoGen Inc., Alachua, FL). Light microscopic evaluation was unremarkable, but electron microscopy revealed small fiber pathology. Postoperatively, the patient experienced a complete resolution of her pain on the involved extremity. These results suggest a potential, novel approach for treatment of such cases and possible mechanisms for the patient's clinical improvement are explored.

  20. A Human Hair Keratin Hydrogel Scaffold Enhances Median Nerve Regeneration in Nonhuman Primates: An Electrophysiological and Histological Study

    PubMed Central

    Pace, Lauren A.; Plate, Johannes F.; Mannava, Sandeep; Barnwell, Jonathan C.; Koman, L. Andrew; Li, Zhongyu; Smith, Thomas L.

    2014-01-01

    A human hair keratin biomaterial hydrogel scaffold was evaluated as a nerve conduit luminal filler following median nerve transection injury in 10 Macaca fascicularis nonhuman primates (NHP). A 1 cm nerve gap was grafted with a NeuraGen® collagen conduit filled with either saline or keratin hydrogel and nerve regeneration was evaluated by electrophysiology for a period of 12 months. The keratin hydrogel-grafted nerves showed significant improvement in return of compound motor action potential (CMAP) latency and recovery of baseline nerve conduction velocity (NCV) compared with the saline-treated nerves. Histological evaluation was performed on retrieved median nerves and abductor pollicis brevis (APB) muscles at 12 months. Nerve histomorphometry showed a significantly larger nerve area in the keratin group compared with the saline group and the keratin APB muscles had a significantly higher myofiber density than the saline group. This is the first published study to show that an acellular biomaterial hydrogel conduit filler can be used to enhance peripheral nerve regeneration and motor recovery in an NHP model. PMID:24083825

  1. 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.

  2. Nerve Allografts Supplemented with Schwann Cells Overexpressing GDNF

    PubMed Central

    Santosa, Katherine B.; Jesuraj, Nithya J.; Viader, Andreu; MacEwan, Matthew; Newton, Piyaraj; Hunter, Daniel A.; Mackinnon, Susan E.; Johnson, Philip J.

    2012-01-01

    Introduction We sought to determine if supplementation of acellular nerve allografts (ANAs) with Schwann Cells overexpressing GDNF (G-SCs) would enhance functional recovery following peripheral nerve injury. Methods SCs expanded in vitro were infected with a lentiviral vector to induce GDNF overexpression. Wild type-SCs (WT-SCs) and G-SCs were seeded into ANAs used to repair a 14mm nerve gap defect. Animals were harvested after 6 and 12 weeks for histomorphometric and muscle force analysis. Results At 6 weeks, histomorphometry revealed that ANAs supplemented with G-SCs promoted similar regeneration compared to the isograft at midgraft. However, G-SCs failed to promote regeneration into the distal stump. At 12 weeks, ANAs with G-SCs had lower maximum and specific force production compared to controls. Discussion The combined results suggest that consistent overexpression of GDNF by G-SCs trapped axons in the graft and prevented functional regeneration. PMID:23169341

  3. 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.

  4. 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

  5. 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

  6. Chitosan/silk fibroin-based, Schwann cell-derived extracellular matrix-modified scaffolds for bridging rat sciatic nerve gaps.

    PubMed

    Gu, Yun; Zhu, Jianbin; Xue, Chengbin; Li, Zhenmeiyu; Ding, Fei; Yang, Yumin; Gu, Xiaosong

    2014-02-01

    Extracellular matrix (ECM) plays a prominent role in establishing and maintaining an ideal microenvironment for tissue regeneration, and ECM scaffolds are used as a feasible alternative to cellular and molecular therapy in the fields of tissue engineering. Because of their advantages over tissue-derived ECM scaffolds, cultured cell-derived ECM scaffolds are beginning to attract attention, but they have been scarcely studied for peripheral nerve repair. Here we aimed to develop a tissue engineered nerve scaffold by reconstituting nerve cell-derived ECM with natural biomaterials. A protocol was adopted to prepare and characterize the cultured Schwann cell (SC)-derived ECM. A chitosan conduit and silk fibroin (SF) fibers were prepared, cultured with SCs for ECM deposition, and subjected to decellularization, followed by assembly into a chitosan/SF-based, SC-derived ECM-modified scaffold, which was used to bridge a 10 mm rat sciatic nerve gap. The results from morphological analysis as well as electrophysiological examination indicated that regenerative outcomes achieved by our developed scaffold were similar to those by an acellular nerve graft (namely a nerve tissue-derived ECM scaffold), but superior to those by a plain chitosan/SF scaffold. Moreover, blood and histopathological parameters confirmed the safety of scaffold modification by SC-derived ECM. Therefore, a hybrid scaffold based on joint use of acellular and classical biomaterials represents a promising approach to nerve tissue engineering.

  7. Adult-brain-derived neural stem cells grafting into a vein bridge increases postlesional recovery and regeneration in a peripheral nerve of adult pig.

    PubMed

    Liard, Olivier; Segura, Stéphanie; Sagui, Emmanuel; Nau, André; Pascual, Aurélie; Cambon, Melissa; Darlix, Jean-Luc; Fusai, Thierry; Moyse, Emmanuel

    2012-01-01

    We attempted transplantation of adult neural stem cells (ANSCs) inside an autologous venous graft following surgical transsection of nervis cruralis with 30 mm long gap in adult pig. The transplanted cell suspension was a primary culture of neurospheres from adult pig subventricular zone (SVZ) which had been labeled in vitro with BrdU or lentivirally transferred fluorescent protein. Lesion-induced loss of leg extension on the thigh became definitive in controls but was reversed by 45-90 days after neurosphere-filled vein grafting. Electromyography showed stimulodetection recovery in neurosphere-transplanted pigs but not in controls. Postmortem immunohistochemistry revealed neurosphere-derived cells that survived inside the venous graft from 10 to 240 post-lesion days and all displayed a neuronal phenotype. Newly formed neurons were distributed inside the venous graft along the severed nerve longitudinal axis. Moreover, ANSC transplantation increased CNPase expression, indicating activation of intrinsic Schwann cells. Thus ANSC transplantation inside an autologous venous graft provides an efficient repair strategy. PMID:22448170

  8. Adult-Brain-Derived Neural Stem Cells Grafting into a Vein Bridge Increases Postlesional Recovery and Regeneration in a Peripheral Nerve of Adult Pig

    PubMed Central

    Liard, Olivier; Segura, Stéphanie; Sagui, Emmanuel; Nau, André; Pascual, Aurélie; Cambon, Melissa; Darlix, Jean-Luc; Fusai, Thierry; Moyse, Emmanuel

    2012-01-01

    We attempted transplantation of adult neural stem cells (ANSCs) inside an autologous venous graft following surgical transsection of nervis cruralis with 30 mm long gap in adult pig. The transplanted cell suspension was a primary culture of neurospheres from adult pig subventricular zone (SVZ) which had been labeled in vitro with BrdU or lentivirally transferred fluorescent protein. Lesion-induced loss of leg extension on the thigh became definitive in controls but was reversed by 45–90 days after neurosphere-filled vein grafting. Electromyography showed stimulodetection recovery in neurosphere-transplanted pigs but not in controls. Postmortem immunohistochemistry revealed neurosphere-derived cells that survived inside the venous graft from 10 to 240 post-lesion days and all displayed a neuronal phenotype. Newly formed neurons were distributed inside the venous graft along the severed nerve longitudinal axis. Moreover, ANSC transplantation increased CNPase expression, indicating activation of intrinsic Schwann cells. Thus ANSC transplantation inside an autologous venous graft provides an efficient repair strategy. PMID:22448170

  9. Utilizing biologic assimilation of bovine fetal collagen in staged skin grafting.

    PubMed

    Neill, James; James, Kenneth; Lineaweaver, William

    2012-05-01

    Seven patients underwent 2-stage skin grafting with bovine fetal collagen (BFC) as an initial wound cover. Split-thickness skin grafts were successfully placed on the wounds after completion of interval management. BFC proved to be a resilient acellular dermal matrix that could proceed to assimilation and skin grafting under a variety of wound conditions. BFC may prove to be a valuable material, as the role of acellular dermal matrices in skin grafting becomes better defined.

  10. Tissue-engineered nerve constructs under a microgravity system for peripheral nerve regeneration.

    PubMed

    Luo, Hailang; Zhu, Bin; Zhang, Yongjie; Jin, Yan

    2015-01-01

    Mesenchymal stem cells (MSCs) seeded in a 3D scaffold often present characteristics of low proliferation and migration, which affect the microstructure of tissue-engineered nerves (TENs) and impair the therapeutic effects of nerve defects. By promoting MSC differentiation and mass/nutrient transport, rotary cell culture systems (RCCSs) display potential for advancing the construction of MSC-based TENs. Thus, in this study, we attempted to construct a TEN composed of adipose-derived mesenchymal stem cells (ADSCs) and acellular nerve graft (ANG) utilizing an RCCS. Compared to TENs prepared in a static 3D approach, MTT and cell count results displayed an increased number of ADSCs for TENs in an RCCS. The similarity in cell cycle states and high rates of apoptosis in the static 3D culture demonstrated that the higher proliferation in the RCCS was not due to microgravity regulation but a result of preferential mass/nutrient transport. Quantitative PCR and ELISA indicated that the RCCS promoted the expression of ADSC neural differentiation-associated genes compared to the static 3D culture. Furthermore, this difference was eliminated by adding the Notch1 signaling pathway inhibitor DAPT to the 3D static culture. TEM, axon immunostaining, and retrograde labeling analysis after sciatic nerve transplantation indicated that the TENs prepared in the RCCS exhibited more regenerative characteristics for repairing peripheral nerves than those prepared in a static 3D approach. Therefore, these findings suggest that the RCCS can modulate the construction, morphology, and function of engineered nerves as a promising alternative for nerve regeneration. PMID:25088840

  11. Cross-face nerve grafting for reanimation of incomplete facial paralysis: quantitative outcomes using the FACIAL CLIMA system and patient satisfaction.

    PubMed

    Hontanilla, Bernardo; Marre, Diego; Cabello, Alvaro

    2014-01-01

    Although in most cases Bell palsy resolves spontaneously, approximately one-third of patients will present sequela including facial synkinesis and paresis. Currently, the techniques available for reanimation of these patients include hypoglossal nerve transposition, free muscle transfer, and cross-face nerve grafting (CFNG). Between December 2008 and March 2012, eight patients with incomplete unilateral facial paralysis were reanimated with two-stage CFNG. Gender, age at surgery, etiology of paralysis denervation time, donor and recipient nerves, presence of facial synkinesis, and follow-up were registered. Commissural excursion and velocity and patient satisfaction were evaluated with the FACIAL CLIMA and a questionnaire, respectively. Mean age at surgery was 33.8 ± 11.5 years; mean time of denervation was 96.6 ± 109.8 months. No complications requiring surgery were registered. Follow-up period ranged from 7 to 33 months with a mean of 19 ± 9.7 months. FACIAL CLIMA showed improvement of both commissural excursion and velocity greater than 75% in 4 patients, greater than 50% in 2 patients, and less than 50% in the remaining two patients. Qualitative evaluation revealed a high grade of satisfaction in six patients (75%). Two-stage CFNG is a reliable technique for reanimation of incomplete facial paralysis with a high grade of patient satisfaction.

  12. Acellular pertussis vaccines in China.

    PubMed

    Wang, Lichan; Lei, Dianliang; Zhang, Shumin

    2012-11-26

    In China, whole-cell pertussis (Pw) vaccines were produced in the early 1960s and acellular pertussis (Pa) vaccines were introduced in 1995. Pa vaccines have now almost completely replaced Pw vaccines in the national immunization program. To strengthen the regulation of vaccines used in China, a vaccine lot release system was established in 2001 and Pa vaccines have been included in the system since 2006. This paper mainly described the current status of production and the quality control measures in place for Pa vaccines; and analyses quality control test data accumulated between 2006 and 2010.

  13. Wire mesh as a post-operative physiotherapy assistive device following peripheral nerve graft repair in the rat.

    PubMed

    Strasberg, S R; Watanabe, O; Mackinnon, S E; Tarasidis, G; Hertl, M C; Wells, M R

    1996-01-01

    Traditional methods of assessing nerve recovery following injury, including histomorphometry and electrophysiology, do not necessarily correlate with return of motor and sensory function. Accordingly, many investigators have used walking track analysis as an assessment of global functional recovery following sciatic, peroneal or tibial nerve injury. However, walking track reliability may be compromised by the development of flexion contractures secondary to neurologic loss. To prevent this, regular manual physiotherapy is recommended which is a time-consuming and often frustrating process for both the animal and investigator. We report the use of a wire mesh as a simple post-operative assistive device to provide constant physiotherapy. Twelve Lewis rats were randomized to one of two experimental groups. Each rat received a 2 cm posterior tibial nerve autograft. Postoperatively, animals in group 1 received manual physiotherapy, consisting of repeated flexion and extension exercises of the ankle, knee and hip every two weeks. Group 2 rats were permitted to climb freely on a 30 x 18 cm piece of wire mesh placed at a 45 degree angle within their cage. Group 2 rats received no manual physiotherapy throughout the course of the study. Serial walking tracks were performed every four weeks until sacrifice at sixteen weeks. There was no development of flexion contractures in the injured hind limbs of either group. There was no morbidity such as blisters associated with the use of the wire mesh. There was no statistical difference in walking track recovery between groups at any time period. However, a trend towards better functional recovery was seen in the group receiving constant physiotherapy via the wire mesh. The use of a wire mesh as a post-operative assistive device is an inexpensive, simple and reliable method to provide continuous physiotherapy to animals following denervation.

  14. 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

  15. 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

  16. Management of complex abdominal wall defects using acellular porcine dermal collagen.

    PubMed

    Chavarriaga, Luis Felipe; Lin, Edward; Losken, Albert; Cook, Michael W; Jeansonne, Louis O; White, Brent C; Sweeney, John F; Galloway, John R; Davis, S Scott

    2010-01-01

    Multiple techniques have been used for the repair of complex abdominal wall defects after recurrent incisional hernias with varying rates of success. Primary repair has been associated with high recurrence rates, and prosthetic mesh placement is contraindicated in contaminated surgical fields. The development of biologic prostheses has changed the approach to these difficult problems. This study evaluates the management of complex abdominal wall defects using acellular porcine dermal collagen. Between August 2006 and May 2007, 18 patients underwent abdominal wall reconstruction for complex defects with acellular porcine dermal collagen (CollaMend; Bard Inc., Warwick, RI). Patient demographics, preoperative risk factors, previous herniorrhaphy attempts, postoperative complications, recurrences, and long-term results were retrospectively reviewed. Records were reviewed at a mean follow up of 7.3 months; the recurrence rate was 44.4 per cent. A total of 38.9 per cent (seven of 18) developed a postoperative wound complications, including infection in 22.2 per cent (four of 18). All of the patients with infection required prosthesis removal as a result of encapsulation rather than incorporation of the biologic prosthesis. Acellular porcine dermal collagen has the potential for reconstruction of abdominal wall defects with postoperative wound occurrences comparable with other biologic materials. Encapsulation of the material was a major problem in cases with wound infection that required graft removal rather than local wound measures. Hernia recurrence and dehiscence of the graft were problems in noncompromised surgical fields.

  17. 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

  18. Reconstruction of a Recurrent First Dorsal Web Space Defect using Acellular Dermis

    PubMed Central

    Buck, Donald W.; Kloeters, Oliver; Eo, SuRak; Jones, Neil F.

    2007-01-01

    Oncologic defects of the hand can be problematic for the reconstructive surgeon. These defects may require a delay in definitive coverage until clear margins of resection can be obtained, which can result in a prolonged period of painful dressing changes and increased risk of soft-tissue infection. In addition, reconstructive options for oncologic defects are often limited to skin grafting, which can yield functional deficits secondary to contracted healing. Currently, there is no definitive method for preventing skin graft contracture; however, acellular dermis has been proposed as a biomechanical scaffold to enhance subsequent skin graft healing and slow this functionally debilitating process. Here, we present a patient with recurrent melanoma of the first dorsal web space. After re-resection of the melanoma, the 11 cm × 5 cm defect was reconstructed using acellular dermis as temporary coverage to allow ample time for permanent section results. Ten days later, after confirming negative margins of resection, a split-thickness skin graft (STSG) was applied over the vascularized neo-dermis. Follow-up clinical examination and the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaires were used to assess outcome. At 7 months, the patient had no recurrence of melanoma and a DASH functional reduction of only 6.9%. After approximately 18 months, the patient’s wounds had healed with excellent cosmetic and functional results, without any evidence of a web space contracture. These observations suggest that acellular dermis is a useful adjunct for wound coverage of the hand, particularly in areas of functional importance, such as the first dorsal web space. PMID:18780060

  19. 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

  20. Facial Nerve Neuroma Management

    PubMed Central

    Weber, Peter C.; Osguthorpe, J. David

    1998-01-01

    Three facial nerve neuromas were identified in the academic year 1994-1995. Each case illustrates different management dilemmas. One patient with a grade III facial nerve palsy had a small geniculate ganglion neuroma with the dilemma of decompression versus resection clear nerve section margins. The second patient underwent facial neuroma resection with cable graft reconstruction, but the permanent sections were positive. The last patient had a massive neuroma in which grafting versus other facial reconstructive options were considered. These three cases illustrate some of the major controversies in facial nerve neuroma management. We discuss our decision-making plan and report our results. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5 PMID:17171043

  1. 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

  2. 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

  3. Cadaveric nerve allotransplantation in the treatment of persistent thoracic neuralgia.

    PubMed

    Barbour, John R; Yee, Andrew; Moore, Amy M; Trulock, Elbert P; Buchowski, Jacob M; Mackinnon, Susan E

    2015-04-01

    When relief from neuralgia cannot be achieved with traditional methods, neurectomy may be considered to abate the stimulus, and primary opposition of the terminal nerve ending is recommended to prevent neuroma. Nerve repair with autograft is limited by autologous nerves available for large nerve defects. Cadaveric allografts provide an unlimited graft source without donor-site morbidities, but are rapidly rejected unless appropriate immunosuppression is achieved. An optimal treatment method for nerve allograft transplantation would minimize rejection while simultaneously permitting nerve regeneration. This report details a novel experience of nerve allograft transplantation using cadaveric nerve grafts to desensitize persistent postoperative thoracic neuralgia.

  4. 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.

  5. 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

  6. 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.

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

    PubMed

    Xu, Yunqiang; Zhang, Zhenhui; Chen, Xuyi; 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

  8. 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

  9. Acellular dermal matrix in abdominal wall reconstruction.

    PubMed

    Silverman, Ronald P

    2011-09-01

    Abdominal wall reconstruction is a complex and challenging surgical undertaking. While permanent prosthetic mesh is considered the gold standard for minimizing hernia recurrence, placement of synthetic mesh is sometimes imprudent due to contamination or risk of infection. Acellular dermal matrices (ADM) offer an exciting biologic alternative. This article provides a historical perspective on the evolution of complex ventral hernia repair leading up to and including the placement of ADM, an explanation of the biology of ADM as it relates to ventral hernia repair, and a description of the current indications, techniques, benefits, and shortcomings of its use in the abdominal wall.

  10. Bone Grafts

    MedlinePlus

    A bone graft transplants bone tissue. Surgeons use bone grafts to repair and rebuild diseased bones in your hips, knees, ... fractures or cancers. Once your body accepts the bone graft, it provides a framework for growth of new, ...

  11. 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

  12. 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

  13. 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.

  14. 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

  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. Exercise dependent increase in axon regeneration into peripheral nerve grafts by propriospinal but not sensory neurons after spinal cord injury is associated with modulation of regeneration-associated genes.

    PubMed

    Sachdeva, Rahul; Theisen, Catherine C; Ninan, Vinu; Twiss, Jeffery L; Houlé, John D

    2016-02-01

    Insufficient regeneration of central nervous system (CNS) axons contributes to persisting neurological dysfunction after spinal cord injury (SCI). Peripheral nerve grafts (PNGs) support regeneration by thousands of injured intraspinal axons and help them bypass some of the extracellular barriers that form after SCI. However this number represents but a small portion of the total number of axons that are injured. Here we tested if rhythmic sensory stimulation during cycling exercise would boost the intrinsic regenerative state of neurons to enhance axon regeneration into PNGs after a lower thoracic (T12) spinal transection of adult rats. Using True Blue retrograde tracing, we show that 4 weeks of cycling improves regeneration into a PNG from lumbar interneurons but not by primary sensory neurons. The majority of neurons that regenerate their axon are within 5 mm of the lesion and their number increased 70% with exercise. Importantly propriospinal neurons in more distant regions (5-20 mm from the lesion) that routinely exhibit very limited regeneration responded to exercise by increasing the number of regenerating neurons by 900%. There was no exercise-associated increase in regeneration from sensory neurons. Analyses using fluorescent in situ hybridization showed that this increase in regenerative response is associated with changes in levels of mRNAs encoding the regeneration associated genes (RAGs) GAP43, β-actin and Neuritin. While propriospinal neurons showed increased mRNA levels in response to SCI alone and then to grafting and exercise, sensory neurons did not respond to SCI, but there was a response to the presence of a PNG. Thus, exercise is a non-invasive approach to modulate gene expression in injured neurons leading to an increase in regeneration. This sets the stage for future studies to test whether exercise will promote axon outgrowth beyond the PNG and reconnection with spinal cord neurons, thereby demonstrating a potential clinical application of

  17. Exercise dependent increase in axon regeneration into peripheral nerve grafts by propriospinal but not sensory neurons after spinal cord injury is associated with modulation of regeneration-associated genes.

    PubMed

    Sachdeva, Rahul; Theisen, Catherine C; Ninan, Vinu; Twiss, Jeffery L; Houlé, John D

    2016-02-01

    Insufficient regeneration of central nervous system (CNS) axons contributes to persisting neurological dysfunction after spinal cord injury (SCI). Peripheral nerve grafts (PNGs) support regeneration by thousands of injured intraspinal axons and help them bypass some of the extracellular barriers that form after SCI. However this number represents but a small portion of the total number of axons that are injured. Here we tested if rhythmic sensory stimulation during cycling exercise would boost the intrinsic regenerative state of neurons to enhance axon regeneration into PNGs after a lower thoracic (T12) spinal transection of adult rats. Using True Blue retrograde tracing, we show that 4 weeks of cycling improves regeneration into a PNG from lumbar interneurons but not by primary sensory neurons. The majority of neurons that regenerate their axon are within 5 mm of the lesion and their number increased 70% with exercise. Importantly propriospinal neurons in more distant regions (5-20 mm from the lesion) that routinely exhibit very limited regeneration responded to exercise by increasing the number of regenerating neurons by 900%. There was no exercise-associated increase in regeneration from sensory neurons. Analyses using fluorescent in situ hybridization showed that this increase in regenerative response is associated with changes in levels of mRNAs encoding the regeneration associated genes (RAGs) GAP43, β-actin and Neuritin. While propriospinal neurons showed increased mRNA levels in response to SCI alone and then to grafting and exercise, sensory neurons did not respond to SCI, but there was a response to the presence of a PNG. Thus, exercise is a non-invasive approach to modulate gene expression in injured neurons leading to an increase in regeneration. This sets the stage for future studies to test whether exercise will promote axon outgrowth beyond the PNG and reconnection with spinal cord neurons, thereby demonstrating a potential clinical application of

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

    PubMed

    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

    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

  20. Interfascicular reconstruction of the peroneal nerve after knee ligament injury.

    PubMed

    McMahon, M S; Craig, S M

    1994-06-01

    Peroneal palsy is the most common lower extremity nerve injury. Although most studies emphasize particularly poor prognosis after traction injuries to the peroneal nerve, interfascicular nerve grafting has emerged as a promising technique. We describe the case of a 20-year-old man who sustained a traction injury to the peroneal nerve (0/5 foot dorsiflexion and eversion) concomitant with tears of the anterior cruciate and lateral collateral ligaments. Interfascicular sural nerve grafting (10-14 cm in length) was performed 7 months after injury and 6 months after ligament reconstruction. The patient recovered motor strength (4+/5) in both anterior and lateral compartments by 2 years' postsurgery. The results obtained indicate that interfascicular nerve grafting is a valuable technique for reconstruction of the disrupted peroneal nerve; it provides sufficient benefit to justify the time, expense, and effort involved. An aggressive approach is thus recommended in patients with peroneal nerve disruption in the setting of multiple knee ligament injuries.

  1. 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.

  2. 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

  3. Poly(lactic-co-glycolic acid) conduit for repair of injured sciatic nerve: A mechanical analysis

    PubMed Central

    Yu, Tao; Zhao, Changfu; Li, Peng; Liu, Guangyao; Luo, Min

    2013-01-01

    Tensile stress and tensile strain directly affect the quality of nerve regeneration after bridging nerve defects by poly(lactic-co-glycolic acid) conduit transplantation and autogenous nerve grafting for sciatic nerve injury. This study collected the sciatic nerve from the gluteus maximus muscle from fresh human cadaver, and established 10-mm-long sciatic nerve injury models by removing the ischium, following which poly(lactic-co-glycolic acid) conduits or autogenous nerve grafts were transplanted. Scanning electron microscopy revealed that the axon and myelin sheath were torn, and the vessels of basilar membrane were obstructed in the poly(lactic-co-glycolic acid) conduit-repaired sciatic nerve following tensile testing. There were no significant differences in tensile tests with autogenous nerve graft-repaired sciatic nerve. Following poly(lactic-co-glycolic acid) conduit transplantation for sciatic nerve repair, tensile test results suggest that maximum tensile load, maximum stress, elastic limit load and elastic limit stress increased compared with autogenous nerve grafts, but elastic limit strain and maximum strain decreased. Moreover, the tendencies of stress-strain curves of sciatic nerves were similar after transplantation of poly(lactic-co-glycolic acid) conduits or autogenous nerve grafts. Results showed that after transplantation in vitro for sciatic nerve injury, poly(lactic-co-glycolic acid) conduits exhibited good intensity, elasticity and plasticity, indicating that poly(lactic-co-glycolic acid) conduits are suitable for sciatic nerve injury repair. PMID:25206505

  4. Poly(lactic-co-glycolic acid) conduit for repair of injured sciatic nerve: A mechanical analysis.

    PubMed

    Yu, Tao; Zhao, Changfu; Li, Peng; Liu, Guangyao; Luo, Min

    2013-07-25

    Tensile stress and tensile strain directly affect the quality of nerve regeneration after bridging nerve defects by poly(lactic-co-glycolic acid) conduit transplantation and autogenous nerve grafting for sciatic nerve injury. This study collected the sciatic nerve from the gluteus maximus muscle from fresh human cadaver, and established 10-mm-long sciatic nerve injury models by removing the ischium, following which poly(lactic-co-glycolic acid) conduits or autogenous nerve grafts were transplanted. Scanning electron microscopy revealed that the axon and myelin sheath were torn, and the vessels of basilar membrane were obstructed in the poly(lactic-co-glycolic acid) conduit-repaired sciatic nerve following tensile testing. There were no significant differences in tensile tests with autogenous nerve graft-repaired sciatic nerve. Following poly(lactic-co-glycolic acid) conduit transplantation for sciatic nerve repair, tensile test results suggest that maximum tensile load, maximum stress, elastic limit load and elastic limit stress increased compared with autogenous nerve grafts, but elastic limit strain and maximum strain decreased. Moreover, the tendencies of stress-strain curves of sciatic nerves were similar after transplantation of poly(lactic-co-glycolic acid) conduits or autogenous nerve grafts. Results showed that after transplantation in vitro for sciatic nerve injury, poly(lactic-co-glycolic acid) conduits exhibited good intensity, elasticity and plasticity, indicating that poly(lactic-co-glycolic acid) conduits are suitable for sciatic nerve injury repair.

  5. 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

  6. 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

  7. 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

  8. 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.

  9. Plant grafting.

    PubMed

    Melnyk, Charles W; Meyerowitz, Elliot M

    2015-03-01

    Since ancient times, people have cut and joined together plants of different varieties or species so they would grow as a single plant - a process known as grafting (Figures 1 and 2). References to grafting appear in the Bible, ancient Greek and ancient Chinese texts, indicating that grafting was practised in Europe, the Middle East and Asia by at least the 5(th) century BCE. It is unknown where or how grafting was first discovered, but it is likely that natural grafting, the process by which two plants touch and fuse limbs or roots in the absence of human interference (Figure 3), influenced people's thinking. Such natural grafts are generally uncommon, but are seen in certain species, including English ivy. Parasitic plants, such as mistletoe, that grow and feed on often unrelated species may have also contributed to the development of grafting as a technique, as people would have observed mistletoe growing on trees such as apples or poplars. PMID:25734263

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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 ...

