Biochemical Monitoring of Spinal Cord Injury by FT-IR Spectroscopy--Effects of Therapeutic Alginate Implant in Rat Models.

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Sandra Tamosaityte

Full Text Available Spinal cord injury (SCI induces complex biochemical changes, which result in inhibition of nervous tissue regeneration abilities. In this study, Fourier-transform infrared (FT-IR spectroscopy was applied to assess the outcomes of implants made of a novel type of non-functionalized soft calcium alginate hydrogel in a rat model of spinal cord hemisection (n = 28. Using FT-IR spectroscopic imaging, we evaluated the stability of the implants and the effects on morphology and biochemistry of the injured tissue one and six months after injury. A semi-quantitative evaluation of the distribution of lipids and collagen showed that alginate significantly reduced injury-induced demyelination of the contralateral white matter and fibrotic scarring in the chronic state after SCI. The spectral information enabled to detect and localize the alginate hydrogel at the lesion site and proved its long-term persistence in vivo. These findings demonstrate a positive impact of alginate hydrogel on recovery after SCI and prove FT-IR spectroscopic imaging as alternative method to evaluate and optimize future SCI repair strategies.

Improvement of renal function after human umbilical cord mesenchymal stem cell treatment on chronic renal failure and thoracic spinal cord entrapment: a case report.

Science.gov (United States)

Rahyussalim, Ahmad Jabir; Saleh, Ifran; Kurniawati, Tri; Lutfi, Andi Praja Wira Yudha

2017-11-30

Chronic renal failure is an important clinical problem with significant socioeconomic impact worldwide. Thoracic spinal cord entrapment induced by a metabolic yield deposit in patients with renal failure results in intrusion of nervous tissue and consequently loss of motor and sensory function. Human umbilical cord mesenchymal stem cells are immune naïve and they are able to differentiate into other phenotypes, including the neural lineage. Over the past decade, advances in the field of regenerative medicine allowed development of cell therapies suitable for kidney repair. Mesenchymal stem cell studies in animal models of chronic renal failure have uncovered a unique potential of these cells for improving function and regenerating the damaged kidney. We report a case of a 62-year-old ethnic Indonesian woman previously diagnosed as having thoracic spinal cord entrapment with paraplegic condition and chronic renal failure on hemodialysis. She had diabetes mellitus that affected her kidneys and had chronic renal failure for 2 years, with creatinine level of 11 mg/dl, and no urinating since then. She was treated with human umbilical cord mesenchymal stem cell implantation protocol. This protocol consists of implantation of 16 million human umbilical cord mesenchymal stem cells intrathecally and 16 million human umbilical cord mesenchymal stem cells intravenously. Three weeks after first intrathecal and intravenous implantation she could move her toes and her kidney improved. Her creatinine level decreased to 9 mg/dl. Now after 8 months she can raise her legs and her creatinine level is 2 mg/dl with normal urinating. Human umbilical cord mesenchymal stem cell implantations led to significant improvement for spinal cord entrapment and kidney failure. The major histocompatibility in allogeneic implantation is an important issue to be addressed in the future.

Magnetic resonance imaging susceptibility artifacts in the cervical vertebrae and spinal cord related to monocortical screw-polymethylmethacrylate implants in canine cadavers.

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Jones, Brian G; Fosgate, Geoffrey T; Green, Eric M; Habing, Amy M; Hettlich, Bianca F

2017-04-01

OBJECTIVE To characterize and compare MRI susceptibility artifacts related to titanium and stainless steel monocortical screws in the cervical vertebrae and spinal cord of canine cadavers. SAMPLE 12 canine cadavers. PROCEDURES Cervical vertebrae (C4 and C5) were surgically stabilized with titanium or stainless steel monocortical screws and polymethylmethacrylate. Routine T1-weighted, T2-weighted, and short tau inversion recovery sequences were performed at 3.0 T. Magnetic susceptibility artifacts in 20 regions of interest (ROIs) across 4 contiguous vertebrae (C3 through C6) were scored by use of an established scoring system. RESULTS Artifact scores for stainless steel screws were significantly greater than scores for titanium screws at 18 of 20 ROIs. Artifact scores for titanium screws were significantly higher for spinal cord ROIs within the implanted vertebrae. Artifact scores for stainless steel screws at C3 were significantly less than at the other 3 cervical vertebrae. CONCLUSIONS AND CLINICAL RELEVANCE Evaluation of routine MRI sequences obtained at 3.0 T revealed that susceptibility artifacts related to titanium monocortical screws were considered mild and should not hinder the overall clinical assessment of the cervical vertebrae and spinal cord. However, mild focal artifacts may obscure small portions of the spinal cord or intervertebral discs immediately adjacent to titanium screws. Severe artifacts related to stainless steel screws were more likely to result in routine MRI sequences being nondiagnostic; however, artifacts may be mitigated by implant positioning.

A Fully Implantable Stimulator With Wireless Power and Data Transmission for Experimental Investigation of Epidural Spinal Cord Stimulation.

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Xu, Qi; Hu, Dingyin; Duan, Bingyu; He, Jiping

2015-07-01

Epidural spinal cord stimulation (ESCS) combined with partial weight-bearing therapy (PWBT) has been shown to facilitate recovery of functional walking for individuals after spinal cord injury (SCI). The investigation of neural mechanisms of recovery from SCI under this treatment has been conducted broadly in rodent models, yet a suitable ESCS system is still unavailable. This paper describes a practical, programmable, and fully implantable stimulator for laboratory research on rats to explore fundamental neurophysiological principles for functional recovery after SCI. The ESCS system is composed of a personal digital assistant (PDA), an external controller, an implantable pulse generator (IPG), lead extension, and stimulating electrodes. The stimulation parameters can be programmed and adjusted through a graphical user interface on the PDA. The external controller is placed on the rat back and communicates with the PDA via radio-frequency (RF) telemetry. An RF carrier from the class-E power amplifier in the external controller provides both data and power for the IPG through an inductive link. The IPG is built around a microcontroller unit to generate voltage-regulated pulses delivered to the bipolar electrode for ESCS in rats. The encapsulated IPG measures 22 mm × 23 mm × 7 mm with a mass of  ∼  3.78 g. This fully implantable batteryless stimulator provided a simplified and efficient method to carry out chronic experiments in untethered animals for medical electro-neurological research.

A spinal cord window chamber model for in vivo longitudinal multimodal optical and acoustic imaging in a murine model.

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Sarah A Figley

Full Text Available In vivo and direct imaging of the murine spinal cord and its vasculature using multimodal (optical and acoustic imaging techniques could significantly advance preclinical studies of the spinal cord. Such intrinsically high resolution and complementary imaging technologies could provide a powerful means of quantitatively monitoring changes in anatomy, structure, physiology and function of the living cord over time after traumatic injury, onset of disease, or therapeutic intervention. However, longitudinal in vivo imaging of the intact spinal cord in rodent models has been challenging, requiring repeated surgeries to expose the cord for imaging or sacrifice of animals at various time points for ex vivo tissue analysis. To address these limitations, we have developed an implantable spinal cord window chamber (SCWC device and procedures in mice for repeated multimodal intravital microscopic imaging of the cord and its vasculature in situ. We present methodology for using our SCWC to achieve spatially co-registered optical-acoustic imaging performed serially for up to four weeks, without damaging the cord or induction of locomotor deficits in implanted animals. To demonstrate the feasibility, we used the SCWC model to study the response of the normal spinal cord vasculature to ionizing radiation over time using white light and fluorescence microscopy combined with optical coherence tomography (OCT in vivo. In vivo power Doppler ultrasound and photoacoustics were used to directly visualize the cord and vascular structures and to measure hemoglobin oxygen saturation through the complete spinal cord, respectively. The model was also used for intravital imaging of spinal micrometastases resulting from primary brain tumor using fluorescence and bioluminescence imaging. Our SCWC model overcomes previous in vivo imaging challenges, and our data provide evidence of the broader utility of hybridized optical-acoustic imaging methods for obtaining

Therapeutic effects of NogoA vaccine and olfactory ensheathing glial cell implantation on acute spinal cord injury

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Zhang Z

2013-10-01

Full Text Available Zhicheng Zhang, Fang Li, Tiansheng Sun, Dajiang Ren, Xiumei Liu PLA Institute of Orthopedics, Beijing Army General Hospital, Beijing, People's Republic of China Background: Many previous studies have focused on the effects of IN-1, a monoclonal antibody that neutralizes Nogo (a neurite growth inhibitory protein, on neurologic regeneration in spinal cord injury (SCI. However, safety problems and the short half-life of the exogenous antibody are still problematic. In the present study, the NogoA polypeptide was used as an antigen to make a therapeutic NogoA vaccine. Rats were immunized with this vaccine and were able to secrete the polyclonal antibody before SCI. The antibody can block NogoA within the injured spinal cord when the antibody gains access to the spinal cord due to a compromised blood–spinal cord barrier. Olfactory ensheathing glial cell transplantation has been used in a spinal cord contusion model to promote the recovery of SCI. The present study was designed to verify the efficacy and safety of NogoA polypeptide vaccine, the effects of immunotherapy with this vaccine, and the synergistic effects of the vaccine and olfactory ensheathing glial cells in repair of SCI. Methods: A 13-polypeptide fragment of NogoA was synthesized. This fragment was then coupled with keyhole limpet hemocyanin to improve the immunogenicity of the polypeptide vaccine. Immunization via injection into the abdominal cavity was performed in rats before SCI. The serum antibody level and ability of the vaccine to bind with Nogo were detected by enzyme-linked immunosorbent assay. The safety of the vaccine was evaluated according to the incidence and severity of experimental autoimmune encephalomyelitis. Olfactory ensheathing glia cells were obtained, purified, and subsequently implanted into a Wistar rat model of thoracic spinal cord contusion injury. The rats were divided into four groups, ie, an SCI model group, an olfactory ensheathing glia group, a vaccine

Spinal cord atrophy in anterior-posterior direction reflects impairment in multiple sclerosis

DEFF Research Database (Denmark)

Lundell, H; Svolgaard, O; Dogonowski, A-M

2017-01-01

OBJECTIVE: To investigate how atrophy is distributed over the cross section of the upper cervical spinal cord and how this relates to functional impairment in multiple sclerosis (MS). METHODS: We analysed the structural brain MRI scans of 54 patients with relapsing-remitting MS (n=22), primary...... progressive MS (n=9), secondary progressive MS (n=23) and 23 age- and sex-matched healthy controls. We measured the cross-sectional area (CSA), left-right width (LRW) and anterior-posterior width (APW) of the spinal cord at the segmental level C2. We tested for a nonparametric linear relationship between...... and specific MSIS subscores. CONCLUSION: In patients with MS, atrophy of the upper cervical cord is most evident in the antero-posterior direction. As APW of the cervical cord can be readily derived from standard structural MRI of the brain, APW constitutes a clinically useful neuroimaging marker of disease...

A Brain–Spinal Interface Alleviating Gait Deficits after Spinal Cord Injury in Primates

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Capogrosso, Marco; Milekovic, Tomislav; Borton, David; Wagner, Fabien; Moraud, Eduardo Martin; Mignardot, Jean-Baptiste; Buse, Nicolas; Gandar, Jerome; Barraud, Quentin; Xing, David; Rey, Elodie; Duis, Simone; Jianzhong, Yang; Ko, Wai Kin D.; Li, Qin; Detemple, Peter; Denison, Tim; Micera, Silvestro; Bezard, Erwan; Bloch, Jocelyne; Courtine, Grégoire

2016-01-01

Spinal cord injury disrupts the communication between the brain and the spinal circuits that orchestrate movement. To bypass the lesion, brain–computer interfaces1–3 have directly linked cortical activity to electrical stimulation of muscles, which have restored grasping abilities after hand paralysis1,4. Theoretically, this strategy could also restore control over leg muscle activity for walking5. However, replicating the complex sequence of individual muscle activation patterns underlying natural and adaptive locomotor movements poses formidable conceptual and technological challenges6,7. Recently, we showed in rats that epidural electrical stimulation of the lumbar spinal cord can reproduce the natural activation of synergistic muscle groups producing locomotion8–10. Here, we interfaced leg motor cortex activity with epidural electrical stimulation protocols to establish a brain–spinal interface that alleviated gait deficits after a spinal cord injury in nonhuman primates. Rhesus monkeys were implanted with an intracortical microelectrode array into the leg area of motor cortex; and a spinal cord stimulation system composed of a spatially selective epidural implant and a pulse generator with real-time triggering capabilities. We designed and implemented wireless control systems that linked online neural decoding of extension and flexion motor states with stimulation protocols promoting these movements. These systems allowed the monkeys to behave freely without any restrictions or constraining tethered electronics. After validation of the brain–spinal interface in intact monkeys, we performed a unilateral corticospinal tract lesion at the thoracic level. As early as six days post-injury and without prior training of the monkeys, the brain–spinal interface restored weight-bearing locomotion of the paralyzed leg on a treadmill and overground. The implantable components integrated in the brain–spinal interface have all been approved for investigational

Microphone directionality, pre-emphasis filter, and wind noise in cochlear implants.

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Chung, King; McKibben, Nicholas

2011-10-01

Wind noise can be a nuisance or a debilitating masker for cochlear implant users in outdoor environments. Previous studies indicated that wind noise at the microphone/hearing aid output had high levels of low-frequency energy and the amount of noise generated is related to the microphone directionality. Currently, cochlear implants only offer either directional microphones or omnidirectional microphones for users at-large. As all cochlear implants utilize pre-emphasis filters to reduce low-frequency energy before the signal is encoded, effective wind noise reduction algorithms for hearing aids might not be applicable for cochlear implants. The purposes of this study were to investigate the effect of microphone directionality on speech recognition and perceived sound quality of cochlear implant users in wind noise and to derive effective wind noise reduction strategies for cochlear implants. A repeated-measure design was used to examine the effects of spectral and temporal masking created by wind noise recorded through directional and omnidirectional microphones and the effects of pre-emphasis filters on cochlear implant performance. A digital hearing aid was programmed to have linear amplification and relatively flat in-situ frequency responses for the directional and omnidirectional modes. The hearing aid output was then recorded from 0 to 360° at flow velocities of 4.5 and 13.5 m/sec in a quiet wind tunnel. Sixteen postlingually deafened adult cochlear implant listeners who reported to be able to communicate on the phone with friends and family without text messages participated in the study. Cochlear implant users listened to speech in wind noise recorded at locations that the directional and omnidirectional microphones yielded the lowest noise levels. Cochlear implant listeners repeated the sentences and rated the sound quality of the testing materials. Spectral and temporal characteristics of flow noise, as well as speech and/or noise characteristics before

Spinal cord stimulation: Background and clinical application

DEFF Research Database (Denmark)

Meier, Kaare

2014-01-01

a number of contacts capable of delivering a weak electrical current to the spinal cord, evoking a feeling of peripheral paresthesia. With correct indication and if implanted by an experienced implanter, success rates generally are in the range of about 50–75%. Common indications include complex regional...

Advantages of soft subdural implants for the delivery of electrochemical neuromodulation therapies to the spinal cord

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Capogrosso, Marco; Gandar, Jerome; Greiner, Nathan; Moraud, Eduardo Martin; Wenger, Nikolaus; Shkorbatova, Polina; Musienko, Pavel; Minev, Ivan; Lacour, Stephanie; Courtine, Grégoire

2018-04-01

Objective. We recently developed soft neural interfaces enabling the delivery of electrical and chemical stimulation to the spinal cord. These stimulations restored locomotion in animal models of paralysis. Soft interfaces can be placed either below or above the dura mater. Theoretically, the subdural location combines many advantages, including increased selectivity of electrical stimulation, lower stimulation thresholds, and targeted chemical stimulation through local drug delivery. However, these advantages have not been documented, nor have their functional impact been studied in silico or in a relevant animal model of neurological disorders using a multimodal neural interface. Approach. We characterized the recruitment properties of subdural interfaces using a realistic computational model of the rat spinal cord that included explicit representation of the spinal roots. We then validated and complemented computer simulations with electrophysiological experiments in rats. We additionally performed behavioral experiments in rats that received a lateral spinal cord hemisection and were implanted with a soft interface. Main results. In silico and in vivo experiments showed that the subdural location decreased stimulation thresholds compared to the epidural location while retaining high specificity. This feature reduces power consumption and risks of long-term damage in the tissues, thus increasing the clinical safety profile of this approach. The hemisection induced a transient paralysis of the leg ipsilateral to the injury. During this period, the delivery of electrical stimulation restricted to the injured side combined with local chemical modulation enabled coordinated locomotor movements of the paralyzed leg without affecting the non-impaired leg in all tested rats. Electrode properties remained stable over time, while anatomical examinations revealed excellent bio-integration properties. Significance. Soft neural interfaces inserted subdurally provide the

Implantable porous gelatin microspheres sustained release of bFGF and improved its neuroprotective effect on rats after spinal cord injury.

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Li Lan

Full Text Available In this study, porous gelatin microspheres (GMSs were constructed to improve the neuroprotective effect of basic fibroblast growth factor (bFGF on spinal cord injury. GMSs were prepared by a W/O emulsion template, followed by cross-linking, washing and drying. The particle sizes and surface porosity of the blank GMSs were carefully characterized by scan electronic microscopy. The blank GMSs have a mean particle size of 35μm and theirs surface was coarse and porous. bFGF was easily encapsulated inside the bulk GMSs through diffusion along the porous channel. 200μg of bFGF was completely encapsulated in 100mg of GMSs. The bFGF-loaded GMSs displayed a continuous drug release pattern without an obvious burst release over two weeks in vitro. Moreover, the therapeutic effects of bFGF-loaded GMSs were also evaluated in spinal cord injury rat model. After implantation of bFGF-loaded GMSs, the recovery of the motor function of SCI rats were evaluated by behavioral score and foot print experiment. The motor function of SCI rats treated with bFGF-loaded GMSs was more obvious than that treated with free bFGF solution (P<0.05. At the 28th days after treatment, rats were sacrificed and the injured spinal were removed for histopathological and apoptosis examination. Compared with treatment with free bFGF solution, treatment with bFGF-loaded GMSs resulted in a less necrosis, less infiltration of leukocytes, and a reduced the cavity ratio and less apoptotic cells in injured spinal(P<0.01, indicating its better therapeutic effect. Implantable porous GMSs may be a potential carrier to deliver bFGF for therapy of spinal cord injury.

Spinal cord atrophy in anterior-posterior direction reflects impairment in multiple sclerosis.

Science.gov (United States)

Lundell, H; Svolgaard, O; Dogonowski, A-M; Romme Christensen, J; Selleberg, F; Soelberg Sørensen, P; Blinkenberg, M; Siebner, H R; Garde, E

2017-10-01

To investigate how atrophy is distributed over the cross section of the upper cervical spinal cord and how this relates to functional impairment in multiple sclerosis (MS). We analysed the structural brain MRI scans of 54 patients with relapsing-remitting MS (n=22), primary progressive MS (n=9), secondary progressive MS (n=23) and 23 age- and sex-matched healthy controls. We measured the cross-sectional area (CSA), left-right width (LRW) and anterior-posterior width (APW) of the spinal cord at the segmental level C2. We tested for a nonparametric linear relationship between these atrophy measures and clinical impairments as reflected by the Expanded Disability Status Scale (EDSS) and Multiple Sclerosis Impairment Scale (MSIS). In patients with MS, CSA and APW but not LRW were reduced compared to healthy controls (P<.02) and showed significant correlations with EDSS, MSIS and specific MSIS subscores. In patients with MS, atrophy of the upper cervical cord is most evident in the antero-posterior direction. As APW of the cervical cord can be readily derived from standard structural MRI of the brain, APW constitutes a clinically useful neuroimaging marker of disease-related neurodegeneration in MS. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Immediate Direct-To-Implant Breast Reconstruction Using Anatomical Implants

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Sung-Eun Kim

2014-09-01

Full Text Available BackgroundIn 2012, a new anatomic breast implant of form-stable silicone gel was introduced onto the Korean market. The intended use of this implant is in the area of aesthetic breast surgery, and many reports are promising. Thus far, however, there have been no reports on the use of this implant for breast reconstruction in Korea. We used this breast implant in breast reconstruction surgery and report our early experience.MethodsFrom November 2012 to April 2013, the Natrelle Style 410 form-stable anatomically shaped cohesive silicone gel-filled breast implant was used in 31 breasts of 30 patients for implant breast reconstruction with an acellular dermal matrix. Patients were treated with skin-sparing mastectomies followed by immediate breast reconstruction.ResultsThe mean breast resection volume was 240 mL (range, 83-540 mL. The mean size of the breast implants was 217 mL (range, 125-395 mL. Breast shape outcomes were considered acceptable. Infection and skin thinning occurred in one patient each, and hematoma and seroma did not occur. Three cases of wound dehiscence occurred, one requiring surgical intervention, while the others healed with conservative treatment in one month. Rippling did not occur. So far, complications such as capsular contracture and malrotation of breast implant have not yet arisen.ConclusionsBy using anatomic breast implants in breast reconstruction, we achieved satisfactory results with aesthetics better than those obtained with round breast implants. Therefore, we concluded that the anatomical implant is suitable for breast reconstruction.

Fin field effect transistor directionality impacts printing of implantation shapes

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Wang, Xiren; Granik, Yuri

2018-01-01

In modern integrated circuit (IC) fabrication processes, the photoresist receives considerable illumination energy that is reflected by underlying topography during optical lithography of implantation layers. Bottom antireflective coating (BARC) is helpful to mitigate the reflection. Often, however, BARC is not used, because its removal is technically challenging, in addition to its relatively high economic cost. Furthermore, the advanced technology nodes, such as 14/10-nm nodes, have introduced fin field effect transistor (FinFET), which makes reflection from nonuniform silicon substrates exceptionally complicated. Therefore, modeling reflection from topography becomes obligatory to accurately predict printing of implantation shapes. Typically, FinFET is always fixed in one direction in realistic designs. However, the same implantation rectangle may be oriented in either horizontal or vertical direction. Then, there are two types of relations between the critical dimension (CD) and FinFET, namely a parallel-to and a perpendicular-to relation. We examine the fin directionality impact on CD. We found that this impact may be considerable in some cases. We use our in-house rigorous optical topography simulator to reveal underlining physical reasons. One of the major causes of the CD differences is that in the parallel orientation, the solid sidewalls of the fins conduct considerable light reflections unlike for the perpendicular orientation. This finding can aid the compact modeling in optical proximity correction of implantation masks.

A Limited Submuscular Direct-to-Implant Technique Utilizing AlloMax

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Michal Brichacek, MD

2017-07-01

Full Text Available Background:. This study evaluates a novel limited submuscular direct-to-implant technique utilizing AlloMax where only the upper few centimeters of the implant is covered by the pectoralis, whereas the majority of the implant including the middle and lower poles are covered by acellular dermal matrix. Methods:. The pectoralis muscle is released off its inferior and inferior-medial origins and allowed to retract superiorly. Two sheets of AlloMax (6 × 16 cm are sutured together and secured to the inframammary fold, serratus fascia, and the superiorly retracted pectoralis. Thirty-seven breasts in 19 consecutive patients with follow-up at 6 months were reviewed. Results:. Nineteen consecutive patients with 37 reconstructed breasts were studied. Average age was 50 years, average BMI was 24.3. Ptosis ranged from grade 0–III, and average cup size was B (range, A–DDD. Early minor complications included 1 seroma, 3 minor postoperative hematomas managed conservatively, and 3 minor wound healing problems. Three breasts experienced mastectomy skin flap necrosis and were managed with local excision. There were no cases of postoperative infection, red breast, grade III/IV capsular contractures, or implant loss. A single patient complained of animation postoperatively. One patient desired fat grafting for rippling. Conclusions:. The limited submuscular direct-to-implant technique utilizing AlloMax appears to be safe with a low complication rate at 6 months. This technique minimizes the action of the pectoralis on the implant, reducing animation deformities but still providing muscle coverage of the upper limit of the implant. Visible rippling is reduced, and a vascularized bed remains for fat grafting of the upper pole if required.

Caesarean section in a parturient with a spinal cord stimulator.

LENUS (Irish Health Repository)

Sommerfield, D

2010-01-01

A 35-year-old G2P1 parturient at 32 weeks of gestation with an implanted spinal cord stimulator was admitted for urgent caesarean section. Spinal anaesthesia was performed below the spinal cord stimulator leads at the L4-5 level, and a healthy female infant was delivered. A basic description of the technology and resulting implications for the parturient are discussed.

Ex vivo adenoviral vector-mediated neurotrophin gene transfer to olfactory ensheathing glia : effects on rubrospinal tract regeneration, lesion size, and functional recovery after implantation in the injured rat spinal cord

NARCIS (Netherlands)

Ruitenberg, Marc J; Plant, Giles W; Hamers, Frank P T; Wortel, Joke; Blits, Bas; Dijkhuizen, Paul A; Gispen, Willem Hendrik; Boer, Gerard J; Verhaagen, J.

2003-01-01

The present study uniquely combines olfactory ensheathing glia (OEG) implantation with ex vivo adenoviral (AdV) vector-based neurotrophin gene therapy in an attempt to enhance regeneration after cervical spinal cord injury. Primary OEG were transduced with AdV vectors encoding rat brain-derived

Implantable medical electronics prosthetics, drug delivery, and health monitoring

CERN Document Server

Khanna, Vinod Kumar

2016-01-01

This book is a comprehensive, interdisciplinary resource for the latest information on implantable medical devices, and is intended for graduate students studying electrical engineering, electronic instrumentation, and biomedical engineering. It is also appropriate for academic researchers, professional engineers, practicing doctors, and paramedical staff. Divided into two sections on Basic Concepts and Principles, and Applications, the first section provides an all-embracing perspective of the electronics background necessary for this work. The second section deals with pacing techniques used for the heart, brain, spinal cord, and the network of nerves that interlink the brain and spinal cord with the major organs, including ear and eye prostheses. The four main offshoots of implantable electronics, which this book discusses, are: The insertion of an implantable neural amplifier for accurate recording of neural signals for neuroengineering studies The use of implantable pulse generators for pacing the activi...

Cetuximab modified collagen scaffold directs neurogenesis of injury-activated endogenous neural stem cells for acute spinal cord injury repair.

Science.gov (United States)

Li, Xing; Zhao, Yannan; Cheng, Shixiang; Han, Sufang; Shu, Muya; Chen, Bing; Chen, Xuyi; Tang, Fengwu; Wang, Nuo; Tu, Yue; Wang, Bin; Xiao, Zhifeng; Zhang, Sai; Dai, Jianwu

2017-08-01

Studies have shown that endogenous neural stem cells (NSCs) activated by spinal cord injury (SCI) primarily generate astrocytes to form glial scar. The NSCs do not differentiate into neurons because of the adverse microenvironment. In this study, we defined the activation timeline of endogenous NSCs in rats with severe SCI. These injury-activated NSCs then migrated into the lesion site. Cetuximab, an EGFR signaling antagonist, significantly increased neurogenesis in the lesion site. Meanwhile, implanting cetuximab modified linear ordered collagen scaffolds (LOCS) into SCI lesion sites in dogs resulted in neuronal regeneration, including neuronal differentiation, maturation, myelination, and synapse formation. The neuronal regeneration eventually led to a significant locomotion recovery. Furthermore, LOCS implantation could also greatly decrease chondroitin sulfate proteoglycan (CSPG) deposition at the lesion site. These findings suggest that endogenous neurogenesis following acute complete SCI is achievable in species ranging from rodents to large animals via functional scaffold implantation. LOCS-based Cetuximab delivery system has a promising therapeutic effect on activating endogenous neurogenesis, reducing CSPGs deposition and improving motor function recovery. Copyright © 2017 Elsevier Ltd. All rights reserved.

Braided multi-electrode probes: mechanical compliance characteristics and recordings from spinal cords

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Kim, Taegyo; Branner, Almut; Gulati, Tanuj; Giszter, Simon F.

2013-08-01

Objective. To test a novel braided multi-electrode probe design with compliance exceeding that of a 50 µm microwire, thus reducing micromotion- and macromotion-induced tissue stress. Approach. We use up to 24 ultra-fine wires interwoven into a tubular braid to obtain a highly flexible multi-electrode probe. The tether-portion wires are simply non-braided extensions of the braid structure, allowing the microprobe to follow gross neural tissue movements. Mechanical calculation and direct measurements evaluated bending stiffness and axial compression forces in the probe and tether system. These were compared to 50 µm nichrome microwire standards. Recording tests were performed in decerebrate animals. Main results. Mechanical bending tests on braids comprising 9.6 or 12.7 µm nichrome wires showed that implants (braided portions) had 4 to 21 times better mechanical compliance than a single 50 µm wire and non-braided tethers were 6 to 96 times better. Braided microprobes yielded robust neural recordings from animals' spinal cords throughout cord motions. Significance. Microwire electrode arrays that can record and withstand tissue micro- and macromotion of spinal cord tissues are demonstrated. This technology may provide a stable chronic neural interface into spinal cords of freely moving animals, is extensible to various applications, and may reduce mechanical tissue stress.

[Imaging of alloplastic ligament implant. An in vivo and in vitro study exemplified by Kevlar].

Science.gov (United States)

Wening, J V; Katzer, A; Nicolas, V; Hahn, M; Jungbluth, K H; Kratzer A [corrected to Katzer, A

1994-04-01

Neither native X-ray nor CT or NMR allow to evaluate intraarticular implantation results of Kevlar -49 directly. In animal trials, the course of an artificial ligament may only be presumed from connective tissue ingrowth. Although soft tissue structure appears much better in NMR than in CT, direct proof of ligament continuity is still impossible. As soon as the connective tissue becomes continuous, it appears clearly and allows indirect evaluation of the prosthesis, as integrity can be judged by its shape like in natural cruciate ligament. Anatomic preparations show that connective tissue fills up the small space between the two cords of a Kevlar -49 two bundle prosthesis eight weeks after implantation, so that imaging systems show only one intraarticular bundle.

Injury-induced ctgfa directs glial bridging and spinal cord regeneration in zebrafish

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Mokalled, Mayssa H.; Patra, Chinmoy; Dickson, Amy L.; Endo, Toyokazu; Stainier, Didier Y. R.; Poss, Kenneth D.

2016-01-01

Unlike mammals, zebrafish efficiently regenerate functional nervous system tissue after major spinal cord injury. Whereas glial scarring presents a roadblock for mammalian spinal cord repair, glial cells in zebrafish form a bridge across severed spinal cord tissue and facilitate regeneration, a relatively unexplored process. Here, we performed a genome-wide profiling screen for secreted factors that are upregulated during zebrafish spinal cord regeneration. We find that connective tissue growth factor a (ctgfa) is induced in and around glial cells that participate in initial bridging events. Mutations in ctgfa disrupt spinal cord repair, while transgenic ctgfa overexpression and local human CTGF recombinant protein delivery accelerate bridging and functional regeneration. Our study reveals that CTGF is necessary and sufficient to stimulate glial bridging and natural spinal cord regeneration. PMID:27811277

Quasi-static strength and fractography analysis of two dental implants manufactured by direct metal laser sintering.

Science.gov (United States)

Gehrke, Sergio Alexandre; Pérez-Díaz, Leticia; Dedavid, Berenice Anina

2018-01-30

New manufacturing methods was developed to improve the tissues integration with the titanium alloy pieces. The present in vitro study was to assess the resistance and fracture mode after applied a quasi-static compressive force on the two dental implants manufactured by direct metal laser sintering. Twenty dental implants manufactured by direct metal laser sintering, using titanium alloy (Ti-6Al-4V) granules in two designs (n = 10 per group): Conventional dental implant (group Imp1) two-piece implant design, where the surgical implant and prosthetic abutment are two separate components and, the one-piece implant (group Imp2), where the surgical implant and prosthetic abutment are one integral piece. All samples were subjected to quasi-static loading at a 30° angle to the implant axis in a universal testing machine. The mean fracture strengths were 1269.2 ± 128.8 N for the group Imp1 and, 1259.5 ± 115.1 N for the group Imp2, without statistical differences (P = .8722). In both groups, the fracture surface does not present crack between the compact core and the superficial (less dense and porous) part of the implants. Based on the measured resistance data for the two implant models manufactured by direct metal laser sintering tested in the present study, we can suggest that they have adequate capacity to withstand the masticatory loads. © 2018 Wiley Periodicals, Inc.

An intermediate animal model of spinal cord stimulation

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Thomas Guiho

2016-06-01

Full Text Available Spinal cord injuries (SCI result in the loss of movement and sensory feedback as well as organs dysfunctions. For example, nearly all SCI subjects loose their bladder control and are prone to kidney failure if they do not proceed to intermittent (self- catheterization. Electrical stimulation of the sacral spinal roots with an implantable neuroprosthesis is a promising approach, with commercialized products, to restore continence and control micturition. However, many persons do not ask for this intervention since a surgical deafferentation is needed and the loss of sensory functions and reflexes become serious side effects of this procedure. Recent results renewed interest in spinal cord stimulation. Stimulation of existing pre-cabled neural networks involved in physiological processes regulation is suspected to enable synergic recruitment of spinal fibers. The development of direct spinal stimulation strategies aiming at bladder and bowel functions restoration would therefore appear as a credible alternative to existent solutions. However, a lack of suitable large animal model complicates these kinds of studies. In this article, we propose a new animal model of spinal stimulation -pig- and will briefly introduce results from one first acute experimental validation session.

Complications related to the use of spinal cord stimulation for managing persistent postoperative neuropathic pain after lumbar spinal surgery.

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Shamji, Mohammed F; Westwick, Harrison J; Heary, Robert F

2015-10-01

OBJECT Structural spinal surgery yields improvement in pain and disability for selected patients with spinal stenosis, spondylolisthesis, or a herniated intervertebral disc. A significant fraction of patients exhibit persistent postoperative neuropathic pain (PPNP) despite technically appropriate intervention, and such patients can benefit from spinal cord stimulation (SCS) to alleviate suffering. The complication profile of this therapy has not been systematically assessed and, thus, was the goal of this review. METHODS A comprehensive literature search was performed to identify prospective cohorts of patients who had PPNP following structurally corrective lumbar spinal surgery and who underwent SCS device implantation. Data about study design, technique of SCS lead introduction, and complications encountered were collected and analyzed. Comparisons of complication incidence were performed between percutaneously and surgically implanted systems, with the level of significance set at 0.05. RESULTS Review of 11 studies involving 542 patients formed the basis of this work: 2 randomized controlled trials and 9 prospective cohorts. Percutaneous implants were used in 4 studies and surgical implants were used in 4 studies; in the remainder, the types were undefined. Lead migration occurred in 12% of cases, pain at the site of the implantable pulse generator occurred in 9% of cases, and wound-related complications occurred in 5% of cases; the latter 2 occurred more frequently among surgically implanted devices. CONCLUSIONS Spinal cord stimulation can provide for improved pain and suffering and for decreased narcotic medication use among patients with PPNP after lumbar spinal surgery. This study reviewed the prospective studies forming the evidence base for this therapy, to summarize the complications encountered and, thus, best inform patients and clinicians considering its use. There is a significant rate of minor complications, many of which require further surgical

Transverse tripolar spinal cord stimulation: results of an international multicenter study.

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Oakley, John C; Espinosa, Francisco; Bothe, Hans; McKean, John; Allen, Peter; Burchiel, Kim; Quartey, Gilbert; Spincemaille, Geert; Nuttin, Bart; Gielen, Frans; King, Gary; Holsheimer, Jan

2006-07-01

Experienced neurosurgeons at eight spinal cord stimulation centers in the United States, Canada, and Europe participated in a study from 1997 to 2000 investigating the safety, performance, and efficacy of a Transverse Tripolar Stimulation (TTS) system invented at the University of Twente, the Netherlands. This device was proposed to improve the ability of spinal cord stimulation to adequately overlap paresthesia to perceived areas of pain. Fifty-six patients with chronic, intractable neuropathic pain of the trunk and/or limbs more than three months' duration (average 105 months) were enrolled with follow-up periods at 4, 12, 26, and 52 weeks. All patients had a new paddle-type lead implanted with four electrodes, three of them aligned in a row perpendicular to the cord. Fifteen of these patients did not undergo permanent implantation. Of the 41 patients internalized, 20 patients chose conventional programming using an implanted pulse generator to drive four electrodes, while 21 patients chose a tripole stimulation system, which used radiofrequency power and signal transmission and an implanted dual-channel receiver to drive three electrodes using simultaneous pulses of independently variable amplitude. On average, the visual analog scale scores dropped more for patients with TTS systems (32%) than for conventional polarity systems (16%). Conventional polarity systems were using higher frequencies on average, while usage range was similar. Most impressive was the well-controlled "steering" of the paresthesias according to the dermatomal topography of the dorsal columns when using the TTS-balanced pulse driver. The most common complication was lead migration. While the transverse stimulation system produced acceptable outcomes for overall pain relief, an analysis of individual pain patterns suggests that it behaves like spinal cord stimulation in general with the best control of extremity neuropathic pain. This transverse tripole lead and driving system introduced

High dose rate (HDR) and low dose rate (LDR) interstitial irradiation (IRT) of the rat spinal cord

International Nuclear Information System (INIS)

Pop, Lucas A.M.; Plas, Mirjam van der; Skwarchuk, Mark W.; Hanssen, Alex E.J.; Kogel, Albert J. van der

1997-01-01

Purpose: To describe a newly developed technique to study radiation tolerance of rat spinal cord to continuous interstitial irradiation (IRT) at different dose rates. Material and methods: Two parallel catheters are inserted just laterally on each side of the vertebral bodies from the level of Th 10 to L 4 . These catheters are afterloaded with two 192 Ir wires of 4 cm length each (activity 1-2.3 mCi/cm) for the low dose rate (LDR) IRT or connected to the HDR micro-Selectron for the high dose rate (HDR) IRT. Spinal cord target volume is located at the level of Th 12 -L 2 . Due to the rapid dose fall-off around the implanted sources, a dose inhomogeneity across the spinal cord thickness is obtained in the dorso-ventral direction. Using the 100% reference dose (rate) at the ventral side of the spinal cord to prescribe the dose, experiments have been carried out to obtain complete dose response curves at average dose rates of 0.49, 0.96 and 120 Gy/h. Paralysis of the hind-legs after 5-6 months and histopathological examination of the spinal cord of each irradiated rat are used as experimental endpoints. Results: The histopathological damage seen after irradiation is clearly reflected the inhomogeneous dose distribution around the implanted catheters, with the damage predominantly located in the dorsal tract of the cord or dorsal roots. With each reduction in average dose rate, spinal cord radiation tolerance is significantly increased. When the dose is prescribed at the 100% reference dose rate, the ED 50 (induction of paresis in 50% of the animals) for the HDR-IRT is 17.3 Gy. If the average dose rate is reduced from 120 Gy/h to 0.96 or 0.49 Gy/h, a 2.9- or 4.7-fold increase in the ED 50 values to 50.3 Gy and 80.9 Gy is observed; for the dose prescribed at the 150% reference dose rate (dorsal side of cord) ED 50 values are 26.0, 75.5 and 121.4 Gy, respectively. Using different types of analysis and in dependence of the dose prescription and reference dose rate, the �

Diaphragmatic reinnervation in ventilator-dependent patients with cervical spinal cord injury and concomitant phrenic nerve lesions using simultaneous nerve transfers and implantable neurostimulators.

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Kaufman, Matthew R; Elkwood, Andrew I; Aboharb, Farid; Cece, John; Brown, David; Rezzadeh, Kameron; Jarrahy, Reza

2015-06-01

Patients who are ventilator dependent as a result of combined cervical spinal cord injury and phrenic nerve lesions are generally considered to be unsuitable candidates for diaphragmatic pacing due to loss of phrenic nerve integrity and denervation of the diaphragm. There is limited data regarding efficacy of simultaneous nerve transfers and diaphragmatic pacemakers in the treatment of this patient population. A retrospective review was conducted of 14 consecutive patients with combined lesions of the cervical spinal cord and phrenic nerves, and with complete ventilator dependence, who were treated with simultaneous microsurgical nerve transfer and implantation of diaphragmatic pacemakers. Parameters of interest included time to recovery of diaphragm electromyographic activity, average time pacing without the ventilator, and percent reduction in ventilator dependence. Recovery of diaphragm electromyographic activity was demonstrated in 13 of 14 (93%) patients. Eight of these 13 (62%) patients achieved sustainable periods (> 1 h/d) of ventilator weaning (mean = 10 h/d [n = 8]). Two patients recovered voluntary control of diaphragmatic activity and regained the capacity for spontaneous respiration. The one patient who did not exhibit diaphragmatic reinnervation remains within 12 months of initial treatment. Surgical intervention resulted in a 25% reduction (p nerve transfers and pacemaker implantation can result in reinnervation of the diaphragm and lead to successful ventilator weaning. Our favorable outcomes support consideration of this surgical method for appropriate patients who would otherwise have no alternative therapy to achieve sustained periods of ventilator independence. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Banking on cord blood stem cells.

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Sullivan, Michael J

2008-07-01

Umbilical cord blood gifted to non-profit public cord blood banks is now routinely used as an alternative source of haematopoietic stem cells for allogeneic transplantation for children and adults with cancer, bone marrow failure syndromes, haemoglobinopathies and many genetic metabolic disorders. Because of the success and outcomes of public cord banking, many companies now provide private cord banking services. However, in the absence of any published transplant evidence to support autologous and non-directed family banking, commercial cord banks currently offer a superfluous service.

Robust optical fiber patch-cords for in vivo optogenetic experiments in rats.

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Trujillo-Pisanty, Ivan; Sanio, Christian; Chaudhri, Nadia; Shizgal, Peter

2015-01-01

In vivo optogenetic experiments commonly employ long lengths of optical fiber to connect the light source (commonly a laser) to the optical fiber implants in the brain. Commercially available patch cords are expensive and break easily. Researchers have developed methods to build these cables in house for in vivo experiments with rodents [1-4]. However, the half-life of those patch cords is greatly reduced when they are used with behaving rats, which are strong enough to break the delicate cable tip and to bite through the optical fiber and furcation tubing. Based on [3] we have strengthened the patch-cord tip that connects to the optical implant, and we have incorporated multiple layers of shielding to produce more robust and resistant cladding. Here, we illustrate how to build these patch cords with FC or M3 connectors. However, the design can be adapted for use with other common optical-fiber connectors. We have saved time and money by using this design in our optical self-stimulation experiments with rats, which are commonly several months long and last four to eleven hours per session. The main advantages are: •Long half-life.•Resistant to moderate rodent bites.•Suitable for long in vivo optogenetic experiments with large rodents.

Treatment of Neuropathic Pain and Functional Limitations Associated With Multiple Sclerosis Using an MRI-Compatible Spinal Cord Stimulator: A Case Report With Two Year Follow-Up and Literature Review.

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Provenzano, David A; Williams, Joseph R; Jarzabek, Gaye; DeRiggi, Leonard A; Scott, Thomas F

2016-06-01

To report a case with two years follow-up of neuropathic pain and functional limitations associated with multiple sclerosis (MS) effectively treated with an MRI conditional spinal cord stimulator (SCS) system that allowed for spinal imaging. To present a comprehensive literature review of spinal cord stimulator utilization in the treatment of multiple sclerosis. Case report and literature review. Treatment was a spinal cord stimulation implant after successful trial. Pain scores, medication utilization, and functional outcomes were reviewed. Pre- and post-SCS implant MRI spine images were obtained. At 24 months follow-up, the patient has had a 77% reduction in pain and a 99% reduction in opioid use. Furthermore, he had improvement in reported tactile sensation, spasticity levels, and ambulation. Post-SCS implant, MRI images at 18 months follow-up provided the ability to review the spinal cord with minimal artifact. No new MS documented plaques occurred during this time period. A literature review demonstrated 33 published reports including a total of 496 trialed and 744 implanted patients. Only 3 of the reports occurred after the year 2000. We report the successful treatment of MS-associated pain and functional limitations with an MRI conditional spinal cord stimulator system. The ability to obtain post-implant MRI imaging of not only the brain but also the spinal cord in MS patients allows for the continued need to document and follow disease progression, especially with the advancements in pharmacological therapy. © 2016 International Neuromodulation Society.

Current control for magnetized plasma in direct-current plasma-immersion ion implantation

International Nuclear Information System (INIS)

Tang Deli; Chu, Paul K.

2003-01-01

A method to control the ion current in direct-current plasma-immersion ion implantation (PIII) is reported for low-pressure magnetized inductively coupled plasma. The ion current can be conveniently adjusted by applying bias voltage to the conducting grid that separates plasma formation and implantation (ion acceleration) zones without the need to alter the rf input power, gas flux, or other operating conditions. The ion current that diminishes with an increase in grid bias in magnetized plasmas can be varied from 48 to 1 mA by increasing the grid voltage from 0 to 70 V at -50 kV sample bias and 0.5 mTorr hydrogen pressure. High implantation voltage and monoenergetic immersion implantation can now be achieved by controlling the ion current without varying the macroscopic plasma parameters. The experimental results and interpretation of the effects are presented in this letter. This technique is very attractive for PIII of planar samples that require on-the-fly adjustment of the implantation current at high implantation voltage but low substrate temperature. In some applications such as hydrogen PIII-ion cut, it may obviate the need for complicated sample cooling devices that must work at high voltage

Vocal cord dysfunction in children.

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Noyes, Blakeslee E; Kemp, James S

2007-06-01

Vocal cord dysfunction is characterised by paradoxical vocal cord adduction that occurs during inspiration, resulting in symptoms of dyspnoea, wheeze, chest or throat tightness and cough. Although the condition is well described in children and adults, confusion with asthma often triggers the use of an aggressive treatment regimen directed against asthma. The laryngoscopic demonstration of vocal cord adduction during inspiration has been considered the gold standard for the diagnosis of vocal cord dysfunction, but historical factors and pulmonary function findings may provide adequate clues to the correct diagnosis. Speech therapy, and in some cases psychological counselling, is often beneficial in this disorder. The natural course and prognosis of vocal cord dysfunction are still not well described in adults or children.

A Direct Comparison between Norepinephrine and Phenylephrine for Augmenting Spinal Cord Perfusion in a Porcine Model of Spinal Cord Injury.

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Streijger, Femke; So, Kitty; Manouchehri, Neda; Gheorghe, Ana; Okon, Elena B; Chan, Ryan M; Ng, Benjamin; Shortt, Katelyn; Sekhon, Mypinder S; Griesdale, Donald E; Kwon, Brian K

2018-03-28

Current clinical guidelines recommend elevating the mean arterial blood pressure (MAP) to increase spinal cord perfusion in patients with acute spinal cord injury (SCI). This is typically achieved with vasopressors such as norepinephrine (NE) and phenylephrine (PE). These drugs differ in their pharmacological properties and potentially have different effects on spinal cord blood flow (SCBF), oxygenation (PO 2 ), and downstream metabolism after injury. Using a porcine model of thoracic SCI, we evaluated how these vasopressors influenced intraparenchymal SCBF, PO 2 , hydrostatic pressure, and metabolism within the spinal cord adjacent to the injury site. Yorkshire pigs underwent a contusion/compression SCI at T10 and were randomized to receive either NE or PE for MAP elevation of 20 mm Hg, or no MAP augmentation. Prior to injury, a combined SCBF/PO 2 sensor, a pressure sensor, and a microdialysis probe were inserted into the spinal cord adjacent to T10 at two locations: a "proximal" site and a "distal" site, 2 mm and 22 mm from the SCI, respectively. At the proximal site, NE and PE resulted in little improvement in SCBF during cord compression. Following decompression, NE resulted in increased SCBF and PO 2 , whereas decreased levels were observed for PE. However, both NE and PE were associated with a gradual decrease in the lactate to pyruvate (L/P) ratio after decompression. PE was associated with greater hemorrhage through the injury site than that in control animals. Combined, our results suggest that NE promotes better restoration of blood flow and oxygenation than PE in the traumatically injured spinal cord, thus providing a physiological rationale for selecting NE over PE in the hemodynamic management of acute SCI.

Cervical Cord-Canal Mismatch: A New Method for Identifying Predisposition to Spinal Cord Injury.

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Nouri, Aria; Montejo, Julio; Sun, Xin; Virojanapa, Justin; Kolb, Luis E; Abbed, Khalid M; Cheng, Joseph S

2017-12-01

The risk for spinal cord injuries (SCIs) ranging from devastating traumatic injuries, compression because of degenerative pathology, and neurapraxia is increased in patients with congenital spinal stenosis. Classical diagnostic criteria include an absolute anteroposterior diameter of spinal cord, which varies across patients, independent of canal size. Recent large magnetic resonance imaging studies of population cohorts have allowed newer methods to emerge that account for both cord and canal size by measuring a spinal cord occupation ratio (SCOR). A SCOR defined as ≥70% on midsagittal imaging or ≥80% on axial imaging appears to be an effective method of identifying cord-canal mismatch, but requires further validation. Cord-canal size mismatch predisposes patients to SCI because of 1) less space within the canal lowering the amount of degenerative changes needed for cord compression, and 2) less cerebrospinal fluid surrounding the spinal cord decreasing the ability to absorb kinetic forces directed at the spine. Patients with cord-canal mismatch have been reported to be at a substantially higher risk of traumatic SCI, and present with degenerative cervical myelopathy at a younger age than patients without cord-canal mismatch. However, neurologic outcome after SCI has occurred does not appear to be different in patients with or without a cord-canal mismatch. Recognition that canal and cord size are both factors which predispose to SCI supports that cord-canal size mismatch rather than a narrow cervical canal in isolation should be viewed as the underlying mechanism predisposing to SCI. Copyright © 2017. Published by Elsevier Inc.

Direction-dependent RBS channelling studies in ion implanted LiNbO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Wendler, E., E-mail: elke.wendler@uni-jena.de; Becker, G.; Rensberg, J.; Schmidt, E.; Wolf, S.; Wesch, W.

2016-07-15

Damage formation in ion implanted LiNbO{sub 3} was studied by Rutherford backscattering spectrometry (RBS) along various directions of the LiNbO{sub 3} crystal. From the results obtained it can be unambiguously concluded that Nb atoms being displaced during ion implantation preferably occupy the free octahedron sites of the LiNbO{sub 3} lattice structure and most likely also form Nb{sub Li} antisite defects.

Post-test probability for neonatal hyperbilirubinemia based on umbilical cord blood bilirubin, direct antiglobulin test, and ABO compatibility results.

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Peeters, Bart; Geerts, Inge; Van Mullem, Mia; Micalessi, Isabel; Saegeman, Veroniek; Moerman, Jan

2016-05-01

Many hospitals opt for early postnatal discharge of newborns with a potential risk of readmission for neonatal hyperbilirubinemia. Assays/algorithms with the possibility to improve prediction of significant neonatal hyperbilirubinemia are needed to optimize screening protocols and safe discharge of neonates. This study investigated the predictive value of umbilical cord blood (UCB) testing for significant hyperbilirubinemia. Neonatal UCB bilirubin, UCB direct antiglobulin test (DAT), and blood group were determined, as well as the maternal blood group and the red blood cell antibody status. Moreover, in newborns with clinically apparent jaundice after visual assessment, plasma total bilirubin (TB) was measured. Clinical factors positively associated with UCB bilirubin were ABO incompatibility, positive DAT, presence of maternal red cell antibodies, alarming visual assessment and significant hyperbilirubinemia in the first 6 days of life. UCB bilirubin performed clinically well with an area under the receiver-operating characteristic curve (AUC) of 0.82 (95 % CI 0.80-0.84). The combined UCB bilirubin, DAT, and blood group analysis outperformed results of these parameters considered separately to detect significant hyperbilirubinemia and correlated exponentially with hyperbilirubinemia post-test probability. Post-test probabilities for neonatal hyperbilirubinemia can be calculated using exponential functions defined by UCB bilirubin, DAT, and ABO compatibility results. • The diagnostic value of the triad umbilical cord blood bilirubin measurement, direct antiglobulin testing and blood group analysis for neonatal hyperbilirubinemia remains unclear in literature. • Currently no guideline recommends screening for hyperbilirubinemia using umbilical cord blood. What is New: • Post-test probability for hyperbilirubinemia correlated exponentially with umbilical cord blood bilirubin in different risk groups defined by direct antiglobulin test and ABO blood group

Direct transcatheter aortic valve implantation with self-expandable bioprosthesis: Feasibility and safety

Energy Technology Data Exchange (ETDEWEB)

Fiorina, Claudia, E-mail: clafiorina@yahoo.it [Cardiac Catheterization Laboratory, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Maffeo, Diego; Curello, Salvatore [Cardiac Catheterization Laboratory, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Lipartiti, Felicia [Division of Cardiology, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Chizzola, Giuliano [Cardiac Catheterization Laboratory, Cardiothoracic Department, Spedali Civili, Brescia (Italy); D' Aloia, Antonio [Division of Cardiology, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Adamo, Marianna [Cardiac Catheterization Laboratory, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Mastropierro, Rosy [Division of Cardiothoracic Anestesiology, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Gavazzi, Emanuele [Department of Radiology, University of Brescia, Spedali Civili, Brescia (Italy); Ciccarese, Camilla; Chiari, Ermanna [Division of Cardiology, Cardiothoracic Department, Spedali Civili, Brescia (Italy); Ettori, Federica [Cardiac Catheterization Laboratory, Cardiothoracic Department, Spedali Civili, Brescia (Italy)

2014-06-15

Background: Balloon valvuloplasty has been considered a mandatory step of the transcatheter aortic valve implantation (TAVI), although it is not without risk. The aim of this work was to evaluate the feasibility and safety of TAVI performed without pre-dilation (direct TAVI) of the stenosed aortic valve. Material and Methods: Between June 2012 and June 2013, 55 consecutive TAVI performed without pre-dilation at our institution using the self-expandable CoreValve prosthesis (Medtronic, Minneapolis, MN) were analyzed and compared with 45 pre-dilated TAVI performed the previous year. Inclusion criteria were a symptomatic and severe aortic stenosis. Exclusion criteria were defined as presence of pure aortic regurgitation, degenerated surgical bioprosthesis or bicuspid aortic valve and prior procedure of balloon aortic valvuloplasty performed as a bridge to TAVI. Results: High-burden calcification in the device landing zone, assessed by CT scan, was found in most of the patients. The valve size implanted was similar in both groups. Device success was higher in direct TAVI (85% vs. 64%, p = 0.014), mostly driven by a significant lower incidence of paravalvular leak (PVL ≥2; 9% vs. 33%, p = 0.02). Safety combined end point at 30 days was similar in both groups. Conclusion: Compared to TAVI with pre-dilation, direct TAVI is feasible regardless of the presence of bulky calcified aortic valve and the valve size implanted. Device success was higher in direct TAVI, mostly driven by a lower incidence of paravalvular leak. Safety at 30 days was similar in two groups.

Spinal cord stimulation paresthesia and activity of primary afferents.

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North, Richard B; Streelman, Karen; Rowland, Lance; Foreman, P Jay

2012-10-01

A patient with failed back surgery syndrome reported paresthesia in his hands and arms during a spinal cord stimulation (SCS) screening trial with a low thoracic electrode. The patient's severe thoracic stenosis necessitated general anesthesia for simultaneous decompressive laminectomy and SCS implantation for chronic use. Use of general anesthesia gave the authors the opportunity to characterize the patient's unusual distribution of paresthesia. During SCS implantation, they recorded SCS-evoked antidromic potentials at physiologically relevant amplitudes in the legs to guide electrode placement and in the arms as controls. Stimulation of the dorsal columns at T-8 evoked potentials in the legs (common peroneal nerves) and at similar thresholds, consistent with the sensation of paresthesia in the arms, in the right ulnar nerve. The authors' electrophysiological observations support observations by neuroanatomical specialists that primary afferents can descend several (in this case, at least 8) vertebral segments in the spinal cord before synapsing or ascending. This report thus confirms a physiological basis for unusual paresthesia distribution associated with thoracic SCS.

Direct Metal Laser Sintering Titanium Dental Implants: A Review of the Current Literature

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Mangano, F.; Chambrone, L.; van Noort, R.; Miller, C.; Hatton, P.; Mangano, C.

2014-01-01

Statement of Problem. Direct metal laser sintering (DMLS) is a technology that allows fabrication of complex-shaped objects from powder-based materials, according to a three-dimensional (3D) computer model. With DMLS, it is possible to fabricate titanium dental implants with an inherently porous surface, a key property required of implantation devices. Objective. The aim of this review was to evaluate the evidence for the reliability of DMLS titanium dental implants and their clinical and histologic/histomorphometric outcomes, as well as their mechanical properties. Materials and Methods. Electronic database searches were performed. Inclusion criteria were clinical and radiographic studies, histologic/histomorphometric studies in humans and animals, mechanical evaluations, and in vitro cell culture studies on DMLS titanium implants. Meta-analysis could be performed only for randomized controlled trials (RCTs); to evaluate the methodological quality of observational human studies, the Newcastle-Ottawa scale (NOS) was used. Results. Twenty-seven studies were included in this review. No RCTs were found, and meta-analysis could not be performed. The outcomes of observational human studies were assessed using the NOS: these studies showed medium methodological quality. Conclusions. Several studies have demonstrated the potential for the use of DMLS titanium implants. However, further studies that demonstrate the benefits of DMLS implants over conventional implants are needed. PMID:25525434

Direct metal laser sintering titanium dental implants: a review of the current literature.

Science.gov (United States)

Mangano, F; Chambrone, L; van Noort, R; Miller, C; Hatton, P; Mangano, C

2014-01-01

Statement of Problem. Direct metal laser sintering (DMLS) is a technology that allows fabrication of complex-shaped objects from powder-based materials, according to a three-dimensional (3D) computer model. With DMLS, it is possible to fabricate titanium dental implants with an inherently porous surface, a key property required of implantation devices. Objective. The aim of this review was to evaluate the evidence for the reliability of DMLS titanium dental implants and their clinical and histologic/histomorphometric outcomes, as well as their mechanical properties. Materials and Methods. Electronic database searches were performed. Inclusion criteria were clinical and radiographic studies, histologic/histomorphometric studies in humans and animals, mechanical evaluations, and in vitro cell culture studies on DMLS titanium implants. Meta-analysis could be performed only for randomized controlled trials (RCTs); to evaluate the methodological quality of observational human studies, the Newcastle-Ottawa scale (NOS) was used. Results. Twenty-seven studies were included in this review. No RCTs were found, and meta-analysis could not be performed. The outcomes of observational human studies were assessed using the NOS: these studies showed medium methodological quality. Conclusions. Several studies have demonstrated the potential for the use of DMLS titanium implants. However, further studies that demonstrate the benefits of DMLS implants over conventional implants are needed.

Direct Metal Laser Sintering Titanium Dental Implants: A Review of the Current Literature

Directory of Open Access Journals (Sweden)

F. Mangano

2014-01-01

Full Text Available Statement of Problem. Direct metal laser sintering (DMLS is a technology that allows fabrication of complex-shaped objects from powder-based materials, according to a three-dimensional (3D computer model. With DMLS, it is possible to fabricate titanium dental implants with an inherently porous surface, a key property required of implantation devices. Objective. The aim of this review was to evaluate the evidence for the reliability of DMLS titanium dental implants and their clinical and histologic/histomorphometric outcomes, as well as their mechanical properties. Materials and Methods. Electronic database searches were performed. Inclusion criteria were clinical and radiographic studies, histologic/histomorphometric studies in humans and animals, mechanical evaluations, and in vitro cell culture studies on DMLS titanium implants. Meta-analysis could be performed only for randomized controlled trials (RCTs; to evaluate the methodological quality of observational human studies, the Newcastle-Ottawa scale (NOS was used. Results. Twenty-seven studies were included in this review. No RCTs were found, and meta-analysis could not be performed. The outcomes of observational human studies were assessed using the NOS: these studies showed medium methodological quality. Conclusions. Several studies have demonstrated the potential for the use of DMLS titanium implants. However, further studies that demonstrate the benefits of DMLS implants over conventional implants are needed.

Diaphragmatic pacing stimulation in spinal cord injury: anesthetic and perioperative management

Directory of Open Access Journals (Sweden)

Miguel L. Tedde

2012-11-01

Full Text Available OBJECTIVE: The standard therapy for patients with high-level spinal cord injury is long-term mechanical ventilation through a tracheostomy. However, in some cases, this approach results in death or disability. The aim of this study is to highlight the anesthetics and perioperative aspects of patients undergoing insertion of a diaphragmatic pacemaker. METHODS: Five patients with quadriplegia following high cervical traumatic spinal cord injury and ventilator-dependent chronic respiratory failure were implanted with a laparoscopic diaphragmatic pacemaker after preoperative assessments of their phrenic nerve function and diaphragm contractility through transcutaneous nerve stimulation. ClinicalTrials.gov: NCT01385384. RESULTS: The diaphragmatic pacemaker placement was successful in all of the patients. Two patients presented with capnothorax during the perioperative period, which resolved without consequences. After six months, three patients achieved continuous use of the diaphragm pacing system, and one patient could be removed from mechanical ventilation for more than 4 hours per day. CONCLUSIONS: The implantation of a diaphragmatic phrenic system is a new and safe technique with potential to improve the quality of life of patients who are dependent on mechanical ventilation because of spinal cord injuries. Appropriate indication and adequate perioperative care are fundamental to achieving better results.

