Science.gov

Sample records for technology ect implant

  1. Emulsion Chamber Technology Experiment (ECT)

    NASA Technical Reports Server (NTRS)

    Gregory, John C.; Takahashi, Yoshiyuki

    1996-01-01

    The experimental objective of Emulsion Chamber Technology (ECT) was to develop space-borne emulsion chamber technology so that cosmic rays and nuclear interactions may subsequently be studied at extremely high energies with long exposures in space. A small emulsion chamber was built and flown on flight STS-62 of the Columbia in March 1994. Analysis of the several hundred layers of radiation-sensitive material has shown excellent post-flight condition and suitability for cosmic ray physics analysis at much longer exposures. Temperature control of the stack was 20 +/-1 C throughout the active control period and no significant deviations of temperature or pressure in the chamber were observed over the entire mission operations period. The unfortunate flight attitude of the orbiter (almost 90% Earth viewing) prevented any significant number of heavy particles (Z greater than or equal to 10) reaching the stack and the inverted flow of shower particles in the calorimeter has not allowed evaluation of absolute primary cosmic ray-detection efficiency nor of the practical time limits of useful exposure of these calorimeters in space to the level of detail originally planned. Nevertheless, analysis of the observed backgrounds and quality of the processed photographic and plastic materials after the flight show that productive exposures of emulsion chambers are feasible in low orbit for periods of up to one year or longer. The engineering approaches taken in the ECT program were proven effective and no major environmental obstacles to prolonged flight are evident.

  2. Emerging Communication Technologies (ECT) Phase 4 Report

    NASA Technical Reports Server (NTRS)

    Bastin, Gary L.; Harris, William G.; Marin, Jose A.; Nelson, Richard A.

    2005-01-01

    The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Crew Exploration Vehicle (CEV), Advanced Range Technology Working Group (ARTWG), and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures on a 24/7 basis. ECT is a continuation of the Range Information System Management (RISM) task started in 2002. This is the fourth year of the project.

  3. Emerging Communication Technologies (ECT) Phase 3 Final Report

    NASA Technical Reports Server (NTRS)

    Bastin, Gary L.; Harris, William G.; Bates, Lakesha D.; Nelson, Richard A.

    2004-01-01

    The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Second Generation Reusable Launch Vehicle (2nd Gen RLV), Orbital Space Plane, Advanced Range Technology Working Group (ARTWG) and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures. ECT was a continuation of the Range Information System Management (RISM) task started in 2002. RISM identified the three advance communication technologies investigated under ECT. These were Wireless Ethernet (Wi-Fi), Free Space Optics (FSO), and Ultra Wideband (UWB). Due to the report s size, it has been broken into three volumes: 1) Main Report 2) Appendices 3) UWB.

  4. Emerging Communication Technologies (ECT) Phase 2 Report. Volume 2; Appendices

    NASA Technical Reports Server (NTRS)

    Bastin, Gary L.; Harris, William G.; Chiodini, Robert; Nelson, Richard A.; Huang, PoTien; Kruhm, David A.

    2003-01-01

    The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Second Generation Reusable Launch Vehicle (2nd Gen RLV), Orbital Space Plane, Advanced Range Technology Working Group (ARTWG) and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures. ECT was a continuation of the Range Information System Management (RISM) task started in 2002. RISM identified the three advance communication technologies investigated under ECT. These were Wireless Ethernet (Wi-Fi), Free Space Optics (FSO), and Ultra Wideband (UWB). Due to the report s size, it has been broken into three volumes: 1) Main Report 2) Appendices 3) UWB

  5. Emerging Communication Technologies (ECT) Phase 2 Report. Volume 3; Ultra Wideband (UWB) Technology

    NASA Technical Reports Server (NTRS)

    Bastin, Gary L.; Harris, William G.; Chiodini, Robert; Nelson, Richard A.; Huang, PoTien; Kruhm, David A.

    2003-01-01

    The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Second Generation Reusable Launch Vehicle (2nd Gen RLV), Orbital Space Plane, Advanced Range Technology Working Group (ARTWG) and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures. ECT was a continuation of the Range Information System Management (RISM) task started in 2002. RISM identified the three advance communication technologies investigated under ECT. These were Wireless Ethernet (Wi-Fi), Free Space Optics (FSO), and Ultra Wideband (UWB). Due to the report s size, it has been broken into three volumes: 1) Main Report 2) Appendices 3) UWB

  6. Emerging Communication Technologies (ECT) Phase 2 Report. Volume 1; Main Report

    NASA Technical Reports Server (NTRS)

    Bastin, Gary L.; Harris, William G.; Chiodini, Robert; Nelson, Richard A.; Huang, PoTien; Kruhm, David A.

    2003-01-01

    The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Second Generation Reusable Launch Vehicle (2nd Gen RLV), Orbital Space Plane, Advanced Range Technology Working Group (ARTWG) and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures. ECT was a continuation of the Range Information System Management (RISM) task started in 2002. RISM identified the three advance communication technologies investigated under ECT. These were Wireless Ethernet (Wi-Fi), Free Space Optics (FSO), and Ultra Wideband (UWB). Due to the report s size, it has been broken into three volumes: 1) Main Report 2) Appendices 3) UWB.

  7. Photonic technologies for visual implants

    NASA Astrophysics Data System (ADS)

    Buss, Ruediger; Praemassing, F.; Puettjer, D.; Stawski, N.; Jaeger, Dieter

    2003-02-01

    In this paper two applications of photonic technologies for visual implants in the field of medicine are presented. Both are technical systems working as vision aid for people suffering from blindness due to damages in their visual system. The first system is a retinal implant (RI), the second an intraocular vision aid (IoVA) for people with opaque cornea.

  8. Microsystems Technology for Retinal Implants

    NASA Astrophysics Data System (ADS)

    Weiland, James

    2005-03-01

    The retinal prosthesis is targeted to treat age-related macular degeneration, retinitis pigmentosa, and other outer retinal degenerations. Simulations of artificial vision have predicted that 600-1000 individual pixels will be needed if a retinal prosthesis is to restore function such as reading large print and face recognition. An implantable device with this many electrode contacts will require microsystems technology as part of its design. An implantable retinal prosthesis will consist of several subsystems including an electrode array and hermetic packaging. Microsystems and microtechnology approaches are being investigated as possible solutions for these design problems. Flexible polydimethylsiloxane (PDMS) substrate electrode arrays and silicon micromachined electrode arrays are under development. Inactive PDMS electrodes have been implanted in 3 dogs to assess mechanical biocompatibility. 3 dogs were followed for 6 months. The implanted was securely fastened to the retina with a single retinal tack. No post-operative complications were evident. The array remained within 100 microns of the retinal surface. Histological evaluation showed a well preserved retina underneath the electrode array. A silicon device with electrodes suspended on micromachined springs has been implanted in 4 dogs (2 acute implants, 2 chronic implants). The device, though large, could be inserted into the eye and positioned on the retina. Histological analysis of the retina from the spring electrode implants showed that spring mounted posts penetrated the retina, thus the device will be redesigned to reduce the strength of the springs. These initial implants will provide information for the designers to make the next generation silicon device. We conclude that microsystems technology has the potential to make possible a retinal prosthesis with 1000 individual contacts in close proximity to the retina.

  9. Advancing Binaural Cochlear Implant Technology.

    PubMed

    Dietz, Mathias; McAlpine, David

    2015-12-30

    This special issue contains a collection of 13 papers highlighting the collaborative research and engineering project entitled Advancing Binaural Cochlear Implant Technology-ABCIT-as well as research spin-offs from the project. In this introductory editorial, a brief history of the project is provided, alongside an overview of the studies.

  10. Using Aerospace Technology To Design Orthopedic Implants

    NASA Technical Reports Server (NTRS)

    Saravanos, D. A.; Mraz, P. J.; Davy, D. T.

    1996-01-01

    Technology originally developed to optimize designs of composite-material aerospace structural components used to develop method for optimizing designs of orthopedic implants. Development effort focused on designing knee implants, long-term goal to develop method for optimizing designs of orthopedic implants in general.

  11. Antimicrobial technology in orthopedic and spinal implants

    PubMed Central

    Eltorai, Adam EM; Haglin, Jack; Perera, Sudheesha; Brea, Bielinsky A; Ruttiman, Roy; Garcia, Dioscaris R; Born, Christopher T; Daniels, Alan H

    2016-01-01

    Infections can hinder orthopedic implant function and retention. Current implant-based antimicrobial strategies largely utilize coating-based approaches in order to reduce biofilm formation and bacterial adhesion. Several emerging antimicrobial technologies that integrate a multidisciplinary combination of drug delivery systems, material science, immunology, and polymer chemistry are in development and early clinical use. This review outlines orthopedic implant antimicrobial technology, its current applications and supporting evidence, and clinically promising future directions. PMID:27335811

  12. RFID technology for human implant devices

    NASA Astrophysics Data System (ADS)

    Aubert, Hervé

    2011-09-01

    This article presents an overview on Radio Frequency Identification (RFID) technology for human implants and investigates the technological feasibility of such implants for locating and tracking persons or for remotely controlling human biological functions. Published results on the miniaturization of implantable passive RFID devices are reported as well as a discussion on the choice of the transmission frequency in wireless communication between a passive RFID device implanted inside human body and an off-body interrogator. The two techniques (i.e., inductive coupling and electromagnetic coupling) currently used for wirelessly supplying power to and read data from a passive implantable RFID device are described and some documented biomedical and therapeutic applications of human RFID-implant devices are finally reported.

  13. Advancing Binaural Cochlear Implant Technology

    PubMed Central

    McAlpine, David

    2015-01-01

    This special issue contains a collection of 13 papers highlighting the collaborative research and engineering project entitled Advancing Binaural Cochlear Implant Technology—ABCIT—as well as research spin-offs from the project. In this introductory editorial, a brief history of the project is provided, alongside an overview of the studies. PMID:26721929

  14. Microsystem technologies for ophtalmological implants

    NASA Astrophysics Data System (ADS)

    Mokwa, Wilfried

    2003-01-01

    Due to the low power consumption CMOS electronics is ideal for the use in implanted systems. This paper presents two projects working on ophthalmological implants. Both systems are powered by an external RF-field. One system has been developed to measure the intraocular pressure continuously which is important for the therapy of glaucoma patients. The system consists of a micro coil and an integrated pressure transponder chip built into an artificial soft lens. A second example is a very complex system for epiretinal stimulation of the nerve cells of the retina. With such a system it might be possible to give blind people that are suffering from retinitis pigmentosa some visual contact to their surrounding.

  15. ECT and ethical psychiatry.

    PubMed

    Salzman, C

    1977-09-01

    The author discusses the right to receive ECT and describes voluntary and involuntary patients for whom the treatment seemed both ethical and humane. The right to refuse ECT must be respected in competent patients. However, problems arise when patients' decision-making ability is compromised by their illness. Informed consent questions include how much and what type of information patients should receive and how much those with disordered cognitive functioning can be expected to understand. The author believes that ECT should be fully voluntary whenever possible and that a court-appointed guardian should make such treatment decisions for incompetent patients.

  16. TOPICAL REVIEW: Microsystem technologies for implantable applications

    NASA Astrophysics Data System (ADS)

    Receveur, Rogier A. M.; Lindemans, Fred W.; de Rooij, Nicolaas F.

    2007-05-01

    Microsystem technologies (MST) have become the basis of a large industry. The advantages of MST compared to other technologies provide opportunities for application in implantable biomedical devices. This paper presents a general and broad literature review of MST for implantable applications focused on the technical domain. A classification scheme is introduced to order the examples, basic technological building blocks relevant for implantable applications are described and finally a case study on the role of microsystems for one clinical condition is presented. We observe that the microfabricated parts span a wide range for implantable applications in various clinical areas. There are 94 active and 67 commercial 'end items' out of a total of 142. End item refers to the total concept, of which the microsystem may only be a part. From the 105 active end items 18 (13% of total number of end items) are classified as products. From these 18 products, there are only two for chronic use. The number of active end items in clinical, animal and proto phase for chronic use is 17, 13 and 20, respectively. The average year of first publication of chronic end items that are still in the animal or clinical phase is 1994 (n = 7) and 1993 (n = 11), respectively. The major technology market combinations are sensors for cardiovascular, drug delivery for drug delivery and electrodes for neurology and ophthalmology. Together these form 51% of all end items. Pressure sensors form the majority of sensors and there is just one product (considered to be an implantable microsystem) in the neurological area. Micro-machined ceramic packages, glass sealed packages and polymer encapsulations are used. Glass to metal seals are used for feedthroughs. Interconnection techniques such as flip chip, wirebonding or conductive epoxy as used in the semiconductor packaging and assembly industry are also used for manufacturing of implantable devices. Coatings are polymers or metal. As an alternative to

  17. The sham ECT literature: implications for consent to ECT.

    PubMed

    Ross, Colin A

    2006-01-01

    The author reviewed the placebo-controlled literature on electroconvulsive therapy (ECT) for depression. No study demonstrated a significant difference between real and placebo (sham) ECT at 1 month posttreatment. Many studies failed to find a difference between real and sham ECT even during the period of treatment. Claims in textbooks and review articles that ECT is effective are not consistent with the published data. A large, properly designed study of real versus sham ECT should be undertaken. In the absence of such a study, consent forms for ECT should include statements that there is no controlled evidence demonstrating any benefit from ECT at 1 month posttreatment. Consent forms should also state that real ECT is only marginally more effective than placebo. PMID:16856307

  18. Implantable Micropump Technologies for Murine Intracochlear Infusions

    PubMed Central

    Johnson, D. G.; Waldron, M. J.; Frisina, R. D.; Borkholder, D. A.

    2011-01-01

    Due to the very small size of the mouse inner ear, 600 nL volume, developing effective, controlled infusion systems is quite challenging. Key technologies have been created to minimize both size and power for an implantable pump for murine intracochlear infusions. A method for coupling fine capillary tubing to microfluidic channels is presented which provides low volume, biocompatible interconnects withstanding pressures as high as 827 kPa (120 psi) and consuming less than 20 nL of volume exiting in-plane with the pump. Surface micromachined resistive bridges integrated into the flow channel for anemometry based flow rate measurement have been optimized for low power operation in the ultra-low flow rate regime. A process for creation of deformable diaphragms over pump chambers with simultaneous coating of the microfluidic channels has been developed allowing integration of a biocompatible fluid flow path. These advances represent enabling capabilities for a drug delivery system suitable for space constrained applications such as subcutaneous implantation in mice. PMID:21096713

  19. Evaluating the Feasibility of Using Remote Technology for Cochlear Implants

    ERIC Educational Resources Information Center

    Goehring, Jenny L.; Hughes, Michelle L.; Baudhuin, Jacquelyn L.

    2012-01-01

    The use of remote technology to provide cochlear implant services has gained popularity in recent years. This article contains a review of research evaluating the feasibility of remote service delivery for recipients of cochlear implants. To date, published studies have determined that speech-processor programming levels and other objective tests…

  20. New horizon for infection prevention technology and implantable device.

    PubMed

    Kondo, Yusuke; Ueda, Marehiko; Kobayashi, Yoshio; Schwab, Joerg O

    2016-08-01

    There has been a significant increase in the number of patients receiving cardiovascular implantable electronic devices (CIED) over the last two decades. CIED infection represents a serious complication after CIED implantation and is associated with significant morbidity and mortality. Recently, newly advanced technologies have offered attractive and suitable therapeutic alternatives. Notably, the leadless pacemaker and anti-bacterial envelope decrease the potential risk of CIED infection and the resulting mortality, when it does occur. A completely subcutaneous implantable cardioverter defibrillator is also an alternative to the transvenous implantable cardioverter defibrillator (ICD), as it does not require implantation of any transvenous or epicardial leads. Among the patients who require ICD removal and subsequent antibiotics secondary to infection, the wearable cardioverter defibrillator represents an alternative approach to inpatient monitoring for the prevention of sudden cardiac death. In this review paper, we aimed to introduce the advanced technologies and devices for prevention of CIED infection. PMID:27588153

  1. Research and Technology Transfer Ion Implantation Technology for Specialty Materials: Proceedings of a joint workshop

    NASA Astrophysics Data System (ADS)

    Reeber, Robert R.

    1991-02-01

    The ion implantation research and technology transfer workshop brought together a diverse group of academic, industrial, and government participants. Several key issues highlighted were: (1) a need exists for new technology transfer infrastructures between universities, research labs and industry; (2) ion implantation technology has promise for several Army and industry applications because of environmental concerns and technological benefits; (3) the U.S. ion implantation industry is primarily service oriented; and (4) the cost of ion implantation technology could be significantly reduced if larger scale production equipment was available for on-line processing. A need exists in the U.S. for mechanisms and funds to develop such equipment.

  2. Materials and technologies for soft implantable neuroprostheses

    NASA Astrophysics Data System (ADS)

    Lacour, Stéphanie P.; Courtine, Grégoire; Guck, Jochen

    2016-10-01

    Implantable neuroprostheses are engineered systems designed to restore or substitute function for individuals with neurological deficits or disabilities. These systems involve at least one uni- or bidirectional interface between a living neural tissue and a synthetic structure, through which information in the form of electrons, ions or photons flows. Despite a few notable exceptions, the clinical dissemination of implantable neuroprostheses remains limited, because many implants display inconsistent long-term stability and performance, and are ultimately rejected by the body. Intensive research is currently being conducted to untangle the complex interplay of failure mechanisms. In this Review, we emphasize the importance of minimizing the physical and mechanical mismatch between neural tissues and implantable interfaces. We explore possible materials solutions to design and manufacture neurointegrated prostheses, and outline their immense therapeutic potential.

  3. Ion sources for ion implantation technology (invited)

    SciTech Connect

    Sakai, Shigeki Hamamoto, Nariaki; Inouchi, Yutaka; Umisedo, Sei; Miyamoto, Naoki

    2014-02-15

    Ion sources for ion implantation are introduced. The technique is applied not only to large scale integration (LSI) devices but also to flat panel display. For LSI fabrication, ion source scheduled maintenance cycle is most important. For CMOS image sensor devices, metal contamination at implanted wafer is most important. On the other hand, to fabricate miniaturized devices, cluster ion implantation has been proposed to make shallow PN junction. While for power devices such as silicon carbide, aluminum ion is required. For doping processes of LCD fabrication, a large ion source is required. The extraction area is about 150 cm × 10 cm, and the beam uniformity is important as well as the total target beam current.

  4. Study on application of aerospace technology to improve surgical implants

    NASA Technical Reports Server (NTRS)

    Johnson, R. E.; Youngblood, J. L.

    1982-01-01

    The areas where aerospace technology could be used to improve the reliability and performance of metallic, orthopedic implants was assessed. Specifically, comparisons were made of material controls, design approaches, analytical methods and inspection approaches being used in the implant industry with hardware for the aerospace industries. Several areas for possible improvement were noted such as increased use of finite element stress analysis and fracture control programs on devices where the needs exist for maximum reliability and high structural performance.

  5. The evolution of cochlear implant technology and its clinical relevance

    PubMed Central

    Hainarosie, M; Zainea, V; Hainarosie, R

    2014-01-01

    The article presents a brief history of the development of the cochlear implant, from its beginnings to the present day. After a short description of the device, it describes the evolution of the technology for three of the top manufacturing companies, from the first model marketed, to the latest. It presents the technological advancements from one model to the next, taking into account the exterior design, processing capabilities and functionality. PMID:25870662

  6. The evolution of cochlear implant technology and its clinical relevance.

    PubMed

    Hainarosie, M; Zainea, V; Hainarosie, R

    2014-01-01

    The article presents a brief history of the development of the cochlear implant, from its beginnings to the present day. After a short description of the device, it describes the evolution of the technology for three of the top manufacturing companies, from the first model marketed, to the latest. It presents the technological advancements from one model to the next, taking into account the exterior design, processing capabilities and functionality.

  7. Optimal design of composite hip implants using NASA technology

    NASA Technical Reports Server (NTRS)

    Blake, T. A.; Saravanos, D. A.; Davy, D. T.; Waters, S. A.; Hopkins, D. A.

    1993-01-01

    Using an adaptation of NASA software, we have investigated the use of numerical optimization techniques for the shape and material optimization of fiber composite hip implants. The original NASA inhouse codes, were originally developed for the optimization of aerospace structures. The adapted code, which was called OPORIM, couples numerical optimization algorithms with finite element analysis and composite laminate theory to perform design optimization using both shape and material design variables. The external and internal geometry of the implant and the surrounding bone is described with quintic spline curves. This geometric representation is then used to create an equivalent 2-D finite element model of the structure. Using laminate theory and the 3-D geometric information, equivalent stiffnesses are generated for each element of the 2-D finite element model, so that the 3-D stiffness of the structure can be approximated. The geometric information to construct the model of the femur was obtained from a CT scan. A variety of test cases were examined, incorporating several implant constructions and design variable sets. Typically the code was able to produce optimized shape and/or material parameters which substantially reduced stress concentrations in the bone adjacent of the implant. The results indicate that this technology can provide meaningful insight into the design of fiber composite hip implants.

  8. ECT and Autism--Making the Connection.

    ERIC Educational Resources Information Center

    McCloskey-Dale, Susan R.