  16. 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

  17. 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

  18. 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.

  19. Evaluation of lymphangiogenesis in acellular dermal matrix

    PubMed Central

    Cherubino, Mario; Pellegatta, Igor; Tamborini, Federico; Cerati, Michele; Sessa, Fausto; Valdatta, Luigi

    2014-01-01

    Introduction: Much attention has been directed towards understanding the phenomena of angiogenesis and lymphangiogenesis in wound healing. Thanks to the manifold dermal substitute available nowadays, wound treatment has improved greatly. Many studies have been published about angiogenesis and cell invasion in INTEGRA®. On the other hand, the development of the lymphatic network in acellular dermal matrix (ADM) is a more obscure matter. In this article, we aim to characterize the different phases of host cell invasion in ADM. Special attention was given to lymphangiogenic aspects. Materials and Methods: Among 57 rats selected to analyse the role of ADM in lymphangiogenesis, we created four groups. We performed an excision procedure on both thighs of these rats: On the left one we did not perform any action except repairing the borders of the wound; while on the right one we used INTEGRA® implant. The excision biopsy was performed at four different times: First group after 7 days, second after 14 days, third after 21 days and fourth after 28 days. For our microscopic evaluation, we used the classical staining technique of haematoxylin and eosin and a semi-quantitative method in order to evaluate cellularity counts. To assess angiogenesis and lymphangiogenesis development we employed PROX-1 Ab and CD31/PECAM for immunohistochemical analysis. Results: We found remarkable wound contraction in defects that healed by secondary intention while minor wound contraction was observed in defects treated with ADM. At day 7, optical microscopy revealed a more plentiful cellularity in the granulation tissue compared with the dermal regeneration matrix. The immunohistochemical process highlighted vascular and lymphatic cells in both groups. After 14 days a high grade of fibrosis was noticeable in the non-treated group. At day 21, both lymphatic and vascular endothelial cells were better developed in the group with a dermal matrix application. At day 28, lymphatic endothelial

  20. 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

  1. 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

  2. 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

  3. Designing ideal conduits for peripheral nerve repair

    PubMed Central

    de Ruiter, Godard C. W.; Malessy, Martijn J. A.; Yaszemski, Michael J.; Windebank, Anthony J.; Spinner, Robert J.

    2010-01-01

    Nerve tubes, guides, or conduits are a promising alternative for autologous nerve graft repair. The first biodegradable empty single lumen or hollow nerve tubes are currently available for clinical use and are being used mostly in the repair of small-diameter nerves with nerve defects of < 3 cm. These nerve tubes are made of different biomaterials using various fabrication techniques. As a result these tubes also differ in physical properties. In addition, several modifications to the common hollow nerve tube (for example, the addition of Schwann cells, growth factors, and internal frameworks) are being investigated that may increase the gap that can be bridged. This combination of chemical, physical, and biological factors has made the design of a nerve conduit into a complex process that demands close collaboration of bioengineers, neuroscientists, and peripheral nerve surgeons. In this article the authors discuss the different steps that are involved in the process of the design of an ideal nerve conduit for peripheral nerve repair. PMID:19435445

  4. 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

  5. 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

  6. Using genipin-crosslinked acellular porcine corneal stroma for cosmetic corneal lens implants.

    PubMed

    Liu, Zhao; Zhou, Qiang; Zhu, Jixiang; Xiao, Jianhui; Wan, Pengxia; Zhou, Chenjing; Huang, Zheqian; Qiang, Na; Zhang, Wei; Wu, Zheng; Quan, Daping; Wang, Zhichong

    2012-10-01

    Acellular porcine corneal stroma (APCS) has been proven to maintain the matrix microenvironment and is therefore an ideal biomaterial for the repair and reconstruction of corneal stroma. This study aims to develop a method to prepare cosmetic corneal lens implants for leukoma using genipin-crosslinked APCS (Gc-APCS). The Gc-APCS was prepared from APCS immersed in 1.0% genipin aqueous solution (pH 5.5) for 4 h at 37 °C, followed by lyophilization at -10 °C. The color of the Gc-APCS gradually deepened to dark-blue. The degree of crosslinking was 45.7 ± 4.6%, measured by the decrease of basic and hydroxy amino acids. The porous structure and ultrastructure of collagenous lamellae were maintained, and the porosity and BET SSA were 72.7 ± 4.6% and 23.01 ± 3.45 m(2)/g, respectively. The Gc-APCS rehydrated to the physiological water content within 5 min and was highly resistant to collagenase digestion. There were no significant differences in the areal modulus and curvature variation between Gc-APCS and nature porcine cornea. The dark-blue pigments were stable to pH, light and implantation in vivo. Gc-APCS extracts had no inhibitory effects on the proliferation of keratocytes. Corneal neovascularization, graft degradation and corneal rejection were not observed within 6 months.

  7. Nerve conduction

    MedlinePlus

    ... fascicles) that contain hundreds of individual nerve fibers (neurons). Neurons consist of dendrites, axon, and cell body. The ... tree-like structures that receive signals from other neurons and from special sensory cells that sense the ...

  8. Autologous fibrin glue in peripheral nerve regeneration in vivo.

    PubMed

    Choi, Byung-Ho; Han, Sang-Gyun; Kim, Sung-Hoon; Zhu, Shi-Jiang; Huh, Jin-Young; Jung, Jae-Hyung; Lee, Seoung-Ho; Kim, Byung-Yong

    2005-01-01

    The activity of several growth factors on peripheral nerve regeneration is reported. Autologous fibrin glue contains a large number of platelets, which release significant quantities of growth factors. In order to understand the role of autologous fibrin glue in peripheral nerve regeneration, a 15-mm rabbit peroneal nerve defect was repaired using a vein graft filled with autologous fibrin glue. Axonal regeneration was examined using histological and electrophysiological methods. The extent of axonal regeneration was superior when treated with autologous fibrin glue. Our data suggest that fibrin nets formed by fibrinogen, in combination with growth factors present in autologous fibrin glue, might effectively promote peripheral nerve regeneration in nerve defects.

  9. 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

  10. 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

  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. Clinical implications of the surgical anatomy of the sural nerve.

    PubMed

    Coert, J H; Dellon, A L

    1994-11-01

    The exact anatomy of the sural nerve remains important for many clinical situations. To better understand this anatomy, 25 embalmed and 10 fresh cadaver pairs were studied. The origin of the common sural nerve in relation to the fibular head and its medial and lateral sural components were investigated. The lateral sural nerve was absent in 4 percent of the embalmed cadavers. The lateral and medial sural nerves united in the popliteal fossa in 12 percent and in the lower third of the leg in 84 percent of the cadavers. A site was identified where the lateral sural and lateral cutaneous nerve of the calf pierced the deep fascia. This site was centered about the fibular head and may be viewed as a potential site of nerve compression. There is application of these findings to nerve grafting, neuroma prevention and treatment, and sural nerve biopsy.

  13. 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

  14. 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.

  15. 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. ...

  16. 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 ...

  17. Acellular dermal matrix and negative pressure wound therapy: a tissue-engineered alternative to free tissue transfer in the compromised host.

    PubMed

    Menn, Zachary K; Lee, Edward; Klebuc, Michael J

    2012-02-01

    Free tissue transfer has revolutionized lower extremity reconstruction; however, its use in elderly patients with multiple medical problems can be associated with elevated rate s of perioperative morbidity and mortality. This study evaluates the use of acellular dermal matrix (ADM) in conjunction with negative pressure wound therapy (NPWT) and delayed skin graft application as an alternative to free tissue transfer in this compromised population. Bilayer, ADM (Integra, Plainsboro, NJ) was used in conjunction with NPWT (Wound V.A.C, Kinetic Concepts Inc., San Antonio, TX) to achieve vascularized coverage of complex lower extremity wounds with denuded tendon and bone in elderly, medically compromised patients. Following incorporation, the matrix was covered with split-thickness skin graft. Four patients (age range, 50 to 76 years) with multiple medical comorbidities were treated with the above protocol. The average time to complete vascularization of the matrix was 29 days. Definitive closure with split-thickness skin graft was achieved in three patients and one wound healed by secondary intention. No medical or surgical complications were encountered and stable soft tissue coverage was achieved in all patients. This early experience suggests that dermal substitute and NPWT with delayed skin graft application can provide a reasonable tissue-engineered alternative to free tissue transfer in the medically compromised individual.

  18. 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

  19. 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

  20. Multilayered implantation using acellular dermal matrix into nude mice.

    PubMed

    Lee, Dong Won; Lee, Myung Chul; Roh, Hyun; Lee, Won Jai

    2014-12-01

    Soft tissue augmentation using acellular dermal matrix has gained popularity to overcome the shortcomings of autogenous and alloplastic materials. Sometimes it needs multilayered stacking to obtain enough volume. In this study, we investigated the efficacy of multilayered implantation using acellular dermal matrix (MatriDerm(®)) for soft tissue augmentation. MatriDerm was implanted subdermally on each side of the dorsum of nude mice (n = 20), stacked two layers thick in the control group and three layers thick in the experimental group. Alterations of thickness, degree of angiogenesis, and collagen and elastin fiber syntheses were observed over 40 days. Three-layered implantation with MatriDerm maintained its volume similarly as in two-layered implantation, although the thickness decreased after 30 days in both groups. At the early stage of implantation, angiogenesis and collagen and elastin fiber syntheses occurred fluently on the central portion, which is the farthest away from the surface in contact with the host tissue. Collagen and elastin fibers became more concentrated over time, and the original structure of MatriDerm could not be maintained due to being replaced with newly formed collagen and elastin fibers 40 days after implantation. Multilayered implantation with MatriDerm is considered appropriate for tissue ingrowth and can be used as a substitute for soft tissue augmentation.

  1. 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

  2. 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.

  3. 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

  4. 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

  5. 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

  6. 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.

  7. Targeted delivery of adipose-derived stem cells via acellular dermal matrix enhances wound repair in diabetic rats.

    PubMed

    Nie, Chunlei; Zhang, Guoyou; Yang, Daping; Liu, Tong; Liu, Dan; Xu, Jin; Zhang, Jiewu

    2015-03-01

    Cell-based therapeutic intervention has emerged as a new approach to accelerate wound closure. Adipose-derived stem cells (ASCs), as a fascinating cell source, have received much attention in tissue repair and regeneration. In this study we evaluated the potential of acellular dermal matrix (ADM) scaffold serving as a carrier for the delivery of ASCs and investigated its therapeutic effects on wound healing. First, ASCs were isolated and characterized for multidifferentiation potential. ASCs-ADM grafts were then prepared, and ADM scaffold was shown to support the in vitro growth and proliferation of ASCs. Next, we analysed paracrine factors in conditioned medium and found that ASCs-ADM grafts secreted various cytokines, including VEGF, HGF, TGFβ and bFGF. Moreover, ASCs-ADM conditioned medium notably stimulated the migration and proliferation of fibroblasts. In vivo, we established an excisional wound model in diabetic rats which received phosphate-buffered saline (PBS), ADM or ASCs-ADM grafts, respectively. Our results demonstrated that implantation of ASCs-ADM significantly enhanced tissue regeneration and increased epithelialization, resulting in accelerated wound closure. Immunofluorescence analysis further indicated that capillary density was evidently increased in the ASCs-ADM group compared with the control or ADM group. In addition, western blot analysis showed that ASCs-ADM significantly increased the expression of angiogenic factors, which was consistent with in vitro data. Taken together, our results suggest that targeted delivery of ASCs via ADM scaffold accelerate diabetic wound healing through a paracrine mechanism, with enhanced granulation tissue formation and increased re-epithelialization and neovascularization.

  8. New approaches to bridge nerve gaps: development of a novel drug-delivering nerve conduit.

    PubMed

    Lin, Keng-Min; Sant, Himanshu J; Gale, Bruce K; Agarwal, Jayant P

    2012-01-01

    Contemporary bridging techniques for repairing nerve gaps caused by trauma require autologous nerve grafts, which are difficult to harvest and handle and result in significant donor site deficit. Several nerve conduits with axon growth-enhancing potential have been proposed, developed and tested over the past fifteen years. In this work, prototypes of a nerve conduit designed to bridge large nerve gaps (≥10mm) end-to-end were incorporated with concentric drug reservoirs for constant and controlled drug delivery to enhance axon growth. These devices were designed, fabricated and tested in vitro in amber glass vials with bovine serum albumin in order to determine the drug release kinetics for future application. Our devices have shown the capability to deliver the drug of interest over a 6-day period.

  9. Neuroma-in-continuity of the median nerve managed by nerve expansion and direct suture with vein conduit.

    PubMed

    Jeudy, J; Raimbeau, G; Rabarin, F; Fouque, P A; Saint-Cast, Y; Césari, B; Bigorre, N

    2014-06-01

    Autologous nerve grafting is the current standard for bridging large gaps in major sensory and motor nerves. It allows both function and pain improvement with predictable results. Clinical observations of nerve elongation caused by tumours have prompted experimental animal studies of induced gradual elongation of the nerve stump proximal to the gap. This technique allows direct suturing of the two nerve ends to bridge the gap. Here, we describe a case of neuroma-in-continuity of the median nerve managed by resection and direct suture after nerve elongation with a tissue expander. We are not aware of similar reported cases. Secondary repair 3 years after the initial injury improved the pain and hypersensitivity and restored a modest degree of protective sensory function (grade S1).

  10. 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

  11. 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.

  12. 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

  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. 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

  16. 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

  17. Use of bovine pericardium graft for abdominal wall reconstruction in contaminated fields

    PubMed Central

    D’Ambra, Luigi; Berti, Stefano; Feleppa, Cosimo; Magistrelli, Prospero; Bonfante, Pierfrancesco; Falco, Emilio

    2012-01-01

    AIM: To employ, in such conditions, a biological graft such as bovine pericardium that offers resistance to infection. METHODS: In our surgical department, from January 2006 to June 2010, 48 patients underwent abdominal wall reconstruction using acellular bovine pericardium; of these 34 patients had a contaminated wound due to diffuse peritonitis (complicated diverticulitis, bowel perforation, intestinal infarction, strangled hernia, etc.) and 14 patients had hernia relapse on infected synthetic mesh. RESULTS: In our series, one patient died of multi-organ failure 3 d after surgery. After placement of the pericardium mesh four cases of hernia relapse occurred. CONCLUSION: Recurrence rate is similar to that of prosthetic mesh repair and the application of acellular bovine pericardium (Tutomesh®, Tutogen Medical Gmbh Germany) is moreover a safe and feasible option that can be employed to manage complicated abdominal wall defects where prosthetic mesh is unsuitable. PMID:22905285

  18. 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

  19. 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

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

    PubMed

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

    2014-05-02

    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.

  1. 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.

  2. 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

  3. 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

  4. Nerve Impulses in Plants

    ERIC Educational Resources Information Center

    Blatt, F. J.

    1974-01-01

    Summarizes research done on the resting and action potential of nerve impulses, electrical excitation of nerve cells, electrical properties of Nitella, and temperature effects on action potential. (GS)

  5. 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.

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

    PubMed Central

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

    2015-01-01

    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 × 106 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

  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. Investigation of the regenerative capacity of an acellular porcine medial meniscus for tissue engineering applications.

    PubMed

    Stapleton, Thomas W; 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 term.

  9. Acellular Hydrogels for Regenerative Burn Wound Healing: Translation from a Porcine Model.

    PubMed

    Shen, Yu-I; Song, Hyun-Ho G; Papa, Arianne E; Burke, Jacqueline A; Volk, Susan W; Gerecht, Sharon

    2015-10-01

    Currently available skin grafts and skin substitutes for healing following third-degree burn injuries are fraught with complications, often resulting in long-term physical and psychological sequelae. Synthetic treatment that can promote wound healing in a regenerative manner would provide an off-the-shelf, non-immunogenic strategy to improve clinical care of severe burn wounds. Here, we demonstrate the vulnerary efficacy and accelerated healing mechanism of a dextran-based hydrogel in a 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 re-epithelialization, enhanced extracellular matrix remodeling, and greater nerve reinnervation, compared with 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

  10. Acellular Hydrogels for Regenerative Burn Wound Healing: Translation from a Porcine Model.

    PubMed

    Shen, Yu-I; Song, Hyun-Ho G; Papa, Arianne E; Burke, Jacqueline A; Volk, Susan W; Gerecht, Sharon

    2015-10-01

    Currently available skin grafts and skin substitutes for healing following third-degree burn injuries are fraught with complications, often resulting in long-term physical and psychological sequelae. Synthetic treatment that can promote wound healing in a regenerative manner would provide an off-the-shelf, non-immunogenic strategy to improve clinical care of severe burn wounds. Here, we demonstrate the vulnerary efficacy and accelerated healing mechanism of a dextran-based hydrogel in a 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 re-epithelialization, enhanced extracellular matrix remodeling, and greater nerve reinnervation, compared with 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.

  11. 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.

  12. 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

  13. 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

  14. 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

  15. Characterization of co-purified acellular pertussis vaccines.

    PubMed

    Xu, Yinghua; Tan, Yajun; Asokanathan, Catpagavalli; Zhang, Shumin; Xing, Dorothy; Wang, Junzhi

    2015-01-01

    Whole-cell pertussis vaccines (WPVs) have been completely replaced by the co-purified acellular vaccines (APVs) in China. To date few laboratory studies were reported for co-purified APVs in terms of their antigenic composition and protective immune responses. To further understand the antigenic composition in co-purified APVs, in the present study 2-dimensional gel electrophoresis-based proteomic technology was used to analyze the composition of co-purified APVs. The results showed that besides the main antigens pertussis toxin (PT) and filamentous hemagglutinin (FHA), co-purified APVs also contained pertactin (PRN), fimbriae (FIM) 2and3 and other minor protein antigens. Of the 9 proteins identified, 3 were differentially presented in products from manufacturer 1 and manufacturer 2. Compared with WPVs and purified APVs, co-purified APVs induced a mixed Th1/Th2 immune response with more toward to a Th1 response than the purified APVs in this study. These results hint that different immune mechanisms might be involved in protection induced by co-purified and purified APVs.

  16. Characterization of co-purified acellular pertussis vaccines

    PubMed Central

    Xu, Yinghua; Tan, Yajun; Asokanathan, Catpagavalli; Zhang, Shumin; Xing, Dorothy; Wang, Junzhi

    2015-01-01

    Whole-cell pertussis vaccines (WPVs) have been completely replaced by the co-purified acellular vaccines (APVs) in China. To date few laboratory studies were reported for co-purified APVs in terms of their antigenic composition and protective immune responses. To further understand the antigenic composition in co-purified APVs, in the present study 2-dimensional gel electrophoresis-based proteomic technology was used to analyze the composition of co-purified APVs. The results showed that besides the main antigens pertussis toxin (PT) and filamentous hemagglutinin (FHA), co-purified APVs also contained pertactin (PRN), fimbriae (FIM) 2and3 and other minor protein antigens. Of the 9 proteins identified, 3 were differentially presented in products from manufacturer 1 and manufacturer 2. Compared with WPVs and purified APVs, co-purified APVs induced a mixed Th1/Th2 immune response with more toward to a Th1 response than the purified APVs in this study. These results hint that different immune mechanisms might be involved in protection induced by co-purified and purified APVs. PMID:25610957

  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. Secondary optic nerve tumors.

    PubMed

    Christmas, N J; Mead, M D; Richardson, E P; Albert, D M

    1991-01-01

    Secondary tumors of the optic nerve are more common than primary optic nerve tumors. The involvement of the optic nerve may arise from direct invasion from intraocular malignancies, from hematopoietic malignancy, from meningeal carcinomatosis, or from distant primary tumors. Orbital tumors rarely invade the optic nerve, and brain tumors involve it only in their late stages.

  19. Cavernous nerve reconstruction to preserve erectile function following non-nerve-sparing radical retropubic prostatectomy: a prospective study.

    PubMed

    Chang, David W; Wood, Christopher G; Kroll, Stephen S; Youssef, Adel A; Babaian, Richard J

    2003-03-01

    Erectile dysfunction following radical prostatectomy for treatment of clinically localized prostate cancer remains a problem that deters many men from seeking surgical treatment. Sparing the cavernous nerves has been popularized as a method of preserving potency, but men with locally advanced disease may be at increased risk for positive margins with this technique. In this study, sural nerve grafting of the cavernous nerve bundles, to preserve postoperative potency while potentially maximizing cancer control, was examined. Thirty men were enrolled in this prospective phase I study and underwent non-nerve-sparing radical prostatectomy performed by one of two protocol surgeons. Preoperative erectile function was assessed both objectively, using a RigiScan (Timm Medical Technologies, Inc., Eden Prairie, Minn.), and subjectively. The cavernous nerves were identified and resected during the operation with the use of an intraoperative mapping device (CaverMap; Alliant Medical Technologies, Norwood, Mass.). Bilateral autologous sural nerve grafting to the cavernous nerve stumps was performed by one of two protocol plastic surgeons. Postoperative erectile dysfunction therapy, using intracorporeal injection, a vacuum pump, and/or oral sildenafil therapy, was instituted 6 weeks after the operation. Spontaneous erectile activity was subjectively and objectively measured every 3 months after the operation. Follow-up periods ranged from 13 to 33 months (mean, 23 months). Overall, 18 of 30 patients (60 percent) demonstrated both objective and subjective evidence of spontaneous erectile activity. Of those 18 men, 13 (72 percent) were able to have intercourse (seven unassisted and six with the aid of sildenafil). No disease or biochemical recurrences have been noted in this group of patients with locally advanced disease. In conclusion, autologous sural nerve grafting after non-nerve-sparing radical prostatectomy is an effective means of preserving spontaneous erectile activity

  20. Development of a scaffoldless three-dimensional engineered nerve using a nerve-fibroblast co-culture

    PubMed Central

    Baltich, Jennifer; Hatch-Vallier, Leah; Adams, Aaron M.; Arruda, Ellen M.; Larkin, Lisa M.

    2009-01-01

    Nerve grafts are often required to replace tissue damaged by disease, surgery, or extensive trauma. Limitations such as graft availability, donor site morbidity, and immune rejection have led investigators to develop strategies to engineer nerve tissue. The goal of this study was to fabricate a scaffoldless three-dimensional (3D) nerve construct using a co-culture of fetal nerve cells with a fibroblast monolayer and allow the co-culture to remodel into a 3D construct with an external fibroblast layer and an internal core of interconnected neuronal cells. Primary fibroblasts were seeded on laminin-coated plates and allowed to form a confluent monolayer. Neural cells isolated from E-15 spinal cords were seeded on top of the fibroblast monolayer and allowed to form a networked monolayer across the monolayer of fibroblasts. Media shifts initiated contraction of the fibroblast monolayer and a remodeling of the co-culture into a 3D construct held statically in place by the two constraint pins. Immunohisto-chemistry using S100 (Schwann cell), β3-tubulin, DAPI, and collagen I indicated an inner core of nerve cells surrounded by an external layer of fibroblasts. Conduction velocities of the 3D nerve and control (fibroblast-only) constructs were measured in vitro and compared to in vivo measures of neonatal sciatic nerve. The conduction velocities of the nerve constructs were comparable to 24-d-old neonatal nerve. The presence of Schwann cells and the ability to conduct neuronal signals in vitro suggest the scaffoldless 3D nerve constructs will be a viable option for nerve repair. PMID:19997868

  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. [Vascular graft prosthesis].

    PubMed

    Chakfé, N; Dieval, F; Thaveau, F; Rinckenbach, S; Hassani, O; Camelot, G; Durand, B; Kretz, J-G

    2004-06-01

    Performed since the 1950s, vascular grafting has opened modern era of vascular surgery. Autologous venous grafts are of first choice for revascularisation of small arteries. Synthetic grafts are mainly modelled using microporous polytetrafluoroethylene or terephtalate polyethylene. These prosthesis are mainly used for revascularization of medium and large size arteries. PMID:15220107

  3. 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

  4. Pertactin deficient Bordetella pertussis present a better fitness in mice immunized with an acellular pertussis vaccine.

    PubMed

    Hegerle, N; Dore, G; Guiso, N

    2014-11-20

    Bordetella pertussis is the etiologic agent of whooping cough and has been the target of vaccination for over fifty years. The latest strategies include the use of acellular pertussis vaccines that induce specific immunity against few virulence factors amongst which pertactin is included in three and five component acellular pertussis vaccines. Recently, it has been reported that B. pertussis clinical isolates loose the production of this adhesin in regions reaching high vaccine coverage with vaccines targeting this virulence factor. We here demonstrate that isolates not producing pertactin are capable of sustaining longer infection as compared to pertactin producing isolates in an in vivo model of acellular pertussis immunization. Loosing pertactin production might thus provide a selective advantage to these isolates in this background, which could account for the upraise in prevalence of these pertactin deficient isolates in the population.

  5. Acellular comet assay: a tool for assessing variables influencing the alkaline comet assay.

    PubMed

    Kennedy, Erin K; McNamee, James P; Prud'homme Lalonde, Louise; Jones, Trevor; Wilkinson, Diana

    2012-01-01

    In this study, an acellular modification to the alkaline comet assay to further evaluate key variables within the assay that may influence the outcome of genotoxicity studies is described. This acellular comet assay can detect differences of 0.2 Gy of (60)Co gamma-ray radiation between 0 and 1 Gy and differences of 1 Gy between 0 and 8 Gy; thus, this assay is applicable for a wide range of DNA damage levels. It is also shown that DNA damage from different radiation energies was not significantly different from (60)Co gamma-ray. This assay displayed a statistical increase in DNA damage due to uncontrolled exposure to natural light; however, the slope of the dose-response curve for light-exposed samples was similar to that for samples protected from light. A comparison of the alkaline comet assay with the acellular comet assay allowed for the intrinsic repair capacity of the alkaline comet assay to be quantified.

  6. Nerve Injuries in Athletes.

    PubMed

    Collins, K; Storey, M; Peterson, K; Nutter, P

    1988-01-01

    In brief: Nerve injuries in athletes may be serious and may delay or prevent an athlete's return to his or her sport. Over a two-year period, the authors evaluated the condition of 65 patients who had entrapments of a nerve or nerve root, documented with electromyography. They describe four case histories: Two patients had radial nerve entrapments, one caused by baseball pitching and the other by kayaking; one football player had combined suprascapular neuropathy and upper trunk brachial plexopathy; and one patient had carpal tunnel syndrome of a median nerve secondary to rowing. Sports-related peripheral nerve lesions of the lower extremity were not seen during the study period. Based on a literature review, the nerve injuries discussed represent the spectrum of nerve entrapments likely to be seen in US clinics. The authors conclude that peripheral nerve lesions should be considered in the differential diagnosis of sports injuries, particularly at the shoulder, elbow, and wrist.

  7. Interstitial engraftment of adipose-derived stem cells into an acellular dermal matrix results in improved inward angiogenesis and tissue incorporation.

    PubMed

    Komatsu, Issei; Yang, Jun; Zhang, Ying; Levin, L Scott; Erdmann, Detlev; Klitzman, Bruce; Hollenbeck, Scott T

    2013-10-01

    Acellular dermal matrices (ADM) are commonly used in reconstructive procedures and rely on host cell invasion to become incorporated into host tissues. We investigated different approaches to adipose-derived stem cells (ASCs) engraftment into ADM to enhance this process. Lewis rat adipose-derived stem cells were isolated and grafted (3.0 × 10(5) cells) to porcine ADM disks (1.5 mm thick × 6 mm diameter) using either passive onlay or interstitial injection seeding techniques. Following incubation, seeding efficiency and seeded cell viability were measured in vitro. In addition, Eighteen Lewis rats underwent subcutaneous placement of ADM disk either as control or seeded with PKH67 labeled ASCs. ADM disks were seeded with ASCs using either onlay or injection techniques. On day 7 and or 14, ADM disks were harvested and analyzed for host cell infiltration. Onlay and injection techniques resulted in unique seeding patterns; however cell seeding efficiency and cell viability were similar. In-vivo studies showed significantly increased host cell infiltration towards the ASCs foci following injection seeding in comparison to control group (p < 0.05). Moreover, regional endothelial cell invasion was significantly greater in ASCs injected grafts in comparison to onlay seeding (p < 0.05). ADM can successfully be engrafted with ASCs. Interstitial engraftment of ASCs into ADM via injection enhances regional infiltration of host cells and angiogenesis, whereas onlay seeding showed relatively broad and superficial cell infiltration. These findings may be applied to improve the incorporation of avascular engineered constructs.