Spinal cord injury arising in anaesthesia practice.

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Hewson, D W; Bedforth, N M; Hardman, J G

2018-01-01

Spinal cord injury arising during anaesthetic practice is a rare event, but one that carries a significant burden in terms of morbidity and mortality. In this article, we will review the pathophysiology of spinal cord injury. We will then discuss injuries relating to patient position, spinal cord hypoperfusion and neuraxial techniques. The most serious causes of spinal cord injury - vertebral canal haematoma, spinal epidural abscess, meningitis and adhesive arachnoiditis - will be discussed in turn. For each condition, we draw attention to practical, evidence-based measures clinicians can undertake to reduce their incidence, or mitigate their severity. Finally, we will discuss transient neurological symptoms. Some cases of spinal cord injury during anaesthesia can be ascribed to anaesthesia itself, arising as a direct consequence of its conduct. The injury to a spinal nerve root by inaccurate and/or incautious needling during spinal anaesthesia is an obvious example. But in many cases, spinal cord injury during anaesthesia is not caused by, related to, or even associated with, the conduct of the anaesthetic. Surgical factors, whether direct (e.g. spinal nerve root damage due to incorrect pedicle screw placement) or indirect (e.g. cord ischaemia following aortic surgery) are responsible for a significant proportion of spinal cord injuries that occur concurrently with the delivery of regional or general anaesthesia. © 2018 The Association of Anaesthetists of Great Britain and Ireland.

Structural and Functional Substitution of Deleted Primary Sensory Neurons by New Growth from Intrinsic Spinal Cord Nerve Cells: An Alternative Concept in Reconstruction of Spinal Cord Circuits

Directory of Open Access Journals (Sweden)

Nicholas D. James

2017-07-01

Full Text Available In a recent clinical report, return of the tendon stretch reflex was demonstrated after spinal cord surgery in a case of total traumatic brachial plexus avulsion injury. Peripheral nerve grafts had been implanted into the spinal cord to reconnect to the peripheral nerves for motor and sensory function. The dorsal root ganglia (DRG containing the primary sensory nerve cells had been surgically removed in order for secondary or spinal cord sensory neurons to extend into the periphery and replace the deleted DRG neurons. The present experimental study uses a rat injury model first to corroborate the clinical finding of a re-established spinal reflex arch, and second, to elucidate some of the potential mechanisms underlying these findings by means of morphological, immunohistochemical, and electrophysiological assessments. Our findings indicate that, after spinal cord surgery, the central nervous system sensory system could replace the traumatically detached original peripheral sensory connections through new neurite growth from dendrites.

Real-time direct measurement of spinal cord blood flow at the site of compression: relationship between blood flow recovery and motor deficiency in spinal cord injury.

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Hamamoto, Yuichiro; Ogata, Tadanori; Morino, Tadao; Hino, Masayuki; Yamamoto, Haruyasu

2007-08-15

An in vivo study to measure rat spinal cord blood flow in real-time at the site of compression using a newly developed device. To evaluate the change in thoracic spinal cord blood flow by compression force and to clarify the association between blood flow recovery and motor deficiency after a spinal cord compression injury. Until now, no real-time measurement of spinal cord blood flow at the site of compression has been conducted. In addition, it has not been clearly determined whether blood flow recovery is related to motor function after a spinal cord injury. Our blood flow measurement system was a combination of a noncontact type laser Doppler system and a spinal cord compression device. The rat thoracic spinal cord was exposed at the 11th vertebra and spinal cord blood flow at the site of compression was continuously measured before, during, and after the compression. The functioning of the animal's hind-limbs was evaluated by the Basso, Beattie and Bresnahan scoring scale and the frequency of voluntary standing. Histologic changes such as permeability of blood-spinal cord barrier, microglia proliferation, and apoptotic cell death were examined in compressed spinal cord tissue. The spinal blood flow decreased on each increase in the compression force. After applying a 5-g weight, the blood flow decreased to compression), while no significant difference was observed between the 20-minute ischemia group and the sham group. In the 20-minute ischemia group, the rats whose spinal cord blood flow recovery was incomplete showed significant motor function loss compared with rats that completely recovered blood flow. Extensive breakdown of blood-spinal cord barrier integrity and the following microglia proliferation and apoptotic cell death were detected in the 40-minute complete ischemia group. Duration of ischemia/compression and blood flow recovery of the spinal cord are important factors in the recovery of motor function after a spinal cord injury.

Is early cord clamping, delayed cord clamping or cord milking best?

Science.gov (United States)

Vatansever, Binay; Demirel, Gamze; Ciler Eren, Elif; Erel, Ozcan; Neselioglu, Salim; Karavar, Hande Nur; Gundogdu, Semra; Ulfer, Gozde; Bahadir, Selcen; Tastekin, Ayhan

2018-04-01

To compare the antioxidant status of three cord clamping procedures (early clamping, delayed clamping and milking) by analyzing the thiol-disulfide balance. This randomized controlled study enrolled 189 term infants who were divided into three groups according to the cord clamping procedure: early clamping, delayed clamping and milking. Blood samples were collected from the umbilical arteries immediately after clamping, and the thiol/disulfide homeostasis was analyzed. The native and total thiol levels were significantly (p total thiol ratio was significantly (p = .026) lower in the delayed cord clamping and milking groups compared with the early clamping groups. Early cord clamping causes the production of more disulfide bonds and lower thiol levels, indicating that oxidation reactions are increased in the early cord clamping procedure compared with the delayed cord clamping and milking procedures. The oxidant capacity is greater with early cord clamping than with delayed clamping or cord milking. Delayed cord clamping or milking are beneficial in neonatal care, and we suggest that they be performed routinely in all deliveries.

The effects of compound danshen dripping pills and human umbilical cord blood mononuclear cell transplant after acute myocardial infarction.

Science.gov (United States)

Jun, Yi; Chunju, Yuan; Qi, Ai; Liuxia, Deng; Guolong, Yu

2014-04-01

The low frequency of survival of stem cells implanted in the myocardium after acute myocardial infarction may be caused by inflammation and oxidative stress in the myocardial microenvironment. We evaluated the effects of a traditional Chinese medicine, Compound Danshen Dripping Pills, on the cardiac microenvironment and cardiac function when used alone or in combination with human umbilical cord blood mononuclear cell transplant after acute myocardial infarction. After surgically induced acute myocardial infarction, rabbits were treated with Compound Danshen Dripping Pills alone or in combination with human umbilical cord blood mononuclear cell transplant. Evaluation included histology, measurement of left ventricular ejection fraction and fractional shortening, leukocyte count, count of green fluorescent protein positive cells, superoxide dismutase activity, and malondialdehyde content. Combination treatment with Compound Danshen Dripping Pills and human umbilical cord blood mononuclear cell transplant significantly increased the survival of implanted cells, inhibited cardiac cell apoptosis, decreased oxidative stress, decreased the inflammatory response, and improved cardiac function. Rabbits treated with either Compound Danshen Dripping Pills or human umbilical cord blood mononuclear cells alone had improvement in these effects compared with untreated control rabbits. Combination therapy with Compound Danshen Dripping Pills and human umbilical cord blood mononuclear cells may improve cardiac function and morphology after acute myocardial infarction.

Transvertebral direct current stimulation paired with locomotor training in chronic spinal cord injury: A case study.

Science.gov (United States)

Powell, Elizabeth Salmon; Carrico, Cheryl; Raithatha, Ravi; Salyers, Emily; Ward, Andrea; Sawaki, Lumy

2016-01-01

This double-blind, sham-controlled, crossover case study combined transvertebral direct current stimulation (tvDCS) and locomotor training on a robot-assisted gait orthosis (LT-RGO). Determine whether cathodal tvDCS paired with LT-RGO leads to greater changes in function and neuroplasticity than sham tvDCS paired with LT-RGO. University of Kentucky (UK) HealthCare Stroke and Spinal Cord Neurorehabilitation Research at HealthSouth Cardinal Hill Hospital. A single subject with motor incomplete spinal cord injury (SCI) participated in 24 sessions of sham tvDCS paired with LT-RGO before crossover to 24 sessions of cathodal tvDCS paired with LT-RGO. Functional outcomes were measured with 10 Meter Walk Test (10MWT), 6 Minute Walk Test (6MWT), Spinal Cord Independence Measure-III (SCIM-III) mobility component, lower extremity manual muscle test (MMT), and Berg Balance Scale (BBS). Corticospinal changes were assessed using transcranial magnetic stimulation. Improvement in 10MWT speed, SCIM-III mobility component, and BBS occurred with both conditions. 6MWT worsened after sham tvDCS and improved after cathodal tvDCS. MMT scores for both lower extremities improved following sham tvDCS but decreased following cathodal tvDCS. Corticospinal excitability increased following cathodal tvDCS but not sham tvDCS. These results suggest that combining cathodal tvDCS and LT-RGO may improve functional outcomes, increase corticospinal excitability, and possibly decrease spasticity. Randomized controlled trials are needed to confirm these conclusions. This publication was supported by the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health, through Grant UL1TR000117, and the HealthSouth Cardinal Hill Stroke and Spinal Cord Endowment (1215375670).

Direct synthesis of ultrathin SOI structure by extremely low-energy oxygen implantation

Energy Technology Data Exchange (ETDEWEB)

Hoshino, Yasushi, E-mail: yhoshino@kanagawa-u.ac.jp; Yachida, Gosuke; Inoue, Kodai; Toyohara, Taiga; Nakata, Jyoji [Department of mathematics and physics, Kanagawa University, 2946, Tsuchiya, Hiratsuka, Kanagawa 259-1293 (Japan)

2016-06-15

We performed extremely low-energy {sup 16}O{sup +} implantation at 10 keV (R{sub p} ∼ 25 nm) followed by annealing aiming at directly synthesizing an ultrathin Si layer separated by a buried SiO{sub 2} layer in Si(001) substrates, and then investigated feasible condition of recrystallization and stabilization of the superficial Si and the buried oxide layer by significantly low temperature annealing. The elemental compositions were analyzed by Rutherford backscattering (RBS) and secondary ion mass spectroscopy (SIMS). The crystallinity of the superficial Si layer was quantitatively confirmed by ananlyzing RBS-channeling spectra. Cross-sectional morphologies and atomic configurations were observed by transmission electron microscope (TEM). As a result, we succeeded in directly synthesizing an ultrathin single-crystalline silicon layer with ≤20 nm thick separated by a thin buried stoichiometric SiO{sub 2} layer with ≤20 nm thick formed by extremely low-energy {sup 16}O{sup +} implantation followed by surprisingly low temperature annealing at 1050{sup ∘} C.

Development of an in situ polymeric hydrogel implant of ...

African Journals Online (AJOL)

Purpose: To prepare and characterize in situ gel-forming implants of methylprednisolone for the treatment of spinal cord injuries. Methods: In situ hydrogels of methylprednisolone were prepared by dispersing polylactide glycolic acid (PLGA) polymer and methylprednisolone in N-methyl-pyrrolidone solvent, and subsequent ...

Maxillary Overdentures Supported by Four Splinted Direct Metal Laser Sintering Implants: A 3-Year Prospective Clinical Study

Directory of Open Access Journals (Sweden)

Francesco Mangano

2014-01-01

Full Text Available Purpose. Nowadays, the advancements in direct metal laser sintering (DMLS technology allow the fabrication of titanium dental implants. The aim of this study was to evaluate implant survival, complications, and peri-implant marginal bone loss of DMLS implants used to support bar-retained maxillary overdentures. Materials and Methods. Over a 2-year period, 120 implants were placed in the maxilla of 30 patients (18 males, 12 females to support bar-retained maxillary overdentures (ODs. Each OD was supported by 4 implants splinted by a rigid cobalt-chrome bar. At each annual follow-up session, clinical and radiographic parameters were assessed. The outcome measures were implant failure, biological and prosthetic complications, and peri-implant marginal bone loss (distance between the implant shoulder and the first visible bone-to-implant contact, DIB. Results. The 3-year implant survival rate was 97.4% (implant-based and 92.9% (patient-based. Three implants failed. The incidence of biological complication was 3.5% (implant-based and 7.1% (patient-based. The incidence of prosthetic complication was 17.8% (patient-based. No detrimental effects on marginal bone level were evidenced. Conclusions. The use of 4 DMLS titanium implants to support bar-retained maxillary ODs seems to represent a safe and successful procedure. Long-term clinical studies on a larger sample of patients are needed to confirm these results.

Maxillary overdentures supported by four splinted direct metal laser sintering implants: a 3-year prospective clinical study.

Science.gov (United States)

Mangano, Francesco; Luongo, Fabrizia; Shibli, Jamil Awad; Anil, Sukumaran; Mangano, Carlo

2014-01-01

Purpose. Nowadays, the advancements in direct metal laser sintering (DMLS) technology allow the fabrication of titanium dental implants. The aim of this study was to evaluate implant survival, complications, and peri-implant marginal bone loss of DMLS implants used to support bar-retained maxillary overdentures. Materials and Methods. Over a 2-year period, 120 implants were placed in the maxilla of 30 patients (18 males, 12 females) to support bar-retained maxillary overdentures (ODs). Each OD was supported by 4 implants splinted by a rigid cobalt-chrome bar. At each annual follow-up session, clinical and radiographic parameters were assessed. The outcome measures were implant failure, biological and prosthetic complications, and peri-implant marginal bone loss (distance between the implant shoulder and the first visible bone-to-implant contact, DIB). Results. The 3-year implant survival rate was 97.4% (implant-based) and 92.9% (patient-based). Three implants failed. The incidence of biological complication was 3.5% (implant-based) and 7.1% (patient-based). The incidence of prosthetic complication was 17.8% (patient-based). No detrimental effects on marginal bone level were evidenced. Conclusions. The use of 4 DMLS titanium implants to support bar-retained maxillary ODs seems to represent a safe and successful procedure. Long-term clinical studies on a larger sample of patients are needed to confirm these results.

Vocal Cord Paralysis

Science.gov (United States)

... Viral infections. Some viral infections, such as Lyme disease, Epstein-Barr and herpes, can cause inflammation and damage directly to the nerves in the larynx. Neurological conditions. If you have certain ... disease, you may experience vocal cord paralysis. Risk factors ...

Biomimetic hydrogels direct spinal progenitor cell differentiation and promote functional recovery after spinal cord injury

Science.gov (United States)

Geissler, Sydney A.; Sabin, Alexandra L.; Besser, Rachel R.; Gooden, Olivia M.; Shirk, Bryce D.; Nguyen, Quan M.; Khaing, Zin Z.; Schmidt, Christine E.

2018-04-01

Objective. Demyelination that results from disease or traumatic injury, such as spinal cord injury (SCI), can have a devastating effect on neural function and recovery. Many researchers are examining treatments to minimize demyelination by improving oligodendrocyte availability in vivo. Transplantation of stem and oligodendrocyte progenitor cells is a promising option, however, trials are plagued by undirected differentiation. Here we introduce a biomaterial that has been optimized to direct the differentiation of neural progenitor cells (NPCs) toward oligodendrocytes as a cell delivery vehicle after SCI. Approach. A collagen-based hydrogel was modified to mimic the mechanical properties of the neonatal spinal cord, and components present in the developing extracellular matrix were included to provide appropriate chemical cues to the NPCs to direct their differentiation toward oligodendrocytes. The hydrogel with cells was then transplanted into a unilateral cervical contusion model of SCI to examine the functional recovery with this treatment. Six behavioral tests and histological assessment were performed to examine the in vivo response to this treatment. Main results. Our results demonstrate that we can achieve a significant increase in oligodendrocyte differentiation of NPCs compared to standard culture conditions using a three-component biomaterial composed of collagen, hyaluronic acid, and laminin that has mechanical properties matched to those of neonatal neural tissue. Additionally, SCI rats with hydrogel transplants, with and without NPCs, showed functional recovery. Animals transplanted with hydrogels with NPCs showed significantly increased functional recovery over six weeks compared to the media control group. Significance. The three-component hydrogel presented here has the potential to provide cues to direct differentiation in vivo to encourage regeneration of the central nervous system.

Spinal cord stimulation in chronic intractable angina pectoris : A randomized, controlled efficacy study

NARCIS (Netherlands)

Hautvast, RWM; DeJongste, MJL; Staal, MJ; van Gilst, WH; Lie, KI

1998-01-01

Background Spinel cord stimulation is known to be a successful treatment for chronic intractable angina pectoris. its effect may be anti-ischemic. It is uncertain if the clinical effect is partly caused by a placebo effect of surgery For implantation of a stimulator. In this study, clinical efficacy

Transcutaneous spinal direct current stimulation of the lumbar and sacral spinal cord: a modelling study

Science.gov (United States)

Fernandes, Sofia R.; Salvador, Ricardo; Wenger, Cornelia; de Carvalho, Mamede; Miranda, Pedro C.

2018-06-01

Objective. Our aim was to perform a computational study of the electric field (E-field) generated by transcutaneous spinal direct current stimulation (tsDCS) applied over the thoracic, lumbar and sacral spinal cord, in order to assess possible neuromodulatory effects on spinal cord circuitry related with lower limb functions. Approach. A realistic volume conductor model of the human body consisting of 14 tissues was obtained from available databases. Rubber pad electrodes with a metallic connector and a conductive gel layer were modelled. The finite element (FE) method was used to calculate the E-field when a current of 2.5 mA was passed between two electrodes. The main characteristics of the E-field distributions in the spinal grey matter (spinal-GM) and spinal white matter (spinal-WM) were compared for seven montages, with the anode placed either over T10, T8 or L2 spinous processes (s.p.), and the cathode placed over right deltoid (rD), umbilicus (U) and right iliac crest (rIC) areas or T8 s.p. Anisotropic conductivity of spinal-WM and of a group of dorsal muscles near the vertebral column was considered. Main results. The average E-field magnitude was predicted to be above 0.15 V m-1 in spinal cord regions located between the electrodes. L2-T8 and T8-rIC montages resulted in the highest E-field magnitudes in lumbar and sacral spinal segments (>0.30 V m-1). E-field longitudinal component is 3 to 6 times higher than the ventral-dorsal and right-left components in both the spinal-GM and WM. Anatomical features such as CSF narrowing due to vertebrae bony edges or disks intrusions in the spinal canal correlate with local maxima positions. Significance. Computational modelling studies can provide detailed information regarding the electric field in the spinal cord during tsDCS. They are important to guide the design of clinical tsDCS protocols that optimize stimulation of application-specific spinal targets.

Metallic and/or oxygen ion implantation into AlN ceramics as a method of preparation for its direct bonding with copper

International Nuclear Information System (INIS)

Barlak, M.; Borkowska, K.; Olesinska, W.; Kalinski, D.; Piekoszewski, J.; Werner, Z.; Jagielski, J.; Sartowska, B.

2006-01-01

Direct bonding (DB) process is recently getting an increasing interest as a method for producing high quality joints between aluminum nitride (AlN) ceramics and copper. The metallic ions were implanted using an MEVVA type TITAN implanter with unseparated beam. Oxygen ions were implanted using a semi-industrial ion implanter without mass separation equipped with a gaseous ion source. The substrate temperature did not exceed 200 o C. Ions were implanted at two acceleration voltages, i.e. 15 and 70 kV. The fluence range was between 1·E16 and 1·E18 cm -2 . After implantation, some of the samples were characterized by the Rutherford backscattering (RBS) method. In conclusion: (a) The investigations performed in the present work confirm an assumption that ion implantation is a very promising technique as a pretreatment of AlN ceramics for the formation of the joints with copper in direct bonding process. (b) It has been shown that titanium implantation gives the best results in comparison to other metals examined (Fe, Cr, Cu) but also in comparison to double Ti+O and O+Ti implantations

Custom-made, root-analogue direct laser metal forming implant: a case report.

Science.gov (United States)

Mangano, Francesco Guido; Cirotti, Bruno; Sammons, Rachel Lilian; Mangano, Carlo

2012-11-01

In the last few years, the application of digital technology in dentistry has become widespread with the introduction of cone beam computed tomography (CBCT) scan technology, and considerable progress has been made in the development of computer-aided design/ computer-aided manufacturing (CAD/CAM) techniques, including direct laser metal forming (DLMF). DLMF is a technology which allows solids with complex geometry to be produced by annealing metal powder microparticles in a focused laser beam, according to a computer-generated three-dimensional (3D) model. For dental implants, the fabrication process involves the laser-induced fusion of titanium microparticles, in order to build, layer by layer, the desired object. At present, the combined use of CBCT 3D data and CAD/CAM technology makes it possible to manufacture custom-made, root-analogue implants (RAI) with sufficient precision. This report demonstrates the successful clinical use of a custom-made, root-analogue DLMF implant. CBCT images of a non-restorable right maxillary first premolar were acquired and transformed into a 3D model. From this model, a custom-made, root-analogue DLMF implant was fabricated. Immediately after tooth extraction, the RAI with a pre-operatively designed abutment was placed in the extraction socket and restored with a single crown. At the 1-year follow-up examination, the RAI showed a good functional and aesthetic integration. The introduction of DLMF technology signals the start of a new revolutionary era for implant dentistry as its immense potential for producing highly complex macro- and microstructures is receiving vast interest in different medical fields.

Conduction of impulses by axons regenerated in a Schwann cell graft in the transected adult rat thoracic spinal cord.

Science.gov (United States)

Pinzon, A; Calancie, B; Oudega, M; Noga, B R

2001-06-01

Central nervous system axons regenerate into a Schwann cell implant placed in the transected thoracic spinal cord of an adult rat. The present study was designed to test whether these regenerated axons are capable of conducting action potentials. Following the transection and removal of a 4- to 5-mm segment of the thoracic spinal cord (T8-T9), a polymer guidance channel filled with a mixture of adult rat Schwann cells and Matrigel was grafted into a 4- to 5-mm-long gap in the transected thoracic spinal cord. The two cut ends of the spinal cord were eased into the guidance channel openings. Transected control animals received a channel containing Matrigel only. Three months after implantation, electrophysiological studies were performed. Tungsten microelectrodes were used for monopolar stimulation of regenerated axons within the Schwann cell graft. Glass microelectrodes were used to record responses in the spinal cord rostral to the stimulation site. Evoked responses to electrical stimulation of the axon cable were found in two out of nine Schwann cell-grafted animals. These responses had approximate latencies in the range of those of myelinated axons. No responses were seen in any of the Matrigel-grafted animals. Histological analysis revealed that the two cases that showed evoked potentials had the largest number of myelinated axons present in the cable. This study demonstrates that axons regenerating through Schwann cell grafts in the complete transected spinal cord can produce measurable evoked responses following electrical stimulation. Copyright 2001 Wiley-Liss, Inc.

Spinal cord thyrotropin releasing hormone receptors of morphine tolerant-dependent and abstinent rats

Energy Technology Data Exchange (ETDEWEB)

Rahmani, N.H.; Gulati, A.; Bhargava, H.N. (Univ. of Illinois, Chicago (USA))

1990-07-01

The effect of chronic administration of morphine and its withdrawal on the binding of 3H-(3-MeHis2)thyrotropin releasing hormone (3H-MeTRH) to membranes of the spinal cord of the rat was determined. Male Sprague-Dawley rats were implanted with either 6 placebo or 6 morphine pellets (each containing 75-mg morphine base) during a 7-day period. Two sets of animals were used. In one, the pellets were left intact at the time of sacrificing (tolerant-dependent) and in the other, the pellets were removed 16 hours prior to sacrificing (abstinent rats). In placebo-pellet-implanted rats, 3H-MeTRH bound to the spinal cord membranes at a single high affinity binding site with a Bmax of 21.3 +/- 1.6 fmol/mg protein, and an apparent dissociation constant Kd of 4.7 +/- 0.8 nM. In morphine tolerant-dependent or abstinent rats, the binding constants of 3H-MeTRH to spinal cord membranes were unaffected. Previous studies from this laboratory indicate that TRH can inhibit morphine tolerance-dependence and abstinence processes without modifying brain TRH receptors. Together with the present results, it appears that the inhibitory effect of TRH on morphine tolerance-dependence and abstinence is probably not mediated via central TRH receptors but may be due to its interaction with other neurotransmitter systems.

Electroencephalographic evoked pain response is suppressed by spinal cord stimulation in complex regional pain syndrome: a case report.

Science.gov (United States)

Hylands-White, Nicholas; Duarte, Rui V; Beeson, Paul; Mayhew, Stephen D; Raphael, Jon H

2016-12-01

Pain is a subjective response that limits assessment. The purpose of this case report was to explore how the objectivity of the electroencephalographic response to thermal stimuli would be affected by concurrent spinal cord stimulation. A patient had been implanted with a spinal cord stimulator for the management of complex regional pain syndrome of both hands for 8 years. Following ethical approval and written informed consent we induced thermal stimuli using the Medoc PATHWAY Pain & Sensory Evaluation System on the right hand of the patient with the spinal cord stimulator switched off and with the spinal cord stimulator switched on. The patient reported a clinically significant reduction in thermal induced pain using the numerical rating scale (71.4 % reduction) with spinal cord stimulator switched on. Analysis of electroencephalogram recordings indicated the occurrence of contact heat evoked potentials (N2-P2) with spinal cord stimulator off, but not with spinal cord stimulator on. This case report suggests that thermal pain can be reduced in complex regional pain syndrome patients with the use of spinal cord stimulation and offers objective validation of the reported outcomes with this treatment.

Fixed cord

International Nuclear Information System (INIS)

Levy, L.M.; DiChiro, G.; DeSouza, B.; McCullough, D.C.; McVeigh, E.; Hefffez, D.

1989-01-01

Pulsatile longitudinal motion of the spinal cord was examined with MR phase imaging in healthy subjects and in cases involving cord tethering and compression. Asymptomatic patients with a low conus medullaris demonstrated normal cord motion. Clinical improvement was associated with improved cord motion after surgical untethering, provided permanent neurologic damage had not occurred. Decreased and unchanged cord motion was associated with unchanged neurologic deficits. In cases of normal cord motion and possible retethering versus syringomyelia, clinical improvement occurred after shunting only. MR imaging of pulsatile cord motion can be clinically useful in the evaluation of diseases restricting motion of the neuraxis

Histological Evidence of the Osseointegration of Fractured Direct Metal Laser Sintering Implants Retrieved after 5 Years of Function

Directory of Open Access Journals (Sweden)

Francesco Mangano

2017-01-01

Full Text Available Background. Direct metal laser sintering (DMLS is an additive manufacturing technique that allows the fabrication of dental implants layer by layer through the laser fusion of titanium microparticles. The surface of DMLS implants is characterized by a high open porosity with interconnected pores of different sizes; therefore, it has the potential to enhance and accelerate bone healing. To date, however, there are no histologic/histomorphometric studies in the literature evaluating the interface between bone and DMLS implants in the long-term. Purpose. To evaluate the interface between bone and DMLS implants retrieved after 5 years of functional loading. Methods. Two fractured DMLS implants were retrieved from the human jaws, using a 5 mm trephine bur. Both the implants were clinically stable and functioned regularly before fracture. The specimens were processed for histologic/histomorphometric evaluation; the bone-to-implant contact (BIC% was calculated. Results. Compact, mature lamellar bone was found over most of the DMLS implants in close contact with the implant surface; the histomorphometric evaluation showed a mean BIC% of 66.1% (±4.5%. Conclusions. The present histologic/histomorphometric study showed that DMLS implants were well integrated in bone, after 5 years of loading, with the peri-implant bone undergoing continuous remodeling at the interface.

Histological Evidence of the Osseointegration of Fractured Direct Metal Laser Sintering Implants Retrieved after 5 Years of Function

Science.gov (United States)

Piattelli, Adriano

2017-01-01

Background Direct metal laser sintering (DMLS) is an additive manufacturing technique that allows the fabrication of dental implants layer by layer through the laser fusion of titanium microparticles. The surface of DMLS implants is characterized by a high open porosity with interconnected pores of different sizes; therefore, it has the potential to enhance and accelerate bone healing. To date, however, there are no histologic/histomorphometric studies in the literature evaluating the interface between bone and DMLS implants in the long-term. Purpose To evaluate the interface between bone and DMLS implants retrieved after 5 years of functional loading. Methods Two fractured DMLS implants were retrieved from the human jaws, using a 5 mm trephine bur. Both the implants were clinically stable and functioned regularly before fracture. The specimens were processed for histologic/histomorphometric evaluation; the bone-to-implant contact (BIC%) was calculated. Results Compact, mature lamellar bone was found over most of the DMLS implants in close contact with the implant surface; the histomorphometric evaluation showed a mean BIC% of 66.1% (±4.5%). Conclusions The present histologic/histomorphometric study showed that DMLS implants were well integrated in bone, after 5 years of loading, with the peri-implant bone undergoing continuous remodeling at the interface. PMID:28929117

Histological Evidence of the Osseointegration of Fractured Direct Metal Laser Sintering Implants Retrieved after 5 Years of Function.

Science.gov (United States)

Mangano, Francesco; Mangano, Carlo; Piattelli, Adriano; Iezzi, Giovanna

2017-01-01

Direct metal laser sintering (DMLS) is an additive manufacturing technique that allows the fabrication of dental implants layer by layer through the laser fusion of titanium microparticles. The surface of DMLS implants is characterized by a high open porosity with interconnected pores of different sizes; therefore, it has the potential to enhance and accelerate bone healing. To date, however, there are no histologic/histomorphometric studies in the literature evaluating the interface between bone and DMLS implants in the long-term. To evaluate the interface between bone and DMLS implants retrieved after 5 years of functional loading. Two fractured DMLS implants were retrieved from the human jaws, using a 5 mm trephine bur. Both the implants were clinically stable and functioned regularly before fracture. The specimens were processed for histologic/histomorphometric evaluation; the bone-to-implant contact (BIC%) was calculated. Compact, mature lamellar bone was found over most of the DMLS implants in close contact with the implant surface; the histomorphometric evaluation showed a mean BIC% of 66.1% (±4.5%). The present histologic/histomorphometric study showed that DMLS implants were well integrated in bone, after 5 years of loading, with the peri-implant bone undergoing continuous remodeling at the interface.

Cord Blood

Directory of Open Access Journals (Sweden)

Saeed Abroun

2014-05-01

Full Text Available   Stem cells are naïve or master cells. This means they can transform into special 200 cell types as needed by body, and each of these cells has just one function. Stem cells are found in many parts of the human body, although some sources have richer concentrations than others. Some excellent sources of stem cells, such as bone marrow, peripheral blood, cord blood, other tissue stem cells and human embryos, which last one are controversial and their use can be illegal in some countries. Cord blood is a sample of blood taken from a newborn baby's umbilical cord. It is a rich source of stem cells, umbilical cord blood and tissue are collected from material that normally has no use following a child’s birth. Umbilical cord blood and tissue cells are rich sources of stem cells, which have been used in the treatment of over 80 diseases including leukemia, lymphoma and anemia as bone marrow stem cell potency.  The most common disease category has been leukemia. The next largest group is inherited diseases. Patients with lymphoma, myelodysplasia and severe aplastic anemia have also been successfully transplanted with cord blood. Cord blood is obtained by syringing out the placenta through the umbilical cord at the time of childbirth, after the cord has been detached from the newborn. Collecting stem cells from umbilical blood and tissue is ethical, pain-free, safe and simple. When they are needed to treat your child later in life, there will be no rejection or incompatibility issues, as the procedure will be using their own cells. In contrast, stem cells from donors do have these potential problems. By consider about cord blood potency, cord blood banks (familial or public were established. In IRAN, four cord blood banks has activity, Shariati BMT center cord blood bank, Royan familial cord blood banks, Royan public cord blood banks and Iranian Blood Transfusion Organ cord blood banks. Despite 50,000 sample which storage in these banks, but the

Intrathecal baclofen in multiple sclerosis and spinal cord injury: complications and long-term dosage evolution.

Science.gov (United States)

Draulans, Nathalie; Vermeersch, Kristof; Degraeuwe, Bart; Meurrens, Tom; Peers, Koen; Nuttin, Bart; Kiekens, Carlotte

2013-12-01

To investigate the long-term dosage evolution and complication rate of intrathecal baclofen use in multiple sclerosis and spinal cord injury patients, based on a large population with a long follow-up. Retrospective data analysis. Academic hospital. Patients with multiple sclerosis (n = 81) or spinal cord injury (n = 49) having an intrathecal baclofen pump implanted at the University Hospitals Leuven between 1988 and 2009. Medical records review of included patients in August 2010. Complications linked to intrathecal baclofen therapy. Daily baclofen dosage after 3 and 6 months, and yearly thereafter. Data on dosage evolution were analysed using a mixed-effect linear model. In 130 patients with a mean follow-up of 63 months, comprising 797 pump years, 104 complications were recorded. This corresponds to a complication rate of 0.011 per month, equally divided among both groups. Seventy-eight of these complications were catheter related. The mean dosage of baclofen stabilizes two years after implantation at 323 µg/day in the multiple sclerosis population. In spinal cord injury patients the daily dose only stabilizes after five years at a significantly higher dosage (504 µg/day). No significant increase in dosage is seen in the long term. In multiple sclerosis and spinal cord injury patients, intrathecal baclofen therapy has a complication rate of 1% per month. Complications are mainly due to catheter-related problems (74%). The intrathecal baclofen dosage stabilizes in the long term, indicating that long-term tolerance, defined as progressive diminution of the susceptibility to the effects of a drug, is not present.

Cerebral activation is correlated to regional atrophy of the spinal cord and functional motor disability in spinal cord injured individuals

DEFF Research Database (Denmark)

Lundell, Henrik; Christensen, Mark Schram; Barthélemy, Dorothy

2011-01-01

Recovery of function following lesions in the nervous system requires adaptive changes in surviving circuitries. Here we investigate whether changes in cerebral activation are correlated to spinal cord atrophy and recovery of functionality in individuals with incomplete spinal cord injury (SCI). 19...... hand and the functional ability of the SCI participants measured by the clinical motor score on the other. There was no significant correlation between activation in any other cerebral area and the motor score. Activation in ipsilateral somatosensory cortex (S1), M1 and PMC was negatively correlated...... to the width of the spinal cord in the left-right direction, where the corticospinal tract is located, but not in the antero-posterior direction. There was a tendency for a negative correlation between cerebral activation in ipsilateral S1, M1 and PMC and the amplitude of motor evoked potentials...

Extraction of motor activity from the cervical spinal cord of behaving rats

Science.gov (United States)

Prasad, Abhishek; Sahin, Mesut

2006-12-01

Injury at the cervical region of the spinal cord results in the loss of the skeletal muscle control from below the shoulders and hence causes quadriplegia. The brain-computer interface technique is one way of generating a substitute for the lost command signals in these severely paralyzed individuals using the neural signals from the brain. In this study, we are investigating the feasibility of an alternative method where the volitional signals are extracted from the cervical spinal cord above the point of injury. A microelectrode array assembly was implanted chronically at the C5-C6 level of the spinal cord in rats. Neural recordings were made during the face cleaning behavior with forelimbs as this task involves cyclic forelimb movements and does not require any training. The correlation between the volitional motor signals and the elbow movements was studied. Linear regression technique was used to reconstruct the arm movement from the rectified-integrated version of the principal neural components. The results of this study demonstrate the feasibility of extracting the motor signals from the cervical spinal cord and using them for reconstruction of the elbow movements.

Neurogenic bladder in spinal cord injury patients

Directory of Open Access Journals (Sweden)

Al Taweel W

2015-06-01

Full Text Available Waleed Al Taweel, Raouf SeyamDepartment of Urology, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi ArabiaAbstract: Neurogenic bladder dysfunction due to spinal cord injury poses a significant threat to the well-being of patients. Incontinence, renal impairment, urinary tract infection, stones, and poor quality of life are some complications of this condition. The majority of patients will require management to ensure low pressure reservoir function of the bladder, complete emptying, and dryness. Management typically begins with anticholinergic medications and clean intermittent catheterization. Patients who fail this treatment because of inefficacy or intolerability are candidates for a spectrum of more invasive procedures. Endoscopic managements to relieve the bladder outlet resistance include sphincterotomy, botulinum toxin injection, and stent insertion. In contrast, patients with incompetent sphincters are candidates for transobturator tape insertion, sling surgery, or artificial sphincter implantation. Coordinated bladder emptying is possible with neuromodulation in selected patients. Bladder augmentation, usually with an intestinal segment, and urinary diversion are the last resort. Tissue engineering is promising in experimental settings; however, its role in clinical bladder management is still evolving. In this review, we summarize the current literature pertaining to the pathology and management of neurogenic bladder dysfunction in patients with spinal cord injury.Keywords: neurogenic bladder, spinal cord injury, urodynamics, intestine, intermittent catheterization

A questionnaire-based study on patients' experiences with rechargeable implanted programmable generators for spinal cord stimulation to treat chronic lumbar spondylosis pain.

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McAuley, John; Farah, Nima; van Gröningen, Richard; Green, Christopher

2013-01-01

The latest generation of rechargeable implantable programmable generators (IPGs) for spinal cord stimulation may greatly extend IPG lifespan compared with previous nonrechargeable devices. This study explores patients' experiences with these devices. Twenty-five patients attending the Department of Neurostimulation, Royal London Hospital, who were implanted with a rechargeable IPG (SC-1110; Boston Scientific, Minneapolis, MN, USA) to provide pain relief from post-surgical lumbosacral spondylosis were surveyed using a questionnaire. Patients reported a mean (SD) benefit from stimulation of 43.7% (32.6%). On a 1 (worst) to 5 (best) scale, the median score was 5 for ease of recharging. Eight patients who had previously had nonrechargeable IPGs felt the rechargeable system was better (p= 0.0143). A particular issue with nonrechargeable batteries was that, while patients considered 5 years an acceptable interval for battery replacements and the procedure itself not too inconvenient, they felt an acceptable wait for replacement after failure to be only 1 week, much shorter than actual waiting times. Patients found the rechargeable IPG easy to recharge and those who had had previous experience with nonrechargeable devices preferred using the rechargeable device. Its benefits in terms of pain relief fell within the range expected from previous studies using nonrechargeable batteries. The main disadvantage of nonrechargeable devices as reported by the patients in this study was concern over the length of time they would have to wait without pain relief between battery replacements. © 2012 International Neuromodulation Society.

Prophylactic Nipple-Sparing Mastectomy and Direct-to-Implant Reconstruction of the Large and Ptotic Breast

DEFF Research Database (Denmark)

Gunnarsson, Gudjon L; Bille, Camilla; Reitsma, Laurens C

2017-01-01

BACKGROUND: Nipple-sparing mastectomy with simultaneous hammock technique direct-to-implant reconstruction is increasingly offered to patients opting for risk-reducing mastectomy. Despite this promising method, patients with macromastia and ptotic breasts remain a challenging group to treat satis...

[Clinical application of individualized three-dimensional printing implant template in multi-tooth dental implantation].

Science.gov (United States)

Wang, Lie; Chen, Zhi-Yuan; Liu, Rong; Zeng, Hao

2017-08-01

To study the value and satisfaction of three-dimensional printing implant template and conventional implant template in multi-tooth dental implantation. Thirty cases (83 teeth) with missing teeth needing to be implanted were randomly divided into conventional implant template group (CIT group, 15 cases, 42 teeth) and 3D printing implant template group (TDPIT group, 15 cases, 41 teeth). Patients in CIT group were operated by using conventional implant template, while patients in TDPIT group were operated by using three-dimensional printing implant template. The differences of implant neck and tip deviation, implant angle deviation and angle satisfaction between the two groups were compared. The difference of probing depth and bone resorption of implant were compared 1 year after operation between the two groups. The difference of success rate and satisfaction of dental implantation were compared 1 year after operation between the two groups. SPSS19.0 software package was used for statistical analysis. The deviation direction of the neck and the tip in disto-mesial, bucco-palatal, vertical direction and angle of implants in disto-mesial and bucco-palatal direction in TDPIT group were significantly lower than in CIT group (P0.05). The difference of the cumulative success rate in dental implantation at 3 months and 6 months between the two groups were not significant (P>0.05), but the cumulative success rate of TDPIT group was significantly higher than CIT group at 9 months and 1 year (90.48% vs 100%,P=0.043). The patients' satisfaction rate of dental implantation in TDPIT group was significantly higher than in CIT group (86.67% vs 53.33%, P=0.046). Using three-dimensional printing implant template can obtain better accuracy of implant, higher implant success rate and better patients' satisfaction than using conventional implant template. It is suitable for clinical application.

Outcome measures in spinal cord injury: recent assessments and recommendations for future directions

DEFF Research Database (Denmark)

Alexander, M S; Anderson, K D; Biering-Sørensen, Fin

2009-01-01

Study design:Review by the spinal cord outcomes partnership endeavor (SCOPE), which is a broad-based international consortium of scientists and clinical researchers representing academic institutions, industry, government agencies, not-for-profit organizations and foundations. Objectives:Assessme......Study design:Review by the spinal cord outcomes partnership endeavor (SCOPE), which is a broad-based international consortium of scientists and clinical researchers representing academic institutions, industry, government agencies, not-for-profit organizations and foundations. Objectives......:Assessment of current and evolving tools for evaluating human spinal cord injury (SCI) outcomes for both clinical diagnosis and clinical research studies. Methods:a framework for the appraisal of evidence of metric properties was used to examine outcome tools or tests for accuracy, sensitivity, reliability and validity...... for human SCI. Results:Imaging, neurological, functional, autonomic, sexual health, bladder/bowel, pain and psychosocial tools were evaluated. Several specific tools for human SCI studies have or are being developed to allow the more accurate determination for a clinically meaningful benefit (improvement...

The "neuro-mapping locator" software. A real-time intraoperative objective paraesthesia mapping tool to evaluate paraesthesia coverage of the painful zone in patients undergoing spinal cord stimulation lead implantation.

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Guetarni, F; Rigoard, P

2015-03-01

Conventional spinal cord stimulation (SCS) generates paraesthesia, as the efficacy of this technique is based on the relationship between the paraesthesia provided by SCS on the painful zone and an analgesic effect on the stimulated zone. Although this basic postulate is based on clinical evidence, it is clear that this relationship has never been formally demonstrated by scientific studies. There is a need for objective evaluation tools ("transducers") to transpose electrical signals to clinical effects and to guide therapeutic choices. We have developed a software at Poitiers University hospital allowing real-time objective mapping of the paraesthesia generated by SCS lead placement and programming during the implantation procedure itself, on a touch screen interface. The purpose of this article is to describe this intraoperative mapping software, in terms of its concept and technical aspects. The Neuro-Mapping Locator (NML) software is dedicated to patients with failed back surgery syndrome, candidates for SCS lead implantation, to actively participate in the implantation procedure. Real-time geographical localization of the paraesthesia generated by percutaneous or multicolumn surgical SCS lead implanted under awake anaesthesia allows intraoperative lead programming and possibly lead positioning to be modified with the patient's cooperation. Software updates should enable us to refine objectives related to the use of this tool and minimize observational biases. The ultimate goals of NML software should not be limited to optimize one specific device implantation in a patient but also allow to compare instantaneously various stimulation strategies, by characterizing new technical parameters as "coverage efficacy" and "device specificity" on selected subgroups of patients. Another longer-term objective would be to organize these predictive factors into computer science ontologies, which could constitute robust and helpful data for device selection and programming

Successful spinal cord stimulation for neuropathic below-level spinal cord injury pain following complete paraplegia: a case report.

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Reck, Tim A; Landmann, Gunther

2017-01-01

Neuropathic pain is common in patients with spinal cord injury (SCI) and often difficult to treat. We report a case where epidural spinal cord stimulation (SCS) below the level of injury has been successfully applied in a patient with a complete spinal cord lesion. A 53-year-old female presented with neuropathic below-level SCI pain of both lower legs and feet due to complete SCI below T5. Time and pain duration since injury was 2 years. Pain intensity was reported on numeric rating scale with an average of 7/10 (0 meaning no pain, 10 meaning the worst imaginable pain), but also with about 8-10 pain attacks during the day with an intensity of 9/10, which lasted between some minutes and half an hour. SCS was applied below the level of injury at-level T11-L1. After a successful 2 weeks testing period the pulse generator has been implanted permanently with a burst-stimulation pattern. The average pain was reduced to a bearable intensity of 4/10, in addition attacks could be reduced both in frequency and in intensity. This effects lasted for at least three months of follow-up. Even in case of complete SCI, SCS might be effective. Mechanisms of pain relief remain unclear. A modulation of suggested residual spinothalamic tract function may play a role. Further investigation has to be carried out to support this theory.

Spinal cord contusion.

Science.gov (United States)

Ju, Gong; Wang, Jian; Wang, Yazhou; Zhao, Xianghui

2014-04-15

Spinal cord injury is a major cause of disability with devastating neurological outcomes and limited therapeutic opportunities, even though there are thousands of publications on spinal cord injury annually. There are two major types of spinal cord injury, transaction of the spinal cord and spinal cord contusion. Both can theoretically be treated, but there is no well documented treatment in human being. As for spinal cord contusion, we have developed an operation with fabulous result.

An ovine model of spinal cord injury.

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Wilson, Saul; Abode-Iyamah, Kingsley O; Miller, John W; Reddy, Chandan G; Safayi, Sina; Fredericks, Douglas C; Jeffery, Nicholas D; DeVries-Watson, Nicole A; Shivapour, Sara K; Viljoen, Stephanus; Dalm, Brian D; Gibson-Corley, Katherine N; Johnson, Michael D; Gillies, George T; Howard, Matthew A

2017-05-01

To develop a large animal model of spinal cord injury (SCI), for use in translational studies of spinal cord stimulation (SCS) in the treatment of spasticity. We seek to establish thresholds for the SCS parameters associated with reduction of post-SCI spasticity in the pelvic limbs, with implications for patients. The weight-drop method was used to create a moderate SCI in adult sheep, leading to mild spasticity in the pelvic limbs. Electrodes for electromyography (EMG) and an epidural spinal cord stimulator were then implanted. Behavioral and electrophysiological data were taken during treadmill ambulation in six animals, and in one animal with and without SCS at 0.1, 0.3, 0.5, and 0.9 V. All surgical procedures were carried out at the University of Iowa. The gait measurements were made at Iowa State University. Nine adult female sheep were used in these institutionally approved protocols. Six of them were trained in treadmill ambulation prior to SCI surgeries, and underwent gait analysis pre- and post-SCI. Stretch reflex and H-reflex measurements were also made in conscious animals. Gait analysis revealed repeatable quantitative differences in 20% of the key kinematic parameters of the sheep, pre- and post-SCI. Hock joint angular velocity increased toward the normal pre-injury baseline in the animal with SCS at 0.9 V. The ovine model is workable as a large animal surrogate suitable for translational studies of novel SCS therapies aimed at relieving spasticity in patients with SCI.

[Varices of the vocal cord: report of 21 cases].

Science.gov (United States)

Li, Jin-rang; Sun, Jian-jun

2006-04-01

To study the diagnosis and treatment of varices of the vocal cord. The clinical data of 21 cases with varix of vocal cord were analyzed. All the patients presented hoarseness. There were 15 female and 6 male cases with their ages ranged from 23 to 68 years (median 44 years old). The varix was found on the right vocal cord in 12 cases, on the left vocal cord in 9 cases. Isolated varix existed on the vocal cord in 10 cases, varix with vocal cord polyps or nodules in 10 cases, varix with vocal cord paralysis in 1 case. All the patients were diagnosed under the laryngovideoscopy. The lesions appeared on the superior surface of the vocal cord. Varices manifested as abnormally dilated capillary running in the anterior to posterior direction in 6 cases, as clusters of capillary in 3 cases, as a dot or small sheet or short line of capillary in 12 cases. The varices were disappeared in 2 of 8 cases with vocal cord varices and polyps after removed the polyps. The varices of others patients had no change after following up for more than 6 months, but one patient happened hemorrhage of the contralateral vocal cord. Varices are most commonly seen in female. Laryngovideoscopy is the key in determining the vocal fold varices. Management of patients with a varix includes medical therapy, speech therapy, and occasionally surgical vaporization.

Acute Thoracolumbar Spinal Cord Injury: Relationship of Cord Compression to Neurological Outcome.

Science.gov (United States)

Skeers, Peta; Battistuzzo, Camila R; Clark, Jillian M; Bernard, Stephen; Freeman, Brian J C; Batchelor, Peter E

2018-02-21

Spinal cord injury in the cervical spine is commonly accompanied by cord compression and urgent surgical decompression may improve neurological recovery. However, the extent of spinal cord compression and its relationship to neurological recovery following traumatic thoracolumbar spinal cord injury is unclear. The purpose of this study was to quantify maximum cord compression following thoracolumbar spinal cord injury and to assess the relationship among cord compression, cord swelling, and eventual clinical outcome. The medical records of patients who were 15 to 70 years of age, were admitted with a traumatic thoracolumbar spinal cord injury (T1 to L1), and underwent a spinal surgical procedure were examined. Patients with penetrating injuries and multitrauma were excluded. Maximal osseous canal compromise and maximal spinal cord compression were measured on preoperative mid-sagittal computed tomography (CT) scans and T2-weighted magnetic resonance imaging (MRI) by observers blinded to patient outcome. The American Spinal Injury Association (ASIA) Impairment Scale (AIS) grades from acute hospital admission (≤24 hours of injury) and rehabilitation discharge were used to measure clinical outcome. Relationships among spinal cord compression, canal compromise, and initial and final AIS grades were assessed via univariate and multivariate analyses. Fifty-three patients with thoracolumbar spinal cord injury were included in this study. The overall mean maximal spinal cord compression (and standard deviation) was 40% ± 21%. There was a significant relationship between median spinal cord compression and final AIS grade, with grade-A patients (complete injury) exhibiting greater compression than grade-C and D patients (incomplete injury) (p compression as independently influencing the likelihood of complete spinal cord injury (p compression. Greater cord compression is associated with an increased likelihood of severe neurological deficits (complete injury) following

Development and application of a direct method to observe the implant/bone interface using simulated bone.

Science.gov (United States)

Yamaguchi, Yoko; Shiota, Makoto; FuJii, Masaki; Sekiya, Michi; Ozeki, Masahiko

2016-01-01

Primary stability after implant placement is essential for osseointegration. It is important to understand the bone/implant interface for analyzing the influence of implant design on primary stability. In this study rigid polyurethane foam is used as artificial bone to evaluate the bone-implant interface and to identify where the torque is being generated during placement. Five implant systems-Straumann-Standard (ST), Straumann-Bone Level (BL), Straumann-Tapered Effect (TE), Nobel Biocare-Brånemark MKIII (MK3), and Nobel Biocare-Brånemark MKIV (MK4)-were used for this experiment. Artificial bone blocks were prepared and the implant was installed. After placement, a metal jig and one side artificial bone block were removed and then the implant embedded in the artificial bone was exposed for observing the bone-implant interface. A digital micro-analyzer was used for observing the contact interface. The insertion torque values were 39.35, 23.78, 12.53, 26.35, and 17.79 N cm for MK4, BL, ST, TE, and MK3, respectively. In ST, MK3, TE, MK4, and BL the white layer areas were 61 × 103 μm(2), 37 × 103 μm(2), 103 × 103 μm(2) in the tapered portion and 84 × 03 μm(2) in the parallel portion, 134 × 103 μm(2), and 98 × 103 μm(2) in the tapered portion and 87 × 103 μm(2) in the parallel portion, respectively. The direct observation method of the implant/artificial bone interface is a simple and useful method that enables the identification of the area where implant retention occurs. A white layer at the site of stress concentration during implant placement was identified and the magnitude of the stress was quantitatively estimated. The site where the highest torque occurred was the area from the thread crest to the thread root and the under and lateral aspect of the platform. The artificial bone debris created by the self-tapping blade accumulated in both the cutting chamber and in the space between the threads and artificial bone.

Spinal cord stimulation attenuates temporal summation in patients with neuropathic pain.

Science.gov (United States)

Eisenberg, Elon; Burstein, Yulia; Suzan, Erica; Treister, Roi; Aviram, Joshua

2015-03-01

Evidence has shown that electrical stimulation at the dorsal columns attenuated the "wind-up" phenomenon in dorsal horn neurons in nerve-injured rats. This study was aimed to test the effect of spinal cord stimulation (SCS) on temporal summation (TS), the clinical correlate of the wind-up phenomenon in patients with radicular leg pain. Eighteen patients with SCS implants were tested both 30 minutes after SCS activation ("ON") and 2 hours after turning it off ("OFF"), in a random order. Temporal summation was evaluated in the most painful site in the affected leg and in the corresponding area in the contralateral leg by applying a tonic painful heat stimulus (46.5°C; 120 seconds) and simultaneous recording of the perceived heat pain intensity. Patients were also requested to report their clinical pain intensity (0-100 numerical pain scale) during SCS "ON" and "OFF". The Wilcoxon signed rank test was used in the comparisons between SCS "ON" and "OFF". Spinal cord stimulation activation significantly attenuated clinical pain intensity (from 66 ± 18 to 27 ± 31, P spinal cord neurons, is a possible mechanism underlying SCS analgesia in patients with neuropathic pain.

A Comparative Study of CG CryoDerm and AlloDerm in Direct-to-Implant Immediate Breast Reconstruction

Directory of Open Access Journals (Sweden)

Jun Ho Lee

2013-07-01

Full Text Available Background  To date, various types of acellular dermal matrix (ADM have been developedfor clinical use. AlloDerm is the most familiar type of ADM to most surgeons in breastreconstruction. It is prepared by freeze-drying. CG CryoDerm is the first form of ADM thatrequires no drying process. Therefore,theoretically, it has a higher degree of preservation ofthedermalstructuresthan AlloDerm. We conducted thisstudy to compare the clinical course andpostoperative outcomes of patientswho underwent direct-to-implant breastreconstructionsusing AlloDermand thosewho did using CGCryoDerm.Methods  We performed a retrospective analysis ofthemedicalrecordsin a consecutive seriesof 50 patientswho underwent direct-to-implant breastreconstruction usingAlloDerm(n= 31or CryoDerm (n= 19. We then compared the clinical course and postoperative outcomes ofthe two groups based on the overall incidence of complications

Adeno-associated viral vector-mediated neurotrophin gene transfer in the injured adult rat spinal cord improves hind-limb function

NARCIS (Netherlands)

Blits, B; Oudega, M.; Boer, G J; Bartlett Bunge, M; Verhaagen, J

2003-01-01

To foster axonal growth from a Schwann cell bridge into the caudal spinal cord, spinal cells caudal to the implant were transduced with adeno-associated viral (AAV) vectors encoding for brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (AAV-NT-3). Control rats received AAV vectors encoding

Sonographic findings of normal newborn spinal cord

International Nuclear Information System (INIS)

Park, Chan Sup; Kim, Dong Gyu

1988-01-01

The authors performed spinal cord ultrasonography of 21 healthy newborn infants in Gyeongsang National University Hospital. Normal spinal cord revealed low echogenecity at that of cerebrospinal fluid and was demarcated by intense reflections from its dorsal and ventral surfaces. The central canal was routinely seen as a thin linear reflection in the center of the cord. The nerve roots making up the cauda equina formed a poorly defined collection of intense linear echoes extending from the conus. On real time image, the normal spinal cord exhibited rather slow and rhythmical anteroposterior movement within the subarachnoid fluid. A distinct and rapid vascular pulsation of the spinal cord was usually recognizable. The approximate level of vertebral bodies was determined as follows; most ventrally located vertebral body was thought to be L5 and S1 was seen slightly posterior to the L5 directed inferoposteriorly. According to the above criteria terminal portions of spinal cord were seen around the L2 body in 5 MHz and pointed termination of conus medullaris was clearly seen at L2-3 junction and in upper body of L3 by 7.5 MHz. So it would be better to examine by 5 MHz for spatial orientation and then by 7.5 MHz for more accurate examination. High-resolution, real-time ultrasonography was a safe, rapid screening technique for evaluation of the spinal cord in infants. Additional applications of spinal sonography may be possible in the evaluation of neonatal syringohydromyelia and meningocele as well as intraspinal cyst localization for possible percutaneous puncture by ultrasound guidance

Vocal Cord Dysfunction Masquerading as Astma Like Symptoms

Directory of Open Access Journals (Sweden)

Sami Ozturk

2007-04-01

Full Text Available Vocal cord dysfunction (VCD is a nonorganic disorder of the larynx that involves unintentional paradoxical adduction of the vocal cords while breathing. VCD is a relatively rare condition that may mimic asthma or upper airway obstruction. VCD often coexists with asthma, and should be suspected in any patient in whom asthma treatment fails. Confirming the diagnosis involves direct visualization of abnormal vocal cord motion, and this usually only occurs during symptoms. In this report, we describe a 65-years-old male patient who has psychological problems due to a relative loss, and a military collage student who experiencing respiratory problems during vigorous exercises. [TAF Prev Med Bull 2007; 6(2.000: 148-150

Cord Blood and Transplants

Science.gov (United States)

... donate their baby’s umbilical cord blood to a public cord blood bank. We have more than 249,000 cord blood ... stored as a cord blood unit at a public cord blood bank for future use. It can then be listed ...

Immediate, non-submerged, root-analogue direct laser metal sintering (DLMS) implants: a 1-year prospective study on 15 patients.

Science.gov (United States)

Mangano, Francesco Guido; De Franco, Michele; Caprioglio, Alberto; Macchi, Aldo; Piattelli, Adriano; Mangano, Carlo

2014-07-01

This study evaluated the 1-year survival and success rate of root-analogue direct laser metal sintering (DLMS) implants, placed into the extraction sockets of 15 patients. DLMS is a technology which allows solids with complex geometry to be fabricated by annealing metal powder microparticles in a focused laser beam, according to a computer-generated three-dimensional (3D) model; the fabrication process involves the laser-induced fusion of titanium microparticles, in order to build, layer-by-layer, the desired object. Cone-beam computed tomography (CBCT) acquisition and 3D image conversion, combined with the DLMS process, allow the fabrication of custom-made, root-analogue implants (RAIs). CBCT images of 15 non-restorable premolars (eight maxilla; seven mandible) were acquired and transformed into 3D models: from these, custom-made, root-analogue DLMS implants with integral abutment were fabricated. Immediately after tooth extraction, the RAIs were placed in the sockets and restored with a single crown. One year after implant placement, clinical and radiographic parameters were assessed: success criteria included absence of pain, suppuration, and exudation; absence of implant mobility and absence of continuous peri-implant radiolucency; distance between the implant shoulder and the first visible bone-to-implant contact <1.5 mm from initial surgery; and absence of prosthetic complications. At the 1-year follow-up, no implants were lost, for a survival rate of 100 %. All implants were stable, with no signs of infection. The good conditions of the peri-implant tissues were confirmed by the radiographic examination, with a mean DIB of 0.7 mm (±0.2). The possibility of fabricating custom-made, RAI DLMS implants opens new interesting horizons for immediate placement of dental implants.

An algorithmic programming approach for back pain symptoms in failed back surgery syndrome using spinal cord stimulation with a multicolumn surgically implanted epidural lead: a multicenter international prospective study.

Science.gov (United States)

Rigoard, Philippe; Jacques, Line; Delmotte, Alexandre; Poon, Katherine; Munson, Russell; Monlezun, Olivier; Roulaud, Manuel; Prevost, Audrey; Guetarni, Farid; Bataille, Benoit; Kumar, Krishna

2015-03-01

Many studies have demonstrated the efficacy and the medical/economic value of epidural spinal cord stimulation for the treatment of "failed back surgery syndrome" (FBSS). However, the back pain component of FBSS has been recalcitrant. Recent clinical trials have suggested that multicolumn surgically implanted leads combined with enhanced programming capabilities in the newer implantable pulse generators demonstrate the ability to treat the back pain component of FBSS. The objective of our present international multicentre study is to prospectively evaluate these findings in a larger population. We conducted a prospective, nonrandomized, observational study on 76 patients with refractory FBSS, consecutively implanted with multicolumn spinal cord stimulation (SCS) between 2008 and 2011 in three neurosurgical pain management centers (Poitiers, France; Montréal, Canada; and Regina, Canada). The primary objective of this study was to prospectively analyze the effect of multicolumn lead programming on paresthesia coverage for the back pain region in these patients. The secondary objective was to assess the analgesic efficacy of this technique on the global and back pain components. Paresthesia could be induced in the lower extremities in the majority of patients with at least one of the configurations tested. Bilateral low back paresthesia was induced in 53.5% of patients, while unilateral low back paresthesia was induced in 78.9% of patients. Multicolumn configurations were statistically more effective than monocolumn configurations for all anatomic regions studied. At 6 months, 75.4% of patients receiving multicolumn stimulation (n = 57) obtained at least a 30% improvement of the back pain VAS score, while 42.1% of patients obtained at least a 50% improvement of the back pain VAS score. This study confirms the hypothesis that multicolumn SCS should be considered as an important tool in the treatment of radicular and axial pain in FBSS patients. The efficacy of this

Schwann cell transplantation improves reticulospinal axon growth and forelimb strength after severe cervical spinal cord contusion.