    This report describes using Environmental Communication Teaching (ECT) to assist students with autism spectrum disorder. The paper compares several key points of the ECT approach with other common intervention methods for students with autism and identifies the features of intervention programs or approaches that should be considered when planning…

  9. Adaptation of NASA technology for the optimum design of orthopedic knee implants.

    PubMed

    Saravanos, D A; Mraz, P J; Davy, D T; Hopkins, D A

    1991-03-01

    NASA technology originally developed for designing aircraft turbine-engine blades has been adapted and applied to orthopedic knee implants. This article describes a method for tailoring an implant for optimal interaction with the environment of the tibia. The implant components are designed to control stresses in the bone for minimizing bone degradation and preventing failures. Engineers expect the tailoring system to improve knee prosthesis design and allow customized implants for individual patients. PMID:10150099

  10. Advancing dental implant surface technology--from micron- to nanotopography.

    PubMed

    Mendonça, Gustavo; Mendonça, Daniela B S; Aragão, Francisco J L; Cooper, Lyndon F

    2008-10-01

    Current trends in clinical dental implant therapy include use of endosseous dental implant surfaces embellished with nanoscale topographies. The goal of this review is to consider the role of nanoscale topographic modification of titanium substrates for the purpose of improving osseointegration. Nanotechnology offers engineers and biologists new ways of interacting with relevant biological processes. Moreover, nanotechnology has provided means of understanding and achieving cell specific functions. The various techniques that can impart nanoscale topographic features to titanium endosseous implants are described. Existing data supporting the role of nanotopography suggest that critical steps in osseointegration can be modulated by nanoscale modification of the implant surface. Important distinctions between nanoscale and micron-scale modification of the implant surface are presently considered. The advantages and disadvantages of nanoscale modification of the dental implant surface are discussed. Finally, available data concerning the current dental implant surfaces that utilize nanotopography in clinical dentistry are described. Nanoscale modification of titanium endosseous implant surfaces can alter cellular and tissue responses that may benefit osseointegration and dental implant therapy.

  11. An Introduction to Cochlear Implant Technology, Activation, and Programming.

    ERIC Educational Resources Information Center

    Moore, Jan A.; Teagle, Holly F. B.

    2002-01-01

    This article provides information about the hardware components and speech-processing strategies of cochlear implant systems. The use of assistive listening devices with cochlear implants is also discussed. A brief description of surgical procedures and the initial activation of the device are also presented, along with programming considerations.…

  12. Science and technology of biocompatible thin films for implantable biomedical devices.

    SciTech Connect

    Li, W.; Kabius, B.; Auciello, O.; Materials Science Division

    2010-01-01

    This presentation focuses on reviewing research to develop two critical biocompatible film technologies to enable implantable biomedical devices, namely: (1) development of bioinert/biocompatible coatings for encapsulation of Si chips implantable in the human body (e.g., retinal prosthesis implantable in the human eye) - the coating involves a novel ultrananocrystalline diamond (UNCD) film or hybrid biocompatible oxide/UNCD layered films; and (2) development of biocompatible films with high-dielectric constant and microfabrication process to produce energy storage super-capacitors embedded in the microchip to achieve full miniaturization for implantation into the human body.

  13. Adaptation of NASA technology for the optimization of orthopedic knee implants

    NASA Technical Reports Server (NTRS)

    Saravanos, D. A.; Mraz, P. J.; Hopkins, D. A.

    1991-01-01

    The NASA technology originally developed for the optimization of composite structures (engine blades) is adapted and applied to the optimization of orthopedic knee implants. A method is developed enabling the tailoring of the implant for optimal interaction with the environment of the tibia. The shape of the implant components are optimized, such that the stresses in the bone are favorably controlled to minimize bone degradation and prevent failures. A pilot tailoring system is developed and the feasibility of the concept is elevated. The optimization system is expected to provide the means for improving knee prosthesis and individual implant tailoring for each patient.

  14. Computer-aided manufacturing technologies for guided implant placement.

    PubMed

    Neugebauer, Jörg; Stachulla, Gerhard; Ritter, Lutz; Dreiseidler, Timo; Mischkowski, Robert A; Keeve, Erwin; Zöller, Joachim E

    2010-01-01

    Implant treatment increasingly focuses on the reduction of treatment time and postoperative impairment. The improvement of 3D dental diagnosis by ConeBeam computed tomography allows detailed preparation for the surgical placement of dental implants under prosthetic considerations. While the first generation of implant planning software used high-contrast multislice computed tomography, software that has been specifically designed for ConeBeam computed tomography is now available. Implant placement can be performed using surgical guides or under the control of optical tracking systems. Surgical guides are more commonly used in private office owing to their availability. The accuracy for both techniques is clinically acceptable for achieving implant placement in critical anatomical indications. When using prefabricated superstructures and in flapless surgery, special abutments or an adjusted workflow are still necessary to compensate misfits of between 150 and 600 microm. The proposition to ensure proper implant placement by dentists with limited surgical experience through the use of surgical guides is unlikely to be successful, because there is also a specific learning curve for guided implant placement. Current and future development will continue to decrease the classical laboratory-technician work and will integrate the fabrication of superstructures with virtual treatment planning from the start.

  15. Optimizing implant placement and aesthetics: technology to the rescue!

    PubMed

    Kosinski, Timothy

    2009-08-01

    The goal for this patient was to create an aesthetic smile design using individual dental implants to reconstruct the edentulous spaces. Procera crowns aesthetically restored the separate and distinct teeth (Figures 18 and 19). The patient was thrilled with the final aesthetic result, and she was able to smile confidently again.

  16. A phone-assistive device based on Bluetooth technology for cochlear implant users.

    PubMed

    Qian, Haifeng; Loizou, Philipos C; Dorman, Michael F

    2003-09-01

    Hearing-impaired people, and particularly hearing-aid and cochlear-implant users, often have difficulty communicating over the telephone. The intelligibility of telephone speech is considerably lower than the intelligibility of face-to-face speech. This is partly because of lack of visual cues, limited telephone bandwidth, and background noise. In addition, cellphones may cause interference with the hearing aid or cochlear implant. To address these problems that hearing-impaired people experience with telephones, this paper proposes a wireless phone adapter that can be used to route the audio signal directly to the hearing aid or cochlear implant processor. This adapter is based on Bluetooth technology. The favorable features of this new wireless technology make the adapter superior to traditional assistive listening devices. A hardware prototype was built and software programs were written to implement the headset profile in the Bluetooth specification. Three cochlear implant users were tested with the proposed phone-adapter and reported good speech quality.

  17. Nanomaterials and synergistic low intensity direct current (LIDC) stimulation technology for orthopaedic implantable medical devices

    PubMed Central

    Samberg, Meghan E.; Cohen, Paul H.; Wysk, Richard A.; Monteiro-Riviere, Nancy A.

    2012-01-01

    Nanomaterials play a significant role in biomedical research and applications due to their unique biological, mechanical, and electrical properties. In recent years, they have been utilised to improve the functionality and reliability of a wide range of implantable medical devices ranging from well-established orthopaedic residual hardware devices (e.g. hip implants) that can repair defects in skeletal systems to emerging tissue engineering scaffolds that can repair or replace organ functions. This review summarizes the applications and efficacies of these nanomaterials that include synthetic or naturally occurring metals, polymers, ceramics, and composites in orthopaedic implants, the largest market segment of implantable medical devices. The importance of synergistic engineering techniques that can augment or enhance the performance of nanomaterial applications in orthopaedic implants is also discussed,, the focus being on a low intensity direct electric current (LIDC) stimulation technology to promote the long-term antibacterial efficacy of oligodynamic metal-based surfaces by ionization, while potentially accelerating tissue growth and osseointegration. While many nanomaterials have clearly demonstrated their ability to provide more effective implantable medical surfaces, further decisive investigations are necessary before they can translate into medically safe and commercially viable clinical applications. The paper concludes with a discussion about some of the critical impending issues with the application of nanomaterials-based technologies in implantable medical devices, and potential directions to address these. PMID:23335493

  18. Ion Implant Technology for Intermediate Band Solar Cells

    NASA Astrophysics Data System (ADS)

    Olea, Javier; Pastor, David; Luque, María Toledano; Mártil, Ignacio; Díaz, Germán González

    This chapter describes the creation of an Intermediate Band (IB) on single crystal silicon substrates by means of high-dose Ti implantation and subsequent Pulsed Laser Melting (PLM). The Ti concentration over the Mott limit is confirmed by Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS) measurements and the recovery of the crystallinity after annealing by means of Glancing Incidence X Ray Diffraction (GIXRD) and Transmission Electron Microscopy (TEM). Rutherford Backscattering Spectroscopy (RBS) measurements show that most of the atoms are located interstitially. Analysis of the sheet resistance and mobility measured using the van der Pauw geometry shows a temperature-dependent decoupling between the implanted layer and the substrate. This decoupling and the high laminated conductivity of the implanted layer could not be explained except if we assume that an IB has been formed in the semiconductor. A specific model for the bilayer electrical behaviour has been developed. The fitting of this model and also the simulation of the sheet resistance with the ATLAS code allow to determine that the IB energetic position is located around 0.36-0.38 eV below the conduction band. Carriers at the IB have a density very similar to the Ti concentration and behave as holes with mobilities as low as 0.4 cm2 Vs- 1.

  19. Technological, biological, and acoustical constraints to music perception in cochlear implant users.

    PubMed

    Limb, Charles J; Roy, Alexis T

    2014-02-01

    Despite advances in technology, the ability to perceive music remains limited for many cochlear implant users. This paper reviews the technological, biological, and acoustical constraints that make music an especially challenging stimulus for cochlear implant users, while highlighting recent research efforts to overcome these shortcomings. The limitations of cochlear implant devices, which have been optimized for speech comprehension, become evident when applied to music, particularly with regards to inadequate spectral, fine-temporal, and dynamic range representation. Beyond the impoverished information transmitted by the device itself, both peripheral and central auditory nervous system deficits are seen in the presence of sensorineural hearing loss, such as auditory nerve degeneration and abnormal auditory cortex activation. These technological and biological constraints to effective music perception are further compounded by the complexity of the acoustical features of music itself that require the perceptual integration of varying rhythmic, melodic, harmonic, and timbral elements of sound. Cochlear implant users not only have difficulty perceiving spectral components individually (leading to fundamental disruptions in perception of pitch, melody, and harmony) but also display deficits with higher perceptual integration tasks required for music perception, such as auditory stream segregation. Despite these current limitations, focused musical training programs, new assessment methods, and improvements in the representation and transmission of the complex acoustical features of music through technological innovation offer the potential for significant advancements in cochlear implant-mediated music perception.

  20. Surface characterization and biocompatibility of titanium alloys implanted with nitrogen by Hardion+ technology.

    PubMed

    Gordin, D M; Gloriant, T; Chane-Pane, V; Busardo, D; Mitran, V; Höche, D; Vasilescu, C; Drob, S I; Cimpean, A

    2012-12-01

    In this study, the new Hardion+ micro-implanter technology was used to modify surface properties of biomedical pure titanium (CP-Ti) and Ti-6Al-4V ELI alloy by implantation of nitrogen ions. This process is based on the use of an electron cyclotron resonance ion source to produce a multienergetic ion beam from multicharged ions. After implantation, surface analysis methods revealed the formation of titanium nitride (TiN) on the substrate surfaces. An increase in superficial hardness and a significant reduction of friction coefficient were observed for both materials when compared to non-implanted samples. Better corrosion resistance and a significant decrease in ion release rates were observed for N-implanted biomaterials due to the formation of the protective TiN layer on their surfaces. In vitro tests performed on human fetal osteoblasts indicated that the cytocompatibility of N-implanted CP-Ti and Ti-6Al-4V alloy was enhanced in comparison to that of the corresponding non treated samples. Consequently, Hardion+ implantation technique can provide titanium alloys with better qualities in terms of corrosion resistance, cell proliferation, adhesion and viability.

  1. Biofilm Disrupting Technology for Orthopedic Implants: What’s on the Horizon?

    PubMed Central

    Connaughton, Alexander; Childs, Abby; Dylewski, Stefan; Sabesan, Vani J.

    2014-01-01

    The use of orthopedic implants in joints has revolutionized the treatment of patients with many debilitating chronic musculoskeletal diseases such as osteoarthritis. However, the introduction of foreign material into the human body predisposes the body to infection. The treatment of these infections has become very complicated since the orthopedic implants serve as a surface for multiple species of bacteria to grow at a time into a resistant biofilm layer. This biofilm layer serves as a protectant for the bacterial colonies on the implant making them more resistant and difficult to eradicate when using standard antibiotic treatment. In some cases, the use of antibiotics alone has even made the bacteria more resistant to treatment. Thus, there has been surge in the creation of non-antibiotic anti-biofilm agents to help disrupt the biofilms on the orthopedic implants to help eliminate the infections. In this study, we discuss infections of orthopedic implants in the shoulder then we review the main categories of anti-biofilm agents that have been used for the treatment of infections on orthopedic implants. Then, we introduce some of the newer biofilm disrupting technology that has been studied in the past few years that may advance the treatment options for orthopedic implants in the future. PMID:25705632

  2. Science and technology of biocompatible thin films for implantable biomedical devices.

    PubMed

    Li, Wei; Kabius, Bernd; Auciello, Orlando

    2010-01-01

    This presentation focuses on reviewing research to develop two critical biocompatible film technologies to enable implantable biomedical devices, namely: 1) development of bioinert/biocompatible coatings for encapsulation of Si chips implantable in the human body (e.g., retinal prosthesis implantable in the human eye)-the coating involves a novel ultrananocrystalline diamond (UNCD) film or hybrid biocompatible oxide/UNCD layered films; and 2) development of biocompatible films with high-dielectric constant and microfabrication process to produce energy storage super-capacitors embedded in the microchip to achieve full miniaturization for implantation into the human bodynovel Al2O3/TiO2 nanolaminates exhibit abnormally high dielectric constant to enable super-capacitors with very high-capacitance.

  3. Regulatory science of new technology: tendency of medical professionals' interests on silicone breast implants.

    PubMed

    Nakazaki, Tomomichi; Ikeda, Koji; Iwasaki, Kiyotaka; Umezu, Mitsuo

    2016-09-01

    New technology related to artificial organs is most attractive for worldwide researchers. We believe they must contribute for the future patients against untreatable diseases. Regulatory science is a new science to establish 'social acceptance' of new technology into the clinical market as soon as possible. In the history of silicone breast implants, we could recognize risks many times; however, we missed such chances to prevent a subsequent crisis. We analyzed the trend of published literature related to silicone breast implants to review the medical professionals' interests on such risks. This trend showed, despite issues of a social acceptance of silicone breast implants in a few countries, other countries' medical professionals had no interest. Our hypothesis is 'medical professionals face the government and do not have contributed to re-establish the social acceptance of new technologies for patients'. Any technology does not have the complete evidence of safety, efficacy and quality, despite regulatory authorities' review and approval with clinical evidences. medical professionals need to conduct subsequently the epidemiological study, to take a meta-analysis periodically and to create/update the guidance for their patients under their professional ethics after the marketing of new technologies. We need to take seriously the 'lesson learned' from the history of silicone breast implants for all kind of new technologies existed in the present.

  4. Molecular dynamics study on splitting of hydrogen-implanted silicon in Smart-Cut® technology

    NASA Astrophysics Data System (ADS)

    Bing, Wang; Bin, Gu; Rongying, Pan; Sijia, Zhang; Jianhua, Shen

    2015-03-01

    Defect evolution in a single crystal silicon which is implanted with hydrogen atoms and then annealed is investigated in the present paper by means of molecular dynamics simulation. By introducing defect density based on statistical average, this work aims to quantitatively examine defect nucleation and growth at nanoscale during annealing in Smart-Cut® technology. Research focus is put on the effects of the implantation energy, hydrogen implantation dose and annealing temperature on defect density in the statistical region. It is found that most defects nucleate and grow at the annealing stage, and that defect density increases with the increase of the annealing temperature and the decrease of the hydrogen implantation dose. In addition, the enhancement and the impediment effects of stress field on defect density in the annealing process are discussed. Project supported by the National Natural Science Foundation of China (No. 11372261), the Excellent Young Scientists Supporting Project of Science and Technology Department of Sichuan Province (No. 2013JQ0030), the Supporting Project of Department of Education of Sichuan Province (No. 2014zd3132), the Opening Project of Key Laboratory of Testing Technology for Manufacturing Process, Southwest University of Science and Technology-Ministry of Education (No. 12zxzk02), the Fund of Doctoral Research of Southwest University of Science and Technology (No. 12zx7106), and the Postgraduate Innovation Fund Project of Southwest University of Science and Technology (No. 14ycxjj0121).

  5. Evolution and acceptability of medical applications of RFID implants among early users of technology.

    PubMed

    Smith, Alan D

    2007-01-01

    RFID as a wireless identification technology that may be combined with microchip implants have tremendous potential in today's market. Although these implants have their advantages and disadvantages, recent improvements how allowed for implants designed for humans. Focus was given to the use of RFID tags and its effects on technology and CRM through a case study on VeriChip, the only corporation to hold the rights and the patent to the implantable chip for humans, and an empirically based study on working professionals to measure perceptions by early adopters of such technology. Through hypotheses-testing procedures, it was found that although some resistance to accept microchip implants was found in several applications, especially among gender, it was totally expected that healthcare and medical record keeping activities would be universally treated in a positive light and the use of authorities (namely governmental agencies) would be equally treated in a negative light by both sexes. Future trends and recommendations are presented along with statistical results collected through personal interviews.

  6. Plasma source ion implantation technology for engineering surfaces of materials

    NASA Astrophysics Data System (ADS)

    Wilson, E. H.; Lawrence, D. F.; Sridharan, K.; Sandstrom, P. W.

    2001-07-01

    Plasma Source Ion Implantation* (PSII) is a non-line-of-sight technique for energetic ion surface modification of materials. At the University of Wisconsin there are presently three PSII systems two of which measure about 1 m3 and a third that measures 0.1 m3. Plasma generation is achieved in vacuum through filamentary, RF, DC-pulsed, or glow discharge. High voltage pulsing is achieved using a tetrode modulator that pulses at up to 60kV or by a solid-state pulser that can supply 20kV. Recently, a crossatron modulator capable of 40kV and 1kA peak anode current was built in-house. Surface properties of a wide range of materials have been beneficially modified using PSII in ion implantation, film deposition, energetic ion mixing, and sputtering modes. Industrial field testing of PSII-treated parts has yielded promising results but successful commercialization requires judicious selection of applications which effectively exploit the unique aspects of PSII as a surface modification tool.*J.R. Conrad U.S. Patent#4764394, 1988

  7. Biomedical interfaces: titanium surface technology for implants and cell carriers.

    PubMed

    Schuler, Martin; Trentin, Diana; Textor, Marcus; Tosatti, Samuele G P

    2006-12-01

    Titanium and its alloys have become key materials for biomedical applications, mainly owing to their compatibility with human tissues and their mechanical strength. Effects of surface topography on cell and tissue response have been investigated extensively in the past, while (bio)chemical surface modification and its combination with designed topographies have remained largely unexplored. The following report describes some of the strategies used or intended to modify titanium surfaces, based on biological principles, with a focus on ultrathin biomimetic adlayers. One of the visions behind such approaches is to achieve improved healing and integration responses after implantation for patients, especially for those suffering from deficiencies, for example, diabetes or osteoporosis, two diseases that have increased drastically in our society during the last century.

  8. Serum potassium changes with e.C.T.

    PubMed

    Shukla, G D; Srivastava, S L; Kaur, A; Varma, D D; Doshi, L D

    1982-04-01

    Serum potassium changes with direct E.C.T. and with modified E.C.T., given under three anaesthetic (thiopentone, diazepam and propanidid) and relaxant (suxamethonium) combinations were studied in 25 patients. Ten patients each, undergoing minor surgical procedures, acted as controls for these three combinations. Modified E.C.T. caused a rise in scram potassium, which, being highest at 3 minutes, was sustained well beyond 10 minutes. Direct E.C.T. caused maximum rise within one minute which, however, came down rapidly. The rise following modified E.C.T. was one and half times more compared to that occurring in controls given only drugs but not E.C.T., in all the three anaesthetic-relaxant combinations. The rise from pre-induction level was maximum following diazepam and minimum with propanidid, thiopentone falling in between. The rise from pre-relaxant level, on the other hand, was maximum with thiopentone and minimum with propanidid.

  9. Implantable sensor technology: measuring bone and joint biomechanics of daily life in vivo

    PubMed Central

    2013-01-01

    Stresses and strains are major factors influencing growth, remodeling and repair of musculoskeletal tissues. Therefore, knowledge of forces and deformation within bones and joints is critical to gain insight into the complex behavior of these tissues during development, aging, and response to injury and disease. Sensors have been used in vivo to measure strains in bone, intraarticular cartilage contact pressures, and forces in the spine, shoulder, hip, and knee. Implantable sensors have a high impact on several clinical applications, including fracture fixation, spine fixation, and joint arthroplasty. This review summarizes the developments in strain-measurement-based implantable sensor technology for musculoskeletal research. PMID:23369655

  10. ECT in dissociative identity disorder and comorbid depression.

    PubMed

    DeBattista, C; Solvason, H B; Spiegel, D

    1998-12-01

    Dissociative identity disorder (DID), previously named multiple personality disorder, is a diagnosis often complicated by comorbid major depression. We report on four cases of DID associated with severe self-destructive behavior and comorbid major depression treated with electroconvulsive therapy (ECT). In three of the patients, ECT appeared to be helpful in treating the comorbid depression without adversely affecting the DID. The potential risks of using ECT in patients with DID are reviewed.