  8. [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

  9. Histochemical and morphological studies on a new type of acellular cartilage.

    PubMed

    Junqueira, L C; Toledo, O M; Montes, G S

    1983-01-01

    A new type of cartilage was found participating in a valve-like system inside the conus arteriosus of the fresh water sting ray, Potamotrygon sp.. This cartilage possesses no chondrocytes and its matrix is perforated by vascular channels that ramify dendritically forming canaliculi. The acellular cartilage does not possess perichondrium but, rather, it is attached to a basement membrane-like structure. The cartilaginous matrix contains collagen fibrils that strongly interact with the chondroitin sulfate of the ground substance. The histochemical and biochemical findings suggest that not all of the glycosaminoglycans present in the acellular cartilage are bound to protein cores to form proteoglycans. PMID:6407464

  10. 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.

  11. Engineered Composite Tissue as a Bioartificial Limb Graft

    PubMed Central

    Jank, Bernhard J.; Xiong, Linjie; Moser, Philipp T.; Guyette, Jacques P.; Ren, Xi; Leonard, David A.; Fernandez, Leopoldo; Ott, Harald C.

    2015-01-01

    The loss of an extremity is a disastrous injury with tremendous impact on a patient’s life. Current mechanical prostheses are technically highly sophisticated, but only partially replace physiologic function and aesthetic appearance. As a biologic alternative, approximately 70 patients have undergone allogeneic hand transplantation to date worldwide. While outcomes are favorable, risks and side effects of transplantation and long-term immunosuppression pose a significant ethical dilemma. An autologous, bio-artificial graft based on native extracellular matrix and patient derived cells could be produced on demand and would not require immunosuppression after transplantation. To create such a graft, we decellularized rat and primate forearms by detergent perfusion and yielded acellular scaffolds with preserved composite architecture. We then repopulated muscle and vasculature with cells of appropriate phenotypes, and matured the composite tissue in a perfusion bioreactor under electrical stimulation in vitro. After confirmation of composite tissue formation, we transplanted the resulting bio-composite grafts to confirm perfusion in vivo. PMID:26004237

  12. Thoracic sympathetic nerve reconstruction for compensatory hyperhidrosis: the Melbourne technique

    PubMed Central

    Hensman, Chris; Leong, James

    2014-01-01

    Background Compensatory hyperhidrosis (CH) is a potential complication following endoscopic thoracic sympathectomy (ETS) in the management of primary hyperhidrosis. CH is considered a permanent condition with significant psychosocial impacts but with few treatment options. Various reversal surgical techniques, aimed at reconstituting sympathetic pathways, have been developed but results have been inconsistent. Objective We present two case reports of a novel technique of reversal surgery, the Melbourne technique, which was employed to treat severe CH that developed within 3-5 months following ETS. Both patients were followed-up to 8 years. Methods The Melbourne technique employs an endoscopic approach to expose previously sympathectomized or sympathotomized thoracic sympathetic chains. In these two cases it was performed on the right side only. Instead of an interpositional nerve graft, an autogenous vein graft was simultaneously harvested and used as a nerve conduit to bridge the secondary nerve defect after neuroma excision. Long-term outcomes were assessed using the dermatology life quality index (DLQI) and the quality of life (QoL) questionnaires, which are validated for hyperhidrosis. Results In both cases, patients reported postoperative improvements in QoL scores. However, the improvement was more marked in one case compared with the other. There were no significant immediate and long-term postoperative complications. Conclusions The Melbourne technique shows promise as an alternative to interpositional nerve grafts or nerve transfers employed in other endoscopic reversal surgeries for CH. PMID:25333020

  13. 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

  14. 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.

  15. 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

  16. Common peroneal nerve dysfunction

    MedlinePlus

    ... toe-out movements Tests of nerve activity include: Electromyography (EMG, a test of electrical activity in muscles) Nerve ... Peroneal neuropathy. In: Preston DC, Shapiro BE, eds. Electromyography and Neuromuscular Disorders . 3rd ed. Philadelphia, PA: Elsevier; ...

  17. Nerve conduction velocity

    MedlinePlus

    ... to measure the speed of the nerve signals. Electromyography (recording from needles placed into the muscles) is ... Often, the nerve conduction test is followed by electromyography (EMG). In this test, needles are placed into ...

  18. 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.

  19. 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)

  20. 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

  1. 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

  2. Development and characterization of acellular porcine pulmonary valve scaffolds for tissue engineering.

    PubMed

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

    2014-11-01

    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

  3. 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

  4. Distal nerve entrapment following nerve repair.

    PubMed

    Schoeller, T; Otto, A; Wechselberger, G; Pommer, B; Papp, C

    1998-04-01

    Failure of nerve repair or poor functional outcome after reconstruction can be influenced by various causes. Besides improper microsurgical technique, fascicular malalignment and unphysiologic tension, we found in our clinical series that a subclinical nerve compression distal to the repair site can seriously impair regeneration. We concluded that the injured nerve, whether from trauma or microsurgical intervention, could be more susceptible to distal entrapment in the regenerative stage because of its disturbed microcirculation, swelling and the increase of regenerating axons followed by increased nerve volume. In two cases we found the regenerating nerve entrapped at pre-existing anatomical sites of narrowing resulting in impaired functional recovery. In both cases the surgical therapy was decompression of the distal entrapped nerve and this was followed by continued regeneration. Thorough clinical and electrophysiologic follow-up is necessary to detect such adverse compression effects and to distinguish between the various causes of failed regeneration. Under certain circumstances primary preventive decompression may be beneficial if performed at the time of nerve coaptation.

  5. Allograft pretreatment for the repair of sciatic nerve defects: green tea polyphenols versus radiation

    PubMed Central

    Zhou, Sheng-hu; Zhen, Ping; Li, Shen-song; Liang, Xiao-yan; Gao, Ming-xuan; Tian, Qi; Li, Xu-sheng

    2015-01-01

    Pretreatment of nerve allografts by exposure to irradiation or green tea polyphenols can eliminate neuroimmunogenicity, inhibit early immunological rejection, encourage nerve regeneration and functional recovery, improve tissue preservation, and minimize postoperative infection. In the present study, we investigate which intervention achieves better results. We produced a 1.0 cm sciatic nerve defect in rats, and divided the rats into four treatment groups: autograft, fresh nerve allograft, green tea polyphenol-pretreated (1 mg/mL, 4°C) nerve allograft, and irradiation-pretreated nerve allograft (26.39 Gy/min for 12 hours; total 19 kGy). The animals were observed, and sciatic nerve electrophysiology, histology, and transmission electron microscopy were carried out at 6 and 12 weeks after grafting. The circumference and structure of the transplanted nerve in rats that received autografts or green tea polyphenol-pretreated nerve allografts were similar to those of the host sciatic nerve. Compared with the groups that received fresh or irradiation-pretreated nerve allografts, motor nerve conduction velocity in the autograft and fresh nerve allograft groups was greater, more neurites grew into the allografts, Schwann cell proliferation was evident, and a large number of new blood vessels was observed; in addition, massive myelinated nerve fibers formed, and abundant microfilaments and microtubules were present in the axoplasm. Our findings indicate that nerve allografts pretreated by green tea polyphenols are equivalent to transplanting autologous nerves in the repair of sciatic nerve defects, and promote nerve regeneration. Pretreatment using green tea polyphenols is better than pretreatment with irradiation. PMID:25788934

  6. 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

  7. 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

  8. 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

  9. 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

  10. Human histology of allogeneic block grafts for alveolar ridge augmentation: case report.

    PubMed

    Morelli, Thiago; Neiva, Rodrigo; Wang, Hom-Lay

    2009-12-01

    Autogenous bone grafts obtained from the mandibular symphysis or ramus are the primary donor sites for harvesting bone in the oral cavity to correct ridge deficiencies. Although such bone grafts can be successful, several concerns remain, such as donor site morbidity, nerve paresthesia, devitalization of natural teeth, and postoperative complications (eg, swelling, discomfort, and pain). To avoid these concerns and overcome the limited amount of autogenous intraoral bone for grafting, allogeneic block grafts were introduced. The purposes of this paper were to introduce allogeneic block grafts, demonstrate the integration of these allogeneic block grafts into the recipient site by detailed histology, and describe the step-by-step surgical technique of how this graft was used in a patient. A literature search was conducted to identify papers related to allogeneic block grafting, and papers were reviewed and summarized. The advantages and disadvantages of allogeneic block grafting were presented based on the literature and the authors' experience. One patient treated with allogeneic block graft was illustrated. The histologic evidence obtained from this patient indicated good bone remodeling and significant amount of new bone formation. The literature and clinical experience have shown that allogeneic block grafts can be used successfully to augment deficient ridges. PMID:20072743

  11. Calcar bone graft

    SciTech Connect

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

    1986-01-01

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

  12. Delayed skin grafting.

    PubMed

    Ceilley, R I; Bumsted, R M; Panje, W R

    1983-04-01

    The use of skin grafts on granulating wounds is an established practice. Delaying the application of a full- or split-thickness skin graft may be an advantageous alternative method of surgical reconstruction in selected cases. Partial healing by secondary intention is useful for filling in deeper defects and usually produces a wound that is much smaller and of more normal contour than the original defect. Contraction of the graft bed is markedly influenced by location, tissue laxity, surface tension lines, motion, and wound geometry. Proper wound care, correct surgical preparation of the defect, and timing of the graft procedure are all important considerations in maximizing the overall result. Through-and-through defects and wounds produced over areas with little underlying support (eyelids and lip) often need flap reconstruction or immediate grafting to prevent undesirable functional and cosmetic results. By combining delayed healing and conventional reconstructive techniques, major tissue loss can often be restored while minimizing patient morbidity.

  13. Grafts in "closed" rhinoplasty.

    PubMed

    Scattolin, A; D'Ascanio, L

    2013-06-01

    Rhinoplasty is a fascinating and complex surgical procedure aiming at attaining a well-functioning and aesthetically pleasant nose. The use of grafts is of the utmost importance for the nasal surgeon to achieve such results. However, the philosophy and technical use of nasal grafts are different in "closed" and "open" rhinoplasty. The aim of this paper is not detailed description of the numerous grafts reported in the literature; we will describe the main principles of grafts use in "closed" rhinoplasty derived from our experience, with special reference to the philosophical and technical differences in their employment between "closed" and "open" rhinoplasty. Some cases are reported as an example of graft use in "endonasal" approach rhinoplasty.

  14. 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

  15. Mesenchymal stem cells seeded on cross-linked and noncross-linked acellular porcine dermal scaffolds for long-term full-thickness hernia repair in a small animal model.

    PubMed

    Mestak, Ondrej; Matouskova, Eva; Spurkova, Zuzana; Benkova, Kamila; Vesely, Pavel; Mestak, Jan; Molitor, Martin; Pombinho, Antonio; Sukop, Andrej

    2014-07-01

    Biological meshes are biomaterials consisting of extracellular matrix that are used in surgery particularly for hernia treatment, thoracic wall reconstruction, or silicone implant-based breast reconstruction. We hypothesized that combination of extracellular matrices with autologous mesenchymal stem cells used for hernia repair would result in increased vascularization and increased strength of incorporation. We cultured autologous adipose-derived stem cells harvested from the inguinal region of Wistar rats on cross-linked and noncross-linked porcine extracellular matrices. In 24 Wistar rats, a standardized 2×4 cm fascial defect was created and repaired with either cross-linked or noncross-linked grafts enriched with stem cells. Non-MSC-enriched grafts were used as controls. The rats were sacrificed at 3 months of age. The specimens were examined for the strength of incorporation, vascularization, cell invasion, foreign body reaction, and capsule formation. Both materials showed cellular ingrowth and neovascularization. Comparison of both tested groups with the controls showed no significant differences in the capsule thickness, foreign body reaction, cellularization, or vascularization. The strength of incorporation of the stem cell-enriched cross-linked extracellular matrix specimens was higher than in acellular specimens, but this result was statistically nonsignificant. In the noncross-linked extracellular matrix, the strength of incorporation was significantly higher in the stem cell group than in the acellular group. Seeding of biological meshes with stem cells does not significantly contribute to their increased vascularization. In cross-linked materials, it does not ensure increased strength of incorporation, in contrast to noncross-linked materials. Owing to the fact that isolation and seeding of stem cells is a very complex procedure, we do not see sufficient benefits for its use in the clinical setting.

  16. 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

  17. 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.

  18. 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

  19. Hybrid small-diameter vascular grafts: Anti-expansion effect of electrospun poly ε-caprolactone on heparin-coated decellularized matrices.

    PubMed

    Gong, Wenhui; Lei, Dong; Li, Sen; Huang, Peng; Qi, Quan; Sun, Yijun; Zhang, Yijie; Wang, Zhe; You, Zhengwei; Ye, Xiaofeng; Zhao, Qiang

    2016-01-01

    Small-diameter vascular grafts (SDVGs) (D < 6 mm) are increasingly needed in clinical settings for cardiovascular disease, including coronary artery and peripheral vascular pathologies. Vessels made from synthetic polymers have shortcomings such as thrombosis, intimal hyperplasia, calcification, chronic inflammation and no growth potential. Decellularized xenografts are commonly used as a tissue-engineering substitute for vascular reconstructive procedures. Although acellular allogeneic vascular grafts have good histocompatibility and antithrombotic properties, the decellularization process may damage the biomechanics and accelerate the elastin deformation and degradation, finally resulting in vascular graft expansion and even aneurysm formation. Here, to address these problems, we combine synthetic polymers with natural decellularized small-diameter vessels to fabricate hybrid tissue-engineered vascular grafts (HTEV). The donor aortic vessels were decellularized with a combination of different detergents and dehydrated under a vacuum freeze-drying process. Polycaprolactone (PCL) nanofibers were electrospun (ES) outside the acellular aortic vascular grafts to strengthen the decellularized matrix. The intimal surfaces of the hybrid small-diameter vascular grafts were coated with heparin before the allograft transplantation. Histopathology and scanning electron microscope revealed that the media of the decellularized vessels were severely injured. Mechanical testing of scaffolds showed that ES-PCL significantly enhanced the biomechanics of decellularized vessels. Vascular ultrasound and micro-CT angiography showed that all grafts after implantation in a rat model were satisfactorily patent for up to 6 weeks. ES-PCL successfully prevented the occurrence of vasodilation and aneurysm formation after transplantation and reduced the cell inflammatory infiltration. In conclusion, the HTEV with perfect histocompatibility and biomechanics provide a facile and useful

  20. 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

  1. 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

  2. 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

  3. Infrainguinal anastomotic arterial graft infections treated by selective graft preservation.

    PubMed Central

    Calligaro, K D; Westcott, C J; Buckley, R M; Savarese, R P; DeLaurentis, D A

    1992-01-01

    The purpose of this study was to determine whether the type of graft material and bacteria involved in an infrainguinal arterial anastomotic infection can be used as guidelines for graft preservation. Between 1972 and 1990, the authors treated 35 anastomotic infections involving a common femoral or distal artery. The graft material was Dacron in 14 patients, polytetrafluoroethylene (PTFE) in 14, and vein in 7. Of the 14 Dacron grafts, immediate graft excision was required for overwhelming infection in eight patients (bleeding in five, sepsis in three) and for an occluded graft in one patient. Three of five patients failed attempted graft preservation because of nonhealing wounds. Thus, 12 of the 14 Dacron grafts ultimately required graft excision. Of the 21 "smooth-walled" vein and PTFE grafts, 10 required immediate graft excision for occluded grafts (five PTFE, one vein) or bleeding (three PTFE, one vein). Ten of the remaining 11 (91%) patients with patent "smooth-walled" grafts, intact anastomoses, and absence of sepsis managed by graft preservation healed their wounds and maintained distal arterial perfusion. Wound cultures grew pure gram-positive cocci in 17 of 21 "smooth-walled" graft infections versus 8 of 14 Dacron graft infections. In the absence of systemic sepsis, graft preservation is the treatment of choice for gram-positive infections involving an intact anastomosis of patent PTFE and vein grafts. Regardless of the bacterial cause, the authors recommend that any infrainguinal anastomotic infection of a Dacron graft be treated by immediate excision of all infected graft material. PMID:1632705

  4. 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

  5. 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

  6. Crosslinked grafted PVC obtained by direct radiation grafting

    NASA Astrophysics Data System (ADS)

    Hegazy, El-Sayed A.; Dessouki, Ahmed M.; El-Dessouky, Maher M.; El-Sawy, Naeem M.

    Direct radition-induced grafting of 4-vinylpyridine onto both pure and plasticized poly(vinyl chloride) has been studied. The effect of grafting conditions such as solvent, monomer concentration, irradiation dose, and inhibitor concentration on the grafting yield was investigated. The grafting process was enhanced by using distilled water as diluent and higher degrees of grafting were obtained as compared with other solvents used (benzene, methanol, and a mixture of methanol and water). The homopolymerization of 4-vinylpyridine was reduced to a minimum using ammonium ferrous sulfate and the suitable optimum concentration of the inhibitor was found to be 0.25 wt %. It was observed that the degrees of grafting onto plasticized PVC were higher than those onto pure one, at constant grafting conditions. The diffusibility of the monomer solution through the trunk polymers enhanced at higher monomer concentrations. The higher the monomer concentration the higher the degrees of grafting obtained. The dependence of the grafting rate on monomer concentration was found to be 0.15 and 0.4 order for the grafting onto pure and plasticized PVC films, respectively. The degree of grafting, at the higher irradiation doses, deviated from linearity and it tends to level off due to the recombination of some of the free radicals without initiating graft polymerization. Gel determination in the grafted films was investigated. The gel content in both grafted extracted pure and plasticized PVC films increased with the degree of grafting to reach a certain limiting values.

  7. International Federation of Societies for Surgery of the Hand Committee report: the role of nerve transfers in the treatment of neonatal brachial plexus palsy.

    PubMed

    Tse, Raymond; Kozin, Scott H; Malessy, Martijn J; Clarke, Howard M

    2015-06-01

    Nerve transfers have gained popularity in the treatment of adult brachial plexus palsy; however, their role in the treatment of neonatal brachial plexus palsy (NBPP) remains unclear. Brachial plexus palsies in infants differ greatly from those in adults in the patterns of injury, potential for recovery, and influences of growth and development. This International Federation of Societies for Surgery of the Hand committee report on NBPP is based upon review of the current literature. We found no direct comparisons of nerve grafting to nerve transfer for primary reconstruction of NBPP. Although the results contained in individual reports that use each strategy for treatment of Erb palsy are similar, comparison of nerve transfer to nerve grafting is limited by inconsistencies in outcomes reported, by multiple confounding factors, and by small numbers of patients. Although the role of nerve transfers for primary reconstruction remains to be defined, nerve transfers have been found to be effective and useful in specific clinical circumstances including late presentation, isolated deficits, failed primary reconstruction, and multiple nerve root avulsions. In the case of NBPP more severe than Erb palsy, nerve transfers alone are inadequate to address all of the deficits and should only be considered as adjuncts if maximal re-innervation is to be achieved. Surgeons who commit to care of infants with NBPP need to avoid an over-reliance on nerve transfers and should also have the capability and inclination for brachial plexus exploration and nerve graft reconstruction. PMID:25936735

  8. Mechanical properties of acellular mouse lungs after sterilization by gamma irradiation.

    PubMed

    Uriarte, Juan J; Nonaka, Paula N; Campillo, Noelia; Palma, Renata K; Melo, Esther; de Oliveira, Luis V F; Navajas, Daniel; Farré, Ramon

    2014-12-01

    Lung bioengineering using decellularized organ scaffolds is a potential alternative for lung transplantation. Clinical application will require donor scaffold sterilization. As gamma-irradiation is a conventional method for sterilizing tissue preparations for clinical application, the aim of this study was to evaluate the effects of lung scaffold sterilization by gamma irradiation on the mechanical properties of the acellular lung when subjected to the artificial ventilation maneuvers typical within bioreactors. Twenty-six mouse lungs were decellularized by a sodium dodecyl sulfate detergent protocol. Eight lungs were used as controls and 18 of them were submitted to a 31kGy gamma irradiation sterilization process (9 kept frozen in dry ice and 9 at room temperature). Mechanical properties of acellular lungs were measured before and after irradiation. Lung resistance (RL) and elastance (EL) were computed by linear regression fitting of recorded signals during mechanical ventilation (tracheal pressure, flow and volume). Static (Est) and dynamic (Edyn) elastances were obtained by the end-inspiratory occlusion method. After irradiation lungs presented higher values of resistance and elastance than before irradiation: RL increased by 41.1% (room temperature irradiation) and 32.8% (frozen irradiation) and EL increased by 41.8% (room temperature irradiation) and 31.8% (frozen irradiation). Similar increases were induced by irradiation in Est and Edyn. Scanning electron microscopy showed slight structural changes after irradiation, particularly those kept frozen. Sterilization by gamma irradiation at a conventional dose to ensure sterilization modifies acellular lung mechanics, with potential implications for lung bioengineering. PMID:25241281

  9. 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.

  10. 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

  11. 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

  12. Low-level laser therapy promotes the osteogenic potential of adipose-derived mesenchymal stem cells seeded on an acellular dermal matrix.

    PubMed

    Choi, Kyuseok; Kang, Byung-Jae; Kim, Hyoju; Lee, Seungmin; Bae, Sohee; Kweon, Oh-Kyeong; Kim, Wan Hee

    2013-08-01

    This study investigates the feasibility of using an adipose-derived mesenchymal stem cell (ASC)-seeded acellular dermal matrix (ADM) along with low-level laser therapy (LLLT) to repair bone defect in athymic nude mice. Critical-sized calvarial defects were treated either with ADM, ADM/LLLT, ADM/ASCs, or ADM/ASCs/LLLT. In micro-computed tomography scans, the ADM/ASCs and the ADM/ASCs/LLLT groups showed remarkable bone formation after 14 days. Additionally, bone regeneration in the ADM/ASCs/LLLT group was obvious at 28 days, but in the ADM/ASCs group at 56 days. Bone mineral density and bone tissue volume in the ADM/ASCs/LLLT group significantly increased after 7 days, but in the ADM/ASCs group after 14 days. Histological analysis revealed that the defects were repaired in the ADM/ASCs and the ADM/ASCs/LLLT group, while the defects in the ADM and the ADM/LLLT groups exhibited few bone islands at 28 and 56 days. The successful seeding of ASCs onto ADM was confirmed, and LLLT enhanced the proliferation and the survival of ASCs at 14 days. Our results indicate that ASC-seeded grafts promote bone regeneration, and the application of LLLT on ASC-seeded ADM results in rapid bone formation. The implantation of an ASC-seeded ADM combined with LLLT may be used effectively for bone regeneration.

  13. 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 ...

  14. 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

  15. Cryotherapy and nerve palsy.

    PubMed

    Drez, D; Faust, D C; Evans, J P

    1981-01-01

    Ice application is one of the most extensively used treatments for athletic injuries. Frostbite is a recognized danger. Five cases of nerve palsy resulting from ice application are reported here. These palsies were temporary. They usually resolve spontaneously without any significant sequelae. This complication can be avoided by not using ice for more than 30 minutes and by guarding superficial nerves in the area.

  16. Imaging the cranial nerves.

    PubMed

    Parry, Andrew T; Volk, Holger A

    2011-01-01

    An understanding of the normal course of the cranial nerves (CN) is essential when interpreting images of patients with cranial neuropathies. CN foramina are depicted best using computed X-ray tomography, but the nerves are depicted best using magnetic resonance imaging. The function and anatomy of the CN in the dog are reviewed and selected examples of lesions affecting the CN are illustrated.

  17. [Sciatic nerve intraneural perineurioma].

    PubMed

    Bonhomme, Benjamin; Poussange, Nicolas; Le Collen, Philippe; Fabre, Thierry; Vital, Anne; Lepreux, Sébastien

    2015-12-01

    Intraneural perineurioma is a benign tumor developed from the perineurium and responsible for localized nerve hypertrophy. This uncommon tumor is characterized by a proliferation of perineural cells with a "pseudo-onion bulb" pattern. We report a sciatic nerve intraneural perineurioma in a 39-year-old patient. PMID:26586011

  18. 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 ...

  19. [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

  20. Experimental assessment of the neo-vascularisation of acellular dermal matrix in the wound bed pretreated with mesenchymal stem cell under subatmospheric pressure.

    PubMed

    Sahin, Ismail; Ozturk, Sinan; Deveci, Mustafa; Ural, Ali Ugur; Onguru, Onder; Isik, Selcuk

    2014-01-01

    Neo-vascularisation of the acellular dermal matrix (ADM) is an essential procedure if a full-thickness wound is closed with ADM and skin is grafted over the ADM. In this study, we aimed to improve the neo-vascularisation of ADM by combining the effects of negative pressure wound therapy (NPWT) and mesenchymal stem cells (MSCs) on angiogenesis. In this study, 28 female Sprague-Dawley rats were used and divided into four groups. Full-thickness dorsal skin defects were created in 2 × 2 cm dimensions. The wounds were treated with only the ADM in group 1, the ADM and NPWT in group 2, the ADM and MSCs in group 3 and the ADM, NPWT and MSCs in group 4. By the ninth day of surgery, the excisional biopsy samples were histologically examined to identify the rates of ADM adherence to the recipient bed; the newly formed blood vessels which penetrate the ADM vertically and vascularisation were evaluated by immunohistochemical staining. The graft adherence rates were higher in group 4 than in the other groups statistically, p = 0.003. The numbers of cluster of differentiation 31 (CD31)-stained newly formed microvessels were higher in group 4 than in the other groups statistically, p < 0.05. All subjects in group 4 had the vertical vessels in normal calibration with open lumen vessels which penetrate the ADM. These findings suggest that MSC transplantation induces angiogenesis more efficiently than NPWT. The combination of the NPWT with MSC in this study has shown a synergistic effect on angiogenesis and has affected the neo-vascularisation of the ADM significantly.

  1. Acellular spinal cord scaffold seeded with mesenchymal stem cells promotes long-distance axon regeneration and functional recovery in spinal cord injured rats.

    PubMed

    Liu, Jia; Chen, Jian; Liu, Bin; Yang, Cuilan; Xie, Denghui; Zheng, Xiaochen; Xu, Song; Chen, Tianyu; Wang, Liang; Zhang, Zhongmin; Bai, Xiaochun; Jin, Dadi

    2013-02-15

    The stem cell-based experimental therapies are partially successful for the recovery of spinal cord injury (SCI). Recently, acellular spinal cord (ASC) scaffolds which mimic native extracellular matrix (ECM) have been successfully prepared. This study aimed at investigating whether the spinal cord lesion gap could be bridged by implantation of bionic-designed ASC scaffold alone and seeded with human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) respectively, and their effects on functional improvement. A laterally hemisected SCI lesion was performed in adult Sprague-Dawley (SD) rats (n=36) and ASC scaffolds seeded with or without hUCB-MSCs were implanted into the lesion immediately. All rats were behaviorally tested using the Basso-Beattie-Bresnahan (BBB) test once a week for 8weeks. Behavioral analysis showed that there was significant locomotor recovery improvement in combined treatment group (ASC scaffold and ASC scaffold+hUCB-MSCs) as compared with the SCI only group (p<0.01). 5-Bromodeoxyuridine (Brdu)-labeled hUCB-MSCs could also be observed in the implanted ACS scaffold two weeks after implantation. Moreover, host neural cells (mainly oligodendrocytes) were able to migrate into the graft. Biotin-dextran-amine (BDA) tracing test demonstrated that myelinated axons successfully grew into the graft and subsequently promoted axonal regeneration at lesion sites. This study provides evidence for the first time that ASC scaffold seeded with hUCB-MSCs is able to bridge a spinal cord cavity and promote long-distance axon regeneration and functional recovery in SCI rats.

  2. A biomechanical characterisation of acellular porcine super flexor tendons for use in anterior cruciate ligament replacement: investigation into the effects of fat reduction and bioburden reduction bioprocesses.