Science.gov (United States)

Schaal, S M; Kitay, B M; Cho, K S; Lo, T P; Barakat, D J; Marcillo, A E; Sanchez, A R; Andrade, C M; Pearse, D D

2007-01-01

Schwann cell (SC) implantation alone has been shown to promote the growth of propriospinal and sensory axons, but not long-tract descending axons, after thoracic spinal cord injury (SCI). In the current study, we examined if an axotomy close to the cell body of origin (so as to enhance the intrinsic growth response) could permit supraspinal axons to grow onto SC grafts. Adult female Fischer rats received a severe (C5) cervical contusion (1.1 mm displacement, 3 KDyn). At 1 week postinjury, 2 million SCs ex vivo transduced with lentiviral vector encoding enhanced green fluorescent protein (EGFP) were implanted within media into the injury epicenter; injury-only animals served as controls. Animals were tested weekly using the BBB score for 7 weeks postimplantation and received at end point tests for upper body strength: self-supported forelimb hanging, forearm grip force, and the incline plane. Following behavioral assessment, animals were anterogradely traced bilaterally from the reticular formation using BDA-Texas Red. Stereological quantification revealed a twofold increase in the numbers of preserved NeuN+ neurons rostral and caudal to the injury/graft site in SC implanted animals, corroborating previous reports of their neuroprotective efficacy. Examination of labeled reticulospinal axon growth revealed that while rarely an axon was present within the lesion site of injury-only controls, numerous reticulospinal axons had penetrated the SC implant/lesion milieu. This has not been observed following implantation of SCs alone into the injured thoracic spinal cord. Significant behavioral improvements over injury-only controls in upper limb strength, including an enhanced grip strength (a 296% increase) and an increased self-supported forelimb hanging, accompanied SC-mediated neuroprotection and reticulospinal axon growth. The current study further supports the neuroprotective efficacy of SC implants after SCI and demonstrates that SCs alone are capable of supporting

Spinal cord stimulators and radiotherapy: First case report and practice guidelines

Directory of Open Access Journals (Sweden)

Walsh Lorraine

2011-10-01

Full Text Available Abstract Spinal cord stimulators (SCS are a well-recognised treatment modality in the management of a number of chronic neuropathic pain conditions, particularly failed back syndrome and radiculopathies. The implantable pulse generator (IPG component of the SCS is designed and operates in a similar fashion to that of a cardiac pacemaker. The IPG consists of an electrical generator, lithium battery, transmitter/receiver and a minicomputer. When stimulated, it generates pulsed electrical signals which stimulate the dorsal columns of the spinal cord, thus alleviating pain. Analogous to a cardiac pacemaker, it can be potentially damaged by ionising radiation from a linear accelerator, in patients undergoing radiotherapy. Herein we report our clinical management of the first reported case of a patient requiring adjuvant breast radiotherapy who had a SCS in situ. We also provide useful practical recommendations on the management of this scenario within a radiation oncology department.

Spinal cord stimulators and radiotherapy: First case report and practice guidelines

International Nuclear Information System (INIS)

Walsh, Lorraine; Guha, Daipayan; Purdie, Thomas G; Bedard, Philippe; Easson, Alexandra; Liu, Fei-Fei; Hodaie, Mojgan

2011-01-01

Spinal cord stimulators (SCS) are a well-recognised treatment modality in the management of a number of chronic neuropathic pain conditions, particularly failed back syndrome and radiculopathies. The implantable pulse generator (IPG) component of the SCS is designed and operates in a similar fashion to that of a cardiac pacemaker. The IPG consists of an electrical generator, lithium battery, transmitter/receiver and a minicomputer. When stimulated, it generates pulsed electrical signals which stimulate the dorsal columns of the spinal cord, thus alleviating pain. Analogous to a cardiac pacemaker, it can be potentially damaged by ionising radiation from a linear accelerator, in patients undergoing radiotherapy. Herein we report our clinical management of the first reported case of a patient requiring adjuvant breast radiotherapy who had a SCS in situ. We also provide useful practical recommendations on the management of this scenario within a radiation oncology department

Cranioplasty with individual titanium implants

Science.gov (United States)

Mishinov, S.; Stupak, V.; Sadovoy, M.; Mamonova, E.; Koporushko, N.; Larkin, V.; Novokshonov, A.; Dolzhenko, D.; Panchenko, A.; Desyatykh, I.; Krasovsky, I.

2017-09-01

Cranioplasty is the second procedure in the history of neurosurgery after trepanation, and it is still relevant despite the development of civilization and progress in medicine. Each cranioplasty operation is unique because there are no two patients with identical defects of the skull bones. The development of Direct Metal Laser Sintering (DMLS) technique opened up the possibility of direct implant printing of titanium, a biocompatible metal used in medicine. This eliminates the need for producing any intermediate products to create the desired implant. We have produced 8 patient-specific titanium implants using this technique for patients who underwent different decompressive cranioectomies associated with bone tumors. Follow-up duration ranged from 6 to 12 months. We observed no implant-related reactions or complications. In all cases of reconstructive neurosurgery we achieved good clinical and aesthetic results. The analysis of the literature and our own experience in three-dimensional modeling, prototyping, and printing suggests that direct laser sintering of titanium is the optimal method to produce biocompatible surgical implants.

The influence of direct laser metal sintering implants on the early stages of osseointegration in diabetic mini-pigs.

Science.gov (United States)

Tan, Naiwen; Liu, Xiangwei; Cai, Yanhui; Zhang, Sijia; Jian, Bo; Zhou, Yuchao; Xu, Xiaoru; Ren, Shuai; Wei, Hongbo; Song, Yingliang

2017-01-01

High failure rates of oral implants have been reported in diabetic patients due to the disruption of osseointegration. The aim of this study was to investigate whether direct laser metal sintering (DLMS) could improve osseointegration in diabetic animal models. Surface characterizations were carried out on two types of implants. Cell morphology and the osteogenic-related gene expression of MG63 cells were observed under conditions of DLMS and microarc oxidation (MAO). A diabetes model in mini-pigs was established by intravenous injection of streptozotocin (150 mg/kg), and a total of 36 implants were inserted into the mandibular region. Micro-computed tomography (micro-CT) and histologic evaluations were performed 3 and 6 months after implantation. The Ra (the average of the absolute height of all points) of MAO surface was 2.3±0.3 µm while the DLMS surface showed the Ra of 27.4±1.1 µm. The cells on DLMS implants spread out more podia than those on MAO implants through cell morphology analysis. Osteogenic-related gene expression was also dramatically increased in the DLMS group. Obvious improvement was observed in the micro-CT and Van Gieson staining analyses of DLMS implants compared with MAO at 3 months, although this difference disappeared by 6 months. DLMS implants showed a higher bone-implant contact percentage (33.2%±11.2%) at 3 months compared with MAO group (18.9%±7.3%) while similar results were showed at 6 months between DLMS group (42.8%±10.1%) and MAO group (38.3%±10.8%). The three-dimensional environment of implant surfaces with highly porous and fully interconnected channel and pore architectures can improve cell spreading and accelerate the progress of osseointegration in diabetic mini-pigs.

New products tissue-engineering in the treatment of spinal cord injury

Science.gov (United States)

Bolshakov, I. N.; Sergienko, V. I.; Kiselev, S. L.; Lagarkova, M. A.; Remigaylo, A. A.; Mihaylov, A. A.; Prokopenko, S. V.

2015-11-01

In the treatment of patients with complicated spinal cord injury the Russian Health spends about one million rubles for each patient in the acute and the interim period after the injury. The number of complicated spinal cord injury is different in geographical areas Russian Federation from 30 to 50 people per 1 million that is affected by the year 5600. Applied to the present surgical and pharmacological techniques provide unsatisfactory results or minimally effective treatment. Transplantation of 100 thousand neuronal mouse predecessors (24 rats) or human neuronal predecessors (18 rats) in the anatomical gap rat spinal cord, followed by analysis of neurological deficit. The neuro-matrix implantation in the rat spinal cord containing 100 thousand neuronal precursors hESC, repeatable control neuro-matrix transplantation, non-cell mass, eliminating neurological deficit for 14 weeks after transplantation about 5-9 points on the scale of the BBB. The cultivation under conditions in vitro human induced pluripotent stem cells on collagen-chitosan matrix (hIPSC) showed that neurons differentiated from induced pluripotent stem cells grown on scaffolds as compact groups and has no neurites. Cells do not penetrate into the matrix during long-term cultivation and formed near the surface of the spherical structures resembling neurospheres. At least 90% of the cells were positive for the neuronal marker tubulin b3. Further studies should be performed to examine the compatibility of neuronal cultures and matrices.

Relationship between the tensile strengths and diameters of human umbilical cords.

Science.gov (United States)

Fernando, D M G; Gamage, S M K; Ranmohottige, S; Weerakkody, I; Abeyruwan, H; Parakrama, H

2018-05-01

Mothers of alleged infanticides might claim that umbilical cord broke during precipitate delivery causing injuries detected on baby at autopsy. There is paucity of evidence regarding this possibility. The objective of the study was to determine relationship between tensile strength and diameter or weight per unit length of cord. Diameters and weights per unit length of fresh umbilical cords were determined. Tensile strengths were measured by Hounsfield Testing Machine. Relationship between tensile strength versus cord diameter and weight per unit length were analyzed. Of 122 cords, average tensile strength, diameter and weight per centimeter were 50.4 N, 7.73 mm and 6.87 g respectively. The tensile strengths were directly proportional to diameter. There was no association between tensile strength and weight per centimeter. Measurement of the diameter of cord is important during autopsy to predict tensile strength and thereby to presume whether cord could have broken by the weight of the baby. Copyright © 2018 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

[Post-traumatic reconnection of the cervical spinal cord with skeletal striated muscles. Study in adult rats and marmosets].

Science.gov (United States)

Horvat, J C; Affane-Boulaid, F; Baillet-Derbin, C; Davarpanah, Y; Destombes, J; Duchossoy, Y; Emery, E; Kassar-Duchossoy, L; Mira, J C; Moissonnier, P; Pécot-Dechavassine, M; Reviron, T; Rhrich-Haddout, F; Tadié, M; Ye, J H

1997-01-01

In an attempt at repairing the injured spinal cord of adult mammals (rat, dog and marmoset) and its damaged muscular connections, we are currently using: 1) peripheral nerve autografts (PNG), containing Schwann cells, to trigger and direct axonal regrowth from host and/or transplanted motoneurons towards denervated muscular targets; 2) foetal spinal cord transplants to replace lost neurons. In adult rats and marmosets, a PNG bridge was used to joint the injured cervical spinal cord to a denervated skeletal muscle (longissimus atlantis [rat] or biceps brachii [rat and marmoset]). The spinal lesion was obtained by the implantation procedure of the PNG. After a post-operative delay ranging from 2 to 22 months, the animals were checked electrophysiologically for functional muscular reconnection and processed for a morphological study including retrograde axonal tracing (HRP, Fast Blue, True Blue), histochemistry (AChE, ATPase), immunocytochemistry (ChAT) and EM. It was thus demonstrated that host motoneurons of the cervical enlargement could extend axons all the way through the PNG bridge as: a) in anaesthetized animals, contraction of the reconnected muscle could be obtained by electrical stimulation of the grafted nerve; b) the retrograde axonal tracing studies indicated that a great number of host cervical neurons extended axons into the PNG bridge up to the muscle; c) many of them were assumed to be motoneurons (double labelling with True Blue and an antibody against ChAT); and even alpha-motoneurons (type C axosomatic synapses in HRP labelled neurons seen in EM in the rat); d) numerous ectopic endplates were seen around the intramuscular tip of the PNG. In larger (cavitation) spinal lesions (rat), foetal motoneurons contained in E14 spinal cord transplants could similarly grow axons through PNG bridges up to the reconnected muscle. Taking all these data into account, it can be concluded that neural transplants are interesting tools for evaluating both the

Self-Assembling Peptide Nanofiber Scaffold Enhanced with RhoA Inhibitor CT04 Improves Axonal Regrowth in the Transected Spinal Cord

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Weiwei Zhang

2012-01-01

Full Text Available The present study was designed to explore the therapeutic potential of self-assembling peptide nanofiber scaffold (SAPNS delivered RhoA inhibitor to ameliorate the hostile microenvironment of injured spinal cord for axonal regeneration. After a transection was applied to the thoracic spinal cord of mice, the combination of SAPNS and CT04 (a cell permeable RhoA inhibitor, single SAPNS with vehicle, or saline was transplanted into the lesion cavity. Results showed that SAPNS+CT04 implants achieved the best therapeutic outcomes among treatment groups. The novel combination not only reconstructed the injured nerve gap but also elicited significant axonal regeneration and motor functional recovery. Additionally, the combination also effectively reduced the apoptosis and infiltration of activated macrophages in the injured spinal cord. Collectively, the present study demonstrated that SAPNS-based delivery of RhoA inhibitor CT04 presented a highly potential therapeutic strategy for spinal cord injury with reknitting lesion gap, attenuating secondary injury, and improving axonal regrowth.

Self-Assembling Peptide Nanofiber Scaffold Enhanced with RhoA Inhibitor CT04 Improves Axonal Regrowth in the Transected Spinal Cord

International Nuclear Information System (INIS)

Weiwei, Z.; Xiaoduo, Z.; Zhongying, L.

2012-01-01

The present study was designed to explore the therapeutic potential of self-assembling peptide nano fiber scaffold (SAPNS) delivered RhoA inhibitor to ameliorate the hostile microenvironment of injured spinal cord for axonal regeneration. After a transection was applied to the thoracic spinal cord of mice, the combination of SAPNS and CT04 (a cell permeable RhoA inhibitor), single SAPNS with vehicle, or saline was transplanted into the lesion cavity. Results showed that SAPNS+CT04 implants achieved the best therapeutic outcomes among treatment groups. The novel combination not only reconstructed the injured nerve gap but also elicited significant axonal regeneration and motor functional recovery. Additionally, the combination also effectively reduced the apoptosis and infiltration of activated macrophages in the injured spinal cord. Collectively, the present study demonstrated that SAPNS-based delivery of RhoA inhibitor CT04 presented a highly potential therapeutic strategy for spinal cord injury with reknitting lesion gap, attenuating secondary injury, and improving axonal regrowth.

Magnetic resonance imaging of malignant extradural tumors with acute spinal cord compression

International Nuclear Information System (INIS)

Lien, H.H.; Blomlie, V.; Heimdal, K.; Norwegian Radium Hospital, Oslo; Norwegian Radium Hospital, Oslo

1990-01-01

Thirty-six cancer patients with extradural spinal metastatic disease and acute symptoms of spinal cord compression underwent magnetic resonance (MR) imaging at 1.5 T. Cord involvement was found in all 36, 7 of whom had lesions at 2 different sites. Vertebral metastases in addition to those corresponding to the cord compressions were detected in 27 patients, and 18 of these had widespread deposits. MR displayed the extent of the tumors in the craniocaudal and lateral directions. The ability to identify multiple sites of cord and vertebral involvement and to delineate tumor accurately makes MR the examination of choice in cancer patients with suspected spinal cord compression. It obviates the need for myelography and postmyelography CT in this group of patients. (orig.)

Preliminary clinical applications of DTI in human cervical spinal cord

International Nuclear Information System (INIS)

Song Ting; Mai Weiwen; Liang Biling; Shen Jun; Huang Suiqiao; Hu Chunhong

2007-01-01

Objective: To condcut preliminary study of the value of DTI(diffusion tensor imaging) in human cervical spinal cord. Methods: Twenty-one patients suffering from cervical spondylotic myelopathy and twenty volunteers without any clinical symptoms underwent routine MRI and DTI examination. DTI was performed in six non-collinear directions with single-shot fast spin echo echo, planar imaging sequence(b value = 400 s·mm -2 ). ADC(apparent diffusion coefficient) and FA(fractional anisotropy)values were measured by ROIs(regions of interest) in 4 different level segment spinal cord (C 2/3 , C 3/4 , C 4/5 , C 5/6 ) in normal volunteers, in lesions and normal segmental spinal cord in clinical cases respectively. DTI original images were automatically processed by using IDL (Version 5.6) soft- ware to produce color tensor images. SPSS11.0 software for windows was used for t-test and one-way ANOVA analysis. The difference was considered statistically significant if P 2/3 , C 3/4 , C 4/5 , C 5/6 , were analyzed and it was found that FA value between them had a significant difference by ANOVA, F=159.24, P 2/3 level. However, ADC value between 4 segments had no significant difference(F=2.191, P>0.05). (2)In patients of cervical spondylotic myelopathy, routine MRI T2WI showed abnormal signal in 9 cases, and showed no abnormal signal in 12 dases. In sixteen cases it was found that abnormal patchy green signal on colorized tensor maps appeared on the normal blue spinal cord. Also, in patients of cervical spondylotic myelopathy, there was significant difference in ADC and FA value between lesions and normal spinal cord (paired t test, for ADC, t=2.88, P 2/3 level segment spinal cord in normal volunteers (0.85 ± 0.03) is the highest among other segments. FA value decreases gradually along cervical spinal cord towards the caudal direction. However, the difference of ADC values amongst 4 segments is not significant. DTI colorized tensor maps can show more lesions than routine MRI

Spinal Cord Injury 101

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Spinal Cord Injury 101

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Full Text Available ... Cord Injury Rehabilitation Pediatric Spinal Cord Injuries Video Library SCI Medical Experts People Living with SCI Personal ... Cord Injury Rehabilitation Pediatric Spinal Cord Injuries Video Library SCI Medical Experts People Living with SCI Personal ...

Spinal Cord Injury 101

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Full Text Available ... Spinal Cord Injury Facts and Figures Care and Treatment After SCI Spinal Cord Injury Rehabilitation Pediatric Spinal ... Spinal Cord Injury Facts and Figures Care and Treatment After SCI Spinal Cord Injury Rehabilitation Pediatric Spinal ...

Spinal Cord Injury 101

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Full Text Available ... Injury Chart Spinal Cord Injury Facts and Figures Care and Treatment After SCI Spinal Cord Injury Rehabilitation ... Injury Chart Spinal Cord Injury Facts and Figures Care and Treatment After SCI Spinal Cord Injury Rehabilitation ...

Spinal Cord Injury 101

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Full Text Available ... Animated Spinal Cord Injury Chart Spinal Cord Injury Facts and Figures Care and Treatment After SCI Spinal ... Animated Spinal Cord Injury Chart Spinal Cord Injury Facts and Figures Care and Treatment After SCI Spinal ...

Non-Uniformity of Ion Implantation in Direct-Current Plasma Immersion Ion Implantation

International Nuclear Information System (INIS)

Cheng-Sen, Liu; Yu-Jia, Fan; Nan, Zhang; Li, Guan; Yuan, Yao; De-Zhen, Wang

2010-01-01

A particle-in-cell simulation is developed to study dc plasma immersion ion implantation. Particular attention is paid to the influence of the voltage applied to the target on the ion path, and the ion flux distribution on the target surface. It is found that the potential near the aperture within the plasma region is not the plasma potential, and is impacted by the voltage applied to the implanted target. A curved equipotential contour expands into the plasma region through the aperture and the extent of the expansion depends on the voltage. Ions accelerated by the electric field in the sheath form a beam shape and a flux distribution on the target surface, which are strongly dependent on the applied voltage. The results of the simulations demonstrate the formation mechanism of the grid-shadow effect, which is in agreement with the result observed experimentally. (physics of gases, plasmas, and electric discharges)

Spinal Cord Diseases

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Your spinal cord is a bundle of nerves that runs down the middle of your back. It carries signals back ... of the spine, this can also injure the spinal cord. Other spinal cord problems include Tumors Infections such ...

Spinal Cord Injury 101

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Full Text Available menu Understanding Spinal Cord Injury What is a Spinal Cord Injury Levels of Injury and What They Mean Animated Spinal Cord Injury Chart Spinal Cord Injury Facts and Figures Care and Treatment After SCI Spinal ...

Development of a non-invasive, multifunctional grasp neuroprosthesis and its evaluation in an individual with a high spinal cord injury.

Science.gov (United States)

Rupp, Rüdiger; Kreilinger, Alex; Rohm, Martin; Kaiser, Vera; Müller-Putz, Gernot R

2012-01-01

Over the last decade the improvement of a missing hand function by application of neuroprostheses in particular the implantable Freehand system has been successfully shown in high spinal cord injured individuals. The clinically proven advantages of the Freehand system is its ease of use, the reproducible generation of two distinct functional grasp patterns and an analog control scheme based on movements of the contralateral shoulder. However, after the Freehand system is not commercially available for more than ten years, alternative grasp neuroprosthesis with a comparable functionality are still missing. Therefore, the aim of this study was to develop a non-invasive neuroprosthesis and to show that a degree of functional restoration can be provided to end users comparable to implanted devices. By introduction of an easy to handle forearm electrode sleeve the reproducible generation of two grasp patterns has been achieved. Generated grasp forces of the palmar grasp are in the range of the implanted system. Though pinch force of the lateral grasp is significantly lower, it can effectively used by a tetraplegic subject to perform functional tasks. The non-invasive grasp neuroprosthesis developed in this work may serve as an easy to apply and inexpensive way to restore a missing hand and finger function at any time after spinal cord injury.

Vocal cord collapse during phrenic nerve-paced respiration in congenital central hypoventilation syndrome.

Science.gov (United States)

Domanski, Mark C; Preciado, Diego A

2012-01-01

Phrenic nerve pacing can be used to treat congenital central hypoventilation syndrome (CCHS). We report how the lack of normal vocal cord tone during phrenic paced respiration can result in passive vocal cord collapse and produce obstructive symptoms. We describe a case of passive vocal cord collapse during phrenic nerve paced respiration in a patient with CCHS. As far as we know, this is the first report of this etiology of airway obstruction. The patient, a 7-year-old with CCHS and normal waking vocal cord movement, continued to require nightly continuous positive airway pressure (CPAP) despite successful utilization of phrenic nerve pacers. On direct laryngoscopy, the patient's larynx was observed while the diaphragmatic pacers were sequentially engaged. No abnormal vocal cord stimulation was witnessed during engaging of either phrenic nerve stimulator. However, the lack of normal inspiratory vocal cord abduction during phrenic nerve-paced respiration resulted in vocal cord collapse and partial obstruction due to passive adduction of the vocal cords through the Bernoulli effect. Bilateral phrenic nerve stimulation resulted in more vocal cord collapse than unilateral stimulation. The lack of vocal cord abduction on inspiration presents a limit to phrenic nerve pacers.

Cycle Training Using Implanted Neural Prostheses: Team Cleveland.

Science.gov (United States)

McDaniel, John; Lombardo, Lisa M; Foglyano, Kevin M; Marasco, Paul D; J Triolo, Ronald

2017-12-05

Recently our laboratory team focused on training five individuals with complete spinal cord injuries for an overground FES bike race in the 2016 Cybathlon held in Zurich Switzerland. A unique advantage team Cleveland had over other teams was the use of implanted pulse generators that provide more selective activation of muscles compared to standard surface stimulation. The advancements in muscle strength and endurance and ultimately cycling power our pilots made during this training period helped propel our competing pilot to win gold at the Cybathlon and allowed our pilots to ride their bikes outside within their communities. Such positive outcomes has encouraged us to further explore more widespread use of FES overground cycling as a rehabilitative tool for those with spinal cord injuries. This review will describes our approach to this race including information on the pilots, stimulation strategy, bike details and training program.

Cycle Training Using Implanted Neural Prostheses: Team Cleveland

Directory of Open Access Journals (Sweden)

John McDaniel

2017-12-01

Full Text Available Recently our laboratory team focused on training five individuals with complete spinal cord injuries for an overground FES bike race in the 2016 Cybathlon held in Zurich Switzerland. A unique advantage team Cleveland had over other teams was the use of implanted pulse generators that provide more selective activation of muscles compared to standard surface stimulation. The advancements in muscle strength and endurance and ultimately cycling power our pilots made during this training period helped propel our competing pilot to win gold at the Cybathlon and allowed our pilots to ride their bikes outside within their communities. Such positive outcomes has encouraged us to further explore more widespread use of FES overground cycling as a rehabilitative tool for those with spinal cord injuries. This review will describes our approach to this race including information on the pilots, stimulation strategy, bike details and training program.

Magnetic resonance imaging of spinal cord syndromes

International Nuclear Information System (INIS)

Einsiedel, H. von; Stepan, R.

1985-01-01

Thirty-four patients with intramedullary space-occupying lesions or cord compression syndromes were examined with a resistive and two different superconductive magnetic resonance (MR) imaging units. Studies were done primarily by the spin-echo (SE) technique and in the majority of patients different pulse sequences were used. Images with short echo-time (TE) and short recovery-time (TR) were best for demonstration of spinal cord anatomy, for depicting cystic portions in intramedullary tumours and for showing syringomyelia. Solid intramedullary tumours showed normal cord signal intensity. Images with prolonged TE and TR predominantly enhanced CSF signal intensity and, to a more considerable extent, solid intramedullary tumours. Thus, the diameter of the subarachnoid space and the presence of a solid intramedullary tumour, not concomittant with a significant enlargement of the spinal cord, could only be recognized on these prolonged SE images. Major advantages of MR in comparison to CT are that the spinal cord can be imaged in the sagittal plane and that beam hardening artifacts do not occur; in comparison to myelography the cord can be imaged directly by MR. Partial volume is a major limitation of MR, not only in the preferably applied sagittal plane. The choice of slice thickness adequate to the diameter of the lesion and straight positioning of the patient for sagittal single slice midline images are fundamental for reliable MR investigations. Another limitation to MR is that cortical bone gives no signal. The actual diameter of the spinal canal therefore cannot be correctly appreciated and consequently it was difficult or impossible to assess spinal stenosis. (orig.)

[Bilateral cochlear implants].

Science.gov (United States)

Müller, J

2017-07-01

Cochlear implants (CI) are standard for the hearing rehabilitation of severe to profound deafness. Nowadays, if bilaterally indicated, bilateral implantation is usually recommended (in accordance with German guidelines). Bilateral implantation enables better speech discrimination in quiet and in noise, and restores directional and spatial hearing. Children with bilateral CI are able to undergo hearing-based hearing and speech development. Within the scope of their individual possibilities, bilaterally implanted children develop faster than children with unilateral CI and attain, e.g., a larger vocabulary within a certain time interval. Only bilateral implantation allows "binaural hearing," with all the benefits that people with normal hearing profit from, namely: better speech discrimination in quiet and in noise, as well as directional and spatial hearing. Naturally, the developments take time. Binaural CI users benefit from the same effects as normal hearing persons: head shadow effect, squelch effect, and summation and redundancy effects. Sequential CI fitting is not necessarily disadvantageous-both simultaneously and sequentially fitted patients benefit in a similar way. For children, earliest possible fitting and shortest possible interval between the two surgeries seems to positively influence the outcome if bilateral CI are indicated.

Spinal Cord Injuries

Science.gov (United States)

... forth between your body and your brain. A spinal cord injury disrupts the signals. Spinal cord injuries usually begin with a blow that fractures or ... down on the nerve parts that carry signals. Spinal cord injuries can be complete or incomplete. With a complete ...

Torakal Ventral Cord Herniation

Directory of Open Access Journals (Sweden)

Sermin Tok

2015-11-01

Full Text Available  Ventral cord herniation is a rare cause of focal myelopathy due to herniation of the thoracic cord through a dural defect.It is also known by a variety of other terms such as spontaneous thoracic cord herniation or idiopathic spinal cord herniation.The key feature is focal distortion and rotation of the cord with no CSF seen between it and the ventral theca.

Acute traumatic central cord syndrome: MRI-pathological correlations

International Nuclear Information System (INIS)

Quencer, R.M.; Bunge, R.P.; Egnor, M.; Green, B.A.; Puckett, W.; Naidich, T.P.; Post, M.J.D.; Norenberg, M.

1992-01-01

The acute traumatic central cord syndrome (ATCCS) is commonly stated to result from an injury which affects primarily the center of the spinal cord and is frequently hemorrhagic. To test the validity of this widely disseminated hypothesis, the magnetic resonance images [MRI] of 11 consecutive cases of ATCCS caused by closed injury to the spine were analyzed and correlated with the gross pathological and histological features of 3 cervical spinal cords obtained at post mortem from patients with ATCCS, including 2 of patients studied by MRI. In this study, the MRI and pathological observations indicate that ATCCS is predominantly a white matter injury and that intramedullary hemorrhage is not a necessary feature of the syndrome; indeed, it is probably an uncommon event in ATCCS. We suggest that the most common mechanism of injury in ATCCS may be direct compression of the cervical spinal cord by buckling of the ligamenta flava into an already narrowed cervical spinal canal; this would explain the predominance of axonal injury in the white matter of the lateral columns. (orig./GDG)

Acute traumatic central cord syndrome: MRI-pathological correlations

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Quencer, R.M. (Dept. of Radiology, Univ. of Miami MRI Center, FL (United States) Miami Project to Cure Paralysis, FL (United States)); Bunge, R.P.; Egnor, M.; Green, B.A. (Miami Project to Cure Paralysis, FL (United States) Dept. of Neurological Surgery, Univ. of Miami School of Medicine, FL (United States)); Puckett, W. (Miami Project to Cure Paralysis, FL (United States)); Naidich, T.P. (Dept. of Radiology, Univ. of Miami MRI Center, FL (United States) Miami Project to Cure Paralysis, FL (United States) Baptist Hospital of Greater Miami, FL (United States)); Post, M.J.D. (Dept. of Radiology, Univ. of Miami MRI Center, FL (United States)); Norenberg, M. (Dept. of Neuropathology, Univ. of Miami School of Medicine, FL (United States))

1992-04-01

The acute traumatic central cord syndrome (ATCCS) is commonly stated to result from an injury which affects primarily the center of the spinal cord and is frequently hemorrhagic. To test the validity of this widely disseminated hypothesis, the magnetic resonance images [MRI] of 11 consecutive cases of ATCCS caused by closed injury to the spine were analyzed and correlated with the gross pathological and histological features of 3 cervical spinal cords obtained at post mortem from patients with ATCCS, including 2 of patients studied by MRI. In this study, the MRI and pathological observations indicate that ATCCS is predominantly a white matter injury and that intramedullary hemorrhage is not a necessary feature of the syndrome; indeed, it is probably an uncommon event in ATCCS. We suggest that the most common mechanism of injury in ATCCS may be direct compression of the cervical spinal cord by buckling of the ligamenta flava into an already narrowed cervical spinal canal; this would explain the predominance of axonal injury in the white matter of the lateral columns. (orig./GDG).

Cell therapy for spinal cord injury informed by electromagnetic waves.

Science.gov (United States)

Finnegan, Jack; Ye, Hui

2016-10-01

Spinal cord injury devastates the CNS, besetting patients with symptoms including but not limited to: paralysis, autonomic nervous dysfunction, pain disorders and depression. Despite the identification of several molecular and genetic factors, a reliable regenerative therapy has yet to be produced for this terminal disease. Perhaps the missing piece of this puzzle will be discovered within endogenous electrotactic cellular behaviors. Neurons and stem cells both show mediated responses (growth rate, migration, differentiation) to electromagnetic waves, including direct current electric fields. This review analyzes the pathophysiology of spinal cord injury, the rationale for regenerative cell therapy and the evidence for directing cell therapy via electromagnetic waves shown by in vitro experiments.

Immediate loading of mandibular overdentures supported by one-piece, direct metal laser sintering mini-implants: a short-term prospective clinical study.

Science.gov (United States)

Mangano, Francesco G; Caprioglio, Alberto; Levrini, Luca; Farronato, Davide; Zecca, Piero A; Mangano, Carlo

2015-02-01

Only a few studies have dealt with immediately loaded, unsplinted mini-implants supporting ball attachment-retained mandibular overdentures (ODs). The aim of this study is to evaluate treatment outcomes of ball attachment-retained mandibular ODs supported by one-piece, unsplinted, immediately loaded, direct metal laser sintering (DMLS) mini-implants. Over a 4-year period (2009 to 2012), all patients referred to the Dental Clinic, University of Varese, and to a private practice for treatment with mandibular ODs were considered for inclusion in this study. Each patient received three or four DMLS mini-implants. Immediately after implant placement, a mandibular OD was connected to the implants. At each annual follow-up session, clinical and radiographic parameters were assessed, including the following outcome measures: 1) implant failures; 2) peri-implant marginal bone loss; and 3) complications. Statistical analysis was conducted using a life-table analysis. A total of 231 one-piece DMLS mini-implants were inserted in 62 patients. After 4 years of loading, six implants failed, giving an overall cumulative survival rate of 96.9%. The mean distance between the implant shoulder and the first visible bone-to-implant contact was 0.38 ± 0.25 and 0.62 ± 0.20 mm at the 1- and 4-year follow-up examinations, respectively. An incidence of 6.0% of biologic complications was reported; prosthetic complications were more frequent (12.9%). Within the limits of this study, it can be concluded that the immediate loading of one-piece, unsplinted, DMLS titanium mini-implants by means of ball attachment-supported mandibular ODs is a successful treatment procedure. Long-term follow-up studies are needed to confirm these results.

Prophylactic Nipple-Sparing Mastectomy and Direct-to-Implant Reconstruction of the Large and Ptotic Breast: Is Preshaping of the Challenging Breast a Key to Success?

Science.gov (United States)

Gunnarsson, Gudjon L; Bille, Camilla; Reitsma, Laurens C; Wamberg, Peter; Thomsen, Jørn Bo

2017-09-01

Nipple-sparing mastectomy with simultaneous hammock technique direct-to-implant reconstruction is increasingly offered to patients opting for risk-reducing mastectomy. Despite this promising method, patients with macromastia and ptotic breasts remain a challenging group to treat satisfactorily and more often end up undergoing a difficult corrective procedure and experience an unacceptably high rate of failed reconstruction. The authors examined whether targeted preshaping mastopexy/reduction could prepare these patients for a successful nipple-sparing mastectomy/direct-to-implant reconstruction. Patients seeking risk-reducing nipple-sparing mastectomy/direct-to-implant reconstruction at the authors' institutions deemed unfit for a one-stage procedure based on their previous experience were offered a targeted two-stage, risk-reducing mastopexy/reduction followed by a delayed secondary nipple-sparing mastectomy and direct-to-implant reconstruction. Patients were followed up at 3 weeks and 6 or 12 months. Forty-four reconstructions were performed in 22 patients aged 43 years (range, 26 to 57 years). All 44 procedures were completed successfully without any failure or nipple-areola complex losses. Patients' median body mass index was 30 kg/m (range, 22 to 44 kg/m). Six patients were smokers and one had hypertension. Two patients underwent reoperation because of hematoma and fat necrosis. The authors' results demonstrate that a targeted preshaping mastopexy/reduction followed by nipple-sparing mastectomy/direct-to-implant reconstruction can be safely planned in women who opt for a risk-reducing mastectomy and can be performed successfully with a 3- to 4-month time span between operations. On the basis of these results and the superior cosmetic outcome, the two-stage approach has become the authors' standard of care in all such settings. Therapeutic, IV.

Spinal Cord Independence Measure, version III: applicability to the UK spinal cord injured population.

Science.gov (United States)

Glass, Clive A; Tesio, Luigi; Itzkovich, Malka; Soni, Bakul M; Silva, Pedro; Mecci, Munawar; Chadwick, Raymond; el Masry, Waghi; Osman, Aheed; Savic, Gordana; Gardner, Brian; Bergström, Ebba; Catz, Amiram

2009-09-01

To examine the validity, reliability and usefulness of the Spinal Cord Independence Measure for the UK spinal cord injury population. Multi-centre cohort study. Four UK regional spinal cord injury centres. Eighty-six people with spinal cord injury. Spinal Cord Independence Measure and Functional Independence Measure on admission analysed using inferential statistics, and Rasch analysis of Spinal Cord Independence Measure. Internal consistency, inter-rater reliability, discriminant validity; Spinal Cord Independence Measure subscale match between distribution of item difficulty and patient ability measurements; reliability of patient ability measures; fit of data to Rasch model; unidimensionality of subscales; hierarchical ordering of categories within items; differential item functioning across patient groups. Scale reliability (kappa coefficients range 0.491-0.835; (p Spinal Cord Independence Measure subscales compatible with stringent Rasch requirements; mean infit indices high; distinct strata of abilities identified; most thresholds ordered; item hierarchy stable across clinical groups and centres. Misfit and differences in item hierarchy identified. Difficulties assessing central cord injuries highlighted. Conventional statistical and Rasch analyses justify the use of the Spinal Cord Independence Measure in clinical practice and research in the UK. Cross-cultural validity may be further improved.

Spinal cord stimulation for FBSS and CRPS: A review of 80 cases with on-table trial of stimulation.

Science.gov (United States)

Gopal, Hari; Fitzgerald, Joseph; McCrory, Connail

2016-01-01

Spinal cord stimulation (SCS) is used for the treatment of chronic neuropathic pain, a notoriously difficult condition to treat. Failed Back Surgery Syndrome (FBSS) and Complex Regional Pain syndrome (CRPS) remain the strongest indications. Funding remains a difficult issue and the use of trial of stimulation is the traditional method of ensuring best outcomes from implantation. A retrospective and consecutive review of 80 cases of spinal cord stimulation for patients with a diagnosis of FBSS and CRPS having undergone prior comprehensive medical management and interventional treatment with no sustained benefit. Trial of stimulation was performed on-table and if acceptable coverage was achieved, the case proceeded to full implantation. The mean patient age was 50.08 years (range 28-80 years). At 12 months follow-up, thirty two patients (40%) no longer required analgesic medication. Thirty patients (37.5%) reported their pain was manageable with first line analgesics. Fourteen (17.5%) reported their pain was manageable first line analgesic and occasional tramadol or codeine. Four (5%) reported that their pain was manageable with NSAID's, paracetamol, amitriptyline, and regular codeine or tramadol. Seventeen out of eighty patients (21.25%) were unemployed before SCS implant, and at 12 months follow up eight of these patients (47.05%) had returned to work. There was no infective complications or explants. Two patients (2.53%) required one lead revision, which was successful. SCS is the most effective treatment for FBSS and CRPS, which is proven resistant to medical management. On-table trial and implantation is easy to perform with good success rate and low morbidity and if successful will reduce complication rates, especially infection.

Microdialysis to optimize cord perfusion and drug delivery in spinal cord injury.

OpenAIRE

Phang, I; Zoumprouli, A; Papadopoulos, MC; Saadoun, S

2016-01-01

OBJECTIVE: There is lack of monitoring from the injury site to guide management of patients with acute traumatic spinal cord injury. Here we describe a bedside microdialysis monitoring technique for optimizing spinal cord perfusion and drug delivery at the injury site. METHODS: 14 patients were recruited within 72 hours of severe spinal cord injury. We inserted intradurally at the injury site a pressure probe, to monitor continuously spinal cord perfusion pressure, and a microdialysis cathete...

Spinal Cord Injury 101

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Spatially Controlled Delivery of siRNAs to Stem Cells in Implants Generated by Multi-Component Additive Manufacturing

DEFF Research Database (Denmark)

Andersen, Morten Østergaard; Le, Dang Quang Svend; Chen, Muwan

2013-01-01

Additive manufacturing is a promising technique in tissue engineering, as it enables truly individualized implants to be made to fit a particular defect. As previously shown, a feasible strategy to produce complex multicellular tissues is to deposit different small interfering RNA (siRNA) in porous...... implants that are subsequently sutured together. In this study, an additive manufacturing strategy to deposit carbohydrate hydrogels containing different siRNAs is applied into an implant, in a spatially controlled manner. When the obtained structures are seeded with mesenchymal stem (stromal) cells......, the selected siRNAs are delivered to the cells and induces specific and localized gene silencing. Here, it is demonstrated how to replicate part of a patient's spinal cord from a computed tomography scan, using an additive manufacturing technique to produce an implant with compartmentalized si...

Spinal Cord Injury 101

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Full Text Available ... Topic Resources Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Spinal Cord Injury 101 Adult Injuries Spinal Cord Injury 101 David ...

Ion implantation

International Nuclear Information System (INIS)

Johnson, E.

1986-01-01

It is the purpose of the present paper to give a review of surface alloy processing by ion implantation. However, rather than covering this vast subject as a whole, the survey is confined to a presentation of the microstructures that can be found in metal surfaces after ion implantation. The presentation is limited to alloys processed by ion implantation proper, that is to processes in which the alloy compositions are altered significantly by direct injection of the implanted ions. The review is introduced by a presentation of the processes taking place during development of the fundamental event in ion implantation - the collision cascade, followed by a summary of the various microstructures which can be formed after ion implantation into metals. This is compared with the variability of microstructures that can be achieved by rapid solidification processing. The microstructures are subsequently discussed in the light of the processes which, as the implantations proceed, take place during and immediately after formation of the individual collision cascades. These collision cascades define the volumes inside which individual ions are slowed down in the implanted targets. They are not only centres for vigorous agitation but also the sources for formation of excess concentrations of point defects, which will influence development of particular microstructures. A final section presents a selection of specific structures which have been observed in different alloy systems. (orig./GSCH)

Clinical observation of Ahmed glaucoma valve implantation for refractory glaucoma by directly puncturing the sclerotic tunnel

Directory of Open Access Journals (Sweden)

Zhi-Ke Xu

2015-02-01

Full Text Available AIM: To observe the clinic effects and complication of Ahmed glaucoma valve(AGVimplantation in refractory glaucoma by using the 23G syringe needle direct puncture the sclerotic tunnel.METHODS: Forty-four cases(44 eyesof refractory glaucoma underwent AGV implantation by useing the 23G syringe needle direct puncture the sclerotic tunnel. The intraocular pressure(IOP, visual acuity, and complication of post-operation were contrasted with those of pre-operation. RESULTS:The success rate was 84.1%, the mean preoperative IOP in research group was 52.1±10.1mmHg, and the last follow up mean IOP was 15.6±6.9mmHg. Compared with the preoperative visual acuity, 11 eyes increased, 27 eyes had no changes and 6 eyes decreased. The main post-operative complications included shallow anterior chamber(4 eyes, choroidal detachment(3 eyes, drainage tube shift(1 eye, hyphema(6 eyes, drainage tube blockage(1 eye, expulsive choroidal hemorrhage(1 eye, and fiber wrap of drainage tray(5 eyes.CONCLUSION: AGV implantation by direct puncture the sclerotic tunnel is feasible and easy. It avoids of making sclerotic petal and the xenogenic sclera transplanting, simplified the operation technique, prevent the leakage of around tube. The shallow anterior chamber rate is lower. It is an effective procedure for refractory glaucoma.

Histological and biomechanical analysis of porous additive manufactured implants made by direct metal laser sintering: a pilot study in sheep.

Science.gov (United States)

Stübinger, Stefan; Mosch, Isabel; Robotti, Pierfrancesco; Sidler, Michéle; Klein, Karina; Ferguson, Stephen J; von Rechenberg, Brigitte

2013-10-01

It was the aim of this study to analyze osseointegrative properties of porous additive manufactured titanium implants made by direct metal laser sintering in a sheep model after an implantation period of 2 and 8 weeks. Three different types of implants were placed in the pelvis of six sheep. In each sheep were placed three standard machined (M), three sandblasted and etched (SE), and three porous additive manufactured (AM) implants. Of these three implants (one per type) were examined histologically and six implants were tested biomechanically. Additionally a semiquantitative histomorphometrical and qualitative fluorescent microscopic analysis were performed. After 2 and 8 weeks bone-to-implant-contact (BIC) values of the AM surface (2w: 20.49% ± 5.18%; 8w: 43.91% ± 9.69%) revealed no statistical significant differences in comparison to the M (2w: 20.33% ± 11.50%; 8w: 25.33% ± 4.61%) and SE (2w: 43.67 ± 12.22%; 8w: 53.33 ± 8.96%) surfaces. AM surface showed the highest increase of the BIC between the two observation time points. Considering the same implantation period histomorphometry and fluorescent labelling disclosed no significant differences in the bone surrounding the three implants groups. In contrast Removal-torque-test showed a significant improve in fixation strength (P ≤ 0.001) for the AM (1891.82 ± 308, 44 Nmm) surface after eight weeks in comparison to the M (198.93±88,04 Nmm) and SE (730.08 ± 151,89 Nmm) surfaces. All three surfaces (M, SE, and AM) showed sound osseointegration. AM implants may offer a possible treatment option in clinics for patients with compromised bone situations. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

A new technique of "midline anchoring" in spinal cord stimulation dramatically reduces lead migration.

Science.gov (United States)

Mironer, Y Eugene; Brown, Christopher; Satterthwaite, John R; Cohen, Mary; Tonder, Lisa M; Grumman, Steve

2004-01-01

Spinal cord stimulation (SCS) is a popular method of treatment of chronic pain. Unfortunately, migration of the lead continues to be a serious complication of this therapy. In an attempt to reduce lateral migration of the SCS lead, we performed a retrospective assessment of a new technique of percutaneous lead placement. This new method of "midline anchoring" of the lead using the plica mediana dorsalis was tested against conventional technique in a retrospective study involving 122 trials and 91 implants of SCS over a period of five years. The use of "midline anchoring" resulted in a decrease in lead migration from 23% to 6% after trial insertion and from 24% to 7% after implantation. We conclude that "midline anchoring" of the SCS lead is an effective method of preventing lead migration.

Detailed analysis of allergic cutaneous reactions to spinal cord stimulator devices

Directory of Open Access Journals (Sweden)

Chaudhry ZA

2013-08-01

Full Text Available Zeshan Ahmed Chaudhry,1 Umer Najib,2 Zahid H Bajwa,3 W Carl Jacobs,4 Javed Sheikh,5 Thomas T Simopoulos61Department of Diagnostic and Interventional Neuroradiology, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA; 2Department of Neurology, Robert C Byrd Health Sciences Center of West Virginia University, Morgantown, WV, USA; 3Boston Headache Institute, Waltham, MA, USA; 4Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA; 5Department of Medicine, Allergy and Immunology, 6Department of Anesthesia, Beth Israel Deaconess Medical Center, Brookline, MA, USAAbstract: The use of spinal cord stimulation (SCS devices to treat chronic, refractory neuropathic pain continues to expand in application. While device-related complications have been well described, inflammatory reactions to the components of these devices remain underreported. In contrast, hypersensitivity reactions associated with other implanted therapies, such as endovascular and cardiac rhythm devices, have been detailed. The purpose of this case series is to describe the clinical presentation and course of inflammatory reactions as well as the histology of these reactions. All patients required removal of the entire device after developing inflammatory reactions over a time course of 1–3 months. Two patients developed a foreign body reaction in the lead insertion wound as well as at the implantable pulse generator site, with histology positive for giant cells. One patient developed an inflammatory dermatitis on the flank and abdomen that resolved with topical hydrocortisone. “In vivo” testing with a lead extension fragment placed in the buttock resulted in a negative reaction followed by successful reimplantation of an SCS device. Inflammatory reactions to SCS devices can manifest as contact dermatitis, granuloma formation, or foreign body reactions with giant cell formation. Tissue diagnosis is essential, and

Design and health care: a study of virtual design and direct metal lasersintering of titanium alloy for the production of customized facial implants

Directory of Open Access Journals (Sweden)

Wilson Kindlein Junior

2009-11-01

Full Text Available The increase in life expectancy and a great number ofaccidents lead to higher demand for medical products,including corrective implants. Patients with tumors or traumas need to replace injured areas in order to restore their aesthetic and structural function. Currently, the available craniofacial implants present a standard geometry and seldom generate satisfactory results. Customized implants, on theother hand, are designed to conform exactly to individual patient’s anatomy. This way, the use of customized implantscan show beneficial effects to the patient and the surgicalteam. In this study, the design and manufacturing of customized implant prior to surgery were described. Implant shape and functional requirements were established by digitaldata based on CT-scans and mirroring operations. The designprocess of customized mandible prosthesis is illustrated as well as its manufacturing process (direct metal laser sinteringand quality control. Laser sintering process and its constraints for the production of customized implants in titanium alloy(Ti-6Al-4V with complex geometry and internal structures are reported.

Spinal Cord Injury 101

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Effects of directional microphone and adaptive multichannel noise reduction algorithm on cochlear implant performance.

Science.gov (United States)

Chung, King; Zeng, Fan-Gang; Acker, Kyle N

2006-10-01

Although cochlear implant (CI) users have enjoyed good speech recognition in quiet, they still have difficulties understanding speech in noise. We conducted three experiments to determine whether a directional microphone and an adaptive multichannel noise reduction algorithm could enhance CI performance in noise and whether Speech Transmission Index (STI) can be used to predict CI performance in various acoustic and signal processing conditions. In Experiment I, CI users listened to speech in noise processed by 4 hearing aid settings: omni-directional microphone, omni-directional microphone plus noise reduction, directional microphone, and directional microphone plus noise reduction. The directional microphone significantly improved speech recognition in noise. Both directional microphone and noise reduction algorithm improved overall preference. In Experiment II, normal hearing individuals listened to the recorded speech produced by 4- or 8-channel CI simulations. The 8-channel simulation yielded similar speech recognition results as in Experiment I, whereas the 4-channel simulation produced no significant difference among the 4 settings. In Experiment III, we examined the relationship between STIs and speech recognition. The results suggested that STI could predict actual and simulated CI speech intelligibility with acoustic degradation and the directional microphone, but not the noise reduction algorithm. Implications for intelligibility enhancement are discussed.

Direct fabrication through electron beam melting technology of custom cranial implants designed in a PHANToM-based haptic environment

International Nuclear Information System (INIS)

Mazzoli, Alida; Germani, Michele; Raffaeli, Roberto

2009-01-01

Repairing critical human skull injuries requires the production and use of customized cranial implants and involves the integration of computer aided design and manufacturing (CAD and CAM). The main causes for large cranial defects are trauma, cranial tumors, infected craniotomy bone flaps and external neurosurgical decompression. The success of reconstructive cranial surgery depends upon: the preoperative evaluation of the defect, the design and manufacturing of the implant, and the skill of the operating surgeon. Cranial implant design is usually carried out manually using CAD although this process is very time-consuming and the quality of the end product depends wholly upon the skill of the operator. This paper presents an alternative automated method for the design of custom-made cranial plates in a PHANToM ® -based haptic environment, and their direct fabrication in biocompatible metal using electron beam melting (EBM) technology.

Spinal Anesthesia and Minimal Invasive Laminotomy for Paddle Electrode Placement in Spinal Cord Stimulation: Technical Report and Clinical Results at Long-Term Followup

Directory of Open Access Journals (Sweden)

S. Sarubbo

2012-01-01

Full Text Available Object. We arranged a mini-invasive surgical approach for implantation of paddle electrodes for SCS under spinal anesthesia obtaining the best paddle electrode placement and minimizing patients’ discomfort. We describe our technique supported by neurophysiological intraoperative monitoring and clinical results. Methods. 16 patients, affected by neuropathic pain underwent the implantation of paddle electrodes for spinal cord stimulation in lateral decubitus under spinal anesthesia. The paddle was introduced after flavectomy and each patient confirmed the correct distribution of paresthesias induced by intraoperative test stimulation. VAS and patients’ satisfaction rate were recorded during the followup and compared to preoperative values. Results. No patients reported discomfort during the procedure. In all cases, paresthesias coverage of the total painful region was achieved, allowing the best final electrode positioning. At the last followup (mean 36.7 months, 87.5% of the implanted patients had a good rate of satisfaction with a mean VAS score improvement of 70.5%. Conclusions. Spinal cord stimulation under spinal anesthesia allows an optimal positioning of the paddle electrodes without any discomfort for patients or neurosurgeons. The best intraoperative positioning allows a better postoperative control of pain, avoiding the risk of blind placements of the paddle or further surgery for their replacement.

A direct plasma injection system into an RFQ for clean and safe ion implantation

International Nuclear Information System (INIS)

Takeuchi, T.; Katayama, T.; Okamura, M.; Yano, K.; Sakumi, A.; Hattori, T.; Hayashizaki, N.; Jameson, R.A.

2002-01-01

A new injection system, direct plasma injection system, was tested and its principle was proved successfully. We found that one of advantages of this injection system was efficient consumption of source materials. Large portions of induced ions can be injected into a first stage accelerator. This feature is quite useful for ion implantation applications, because toxic exhaust gas can be eliminated. In order to utilize this system for industrial application, the feasibility of a boron injection scheme using a Nd:YAG laser system was investigated

Mini-implants in the palatal slope – a retrospective analysis of implant survival and tissue reaction

Directory of Open Access Journals (Sweden)

Ziebura Thomas

2012-11-01

Full Text Available Abstract Background To identify insertion procedure and force application related complications in Jet Screw (JS type mini-implants when inserted in the palatal slope. Methods Setting and Sample Population: The Department of Orthodontics, the University Hospital Münster. Forty-one consecutively started patients treated using mini-implants in the palatal slope. In this retrospective study, 66 JS were evaluated. Patient records were used to obtain data on the mode of utilization and complications. Standardized photographs overlayed with a virtual grid served to test the hypothesis that deviations from the recommended insertion site or the type of mechanics applied might be related to complications regarding bleeding, gingival overgrowth or implant failure. Results Two implants (3% were lost, and two implants (3%, both loaded with a laterally directed force, exhibited loosening while still serving for anchorage. Complications that required treatment did not occur, the most severe problem observed being gingival proliferation which was attributable neither to patients’ age nor to applied mechanics or deviations from the ideal implant position. Conclusions The JS mini-implant is reliable for sagittal and vertical movements or anchorage purposes. Laterally directed forces might be unfavorable. The selection of implant length as well as the insertion procedure should account for the possibility of gingival overgrowth.

Reaction to topical capsaicin in spinal cord injury patients with and without central pain

DEFF Research Database (Denmark)

Finnerup, Nanna Brix; Pedersen, Louise H.; Terkelsen, Astrid J.

2007-01-01

of a spinal cord injury which already is hyperexcitable, would cause enhanced responses in patients with central pain at the level of injury compared to patients without neuropathic pain and healthy controls. Touch, punctuate stimuli, cold stimuli and topical capsaicin was applied above, at, and below injury......Central neuropathic pain is a debilitating and frequent complication to spinal cord injury (SCI). Excitatory input from hyperexcitable cells around the injured grey matter zone is suggested to play a role for central neuropathic pain felt below the level of a spinal cord injury. Direct evidence...... at the level of injury. Keywords: Spinal cord injury; Neuropathic pain; Capsaicin; Neuronal hyperexcitability; Hyperalgesia; Blood flow...

Are Multidimensional Pain Inventory Coping Strategy Profiles Associated with Long-Term Spinal Cord Stimulation Effectiveness?

Science.gov (United States)

Paroli, Mery; Bernini, Olivia; De Carolis, Giuliano; Tollapi, Lara; Bondi, Franca; Martini, Antonella; Dario, Alessandro; Paolicchi, Adriana

2018-05-01

It is acknowledged that the way patients cope with pain may influence treatment outcome. In particular, psychological factors are deemed important when considering patients for suitability for spinal cord stimulation (SCS). The aim of the study is to observe how pre-implantation psychological characteristics impact the effectiveness of SCS for chronic pain. The analysis comprised data from 137 patients who underwent an SCS implant. Screening evaluation included a coping strategies profile (Multidimensional Pain Inventory) and psychiatric disorders (Mini-International Neuropsychiatric Interview). Based on SCS implant outcome collected during follow-up visits, patients were divided into three groups: subjects with long-term pain relief (long-term group), subjects who failed the SCS treatment and decided to explant trial device (trial explanter group [TE]), and those who chose a permanent device (permanent explanter group [PE]). Results showed that most of the patients who failed with the SCS (TE and PE groups) demonstrated a dysfunctional coping profile and showed a higher presence of psychiatric disorders, which significantly influenced the experience and perception of pain. The findings of this study support the value of a multidisciplinary screening. Addressing psychological issues before SCS implantation can reduce the failure rate of SCS.

Effects of Untreated Periodontitis on Osseointegration of Dental Implants in a Beagle Dog Model.

Science.gov (United States)

Lee, Daehyun; Sohn, Byungjin; Kim, Kyoung Hwa; Kim, Sungtae; Koo, Ki-Tae; Kim, Tae-Il; Seol, Yang-Jo; Lee, Yong-Moo; Rhyu, In-Chul; Ku, Young

2016-10-01

There have been previous studies on the relationship between periodontitis and peri-implantitis, but limited information is available on how periodontitis affects osseointegration and wound healing of newly placed dental implants adjacent to natural teeth. The objective of the present experiment is to evaluate healing around dental implants adjacent to teeth with untreated experimental periodontitis. The study included six male beagle dogs. Scaling and plaque control procedures were performed on three dogs (control group). In the other three dogs (experimental group), retraction cords and ligature wires were placed subgingivally around all premolars and the first molars. Induced experimental periodontitis was confirmed after 3 months. Each control or experimental group was divided into two subgroups depending on the timing of implant placement (immediate/delayed). Twelve dental implants (two implants for each dog) were placed immediately, and the other 12 dental implants (two implants for each dog) were placed 2 months after extraction. The animals were sacrificed 2 months after implant placement. Histologic and histometric analyses were performed. Four implants (three from the immediate placement group and one from the delayed placement group) failed in the experimental group. There were significant differences in the percentage of bone-to-implant contact and marginal bone volume density between the control and experimental groups. Both parameters were significantly lower in the experimental group than in the control group (P implants is associated with a higher failure rate compared with delayed placement. Untreated experimental periodontitis was correlated with compromised osseointegration in the implants with delayed placement.

The influence of direct laser metal sintering implants on the early stages of osseointegration in diabetic mini-pigs

Directory of Open Access Journals (Sweden)

Tan NW

2017-07-01

Full Text Available Naiwen Tan,1–3,* Xiangwei Liu,1,2,* Yanhui Cai,4 Sijia Zhang,1,2 Bo Jian,1,2 Yuchao Zhou,1,2 Xiaoru Xu,1,2 Shuai Ren,1,2 Hongbo Wei,1,2 Yingliang Song1,2 1State Key Laboratory of Military Stomatology, National Clinical Research Center for Oral Diseases, Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Xi’an, Shaanxi, China; 2Department of Implant Dentistry, School of Stomatology, The Fourth Military Medical University, Xi’an, Shaanxi, China; 3Department of Stomatology, Hospital 463 of PLA, Xi’an, Shaanxi, China; 4Department of Anesthesiology, Xijing Hospital, The Fourth Military Medical University, Xi’an, Shaanxi, China *These authors contributed equally to this work Background: High failure rates of oral implants have been reported in diabetic patients due to the disruption of osseointegration. The aim of this study was to investigate whether direct laser metal sintering (DLMS could improve osseointegration in diabetic animal models. Methods: Surface characterizations were carried out on two types of implants. Cell morphology and the osteogenic-related gene expression of MG63 cells were observed under conditions of DLMS and microarc oxidation (MAO. A diabetes model in mini-pigs was established by intravenous injection of streptozotocin (150 mg/kg, and a total of 36 implants were inserted into the mandibular region. Micro-computed tomography (micro-CT and histologic evaluations were performed 3 and 6 months after implantation. Results: The Ra (the average of the absolute height of all points of MAO surface was 2.3±0.3 µm while the DLMS surface showed the Ra of 27.4±1.1 µm. The cells on DLMS implants spread out more podia than those on MAO implants through cell morphology analysis. Osteogenic-related gene expression was also dramatically increased in the DLMS group. Obvious improvement was observed in the micro-CT and Van Gieson staining analyses of DLMS implants compared with MAO at 3 months

An oscillating extracellular voltage gradient reduces the density and influences the orientation of astrocytes in injured mammalian spinal cord.

Science.gov (United States)

Moriarty, L J; Borgens, R B

2001-01-01

We have studied the cellular basis for recovery from acute spinal cord injury induced by applied electric fields. We have emphasized this recovery is due to the regeneration of spinal axons around and through the lesion, and have begun to evaluate the contribution of other cells to the recovery process. We have imposed a voltage gradient of about 320 microV/mm across puncture wounds to the adult rat spinal cord in order to study the accumulation and orientation of GFAP+ astrocytes within and adjacent to the lesion. This electric field was imposed by a miniaturized electronic implant designed to alternate the polarity of the field every 15 minutes. Astrocytes are known to undergo hyperplastic transformation within injured mammalian cords forming a major component of the scar that forms in response to injury. We have made three observations using a new computer based morphometry technique: First, we note a slight shift in the orientation of astrocytes parallel to the long axis of the spinal cord towards an imaginary reference perpendicular to this axis by approximately 10 degrees--but only in undamaged white matter near the lesion. Second, the relative number of astrocytes was markedly, and statistically significantly, reduced within electrically--treated spinal cords, particularly in the lesion. Third, the imposed voltage gradient statistically reduced the numbers of astrocytes possessing oriented cell processes within the injury site compared to adjacent undamaged regions of spinal cord.