  11. SEMICONDUCTOR DEVICES: Reducing the influence of STI on SONOS memory through optimizing added boron implantation technology

    NASA Astrophysics Data System (ADS)

    Yue, Xu; Feng, Yan; Zhiguo, Li; Fan, Yang; Yonggang, Wang; Jianguang, Chang

    2010-09-01

    The influence of shallow trench isolation (STI) on a 90 nm polysilicon-oxide-nitride-oxide-silicon structure non-volatile memory has been studied based on experiments. It has been found that the performance of edge memory cells adjacent to STI deteriorates remarkably. The compressive stress and boron segregation induced by STI are thought to be the main causes of this problem. In order to mitigate the STI impact, an added boron implantation in the STI region is developed as a new solution. Four kinds of boron implantation experiments have been implemented to evaluate the impact of STI on edge cells, respectively. The experimental results show that the performance of edge cells can be greatly improved through optimizing added boron implantation technology.

  12. Technology developments to initiate a next generation of cochlear implants.

    PubMed

    Volckaerts, B; Corless, A R; Mercanzini, A; Silmon, A M; Bertsch, A; Van Himbeeck, C; Wasikiewicz, J; Vanden Bulcke, M; Vadgama, P; Renaud, P

    2007-01-01

    In the framework of the EU-supported research project Healthy Aims, we developed a range of novel electrode arrays and related technologies for use in hearing prosthesis. This paper summarizes our ongoing research activities on alternative electrode manufacturing routes, functional electrode interfaces and smart intra-cochlear and intra-modiolus electrode arrays.

  13. Cryogenic ion implantation near amorphization threshold dose for halo/extension junction improvement in sub-30 nm device technologies

    SciTech Connect

    Park, Hugh; Todorov, Stan; Colombeau, Benjamin; Rodier, Dennis; Kouzminov, Dimitry; Zou Wei; Guo Baonian; Khasgiwale, Niranjan; Decker-Lucke, Kurt

    2012-11-06

    We report on junction advantages of cryogenic ion implantation with medium current implanters. We propose a methodical approach on maximizing cryogenic effects on junction characteristics near the amorphization threshold doses that are typically used for halo implants for sub-30 nm technologies. BF{sub 2}{sup +} implant at a dose of 8 Multiplication-Sign 10{sup 13}cm{sup -2} does not amorphize silicon at room temperature. When implanted at -100 Degree-Sign C, it forms a 30 - 35 nm thick amorphous layer. The cryogenic BF{sub 2}{sup +} implant significantly reduces the depth of the boron distribution, both as-implanted and after anneals, which improves short channel rolloff characteristics. It also creates a shallower n{sup +}-p junction by steepening profiles of arsenic that is subsequently implanted in the surface region. We demonstrate effects of implant sequences, germanium preamorphization, indium and carbon co-implants for extension/halo process integration. When applied to sequences such as Ge+As+C+In+BF{sub 2}{sup +}, the cryogenic implants at -100 Degree-Sign C enable removal of Ge preamorphization, and form more active n{sup +}-p junctions and steeper B and In halo profiles than sequences at room temperature.

  14. A low-frequency versatile wireless power transfer technology for biomedical implants.

    PubMed

    Jiang, Hao; Zhang, Junmin; Lan, Di; Chao; Liou, Shyshenq; Shahnasser, Hamid; Fechter, Richard; Hirose, Shinjiro; Harrison, Michael; Roy, Shuvo

    2013-08-01

    Implantable biomedical sensors and actuators are highly desired in modern medicine. In many cases, the implant's electrical power source profoundly determines its overall size and performance . The inductively coupled coil pair operating at the radio-frequency (RF) has been the primary method for wirelessly delivering electrical power to implants for the last three decades . Recent designs significantly improve the power delivery efficiency by optimizing the operating frequency, coil size and coil distance . However, RF radiation hazard and tissue absorption are the concerns in the RF wireless power transfer technology (RF-WPTT) , . Also, it requires an accurate impedance matching network that is sensitive to operating environments between the receiving coil and the load for efficient power delivery . In this paper, a novel low-frequency wireless power transfer technology (LF-WPTT) using rotating rare-earth permanent magnets is demonstrated. The LF-WPTT is able to deliver 2.967 W power at  ∼ 180 Hz to an 117.1 Ω resistor over 1 cm distance with 50% overall efficiency. Because of the low operating frequency, RF radiation hazard and tissue absorption are largely avoided, and the power delivery efficiency from the receiving coil to the load is independent of the operating environment. Also, there is little power loss observed in the LF-WPTT when the receiving coil is enclosed by non-magnetic implant-grade stainless steel. PMID:23893211

  15. Fabrication of an implant-supported overdenture using CAD/CAM technology: a clinical report.

    PubMed

    Rinke, Sven; Ziebolz, Dirk

    2013-02-01

    This case report describes a new method for the fabrication of implant-supported overdentures that are rigidly retained by custom tapered abutments milled from commercially pure titanium using CAD/CAM technology. The dentition of a 60-year-old woman was restored with six implants in the edentulous maxilla. An implant-supported overdenture retained by custom tapered abutments was fabricated using CAD/CAM technology. Screw-retained abutments were designed and milled with a taper of 6 degrees. The reinforcing metallic denture base with integrated secondary crowns, exactly fitting on the tapered abutments, was fabricated from the same data set. The secondary structures could be seated tensionfree on the six abutments, creating friction in the final position. No clinical complications were observed at the 12-month follow-up examination, and the patient remained satisfied with the function and esthetics of the restoration. This case demonstrates the practicality of a fully CAD/CAM fabrication of an implant-supported overdenture retained by friction only. Controlled clinical studies are needed to evaluate the long-term performance of this type of restoration.

  16. A low-frequency versatile wireless power transfer technology for biomedical implants.

    PubMed

    Jiang, Hao; Zhang, Junmin; Lan, Di; Chao; Liou, Shyshenq; Shahnasser, Hamid; Fechter, Richard; Hirose, Shinjiro; Harrison, Michael; Roy, Shuvo

    2013-08-01

    Implantable biomedical sensors and actuators are highly desired in modern medicine. In many cases, the implant's electrical power source profoundly determines its overall size and performance . The inductively coupled coil pair operating at the radio-frequency (RF) has been the primary method for wirelessly delivering electrical power to implants for the last three decades . Recent designs significantly improve the power delivery efficiency by optimizing the operating frequency, coil size and coil distance . However, RF radiation hazard and tissue absorption are the concerns in the RF wireless power transfer technology (RF-WPTT) , . Also, it requires an accurate impedance matching network that is sensitive to operating environments between the receiving coil and the load for efficient power delivery . In this paper, a novel low-frequency wireless power transfer technology (LF-WPTT) using rotating rare-earth permanent magnets is demonstrated. The LF-WPTT is able to deliver 2.967 W power at  ∼ 180 Hz to an 117.1 Ω resistor over 1 cm distance with 50% overall efficiency. Because of the low operating frequency, RF radiation hazard and tissue absorption are largely avoided, and the power delivery efficiency from the receiving coil to the load is independent of the operating environment. Also, there is little power loss observed in the LF-WPTT when the receiving coil is enclosed by non-magnetic implant-grade stainless steel.

  17. Complete oral rehabilitation with implants using CAD/CAM technology, stereolithography, and conoscopic holography.

    PubMed

    Bentz, Robert M; Balshi, Stephen F

    2012-02-01

    A 64-year-old totally edentulous female initially presented with ill-fitting removable prostheses. A comprehensive treatment plan with dental implants was accepted by the patient. Clinical and laboratory procedures were executed using various computer technologies including computed tomography, rapid prototyping, and optical scanning using conoscopic holography. A review of the patient's treatment and various modalities used are the focus of this patient report.

  18. Plasma-based ion implantation and deposition: A review of physics,technology, and applications

    SciTech Connect

    Pelletier, Jacques; Anders, Andre

    2005-05-16

    After pioneering work in the 1980s, plasma-based ion implantation (PBII) and plasma-based ion implantation and deposition (PBIID) can now be considered mature technologies for surface modification and thin film deposition. This review starts by looking at the historical development and recalling the basic ideas of PBII. Advantages and disadvantages are compared to conventional ion beam implantation and physical vapor deposition for PBII and PBIID, respectively, followed by a summary of the physics of sheath dynamics, plasma and pulse specifications, plasma diagnostics, and process modeling. The review moves on to technology considerations for plasma sources and process reactors. PBII surface modification and PBIID coatings are applied in a wide range of situations. They include the by-now traditional tribological applications of reducing wear and corrosion through the formation of hard, tough, smooth, low-friction and chemically inert phases and coatings, e.g. for engine components. PBII has become viable for the formation of shallow junctions and other applications in microelectronics. More recently, the rapidly growing field of biomaterial synthesis makes used of PBII&D to produce surgical implants, bio- and blood-compatible surfaces and coatings, etc. With limitations, also non-conducting materials such as plastic sheets can be treated. The major interest in PBII processing originates from its flexibility in ion energy (from a few eV up to about 100 keV), and the capability to efficiently treat, or deposit on, large areas, and (within limits) to process non-flat, three-dimensional workpieces, including forming and modifying metastable phases and nanostructures. We use the acronym PBII&D when referring to both implantation and deposition, while PBIID implies that deposition is part of the process.

  19. Bilateral ECT induces bilateral increases in regional cortical thickness.

    PubMed

    van Eijndhoven, P; Mulders, P; Kwekkeboom, L; van Oostrom, I; van Beek, M; Janzing, J; Schene, A; Tendolkar, I

    2016-01-01

    Electroconvulsive therapy (ECT) is the most effective treatment for patients suffering from severe or treatment-resistant major depressive disorder (MDD). Unfortunately its underlying neurobiological mechanisms are still unclear. One line of evidence indicates that the seizures produced by ECT induce or stimulate neuroplasticity effects. Although these seizures also affect the cortex, the effect of ECT on cortical thickness is not investigated until now. We acquired structural magnetic resonance imaging data in 19 treatment-resistant MDD patients before and after a bilateral ECT course, and 16 healthy controls at 2 time points, and compared changes in cortical thickness between the groups. Our results reveal that ECT induces significant, bilateral increases in cortical thickness, including the temporal pole, inferior and middle temporal cortex and the insula. The pattern of increased cortical thickness was predominant in regions that are associated with seizure onset in ECT. Post hoc analyses showed that the increase in thickness of the insular cortex was larger in responders than in non-responders, which may point to a specific relationship of this region with treatment effects of ECT. PMID:27552587

  20. Bilateral ECT induces bilateral increases in regional cortical thickness

    PubMed Central

    van Eijndhoven, P; Mulders, P; Kwekkeboom, L; van Oostrom, I; van Beek, M; Janzing, J; Schene, A; Tendolkar, I

    2016-01-01

    Electroconvulsive therapy (ECT) is the most effective treatment for patients suffering from severe or treatment-resistant major depressive disorder (MDD). Unfortunately its underlying neurobiological mechanisms are still unclear. One line of evidence indicates that the seizures produced by ECT induce or stimulate neuroplasticity effects. Although these seizures also affect the cortex, the effect of ECT on cortical thickness is not investigated until now. We acquired structural magnetic resonance imaging data in 19 treatment-resistant MDD patients before and after a bilateral ECT course, and 16 healthy controls at 2 time points, and compared changes in cortical thickness between the groups. Our results reveal that ECT induces significant, bilateral increases in cortical thickness, including the temporal pole, inferior and middle temporal cortex and the insula. The pattern of increased cortical thickness was predominant in regions that are associated with seizure onset in ECT. Post hoc analyses showed that the increase in thickness of the insular cortex was larger in responders than in non-responders, which may point to a specific relationship of this region with treatment effects of ECT. PMID:27552587

  1. Fast proximity algorithm for MAP ECT reconstruction

    NASA Astrophysics Data System (ADS)

    Li, Si; Krol, Andrzej; Shen, Lixin; Xu, Yuesheng

    2012-03-01

    We arrived at the fixed-point formulation of the total variation maximum a posteriori (MAP) regularized emission computed tomography (ECT) reconstruction problem and we proposed an iterative alternating scheme to numerically calculate the fixed point. We theoretically proved that our algorithm converges to unique solutions. Because the obtained algorithm exhibits slow convergence speed, we further developed the proximity algorithm in the transformed image space, i.e. the preconditioned proximity algorithm. We used the bias-noise curve method to select optimal regularization hyperparameters for both our algorithm and expectation maximization with total variation regularization (EM-TV). We showed in the numerical experiments that our proposed algorithms, with an appropriately selected preconditioner, outperformed conventional EM-TV algorithm in many critical aspects, such as comparatively very low noise and bias for Shepp-Logan phantom. This has major ramification for nuclear medicine because clinical implementation of our preconditioned fixed-point algorithms might result in very significant radiation dose reduction in the medical applications of emission tomography.

  2. Electroconvulsive therapy (ECT) in literature: Sylvia Plath's The Bell Jar.

    PubMed

    Kellner, Charles H

    2013-01-01

    Sylvia Plath's well-known novel, The Bell Jar, recounts her experience of a severe depressive episode. In the novel, the protagonist is treated with electroconvulsive therapy (ECT), as was Plath in life. The first ECT is given in the now-obsolete "unmodified" form, without general anesthesia. Later in the story, she receives ECT again, this time with full general anesthesia and muscle relaxation, as is the standard of care today. This chapter examines how the novelistic descriptions of the treatment compare with actual clinical practice.

  3. [Hearing implants].

    PubMed

    Stokroos, Robert J; George, Erwin L J

    2013-01-01

    In the Netherlands, more than 1.5 million people suffer from sensorineural hearing loss or deafness. However, fitting conventional hearing aids does not provide a solution for everyone. In recent decades, developments in medical technology have produced implantable and other devices that restore both sensorineural and conductive hearing losses. These hearing devices can be categorized into bone conductive devices, implantable middle ear prostheses, cochlear implants and auditory brainstem implants. Furthermore, new implants aimed at treating tinnitus and loss of vestibular function have recently been developed.

  4. Making it stick: the role of structural design in implantable technologies.

    PubMed

    Lee, Wontae; Leask, Richard L; Moraes, Christopher

    2015-11-01

    Designing technologies that work within the human body requires innovation at the interface of biology, engineering, and material sciences. The human body presents a surprisingly hostile environment towards technologies designed to improve health, and recent approaches to these problems have leveraged the links between material form and function to improve implantable systems. The use of physical structure has emerged as a key design parameter in developing these systems, and has recently been applied to make significant progress in the field. Here, we highlight recent studies that demonstrate the innovative use of structure in the design of technologies meant to operate within the human body, with a specific focus on improving their biointegration, delivery, and functionality. PMID:26446511

  5. Making it stick: the role of structural design in implantable technologies.

    PubMed

    Lee, Wontae; Leask, Richard L; Moraes, Christopher

    2015-11-01

    Designing technologies that work within the human body requires innovation at the interface of biology, engineering, and material sciences. The human body presents a surprisingly hostile environment towards technologies designed to improve health, and recent approaches to these problems have leveraged the links between material form and function to improve implantable systems. The use of physical structure has emerged as a key design parameter in developing these systems, and has recently been applied to make significant progress in the field. Here, we highlight recent studies that demonstrate the innovative use of structure in the design of technologies meant to operate within the human body, with a specific focus on improving their biointegration, delivery, and functionality.

  6. Ion beam technology applications study. [ion impact, implantation, and surface finishing

    NASA Technical Reports Server (NTRS)

    Sellen, J. M., Jr.; Zafran, S.; Komatsu, G. K.

    1978-01-01

    Specific perceptions and possible ion beam technology applications were obtained as a result of a literature search and contact interviews with various institutions and individuals which took place over a 5-month period. The use of broad beam electron bombardment ion sources is assessed for materials deposition, removal, and alteration. Special techniques examined include: (1) cleaning, cutting, and texturing for surface treatment; (2) crosslinking of polymers, stress relief in deposited layers, and the creation of defect states in crystalline material by ion impact; and (3) ion implantation during epitaxial growth and the deposition of neutral materials sputtered by the ion beam. The aspects, advantages, and disadvantages of ion beam technology and the competitive role of alternative technologies are discussed.

  7. Effectiveness of ECT combined with risperidone against aggression in schizophrenia.

    PubMed

    Hirose, S; Ashby, C R; Mills, M J

    2001-03-01

    Aggressive behavior in schizophrenic patients can often be problematic not only for the patients themselves, but for their families and others. This study examined the effect of electroconvulsive therapy (ECT) in combination with risperidone in an open trial in 10 male schizophrenic patients with significant aggressive behaviors. Patients were given bilateral ECT five times a week in combination with risperidone. The mean total number of times of ECT was 6.6 (range 5-9). The aggressive behavior in five of the six patients, who showed positive symptoms, was rapidly ameliorated within 12 days. The ECT/risperidone regimen also eliminated aggressive behavior in four patients showing no positive symptoms within 10 days. These treatment effects lasted for at least 6 months in 9 (of the 10) patients. The results suggest that ECT, combined with risperidone, produce a rapid and effective elimination of aggressive behaviors in schizophrenic patients. In addition, there was a resolution of aggression in four patients with no positive symptoms. This suggests that aggression in some schizophrenic patients develops as a primary symptom of schizophrenia and is not related to other positive symptoms of the disease or the patient's personality traits. PMID:11281510

  8. The use of CAD/CAM technology to fabricate a custom ceramic implant abutment: a clinical report.

    PubMed

    Bertolini, Martinna de Mendonça e; Kempen, Juan; Lourenço, Eduardo José Veras; Telles, Daniel de Moraes

    2014-05-01

    Well-placed dental implants are a prerequisite of functional and esthetically successful dental implant-supported crowns. The presence of soft tissue is essential for excellent esthetics because the dental implant or titanium abutment may become visible if the soft-tissue contour is not acceptable. This clinical report describes the use of a custom ceramic implant abutment designed with computer-aided design and computer-aided manufacturing (CAD/CAM) technology by milling a zirconia framework that was cemented extraorally to a prefabricated titanium abutment with a reduced diameter. This ceramic abutment has the strength and precise fit of a titanium interface and also the esthetic advantages of shaded custom-milled zirconia, with no visible metal. PMID:24433839

  9. The use of CAD/CAM technology to fabricate a custom ceramic implant abutment: a clinical report.

    PubMed

    Bertolini, Martinna de Mendonça e; Kempen, Juan; Lourenço, Eduardo José Veras; Telles, Daniel de Moraes

    2014-05-01

    Well-placed dental implants are a prerequisite of functional and esthetically successful dental implant-supported crowns. The presence of soft tissue is essential for excellent esthetics because the dental implant or titanium abutment may become visible if the soft-tissue contour is not acceptable. This clinical report describes the use of a custom ceramic implant abutment designed with computer-aided design and computer-aided manufacturing (CAD/CAM) technology by milling a zirconia framework that was cemented extraorally to a prefabricated titanium abutment with a reduced diameter. This ceramic abutment has the strength and precise fit of a titanium interface and also the esthetic advantages of shaded custom-milled zirconia, with no visible metal.

  10. Fabrication of the mandibular implant-supported fixed restoration using CAD/CAM technology: a clinical report.

    PubMed

    Reshad, Mamaly; Cascione, Domenico; Aalam, Alexandre Amir

    2009-11-01

    The mandibular implant-supported fixed restoration is an appropriate treatment choice for patients with inadequate bone volume in the posterior mandible. Computer-aided design/computer-aided manufacturing (CAD/CAM) technology has broadened the scope and application for this treatment option. A milled titanium bar retaining individual all-ceramic zirconium oxide crowns, with composite resin replicating gingival tissues, is recommended as an acceptable variation for this type of prosthesis. An alternative method for fabricating a mandibular implant-supported fixed restoration using CAD/CAM technology is described.

  11. Surgical planning and prosthesis construction using computer technology and medical imaging for immediate loading of implants in the pterygomaxillary region.

    PubMed

    Balshi, Stephen F; Wolfinger, Glenn J; Balshi, Thomas J

    2006-06-01

    This report describes a protocol that uses computerized tomography (CT), computer-aided design/computer-assisted manufacture (CAD/CAM) technology, and the Internet to plan placement of anterior and posterior dental implants and construct a precise surgical template and definitive prosthesis, which is connected at the time of implant placement. This procedure drastically reduces surgical treatment time and the recovery period. Patients with an edentulous arch had a denture with radiopaque markers constructed for CT scans of the appropriate jaw. The CT images, with acquisition slices of 0.5 mm, were transferred into a three-dimensional image-based program for planning and strategic placement of dental implants. After implants were virtually placed on the computer, the surgical treatment plan was sent to a manufacturing facility for construction of a surgical template and the prosthesis, Special surgical guide components were also manufactured for placement of implants in the pterygomaxillary region. The manufactured surgical components, surgical template, and definitive prosthesis were then delivered to the clinical site. Implant placement surgery was performed using the surgical template, without a flap, and the prosthesis was delivered, achieving immediate functional loading. Minor occlusal adjustments were made. The total surgical treatment time required was less than 60 minutes. Postoperative symptoms, such as pain, swelling, and inflammation, were minimal. Identification of the bone in relationship to the tooth position via three-dimensional CT prior to surgery allows precise placement of implants. CAD/CAM technology using the three-dimensional images allows for fabrication of the surgical guide and final prosthesis. This is a significant advancement in implant dentistry and prosthodontics.

  12. Implantable Microimagers

    PubMed Central

    Ng, David C.; Tokuda, Takashi; Shiosaka, Sadao; Tano, Yasuo; Ohta, Jun

    2008-01-01

    Implantable devices such as cardiac pacemakers, drug-delivery systems, and defibrillators have had a tremendous impact on the quality of live for many disabled people. To date, many devices have been developed for implantation into various parts of the human body. In this paper, we focus on devices implanted in the head. In particular, we describe the technologies necessary to create implantable microimagers. Design, fabrication, and implementation issues are discussed vis-à-vis two examples of implantable microimagers; the retinal prosthesis and in vivo neuro-microimager. Testing of these devices in animals verify the use of the microimagers in the implanted state. We believe that further advancement of these devices will lead to the development of a new method for medical and scientific applications.