    PubMed

    Herbert, Anthony; Jones, Gemma L; Ingham, Eileen; Fisher, John

    2015-01-01

    The decellularisation of xenogenic and allogeneic biological grafts offers a promising solution to replacement of the anterior cruciate ligament (ACL). The purpose of this investigation was to determine the biomechanical effects of additional fat reduction and bioburden reduction steps in the decellularisation of porcine super flexor tendon (pSFT). Study 1 investigated the use of acetone or chloroform-methanol as a fat reduction agent. The most effective of these was then carried forward into Study 2, which investigated the use of antibiotics or peracetic acid (PAA) as a bioburden reduction agent. Stress relaxation data was analysed using a Maxwell-Wiechert viscoelastic model and, in addition to classical material properties, the tangent modulus of the toe-region was determined from strength testing data. In both studies, the majority of decellularised groups demonstrated no statistical differences for material properties such as tensile strength and Young's modulus compared to native controls. Different trends were observed for many of the viscoelastic parameters, but also for the tangent modulus in the toe-region indicating a change in performance at low strains. The most severe deviations from the profile of the native tangent modulus were found to occur in Study 2 when PAA was used for bioburden reduction. Classic material properties (E, UTS etc.) are often used to compare the characteristics of native and decellularised tissues, however they may not highlight changes occurring in the tissues at low strains. In this study, this represented the physiological strains encountered by substitute acellular ACL grafts. Acetone was chosen as the fat reduction step whereas, antibiotics was preferable over PAA as a bioburden reduction step. PMID:25443884

  3. Ulnar nerve tuberculoma.

    PubMed

    Ramesh Chandra, V V; Prasad, Bodapati Chandramowliswara; Varaprasad, Gangumolu

    2013-01-01

    The authors report a very rare case of tuberculoma involving the ulnar nerve. The patient, a 7-year-old girl, presented with swelling over the medial aspect of her right forearm just below the elbow joint, with features of ulnar nerve palsy, including paresthesias along the little and ring fingers and claw hand deformity. There was a history of trauma and contact with a contagious case of tuberculosis. There were no other signs of tuberculosis. At surgical exploration the ulnar nerve was found to be thickened, and on opening the sheath there was evidence of caseous material enclosed in a fibrous capsule compressing and displacing the nerve fibers. The lesion, along with the capsule, was subtotally removed using curettage, and a part of the capsule that was densely adherent to the nerve fibers was left in the patient. Histopathological examination of the specimen was consistent with tuberculoma. The patient received adequate antitubercular treatment and showed significant improvement.

  4. Peripheral nerve stimulation: definition.

    PubMed

    Abejón, David; Pérez-Cajaraville, Juan

    2011-01-01

    Recently, there has been a tremendous evolution in the field of neurostimulation, both from the technological point of view and from development of the new and different indications. In some areas, such as peripheral nerve stimulation, there has been a boom in recent years due to the variations in the surgical technique and the improved results documented by in multiple published papers. All this makes imperative the need to classify and define the different types of stimulation that are used today. The confusion arises when attempting to describe peripheral nerve stimulation and subcutaneous stimulation. Peripheral nerve stimulation, in its pure definition, involves implanting a lead on a nerve, with the aim to produce paresthesia along the entire trajectory of the stimulated nerve.

  5. An evaluation of serious neurological disorders following immunization: a comparison of whole-cell pertussis and acellular pertussis vaccines.

    PubMed

    Geier, David A; Geier, Mark R

    2004-08-01

    Serious neurological disorders reported following whole-cell pertussis in comparison to acellular pertussis vaccines were evaluated. The Vaccine Adverse Events Reporting System (VAERS) was analyzed for Emergency Department (ED) visits, life-threatening reactions, hospitalizations, disabilities, deaths, seizures, infantile spasms, encephalitis/encephalopathy, autism, Sudden Infant Death Syndrome (SIDS) and speech disorders reported with an initial onset of symptoms within 3 days following whole-cell pertussis and acellular pertussis vaccines among those residing in the US from 1997 to 1999. Controls were employed to evaluate potential biases in VAERS. Evaluations as to whether whole-cell and acellular vaccines were administered to populations of similar age and sex were undertaken because these factors might influence the study's results. Statistical increases were observed for all events examined following whole-cell pertussis vaccination in comparison to acellular pertussis vaccination, excepting cerebellar ataxia. Reporting biases were minimal in VAERS, and whole-cell and acellular pertussis vaccines were administered to populations of similar age and sex. Biologic mechanisms for the increased reactogenicity of whole-cell pertussis vaccines may stem from the fact that whole-cell pertussis vaccines contain 3,000 different proteins, whereas DTaP contains two to five proteins. Whole-cell pertussis vaccine contains known neurotoxins including: endotoxin, pertussis toxin and adenylate cyclase. Our results, and conclusions by the US Institute of Medicine, suggest an association between serious neurological disorders and whole-cell pertussis immunization. In light of the presence of a safer and at least equally efficacious acellular pertussis vaccine alternative, the Japanese and US switch to using acellular pertussis vaccine seems well justified. Other countries using whole-cell pertussis-containing vaccines should consider following suite in the near future.

  6. Bioactive poly(L-lactic acid) conduits seeded with Schwann cells for peripheral nerve regeneration.

    PubMed

    Evans, Gregory R D; Brandt, Keith; Katz, Steven; Chauvin, Priscilla; Otto, Lisa; Bogle, Melissa; Wang, Bao; Meszlenyi, Rudolph K; Lu, Lichun; Mikos, Antonios G; Patrick, Charles W

    2002-02-01

    This study attempted to enhance the efficacy of peripheral nerve regeneration using our previously tested poly(L-lactic acid) (PLLA) conduits by incorporating them with allogeneic Schwann cells (SCs). The SCs were harvested, cultured to obtain confluent monolayers and two concentrations (1 x 10(4) and 1 x 10(6) SC/ml) were combined with a collagen matrix (Vitrogen) and injected into the PLLA conduits. The conduits were then implanted into a 12 mm right sciatic nerve defect in rats. Three control groups were used: isografts, PLLA conduits filled with collagen alone and empty silicone tubes. The sciatic functional index (SFI) was calculated monthly through four months. At the end of second and fourth months, the gastrocnemius muscle was harvested and weighed for comparison and the graft conduit and distal nerve were harvested for histomorphologic analysis. The mean SFI demonstrated no group differences from isograft control. By four months, there was no significant difference in gastrocnemius muscle weight between the experimental groups compared to isograft controls. At four months, the distal nerve demonstrated a statistically lower number of axons mm2 for the high and low SC density groups and collagen control. The nerve fiber density was significantly lower in all of the groups compared to isograft controls by four months. The development of a "bioactive" nerve conduit using tissue engineering to replace autogenous nerve grafts offers a potential approach to improved patient care. Although equivalent nerve regeneration to autografts was not achieved, this study provides promising results for further investigation.

  7. Effects of a laminin peptide (YIGSR) immobilized on crab-tendon chitosan tubes on nerve regeneration.

    PubMed

    Itoh, Soichiro; Matsuda, Atsushi; Kobayashi, Hisatoshi; Ichinose, Shizuko; Shinomiya, Kenichi; Tanaka, Junzo

    2005-05-01

    Thiolated and nonthiolated hydroxyapatite-coated crab-tendon chitosan (t-chitosan/HAp-SH and t-chitosan/HAp, respectively) tubes, both alone and conjugated with CDPGYIGSR (YIGSR) peptide, were compared, in order to determine their biocompatibility and efficacy as nerve conduits. YIGSR peptide was adsorbed on the t-chitosan/HAp (HAp) tubes, and covalently bound on the t-chitosan/HAp-SH (HAp-SH) tubes (Y/HAp and Y/HAp-SH tubes, respectively). HAp, HAp-SH, Y/HAp, or Y/HAp-SH tubes measuring 15 mm were bridge grafted into the sciatic nerve of SD rats. Grafting of 15-mm-long Type I atelocollagen tubes and isografting of sciatic nerves were also carried out (N = 6 in each group). After 12 weeks, evoked muscle action potentials were recorded to calculate the terminal latency quotient. Histological observation and analysis of myelinated axons were also carried out. Nerve-tissue regeneration did not occur directly on the tubes' surfaces in the YIGSR peptide-unconjugated groups. Transplantation of YIGSR-conjugated tubes, however, gave rise to regenerated nerve tissue attached to thin layers of epineurium-like structure formed on the inner-tube surface. Histological and electrophysiological analyses suggested that although thiolation retards nerve-tissue regeneration, adsorbed YIGSR, and, to a lesser extent, peptide that had been covalently bound onto the tube surfaces, enhance nerve regeneration, promoting sprouting from the proximal nerve stump and bridging of regenerated axons throughout the tube.

  8. 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

  9. Purinergic nerves and receptors.

    PubMed

    Burnstock, G

    1980-01-01

    The presence of a non-cholinergic, non-adrenergic component in the vertebrate autonomic nervous system is now well established. Evidence that ATP is the transmitter released from some of these nerves (called "purinergic') includes: (a) synthesis and storage of ATP in nerves: (b) release of ATP from the nerves when they are stimulated; (c) exogenously applied ATP mimicking the action of nerve-released transmitter; (d) the presence of ectoenzymes which inactivate ATP; (e) drugs which produce similar blocking or potentiating effects on the response to exogenously applied ATP and nerve stimulation. A basis for distinguishing two types of purinergic receptors has been proposed according to four criteria: relative potencies of agonists, competitive antagonists, changes in levels of cAMP and induction of prostaglandin synthesis. Thus P1 purinoceptors are most sensitive to adenosine, are competitively blocked by methylxanthines and their occupation leads to changes in cAMP accumulation; while P2 purinoceptors are most sensitive to ATP, are blocked (although not competitively) by quinidine, 2-substituted imidazolines, 2,2'-pyridylisatogen and apamin, and their occupation leads to production of prostaglandin. P2 purinoceptors mediate responses of smooth muscle to ATP released from purinergic nerves, while P1 purinoceptors mediate the presynaptic actions of adenosine on adrenergic, cholinergic and purinergic nerve terminals. PMID:6108568

  10. 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.

  11. Intraparotid facial nerve neurofibroma.

    PubMed

    Sullivan, M J; Babyak, J W; Kartush, J M

    1987-02-01

    Neurogenic neoplasms of the intraparotid facial nerve are uncommon and are usually diagnosed intraoperatively by tissue biopsy. Fifty-six cases of primary neurogenic neoplasms involving the facial nerve have been reported. The majority of these have been schwannomas. A case of a solitary neurofibroma involving the main trunk of the facial nerve is presented. Schwannomas and neurofibromas have distinct histological features which must be considered prior to the management of these tumors. The management of neurogenic tumors associated with normal facial function is a particularly difficult problem. A new approach for the diagnosis and management of neurogenic neoplasms is described utilizing electroneurography. PMID:3807626

  12. 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

  13. Sciatic nerve repair with tissue engineered nerve: Olfactory ensheathing cells seeded poly(lactic-co-glygolic acid) conduit in an animal model

    PubMed Central

    Tan, C W; Ng, M H; Ohnmar, H; Lokanathan, Y; Nur-Hidayah, H; Roohi, S A; Ruszymah, BHI; Nor-Hazla, M H; Shalimar, A; Naicker, A S

    2013-01-01

    Background and Aim: Synthetic nerve conduits have been sought for repair of nerve defects as the autologous nerve grafts causes donor site morbidity and possess other drawbacks. Many strategies have been investigated to improve nerve regeneration through synthetic nerve guided conduits. Olfactory ensheathing cells (OECs) that share both Schwann cell and astrocytic characteristics have been shown to promote axonal regeneration after transplantation. The present study was driven by the hypothesis that tissue-engineered poly(lactic-co-glycolic acid) (PLGA) seeded with OECs would improve peripheral nerve regeneration in a long sciatic nerve defect. Materials and Methods: Sciatic nerve gap of 15 mm was created in six adult female Sprague-Dawley rats and implanted with PLGA seeded with OECs. The nerve regeneration was assessed electrophysiologically at 2, 4 and 6 weeks following implantation. Histopathological examination, scanning electron microscopic (SEM) examination and immunohistochemical analysis were performed at the end of the study. Results: Nerve conduction studies revealed a significant improvement of nerve conduction velocities whereby the mean nerve conduction velocity increases from 4.2 ΁ 0.4 m/s at week 2 to 27.3 ΁ 5.7 m/s at week 6 post-implantation (P < 0.0001). Histological analysis revealed presence of spindle-shaped cells. Immunohistochemical analysis further demonstrated the expression of S100 protein in both cell nucleus and the cytoplasm in these cells, hence confirming their Schwann-cell-like property. Under SEM, these cells were found to be actively secreting extracellular matrix. Conclusion: Tissue-engineered PLGA conduit seeded with OECs provided a permissive environment to facilitate nerve regeneration in a small animal model. PMID:24379458

  14. [Iatrogenic injuries of the facial nerve in the mastoid region].

    PubMed

    Príhodová, J; Zelený, M; Kozák, J

    1990-09-01

    During the past ten years nine patients were referred to our hospital with lesions of the VIIth nerve. These lesions were inflicted during operation on account of chronic otitis media. One patient recovered after conservative treatment. Based on the EMG examination and clinical picture, eight patients were operated. In one who had an extensive lesion it did not prove possible to find the proximal stump and the patient improved after Normann-Dott's operation. In the remaining seven subjects also severe damage was involved: five times complete severing of the nerve occurred, twice partial severing and contusion, always in the mastoid portion of the VIIth nerve. The authors achieved as a rule a 50-75% restoration of function of the VIIth nerve Ballance-Duel's operation, using a graft of the n. suralis with microsuture of the epineurium and gluing of the nerve by plasma. Evaluation of late functional results was made 1-8 years after Ballance-Duel's operation. The authors recommend to reduce the risk of iatrogenic lesions of the VIIth nerve in beginners by assistance of experienced surgeons at several operations. PMID:2225170

  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

    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

  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 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

  17. Corneal neurotization from the supratrochlear nerve with sural nerve grafts: a minimally invasive approach.

    PubMed

    Bains, Robert D; Elbaz, Uri; Zuker, Ronald M; Ali, Asim; Borschel, Gregory H

    2015-02-01

    Corneal anesthesia is a debilitating condition which can ultimately lead to blindness from repetitive corneal injury and scarring. We have developed a minimally invasive technique for corneal re-innervation that we have used with excellent results in ten eyes. This article and accompanying video describes the relevant anatomy and demonstrates the technique in detail.

  18. Development of a nerve scaffold using a tendon chitosan tube.

    PubMed

    Itoh, Soichiro; Suzuki, Masumi; Yamaguchi, Isamu; Takakuda, Kazuo; Kobayashi, Hisatoshi; Shinomiya, Kenichi; Tanaka, Junzo

    2003-12-01

    Bridge grafting (15 mm) into the sciatic nerve of SD rats was carried out using tendon chitosan tubes having either a circular or triangular cross-section, as well as triangular tubes combined with laminin, CDPGYIGSR, or CSRARKQAASIKVAVSAD (n = 15 in each group). As a control, isografting (15 mm) was carried out in the SD rats (n = 7). Specimens were taken after 1, 2, 4, 6, and 8 weeks for histology, and nerve regeneration was evaluated electro-physiologically and histologically after 12 weeks. The mechanical strength of triangular tubes was found to be higher than circular tubes, and the inner volume of a triangular tube tends to be larger than in circular tubes. Nerve tissue regeneration along the tube wall was found in both the laminin and laminin peptide groups. According to the result of percentage neural tissue in relation to evoked action potentials, the consecutive treatments of YIGSR and IKVAV was found to match the effectiveness of intact laminin.

  19. Mechanisms of Fat Graft Survival.

    PubMed

    Pu, Lee L Q

    2016-02-01

    Although more fat grafting procedures have been performed by plastic surgeons with the primary goal to restore soft tissue loss, the actual mechanism on how fat graft survives remains less completely understood. An established old theory on fat graft survival is still based on the cell survival theory proposed by Peer in the early 1950s. On the basis of his preliminary experimental study, he proposed that the mechanism of fat graft survival is based on established early blood circulation through anastomosis of the fat graft and host blood vessels. Recently, several investigators have demonstrated new concepts of the fat graft survival: One further advanced the old Peer cell survival theory and another based on new discovery and understanding of adipose-derived stem cells. This article serves as a scientific review on how fat graft survives after in vivo transplantation based on a number of well-conducted experimental studies. Both the graft survival and graft replacement theories on how fat graft survives are true based on the previously mentioned well-conducted experimental studies. Each theory may play a role in fat graft survival. It is possible that graft survival may be more dominant in some patients but the graft replacement may be more dominant in other patients.

  20. Diabetes and nerve damage

    MedlinePlus

    Diabetic neuropathy; Diabetes - neuropathy; Diabetes - peripheral neuropathy ... In people with diabetes, the body's nerves can be damaged by decreased blood flow and a high blood sugar level. This condition is ...

  1. Vagus Nerve Stimulation

    PubMed Central

    Howland, Robert H.

    2014-01-01

    The vagus nerve is a major component of the autonomic nervous system, has an important role in the regulation of metabolic homeostasis, and plays a key role in the neuroendocrine-immune axis to maintain homeostasis through its afferent and efferent pathways. Vagus nerve stimulation (VNS) refers to any technique that stimulates the vagus nerve, including manual or electrical stimulation. Left cervical VNS is an approved therapy for refractory epilepsy and for treatment resistant depression. Right cervical VNS is effective for treating heart failure in preclinical studies and a phase II clinical trial. The effectiveness of various forms of non-invasive transcutaneous VNS for epilepsy, depression, primary headaches, and other conditions has not been investigated beyond small pilot studies. The relationship between depression, inflammation, metabolic syndrome, and heart disease might be mediated by the vagus nerve. VNS deserves further study for its potentially favorable effects on cardiovascular, cerebrovascular, metabolic, and other physiological biomarkers associated with depression morbidity and mortality. PMID:24834378

  2. Sacral nerve stimulation.

    PubMed

    Matzel, K E; Stadelmaier, U; Besendörfer, M

    2004-01-01

    The current concept of recruiting residual function of an inadequate pelvic organ by electrostimulation involves stimulation of the sacral spinal nerves at the level of the sacral canal. The rationale for applying SNS to fecal incontinence was based on clinical observations of its effect on bowel habits and anorectal continence function in urologic patients (increased anorectal angulation and anal canal closure pressure) and on anatomic considerations: dissection demonstrated a dual peripheral nerve supply of the striated pelvic floor muscles that govern these functions. Because the sacral spinal nerve site is the most distal common location of this dual nerve supply, stimulating here can elicit both functions. Since the first application of SNS in fecal incontinence in 1994, this technique has been improved, the patient selection process modified, and the spectrum of indications expanded. At present SNS has been applied in more than 1300 patients with fecal incontinence limited.

  3. 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 ...

  4. Damaged axillary nerve (image)

    MedlinePlus

    Conditions associated with axillary nerve dysfunction include fracture of the humerus (upper arm bone), pressure from casts or splints, and improper use of crutches. Other causes include systemic disorders that cause neuritis (inflammation of ...

  5. Iatrogenic accessory nerve injury.

    PubMed Central

    London, J.; London, N. J.; Kay, S. P.

    1996-01-01

    Accessory nerve injury produces considerable disability. The nerve is most frequently damaged as a complication of radical neck dissection, cervical lymph node biopsy and other surgical procedures. The problem is frequently compounded by a failure to recognise the error immediately after surgery when surgical repair has the greatest chance of success. We present cases which outline the risk of accessory nerve injury, the spectrum of clinical presentations and the problems produced by a failure to recognise the deficit. Regional anatomy, consequences of nerve damage and management options are discussed. Diagnostic biopsy of neck nodes should not be undertaken as a primary investigation and, when indicated, surgery in this region should be performed by suitably trained staff under well-defined conditions. Awareness of iatrogenic injury and its consequences would avoid delays in diagnosis and treatment. Images Figure 2 PMID:8678450

  6. 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 ...

  7. 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 ...

  8. 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

  9. Lower cranial nerves.

    PubMed

    Soldatos, Theodoros; Batra, Kiran; Blitz, Ari M; Chhabra, Avneesh

    2014-02-01

    Imaging evaluation of cranial neuropathies requires thorough knowledge of the anatomic, physiologic, and pathologic features of the cranial nerves, as well as detailed clinical information, which is necessary for tailoring the examinations, locating the abnormalities, and interpreting the imaging findings. This article provides clinical, anatomic, and radiological information on lower (7th to 12th) cranial nerves, along with high-resolution magnetic resonance images as a guide for optimal imaging technique, so as to improve the diagnosis of cranial neuropathy.

  10. 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

  11. Graft-versus-host disease

    MedlinePlus

    GVHD; Bone marrow transplant - graft-versus-host disease; Stem cell transplant - graft-versus-host disease; Allogeneic transplant - ... GVHD may occur after a bone marrow, or stem cell, transplant in which someone receives bone marrow ...

  12. Adipose tissue regeneration in vivo using micronized acellular allogenic dermis as an injectable scaffold.

    PubMed

    Lee, Hee Young; Yang, Hyun Jin; Rhie, Jong Won; Han, Ki Talk

    2014-10-01

    Over the past few years, the clinical use of injectable artificial materials in plastic surgery has increased. In addition, autologous lipoimplantation is being performed for volume replacement of soft tissue for aesthetic purposes. In this study, acellular allogenic dermis was utilized as a scaffold for the culturing of preadipocytes, confirming the possibility of three-dimensional proliferation of progenitor cells, the eventual differentiation of stromal cells in adipose tissue into the adipocytes, and the in vivo implantation of such adipocytes to form fat tissue. Preadipocytes, recently called ASCs (adipose tissue-derived stromal/stem cells), were cultured in acellular allogenic dermis, successfully attached to the dermal particles in a three-dimensional structure, and proliferated, differentiated, and eventually formed a cluster. For the in vivo implantation, four groups were formed: the first group was cultured within the dermal scaffold for 24 h before implantation (24-h preconditioned group), the second group was induced for differentiation for 10 days before implantation (10-day preconditioned group), the third group was implanted immediately after cell propagation (nonpreconditioned group), and the control group was implanted with only dermal scaffold. In vivo implanted preadipocytes showed great differentiation into adipocytes within the dermal scaffolds. Also, the 10-day preconditioned group showed a greater volume of fat tissue compared to the 24-h preconditioned group. From these results, we confirmed that after a three-dimensional culture in acellular allogenic dermis, implanted preadipocytes formed a greater amount of fat tissue and that this could be a possible effective method for future soft tissue restoration.

  13. 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

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

    PubMed Central

    Vu, Michael M.

    2015-01-01

    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

  15. Grafting effects on vegetable quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the United States, vegetable grafting is rare and few experiments have been done to determine optimal grafting procedures and production practices for different geographical and climatic regions in America. Grafting vegetables to control soilborne disease is a common practice in Asia, parts of E...

  16. Contralateral C7 nerve root transfer in treatment of cerebral palsy in a child: case report.

    PubMed

    Xu, Wen-Dong; Hua, Xu-Yun; Zheng, Mou-Xiong; Xu, Jian-Guang; Gu, Yu-Dong

    2011-07-01

    A 4-year-old girl who sustained the hemiplegic cerebral palsy and subsequent spasticity in the left upper extremity underwent the C7 nerve root rhizotomy and the contralateral C7 nerve root transfer to the ipsilateral middle trunk of brachial plexus through an interpositional sural nerve graft. In a 2-year follow-up, the results showed a reduction in spasticity and an improvement in extension power of the elbow, the wrist, and the second to fifth fingers. Scores from both Quality of Upper Extremity Skills Test and Modified Ashworth Scale tests had been significantly improved during follow-up. The outcomes from this case provided the evidence that combined the C7 nerve root rhizotomy and contralateral healthy C7 nerve root transfer to the ipsilateral middle trunk of brachial plexus not only partially released flexional spasticity but also strengthened extension power of the spastic upper extremity in children with the cerebral palsy. PMID:21503970

  17. 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

  18. 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...

  19. Acrylonitrile grafted to PVDF

    DOEpatents

    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.

  20. Vascular graft infections.

    PubMed

    Hasse, Barbara; Husmann, Lars; Zinkernagel, Annelies; Weber, Rainer; Lachat, Mario; Mayer, Dieter

    2013-01-01

    Vascular procedures are rarely complicated by infection, but if prosthetic vascular graft infection (PVGI) occurs, morbidity and mortality are high. Several patient-related, surgery-related and postoperative risk factors are reported, but they are not well validated. PVGI is due to bacterial colonisation of the wound and the underlying prosthetic graft, generally as a result of direct contamination during the operative procedure, mainly from the patient's skin or adjacent bowel. There is no consensus on diagnostic criteria or on the best management of PVGI. On the basis of reported clinical studies and our own experience, we advocate a surgical approach combining repeated radical local debridement, with graft preservation whenever possible or partial excision of the infected graft, depending on its condition, plus simultaneous negative-pressure wound therapy (NPWT). In addition, antimicrobial therapy is recommended, but there is no consensus on which classes of agent are adequate for the treatment of PVGI and whether certain infections may be treated by means of NPWT alone. Since staphylococci and Gram-negative rods are likely to be isolated, empirical treatment might include a penicillinase-resistant beta-lactam or a glycopeptide, plus an aminoglycoside, the latter for Gram-negative coverage and synergistic treatment of Gram-positive cocci. Additionally, empirical treatment might include rifampicin since it penetrates well into biofilms.

  1. Communications Between the Facial Nerve and the Vestibulocochlear Nerve, the Glossopharyngeal Nerve, and the Cervical Plexus.

    PubMed

    Hwang, Kun; Song, Ju Sung; Yang, Su Cheol

    2015-10-01

    The aim of this review is to elucidate the communications between the facial nerves or facial nerve and neighboring nerves: the vestibulocochlear nerve, the glossopharyngeal nerve, and the cervical plexus.In a PubMed search, 832 articles were searched using the terms "facial nerve and communication." Sixty-two abstracts were read and 16 full-text articles were reviewed. Among them, 8 articles were analyzed.The frequency of communication between the facial nerve and the vestibulocochlear nerve was the highest (82.3%) and the frequency of communication between the facial nerve and the glossopharyngeal nerve was the lowest (20%). The frequency of communication between the facial nerve and the cervical plexus was 65.2 ± 43.5%. The frequency of communication between the cervical branch and the marginal mandibular branch of the facial nerve was 24.7 ± 1.7%.Surgeons should be aware of the nerve communications, which are important during clinical examinations and surgical procedures of the facial nerves such as those communications involved in facial reconstructive surgery, neck dissection, and various nerve transfer procedures.

  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. Biomedical engineering strategies for peripheral nerve repair: surgical applications, state of the art, and future challenges.

    PubMed

    Pfister, Bryan J; Gordon, Tessa; Loverde, Joseph R; Kochar, Arshneel S; Mackinnon, Susan E; Cullen, D Kacy

    2011-01-01

    Damage to the peripheral nervous system is surprisingly common and occurs primarily from trauma or a complication of surgery. Although recovery of nerve function occurs in many mild injuries, outcomes are often unsatisfactory following severe trauma. Nerve repair and regeneration presents unique clinical challenges and opportunities, and substantial contributions can be made through the informed application of biomedical engineering strategies. This article reviews the clinical presentations and classification of nerve injuries, in addition to the state of the art for surgical decision-making and repair strategies. This discussion presents specific challenges that must be addressed to realistically improve the treatment of nerve injuries and promote widespread recovery. In particular, nerve defects a few centimeters in length use a sensory nerve autograft as the standard technique; however, this approach is limited by the availability of donor nerve and comorbidity associated with additional surgery. Moreover, we currently have an inadequate ability to noninvasively assess the degree of nerve injury and to track axonal regeneration. As a result, wait-and-see surgical decisions can lead to undesirable and less successful "delayed" repair procedures. In this fight for time, degeneration of the distal nerve support structure and target progresses, ultimately blunting complete functional recovery. Thus, the most pressing challenges in peripheral nerve repair include the development of tissue-engineered nerve grafts that match or exceed the performance of autografts, the ability to noninvasively assess nerve damage and track axonal regeneration, and approaches to maintain the efficacy of the distal pathway and targets during the regenerative process. Biomedical engineering strategies can address these issues to substantially contribute at both the basic and applied levels, improving surgical management and functional recovery following severe peripheral nerve injury.

  4. 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

  5. Xenogeneic acellular conjunctiva matrix as a scaffold of tissue-engineered corneal epithelium.

    PubMed

    Zhao, Haifeng; Qu, Mingli; Wang, Yao; Wang, Zhenyu; Shi, Weiyun

    2014-01-01

    Amniotic membrane-based tissue-engineered corneal epithelium has been widely used in the reconstruction of the ocular surface. However, it often degrades too early to ensure the success of the transplanted corneal epithelium when treating patients with severe ocular surface disorders. In the present study, we investigated the preparation of xenogeneic acellular conjunctiva matrix (aCM) and evaluated its efficacy and safety as a scaffold of tissue-engineered corneal epithelium. Native porcine conjunctiva was decellularized with 0.1% sodium dodecyl sulfate (SDS) for 12 h at 37°C and sterilized via γ-irradiation. Compared with native conjunctiva, more than 92% of the DNA was removed, and more than 90% of the extracellular matrix components (glycosaminoglycan and collagen) remained after the decellularization treatment. Compared with denuded amniotic membrane (dAM), the aCM possessed favorable optical transmittance, tensile strength, stability and biocompatibility as well as stronger resistance to degradation both in vitro and in vivo. The corneal epithelial cells seeded on aCM formed a multilayered epithelial structure and endured longer than did those on dAM. The aCM-based tissue-engineered corneal epithelium was more effective in the reconstruction of the ocular surface in rabbits with limbal stem cell deficiency. These findings support the application of xenogeneic acellular conjunctiva matrix as a scaffold for reconstructing the ocular surface.