Intradural approach to selective stimulation in the spinal cord for treatment of intractable pain: design principles and wireless protocol

Science.gov (United States)

Howard, M. A.; Utz, M.; Brennan, T. J.; Dalm, B. D.; Viljoen, S.; Jeffery, N. D.; Gillies, G. T.

2011-08-01

We introduce an intradural approach to spinal cord stimulation for the relief of intractable pain, and describe the biophysical rationale that underlies its design and performance requirements. The proposed device relies on wireless, inductive coupling between a pial surface implant and its epidural controller, and we present the results of benchtop experiments that demonstrate the ability to transmit and receive a frequency-modulated 1.6 MHz carrier signal between micro-coil antennae scaled to the ≈ 1 cm dimensions of the implant, at power levels of about 5 mW. Plans for materials selection, microfabrication, and other aspects of future development are presented and discussed.

Preliminary study of diffusion tensor MR on the cervical spinal cord in normal subjects

International Nuclear Information System (INIS)

Zheng Kuihong; Ma Lin; Guo Xinggao; Liang Li

2006-01-01

Objective: To investigate a simplified and practical strategy for MR diffusion tensor imaging (DTI) of the cervical spinal cord and acquire the normal values of DTI parameters in normal subjects, and to offer the basis for the research of the cervical spinal cord disorders. Methods: DTI examinations were performed in 36 consecutive healthy subjects by using SE-EPI sequence on the cervical spinal cord. The values of apparent diffusion coefficient (ADC), fractional anisotropy (FA), λ 1 , λ 2 , and λ 3 were measured in regions of interest positioned in the normal cervical cords. Results: All 36 subjects completed the examinations. The cervical spinal cords were clearly demonstrated on the postprocessing images, and there were no obvious artifacts on the diffusion tensor images. The average value of ADC was (914.44±82.61) x 10 -6 mm 2 /s and FA was (593.84±52.22) x 10 -3 . The diffusivity components parallel (λ 1 ) and orthogonal (λ 2 and λ 3 ) to the longitudinal axes of the spinal cord were (1585.10±130.07) x 10 -6 mm 2 /s, (559.84±66.49) x 10 -6 mm 2 /s, and (613.28±128.71) x 10 -6 mm 2 /s, respectively. The value of λ 1 was significantly higher than that of λ 2 and λ 3 (P 2 and λ 3 (P>0.05). The value of 2λ 1 /(λ 2 +λ 3 ) was 2.74± 0.32. Conclusion: The normal cervical spinal cord can be well demonstrated in vivo by using DTI with SE-EPI sequence, and various parameters acquired on DTI are stable. The water diffusivity in the direction parallel to the longitudinal axes of the spinal cord is found to be higher than that in directions perpendicular to the longitudinal axes of the spinal cord, thus suggesting the cylindrical anisotropic characteristics in the cervical spinal cord. (authors)

Tracking Changes following Spinal Cord Injury

Science.gov (United States)

Curt, Armin; Friston, Karl; Thompson, Alan

2013-01-01

Traumatic spinal cord injury is often disabling and recovery of function is limited. As a consequence of damage, both spinal cord and brain undergo anatomical and functional changes. Besides clinical measures of recovery, biomarkers that can detect early anatomical and functional changes might be useful in determining clinical outcome—during the course of rehabilitation and recovery—as well as furnishing a tool to evaluate novel treatment interventions and their mechanisms of action. Recent evidence suggests an interesting three-way relationship between neurological deficit and changes in the spinal cord and of the brain and that, importantly, noninvasive magnetic resonance imaging techniques, both structural and functional, provide a sensitive tool to lay out these interactions. This review describes recent findings from multimodal imaging studies of remote anatomical changes (i.e., beyond the lesion site), cortical reorganization, and their relationship to clinical disability. These developments in this field may improve our understanding of effects on the nervous system that are attributable to the injury itself and will allow their distinction from changes that result from rehabilitation (i.e., functional retraining) and from interventions affecting the nervous system directly (i.e., neuroprotection or regeneration). PMID:22730072

Plasma source ion implantation

International Nuclear Information System (INIS)

Conrad, J.R.; Forest, C.

1986-01-01

The authors' technique allows the ion implantation to be performed directly within the ion source at higher currents without ion beam extraction and transport. The potential benefits include greatly increased production rates (factors of 10-1000) and the ability to implant non-planar targets without rastering or shadowing. The technique eliminates the ion extractor grid set, beam raster equipment, drift space and target manipulator equipment. The target to be implanted is placed directly within the plasma source and is biased to a large negative potential so that plasma ions gain energy as they accelerate through the potential drop across the sheath that forms at the plasma boundary. Because the sheath surrounds the target on all sides, all surfaces of the target are implanted without the necessity to raster the beam or to rotate the target. The authors have succeeded in implanting nitrogen ions in a silicon target to the depths and concentrations required for surface treatment of materials like stainless steel and titanium alloys. They have performed ESCA measurements of the penetration depth profile of a silicon target that was biased to 30 kV in a nitrogen discharge plasma. Nitrogen ions were implanted to a depth of 700A at a peak concentration of 30% atomic. The measured profile is quite similar to a previously obtained profile in titanium targets with conventional techniques

Cord Blood Leptin Levels in Gestational Diabetes

Directory of Open Access Journals (Sweden)

Özlem Şengül

2010-08-01

CONCLUSION: In this study there is a minimal clinical effect of cord blood leptin on macrosomia in women with GD, although it is increased in GD and associated with birthweight. Therefore overgrowth may be a result of direct anabolic effect of insulin, rather than indirect effect via leptin.

Spinal Cord Injury 101

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Full Text Available ... arrow What is the “Spinal Cord Injury Model Systems” program? play_arrow What are the most promising new treatments for spinal cord injuries? play_arrow What are the latest developments in the use of electrical stimulation for spinal cord injuries? play_arrow ...

Spinal Cord Injury 101

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Full Text Available ... Abuse and Spinal Cord Injury Allen Heinemann, PhD How Peer Counseling Works Julie Gassaway, MS, RN Pediatric Injuries Pediatric Spinal ... What is a spinal cord injury? play_arrow How does the spinal cord work? play_arrow Why is the level of a ...

Cytoarchitecture of the spinal cord of the postnatal (P4) mouse.

Science.gov (United States)

Sengul, Gulgun; Puchalski, Ralph B; Watson, Charles

2012-05-01

Interpretation of the new wealth of gene expression and molecular mechanisms in the developing mouse spinal cord requires an accurate anatomical base on which data can be mapped. Therefore, we have assembled a spinal cord atlas of the P4 mouse to facilitate direct comparison with the adult specimens and to contribute to studies of the development of the mouse spinal cord. This study presents the anatomy of the spinal cord of the P4 C57Bl/6J mouse using Nissl and acetyl cholinesterase-stained sections. It includes a detailed map of the laminar organization of selected spinal cord segments and a description of named cell groups of the spinal cord such as the central cervical (CeCv), lateral spinal nucleus, lateral cervical, and dorsal nuclei. The motor neuron groups have also been identified according to the muscle groups they are likely to supply. General features of Rexed's laminae of the P4 spinal cord showed similarities to that of the adult (P56). However, certain differences were observed with regard to the extent of laminae and location of certain cell groups, such as the dorsal nucleus having a more dispersed structure and a more ventral and medial position or the CeCv being located in the medial part of lamina 5 in contrast to the adult where it is located in lamina 7. Motor neuron pools appeared to be more tightly packed in the P4 spinal cord. The dorsal horn was relatively larger and there was more white matter in the P56 spinal cord. Copyright © 2012 Wiley Periodicals, Inc.

Experimental study on bone tissue reaction around HA implants radiated after implantation

International Nuclear Information System (INIS)

Kudo, Masato; Matsui, Yoshiro; Tamura, Sayaka; Chen, Xuan; Uchida, Haruo; Mori, Kimie; Ohno, Kohsuke; Michi, Ken-ichi

1998-01-01

This study was conducted to investigate histologically and histomorphometrically the tissue reaction around hydroxylapatite (HA) implants that underwent irradiation in 3 different periods in the course of bone healing after implantation. The cylindrical high-density HA implants were implanted in 48 Japanese white rabbit mandibles. A single 15 Gy dose was applied to the mandible 5, 14, or 28 days after implantation. The rabbits were sacrificed 7, 14, 28, and 90 days after irradiation. Nonirradiated rabbits were used as controls. CMR, labeling with tetracycline and calcein, and non-decalcified specimens stained with toluidine blue were used for histological analyses and histomorphometric measurements. The results were as follows: In the rabbits irradiated 5 days after implantation, the HA-bone contact was observed later than that in the controls and the bone-implant contact surface ratio was lower than that in the controls at examination because necrosis of the newly-formed bone occurred just after irradiation. HA-bone contact of the rabbits irradiated 14 and 28 days after implantation was similar to that of the controls. And, bone remodeling was suppressed in rabbits of each group sacrificed at 90 days after irradiation. The results suggested that a short interval between implantation and irradiation causes direct contact between HA implant and bone and a long lapse of time before irradiation hardly affects the bone-implant contact, but delays bone remodeling. Therefore, it is necessary to prevent overloading the HA implants irradiated after implantation and pay utmost attention to conditions around the bone-implant contact. (author)

Systemic hypothermia for the treatment of acute cervical spinal cord injury in sports.

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Dietrich, William Dalton; Cappuccino, Andrew; Cappuccino, Helen

2011-01-01

Spinal cord injury is a devastating condition that affects approximately 12,000 patients each year in the United States. Major causes for spinal cord injury include motor vehicle accidents, sports-related injuries, and direct trauma. Moderate hypothermia has gained attention as a potential therapy due to recent experimental and clinical studies and the use of modest systemic hypothermia (MSH) in high profile case of spinal cord injury in a National Football League (NFL) player. In experimental models of spinal cord injury, moderate hypothermia has been shown to improve functional recovery and reduce overall structural damage. In a recent Phase I clinical trial, systemic hypothermia has been shown to be safe and provide some encouraging results in terms of functional recovery. This review will summarize recent preclinical data, as well as clinical findings that support the continued investigations for the use of hypothermia in severe cervical spinal cord injury.

Direct observation and mechanism for enhanced field emission sites in platinum ion implanted/post-annealed ultrananocrystalline diamond films

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Panda, Kalpataru, E-mail: panda@afm.eei.eng.osaka-u.ac.jp, E-mail: phy.kalpa@gmail.com; Inami, Eiichi; Sugimoto, Yoshiaki [Graduate School of Engineering, Osaka University, 2-1, Yamada-Oka, Suita, Osaka 565-0871 (Japan); Sankaran, Kamatchi J.; Tai, Nyan Hwa [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Lin, I-Nan, E-mail: inanlin@mail.tku.edu.tw [Department of Physics, Tamkang University, Tamsui 251, Taiwan (China)

2014-10-20

Enhanced electron field emission (EFE) properties for ultrananocrystalline diamond (UNCD) films upon platinum (Pt) ion implantation and subsequent post-annealing processes is reported, viz., low turn-on field of 4.17 V/μm with high EFE current density of 5.08 mA/cm{sup 2} at an applied field of 7.0 V/μm. Current imaging tunneling spectroscopy (CITS) mode in scanning tunneling spectroscopy directly revealed the increased electron emission sites density for Pt ion implanted/post-annealed UNCD films than the pristine one. The high resolution CITS mapping and local current–voltage characteristic curves demonstrated that the electrons are dominantly emitted from the diamond grain boundaries and Pt nanoparticles.

Direct observation and mechanism for enhanced field emission sites in platinum ion implanted/post-annealed ultrananocrystalline diamond films

International Nuclear Information System (INIS)

Panda, Kalpataru; Inami, Eiichi; Sugimoto, Yoshiaki; Sankaran, Kamatchi J.; Tai, Nyan Hwa; Lin, I-Nan

2014-01-01

Enhanced electron field emission (EFE) properties for ultrananocrystalline diamond (UNCD) films upon platinum (Pt) ion implantation and subsequent post-annealing processes is reported, viz., low turn-on field of 4.17 V/μm with high EFE current density of 5.08 mA/cm 2 at an applied field of 7.0 V/μm. Current imaging tunneling spectroscopy (CITS) mode in scanning tunneling spectroscopy directly revealed the increased electron emission sites density for Pt ion implanted/post-annealed UNCD films than the pristine one. The high resolution CITS mapping and local current–voltage characteristic curves demonstrated that the electrons are dominantly emitted from the diamond grain boundaries and Pt nanoparticles.

Evaluation of spinal cord vessels using multi-slice CT angiography

International Nuclear Information System (INIS)

Chen Shuang; Zhu Ruijiang; Feng Xiaoyuan

2006-01-01

Objective: To evaluate the value of Multi-slice spiral CT angiography for spinal cord vessels. Methods: 11 adult subjects with suspected of myelopathy were performed with Multi-slice spiral CT angiography, An iodine contrast agent was injected at 3.5 ml/s, for total 100 ml. The parameters were axial 16 slice mode, 0.625 mm slice thickness, 0.8 s rotation, delay time depending on smartprep(15-25 s), multi-phase scan. The coronal and sagittal MPR and SSD were generated on a workstation compared with spinal digital subtraction angiography (DSA) to analyze normal or abnormal spinal cord vessels. Results: Normal findings at spinal CTA and digital subtraction angiography in six adult normal subjects and spinal cord vascular malformations (1 intradural extramedullary AVF, 4 dural AVFs) in five cases, Recognizable intradural vessels corresponding to anterior median (midline) veins and/or anterior spinal arteries were show in six adult normal subjects. Abnormal intradural vessels were detected in all five spinal cord vascular malformation with CT angiography, in comparison with digital subtraction angiography these vessels were primarily enlarged veins of the coronal venous plexus on the cord surface, radiculomedullary-dural arteries could not be clearly shown in four dural AVF, only one anterior spinal artery was detected in one patient with intradural medullary AVF, which direct shunt between anterior spinal artery and perimedullary vein with tortuous draining vessel. Conclusion: Multi-slice CT angiography is able to visualize the normal or abnormal spinal cord vessels. It could be used as a noninvasive method to screen the spinal cord vascular disease. (authors)

Spinal Cord Injury 101

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Full Text Available ... the spinal cord work? play_arrow Why is the level of a spinal cord injury important? play_arrow What role does “compression” play in a spinal cord injury? play_arrow Why are high-dose steroids often used right after an injury? play_arrow What is meant ...

Human amniotic epithelial cells combined with silk fibroin scaffold in the repair of spinal cord injury

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Ting-gang Wang

2016-01-01

Full Text Available Treatment and functional reconstruction after central nervous system injury is a major medical and social challenge. An increasing number of researchers are attempting to use neural stem cells combined with artificial scaffold materials, such as fibroin, for nerve repair. However, such approaches are challenged by ethical and practical issues. Amniotic tissue, a clinical waste product, is abundant, and amniotic epithelial cells are pluripotent, have low immunogenicity, and are not the subject of ethical debate. We hypothesized that amniotic epithelial cells combined with silk fibroin scaffolds would be conducive to the repair of spinal cord injury. To test this, we isolated and cultured amniotic epithelial cells, and constructed complexes of these cells and silk fibroin scaffolds. Implantation of the cell-scaffold complex into a rat model of spinal cord injury resulted in a smaller glial scar in the damaged cord tissue than in model rats that received a blank scaffold, or amniotic epithelial cells alone. In addition to a milder local immunological reaction, the rats showed less inflammatory cell infiltration at the transplant site, milder host-versus-graft reaction, and a marked improvement in motor function. These findings confirm that the transplantation of amniotic epithelial cells combined with silk fibroin scaffold can promote the repair of spinal cord injury. Silk fibroin scaffold can provide a good nerve regeneration microenvironment for amniotic epithelial cells.

Spinal cord stimulation

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... this page: //medlineplus.gov/ency/article/007560.htm Spinal cord stimulation To use the sharing features on this page, please enable JavaScript. Spinal cord stimulation is a treatment for pain that uses ...

Spinal cord stimulation for cancer-related pain in adults.

Science.gov (United States)

Peng, Lihua; Min, Su; Zejun, Zhou; Wei, Ke; Bennett, Michael I

2015-06-29

This is an update of a review first published in The Cochrane Library in Issue 3, 2013. Cancer-related pain places a heavy burden on public health with related high expenditure. Severe pain is associated with a decreased quality of life in patients with cancer. A significant proportion of patients with cancer-related pain are under-treated. There is a need for more effective control of cancer-related pain. Spinal cord stimulation (SCS) may have a role in pain management. The effectiveness and safety of SCS for patients with cancer-related pain is currently unknown. This systematic review evaluated the effectiveness of SCS for cancer-related pain compared with standard care using conventional analgesic medication. We also appraised risk and potential adverse events associated with the use of SCS. This is an update of a review first published in The Cochrane Library in Issue 3, 2013. The search strategy for the update was the same as in the original review. We searched the following bibliographic databases in order to identify relevant studies: the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library; MEDLINE; EMBASE; and CBM (Chinese Biomedical Database) in October 2014. We also handsearched relevant journals. There were no language restrictions. We planned to include randomised controlled trials (RCTs) that directly compared SCS with other interventions with regards to the effectiveness of pain management. We also planned to include cross-over trials that compared SCS with another treatment. We planned to identify non-randomised controlled trials but these would only be included if no RCTs could be found. The literature search for the update of this review found 121 potentially eligible articles. The initial search strategy yielded 430 articles. By scrutinising titles and abstracts, we found 412 articles irrelevant to the analytical purpose of this systematic review due to different scopes of diseases or different methods of intervention

Strain driven fast osseointegration of implants

Directory of Open Access Journals (Sweden)

Wiesmann Hans-Peter

2005-09-01

Full Text Available Abstract Background Although the bone's capability of dental implant osseointegration has clinically been utilised as early as in the Gallo-Roman population, the specific mechanisms for the emergence and maintenance of peri-implant bone under functional load have not been identified. Here we show that under immediate loading of specially designed dental implants with masticatory loads, osseointegration is rapidly achieved. Methods We examined the bone reaction around non- and immediately loaded dental implants inserted in the mandible of mature minipigs during the presently assumed time for osseointegration. We used threaded conical titanium implants containing a titanium2+ oxide surface, allowing direct bone contact after insertion. The external geometry was designed according to finite element analysis: the calculation showed that physiological amplitudes of strain (500–3,000 ustrain generated through mastication were homogenously distributed in peri-implant bone. The strain-energy density (SED rate under assessment of a 1 Hz loading cycle was 150 Jm-3 s-1, peak dislocations were lower then nm. Results Bone was in direct contact to the implant surface (bone/implant contact rate 90% from day one of implant insertion, as quantified by undecalcified histological sections. This effect was substantiated by ultrastructural analysis of intimate osteoblast attachment and mature collagen mineralisation at the titanium surface. We detected no loss in the intimate bone/implant bond during the experimental period of either control or experimental animals, indicating that immediate load had no adverse effect on bone structure in peri-implant bone. Conclusion In terms of clinical relevance, the load related bone reaction at the implant interface may in combination with substrate effects be responsible for an immediate osseointegration state.

Cervical spinal cord, root, and bony spine injuries: a closed claims analysis.

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Hindman, Bradley J; Palecek, John P; Posner, Karen L; Traynelis, Vincent C; Lee, Lorri A; Sawin, Paul D; Tredway, Trent L; Todd, Michael M; Domino, Karen B

2011-04-01

The aim of this study was to characterize cervical cord, root, and bony spine claims in the American Society of Anesthesiologists Closed Claims database to formulate hypotheses regarding mechanisms of injury. All general anesthesia claims (1970-2007) in the Closed Claims database were searched to identify cervical injuries. Three independent teams, each consisting of an anesthesiologist and neurosurgeon, used a standardized review form to extract data from claim summaries and judge probable contributors to injury. Cervical injury claims (n = 48; mean ± SD age 47 ± 15 yr; 73% male) comprised less than 1% of all general anesthesia claims. When compared with other general anesthesia claims (19%), cervical injury claims were more often permanent and disabling (69%; P cervical stenosis) were often present, cord injuries usually occurred in the absence of traumatic injury (81%) or cervical spine instability (76%). Cord injury occurred with cervical spine (65%) and noncervical spine (35%) procedures. Twenty-four percent of cord injuries were associated with the sitting position. Probable contributors to cord injury included anatomic abnormalities (81%), direct surgical complications (24% [38%, cervical spine procedures]), preprocedural symptomatic cord injury (19%), intraoperative head/neck position (19%), and airway management (11%). Most cervical cord injuries occurred in the absence of traumatic injury, instability, and airway difficulties. Cervical spine procedures and/or sitting procedures appear to predominate. In the absence of instability, cervical spondylosis was the most common factor associated with cord injury.

Direct implantation versus platelet-rich fibrin-embedded adipose-derived mesenchymal stem cells in treating rat acute myocardial infarction.

Science.gov (United States)

Sun, Cheuk-Kwan; Zhen, Yen-Yi; Leu, Steve; Tsai, Tzu-Hsien; Chang, Li-Teh; Sheu, Jiunn-Jye; Chen, Yung-Lung; Chua, Sarah; Chai, Han-Tan; Lu, Hung-I; Chang, Hsueh-Wen; Lee, Fan-Yen; Yip, Hon-Kan

2014-05-15

This study tested whether adipose-derived mesenchymal stem cells (ADMSC) embedded in platelet-rich fibrin (PRF) scaffold is superior to direct ADMSC implantation in improving left ventricular (LV) performance and reducing LV remodeling in a rat acute myocardial infarction (AMI) model of left anterior descending coronary artery (LAD) ligation. Twenty-eight male adult Sprague Dawley rats equally divided into group 1 [sham control], group 2 (AMI only), group 3 (AMI+direct ADMSC implantation), and group 4 (AMI+PRF-embedded autologous ADMSC) were sacrificed on day 42 after AMI. LV systolic and diastolic dimensions and volumes, and infarct/fibrotic areas were highest in group 2, lowest in group 1 and significantly higher in group 3 than in group 4, whereas LV performance and LV fractional shortening exhibited a reversed pattern (p<0.005). Protein expressions of inflammation (oxidative stress, IL-1β, MMP-9), apoptosis (mitochondrial Bax, cleaved PARP), fibrosis (Smad3, TGF-β), and pressure-overload biomarkers (BNP, MHC-β) displayed a pattern similar to that of LV dimensions, whereas anti-inflammatory (IL-10), anti-apoptotic (Bcl-2), and anti-fibrotic (Smad1/5, BMP-2) indices showed a pattern similar to that of LV performance among the four groups (all p<0.05). Angiogenesis biomarkers at protein (CXCR4, SDF-1α, VEGF), cellular (CD31+, CXCR4+, SDF-1α+), and immunohistochemical (small vessels) levels, and cardiac stem cell markers (C-kit+, Sca-1+) in infarct myocardium were highest in group 4, lowest in group 1, and significantly higher in group 3 than in group 2 (all p<0.005). PRF-embedded ADMSC is superior to direct ADMSC implantation in preserving LV function and attenuating LV remodeling. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Spinal Cord Injury 101

Medline Plus

Full Text Available ... injury? play_arrow How does the spinal cord work? play_arrow Why is the level of a spinal cord injury important? play_arrow What role does “compression” play in a spinal cord injury? play_arrow Why are high-dose steroids often used right after an injury? play_arrow What is meant ...

Electrical enhancement of direct methanol fuel cells by metal-plasma ion implantation Pt-Ru/C multilayer catalysts.

Science.gov (United States)

Weng, Ko-Wei; Chen, Yung-Lin; Chen, Ya-Chi; Lin, Tai-Nan

2009-02-01

Direct methanol fuel cells (DMFC) have been widely studied owing to their simple cell configuration, high volume energy density, short start-up time, high operational reliability and other favorable characteristics. However, major limitations include high production cost, poisoning of the catalyst and methanol crossover. This study adopts a simple technique for preparing Pt-Ru/C multilayer catalysts, including magnetron sputtering (MS) and metal-plasma ion implantation (MPII). The Pt catalysts were sputtered onto the gas diffusion layer (GDL), followed by the implantation of Ru catalysts using MPII (at an accelerating voltage of 20 kV and an implantation dose of 1 x 10(16) ions/cm2). Pt-Ru is repeatedly processed to prepare Pt-Ru/C multilayer catalysts. The catalyst film structure and microstructure were analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electronic microscopy (SEM), respectively. The cell performance was tested using a potential stat/galvano-stat. The results reveal that the membrane electrode assembly (MEA) of four multilayer structures enhances the cell performance of DMFC. The measured power density is 2.2 mW/cm2 at a methanol concentration of 2 M, with an OCV of 0.493 V.

Umbilical cord sparing technique for repair of congenital hernia into the cord and small omphalocele.

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Ceccanti, Silvia; Falconi, Ilaria; Frediani, Simone; Boscarelli, Alessandro; Musleh, Layla; Cozzi, Denis A

2017-01-01

Current repair of small omphaloceles and hernias into the umbilical cord is a straightforward procedure, whose repair may result in a suboptimal cosmetic outcome. We describe a novel repair technique retaining the umbilical cord elements in an attempt to improve the cosmetic appearance of the umbilicus. Eight neonates were consecutively treated more than a ten-year period. Size of the fascial defects ranged 1 to 3cm (median, 2). Present technique entails incision of the amniotic sac without its detachment from the skin, reduction of the extruded contents under direct vision, and closure of the abdominal wall defect by circumferential suturing of peritoneum and fascia around the base of the amniotic sac. The amniotic sac is then re-approximated and folded to create an umbilical stump, which is trimmed and left to shed naturally. All patients achieved a scarless abdomen with a normal appearing umbilicus in 6. The remaining 2 patients are awaiting surgery for persisting umbilical hernia repair and umbilicoplasty, respectively. Poor esthetic outcome was significantly associated with initial fascial defect ≥2.5cm in size (p=0.03). Present technique is a simple and cosmetically appealing repair for umbilical cord hernias and small omphaloceles, especially effective when the size of the fascial defect is less than 2.5cm. IV (Treatment Study). Copyright © 2017 Elsevier Inc. All rights reserved.

Bone marrow stem cells delivered into the subarachnoid space via cisterna magna improve repair of injured rat spinal cord white matter

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Marcol, Wiesław; Slusarczyk, Wojciech; Sieroń, Aleksander L; Koryciak-Komarska, Halina; Lewin-Kowalik, Joanna

2015-01-01

The influence of bone marrow stem cells on regeneration of spinal cord in rats was investigated. Young adult male Wistar rats were used (n=22). Focal injury of spinal cord white matter at Th10 level was produced using our original non-laminectomy method by means of high-pressured air stream. Cells from tibial and femoral bone marrow of 1-month old rats (n=3) were cultured, labeled with BrdU/Hoechst and injected into cisterna magna (experimental group) three times: immediately after spinal cord injury and 3 as well as 7 days later. Neurons in brain stem and motor cortex were labeled with FluoroGold (FG) delivered caudally from the injury site a week before the end of experiment. Functional outcome and morphological features of regeneration were analyzed during 12-week follow-up. The lesions were characterized by means of MRI. Maximal distance of expansion of implanted cells in the spinal cord was measured and the number of FG-positive neurons in the brain was counted. Rats treated with stem cells presented significant improvement of locomotor performance and spinal cord morphology when compared to the control group. Distance covered by stem cells was 7 mm from the epicenter of the injury. Number of brain stem and motor cortex FG-positive neurons in experimental group was significantly higher than in control. Obtained data showed that bone marrow stem cells are able to induce the repair of injured spinal cord white matter. The route of cells application via cisterna magna appeared to be useful for their delivery in spinal cord injury therapy. PMID:26628950

Cord Blood Chimerism And Relapse After Haplo-Cord Transplantation

Science.gov (United States)

van Besien, Koen; Koshy, Nebu; Gergis, Usama; Mayer, Sebastian; Cushing, Melissa; Rennert, Hannah; Slotky, Ronit; Mark, Tomer; Pearse, Roger; Rossi, Adriana; Phillips, Adrienne; Vasovic, Liljana; Ferrante, Rosanna; Hsu, Michael; Shore, Tsiporah

2018-01-01

Haplo-cord stem cell transplantation combines the infusion of CD34 selected hematopoietic progenitors from a haplo-identical donor with an umbilical cord blood graft from an unrelated donor and allows faster count recovery, with low rates of disease recurrence and chronic GVHD. But the contribution of the umbilical cord blood graft to long-term transplant outcome remains unclear. We analyzed 39 recipients of haplo-cord transplants with AML and MDS, engrafted and in remission at 2 months. Median age was 66 (18-72) and all had intermediate, high, or very high risk disease. Less than 20% UCB chimerism in the CD33 lineage was associated with an increased rate of disease recurrence (54% vs 11% Pdisease recurrence (46% vs 12%, P=0.007) Persistent haplo-chimerism in the CD3 lineage was associated with an increased rate of disease recurrence (40% vs 15%, P=0.009) Chimerism did not predict for treatment related mortality. The cumulative incidence of acute GVHD by day 100 was 43%. The cumulative incidence of moderate/severe chronic GVHD was only 5%. Engraftment of the umbilical cord blood grafts provides powerful GVL effects which protect against disease recurrence and is associated with low risk of chronic GVHD. Engraftment of CD34 selected haplo-identical cells can lead to rapid development of circulating T-cells, but when these cells dominate, GVL-effects are limited and rates of disease recurrence are high. PMID:27333804

Fixed cord in spinal stenosis

International Nuclear Information System (INIS)

Levy, L.M.; Wang, H.; Francomano, C.; Hurko, O.; Carson, B.; Heffez, D.S.; DiChiro, G.; Bryan, R.N.

1990-01-01

This paper evaluates patients with cervical spinal canal compromise due to congenital anomalies (achondroplasia, Chiari malformation) and degenerative diseases using MR cord motion and cerebrospinal fluid (CSF) flow studies. Pulsatile longitudinal motion of the cervical cord was determined by means of cardiac-gated velocity phase contrast methods, including cine. Pathology included dwarfism (n = 15), Chiari malformation (n = 10), spondylosis (n = 10), and acute cord compression (n = 9). Symptomatic cases of congenital cervical stenosis had decreased cord motion, although CSF flow was not always significantly compromised. Postoperative cases demonstrated good cord and CSF motion, unless compression or obstruction was present

A Comparison of implant impression precision: Different materials and techniques

Science.gov (United States)

Tabesh, Mahtab; Alikhasi, Marzieh

2018-01-01

Background Precision of implant impressions is a prerequisite for long-term success of implant supported prostheses. Impression materials and impression techniques are two important factors that impression precision relies on. Material and Methods A model of edentulous maxilla containing four implants inserted by All-on-4 guide was constructed. Seventy two impressions using polyether (PE), polyvinyl siloxane (PVS), and vinyl siloxanether (VSE) materials with direct and indirect techniques were made (n=12). Coordinates of implants in casts were measured using coordinate measuring machine (CMM). Data were analyzed with ANOVA; t-test and Tukey test were used for post hoc. Results With two-way ANOVA, mean values of linear displacements of implants were significantly different among materials and techniques. One-way ANOVA and Tukey showed significant difference between PE and VSE (P=0.019), PE and PVS (P=0.002) in direct technique, and between PVS and PE (Pimpression of implants, PE is recommended for direct technique while PE and VSE are recommended for indirect technique. Recommended technique for VSE is either direct or indirect; and for PE and PVS is direct. Key words:Polyvinyl siloxane, polyether, vinyl siloxanether, direct technique, indirect technique, All-on-4, coordinate measuring machine. PMID:29670733

Metals for bone implants. Part 1. Powder metallurgy and implant rendering.

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Andani, Mohsen Taheri; Shayesteh Moghaddam, Narges; Haberland, Christoph; Dean, David; Miller, Michael J; Elahinia, Mohammad

2014-10-01

New metal alloys and metal fabrication strategies are likely to benefit future skeletal implant strategies. These metals and fabrication strategies were looked at from the point of view of standard-of-care implants for the mandible. These implants are used as part of the treatment for segmental resection due to oropharyngeal cancer, injury or correction of deformity due to pathology or congenital defect. The focus of this two-part review is the issues associated with the failure of existing mandibular implants that are due to mismatched material properties. Potential directions for future research are also studied. To mitigate these issues, the use of low-stiffness metallic alloys has been highlighted. To this end, the development, processing and biocompatibility of superelastic NiTi as well as resorbable magnesium-based alloys are discussed. Additionally, engineered porosity is reviewed as it can be an effective way of matching the stiffness of an implant with the surrounding tissue. These porosities and the overall geometry of the implant can be optimized for strain transduction and with a tailored stiffness profile. Rendering patient-specific, site-specific, morphology-specific and function-specific implants can now be achieved using these and other metals with bone-like material properties by additive manufacturing. The biocompatibility of implants prepared from superelastic and resorbable alloys is also reviewed. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Listening to Brain Microcircuits for Interfacing With External World-Progress in Wireless Implantable Microelectronic Neuroengineering Devices: Experimental systems are described for electrical recording in the brain using multiple microelectrodes and short range implantable or wearable broadcasting units.

Science.gov (United States)

Nurmikko, Arto V; Donoghue, John P; Hochberg, Leigh R; Patterson, William R; Song, Yoon-Kyu; Bull, Christopher W; Borton, David A; Laiwalla, Farah; Park, Sunmee; Ming, Yin; Aceros, Juan

2010-01-01

Acquiring neural signals at high spatial and temporal resolution directly from brain microcircuits and decoding their activity to interpret commands and/or prior planning activity, such as motion of an arm or a leg, is a prime goal of modern neurotechnology. Its practical aims include assistive devices for subjects whose normal neural information pathways are not functioning due to physical damage or disease. On the fundamental side, researchers are striving to decipher the code of multiple neural microcircuits which collectively make up nature's amazing computing machine, the brain. By implanting biocompatible neural sensor probes directly into the brain, in the form of microelectrode arrays, it is now possible to extract information from interacting populations of neural cells with spatial and temporal resolution at the single cell level. With parallel advances in application of statistical and mathematical techniques tools for deciphering the neural code, extracted populations or correlated neurons, significant understanding has been achieved of those brain commands that control, e.g., the motion of an arm in a primate (monkey or a human subject). These developments are accelerating the work on neural prosthetics where brain derived signals may be employed to bypass, e.g., an injured spinal cord. One key element in achieving the goals for practical and versatile neural prostheses is the development of fully implantable wireless microelectronic "brain-interfaces" within the body, a point of special emphasis of this paper.

Anterior spinal cord syndrome of unknown etiology

OpenAIRE

Klakeel, Merrine; Thompson, Justin; Srinivasan, Rajashree; McDonald, Frank

2015-01-01

A spinal cord injury encompasses a physical insult to the spinal cord. In the case of anterior spinal cord syndrome, the insult is a vascular lesion at the anterior spinal artery. We present the cases of two 13-year-old boys with anterior spinal cord syndrome, along with a review of the anatomy and vasculature of the spinal cord and an explanation of how a lesion in the cord corresponds to anterior spinal cord syndrome.

Preparation of targets by ion implantation

International Nuclear Information System (INIS)

Santry, D.C.

1976-01-01

Various factors are described which are involved in target preparation by direct ion implantation and the limitations and pitfalls of the method are emphasized. Examples are given of experiments for which ion implanted targets are well suited. (author)

Damage accumulation in nitrogen implanted 6H-SiC: Dependence on the direction of ion incidence and on the ion fluence

International Nuclear Information System (INIS)

Zolnai, Z.; Ster, A.; Khanh, N. Q.; Battistig, G.; Lohner, T.; Gyulai, J.; Kotai, E.; Posselt, M.

2007-01-01

The influence of crystallographic orientation and ion fluence on the shape of damage distributions induced by 500 keV N + implantation at room temperature into 6H-SiC is investigated. The irradiation was performed at different tilt angles between 0 degree sign and 4 degree sign with respect to the crystallographic axis in order to consider the whole range of beam alignment from channeling to random conditions. The applied implantation fluence range was 2.5x10 14 -3x10 15 cm -2 . A special analytical method, 3.55 MeV 4 He + ion backscattering analysis in combination with channeling technique (BS/C), was employed to measure the disorder accumulation simultaneously in the Si and C sublattices of SiC with good depth resolution. For correct energy to depth conversion in the BS/C spectra, the average electronic energy loss per analyzing He ion for the axial channeling direction was determined. It was found that the tilt angle of nitrogen implantation has strong influence on the shape of the induced disorder profiles. Significantly lower disorder was found for channeling than for random irradiation. Computer simulation of the measured BS/C spectra showed the presence of a simple defect structure in weakly damaged samples and suggested the formation of a complex disorder state for higher disorder levels. Full-cascade atomistic computer simulation of the ion implantation process was performed to explain the differences in disorder accumulation on the Si and C sublattices. The damage buildup mechanism was interpreted with the direct-impact, defect-stimulated amorphization model in order to understand damage formation and to describe the composition of structural disorder versus the ion fluence and the implantation tilt angle

Controlling selective stimulations below a spinal cord hemisection using brain recordings with a neural interface system approach

Science.gov (United States)

Panetsos, Fivos; Sanchez-Jimenez, Abel; Torets, Carlos; Largo, Carla; Micera, Silvestro

2011-08-01

In this work we address the use of realtime cortical recordings for the generation of coherent, reliable and robust motor activity in spinal-lesioned animals through selective intraspinal microstimulation (ISMS). The spinal cord of adult rats was hemisectioned and groups of multielectrodes were implanted in both the central nervous system (CNS) and the spinal cord below the lesion level to establish a neural system interface (NSI). To test the reliability of this new NSI connection, highly repeatable neural responses recorded from the CNS were used as a pattern generator of an open-loop control strategy for selective ISMS of the spinal motoneurons. Our experimental procedure avoided the spontaneous non-controlled and non-repeatable neural activity that could have generated spurious ISMS and the consequent undesired muscle contractions. Combinations of complex CNS patterns generated precisely coordinated, reliable and robust motor actions.

Spinal cord injury with central cord syndrome from surfing.

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Steinfeld, Yaniv; Keren, Yaniv; Haddad, Elias

2018-01-01

Central cord syndrome (CCS) is an injury to the center of the spinal cord. It is well known as a hyperextension injury, but it has never been described as a surfing injury. Our report describes this injury in detail. A 35-year-old male novice surfer presented to the emergency department with acute tetraplegia following falling off his surfboard and hitting sea floor at a shallow beach break. He was rescued by a fellow surfer while floating in the sea and unable to raise his head above sea level. Upon arrival at the hospital, tetraplegia and sensory deficits were noted. Radiological investigations showed advanced spinal stenosis at C4-6 levels. T2 magnetic resonance imaging (MRI) demonstrated myelopathy at C5-C6 level. He was diagnosed as having central cord syndrome, treated conservatively, and regained near full neurologic recovery after a month of rehabilitation. Unique sport activities lead to unique injuries. It is important to accurately describe these injuries in order to create protective measures against them. Neurologic injuries in surfers are uncommon. With low-energy trauma, surfer's myelopathy is still the most common diagnosis, but central cord syndrome should be in the differential diagnosis.

Secondary damage in the spinal cord after motor cortex injury in rats.

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Weishaupt, Nina; Silasi, Gergely; Colbourne, Frederick; Fouad, Karim

2010-08-01

When neurons within the motor cortex are fatally injured, their axons, many of which project into the spinal cord, undergo wallerian degeneration. Pathological processes occurring downstream of the cortical damage have not been extensively studied. We created a focal forelimb motor cortex injury in rats and found that axons from cell bodies located in the hindlimb motor cortex (spared by the cortical injury) become secondarily damaged in the spinal cord. To assess axonal degeneration in the spinal cord, we quantified silver staining in the corticospinal tract (CST) at 1 week and 4 weeks after the injury. We found a significant increase in silver deposition at the thoracic spinal cord level at 4 weeks compared to 1 week post-injury. At both time points, no degenerating neurons could be found in the hindlimb motor cortex. In a separate experiment, we showed that direct injury of neurons within the hindlimb motor cortex caused marked silver deposition in the thoracic CST at 1 week post-injury, and declined thereafter. Therefore, delayed axonal degeneration in the thoracic spinal cord after a focal forelimb motor cortex injury is indicative of secondary damage at the spinal cord level. Furthermore, immunolabeling of spinal cord sections showed that a local inflammatory response dominated by partially activated Iba-1-positive microglia is mounted in the CST, a viable mechanism to cause the observed secondary degeneration of fibers. In conclusion, we demonstrate that following motor cortex injury, wallerian degeneration of axons in the spinal cord leads to secondary damage, which is likely mediated by inflammatory processes.

Optimal method for collection of umbilical cord blood: an Egyptian trial for a public cord blood bank.

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Bassiouny, M R; El-Chennawi, F; Mansour, A K; Yahia, S; Darwish, A

2015-06-01

Umbilical cord blood (UCB) contains stem cells and can be used as an alternative to bone marrow transplantation. Engraftment is dependent on the total nucleated cell (TNC) and CD34+ cell counts of the cord blood units. This study was designed to evaluate the effect of the method of collection of the UCB on the yield of the cord blood units. Informed consent was obtained from 100 eligible mothers for donation of cord blood. Both in utero and ex utero methods were used for collection. The cord blood volume was measured. The TNC and the CD34+ cell counts were enumerated. We have found that in utero collection gave significantly larger volumes of cord blood and higher TNC counts than ex utero collection. There was no significant difference between both methods regarding the CD34+ cell counts. This study revealed a significant correlation between the volume of the collected cord blood and both TNC and CD34+ cell counts. It is better to collect cord blood in utero before placental delivery to optimize the quality of the cord blood unit. © 2015 AABB.

Induced hemocompatibility and bone formation as biological scaffold for cell therapy implant

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Keng-Liang Ou

2016-06-01

Full Text Available Although stem cells can become almost any type of specialized cell in the human body and may have the potential to generate replacement cells for tissues and organs, the transplantation of these cells are hindered by immune rejection and teratoma formation. However, scientists have found a promising solution for these problems-they have discovered the ability to isolate stem cells from a patient’s umbilical cord blood or bone marrow. Even more recently, small stem cells, such as spore-like stem cells, Blastomere-Like Stem Cells (BLSCs, and Very-Small Embryonic-Like stem cells (VSELs isolated directly from the peripheral blood have beeninvestigated as a novel approach to stem cell therapy as they can be isolated directly from the peripheral blood. A newly-discovered population of multipotent stem cells in this class has been dubbed StemBios (SB cells. The potential therapeutic uses of such stem cells have been explored in many ways, one of which includes dental remodeling and construction. Using adult stem cells, scientists have engineered and cultivated teeth in mice that may one day be used for human implantation.It follows that such regeneration may be possible, to a certain degree, in human patients as well. This idea leads to the present study on the effect of SB cell therapy on early osseointegrationof dental implants. Titanium (Ti dental implants have been proven to be a reliable and predictable treatment for restoration of edentulous regions. The osseointegration process can be described in two stages: primary stability (mechanical stability and secondary stability (biological stability. The mechanical stabilization of the implant reflects the interaction between the bone density and the features of the implant designs and can be determined after implant insertion. Alternatively,the biological stabilization of the implant is a physiologic healing process. It is couple to the biological interaction between the external surface of the

Direct recordings from the auditory cortex in a cochlear implant user.

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Nourski, Kirill V; Etler, Christine P; Brugge, John F; Oya, Hiroyuki; Kawasaki, Hiroto; Reale, Richard A; Abbas, Paul J; Brown, Carolyn J; Howard, Matthew A

2013-06-01

Electrical stimulation of the auditory nerve with a cochlear implant (CI) is the method of choice for treatment of severe-to-profound hearing loss. Understanding how the human auditory cortex responds to CI stimulation is important for advances in stimulation paradigms and rehabilitation strategies. In this study, auditory cortical responses to CI stimulation were recorded intracranially in a neurosurgical patient to examine directly the functional organization of the auditory cortex and compare the findings with those obtained in normal-hearing subjects. The subject was a bilateral CI user with a 20-year history of deafness and refractory epilepsy. As part of the epilepsy treatment, a subdural grid electrode was implanted over the left temporal lobe. Pure tones, click trains, sinusoidal amplitude-modulated noise, and speech were presented via the auxiliary input of the right CI speech processor. Additional experiments were conducted with bilateral CI stimulation. Auditory event-related changes in cortical activity, characterized by the averaged evoked potential and event-related band power, were localized to posterolateral superior temporal gyrus. Responses were stable across recording sessions and were abolished under general anesthesia. Response latency decreased and magnitude increased with increasing stimulus level. More apical intracochlear stimulation yielded the largest responses. Cortical evoked potentials were phase-locked to the temporal modulations of periodic stimuli and speech utterances. Bilateral electrical stimulation resulted in minimal artifact contamination. This study demonstrates the feasibility of intracranial electrophysiological recordings of responses to CI stimulation in a human subject, shows that cortical response properties may be similar to those obtained in normal-hearing individuals, and provides a basis for future comparisons with extracranial recordings.

Direct Conversion of Human Umbilical Cord Blood into Induced Neural Stem Cells with SOX2 and HMGA2.

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Kim, Jae-Jun; Shin, Ji-Hee; Yu, Kyung-Rok; Lee, Byung-Chul; Kang, Insung; Lee, Jin Young; Kim, Da-Hyun; Seo, Yoojin; Kim, Hyung-Sik; Choi, Soon Won; Kang, Kyung-Sun

2017-11-30

Recent advances have shown the direct reprogramming of mouse and human fibroblasts into induced neural stem cells (iNSCs) without passing through an intermediate pluripotent state. Thus, direct reprogramming strategy possibly provides a safe and homogeneous cellular platform. However, the applications of iNSCs for regenerative medicine are limited by the restricted availability of cell sources. Human umbilical cord blood (hUCB) cells hold great potential in that immunotyped hUCB units can be immediately obtained from public banks. Moreover, hUCB samples do not require invasive procedures during collection or an extensive culture period prior to reprogramming. We recently reported that somatic cells can be directly converted into iNSCs with high efficiency and a short turnaround time. Here, we describe the detailed method for the generation of iNSCs derived from hUCB (hUCB iNSCs) using the lineage-specific transcription factors SOX2 and HMGA2. The protocol for deriving iNSC-like colonies takes 1∼2 weeks and establishment of homogenous hUCB iNSCs takes additional 2 weeks. Established hUCB iNSCs are clonally expandable and multipotent producing neurons and glia. Our study provides an accessible method for generating hUCB iNSCs, contributing development of in vitro neuropathological model systems.

Combining neurotrophin-transduced schwann cells and rolipram to promote functional recovery from subacute spinal cord injury.

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Flora, Govinder; Joseph, Gravil; Patel, Samik; Singh, Amanpreet; Bleicher, Drew; Barakat, David J; Louro, Jack; Fenton, Stephanie; Garg, Maneesh; Bunge, Mary Bartlett; Pearse, Damien D

2013-01-01

Following spinal cord injury (SCI), both an inhibitory environment and lack of intrinsic growth capacity impede axonal regeneration. In a previous study, prevention of cyclic adenosine monophosphate (AMP) hydrolysis by the phosphodiesterase-4 inhibitor rolipram, in combination with Schwann cell (SC) grafts, promoted significant supraspinal and proprioceptive fiber growth and/or sparing and improved locomotion. In another study, transplanted SCs transduced to generate a bifunctional neurotrophin (D15A) led to significant increases in graft SCs and axons, including supraspinal and myelinated axons. Here we studied the growth and myelination of local and supraspinal axons and functional outcome following the combination of rolipram administration and neurotrophin-transduced SC implantation after SCI. Rolipram was administered subcutaneously for 4 weeks immediately after contusion at vertebral T8 (25.0-mm weight drop, MASCIS impactor). GFP or GFP-D15A-transduced SCs were injected into the injury epicenter 1 week after SCI. GFP-D15A SC grafts and GFP SC grafts with rolipram contained significantly more serotonergic fibers compared to GFP SCs. SC myelinated axons were increased significantly in GFP SC with rolipram-treated animals compared to animals receiving SCI alone. Rolipram administered with either GFP or GFP-D15A SCs significantly increased numbers of brain stem-derived axons below the lesion/implant area and improved hindlimb function. Compared to the single treatments, the combination led to the largest SC grafts, the highest numbers of serotonergic fibers in the grafts, and increased numbers of axons from the reticular formation below the lesion/implant area and provided the greatest improvement in hindlimb function. These findings demonstrate the therapeutic potential for a combination therapy involving the maintenance of cyclic AMP levels and neurotrophin-transduced SCs to repair the subacutely injured spinal cord.

Improved axonal regeneration of transected spinal cord mediated by multichannel collagen conduits functionalized with neurotrophin-3 gene.

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Yao, L; Daly, W; Newland, B; Yao, S; Wang, W; Chen, B K K; Madigan, N; Windebank, A; Pandit, A

2013-12-01

Functionalized biomaterial scaffolds targeted at improving axonal regeneration by enhancing guided axonal growth provide a promising approach for the repair of spinal cord injury. Collagen neural conduits provide structural guidance for neural tissue regeneration, and in this study it is shown that these conduits can also act as a reservoir for sustained gene delivery. Either a G-luciferase marker gene or a neurotrophin-3-encoding gene, complexed to a non-viral, cyclized, PEGylated transfection vector, was loaded within a multichannel collagen conduit. The complexed genes were then released in a controlled fashion using a dual release system both in vitro and in vivo. For evaluation of their biological performance, the loaded conduits were implanted into the completely transected rat thoracic spinal cord (T8-T10). Aligned axon regeneration through the channels of conduits was observed one month post-surgery. The conduits delivering neurotrophin-3 polyplexes resulted in significantly increased neurotrophin-3 levels in the surrounding tissue and a statistically higher number of regenerated axons versus the control conduits (P<0.05). This study suggests that collagen neural conduits delivering a highly effective non-viral therapeutic gene may hold promise for repair of the injured spinal cord.

Osteogenesis and Morphology of the Peri-Implant Bone Facing Dental Implants

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Marco Franchi

2004-01-01

Full Text Available This study investigated the influence of different implant surfaces on peri-implant osteogenesis and implant face morphology of peri-implant tissues during the early (2 weeks and complete healing period (3 months. Thirty endosseous titanium implants (conic screws with differently treated surfaces (smooth titanium = SS, titanium plasma sprayed = TPS, sand-blasted zirconium oxide = Zr-SLA were implanted in femur and tibiae diaphyses of two mongrel sheep. Histological sections of the implants and surrounding tissues obtained by sawing and grinding techniques were observed under light microscopy (LM. The peri-implant tissues of other samples were mechanically detached from the corresponding implants to be processed for SEM observation. Two weeks after implantation, we observed osteogenesis (new bone trabeculae around all implant surfaces only where a gap was present at the host bone-metal interface. No evident bone deposition was detectable where threads of the screws were in direct contact with the compact host bone. Distance osteogenesis predominated in SS implants, while around rough surfaces (TPS and Zr-SLA, both distance and contact osteogenesis were present. At SEM analysis 2 weeks after implantation, the implant face of SS peri-implant tissue showed few, thin, newly formed, bone trabeculae immersed in large, loose, marrow tissue with blood vessels. Around the TPS screws, the implant face of the peri-implant tissue was rather irregular because of the rougher metal surface. Zr-SLA screws showed more numerous, newly formed bone trabeculae crossing marrow spaces and also needle-like crystals in bone nodules indicating an active mineralising process. After 3 months, all the screws appeared osseointegrated, being almost completely covered by a compact, mature, newly formed bone. However, some marrow spaces rich in blood vessels and undifferentiated cells were in contact with the metal surface. By SEM analysis, the implant face of the peri-implant

Identification of ghost artifact using texture analysis in pediatric spinal cord diffusion tensor images.

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Alizadeh, Mahdi; Conklin, Chris J; Middleton, Devon M; Shah, Pallav; Saksena, Sona; Krisa, Laura; Finsterbusch, Jürgen; Faro, Scott H; Mulcahey, M J; Mohamed, Feroze B

2018-04-01

Ghost artifacts are a major contributor to degradation of spinal cord diffusion tensor images. A multi-stage post-processing pipeline was designed, implemented and validated to automatically remove ghost artifacts arising from reduced field of view diffusion tensor imaging (DTI) of the pediatric spinal cord. A total of 12 pediatric subjects including 7 healthy subjects (mean age=11.34years) with no evidence of spinal cord injury or pathology and 5 patients (mean age=10.96years) with cervical spinal cord injury were studied. Ghost/true cords, labeled as region of interests (ROIs), in non-diffusion weighted b0 images were segmented automatically using mathematical morphological processing. Initially, 21 texture features were extracted from each segmented ROI including 5 first-order features based on the histogram of the image (mean, variance, skewness, kurtosis and entropy) and 16s-order feature vector elements, incorporating four statistical measures (contrast, correlation, homogeneity and energy) calculated from co-occurrence matrices in directions of 0°, 45°, 90° and 135°. Next, ten features with a high value of mutual information (MI) relative to the pre-defined target class and within the features were selected as final features which were input to a trained classifier (adaptive neuro-fuzzy interface system) to separate the true cord from the ghost cord. The implemented pipeline was successfully able to separate the ghost artifacts from true cord structures. The results obtained from the classifier showed a sensitivity of 91%, specificity of 79%, and accuracy of 84% in separating the true cord from ghost artifacts. The results show that the proposed method is promising for the automatic detection of ghost cords present in DTI images of the spinal cord. This step is crucial towards development of accurate, automatic DTI spinal cord post processing pipelines. Copyright © 2017 Elsevier Inc. All rights reserved.

Sparing of descending axons rescues interneuron plasticity in the lumbar cord to allow adaptive learning after thoracic spinal cord injury

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Christopher Nelson Hansen

2016-03-01

Full Text Available This study evaluated the role of spared axons on structural and behavioral neuroplasticity in the lumbar enlargement after a thoracic spinal cord injury (SCI. Previous work has demonstrated that recovery in the presence of spared axons after an incomplete lesion increases behavioral output after a subsequent complete spinal cord transection (TX. This suggests that spared axons direct adaptive changes in below-level neuronal networks of the lumbar cord. In response to spared fibers, we postulate that lumbar neuron networks support behavioral gains by preventing aberrant plasticity. As such, the present study measured histological and functional changes in the isolated lumbar cord after complete TX or incomplete contusion (SCI. To measure functional plasticity in the lumbar cord, we used an established instrumental learning paradigm. In this paradigm, neural circuits within isolated lumbar segments demonstrate learning by an increase in flexion duration that reduces exposure to a noxious leg shock. We employed this model using a proof-of-principle design to evaluate the role of sparing on lumbar learning and plasticity early (7 days or late (42 days after midthoracic SCI in a rodent model. Early after SCI or TX at 7d, spinal learning was unattainable regardless of whether the animal recovered with or without axonal substrate. Failed learning occurred alongside measures of cell soma atrophy and aberrant dendritic spine expression within interneuron populations responsible for sensorimotor integration and learning. Alternatively, exposure of the lumbar cord to a small amount of spared axons for 6 weeks produced near-normal learning late after SCI. This coincided with greater cell soma volume and fewer aberrant dendritic spines on interneurons. Thus, an opportunity to influence activity-based learning in locomotor networks depends on spared axons limiting maladaptive plasticity. Together, this work identifies a time dependent interaction between

Arterial Blood Supply to the Spinal Cord in Animal Models of Spinal Cord Injury. A Review.

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Mazensky, David; Flesarova, Slavka; Sulla, Igor

2017-12-01

Animal models are used to examine the results of experimental spinal cord injury. Alterations in spinal cord blood supply caused by complex spinal cord injuries contribute significantly to the diversity and severity of the spinal cord damage, particularly ischemic changes. However, the literature has not completely clarified our knowledge of anatomy of the complex three-dimensional arterial system of the spinal cord in experimental animals, which can impede the translation of experimental results to human clinical applications. As the literary sources dealing with the spinal cord arterial blood supply in experimental animals are limited and scattered, the authors performed a review of the anatomy of the arterial blood supply to the spinal cord in several experimental animals, including pigs, dogs, cats, rabbits, guinea pigs, rats, and mice and created a coherent format discussing the interspecies differences. This provides researchers with a valuable tool for the selection of the most suitable animal model for their experiments in the study of spinal cord ischemia and provides clinicians with a basis for the appropriate translation of research work to their clinical applications. Anat Rec, 300:2091-2106, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Micro-cutting of silicon implanted with hydrogen and post-implantation thermal treatment

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Jelenković, Emil V.; To, Suet; Sundaravel, B.; Xiao, Gaobo; Huang, Hu

2016-07-01

It was reported that non-amorphizing implantation by hydrogen has a potential in improving silicon machining. Post-implantation high-temperature treatment will affect implantation-induced damage, which can have impact on silicon machining. In this article, a relation of a thermal annealing of hydrogen implanted in silicon to micro-cutting experiment is investigated. Hydrogen ions were implanted into 4″ silicon wafers with 175 keV, 150 keV, 125 keV and doses of 2 × 1016 cm-2, 2 × 1016 cm-2 and 3 × 1016 cm-2, respectively. In this way, low hydrogen atom-low defect concentration was created in the region less than ~0.8 μm deep and high hydrogen atom-high defect concentration was obtained at silicon depth of ~0.8-1.5 μm. The post-implantation annealing was carried out at 300 and 400 °C in nitrogen for 1 h. Physical and electrical properties of implanted and annealed samples were characterized by secondary ion mass spectroscopy (SIMS), X-ray diffraction (XRD), Rutherford backscattering (RBS) and nanoindentation. Plunge cutting experiment was carried out in and silicon crystal direction. The critical depth of cut and cutting force were monitored and found to be influenced by the annealing. The limits of hydrogen implantation annealing contribution to the cutting characteristics of silicon are discussed in light of implantation process and redistribution of hydrogen and defects generation during annealing process.

Two-stage implant systems.

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Fritz, M E

1999-06-01

Since the advent of osseointegration approximately 20 years ago, there has been a great deal of scientific data developed on two-stage integrated implant systems. Although these implants were originally designed primarily for fixed prostheses in the mandibular arch, they have been used in partially dentate patients, in patients needing overdentures, and in single-tooth restorations. In addition, this implant system has been placed in extraction sites, in bone-grafted areas, and in maxillary sinus elevations. Often, the documentation of these procedures has lagged. In addition, most of the reports use survival criteria to describe results, often providing overly optimistic data. It can be said that the literature describes a true adhesion of the epithelium to the implant similar to adhesion to teeth, that two-stage implants appear to have direct contact somewhere between 50% and 70% of the implant surface, that the microbial flora of the two-stage implant system closely resembles that of the natural tooth, and that the microbiology of periodontitis appears to be closely related to peri-implantitis. In evaluations of the data from implant placement in all of the above-noted situations by means of meta-analysis, it appears that there is a strong case that two-stage dental implants are successful, usually showing a confidence interval of over 90%. It also appears that the mandibular implants are more successful than maxillary implants. Studies also show that overdenture therapy is valid, and that single-tooth implants and implants placed in partially dentate mouths have a success rate that is quite good, although not quite as high as in the fully edentulous dentition. It would also appear that the potential causes of failure in the two-stage dental implant systems are peri-implantitis, placement of implants in poor-quality bone, and improper loading of implants. There are now data addressing modifications of the implant surface to alter the percentage of

SPINAL CORD- A CADAVERIC STUDY

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Vijayamma K. N

2018-01-01

Full Text Available BACKGROUND Spinal cord is situated within the vertebral canal extending from the lower end of the medulla oblongata at the upper border of first cervical vertebra. In early foetal life, it extends throughout the length of the vertebral canal, and at the time of birth, it reaches the level of third lumbar vertebra. In adult, it ends at the lower border of first lumbar vertebra and thereafter continued as filum terminale, which gets attached to tip of coccyx. Spinal cord is covered by three protective membranes called spinal meninges, diameter, arachnoid and pia mater. The diameter and arachnoid mater extent up to second sacral vertebra and the pia mater forms filum terminale and extend at the tip of coccyx. MATERIALS AND METHODS Forty spinal cord cadaveric specimen were studied by dissection method after exposing the vertebral canal. The roots of spinal nerve were sectioned on both sides and the cord is released along with its coverings. The dura and arachnoid mater were incised longitudinally and the subarachnoid space, blood vessels, nerve roots, ligament denticulata, cervical and lumbar enlargements were observed. The blood vessels including radicular arteries were also studied photographed. RESULTS The spinal cord is a highly vascular structure situated within the vertebral canal, covered by diameter, arachnoid mater and pia mater. Spinal dura is thicker anteriorly than posteriorly. The pia mater forms linea splendens, which extend along the whole length of the cord in front of the anterior median fissure. The average length of the cord is 38 cm. The length and breadth of cervical enlargement was more compared to lumbar enlargement. The number of rootlets in both dorsal and ventral roots accounts more in cervical compared to other regions of the cord. The ligament denticulata is a thin transparent bands of pia mater attached on either sides of the cord between the dorsal and ventral roots of spinal nerves. The tooth like extensions are well

Transplanted Umbilical Cord Mesenchymal Stem Cells Modify the In Vivo Microenvironment Enhancing Angiogenesis and Leading to Bone Regeneration

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Todeschi, Maria Rosa; El Backly, Rania; Capelli, Chiara; Daga, Antonio; Patrone, Eugenio; Introna, Martino; Cancedda, Ranieri

2015-01-01

Umbilical cord mesenchymal stem cells (UC-MSCs) show properties similar to bone marrow mesenchymal stem cells (BM-MSCs), although controversial data exist regarding their osteogenic potential. We prepared clinical-grade UC-MSCs from Wharton's Jelly and we investigated if UC-MSCs could be used as substitutes for BM-MSCs in muscoloskeletal regeneration as a more readily available and functional source of MSCs. UC-MSCs were loaded onto scaffolds and implanted subcutaneously (ectopically) and in critical-sized calvarial defects (orthotopically) in mice. For live cell-tracking experiments, UC-MSCs were first transduced with the luciferase gene. Angiogenic properties of UC-MSCs were tested using the mouse metatarsal angiogenesis assay. Cell secretomes were screened for the presence of various cytokines using an array assay. Analysis of implanted scaffolds showed that UC-MSCs, contrary to BM-MSCs, remained detectable in the implants for 3 weeks at most and did not induce bone formation in an ectopic location. Instead, they induced a significant increase of blood vessel ingrowth. In agreement with these observations, UC-MSC-conditioned medium presented a distinct and stronger proinflammatory/chemotactic cytokine profile than BM-MSCs and a significantly enhanced angiogenic activity. When UC-MSCs were orthotopically transplanted in a calvarial defect, they promoted increased bone formation as well as BM-MSCs. However, at variance with BM-MSCs, the new bone was deposited through the activity of stimulated host cells, highlighting the importance of the microenvironment on determining cell commitment and response. Therefore, we propose, as therapy for bone lesions, the use of allogeneic UC-MSCs by not depositing bone matrix directly, but acting through the activation of endogenous repair mechanisms. PMID:25685989

Successful Reinnervation of the Diaphragm After Intercostal to Phrenic Nerve Neurotization in Patients With High Spinal Cord Injury.