  13. Study of millisecond laser annealing on ion implanted soi and application to scaled finfet technology

    NASA Astrophysics Data System (ADS)

    Michalak, Tyler J.

    The fabrication of metal-oxide-semiconductor field effect transistors (MOSFET) requires the engineering of low resistance, low leakage, and extremely precise p-n junctions. The introduction of finFET technology has introduced new challenges for traditional ion implantation and annealing techniques in junction design as the fin widths continue to decrease for improved short channel control. This work investigates the use of millisecond scanning laser annealing in the formation of n-type source/drain junctions in next generation MOSFET. We present a model to approximate the true thermal profile for a commercial laser annealing process which allows us to represent more precisely specific thermal steps using Technology Computer Aided Design (TCAD). Sheet resistance and Hall Effect measurements for blanket films are used to correlate dopant activation and mobility with the regrowth process during laser anneal. We show the onset of high conductivity associated with completion of solid phase epitaxial regrowth (SPER) in the films. The Lattice Kinetic Monte Carlo (LKMC) model shows excellent agreement with cross section transmission electron microscopy (TEM), correlating the increase of conductivity with completion of crystal regrowth, increased activation, and crystal quality at various temperatures. As scaled devices move into the non-planar geometries and possibly adopt silicon-on-insulator (SOI) substrates, the crystal regrowth and dopant activation of amorphizing implants becomes more complicated and doping methods must adapt accordingly. Following the concept of the more recently proposed hot ion implantation and the benefits of laser anneal, we investigate a possible process flow for a 10/14 nm node SOI finFET by utilizing process and device TCAD. Device simulation parameters for the 10/14 nm node device are taken from a calibrated model based on fabricated non-planar 40 nm gate length device finFET. The implications on device performance are considered for the

  14. Ironic Technology: Old Age and the implantable cardioverter defibrillator in US health care

    PubMed Central

    Kaufman, Sharon R.; Mueller, Paul S.; Ottenberg, Abigale L.; Koenig, Barbara A.

    2010-01-01

    We take the example of cardiac devices, specifically the implantable cardioverter defibrillator, or ICD, to explore the complex cultural role of technology in medicine today. We focus on persons age 80 and above, for whom ICD use is growing in the U.S. We highlight an ironic feature of this device. While it postpones death and ‘saves’ life by thwarting a lethal heart rhythm, it also prolongs living in a state of dying from heart failure. In that regard the ICD is simultaneously a technology of life extension and dying. We explore that irony among the oldest age group -- those whose considerations of medical interventions are framed by changing societal assumptions of what constitutes premature death, the appropriate time for death and medicine’s goals in an aging society. Background to the rapidly growing use of this device among the elderly is the ‘technological imperative’ in medicine, bolstered today by the value given to evidence-based studies. We show how evidence contributes to standards of care and to the expansion of Medicare reimbursement criteria. Together, those factors shape the ethical necessity of physicians offering and patients accepting the ICD in late life. Two ethnographic examples document the ways in which those factors are lived in treatment discussions and in expectations about death and longevity. PMID:21126815

  15. Semiconductor thin film transfer by wafer bonding and advanced ion implantation layer splitting technologies

    NASA Astrophysics Data System (ADS)

    Lee, Tien-Hsi

    Wafer bonding is an attractive technology for modern semiconductor and microelectronic industry due to its variability in allowing combination of materials. Initially, the bonding of wafers of the same material, such as silicon-silicon wafer bonding has been major interest. In the meantime, research interest has shifted to the bonding of dissimilar materials such as silicon to quartz or to sapphire. Thermal stress coming from the different expansion coefficients usually is a barrier to the success of dissimilar material bonding. Thermal stress may cause debonding, sliding, cracking, thermal misfit dislocations, or film wrinkle to impair the quality of the transferred layer. This dissertation presents several effective approaches to solve the thermal stress problem. These approaches concern bonding processes (low vacuum bonding and storage), thinning (advanced ion implantation layer splitting), and annealing processes (accumulative effect of blister generation) and are combined to design the best heat-treatment cycle. For this propose the concept of hot bonding is used in order to effectively minimize the thermal mismatch of dissimilar material bonding during the bonding and thinning procedures. During the initial bonding and bond strengthening phase, the difference in the temperature between bonding and annealing processes should be decreased as much as possible to avoid excessive thermal stresses. This concept can be realized either by increasing the bonding temperature or by decreasing the annealing temperature. A thinning technique has to employed that can thin the device wafer before debonding occurs due to the thermal stress generated either from the cooling-down process in the first case or by the annealing process itself in the late case. The ion implantation layer splitting method, also known as the Smart-cutsp°ler process, developed by Bruel at LEIT in France is a practical thinning technique which satisfies the above requirement. In the study, an

  16. In vitro and in vivo evaluation of novel implantation technology in hydrogel contact lenses for controlled drug delivery.

    PubMed

    Maulvi, Furqan A; Lakdawala, Dhara H; Shaikh, Anjum A; Desai, Ankita R; Choksi, Harsh H; Vaidya, Rutvi J; Ranch, Ketan M; Koli, Akshay R; Vyas, Bhavin A; Shah, Dinesh O

    2016-03-28

    Glaucoma is commonly treated using eye drops, which is highly inefficient due to rapid clearance (low residence time) from ocular surface. Contact lenses are ideally suited for controlled drug delivery to cornea, but incorporation of any drug loaded particulate system (formulation) affect the optical and physical property of contact lenses. The objective of the present work was to implant timolol maleate (TM) loaded ethyl cellulose nanoparticle-laden ring in hydrogel contact lenses that could provide controlled drug delivery at therapeutic rates without compromising critical lens properties. TM-implant lenses were developed, by dispersing TM encapsulated ethyl cellulose nanoparticles in acrylate hydrogel (fabricated as ring implant) and implanted the same in hydrogel contact lenses (sandwich system). The TM-ethyl cellulose nanoparticles were prepared by double emulsion method at different ratios of TM to ethyl cellulose. The X-ray diffraction studies revealed the transformation of TM to amorphous state. In vitro release kinetic data showed sustained drug release within the therapeutic window for 168h (NP 1:3 batch) with 150μg loading. Cytotoxicity and ocular irritation study demonstrated the safety of TM-implant contact lenses. In vivo pharmacokinetic studies in rabbit tear fluid showed significant increase in mean residence time (MRT) and area under curve (AUC), with TM-implant contact lenses in comparison to eye drop therapy. In vivo pharmacodynamic data in rabbit model showed sustained reduction in intra ocular pressure for 192h. The study demonstrated the promising potential of implantation technology to treat glaucoma using contact lenses, and could serve as a platform for other ocular diseases.

  17. Development of a Functional Biohybrid Implant Formed from Periodontal Tissue Utilizing Bioengineering Technology.

    PubMed

    Nakajima, Kei; Oshima, Masamitsu; Yamamoto, Naomi; Tanaka, Chie; Koitabashi, Ryosuke; Inoue, Takashi; Tsuji, Takashi

    2016-09-01

    Current osseointegrated dental implants have been widely used for the rehabilitation of tooth loss. Although dental implants are considered an available treatment in the paradigm shift from traditional dental therapies, such as fixed dental bridges and removable dentures, the fundamental problems must be overcome before their clinical use in young patients who are still undergoing jawbone growth. Here, we show a novel bioengineering method for a functional biohybrid implant that is combined with adult-derived periodontal tissue and attached with bone tissue as a substitute for cementum. This biohybrid implant was successfully engrafted using the bioengineered periodontal ligament, and it restored physiological function, such as orthodontic movement through bone remodeling and appropriate responsiveness to noxious stimuli. Thus, this study represents the functional biohybrid implant's potential for clinical use as a next-generation dental implant using adult-derived tissues.

  18. The ObjECTS: Framework for Integrated Assessment: Hybrid Modeling of Transportation

    SciTech Connect

    Kim, Son H.; Edmonds, James A.; Lurz, Joshua; Smith, Steven J.; Wise, Marshall A.

    2006-09-01

    Technology is a central issue for the global climate change problem, requiring analysis tools that can examine the impact of specific technologies with a long-term, global context. This paper describes the architecture of the ObjECTS-MiniCAM integrated assessment model, which implements a long-term, global model of energy, economy, agriculture, land-use, atmosphere, and climate change in a framework that allows the flexible incorporation of explicit technology detail. We describe the implementation of a ''bottom-up'' representation of the transportation sector as an illustration of this approach, in which the resulting hybrid model is fully integrated, internally consistent and theoretically compatible with the regional and global modeling framework. The analysis of the transportation sector presented here supports and clarifies the need for a comprehensive strategy promoting advanced vehicle technologies and an economy-wide carbon policy to cost-effectively reduce carbon emissions from the transportation sector in the long-term.

  19. The dynamic behavior of Ect2 in response to DNA damage

    PubMed Central

    He, Dan; Xiang, Jinnan; Li, Baojie; Liu, Huijuan

    2016-01-01

    Ect2 is a BRCT-containing guanidine exchange factor for Rho GTPases. It is essential for cytokinesis and is also involved in tumorigenesis. Since most BRCT-containing proteins are involved in DNA damage response and/or DNA repair, we tested whether Ect2 plays similar roles. We report that in primary mouse embryonic fibroblasts (MEFs), DNA damage quickly led to Ect2 relocalization to the chromatin and DNA damage foci-like structures. Ect2 knockdown did not affect foci localization of γH2AX, TopBP1, or Brca1, or activation of Atm, yet it impeded p53 Ser15 phosphorylation and activation, and resulted in defects in apoptosis and activation of S and G2/M checkpoints in response to DNA damage. These results suggest that Ect2 plays a role in DNA damage response. Interestingly, Ect2 is down-regulated at late stages of DNA damage response. Although p53 and E2F1 have been shown to regulate Ect2 transcription, DNA damage-induced Ect2 down-regulation occurred in p53−/− or Atm−/− MEFs and E2F1 knockdown cells. Instead, DNA damage-induced Ect2 down-regulation is mainly attributable to decreased protein stability. Like Ect2 knockdown, Ect2 destabilization may help the cell to recover from DNA damage response. These results suggest that Ect2 plays roles in multiple aspects of DNA damage response. PMID:27074761

  20. Successful use of right unilateral ECT for catatonia: a case series.

    PubMed

    Cristancho, Pilar; Jewkes, Delaina; Mon, Thetsu; Conway, Charles

    2014-03-01

    Catatonia is a neuropsychiatric syndrome involving motor signs in association with disorders of mood, behavior, or thought. Bitemporal electrode placement electroconvulsive therapy (ECT) is a proven effective treatment for catatonia, and this mode of ECT delivery is the preferred method of treatment in this condition. Studies in major depressive disorder have demonstrated that suprathreshold, nondominant (right) hemisphere, unilateral electrode placement ECT has fewer adverse effects, especially cognitive adverse effects, than bitemporal ECT. This case series describes the use of right unilateral (RUL) ECT in 5 patients with catatonia. Before ECT, all 5 patients in this series initially failed therapy with benzodiazepines and psychotropic medications. Each catatonic patient received a series of 8 to 12 RUL ECT in an every-other-day series. After ECT, 4 of the 5 patients had a full recovery from catatonia. One patient achieved only partial response to RUL ECT, and no additional benefit was obtained with bitemporal ECT. All patients in this case series tolerated RUL ECT without major adverse effects. This case series illustrates successful use of RUL ECT in patients with catatonia and adds to the early literature demonstrating its effective use in treating this complex condition.

  1. Plasma-based ion implantation: a valuable technology for the elaboration of innovative materials and nanostructured thin films

    NASA Astrophysics Data System (ADS)

    Vempaire, D.; Pelletier, J.; Lacoste, A.; Béchu, S.; Sirou, J.; Miraglia, S.; Fruchart, D.

    2005-05-01

    Plasma-based ion implantation (PBII), invented in 1987, can now be considered as a mature technology for thin film modification. After a brief recapitulation of the principle and physics of PBII, its advantages and disadvantages, as compared to conventional ion beam implantation, are listed and discussed. The elaboration of thin films and the modification of their functional properties by PBII have already been achieved in many fields, such as microelectronics (plasma doping/PLAD), biomaterials (surgical implants, bio- and blood-compatible materials), plastics (grafting, surface adhesion) and metallurgy (hard coatings, tribology), to name a few. The major advantages of PBII processing lie, on the one hand, in its flexibility in terms of ion implantation energy (from 0 to 100 keV) and operating conditions (plasma density, collisional or non-collisional ion sheath), and, on the other hand, in the easy transferrability of processes from the laboratory to industry. The possibility of modifying the composition and physical nature of the films, or of drastically changing their physical properties over several orders of magnitude makes this technology very attractive for the elaboration of innovative materials, including metastable materials, and the realization of micro- or nanostructures. A review of the state of the art in these domains is presented and illustrated through a few selected examples. The perspectives opened up by PBII processing, as well as its limitations, are discussed.

  2. Model-based estimation for dynamic cardiac studies using ECT

    SciTech Connect

    Chiao, P.C.; Rogers, W.L.; Clinthorne, N.H.; Fessler, J.A.; Hero, A.O. . Div. of Nuclear Medicine)

    1994-06-01

    In this paper, the authors develop a strategy for joint estimation of physiological parameters and myocardial boundaries using ECT (Emission Computed Tomography). The authors construct an observation model to relate parameters of interest to the projection data and to account for limited ECT system resolution and measurement noise. The authors then use a maximum likelihood (ML) estimator to jointly estimate all the parameters directly from the projection data without reconstruction of intermediate images. The authors also simulate myocardial perfusion studies based on a simplified heart model to evaluate the performance of the model-based joint ML estimator and compare this performance to the Cramer-Rao lower bound. Finally, model assumptions and potential uses of the joint estimation strategy are discussed.

  3. Rationale for the Use of CAD/CAM Technology in Implant Prosthodontics

    PubMed Central

    Abduo, Jaafar; Lyons, Karl

    2013-01-01

    Despite the predictable longevity of implant prosthesis, there is an ongoing interest to continue to improve implant prosthodontic treatment and outcomes. One of the developments is the application of computer-aided design and computer-aided manufacturing (CAD/CAM) to produce implant abutments and frameworks from metal or ceramic materials. The aim of this narrative review is to critically evaluate the rationale of CAD/CAM utilization for implant prosthodontics. To date, CAD/CAM allows simplified production of precise and durable implant components. The precision of fit has been proven in several laboratory experiments and has been attributed to the design of implants. Milling also facilitates component fabrication from durable and aesthetic materials. With further development, it is expected that the CAD/CAM protocol will be further simplified. Although compelling clinical evidence supporting the superiority of CAD/CAM implant restorations is still lacking, it is envisioned that CAD/CAM may become the main stream for implant component fabrication. PMID:23690778

  4. Cochlear implantation: a biomechanical prosthesis for hearing loss.

    PubMed

    Yawn, Robert; Hunter, Jacob B; Sweeney, Alex D; Bennett, Marc L

    2015-01-01

    Cochlear implants are a medical prosthesis used to treat sensorineural deafness, and one of the greatest advances in modern medicine. The following article is an overview of cochlear implant technology. The history of cochlear implantation and the development of modern implant technology will be discussed, as well as current surgical techniques. Research regarding expansion of candidacy, hearing preservation cochlear implantation, and implantation for unilateral deafness are described. Lastly, innovative technology is discussed, including the hybrid cochlear implant and the totally implantable cochlear implant.

  5. Fabricating a tooth- and implant-supported maxillary obturator for a patient after maxillectomy with computer-guided surgery and CAD/CAM technology: A clinical report.

    PubMed

    Noh, Kwantae; Pae, Ahran; Lee, Jung-Woo; Kwon, Yong-Dae

    2016-05-01

    An obturator prosthesis with insufficient retention and support may be improved with implant placement. However, implant surgery in patients after maxillary tumor resection can be complicated because of limited visibility and anatomic complexity. Therefore, computer-guided surgery can be advantageous even for experienced surgeons. In this clinical report, the use of computer-guided surgery is described for implant placement using a bone-supported surgical template for a patient with maxillary defects. The prosthetic procedure was facilitated and simplified by using computer-aided design/computer-aided manufacture (CAD/CAM) technology. Oral function and phonetics were restored using a tooth- and implant-supported obturator prosthesis. No clinical symptoms and no radiographic signs of significant bone loss around the implants were found at a 3-year follow-up. The treatment approach presented here can be a viable option for patients with insufficient remaining zygomatic bone after a hemimaxillectomy. PMID:26774316

  6. Role of EctR as transcriptional regulator of ectoine biosynthesis genes in Methylophaga thalassica.

    PubMed

    Mustakhimov, I I; Reshetnikov, A S; Fedorov, D N; Khmelenina, V N; Trotsenko, Y A

    2012-08-01

    In the halophilic aerobic methylotrophic bacterium Methylophaga thalassica, the genes encoding the enzymes for biosynthesis of the osmoprotectant ectoine were shown to be located in operon ectABC-ask. Transcription of the ect-operon was started from the two promoters homologous to the σ(70)-dependent promoter of Escherichia coli and regulated by protein EctR, whose encoding gene, ectR, is transcribed from three promoters. Genes homologous to ectR of methylotrophs were found in clusters of ectoine biosynthesis genes in some non-methylotrophic halophilic bacteria. EctR proteins of methylotrophic and heterotrophic halophiles belong to the MarR-family of transcriptional regulators but form a separate branch on the phylogenetic tree of the MarR proteins.

  7. Polymeric heart valves for surgical implantation, catheter-based technologies and heart assist devices.

    PubMed

    Bezuidenhout, Deon; Williams, David F; Zilla, Peter

    2015-01-01

    Efficient function and long-term durability without the need for anticoagulation, coupled with the ability to be accommodated in many different types of patient, are the principal requirements of replacement heart valves. Although the clinical use of valves appeared to have remained steady for several decades, the evolving demands for the elderly and frail patients typically encountered in the developed world, and the needs of much younger and poorer rheumatic heart disease patients in the developing world have now necessitated new paradigms for heart valve technologies and associated materials. This includes further consideration of durable elastomeric materials. The use of polymers to produce flexible leaflet valves that have the benefits of current commercial bioprosthetic and mechanical valves without any of their deficiencies has been held desirable since the mid 1950s. Much attention has been focused on thermoplastic polyurethanes in view of their generally good physico-chemical properties and versatility in processing, coupled with the improving biocompatibility and stability of recent formulations. Accelerated in vitro durability of between 600 and 1000 million cycles has been achieved using polycarbonate urethanes, and good resistance to degradation, calcification and thrombosis in vivo has been shown with some polysiloxane-based polyurethanes. Nevertheless, polymeric valves have remained relegated to use in temporary ventricular assist devices for bridging heart failure patients to transplantation. Some recent studies suggest that there is a greater degree of instability in thermoplastic materials than hitherto believed so that significant challenges remain in the search for the combination of durability and biocompatibility that would allow polymeric valves to become a clinical reality for surgical implantation. Perhaps more importantly, they could become candidates for use in situations where minimally invasive transcatheter procedures are used to

  8. Implantable Heart Aid

    NASA Technical Reports Server (NTRS)

    1984-01-01

    CPI's human-implantable automatic implantable defibrillator (AID) is a heart assist system, derived from NASA's space circuitry technology, that can prevent erratic heart action known as arrhythmias. Implanted AID, consisting of microcomputer power source and two electrodes for sensing heart activity, recognizes onset of ventricular fibrillation (VF) and delivers corrective electrical countershock to restore rhythmic heartbeat.

  9. Electronic Current Transducer (ECT) for high voltage dc lines

    NASA Astrophysics Data System (ADS)

    Houston, J. M.; Peters, P. H., Jr.; Summerayes, H. R., Jr.; Carlson, G. J.; Itani, A. M.

    1980-02-01

    The development of a bipolar electronic current transducer (ECT) for measuring the current in a high voltage dc (HVDC) power line at line potential is discussed. The design and construction of a free standing ECT for use on a 400 kV line having a nominal line current of 2000 A is described. Line current is measured by a 0.0001 ohm shunt whose voltage output is sampled by a 14 bit digital data link. The high voltage interface between line and ground is traversed by optical fibers which carry digital light signals as far as 300 m to a control room where the digital signal is converted back to an analog representation of the shunt voltage. Two redundant electronic and optical data links are used in the prototype. Power to operate digital and optical electronics and temperature controlling heaters at the line is supplied by a resistively and capacitively graded 10 stage cascade of ferrite core transformers located inside the hollow, SF6 filled, porcelain support insulator. The cascade is driven by a silicon controlled rectifier inverter which supplies about 100 W of power at 30 kHz.

  10. Transaction-neutral implanted data collection interface as EMR driver: a model for emerging distributed medical technologies.