  6. 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

  7. The acellular matrix (ACM) for bladder tissue engineering: A quantitative magnetic resonance imaging study.

    PubMed

    Cheng, Hai-Ling Margaret; Loai, Yasir; Beaumont, Marine; Farhat, Walid A

    2010-08-01

    Bladder acellular matrices (ACMs) derived from natural tissue are gaining increasing attention for their role in tissue engineering and regeneration. Unlike conventional scaffolds based on biodegradable polymers or gels, ACMs possess native biomechanical and many acquired biologic properties. Efforts to optimize ACM-based scaffolds are ongoing and would be greatly assisted by a noninvasive means to characterize scaffold properties and monitor interaction with cells. MRI is well suited to this role, but research with MRI for scaffold characterization has been limited. This study presents initial results from quantitative MRI measurements for bladder ACM characterization and investigates the effects of incorporating hyaluronic acid, a natural biomaterial useful in tissue-engineering and regeneration. Measured MR relaxation times (T(1), T(2)) and diffusion coefficient were consistent with increased water uptake and glycosaminoglycan content observed on biochemistry in hyaluronic acid ACMs. Multicomponent MRI provided greater specificity, with diffusion data showing an acellular environment and T(2) components distinguishing the separate effects of increased glycosaminoglycans and hydration. These results suggest that quantitative MRI may provide useful information on matrix composition and structure, which is valuable in guiding further development using bladder ACMs for organ regeneration and in strategies involving the use of hyaluronic acid.

  8. 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

  9. Waning vaccine immunity in teenagers primed with whole cell and acellular pertussis vaccine: recent epidemiology.

    PubMed

    Sheridan, Sarah L; Frith, Katie; Snelling, Thomas L; Grimwood, Keith; McIntyre, Peter B; Lambert, Stephen B

    2014-09-01

    The recent epidemics of pertussis (whooping cough) in parts of the USA and Australia have led to the largest numbers of annual cases reported in over half a century. These epidemics demonstrated a new pattern, with particularly high rates of disease among pre-adolescents and early adolescents. These high rates of pertussis coincided with the first cohorts vaccinated with purely acellular pertussis vaccine, which replaced whole-cell pertussis (wP) vaccine in the later 1990s in the USA and Australia. Studies undertaken during these epidemics provide new evidence of more rapid waning of acellular pertussis-containing vaccines and longer-term protection from effective wP-containing vaccines. There is evidence that receiving wP as at least the first dose of pertussis-containing vaccine provides greater and more long-lived protection, irrespective of the nature of subsequent doses. This evidence will be reviewed together with the immunobiology associated with both vaccines, and the implications for pertussis control discussed. PMID:25093268

  10. 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

  11. Neuromuscular ultrasound of cranial nerves.

    PubMed

    Tawfik, Eman A; Walker, Francis O; Cartwright, Michael S

    2015-04-01

    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.

  12. 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

  13. 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

  14. [Effect of embryonic anlage allografts of the rat spinal cord on growth of regenerating fibers of the recipient nerve].

    PubMed

    Petrova, E S; Isaeva, E N

    2014-01-01

    A comparative study of the effect of tissue and suspension allografts of an embryonic spinal cord on regeneration of nerve fibers of impaired (by application of a ligature) sciatic nerve in rats was conducted. It was demonstrated that unlike tissue grafts that reach a large volume 21 and 60 days after transplantation, suspension grafts do not inhibit the growth of axons of the recipient to the periphery. It was established that introduction of a suspension of dissociated cells of the spinal cord embryonic anlages (but not fragments of these anlages) into the impaired sciatic nerve in rats results in an increase in the amount of myelinated regenerating nerve fibers of the recipient 60 days after the operation.

  15. Processed allografts and type I collagen conduits for repair of peripheral nerve gaps.

    PubMed

    Whitlock, Elizabeth L; Tuffaha, Sami H; Luciano, Janina P; Yan, Ying; Hunter, Daniel A; Magill, Christina K; Moore, Amy M; Tong, Alice Y; Mackinnon, Susan E; Borschel, Gregory H

    2009-06-01

    Autografting is the gold standard in the repair of peripheral nerve injuries that are not amenable to end-to-end coaptation. However, because autografts result in donor-site defects and are a limited resource, an effective substitute would be valuable. In a rat model, we compared isografts with Integra NeuraGen (NG) nerve guides, which are a commercially available type I collagen conduit, with processed rat allografts comparable to AxoGen's Avance human decellularized allograft product. In a 14-mm sciatic nerve gap model, isograft was superior to processed allograft, which was in turn superior to NG conduit at 6 weeks postoperatively (P < 0.05 for number of myelinated fibers both at midgraft and distal to the graft). At 12 weeks, these differences were no longer apparent. In a 28-mm graft model, isografts again performed better than processed allografts at both 6 and 22 weeks; regeneration through the NG conduit was often insufficient for analysis in this long graft model. Functional tests confirmed the superiority of isografts, although processed allografts permitted successful reinnervation of distal targets not seen in the NG conduit groups. Processed allografts were inherently non-immunogenic and maintained some internal laminin structure. We conclude that, particularly in a long gap model, nerve graft alternatives fail to confer the regenerative advantages of an isograft. However, AxoGen processed allografts are superior to a currently available conduit-style nerve guide, the Integra NeuraGen. They provide an alternative for reconstruction of short nerve gaps where a conduit might otherwise be used.

  16. 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

  17. 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.

  18. 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.

  19. Peripheral nerve response to injury.

    PubMed

    Steed, Martin B

    2011-03-01

    Oral and maxillofacial surgeons caring for patients who have sustained a nerve injury to a branch of the peripheral trigeminal nerve must possess a basic understanding of the response of the peripheral nerves to trauma. The series of events that subsequently take place are largely dependent on the injury type and severity. Regeneration of the peripheral nerve is possible in many instances and future manipulation of the regenerative microenvironment will lead to advances in the management of these difficult injuries.

  20. Human Acellular Dermis versus Submuscular Tissue Expander Breast Reconstruction: A Multivariate Analysis of Short-Term Complications

    PubMed Central

    Davila, Armando A.; Seth, Akhil K.; Wang, Edward; Hanwright, Philip; Bilimoria, Karl; Fine, Neil

    2013-01-01

    Background Acellular dermal matrix (ADM) allografts and their putative benefits have been increasingly described in prosthesis based breast reconstruction. There have been a myriad of analyses outlining ADM complication profiles, but few large-scale, multi-institutional studies exploring these outcomes. In this study, complication rates of acellular dermis-assisted tissue expander breast reconstruction were compared with traditional submuscular methods by evaluation of the American College of Surgeon's National Surgical Quality Improvement Program (NSQIP) registry. Methods Patients who underwent immediate tissue expander breast reconstruction from 2006-2010 were identified using surgical procedure codes. Two hundred forty tracked variables from over 250 participating sites were extracted for patients undergoing acellular dermis-assisted versus submuscular tissue expander reconstruction. Thirty-day postoperative outcomes and captured risk factors for complications were compared between the two groups. Results A total of 9,159 patients underwent tissue expander breast reconstruction; 1,717 using acellular dermis and 7,442 with submuscular expander placement. Total complications and reconstruction related complications were similar in both cohorts (5.5% vs. 5.3%, P=0.68 and 4.7% vs. 4.3%, P=0.39, respectively). Multivariate logistic regression revealed body mass index and smoking as independent risk factors for reconstructive complications in both cohorts (P<0.01). Conclusions The NSQIP database provides large-scale, multi-institutional, independent outcomes for acellular dermis and submuscular breast reconstruction. Both thirty-day complication profiles and risk factors for post operative morbidity are similar between these two reconstructive approaches. PMID:23362476

  1. 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…

  2. 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 ...

  3. Extension of synaptic extracellular matrix during nerve terminal sprouting in living frog neuromuscular junctions.

    PubMed

    Chen, L; Ko, C P

    1994-02-01

    Remodeling of the synaptic extracellular matrix (ECM) and its dynamic relationship with nerve terminal plasticity have been demonstrated in normal frog neuromuscular junctions (NMJs) in vivo (Chen et al., 1991). Our previous work has led to a hypothesis that extension of synaptic ECM precedes nerve terminal growth during synaptic remodeling. To test this hypothesis, the present study examined the changes of synaptic ECM in frog NMJs that were primarily undergoing nerve terminal growth and sprouting. Frog sartorius muscles were double stained with a fluorescent nerve terminal dye (4-Di-2-Asp) and rhodamine-tagged peanut agglutinin (PNA), which recognizes synaptic ECM. The double-labeled NMJs were visualized in vivo with video-enhanced fluorescence microscopy. Nerve sprouting was then induced in the muscle by grafting segments of the contralateral sciatic nerve. The identified NMJs were restrained and reexamined 2-3 months later. Extensive sprouting was observed in 46% of 167 identified NMJs. At junctional regions that showed extension or formation of new branches, synaptic ECM was commonly seen to have the same shape and distribution as the nerve terminal. However, extension of synaptic ECM beyond the corresponding nerve terminals, often by tens of microns, was observed in 29% of these newly formed junctional regions. This lack of correlation might be transient, as growth of nerve terminals following extended, PNA-stained ECM was seen. Examination with histological staining not only confirmed a lack of nerve terminal at the extended synaptic ECM region but also indicated an absence of AChE and postsynaptic junctional folds. The absence of these postsynaptic specializations at the extended, PNA-stained ECM region makes it unlikely that this region was previously occupied by nerve terminals that had retracted. Thus, the present study provides further findings consistent with the hypothesis that synaptic ECM precedes nerve terminal outgrowth and that the extension of

  4. Strategy and timing of peripheral nerve surgery.

    PubMed

    Brunelli, G; Brunelli, F

    1990-01-01

    The authors review the latest theories of peripheral nerve regeneration and repair. They present their research on nerve regeneration including the alterations in the mother cell body, and in the distal part of the axon, and the time required to reach the best production of amino acids for cytoskeleton reconstruction. Other research of particular interest which is presented regards the chemotactic arrangement of motor and sensory axons inside a vein. This research has shown that the axons are able to find their way to the appropriate (sensory or motor) distal endoneural tubes. Adoption phenomena are also presented. The discussion of surgery includes the type (suture, glueing, grafts, tubulization) and the time of surgical repair. Timing and repair strategies are related to the site of the lesion (which can require that a greater or smaller amount of cytoskeleton be reconstructed), the type of the injury, the state of surrounding tissues, the age of the patients, injuries to muscles, tendons, bones, vessels and skin. A scheme of strategy is proposed. PMID:2187163

  5. [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

  6. [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.

  7. The masseteric nerve: a versatile power source in facial animation techniques.

    PubMed

    Bianchi, B; Ferri, A; Ferrari, S; Copelli, C; Salvagni, L; Sesenna, E

    2014-03-01

    The masseteric nerve has many advantages including low morbidity, its proximity to the facial nerve, the strong motor impulse, its reliability, and the fast reinnervation that is achievable in most patients. Reinnervation of a neuromuscular transplant is the main indication for its use, but it has been used for the treatment of recent facial palsies with satisfactory results. We have retrospectively evaluated 60 patients who had facial animation procedures using the masseteric nerve during the last 10 years. The patients included those with recent, and established or congenital, unilateral and bilateral palsies. The masseteric nerve was used for coaptation of the facial nerve either alone or in association with crossfacial nerve grafting, or for the reinnervation of gracilis neuromuscular transplants. Reinnervation was successful in all cases, the mean (range) time being 4 (2-5) months for facial nerve coaptation and 4 (3-7) months for neuromuscular transplants. Cosmesis was evaluated (moderate, n=10, good, n=30, and excellent, n=20) as was functional outcome (no case of impairment of masticatory function, all patients able to smile, and achievement of a smile independent from biting). The masseteric nerve has many uses, including in both recent, and established or congenital, cases. In some conditions it is the first line of treatment. The combination of combined techniques gives excellent results in unilateral palsies and should therefore be considered a valid option.

  8. 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.

  9. 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.

  10. Tetanus-diphtheria-acellular pertussis vaccination of adults in the USA.

    PubMed

    Gidengil, Courtney A; Sandora, Thomas J; Lee, Grace M

    2008-07-01

    Pertussis is an important cause of morbidity and mortality, and its incidence has been increasing in adolescents and adults over the past two decades. Waning immunity in adolescents and adults may be partially responsible. Adults can suffer significant illness from pertussis and its complications, such as pneumonia, rib fractures and syncope. Moreover, adults serve as a source of disease for infants, who are more vulnerable to severe complications and even death. The economic burden of pertussis is substantial, in terms of both medical and nonmedical costs. Fortunately, the burden of pertussis disease can now be safely and effectively reduced by vaccinating adults with tetanus-diphtheria-acellular pertussis (Tdap) vaccine. Further research is needed to elucidate the role of vaccination in pregnant women and those over 65 years of age, and also to determine whether further booster doses of Tdap are needed.

  11. Immune Responses to Pertussis Antigens in Infants and Toddlers after Immunization with Multicomponent Acellular Pertussis Vaccine

    PubMed Central

    Wang, Li; Chen, Qingxia

    2014-01-01

    Given the resurgence of pertussis despite high rates of vaccination with the diphtheria-tetanus-acellular pertussis (DTaP) vaccine, a better understanding of vaccine-induced immune responses to Bordetella pertussis is needed. We investigated the antibody, cell-mediated, and cytokine responses to B. pertussis antigens in children who received the primary vaccination series (at 2, 4, and 6 months) and first booster vaccination (at 15 to 18 months) with 5-component acellular pertussis (aP) vaccine. The majority of subjects demonstrated a 4-fold increase in antibody titer to all four pertussis antigens (pertussis toxin [PT], pertactin [PRN], filamentous hemagglutinin [FHA], and fimbriae [FIM]) following the primary series and booster vaccination. Following the primary vaccine series, the majority of subjects (52 to 67%) mounted a positive T cell proliferative response (stimulation index of ≥3) to the PT and PRN antigens, while few subjects (7 to 12%) mounted positive proliferative responses to FHA and FIM. One month after booster vaccination (age 16 to 19 months), our study revealed significant increase in gamma interferon (IFN-γ) production in response to the PT and FIM antigens, a significant increase in IL-2 production with the PT, FHA, and PRN antigens, and a lack of significant interleukin-4 (IL-4) secretion with any of the antigens. While previous reports documented a mixed Th1/Th2 or Th2-skewed response to DTaP vaccine in children, our data suggest that following the first DTaP booster, children aged 16 to 19 months have a cytokine profile consistent with a Th1 response, which is known to be essential for clearance of pertussis infection. To better define aP-induced immune responses following the booster vaccine, further studies are needed to assess cytokine responses pre- and postbooster in DTaP recipients. PMID:25253666

  12. 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

  13. 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

  14. 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

  15. Behavioral evaluation of hemiparkinsonian MPTP monkeys following dopamine pharmacological manipulation and adrenal co-graft transplantation.

    PubMed

    Howel, L L; Byrd, L D; McDonough, A M; Iuvone, P M; Bakay, R A

    2000-01-01

    Bradykinesia and rigidity are the symptoms that most directly correlate with loss of striatal dopamine in Parkinson's disease. In the hemiparkinsonian (HP) monkey, this is represented by paucity of movement as measured by coli puterized movement analysis, diminished manual dexterity on clinical examination, and diminished performance on operant behavioral tasks. The present study used an MPTP-induced HP model in rhesus monkeys to evaluate the effectiveness of adrenal medullary and peripheral nerve co-grafts in diminishing parkinsonian symptoms. Unoperated controls (N = 4), surgical controls with caudate lesioning (N = 4), and caudate co-grafted (N = 4) HP monkeys demonstrated diminished movement in the home cage following MPTP. This behavior persisted in unoperated controls, but improved in both surgical control and co-grafted monkeys. Functional hand dexterity evaluations demonstrated similar impairment in all three groups but only surgical controls and co-grafted monkeys demonstrated improvement. In general, rotational behavior in response to apomorphine was consistent with recovery of function in surgical controls and co grafted monkeys, but marked between-subject variability precluded group statistical analyses. None of the monkeys could perform the operant task using the affected limb following MPTP. However, the performance of two co-grafted animals demonstrated partial recovery. L-dopa improved operant performance, demonstrating a dopaminergic component to the task. The results demonstrate recovery of behavioral function after surgical treatment, with adrenal co-grafted monkeys showing the greatest degree of improvement. PMID:11144958

  16. 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

  17. 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

  18. 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

  19. 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

  20. [Suprascapular nerve entrapment].

    PubMed

    Fansa, H; Schneider, W

    2003-03-01

    Isolated compression of the suprascapular nerve is a rare entity, that is seldom considered in differential diagnosis of shoulder pain. Usually atrophy of supraspinatus and infraspinatus muscles is present, resulting in weakened abduction and external rotation of the shoulder. Mostly the patients do not note the paresis, but complain about a dull and burning pain over the dorsal shoulder region. In a proximal lesion (at level of the superior transverse scapular ligament) electromyography reveals changes in both muscles, while in a distal lesion (spinoglenoidal notch) only the infraspinatus shows a pathology. From 1996 to 2001 we diagnosed an isolated suprascapular entrapment in nine patients. Seven patients were operated: The ligament was removed and the nerve was neurolysed. The average age was 36 years. All patients showed pathological findings in electrophysiological and clinical examination. Five patients had an atrophy of both scapula muscles, two showed only infraspinatus muscle atrophy (one with a ganglion in the distal course of the nerve). Six patients were followed up. All showed an improvement. Pain disappeared and all patients were able to return to work and sport activities. Electrophysiological examination one year after operation revealed normal nerve conduction velocity. The number of motor units, however, showed a reduction by half compared to the healthy side. Lesions without history of trauma are usually caused by repetitive motion or posture. Weight lifting, volley ball and tennis promote the entrapment. Rarely a lesion (either idiopathic or due to external compression) is described for patients who underwent surgery. Patients with a ganglion or a defined cause of compression should be operated, patients who present without a distinct reason for compression should firstly be treated conservatively. Physiotherapy, antiphlogistic medication and avoiding of the pain triggering motion can improve the symptoms. However, if muscle atrophy is evident

  1. Anatomic variations of superficial peroneal nerve: clinical implications of a cadaver study.

    PubMed

    Prakash; Bhardwaj, Ajay Kumar; Singh, Deepak Kumar; Rajini, T; Jayanthi, V; Singh, Gajendra

    2010-01-01

    Superficial peroneal nerve and its branches are frequently at risk for iatrogenic damage. Although different studies on anatomical variations of superficial peroneal nerve are available in the medical literature, such reports are rare from India. Hence the present study was undertaken on Indian population. A total of 60 specimens of inferior extremities from 30 properly embalmed and formalin fixed cadavers were dissected and examined for the location and course of the superficial peroneal nerve including number, level, course and distributions of branches. The superficial peroneal nerve in 28.3% specimens was located in the anterior compartment of the leg. In 8.3% specimens the superficial peroneal nerve branched before piercing between the peroneus longus and extensor digitorum longus muscle whereas in 11.7% specimens it branched after piercing the aforementioned muscles and before piercing the deep fascia. In 41 out of 60 specimens the sensory division of superficial peroneal nerve branched into the medial dorsal cutaneous nerve and intermediate dorsal cutaneous nerve distal to its emergence from the deep fascia and proximal to its relation to the extensor retinaculum. In 20 out of 60 specimens the accessory deep peroneal nerve, an additional branch from the sensory division of superficial peroneal nerve, through its course in the anterior compartment of the leg passed deep to the extensor retinaculum and supplied the ankle and the dorsum of foot. Hopefully the present study will help in minimizing iatrogenic damage to the superficial peroneal nerve and its branches while performing arthroscopy, local anesthetic block, surgical approach to the fibula, open reduction and internal fixation of lateral malleolar fractures, application of external fixators, elevation of a fasciocutaneous or fibular flaps for grafting, surgical decompression of neurovascular structures, or miscellaneous surgery on leg, foot and ankle.

  2. Peripheral nerve hyperexcitability syndromes.

    PubMed

    Küçükali, Cem Ismail; Kürtüncü, Murat; Akçay, Halil İbrahim; Tüzün, Erdem; Öge, Ali Emre

    2015-01-01

    Peripheral nerve hyperexcitability (PNH) syndromes can be subclassified as primary and secondary. The main primary PNH syndromes are neuromyotonia, cramp-fasciculation syndrome (CFS), and Morvan's syndrome, which cause widespread symptoms and signs without the association of an evident peripheral nerve disease. Their major symptoms are muscle twitching and stiffness, which differ only in severity between neuromyotonia and CFS. Cramps, pseudomyotonia, hyperhidrosis, and some other autonomic abnormalities, as well as mild positive sensory phenomena, can be seen in several patients. Symptoms reflecting the involvement of the central nervous system occur in Morvan's syndrome. Secondary PNH syndromes are generally seen in patients with focal or diffuse diseases affecting the peripheral nervous system. The PNH-related symptoms and signs are generally found incidentally during clinical or electrodiagnostic examinations. The electrophysiological findings that are very useful in the diagnosis of PNH are myokymic and neuromyotonic discharges in needle electromyography along with some additional indicators of increased nerve fiber excitability. Based on clinicopathological and etiological associations, PNH syndromes can also be classified as immune mediated, genetic, and those caused by other miscellaneous factors. There has been an increasing awareness on the role of voltage-gated potassium channel complex autoimmunity in primary PNH pathogenesis. Then again, a long list of toxic compounds and genetic factors has also been implicated in development of PNH. The management of primary PNH syndromes comprises symptomatic treatment with anticonvulsant drugs, immune modulation if necessary, and treatment of possible associated dysimmune and/or malignant conditions. PMID:25719304

  3. Optic nerve hypoplasia

    PubMed Central

    Kaur, Savleen; Jain, Sparshi; Sodhi, Harsimrat B. S.; Rastogi, Anju; Kamlesh

    2013-01-01

    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

  4. Large, central acellular zones indicating myoepithelial tumor differentiation in high-grade invasive ductal carcinomas as markers of predisposition to lung and brain metastases.

    PubMed

    Tsuda, H; Takarabe, T; Hasegawa, F; Fukutomi, T; Hirohashi, S

    2000-02-01

    High-grade invasive ductal carcinomas (IDCs) of the breast with large, central acellular zones on their cut surfaces are usually associated with the myoepithelial immunophenotype of carcinoma cells, which includes the expression of S-100 protein, alpha-smooth muscle actin, and keratin 14. To clarify the clinical significance of these features of IDCs, the authors compared the incidence of the myoepithelial immunophenotype immunohistochemically, patient prognosis, and metastatic sites of the tumor between 20 high-grade IDCs with large, central acellular zones and 40 control high-grade IDCs without these zones. The myoepithelial immunophenotype was detected in 16 IDCs (80%) with large, central acellular zones but in only seven IDCs (18%) without. The risk ratio of metastasis, especially in the brain and lung, and death from cancer were significantly higher (p = 0.0096 and p = 0.030) for the 20 IDCs with large, central acellular zones than for those without by Cox's univariate analysis. Using Cox's multivariate analysis, large, central acellular zones in IDCs were an indicator of high risk of brain and lung metastases and of death by cancer independent of nodal status and tumor size. Examination of large, central acellular zones and myoepithelial immunophenotype in high-grade IDCs appears helpful in predicting patient prognosis and preferential metastatic sites of the tumors.

  5. 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

  6. 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...

  7. 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.

  8. 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

  9. [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

  10. [Electrical nerve stimulation for plexus and nerve blocks].

    PubMed

    Birnbaum, J; Klotz, E; Bogusch, G; Volk, T

    2007-11-01

    Despite the increasing use of ultrasound, electrical nerve stimulation is commonly used as the standard for both plexus and peripheral nerve blocks. Several recent randomized trials have contributed to a better understanding of physiological and clinical correlations. Traditionally used currents and impulse widths are better defined in relation to the distance between needle tip and nerves. Commercially available devices enable transcutaneous nerve stimulation and provide new opportunities for the detection of puncture sites and for training. The electrically ideal position of the needle usually is defined by motor responses which can not be interpreted without profound anatomical knowledge. For instance, interscalene blocks can be successful even after motor responses of deltoid or pectoral muscles. Infraclavicular blocks should be aimed at stimulation of the posterior fascicle (extension). In contrast to multiple single nerve blocks, axillary single-shot blocks more commonly result in incomplete anaesthesia. Blockade of the femoral nerve can be performed without any nerve stimulation if the fascia iliaca block is used. Independently of the various approaches to the sciatic nerve, inversion and plantar flexion are the best options for single-shot blocks. Further clinical trials are needed to define the advantages of stimulating catheters in continuous nerve blocks.

  11. Nerves and nerve endings in the skin of tropical cattle.

    PubMed

    Amakiri, S F; Ozoya, S E; Ogunnaike, P O

    1978-01-01

    The nerves and nerve endings in the skin of tropical cattle were studied using histological and histochemical techniques. Many nerve trunks and fibres were present in the reticular and papillary dermis in both hairy and non-hairy skin sites. In non-hairy skin locations such as the muzzle and lower lip, encapsulated endings akin to Krause and Ruffini end bulbs, which arise from myelinated nerve trunks situated lower down the dermis were observed at the upper papillary layer level. Some fibre trunks seen at this level extended upwards to terminate within dermal papillae as bulb-shaped longitudinally lamellated Pacinian-type endings, while other onion-shaped lamellated nerve structures were located either within dermal papillae or near the dermo-epidermal area. Intraepidermal free-ending nerve fibres, appearing non-myelinated were observed in areas with thick epidermis. Intraepidermal free-ending nerve fibres, appearing non-myelinated were observed in areas with thick epidermis. On hairy skin sites, however, organized nerve endings or intraepidermal nerve endings were not readily identifiable. PMID:76410

  12. 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.

  13. Nerve Cross-Bridging to Enhance Nerve Regeneration in a Rat Model of Delayed Nerve Repair

    PubMed Central

    2015-01-01

    There are currently no available options to promote nerve regeneration through chronically denervated distal nerve stumps. Here we used a rat model of delayed nerve repair asking of prior insertion of side-to-side cross-bridges between a donor tibial (TIB) nerve and a recipient denervated common peroneal (CP) nerve stump ameliorates poor nerve regeneration. First, numbers of retrogradely-labelled TIB neurons that grew axons into the nerve stump within three months, increased with the size of the perineurial windows opened in the TIB and CP nerves. Equal numbers of donor TIB axons regenerated into CP stumps either side of the cross-bridges, not being affected by target neurotrophic effects, or by removing the perineurium to insert 5-9 cross-bridges. Second, CP nerve stumps were coapted three months after inserting 0-9 cross-bridges and the number of 1) CP neurons that regenerated their axons within three months or 2) CP motor nerves that reinnervated the extensor digitorum longus (EDL) muscle within five months was determined by counting and motor unit number estimation (MUNE), respectively. We found that three but not more cross-bridges promoted the regeneration of axons and reinnervation of EDL muscle by all the CP motoneurons as compared to only 33% regenerating their axons when no cross-bridges were inserted. The same 3-fold increase in sensory nerve regeneration was found. In conclusion, side-to-side cross-bridges ameliorate poor regeneration after delayed nerve repair possibly by sustaining the growth-permissive state of denervated nerve stumps. Such autografts may be used in human repair surgery to improve outcomes after unavoidable delays. PMID:26016986

  14. Association of postpartum maternal tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine administration and timeliness of infant immunization.

    PubMed

    Kaur, Ishminder; George, Krissa J; Pena-Ricardo, Carolina; Kelly, Barbara A; Watson, Barbara

    2013-11-01

    A retrospective cohort study was conducted on infants of mothers delivering at an inner-city hospital in October 2009 where postpartum maternal tetanus toxoid, reduced diptheria toxoid and acellular pertussis (Tdap) vaccination had been initiated in May 2008. We compared mothers and infants in a Tdap intervention group discharged July 2008 (n=250) with a pre-Tdap control group discharged July 2007 (n=238). Postpartum maternal Tdap impacted positively timeliness of early infant immunization.

  15. 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

  16. 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.