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Nandra, Kulvir S; Harari, Martin; Price, Thea P; Greaney, Patrick J; Weinstein, Michael S

2017-08-01

Our objective in this study was to extend diaphragmatic pacing therapy to include paraplegic patients with high cervical spinal cord injuries between C3 and C5. Diaphragmatic pacing has been used in patients experiencing ventilator-dependent respiratory failure due to spinal cord injury as a means to reduce or eliminate the need for mechanical ventilation. However, this technique relies on intact phrenic nerve function. Recently, phrenic nerve reconstruction with intercostal nerve grafting has expanded the indications for diaphragmatic pacing. Our study aimed to evaluate early outcomes and efficacy of intercostal nerve transfer in diaphragmatic pacing. Four ventilator-dependent patients with high cervical spinal cord injuries were selected for this study. Each patient demonstrated absence of phrenic nerve function via external neck stimulation and laparoscopic diaphragm mapping. Each patient underwent intercostal to phrenic nerve grafting with implantation of a phrenic nerve pacer. The patients were followed, and ventilator dependence was reassessed at 1 year postoperatively. Our primary outcome was measured by the amount of time our patients tolerated off the ventilator per day. We found that all 4 patients have tolerated paced breathing independent of mechanical ventilation, with 1 patient achieving 24 hours of tracheostomy collar. From this study, intercostal to phrenic nerve transfer seems to be a promising approach in reducing or eliminating ventilator support in patients with C3 to C5 high spinal cord injury.

Optogenetics of the Spinal Cord: Use of Channelrhodopsin Proteins for Interrogation of Spinal Cord Circuits.

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Rahman, Habibur; Nam, Youngpyo; Kim, Jae-Hong; Lee, Won-Ha; Suk, Kyoungho

2017-12-29

Spinal cord circuits play a key role in receiving and transmitting somatosensory information from the body and the brain. They also contribute to the timing and coordination of complex patterns of movement. Under disease conditions, such as spinal cord injury and neuropathic pain, spinal cord circuits receive pain signals from peripheral nerves, and are involved in pain development via neurotransmitters and inflammatory mediators released from neurons and glial cells. Despite the importance of spinal cord circuits in sensory and motor functions, many questions remain regarding the relationship between activation of specific cells and behavioral responses. Optogenetics offers the possibility of understanding the complex cellular activity and mechanisms of spinal cord circuits, as well as having therapeutic potential for addressing spinal cord-related disorders. In this review, we discuss recent findings in optogenetic research employing the channelrhodopsin protein to assess the function of specific neurons and glia in spinal cord circuits ex vivo and in vivo. We also explore the possibilities and challenges of employing optogenetics technology in future therapeutic strategies for the treatment of spinal disorders. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

A New Trend in Recording Subgingival Tissue around an Implant While Making a Direct Abutment Impression

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Suryakant C. Deogade

2014-01-01

Full Text Available A successful implant-supported restoration must provide adequate function and esthetics. Osseointegrated implants have given an alternative choice for patients who have lost their teeth. Most commonly encountered problems while doing a transfer from patient to the master cast in restoring implant-supported crowns are an uneven distribution of occlusal loads and undue torquing forces on the various elements of implant. This is caused due to poor fit of frameworks connected to implant, which further leads to marginal bone loss, loosening of screws, fatigue fracture of implant components, and ultimately implant failure. This paper presents a simplified and easy solution to overcome such problems by introducing an innovative gingival retraction system for restoring implant-supported crowns to achieve superior and predictable long-term outcomes.

Spinal Cord Dysfunction (SCD)

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Department of Veterans Affairs — The Spinal Cord Dysfunction (SCD) module supports the maintenance of local and national registries for the tracking of patients with spinal cord injury and disease...

Restoring voluntary control of locomotion after paralyzing spinal cord injury

NARCIS (Netherlands)

van den Brand, Rubia; Heutschi, Janine; Barraud, Quentin; DiGiovanna, Jack; Bartholdi, Kay; Huerlimann, Michèle; Friedli, Lucia; Vollenweider, Isabel; Moraud, Eduardo Martin; Duis, Simone; Dominici, Nadia; Micera, Silvestro; Musienko, Pavel; Courtine, Grégoire

2012-01-01

Half of human spinal cord injuries lead to chronic paralysis. Here, we introduce an electrochemical neuroprosthesis and a robotic postural interface designed to encourage supraspinally mediated movements in rats with paralyzing lesions. Despite the interruption of direct supraspinal pathways, the

Transcatheter aortic valve implantation of the direct flow medical aortic valve with minimal or no contrast

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Latib, Azeem, E-mail: alatib@gmail.com [Interventional Cardiology Unit, San Raffaele Scientific Institute and EMO-GVM Centro Cuore Columbus, Milan (Italy); Maisano, Francesco; Colombo, Antonio [Interventional Cardiology Unit, San Raffaele Scientific Institute and EMO-GVM Centro Cuore Columbus, Milan (Italy); Klugmann, Silvio [Azienda Ospedaliera Niguarda Ca Granda, Piazza Ospedale Maggiore 3, Milan (Italy); Low, Reginald; Smith, Thomas [University of California Davis, Davis, CA 95616 (United States); Davidson, Charles [Northwestern Memorial Hospital, Chicago, IL 60611 (United States); Harreld, John H. [Clinical Imaging Analytics, Guerneville, CA (United States); Bruschi, Giuseppe; DeMarco, Federico [Azienda Ospedaliera Niguarda Ca Granda, Piazza Ospedale Maggiore 3, Milan (Italy)

2014-06-15

The 18F Direct Flow Medical (DFM) THV has conformable sealing rings, which minimizes aortic regurgitation and permits full hemodynamic assessment of valve performance prior to permanent implantation. During the DISCOVER trial, three patients who were at risk for receiving contrast media, two due to severe CKD and one due to a recent hyperthyroid reaction to contrast, underwent DFM implantation under fluoroscopic and transesophageal guidance without aortography during either positioning or to confirm the final position. Valve positioning was based on the optimal angiographic projection as calculated by the pre-procedural multislice CT scan. Precise optimization of valve position was performed to minimize transvalve gradient and aortic regurgitation. Prior to final implantation, transvalve hemodynamics were assessed invasively and by TEE. The post-procedure mean gradients were 7, 10, 11 mm Hg. The final AVA by echo was 1.70, 1.40 and 1.68 cm{sup 2}. Total aortic regurgitation post-procedure was none or trace in all three patients. Total positioning and assessment of valve performance time was 4, 6, and 12 minutes. Contrast was only used to confirm successful percutaneous closure of the femoral access site. The total contrast dose was 5, 8, 12 cc. Baseline eGFR and creatinine was 28, 22, 74 mL/min/1.73 m{sup 2} and 2.35, 2.98, and 1.03 mg/dL, respectively. Renal function was unchanged post-procedure: eGFR = 25, 35, and 96 mL/min/1.73 m{sup 2} and creatinine = 2.58, 1.99, and 1.03 mg/dL, respectively. In conclusion, the DFM THV provides the ability to perform TAVI with minimal or no contrast. The precise and predictable implantation technique can be performed with fluoro and echo guidance.

Spinal cord swelling and candidiasis

International Nuclear Information System (INIS)

Ho, K.; Gronseth, G.; Aldrich, M.; Williams, A.

1982-01-01

Fusiform swelling of the spinal cord was noted myelographically in a patient with Hodgkin's disease. Autopsy revealed that the swelling was cauused by Candida infection of the spinal cord. It is suggested that fungal infection be included in the differential diagnosis of spinal cord swelling in the immunsupporessed cancer patient. (orig.)

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MR imaging and spinal cord injury

International Nuclear Information System (INIS)

Azar-Kia, B.; Fine, M.; Naheedy, M.; Elias, D.

1987-01-01

MR imaging has significantly improved diagnostic capability of spinal cord injuries. Other available diagnostic modalities such as plain films, myelography, CT, and post-CT myelography have failed to consistently show the secific evidence of spinal cord injuries and their true extent. The authors are presenting our experiences with MR imaging in spinal column injury. They have found MR imaging to be the procedure of choice for prognostic evaluation of spinal cord trauma. They are showing examples of recent and old spinal cord injury such as hematomyelia, myelomalacia, transection, spinal cord edema, and cavitation

Optical monitoring of spinal cord subcellular damage after acute spinal cord injury

Science.gov (United States)

Shadgan, Babak; Manouchehri, Neda; So, Kitty; Shortt, Katelyn; Fong, Allan; Streijger, Femke; Macnab, Andrew; Kwon, Brian K.

2018-02-01

Introduction: Sudden physical trauma to the spinal cord results in acute spinal cord injury (SCI), leading to spinal cord (SC) tissue destruction, acute inflammation, increased SC intraparenchymal pressure, and tissue ischemia, hypoxia, and cellular necrosis. The ability to monitor SC tissue viability at subcellular level, using a real-time noninvasive method, would be extremely valuable to clinicians for estimating acute SCI damage, and adjusting and monitoring treatment in the intensive care setting. This study examined the feasibility and sensitivity of a custommade near infrared spectroscopy (NIRS) sensor to monitor the oxidation state of SC mitochondrial cytochrome aa3 (CCO), which reflects the subcellular damage of SC tissue in an animal model of SCI. Methods: Six anesthetized Yorkshire pigs were studied using a custom-made multi-wavelength NIRS system with a miniaturized optical sensor applied directly on the surgically exposed SC at T9. The oxidation states of SC tissue hemoglobin and CCO were monitored before, during and after acute SCI, and during mean arterial pressure alterations. Results: Non-invasive NIRS monitoring reflected changes in SC tissue CCO, simultaneous but independent of changes in hemoglobin saturation following acute SCI. A consistent decrease in SC tissue CCO chromophore concentration (-1.98 +/- 2.1 ab, pElevation of mean arterial pressure can reduce SC tissue damage as suggested by different researchers and observed by significant increase in SC tissue CCO concentration (1.51 +/- 1.7 ab, p<0.05) in this study. Conclusions: This pilot study indicates that a novel miniaturized multi-wave NIRS sensor has the potential to monitor post-SCI changes of SC cytochrome aa3 oxygenation state in real time. Further development of this method may offer new options for improved SCI care.

Spinal cord swelling and candidiasis

Energy Technology Data Exchange (ETDEWEB)

Ho, K.; Gronseth, G.; Aldrich, M.; Williams, A.

1982-11-01

Fusiform swelling of the spinal cord was noted myelographically in a patient with Hodgkin's disease. Autopsy revealed that the swelling was caused by Candida infection of the spinal cord. It is suggested that fungal infection be included in the differential diagnosis of spinal cord swelling in the immunosuppressed cancer patient.

Future directions of failed implantation and recurrent miscarriage research

DEFF Research Database (Denmark)

Christiansen, Ole B; Nielsen, Henriette Svarre; Kolte, Astrid M

2006-01-01

Recurrent implantation failure is today the major reason for women completing several IVF/intracytoplasmic sperm injection attempts without having achieved a child, and is probably also the explanation for many cases of unexplained infertility. Most causes of recurrent miscarriage are still poorl...

Spinal-cord swelling in acute multiple sclerosis

International Nuclear Information System (INIS)

Kikuchi, Seiji; Tashiro, Kunio; Naganuma, Mutsuo; Hida, Kazutoshi; Iwasaki, Yoshinobu; Abe, Hiroshi; Miyasaka, Kazuo

1986-01-01

Despite the frequent involvement of the spinal cord by multiple sclerosis, reports concerning neuroradiological findings regarding these lesions have been limited; most of them have demonstrated a normal or small spinal cord. Two cases of acute paraparesis showed evidence of spinal-cord swelling on myelography and CT myelography, initially suggesting the diagnosis of an intramedullary tumor. Spinal-cord swelling was demonstrated more clearly on CT myelography than on conventional myelography. The diagnosis of multiple sclerosis was made with the aid of the CSF findings, the clinical course, and the contracting-cord sign. The ''contracting-cord sign'' means the diminution of the spinal-cord diameter in the chronic stage. Since acute multiple sclerosis may produce spinal-cord swelling simulating a tumor, careful investigations are necessary to avoid unwarranted surgical interventions. (author)

Focal Anterior Displacement of the Thoracic Spinal Cord without Evidence of Spinal Cord Herniation or an Intradural Mass

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Lee, Jong Yoon; Lee, Joon Woo; Lee, Guen Young; Kang, Heung Sik [Department of Radiology, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of)

2014-07-01

We report magnetic resonance imaging (MRI) findings on focal anterior displacement of the thoracic spinal cord in asymptomatic patients without a spinal cord herniation or intradural mass. We identified 12 patients (male:female = 6:6; mean age, 51.7; range, 15-83 years) between 2007 and 2011, with focal anterior displacement of the spinal cord and without evidence of an intradural mass or spinal cord herniation. Two radiologists retrospectively reviewed the MRI findings in consensus. An asymmetric spinal cord deformity with a focal dented appearance was seen on the posterior surface of the spinal cord in all patients, and it involved a length of 1 or 2 vertebral segments in the upper thoracic spine (thoracic vertebrae 1-6). Moreover, a focal widening of the posterior subarachnoid space was also observed in all cases. None of the patients had myelopathy symptoms, and they showed no focal T2-hyperintensity in the spinal cord with the exception of one patient. In addition, cerebrospinal fluid (CSF) flow artifacts were seen in the posterior subarachnoid space of the affected spinal cord level. Computed tomography myelography revealed preserved CSF flow in the two available patients. Focal anterior spinal cord indentation can be found in the upper thoracic level of asymptomatic patients without a spinal cord herniation or intradural mass.

Focal Anterior Displacement of the Thoracic Spinal Cord without Evidence of Spinal Cord Herniation or an Intradural Mass

International Nuclear Information System (INIS)

Lee, Jong Yoon; Lee, Joon Woo; Lee, Guen Young; Kang, Heung Sik

2014-01-01

We report magnetic resonance imaging (MRI) findings on focal anterior displacement of the thoracic spinal cord in asymptomatic patients without a spinal cord herniation or intradural mass. We identified 12 patients (male:female = 6:6; mean age, 51.7; range, 15-83 years) between 2007 and 2011, with focal anterior displacement of the spinal cord and without evidence of an intradural mass or spinal cord herniation. Two radiologists retrospectively reviewed the MRI findings in consensus. An asymmetric spinal cord deformity with a focal dented appearance was seen on the posterior surface of the spinal cord in all patients, and it involved a length of 1 or 2 vertebral segments in the upper thoracic spine (thoracic vertebrae 1-6). Moreover, a focal widening of the posterior subarachnoid space was also observed in all cases. None of the patients had myelopathy symptoms, and they showed no focal T2-hyperintensity in the spinal cord with the exception of one patient. In addition, cerebrospinal fluid (CSF) flow artifacts were seen in the posterior subarachnoid space of the affected spinal cord level. Computed tomography myelography revealed preserved CSF flow in the two available patients. Focal anterior spinal cord indentation can be found in the upper thoracic level of asymptomatic patients without a spinal cord herniation or intradural mass

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The effect of inter-implant distance on retention and resistance to dislodging forces for mandibular implant-tissue-supported overdentures.

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Farhad Tabatabaian

2014-10-01

Full Text Available The effect of inter-implant distance on retention and resistance of implant-tissue-supported overdentures is lacking in the literature. An in vitro study was performed to evaluate this effect for mandibular implant-tissue-supported overdentures retained by two ball attachments.An acrylic cast of an edentulous mandible was fabricated. Three pairs of implants were symmetrically placed at both sides of the midline. The inter-implant distance was 10, 25, and 35 millimeters in positions A, B and C, respectively. A framework simulating the overdenture was fabricated on the cast. Six attachment housings were placed within the overdenture. For each sample, two ball abutments were screwed onto the implant pairs and two pink nylon inserts were seated in their respective attachment housings. The samples were tested in three groups of 15 (A, B, and C. The testing machine applied tensile dislodging forces and peak loads were measured in three directions: vertical, oblique, and anterior-posterior. A one-way ANOVA followed by Tukey's HSD was used to determine groups that were significantly different. Tests were carried out at 0.05 level of significance.Peak loads for the anterior-posteriorly directed dislodging forces were significantly the highest for group C (P0.05.Inter-implant distance did not affect the vertical retention and oblique resistance of mandibular implant-tissue-supported overdentures; however, it affected anterior-posterior resistance.

Advances in regenerative therapies for spinal cord injury: a biomaterials approach

Directory of Open Access Journals (Sweden)

Magdalini Tsintou

2015-01-01

Full Text Available Spinal cord injury results in the permanent loss of function, causing enormous personal, social and economic problems. Even though neural regeneration has been proven to be a natural mechanism, central nervous system repair mechanisms are ineffective due to the imbalance of the inhibitory and excitatory factors implicated in neuroregeneration. Therefore, there is growing research interest on discovering a novel therapeutic strategy for effective spinal cord injury repair. To this direction, cell-based delivery strategies, biomolecule delivery strategies as well as scaffold-based therapeutic strategies have been developed with a tendency to seek for the answer to a combinatorial approach of all the above. Here we review the recent advances on regenerative/neural engineering therapies for spinal cord injury, aiming at providing an insight to the most promising repair strategies, in order to facilitate future research conduction.

Angular distributions of sputtered particles from lithium-implanted aluminium and copper crystals

International Nuclear Information System (INIS)

Johansen, A.; Johnson, E.; Sarholt-Kristensen, L.; Steenstrup, S.; Andersen, H.H.; Buhanov, V.M.; Chernysh, V.S.; Ivanov, I.N.; Minnebaev, K.F.

1991-01-01

The anisotropy of angular distributions of sputtered ions from lithium implanted aluminium and copper single crystals, measured by SIMS analysis, have been used to obtain information about the microstructure of the implanted layers. Sputtered Al + distributions from the {111} surface show three-fold symmetry with maximum intensity near the and directions respectively, while Li + distributions show maximum intensity only in the directions. From {100} crystals the Al + distributions have four-fold symmetry while there are no preferential ejection directions for the Li + ions. This agrees conceptually with the fact that the implanted layer contains the ordered Al 3 Li (δ') phase, which has earlier been observed by TEM analysis on implanted samples. In contrast, a similar study of Li + implanted copper crystals shows that the implanted lithium is randomly located. (orig.)

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Cord blood buffy coat DNA methylation is comparable to whole cord blood methylation.

Science.gov (United States)

Dou, John; Schmidt, Rebecca J; Benke, Kelly S; Newschaffer, Craig; Hertz-Picciotto, Irva; Croen, Lisa A; Iosif, Ana-Maria; LaSalle, Janine M; Fallin, M Daniele; Bakulski, Kelly M

2018-01-01

Cord blood DNA methylation is associated with numerous health outcomes and environmental exposures. Whole cord blood DNA reflects all nucleated blood cell types, while centrifuging whole blood separates red blood cells, generating a white blood cell buffy coat. Both sample types are used in DNA methylation studies. Cell types have unique methylation patterns and processing can impact cell distributions, which may influence comparability. We evaluated differences in cell composition and DNA methylation between cord blood buffy coat and whole cord blood samples. Cord blood DNA methylation was measured with the Infinium EPIC BeadChip (Illumina) in eight individuals, each contributing buffy coat and whole blood samples. We analyzed principal components (PC) of methylation, performed hierarchical clustering, and computed correlations of mean-centered methylation between pairs. We conducted moderated t-tests on single sites and estimated cell composition. DNA methylation PCs were associated with individual (P PC1 = 1.4 × 10 -9 ; P PC2 = 2.9 × 10 -5 ; P PC3 = 3.8 × 10 -5 ; P PC4 = 4.2 × 10 -6 ; P PC5 = 9.9 × 10 -13 , P PC6 = 1.3 × 10 -11 ) and not with sample type (P PC1-6 >0.7). Samples hierarchically clustered by individual. Pearson correlations of mean-centered methylation between paired samples ranged from r = 0.66 to r = 0.87. No individual site significantly differed between buffy coat and whole cord blood when adjusting for multiple comparisons (five sites had unadjusted Pcoat and whole cord blood are much lower than inter-individual variation, demonstrating that both sample preparation types can be analytically combined and compared.

Heterotopic ossification associated with myelopathy following cervical disc prosthesis implantation.

Science.gov (United States)

Wenger, Markus; Markwalder, Thomas-Marc

2016-04-01

This case report presents a 37-year-old man with clinical signs of myelopathy almost 9 years after implantation of a Bryan disc prosthesis (Medtronic Sofamor Danek, Memphis, TN, USA) for C5/C6 soft disc herniation. As demonstrated on MRI and CT scan, spinal cord compression was caused by bony spurs due to heterotopic ossification posterior to the still moving prosthesis. The device, as well as the ectopic bone deposits, had to be removed because of myelopathy and its imminent aggravation. Conversion to anterior spondylodesis was performed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Experimental spinal cord trauma: a review of mechanically induced spinal cord injury in rat models.

Science.gov (United States)

Abdullahi, Dauda; Annuar, Azlina Ahmad; Mohamad, Masro; Aziz, Izzuddin; Sanusi, Junedah

2017-01-01

It has been shown that animal spinal cord compression (using methods such as clips, balloons, spinal cord strapping, or calibrated forceps) mimics the persistent spinal canal occlusion that is common in human spinal cord injury (SCI). These methods can be used to investigate the effects of compression or to know the optimal timing of decompression (as duration of compression can affect the outcome of pathology) in acute SCI. Compression models involve prolonged cord compression and are distinct from contusion models, which apply only transient force to inflict an acute injury to the spinal cord. While the use of forceps to compress the spinal cord is a common choice due to it being inexpensive, it has not been critically assessed against the other methods to determine whether it is the best method to use. To date, there is no available review specifically focused on the current compression methods of inducing SCI in rats; thus, we performed a systematic and comprehensive publication search to identify studies on experimental spinalization in rat models, and this review discusses the advantages and limitations of each method.

Imaging of Spinal Cord Injury: Acute Cervical Spinal Cord Injury, Cervical Spondylotic Myelopathy, and Cord Herniation.

Science.gov (United States)

Talekar, Kiran; Poplawski, Michael; Hegde, Rahul; Cox, Mougnyan; Flanders, Adam

2016-10-01

We review the pathophysiology and imaging findings of acute traumatic spinal cord injury (SCI), cervical spondylotic myelopathy, and briefly review the much less common cord herniation as a unique cause of myelopathy. Acute traumatic SCI is devastating to the patient and the costs to society are staggering. There are currently no "cures" for SCI and the only accepted pharmacologic treatment regimen for traumatic SCI is currently being questioned. Evaluation and prognostication of SCI is a demanding area with significant deficiencies, including lack of biomarkers. Accurate classification of SCI is heavily dependent on a good clinical examination, the results of which can vary substantially based upon the patient׳s condition or comorbidities and the skills of the examiner. Moreover, the full extent of a patients׳ neurologic injury may not become apparent for days after injury; by then, therapeutic response may be limited. Although magnetic resonance imaging (MRI) is the best imaging modality for the evaluation of spinal cord parenchyma, conventional MR techniques do not appear to differentiate edema from axonal injury. Recently, it is proposed that in addition to characterizing the anatomic extent of injury, metrics derived from conventional MRI and diffusion tensor imaging, in conjunction with the neurological examination, can serve as a reliable objective biomarker for determination of the extent of neurologic injury and early identification of patients who would benefit from treatment. Cervical spondylosis is a common disorder affecting predominantly the elderly with a potential to narrow the spinal canal and thereby impinge or compress upon the neural elements leading to cervical spondylotic myelopathy and radiculopathy. It is the commonest nontraumatic cause of spinal cord disorder in adults. Imaging plays an important role in grading the severity of spondylosis and detecting cord abnormalities suggesting myelopathy. Copyright © 2016 Elsevier Inc. All rights

Spinal Cord Injury 101

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Precision of fit between implant impression coping and implant replica pairs for three implant systems.

Science.gov (United States)

Nicoll, Roxanna J; Sun, Albert; Haney, Stephan; Turkyilmaz, Ilser

2013-01-01

The fabrication of an accurately fitting implant-supported fixed prosthesis requires multiple steps, the first of which is assembling the impression coping on the implant. An imprecise fit of the impression coping on the implant will cause errors that will be magnified in subsequent steps of prosthesis fabrication. The purpose of this study was to characterize the 3-dimensional (3D) precision of fit between impression coping and implant replica pairs for 3 implant systems. The selected implant systems represent the 3 main joint types used in implant dentistry: external hexagonal, internal trilobe, and internal conical. Ten impression copings and 10 implant replicas from each of the 3 systems, B (Brånemark System), R (NobelReplace Select), and A (NobelActive) were paired. A standardized aluminum test body was luted to each impression coping, and the corresponding implant replica was embedded in a stone base. A coordinate measuring machine was used to quantify the maximum range of displacement in a vertical direction as a function of the tightening force applied to the guide pin. Maximum angular displacement in a horizontal plane was measured as a function of manual clockwise or counterclockwise rotation. Vertical and rotational positioning was analyzed by using 1-way analysis of variance (ANOVA). The Fisher protected least significant difference (PLSD) multiple comparisons test of the means was applied when the F-test in the ANOVA was significant (α=.05). The mean and standard deviation for change in the vertical positioning of impression copings was 4.3 ±2.1 μm for implant system B, 2.8 ±4.2 μm for implant system R, and 20.6 ±8.8 μm for implant system A. The mean and standard deviation for rotational positioning was 3.21 ±0.98 degrees for system B, 2.58 ±1.03 degrees for system R, and 5.30 ±0.79 degrees for system A. The P-value for vertical positioning between groups A and B and between groups A and R was <.001. No significant differences were found for

Comparison of 3D displacements of screw-retained zirconia implant crowns into implants with different internal connections with respect to screw tightening.

Science.gov (United States)

Rebeeah, Hanadi A; Yilmaz, Burak; Seidt, Jeremy D; McGlumphy, Edwin; Clelland, Nancy; Brantley, William

2018-01-01

Internal conical implant-abutment connections without horizontal platforms may lead to crown displacement during screw tightening and torque application. This displacement may affect the proximal contacts and occlusion of the definitive prosthesis. The purpose of this in vitro study was to evaluate the displacement of custom screw-retained zirconia single crowns into a recently introduced internal conical seal implant-abutment connection in 3D during hand and torque driver screw tightening. Stereolithic acrylic resin models were printed using computed tomography data from a patient missing the maxillary right central incisor. Two different internal connection implant systems (both ∼11.5 mm) were placed in the edentulous site in each model using a surgical guide. Five screw-retained single zirconia computer-aided design and computer-aided manufacturing (CAD-CAM) crowns were fabricated for each system. A pair of high-resolution digital cameras was used to record the relationship of the crown to the model. The crowns were tightened according to the manufacturers' specifications using a torque driver, and the cameras recorded their relative position again. Three-dimensional image correlation was used to measure and compare crown positions, first hand tightened and then torque driven. The displacement test was repeated 3 times for each crown. Commercial image correlation software was used to extract the data and compare the amount of displacement vertically, mesiodistally, and buccolingually. Repeated-measures ANOVA calculated the relative displacements for all 5 specimens for each implant for both crown screw hand tightening and after applied torque. A Student t test with Bonferroni correction was used for pairwise comparison of interest to determine statistical differences between the 2 implants (α=.05). The mean vertical displacements were statistically higher than the mean displacements in the mesiodistal and buccolingual directions for both implants

Technological innovations in implants used for pain therapies.

Science.gov (United States)

Shaw, Andrew; Sharma, Mayur; Deogaonkar, Milind; Rezai, Ali

2014-10-01

The field of pain management has experienced tremendous growth in implantable therapies secondary to the innovations of bioengineers, implanters, and industry. Every aspect of neuromodulation is amenable to innovation from implanting devices to anchors, electrodes, programming, and even patient programmers. Patients with previously refractory neuropathic pain syndromes have new and effective pain management strategies that are a direct result of innovations in implantable devices. Copyright © 2014 Elsevier Inc. All rights reserved.

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Tethered Spinal Cord Syndrome

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... cord over time and may be exacerbated during sports or pregnancy, or may be due to narrowing of the ... cord over time and may be exacerbated during sports or pregnancy, or may be due to narrowing of the ...

Effects of cathodal trans-spinal direct current stimulation on lower urinary tract function in normal and spinal cord injury mice with overactive bladder

Science.gov (United States)

Ahmed, Zaghloul

2017-10-01

Objective. Lower urinary tract (LUT) dysfunction is a monumental problem affecting quality of life following neurotrauma, such as spinal cord injury (SCI). Proper function of the bladder and its associated structures depends on coordinated activity of the neuronal circuitry in the spinal cord and brain. Disconnection between the spinal and brain centers controlling the LUT causes fundamental changes in the mechanisms involved in the micturition and storage reflexes. We investigated the effects of cathodal trans-spinal direct current stimulation (c-tsDCS) of the lumbosacral spine on bladder and external urinary sphincter (EUS) functions. Approach. We used cystometry and electromyography (EMG), in mice with and without SCI. Main results. c-tsDCS caused initiation of the micturition reflex in urethane-anesthetized normal mice with depressed micturition reflexes. This effect was associated with normalized EUS-EMG activity. Moreover, in urethane-anesthetized normal mice with expressed micturition reflexes, c-tsDCS increased the firing frequency, amplitude, and duration of EUS-EMG activity. These effects were associated with increased maximum intravesical pressure (P max) and intercontraction interval (ICI). In conscious normal animals, c-tsDCS caused significant increases in P max, ICI, threshold pressure (P thres), baseline pressure (P base), and number and amplitude of non-voiding contractions (NVCnumb and P im, respectively). In conscious mice with severe contusive SCI and overactive bladder, c-tsDCS increased P max, ICI, and P thres, but decreased P base, NVCnumb, and P im. c-tsDCS reduced the detrusor-overactivity/cystometry ratio, which is a measure of bladder overactivity associated with renal deterioration. Significance. These results indicate that c-tsDCS induces robust modulation of the lumbosacral spinal-cord circuitry that controls the LUT.

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Pericytes Make Spinal Cord Breathless after Injury.

Science.gov (United States)

Almeida, Viviani M; Paiva, Ana E; Sena, Isadora F G; Mintz, Akiva; Magno, Luiz Alexandre V; Birbrair, Alexander

2017-09-01

Traumatic spinal cord injury is a devastating condition that leads to significant neurological deficits and reduced quality of life. Therapeutic interventions after spinal cord lesions are designed to address multiple aspects of the secondary damage. However, the lack of detailed knowledge about the cellular and molecular changes that occur after spinal cord injury restricts the design of effective treatments. Li and colleagues using a rat model of spinal cord injury and in vivo microscopy reveal that pericytes play a key role in the regulation of capillary tone and blood flow in the spinal cord below the site of the lesion. Strikingly, inhibition of specific proteins expressed by pericytes after spinal cord injury diminished hypoxia and improved motor function and locomotion of the injured rats. This work highlights a novel central cellular population that might be pharmacologically targeted in patients with spinal cord trauma. The emerging knowledge from this research may provide new approaches for the treatment of spinal cord injury.

Impact of an implanted neuroprosthesis on community ambulation in incomplete SCI.

Science.gov (United States)

Lombardo, Lisa M; Kobetic, Rudolf; Pinault, Gilles; Foglyano, Kevin M; Bailey, Stephanie N; Selkirk, Stephen; Triolo, Ronald J

2018-03-01

Test the effect of a multi-joint control with implanted electrical stimulation on walking after spinal cord injury (SCI). Single subject research design with repeated measures. Hospital-based biomechanics laboratory and user assessment of community use. Female with C6 AIS C SCI 30 years post injury. Lower extremity muscle activation with an implanted pulse generator and gait training. Walking speed, maximum distance, oxygen consumption, upper extremity (UE) forces, kinematics and self-assessment of technology. Short distance walking speed at one-year follow up with or without stimulation was not significantly different from baseline. However, average walking speed was significantly faster (0.22 m/s) with stimulation over longer distances than volitional walking (0.12 m/s). In addition, there was a 413% increase in walking distance from 95 m volitionally to 488 m with stimulation while oxygen consumption and maximum upper extremity forces decreased by 22 and 16%, respectively. Stimulation also produced significant (P ≤ 0.001) improvements in peak hip and knee flexion, ankle angle at foot off and at mid-swing. An implanted neuroprosthesis enabled a subject with incomplete SCI to walk longer distances with improved hip and knee flexion and ankle dorsiflexion resulting in decreased oxygen consumption and UE support. Further research is required to determine the robustness, generalizability and functional implications of implanted neuroprostheses for community ambulation after incomplete SCI.

Cord Blood Banking for Potential Future Transplantation.

Science.gov (United States)

Shearer, William T; Lubin, Bertram H; Cairo, Mitchell S; Notarangelo, Luigi D

2017-11-01

This policy statement is intended to provide information to guide pediatricians, obstetricians, and other medical specialists and health care providers in responding to parents' questions about cord blood donation and banking as well as the types (public versus private) and quality of cord blood banks. Cord blood is an excellent source of stem cells for hematopoietic stem cell transplantation in children with some fatal diseases. Cord blood transplantation offers another method of definitive therapy for infants, children, and adults with certain hematologic malignancies, hemoglobinopathies, severe forms of T-lymphocyte and other immunodeficiencies, and metabolic diseases. The development of universal screening for severe immunodeficiency assay in a growing number of states is likely to increase the number of cord blood transplants. Both public and private cord blood banks worldwide hold hundreds of thousands of cord blood units designated for the treatment of fatal or debilitating illnesses. The procurement, characterization, and cryopreservation of cord blood is free for families who choose public banking. However, the family cost for private banking is significant and not covered by insurance, and the unit may never be used. Quality-assessment reviews by several national and international accrediting bodies show private cord blood banks to be underused for treatment, less regulated for quality control, and more expensive for the family than public cord blood banks. There is an unquestionable need to study the use of cord blood banking to make new and important alternative means of reconstituting the hematopoietic blood system in patients with malignancies and blood disorders and possibly regenerating tissue systems in the future. Recommendations regarding appropriate ethical and operational standards (including informed consent policies, financial disclosures, and conflict-of-interest policies) are provided for physicians, institutions, and organizations that

Spinal Cord Injury 101

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Factors affecting directional migration of bone marrow mesenchymal stem cells to the injured spinal cord

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Xia, Peng; Pan, Su; Cheng, Jieping; Yang, Maoguang; Qi, Zhiping; Hou, Tingting; Yang, Xiaoyu

2014-01-01

Microtubule-associated protein 1B plays an important role in axon guidance and neuronal migration. In the present study, we sought to discover the mechanisms underlying microtubule-associated protein 1B mediation of axon guidance and neuronal migration. We exposed bone marrow mesenchymal stem cells to okadaic acid or N-acetyl-D-erythro-sphingosine (an inhibitor and stimulator, respectively, of protein phosphatase 2A) for 24 hours. The expression of the phosphorylated form of type I microtubule-associated protein 1B in the cells was greater after exposure to okadaic acid and lower after N-acetyl-D-erythro-sphingosine. We then injected the bone marrow mesenchymal stem cells through the ear vein into rabbit models of spinal cord contusion. The migration of bone marrow mesenchymal stem cells towards the injured spinal cord was poorer in cells exposed to okadaic acid- and N-acetyl-D-erythro-sphingosine than in non-treated bone marrow mesenchymal stem cells. Finally, we blocked phosphatidylinositol 3-kinase (PI3K) and extracellular signal-regulated kinase 1/2 (ERK1/2) pathways in rabbit bone marrow mesenchymal stem cells using the inhibitors LY294002 and U0126, respectively. LY294002 resulted in an elevated expression of phosphorylated type I microtubule-associated protein 1B, whereas U0126 caused a reduction in expression. The present data indicate that PI3K and ERK1/2 in bone marrow mesenchymal stem cells modulate the phosphorylation of microtubule-associated protein 1B via a cross-signaling network, and affect the migratory efficiency of bone marrow mesenchymal stem cells towards injured spinal cord. PMID:25374590

Influences of microgap and micromotion of implant-abutment interface on marginal bone loss around implant neck.

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Liu, Yang; Wang, Jiawei

2017-11-01

To review the influences and clinical implications of micro-gap and micro-motion of implant-abutment interface on marginal bone loss around the neck of implant. Literatures were searched based on the following Keywords: implant-abutment interface/implant-abutment connection/implant-abutment conjunction, microgap, micromotion/micromovement, microleakage, and current control methods available. The papers were then screened through titles, abstracts, and full texts. A total of 83 studies were included in the literature review. Two-piece implant systems are widely used in clinics. However, the production error and masticatory load result in the presence of microgap and micromotion between the implant and the abutment, which directly or indirectly causes microleakage and mechanical damage. Consequently, the degrees of microgap and micromotion further increase, and marginal bone absorption finally occurs. We summarize the influences of microgap and micromotion at the implant-abutment interface on marginal bone loss around the neck of the implant. We also recommend some feasible methods to reduce their effect. Clinicians and patients should pay more attention to the mechanisms as well as the control methods of microgap and micromotion. To reduce the corresponding detriment to the implant marginal bone, suitable Morse taper or hybrid connection implants and platform switching abutments should be selected, as well as other potential methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

CT-myelography of cervical cord injury

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Koyanagi, Izumi; Isu, Toyohiko; Iwasaki, Yoshinobu

1986-01-01

We reported seven cases of acute cervical cord injuries who were examined by CT-Myelography (CTM) within 7 days after trauma. The presence or absence of spinal cord enlargement, the initial neurological status and the neurological prognosis of these patients were studied. The neurological status of each patient was graded by the method of Frankel who defined five grades from A to E according to the severity of neurological deficits. Seven patients were all males. The youngest was 18 and the oldest was 73 years old, with a mean age of 40.7 years. Follows up periods ranged from 7 to 23 months. Result: CTM revealed the enlargement of spinal cord in two cases, who had severe neurological deficits and were graded to A. No neurological improvements were obtained in these cases. Five cases without cord enlargement were graded to A in one patient, B in one patient and C in three patients. Four of these five patients improved neurologically. One grade C patient remained grade C. Complete block of subarachnoid space was observed in two out of seven cases. Cord enlargement was present in one of them. Another case of complete block improved from C to D. Conclusion: We consider the presence of cord enlargement which can be demonstrated by CTM well correlates the severity of the cord damage and presume poor neurological prognosis. Internal decompression, such as posterior longitudinal myelotomy may be recommended to the case of cord enlargement. When the cord enlargement is absent, improvement of neurological grade is expected although the initial neurological status shows severe deficits. (author)

Photoplethysmographic sensors for perfusion measurements in spinal cord tissue

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Phillips, J P; Kyriacou, P A, E-mail: Justin.Phillips.1@city.ac.uk [School of Engineering and Mathematical Sciences, City University London, EC1V 0HB (United Kingdom)

2011-08-17

Sensors for recording photoplethysmographic signals from the nervous tissue of the spinal cord are described. The purpose of these sensors is to establish whether perfusion is compromised in various states of injury which occur in certain animal models of spinal cord injury, for example compression injury. Various measures of perfusion are applicable such as the amplitude of the photoplethysmograph signal and the oxygen saturation, measured using a dual wavelength configuration. Signals are usually compared to baseline measurements made in uninjured subjects. This paper describes two types of probe, one based on optical fibres, and one in which optotes are placed in direct contact with the tissue surface. Results from a study based on a compression model utilising a fibreoptic sensor are presented.

Patterns of Biomarkers in Cord Blood During Pregnancy and Preeclampsia.

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Kharb, S; Nanda, S

2017-01-01

Umbilical cord blood (UCB) is in contact with all the fetal tissues and can reflect the state of fetus and UCB can be compared with maternal blood. Inflammatory, metabolic and immunological disorders during pregnancy can affect the environment in which the fetus is developing and may produce various alterations. To analyze different biochemical parameters in maternal venous blood and new born umbilical cord blood from healthy normotensive pregnant and preeclamptic women. Homocysteine, folate, B12, heme oxygenase-1 (HO-1), endoglin, leptin, cholinesterase, IGF-1, Apo A, lipoproteins, TSH, fT3, fT4 were analyzed in maternal sera and venous umbilical cord sera of newborns of twenty five preeclamptics (group II) and twenty five normotensive pregnant women (group I). Homocysteine, folic acid, vitamin B12, Apo A I & II, TSH, fT3, fT4 levels were estimated by competitive immunoassay using direct chemiluminiscence technology. Heme oxygenase-1 (HO-1), endoglin, leptin, cholinesterase, IGF-1 were analyzed by ELISA. Maternal and cord blood levels of homocysteine, folic acid, lipid profile (namely, total cholesterol, triglycerides, LDL-C, VLDL-C and HDL-C), TSH, heme oxygenase 1, were higher in preeclamptic women as compared to normotensive pregnant women. Endoglin levels were significantly lower in cord blood of preeclamptic mother as compared to normotensive mothers. Serum and cord blood vitamin B12, Apo A-I and Apo B l, cholinesterase, leptin levels, IGF-I were lower in preeclamptic women as compared to normotensive pregnant. Findings of the present study suggest that biochemical alterations occur in mothers and fetuses and modifications of uterine environment (in terms of thyroxine and folate and vitamin B12 supplementation) can be of help. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Radiotherapy Suppresses Bone Cancer Pain through Inhibiting Activation of cAMP Signaling in Rat Dorsal Root Ganglion and Spinal Cord

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Guiqin Zhu

2016-01-01

Full Text Available Radiotherapy is one of the major clinical approaches for treatment of bone cancer pain. Activation of cAMP-PKA signaling pathway plays important roles in bone cancer pain. Here, we examined the effects of radiotherapy on bone cancer pain and accompanying abnormal activation of cAMP-PKA signaling. Female Sprague-Dawley rats were used and received tumor cell implantation (TCI in rat tibia (TCI cancer pain model. Some of the rats that previously received TCI treatment were treated with X-ray radiation (radiotherapy. Thermal hyperalgesia and mechanical allodynia were measured and used for evaluating level of pain caused by TCI treatment. PKA mRNA expression in dorsal root ganglion (DRG was detected by RT-PCR. Concentrations of cAMP, IL-1β, and TNF-α as well as PKA activity in DRG and the spinal cord were measured by ELISA. The results showed that radiotherapy significantly suppressed TCI-induced thermal hyperalgesia and mechanical allodynia. The level of PKA mRNA in DRG, cAMP concentration and PKA activity in DRG and in the spinal cord, and concentrations of IL-1β and TNF-α in the spinal cord were significantly reduced by radiotherapy. In addition, radiotherapy also reduced TCI-induced bone loss. These findings suggest that radiotherapy may suppress bone cancer pain through inhibition of activation of cAMP-PKA signaling pathway in DRG and the spinal cord.

Clinical Trial of Human Fetal Brain-Derived Neural Stem/Progenitor Cell Transplantation in Patients with Traumatic Cervical Spinal Cord Injury

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Ji Cheol Shin

2015-01-01

Full Text Available In a phase I/IIa open-label and nonrandomized controlled clinical trial, we sought to assess the safety and neurological effects of human neural stem/progenitor cells (hNSPCs transplanted into the injured cord after traumatic cervical spinal cord injury (SCI. Of 19 treated subjects, 17 were sensorimotor complete and 2 were motor complete and sensory incomplete. hNSPCs derived from the fetal telencephalon were grown as neurospheres and transplanted into the cord. In the control group, who did not receive cell implantation but were otherwise closely matched with the transplantation group, 15 patients with traumatic cervical SCI were included. At 1 year after cell transplantation, there was no evidence of cord damage, syrinx or tumor formation, neurological deterioration, and exacerbating neuropathic pain or spasticity. The American Spinal Injury Association Impairment Scale (AIS grade improved in 5 of 19 transplanted patients, 2 (A → C, 1 (A → B, and 2 (B → D, whereas only one patient in the control group showed improvement (A → B. Improvements included increased motor scores, recovery of motor levels, and responses to electrophysiological studies in the transplantation group. Therefore, the transplantation of hNSPCs into cervical SCI is safe and well-tolerated and is of modest neurological benefit up to 1 year after transplants. This trial is registered with Clinical Research Information Service (CRIS, Registration Number: KCT0000879.

Role of clinician's experience and implant design on implant stability. An ex vivo study in artificial soft bones.

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Romanos, Georgios E; Basha-Hijazi, Abdulaziz; Gupta, Bhumija; Ren, Yan-Fang; Malmstrom, Hans

2014-04-01

Clinical experience in implant placement is important in order to prevent implant failures. However, the implant design affects the primary implant stability (PS) especially in poor quality bones. Therefore, the aim of this study was to compare the effect of clinician surgical experience on PS, when placing different type of implant designs. A total of 180 implants (90 parallel walled-P and 90 tapered-T) were placed in freshly slaughtered cow ribs. Bone quality was evaluated by two examiners during surgery and considered as 'type IV' bone. Implants (ø 5 mm, length: 15 mm, Osseotite, BIOMET 3i, Palm Beach Gardens, FL, USA) were placed by three different clinicians (master/I, good/II, non-experienced/III, under direct supervision of a manufacturer representative; 30 implants/group). An independent observer assessed the accuracy of placement by resonance frequency analysis (RFA) with implant stability quotient (ISQ) values. Two-way analysis of variance (ANOVA) and Tukey's post hoc test were used to detect the surgical experience of the clinicians and their interaction and effects of implant design on the PS. All implants were mechanically stable. The mean ISQ values were: 49.57(± 18.49) for the P-implants and 67.07(± 8.79) for the T-implants. The two-way ANOVA showed significant effects of implant design (p bone. © 2012 Wiley Periodicals, Inc.

Diagnosis and surgical treatment of terminal syringomyelia within spinal cord combined with tethered cord syndrome

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Jing-cheng XIE

2016-04-01

Full Text Available Objective To summarize the clinical manifestations, imaging characteristics and experience of surgical treatment of spinal cord terminal syringomyelia with tethered cord syndrome (TCS.  Methods and Results Clinical data of 10 patients with spinal cord syringomyelia combined with TCS surgically treated under microscope from January 1999 to March 2014 in our hospital were retrospectively analyzed. There were 3 males and 7 females with average age of 15.06 years old (ranged from 2 to 35 years old. The course of disease ranged from 3 months to 20 years (average 42.17 months. Among those patients, one patient presented hydromyelia, 8 patients suffered from meningeal cyst within the sacral canal, and one patient were concurrent with sacral dermal sinus. The weakness of lower extremities, especially distal limbs, was the main clinical manifestation. Five patients were accompanied with bowel and bladder dysfunction and 5 patients with sensory disturbance below the level of syringomyelia, especially hypesthesia. Preoperative MRI showed conus medullaris disappeared at the end of spinal cord, and there was fluid signal in the lower spinal cord with hypo-intensity signal in T1WI and hyper-intensity signal in T2WI without enhancement. All patients underwent surgical procedures. Under microscope, filum terminale was cut off, drainage was performed, meningeal cyst within the sacral canal was removed, and tethered cord was released. The success rate of operations was 100%. The duration of surgery ranged from 1.52 to 3.07 h (average 2.15 h, with average intraoperative blood loss 220 ml (ranged from 100 to 410 ml. The tethering filum had been totally resected and histological examination showed typical filum tissue in all cases. No operative complication was found. Visual Analogue Scale (VAS score was decreased, and the lower limbs weakness as well as bowel and bladder dysfunction was gradually relieved after operation. The period of follow-up was ranged from 6

The Protective Effect of Spinal Cord Stimulation Postconditioning Against Spinal Cord Ischemia/Reperfusion Injury in Rabbits.

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Li, Huixian; Dong, Xiuhua; Jin, Mu; Cheng, Weiping

2018-01-18

Delayed paraplegia due to spinal cord ischemia/reperfusion injury (IRI) remains one of the most severe complications of thoracoabdominal aneurysm surgery, for which effective prevention and treatment is still lacking. The current study investigates whether spinal cord stimulation (SCS) postconditioning has neuroprotective effects against spinal cord IRI. Ninety-six New Zealand white male rabbits were randomly divided into four groups as follows: a sham group and three experimental groups (C group, 2 Hz group, and 50 Hz group) n = 24/group. Spinal cord ischemia was induced by transient infrarenal aortic balloon occlusion for 28 min, after which rabbits in group C underwent no additional intervention, while rabbits in the other two experimental groups underwent 2 Hz or 50 Hz epidural SCS for 30 min at the onset of reperfusion and then daily until sacrifice. Hind limb neurologic function of rabbits was assessed using Jacob scale. Lumbar spinal cords were harvested immediately after sacrifice for histological examination and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. The number of viable α-motor neurons in ventral horn was counted and TUNEL-positive rate of α-motor neurons was calculated. Spinal cord IRI was caused by transient infrarenal aorta occlusion for 28 min. Both 2 Hz and 50 Hz SCS postconditioning had neuroprotective effects, particularly the 2 Hz SCS postconditioning. Comparing to C group and 50 Hz group, rabbits in the 2 Hz group demonstrated better hind limb motor function and a lower rate of TUNEL-positive α-motor neuron after eight hours, one day, three days, and seven days of spinal cord reperfusion. More viable α-motor neurons were preserved after one and three days of spinal cord reperfusion in 2 Hz group rabbits than in C group and 50 Hz group rabbits. SCS postconditioning at 2 Hz protected the spinal cord from IRI. © 2018 International Neuromodulation Society.

Reliable and fast volumetry of the lumbar spinal cord using cord image analyser (Cordial).

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Tsagkas, Charidimos; Altermatt, Anna; Bonati, Ulrike; Pezold, Simon; Reinhard, Julia; Amann, Michael; Cattin, Philippe; Wuerfel, Jens; Fischer, Dirk; Parmar, Katrin; Fischmann, Arne

2018-04-30

To validate the precision and accuracy of the semi-automated cord image analyser (Cordial) for lumbar spinal cord (SC) volumetry in 3D T1w MRI data of healthy controls (HC). 40 3D T1w images of 10 HC (w/m: 6/4; age range: 18-41 years) were acquired at one 3T-scanner in two MRI sessions (time interval 14.9±6.1 days). Each subject was scanned twice per session, allowing determination of test-retest reliability both in back-to-back (intra-session) and scan-rescan images (inter-session). Cordial was applied for lumbar cord segmentation twice per image by two raters, allowing for assessment of intra- and inter-rater reliability, and compared to a manual gold standard. While manually segmented volumes were larger (mean: 2028±245 mm 3 vs. Cordial: 1636±300 mm 3 , p<0.001), accuracy assessments between manually and semi-automatically segmented images showed a mean Dice-coefficient of 0.88±0.05. Calculation of within-subject coefficients of variation (COV) demonstrated high intra-session (1.22-1.86%), inter-session (1.26-1.84%), as well as intra-rater (1.73-1.83%) reproducibility. No significant difference was shown between intra- and inter-session reproducibility or between intra-rater reliabilities. Although inter-rater reproducibility (COV: 2.87%) was slightly lower compared to all other reproducibility measures, between rater consistency was very strong (intraclass correlation coefficient: 0.974). While under-estimating the lumbar SCV, Cordial still provides excellent inter- and intra-session reproducibility showing high potential for application in longitudinal trials. • Lumbar spinal cord segmentation using the semi-automated cord image analyser (Cordial) is feasible. • Lumbar spinal cord is 40-mm cord segment 60 mm above conus medullaris. • Cordial provides excellent inter- and intra-session reproducibility in lumbar spinal cord region. • Cordial shows high potential for application in longitudinal trials.

Direct and indirect pathways to lamina I in the medulla oblongata and spinal cord of the cat

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Holstege, Gert

1988-01-01

The pathways to lamina I in the medulla oblongata and spinal cord of the cat were traced using horse-radish-peroxidase (HRP) and autoradiographic techniques. The HRP results indicated that several neuronal cell groups in the brain stem and hypothalamus project to the spinal cord throughout its total length. The autoradiographic tracing results demonstrated that the strongest projections to lamina I are derived from the following four areas: the caudal nucleus raphe magnus (NRM), the ventral part of the caudal pontine and NRM, the contralaterally projecting lateral pontine or paralemniscal tegmentum, and the paraventricular nucleus of the hypothalamus. In addition, a limited, especially at lumbosacral levels, distinct projection to lamina I was found to originate in the most caudal part of the medullary tegmentum.

Umbilical Cord Blood: Counselling, Collection, and Banking.

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Armson, B Anthony; Allan, David S; Casper, Robert F

2015-09-01

To review current evidence regarding umbilical cord blood counselling, collection, and banking and to provide guidelines for Canadian health care professionals regarding patient education, informed consent, procedural aspects, and options for cord blood banking in Canada. Selective or routine collection and banking of umbilical cord blood for future stem cell transplantation for autologous (self) or allogeneic (related or unrelated) treatment of malignant and non-malignant disorders in children and adults. Cord blood can be collected using in utero or ex utero techniques. Umbilical cord blood counselling, collection, and banking, education of health care professionals, indications for cord blood collection, short- and long-term risk and benefits, maternal and perinatal morbidity, parental satisfaction, and health care costs. Published literature was retrieved through searches of Medline and PubMed beginning in September 2013 using appropriate controlled MeSH vocabulary (fetal blood, pregnancy, transplantation, ethics) and key words (umbilical cord blood, banking, collection, pregnancy, transplantation, ethics, public, private). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date limits, but results were limited to English or French language materials. Searches were updated on a regular basis and incorporated in the guideline to September 2014. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, and national and international medical specialty societies. The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). Umbilical cord blood is a readily available source of hematopoetic stem cells used with increasing frequency as an alternative to

SU-F-T-03: Radiobiological Evaluation of a Directional Brachytherapy Device Surgically Implanted Following EBRT

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Rivard, MJ [Tufts University School of Medicine, Boston, MA (United States); Emrich, JG; Poli, J [Drexel University College of Medicine, Philadelphia, PA (United States)

2016-06-15

Purpose: Preceding surgical implantation following external-beam radiotherapy (EBRT) delivery, a radiobiological evaluation was performed for a new LDR Pd-103 directional brachytherapy device (CivaSheet). As this was the first case with the device used in combination with EBRT, there was concern to determine the appropriate prescription dose. Methods: The radiobiological model of Dale (1985, 1989) was used for a permanent LDR implant including radioactive decay. The biological effective dose (BED) was converted to the equivalent dose in 2 Gy fractions (EQD2) for comparison with EBRT prescription expectations. Given IMRT delivery of 50.4 Gy, an LDR brachytherapy dose of approximately 15–20 Gy EQD2 was desired. To be specific to the treatment site (leiomyosarcoma T2bN0M0, grade 2 with R1 surgical margin), the radiobiological model required several radiobiological parameters with values taken from the literature. A sensitivity analysis was performed to determine their relative importance on the calculated BED and subsequent EQD2. The Pd-103 decay constant (λ=0.0017 h{sup −1}) was also used. DVHs were prepared for pre- and post-surgical geometries to glean the possible and realized implant geometric configuration. DVHs prepared in VariSeed9 were converted to BEDVHs and subsequently EQD2 values for each volume-element. Results: For a physical dose of 28 Gy to a 0.5 cm depth, BED=21.7 Gy and EQD2=17.6 Gy, which was near the center of the desired EQD2 range. Tumor bed (CTV=4 cm{sup 3}) coverage was 99.2% with 48 sources implanted. In order of decreasing importance from the sensitivity analysis, the radiobiological parameters were α=0.25 Gy{sup −1}, T{sub POT}=23 days, α/β=8.6 Gy, and T=1.5 h. Percentage variations in these values produced EQD2 variations of 40%, 20%, 18%, and 1%, respectively. Conclusion: This radiobiological evaluation indicated that prescription dose may be determined for comparison with the desired EQD2, and that radiobiologicalparameter

Distribution of elements in human spinal cord

International Nuclear Information System (INIS)

Yukawa, Masae; Kobayashi, T.; Qiu, Y.; Kameda, N.; Ito, Y.; Otomo, E.

1992-01-01

The distribution of elements in human spinal cord was investigated on unfixed frozen cord material using PIXE technique. Distribution of Cu, Zn and Fe were not uniform in the cross section of the spinal cord and concentrations of these elements were higher in the anterior gray horn than in the other areas, while K and Cl distributed uniformly. The content of K changed along the spinal cord from the cervical to the lumbar level. These findings are discussed in relation to current understanding of the physiology of the spinal cord. (author)

Radiation treatment of spinal cord neoplasms

International Nuclear Information System (INIS)

Smirnov, R.V.

1982-01-01

Results of radiation treatment of spinal cord neoplasms are presented. The results of combined (surgical and radiation) treatment of tumors are studied. On the whole it is noted that radiation treatment of initial spinal cord tumours is not practised on a large scale because of low radiostability of spinal cord

Spinal cord involvement in tuberculous meningitis.

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Garg, R K; Malhotra, H S; Gupta, R

2015-09-01

To summarize the incidence and spectrum of spinal cord-related complications in patients of tuberculous meningitis. Reports from multiple countries were included. An extensive review of the literature, published in English, was carried out using Scopus, PubMed and Google Scholar databases. Tuberculous meningitis frequently affects the spinal cord and nerve roots. Initial evidence of spinal cord involvement came from post-mortem examination. Subsequent advancement in neuroimaging like conventional lumbar myelography, computed tomographic myelography and gadolinium-enhanced magnetic resonance-myelography have contributed immensely. Spinal involvement manifests in several forms, like tuberculous radiculomyelitis, spinal tuberculoma, myelitis, syringomyelia, vertebral tuberculosis and very rarely spinal tuberculous abscess. Frequently, tuberculous spinal arachnoiditis develops paradoxically. Infrequently, spinal cord involvement may even be asymptomatic. Spinal cord and spinal nerve involvement is demonstrated by diffuse enhancement of cord parenchyma, nerve roots and meninges on contrast-enhanced magnetic resonance imaging. High cerebrospinal fluid protein content is often a risk factor for arachnoiditis. The most important differential diagnosis of tuberculous arachnoiditis is meningeal carcinomatosis. Anti-tuberculosis therapy is the main stay of treatment for tuberculous meningitis. Higher doses of corticosteroids have been found effective. Surgery should be considered only when pathological confirmation is needed or there is significant spinal cord compression. The outcome in these patients has been unpredictable. Some reports observed excellent recovery and some reported unfavorable outcomes after surgical decompression and debridement. Tuberculous meningitis is frequently associated with disabling spinal cord and radicular complications. Available treatment options are far from satisfactory.

Channeling effect for low energy ion implantation in Si

International Nuclear Information System (INIS)

Cho, K.; Allen, W.R.; Finstad, T.G.; Chu, W.K.; Liu, J.; Wortman, J.J.