    PubMed

    Lorence, Daniel; Sivaramakrishnan, Anusha; Richards, Michael

    2010-08-01

    Electronic Medical Record (EMR) and Electronic Health Record (EHR) adoption continues to lag across the US. Cost, inconsistent formats, and concerns about control of patient information are among the most common reasons for non-adoption in physician practice settings. The emergence of wearable and implanted mobile technologies, employed in distributed environments, promises a fundamentally different information infrastructure, which could serve to minimize existing adoption resistance. Proposed here is one technology model for overcoming adoption inconsistency and high organization-specific implementation costs, using seamless, patient controlled data collection. While the conceptual applications employed in this technology set are provided by way of illustration, they may also serve as a transformative model for emerging EMR/EHR requirements. PMID:20703915

  11. EEG DELTA BAND SPECTRAL POWER: DIFFERNECES BETWEEN UNILATERAL AND BILATERAL ECT SEIZURES

    PubMed Central

    Dutt, D.Narayana; Mahapatra, P.K.; Gangadhar, B.N.; Sadasivan, P.K.; Janakiramaiah, N.; Subbakrishna, D.K.; Rao, K.M. Jyoti

    1997-01-01

    EEG was recorded from right and left frontal leads during bilateral (n=11) and unilateral (n=l4) ECTs. The seizure EEG was analyzed using East Fourier ′Transform and the spectral power oj the Delta (1-4 Hz) band was computed. The spectral power on both sides was similar in the bilateral ECT. Unilateral ECT produced asymmetry in the early - (first 8 seconds after stimulus offset) and mid - (17-32 seconds after the stimulus offset) siezure phases; the spectral power was lower on the unstimulated hemisphere. Studies to elucidate the relevance of EEG delta band of the seizure to therapeutic potency of ECT are suggested. PMID:21584046

  12. Poly(ADP-ribosyl)ation is recognized by ECT2 during mitosis.

    PubMed

    Li, Mo; Bian, Chunjing; Yu, Xiaochun

    2014-01-01

    Poly(ADP-ribosyl)ation is an unique posttranslational modification and required for spindle assembly and function during mitosis. However, the molecular mechanism of poly(ADP-ribose) (PAR) in mitosis remains elusive. Here, we show the evidence that PAR is recognized by ECT2, a key guanine nucleotide exchange factor in mitosis. The BRCT domain of ECT2 directly binds to PAR both in vitro and in vivo. We further found that α-tubulin is PARylated during mitosis. PARylation of α-tubulin is recognized by ECT2 and recruits ECT2 to mitotic spindle for completing mitosis. Taken together, our study reveals a novel mechanism by which PAR regulates mitosis.

  13. Unilateral and bilateral ECT: a study of memory disturbance and relief from depression

    PubMed Central

    Cronin, D.; Bodley, P.; Potts, L.; Mather, Marcia D.; Gardner, R. K.; Tobin, Jean C.

    1970-01-01

    Fifty-one endogenous and reactive female depressives were given a course of either unilateral non-dominant, unilateral dominant, or bilateral ECT. Visual and verbal memory tests and confusion ratings were administered at frequent intervals during the treatment course. Pre-and post-treatment assessments of depression were made. Comparisons of the therapeutic effect of six and of eight ECTs were studied separately. One month after the last ECT the patients were again assessed on the memory and the depression tests. The results of the memory tests indicate that unilateral non-dominant ECT produced least memory disturbance (particularly of a verbal kind) and also less immediate confusion within 40 minutes of each ECT. This observation applies more to the reactive than the endogenous group. Comparisons of the depression tests reveal that unilateral non-dominant ECT is as effective in relieving depression as bilateral ECT, though progress may be less rapid. The observation holds true only for the reactive depressives. Endogenous depressives benefit more from bilateral ECT. Caution is advised against the administration of unilateral dominant ECT, since this group does not respond to treatment as well as the other two groups. Degree of improvement as a whole does not appear to be related to the degree of confusion experienced. The implications of these findings are discussed. PMID:5478954

  14. The Effect of Technology and Testing Environment on Speech Perception Using Telehealth with Cochlear Implant Recipients

    ERIC Educational Resources Information Center

    Goehring, Jenny L.; Hughes, Michelle L.; Baudhuin, Jacquelyn L.; Valente, Daniel L.; McCreery, Ryan W.; Diaz, Gina R.; Sanford, Todd; Harpster, Roger

    2012-01-01

    Purpose: In this study, the authors evaluated the effect of remote system and acoustic environment on speech perception via telehealth with cochlear implant recipients. Method: Speech perception was measured in quiet and in noise. Systems evaluated were Polycom visual concert (PVC) and a hybrid presentation system (HPS). Each system was evaluated…

  15. The use of laser technology (Er;Cr:YSGG) and stereolithography to aid in the placement of a subperiosteal implant: case study.

    PubMed

    Kusek, Edward R

    2009-01-01

    The use of laser technology has helped this clinician to provide treatment with less postoperative pain and increased healing. The subperiosteal implant is a modality that has been used for several decades, although its popularity has declined in favor of endosseous dental implants. In some instances, however, it remains the treatment of choice, specifically in the atrophic mandible (where placement of endosseous implants is not possible) or when placement would increase the chances of jaw fracture. This article reports the case of a patient rehabilitated using a simplified surgical protocol involving laser surgery and stereolithography.

  16. Engineering the heart: Evaluation of conductive nanomaterials for improving implant integration and cardiac function

    PubMed Central

    Zhou, Jin; Chen, Jun; Sun, Hongyu; Qiu, Xiaozhong; Mou, Yongchao; Liu, Zhiqiang; Zhao, Yuwei; Li, Xia; Han, Yao; Duan, Cuimi; Tang, Rongyu; Wang, Chunlan; Zhong, Wen; Liu, Jie; Luo, Ying; (Mengqiu) Xing, Malcolm; Wang, Changyong

    2014-01-01

    Recently, carbon nanotubes together with other types of conductive materials have been used to enhance the viability and function of cardiomyocytes in vitro. Here we demonstrated a paradigm to construct ECTs for cardiac repair using conductive nanomaterials. Single walled carbon nanotubes (SWNTs) were incorporated into gelatin hydrogel scaffolds to construct three-dimensional ECTs. We found that SWNTs could provide cellular microenvironment in vitro favorable for cardiac contraction and the expression of electrochemical associated proteins. Upon implantation into the infarct hearts in rats, ECTs structurally integrated with the host myocardium, with different types of cells observed to mutually invade into implants and host tissues. The functional measurements showed that SWNTs were essential to improve the performance of ECTs in inhibiting pathological deterioration of myocardium. This work suggested that conductive nanomaterials hold therapeutic potential in engineering cardiac tissues to repair myocardial infarction. PMID:24429673

  17. Engineering the heart: Evaluation of conductive nanomaterials for improving implant integration and cardiac function

    NASA Astrophysics Data System (ADS)

    Zhou, Jin; Chen, Jun; Sun, Hongyu; Qiu, Xiaozhong; Mou, Yongchao; Liu, Zhiqiang; Zhao, Yuwei; Li, Xia; Han, Yao; Duan, Cuimi; Tang, Rongyu; Wang, Chunlan; Zhong, Wen; Liu, Jie; Luo, Ying; (Mengqiu) Xing, Malcolm; Wang, Changyong

    2014-01-01

    Recently, carbon nanotubes together with other types of conductive materials have been used to enhance the viability and function of cardiomyocytes in vitro. Here we demonstrated a paradigm to construct ECTs for cardiac repair using conductive nanomaterials. Single walled carbon nanotubes (SWNTs) were incorporated into gelatin hydrogel scaffolds to construct three-dimensional ECTs. We found that SWNTs could provide cellular microenvironment in vitro favorable for cardiac contraction and the expression of electrochemical associated proteins. Upon implantation into the infarct hearts in rats, ECTs structurally integrated with the host myocardium, with different types of cells observed to mutually invade into implants and host tissues. The functional measurements showed that SWNTs were essential to improve the performance of ECTs in inhibiting pathological deterioration of myocardium. This work suggested that conductive nanomaterials hold therapeutic potential in engineering cardiac tissues to repair myocardial infarction.

  18. Preconditioned Alternating Projection Algorithms for Maximum a Posteriori ECT Reconstruction

    PubMed Central

    Krol, Andrzej; Li, Si; Shen, Lixin; Xu, Yuesheng

    2012-01-01

    We propose a preconditioned alternating projection algorithm (PAPA) for solving the maximum a posteriori (MAP) emission computed tomography (ECT) reconstruction problem. Specifically, we formulate the reconstruction problem as a constrained convex optimization problem with the total variation (TV) regularization. We then characterize the solution of the constrained convex optimization problem and show that it satisfies a system of fixed-point equations defined in terms of two proximity operators raised from the convex functions that define the TV-norm and the constrain involved in the problem. The characterization (of the solution) via the proximity operators that define two projection operators naturally leads to an alternating projection algorithm for finding the solution. For efficient numerical computation, we introduce to the alternating projection algorithm a preconditioning matrix (the EM-preconditioner) for the dense system matrix involved in the optimization problem. We prove theoretically convergence of the preconditioned alternating projection algorithm. In numerical experiments, performance of our algorithms, with an appropriately selected preconditioning matrix, is compared with performance of the conventional MAP expectation-maximization (MAP-EM) algorithm with TV regularizer (EM-TV) and that of the recently developed nested EM-TV algorithm for ECT reconstruction. Based on the numerical experiments performed in this work, we observe that the alternating projection algorithm with the EM-preconditioner outperforms significantly the EM-TV in all aspects including the convergence speed, the noise in the reconstructed images and the image quality. It also outperforms the nested EM-TV in the convergence speed while providing comparable image quality. PMID:23271835

  19. DIS[subscript 2]ECT: A Framework for Effective Inclusive Science Instruction

    ERIC Educational Resources Information Center

    Spaulding, Lucinda S.; Flannagan, Jenny Sue

    2012-01-01

    The purpose of this article is to provide special education and general education teachers a framework (DIS[subscript 2]ECT) for teaching science in inclusive settings. DIS2ECT stands for Design (Backwards); Individualization; Scaffolding and Strategies; Experiential learning; Cooperative Learning; and Teamwork. This framework was derived from our…

  20. European Credit Transfer and Accumulation System: An Alternative Way to Calculate the ECTS Grades

    ERIC Educational Resources Information Center

    Grosges, Thomas; Barchiesi, Dominique

    2007-01-01

    The European Credit Transfer and Accumulation System (ECTS) has been developed and instituted to facilitate student mobility and academic recognition. This paper presents, discusses, and illustrates the pertinence and the limitation of the current statistical distribution of the ECTS grades, and we propose an alternative way to calculate the ECTS…

  1. Supporting Open Access to European Academic Courses: The ASK-CDM-ECTS Tool

    ERIC Educational Resources Information Center

    Sampson, Demetrios G.; Zervas, Panagiotis

    2013-01-01

    Purpose: This paper aims to present and evaluate a web-based tool, namely ASK-CDM-ECTS, which facilitates authoring and publishing on the web descriptions of (open) academic courses in machine-readable format using an application profile of the Course Description Metadata (CDM) specification, namely CDM-ECTS. Design/methodology/approach: The paper…

  2. 7 CFR 985.31 - Research and development proj-ects.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Research and development proj-ects. 985.31 Section 985... Research § 985.31 Research and development proj-ects. The Committee, with the approval of the Secretary, may establish or provide for the establishment of production research, marketing research...

  3. Assessing the Moderating Effect of the End User in Consumer Behavior: The Acceptance of Technological Implants to Increase Innate Human Capacities.

    PubMed

    Pelegrín-Borondo, Jorge; Reinares-Lara, Eva; Olarte-Pascual, Cristina; Garcia-Sierra, Marta

    2016-01-01

    Today, technological implants are being developed to increase innate human capacities, such as memory or calculation speed, and to endow us with new ones, such as the remote control of machines. This study's aim was two-fold: first, to introduce a Cognitive-Affective-Normative (CAN) model of technology acceptance to explain the intention to use this technology in the field of consumer behavior; and second, to analyze the differences in the intention to use it based on whether the intended implant recipient is oneself or one's child (i.e., the moderating effect of the end user). A multi-group analysis was performed to compare the results between the two groups: implant "for me" (Group 1) and implant "for my child" (Group 2). The model largely explains the intention to use the insideable technology for the specified groups [variance explained (R (2)) of over 0.70 in both cases]. The most important variables were found to be "positive emotions" and (positive) "subjective norm." This underscores the need to broaden the range of factors considered to be decisive in technology acceptance to include variables related to consumers' emotions. Moreover, statistically significant differences were found between the "for me" and "for my child" models for "perceived ease of use (PEU)" and "subjective norm." These findings confirm the moderating effect of the end user on new insideable technology acceptance.

  4. Assessing the Moderating Effect of the End User in Consumer Behavior: The Acceptance of Technological Implants to Increase Innate Human Capacities.

    PubMed

    Pelegrín-Borondo, Jorge; Reinares-Lara, Eva; Olarte-Pascual, Cristina; Garcia-Sierra, Marta

    2016-01-01

    Today, technological implants are being developed to increase innate human capacities, such as memory or calculation speed, and to endow us with new ones, such as the remote control of machines. This study's aim was two-fold: first, to introduce a Cognitive-Affective-Normative (CAN) model of technology acceptance to explain the intention to use this technology in the field of consumer behavior; and second, to analyze the differences in the intention to use it based on whether the intended implant recipient is oneself or one's child (i.e., the moderating effect of the end user). A multi-group analysis was performed to compare the results between the two groups: implant "for me" (Group 1) and implant "for my child" (Group 2). The model largely explains the intention to use the insideable technology for the specified groups [variance explained (R (2)) of over 0.70 in both cases]. The most important variables were found to be "positive emotions" and (positive) "subjective norm." This underscores the need to broaden the range of factors considered to be decisive in technology acceptance to include variables related to consumers' emotions. Moreover, statistically significant differences were found between the "for me" and "for my child" models for "perceived ease of use (PEU)" and "subjective norm." These findings confirm the moderating effect of the end user on new insideable technology acceptance. PMID:26941662

  5. Assessing the Moderating Effect of the End User in Consumer Behavior: The Acceptance of Technological Implants to Increase Innate Human Capacities

    PubMed Central

    Pelegrín-Borondo, Jorge; Reinares-Lara, Eva; Olarte-Pascual, Cristina; Garcia-Sierra, Marta

    2016-01-01

    Today, technological implants are being developed to increase innate human capacities, such as memory or calculation speed, and to endow us with new ones, such as the remote control of machines. This study's aim was two-fold: first, to introduce a Cognitive-Affective-Normative (CAN) model of technology acceptance to explain the intention to use this technology in the field of consumer behavior; and second, to analyze the differences in the intention to use it based on whether the intended implant recipient is oneself or one's child (i.e., the moderating effect of the end user). A multi-group analysis was performed to compare the results between the two groups: implant “for me” (Group 1) and implant “for my child” (Group 2). The model largely explains the intention to use the insideable technology for the specified groups [variance explained (R2) of over 0.70 in both cases]. The most important variables were found to be “positive emotions” and (positive) “subjective norm.” This underscores the need to broaden the range of factors considered to be decisive in technology acceptance to include variables related to consumers' emotions. Moreover, statistically significant differences were found between the “for me” and “for my child” models for “perceived ease of use (PEU)” and “subjective norm.” These findings confirm the moderating effect of the end user on new insideable technology acceptance. PMID:26941662

  6. Implantable technology for long-term delivery of nalmefene for treatment of alcoholism.

    PubMed

    Costantini, Lauren C; Kleppner, Sofie R; McDonough, Joseph; Azar, Marc R; Patel, Raj

    2004-09-28

    Pharmacotherapy treatment for alcoholism is limited by poor compliance, adverse effects, and fluctuating drug levels after bolus administration. A long-term delivery system would improve upon these limitations. The current study describes the characterization of a sustained release implant containing nalmefene, an opioid antagonist, for treatment of alcoholism. Nalmefene was blended with ethylene vinyl acetate (EVA), extruded into 2.8 mm x 27 mm rods, and coated with EVA to optimize release. In vitro release was determined by HPLC, and in vivo release characteristics after subcutaneous implantation into rats were determined by LC-MS/MS analyses. Extrusion produced rods containing 80.09 +/- 6.0 mg nalmefene. In vitro release was high from the uncoated rods, and they were depleted of drug fairly quickly; however EVA coatings maintained release over longer periods. The 25 wt.% coated rods provided in vitro release of 0.36 mg/day/rod, and in vivo release of 0.29 mg/day/rod over 6 months, and showed dose-dependent nalmefene plasma concentrations (one rod: 3.33 +/- 0.56 ng/ml, three rods: 10.19 +/- 2.31 ng/ml). After explantation, nalmefene plasma concentrations were undetectable by 6 h. A sustained release nalmefene rod provides 6 months of drug with no adverse effects.

  7. A Generic Method for Distribution and Transfer of ECTS and Other Norm-Referenced Grades within Student Cohorts

    ERIC Educational Resources Information Center

    Warfvinge, Per

    2008-01-01

    The ECTS grade transfer scale is an interface grade scale to help European universities, students and employers to understand the level of student achievement. Hence, the ECTS scale can be seen as an interface, transforming local scales to a common system where A-E denote passing grades. By definition, ECTS should distribute the passing students…

  8. The combination of digital surface scanners and cone beam computed tomography technology for guided implant surgery using 3Shape implant studio software: a case history report.

    PubMed

    Lanis, Alejandro; Álvarez Del Canto, Orlando

    2015-01-01

    The incorporation of virtual engineering into dentistry and the digitization of information are providing new perspectives and innovative alternatives for dental treatment modalities. The use of digital surface scanners with surgical planning software allows for the combination of the radiographic, prosthetic, surgical, and laboratory fields under a common virtual scenario, permitting complete digital treatment planning. In this article, the authors present a clinical case in which a guided implant surgery was performed based on a complete digital surgical plan combining the information from a cone beam computed tomography scan and the virtual simulation obtained from the 3Shape TRIOS intraoral surface scanner. The information was imported to and combined in the 3Shape Implant Studio software for guided implant surgery planning. A surgical guide was obtained by a 3D printer, and the surgical procedure was done using the Biohorizons Guided Surgery Kit and its protocol. PMID:25822304

  9. The combination of digital surface scanners and cone beam computed tomography technology for guided implant surgery using 3Shape implant studio software: a case history report.

    PubMed

    Lanis, Alejandro; Álvarez Del Canto, Orlando

    2015-01-01

    The incorporation of virtual engineering into dentistry and the digitization of information are providing new perspectives and innovative alternatives for dental treatment modalities. The use of digital surface scanners with surgical planning software allows for the combination of the radiographic, prosthetic, surgical, and laboratory fields under a common virtual scenario, permitting complete digital treatment planning. In this article, the authors present a clinical case in which a guided implant surgery was performed based on a complete digital surgical plan combining the information from a cone beam computed tomography scan and the virtual simulation obtained from the 3Shape TRIOS intraoral surface scanner. The information was imported to and combined in the 3Shape Implant Studio software for guided implant surgery planning. A surgical guide was obtained by a 3D printer, and the surgical procedure was done using the Biohorizons Guided Surgery Kit and its protocol.

  10. The Incidence and Predictors of Headache and Myalgia in Patients After Electroconvulsive Therapy (ECT)

    PubMed Central

    Haghighi, Mohammad; Sedighinejad, Abbas; Naderi Nabi, Bahram; Emiralavi, Cyrus; Biazar, Gelareh; Mirmozaffari, Kaveh; Zahedan, Cyrus; Jafari, Mehdi

    2016-01-01

    Background: Electroconvulsive therapy (ECT) is a safe and effective mode of therapy for a wide variety of psychiatric disorders. However, it is associated with some disturbing side effects, such as nausea and vomiting, dental and tongue injury, confusion, dizziness, headache, and myalgia. Objectives: The present study focused on the evaluation of myalgia and headache and their predictors after ECT. Patients and Methods: A prospective analytical descriptive study was conducted from October 2014 to January 2015, in an academic hospital in northern Iran. Before sampling, the study was approved by the ethics committee of Guilan University of Medical Sciences. 621 patients with psychiatric disorders who were referred to Shafa hospital enrolled in the study. They were evaluated based on a verbal rating scale (4 point scales) 6 hours after ECT, regarding headache and myalgia side effects. Results: 6 hours after ECT, 126 patients (21.9%) reported headaches, and 56 patients (9%) reported myalgia. The presence of headache or myalgia 6 hours after ECT was not correlated to the duration of convulsion, treatment sessions, sex, or age. But myalgia at 2 hours after treatment was correlated with sex (0.04). Sex, age, duration of seizure, and treatment sessions were not predictors of headache and myalgia 6 hours after ECT (log regression, enter mode). The intensity and frequency of headaches decreased during 6 hours after ECT (P = 0.0001 and P = 0.0001, respectively), and myalgia frequency decreased (P = 0.062) but the intensity increased (P = 0.87). Conclusions: The results of the present study demonstrate that headache after ECT procedures was more common than myalgia, but it was mild, tolerable, and decreased within 6 hours of the treatment. It is also notable that we did not found any predictors for post-ECT headache and myalgia. PMID:27761416

  11. Facial implants.

    PubMed

    Arcuri, M R; Rubenstein, J T

    1998-01-01

    The application of endosseous dental implants for the retention and stabilization of extraoral prostheses and hearing aids has been shown to be effective functionally and aesthetically. Implants have reduced the need for adhesive use, simplifying cleaning procedures and thus extending the life of the prosthesis. Implant-retained prostheses have provided patients the opportunity to participate in routine activities such as work, shopping, swimming, and jogging with less fear of losing their prosthesis. The implants' impact on patients has resulted in their ability to function in society with confidence that their defects will be less noticeable and their ability to respond to the environment enhanced. The culmination of these effects have without doubt improved the overall quality of life for patients. As with any new technology, its application will encounter unanticipated problems and some limitations in use. As the art and science of this technique evolve, however, it is anticipated that it will result in the ability to provide improved health care for patients.