  17. Polyphenol-Stabilized Tubular Elastin Scaffolds for Tissue Engineered Vascular Grafts

    PubMed Central

    Chuang, Ting-Hsien; Stabler, Christopher; Simionescu, Agneta

    2009-01-01

    Tissue-engineered vascular grafts require elastic, acellular porous scaffolds with controlled biodegradability and properties matching those of natural arteries. Elastin would be a desirable component for such applications, but elastin does not easily regenerate experimentally. Our approach is to develop tubular elastin scaffolds using decellularization and removal of collagen from porcine carotid arteries (∼5 mm diameter) using alkaline extraction. Because elastin is susceptible to rapid degeneration after implantation, scaffolds were further treated with penta-galloyl glucose (PGG), an established polyphenolic elastin-stabilizing agent. Scaffolds were compared in vitro with detergent-decellularized arteries for structure, composition, resistance to degradation, mechanical properties, and cytotoxicity and in vivo for cell infiltration and remodeling potential. Results showed effective decellularization and almost complete collagen removal by alkaline extraction. PGG-treated elastin scaffolds proved to be resistant to elastase digestion in vitro, maintained their cylindrical shapes, showed high resistance to burst pressures, and supported growth of endothelial cells and fibroblasts. In vivo results showed that PGG treatment reduced the rate of elastin biodegradation and controlled cell infiltration but did not hamper new collagen and proteoglycan deposition and secretion of matrix-degrading proteases. Alkali-purified, PGG-treated tubular arterial elastin scaffolds exhibit many desirable properties to be recommended for clinical applications as vascular grafts. PMID:19254115

  18. [Imaging anatomy of cranial nerves].

    PubMed

    Hermier, M; Leal, P R L; Salaris, S F; Froment, J-C; Sindou, M

    2009-04-01

    Knowledge of the anatomy of the cranial nerves is mandatory for optimal radiological exploration and interpretation of the images in normal and pathological conditions. CT is the method of choice for the study of the skull base and its foramina. MRI explores the cranial nerves and their vascular relationships precisely. Because of their small size, it is essential to obtain images with high spatial resolution. The MRI sequences optimize contrast between nerves and surrounding structures (cerebrospinal fluid, fat, bone structures and vessels). This chapter discusses the radiological anatomy of the cranial nerves.

  19. Use of peracetic acid to sterilize human donor skin for production of acellular dermal matrices for clinical use.

    PubMed

    Huang, Qizhi; Dawson, Rebecca A; Pegg, David E; Kearney, John N; Macneil, Sheila

    2004-01-01

    We previously reported methods for sterilizing human skin for clinical use. In a comparison of gamma-irradiation, glycerol, and ethylene oxide, sterilization with ethylene oxide after treatment with glycerol provided the most satisfactory dermis in terms of structure and its ability to produce reconstructed skin with many of the characteristics of normal skin. However, the use of ethylene oxide is becoming less common in the United Kingdom due to concerns about its possible genotoxicity. The aim of this study was to evaluate peracetic acid as an alternative sterilizing agent. Skin sterilized with peracetic acid was compared with skin sterilized using glycerol alone or glycerol with ethylene oxide. The effect of subsequently storing peracetic acid sterilized skin in glycerol or propylene glycol was also examined. Acellular dermal matrices were produced after removal of the epidermis and cells in the dermis, processed for histological and ultrastructural analysis, and the biological function was evaluated by reconstitution with keratinocytes and fibroblasts. Results showed that sterilized acellular matrices retained the integrity of dermal structure and major components of the basement membrane. There were no overall significant differences in the ability of these matrices to form reconstructed skin, but peracetic acid alone gave a lower histologic score than when combined with glycerol or propylene glycol. We conclude that peracetic acid sterilization followed by preservation in glycerol or propylene glycol offers a convenient alternative protocol for processing of human skin. It is suggested that this sterile acellular dermis may be suitable for clinical use.

  20. 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

  1. 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

  2. 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.

  3. Electrospun bio-composite P(LLA-CL)/collagen I/collagen III scaffolds for nerve tissue engineering.

    PubMed

    Kijeńska, Ewa; Prabhakaran, Molamma P; Swieszkowski, Wojciech; Kurzydlowski, Krzysztof J; Ramakrishna, Seeram

    2012-05-01

    One of the biggest challenges in peripheral nerve tissue engineering is to create an artificial nerve graft that could mimic the extracellular matrix (ECM) and assist in nerve regeneration. Bio-composite nanofibrous scaffolds made from synthetic and natural polymeric blends provide suitable substrate for tissue engineering and it can be used as nerve guides eliminating the need of autologous nerve grafts. Nanotopography or orientation of the fibers within the scaffolds greatly influences the nerve cell morphology and outgrowth, and the alignment of the fibers ensures better contact guidance of the cells. In this study, poly (L-lactic acid)-co-poly(ε-caprolactone) or P(LLA-CL), collagen I and collagen III are utilized for the fabrication of nanofibers of different compositions and orientations (random and aligned) by electrospinning. The morphology, mechanical, physical, and chemical properties of the electrospun scaffolds along with their biocompatibility using C17.2 nerve stem cells are studied to identify the suitable material compositions and topography of the electrospun scaffolds required for peripheral nerve regeneration. Aligned P(LLA-CL)/collagen I/collagen III nanofibrous scaffolds with average diameter of 253 ± 102 nm were fabricated and characterized with a tensile strength of 11.59 ± 1.68 MPa. Cell proliferation studies showed 22% increase in cell proliferation on aligned P(LLA-CL)/collagen I/collagen III scaffolds compared with aligned pure P(LLA-CL) scaffolds. Results of our in vitro cell proliferation, cell-scaffold interaction, and neurofilament protein expression studies demonstrated that the electrospun aligned P(LLA-CL)/collagen I/collagen III nanofibrous scaffolds mimic more closely towards the ECM of nerve and have great potential as a substrate for accelerated regeneration of the nerve.

  4. 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

  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. 3D multi-channel bi-functionalized silk electrospun conduits for peripheral nerve regeneration.

    PubMed

    Dinis, T M; Elia, R; Vidal, G; Dermigny, Q; Denoeud, C; Kaplan, D L; Egles, C; Marin, F

    2015-01-01

    Despite technological advances over the past 25 years, a complete recovery from peripheral nerve injuries remains unsatisfactory today. The autograft is still considered the "gold standard" in clinical practice; however, postoperative complications and limited availability of nerve tissue have motivated the development of alternative approaches. Among them, the development of biomimetic nerve graft substitutes is one of the most promising strategies. In this study, multichanneled silk electrospun conduits bi-functionalized with Nerve Growth Factor (NGF) and Ciliary Neurotropic Factor (CNTF) were fabricated to enhance peripheral nerve regeneration. These bioactive guides consisting of longitudinally oriented channels and aligned nanofibers were designed in order to mimic the fascicular architecture and fibrous extracellular matrix found in native nerve. The simple use of the electrospinning technique followed by a manual manipulation to manufacture these conduits provides tailoring of channel number and diameter size to create perineurium-like structures. Functionalization of the silk fibroin nanofiber did not affect its secondary structure and chemical property. ELISA assays showed the absence of growth factors passive release from the functionalized fibers avoiding the topical accumulation of proteins. In addition, our biomimetic multichanneled functionalized nerve guides displayed a mechanical behavior comparable to that of rat sciatic nerve with an ultimate peak stress of 4.0 ± 0.6 MPa and a corresponding elongation at failure of 156.8 ± 46.7%. Taken together, our results demonstrate for the first time our ability to design and characterize a bi-functionalized nerve conduit consisting of electrospun nanofibers with multichannel oriented and nanofibers aligned for peripheral regeneration. Our bioactive silk tubes thus represent a new and promising technique towards the creation of a biocompatible nerve guidance conduit. PMID:25460402

  7. 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

  8. 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

  9. 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

  10. Are Aortic Stent Grafts Safe in Pregnancy?

    PubMed Central

    Khandanpour, Nader; Mehta, Tapan A.; Adiseshiah, M.; Meyer, Felicity J.

    2015-01-01

    Aortic stent grafts are increasingly used to treat aortic aneurysms and also other aortic pathologies. The safety of aortic stent grafts in pregnancy has never been studied or reported. We report on two cases of aortic stent grafts in pregnant women and discuss the effect of pregnancy on these aortic stent grafts. PMID:26229702

  11. 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.

  12. Nerve regeneration restores supraspinal control of bladder function after complete spinal cord injury.

    PubMed

    Lee, Yu-Shang; Lin, Ching-Yi; Jiang, Hai-Hong; Depaul, Marc; Lin, Vernon W; Silver, Jerry

    2013-06-26

    A life-threatening disability after complete spinal cord injury is urinary dysfunction, which is attributable to lack of regeneration of supraspinal pathways that control the bladder. Although numerous strategies have been proposed that can promote the regrowth of severed axons in the adult CNS, at present, the approaches by which this can be accomplished after complete cord transection are quite limited. In the present study, we modified a classic peripheral nerve grafting technique with the use of chondroitinase to facilitate the regeneration of axons across and beyond an extensive thoracic spinal cord transection lesion in adult rats. The novel combination treatment allows for remarkably lengthy regeneration of certain subtypes of brainstem and propriospinal axons across the injury site and is followed by markedly improved urinary function. Our studies provide evidence that an enhanced nerve grafting strategy represents a potential regenerative treatment after severe spinal cord injury.

  13. Nerve Regeneration Restores Supraspinal Control of Bladder Function after Complete Spinal Cord Injury

    PubMed Central

    Lin, Ching-Yi; Jiang, Hai-Hong; DePaul, Marc; Lin, Vernon W.

    2013-01-01

    A life-threatening disability after complete spinal cord injury is urinary dysfunction, which is attributable to lack of regeneration of supraspinal pathways that control the bladder. Although numerous strategies have been proposed that can promote the regrowth of severed axons in the adult CNS, at present, the approaches by which this can be accomplished after complete cord transection are quite limited. In the present study, we modified a classic peripheral nerve grafting technique with the use of chondroitinase to facilitate the regeneration of axons across and beyond an extensive thoracic spinal cord transection lesion in adult rats. The novel combination treatment allows for remarkably lengthy regeneration of certain subtypes of brainstem and propriospinal axons across the injury site and is followed by markedly improved urinary function. Our studies provide evidence that an enhanced nerve grafting strategy represents a potential regenerative treatment after severe spinal cord injury. PMID:23804083

  14. Growth interaction between locus coeruleus and trigeminal ganglion after intraocular double grafting.

    PubMed

    Seiger, A

    1980-06-01

    Fetal trigeminal ganglia were combined in the anterior chamber of eyes of rat recipients with sequentially grafted fetal locus coeruleus transplants. After maturation of both grafts in oculo the growth pattern of locus coeruleus derived noradrenaline fibres in the iris was examined with Falck-Hillarp fluorescence histochemistry. Contrary to what was expected from earlier studies, which revealed a radiating halo of fibres around the CNS tissue on the iris, the locus coeruleus-derived fibres radiated to a large extent from the adjacent trigeminal ganglion attachment. Thus, the presence of a grafted trigeminal ganglion changed the distribution of the central monoamine nerves growing out in the iris. The possible cause of this changed distribution is discussed. Maturated intraocular trigeminal ganglion transplants were retransplanted, together with the whole iris to which it was attached, into a new eye which already harboured a maturated locus coeruleus graft attached to its host iris. The expected reinitiated locus coeruleus fibre ingrowths into the iris transplants were then compared in those iris transplants that had trigeminal ganglia and controls that had not. The surface area of the iris grafts covered by newly formed locus coeruleus noradrenaline fibres was significantly smaller (27% reduction) if trigeminal ganglia were situated on them during the reinnervation process. This finding strongly supports our earlier studies, which suggested that the presence of sensory nerves in the iris inhibits growth of locus coeruleus in that receptor tissue, and furthermore, that the sensory nerves responsible for this inhibitory interaction have their origin within the trigeminal ganglion itself. PMID:7253725

  15. Functions of the Renal Nerves.

    ERIC Educational Resources Information Center

    Koepke, John P.; DiBona, Gerald F.

    1985-01-01

    Discusses renal neuroanatomy, renal vasculature, renal tubules, renin secretion, renorenal reflexes, and hypertension as related to renal nerve functions. Indicates that high intensitites of renal nerve stimulation have produced alterations in several renal functions. (A chart with various stimulations and resultant renal functions and 10-item,…

  16. Sports and peripheral nerve injury.

    PubMed

    Hirasawa, Y; Sakakida, K

    1983-01-01

    Peripheral nerve injury is one of the serious complications of athletic injuries; however, they have rarely been reported. According to the report by Takazawa et al., there were only 28 cases of peripheral nerve injury among 9,550 cases of sports injuries which had been treated in the previous 5 years at the clinic of the Japanese Athletic Association. The authors have encountered 1,167 cases of peripheral nerve injury during the past 18 years. Sixty-six of these cases were related to sports (5.7%). The nerves most frequently involved were: brachial plexus, radial nerve, ulnar, peroneal, and axillary nerves (in their order of frequency). The most common causes of such injuries were mountain climbing, gymnastics, and baseball. More often, peripheral nerve injury seemed to be caused by continuous compression and repeated trauma to the involved nerve. Usually it appeared as an entrapment neuropathy and the symptoms could be improved by conservative treatment. Some of the cases were complicated by fractures and surgical exploration became necessary. Results of treatment produced excellent to good improvement in 87.9% of the cases. With regard to compartment syndrome, the authors stress the importance of early and precise diagnosis and a fasciotomy.

  17. 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. ...

  18. Ultrasonographic Evaluation of Peripheral Nerves.

    PubMed

    Ali, Zarina S; Pisapia, Jared M; Ma, Tracy S; Zager, Eric L; Heuer, Gregory G; Khoury, Viviane

    2016-01-01

    There are a variety of imaging modalities for evaluation of peripheral nerves. Of these, ultrasonography (US) is often underused. There are several advantages of this imaging modality, including its cost-effectiveness, time-efficient assessment of long segments of peripheral nerves, ability to perform dynamic maneuvers, lack of contraindications, portability, and noninvasiveness. It can provide diagnostic information that cannot be obtained by electrophysiologic or, in some cases, magnetic resonance imaging studies. Ideally, the neurosurgeon can use US as a diagnostic adjunct in the preoperative assessment of a patient with traumatic, neoplastic, infective, or compressive nerve injury. Perhaps its most unique use is in intraoperative surgical planning. In this article, a brief description of normal US nerve anatomy is presented followed by a description of the US appearance of peripheral nerve disease caused by trauma, tumor, infection, and entrapment.

  19. Teeth and tooth nerves.

    PubMed

    Hildebrand, C; Fried, K; Tuisku, F; Johansson, C S

    1995-02-01

    (1) Although our knowledge on teeth and tooth nerves has increased substantially during the past 25 years, several important issues remain to be fully elucidated. As a result of the work now going on at many laboratories over the world, we can expect exciting new findings and major break-throughs in these and other areas in a near future. (2) Dentin-like and enamel-like hard tissues evolved as components of the exoskeletal bony armor of early vertebrates, 500 million years ago, long before the first appearance of teeth. It is possible that teeth developed from tubercles (odontodes) in the bony armor. The presence of a canal system in the bony plates, of tubular dentin, of external pores in the enamel layer and of a link to the lateral line system promoted hypotheses that the bony plates and tooth precursors may have had a sensory function. The evolution of an efficient brain, of a head with paired sense organs and of toothed jaws concurred with a shift from a sessile filter-feeding life to active prey hunting. (3) The wide spectrum of feeding behaviors exhibited by modern vertebrates is reflected by a variety of dentition types. While the teeth are continuously renewed in toothed non-mammalian vertebrates, tooth turnover is highly restricted in mammals. As a rule, one set of primary teeth is replaced by one set of permanent teeth. Since teeth are richly innervated, the turnover necessitates a local neural plasticity. Another factor calling for a local plasticity is the relatively frequent occurrence of age-related and pathological dental changes. (4) Tooth development is initiated through interactions between the oral epithelium and underlying neural crest-derived mesenchymal cells. The interactions are mediated by cell surface molecules, extracellular matrix molecules and soluble molecules. The possibility that the initiating events might involve a neural component has been much discussed. With respect to mammals, the experimental evidence available does not

  20. 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

  1. 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

  2. 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

  3. Acellular dermal matrix slings in tissue expander breast reconstruction: are there substantial benefits?

    PubMed

    Collis, George N; TerKonda, Sarvam P; Waldorf, James C; Perdikis, Galen

    2012-05-01

    Acellular dermal matrix (ADM) slings in breast reconstruction are increasingly used but are not yet validated. This study compares immediate, expander-based breast reconstruction with and without the use of inferolateral ADM slings. There were 63 patients (106 breasts) in the ADM group and 42 patients (68 breasts) in the control group. Initial intraoperative fill volumes were significantly greater in the ADM group, median 69% full (250 mL) versus 50% full (180 mL; P < 0.001). However, the number of days to complete expansion between the 2 groups was similar. One less office visit was required to complete the fills in the ADM group (P < 0.01). Drains were removed 3 days later in the ADM group (P < 0.01). Overall complication rate was greater in the ADM group (18.9% vs. 7.4%, P < 0.05), with a slightly higher percentage of expanders requiring removal due to infection in the ADM group (5.7% vs. 4.4%, P = NS). This study suggests inferolateral ADM slings in expander-based breast reconstruction allow for significantly increased initial fill volumes and may offer an aesthetic advantage; however, its use is costly and increases complications.

  4. Changing from whole-cell to acellular pertussis vaccines would trade superior tolerability for inferior protection.

    PubMed

    Herzog, Christian

    2015-01-01

    Notifications of infant deaths, assumed to be related to the introduction of new pentavalent DTwP-Hib-HBV childhood vaccines, caused, during 2008-2010 in few Asian countries, temporary interruptions of the respective vaccination programs. The sudden appearance of fatal cases was due to increased awareness/publicity and improved safety monitoring/reporting in countries with relatively high background infant mortalities. WHO investigations could not establish any causal relationships and vaccinations were again resumed. Recently, questions were raised in one concerned country as to why not to change to less reactogenic acellular pertussis (aP)-containing vaccines that are available in private practice and are generally perceived as 'better'. For resource-poor countries, the financial impacts render such a switch impossible and would also not be supported by external funding. Furthermore, it would be a disservice to the children, as in recent years evidence of inferior long-term efficacy of aP vaccines has accumulated. This report summarizes current knowledge on comparative whole-cell pertussis (wP) and aP vaccine performance, outlines the new July 2014 WHO guidance on the choice of pertussis vaccines and presents recent data on outbreak protection, antibody waning, long-term protection, wP-priming, pathogen adaptation, transmission and herd immunity.

  5. 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.

  6. 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

  7. Nanopatterned acellular valve conduits drive the commitment of blood-derived multipotent cells

    PubMed Central

    Di Liddo, Rosa; Aguiari, Paola; Barbon, Silvia; Bertalot, Thomas; Mandoli, Amit; Tasso, Alessia; Schrenk, Sandra; Iop, Laura; Gandaglia, Alessandro; Parnigotto, Pier Paolo; Conconi, Maria Teresa; Gerosa, Gino

    2016-01-01

    Considerable progress has been made in recent years toward elucidating the correlation among nanoscale topography, mechanical properties, and biological behavior of cardiac valve substitutes. Porcine TriCol scaffolds are promising valve tissue engineering matrices with demonstrated self-repopulation potentiality. In order to define an in vitro model for investigating the influence of extracellular matrix signaling on the growth pattern of colonizing blood-derived cells, we cultured circulating multipotent cells (CMC) on acellular aortic (AVL) and pulmonary (PVL) valve conduits prepared with TriCol method and under no-flow condition. Isolated by our group from Vietnamese pigs before heart valve prosthetic implantation, porcine CMC revealed high proliferative abilities, three-lineage differentiative potential, and distinct hematopoietic/endothelial and mesenchymal properties. Their interaction with valve extracellular matrix nanostructures boosted differential messenger RNA expression pattern and morphologic features on AVL compared to PVL, while promoting on both matrices the commitment to valvular and endothelial cell-like phenotypes. Based on their origin from peripheral blood, porcine CMC are hypothesized in vivo to exert a pivotal role to homeostatically replenish valve cells and contribute to hetero- or allograft colonization. Furthermore, due to their high responsivity to extracellular matrix nanostructure signaling, porcine CMC could be useful for a preliminary evaluation of heart valve prosthetic functionality. PMID:27789941

  8. Production of an acellular matrix from amniotic membrane for the synthesis of a human skin equivalent.

    PubMed

    Sanluis-Verdes, Anahí; Yebra-Pimentel Vilar, Maria Teresa; García-Barreiro, Juan Javier; García-Camba, Marta; Ibáñez, Jacinto Sánchez; Doménech, Nieves; Rendal-Vázquez, Maria Esther

    2015-09-01

    Human amniotic membrane (HAM) has useful properties as a dermal matrix substitute. The objective of our work was to obtain, using different enzymatic or chemical treatments to eliminate cells, a scaffold of acellular HAM for later use as a support for the development of a skin equivalent. The HAM was separated from the chorion, incubated and cryopreserved. The membrane underwent different enzymatic and chemical treatments to eliminate the cells. Fibroblasts and keratinocytes were separately obtained from skin biopsies of patients following a sequential double digestion with first collagenase and then trypsin-EDTA (T/E). A skin equivalent was then constructed by seeding keratinocytes on the epithelial side and fibroblasts on the chorionic side of the decellularizated HAM. Histological, immunohistochemical, inmunofluorescent and molecular biology studies were performed. Treatment with 1% T/E at 37 °C for 30 min totally removed epithelial and mesenchymal cells. The HAM thus treated proved to be a good matrix to support adherence of cells and allowed the achievement of an integral and intact scaffold for development of a skin equivalent, which could be useful as a skin substitute for clinical use.

  9. A new candidate substrate for cell-matrix adhesion study: the acellular human amniotic matrix.

    PubMed

    Guo, Qianchen; Lu, Xuya; Xue, Yuan; Zheng, Hong; Zhao, Xiaotao; Zhao, Huajian

    2012-01-01

    In vivo adhesions between cells and the extracellular matrix play a crucial role in cell differentiation, proliferation, and migration as well as tissue remodeling. Natural three-dimensional (3D) matrices, such as self-assembling matrices and Matrigel, have limitations in terms of their biomechanical properties. Here, we present a simple method to produce an acellular human amniotic matrix (AHAM) with preserved biomechanical properties and a favorable adhesion potential. On the stromal side of the AHAM, human foreskin fibroblasts (HFFs) attached and extended with bipolar spindle-shaped morphology proliferated to multilayer networks, invaded into the AHAM, and migrated in a straight line. Moreover, αV integrin, paxillin, and fibronectin were observed to colocalize after 24 h of HFF culture on the stromal side of the AHAM. Our results indicate that the AHAM may be an ideal candidate as a cell-matrix adhesion substrate to study cell adhesion and invasion as well as other functions in vitro under a tensile force that mimics the in vivo environment.

  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.

  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. PMID:27190645

  12. Does tetanus-diphtheria-acellular pertussis vaccination interfere with serodiagnosis of pertussis infection?

    PubMed

    Pawloski, Lucia C; Kirkland, Kathryn B; Baughman, Andrew L; Martin, Monte D; Talbot, Elizabeth A; Messonnier, Nancy E; Tondella, Maria Lucia

    2012-06-01

    An anti-pertussis toxin (PT) IgG enzyme-linked immunosorbent assay (ELISA) was analytically validated for the diagnosis of pertussis at a cutoff of 94 ELISA units (EU)/ml. Little was known about the performance of this ELISA in the diagnosis of adults recently vaccinated with tetanus-diphtheria-acellular pertussis (Tdap) vaccine, which contains PT. The goal of this study was to determine when the assay can be used following Tdap vaccination. A cohort of 102 asymptomatic health care personnel (HCP) vaccinated with Tdap (Adacel; Sanofi Pasteur) were aged 19 to 79 years (median, 47 years) at vaccination. For each HCP, specimens were available for evaluation at 2 to 10 time points (prevaccination to 24 months postvaccination), and geometric mean concentrations (GMC) for the cohort were calculated at each time point. Among 97 HCP who responded to vaccination, a mixed-model analysis with prediction and tolerance intervals was performed to estimate the time at which serodiagnosis can be used following vaccination. The GMCs were 8, 21, and 9 EU/ml at prevaccination and 4 and 12 months postvaccination, respectively. Eight (8%) of the 102 HCP reached antibody titers of ≥94 EU/ml during their peak response, but none had these titers by 6 months postvaccination. The calculated prediction and tolerance intervals were <94 EU/ml by 45 and 75 days postvaccination, respectively. Tdap vaccination 6 months prior to testing did not confound result interpretation. This seroassay remains a valuable diagnostic tool for adult pertussis.

  13. 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.

  14. 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

  15. Glottic Regeneration with Tissue Engineering Technique Using Acellular Extracellular Matrix Scaffold in Canine Model

    PubMed Central

    Kitamura, Morimasa; Hirano, Shigeru; Kanemaru, Shin-ichi; Kitani, Yoshiharu; Ohno, Satoshi; Kojima, Tsuyoshi; Nakamura, Tatsuo; Ito, Juichi; Rosen, Clark A.; Gilbert, Thomas W.

    2014-01-01

    Acellular extracellular matrix scaffold derived from porcine urinary bladder (UBM) is decellularized material that has shown success for constructive remodeling of various tissues and organs. The regenerative effects of UBM were reported for the tympanic membrane, esophagus, trachea, larynx, pleura, and pericardium in animal studies with promising results. The aim of this study was to investigate regenerative effects of UBM to regenerate hemilarynx using a canine model. A left partial hemilaryngectomy was performed, and the surgical defects were reconstructed by insertion of UBM scaffold. Although local infection was observed in one dog in a week after implantation of the scaffold, all dogs showed good re-epithelialization with minimum complication in one month. The effect of regeneration of the larynx was evaluated 6 months after the operation. The excised larynx experiments were performed to measure phonation threshold pressure (PTP), normalized mucosal wave amplitude (NMWA), and normalized glottal gap (NGG). The results of the measurements showed that PTP was normal or near normal in 2 cases, NMWA was within normal range in 3 cases, although there were individual variations. Histologic examination was completed to evaluate structural changes of the scaffold with appearance of new cartilaginous structure. However the regenerated vocal fold mucosa is mostly scarred. The UBM scaffold has shown to be biocompatible, biodegradable, and useful for tissue regeneration of the hemilarynx with possible restoration of the vocal fold function. The vocal fold mucosa was scarred, which is the next challenge to improve. PMID:24403099

  16. Acellular Dermal Allograft for Sellar Repair after Transsphenoidal Approach to Pituitary Adenomas

    PubMed Central

    Gaynor, Brandon G.; Benveniste, Ronald J.; Lieberman, Seth; Casiano, Roy; Morcos, Jacques J.

    2013-01-01

    Objectives Our practice has transitioned from using fat autograft to acellular dermal matrix (AlloDerm, LifeCell Corp, Woodlands, Texas, USA). We present the largest series to our knowledge of AlloDerm for sellar floor repair after transsphenoidal approach to pituitary adenoma and compare rates of postoperative cerebrospinal fluid (CSF) leak with an earlier cohort of patients whose CSF leaks were repaired with fat autograft. Design This is a retrospective cohort study comparing sellar repair with fat autograft versus inlay Alloderm between the years 2003 and 2012. The primary end point was postoperative CSF leak. Results A total of 429 patients (368 primary; 83 revision operations) without intraoperative lumbar drainage were included. A total of 18 postoperative CSF leaks were observed (3.9%). Intraoperative CSF leak occurred in 160 cases (35.5%). Among this subset of patients with intraoperative CSF leak, 95 underwent repair with AlloDerm and 46 underwent repair with fat autograft, with postoperative CSF leak rates of 8.4% and 15.2%, respectively (p = 0.34, chi-square test); 19 patients underwent repair with other techniques or no repair at all, with postoperative leak rate of 0%. Conclusions AlloDerm is an effective alternative to fat autograft in cases of low-flow CSF leak following transsphenoidal resection of pituitary adenoma. PMID:24436906

  17. Xenogeneic acellular dermal matrix in combination with pectoralis major myocutaneous flap reconstructs hypopharynx and cervical esophagus.