1985-01-01

Ion implantation is one of the most important processes in semiconductor device fabrication. Due to the crystalline nature of Si, channeling of implanted ions occurs during this process. Modern devices become smaller and shallower and therefore require ion implantation at lower energies. The effect of channeling on ion implantation becomes a significant problem for low energy ion implantation. The critical angle for axial and planar channeling increases with decreasing energy. This corresponds to an increased probability for channeling with lowering of ion energy. The industry approach to avoid the channeling problem is to employ a tilt angle of 7 0 between the ion implantation direction and the surface normal. We approach the problem by mapping major crystalline axes and planes near the [100] surface normal. Our analysis indicates that a 7 0 tilt is not an optimum selection in channeling reduction. Tilt angles in the range 5 0 to 6 0 combined with 7 0 +- 0.5 0 rotation from the (100) plane are better selections for the reduction of the channeling effect. The range of suitable angles is a function of the implantation energy. Implantations of boron along well specified crystallographic directions have been carried out by careful alignment and the resulting boron profiles measured by SIMS. (orig.)

Lower thoracic spinal cord stimulation to restore cough in patients with spinal cord injury: results of a National Institutes of Health-Sponsored clinical trial. Part II: clinical outcomes.

Science.gov (United States)

DiMarco, Anthony F; Kowalski, Krzysztof E; Geertman, Robert T; Hromyak, Dana R; Frost, Fredrick S; Creasey, Graham H; Nemunaitis, Gregory A

2009-05-01

To evaluate the clinical effects of spinal cord stimulation (SCS) to restore cough in subjects with cervical spinal cord injury. Clinical trial assessing the clinical outcomes and side effects associated with the cough system. Outpatient hospital or residence. Subjects (N=9; 8 men, 1 woman) with cervical spinal cord injury. SCS was performed at home by either the subjects themselves or caregivers on a chronic basis and as needed for secretion management. Ease in raising secretions, requirement for trained caregiver support related to secretion management, and incidence of acute respiratory tract infections. The degree of difficulty in raising secretions improved markedly, and the need for alternative methods of secretion removal was virtually eliminated. Subject life quality related to respiratory care improved, with subjects reporting greater control of breathing problems and enhanced mobility. The incidence of acute respiratory tract infections fell from 2.0+/-0.5 to 0.7+/-0.4 events/subject year (P<.01), and mean level of trained caregiver support related to secretion management measured over a 2-week period decreased from 16.9+/-7.9 to 2.1+/-1.6 and 0.4+/-0.3 times/wk (P<.01) at 28 and 40 weeks after implantation of the device, respectively. Three subjects developed mild hemodynamic effects that abated completely with continued SCS. Subjects experienced mild leg jerks during SCS, which were well tolerated. There were no instances of bowel or bladder leakage. Restoration of cough via SCS is safe and efficacious. This method improves life quality and has the potential to reduce the morbidity and mortality associated with recurrent respiratory tract infections in this patient population.

Evaluation and Comparison of Accuracy of Measuring the Position of Miniscrew Implants using Two-dimensional Orthopantomogram and a Three-dimensional Imaging with Direct Method on Dried Skull

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R H Kamble

2011-01-01

Conclusion: Ortopantomogram shows more variations on linear and angular measurements as compared to direct method and 3D radiography whereas direct method and 3D radiography show no difference. But, we can calculate the angulations of miniscrew implant placement by angular regression model.

Therapeutic approaches for spinal cord injury

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Alexandre Fogaça Cristante

2012-10-01

Full Text Available This study reviews the literature concerning possible therapeutic approaches for spinal cord injury. Spinal cord injury is a disabling and irreversible condition that has high economic and social costs. There are both primary and secondary mechanisms of damage to the spinal cord. The primary lesion is the mechanical injury itself. The secondary lesion results from one or more biochemical and cellular processes that are triggered by the primary lesion. The frustration of health professionals in treating a severe spinal cord injury was described in 1700 BC in an Egyptian surgical papyrus that was translated by Edwin Smith; the papyrus reported spinal fractures as a ''disease that should not be treated.'' Over the last biological or pharmacological treatment method. Science is unraveling the mechanisms of cell protection and neuroregeneration, but clinically, we only provide supportive care for patients with spinal cord injuries. By combining these treatments, researchers attempt to enhance the functional recovery of patients with spinal cord injuries. Advances in the last decade have allowed us to encourage the development of experimental studies in the field of spinal cord regeneration. The combination of several therapeutic strategies should, at minimum, allow for partial functional recoveries for these patients, which could improve their quality of life.

Direct emergence of the dorsospinal artery from the aorta and spinal cord blood supply. Case reports and literature review

International Nuclear Information System (INIS)

Siclari, Francesca; Fasel, Jean H.D.; Gailloud, Philippe

2006-01-01

Direct emergence of a dorsospinal artery from the aorta is a rare anatomic variant, of which a total of seven cases have been reported. This report offers an additional angiographic observation and reviews the literature. Two observations of common intercostal trunks documented during spinal angiography are described. In the first observation, the common intercostal trunk provided complete blood supply to two adjacent vertebral levels (T11 and T12). In other words, the trunk included an intercostal branch and a dorsospinal branch for each level. In the second observation, the common intercostal trunk provided an intercostal branch for each level (T9 and T10), but only one dorsospinal branch (T10). An isolated dorsospinal artery (DA) originated separately from the aorta at the T9 level, and provided a significant contribution to the anterior spinal axis. The two reported cases illustrate the concept of ''complete'' versus ''incomplete'' common intercostal trunks. In instances where an incomplete trunk is documented, a separate DA originating directly from the aorta must be looked for. A review of the literature indicates a tendency for isolated DAs to participate in the blood supply to the spinal cord. (orig.)

[RECONSTRUCTION OF LOWER EXTREMITY FUNCTION OF COMPLETE SPINAL CORD INJURY RATS BY FIRST NEURON CONNECTION].

Science.gov (United States)

Wang, Fangyong; Yuan, Yuan; Li, Jianjun

2015-12-01

To investigate the effects of the first neuron connection for the reconstruction of lower extremity function of complete spinal cord injury rats. Forty adult female Sprague Dawley rats of 300-350 g in weight were selected to prepare the models of L₁ transverse spinal cord injury. After 2 weeks of establishing model, the rats were randomly divided into control group (n = 20) and experimental group (n = 20). In the experimental group, the right hind limb function was reconstructed directly by the first neuron; in the control group, the other treatments were the same to the experimental group except that the distal tibial nerve and the proximal femoral nerve were not sutured. The recovery of motor function of lower extremity was observed by the Basso-Beattie-Bresnahan (BBB) scoring system on bilateral hind limbs at 7, 30, 50, and 70 days after operation. The changes of the spinal cord were observed by HE staining, neurofilament 200 immunohistochemistry staining, and the technique of horseradish peroxidase (HRP) tracing. After establishing models, 6 rats died. The right hind limb had no obvious recovery of the motor function, with the BBB score of 0 in 2 groups; the left hind limb motor function was recovered in different degrees, and there was no significant difference in BBB score between 2 groups (P > 0.05). In the experimental group, HE staining showed that the spinal cord was reconstructed with the sciatic nerve, which was embedded in the spinal cord, and the sciatic nerve membrane was clearly identified, and there was no obvious atrophy in the connecting part of the spinal cord. In the experimental group, the expression of nerve fiber was stained with immunohistochemistry, and the axons of the spinal cord were positively by stained and the peripheral nerve was connected with the spinal cord. HRP labelled synapses were detected by HRP retrograde tracing in the experimental group, while there was no HRP labelled synapse in the control group. Direct reconstruction

Umbilical cord blood for unrelated bone marrow replacement; Asia bank and Japan cord blood bank network update.

Science.gov (United States)

Mugishima, Hideo; Takahashi, Tuneo; Nagamura, Tokiko; Asano, Sigetaka; Saito, Hidehiko

2002-08-01

Cord blood offers many advantages including a high concentration of hematopoietic stem cells, a large number of potential donors, and ease of harvest. Furthermore, since there is no risk for either the mother or baby, few people refuse to donate. There is thought to be a low risk for virus contamination and also probably a low incidence and severity of GVHD. Cord blood can be obtained quickly without the assistance of a coordinator and one or 2 locus-mismatched HLA is usually acceptable. In Japan, there are 10 cord blood banks supported by the government. Between 1996 and June 2002, 9,500 units were registered with the Japan cord blood bank network (JCBBN). 630 units were delivered and most of these were transplanted. The status of registered cord blood units worldwide is shown. 59,081 units have been registered by NETCORD. The Japan cord blood bank network accounts for 13% of these units. I will discuss the Tokyo cord blood tank (TCBB). The bank at Tokyo, to which we belong, is one of the largest banks in Japan. We helped to establish Asia CORD in 2000 and have held annual conferences and meetings in Tokyo to exchange information. So far, China, Korea, Taiwan, Thailand, Viet Nam and Japan have participated. We accepted three trainees from the Ho Chi Minh City Blood Transfusion and Hematology Center for training in cord blood transplantation in May 2001. In January 2002, a patient with ALL received cord blood and was successfully engrafted at Ho Chi Minh City Blood Transfusion and Hematology Center. We present here the clinical outcome of these patients through Tokyo cord blood bank and Japan cord blood bank network. First, the number of CB units stored and registered at JCBBN and TCBB has increased rapidly over the past two years. Second, the survival rate of acute leukemia patients in release was significantly lower than that in patients in CR. Third, the engraftment rate in patients with metabolic disease (50%) was lower than that in patients with leukemia

Barriers and motivators to blood and cord blood donations in young African-American women.

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Grossman, Brenda; Watkins, Andre R; Fleming, Faye; Debaun, Michael R

2005-03-01

The primary aim of this study was to assess potential barriers and motivators to blood and cord blood donation among African-American women. A telephone survey of African-American women, ages 18-30 years, in the St. Louis metropolitan area was performed. The survey was administered by trained telemarketing personnel using a Computer-Assisted Direct Interview (CADI) system. One hundred sixty-two women were surveyed. Common barriers to blood donation were inconvenience of donor sites (19%), fear of needles (16%), and too much time required to donate (15%). Potential motivators were increasing awareness of need for blood (43%), increasing the number of convenient donor locations (19%), and encouragement by spiritual leaders to have blood drives at their church (17%). Lack of awareness was the only identified barrier to cord blood donation. Most women surveyed (88%) indicated that they definitely or probably would donate cord blood. Strategies to increase the proportion of African-American blood and cord blood donations may include educating potential donors about the process and benefits of donation to particular patient populations and engaging church leadership in supporting blood and cord blood donations.

Trauma: Spinal Cord Injury.

Science.gov (United States)

Eckert, Matthew J; Martin, Matthew J

2017-10-01

Injuries to the spinal column and spinal cord frequently occur after high-energy mechanisms of injury, or with lower-energy mechanisms, in select patient populations like the elderly. A focused yet complete neurologic examination during the initial evaluation will guide subsequent diagnostic procedures and early supportive measures to help prevent further injury. For patients with injury to bone and/or ligaments, the initial focus should be spinal immobilization and prevention of inducing injury to the spinal cord. Spinal cord injury is associated with numerous life-threatening complications during the acute and long-term phases of care that all acute care surgeons must recognize. Published by Elsevier Inc.

Printing of Titanium implant prototype

International Nuclear Information System (INIS)

Wiria, Florencia Edith; Shyan, John Yong Ming; Lim, Poon Nian; Wen, Francis Goh Chung; Yeo, Jin Fei; Cao, Tong

2010-01-01

Dental implant plays an important role as a conduit of force and stress to flow from the tooth to the related bone. In the load sharing between an implant and its related bone, the amount of stress carried by each of them directly related to their stiffness or modulus. Hence, it is a crucial issue for the implant to have matching mechanical properties, in particular modulus, between the implant and its related bone. Titanium is a metallic material that has good biocompatibility and corrosion resistance. Whilst the modulus of the bulk material is still higher than that of bone, it is the lowest among all other commonly used metallic implant materials, such as stainless steel or cobalt alloy. Hence it is potential to further reduce the modulus of pure Titanium by engineering its processing method to obtain porous structure. In this project, porous Titanium implant prototype is fabricated using 3-dimensional printing. This technique allows the flexibility of design customization, which is beneficial for implant fabrication as tailoring of implant size and shape helps to ensure the implant would fit nicely to the patient. The fabricated Titanium prototype had a modulus of 4.8-13.2 GPa, which is in the range of natural bone modulus. The compressive strength achieved was between 167 to 455 MPa. Subsequent cell culture study indicated that the porous Titanium prototype had good biocompatibility and is suitable for bone cell attachment and proliferation.

Endogenous stem cell proliferation induced by intravenous hedgehog agonist administration after contusion in the adult rat spinal cord.

Science.gov (United States)

Bambakidis, Nicholas C; Horn, Eric M; Nakaji, Peter; Theodore, Nicholas; Bless, Elizabeth; Dellovade, Tammy; Ma, Chiyuan; Wang, Xukui; Preul, Mark C; Coons, Stephen W; Spetzler, Robert F; Sonntag, Volker K H

2009-02-01

Sonic hedgehog (Shh) is a glycoprotein molecule that upregulates the transcription factor Gli1. The Shh protein plays a critical role in the proliferation of endogenous neural precursor cells when directly injected into the spinal cord after a spinal cord injury in adult rodents. Small-molecule agonists of the hedgehog (Hh) pathway were used in an attempt to reproduce these findings through intravenous administration. The expression of Gli1 was measured in rat spinal cord after the intravenous administration of an Hh agonist. Ten adult rats received a moderate contusion and were treated with either an Hh agonist (10 mg/kg, intravenously) or vehicle (5 rodents per group) 1 hour and 4 days after injury. The rats were killed 5 days postinjury. Tissue samples were immediately placed in fixative. Samples were immunohistochemically stained for neural precursor cells, and these cells were counted. Systemic dosing with an Hh agonist significantly upregulated Gli1 expression in the spinal cord (p < 0.005). After spinal contusion, animals treated with the Hh agonist had significantly more nestin-positive neural precursor cells around the rim of the lesion cavity than in vehicle-treated controls (means +/- SDs, 46.9 +/- 12.9 vs 20.9 +/- 8.3 cells/hpf, respectively, p < 0.005). There was no significant difference in the area of white matter injury between the groups. An intravenous Hh agonist at doses that upregulate spinal cord Gli1 transcription also increases the population of neural precursor cells after spinal cord injury in adult rats. These data support previous findings based on injections of Shh protein directly into the spinal cord.

Umbilical cord cell banking-implications for the future

International Nuclear Information System (INIS)

Gunning, Jennifer

2005-01-01

The first successful cord cell transplant to a sibling with Fanconi's anaemia took place 15 years ago. This proven utility of cord blood led to the establishment of cord blood banks both private and public and there are now nearly 100 cord blood banks worldwide. It is estimated that over 200,000 cord blood units (CBU) are held by the private sector and over 160,000 CBU are registered with the largest public cord blood registry. There is a tension between private cord blood banks, which store CBU for autologous or family use, and public banks, which store CBU for unrelated use and the ethics of private cord blood storage has been questioned. But more general ethical questions also arise regarding ownership, consent, confidentiality, costs and quality standards and patenting. In looking at these ethical issues one also needs to look at potential future use of cord blood stem cells. Up until now cord cells have principally been used in the treatment of paediatric blood and immune disorders. Improvements in cell expansion technology will make CBU more appropriate also for treating adults with such disorders. However, it has also been demonstrated that cord blood stem cells have the capacity to differentiate into other types of cells, neuronal, bone, epithelial and muscle which would have a future role to play in cell therapy and regenerative medicine

Spinal cord injury-induced immune deficiency syndrome enhances infection susceptibility dependent on lesion level.

Science.gov (United States)

Brommer, Benedikt; Engel, Odilo; Kopp, Marcel A; Watzlawick, Ralf; Müller, Susanne; Prüss, Harald; Chen, Yuying; DeVivo, Michael J; Finkenstaedt, Felix W; Dirnagl, Ulrich; Liebscher, Thomas; Meisel, Andreas; Schwab, Jan M

2016-03-01

Pneumonia is the leading cause of death after acute spinal cord injury and is associated with poor neurological outcome. In contrast to the current understanding, attributing enhanced infection susceptibility solely to the patient's environment and motor dysfunction, we investigate whether a secondary functional neurogenic immune deficiency (spinal cord injury-induced immune deficiency syndrome, SCI-IDS) may account for the enhanced infection susceptibility. We applied a clinically relevant model of experimental induced pneumonia to investigate whether the systemic SCI-IDS is functional sufficient to cause pneumonia dependent on spinal cord injury lesion level and investigated whether findings are mirrored in a large prospective cohort study after human spinal cord injury. In a mouse model of inducible pneumonia, high thoracic lesions that interrupt sympathetic innervation to major immune organs, but not low thoracic lesions, significantly increased bacterial load in lungs. The ability to clear the bacterial load from the lung remained preserved in sham animals. Propagated immune susceptibility depended on injury of central pre-ganglionic but not peripheral postganglionic sympathetic innervation to the spleen. Thoracic spinal cord injury level was confirmed as an independent increased risk factor of pneumonia in patients after motor complete spinal cord injury (odds ratio = 1.35, P spinal cord injury directly causes increased risk for bacterial infection in mice as well as in patients. Besides obvious motor and sensory paralysis, spinal cord injury also induces a functional SCI-IDS ('immune paralysis'), sufficient to propagate clinically relevant infection in an injury level dependent manner. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Plasma immersion ion implantation: duplex layers from a single process

International Nuclear Information System (INIS)

Hutchings, R.; Collins, G.A.; Tendys, J.

1992-01-01

Plasma immersion ion implantation (PI 3 ) is an alternative non-line-of-sight technique for implanting ions directly from a plasma which surrounds the component to be treated. In contrast to plasma source ion implantation, the PI 3 system uses an inductively coupled r.f. plasma. It is shown that nitrogen can be retained during implantation at elevated temperatures, even for unalloyed steels. This allows controlled diffusion of nitrogen to greater depths, thereby improving the load bearing capacity of the implanted layer. Components can be heated directly, using the energy deposited by the incident ions during the pulsed implantation. The necessary temperature control can be accomplished simply by regulating the frequency and length of the high voltage pulses applied to the component. Chemical depth profiles and microstructural data obtained from H13 tool steel are used to show that PI 3 can, in a single process, effectively produce a duplex subsurface structure. This structure consists of an outer non-equilibrium layer typical of nitrogen implantation (containing in excess of 20 at.% nitrogen) backed by a substantial diffusion zone of much lower nitrogen content. The relationship between implantation temperature and the resultant subsurface microstructure is explored. (orig.)

Implantation damage in heavy gas implanted 4H-SiC

Energy Technology Data Exchange (ETDEWEB)

Jiang, C. [Institut Pprime, CNRS, Université de Poitiers, ENSMA, UPR 3346, Département Physique et Mécanique des Matériaux, Bd Marie et Pierre Curie, BP 30179, 86962 Futuroscope Chasseneuil Cedex (France); Nicolaï, J., E-mail: julien.nicolai@univ-poitiers.fr [Institut Pprime, CNRS, Université de Poitiers, ENSMA, UPR 3346, Département Physique et Mécanique des Matériaux, Bd Marie et Pierre Curie, BP 30179, 86962 Futuroscope Chasseneuil Cedex (France); Declémy, A. [Institut Pprime, CNRS, Université de Poitiers, ENSMA, UPR 3346, Département Physique et Mécanique des Matériaux, Bd Marie et Pierre Curie, BP 30179, 86962 Futuroscope Chasseneuil Cedex (France); Gilabert, E. [Centre d’Etude Nucléaire de Bordeaux-Gradignan, 33175 Gradignan Cedex (France); Beaufort, M.-F.; Barbot, J.-F. [Institut Pprime, CNRS, Université de Poitiers, ENSMA, UPR 3346, Département Physique et Mécanique des Matériaux, Bd Marie et Pierre Curie, BP 30179, 86962 Futuroscope Chasseneuil Cedex (France)

2016-05-01

Single crystals of SiC were implanted with heavy inert gases (Xe, Ar) at elevated temperatures (300–800 °C) and for a large range of fluence (1 × 10{sup 12}–1 × 10{sup 15} ions cm{sup −2}). Thermodesorption measurements suggest that gas is trapped by implantation-induced vacancy-type defects impeding any gas diffusion. The damage accumulation versus dose was studied through the tensile elastic strain determined by using X-ray diffraction. Results show that at low dose the strain is predictable via a thermally activated direct impact model. The low thermal activation energy at saturation suggests a dynamic recovery process dominated by the migration of interstitial-type defects as its relaxation during post thermal annealing. As compared with light-gas implantation the heavy-gas to defect ratio is low enhancing the formation of strongly perturbed zones rather than the formation of bubble precursors.

Remote programming of cochlear implants: a telecommunications model.

Science.gov (United States)

McElveen, John T; Blackburn, Erin L; Green, J Douglas; McLear, Patrick W; Thimsen, Donald J; Wilson, Blake S

2010-09-01

Evaluate the effectiveness of remote programming for cochlear implants. Retrospective review of the cochlear implant performance for patients who had undergone mapping and programming of their cochlear implant via remote connection through the Internet. Postoperative Hearing in Noise Test and Consonant/Nucleus/Consonant word scores for 7 patients who had undergone remote mapping and programming of their cochlear implant were compared with the mean scores of 7 patients who had been programmed by the same audiologist over a 12-month period. Times required for remote and direct programming were also compared. The quality of the Internet connection was assessed using standardized measures. Remote programming was performed via a virtual private network with a separate software program used for video and audio linkage. All 7 patients were programmed successfully via remote connectivity. No untoward patient experiences were encountered. No statistically significant differences could be found in comparing postoperative Hearing in Noise Test and Consonant/Nucleus/Consonant word scores for patients who had undergone remote programming versus a similar group of patients who had their cochlear implant programmed directly. Remote programming did not require a significantly longer programming time for the audiologist with these 7 patients. Remote programming of a cochlear implant can be performed safely without any deterioration in the quality of the programming. This ability to remotely program cochlear implant patients gives the potential to extend cochlear implantation to underserved areas in the United States and elsewhere.

Tolerance of rat spinal cord to continuous interstitial irradiation

International Nuclear Information System (INIS)

Pop, Lucas A.M.; Plas, Mirjam van der; Ruifrok, Arnout C.C.; Schalkwijk, Lia J.M.; Hanssen, Alex E.J.; Kogel, Albert J. van der

1998-01-01

Purpose: To study the kinetics of repair in rat spinal cord during continuous interstitial irradiation at different dose rates and to investigate the impact of a rapid dose fall off over the spinal cord thickness. Material and Methods: Two parallel catheters were inserted on each side of the vertebral bodies from the level of T 10 to L 4 . These catheters were afterloaded with two 192 Ir- wires of 4 cm length each (activity 1 - 10 mCi/cm) or connected to the HDR- microSelectron. Experiments have been carried out to obtain complete dose response curves at 7 different dose rates: 0.53, 0.90, 1.64, 2.56, 4.4, 9.9 and 120 Gy/h. Paralysis of the hindlegs after 5 - 6 months and histopathological examination of the spinal cord of each animal were used as experimental endpoints. Results: The distribution of the histological damage was a good reflection of the rapid dose fall - off over the spinal cord, with white matter necrosis or demyelination predominantly seen in the dorsal tracts of the spinal cord or dorsal roots. With each reduction of the dose rate, spinal cord tolerance was significantly increased, with a maximum dose rate factor of 4.3 if the dose rate was reduced from 120 Gy/h to 0.53 Gy/h (ED 50 of 17.3 Gy and 75.0 Gy, respectively). Estimates of the repair parameters using different types of analysis are presented. For the direct analysis the best fit of the data was obtained if a biexponential function for repair was used. For the 100% dose prescribed at the ventral side of the spinal cord the (α(β)) ratio is 1.8 Gy (0.8 - 2.8) and two components of repair are observed: a slow component of repair of 2.44 h (1.18 - ∞) and a fast component of 0.15 h (0.02 - ∞). The proportion of the damage repaired with the slow component is 0.59 (0.18 - 1). For the maximum of 150% of the prescribed dose at the dorsal side of the spinal cord the (α(β)) ratio is 2.7 Gy (1.5 - 4.4); the two components for the kinetics of repair remain the same. Conclusions: Spinal cord

The oblique cord of the forearm in man.

Science.gov (United States)

Tubbs, R Shane; O'Neil, James T; Key, Christopher D; Zarzour, Jessica G; Fulghum, Sarah B; Kim, Eugenia J; Lyerly, Michael J; Shoja, Mohammadali M; George Salter, E; Jerry Oakes, W

2007-05-01

There is minimal and often conflicting data in the literature regarding the oblique cord of the forearm. The current study seeks to elucidate further the anatomy of this structure of the upper extremity. In adult cadavers, the oblique cord was observed for and, when found, measurements were made of it. Ranges of motion were carried out while observation of the oblique cord was made. An oblique cord was found on 52.6% of sides. Gantzer's muscle was found on 55% of sides and, when present, had attachment into the oblique cord on five sides. The oblique cord was present on 13 sides with a Gantzer's muscle. Of the 20 sides with an oblique cord, no Gantzer's muscle was found on 10. The mean length of the oblique cord was 3.4 cm. In the majority of specimens, this cord tapered from proximal to distal. The proximal, middle, and distal widths of this structure had means 9, 7, and 4 mm, respectively. The oblique cord was found to travel approximately 45 degrees from a line drawn through the ulna and more or less traveled perpendicular to the insertion site of the bicipital tendon. This ligament was lax in the neutral position and with pronation became lax in all specimens. The oblique cord progressively became taut with increased supination from the neutral position and was maximally taut with the forearm fully supinated. Tautness of this cord was also found with distal distraction of the radius. Following the transection of the oblique cord, no discernable difference was observed in regard to maximal supination of the forearm or distal distraction of the radius. No obvious instability of the proximal forearm was found following transection of the oblique cord. Functionally, although the oblique cord may resist supination, it is unlikely that this structure affords significant stability to the proximal forearm, as it was often absent, of a very small caliber, and based on our observations, following its transection, the amount of supination of the forearm did not increase

Preclinical Evaluation of the Immunomodulatory Properties of Cardiac Adipose Tissue Progenitor Cells Using Umbilical Cord Blood Mesenchymal Stem Cells: A Direct Comparative Study

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Isaac Perea-Gil

2015-01-01

Full Text Available Cell-based strategies to regenerate injured myocardial tissue have emerged over the past decade, but the optimum cell type is still under scrutiny. In this context, human adult epicardial fat surrounding the heart has been characterized as a reservoir of mesenchymal-like progenitor cells (cardiac ATDPCs with potential clinical benefits. However, additional data on the possibility that these cells could trigger a deleterious immune response following implantation are needed. Thus, in the presented study, we took advantage of the well-established low immunogenicity of umbilical cord blood-derived mesenchymal stem cells (UCBMSCs to comparatively assess the immunomodulatory properties of cardiac ATDPCs in an in vitro allostimulatory assay using allogeneic mature monocyte-derived dendritic cells (MDDCs. Similar to UCBMSCs, increasing amounts of seeded cardiac ATDPCs suppressed the alloproliferation of T cells in a dose-dependent manner. Secretion of proinflammatory cytokines (IL6, TNFα, and IFNγ was also specifically modulated by the different numbers of cardiac ATDPCs cocultured. In summary, we show that cardiac ATDPCs abrogate T cell alloproliferation upon stimulation with allogeneic mature MDDCs, suggesting that they could further regulate a possible harmful immune response in vivo. Additionally, UCBMSCs can be considered as valuable tools to preclinically predict the immunogenicity of prospective regenerative cells.

Diffusion tensor tractography of normal and compressed spinal cord: a preliminary study at 3.0 T MR

International Nuclear Information System (INIS)

Wang Wei; Chang Shixin; Hao Nanxin; Du Yushan; Wang Yibin; Zong Genlin; Cao Kaiming; Lu Jianping; Zhao Cheng; Qin Wen

2007-01-01

Objective: To study the feasibility and clinical values of diffusion tensor tractography (DTT) in the spinal cord at 3.0 T MR. Methods: Forty patients with spinal cord compression including cervical cord herniation and cervical spondylosis (30 cases), tumors in spinal canal (9 cases) and old injury in cervical vertebrae (1 cases) and 20 healthy volunteers participated in this study. Single-shot spin- echo echo-planar diffusion tensor sequence for tractography of the spinal cord was performed. The fibers of spinal cord were visualized by using fiber tracking software. Results: On the DTT maps, the normal spinal cord was depicted as a fiber tract showing color-encoded cephalocaudally, which indicated anisotropy in the cephalocaudal direction. By setting two ROI, the main spinal cord fiber tracts, such as corticospinal or spinothalamic tract, were visualized. The tracts from two sides of the brain did not completely cross. It was asymmetric in the number of tracts on the two sides in most normal subjects (8/10). The tracts of all patients with cord compression were seen oppressed or damaged in different degrees. The DTT in patients with cervical spondylosis and extramedullary-intradural neurolemmoma demonstrated that tracts were oppressed but not damaged. The DTT in one ependymoma showed that tract was markedly compressed and slightly damaged. Conclusion: DTT is a promising tool for demonstrating the spinal cord tracts and abnormalities, can provide useful information for the localization of compression and evaluation of the impairment extent on the white matter tracts of the spinal cord. (authors)

Implantable cardioverter defibrillator specific rehabilitation improves health cost outcomes

DEFF Research Database (Denmark)

Berg, Selina Kikkenborg; Zwisler, Ann-Dorthe; Koch, Mette Bjerrum

2015-01-01

OBJECTIVE: The Copenhagen Outpatient ProgrammE - implantable cardioverter defibrillator (COPE-ICD) trial included patients with implantable cardioverter defibrillators in a randomized controlled trial of rehabilitation. After 6-12 months significant differences were found in favour of the rehabil...... was -6,789 USD/-5,593 Euro in favour of rehabilitation. CONCLUSION: No long-term health outcome benefits were found for the rehabilitation programme. However, the rehabilitation programme resulted in a reduction in total attributable direct costs....... of the rehabilitation group for exercise capacity, general and mental health. The aim of this paper is to explore the long-term health effects and cost implications associated with the rehabilitation programme; more specifically, (i) to compare implantable cardioverter defibrillator therapy history and mortality...... between rehabilitation and usual care groups; (ii) to examine the difference between rehabilitation and usual care groups in terms of time to first admission; and (iii) to determine attributable direct costs. METHODS: Patients with first-time implantable cardioverter defibrillator implantation (n = 196...

Implantation damage in silicon devices

International Nuclear Information System (INIS)

Nicholas, K.H.

1977-01-01

Ion implantation, is an attractive technique for producing doped layers in silicon devices but the implantation process involves disruption of the lattice and defects are formed, which can degrade device properties. Methods of minimizing such damage are discussed and direct comparisons made between implantation and diffusion techniques in terms of defects in the final devices and the electrical performance of the devices. Defects are produced in the silicon lattice during implantation but they are annealed to form secondary defects even at room temperature. The annealing can be at a low temperature ( 0 C) when migration of defects in silicon in generally small, or at high temperature when they can grow well beyond the implanted region. The defect structures can be complicated by impurity atoms knocked into the silicon from surface layers by the implantation. Defects can also be produced within layers on top of the silicon and these can be very important in device fabrication. In addition to affecting the electrical properties of the final device, defects produced during fabrication may influence the chemical properties of the materials. The use of these properties to improve devices are discussed as well as the degradation they can cause. (author)

Pregnancy Complications: Umbilical Cord Abnormalities

Science.gov (United States)

... Umbilical cord abnormalities Umbilical cord abnormalities Now playing: E-mail to a friend Please fill in all fields. ... blood supply) to the baby. The two arteries transport waste from the baby to the placenta (where ...

Additive manufacturing technologies of porous metal implants

Directory of Open Access Journals (Sweden)

Yang Quanzhan

2014-06-01

Full Text Available Biomedical metal materials with good corrosion resistance and mechanical properties are widely used in orthopedic surgery and dental implant materials, but they can easily cause stress shielding due to the significant difference in elastic modulus between the implant and human bones. The elastic modulus of porous metals is lower than that of dense metals. Therefore, it is possible to adjust the pore parameters to make the elastic modulus of porous metals match or be comparable with that of the bone tissue. At the same time, the open porous metals with pores connected to each other could provide the structural condition for bone ingrowth, which is helpful in strengthening the biological combination of bone tissue with the implants. Therefore, the preparation technologies of porous metal implants and related research have been drawing more and more attention due to the excellent features of porous metals. Selective laser melting (SLM and electron beam melting technology (EBM are important research fields of additive manufacturing. They have the advantages of directly forming arbitrarily complex shaped metal parts which are suitable for the preparation of porous metal implants with complex shape and fine structure. As new manufacturing technologies, the applications of SLM and EBM for porous metal implants have just begun. This paper aims to understand the technology status of SLM and EBM, the research progress of porous metal implants preparation by using SLM and EBM, and the biological compatibility of the materials, individual design and manufacturing requirements. The existing problems and future research directions for porous metal implants prepared by SLM and EBM methods are discussed in the last paragraph.

Epidural spinal cord stimulation for neuropathic pain: a neurosurgical multicentric Italian data collection and analysis.

Science.gov (United States)

Colombo, Elena Virginia; Mandelli, Carlo; Mortini, Pietro; Messina, Giuseppe; De Marco, Nicola; Donati, Roberto; Irace, Claudio; Landi, Andrea; Lavano, Angelo; Mearini, Massimo; Podetta, Stefano; Servello, Domenico; Zekaj, Edvin; Valtulina, Carlo; Dones, Ivano

2015-04-01

Spinal cord stimulation (SCS) is a technique used worldwide to treat several types of chronic neuropathic pain refractory to any conservative treatment. The aim of this data collection is to enforce evidence of SCS effectiveness on neuropathic chronic pain reported in the literature and to speculate on the usefulness of the trial period in determining the long-term efficacy. Moreover, the very low percentage of undesired side effects and complications reported in our case series suggests that all implants should be performed by similarly well-trained and experienced professionals. A multicentric data collection on a common database from 11 Italian neurosurgical departments started 3 years ago. Two different types of electrodes (paddle or percutaneous leads) were used. Of 122 patients, 73 % (N = 89) were submitted to a trial period, while the remaining patients underwent the immediate permanent implant (N = 33). Statistical comparisons of continuous variables between groups were performed. Most of the patients (80 %) had predominant pain to their lower limbs, while only 17 % of patients had prevalent axial pain. Significant reduction in pain, as measured by variation in visual analogue scale (VAS) score, was observed at least 1 year after implantation in 63.8 % of the cases, 59.5 % of patients who underwent a test trial and 71.4 % of patients who underwent permanent implant at once. No statistical differences were found between the lower-limb pain group and the axial pain group. No relevant differences in long-term outcomes were observed in previously tested patients compared with patients implanted at once. Through this analysis we hope to recruit new centres, to give more scientific value to our results.

Diffusion tensor imaging in spinal cord injury

International Nuclear Information System (INIS)

Kamble, Ravindra B; Venkataramana, Neelam K; Naik, Arun L; Rao, Shailesh V

2011-01-01

To assess the feasibility of spinal tractography in patients of spinal cord injury vs a control group and to compare fractional anisotropy (FA) values between the groups. Diffusion tensor imaging (DTI) was performed in the spinal cord of 29 patients (18 patients and 11 controls). DTI was done in the cervical region if the cord injury was at the dorsal or lumbar region and in the conus region if cord injury was in the cervical or dorsal region. FA was calculated for the patients and the controls and the values were compared. The mean FA value was 0.550±0.09 in the control group and 0.367±0.14 in the patients; this difference was statistically significant (P=0.001). Spinal tractography is a feasible technique to assess the extent of spinal cord injury by FA, which is reduced in patients of spinal cord injury, suggesting possible Wallerian degeneration. In future, this technique may become a useful tool for assessing cord injury patients after stem cell therapy, with improvement in FA values indicating axonal regeneration

Pain Relief in CRPS-II after Spinal Cord and Motor Cortex Simultaneous Dual Stimulation.

Science.gov (United States)

Lopez, William Oc; Barbosa, Danilo C; Teixera, Manoel J; Paiz, Martin; Moura, Leonardo; Monaco, Bernardo A; Fonoff, Erich T

2016-05-01

We describe a case of a 30-year-old woman who suffered a traumatic injury of the right brachial plexus, developing severe complex regional pain syndrome type II (CRPS-II). After clinical treatment failure, spinal cord stimulation (SCS) was indicated with initial positive pain control. However, after 2 years her pain progressively returned to almost baseline intensity before SCS. Additional motor cortex electrode implant was then proposed as a rescue therapy and connected to the same pulse generator. This method allowed simultaneous stimulation of the motor cortex and SCS in cycling mode with independent stimulation parameters in each site. At 2 years follow-up, the patient reported sustained improvement in pain with dual stimulation, reduction of painful crises, and improvement in quality of life. The encouraging results in this case suggests that this can be an option as add-on therapy over SCS as a possible rescue therapy in the management of CRPS-II. However, comparative studies must be performed in order to determine the effectiveness of this therapy. Chronic neuropathic pain, Complex regional pain syndrome Type II, brachial plexus injury, motor cortex stimulation, spinal cord stimulation.

Characterizing the location of spinal and vertebral levels in the human cervical spinal cord.

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Cadotte, D W; Cadotte, A; Cohen-Adad, J; Fleet, D; Livne, M; Wilson, J R; Mikulis, D; Nugaeva, N; Fehlings, M G

2015-04-01

Advanced MR imaging techniques are critical to understanding the pathophysiology of conditions involving the spinal cord. We provide a novel, quantitative solution to map vertebral and spinal cord levels accounting for anatomic variability within the human spinal cord. For the first time, we report a population distribution of the segmental anatomy of the cervical spinal cord that has direct implications for the interpretation of advanced imaging studies most often conducted across groups of subjects. Twenty healthy volunteers underwent a T2-weighted, 3T MRI of the cervical spinal cord. Two experts marked the C3-C8 cervical nerve rootlets, C3-C7 vertebral bodies, and pontomedullary junction. A semiautomated algorithm was used to locate the centerline of the spinal cord and measure rostral-caudal distances from a fixed point in the brain stem, the pontomedullary junction, to each of the spinal rootlets and vertebral bodies. Distances to each location were compared across subjects. Six volunteers had 2 additional scans in neck flexion and extension to measure the effects of patient positioning in the scanner. We demonstrated that substantial variation exists in the rostral-caudal position of spinal cord segments among individuals and that prior methods of predicting spinal segments are imprecise. We also show that neck flexion or extension has little effect on the relative location of vertebral-versus-spinal levels. Accounting for spinal level variation is lacking in existing imaging studies. Future studies should account for this variation for accurate interpretation of the neuroanatomic origin of acquired MR signals. © 2015 by American Journal of Neuroradiology.

Cost-effectiveness of private umbilical cord blood banking.

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Kaimal, Anjali J; Smith, Catherine C; Laros, Russell K; Caughey, Aaron B; Cheng, Yvonne W

2009-10-01

To investigate the cost-effectiveness of private umbilical cord blood banking. A decision-analytic model was designed comparing private umbilical cord blood banking with no umbilical cord blood banking. Baseline assumptions included a cost of $3,620 for umbilical cord blood banking and storage for 20 years, a 0.04% chance of requiring an autologous stem cell transplant, a 0.07% chance of a sibling requiring an allogenic stem cell transplant, and a 50% reduction in risk of graft-versus-host disease if a sibling uses banked umbilical cord blood. Private cord blood banking is not cost-effective because it cost an additional $1,374,246 per life-year gained. In sensitivity analysis, if the cost of umbilical cord blood banking is less than $262 or the likelihood of a child needing a stem cell transplant is greater than 1 in 110, private umbilical cord blood banking becomes cost-effective. Currently, private umbilical cord blood banking is cost-effective only for children with a very high likelihood of needing a stem cell transplant. Patients considering private blood banking should be informed of the remote likelihood that a unit will be used for a child or another family member. III.

Malignant spinal cord compression in cancer patients may be mimicked by a primary spinal cord tumour.

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Mohammadianpanah, M; Vasei, M; Mosalaei, A; Omidvari, S; Ahmadloo, N

2006-12-01

Although it is quite rare, second primary neoplasms in cancer patients may present with the signs and symptoms of malignant spinal cord compression. Primary spinal cord tumours in the cancer patients may be deceptive and considered as the recurrent first cancer. Therefore, it should be precisely differentiated and appropriately managed. We report such a case of intramedullary ependymoma of the cervical spinal cord mimicking metatstatic recurrent lymphoma and causing cord compression. A 50-year-old man developed intramedullary ependymoma of the cervical spinal cord 1.5 years following chemoradiation for Waldeyer's ring lymphoma. He presented with a 2-month history of neck pain, progressive upper- and lower-extremity numbness and weakness, and bowel and bladder dysfunction. Magnetic resonance imaging revealed an intramedullary expansive lesion extending from C4 to C6 levels of the cervical spinal cord. The clinical and radiological findings were suggestive of malignant process. A comprehensive investigation failed to detect another site of disease. He underwent operation, and the tumour was subtotally resected. The patient's neurological deficits improved subsequently. The development of the intramedullary ependymoma following treating lymphoma has not been reported. We describe the clinical, radiological and pathological findings of this case and review the literature.

Implant Angle Monitor System of MC3-II

International Nuclear Information System (INIS)

Sato, Fumiaki; Sano, Makoto; Nakaoka, Hiroaki; Fujii, Yoshito; Kudo, Tetuya; Nakanishi, Makoto; Koike, Masazumi; Fujino, Yasushi

2008-01-01

Precise implant angle control is required for the latest generation of ion implanters to meet further shrink semiconductor device requirements. Especially, the highest angle accuracy is required for Halo implant process of Logic devices. The Halo implant angle affects the device performance, because slight differences of beam divergence change the overlap profile towards the extension. Additionally, twist angle accuracy is demanded in case of channeling angle implant. Therefore monitoring beam angles and wafer twist angles is important. A new monitoring system for the MC3-II, SEN Corp.'s single wafer type medium current implanter has been developed. This paper describes the angle control performance and monitoring system of the MC3-II. For the twist angle control, we developed a wafer notch angle monitor. The system monitors the wafer notch image on the platen. And the notch angle variation is calculated by using image processing method. It is also able to adjust the notch angle according to the angle error. For the tilt angle control, we developed a vertical beam profile monitor. The monitor system can detect beam profile of vertical directions with horizontally scanning beam. It also measures beam angles of a tilt direction to a wafer. The system configuration and sample beam data are presented.

Topologically preserving straightening of spinal cord MRI.

Science.gov (United States)

De Leener, Benjamin; Mangeat, Gabriel; Dupont, Sara; Martin, Allan R; Callot, Virginie; Stikov, Nikola; Fehlings, Michael G; Cohen-Adad, Julien

2017-10-01

To propose a robust and accurate method for straightening magnetic resonance (MR) images of the spinal cord, based on spinal cord segmentation, that preserves spinal cord topology and that works for any MRI contrast, in a context of spinal cord template-based analysis. The spinal cord curvature was computed using an iterative Non-Uniform Rational B-Spline (NURBS) approximation. Forward and inverse deformation fields for straightening were computed by solving analytically the straightening equations for each image voxel. Computational speed-up was accomplished by solving all voxel equation systems as one single system. Straightening accuracy (mean and maximum distance from straight line), computational time, and robustness to spinal cord length was evaluated using the proposed and the standard straightening method (label-based spline deformation) on 3T T 2 - and T 1 -weighted images from 57 healthy subjects and 33 patients with spinal cord compression due to degenerative cervical myelopathy (DCM). The proposed algorithm was more accurate, more robust, and faster than the standard method (mean distance = 0.80 vs. 0.83 mm, maximum distance = 1.49 vs. 1.78 mm, time = 71 vs. 174 sec for the healthy population and mean distance = 0.65 vs. 0.68 mm, maximum distance = 1.28 vs. 1.55 mm, time = 32 vs. 60 sec for the DCM population). A novel image straightening method that enables template-based analysis of quantitative spinal cord MRI data is introduced. This algorithm works for any MRI contrast and was validated on healthy and patient populations. The presented method is implemented in the Spinal Cord Toolbox, an open-source software for processing spinal cord MRI data. 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2017;46:1209-1219. © 2017 International Society for Magnetic Resonance in Medicine.

Reduced intensity haplo plus single cord transplant compared to double cord transplant: improved engraftment and graft-versus-host disease-free, relapse-free survival

Science.gov (United States)

van Besien, Koen; Hari, Parameswaran; Zhang, Mei-Jie; Liu, Hong-Tao; Stock, Wendy; Godley, Lucy; Odenike, Olatoyosi; Larson, Richard; Bishop, Michael; Wickrema, Amittha; Gergis, Usama; Mayer, Sebastian; Shore, Tsiporah; Tsai, Stephanie; Rhodes, Joanna; Cushing, Melissa M.; Korman, Sandra; Artz, Andrew

2016-01-01

Umbilical cord blood stem cell transplants are commonly used in adults lacking HLA-identical donors. Delays in hematopoietic recovery contribute to mortality and morbidity. To hasten recovery, we used co-infusion of progenitor cells from a partially matched related donor and from an umbilical cord blood graft (haplo-cord transplant). Here we compared the outcomes of haplo-cord and double-cord transplants. A total of 97 adults underwent reduced intensity conditioning followed by haplo-cord transplant and 193 patients received reduced intensity conditioning followed by double umbilical cord blood transplantation. Patients in the haplo-cord group were more often from minority groups and had more advanced malignancy. Haplo-cord recipients received fludarabine-melphalan-anti-thymocyte globulin. Double umbilical cord blood recipients received fludarabine-cyclophosphamide and low-dose total body irradiation. In a multivariate analysis, haplo-cord had faster neutrophil (HR=1.42, P=0.007) and platelet (HR=2.54, Pdisease (HR=0.26, Pdisease (HR=0.06, Pdisease-free, relapse-free survival was superior with haplo-cord (HR 0.63, P=0.002) but not overall survival (HR=0.97, P=0.85). Haplo-cord transplantation using fludarabine-melphalan-thymoglobulin conditioning hastens hematopoietic recovery with a lower risk of relapse relative to double umbilical cord blood transplantation using the commonly used fludarabine-cyclophosphamide-low-dose total body irradiation conditioning. Graft-versus-host disease-free and relapse-free survival is significantly improved. Haplo-cord is a readily available graft source that improves outcomes and access to transplant for those lacking HLA-matched donors. Trials registered at clinicaltrials.gov identifiers 00943800 and 01810588. PMID:26869630

Study of the relationship between the indication rod of stent on implant CT and the real path of implant fixture insertion considering residual ridge

International Nuclear Information System (INIS)

Kim, Do Hoon; Heo, Min Suk; Lee, Sam Sun; Oh, Sung Ook; Choi, Soon Chul; Choi, Hang Moon; Jeon, In Seong

2003-01-01

To assess the relationship between the direction of the indicating rod of the radiographic stent for ideal prosthetic design and the actual possible path of implant fixture placement when residual ridge resorption is considered. The study materials considered of 326 implant sites (male 214 cases and female 112 cases) from a total of 106 patients (male 65 patients and female 41 patients) who desired implant prostheses. Computed tomography of patients were taken and reformatted using ToothPix software. Bony defects, bony sclerosis, the change of the direction of indicating rod, and root proximity of the adjacent teeth were examined on the CT-derived images. The rate of the irregular crestal cortex was relatively high on premolar and molar area of maxilla. Mandibular molar area showed relatively high rate of focal sclerosis on the area of implant fixture insertion. The position of the including rods were relatively acceptable on the molar areas of both jaws. However, the position of the indicating rods should be shifted to buccal side with lingual rotation of the apical end on maxillary anterior teeth and premolar area. Clinically determined rod direction and position of the indicating rod for implant placement was not always acceptable for insertion according to the reformatted CT images. The pre-operative treatment plan for implant should be determined carefully, considering the state of the alveolar bone using the reformatted CT images.

A 60 keV implanter for metals

International Nuclear Information System (INIS)

Leutenecker, R.; Ryssel, H.; Zeller, K.-H.; Spoehrle, H.P.

1985-01-01

The design and preliminary performance data of a 60 keV high current implanter for the implantation of non-separated ion beams into metals are described. The target chamber accepts samples up to 70 cm in diameter and is equipped with holders to implant ball bearings, axles and other components which have to be rotated during implantation. Samples are mounted on a rugged table which can move up to 35 kg for +-35 cm in the x and y directions. The implanter, including the vacuum system, is completely computer controlled. The ion source is equipped with an oven having a maximum temperature of 1200 0 C and can deliver ion beams of nitrogen as well as different metal ions such as tin and silver with currents up to 10 mA. (Auth.)

Analysis of induced electrical currents from magnetic field coupling inside implantable neurostimulator leads

Directory of Open Access Journals (Sweden)

Seidman Seth J

2011-10-01

Full Text Available Abstract Background Over the last decade, the number of neurostimulator systems implanted in patients has been rapidly growing. Nearly 50, 000 neurostimulators are implanted worldwide annually. The most common type of implantable neurostimulators is indicated for pain relief. At the same time, commercial use of other electromagnetic technologies is expanding, making electromagnetic interference (EMI of neurostimulator function an issue of concern. Typically reported sources of neurostimulator EMI include security systems, metal detectors and wireless equipment. When near such sources, patients with implanted neurostimulators have reported adverse events such as shock, pain, and increased stimulation. In recent in vitro studies, radio frequency identification (RFID technology has been shown to inhibit the stimulation pulse of an implantable neurostimulator system during low frequency exposure at close distances. This could potentially be due to induced electrical currents inside the implantable neurostimulator leads that are caused by magnetic field coupling from the low frequency identification system. Methods To systematically address the concerns posed by EMI, we developed a test platform to assess the interference from coupled magnetic fields on implantable neurostimulator systems. To measure interference, we recorded the output of one implantable neurostimulator, programmed for best therapy threshold settings, when in close proximity to an operating low frequency RFID emitter. The output contained electrical potentials from the neurostimulator system and those induced by EMI from the RFID emitter. We also recorded the output of the same neurostimulator system programmed for best therapy threshold settings without RFID interference. Using the Spatially Extended Nonlinear Node (SENN model, we compared threshold factors of spinal cord fiber excitation for both recorded outputs. Results The electric current induced by low frequency RFID emitter

Risk factors in iatrogenic spinal cord injury.

Science.gov (United States)

Montalva-Iborra, A; Alcanyis-Alberola, M; Grao-Castellote, C; Torralba-Collados, F; Giner-Pascual, M

2017-09-01

In the last years, there has been a change in the aetiology of spinal cord injury. There has been an increase in the number of elderly patients with spinal cord injuries caused by diseases or medical procedures. The aim of this study is to investigate the frequency of the occurrence of iatrogenic spinal cord injury in our unit. The secondary aim is to study what variables can be associated with a higher risk of iatrogenesis. A retrospective, descriptive, observational study of patients with acute spinal cord injury admitted from June 2009 to May 2014 was conducted. The information collected included the patient age, aetiology, neurological level and grade of injury when admitted and when discharged, cardiovascular risk factors, a previous history of depression and any prior treatment with anticoagulant or antiplatelet drugs. We applied a logistic regression. The grade of statistical significance was established as Pinjury was the thoracic level (48%). The main aetiology of spinal cord injury caused by iatrogenesis was surgery for degenerative spine disease, in patients under the age of 30 were treated with intrathecal chemotherapy. Iatrogenic spinal cord injury is a frequent complication. A statistically significant association between a patient history of depression and iatrogenic spinal cord injury was found as well as with anticoagulant and antiplatelet drug use prior to iatrogenic spinal cord injury.

Stereo imaging and cytocompatibility of a model dental implant surface formed by direct laser fabrication.

Science.gov (United States)

Mangano, Carlo; Raspanti, Mario; Traini, Tonino; Piattelli, Adriano; Sammons, Rachel

2009-03-01

Direct laser fabrication (DLF) allows solids with complex geometry to be produced by sintering metal powder particles in a focused laser beam. In this study, 10 Ti6Al4V alloy model dental root implants were obtained by DLF, and surface characterization was carried out using stereo scanning electron microscopy to produce 3D reconstructions. The surfaces were extremely irregular, with approximately 100 microm deep, narrow intercommunicating crevices, shallow depressions and deep, rounded pits of widely variable shape and size, showing ample scope for interlocking with the host bone. Roughness parameters were as follows: R(t), 360.8 microm; R(z), 358.4 microm; R(a), 67.4 microm; and R(q), 78.0 microm. Disc specimens produced by DLF with an identically prepared surface were used for biocompatibility studies with rat calvarial osteoblasts: After 9 days, cells had attached and spread on the DLF surface, spanning across the crevices, and voids. Cell density was similar to that on a commercial rough microtextured surface but lower than on commercial smooth machined and smooth-textured grit-blasted, acid-etched surfaces. Human fibrin clot extension on the DLF surface was slightly improved by inorganic acid etching to increase the microroughness. With further refinements, DLF could be an economical means of manufacturing implants from titanium alloys. (c) 2008 Wiley Periodicals, Inc.

SCT: Spinal Cord Toolbox, an open-source software for processing spinal cord MRI data.

Science.gov (United States)

De Leener, Benjamin; Lévy, Simon; Dupont, Sara M; Fonov, Vladimir S; Stikov, Nikola; Louis Collins, D; Callot, Virginie; Cohen-Adad, Julien

2017-01-15

For the past 25 years, the field of neuroimaging has witnessed the development of several software packages for processing multi-parametric magnetic resonance imaging (mpMRI) to study the brain. These software packages are now routinely used by researchers and clinicians, and have contributed to important breakthroughs for the understanding of brain anatomy and function. However, no software package exists to process mpMRI data of the spinal cord. Despite the numerous clinical needs for such advanced mpMRI protocols (multiple sclerosis, spinal cord injury, cervical spondylotic myelopathy, etc.), researchers have been developing specific tools that, while necessary, do not provide an integrative framework that is compatible with most usages and that is capable of reaching the community at large. This hinders cross-validation and the possibility to perform multi-center studies. In this study we introduce the Spinal Cord Toolbox (SCT), a comprehensive software dedicated to the processing of spinal cord MRI data. SCT builds on previously-validated methods and includes state-of-the-art MRI templates and atlases of the spinal cord, algorithms to segment and register new data to the templates, and motion correction methods for diffusion and functional time series. SCT is tailored towards standardization and automation of the processing pipeline, versatility, modularity, and it follows guidelines of software development and distribution. Preliminary applications of SCT cover a variety of studies, from cross-sectional area measures in large databases of patients, to the precise quantification of mpMRI metrics in specific spinal pathways. We anticipate that SCT will bring together the spinal cord neuroimaging community by establishing standard templates and analysis procedures. Copyright © 2016 Elsevier Inc. All rights reserved.

[Impact of animal-assisted intervention on rehabilitation of patients with spinal cord injury].

Science.gov (United States)

Zsoldos, Amanda; Sátori, Agnes; Zana, Agnes

2014-09-28

The animal-assisted programs represent an interdisciplinary approach. They can be integrated into preventive, therapeutic and rehabilitative processes as complementary methods. The aim of the study was to promote the psychological adaptation and social reintegration of patients who suffered spinal cord injury, as well as reducing depression and feelings of isolation caused by the long hospitalization. The hypothesis of the authors was that the animal-assisted intervention method can be effectively inserted into the rehabilitation process of individuals with spinal cord injury as complementary therapy. 15 adults with spinal cord injury participated in the five-week program, twice a week. Participants first filled out a questionnaire on socio-demographics, and after completion of the program they participated in a short, directed interview with open questions. During the field-work, after observing the participants, qualitative data analysis was performed. The results suggest that the therapeutic animal induced a positive effect on the emotional state of the patients. Participants acquired new skills and knowledge, socialization and group cohesion had been improved. The authors conclude that the animal-assisted activity complemented by therapeutic elements can be beneficial in patients undergoing spinal cord injury rehabilitation and that knowledge obtained from the study can be helpful in the development of a future animal-assisted therapy program for spinal cord injury patients.

Improvement of myocardial perfusion reserve detected by cardiovascular magnetic resonance after direct endomyocardial implantation of autologous bone marrow cells in patients with severe coronary artery disease

Directory of Open Access Journals (Sweden)

Lau Chu-Pak

2010-01-01

Full Text Available Abstract Background Recent studies suggested that bone marrow (BM cell implantation in patients with severe chronic coronary artery disease (CAD resulted in modest improvement in symptoms and cardiac function. This study sought to investigate the functional changes that occur within the chronic human ischaemic myocardium after direct endomyocardial BM cells implantation by cardiovascular magnetic resonance (CMR. Methods and Results We compared the interval changes of left ventricular ejection fraction (LVEF, myocardial perfusion reserve and the extent of myocardial scar by using late gadolinium enhancement CMR in 12 patients with severe CAD. CMR was performed at baseline and at 6 months after catheter-based direct endomyocardial autologous BM cell (n = 12 injection to viable ischaemic myocardium as guided by electromechanical mapping. In patients randomized to receive BM cell injection, there was significant decrease in percentage area of peri-infarct regions (-23.6%, P = 0.04 and increase in global LVEF (+9.0%, P = 0.02, the percentage of regional wall thickening (+13.1%, P= 0.04 and MPR (+0.25%, P = 0.03 over the target area at 6-months compared with baseline. Conclusions Direct endomyocardial implantation of autologous BM cells significantly improved global LVEF, regional wall thickening and myocardial perfusion reserve, and reduced percentage area of peri-infarct regions in patients with severe CAD.

Religious perspectives on umbilical cord blood banking.

Science.gov (United States)

Jordens, Christopher F C; O'Connor, Michelle A C; Kerridge, Ian H; Stewart, Cameron; Cameron, Andrew; Keown, Damien; Lawrence, Rabbi Jeremy; McGarrity, Andrew; Sachedina, Abdulaziz; Tobin, Bernadette

2012-03-01

Umbilical cord blood is a valuable source of haematopoietic stem cells. There is little information about whether religious affiliations have any bearing on attitudes to and decisions about its collection, donation and storage. The authors provided information about umbilical cord blood banking to expert commentators from six major world religions (Catholicism, Anglicanism, Islam, Judaism, Hinduism and Buddhism) and asked them to address a specific set of questions in a commentary. The commentaries suggest there is considerable support for umbilical cord blood banking in these religions. Four commentaries provide moral grounds for favouring public donation over private storage. None attach any particular religious significance to the umbilical cord or to the blood within it, nor place restrictions on the ethnicity or religion of donors and recipients. Views on ownership of umbilical cord blood vary. The authors offer a series of general points for those who seek a better understanding of religious perspectives on umbilical cord blood banking.

Influence of directionality and maximal power output on speech understanding with bone anchored hearing implants in single sided deafness

OpenAIRE

Krempaska, Silvia; Koval, Juraj; Schmid, Christoph; Pfiffner, Flurin; Kurz, Anja; Kompis, Martin

2014-01-01

Bone-anchored hearing implants (BAHI) are routinely used to alleviate the effects of the acoustic head shadow in single-sided sensorineural deafness (SSD). In this study, the influence of the directional microphone setting and the maximum power output of the BAHI sound processor on speech understanding in noise in a laboratory setting were investigated. Eight adult BAHI users with SSD participated in this pilot study. Speech understanding in noise was measured using a new Slovak speech-in-noi...

Prosthetic management of malpositioned implant using custom cast abutment

Science.gov (United States)

Chatterjee, Aishwarya; Ragher, Mallikarjuna; Patil, Sanket; Chatterjee, Debopriya; Dandekeri, Savita; Prabhu, Vishnu

2015-01-01

Two cases are reported with malpositioned implants. Both the implants were placed 6–7 months back. They had osseointegrated well with the surrounding bone. However, they presented severe facial inclination. Case I was restored with custom cast abutment with an auto polymerizing acrylic gingival veneer. Case II was restored with custom cast UCLA type plastic implant abutment. Ceramic was directly fired on the custom cast abutments. The dual treatment strategy resulted in functional and esthetic restorations despite facial malposition of the implants. PMID:26538957

Clinical Use and Patentability of Cord Blood

Science.gov (United States)

Cavusoglu, Turker; Kilic, Kubilay Dogan; Yigitturk, Gurkan; Tomruk, Canberk; Turgut, Mehmet; Uyanikgil, Yigit

2018-03-14

The blood in the umbilical cord that provides the connection between mother and fetus during pregnancy is called cord blood. The blood of umbilical cord which is usually got rid of following birth, is a very rich stem cell source. Cord blood collection gives no harm to the mother and baby. Besides, its allogeneic and au-tologous usage, the most important disadvantage is that the number of cells is insufficient in adults. Today, it is predominantly used for therapeutic purposes for many diseases. The aim of this review is giving a detailed information about groups of stem cells in cord blood and determining the point of clinical use. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Transverse microanalysis of high energy Ion implants

Energy Technology Data Exchange (ETDEWEB)

Dooley, S.P.; Jamieson, D.N.; Nugent, K.W.; Prawer, S. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

1996-12-31

High energy ion implants in semiconductor materials have been analyzed by Channeling Contrast Microscopy (CCM) perpendicular to the implant direction, allowing imaging of the entire ion track. The damage produced by Channeled and Random 1.4 MeV H{sup +} implants into the edge of a <100> type IIa diamond wafer were analyzed by channeling into the face of the crystal. The results showed negligible damage in the surface region of the implants, and swelling induced misalignment at the end of range of the implants. Channeled 1.4 MeV H{sup +} implants in diamond had a range only 9% deeper than Random implants, which could be accounted for by dechanneling of the beam. The channeling of H{sup +}{sub 2} ions has been previously found to be identical to that of protons of half energy, however the current experiment has shown a 1% increase in {chi}{sub min} for H{sup +}{sub 2} in diamond compared to H{sup +} at 1,2 MeV per proton. This is due to repulsion between protons within the same channel. 5 refs., 2 figs.