  12. Miniature low-power inertial sensors: promising technology for implantable motion capture systems.

    PubMed

    Lambrecht, Joris M; Kirsch, Robert F

    2014-11-01

    Inertial and magnetic sensors are valuable for untethered, self-contained human movement analysis. Very recently, complete integration of inertial sensors, magnetic sensors, and processing into single packages, has resulted in miniature, low power devices that could feasibly be employed in an implantable motion capture system. We developed a wearable sensor system based on a commercially available system-in-package inertial and magnetic sensor. We characterized the accuracy of the system in measuring 3-D orientation-with and without magnetometer-based heading compensation-relative to a research grade optical motion capture system. The root mean square error was less than 4° in dynamic and static conditions about all axes. Using four sensors, recording from seven degrees-of-freedom of the upper limb (shoulder, elbow, wrist) was demonstrated in one subject during reaching motions. Very high correlation and low error was found across all joints relative to the optical motion capture system. Findings were similar to previous publications using inertial sensors, but at a fraction of the power consumption and size of the sensors. Such ultra-small, low power sensors provide exciting new avenues for movement monitoring for various movement disorders, movement-based command interfaces for assistive devices, and implementation of kinematic feedback systems for assistive interventions like functional electrical stimulation.

  13. Emergency ECT in an incapacitated, medically compromised patient with Huntington's disease.

    PubMed

    Magid, Michelle; Trevino, Kenneth; Reid, William H; Jalalat, Sheila; Husain, Mustafa M; Kahn, David A

    2014-11-01

    Electroconvulsive therapy (ECT) is infrequently considered an "emergency" medical procedure; however, there are certain conditions in which there is considerable urgency to initiate ECT. For example, prompt administration of ECT to treat neuroleptic malignant syndrome and malignant catatonia is necessary to improve a patient's overall prognosis and potentially save the patient's life. In this case, a 57-year-old woman with Huntington's disease was admitted to our medical intensive care unit for failure to thrive due to severe psychotic symptoms. Prior to her admission, the patient had become increasingly psychotic and agitated, resulting in her refusal and/or inability to eat. Efforts to treat her severe psychiatric and behavioral symptoms with various psychopharmacological strategies were largely unsuccessful. As the patient's physical health continued to decline, with loss of approximately 35 pounds over 2 months, her family began making arrangements to transfer her to a hospice facility. The day before she was to be transferred, the psychiatry consultation-liaison service recommended ECT. Unfortunately, this recommendation was complicated because the patient was unable to provide consent. This case report describes the legal and administrative process used to ethically and legally administer ECT without consent from the patient or a court-appointed guardian in order to treat a life-threatening condition. To the best of our knowledge, this report documents the first time ECT has been granted "medical emergency" status in Texas.

  14. Cochlear Implants.

    ERIC Educational Resources Information Center

    Clark, Catherine; Scott, Larry

    This brochure explains what a cochlear implant is, lists the types of individuals with deafness who may be helped by a cochlear implant, describes the process of evaluating people for cochlear implants, discusses the surgical process for implanting the aid, traces the path of sound through the cochlear implant to the brain, notes the costs of…

  15. Materials processing towards development of rapid prototyping technology for manufacturing biomedical implants

    NASA Astrophysics Data System (ADS)

    Pekin, Senol

    2000-10-01

    Materials processing towards development of fused deposition of materials (FDM) method for manufacturing biomedical implants has been studied experimentally. Main processing steps consisted of thermoplastic binder development in the ethylene vinyl acetate (EVA)-microcrystalline wax system, feedstock extrusion, characterization and optimization of binder degradation, and sintering of calcium deficient hydroxyapatite. Differential scanning calorimetry (DSC) revealed that the melting index (MI) of the copolymer affects the temperature location of the solidification exotherm, whereas the effect on the temperature location of the melting endotherm was negligible. Nonisothermal measurement of viscosity of different blends as a function of VA content of the EVA component revealed that the microcrystalline wax is compatible with 25--14% VA-containing EVA grades. Further DSC analysis revealed that co-crystallization leads to compatible EVA-microcrystalline wax blends. A typical binder formulation that was developed in the present work has a viscosity of about 700 cP at 140°C, a compressive yield strength of 6 MPa and an elastic modulus of about 600 MPa, and contained 15--20% EVA and 80--85% microcrystalline wax. Various filaments with a nominal diameter of 1.8 mm were extruded by using such a binder, and calcium pyro-phosphate powder that had a distribution modulus of about 0.37. Measurement of physical dimensions of the filament revealed that fluid state can be achieved in the filaments. Simultaneous thermal analysis of degradation characteristics of the typical binder formulations revealed that degradation sequence is oxidation of the hydrocarbons, evaporation of the hydrocarbons, degradation of the vinyl acetate, and degradation of the ethylene chain. A rate controlled binder removal system was developed and used in order to optimize the binder removal schedule. Sintering of gel-cast calcium hydroxyapatite was studied by means of thermal analysis, XRD, mechanical

  16. Income and Pollutant Emissions in the ObjECTS MiniCAM Model

    SciTech Connect

    Smith, Steven J.

    2005-01-03

    This paper examines the implications of the relationship between income and pollutant emission controls as parameterized in the ObjECTS MiniCAM integrated assessment model. Future scenarios for energy-related emissions of nitrous oxide (NOx) and sulfur dioxide (SO2) are presented along with the methodology used to parameterize this relationship. We use a “pseudo-Kuznets” approach where the level of emission control is assumed to vary with per-capita income. No explicit assumption is, therefore, made about the relationship between income and emissions — emissions are the result of driving forces, such as economic activity level, and energy combustion technology in addition to emission controls. Emission projections depend both on the assumptions for when emissions controls are implemented and the stringency of those controls. We suggest that historical analysis of the relationship between income and emission controls might be particularly useful in informing the selection of parameters that control when emission controls are implemented. Historical analysis is likely to be less helpful in informing the selection of parameters for the future levels of control, however, particularly at future times when parameter values are well outside the range of historical experience.

  17. Dental Implants

    MedlinePlus

    ... Procedures Dental Implants Dentures Direct Bonding Implants versus Bridges Orthodontics and Aligners Periodontal Plastic Surgery Porcelain Crowns Porcelain Fixed Bridges Porcelain Veneers Repairing Chipped Teeth Teeth Whitening Tooth- ...

  18. SEMICONDUCTOR TECHNOLOGY: Influence of nitrogen dose on the charge density of nitrogen-implanted buried oxide in SOI wafers

    NASA Astrophysics Data System (ADS)

    Zhongshan, Zheng; Zhongli, Liu; Ning, Li; Guohua, Li; Enxia, Zhang

    2010-02-01

    To harden silicon-on-insulator (SOI) wafers fabricated using separation by implanted oxygen (SIMOX) to total-dose irradiation, the technique of nitrogen implantation into the buried oxide (BOX) layer of SIMOX wafers can be used. However, in this work, it has been found that all the nitrogen-implanted BOX layers reveal greater initial positive charge densities, which increased with increasing nitrogen implantation dose. Also, the results indicate that excessively large nitrogen implantation dose reduced the radiation tolerance of BOX for its high initial positive charge density. The bigger initial positive charge densities can be ascribed to the accumulation of implanted nitrogen near the Si-BOX interface after annealing. On the other hand, in our work, it has also been observed that, unlike nitrogen-implanted BOX, all the fluorine-implanted BOX layers show a negative charge density. To obtain the initial charge densities of the BOX layers, the tested samples were fabricated with a metal-BOX-silicon (MBS) structure based on SIMOX wafers for high-frequency capacitance-voltage (C-V) analysis.

  19. A novel root analogue dental implant using CT scan and CAD/CAM: selective laser melting technology.

    PubMed

    Figliuzzi, M; Mangano, F; Mangano, C

    2012-07-01

    Direct laser metal forming (DLMF) is a new technique 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. Modern computed tomography (CT) acquisition and 3D image conversion, combined with the DLMF process, allows the fabrication of custom-made, root-analogue implants (RAI), perfect copies of the radicular units that need replacing. This report demonstrates the successful clinical use of a custom-made, root-analogue DLMF implant. CT images of the residual non-restorable root of a right maxillary premolar were acquired and modified with specific software into a 3D model. From this model, a custom-made, root-analogue, DLMF implant was fabricated. Immediately after tooth extraction, the root-analogue implant was placed in the extraction socket and restored with a single crown. At the 1-year follow-up examination, the custom-made implant showed almost perfect functional and aesthetic integration. The possibility of fabricating custom-made, root-analogue DLMF implants opens new interesting perspectives for immediate placement of dental implants.

  20. Science and Technology of Bio-Inert Thin Films as Hermetic-Encapsulating Coatings for Implantable Biomedical Devices: Application to Implantable Microchip in the Eye for the Artificial Retina

    NASA Astrophysics Data System (ADS)

    Auciello, Orlando; Shi, Bing

    Extensive research has been devoted to the development of neuron prostheses and hybrid bionic systems to establish links between the nervous system and electronic or robotic prostheses with the main focus of restoring motor and sensory functions in blind patients. Artificial retinas, one type of neural prostheses we are currently working on, aim to restore some vision in blind patients caused by retinitis picmentosa or macular degeneration, and in the future to restore vision at the level of face recognition, if not more. Currently there is no hermetic microchip-size coating that provides a reliable, long-term (years) performance as encapsulating coating for the artificial retina Si microchip to be implanted inside the eye. This chapter focuses on the critical topics relevant to the development of a robust, long-term artificial retina device, namely the science and technology of hermetic bio-inert encapsulating coatings to protect a Si microchip implanted in the human eye from being attacked by chemicals existing in the eye's saline environment. The work discussed in this chapter is related to the development of a novel ultrananocrystalline diamond (UNCD) hermetic coating, which exhibited no degradation in rabbit eyes. The material synthesis, characterization, and electrochemical properties of these hermetic coatings are reviewed for application as encapsulating coating for the artificial retinal microchips implantable inside the human eye. Our work has shown that UNCD coatings may provide a reliable hermetic bio-inert coating technology for encapsulation of Si microchips implantable in the eye specifically and in the human body in general. Electrochemical tests of the UNCD films grown under CH4/Ar/H2 (1%) plasma exhibit the lowest leakage currents (˜7 × 10-7 A/cm2) in a saline solution simulating the eye environment. This leakage is incompatible with the functionality of the first-generation artificial retinal microchip. However, the growth of UNCD on top of the

  1. A test microchip for evaluation of hermetic packaging technology for biomedical prosthetic implants.

    PubMed

    Kazemi, Mohammad; Basham, Eric; Sivaprakasam, Mohanasankar; Wang, Guoxing; Rodger, Damien; Weiland, James; Tai, Y C; Liu, Wentai; Humayun, Mark

    2004-01-01

    The development of a test chip that will be used to evaluate a hermetic and biocompatible package for the driving CMOS circuitry of a retinal prosthesis is described. The package design is estimated to be about 2 x 2 x 0.3 mm(3) and will be formed by conformal layers of parylene and a metal (e.g. titanium) as inner and outer protections, respectively. The test chip has been specifically designed for evaluation of the packaging technology. It consists of many blocks of analog and digital components as well as relative humidity and temperature sensors. The test chip has more probe points than a typical chip, allowing a more thorough evaluation of circuit behavior during the testing. This chip will first be coated in a layer of parylene C and soaked in heated isotonic saline for an extended period of time. Every block in the chip will then be tested for functionality using the surface probe points. The next step is to coat the surface of another test chip with parylene and a metal and repeat these soak tests. The results will then be analyzed and mean time-to-failure for the different samples will then be computed. Using the accelerated testing paradigm, these results will then be extrapolated to mean time-to-failure in the operating intraocular environment. Parylene test structures have already undergone an accelerated lifetime test and results have been analyzed.

  2. Changes in Ect2 Localization Couple Actomyosin-Dependent Cell Shape Changes to Mitotic Progression

    PubMed Central

    Matthews, Helen K.; Delabre, Ulysse; Rohn, Jennifer L.; Guck, Jochen; Kunda, Patricia; Baum, Buzz

    2012-01-01

    Summary As they enter mitosis, animal cells undergo profound actin-dependent changes in shape to become round. Here we identify the Cdk1 substrate, Ect2, as a central regulator of mitotic rounding, thus uncovering a link between the cell-cycle machinery that drives mitotic entry and its accompanying actin remodeling. Ect2 is a RhoGEF that plays a well-established role in formation of the actomyosin contractile ring at mitotic exit, through the local activation of RhoA. We find that Ect2 first becomes active in prophase, when it is exported from the nucleus into the cytoplasm, activating RhoA to induce the formation of a mechanically stiff and rounded metaphase cortex. Then, at anaphase, binding to RacGAP1 at the spindle midzone repositions Ect2 to induce local actomyosin ring formation. Ect2 localization therefore defines the stage-specific changes in actin cortex organization critical for accurate cell division. PMID:22898780

  3. Students’ Factors Affecting Undergraduates’ Perceptions of their Teaching and Learning Process within ECTS Experience

    PubMed Central

    la Fuente, Jesús De; Cardelle-Elawar, María; Peralta, F. Javier; Sánchez, M. Dolores; Martínez-Vicente, José Manuel; Zapata, Lucía

    2010-01-01

    Introduction: In the present study, we investigated the potential factors that influenced the level of students satisfaction with the teaching–learning process (TLP), from the perspective of students participating in the European Credit Transfer System (ECTS) experience. Method: A total of 1490 students from the Universities of Almería and Granada (Spain) participated in an evaluation of their class discipline area. They completed the new revised protocol for evaluating the ECTS experience. Analyses of variance were carried out, taking the following factors as independent variables: student's grade average, year in school, study discipline, credit load in terms of ECTS credits assigned to a subject, the e-learning approach. Perception of the TLP was used as the dependent variable. Results: The data analyses showed variability of the degree of statistically significance among the factors that influenced students’ perceptions of the TLP. These factors included: Student's grade average (in favor of high performers), year in school (in favor of earlier years), ECTS load (in favor of subjects with a medium load of credits), and e-learning (in favor of its use). These research findings provided evidence to explore the delineation of a potential profile of factors that trigger a favorable perception of the TLP. Discussion and Conclusion: The present findings certainly have implications to deepen our understanding of the core beliefs, commitment, and the experience in shaping the implementation of the European Higher Education Area through the ECTS. PMID:21713171

  4. Outcome of ECT by Race in the CORE Multi-Site Study

    PubMed Central

    Williams, Mark; Rummans, Teresa; Sampson, Shirlene; Knapp, Rebecca; Mueller, Martina; Husain, Mustafa M.; Fink, Max; Rasmussen, Keith; O’Connor, Kevin; Smith, Glenn; Petrides, George; Kellner, Charles H.

    2014-01-01

    Objective The authors examine the differences in outcome between black and white patients receiving ECT as a part of the CORE multi-site study. Methods A total of 624 patients were enrolled in an NIMH-funded, randomized controlled ECT trial comparing the efficacy of continuation ECT versus continuation pharmacotherapy between 1997 and 2004. This analysis focuses on the 32 black and 483 white patients who participated in phase I of the study. The authors compared baseline demographic and clinical variables, and acute outcomes of these two groups. Results Compared to whites, far fewer blacks participated in the study. Those who did were less likely to have failed adequate medication trials and were more likely to have psychotic features. Their initial HAMD24 scores were higher than whites, and they showed a greater reduction in these HAMD24 scores by the end of the treatment period. While sample size limited the statistical significance of the findings, black patients also showed a higher rate of remission after an acute phase of ECT. Conclusions This study found that black and white patients with major depressive disorder had comparable outcomes. We also found that fewer black patients received ECT than whites, a difference that has been reported in other samples. PMID:18580553

  5. Electroconvulsive therapy: Part I. A perspective on the evolution and current practice of ECT.

    PubMed

    Payne, Nancy A; Prudic, Joan

    2009-09-01

    The concept of inducing convulsions, mainly through chemical means, to promote mental wellness has existed since the 16th century. In 1938, Italian scientists first applied electrically induced therapeutic seizures. Although electroconvulsive therapy (ECT) is employed in the treatment of several psychiatric disorders, it is most frequently used today to treat severe depressive episodes and remains the most effective treatment available for those disorders. Despite this, ECT continues to be the most stigmatized treatment available in psychiatry, resulting in restrictions on and reduced accessibility to a helpful and potentially life-saving treatment. The psychiatric and psychosocial ramifications of this stigmatization may include the exacerbation of the increasingly serious, global health problem of major depressive disorders as well as serious consequences for individual patients who may not be offered, or may refuse, a potentially beneficial treatment. The goal of this first article in this two-part series is to provide an overview of ECT's historical development and discuss the current state of knowledge about ECT, including technical aspects of delivery, patient selection, its side-effect profile, and factors that may contribute to underuse of ECT.

  6. Cochlear implantation: a biomechanical prosthesis for hearing loss

    PubMed Central

    Yawn, Robert; Hunter, Jacob B.; Sweeney, Alex D.

    2015-01-01

    Cochlear implants are a medical prosthesis used to treat sensorineural deafness, and one of the greatest advances in modern medicine. The following article is an overview of cochlear implant technology. The history of cochlear implantation and the development of modern implant technology will be discussed, as well as current surgical techniques. Research regarding expansion of candidacy, hearing preservation cochlear implantation, and implantation for unilateral deafness are described. Lastly, innovative technology is discussed, including the hybrid cochlear implant and the totally implantable cochlear implant. PMID:26097718

  7. Use of ECT in Nepal: A One Year Study From the Country’s Largest Psychiatric Facility

    PubMed Central

    Aich, Tapas Kumar; Sharma, Niru

    2016-01-01

    Introduction Electro-Convulsive Therapy (ECT) refers to the electrical stimulation of the brain to produce seizures for therapeutic purpose. Since the development of ECT, it’s use has been consistent. Inspite of the common use, data pertaining to the use of ECT in Nepal is lacking. Aim This study was undertaken with the aim of exploring the clinico-demographic profile of patients treated with ECT in the largest psychiatry facility in the country. Materials and Methods It is a retrospective descriptive study of patients who were treated with ECT after admission in the inpatient psychiatry unit of Universal College of Medical Sciences Teaching Hospital, Bhairahawa, Nepal during a period of one year (August 2012 to July 2013). Results Out of 1095 patients admitted during the specified period, 81 (7.39%) patients received ECT. About 44.44% of the patients belonged to 20-29 years age group. Female patients constituted more than half of the subjects (55.56%). Review of diagnostic profile showed that majority of patients receiving ECT were suffering from Schizophrenia (44.4%), followed by Bipolar Affective Disorder/Mania (29.6%), Depressive disorder (11.1%), Acute and Transient Psychotic Disorder (6.2%), Post-partum Psychosis (3.7%) and substance induced mood/psychotic disorders (3.7%). A significant majority of subjects (75.3%) received about 5-7 ECT treatments. The mean seizure duration after ECT treatment was 31.13±5.79 seconds. No any major complications were noted during ECT treatment. Conclusion This study suggests that ECT, use, as a treatment modality is common in young adults and females with Schizophrenia being the most common indication. Direct ECT is safe when used judiciously. PMID:27042563

  8. Letter to the editor: The effect of ECT on sleep--a comment to Winkler et al.

    PubMed

    McCall, W Vaughn; Rosenquist, Peter B

    2015-02-01

    Recent publications in this journal have suggested that successful electroconvulsive therapy (ECT) in depressed patients is associated with a phase advance, similar to what has been reported with antidepressant medications. Herein we review the effects of ECT on polysomnographic (PSG) sleep, and we conclude with the observation that ECT reliably increases PSG total sleep time and probably has a suppressive effect on rapid eye movement (REM) sleep. Remarkably, there is less information available on the topic of the effect of ECT on the patient's perception of their sleep. PMID:25434521

  9. Toxoplasmosis Infection and Cognitive Deficit after Electroconvulsive Treatment (ECT), Is There a Connection?

    PubMed Central

    E. Berg, John

    2012-01-01

    Electroconvulsive treatment (ECT) has developed over 70 years to a modern, effective way of lifting depressive moods. Memory loss and visual acuity after electroconvulsive treatment is the only remaining relevant criticism of the treatment modality when considering the overall rate of remission from this treatment compared to all other treatment modalities. A depressive state impedes memory, and memory improves on several qualities of cognition after treatment. However, the comparison of a person’s memory ability from the months before depression started to the level after a course of ECT is never performed, for obvious reasons. Some infectious diseases are known to influence memory negatively through effects on the dopamine receptors. More specifically, former toxoplasmosis infection may be a factor. Preliminary data on titres of toxoplasma IgG may indicate a connection to the development of long-standing memory problems after ECT. PMID:24600630

  10. Dental Implant Systems

    PubMed Central

    Oshida, Yoshiki; Tuna, Elif B.; Aktören, Oya; Gençay, Koray

    2010-01-01

    Among various dental materials and their successful applications, a dental implant is a good example of the integrated system of science and technology involved in multiple disciplines including surface chemistry and physics, biomechanics, from macro-scale to nano-scale manufacturing technologies and surface engineering. As many other dental materials and devices, there are crucial requirements taken upon on dental implants systems, since surface of dental implants is directly in contact with vital hard/soft tissue and is subjected to chemical as well as mechanical bio-environments. Such requirements should, at least, include biological compatibility, mechanical compatibility, and morphological compatibility to surrounding vital tissues. In this review, based on carefully selected about 500 published articles, these requirements plus MRI compatibility are firstly reviewed, followed by surface texturing methods in details. Normally dental implants are placed to lost tooth/teeth location(s) in adult patients whose skeleton and bony growth have already completed. However, there are some controversial issues for placing dental implants in growing patients. This point has been, in most of dental articles, overlooked. This review, therefore, throws a deliberate sight on this point. Concluding this review, we are proposing a novel implant system that integrates materials science and up-dated surface technology to improve dental implant systems exhibiting bio- and mechano-functionalities. PMID:20480036

  11. Current trends in dental implants

    PubMed Central

    Gaviria, Laura; Salcido, John Paul; Guda, Teja

    2014-01-01

    Tooth loss is very a very common problem; therefore, the use of dental implants is also a common practice. Although research on dental implant designs, materials and techniques has increased in the past few years and is expected to expand in the future, there is still a lot of work involved in the use of better biomaterials, implant design, surface modification and functionalization of surfaces to improve the long-term outcomes of the treatment. This paper provides a brief history and evolution of dental implants. It also describes the types of implants that have been developed, and the parameters that are presently used in the design of dental implants. Finally, it describes the trends that are employed to improve dental implant surfaces, and current technologies used for the analysis and design of the implants. PMID:24868501

  12. Current trends in dental implants.

    PubMed

    Gaviria, Laura; Salcido, John Paul; Guda, Teja; Ong, Joo L

    2014-04-01

    Tooth loss is very a very common problem; therefore, the use of dental implants is also a common practice. Although research on dental implant designs, materials and techniques has increased in the past few years and is expected to expand in the future, there is still a lot of work involved in the use of better biomaterials, implant design, surface modification and functionalization of surfaces to improve the long-term outcomes of the treatment. This paper provides a brief history and evolution of dental implants. It also describes the types of implants that have been developed, and the parameters that are presently used in the design of dental implants. Finally, it describes the trends that are employed to improve dental implant surfaces, and current technologies used for the analysis and design of the implants.