    PubMed

    Yin, Danhui; Tang, Qinglai; Wang, Shuang; Li, Shisheng; He, Xiangbo; Liu, Jiajia; Liu, Bingbing; Yang, Mi; Yang, Xinming

    2015-11-01

    The aim of this study was to explore xenogeneic acellular dermal matrix (ADM) in combination with pectoralis major myocutaneous flap in hypopharynx and cervical esophagus reconstruction. A total of five patients were treated with this surgical method to reconstruct hypopharynx and cervical esophagus in Second Xiangya Hospital between January 2012 and April 2013. Four of them had hypopharyngeal carcinoma with laryngeal and cervical esophageal invasion, while the fifth patient with hypopharyngeal cancer had developed scars and atresia after postoperative radiotherapy. The defect length after hypopharyngeal and cervical esophageal resection was 6-8 cm, and was repaired by a combination of ADM and pectoralis major myocutaneous flap by our team. Interestingly, the four patients had primary healing and regained their eating function about 2-3 weeks after surgery, the fifth individual suffered from pharyngeal fistula, but recovered after dressing change about 2 months. Postoperative esophageal barium meals revealed that the pharynx and esophagus were unobstructed in all five patients. Xenogeneic ADM in combination with pectoralis major myocutaneous flap for hypopharynx and cervical esophagus reconstruction is a simple, safe and effective method with fewer complications. Nevertheless, according to the defect length of the cervical esophagus, the patients need to strictly follow the medical advice.

  18. Closure of the abdominal wall with acellular dermal allograft in intestinal transplantation.

    PubMed

    Mangus, R S; Kubal, C A; Tector, A J; Fridell, J A; Klingler, K; Vianna, R M

    2012-12-01

    Loss of abdominal domain is a common problem in intestinal transplantation. Several surgical options are available perioperatively for abdominal wall reconstruction. This study reports the management and complications for intestinal transplant patients with abdominal wall closure either primarily or with foreign material. This single center study reviews the records of intestinal transplant patients between 2004 and 2010. Study outcomes included reoperation for dehiscence, hernia or enterocutaneous fistula. There were 37 of 146 patients (25%) who required implantation of foreign material at transplant. Of these 37, 30 (81%) had implantation of acellular dermal allograft (ADA) and 7 (19%) implantation of another mesh. Perioperative dehiscence was rare with 2/109 (2%) for primary closure, 0/30 (0%) for ADA and 1/7 (14%) for other mesh. There were 12/146 (8%) patients who underwent ventral hernia repair: primary closure 7/109 (6%), ADA 3/30 (10%) and other mesh 2/7 (28%). There were 4/146 (3%) patients who required surgery for enterocutaneous fistulas: 2/109 (2%) primary closure, 1/30 (3%) ADA and 1/7 (14%) synthetic mesh. Abdominal wall reconstruction with ADA biologic mesh provides an expeditious means of performing a tension-free closure of the fascial layer after intestinal transplantation with complications similar to those seen for primary closure.

  19. Nonallograft osteoconductive bone graft substitutes.

    PubMed

    Bucholz, Robert W

    2002-02-01

    An estimated 500,000 to 600,000 bone grafting procedures are done annually in the United States. Approximately (1/2) of these surgeries involve spinal arthrodesis whereas 35% to 40% are used for general orthopaedic applications. Synthetic bone graft substitutes currently represent only 10% of the bone graft market, but their share is increasing as experience and confidence in their use are accrued. Despite 15 to 20 years of clinical experience with various synthetic substitutes, there have been few welldesigned, controlled clinical trials of these implants. Synthetic bone graft substitutes consist of hydroxyapatite, tricalcium phosphate, calcium sulfate, or a combination of these minerals. Their fabrication technique, crystallinity, pore dimensions, mechanical properties, and resorption rate vary. All synthetic porous substitutes share numerous advantages over autografts and allografts including their unlimited supply, easy sterilization, and storage. However, the degree to which the substitute provides an osteoconductive structural framework or matrix for new bone ingrowth differs among implants. Disadvantages of ceramic implants include brittle handling properties, variable rates of resorption, poor performance in diaphyseal defects, and potentially adverse effects on normal bone remodeling. These inherent weaknesses have refocused their primary use to bone graft extenders and carriers for pharmaceuticals. The composition, histologic features, indications, and clinical experience of several of the synthetic bone graft substitutes approved for orthopaedic use in the United States are reviewed. PMID:11937865

  20. 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

  1. 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

  2. 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

  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 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

  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

    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.

  5. Peripheral nerve blocks for distal extremity surgery.

    PubMed

    Offierski, Chris

    2013-10-01

    Peripheral nerve block is well suited for distal extremity surgery. Blocking the nerves at the distal extremity is easily done. It does not require ultrasound or stimulators to identify the nerve. Blocking nerves in the distal extremity is safe with low risk of toxicity. The effect of the nerve block is limited to the distribution of the nerve. The distal nerves in the lower extremity are sensory branches of the sciatic nerve. This provides a sensory block only. This has the advantage of allowing the patient to actively contract tendons in the foot and ambulate more quickly after surgery. PMID:24093651

  6. 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

  7. The effects of acellular amniotic membrane matrix on osteogenic differentiation and ERK1/2 signaling in human dental apical papilla cells.

    PubMed

    Chen, Yi-Jane; Chung, Min-Chun; Jane Yao, Chung-Chen; Huang, Chien-Hsun; Chang, Hao-Hueng; Jeng, Jiiang-Huei; Young, Tai-Horng

    2012-01-01

    The amniotic membrane (AM) has been widely used in the field of tissue engineering because of the favorable biological properties for scaffolding material. However, little is known about the effects of an acellular AM matrix on the osteogenic differentiation of mesenchymal stem cells. In this study, it was found that both basement membrane side and collagenous stroma side of the acellular AM matrix were capable of providing a preferential environment for driving the osteogenic differentiation of human dental apical papilla cells (APCs) with proven stem cell characteristics. Acellular AM matrix potentiated the induction effect of osteogenic supplements (OS) such as ascorbic acid, β-glycerophosphate, and dexamethasone and enhanced the osteogenic differentiation of APCs, as seen by increased core-binding factor alpha 1 (Cbfa-1) phosphorylation, alkaline phosphatase activity, mRNA expression of osteogenic marker genes, and mineralized matrix deposition. Even in the absence of soluble OS, acellular AM matrix also could exert the substrate-induced effect on initiating APCs' differentiation. Especially, the collagenous stroma side was more effective than the basement membrane side. Moreover, the AM-induced effect was significantly inhibited by U0126, an inhibitor of extracellular signaling-regulated kinase 1/2 (ERK1/2) signaling. Taken together, the osteogenic differentiation promoting effect on APCs is AM-specific, which provides potential applications of acellular AM matrix in bone/tooth tissue engineering.

  8. 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

  9. "High-grade" central acellular carcinoma and matrix-producing carcinoma of the breast: correlation between ultrasonographic findings and pathological features.

    PubMed

    Yamaguchi, Rin; Tanaka, Maki; Mizushima, Yasuko; Hirai, Yoshitake; Yamaguchi, Miki; Terasaki, Hiroshi; Yokoyama, Toshiro; Tsuchiya, Shin-ichi; Nakashima, Osamu; Yano, Hirohisa

    2011-09-01

    High-grade carcinoma with a large central acellular zone (central acellular carcinoma, CAC) and matrixproducing carcinoma (MPC) are aggressive tumors that both have a central myxomatous acellular zone. Their characteristic morphology may be useful in diagnostic imaging. Ultrasonographic findings based on the Breast Imaging Recording and Data System (BI-RADS) and detailed histological features were evaluated in 11 cases of CAC and 2 cases of MPC to characterize their features. Safranin-O staining was undertaken for the evaluation of central acellular zones in these tumors. Overall, ultrasonography demonstrated heterogeneous hyperechoic lesions in the center of the hypoechoic mass. Posterior echo enhancement was observed in all but 1 case. One case was classified as malignant and the others as "borderline." Histologically, cancer tissue was located in the periphery of the tumor with a ring-like structure and fewer cellular central areas comprising hyaline cartilage myxoid material such as those stained by safranin-O. The present study showed that the pathological findings of CACs and MPCs accurately reflect the ultrasonographic findings. Tumors that showed hyperechoic areas in the center of the hypoechoic mass, with posterior echo enhancement indicating acellular zones composed by myxochondroid material, and that were also relatively round on ultrasonography may be benign, but evaluation is required to exclude CAC and MPC.

  10. 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

  11. 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

  12. A porcine-derived acellular dermal scaffold that supports soft tissue regeneration: removal of terminal galactose-alpha-(1,3)-galactose and retention of matrix structure.

    PubMed

    Xu, Hui; Wan, Hua; Zuo, Wenqi; Sun, Wendell; Owens, Rick T; Harper, John R; Ayares, David L; McQuillan, David J

    2009-07-01

    Sub-optimal clinical outcomes after implantation of animal-derived tissue matrices may be attributed to the nature of the processing of the material or to an immune response elicited in response to xenogeneic epitopes. The ability to produce a porcine-derived graft that retains the structural integrity of the extracellular matrix and minimizes potential antigenic response to galactose-alpha-(1,3)-galactose terminal disaccharide (alpha-Gal) may allow the scaffold to support regeneration of native tissue. Dermal tissue from wild-type (WT-porcine-derived acellular dermal matrix [PADM]) or Gal-deficient (Gal(-/-) PADM) pigs was processed to remove cells and DNA while preserving the structural integrity of the extracellular matrix. In addition, the WT tissue was subjected to an enzymatic treatment to minimize the presence of alpha-Gal (Gal-reduced PADM). Extracellular matrix composition and integrity was assessed by histological, immunohistochemical (IHC), and ultrastructural analysis. In vivo performance was evaluated by implantation into the abdominal wall of Old World primates in an exisional repair model. Anti-alpha-Gal activity in the serum of monkeys implanted subcutaneously was assessed by ELISA. Minimal modification to the extracellular matrix was assessed by evaluation of intact structure as demonstrated by staining patterns for type I and type VII collagens, laminin, and fibronectin similar to native porcine skin tissues. Explants from the abdominal wall showed evidence of remodeling, notably fibroblast cell repopulation and revascularization, as early as 1 month. Serum ELISA revealed an initial anti-alpha-Gal induction that decreased to baseline levels over time in the primates implanted with WT-PADM, whereas no or minimal anti-Gal activity was detected in the primates implanted with Gal(-/-) PADM or Gal-reduced PADM. The combination of a nondamaging process, successful removal of cells, and reduction of xenogeneic alpha-Gal antigens from the porcine dermal

  13. 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

  14. Recent advances in nerve tissue engineering.

    PubMed

    Zhang, Bill G X; Quigley, Anita F; Myers, Damian E; Wallace, Gordon G; Kapsa, Robert M I; Choong, Peter F M

    2014-04-01

    Nerve injury secondary to trauma, neurological disease or tumor excision presents a challenge for surgical reconstruction. Current practice for nerve repair involves autologous nerve transplantation, which is associated with significant donor-site morbidity and other complications. Previously artificial nerve conduits made from polycaprolactone, polyglycolic acid and collagen were approved by the FDA (USA) for nerve repair. More recently, there have been significant advances in nerve conduit design that better address the requirements of nerve regrowth. Innovations in materials science, nanotechnology, and biology open the way for the synthesis of new generation nerve repair conduits that address issues currently faced in nerve repair and regeneration. This review discusses recent innovations in this area, including the use of nanotechnology to improve the design of nerve conduits and to enhance nerve regeneration.

  15. Thyroid hormone dependency in immature but not mature grafted locus coeruleus neurons. Evidence from intraocular innervation of iris transplants.

    PubMed

    Granholm, A C; Seiger, A

    1981-02-01

    Fetal brain tissue pieces containing locus coeruleus noradrenaline neurons were combined with sequentially or simultaneously grafted irides in the anterior eye chamber of thyroidectomized or normal host rats. The aim was to reveal possible morphological alterations in the adrenergic fibres innervating the iris grafts, induced by thyroid hormone deficiency, and to compare that possible hormone dependency with what has been found before in host irides innervated by locus coeruleus neurons. Nerve fibre outgrowth was evaluated in iris whole mounts, using Falck Hillarp fluorescence histochemistry. The distribution of locus-coeruleus-derived fibres on host irides was markedly altered in the thyroidectomized hosts. The number of fluorescent axon bundles was significantly decreased, and the intermingled varicose nerve fibre plexus contained numerous accumulations of fluorescent material. In the iris grafts from normal or thyroidectomized hosts reinnervated by matyured locus coeruleus neurons there was no difference in distribution or morphology between the two groups. This clearly shows that matured locus coeruleus neurons are not thyroid hormone dependent during a reinnervation process, after the stimulus elicited by a sensory denervation of iris. When immature locus coeruleus neurons were made to innervate iris grafts by simultaneous grafting of brain tissue and an iris to the eye a clearly reduced number of axon bundles was formed in the iris grafts of the thyroidectomized group. The morphological discrepancies between the two groups were, however, markedly smaller for iris grafts than for corresponding host irides. This might indicate that the potent growth stimulus elicited by sensory denervation of irides partly counteract the inhibition of axon bundle formation by immature grafted locus coeruleus neurons in irides during thyroid hormone deficiency. PMID:7266087

  16. 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

  17. Bone graft substitute: allograft and xenograft.

    PubMed

    Shibuya, Naohiro; Jupiter, Daniel C

    2015-01-01

    Rapid bone graft incorporation for structural rigidity is essential. Early range of motion, exercise, and weight-bearing are keys to rehabilitation. Structural and nonstructural bone grafts add length, height, and volume to alter alignment, function, and appearance. Bone graft types include: corticocancellous autograft, allograft, xenograft, and synthetic graft. Autogenic grafts are harvested from the patient, less likely to be rejected, and more likely to be incorporated; however, harvesting adds a procedure and donor site complication is common. Allografts, xenografts, and synthetic grafts eliminate secondary procedures and donor site complications; however, rejection and slower incorporation can occur.

  18. Craniofacial Bone Grafting: Wolff's Law Revisited

    PubMed Central

    Oppenheimer, Adam J.; Tong, Lawrence; Buchman, Steven R.

    2008-01-01

    Bone grafts are used for the reconstruction of congenital and acquired deformities of the facial skeleton and, as such, comprise a vital component of the craniofacial surgeon's armamentarium. A thorough understanding of bone graft physiology and the factors that affect graft behavior is therefore essential in developing a more intelligent use of bone grafts in clinical practice. This article presents a review of the basic physiology of bone grafting along with a survey of pertinent concepts and current research. The factors responsible for bone graft survival are emphasized. PMID:22110789

  19. 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

  20. Acellular Dermal Matrix as a Core Strut for Projection in Nipple Reconstruction: Approaches for Three Different Methods of Breast Reconstruction

    PubMed Central

    Park, Gui-Yong; Cho, Hee-Eun; Lee, Byung-Il; Park, Seung-Ha

    2016-01-01

    Background The objective of this paper was to describe a novel technique for improving the maintenance of nipple projection in primary nipple reconstruction by using acellular dermal matrix as a strut in one of three different configurations, according to the method of prior breast reconstruction. The struts were designed to best fill the different types of dead spaces in nipple reconstruction depending on the breast reconstruction method. Methods A total of 50 primary nipple reconstructions were performed between May 2012 and May 2015. The prior breast reconstruction methods were latissimus dorsi (LD) flap (28 cases), transverse rectus abdominis myocutaneous (TRAM) flap (10 cases), or tissue expander/implant (12 cases). The nipple reconstruction technique involved the use of local flaps, including the C-V flap or star flap. A 1×2-cm acellular dermal matrix was placed into the core with O-, I-, and L-shaped struts for prior LD, TRAM, and expander/implant methods, respectively. The projection of the reconstructed nipple was measured at the time of surgery and at 3, 6, and 9 months postoperatively. Results The nine-month average maintenance of nipple projection was 73.0%±9.67% for the LD flap group using an O-strut, 72.0%±11.53% for the TRAM flap group using an I-strut, and 69.0%±10.82% for the tissue expander/implant group using an L-strut. There were no cases of infection, wound dehiscence, or flap necrosis. Conclusions The application of an acellular dermal matrix with a different kind of strut for each of 3 breast reconstruction methods is an effective addition to current techniques for improving the maintenance of long-term projection in primary nipple reconstruction. PMID:27689049

  1. Structural and redox behavior of OxyVita, a zero-linked polymeric hemoglobin: comparison with natural acellular polymeric hemoglobins.

    PubMed

    Harrington, John P; Orlik, Kseniya; Orlig, Kseniya; Zito, Samantha L; Wollocko, Jacek; Wollocko, Hanna

    2010-04-01

    A zero-linked polymeric hemoglobin (OxyVita Hb) has been developed for application as an acellular therapeutic hemoglobin-based-oxygen-carrier (HBOC). For effective and safe oxygen binding, transport and delivery, an HBOC must meet essential molecular requirements related to its structural integrity and redox stability. OxyVita is a super polymer possessing an average M.wt. of 17 x 10(6) Da. Structural integrity was determined by unfolding studies of OxyVita in the presence of increasing concentrations of urea. The unfolding midpoints (D(1/2)) of different preparations of OxyVita (solution and powder forms) were compared to Lumbricus Hb (LtHb) and Arenicola Hb (ArHb), natural acellular polymeric hemoglobins, which are serving as models for an effective and safe acellular HBOC. Reduction studies of OxyVita Hb using endogenous reducing agents were also investigated. Results from these studies indicate that: 1) OxyVita Hb exhibits greater resistance to conformational change than either LtHb or ArHb in the reduced (oxyHb) state; and 2) the reduction of met OxyVita Hb to oxyHb occurs slowly in the presence of either ascorbic acid (70% reduction in 560 min.) or beta-NADH (40% reduction in 90 min.). These studies provide consistent evidence that OxyVita Hb possesses physiochemical properties that exhibit structural integrity and redox behavior necessary for functioning as an effective and safe HBOC within clinical applications. These results are in agreement with observations made by other investigators as to the reduction in heme-loss of OxyVita Hb, essential for the reversible binding/release of molecular oxygen within the circulatory system. PMID:20196683

  2. Structural and redox behavior of OxyVita, a zero-linked polymeric hemoglobin: comparison with natural acellular polymeric hemoglobins.

    PubMed

    Harrington, John P; Orlik, Kseniya; Orlig, Kseniya; Zito, Samantha L; Wollocko, Jacek; Wollocko, Hanna

    2010-04-01

    A zero-linked polymeric hemoglobin (OxyVita Hb) has been developed for application as an acellular therapeutic hemoglobin-based-oxygen-carrier (HBOC). For effective and safe oxygen binding, transport and delivery, an HBOC must meet essential molecular requirements related to its structural integrity and redox stability. OxyVita is a super polymer possessing an average M.wt. of 17 x 10(6) Da. Structural integrity was determined by unfolding studies of OxyVita in the presence of increasing concentrations of urea. The unfolding midpoints (D(1/2)) of different preparations of OxyVita (solution and powder forms) were compared to Lumbricus Hb (LtHb) and Arenicola Hb (ArHb), natural acellular polymeric hemoglobins, which are serving as models for an effective and safe acellular HBOC. Reduction studies of OxyVita Hb using endogenous reducing agents were also investigated. Results from these studies indicate that: 1) OxyVita Hb exhibits greater resistance to conformational change than either LtHb or ArHb in the reduced (oxyHb) state; and 2) the reduction of met OxyVita Hb to oxyHb occurs slowly in the presence of either ascorbic acid (70% reduction in 560 min.) or beta-NADH (40% reduction in 90 min.). These studies provide consistent evidence that OxyVita Hb possesses physiochemical properties that exhibit structural integrity and redox behavior necessary for functioning as an effective and safe HBOC within clinical applications. These results are in agreement with observations made by other investigators as to the reduction in heme-loss of OxyVita Hb, essential for the reversible binding/release of molecular oxygen within the circulatory system.

  3. Acellular Dermal Matrix as a Core Strut for Projection in Nipple Reconstruction: Approaches for Three Different Methods of Breast Reconstruction

    PubMed Central

    Park, Gui-Yong; Cho, Hee-Eun; Lee, Byung-Il; Park, Seung-Ha

    2016-01-01

    Background The objective of this paper was to describe a novel technique for improving the maintenance of nipple projection in primary nipple reconstruction by using acellular dermal matrix as a strut in one of three different configurations, according to the method of prior breast reconstruction. The struts were designed to best fill the different types of dead spaces in nipple reconstruction depending on the breast reconstruction method. Methods A total of 50 primary nipple reconstructions were performed between May 2012 and May 2015. The prior breast reconstruction methods were latissimus dorsi (LD) flap (28 cases), transverse rectus abdominis myocutaneous (TRAM) flap (10 cases), or tissue expander/implant (12 cases). The nipple reconstruction technique involved the use of local flaps, including the C-V flap or star flap. A 1×2-cm acellular dermal matrix was placed into the core with O-, I-, and L-shaped struts for prior LD, TRAM, and expander/implant methods, respectively. The projection of the reconstructed nipple was measured at the time of surgery and at 3, 6, and 9 months postoperatively. Results The nine-month average maintenance of nipple projection was 73.0%±9.67% for the LD flap group using an O-strut, 72.0%±11.53% for the TRAM flap group using an I-strut, and 69.0%±10.82% for the tissue expander/implant group using an L-strut. There were no cases of infection, wound dehiscence, or flap necrosis. Conclusions The application of an acellular dermal matrix with a different kind of strut for each of 3 breast reconstruction methods is an effective addition to current techniques for improving the maintenance of long-term projection in primary nipple reconstruction.

  4. Solitary fibrous tumour of the vagus nerve.

    PubMed

    Scholsem, Martin; Scholtes, Felix

    2012-04-01

    We describe the complete removal of a foramen magnum solitary fibrous tumour in a 36-year-old woman. It originated on a caudal vagus nerve rootlet, classically described as the 'cranial' accessory nerve root. This ninth case of immunohistologically confirmed cranial or spinal nerve SFT is the first of the vagus nerve.

  5. Management of traumatic facial nerve injuries.

    PubMed

    Greywoode, Jewel D; Ho, Hao H; Artz, Gregory J; Heffelfinger, Ryan N

    2010-12-01

    Management of facial nerve injuries requires knowledge and skills that should be in every facial plastic surgeon's armamentarium. This article will briefly review the anatomy of the facial nerve, discuss the assessment of facial nerve injury, and describe the management of facial nerve injury after soft tissue trauma. PMID:21086238

  6. 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

  7. [Nerve-sparing radical prostatectomy].

    PubMed

    Okada, K; Tada, M; Nakano, A; Konno, T

    1988-04-01

    The neuroanatomy of the pelvic space was studied in order to clarify the course of cavernous nerves responsible for erectile function. The cavernous nerves travel along the dorsolateral portion at the base toward the apex of the prostate, then penetrate urogenital diaphragm at the lateral aspect of the membranous urethra. According to the anatomical findings, nerve-sparing radical prostatectomy was performed through the antegrade approach in 28 patients with prostate cancer. No significant surgical complications were encountered in the present series. Of the 28, evaluable cases were limited to 22 in terms of erection. Fifteen patients (68%) recovered their erectile function after nerve-sparing surgery. Therefore, the present surgical technique seems to be effective for the preservation of male sexual function following radical pelvic surgery.

  8. Schwannomatosis of Cervical Vagus Nerve

    PubMed Central

    Sasi, M. P.

    2016-01-01

    Cervical vagal schwannoma is a rare entity among lesions presenting as a neck mass. They are usually slow-growing benign lesions closely associated with the vagus nerve. They are usually solitary and asymptomatic. Multiple schwannomas occurring in patients without neurofibromatosis (NF) are rare and have recently been referred to as schwannomatosis. Here, we present a case of a neck mass that had imaging features suggestive of vagal schwannoma and was operated upon. Intraoperatively, it was discovered to be a case of multiple vagal cervical schwannoma, all directly related to the right vagus nerve, and could be resected from the nerve in toto preserving the function of the vagus nerve. Final HPR confirmed our pre-op suspicion of vagal schwannomatosis.

  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. 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.

  11. 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

  12. 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

  13. 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

  14. 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

  15. Randomized controlled trial of minimally invasive surgery using acellular dermal matrix for complex anorectal fistula

    PubMed Central

    A ba-bai-ke-re, Ma-Mu-Ti-Jiang; Wen, Hao; Huang, Hong-Guo; Chu, Hui; Lu, Ming; Chang, Zhong-Sheng; Ai, Er-Ha-Ti; Fan, Kai

    2010-01-01

    AIM: To compare the efficacy and safety of acellular dermal matrix (ADM) bioprosthetic material and endorectal advancement flap (ERAF) in treatment of complex anorectal fistula. METHODS: Ninety consecutive patients with complex anorectal fistulae admitted to Anorectal Surgical Department of First Affiliated Hospital, Xinjiang Medical University from March 2008 to July 2009, were enrolled in this study. Complex anorectal fistula was diagnosed following its clinical, radiographic, or endoscopic diagnostic criteria. Under spinal anesthesia, patients underwent identification and irrigation of the fistula tracts using hydrogen peroxide. ADM was securely sutured at the secondary opening to the primary opening using absorbable suture. Outcomes of ADM and ERAF closure were compared in terms of success rate, fecal incontinence rate, anorectal deformity rate, postoperative pain time, closure time and life quality score. Success was defined as closure of all external openings, absence of drainage without further intervention, and absence of abscess formation. Follow-up examination was performed 2 d, 2, 4, 6, 12 wk, and 5 mo after surgery, respectively. RESULTS: No patient was lost to follow-up. The overall success rate was 82.22% (37/45) 5.7 mo after surgery. ADM dislodgement occured in 5 patients (11.11%), abscess formation was found in 1 patient, and fistula recurred in 2 patients. Of the 13 patients with recurrent fistula using ERAF, 5 (11.11%) received surgical drainage because of abscess formation. The success rate, postoperative pain time and closure time of ADM were significantly higher than those of ERAF (P < 0.05). However, no difference was observed in fecal incontinence rate and anorectal deformity rate after treatment with ADM and ERAF. CONCLUSION: Closure of fistula tract opening with ADM is an effective procedure for complex anorectal fistula. ADM should be considered a first line treatment for patients with complex anorectal fistula. PMID:20614483

  16. 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

  17. 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.

  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. 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

  20. 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

  1. Different T cell memory in preadolescents after whole-cell or acellular pertussis vaccination.

    PubMed

    Smits, Kaatje; Pottier, Gaelle; Smet, Julie; Dirix, Violette; Vermeulen, Françoise; De Schutter, Iris; Carollo, Maria; Locht, Camille; Ausiello, Clara Maria; Mascart, Françoise

    2013-12-17

    To better understand vaccine-induced protection and its potential failure in light of recent whooping cough resurgence, we evaluated quantity as well as quality of memory T cell responses in B. pertussis-vaccinated preadolescent children. Using a technique based on flow cytometry to detect proliferation, cytokine production and phenotype of antigen-specific cells, we evaluated residual T cell memory in a cohort of preadolescents who received a whole-cell pertussis (wP; n=11) or an acellular pertussis vaccine (aP; n=13) during infancy, and with a median of 4 years elapsed from the last pertussis booster vaccine, which was aP for all children. We demonstrated that B. pertussis-specific memory T cells are detectable in the majority of preadolescent children several years after vaccination. CD4(+) and CD8(+) T cell proliferation in response to pertussis toxin and/or filamentous hemagglutinin was detected in 79% and 60% of the children respectively, and interferon-γ or tumor necrosis factor-α producing CD4(+) T cells were detected in 65% and 53% of the children respectively. Phenotyping of the responding cells showed that the majority of antigen-specific cells, whether defined by proliferation or cytokine production, were CD45RA(-)CCR7(-) effector memory T cells. Although the time since the last booster vaccine was significantly longer for wP-compared to aP-vaccinated children, their proliferation capacity in response to antigenic stimulation was comparable, and more children had a detectable cytokine response after wP- compared to aP-vaccination. This study supports at the immunological level recent epidemiological studies indicating that infant vaccination with wP induces longer lasting immunity than vaccination with aP-vaccines. PMID:24176499

  2. 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.