Transverse microanalysis of high energy Ion implants

Energy Technology Data Exchange (ETDEWEB)

Dooley, S P; Jamieson, D N; Nugent, K W; Prawer, S [Melbourne Univ., Parkville, VIC (Australia). School of Physics

1997-12-31

High energy ion implants in semiconductor materials have been analyzed by Channeling Contrast Microscopy (CCM) perpendicular to the implant direction, allowing imaging of the entire ion track. The damage produced by Channeled and Random 1.4 MeV H{sup +} implants into the edge of a <100> type IIa diamond wafer were analyzed by channeling into the face of the crystal. The results showed negligible damage in the surface region of the implants, and swelling induced misalignment at the end of range of the implants. Channeled 1.4 MeV H{sup +} implants in diamond had a range only 9% deeper than Random implants, which could be accounted for by dechanneling of the beam. The channeling of H{sup +}{sub 2} ions has been previously found to be identical to that of protons of half energy, however the current experiment has shown a 1% increase in {chi}{sub min} for H{sup +}{sub 2} in diamond compared to H{sup +} at 1,2 MeV per proton. This is due to repulsion between protons within the same channel. 5 refs., 2 figs.

Alterations in the Genital Microbiota in Women With Spinal Cord Injury.

Science.gov (United States)

Pires, Cristhiane V G; Linhares, Iara M; Serzedello, Felipe; Fukazawa, Eiko I; Baracat, Edmund C; Witkin, Steven S

2016-02-01

To evaluate the vaginal and cervical microbiota in women with spinal cord injury compared with mobile women. Fifty-two women with spinal cord injury (study group) and 57 mobile women (control group) were evaluated in a case-control study. All answered a structured questionnaire and were submitted to the following microbiological tests: microscopic examination of vaginal secretions for Trichomonas vaginalis and yeasts, Nugent score by Gram stain, bacterial culture, yeast culture, and endocervical sampling for Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma species. Candida species detected by direct microscopic examination of vaginal fluid was more common in women with spinal cord injuries than in control women: 17.3% (9/52) compared with 3.5% (2/57), respectively (P=.017). However, the frequency of yeast-positive cultures was similar in both groups (21.2% [10/52] compared with 15.8% [14/57]). Women with spinal cord injury were more likely to have positive vaginal cultures for Escherichia coli (15.4% [8/52] compared with 0% [0/57], P=.002) and Corynebacterium species (25.0% [13/52] compared with 8.8% [5/57], P=.037) and less likely for Lactobacillus species (63.5% [33/52] compared with 94.7% [54/57], Pvaginal microbiota away from a Lactobacillus species-dominated flora and a higher concentration of vaginal Candida species than do mobile women.

Study of the radiation effect in breast implants

International Nuclear Information System (INIS)

Moreno T, L. R.; Ramirez R, A.

2013-01-01

This breast cancer is one of the most important death causes in women. Among the more frequently medical treatment for advanced breast cancer is the mastectomy. This situation leads to silicone implants as an esthetic option. There have been cases in patients with implants where cancer was frequently detected, in which a conventional radiotherapy is required. In this work is presented a study of the probable adverse effects caused by the application of high power X-rays (6-10 MV) to the silicone implants and to the surrounding tissues. In the research carried out at the clinic, none Bolus effect was detected in patients with implants. Our results prescribe that in the case of patients with implants and frequent breast cancer, the removal of implants is not necessary due radiotherapy works directly in the damaged tissues. (Author)

Study of the radiation effect in breast implants

Energy Technology Data Exchange (ETDEWEB)

Moreno T, L. R.; Ramirez R, A., E-mail: lumor2000@yahoo.com.mx [Universidad Autonoma Metropolitana, Unidad Azcapotzalco, Departamento de Ciencias Basicas, Av. San Pablo No. 180, Col. Reynosa Tamaulipas, 02200 Mexico D. F. (Mexico)

2013-10-01

This breast cancer is one of the most important death causes in women. Among the more frequently medical treatment for advanced breast cancer is the mastectomy. This situation leads to silicone implants as an esthetic option. There have been cases in patients with implants where cancer was frequently detected, in which a conventional radiotherapy is required. In this work is presented a study of the probable adverse effects caused by the application of high power X-rays (6-10 MV) to the silicone implants and to the surrounding tissues. In the research carried out at the clinic, none Bolus effect was detected in patients with implants. Our results prescribe that in the case of patients with implants and frequent breast cancer, the removal of implants is not necessary due radiotherapy works directly in the damaged tissues. (Author)

Current concepts of regenerative biomaterials in implant dentistry

Directory of Open Access Journals (Sweden)

Annapurna Ahuja

2015-01-01

Full Text Available The primary objective of any implant system is to achieve firm fixation to the bone and this could be influenced by biomechanical as well as biomaterial selection. An array of materials is used in the replacement of missing teeth through implantation. The appropriate selection of biomaterials directly influences the clinical success and longevity of implants. Thus the clinician needs to have adequate knowledge of the various biomaterials and their properties for their judicious selection and application in his/her clinical practice. The recent materials such as bioceramics and composite biomaterials that are under consideration and investigation have a promising future. For optimal performance, implant biomaterials should have suitable mechanical strength, biocompatibility, and structural biostability in the physiological environment. This article reviews the various implant biomaterials and their ease of use in implant dentistry.

Traumatic spinal cord injury in MR imaging

International Nuclear Information System (INIS)

Bronarski, J.; Wozniak, E.

1993-01-01

Spinal cord injuries in tetraplegics were briefly discussed on the basis of MR imaging. It was found that severe cervical spine trauma usually results in concussion - the complete transection of the cord is rare. A case of 19 years old male with total cord transection confirmed by MR imaging is described. (author)

Neurophysiological detection of impending spinal cord injury during scoliosis surgery.

Science.gov (United States)

Schwartz, Daniel M; Auerbach, Joshua D; Dormans, John P; Flynn, John; Drummond, Denis S; Bowe, J Andrew; Laufer, Samuel; Shah, Suken A; Bowen, J Richard; Pizzutillo, Peter D; Jones, Kristofer J; Drummond, Denis S

2007-11-01

Despite the many reports attesting to the efficacy of intraoperative somatosensory evoked potential monitoring in reducing the prevalence of iatrogenic spinal cord injury during corrective scoliosis surgery, these afferent neurophysiological signals can provide only indirect evidence of injury to the motor tracts since they monitor posterior column function. Early reports on the use of transcranial electric motor evoked potentials to monitor the corticospinal motor tracts directly suggested that the method holds great promise for improving detection of emerging spinal cord injury. We sought to compare the efficacy of these two methods of monitoring to detect impending iatrogenic neural injury during scoliosis surgery. We reviewed the intraoperative neurophysiological monitoring records of 1121 consecutive patients (834 female and 287 male) with adolescent idiopathic scoliosis (mean age, 13.9 years) treated between 2000 and 2004 at four pediatric spine centers. The same group of experienced surgical neurophysiologists monitored spinal cord function in all patients with use of a standardized multimodality technique with the patient under total intravenous anesthesia. A relevant neurophysiological change (an alert) was defined as a reduction in amplitude (unilateral or bilateral) of at least 50% for somatosensory evoked potentials and at least 65% for transcranial electric motor evoked potentials compared with baseline. Thirty-eight (3.4%) of the 1121 patients had recordings that met the criteria for a relevant signal change (i.e., an alert). Of those thirty-eight patients, seventeen showed suppression of the amplitude of transcranial electric motor evoked potentials in excess of 65% without any evidence of changes in somatosensory evoked potentials. In nine of the thirty-eight patients, the signal change was related to hypotension and was corrected with augmentation of the blood pressure. The remaining twenty-nine patients had an alert that was related directly to a

Reaction to topical capsaicin in spinal cord injury patients with and without central pain

DEFF Research Database (Denmark)

Finnerup, Nanna Brix; Pedersen, Louise H.; Terkelsen, Astrid J.

2007-01-01

of a spinal cord injury which already is hyperexcitable, would cause enhanced responses in patients with central pain at the level of injury compared to patients without neuropathic pain and healthy controls. Touch, punctuate stimuli, cold stimuli and topical capsaicin was applied above, at, and below injury......Central neuropathic pain is a debilitating and frequent complication to spinal cord injury (SCI). Excitatory input from hyperexcitable cells around the injured grey matter zone is suggested to play a role for central neuropathic pain felt below the level of a spinal cord injury. Direct evidence...... for this hypothesis is difficult to obtain. Capsaicin, activating TRPV1 receptors on small sensory afferents, induces enhanced cellular activity in dorsal horn neurons and produces a central mediated area of secondary hyperalgesia. We hypothesized that sensory stimuli and capsaicin applied at and just above the level...

Functional and metabolic changes in the brain in neuropathic pain syndrome against the background of chronic epidural electrostimulation of the spinal cord.

Science.gov (United States)

Sufianov, A A; Shapkin, A G; Sufianova, G Z; Elishev, V G; Barashin, D A; Berdichevskii, V B; Churkin, S V

2014-08-01

Changes in functional and metabolic activities of the brain were evaluated by EEG and positron-emission/computer tomography with 18F-fluorodeoxyglucose in patients with neuropathic pain syndrome previous to and 3 months after implantation of a system for chronic epidural spinal cord stimulation. In most cases, the use of a nerve stimulator was followed by alleviation of neuropathic pain and partial normalization of functional and metabolic activities of brain structures responsible for pain perception, emotiogenic, behavioral, and autonomic responses.

Short Implants: New Horizon in Implant Dentistry.

Science.gov (United States)

Jain, Neha; Gulati, Manisha; Garg, Meenu; Pathak, Chetan

2016-09-01

The choice of implant length is an essential factor in deciding the survival rates of these implants and the overall success of the prosthesis. Placing an implant in the posterior part of the maxilla and mandible has always been very critical due to poor bone quality and quantity. Long implants can be placed in association with complex surgical procedures such as sinus lift and bone augmentation. These techniques are associated with higher cost, increased treatment time and greater morbidity. Hence, there is need for a less invasive treatment option in areas of poor bone quantity and quality. Data related to survival rates of short implants, their design and prosthetic considerations has been compiled and structured in this manuscript with emphasis on the indications, advantages of short implants and critical biomechanical factors to be taken into consideration when choosing to place them. Studies have shown that comparable success rates can be achieved with short implants as those with long implants by decreasing the lateral forces to the prosthesis, eliminating cantilevers, increasing implant surface area and improving implant to abutment connection. Short implants can be considered as an effective treatment alternative in resorbed ridges. Short implants can be considered as a viable treatment option in atrophic ridge cases in order to avoid complex surgical procedures required to place long implants. With improvement in the implant surface geometry and surface texture, there is an increase in the bone implant contact area which provides a good primary stability during osseo-integration.

Efficacy of spinal cord stimulators in treating peripheral neuropathy: a case series.

Science.gov (United States)

Abd-Elsayed, Alaa; Schiavoni, Nick; Sachdeva, Harsh

2016-02-01

Peripheral neuropathy is a common cause of pain, and it is increasing in prevalence. Peripheral neuropathic pain is very hard to treat and can be resistant to multiple pain management modalities. Our series aimed at testing the efficacy of spinal cord stimulators (SCSs) in treating resistant painful peripheral neuropathy. Case 1: A 79-year-old man presented to our clinic with long-standing history of painful peripheral diabetic neuropathy resistant to conservative management. After failure of all possible modalities, we offered the patient an SCS trial that was very successful, and we proceeded with the permanent implant that continued to help with his pain and allowed the patient to wean down his medications. Case 2: A 60-year-old man presented with chronic peripheral neuropathy secondary to HIV, patient failed all conservative and procedural management. Patient then had an SCS trial that relieved his pain significantly. Unfortunately, we did not proceed with the implant due to deterioration of the patient general health. Case 3: A 39-year-old woman presented with painful peripheral neuropathy secondary to chemotherapy for breast cancer. After failure of medication management and procedures, patient had a SCS trial that improved her pain and we then proceeded with performing the permanent implant that controlled her pain. We presented 3 cases with chronic painful peripheral neuropathy secondary to HIV, diabetes mellitus, and chemotherapy that was resistant to conservative pain management and procedures that was successfully treated with neurostimulation. Copyright © 2016 Elsevier Inc. All rights reserved.

[What kind of health information search the spinal cord injured patients from Spain on the internet?].

Science.gov (United States)

Bea-Muñoz, Manuel; Medina-Sánchez, María; Flórez-García, Mariano

2015-04-16

Internet is an alternative for health education to the population. Spinal cord injured individuals usually consult the Internet about their health problems. To identify the health information sources, the more consulted items and the confidence in Internet information of a group of spinal cord injured individuals from Spain. A survey to spinal cord injured individuals from Spain was conducted, with a questionnaire in Google Drive. It was accessible with a link in ASPAYM-Asturias web page. The questionnaire included epidemiological data and information about Internet use and confidence in its contents. 121 individuals answered the survey, 64% male, with an average age of 45 years. The predominant aetiology was traumatic (70%) and 72% were paraplegics. 83% prefer to consult health care providers directly. More of 70% of the sample searches health problems on the Internet, mostly web pages in Spanish. The preferred item was 'orthopaedic materials and wheelchairs'. 27% of the sample trusts in the Internet information and 32% don't. This research provides information about Internet use of spinal cord injured individuals in Spain. Although we have to admit some bias in the study, more than 70% of the sample searches health problems on the Internet, mostly web pages in Spanish. About one in four individuals trust in information from Internet and most of the sample prefers recommendations directly from healthcare professionals.

Cord lactate, pH, and blood gases from healthy neonates.

Science.gov (United States)

Shirey, T; St Pierre, J; Winkelman, J

1996-01-01

Lactate, pH, pO2, and pCO2 were determined in arterial, venous, and free-flowing mixed umbilical cord blood obtained from deliveries of apparently healthy neonates. The goals of this study were to establish reference ranges for lactate and pH against which results in cases of high-risk labor and delivery could be compared, to see how the gases correlated with these values, and to determine whether easily accessible mixed umbilical cord blood can serve as the sample in lieu of cord arterial or cord venous blood. Arterial and venous cord lactates were 2.98 mmol/l (+/- 1.40) and 2.80 mmol/l (+/- 1.35), respectively, from 85 cords obtained from vaginal and cesarean deliveries. Mixed cord blood lactate, obtained on 48 cords, was 2.72 mmol/l (+/- 1.28) versus 3.14 and 2.97 mmol/l for the arterial and venous samples from those cords, respectively, and correlated quite well with lactate from the venous specimens (r = 0.97). Differences of > 0.5 mmol/l occurred between mixed and arterial cord bloods in 21 patients, and between mixed and venous cord bloods in 6 of the 48 patients, respectively. We conclude that (1) less than 2.5% of deliveries of apparently healthy neonates have arterial, venous, or mixed cord lactates > or = 7.0 mmol/l and pH pO2 nor pCO2 correlate well with cord venous lactate, and (3) readily available mixed cord blood is a satisfactory specimen for the measurement of venous cord latate.

Effect of low dose irradiation on expression of membrane molecules of T lymphocytes in cord blood

International Nuclear Information System (INIS)

Liu Chang'an; Yang Guang; Jia Tingzhen

2001-01-01

The membrane molecules expression of T lymphocytes of cord blood after low dose irradiation (LDI) was investigated. Freshly isolated lymphocytes from cord blood were irradiated with 62 mGy γ-ray. At different time (4 h, 12 h, 24 h) after irradiation the changes of TCR + , CD3 + , CD4 + , CD8 + cells were examined by flow cytometry with direct immunofluorescence, respectively. The experimental results showed that the proportion of CD3 + , TCR + /CD3 + , CD4 + , CD8 + cells increased significantly after LDI, with the most obvious enhancement noted in the 24 h experimental group. The ratio of CD4 to CD8 showed no significant changes. It is suggested that expedition of the maturation, activation and signal transduction of T lymphocytes from cord blood can be induced by irradiation of 62 mGy γ-ray. So the reconstruction of immune functions after cord blood transplantation can be accelerated, enhancing the graft versus leukemia (GVL) effect and preventing the tumor from relapsing

Influence of Palatal Coverage and Implant Distribution on Implant Strain in Maxillary Implant Overdentures.

Science.gov (United States)

Takahashi, Toshihito; Gonda, Tomoya; Mizuno, Yoko; Fujinami, Yozo; Maeda, Yoshinobu

2016-01-01

Maxillary implant overdentures are often used in clinical practice. However, there is no agreement or established guidelines regarding prosthetic design or optimal implant placement configuration. The purpose of this study was to examine the influence of palatal coverage and implant number and distribution in relation to impact strain under maxillary implant overdentures. A maxillary edentulous model with implants and experimental overdentures with and without palatal coverage was fabricated. Four strain gauges were attached to each implant, and they were positioned in the anterior, premolar, and molar areas. A vertical occlusal load of 98 N was applied through a mandibular complete denture, and the implant strains were compared using one-way analysis of variance (P = .05). The palatolabial strain was much higher on anterior implants than on other implants in both denture types. Although there was no significant difference between the strain under dentures with and without palatal coverage, palateless dentures tended to result in higher implant strain than dentures with palatal coverage. Dentures supported by only two implants registered higher strain than those supported by four or six implants. Implants under palateless dentures registered higher strain than those under dentures with palatal coverage. Anterior implants exhibited higher palatolabial strain than other implants regardless of palatal coverage and implant configuration; it is therefore recommended that maxillary implant overdentures should be supported by six implants with support extending to the distal end of the arch.

CORD PROLAPSE, ASSOCIATED FACTORS AND FETAL OUTCOME

African Journals Online (AJOL)

Several factors predispose to cord prolapse, amongst which are breech presentation, abnormal lie and presentation, hydramnios and long cord [2-3, 5-7]. Perinatal mortality is the most feared complication and often seen in up to 91% of cases [8-9]. Little is known about the pattern of umbilical cord prolapse in Cameroon as ...

On-line cone beam CT image guidance for vocal cord tumor targeting

International Nuclear Information System (INIS)

Osman, Sarah O.S.; Boer, Hans C.J. de; Astreinidou, Eleftheria; Gangsaas, Anne; Heijmen, Ben J.M.; Levendag, Peter C.

2009-01-01

Background and purpose: We are developing a technique for highly focused vocal cord irradiation in early glottic carcinoma to optimally treat a target volume confined to a single cord. This technique, in contrast with the conventional methods, aims at sparing the healthy vocal cord. As such a technique requires sub-mm daily targeting accuracy to be effective, we investigate the accuracy achievable with on-line kV-cone beam CT (CBCT) corrections. Materials and methods: CBCT scans were obtained in 10 early glottic cancer patients in each treatment fraction. The grey value registration available in X-ray volume imaging (XVI) software (Elekta, Synergy) was applied to a volume of interest encompassing the thyroid cartilage. After application of the thus derived corrections, residue displacements with respect to the planning CT scan were measured at clearly identifiable relevant landmarks. The intra- and inter-observer variations were also measured. Results: While before correction the systematic displacements of the vocal cords were as large as 2.4 ± 3.3 mm (cranial-caudal population mean ± SD Σ), daily CBCT registration and correction reduced these values to less than 0.2 ± 0.5 mm in all directions. Random positioning errors (SD σ) were reduced to less than 1 mm. Correcting only for translations and not for rotations did not appreciably affect this accuracy. The residue random displacements partly stem from intra-observer variations (SD = 0.2-0.6 mm). Conclusion: The use of CBCT for daily image guidance in combination with standard mask fixation reduced systematic and random set-up errors of the vocal cords to <1 mm prior to the delivery of each fraction dose. Thus, this facilitates the high targeting precision required for a single vocal cord irradiation.

Clinical implementation of stereotaxic brain implant optimization

International Nuclear Information System (INIS)

Rosenow, U.F.; Wojcicka, J.B.

1991-01-01

This optimization method for stereotaxic brain implants is based on seed/strand configurations of the basic type developed for the National Cancer Institute (NCI) atlas of regular brain implants. Irregular target volume shapes are determined from delineation in a stack of contrast enhanced computed tomography scans. The neurosurgeon may then select up to ten directions, or entry points, of surgical approach of which the program finds the optimal one under the criterion of smallest target volume diameter. Target volume cross sections are then reconstructed in 5-mm-spaced planes perpendicular to the implantation direction defined by the entry point and the target volume center. This information is used to define a closed line in an implant cross section along which peripheral seed strands are positioned and which has now an irregular shape. Optimization points are defined opposite peripheral seeds on the target volume surface to which the treatment dose rate is prescribed. Three different optimization algorithms are available: linear least-squares programming, quadratic programming with constraints, and a simplex method. The optimization routine is implemented into a commercial treatment planning system. It generates coordinate and source strength information of the optimized seed configurations for further dose rate distribution calculation with the treatment planning system, and also the coordinate settings for the stereotaxic Brown-Roberts-Wells (BRW) implantation device

Current use of implantable electrical devices in Sweden: data from the Swedish pacemaker and implantable cardioverter-defibrillator registry.

Science.gov (United States)

Gadler, Fredrik; Valzania, Cinzia; Linde, Cecilia

2015-01-01

The National Swedish Pacemaker and Implantable Cardioverter-Defibrillator (ICD) Registry collects prospective data on all pacemaker and ICD implants in Sweden. We aimed to report the 2012 findings of the Registry concerning electrical devices implantation rates and changes over time, 1 year complications, long-term device longevity and patient survival. Forty-four Swedish implanting centres continuously contribute implantation of pacemakers and ICDs to the Registry by direct data entry on a specific website. Clinical and technical information on 2012 first implants and postoperative complications were analysed and compared with previous years. Patient survival data were obtained from the Swedish population register database. In 2012, the mean pacemaker and ICD first implantation rates were 697 and 136 per million inhabitants, respectively. The number of cardiac resynchronization therapy (CRT) first implantations/million capita was 41 (CRT pacemakers) and 55 (CRT defibrillators), with only a slight increase in CRT-ICD rate compared with 2011. Most device implantations were performed in men. Complication rates for pacemaker and ICD procedures were 5.3 and 10.1% at 1 year, respectively. Device and lead longevity differed among manufacturers. Pacemaker patients were older at the time of first implant and had generally worse survival rate than ICD patients (63 vs. 82% after 5 years). Pacemaker and ICD implantation rates seem to have reached a level phase in Sweden. Implantable cardioverter-defibrillator and CRT implantation rates are very low and do not reflect guideline indications. Gender differences in CRT and ICD implantations are pronounced. Device and patient survival rates are variable, and should be considered when deciding device type. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

Implant stability and marginal bone level of microgrooved zirconia dental implants: A 3-month experimental study on dogs

Directory of Open Access Journals (Sweden)

Delgado-Ruíz Rafael Arcesio

2014-01-01

Full Text Available Background/Aim. The modification of implant surfaces could affect mechanical implant stability as well as dynamics and quality of peri-implant bone healing. The aim of this 3-month experimental study in dogs was to investigate implant stability, marginal bone levels and bone tissue response to zirconia dental implants with two laser-micro-grooved intraosseous surfaces in comparison with nongrooved sandblasted zirconia and sandblasted, high-temperature etched titanium implants. Methods. Implant surface characterization was performed using optical interferometric profilometry and energy dispersive X-ray spectroscopy. A total of 96 implants (4 mm in diameter and 10 mm in length were inserted randomly in both sides of the lower jaw of 12 Fox Hound dogs divided into groups of 24 each: the control (titanium, the group A (sandblasted zirconia, the group B (sandblasted zirconia plus microgrooved neck and the group C (sandblasted zirconia plus all microgrooved. All the implants were immediately loaded. Insertion torque, periotest values, radiographic crestal bone level and removal torque were recorded during the 3-month follow-up. Qualitative scanning electon micro-scope (SEM analysis of the bone-implant interfaces of each group was performed. Results. Insertion torque values were higher in the group C and control implants (p the control > the group B > the group A (p the control > the group B > the group A (p < 0.05. SEM showed that implant surfaces of the groups B and C had an extra bone growth inside the microgrooves that corresponded to the shape and direction of the microgrooves. Conclusion. The addition of micro-grooves to the entire intraosseous surface of zirconia dental implants enhances primary and secondary implant stability, promotes bone tissue ingrowth and preserves crestal bone levels.

Intact fetal ovarian cord formation promotes mouse oocyte survival and development

Directory of Open Access Journals (Sweden)

Pera Renee

2010-01-01

Full Text Available Abstract Background Female reproductive potential, or the ability to propagate life, is limited in mammals with the majority of oocytes lost before birth. In mice, surviving perinatal oocytes are enclosed in ovarian follicles for subsequent oocyte development and function in the adult. Before birth, fetal germ cells of both sexes develop in clusters, or germline cysts, in the undifferentiated gonad. Upon sex determination of the fetal gonad, germ cell cysts become organized into testicular or ovarian cord-like structures and begin to interact with gonadal somatic cells. Although germline cysts and testicular cords are required for spermatogenesis, the role of cyst and ovarian cord formation in mammalian oocyte development and female fertility has not been determined. Results Here, we examine whether intact fetal ovarian germ and somatic cell cord structures are required for oocyte development using mouse gonad re-aggregation and transplantation to disrupt gonadal organization. We observed that germ cells from disrupted female gonad prior to embryonic day e13.5 completed prophase I of meiosis but did not survive following transplantation. Furthermore, re-aggregated ovaries from e13.5 to e15.5 developed with a reduced number of oocytes. Oocyte loss occurred before follicle formation and was associated with an absence of ovarian cord structure and ovary disorganization. However, disrupted ovaries from e16.5 or later were resistant to the re-aggregation impairment and supported robust oocyte survival and development in follicles. Conclusions Thus, we demonstrate a critical window of oocyte development from e13.5 to e16.5 in the intact fetal mouse ovary, corresponding to the establishment of ovarian cord structure, which promotes oocyte interaction with neighboring ovarian somatic granulosa cells before birth and imparts oocytes with competence to survive and develop in follicles. Because germline cyst and ovarian cord structures are conserved in the

Why New Spinal Cord Plasticity Does Not Disrupt Old Motor Behaviors.

Science.gov (United States)

Chen, Yi; Chen, Lu; Wang, Yu; Chen, Xiang Yang; Wolpaw, Jonathan R

2017-08-23

When new motor learning changes the spinal cord, old behaviors are not impaired; their key features are preserved by additional compensatory plasticity. To explore the mechanisms responsible for this compensatory plasticity, we transected the spinal dorsal ascending tract before or after female rats acquired a new behavior-operantly conditioned increase or decrease in the right soleus H-reflex-and examined an old behavior-locomotion. Neither spinal dorsal ascending tract transection nor H-reflex conditioning alone impaired locomotion. Nevertheless, when spinal dorsal ascending tract transection and H-reflex conditioning were combined, the rats developed a limp and a tilted posture that correlated in direction and magnitude with the H-reflex change. When the right H-reflex was increased by conditioning, the right step lasted longer than the left and the right hip was higher than the left; when the right H-reflex was decreased by conditioning, the opposite occurred. These results indicate that ascending sensory input guides the compensatory plasticity that normally prevents the plasticity underlying H-reflex change from impairing locomotion. They support the concept of the state of the spinal cord as a negotiated equilibrium that reflects the concurrent influences of all the behaviors in an individual's repertoire; and they support the new therapeutic strategies this concept introduces. SIGNIFICANCE STATEMENT The spinal cord provides a reliable final common pathway for motor behaviors throughout life. Until recently, its reliability was explained by the assumption that it is hardwired; but it is now clear that the spinal cord changes continually as new behaviors are acquired. Nevertheless, old behaviors are preserved. This study shows that their preservation depends on sensory feedback from the spinal cord to the brain: if feedback is removed, the acquisition of a new behavior may disrupt an old behavior. In sum, when a new behavior changes the spinal cord, sensory

Cord blood banking and transplantation: advances and controversies.

Science.gov (United States)

Yoder, Mervin C

2014-04-01

A review of articles published since January 2012 on the topic of cord blood banking and cord blood stem cell transplantation was conducted for this the 25th anniversary year of the first cord blood transplant performed in a human. Cord blood banking is performed throughout the world. Umbilical cord blood (UCB) transplantation is recognized as an acceptable alternative stem cell source for paediatric and adults requiring a haematopoietic transplant, particularly for patients of racial and ethnic minorities. To further advance the use of UCB, methods to enhance UCB stem cell expansion, engraftment and maintenance may be required. Controversy on the most effective and economically sustainable model for banking and storing an optimal UCB product continues to persist. Cord blood banking and transplantation of cord blood stem cells has advanced rapidly over the initial 25 years, as more than 30 ,000 patients have benefited from the therapy. New concepts on the use of methods to expand UCB stem cells for transplantation and use for nonhaematopoietic indications may increase demand for UCB over the next few decades.

Spinal cord injury reveals multilineage differentiation of ependymal cells.

Directory of Open Access Journals (Sweden)

Konstantinos Meletis

2008-07-01

Full Text Available Spinal cord injury often results in permanent functional impairment. Neural stem cells present in the adult spinal cord can be expanded in vitro and improve recovery when transplanted to the injured spinal cord, demonstrating the presence of cells that can promote regeneration but that normally fail to do so efficiently. Using genetic fate mapping, we show that close to all in vitro neural stem cell potential in the adult spinal cord resides within the population of ependymal cells lining the central canal. These cells are recruited by spinal cord injury and produce not only scar-forming glial cells, but also, to a lesser degree, oligodendrocytes. Modulating the fate of ependymal progeny after spinal cord injury may offer an alternative to cell transplantation for cell replacement therapies in spinal cord injury.

Ion implantation control system

International Nuclear Information System (INIS)

Gault, R. B.; Keutzer, L. L.

1985-01-01

A control system is disclosed for an ion implantation system of the type in which the wafers to be implanted are mounted around the periphery of a disk which rotates and also moves in a radial direction relative to an ion beam to expose successive sections of each wafer to the radiation. The control system senses beam current which passes through one or more apertures in the disk and is collected by a Faraday cup. This current is integrated to obtain a measure of charge which is compared with a calculated value based upon the desired ion dosage and other parameters. The resultant controls the number of incremental steps the rotating disk moves radially to expose the adjacent sections of each wafer. This process is continued usually with two or more traverses until the entire surface of each wafer has been implanted with the proper ion dosage

Age or experience? The influence of age at implantation and social and linguistic environment on language development in children with cochlear implants.

Science.gov (United States)

Szagun, Gisela; Stumper, Barbara

2012-12-01

The authors investigated the influence of social environmental variables and age at implantation on language development in children with cochlear implants. Participants were 25 children with cochlear implants and their parents. Age at implantation ranged from 6 months to 42 months ( M (age) = 20.4 months, SD = 22.0 months). Linguistic progress was assessed at 12, 18, 24, and 30 months after implantation. At each data point, language measures were based on parental questionnaire and 45-min spontaneous speech samples. Children's language and parents' child-directed language were analyzed. On all language measures, children displayed considerable vocabulary and grammatical growth over time. Although there was no overall effect of age at implantation, younger and older children had different growth patterns. Children implanted by age 24 months made the most marked progress earlier on, whereas children implanted thereafter did so later on. Higher levels of maternal education were associated with faster linguistic progress; age at implantation was not. Properties of maternal language input, mean length of utterance, and expansions were associated with children's linguistic progress independently of age at implantation. In children implanted within the sensitive period for language learning, children's home language environment contributes more crucially to their linguistic progress than does age at implantation.

Different strategies to improve the use of the umbilical cord and cord blood for hematopoietic and other regenerative cell therapies

NARCIS (Netherlands)

Garde, Mark Paul van der

2016-01-01

The umbilical cord and cord blood contain stem cells that can be used for regenerative cell therapies such as hematopoietic stem cell transplantation. However, the application of cord blood is hindered by the slow engraftment of the cells and delayed immune reconstitution compared to stem cells of

Ventilation onset prior to umbilical cord clamping (physiological-based cord clamping improves systemic and cerebral oxygenation in preterm lambs.

Directory of Open Access Journals (Sweden)

Graeme R Polglase

Full Text Available As measurement of arterial oxygen saturation (SpO2 is common in the delivery room, target SpO2 ranges allow clinicians to titrate oxygen therapy for preterm infants in order to achieve saturation levels similar to those seen in normal term infants in the first minutes of life. However, the influence of the onset of ventilation and the timing of cord clamping on systemic and cerebral oxygenation is not known.We investigated whether the initiation of ventilation, prior to, or after umbilical cord clamping, altered systemic and cerebral oxygenation in preterm lambs.Systemic and cerebral blood-flows, pressures and peripheral SpO2 and regional cerebral tissue oxygenation (SctO2 were measured continuously in apnoeic preterm lambs (126±1 day gestation. Positive pressure ventilation was initiated either 1 prior to umbilical cord clamping, or 2 after umbilical cord clamping. Lambs were monitored intensively prior to intervention, and for 10 minutes following umbilical cord clamping.Clamping the umbilical cord prior to ventilation resulted in a rapid decrease in SpO2 and SctO2, and an increase in arterial pressure, cerebral blood flow and cerebral oxygen extraction. Ventilation restored oxygenation and haemodynamics by 5-6 minutes. No such disturbances in peripheral or cerebral oxygenation and haemodynamics were observed when ventilation was initiated prior to cord clamping.The establishment of ventilation prior to umbilical cord clamping facilitated a smooth transition to systemic and cerebral oxygenation following birth. SpO2 nomograms may need to be re-evaluated to reflect physiological management of preterm infants in the delivery room.

Utility of MR imaging in pediatric spinal cord injury

International Nuclear Information System (INIS)

Felsberg, G.J.; Tien, R.D.; Osumi, A.K.; Cardenas, C.A.

1995-01-01

We evaluated the utility of MR imaging in pediatric patients with acute and subacute spinal cord injuries. MR imaging of 22 pediatric patients with suspected traumatic spinal cord injuries was reviewed. MR findings were correlated with physical examination and compared to available radiographs and CT examinations performed at time of presentation. Twelve patients had abnormalities on MR imaging. Seven had spinal cord contusions; five contusions were hemorrhagic. Five of seven patients with cord contusion had normal radiographs and CT exams. Six patients with normal radiographs and CT examinations had abnormal MR studies revealing cord contusion, ligamentous injury, disc herniation, and epidural hematoma. MR is useful in initial evaluation of pediatric patients with spinal cord injuries and in prognosis of future neurologic function. In the setting of spinal cord symptomatology and negative radiographic studies, MR imaging should be performed. Surgically correctable causes of cord compression demonstrated by MR imaging include disc herniation, epidural hematoma, and retropulsed fracture fragments. The entity of spinal cord injury without radiographic abnormality is a diagnosis of exclusion which should only be made after radiologic investigation with radiographs, high-resolution thin-section CT, and MR imaging. (orig.)

Comparison of external and internal implant-abutment connections for implant supported prostheses. A systematic review and meta-analysis.

Science.gov (United States)

Lemos, Cleidiel Aparecido Araujo; Verri, Fellippo Ramos; Bonfante, Estevam Augusto; Santiago Júnior, Joel Ferreira; Pellizzer, Eduardo Piza

2018-03-01

The systematic review and meta-analysis aimed to answer the PICO question: "Do patients that received external connection implants show similar marginal bone loss, implant survival and complication rates as internal connection implants?". Meta-analyses of marginal bone loss, survival rates of implants and complications rates were performed for the included studies. Study eligibility criteria included (1) randomized controlled trials (RCTs) and/or prospective, (2) studies with at least 10 patients, (3) direct comparison between connection types and (4) publications in English language. The Cochrane risk of bias tool was used to assess the quality and risk of bias in RCTs, while Newcastle-Ottawa scale was used for non-RCTs. A comprehensive search strategy was designed to identify published studies on PubMed/MEDLINE, Scopus, and The Cochrane Library databases up to October 2017. The search identified 661 references. Eleven studies (seven RCTs and four prospective studies) were included, with a total of 530 patients (mean age, 53.93 years), who had received a total of 1089 implants (461 external-connection and 628 internal-connection implants). The internal-connection implants exhibited lower marginal bone loss than external-connection implants (PInternal connections had lower marginal bone loss when compared to external connections. However, the implant-abutment connection had no influence on the implant's survival and complication rates. Based on the GRADE approach the evidence was classified as very low to moderate due to the study design, inconsistency, and publication bias. Thus, future research is highly encouraged. Internal connection implants should be preferred over external connection implants, especially when different risk factors that may contribute to increased marginal bone loss are present. Copyright © 2017 Elsevier Ltd. All rights reserved.

From the Rodent Spinal Cord Injury Model to Human Application: Promises and Challenges.

Science.gov (United States)

Dietz, Volker; Schwab, Martin E

2017-05-01

Repair of the spinal cord and improvement of mobility after injury has been a matter of basic and clinical research for several decades. A number of repair approaches were performed in animals, mainly rodent models of spinal cord injury (SCI). Some of these experimental therapies resulted in significant regeneration of tract fibers, formation of new connections and circuits, and associated improvement of mobility. Some clinical trials aiming at translating these approaches to the human condition of an SCI are currently on-going. The present therapy, however, remains rehabiliation: Mobility of patients with an SCI can be improved to a limited extent by the exploition of neuroplasticity. In this article the present state of the art in the field of SCI research will be discussed. Studies dealing with the promotion of spinal cord repair and those directed to improve mobility by exploition of neuroplasticity will be summarized. The promises and challenges of translational basic research in rodent SCI models will be presented.

Effect of fluence on the lattice site of implanted Er and implantation induced strain in GaN

CERN Document Server

Wahl, U; Decoster, S; Vantomme, A; Correi, J G

2009-01-01

A GaN thin film was implanted with 5 × 1014 cm−2 of 60 keV stable 166Er, followed by the implantation of 2 × 1013 cm−2 radioactive 167Tm (t1/2 = 9.3 d) and an annealing sequence up to 900 °C. The emission channeling (EC) technique was applied to assess the lattice location of Er following the Tm decay from the conversion electrons emitted by 167mEr, which showed that more than 50% of 167mEr occupies substitutional Ga sites. The results are briefly compared to a 167mEr lattice location experiment in a GaN sample not pre-implanted with 166Er. In addition, high-resolution X-ray diffraction (HRXRD) was used to characterize the perpendicular strain in the high-fluence implanted film. The HRXRD experiments showed that the Er implantation resulted in an increase of the c-axis lattice constant of the GaN film around 0.5–0.7%. The presence of significant disorder within the implanted region was corroborated by the fact that the EC patterns for off-normal directions exhibit a pronounced angular broadening of t...

COCHLEAR IMPLANTATION PREVALENCE IN ELDERLY

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A. V. Starokha

2014-01-01

Full Text Available Current paper describes an experience of cochlear implantation in elderly. Cochlear implantation has become a widely accepted intervention in the treatment of individuals with severe-to-profound sensorineural hearing loss. Cochlear implants are now accepted as a standard of care to optimize hearing and subsequent speech development in children and adults with deafness. But cochlear implantation affects not only hearing abilities, speech perception and speech production; it also has an outstanding impact on the social life, activities and self-esteem of each patient. The aim of this study was to evaluate the cochlear implantation efficacy in elderly with severe to profound sensorineural hearing loss. There were 5 patients under our observation. Surgery was performed according to traditional posterior tympanotomy and cochleostomy for cochlear implant electrode insertion for all observed patients. The study was conducted in two stages: before speech processor’s activation and 3 months later. Pure tone free field audiometry was performed to each patient to assess the efficiency of cochlear implantation in dynamics. The aim of the study was also to evaluate quality of life in elderly with severe to profound sensorineural hearing loss after unilateral cochlear implantation. Each patient underwent questioning with 36 Item Short Form Health Survey (SF-36. SF-36 is a set of generic, coherent, and easily administered quality-of-life measures. The SF-36 consists of eight scaled scores, which are the weighted sums of the questions in their section. Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The eight sections are: physical functioning; physical role functioning; emotional role functioning; vitality; emotional well-being; social role functioning; bodily pain; general health perceptions. Our results demonstrate that cochlear implantation in elderly consistently improved quality of life

Spinal Cord Stimulation

DEFF Research Database (Denmark)

Meier, Kaare

2014-01-01

Spinal cord stimulation (SCS) is a surgical treatment for chronic neuropathic pain that is refractory to other treatment. Originally described by Shealy et al. in 1967(1), it is used to treat a range of conditions such as complex regional pain syndrome (CRPS I)(2), angina pectoris(3), radicular...... pain after failed back surgery syndrome (FBSS)(4), pain due to peripheral nerve injury, stump pain(5), peripheral vascular disease(6) and diabetic neuropathy(7,8); whereas phantom pain(9), postherpetic neuralgia(10), chronic visceral pain(11), and pain after partial spinal cord injury(12) remain more...

Comparison of the effect of topical application of human milk and dry cord care on the bacterial colonization of umbilical cord in newborn infants

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Fatemeh Abbaszadeh

2014-04-01

Full Text Available Background: Breast milk contains significant amounts of compounds that act as natural antimicrobial agents. This study was conducted to compare the effect of topical application of human milk and dry cord care on bacterial colonization in the umbilical cord of newborn infants. Methods: This clinical trial study was carried out on 174 infants in Kashan. The newborns were randomized to mother's milk group and dry cord care group from the birth. In group 1, the mother rubbed her own milk on the cord stump every 12 hours from 3 hours after birth to 2 days after the umbilical cord separation. In group 2, the mother was recommended not to use any material on the cord. Then, the cord samples were taken four times; 3hours after birth, at days 3 and 7, and 2 days after the umbilical cord separation. Results: The findings of the culture two days after umbilical cord separation indicated that low percentage of neonates in the breast milk (23.1% and dry cord care (28.8% groups had bacterial colonization. Moreover, no significant difference was found between the two groups in terms of growth of pathogenic organisms and normal flora of the skin (P>0.05. Conclusion: Given the low prevalence of pathogenic microorganisms in the two groups, it seems using breast milk and dry cord care are equally effective methods of taking care of umbilical cord.

Therapeutic Effect of Platelet-Rich Plasma in Rat Spinal Cord Injuries

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Nan-Fu Chen

2018-04-01

Full Text Available Platelet-rich plasma (PRP is prepared by centrifuging fresh blood in an anticoagulant state, and harvesting the platelet-rich portion or condensing platelets. Studies have consistently demonstrated that PRP concentrates are an abundant source of growth factors, such as platelet-derived growth factor (PDGF, transforming growth factor β (TGF-β, insulin-like growth factor 1 (IGF-1, and epithelial growth factor (EGF. The complex mechanisms underlying spinal cord injury (SCI diminish intrinsic repair and neuronal regeneration. Several studies have suggested that growth factor-promoted axonal regeneration can occur for an extended period after injury. More importantly, the delivery of exogenous growth factors contained in PRP, such as EGF, IGF-1, and TGF-β, has neurotrophic effects on central nervous system (CNS injuries and neurodegenerative diseases. However, only a few studies have investigated the effects of PRP on CNS injuries or neurodegenerative diseases. According to our review of relevant literature, no study has investigated the effect of intrathecal (i.t. PRP injection into the injured spinal cord and activation of intrinsic mechanisms. In the present study, we directly injected i.t. PRP into rat spinal cords and examined the effects of PRP on normal and injured spinal cords. In rats with normal spinal cords, PRP induced microglia and astrocyte activation and PDGF-B and ICAM-1 expression. In rats with SCIs, i.t. PRP enhanced the locomotor recovery and spared white matter, promoted angiogenesis and neuronal regeneration, and modulated blood vessel size. Furthermore, a sustained treatment (a bolus of PRP followed by a 1/3 dose of initial PRP concentration exerted more favorable therapeutic effects than a single dose of PRP. Our findings suggest by i.t. PRP stimulate angiogenesis, enhancing neuronal regeneration after SCI in rats. Although PRP induces minor inflammation in normal and injured spinal cords, it has many advantages. It is an

Investigation of MeV-Cu implantation and channeling effects into porous silicon formation

International Nuclear Information System (INIS)

Ahmad, M.; Naddaf, M.

2011-01-01

P-type (1 1 1) silicon wafers were implanted by copper ions (2.5 MeV) in channeling and random directions using ion beam accelerator of the Atomic Energy Commission of Syria (AECS). The effect of implantation direction on formation process of porous silicon (PS) using electrochemical etching method has been investigated using scanning electron microscope (SEM) and photoluminescence (PL) techniques. SEM observations revealed that the size, shape and density of the formed pores are highly affected by the direction of beam implantation. This in turn is seen to influence the PL behavior of the PS.

Investigation of MeV-Cu implantation and channeling effects into porous silicon formation

International Nuclear Information System (INIS)

Ahmad, M.; Naddaf, M.

2012-01-01

P-type (1 1 1) silicon wafers were implanted by copper ions (2.5 MeV) in channeling and random directions using ion beam accelerator of the Atomic Energy Commission of Syria (AECS). The effect of implantation direction on formation process of porous silicon (PS) using electrochemical etching method has been investigated using scanning electron microscope (SEM) and photoluminescence (PL) techniques. SEM observations revealed that the size, shape and density of the formed pores are highly affected by the direction of beam implantation. This in turn is seen to influence the PL behavior of the PS.(author)

Investigation of MeV-Cu implantation and channeling effects into porous silicon formation

Science.gov (United States)

Ahmad, M.; Naddaf, M.

2011-11-01

P-type (1 1 1) silicon wafers were implanted by copper ions (2.5 MeV) in channeling and random directions using ion beam accelerator of the Atomic Energy Commission of Syria (AECS). The effect of implantation direction on formation process of porous silicon (PS) using electrochemical etching method has been investigated using scanning electron microscope (SEM) and photoluminescence (PL) techniques. SEM observations revealed that the size, shape and density of the formed pores are highly affected by the direction of beam implantation. This in turn is seen to influence the PL behavior of the PS.

Patient specific root-analogue dental implants – additive manufacturing and finite element analysis

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Gattinger Johannes

2016-09-01

Full Text Available Aim of this study was to prove the possibility of manufacturing patient specific root analogue two-part (implant and abutment implants by direct metal laser sintering. The two-part implant design enables covered healing of the implant. Therefore, CT-scans of three patients are used for reverse engineering of the implants, abutments and crowns. Patient specific implants are manufactured and measured concerning dimensional accuracy and surface roughness. Impacts of occlusal forces are simulated via FEA and compared to those of standard implants.

Development of Mandarin spoken language after pediatric cochlear implantation.

Science.gov (United States)

Li, Bei; Soli, Sigfrid D; Zheng, Yun; Li, Gang; Meng, Zhaoli

2014-07-01

The purpose of this study was to evaluate early spoken language development in young Mandarin-speaking children during the first 24 months after cochlear implantation, as measured by receptive and expressive vocabulary growth rates. Growth rates were compared with those of normally hearing children and with growth rates for English-speaking children with cochlear implants. Receptive and expressive vocabularies were measured with the simplified short form (SSF) version of the Mandarin Communicative Development Inventory (MCDI) in a sample of 112 pediatric implant recipients at baseline, 3, 6, 12, and 24 months after implantation. Implant ages ranged from 1 to 5 years. Scores were expressed in terms of normal equivalent ages, allowing normalized vocabulary growth rates to be determined. Scores for English-speaking children were re-expressed in these terms, allowing direct comparisons of Mandarin and English early spoken language development. Vocabulary growth rates during the first 12 months after implantation were similar to those for normally hearing children less than 16 months of age. Comparisons with growth rates for normally hearing children 16-30 months of age showed that the youngest implant age group (1-2 years) had an average growth rate of 0.68 that of normally hearing children; while the middle implant age group (2-3 years) had an average growth rate of 0.65; and the oldest implant age group (>3 years) had an average growth rate of 0.56, significantly less than the other two rates. Growth rates for English-speaking children with cochlear implants were 0.68 in the youngest group, 0.54 in the middle group, and 0.57 in the oldest group. Growth rates in the middle implant age groups for the two languages differed significantly. The SSF version of the MCDI is suitable for assessment of Mandarin language development during the first 24 months after cochlear implantation. Effects of implant age and duration of implantation can be compared directly across

Effects of implant system, impression technique, and impression material on accuracy of the working cast.

Science.gov (United States)

Wegner, Kerstin; Weskott, Katharina; Zenginel, Martha; Rehmann, Peter; Wöstmann, Bernd

2013-01-01

This in vitro study aimed to identify the effects of the implant system, impression technique, and impression material on the transfer accuracy of implant impressions. The null hypothesis tested was that, in vitro and within the parameters of the experiment, the spatial relationship of a working cast to the placement of implants is not related to (1) the implant system, (2) the impression technique, or (3) the impression material. A steel maxilla was used as a reference model. Six implants of two different implant systems (Standard Plus, Straumann; Semados, Bego) were fixed in the reference model. The target variables were: three-dimensional (3D) shift in all directions, implant axis direction, and rotation. The target variables were assessed using a 3D coordinate measuring machine, and the respective deviations of the plaster models from the nominal values of the reference model were calculated. Two different impression techniques (reposition/pickup) and four impression materials (Aquasil Ultra, Flexitime, Impregum Penta, P2 Magnum 360) were investigated. In all, 80 implant impressions for each implant system were taken. Statistical analysis was performed using multivariate analysis of variance. The implant system significantly influenced the transfer accuracy for most spatial dimensions, including the overall 3D shift and implant axis direction. There was no significant difference between the two implant systems with regard to rotation. Multivariate analysis of variance showed a significant effect on transfer accuracy only for the implant system. Within the limits of the present study, it can be concluded that the transfer accuracy of the intraoral implant position on the working cast is far more dependent on the implant system than on the selection of a specific impression technique or material.

DRG Spinal Cord Stimulation as Solution for Patients With Severe Pain Due to Anterior Cutaneous Nerve Entrapment Syndrome: A Case Series.

Science.gov (United States)

Mol, Frédérique Mathilde Ulrike; Roumen, Rudi M H

2018-04-01

Anterior Cutaneous Nerve Entrapment Syndrome (ACNES) is a debilitating neuropathic pain condition. A small portion of patients do not respond to any currently available treatment modalities. These patients, often young women, might benefit from targeted spinal cord stimulation of the dorsal root ganglion (DRG). This retrospective case series describes five ACNES patients who were referred from a Dutch dedicated tertiary referral center to collaborating sites with extensive experience in DRG stimulation to be implanted with a DRG Axium System (St. Jude/Abbott, IL, USA) in the period of 2013-2016. Numeric pain rating scores at routine 6- and 12-month follow-up visits were analyzed. Three patients experienced >50% pain reduction at 12 months follow-up. Four patients experienced device-related complications, such as lead dislocation, lead breakage, pain at the battery site, and overstimulation. This case series suggests DRG spinal cord stimulation can be safe and effective for some patients with persistent pain due to ACNES. © 2017 International Neuromodulation Society.

Dose measurement of ion implanted silicon by RBS technique

International Nuclear Information System (INIS)

Kamawanna, Teerasak; Intarasiri, Saweat; Prapunsri, Chowunchun; Thongleurm, Chome; Maleepatra, Saenee; Singkarat, Somsorn

2003-10-01

Surface modification can be achieved by ion implantation. This study used a 1 mm thick silicon wafer as a target which was implanted with Ar+ at 80 keV. The degree of the modification depends on both the ion energy and the implanted dose. The distribution of argon in the silicon substrate and the absolute implanted dose can be measured by using Rutherford Backscattering Spectrometry (RBS). These investigations utilized a 1.7 MV Tandetron accelerator system at Chiang Mai University. The dose determination by a direct calculation is in agreement with the simulation by the SIMNRA code

Spinal cord magnetic resonance imaging in suspected multiple sclerosis

International Nuclear Information System (INIS)

Lycklama a Nijeholt, G.J.; Bergers, E.; Castelijns, J.A.; Barkhof, F.; Uitdehaag, B.M.J.; Polman, C.H.

2000-01-01

We examined the value of spinal cord magnetic resonance imaging (MRI) in the diagnostic work-up of multiple sclerosis (MS). Forty patients suspected of having MS were examined within 24 months after the start of symptoms. Disability was assessed, and symptoms were categorized as either brain or spinal cord. Work-up further included cerebrospinal fluid analysis and standard proton-density, T2-, and T1-weighted gadolinium-enhanced brain and spinal cord MRI. Patients were categorized as either clinically definite MS (n = 13), laboratory-supported definite MS (n = 14), or clinically probable MS (n = 4); four patients had clinically probable MS, and in nine MS was suspected. Spinal cord abnormalities were found in 35 of 40 patients (87.5 %), consisting of focal lesions in 31, only diffuse abnormalities in two, and both in two. Asymptomatic spinal cord lesions occurred in six patients. All patients with diffuse spinal cord abnormality had clear spinal cord symptoms and a primary progressive disease course. In clinically definite MS, the inclusion of spinal imaging increased the sensitivity of MRI to 100 %. Seven patients without a definite diagnosis had clinically isolated syndromes involving the spinal cord. Brain MRI was inconclusive, while all had focal spinal cord lesions which explained symptoms and ruled out other causes. Two other patients had atypical brain abnormalities suggesting ischemic/vascular disease. No spinal cord abnormalities were found, and during follow-up MS was ruled out. Spinal cord abnormalities are common in suspected MS, and may occur asymptomatic. Although diagnostic classification is seldom changed, spinal cord imaging increases diagnostic sensitivity of MRI in patients with suspected MS. In addition, patients with primary progressive MS may possibly be earlier diagnosed. Finally, differentiation with atypical lesions may be improved. (orig.)

Magnetic resonance imaging of experimental spinal cord injury

International Nuclear Information System (INIS)

Nakamura, Tsutomu; Kumano, Kouichi; Kadoya, Satoru

1989-01-01

Correlation between pathological findings and magnetic resonance imaging (MRI) of experimental cord injury were investigated. Cord injuries were made on ten Wistar rats weighing 80-170 gm by epidural compression of the thoracic cord with a Biemer cerebral vascular clip for 5-20 seconds. Several hours after the procedure animals were examined by spin echo axial MR images with a pulse sequence of TR/TE=1000/36 msec. MR studies were repeated on 4 animals 3-7 days after the initial examination. Immediately after the latest MRI examination animals were sacrificed and fixed with 10% formalin. Three micron thickness paraffin sections stained with hematoxylin and eosin were evaluated under a microscope. The pathological finding was hemorrhagic necrosis with edema of various severity depending on duration of clip application. The hemorrhagic necrosis was observed either unilaterally or bilaterally to the cord. MR findings of the cord were of high intensity in five animals which were severely injured, while central low intensity of the injured cord appeared in three mildly injured animals. Of the remaining two animals which had mild injury, one showed unilateral high intensity, while no definitive change was demonstrated in the other. The high intensity in the MRI suggested edema associated with hemorrhagic necrosis rather than hemorrhage. The central low intensity appearing in the mildly injured cord might be hemorrhage in the gray matter. It is concluded that MRI was useful to diagnose not only the level and severity but also the pathological process in the injured cord, and thus to estimate the prognosis of the cord injuries. (author)

Beam Profile Disturbances from Implantable Pacemakers or Implantable Cardioverter-Defibrillator Interactions

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Gossman, Michael S., E-mail: mgossman@tsrcc.com [Tri-State Regional Cancer Center, Medical Physics Section, Ashland, KY (United States); Comprehensive Heart and Vascular Associates, Heart and Vascular Center, Ashland, KY (United States); Medtronic, Inc., External Research Program, Mounds View, MN (United States); Nagra, Bipinpreet; Graves-Calhoun, Alison; Wilkinson, Jeffrey [Tri-State Regional Cancer Center, Medical Physics Section, Ashland, KY (United States); Comprehensive Heart and Vascular Associates, Heart and Vascular Center, Ashland, KY (United States); Medtronic, Inc., External Research Program, Mounds View, MN (United States)

2011-01-01

The medical community is advocating for progressive improvement in the design of implantable cardioverter-defibrillators and implantable pacemakers to accommodate elevations in dose limitation criteria. With advancement already made for magnetic resonance imaging compatibility in some, a greater need is present to inform the radiation oncologist and medical physicist regarding treatment planning beam profile changes when such devices are in the field of a therapeutic radiation beam. Treatment plan modeling was conducted to simulate effects induced by Medtronic, Inc.-manufactured devices on therapeutic radiation beams. As a continuation of grant-supported research, we show that radial and transverse open beam profiles of a medical accelerator were altered when compared with profiles resulting when implantable pacemakers and cardioverter-defibrillators are placed directly in the beam. Results are markedly different between the 2 devices in the axial plane and the sagittal planes. Vast differences are also presented for the therapeutic beams at 6-MV and 18-MV x-ray energies. Maximum changes in percentage depth dose are observed for the implantable cardioverter-defibrillator as 9.3% at 6 MV and 10.1% at 18 MV, with worst distance to agreement of isodose lines at 2.3 cm and 1.3 cm, respectively. For the implantable pacemaker, the maximum changes in percentage depth dose were observed as 10.7% at 6 MV and 6.9% at 18 MV, with worst distance to agreement of isodose lines at 2.5 cm and 1.9 cm, respectively. No differences were discernible for the defibrillation leads and the pacing lead.

Transcutaneous Spinal Direct Current Stimulation (tsDCS

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Filippo eCogiamanian

2012-07-01

Full Text Available In the past ten years renewed interest has centered on non-invasive transcutaneous weak direct currents applied over the scalp to modulate cortical excitability (brain polarization or transcranial direct current stimulation, tDCS. Extensive literature shows that tDCS induces marked changes in cortical excitability that outlast stimulation.Aiming at developing a new, non invasive, approach to spinal cord neuromodulation we assessed the after-effects of thoracic transcutaneous spinal DC stimulation (tsDCS on somatosensory potentials (SEPs evoked in healthy subjects by posterior tibial nerve (PTN stimulation. Our findings showed that thoracic anodal tsDCS depresses the cervico-medullary PTN-SEP component (P30 without eliciting adverse effects. tsDCS also modulates post-activation H-reflex dynamics. Later works further confirmed that transcutaneous electric fields modulate spinal cord function. Subsequent studies in our laboratory showed that tsDCS modulates the flexion reflex in the human lower limb. Besides influencing the laser evoked potentials, tsDCS increases pain tolerance in healthy subjects. Hence, though the underlying mechanisms remain speculative, tsDCS modulates activity in lemniscal, spinothalamic and segmental motor systems.Here we review currently available experimental evidence that non-invasive spinal cord stimulation influences spinal function in humans and argue that, by focally modulating spinal excitability, tsDCS could provide a novel therapeutic tool complementary to drugs and invasive spinal cord stimulation in managing various pathologic conditions, including pain.

Simulation of peri-implant bone healing due to immediate loading in dental implant treatments.

Science.gov (United States)

Chou, Hsuan-Yu; Müftü, Sinan

2013-03-15

The goal of this work was to investigate the role of immediate loading on the peri-implant bone healing in dental implant treatments. A mechano-regulatory tissue differentiation model that takes into account the stimuli through the solid and the fluid components of the healing tissue, and the diffusion of pluripotent stem cells into the healing callus was used. A two-dimensional axisymmetric model consisting of a dental implant, the healing callus tissue and the host bone tissue was constructed for the finite element analysis. Poroelastic material properties were assigned to the healing callus and the bone tissue. The effects of micro-motion, healing callus size, and implant thread design on the length of the bone-to-implant contact (BIC) and the bone volume (BV) formed in the healing callus were investigated. In general, the analysis predicted formation of a continuous layer of soft tissue along the faces of the implant which are parallel to the loading direction. This was predicted to be correlated with the high levels of distortional strain transferred through the solid component of the stimulus. It was also predicted that the external threads on the implant, redistribute the interfacial load, thus help reduce the high distortional stimulus and also help the cells to differentiate to bone tissue. In addition, the region underneath the implant apex was predicted to experience high fluid stimulus that results in the development of soft tissue. The relationship between the variables considered in this study and the outcome measures, BV and BIC, was found to be highly nonlinear. A three-way analysis of variance (ANOVA) of the results was conducted and it showed that micro-motion presents the largest hindrance to bone formation during healing. Copyright © 2013 Elsevier Ltd. All rights reserved.