  13. Noise reduction technologies implemented in head-worn preprocessors for improving cochlear implant performance in reverberant noise fields.

    PubMed

    Chung, King; Nelson, Lance; Teske, Melissa

    2012-09-01

    The purpose of this study was to investigate whether a multichannel adaptive directional microphone and a modulation-based noise reduction algorithm could enhance cochlear implant performance in reverberant noise fields. A hearing aid was modified to output electrical signals (ePreprocessor) and a cochlear implant speech processor was modified to receive electrical signals (eProcessor). The ePreprocessor was programmed to flat frequency response and linear amplification. Cochlear implant listeners wore the ePreprocessor-eProcessor system in three reverberant noise fields: 1) one noise source with variable locations; 2) three noise sources with variable locations; and 3) eight evenly spaced noise sources from 0° to 360°. Listeners' speech recognition scores were tested when the ePreprocessor was programmed to omnidirectional microphone (OMNI), omnidirectional microphone plus noise reduction algorithm (OMNI + NR), and adaptive directional microphone plus noise reduction algorithm (ADM + NR). They were also tested with their own cochlear implant speech processor (CI_OMNI) in the three noise fields. Additionally, listeners rated overall sound quality preferences on recordings made in the noise fields. Results indicated that ADM+NR produced the highest speech recognition scores and the most preferable rating in all noise fields. Factors requiring attention in the hearing aid-cochlear implant integration process are discussed.

  14. Reflections on Rodent Implantation.

    PubMed

    Cha, Jeeyeon M; Dey, Sudhansu K

    2015-01-01

    Embryo implantation is a complex process involving endocrine, paracrine, autocrine, and juxtacrine modulators that span cell-cell and cell-matrix interactions. The quality of implantation is predictive for pregnancy success. Earlier observational studies formed the basis for genetic and molecular approaches that ensued with emerging technological advances. However, the precise sequence and details of the molecular interactions involved have yet to be defined. This review reflects briefly on aspects of our current understanding of rodent implantation as a tribute to Roger Short's lifelong contributions to the field of reproductive physiology. PMID:26450495

  15. The role of APOE-ɛ4 and beta amyloid in the differential rate of recovery from ECT: a review.

    PubMed

    Sutton, T A; Sohrabi, H R; Rainey-Smith, S R; Bird, S M; Weinborn, M; Martins, R N

    2015-03-31

    Individual biological differences may contribute to the variability of outcomes, including cognitive effects, observed following electroconvulsive treatment (ECT). A narrative review of the research literature on carriage of the apolipoprotein E ɛ4 allele (APOE-ɛ4) and the protein biomarker beta amyloid (Aβ) with ECT cognitive outcome was undertaken. ECT induces repeated brain seizures and there is debate as to whether this causes brain injury and long-term cognitive disruption. The majority of ECT is administered to the elderly (over age 65 years) with drug-resistant depression. Depression in the elderly may be a symptom of the prodromal stage of Alzheimer's disease (AD). Carriage of the APOE-ɛ4 allele and raised cerebral Aβ are consistently implicated in AD, but inconsistently implicated in brain injury (and related syndromes) recovery rates. A paucity of brain-related recovery, genetic and biomarker research in ECT responses in the elderly was found: three studies have examined the effect of APOE-ɛ4 allele carriage on cognition in the depressed elderly receiving ECT, and two have examined Aβ changes after ECT, with contradictory findings. Cognitive changes in all studies of ECT effects were measured by a variety of psychological tests, making comparisons of such changes between studies problematic. Further, psychological test data-validity measures were not routinely administered, counter to current testing recommendations. The methodological issues of the currently available literature as well as the need for well-designed, hypothesis driven, longitudinal studies are discussed.

  16. The role of APOE-ɛ4 and beta amyloid in the differential rate of recovery from ECT: a review

    PubMed Central

    Sutton, T A; Sohrabi, H R; Rainey-Smith, S R; Bird, S M; Weinborn, M; Martins, R N

    2015-01-01

    Individual biological differences may contribute to the variability of outcomes, including cognitive effects, observed following electroconvulsive treatment (ECT). A narrative review of the research literature on carriage of the apolipoprotein E ɛ4 allele (APOE-ɛ4) and the protein biomarker beta amyloid (Aβ) with ECT cognitive outcome was undertaken. ECT induces repeated brain seizures and there is debate as to whether this causes brain injury and long-term cognitive disruption. The majority of ECT is administered to the elderly (over age 65 years) with drug-resistant depression. Depression in the elderly may be a symptom of the prodromal stage of Alzheimer's disease (AD). Carriage of the APOE-ɛ4 allele and raised cerebral Aβ are consistently implicated in AD, but inconsistently implicated in brain injury (and related syndromes) recovery rates. A paucity of brain-related recovery, genetic and biomarker research in ECT responses in the elderly was found: three studies have examined the effect of APOE-ɛ4 allele carriage on cognition in the depressed elderly receiving ECT, and two have examined Aβ changes after ECT, with contradictory findings. Cognitive changes in all studies of ECT effects were measured by a variety of psychological tests, making comparisons of such changes between studies problematic. Further, psychological test data-validity measures were not routinely administered, counter to current testing recommendations. The methodological issues of the currently available literature as well as the need for well-designed, hypothesis driven, longitudinal studies are discussed. PMID:25826114

  17. Debunking EHEA Myths: Common ECTS Misconceptions and Why They Are Wrong

    ERIC Educational Resources Information Center

    Pérez Cañado, María Luisa

    2009-01-01

    The present article seeks to overcome some of the most common misconceptions which are currently proliferating in the application of the "European Credit Transfer System" (ECTS) at tertiary level. It presents and unpacks seven false myths affecting all the main curricular and organizational levels of the implementation of the new credit…

  18. Applying the ECTS System to the Childhood Education Teaching Degree in Andalusia

    ERIC Educational Resources Information Center

    Serrano, Rosario Merida; Romero, Julia Angulo; Del Pino, Carmen Gil

    2008-01-01

    This article presents the research conducted as part of a Pilot Experiment regarding the application of the ECTS to the Childhood Education Teaching Degree taught at the University of Cordoba (Spain). It analyses the Experiment, which was carried out in the Education Faculty over the course of three academic years (2004/05, 2005/06 and 2006/07).…

  19. An Assessment of the ECTS in Software Engineering: A Teaching Experience

    ERIC Educational Resources Information Center

    Salas-Morera, L.; Berral-Yeron, J.; Serrano-Gomez, I.; Martinez-Jimenez, P.

    2009-01-01

    Spain is currently implementing the regulatory modifications promulgated by the Declaration of Bologna, which should result in the updating of the structure of university degrees, and the inclusion of the European Credit Transfer and Accumulation System (ECTS) methodology. In some Spanish universities, the experimental adoption of this methodology…

  20. Top Ten Reasons a Graduate Student Should Apply to Be an ECT Foundation Intern

    ERIC Educational Resources Information Center

    York, Cindy S.

    2009-01-01

    In this article, the author encourages graduate students to apply for the ECT Foundation Internship. She presents a list of the top ten benefits the internship offers a graduate student's career: (1) It could change your life. It changed mine; (2) Networking; (3) Mentoring; (4) Leadership opportunities; (5) Behind the scenes pass; (6) Shadowing;…

  1. Cochlear Implants

    MedlinePlus

    ... electrodes are inserted. The electronic device at the base of the electrode array is then placed under ... FDA approval for implants The Food and Drug Administration (FDA) regulates cochlear implant devices for both adults ...

  2. Dental Implants.

    PubMed

    Zohrabian, Vahe M; Sonick, Michael; Hwang, Debby; Abrahams, James J

    2015-10-01

    Dental implants restore function to near normal in partially or completely edentulous patients. A root-form implant is the most frequently used type of dental implant today. The basis for dental implants is osseointegration, in which osteoblasts grow and directly integrate with the surface of titanium posts surgically embedded into the jaw. Radiologic assessment is critical in the preoperative evaluation of the dental implant patient, as the exact height, width, and contour of the alveolar ridge must be determined. Moreover, the precise locations of the maxillary sinuses and mandibular canals, as well as their relationships to the site of implant surgery must be ascertained. As such, radiologists must be familiar with implant design and surgical placement, as well as augmentation procedures utilized in those patients with insufficient bone in the maxilla and mandible to support dental implants.

  3. Science Highlights from the RBSP-ECT Particle Instrument Suite on NASA's Van Allen Probes Mission

    NASA Astrophysics Data System (ADS)

    Spence, Harlan

    2014-05-01

    The NASA Van Allen Probes mission includes an instrument suite known as the Radiation Belt Storm Probes (RBSP) - Energetic Particle, Composition, and Thermal Plasma (ECT) suite. RBSP-ECT contains a well-proven complement of particle instruments to ensure the highest quality measurements ever made in the radiation belts and the inner magnetosphere. The coordinated RBSP-ECT particle measurements, analyzed in combination with fields and waves observations and state of-the-art theory and modeling, provide new understanding on the acceleration, global distribution, and variability of radiation belt electrons and ions, key science objectives of NASA's Living With a Star program and the Van Allen Probes mission. The RBSP-ECT suite consists of three highly-coordinated instruments: the Helium Oxygen Proton Electron (HOPE) spectrometer, the Magnetic Electron Ion Spectrometer (MagEIS), and the Relativistic Electron Proton Telescope (REPT). Collectively these three instrument types cover comprehensively the full electron and ion spectra from one eV to 10's of MeV with sufficient energy resolution, pitch angle coverage and resolution, and with composition measurements in the critical energy range up to 50 keV and also from a few to 50 MeV/nucleon. All three instruments are based on measurement techniques proven in the radiation belts, then optimized to provide unambiguous separation of ions and electrons and clean energy responses even in the presence of extreme penetrating background environments. In this presentation, we summarize overall ECT science goals and then show scientific results derived from the ECT suite on the dual Van Allen Probes spacecraft to date. Mission operations began only in late October 2012, and we have now achieved significant results. Results presented here will include substantial progress toward resolving primary Van Allen Probes science targets, such as: the relative role of localized acceleration versus transport-generated particle acceleration

  4. Early Science Results From the NASA Van Allen Probes Mission RBSP-ECT Instrument Suite

    NASA Astrophysics Data System (ADS)

    Spence, Harlan; Reeves, Geoff; Rbspect Team

    2013-04-01

    The NASA Van Allen Probes mission includes an instrument suite known as the Radiation Belt Storm Probes (RBSP) - Energetic Particle, Composition, and Thermal Plasma (ECT) suite. RBSP-ECT contains a well-proven complement of particle instruments to ensure the highest quality measurements ever made in the radiation belts and the inner magnetosphere. The coordinated RBSP-ECT particle measurements, analyzed in combination with fields and waves observations and state of-the-art theory and modeling, provide new understanding on the acceleration, global distribution, and variability of radiation belt electrons and ions, key science objectives of NASA's Living With a Star program and the Van Allen Probes mission. The RBSP-ECT suite consists of three highly-coordinated instruments: the Helium Oxygen Proton Electron (HOPE) spectrometer, the Magnetic Electron Ion Spectrometer (MagEIS), and the Relativistic Electron Proton Telescope (REPT). Collectively these three instrument types cover comprehensively the full electron and ion spectra from one eV to 10's of MeV with sufficient energy resolution, pitch angle coverage and resolution, and with composition measurements in the critical energy range up to 50 keV and also from a few to 50 MeV/nucleon. All three instruments are based on measurement techniques proven in the radiation belts, then optimized to provide unambiguous separation of ions and electrons and clean energy responses even in the presence of extreme penetrating background environments. In this presentation, we summarize overall ECT science goals and then show early scientific results derived from the ECT suite on the dual Van Allen Probes spacecraft. Mission operations began only in late October 2012, but we have already achieved significant early results. Results presented here will include substantial progress toward resolving primary Van Allen Probes science targets, such as: the relative role of localized acceleration versus transport-generated particle

  5. Annexin V-induced rat Leydig cell proliferation involves Ect2 via RhoA/ROCK signaling pathway.

    PubMed

    Jing, Jun; Chen, Li; Fu, Hai-Yan; Fan, Kai; Yao, Qi; Ge, Yi-Feng; Lu, Jin-Chun; Yao, Bing

    2015-01-01

    This study investigated the effect of annexin V on the proliferation of primary rat Leydig cells and the potential mechanism. Our results showed that annexin V promoted rat Leydig cell proliferation and cell cycle progression in a dose- and time-dependent manner. Increased level of annexin V also enhanced Ect2 protein expression. However, siRNA knockdown of Ect2 attenuated annexin V-induced proliferation of rat Leydig cells. Taken together, these data suggest that increased level of annexin V induced rat Leydig cell proliferation and cell cycle progression via Ect2. Since RhoA activity was increased following Ect2 activation, we further investigated whether Ect2 was involved in annexin V-induced proliferation via the RhoA/ROCK pathway, and the results showed that annexin V increased RhoA activity too, and this effect was abolished by the knockdown of Ect2. Moreover, inhibition of the RhoA/ROCK pathway by a ROCK inhibitor, Y27632, also attenuated annexin V-induced proliferation and cell cycle progression. We thus conclude that Ect2 is involved in annexin V-induced rat Leydig cell proliferation through the RhoA/ROCK pathway. PMID:25807302

  6. Annexin V-induced rat Leydig cell proliferation involves Ect2 via RhoA/ROCK signaling pathway.

    PubMed

    Jing, Jun; Chen, Li; Fu, Hai-Yan; Fan, Kai; Yao, Qi; Ge, Yi-Feng; Lu, Jin-Chun; Yao, Bing

    2015-03-24

    This study investigated the effect of annexin V on the proliferation of primary rat Leydig cells and the potential mechanism. Our results showed that annexin V promoted rat Leydig cell proliferation and cell cycle progression in a dose- and time-dependent manner. Increased level of annexin V also enhanced Ect2 protein expression. However, siRNA knockdown of Ect2 attenuated annexin V-induced proliferation of rat Leydig cells. Taken together, these data suggest that increased level of annexin V induced rat Leydig cell proliferation and cell cycle progression via Ect2. Since RhoA activity was increased following Ect2 activation, we further investigated whether Ect2 was involved in annexin V-induced proliferation via the RhoA/ROCK pathway, and the results showed that annexin V increased RhoA activity too, and this effect was abolished by the knockdown of Ect2. Moreover, inhibition of the RhoA/ROCK pathway by a ROCK inhibitor, Y27632, also attenuated annexin V-induced proliferation and cell cycle progression. We thus conclude that Ect2 is involved in annexin V-induced rat Leydig cell proliferation through the RhoA/ROCK pathway.

  7. Superelastic Orthopedic Implant Coatings

    NASA Astrophysics Data System (ADS)

    Fournier, Eric; Devaney, Robert; Palmer, Matthew; Kramer, Joshua; El Khaja, Ragheb; Fonte, Matthew

    2014-07-01

    The demand for hip and knee replacement surgery is substantial and growing. Unfortunately, most joint replacement surgeries will fail within 10-25 years, thereby requiring an arduous, painful, and expensive revision surgery. To address this issue, a novel orthopedic implant coating material ("eXalt") has been developed. eXalt is comprised of super elastic nitinol wire that is knit into a three-dimensional spacer fabric structure. eXalt expands in vivo to conform to the implantation site and is porous to allow for bone ingrowth. The safety and efficacy of eXalt were evaluated through structural analysis, mechanical testing, and a rabbit implantation model. The results demonstrate that eXalt meets or exceeds the performance of current coating technologies with reduced micromotion, improved osseointegration, and stronger implant fixation in vivo.

  8. Improve the corrosion and cytotoxic behavior of NiTi implants with use of the ion beam technologies

    SciTech Connect

    Meisner, L. L. Meisner, S. N.; Matveeva, V. A.; Matveev, A. L.

    2015-11-17

    The corrosion resistance behavior and cytotoxicity of binary NiTi-base alloy specimens subjected to surface modification by silicon ion beams and the proliferative ability of mesenchymal stem cells (MSC) of rat marrow on an ion-implanted surface of the alloy have been studied. The silicon ion beam processing of specimen surfaces is shown to bring about a nearly two-fold improvement in the corrosion resistance of the material to attack by acqueous solutions of NaCl and human plasma and a drastic decrease in the nickel concentration after immersion of the specimens into the solutions for ∼3400 and ∼6000 h, respectively. It is found that MSC proliferation strongly depends on the surface structure, roughness and chemical condition of NiTi implants.

  9. Improve the corrosion and cytotoxic behavior of NiTi implants with use of the ion beam technologies

    NASA Astrophysics Data System (ADS)

    Meisner, L. L.; Matveeva, V. A.; Meisner, S. N.; Matveev, A. L.

    2015-11-01

    The corrosion resistance behavior and cytotoxicity of binary NiTi-base alloy specimens subjected to surface modification by silicon ion beams and the proliferative ability of mesenchymal stem cells (MSC) of rat marrow on an ion-implanted surface of the alloy have been studied. The silicon ion beam processing of specimen surfaces is shown to bring about a nearly two-fold improvement in the corrosion resistance of the material to attack by acqueous solutions of NaCl and human plasma and a drastic decrease in the nickel concentration after immersion of the specimens into the solutions for ˜3400 and ˜6000 h, respectively. It is found that MSC proliferation strongly depends on the surface structure, roughness and chemical condition of NiTi implants.

  10. Drug Delivery: Enabling Technology for Drug Discovery and Development. iPRECIO Micro Infusion Pump: Programmable, Refillable, and Implantable.

    PubMed

    Tan, Tsung; Watts, Stephanie W; Davis, Robert Patrick

    2011-01-01

    Successful drug delivery using implantable pumps may be found in over 12,500 published articles. Their versatility in delivering continuous infusion, intermittent or complex infusion protocols acutely or chronically has made them ubiquitous in drug discovery and basic research. The recent availability of iPRECIO(®), a programmable, refillable, and implantable infusion pump has made it possible to carry out quantitative pharmacology (PKPD) in single animals. When combined with specialized catheters, specific administration sites have been selected. When combined with radiotelemetry, the physiologic gold standard, more sensitive and powerful means of detecting drug induced therapeutic, and/or adverse effects has been possible. Numerous application examples are cited from iPRECIO(®) use in Japan, United States, and Europe with iPRECIO(®) as an enabling drug delivery device where the refillable and programmability functionality were key benefits. The ability to start/stop drug delivery and to have control periods prior dosing made it possible to have equivalent effects at a much lower dose than previously studied. Five different iPRECIO(®) applications are described in detail with references to the original work where the implantable, refillable, and programmable benefits are demonstrated with their different end-points.

  11. A Case Report of Prolonged Apnea during ECT in a Patient with Suicidal Attempt by Organophosphorus Poison.

    PubMed

    Moudi, Sussan; Alijanpour, Ebrahim; Manouchehri, Ali-Asghar; Jafarian, Hasan

    2012-01-01

    Organophosphorus pesticides have been used in some cases for suicidal attempts. Such poison can affect plasma cholinesterase activity. The case was a 47-year-old man hospitalized due to suicide attempt with swallowing agricultural poison. The patient, diagnosed with major depressive disorder (MDD), underwent treatment with electroconvulsive therapy (ECT). At the first ECT session, the patient developed apnea for 45 minutes following receiving 20 mg succinylcholine. The patient was intubated; after restoration of respiration depth and rate, the patient was extubated. Collectively, in cases with history of suicide attempts, taking organophosphorus pesticides should be warn for pre-ECT anesthesia. PMID:24644472

  12. A Case Report of Prolonged Apnea during ECT in a Patient with Suicidal Attempt by Organophosphorus Poison

    PubMed Central

    Moudi, Sussan; Alijanpour, Ebrahim; Manouchehri, Ali-asghar; Jafarian, Hasan

    2012-01-01

    Organophosphorus pesticides have been used in some cases for suicidal attempts. Such poison can affect plasma cholinesterase activity. The case was a 47-year-old man hospitalized due to suicide attempt with swallowing agricultural poison. The patient, diagnosed with major depressive disorder (MDD), underwent treatment with electroconvulsive therapy (ECT). At the first ECT session, the patient developed apnea for 45 minutes following receiving 20 mg succinylcholine. The patient was intubated; after restoration of respiration depth and rate, the patient was extubated. Collectively, in cases with history of suicide attempts, taking organophosphorus pesticides should be warn for pre-ECT anesthesia. PMID:24644472

  13. Simplified data reduction methods for the ECT test for mode 3 interlaminar fracture toughness

    NASA Technical Reports Server (NTRS)

    Li, Jian; Obrien, T. Kevin

    1995-01-01

    Simplified expressions for the parameter controlling the load point compliance and strain energy release rate were obtained for the Edge Crack Torsion (ECT) specimen for mode 3 interlaminar fracture toughness. Data reduction methods for mode 3 toughness based on the present analysis are proposed. The effect of the transverse shear modulus, G(sub 23), on mode 3 interlaminar fracture toughness characterization was evaluated. Parameters influenced by the transverse shear modulus were identified. Analytical results indicate that a higher value of G(sub 23) results in a low load point compliance and lower mode 3 toughness estimation. The effect of G(sub 23) on the mode 3 toughness using the ECT specimen is negligible when an appropriate initial delamination length is chosen. A conservative estimation of mode 3 toughness can be obtained by assuming G(sub 23) = G(sub 12) for any initial delamination length.