  3. 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

  4. 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. PMID:27622099

  5. 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

  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. Optic Nerve Monitoring

    PubMed Central

    Schumann, Paul; Kokemüller, Horst; Tavassol, Frank; Lindhorst, Daniel; Lemound, Juliana; Essig, Harald; Rücker, Martin; Gellrich, Nils-Claudius

    2013-01-01

    Orbital and anterior skull base surgery is generally performed close to the prechiasmatic visual pathway, and clear strategies for detecting and handling visual pathway damage are essential. To overcome the common problem of a missed clinical examination because of an uncooperative or unresponsive patient, flash visual evoked potentials and electroretinograms should be used. These electrophysiologic examination techniques can provide evidence of intact, pathologic, or absent conductivity of the visual pathway when clinical assessment is not feasible. Visual evoked potentials and electroretinograms are thus essential diagnostic procedures not only for primary diagnosis but also for intraoperative evaluation. A decision for or against treatment of a visual pathway injury has to be made as fast as possible due to the enormous importance of the time elapsed with such injuries; this can be achieved additionally using multislice spiral computed tomography. The first-line conservative treatment of choice for such injuries is megadose methylprednisolone therapy. Surgery is used to decompress the orbital compartment by exposure of the intracanalicular part of the optic nerve in the case of optic canal compression. Modern craniomaxillofacial surgery requires detailed consideration of the diagnosis and treatment of traumatic visual pathway damage with the ultimate goal of preserving visual acuity. PMID:24436741

  8. Mechanisms of trigeminal nerve injuries.

    PubMed

    Ziccardi, V B; Assael, L A

    2001-09-01

    Injuries to the trigeminal nerve branches are a known and accepted risk in oral and maxillofacial surgery. It is prudent for the practitioner to explain the risks to patients as part of the informed consent process and to recognize and document the presence of nerve injury postoperatively. Patients should be referred to a surgeon experienced in microsurgical techniques in a timely fashion for evaluation and possible surgical intervention if an injury is not resolving.

  9. Attempts to restore abduction of the paralyzed equine arytenoid cartilage. I. Nerve-muscle pedicle transplants.

    PubMed Central

    Ducharme, N G; Horney, F D; Partlow, G D; Hulland, T J

    1989-01-01

    The purpose of this project was to adapt a surgical technique from humans and dogs to horses in which a portion of an accessory muscle of respiration and its nerve supply is transplanted to a denervated dorsal cricoarytenoid muscle. Anatomical dissections in seven horses revealed two possible donor nerve-pedicle grafts: the omohyoid and the sternothyrohyoid, both innervated by a branch of the first and second cervical nerves. Histochemical evaluations in two ponies of the dorsal cricoarytenoid, omohyoid and sternothyrohyoid muscles revealed similar proportions of fiber types 1 and 2 in all three muscles. Electromyographic studies in these two ponies revealed that the omohyoid and sternothyrohyoid muscles contract synchronously with respirations during forced inspiration under general anesthesia. Based on surgical ease of access, a 1 cm2 portion of the omohyoid muscle at the point of penetration of the second cervical nerve was used as a nerve-muscle pedicle graft in an attempt to reinnervate the left dorsal cricoarytenoid muscle in four ponies. These four ponies (as well as three others which served as controls) had previously undergone left recurrent laryngeal nerve transection. All seven ponies endoscopically showed signs of complete left laryngeal hemiplegia immediately postoperatively. Animals were monitored endoscopically for 30 weeks after surgery. The three control ponies showed no abduction of the arytenoid cartilage. In addition, in these three ponies, histological and histochemical expected changes of muscle fiber atrophy and fibrosis were present in the dorsal cricoarytenoid muscle.(ABSTRACT TRUNCATED AT 250 WORDS) Images Fig. 1. Fig. 4. Fig. 5. Fig. 6. Fig. 7. Fig. 8. PMID:2713785

  10. [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

  11. Noninvasive imaging of peripheral nerves.

    PubMed

    Rangavajla, Gautam; Mokarram, Nassir; Masoodzadehgan, Nazanin; Pai, S Balakrishna; Bellamkonda, Ravi V

    2014-01-01

    Recent developments in the field of peripheral nerve imaging extend the capabilities of imaging modalities to assist in the diagnosis and treatment of patients with peripheral nerve maladies. Methods such as magnetic resonance imaging (MRI) and its derivative diffusion tensor imaging (DTI), ultrasound (US) and positron emission tomography (PET) are capable of assessing nerve structure and function following injury and relating the state of the nerve to electrophysiological and histological analysis. Of the imaging methods surveyed here, each offered unique and interesting advantages related to the field. MRI offered the opportunity to visualize immune activity on the injured nerve throughout the course of the regeneration process, and DTI offered numerical characterization of the injury and the ability to develop statistical bases for diagnosing injury. US extends imaging to the treatment phase by enabling more precise analgesic applications following surgery, and PET represents a novel method of assessing nerve injury through analysis of relative metabolism rates in injured and healthy tissue. Exciting new possibilities to enhance and extend the abilities of imaging methods are also discussed, including innovative contrast agents, some of which enable multimodal imaging approaches and present opportunities for treatment application. PMID:25766202

  12. Costal Cartilage Grafts in Rhinoplasty.

    PubMed

    Fedok, Fred G

    2016-01-01

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

  13. [Rehabilitation of facial paralysis using autogenous fascia lata graft. Stable results over time].

    PubMed

    Graillon, N; Colson, T; Bardot, J

    2015-10-01

    Dynamic facial reanimation with free muscle or nerve transfers represents the mainstay of facial paralysis treatments particularly for perioral area and smile. These techniques are not always feasible, in such cases we perform a perioral suspension with fascia lata graft. However many teams blame this technique for short-term recurrence of the deformity. We describe in this paper details of our surgical technique, to improve the aesthetic result and stability over time, and the results and complications encountered. Fascia lata graft was sutured beyond the midline to the contralateral healthy lips, after tunneling through upper and lower orbicularis oris. Fascia lata graft was then tunneled through the buccal fat pad, then under the zygomatic arch to the temporal region, where the temporal aponeurosis was incised to make way for the fascia lata graft, which was fixed to the outer face of the temporal aponeurosis, applying slight overcorrection to the oral commissure. From 2003 to 2012, we performed this procedure on 8 patients. Results showed an immediate aesthetic improvement, stable over time. Perioral suspension with fascia lata graft is a surgical alternative when dynamic reanimation is not feasible.

  14. Recanalization of an Occluded Infrainguinal Vein Graft Complicated by Graft Aneurysm

    SciTech Connect

    Kakani, Nirmal; Travis, Simon; Hancock, John

    2007-11-15

    The technique of subintimal angioplasty has been described for the recanalisation of native vessels after occlusion of infrainguinal vascular bypass grafts. We report a case in which an attempt at such treatment resulted in inadvertent but successful recanalisation of the occluded vein graft instead. This was complicated by graft perforation and subsequent graft aneurysm which was successfully treated with a covered stent.

  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.

  16. Nerve Regeneration in Rat Limb Allografts: Evaluation of Acute Rejection Rescue

    PubMed Central

    Yan, Ying; MacEwan, Matthew R.; Hunter, Daniel A.; Farber, Scott; Newton, Piyaraj; Tung, Thomas H.; Mackinnon, Susan E.; Johnson, Philip J.

    2013-01-01

    Background Successful nerve regeneration is critical to the functional success of composite tissue allografts (CTA). The present study was designed to characterize the effect of acute rejection on nerve regeneration and functional recovery in the setting of orthotopic limb transplantation. Methods A rat orthotopic limb transplantation model was used to evaluate the effects of acute rejection on nerve regeneration and motor recovery. Continuous administration of FK506 (Full suppression), administration of FK506 for the first 8 of 12 weeks (Late rejection), or delayed administration of FK506 / dexamethasone following noticeable rejection (Early rejection) was used to preclude or induce rejection following limb transplantation. Twelve weeks postoperatively, nerve regeneration was assessed via histomorphometric analysis of explanted sciatic nerve, and motor recovery was assessed via evoked muscle force measurement in extensor digitorum longus (EDL) muscle. Results A single episode of acute rejection that occurs immediately or late after reconstruction does not significantly alter the number of regenerating axonal fibers. Acute rejection occurring late after reconstruction adversely affects EDL muscle function in CTA. Conclusion Collected data reinforces that adequate immunosuppressant administration in cases of allogeneic limb transplantation ensures levels of nerve regeneration and motor functional recovery equivalent to that of syngeneic transplants. Prompt rescue following acute rejection was further demonstrated not to significantly affect nerve regeneration and functional recovery post-operatively. However, instances of acute rejection that occur late after reconstruction affect graft function. In total, the present study begins to characterize the effect of immunosuppression regimens on nerve regeneration and motor recovery in the setting of CTA. PMID:23542267

  17. Identification of adequate vehicles to carry nerve regeneration inducers using tubulisation

    PubMed Central

    2012-01-01

    Background Axonal regeneration depends on many factors, such as the type of injury and repair, age, distance from the cell body and distance of the denervated muscle, loss of surrounding tissue and the type of injured nerve. Experimental models use tubulisation with a silicone tube to research regenerative factors and substances to induce regeneration. Agarose, collagen and DMEM (Dulbecco’s modified Eagle’s medium) can be used as vehicles. In this study, we compared the ability of these vehicles to induce rat sciatic nerve regeneration with the intent of finding the least active or inert substance. The experiment used 47 female Wistar rats, which were divided into four experimental groups (agarose 4%, agarose 0.4%, collagen, DMEM) and one normal control group. The right sciatic nerve was exposed, and an incision was made that created a 10 mm gap between the distal and proximal stumps. A silicone tube was grafted onto each stump, and the tubes were filled with the respective media. After 70 days, the sciatic nerve was removed. We evaluated the formation of a regeneration cable, nerve fibre growth, and the functional viability of the regenerated fibres. Results Comparison among the three vehicles showed that 0.4% agarose gels had almost no effect on provoking the regeneration of peripheral nerves and that 4% agarose gels completely prevented fibre growth. The others substances were associated with profuse nerve fibre growth. Conclusions In the appropriate concentration, agarose gel may be an important vehicle for testing factors that induce regeneration without interfering with nerve growth. PMID:22889258

  18. 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

  19. 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.

  20. New variant for whole pancreas grafting

    SciTech Connect

    Kootstra, G.; van Hooff, J.P.; Joerning, P.J.L.; Leunissen, K.M.; van der Linden, C.J.; Beukers, E.; Buurman, W.A.

    1987-02-01

    A new variant for whole pancreas grafting is described in which a segment of the duodenum and the spleen is included in the graft. The graft is placed extraperitoneally as in kidney transplantation. The exocrine drainage is with side-to-side anastomosis between duodenum and bladder. The spleen is irradiated to prevent the occurrence of GVHD, as is reported in splenic transplantation.

  1. 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.

  2. Mortality and morbidity from invasive bacterial infections during a clinical trial of acellular pertussis vaccines in Sweden.

    PubMed

    Storsaeter, J; Olin, P; Renemar, B; Lagergård, T; Norberg, R; Romanus, V; Tiru, M

    1988-09-01

    A double blind placebo-controlled efficacy trial of two acellular pertussis vaccines was conducted in 3801 6- to 11-month-old children. Four vaccinated children died during 7 to 9 months follow-up as a result of Haemophilus influenzae type b meningitis, heroin intoxication with concomitant pneumonia, suspected septicemia, and Neisseria meningitidis Group B septicemia. From the actual death rate in children belonging to the same birth cohort in Sweden that could have been eligible for the trial, one death was expected among vaccinated children. Several investigations were carried out to examine the possibility that the deaths could be causally related to the vaccination. The relative risk for hospitalization due to systemic or respiratory infections was 1.07 (95% confidence interval, 0.95 to 1.20) and 0.83 (95% confidence interval, 0.64 to 1.08) in the vaccine groups as compared with the placebo group. Subsets of the population were studied for signs of immunosuppression. There was no indication of immunoglobulin deficiency or any sign of clinically significant leukopenia or lymphocytosis in vaccine recipients. The results of this analysis provide no evidence for a causal relation between vaccination with the studied acellular pertussis vaccines and altered resistance to invasive disease caused by encapsulated bacteria. The hypothesis that the two variables are related, however, cannot be refuted from these data.

  3. Sustained release of VEGF from PLGA nanoparticles embedded thermo-sensitive hydrogel in full-thickness porcine bladder acellular matrix

    PubMed Central

    2011-01-01

    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. PMID:21711840

  4. 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

  5. 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

  6. 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

  7. 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.

  8. Successful endothelialization and remodeling of a cell-free small-diameter arterial graft in a large animal model.

    PubMed

    Koobatian, Maxwell T; Row, Sindhu; Smith, Randall J; Koenigsknecht, Carmon; Andreadis, Stelios T; Swartz, Daniel D

    2016-01-01

    The large number of coronary artery bypass procedures necessitates development of off-the-shelf vascular grafts that do not require cell or tissue harvest from patients. However, immediate thrombus formation after implantation due to the absence of a healthy endothelium is very likely. Here we present the successful development of an acellular tissue engineered vessel (A-TEV) based on small intestinal submucosa that was functionalized sequentially with heparin and VEGF. A-TEVs were implanted into the carotid artery of an ovine model demonstrating high patency rates and significant host cell infiltration as early as one week post-implantation. At one month, a confluent and functional endothelium was present and the vascular wall showed significant infiltration of host smooth muscle cells exhibiting vascular contractility in response to vaso-agonists. After three months, the endothelium aligned in the direction of flow and the medial layer comprised of circumferentially aligned smooth muscle cells. A-TEVs demonstrated high elastin and collagen content as well as impressive mechanical properties and vascular contractility comparable to native arteries. This is the first demonstration of successful endothelialization, remodeling, and development of vascular function of a cell-free vascular graft that was implanted in the arterial circulation of a pre-clinical animal model.

  9. 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

  10. Retinal and optic nerve diseases.

    PubMed

    Margalit, Eyal; Sadda, Srinivas R

    2003-11-01

    A variety of disease processes can affect the retina and/or the optic nerve, including vascular or ischemic disease, inflammatory or infectious disease, and degenerative disease. These disease processes may selectively damage certain parts of the retina or optic nerve, and the specific areas that are damaged may have implications for the design of potential therapeutic visual prosthetic devices. Outer retinal diseases include age-related macular degeneration, pathologic myopia, and retinitis pigmentosa. Although the retinal photoreceptors may be lost, the inner retina is relatively well-preserved in these diseases and may be a target for retinal prosthetic devices. Inner retinal diseases include retinal vascular diseases such as diabetic retinopathy, retinal venous occlusive disease, and retinopathy of prematurity. Other retinal diseases such as ocular infections (retinitis, endophthalmitis) may affect all retinal layers. Because the inner retinal cells, including the retinal ganglion cells, may be destroyed in these diseases (inner retinal or whole retinal), prosthetic devices that stimulate the inner retina may not be effective. Common optic nerve diseases include glaucoma, optic neuritis, and ischemic optic neuropathy. Because the ganglion cell nerve fibers themselves are damaged, visual prosthetics for these diseases will need to target more distal portions of the visual pathway, such as the visual cortex. Clearly, a sound understanding of retinal and optic nerve disease pathophysiology is critical for designing and choosing the optimal visual prosthetic device.

  11. Recellularizing of human acellular dermal matrices imaged by high-definition optical coherence tomography.

    PubMed

    Boone, Marc A L M; Draye, Jean Pierre; Verween, Gunther; Aiti, Annalisa; Pirnay, Jean-Paul; Verbeken, Gilbert; De Vos, Daniel; Rose, Thomas; Jennes, Serge; Jemec, Gregor B E; Del Marmol, Veronique

    2015-05-01

    High-definition optical coherence tomography (HD-OCT) permits real-time 3D imaging of the impact of selected agents on human skin allografts. The real-time 3D HD-OCT assessment of (i) the impact on morphological and cellular characteristics of the processing of human acellular dermal matrices (HADMs) and (ii) repopulation of HADMs in vitro by human fibroblasts and remodelling of the extracellular matrix by these cells. Four different skin decellularization methods, Dispase II/Triton X-100, Dispase II/SDS (sodium dodecyl sulphate), NaCl/Triton X-100 and NaCl/SDS, were analysed by HD-OCT. HD-OCT features of epidermal removal, dermo-epidermal junction (DEJ) integrity, cellularity and dermal architecture were correlated with reflectance confocal microscopy (RCM), histopathology and immunohistochemistry. Human adult dermal fibroblasts were in vitro seeded on the NaCl/Triton X-100 processed HADMs, cultured up to 19 days and evaluated by HD-OCT in comparison with MTT proliferation test and histology. Epidermis was effectively removed by all treatments. DEJ was best preserved after NaCl/Triton X-100 treatment. Dispase II/SDS treatment seemed to remove all cellular debris in comparison with NaCl/Triton X-100 but disturbed the DEJ severely. The dermal micro-architectural structure and vascular spaces of (sub)papillary dermis were best preserved with the NaCl/Triton X-100. The impact on the 3D structure and vascular holes was detrimental with Dispase II/SDS. Elastic fibre fragmentation was only observed after Dispase II incubation. HD-OCT showed that NaCl/Triton X-100 processed matrices permitted in vitro repopulation by human dermal fibroblasts (confirmed by MTT test and histology) and underwent remodelling upon increasing incubation time. Care must be taken in choosing the appropriate processing steps to maintain selected properties of the extracellular matrix in HADMs. Processing HADMs with NaCl/Triton X-100 permits in vitro the proliferation and remodelling activity of

  12. 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.

  13. 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.

  14. Five Roots Pattern of Median Nerve Formation.

    PubMed

    Natsis, Konstantinos; Paraskevas, George; Tzika, Maria

    2016-01-01

    An unusual combination of median nerve's variations has been encountered in a male cadaver during routine educational dissection. In particular, the median nerve was formed by five roots; three roots originated from the lateral cord of the brachial plexus joined individually the median nerve's medial root. The latter (fourth) root was united with the lateral (fifth) root of the median nerve forming the median nerve distally in the upper arm and not the axilla as usually. In addition, the median nerve was situated medial to the brachial artery. We review comprehensively the relevant variants, their embryologic development and their potential clinical applications. PMID:27131354

  15. 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

  16. 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

  17. 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

  18. 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.

  19. Embryonic anastomosis between hypoglossal nerves.

    PubMed

    Rodríguez-Vázquez, J F; Mérida-Velasco, J R; Verdugo-López, S; Sanz-Casado, J V; Jiménez-Collado, J

    2009-12-01

    This article presents two cases of anastomosis of hypoglossal nerves in the suprahyoid region in human embryos of CR length 10.75 and 17.5 mm. This variation was studied in two human specimens at this stage of development and compared with the normal arrangement of the hypoglossal nerves in embryos at the same stage. The anastomotic branches were of similar caliber to the main trunks. In both cases the anastomosis was located dorsal to the origin of the geniohyoid muscles and caudal to the genioglossus muscles, lying transversally over the cranial face of the body of the hyoid bone anlage. The anastomosis formed a suprahyoid nerve chiasm on the midline in the embryo of 10.75 mm CR length.

  20. Masseteric-facial nerve transposition for reanimation of the smile in incomplete facial paralysis.

    PubMed

    Hontanilla, Bernardo; Marre, Diego

    2015-12-01

    Incomplete facial paralysis occurs in about a third of patients with Bell's palsy. Although their faces are symmetrical at rest, when they smile they have varying degrees of disfigurement. Currently, cross-face nerve grafting is one of the most useful techniques for reanimation. Transfer of the masseteric nerve, although widely used for complete paralysis, has not to our knowledge been reported for incomplete palsy. Between December 2008 and November 2013, we reanimated the faces of 9 patients (2 men and 7 women) with incomplete unilateral facial paralysis with transposition of the masseteric nerve. Sex, age at operation, cause of paralysis, duration of denervation, recipient nerves used, and duration of follow-up were recorded. Commissural excursion, velocity, and patients' satisfaction were evaluated with the FACIAL CLIMA and a questionnaire, respectively. The mean (SD) age at operation was 39 (±6) years and the duration of denervation was 29 (±19) months. There were no complications that required further intervention. Duration of follow-up ranged from 6-26 months. FACIAL CLIMA showed improvement in both commissural excursion and velocity of more than two thirds in 6 patients, more than one half in 2 patients and less than one half in one. Qualitative evaluation showed a slight or pronounced improvement in 7/9 patients. The masseteric nerve is a reliable alternative for reanimation of the smile in patients with incomplete facial paralysis. Its main advantages include its consistent anatomy, a one-stage operation, and low morbidity at the donor site. PMID:26143295

  1. Development of biomaterial scaffold for nerve tissue engineering: Biomaterial mediated neural regeneration

    PubMed Central

    2009-01-01

    Neural tissue repair and regeneration strategies have received a great deal of attention because it directly affects the quality of the patient's life. There are many scientific challenges to regenerate nerve while using conventional autologous nerve grafts and from the newly developed therapeutic strategies for the reconstruction of damaged nerves. Recent advancements in nerve regeneration have involved the application of tissue engineering principles and this has evolved a new perspective to neural therapy. The success of neural tissue engineering is mainly based on the regulation of cell behavior and tissue progression through the development of a synthetic scaffold that is analogous to the natural extracellular matrix and can support three-dimensional cell cultures. As the natural extracellular matrix provides an ideal environment for topographical, electrical and chemical cues to the adhesion and proliferation of neural cells, there exists a need to develop a synthetic scaffold that would be biocompatible, immunologically inert, conducting, biodegradable, and infection-resistant biomaterial to support neurite outgrowth. This review outlines the rationale for effective neural tissue engineering through the use of suitable biomaterials and scaffolding techniques for fabrication of a construct that would allow the neurons to adhere, proliferate and eventually form nerves. PMID:19939265

  2. 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

  3. Masseteric-facial nerve transposition for reanimation of the smile in incomplete facial paralysis.

    PubMed

    Hontanilla, Bernardo; Marre, Diego

    2015-12-01

    Incomplete facial paralysis occurs in about a third of patients with Bell's palsy. Although their faces are symmetrical at rest, when they smile they have varying degrees of disfigurement. Currently, cross-face nerve grafting is one of the most useful techniques for reanimation. Transfer of the masseteric nerve, although widely used for complete paralysis, has not to our knowledge been reported for incomplete palsy. Between December 2008 and November 2013, we reanimated the faces of 9 patients (2 men and 7 women) with incomplete unilateral facial paralysis with transposition of the masseteric nerve. Sex, age at operation, cause of paralysis, duration of denervation, recipient nerves used, and duration of follow-up were recorded. Commissural excursion, velocity, and patients' satisfaction were evaluated with the FACIAL CLIMA and a questionnaire, respectively. The mean (SD) age at operation was 39 (±6) years and the duration of denervation was 29 (±19) months. There were no complications that required further intervention. Duration of follow-up ranged from 6-26 months. FACIAL CLIMA showed improvement in both commissural excursion and velocity of more than two thirds in 6 patients, more than one half in 2 patients and less than one half in one. Qualitative evaluation showed a slight or pronounced improvement in 7/9 patients. The masseteric nerve is a reliable alternative for reanimation of the smile in patients with incomplete facial paralysis. Its main advantages include its consistent anatomy, a one-stage operation, and low morbidity at the donor site.

  4. 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.

  5. Rehabilitation of peripheral nerve injuries.

    PubMed

    Robinson, Michael D; Shannon, Steven

    2002-02-01

    Traumatic injuries to peripheral nerves pose complex challenges to both military and civilian physicians. Treatment of nerve injuries must consider all aspects of the inherent disability. Pain control is of paramount importance. Little will be accomplished until pain is brought down to tolerable levels. Rehabilitation needs to be instituted as first-line treatment. Focus must be first placed on protection of the affected area from complications stemming from disuse and immobility and then on enhancement of strength, flexibility, sensory discrimination, and dexterity. Early intervention sets the stage for optimal physiologic and functional recovery. PMID:11878078

  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. 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

  8. Nonrecurrent Laryngeal Nerve in the Era of Intraoperative Nerve Monitoring

    PubMed Central

    Gurleyik, Gunay

    2016-01-01

    Nonrecurrent laryngeal nerve (non-RLN) is an anatomical variation increasing the risk of vocal cord palsy. Prediction and early identification of non-RLN may minimize such a risk of injury. This study assessed the effect of intraoperative neuromonitoring (IONM) on the detection of non-RLN. A total of 462 (236 right) nerves in 272 patients were identified and totally exposed, and all intraoperative steps of IONM were sequentially applied on the vagus nerve (VN) and RLN. Right predissection VN stimulation at a distal point did not create a sound signal in three cases (3/236; 1.27%). Proximal dissection of the right VN under IONM guidance established a proximal point, creating a positive signal. The separation point of non-RLN from VN was discovered in all three patients. Non-RLNs were exposed from separation to laryngeal entry. Positive IONM signals were obtained after resection of thyroid lobes, and postoperative period was uneventful in patients with non-RLN. Absence of distal VN signal is a precise predictor of the non-RLN. IONM-guided proximal dissection of the right VN leads to identification of the non-RLN. The prediction of non-RLN by the absence of the VN signal at an early stage of surgery may prevent or minimize the risk of nerve injury.

  9. 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.

  10. Cadaveric aorta implantation for aortic graft infection.

    PubMed

    Ali, Asad; Bahia, Sandeep S S; Ali, Tahir

    2016-01-01

    This case report describes a 73-year-old gentleman who underwent explantation of an infected prosthetic aorto-iliac graft and replacement with a cryopreserved thoracic and aorto-iliac allograft. The patient has been followed up a for more than a year after surgery and remains well. After elective tube graft repair of his abdominal aortic aneurysm (AAA) in 2003, he presented to our unit in 2012 in cardiac arrest as a result of a rupture of the distal graft suture line due to infection. After resuscitation he underwent aorto-bifemoral grafting using a cuff of the original aortic graft proximally. Distally the new graft was anastomosed to his common femoral arteries, with gentamicin beads left in situ. Post discharge the patient was kept under close surveillance with serial investigations including nuclear scanning, however it became apparent that his new graft was infected and that he would require aortic graft replacement, an operation with a mortality of at least 50%. The patient underwent the operation and findings confirmed a synthetic graft infection. This tube graft was explanted and a cryopreserved aorta was used to the refashion the abdominal aorta and its bifurcation. The operation required a return to theatre day one post operatively for a bleeding side branch, which was repaired. The patient went on to make a full recovery stepping down from the intensive therapy unit day 6 post operatively and went on to be discharged 32 days after his cryopreserved aorta implantation. PMID:27351624

  11. Proximal Sciatic Nerve Intraneural Ganglion Cyst

    PubMed Central

    Swartz, Karin R.; Wilson, Dianne; Boland, Michael; Fee, Dominic B.

    2009-01-01

    Intraneural ganglion cysts are nonneoplastic, mucinous cysts within the epineurium of peripheral nerves which usually involve the peroneal nerve at the knee. A 37-year-old female presented with progressive left buttock and posterior thigh pain. Magnetic resonance imaging revealed a sciatic nerve mass at the sacral notch which was subsequently revealed to be an intraneural ganglion cyst. An intraneural ganglion cyst confined to the proximal sciatic nerve has only been reported once prior to 2009. PMID:20069041

  12. Patterned substrates and methods for nerve regeneration

    DOEpatents

    Mallapragada, Surya K.; Heath, Carole; Shanks, Howard; Miller, Cheryl A.; Jeftinija, Srdija

    2004-01-13

    Micropatterned substrates and methods for fabrication of artificial nerve regeneration conduits and methods for regenerating nerves are provided. Guidance compounds or cells are seeded in grooves formed on the patterned substrate. The substrates may also be provided with electrodes to provide electrical guidance cues to the regenerating nerve. The micropatterned substrates give physical, chemical, cellular and/or electrical guidance cues to promote nerve regeneration at the cellular level.

  13. Overview of Optic Nerve Disorders

    MedlinePlus

    ... pathways to the brain results in loss of vision. At a structure in the brain called the optic chiasm, each optic nerve splits, ... both eyes, and the left side of the brain receives information from the right visual field of both eyes. ... occurs. Resources ...

  14. Outcome following spinal accessory to suprascapular (spinoscapular) nerve transfer in infants with brachial plexus birth injuries.

    PubMed

    Ruchelsman, David E; Ramos, Lorna E; Alfonso, Israel; Price, Andrew E; Grossman, Agatha; Grossman, John A I

    2010-06-01

    The purpose of this study is to evaluate the value of distal spinal accessory nerve (SAN) transfer to the suprascapular nerve (SSN) in children with brachial plexus birth injuries in order to better define the application and outcome of this transfer in these infants. Over a 3-year period, 34 infants with brachial plexus injuries underwent transfer of the SAN to the SSN as part of the primary surgical reconstruction. Twenty-five patients (direct repair, n = 20; interposition graft, n = 5) achieved a minimum follow-up of 24 months. Fourteen children underwent plexus reconstruction with SAN-to-SSN transfer at less than 9 months of age, and 11 underwent surgical reconstruction at the age of 9 months or older. Mean age at the time of nerve transfer was 11.6 months (range, 5-30 months). At latest follow-up, active shoulder external rotation was measured in the arm abducted position and confirmed by review of videos. The Gilbert and Miami shoulder classification scores were utilized to report shoulder-specific functional outcomes. The effects of patie