Polymer tribology by combining ion implantation and radionuclide tracing

International Nuclear Information System (INIS)

Timmers, Heiko; Gladkis, Laura G.; Warner, Jacob A.; Byrne, Aidan P.; Grosso, Mariela F. del; Arbeitman, Claudia R.; Garcia-Bermudez, Gerardo; Geruschke, Thomas; Vianden, Reiner

2010-01-01

Radionuclide tracers were ion implanted with three different techniques into the ultra-high molecular weight polyethylene polymer. Tracer nuclei of 7 Be were produced with inverse kinematics via the reaction p( 7 Li, 7 Be)n and caught by polymer samples at a forward scattering angle with a maximum implantation energy of 16 MeV. For the first time, 97 Ru, 100 Pd, and, independently, 111 In have been used as radionuclide tracers in ultra-high molecular weight polyethylene. 97 Ru and 100 Pd were recoil-implanted following the fusion evaporation reactions 92 Zr( 12 C,α3n) 97 Ru and 92 Zr( 12 C,4n) 100 Pd with a maximum implantation energy of 8 MeV. 111 In ions were produced in an ion source, mass-separated and implanted at 160 keV. The tribology of implanted polymer samples was studied by tracing the radionuclide during mechanical wear. Uni-directional and bi-directional sliding apparatus with stainless steel actuators were used. Results suggest a debris exchange process as the characteristic feature of the wear-in phase. This process can establish the steady state required for a subsequently constant wear rate in agreement with Archard's equation. The nano-scale implantation of mass-separated 111 In appears best suited to the study of non-linear tribological processes during wear-in. Such non-linear processes may be expected to be important in micro- and nanomachines.

Vocal cord dysfunction related to water-damaged buildings.

Science.gov (United States)

Cummings, Kristin J; Fink, Jordan N; Vasudev, Monica; Piacitelli, Chris; Kreiss, Kathleen

2013-01-01

Vocal cord dysfunction (VCD) is the intermittent paradoxical adduction of the vocal cords during respiration, resulting in variable upper airway obstruction. Exposure to damp indoor environments is associated with adverse respiratory health outcomes, including asthma, but its role in the development of VCD is not well described. We describe the spectrum of respiratory illness in occupants of 2 water-damaged office buildings. The National Institute for Occupational Safety and Health conducted a health hazard evaluation that included interviews with managers, a maintenance officer, a remediation specialist who had evaluated the 2 buildings, employees, and consulting physicians. In addition, medical records and reports of building evaluations were reviewed. Diagnostic evaluations for VCD had been conducted at the Asthma and Allergy Center of the Medical College of Wisconsin. Two cases of VCD were temporally related to occupancy of water-damaged buildings. The patients experienced cough, chest tightness, dyspnea, wheezing, and hoarseness when in the buildings. Spirometry was normal. Methacholine challenge did not show bronchial hyperreactivity but did elicit symptoms of VCD and inspiratory flow-volume loop truncation. Direct laryngoscopy revealed vocal cord adduction during inspiration. Coworkers developed upper and lower respiratory symptoms; their diagnoses included sinusitis and asthma, consistent with recognized effects of exposure to indoor dampness. Building evaluations provided evidence of water damage and mold growth. VCD can occur with exposure to water-damaged buildings and should be considered in exposed patients with asthma-like symptoms. Published by Elsevier Inc.

Validation of the walking index for spinal cord injury in a US and European clinical population

DEFF Research Database (Denmark)

Ditunno, J.F.; Scivoletto, G.; Patrick, M.

2008-01-01

OBJECTIVE: To demonstrate the prospective construct validity of the walking index for spinal cord injury (WISCI) in US/European clinical population. DESIGN: Prospective Cohort in Denmark, Germany, Italy and the USA. PARTICIPANTS/METHOD: Participants with acute complete/incomplete (ASIA Impairment...... Scale (AIS) A, B, C and D) traumatic spinal cord injuries were enrolled from four centers. Lower extremity motor scores (LEMS), WISCI level and Locomotor Functional Independence Measure (LFIM) levels were assessed with change in ambulatory status. WISCI progression was assessed for monotonic direction...

Impact of Different Surgeons on Dental Implant Failure.

Science.gov (United States)

Chrcanovic, Bruno Ramos; Kisch, Jenö; Albrektsson, Tomas; Wennerberg, Ann

To assess the influence of several factors on the prevalence of dental implant failure, with special consideration of the placement of implants by different dental surgeons. This retrospective study is based on 2,670 patients who received 10,096 implants at one specialist clinic. Only the data of patients and implants treated by surgeons who had inserted a minimum of 200 implants at the clinic were included. Kaplan-Meier curves were stratified with respect to the individual surgeon. A generalized estimating equation (GEE) method was used to account for the fact that repeated observations (several implants) were placed in a single patient. The factors bone quantity, bone quality, implant location, implant surface, and implant system were analyzed with descriptive statistics separately for each individual surgeon. A total of 10 surgeons were eligible. The differences between the survival curves of each individual were statistically significant. The multivariate GEE model showed the following variables to be statistically significant: surgeon, bruxism, intake of antidepressants, location, implant length, and implant system. The surgeon with the highest absolute number of failures was also the one who inserted the most implants in sites of poor bone and used turned implants in most cases, whereas the surgeon with the lowest absolute number of failures used mainly modern implants. Separate survival analyses of turned and modern implants stratified for the individual surgeon showed statistically significant differences in cumulative survival. Different levels of failure incidence could be observed between the surgeons, occasionally reaching significant levels. Although a direct causal relationship could not be ascertained, the results of the present study suggest that the surgeons' technique, skills, and/or judgment may negatively influence implant survival rates.

Spinal cord motion. Influence of respiration and cardiac cycle

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Winklhofer, S. [RWTH Aachen University Hospital (Germany). Dept. of Neuroradiology; University Hospital Zurich (Switzerland). Inst. of Diagnostic and Interventional Radiology; Schoth, F. [RWTH Aachen University Hospital (Germany). Dept. of Diagnostic Radiology; Stolzmann, P. [University Hospital Zurich (Switzerland). Inst. of Diagnostic and Interventional Radiology; Krings, T. [Toronto Western Hospital, ON (Canada). Div. of Neuroradiology; Mull, M.; Wiesmann, M. [RWTH Aachen University Hospital (Germany). Dept. of Neuroradiology; Stracke, C.P. [RWTH Aachen University Hospital (Germany). Dept. of Neuroradiology; Alfried-Krupp-Hospital, Essen (Germany). Dept. of Neuroradiology

2014-11-15

To assess physiological spinal cord motion during the cardiac cycle compared with the influence of respiration based on magnetic resonance imaging (MRI) measurements. Anterior-posterior spinal cord motion within the spinal canal was assessed in 16 healthy volunteers (median age, 25 years) by cardiac-triggered and cardiac-gated gradient echo pulse sequence MRI. Image acquisition was performed during breath-holding, normal breathing, and forced breathing. Normal spinal cord motion values were computed using descriptive statistics. Breathing-dependent differences were assessed using the Wilcoxon signed-rank test and compared with the cardiac-based cord motion. A normal value table was set up for the spinal cord motion of each vertebral cervico-thoracic-lumbar segment. Significant differences in cord motion were found between cardiac-based motion while breath-holding and the two breathing modalities (P < 0.01 each). Spinal cord motion was found to be highest during forced breathing, with a maximum in the lower cervical spinal segments (C5; mean, 2.1 mm ± 1.17). Image acquisition during breath-holding revealed the lowest motion. MRI permits the demonstration and evaluation of cardiac and respiration-dependent spinal cord motion within the spinal canal from the cervical to lumbar segments. Breathing conditions have a considerably greater impact than cardiac activity on spinal cord motion.

Spinal cord motion. Influence of respiration and cardiac cycle

International Nuclear Information System (INIS)

Winklhofer, S.; University Hospital Zurich; Schoth, F.; Stolzmann, P.; Krings, T.; Mull, M.; Wiesmann, M.; Stracke, C.P.; Alfried-Krupp-Hospital, Essen

2014-01-01

To assess physiological spinal cord motion during the cardiac cycle compared with the influence of respiration based on magnetic resonance imaging (MRI) measurements. Anterior-posterior spinal cord motion within the spinal canal was assessed in 16 healthy volunteers (median age, 25 years) by cardiac-triggered and cardiac-gated gradient echo pulse sequence MRI. Image acquisition was performed during breath-holding, normal breathing, and forced breathing. Normal spinal cord motion values were computed using descriptive statistics. Breathing-dependent differences were assessed using the Wilcoxon signed-rank test and compared with the cardiac-based cord motion. A normal value table was set up for the spinal cord motion of each vertebral cervico-thoracic-lumbar segment. Significant differences in cord motion were found between cardiac-based motion while breath-holding and the two breathing modalities (P < 0.01 each). Spinal cord motion was found to be highest during forced breathing, with a maximum in the lower cervical spinal segments (C5; mean, 2.1 mm ± 1.17). Image acquisition during breath-holding revealed the lowest motion. MRI permits the demonstration and evaluation of cardiac and respiration-dependent spinal cord motion within the spinal canal from the cervical to lumbar segments. Breathing conditions have a considerably greater impact than cardiac activity on spinal cord motion.

Age-related changes of the spinal cord: A biomechanical study.

Science.gov (United States)

Okazaki, Tomoya; Kanchiku, Tsukasa; Nishida, Norihiro; Ichihara, Kazuhiko; Sakuramoto, Itsuo; Ohgi, Junji; Funaba, Masahiro; Imajo, Yasuaki; Suzuki, Hidenori; Chen, Xian; Taguchi, Toshihiko

2018-03-01

Although it is known that aging plays an important role in the incidence and progression of cervical spondylotic myelopathy (CSM), the underlying mechanism is unclear. Studies that used fresh bovine cervical spinal cord report the gray matter of the cervical spinal cord as being more rigid and fragile than the white matter. However, there are no reports regarding the association between aging an tensile and Finite Element Method (FEM). Therefore, FEM was used based on the data pertaining to the mechanical features of older bovine cervical spinal cord to explain the pathogenesis of CSM in elderly patients. Tensile tests were conducted for white and gray matter separately in young and old bovine cervical spinal cords, and compared with their respective mechanical features. Based on the data obtained, FEM analysis was further performed, which included static and dynamic factors to describe the internal stress distribution changes of the spinal cord. These results demonstrated that the mechanical strength of young bovine spinal cords is different from that of old bovine spinal cords. The gray matter of the older spinal cord was significantly softer and more resistant to rupture compared with that of younger spinal cords (Pspinal cords in response to similar compression, when compared with young spinal cords. These results demonstrate that in analyzing the response of the spinal cord to compression, the age of patients is an important factor to be considered, in addition to the degree of compression, compression speed and parts of the spinal cord compression factor.

Spinal cord regeneration: moving tentatively towards new perspectives.

Science.gov (United States)

Jones, D G; Anderson, E R; Galvin, K A

2003-01-01

The failure of the adult human spinal cord to regenerate following injury is not absolute, but appears to be amenable to therapeutic manipulation. Recent work has shown that the provision of a growth permissive environment by the neutralization of inhibitory influences, or the grafting of fetal tissue, peripheral nerve, Schwann cells, or olfactory ensheathing cells can enhance regeneration in animal models of spinal cord injury. Stem cells are gaining ever-increasing favour as a treatment option for spinal cord injury. The potential of neural stem cells, embryonic stem cells, and bone marrow stromal cells is discussed. Additional treatment options such as pharmacological interventions, functional electrical stimulation and physiotherapy approaches are also explored. Basic science insights are used as a foundation for a discussion of a variety of clinical perspectives including repair of the chronically injured spinal cord, animal models of human spinal cord injuries and clinical trials. A more holistic approach towards spinal cord injury is suggested, one where a hierarchy of needs is recognised and quality of life is paramount. Finally, this review cautions against overly grandiose claims of an imminent miracle cure for human spinal cord injury.

Diffusion tensor imaging of spinal cord parenchyma lesion in rat with chronic spinal cord injury.

Science.gov (United States)

Zhao, Can; Rao, Jia-Sheng; Pei, Xiao-Jiao; Lei, Jian-Feng; Wang, Zhan-Jing; Zhao, Wen; Wei, Rui-Han; Yang, Zhao-Yang; Li, Xiao-Guang

2018-04-01

Adequate evaluation of spinal cord parenchyma and accurate identification of injury range are considered two premises for the research and treatment of chronic spinal cord injury (SCI). Diffusion tensor imaging (DTI) provides information about water diffusion in spinal cord, and thus makes it possible to realize these premises. In this study, we conducted magnetic resonance imaging (MRI) for Wistar rats 84days after spinal cord contusion. DTI metrics including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) from different positions of the injured cord were collected, analyzed, and compared with the histological results and locomotor outcomes. Moreover, we performed fiber tractography, and examined the difference in cavity percentage obtained respectively via conventional MRI, DTI and histology. Results showed that the chronic SCI rats had the largest changes of all DTI metrics at the epicenter; the farther away from the epicenter, the smaller the variation. FA, AD and RD were all influenced by SCI in a greater space range than MD. The good consistency of FA values and histological results in specific regions evidenced FA's capability of reflecting Wallerian degeneration after SCI. DTI metrics at the epicenter in ventral funiculus also showed a close correlation with the BBB scores. Additionally, supported by the histological results, DTI enables a more accurate measurement of cavity percentage compared to the conventional MRI. DTI parameters might comprehensively reflect the post-SCI pathological status of spinal cord parenchyma at the epicenter and distal parts during the chronic stage, while showing good consistency with locomotor performance. DTI combined with tractography could intuitively display the distribution of spared fibers after SCI and accurately provide information such as cavity area. This may shed light on the research and treatment of chronic SCI. Copyright © 2017 Elsevier Inc. All rights

Restoring tactile awareness through the rubber hand illusion in cervical spinal cord injury.

Science.gov (United States)

Lenggenhager, Bigna; Scivoletto, Giorgio; Molinari, Marco; Pazzaglia, Mariella

2013-10-01

Bodily sensations are an important component of corporeal awareness. Spinal cord injury can leave affected body parts insentient and unmoving, leading to specific disturbances in the mental representation of one's own body and the sense of self. Here, we explored how illusions induced by multisensory stimulation influence immediate sensory signals and tactile awareness in patients with spinal cord injuries. The rubber hand illusion paradigm was applied to 2 patients with chronic and complete spinal cord injury of the sixth cervical spine, with severe somatosensory impairments in 2 of 5 fingers. Both patients experienced a strong illusion of ownership of the rubber hand during synchronous, but not asynchronous, stroking. They also, spontaneously reported basic tactile sensations in their previously numb fingers. Tactile awareness from seeing the rubber hand was enhanced by progressively increasing the stimulation duration. Multisensory illusions directly and specifically modulate the reemergence of sensory memories and enhance tactile sensation, despite (or as a result of) prior deafferentation. When sensory inputs are lost, and are later illusorily regained, the brain updates a coherent body image even several years after the body has become permanently unable to feel. This particular example of neural plasticity represents a significant opportunity to strengthen the sense of the self and the feelings of embodiment in patients with spinal cord injury.

A cost analysis of conservative management of spinal cord-injured patients in Nigeria.

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Kawu, A A; Olawepo, A; Salami, A O O; Kuranga, S A; Abdulhameed, S; Esenwah, V C

2011-11-01

A prospective study. To determine the cost of acute phase of injury (ASCI) among spinal cord-injured patients managed conservatively in Nigeria. Gwagwalada, Abuja. Over a 1-year period (1 January 2009 to 31 December 2009), the cost of ASCI of consecutive spinal cord-injured patients, gainfully employed preinjury, who paid the hospital bill directly from their purses and could estimate their daily income, and who were managed conservatively for 6 weeks before discharge to rehabilitation, was prospectively examined. A total of 34 cases of spinal cord-injured patients with a mean age of 35.4 ± 12.8 years were included in this study. The mean cost of ASCI over 6 weeks was $1598.29, an average of 6.4-232.8% of patients' annual income where >50% of the people live on less than a dollar a day. The mean cost of hospitalization was 14.9% of the total cost of ASCI in this study. It was significantly more expensive to treat tetraplegics compared with paraplegics. This study identified the cost of acute phase of spinal cord injury in Nigeria to assist clinicians in planning treatment that could reduce financial burden on the patients but optimize patients' care.

Electromagnetic interference of mobile phones with electronic implants

International Nuclear Information System (INIS)

Kainz, W.

2000-03-01

Chapter 1:Interference matrix: The objective of Chapter 1 was to give an overview of the implants used at present and their electromagnetic compatibility (EMC). The evaluation of the available literature provides an estimate of the probability of electronic implants being influenced by various interference sources. A literature search at the AKH (Allgemeines Krankenhaus) in Vienna and at the Technical University of Vienna in the FIZ (Fach-Informations-Zentrum) -Biomedizinische Technik, Medline, Pascal Biomed, CC Search und Embase databases yielded 236 relevant publications. At present 12 different implants are used: pacemaker, defibrillator, cochlear and brain-stem implants, neurostimulators, spinal-cord stimulators, spinal-fusion stimulators, telemetry systems, artificial hearts, drug-delivery systems, neurological pulse generators, visual prosthetics and implantable patient chips. The frequency with which they are used and the EMC on exposure to the various interference sources was summarized. Publications on EMC were found only for the first six implant types and only for 30% of the possible combinations of implant type and interference source. Based on the number of the implants examined, the probability of interference was calculated and summarized in the interference matrix. Chapter 2:Measurements on the phantom: No publication on the electromagnetic compatibility of neurological pulse generators (NPG) could be found. This implant has been used increasingly in the last few years to treat Parkinson's disease. A phantom was built to examine this implant at 900 MHz. The electromagnetic compatibility was measured by exposing the NPG to the fields of ten different 900 MHz GSM mobile phones. Every mobile phone was tested in three different positions relative to the phantom, with four electrode configurations and four stimulation parameters. No interference was found even at a maximum transmit power of 2 watts. Further tests with half-wave dipoles and increased

Dosimetric measurement of scattered radiation from dental implants in simulated head and neck radiotherapy.

Science.gov (United States)

Wang, R; Pillai, K; Jones, P K

1998-01-01

The purpose of this study was to examine the dose enhancement at bone-implant interfaces from scattered radiation during simulated head and neck radiotherapy. Three cylindric implant systems with different compositions (pure titanium, titanium-aluminum-vanadium alloy, titanium coated with hydroxyapatite) and a high gold content transmandibular implant system (gold-copper-silver alloy) were studied. Extruded lithium fluoride single crystal chips were used as thermoluminescent material to measure radiation dose enhancement at 0, 1, and 2 mm from the bone-implant interface. The relative doses in buccal, lingual, mesial, and distal directions were also recorded and compared. The results indicated that the highest dose enhancement occurred at a distance of 0 mm from the bone-implant interface for all the implant systems studied. The transmandibular implants had higher scattered radiation than other groups at 0 mm and at 1 mm from the bone-implant interface. There was no significant difference of dose enhancement between buccal, lingual, mesial, and distal directions. Titanium implants coated with hydroxyapatite demonstrated the best results under the simulated irradiation.

Functional Brain Connectivity during Multiple Motor Imagery Tasks in Spinal Cord Injury

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Alkinoos Athanasiou

2018-01-01

Full Text Available Reciprocal communication of the central and peripheral nervous systems is compromised during spinal cord injury due to neurotrauma of ascending and descending pathways. Changes in brain organization after spinal cord injury have been associated with differences in prognosis. Changes in functional connectivity may also serve as injury biomarkers. Most studies on functional connectivity have focused on chronic complete injury or resting-state condition. In our study, ten right-handed patients with incomplete spinal cord injury and ten age- and gender-matched healthy controls performed multiple visual motor imagery tasks of upper extremities and walking under high-resolution electroencephalography recording. Directed transfer function was used to study connectivity at the cortical source space between sensorimotor nodes. Chronic disruption of reciprocal communication in incomplete injury could result in permanent significant decrease of connectivity in a subset of the sensorimotor network, regardless of positive or negative neurological outcome. Cingulate motor areas consistently contributed the larger outflow (right and received the higher inflow (left among all nodes, across all motor imagery categories, in both groups. Injured subjects had higher outflow from left cingulate than healthy subjects and higher inflow in right cingulate than healthy subjects. Alpha networks were less dense, showing less integration and more segregation than beta networks. Spinal cord injury patients showed signs of increased local processing as adaptive mechanism. This trial is registered with NCT02443558.

Direct measurement of cerebrospinal fluid pressure through the cochlea in a congenitally deaf child with Mondini dysplasia undergoing cochlear implantation.

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Graham, J M; Ashcroft, P

1999-03-01

Perilymph/cerebrospinal fluid (CSF) "gushers" may occur at cochleostomy during cochlear implant surgery, particularly in patients with congenital cochlear duct malformation in which CSF in the internal auditory meatus is in direct communication with the perilymphatic space in the cochlea. The object of the study was to measure the pressure and flow of a CSF gusher at cochleostomy. The design was a preoperative pressure measurement. The setting was a multidisciplinary cochlear implant program. A 4-year-old girl with bilateral Mondini deformity undergoing cochlear implantation was studied. A size 23 FG intravenous cannula was inserted into the cochlea and connected to a pediatric drip set to form an improvised manometer. Intracochlear fluid pressure was measured at 14 cm H2O, equivalent to the normal CSF pressure that would be recorded in a child of this age at lumbar puncture. An indirect measurement of the likely size of the CSF/perilymph defect was made. This technique may allow better assessment of the risk of postoperative CSF leakage and meningitis. This simple technique of measuring the pressure in a perilymph gusher can be used to assess the need for careful sealing of the cochleostomy, to measure the reduction in pressure produced by head elevation or a spinal drain, and to assess the probable size of a defect in the lamina cribrosa.

Rapid recovery and altered neurochemical dependence of locomotor central pattern generation following lumbar neonatal spinal cord injury.

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Züchner, Mark; Kondratskaya, Elena; Sylte, Camilla B; Glover, Joel C; Boulland, Jean-Luc

2018-01-15

Spinal compression injury targeted to the neonatal upper lumbar spinal cord, the region of highest hindlimb locomotor rhythmogenicity, leads to an initial paralysis of the hindlimbs. Behavioural recovery is evident within a few days and approaches normal function within about 3 weeks. Fictive locomotion in the isolated injured spinal cord cannot be elicited by a neurochemical cocktail containing NMDA, dopamine and serotonin 1 day post-injury, but can 3 days post-injury as readily as in the uninjured spinal cord. Low frequency coordinated rhythmic activity can be elicited in the isolated uninjured spinal cord by NMDA + dopamine (without serotonin), but not in the isolated injured spinal cord. In both the injured and uninjured spinal cord, eliciting bona fide fictive locomotion requires the additional presence of serotonin. Following incomplete compression injury in the thoracic spinal cord of neonatal mice 1 day after birth (P1), we previously reported that virtually normal hindlimb locomotor function is recovered within about 3 weeks despite substantial permanent thoracic tissue loss. Here, we asked whether similar recovery occurs following lumbar injury that impacts more directly on the locomotor central pattern generator (CPG). As in thoracic injuries, lumbar injuries caused about 90% neuronal loss at the injury site and increased serotonergic innervation below the injury. Motor recovery was slower after lumbar than thoracic injury, but virtually normal function was attained by P25 in both cases. Locomotor CPG status was tested by eliciting fictive locomotion in isolated spinal cords using a widely used neurochemical cocktail (NMDA, dopamine, serotonin). No fictive locomotion could be elicited 1 day post-injury, but could within 3 days post-injury as readily as in age-matched uninjured control spinal cords. Burst patterning and coordination were largely similar in injured and control spinal cords but there were differences. Notably, in both groups there

2D FEA of evaluation of micromovements and stresses at bone-implant interface in immediately loaded tapered implants in the posterior maxilla

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Shrikar R Desai

2013-01-01

Full Text Available Aim: The aim of the study is to evaluate the influence implant length on stress distribution at bone implant interface in single immediately loaded implants when placed in D4 bone quality. Materials and Methods: A 2-dimensional finite element models were developed to simulate two types of implant designs, standard 3.75 mm-diameter tapered body implants of 6 and 10 mm lengths. The implants were placed in D4 bone quality with a cortical bone thickness of 0.5 mm. The implant design incorporated microthreads at the crestal part and the rest of the implant body incorporated Acme threads. The Acme thread form has a 29° thread angle with a thread height half of the pitch; the apex and valley are flat. A 100 N of force was applied vertically and in the oblique direction (at an angle of 45° to the long axis of the implants. The respective material properties were assigned. Micro-movements and stresses at the bone implant interface were evaluated. Results: The results of total deformation (micro-movement and Von mises stress were found to be lower for tapered long implant (10 mm than short implant (6 mm while using both vertical as well as oblique loading. Conclusion: Short implants can be successfully placed in poor bone quality under immediate loading protocol. The novel approach of the combination of microthreads at the crestal portion and acme threads for body portion of implant fixture gave promising results.

2D FEA of evaluation of micromovements and stresses at bone-implant interface in immediately loaded tapered implants in the posterior maxilla.

Science.gov (United States)

Desai, Shrikar R; Singh, Rika; Karthikeyan, I

2013-09-01

The aim of the study is to evaluate the influence implant length on stress distribution at bone implant interface in single immediately loaded implants when placed in D4 bone quality. A 2-dimensional finite element models were developed to simulate two types of implant designs, standard 3.75 mm-diameter tapered body implants of 6 and 10 mm lengths. The implants were placed in D4 bone quality with a cortical bone thickness of 0.5 mm. The implant design incorporated microthreads at the crestal part and the rest of the implant body incorporated Acme threads. The Acme thread form has a 29° thread angle with a thread height half of the pitch; the apex and valley are flat. A 100 N of force was applied vertically and in the oblique direction (at an angle of 45°) to the long axis of the implants. The respective material properties were assigned. Micro-movements and stresses at the bone implant interface were evaluated. The results of total deformation (micro-movement) and Von mises stress were found to be lower for tapered long implant (10 mm) than short implant (6 mm) while using both vertical as well as oblique loading. Short implants can be successfully placed in poor bone quality under immediate loading protocol. The novel approach of the combination of microthreads at the crestal portion and acme threads for body portion of implant fixture gave promising results.

Influence of simulated bone-implant contact and implant diameter on secondary stability: a resonance frequency in vitro study.

Science.gov (United States)

Veltri, Mario; González-Martín, Oscar; Belser, Urs C

2014-08-01

This study tested the hypothesis of no differences in resonance frequency for standardized amounts of simulated bone-implant contact around implants with different diameters. In addition, it was evaluated if resonance frequency is able to detect a difference between stable and rotation mobile ("spinning") implants. Implants with diameters of 3.3, 4.1 and 4.8 mm were placed in a purposely designed metal mould where liquid polyurethane resin was then poured to obtain a simulated bone-implant specimen. By regulating the mould, it was possible to create the following simulated bone-implant contact groups: 3.3 mm (198.6 mm(2)); 4.1 mm (198.8 mm(2)); 4.8 mm (200.2 mm(2)); 4.8 mm (231.7 mm(2)); 4.8 mm (294.7 mm(2)). Each group included 10 specimens. After resin setting, resonance frequency was measured. On the last group, measurements were repeated after establishing implant rotational mobility. One-way ANOVA tests with post hoc comparisons, a Pearson's correlation coefficient and a t-test for repeated measurements were used to evaluate statistically significant differences. Implants with different diameters but with the same amount of simulated osseointegration revealed no differences in resonance frequency. On the contrary, an increase of simulated bone-implant contact resulted in significantly higher resonance frequency. A clear direct linear correlation resulted between resonance frequency and simulated bone-implant contact. Furthermore, a significant difference resulted between resonance frequency measured before and after creation of rotational mobility. Within the conditions of this study, the secondary stability was correlated with the simulated bone-implant contact. In addition, resonance frequency was able to discern between stable and rotation mobile implants. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Computed tomography in cervical spondylotic myelopathy and radiculopathy: Visualisation of structures, myelographic comparison, cord measurements and clinical utility

International Nuclear Information System (INIS)

Yu, Y.L.; Du Boulay, G.H.; Stevens, J.M.; Kendall, B.E.

1986-01-01

Sixty-nine patients with cervical spondylotic myelopathy (CSM), radiculopathy (CSR), or both (CSMR) were studied with computed tomography (CT). Computer-assisted myelography (CAM) accurately determines the site and nature of spondylotic protrusions and provides good visualisation of the subarachnoid space and cord deformities even in areas with dilute metrizamide. However, excessive vertebral movement and bulging ligamenta flava with their effects on cord deformity, so easily visualised in myelograms, are completely or partially missed. In the assessment of CSM, metrizamide myelography (MM) followed by CAM should be performed, particularly when the myelographic images are unsatisfactory due to contrast dilution or blockage, when cord compression cannot be ascertained with MM and when cord atrophy is suspected. In CSR, the diagnostic information from MM and CAM is comparable. The diagnostic criteria in CAM are, however, less direct and since MM is adequate in uncomplicated cases, CAM is generally not necessary. The APD, APD/TD ratio, area and circularity are sensitive indices of cord deformity and the first two should be used more often to assist visual assessment of cord deformity. The relation between cord parameters and treatment response is better reflected in CSM cases managed conservatively and the results suggest that the degree of cord deformity is helpful in determining the outcome and hence the choice between surgical and conservative treatment. In plain CT, the osteophytes and calcified discs are adequately visualised and canal dimensions measured with accuracy, but the cervical cord and roots cannot be properly assessed and the diagnosis of CSM or CSR cannot be ascertained. At present, its role in cervical spondylosis is therefore limited. (orig.)

Isolation of mesenchymal stem cells from equine umbilical cord blood

DEFF Research Database (Denmark)

Koch, Thomas Gadegaard; Heerkens, Tammy; Thomsen, Preben Dybdahl

2007-01-01

. The hypothesis of this study was that equine MSCs could be isolated from fresh whole equine cord blood. Results: Cord blood was collected from 7 foals immediately after foaling. The mononuclear cell fraction was isolated by Ficoll density centrifugation and cultured in a DMEM low glucose based media at 38.5o......Background: There are no published studies on stem cells from equine cord blood although commercial storage of equine cord blood for future autologous stem cell transplantations is available. Mesenchymal stem cells (MSC) have been isolated from fresh umbilical cord blood of humans collected non......-invasively at the time of birth and from sheep cord blood collected invasively by a surgical intrauterine approach. Mesenchymal stem cells isolation percentage from frozen-thawed human cord blood is low and the future isolation percentage of MSCs from cryopreserved equine cord blood is therefore expectedly low...

Optimizing Filter-Probe Diffusion Weighting in the Rat Spinal Cord for Human Translation

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Matthew D. Budde

2017-12-01

Full Text Available Diffusion tensor imaging (DTI is a promising biomarker of spinal cord injury (SCI. In the acute aftermath, DTI in SCI animal models consistently demonstrates high sensitivity and prognostic performance, yet translation of DTI to acute human SCI has been limited. In addition to technical challenges, interpretation of the resulting metrics is ambiguous, with contributions in the acute setting from both axonal injury and edema. Novel diffusion MRI acquisition strategies such as double diffusion encoding (DDE have recently enabled detection of features not available with DTI or similar methods. In this work, we perform a systematic optimization of DDE using simulations and an in vivo rat model of SCI and subsequently implement the protocol to the healthy human spinal cord. First, two complementary DDE approaches were evaluated using an orientationally invariant or a filter-probe diffusion encoding approach. While the two methods were similar in their ability to detect acute SCI, the filter-probe DDE approach had greater predictive power for functional outcomes. Next, the filter-probe DDE was compared to an analogous single diffusion encoding (SDE approach, with the results indicating that in the spinal cord, SDE provides similar contrast with improved signal to noise. In the SCI rat model, the filter-probe SDE scheme was coupled with a reduced field of view (rFOV excitation, and the results demonstrate high quality maps of the spinal cord without contamination from edema and cerebrospinal fluid, thereby providing high sensitivity to injury severity. The optimized protocol was demonstrated in the healthy human spinal cord using the commercially-available diffusion MRI sequence with modifications only to the diffusion encoding directions. Maps of axial diffusivity devoid of CSF partial volume effects were obtained in a clinically feasible imaging time with a straightforward analysis and variability comparable to axial diffusivity derived from DTI

Microstructural and Mechanical Characterization of a Custom-Built Implant Manufactured in Titanium Alloy by Direct Metal Laser Sintering

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Maria Aparecida Larosa

2014-08-01

Full Text Available Custom-built implants manufacture has always presented difficulties which result in high cost and complex fabrication, mainly due to patients’ anatomical differences. The solution has been to produce prostheses with different sizes and use the one that best suits each patient. Additive manufacturing technology, incorporated into the medical field in the late 80's, has made it possible to obtain solid biomodels facilitating surgical procedures and reducing risks. Furthermore, this technology has been used to produce implants especially designed for a particular patient, with sizes, shapes, and mechanical properties optimized, for different areas of medicine such as craniomaxillofacial surgery. In this work, the microstructural and mechanical properties of Ti6Al4V samples produced by direct metal laser sintering (DMLS are studied. The microstructural and mechanical characterizations have been made by optical and scanning electron microscopy, X-ray diffraction, and microhardness and tensile tests. Samples produced by DMLS have a microstructure constituted by hexagonal α′ martensite with acicular morphology. An average microhardness of 370 HV was obtained and the tensile tests showed ultimate strength of 1172 MPa, yield strength of 957 MPa, and elongation at rupture of 11%.

Diffusion tensor imaging in spinal cord compression

International Nuclear Information System (INIS)

Wang, Wei; Qin, Wen; Hao, Nanxin; Wang, Yibin; Zong, Genlin

2012-01-01

Background Although diffusion tensor imaging has been successfully applied in brain research for decades, several main difficulties have hindered its extended utilization in spinal cord imaging. Purpose To assess the feasibility and clinical value of diffusion tensor imaging and tractography for evaluating chronic spinal cord compression. Material and Methods Single-shot spin-echo echo-planar DT sequences were scanned in 42 spinal cord compression patients and 49 healthy volunteers. The mean values of the apparent diffusion coefficient and fractional anisotropy were measured in region of interest at the cervical and lower thoracic spinal cord. The patients were divided into two groups according to the high signal on T2WI (the SCC-HI group and the SCC-nHI group for with or without high signal). A one-way ANOVA was used. Diffusion tensor tractography was used to visualize the morphological features of normal and impaired white matter. Results There were no statistically significant differences in the apparent diffusion coefficient and fractional anisotropy values between the different spinal cord segments of the normal subjects. All of the patients in the SCC-HI group had increased apparent diffusion coefficient values and decreased fractional anisotropy values at the lesion level compared to the normal controls. However, there were no statistically significant diffusion index differences between the SCC-nHI group and the normal controls. In the diffusion tensor imaging maps, the normal spinal cord sections were depicted as fiber tracts that were color-encoded to a cephalocaudal orientation. The diffusion tensor images were compressed to different degrees in all of the patients. Conclusion Diffusion tensor imaging and tractography are promising methods for visualizing spinal cord tracts and can provide additional information in clinical studies in spinal cord compression

MR imaging of stable posttraumatic spinal cord injury

International Nuclear Information System (INIS)

Braun, I.F.; Hoffman, J.C. Jr.; Murphy, C.; Davis, P.C.

1986-01-01

Posttraumatic spinal cord cysts have been thought to be infrequent sequelae of spinal trauma. To evaluate the incidence of spinal cord abnormalities in patients who have previously sustained cord trauma, the authors studied the incidence of these changes in clinically stable patients following injury. Twenty-five patients with a history of previous cord injury and stable neurologic status volunteered for MR imaging studies. Studies performed using a 0.5-T and 1.5-T unit revealed focal kinking of the cord at the trauma site as well as intramedullary hypointense areas on T1-weighted images in most volunteers. There was close clinical correlation between MR imaging findings and experimental pathologic data, which suggests that these lesions are much more prevalent than once thought

Transplante de sangue de cordão umbilical - SCU Umbilical cord blood transplantation

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Celso A. Rodrigues

2010-05-01

Full Text Available A frequente utilização de sangue de cordão umbilical - SCU como fonte de células- tronco hematopoéticas - CTH, tanto em crianças, como em adultos, que não dispõem de doador na família, tem levado ao estabelecimento da padronização de critérios em sua seleção, objetivando a obtenção de melhores resultados. A escolha da unidade de SCU deve basear-se no número total de células nucleadas e no número de diferenças de antígenos leucocitários humanos (HLA. Diante de uma unidade com celularidade mínima, deve-se considerar a possibilidade da utilização de duplo cordão. Frente a mais de uma unidade com características semelhantes, a realização da contagem de células CD34 e da compatibilidade ABO, assim como a qualidade e a rapidez para obtenção da unidade, podem definir a escolha.The frequent use of umbilical cord blood as the source of hematopoietic stem cells, both in children and adults who do not have related donors, has led to the establishment of a better standardization of selection criteria aiming at improving the results. The choice of the umbilical cord blood unit should be based on the total number of nucleated cells and the number of differences in the human leukocyte antigen (HLA system. When a unit has minimal cellularity, the use of a double cord blood transplant should be considered. When two or more units have similar characteristics, the choice may be determined by the CD34 count, ABO compatibility and the quality and speed to obtain the unit.

Tolerance of the human spinal cord to single dose radiosurgery

International Nuclear Information System (INIS)

Ryu, S.; Zhu, G.; Yin, F.-F.; Ajlouni, M.; Kim, J.H.

2003-01-01

Tolerance of the spinal cord to the single dose of radiation is not well defined. Although there are cases of human spinal cord tolerance from re-irradiation to the same cord level, the information about the tolerance of human spinal cord to single large dose of radiosurgery is not available. We carried out spinal radiosurgery to treat spinal metastasis and studied the single dose tolerance of the human spinal cord in an ongoing dose escalation paradigm. A total of 39 patients with 48 lesions of spinal metastasis were treated with single dose radiosurgery at Henry Ford Hospital. The radiosurgery dose was escalated from 8 Gy to 16 Gy at 2 Gy increment. The radiation dose was prescribed to periphery of the spinal tumor. The radiation dose to the spinal cord was estimated by computerized dosimetry. The median follow-up time was 10 months (range 6-18 months) from the radiosurgery. The endpoint of the study was to demonstrate the efficacy of the spinal radiosurgery and to determine the tolerance of human spinal cord to single dose radiosurgery. The dose to the spinal cord was generally less than 50 % of the prescribed radiation dose. The volume of the spinal cord that received higher than this dose was less than 20 % of the anterior portion of the spinal cord. Maximum single dose of 8 Gy was delivered to the anterior 20 % of the spinal cord in this dose escalation study. The dose volume histogram will be presented. There was no acute or subacute radiation toxicity detected clinically and radiologically during the maximum follow-up of 20 months. Further dose escalation is in progress. The single tolerance dose of the human spinal cord appears to be at least 8 Gy when it was given to the 20 % of the cord volume, although the duration of follow up is not long enough to detect severe late cord toxicity. This study offers a valuable radiobiological basis of the normal spinal cord tolerance, and opens spinal radiosurgery as a safe treatment for spinal metastasis

Spermatic Cord Knot: A Clinical Finding in Patients with Spermatic Cord Torsion

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Abdullatif Al-Terki

2011-01-01

Full Text Available Pertinent history taking and careful examination often taper the differentials of the acute scrotum; congruently the ability to diagnose acute spermatic cord torsion (SCT when radiological adjuncts are not available is highly imperative. This observational study serves to present a series of 46 cases of spermatic cord torsion whereby we hypothesize the identification of a clinical knot on scrotal examination as an important clinical aid in making a decision to surgical exploration in patients with acute and subacute SCT, especially in centers where imaging resources are unavailable.

Pudendal nerve stimulation and block by a wireless-controlled implantable stimulator in cats.

Science.gov (United States)

Yang, Guangning; Wang, Jicheng; Shen, Bing; Roppolo, James R; de Groat, William C; Tai, Changfeng

2014-07-01

The study aims to determine the functionality of a wireless-controlled implantable stimulator designed for stimulation and block of the pudendal nerve. In five cats under α-chloralose anesthesia, the stimulator was implanted underneath the skin on the left side in the lower back along the sacral spine. Two tripolar cuff electrodes were implanted bilaterally on the pudendal nerves in addition to one bipolar cuff electrode that was implanted on the left side central to the tripolar cuff electrode. The stimulator provided high-frequency (5-20 kHz) biphasic stimulation waveforms to the two tripolar electrodes and low-frequency (1-100 Hz) rectangular pulses to the bipolar electrode. Bladder and urethral pressures were measured to determine the effects of pudendal nerve stimulation (PNS) or block. The maximal (70-100 cmH2O) urethral pressure generated by 20-Hz PNS applied via the bipolar electrode was completely eliminated by the pudendal nerve block induced by the high-frequency stimulation (6-15 kHz, 6-10 V) applied via the two tripolar electrodes. In a partially filled bladder, 20-30 Hz PNS (2-8 V, 0.2 ms) but not 5 Hz stimulation applied via the bipolar electrode elicited a large sustained bladder contraction (45.9 ± 13.4 to 52.0 ± 22 cmH2O). During cystometry, the 5 Hz PNS significantly (p < 0.05) increased bladder capacity to 176.5 ± 27.1% of control capacity. The wireless-controlled implantable stimulator successfully generated the required waveforms for stimulation and block of pudendal nerve, which will be useful for restoring bladder functions after spinal cord injury. © 2013 International Neuromodulation Society.

Transplantation of mononuclear cells from human umbilical cord blood promotes functional recovery after traumatic spinal cord injury in Wistar rats

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Rodrigues, L.P.; Iglesias, D.; Nicola, F.C.; Steffens, D.; Valentim, L.; Witczak, A.; Zanatta, G.; Achaval, M.; Pranke, P.; Netto, C.A.

2011-01-01

Cell transplantation is a promising experimental treatment for spinal cord injury. The aim of the present study was to evaluate the efficacy of mononuclear cells from human umbilical cord blood in promoting functional recovery when transplanted after a contusion spinal cord injury. Female Wistar rats (12 weeks old) were submitted to spinal injury with a MASCIS impactor and divided into 4 groups: control, surgical control, spinal cord injury, and one cell-treated lesion group. Mononuclear cells from umbilical cord blood of human male neonates were transplanted in two experiments: a) 1 h after surgery, into the injury site at a concentration of 5 x 10 6 cells diluted in 10 µL 0.9% NaCl (N = 8-10 per group); b) into the cisterna magna, 9 days after lesion at a concentration of 5 x 10 6 cells diluted in 150 µL 0.9% NaCl (N = 12-14 per group). The transplanted animals were immunosuppressed with cyclosporin-A (10 mg/kg per day). The BBB scale was used to evaluate motor behavior and the injury site was analyzed with immunofluorescent markers to label human transplanted cells, oligodendrocytes, neurons, and astrocytes. Spinal cord injury rats had 25% loss of cord tissue and cell treatment did not affect lesion extension. Transplanted cells survived in the injured area for 6 weeks after the procedure and both transplanted groups showed better motor recovery than the untreated ones (P < 0.05). The transplantation of mononuclear cells from human umbilical cord blood promoted functional recovery with no evidence of cell differentiation

Transplantation of mononuclear cells from human umbilical cord blood promotes functional recovery after traumatic spinal cord injury in Wistar rats

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Rodrigues, L.P. [Programa de Pós-Graduação em Neurociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Iglesias, D. [Laboratório de Hematologia e Células-Tronco, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Nicola, F.C. [Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Steffens, D. [Laboratório de Hematologia e Células-Tronco, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Valentim, L.; Witczak, A.; Zanatta, G. [Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Achaval, M. [Departamento de Ciências Morfológicas, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Pranke, P. [Laboratório de Hematologia e Células-Tronco, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Netto, C.A. [Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil)

2011-12-23

Cell transplantation is a promising experimental treatment for spinal cord injury. The aim of the present study was to evaluate the efficacy of mononuclear cells from human umbilical cord blood in promoting functional recovery when transplanted after a contusion spinal cord injury. Female Wistar rats (12 weeks old) were submitted to spinal injury with a MASCIS impactor and divided into 4 groups: control, surgical control, spinal cord injury, and one cell-treated lesion group. Mononuclear cells from umbilical cord blood of human male neonates were transplanted in two experiments: a) 1 h after surgery, into the injury site at a concentration of 5 x 10{sup 6} cells diluted in 10 µL 0.9% NaCl (N = 8-10 per group); b) into the cisterna magna, 9 days after lesion at a concentration of 5 x 10{sup 6} cells diluted in 150 µL 0.9% NaCl (N = 12-14 per group). The transplanted animals were immunosuppressed with cyclosporin-A (10 mg/kg per day). The BBB scale was used to evaluate motor behavior and the injury site was analyzed with immunofluorescent markers to label human transplanted cells, oligodendrocytes, neurons, and astrocytes. Spinal cord injury rats had 25% loss of cord tissue and cell treatment did not affect lesion extension. Transplanted cells survived in the injured area for 6 weeks after the procedure and both transplanted groups showed better motor recovery than the untreated ones (P < 0.05). The transplantation of mononuclear cells from human umbilical cord blood promoted functional recovery with no evidence of cell differentiation.

Simplified spinal cord phantom for evaluation of SQUID magnetospinography

International Nuclear Information System (INIS)

Adachi, Y; Oyama, D; Uehara, G; Somchai, N; Kawabata, S

2014-01-01

Spinal cord functional imaging by magnetospinography (MSG) is a noninvasive diagnostic method for spinal cord diseases. However, the accuracy and spatial resolution of lesion localization by MSG have barely been evaluated in detail so far. We developed a simplified spinal cord phantom for MSG evaluation. The spinal cord phantom is composed of a cylindrical vessel filled with saline water, which acts as a model of a neck. A set of modeled vertebrae is arranged in the cylindrical vessel, which has a neural current model made from catheter electrodes. The neural current model emulates the current distribution around the activated site along the axon of the spinal cord nerve. Our MSG system was used to observe the magnetic field from the phantom; a quadrupole-like pattern of the magnetic field distribution, which is a typical distribution pattern for spinal cord magnetic fields, was successfully reproduced by the phantom. Hence, the developed spinal cord phantom can be used to evaluate MSG source analysis methods.

Evoked EMG-based torque prediction under muscle fatigue in implanted neural stimulation

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Hayashibe, Mitsuhiro; Zhang, Qin; Guiraud, David; Fattal, Charles

2011-10-01

In patients with complete spinal cord injury, fatigue occurs rapidly and there is no proprioceptive feedback regarding the current muscle condition. Therefore, it is essential to monitor the muscle state and assess the expected muscle response to improve the current FES system toward adaptive force/torque control in the presence of muscle fatigue. Our team implanted neural and epimysial electrodes in a complete paraplegic patient in 1999. We carried out a case study, in the specific case of implanted stimulation, in order to verify the corresponding torque prediction based on stimulus evoked EMG (eEMG) when muscle fatigue is occurring during electrical stimulation. Indeed, in implanted stimulation, the relationship between stimulation parameters and output torques is more stable than external stimulation in which the electrode location strongly affects the quality of the recruitment. Thus, the assumption that changes in the stimulation-torque relationship would be mainly due to muscle fatigue can be made reasonably. The eEMG was proved to be correlated to the generated torque during the continuous stimulation while the frequency of eEMG also decreased during fatigue. The median frequency showed a similar variation trend to the mean absolute value of eEMG. Torque prediction during fatigue-inducing tests was performed based on eEMG in model cross-validation where the model was identified using recruitment test data. The torque prediction, apart from the potentiation period, showed acceptable tracking performances that would enable us to perform adaptive closed-loop control through implanted neural stimulation in the future.

Neuroimaging for spine and spinal cord surgery

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Koyanagi, Izumi [Hokkaido Neurosurgical Memorial Hospital (Japan); Iwasaki, Yoshinobu; Hida, Kazutoshi

2001-01-01

Recent advances in neuroimaging of the spine and spinal cord are described based upon our clinical experiences with spinal disorders. Preoperative neuroradiological examinations, including magnetic resonance (MR) imaging and computerized tomography (CT) with three-dimensional reconstruction (3D-CT), were retrospectively analyzed in patients with cervical spondylosis or ossification of the posterior longitudinal ligament (130 cases), spinal trauma (43 cases) and intramedullary spinal cord tumors (92 cases). CT scan and 3D-CT were useful in elucidating the spine pathology associated with degenerative and traumatic spine diseases. Visualization of the deformity of the spine or fracture-dislocation of the spinal column with 3D-CT helped to determine the correct surgical treatment. MR imaging was most important in the diagnosis of both spine and spinal cord abnormalities. The axial MR images of the spinal cord were essential in understanding the laterality of the spinal cord compression in spinal column disorders and in determining surgical approaches to the intramedullary lesions. Although non-invasive diagnostic modalities such as MR imaging and CT scans are adequate for deciding which surgical treatment to use in the majority of spine and spinal cord disorders, conventional myelography is still needed in the diagnosis of nerve root compression in some cases of cervical spondylosis. (author)

Central nociceptive sensitization vs. spinal cord training: Opposing forms of plasticity that dictate function after complete spinal cord injury

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Adam R Ferguson

2012-10-01

Full Text Available The spinal cord demonstrates several forms of plasticity that resemble brain-dependent learning and memory. Among the most studied form of spinal plasticity is spinal memory for noxious (nociceptive stimulation. Numerous papers have described central pain as a spinally-stored memory that enhances future responses to cutaneous stimulation. This phenomenon, known as central sensitization, has broad relevance to a range of pathological conditions. Work from the spinal cord injury (SCI field indicates that the lumbar spinal cord demonstrates several other forms of plasticity, including formal learning and memory. After complete thoracic SCI, the lumbar spinal cord can be trained by delivering stimulation to the hindleg when the leg is extended. In the presence of this response-contingent stimulation the spinal cord rapidly learns to hold the leg in a flexed position, a centrally mediated effect that meets the formal criteria for instrumental (response-outcome learning. Instrumental flexion training produces a central change in spinal plasticity that enables future spinal learning on both the ipsilateral and contralateral leg. However, if stimulation is given in a response-independent manner, the spinal cord develops central maladaptive plasticity that undermines future spinal learning on both legs. The present paper tests for interactions between spinal cord training and central nociceptive sensitization after complete spinal cord transection. We found that spinal training alters future central sensitization by intradermal formalin (24 h post-training. Conversely intradermal formalin impaired future spinal learning (24 h post-injection. Because the NMDA receptor has been implicated in formalin-induced central sensitization, we tested whether pretreatment with NMDA affects spinal learning. We found intrathecal NMDA impaired learning in a dose-dependent fashion, and that this effect endures for at least 24h. These data provide strong evidence for an

Biomechanical effects of spinal cord compression due to ossification of posterior longitudinal ligament and ligamentum flavum: a finite element analysis.

Science.gov (United States)

Kim, Yoon Hyuk; Khuyagbaatar, Batbayar; Kim, Kyungsoo

2013-09-01

Ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum (OLF) have been recognized as causes of myelopathy due to thickening of the ligaments resulting in narrowing of the spinal canal and compression of the spinal cord. However, few studies have focused on predicting stress distribution under conditions of OPLL and OLF based on clinical aspects such as the relationship between level of stress and severity of neurologic symptoms because direct in vivo measurement of stress is very restrictive. In this study, a three-dimensional finite element model of the spinal cord in T12-L1 was developed based on MR images. The von-Mises stresses in the cord and the cross-sectional area of the cord were investigated for various grades and shapes of spinal cord compression in OPLL and OLF. Substantial increases in maximum stresses resulting in the manifestation of spinal cord symptoms occurred when the cross-sectional area was reduced by 30-40% at 60% compression of the antero-posterior diameter of the cord in OPLL and at 4mm compression in OLF. These results indicate that compression greater than these thresholds may induce spinal symptoms, which is consistent with clinical observations. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.

Radiological diagnosis of chronic spinal cord compressive lesion at thoraco-lumbar junction

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Koyanagi, Izumi; Isu, Toyohiko; Iwasaki, Yoshinobu; Akino, Minoru; Abe, Hiroshi; Tashiro, Kunio; Miyasaka, Kazuo; Abe, Satoru; Kaneda, Kiyoshi

1988-10-01

Radiological findings in five cases with chronic spinal cord compressive lesion at thoraco-lumbar junction were reported. Three cases had spondylosis and two cases had ossification of yellow ligament (OYL). The levels of the lesions were T12/L1 in three cases and T11/12 in two cases. Two out of three spondylotic patients had also OYL at the same level. The five cases consisted of three men and two women. The ages ranged from 42 to 60 years old with a mean age of 53 years old. Neurologically, every patient showed flaccid paresis and sensory disturbance of the legs. Two cases had sensory disturbance of stocking type. The intervals from the onset of the symptoms to the final diagnosis were 6 months, 7 years, 8 years, 11 years and 12 years. Myelography showed anterior spinal cord compression by bony spur in spondylotic patients, and posterior compression by OYL in other cases. Myelography in flexion posture disclosed the cord compression by bony spur more clearly in two out of three spondylotic patients. Delayed CT-myelography showed intramedullary filling of contrast material in two cases, which indicated degenerative change or microcavitation due to long term compression of the spinal cord. MRI was taken in three spondylotic patients and could directly show compression of the spinal cord. Difficulty in detecting abnormality at thoraco-lumbar junction on plain roentgenogram, and similarity of the symptoms to peripheral nerve disease often lead to a delay in diagnosis. The significance of dynamic myelography and delayed CT-myelography when dealing with such a lesion was discussed here. MRI is also a useful method for diagnosing a compressive lesion at the thoraco-lumbar junction.

Radiological diagnosis of chronic spinal cord compressive lesion at thoraco-lumbar junction

International Nuclear Information System (INIS)

Koyanagi, Izumi; Isu, Toyohiko; Iwasaki, Yoshinobu; Akino, Minoru; Abe, Hiroshi; Tashiro, Kunio; Miyasaka, Kazuo; Abe, Satoru; Kaneda, Kiyoshi

1988-01-01

Radiological findings in five cases with chronic spinal cord compressive lesion at thoraco-lumbar junction were reported. Three cases had spondylosis and two cases had ossification of yellow ligament (OYL). The levels of the lesions were T12/L1 in three cases and T11/12 in two cases. Two out of three spondylotic patients had also OYL at the same level. The five cases consisted of three men and two women. The ages ranged from 42 to 60 years old with a mean age of 53 years old. Neurologically, every patient showed flaccid paresis and sensory disturbance of the legs. Two cases had sensory disturbance of stocking type. The intervals from the onset of the symptoms to the final diagnosis were 6 months, 7 years, 8 years, 11 years and 12 years. Myelography showed anterior spinal cord compression by bony spur in spondylotic patients, and posterior compression by OYL in other cases. Myelography in flexion posture disclosed the cord compression by bony spur more clearly in two out of three spondylotic patients. Delayed CT-myelography showed intramedullary filling of contrast material in two cases, which indicated degenerative change or microcavitation due to long term compression of the spinal cord. MRI was taken in three spondylotic patients and could directly show compression of the spinal cord. Difficulty in detecting abnormality at thoraco-lumbar junction on plain roentgenogram, and similarity of the symptoms to peripheral nerve disease often lead to a delay in diagnosis. The significance of dynamic myelography and delayed CT-myelography when dealing with such a lesion was discussed here. MRI is also a useful method for diagnosing a compressive lesion at the thoraco-lumbar junction. (author)

Visuo-locomotor control in persons with spinal cord injury in a manual or power wheelchair for direction change and obstacle circumvention.

Science.gov (United States)

Charette, Caroline; Routhier, François; McFadyen, Bradford J

2017-09-01

Many individuals, such as persons with spinal cord injury (SCI), rely on wheeled locomotion involving manual (MWC) or power (PWC) wheelchairs to navigate their environments. Yet, visuo-locomotor control underlying WC navigation in experienced users is not well understood. The objective of this study was to compare the visuo-locomotor control between MWC and PWC in individuals with SCI while changing direction and circumventing an obstacle. Participants with SCI using a MWC (n = 12, 38.5 ± 10.7 years) or a PWC (n = 10, 47.8 ± 8.6 years) were asked to maneuver their chair straight ahead, while changing direction 45° to the right, and while circumventing an obstacle to the right, all at self-selected speeds. Speed, minimal clearance, point of deviation, temporal body and WC coordination, relative timing of segment rotations and visual behavior were analyzed. There was no main effect of group for speed, clearance and point of deviation. During direction change, the head always led body and wheelchair reorientation while an "en bloc" strategy was used for circumventing obstacle for both groups. In straight-ahead locomotion, participants predominantly fixed their gaze on the end target. During direction change and obstacle circumvention, participants fixated more on the future path and the obstacle for both WC modes. Overall, specific gaze behavior depended on environmental demands. While MWC and PWC users adopt similar navigational strategies and visuo-locomotor coordination while changing direction and circumventing obstacle, there were some differences in the amount of head rotation that could be related to a counter-movement used more by PWC users.

Accuracy of Digital vs. Conventional Implant Impressions

Science.gov (United States)

Lee, Sang J.; Betensky, Rebecca A.; Gianneschi, Grace E.; Gallucci, German O.

2015-01-01

The accuracy of digital impressions greatly influences the clinical viability in implant restorations. The aim of this study is to compare the accuracy of gypsum models acquired from the conventional implant impression to digitally milled models created from direct digitalization by three-dimensional analysis. Thirty gypsum and 30 digitally milled models impressed directly from a reference model were prepared. The models were scanned by a laboratory scanner and 30 STL datasets from each group were imported to an inspection software. The datasets were aligned to the reference dataset by a repeated best fit algorithm and 10 specified contact locations of interest were measured in mean volumetric deviations. The areas were pooled by cusps, fossae, interproximal contacts, horizontal and vertical axes of implant position and angulation. The pooled areas were statistically analysed by comparing each group to the reference model to investigate the mean volumetric deviations accounting for accuracy and standard deviations for precision. Milled models from digital impressions had comparable accuracy to gypsum models from conventional impressions. However, differences in fossae and vertical displacement of the implant position from the gypsum and digitally milled models compared to the reference model, exhibited statistical significance (p<0.001, p=0.020 respectively). PMID:24720423

The spinal cord: a review of functional neuroanatomy.

Science.gov (United States)

Bican, Orhan; Minagar, Alireza; Pruitt, Amy A

2013-02-01

The spinal cord controls the voluntary muscles of the trunk and limbs and receives sensory input from these areas. It extends from the medulla oblongata to the lower border of the first lumbar vertebra. A basic knowledge of spinal cord anatomy is essential for interpretation of clinical signs and symptoms and for understanding of pathologic processes involving the spinal cord. In this article, anatomic structures are correlated with relevant clinical signs and symptoms and a step-wise approach to spinal cord diagnosis is outlined. Copyright © 2013 Elsevier Inc. All rights reserved.

Loss of Efficacy to Spinal Cord Stimulator Therapy: Clinical Evidence and Possible Causes.

Science.gov (United States)

Aiudi, Christopher M; Dunn, Roger Y; Burns, Sara M; Roth, Sarah A; Opalacz, Arissa; Zhang, Yi; Chen, Lucy; Mao, Jianren; Ahmed, Shihab U

2017-11-01

Although spinal cord stimulation (SCS) therapy has been shown to be efficacious in various pain conditions, the ability for SCS therapy to maintain long-term efficacy has been questioned. The purpose of this study was to investigate whether a loss of efficacy (LOE) phenomenon exists with SCS therapy and to investigate if this phenomenon is more apparent in any specific patient population. A retrospective, observation chart review was conducted to evaluate the patient response to SCS therapy over time. Massachusetts General Hospital, Boston, Massachusetts. Patients who received a SCS at the Massachusetts General Hospital, between January 1, 2002 and December 31, 2012, were invited to participate. A total of 62 patients were included in this study. Various models were created to analyze pain score changes over time using 2-tailed statistical analysis. Additionally, one-way ANOVA and Pearson's chi-square tests were used to determine if certain patient characteristics were associated with LOE. Compared to the visual analog scale (VAS) score at one month after device implantation, pain scores increased 1.95 points after 2 years (95% CI: 1.06 to 2.84, P = patient characteristic that helped predict LOE. However, patients who have significant baseline response to therapy may be more likely to experience LOE. Spinal cord stimulation, chronic pain, retrospective study, low frequency electrical stimulation, efficacy, chronic pain therapy.

Spinal cord injury drives chronic brain changes

Directory of Open Access Journals (Sweden)

Ignacio Jure

2017-01-01

Full Text Available Only a few studies have considered changes in brain structures other than sensory and motor cortex after spinal cord injury, although cognitive impairments have been reported in these patients. Spinal cord injury results in chronic brain neuroinflammation with consequent neurodegeneration and cognitive decline in rodents. Regarding the hippocampus, neurogenesis is reduced and reactive gliosis increased. These long-term abnormalities could explain behavioral impairments exhibited in humans patients suffering from spinal cord trauma.

Ion implantation

International Nuclear Information System (INIS)

Dearnaley, Geoffrey

1975-01-01