  14. [Subretinal visual implants].

    PubMed

    Stingl, K; Greppmaier, U; Wilhelm, B; Zrenner, E

    2010-12-01

    Visual implants are medical technologies that replace parts of the visual neuronal pathway. The subretinal implant developed by our group is being used in a human trials since 2005 and replaces the function of degenerated photoreceptors by an electronic device in blind patients. The subretinal implant consists of a 70-µm thin microchip with 1500 microphotodiodes each with an amplifier and an electrode with area of 3 mm × 3 mm. The power supply is provided by a subdermal power supply cable. The microchip is implanted under the macula and transforms the light signal into an electrical one, which is referred directly to the bipolar cells. Requirements for a good function of the implant are a preserved function of the inner retina, as well as clear optic media and a good visual acuity in the earlier life. The current technology can mediate a visual field of 10 - 12° and a computed resolution of up to 0.25° visual angle (corresponding to a visual acuity of 63 / 1000 - 80 / 1000) in blind patients. The so far best results from our studies reached a visual acuity of 21 / 1000 in blind retinitis pigmentosa patients. This overview is intended to inform the ophthalmologist about the current state of the technology and help him/her to advise interested patients.

  15. [Anti-NMDA encephalitis in psychiatry; malignant catatonia, atypical psychosis and ECT].

    PubMed

    Kanbayashi, Takashi; Tsutsui, Ko; Tanaka, Keiko; Omori, Yuki; Takaki, Manabu; Omokawa, Mayu; Mori, Akane; Kusanagi, Hiroaki; Nishino, Seiji; Shimizu, Tetsuo

    2014-01-01

    The symptoms of malignant (lethal) catatonia has been reported similar to initial symptoms of anti-NMDAR encephalitis. Subsequently, this autoimmune limbic encephalitis has been noticed in many psychiatrists. We have experienced several cases with malignant catatonia having anti-NMDAR antibody without clinical signs of encephalitis. Thereafter, we have also found anti-NMDAR antibody positive patients of young females with acute florid psychiatric symptoms without clinical signs of encephalitis. The features of these patients mirror-those of "Atypical psychosis" proposed by Mitsuda in Japan, a notion derived from "Cycloid psychosis" conceptualized by German psychiatrist, Leonhard. Both cycloid and atypical psychosis have coinciding features of acute onset, emotional disturbances, psychomotor disturbances, alternations of consciousness, high prevalence in women and oriented premorbid personality. Both malignant catatonia and atypical psychosis have been known to be effectively treated with modified electro convulsion therapy (m-ECT). Our 5 cases with anti-NMDAR antibody, m-ECT treatments were effective. Infectious encephalitis is contra indication of m-ECT, but this autoimmune encephalitis would be careful indication. Schizophrenia is a common, heterogeneous, and complex disorder with unknown etiology. There is established evidence of NMDAR hypofunction as a central component of the functional disconnectivity; this is one of the most accepted models for schizophrenia. Moreover, autoimmune mechanisms have been proposed to be involved, at least in subgroups of schizophrenia patients. Further research of anti-NMDAR antibody and encephalitis would be important clues for the investigation of schizophrenia, catatonia and atypical psychosis.

  16. ASIC or PIC? Implantable stimulators based on semi-custom CMOS technology or low-power microcontroller architecture.

    PubMed

    Salmons, S; Gunning, G T; Taylor, I; Grainger, S R; Hitchings, D J; Blackhurst, J; Jarvis, J C

    2001-01-01

    To gain a better understanding of the effects of chronic stimulation on mammalian muscles we needed to generate patterns of greater variety and complexity than simple constant-frequency or burst patterns. We describe here two approaches to the design of implantable neuromuscular stimulators that can satisfy these requirements. Devices of both types were developed and used in long-term experiments. The first device was based on a semi-custom Application Specific Integrated Circuit (ASIC). This approach has the advantage that the circuit can be completely tested at every stage of development and production, assuring a high degree of reliability. It has the drawback of inflexibility: the patterns are produced by state machines implemented in silicon, so each new set of patterns requires a fresh production run, which is costly and time-consuming. The second device was based on a commercial microcontroller (Microchip PIC16C84). The functionality of this type of circuit is specified in software rather than in silicon hardware, allowing a single device to be programmed for different functions. With the use of features designed to improve fault-tolerance we found this approach to be as reliable as that based on ASICs. The encapsulated devices can easily be accommodated subcutaneously on the flank of a rabbit and a recent version is small enough to implant into the peritoneal cavity of rats. The current devices are programmed with a predetermined set of 12 patterns before assembly; the desired pattern is selected after implantation with an electronic flash gun. The operating current drain is less than 40 microA.

  17. Histrelin Implant

    MedlinePlus

    ... response to histrelin implant. Your blood sugar and glycosylated hemoglobin (HbA1c) should be checked regularly.Ask your pharmacist any questions you have about histrelin implant.It is important for you to keep a written list of all of the prescription and ...

  18. Implantable Heart Aid

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Medrad utilized NASA's Apollo technology to develop a new device called the AID implantable automatic pulse generator which monitors the heart continuously, recognizes the onset of ventricular fibrillation and delivers a corrective electrical shock. AID pulse generator is, in effect, a miniaturized version of the defibrillator used by emergency squads and hospitals to restore rhythmic heartbeat after fibrillation, but has the unique advantage of being permanently available to the patient at risk. Once implanted, it needs no specially trained personnel or additional equipment. AID system consists of a microcomputer, a power source and two electrodes which sense heart activity.

  19. Semiconductor Ion Implanters

    NASA Astrophysics Data System (ADS)

    MacKinnon, Barry A.; Ruffell, John P.

    2011-06-01

    In 1953 the Raytheon CK722 transistor was priced at 7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at 6.2 billion! Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing `only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around 2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

  20. Semiconductor Ion Implanters

    SciTech Connect

    MacKinnon, Barry A.; Ruffell, John P.

    2011-06-01

    In 1953 the Raytheon CK722 transistor was priced at $7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at $6.2 billion. Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing 'only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around $2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

  1. [Successful amantadine treatment of a patient with ECT-resistant catatonia].

    PubMed

    Walstra, A N; den Broek, M VAN; Giltay, E J; van Paassen, J; van Noorden, M S

    2016-01-01

    Catatonia is a common neuropsychiatric syndrome. There is a life-threatening subtype of this disease known as malignant catatonia. One of the hypotheses regarding the pathogenesis is an imbalance of multiple neurotransmitters (gaba, glutamate and dopamine). The first step in treatment is to administer benzodiazepines; if the response is insufficient, the treatment can be replaced by electroconvulsive therapy (ect). So far, there is no consensus with regard to the tertiary treatment step. On the basis of a case report we describe the beneficial effects of administering an nmda receptor antagonist, amantadine, as the tertiary step for treating a patient with treatment-resistant malignant catatonia. PMID:27527886

  2. Cochlear implant

    MedlinePlus

    ... implant. These specialists may include: Audiologists Speech therapists Ear, nose, and throat doctors (otolaryngologists) This is a very important part of the process. You will need to work closely with your team of specialists to get ...

  3. Cochlear Implants

    MedlinePlus

    ... additional visits are needed for activating, adjusting, and programming the various electrodes that have been implanted. Also, ... to the center for checkups once the final programming is made to the speech processor. Both children ...

  4. Information Technology for Workplace Communication. Workscape 21: The Ecology of New Ways of Working.

    ERIC Educational Resources Information Center

    Becker, Franklin; Tennessen, Carolyn M.; Young, David

    A study was undertaken to understand the role of electronic communication technologies (ECTs) in maintaining work-related communication. The study site was Sun Microsystems, a company at the high end of the curve in terms of its commitment to and employees' experience with ECTs. An electronic focus group (n=40, 4% response) and an e-mail survey…

  5. Electronic Communications Technologies and the Transition to College: Links to Parent-Child Attachment and Adjustment

    ERIC Educational Resources Information Center

    Sarigiani, Pamela A.; Trumbell, Jill M.; Camarena, Phame M.

    2013-01-01

    Electronic communications technologies (ECTs) help college students and parents remain in contact. Because recent reports have emphasized a link between ECTs, helicopter parenting, and autonomy issues, this study focused on the significance of contact patterns for attachment and student adjustment. First-semester college students (199 female, 81…

  6. Contraceptive implants.

    PubMed

    McDonald-Mosley, Raegan; Burke, Anne E

    2010-03-01

    Implantable contraception has been extensively used worldwide. Implants are one of the most effective and reversible methods of contraception available. These devices may be particularly appropriate for certain populations of women, including women who cannot use estrogen-containing contraception. Implants are safe for use by women with many chronic medical problems. The newest implant, Implanon (Organon International, Oss, The Netherlands), is the only device currently available in the United States and was approved in 2006. It is registered for 3 years of pregnancy prevention. Contraceptive implants have failure rates similar to tubal ligation, and yet they are readily reversible with a return to fertility within days of removal. Moreover, these contraceptive devices can be safely placed in the immediate postpartum period, ensuring good contraceptive coverage for women who may be at risk for an unintended pregnancy. Irregular bleeding is a common side effect for all progestin-only contraceptive implants. Preinsertion counseling should address possible side effects, and treatment may be offered to women who experience prolonged or frequent bleeding.

  7. Extraoral Cementation Technique to Minimize Cement-Associated Peri-implant Marginal Bone Loss: Can a Thin Layer of Zinc Oxide Cement Provide Sufficient Retention?

    PubMed

    Frisch, Eberhard; Ratka-Krüger, Petra; Weigl, Paul; Woelber, Johan

    2016-01-01

    This report describes the use of laboratory-fabricated crown intaglio replicas for extraorally prepared cementation of fixed restorations to implants. This technique minimizes excess cement and may therefore reduce the risk of cement-related marginal peri-implant bone loss. It is unclear whether the remaining thin layer of luting agent provides sufficient retention if low-adhesive zinc oxide (ZnO) cement is used. In 85 consecutive patients, 113 single crowns were cemented to implants using extraoral cementation technique (ECT) and ZnO cement. All patients were followed for 6 months and investigated for decementation. Seven events of decementation (incidence: 6.19%) were found in 7 patients (8.24%). ECT may represent a viable cementation technique for implant-supported single crowns, even using low-adhesion cements.

  8. Extraoral Cementation Technique to Minimize Cement-Associated Peri-implant Marginal Bone Loss: Can a Thin Layer of Zinc Oxide Cement Provide Sufficient Retention?

    PubMed

    Frisch, Eberhard; Ratka-Krüger, Petra; Weigl, Paul; Woelber, Johan

    2016-01-01

    This report describes the use of laboratory-fabricated crown intaglio replicas for extraorally prepared cementation of fixed restorations to implants. This technique minimizes excess cement and may therefore reduce the risk of cement-related marginal peri-implant bone loss. It is unclear whether the remaining thin layer of luting agent provides sufficient retention if low-adhesive zinc oxide (ZnO) cement is used. In 85 consecutive patients, 113 single crowns were cemented to implants using extraoral cementation technique (ECT) and ZnO cement. All patients were followed for 6 months and investigated for decementation. Seven events of decementation (incidence: 6.19%) were found in 7 patients (8.24%). ECT may represent a viable cementation technique for implant-supported single crowns, even using low-adhesion cements. PMID:27479343

  9. Beyond cochlear implants: awakening the deafened brain.

    PubMed

    Moore, David R; Shannon, Robert V

    2009-06-01

    Cochlear implants have provided hearing to more than 120,000 deaf people. Recent surgical developments include direct electrical stimulation of the brain, bilateral implants and implantation in children less than 1 year old. However, research is beginning to refocus on the role of the brain in providing benefits to implant users. The auditory system is able to use the highly impoverished input provided by implants to interpret speech, but this only works well in those who have developed language before their deafness or in those who receive their implant at a very young age. We discuss recent evidence suggesting that developing the ability of the brain to learn how to use an implant may be as important as further improvements of the implant technology. PMID:19471266

  10. Speech Understanding with a New Implant Technology: A Comparative Study with a New Nonskin Penetrating Baha System

    PubMed Central

    Caversaccio, Marco

    2014-01-01

    Objective. To compare hearing and speech understanding between a new, nonskin penetrating Baha system (Baha Attract) to the current Baha system using a skin-penetrating abutment. Methods. Hearing and speech understanding were measured in 16 experienced Baha users. The transmission path via the abutment was compared to a simulated Baha Attract transmission path by attaching the implantable magnet to the abutment and then by adding a sample of artificial skin and the external parts of the Baha Attract system. Four different measurements were performed: bone conduction thresholds directly through the sound processor (BC Direct), aided sound field thresholds, aided speech understanding in quiet, and aided speech understanding in noise. Results. The simulated Baha Attract transmission path introduced an attenuation starting from approximately 5 dB at 1000 Hz, increasing to 20–25 dB above 6000 Hz. However, aided sound field threshold shows smaller differences and aided speech understanding in quiet and in noise does not differ significantly between the two transmission paths. Conclusion. The Baha Attract system transmission path introduces predominately high frequency attenuation. This attenuation can be partially compensated by adequate fitting of the speech processor. No significant decrease in speech understanding in either quiet or in noise was found. PMID:25140314

  11. A 3-D enlarged cell technique (ECT) for elastic wave modelling of a curved free surface

    NASA Astrophysics Data System (ADS)

    Wei, Songlin; Zhou, Jianyang; Zhuang, Mingwei; Liu, Qing Huo

    2016-09-01

    The conventional finite-difference time-domain (FDTD) method for elastic waves suffers from the staircasing error when applied to model a curved free surface because of its structured grid. In this work, an improved, stable and accurate 3-D FDTD method for elastic wave modelling on a curved free surface is developed based on the finite volume method and enlarged cell technique (ECT). To achieve a sufficiently accurate implementation, a finite volume scheme is applied to the curved free surface to remove the staircasing error; in the mean time, to achieve the same stability as the FDTD method without reducing the time step increment, the ECT is introduced to preserve the solution stability by enlarging small irregular cells into adjacent cells under the condition of conservation of force. This method is verified by several 3-D numerical examples. Results show that the method is stable at the Courant stability limit for a regular FDTD grid, and has much higher accuracy than the conventional FDTD method.

  12. A 3-D enlarged cell technique (ECT) for elastic wave modelling of a curved free surface

    NASA Astrophysics Data System (ADS)

    Wei, Songlin; Zhou, Jianyang; Zhuang, Mingwei; Liu, Qing Huo

    2016-07-01

    The conventional finite-difference time-domain (FDTD) method for elastic waves suffers from the staircasing error when applied to model a curved free surface because of its structured grid. In this work, an improved, stable and accurate 3-D FDTD method for elastic wave modelling on a curved free surface is developed based on the finite volume method and enlarged cell technique (ECT). To achieve a sufficiently accurate implementation, a finite volume scheme is applied to the curved free surface to remove the staircasing error; in the mean time, to achieve the same stability as the FDTD method without reducing the time step increment, the ECT is introduced to preserve the solution stability by enlarging small irregular cells into adjacent cells under the condition of conservation of force. This method is verified by several 3-D numerical examples. Results show that the method is stable at the Courant stability limit for a regular FDTD grid, and has much higher accuracy than the conventional FDTD method.

  13. Innovative regeneration technology to solve peri-implantitis by Er:YAG laser based on the microbiologic diagnosis: a case series.

    PubMed

    Yoshino, Toshiaki; Yamamoto, Atsuhiko; Ono, Yoshihiro

    2015-01-01

    Peri-implantitis is an emerging problem, and corrective therapy requires a method for decontaminating the complex surface structure of the implant body and sterilizing the surrounding tissue. The erbium:yttrium-aluminum-garnet (Er:YAG) laser has proven to effectively allow tissue to regenerate when used for peri-implantitis. The power of the Er:YAG laser is absorbed by a water molecule; therefore, its target neither rises in temperature nor carbonizes. An antibacterial remedy based on the bacteriologic diagnosis, followed by debridement and sterilization of the implant surface and peri-implant tissues by Er:YAG laser is efficacious for peri-implantitis treatment. The aim of this report was to present the effectiveness of the Er:YAG laser for peri-implant bone regeneration. This case series of two patients showed that antibiotic therapy reduced the bacterial amount from the peri-implantitis sites significantly and that Er:YAG laser therapy, along with the bone augmentation, enhanced bone regeneration in the peri-implant bony defects.

  14. Feasibility and safety of electrochemotherapy (ECT) in the pancreas: a pre-clinical investigation

    PubMed Central

    Girelli, Roberto; Prejanò, Simona; Cataldo, Ivana; Corbo, Vincenzo; Martini, Lucia; Scarpa, Aldo; Claudio, Bassi

    2015-01-01

    Background. Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease generally refractory to standard chemotherapeutic agents; therefore improvements in anticancer therapies are mandatory. A major determinant of therapeutic resistance in PDAC is the poor drug delivery to neoplastic cells, mainly due to an extensive fibrotic reaction. Electroporation can be used in vivo to increase cancer cells’ local uptake of chemotherapeutics (electrochemotherapy, ECT), thus leading to an enhanced tumour response rate. In the present study, we evaluated the in vivo effects of reversible electroporation in normal pancreas in a rabbit experimental model. We also tested the effect of electroporation on pancreatic cancer cell lines in order to evaluate their increased sensitivity to chemotherapeutic agents. Materials and methods. The application in vivo of the European Standard Operating Procedure of Electrochemotherapy (ESOPE) pulse protocol (1000 V/cm, 8 pulses, 100 μs, 5 KHz) was tested on the pancreas of normal New Zealand White Rabbits and short and long-term toxicity were assessed. PANC1 and MiaPaCa2 cell lines were tested for in vitro electrochemotherapy experiments with and without electroporation. Levels of cell permeabilization were determined by flow cytometry, whereas cell viability and drug (cisplatin and bleomycin) sensitivity of pulsed cells were measured by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Results. In healthy rabbits, neither systemic nor local toxic effects due to the electroporation procedure were observed, demonstrating the safety of the optimized electric parameters in the treatment of the pancreas in vivo. In parallel, we established an optimized protocol for ECT in vitro that determined an enhanced anti-cancer effect of bleomycin and cisplatin with respect to treatment without electroporation. Conclusions. Our data suggest that electroporation is a safe procedure in the treatment of PDAC

  15. Cochlear Implants

    MedlinePlus

    ... outside of the body, behind the ear. A second part is surgically placed under the skin. An implant does not restore normal hearing. It can help a person understand speech. Children and adults can benefit from them. National Institute on Deafness and Other Communication Disorders

  16. Dealing with moral dilemma raised by adaptive preferences in health technology assessment: the example of growth hormones and bilateral cochlear implants.

    PubMed

    Thébaut, Clémence

    2013-12-01

    The aim of this article is to assess dilemma raised by adaptive preferences in the economic evaluation of growth hormone (GH) treatment for non-GH-deficient short children, and of bilateral cochlear implants for deaf children. Early implementation of both technologies and their irreversible consequences increase the potential conflicts faced by the assessors of health-related quality of life (HRQoL) states (on behalf of patients) who could be interviewed (parents, individuals with an experience of the same disability, or representative samples of the general public). Indeed, assessors' preferences may be influenced by their own situation and they are likely to vary according to age and the experience of disability. Three options are put forward which aim to resolve these moral dilemma and help economists make methodological choices that cannot be avoided in order to carry out this assessment. They are grounded on three specific egalitarian theories of social justice. The main contribution of this article is to show that a dialogue between ethics and economics, prior to an assessment, makes it possible to redefine the choice of effectiveness criteria (subjective well-being, capabilities or social outcomes), the choice of perspective (patients or the able-bodied), as well as the scope of assessment (medical and non-medical care). PMID:24355476

  17. Purinergic Signaling in Early Inflammatory Events of the Foreign Body Response: Modulating Extracellular ATP as an Enabling Technology for Engineered Implants and Tissues

    PubMed Central

    Fann, Stephen A.; Yost, Michael J.

    2014-01-01

    Purinergic signaling is a ubiquitous and vital aspect of mammalian biology in which purines—mainly adenosine triphosphate (ATP)—are released from cells through loss of membrane integrity (cell death), exocytosis, or transport/diffusion across membrane channels, and exert paracrine or autocrine signaling effects through three subclasses of well-characterized receptors: the P1 adenosine receptors, the P2X ionotropic nucleotide receptors, and the P2Y metabotropic receptors. ATP and its metabolites are released by damaged and stressed cells in injured tissues. The early events of wound healing, hemostasis, and inflammation are highly regulated by these signals through activation of purinergic receptors on platelets and neutrophils. Recent data have demonstrated that ATP signaling is of particular importance to targeting leukocytes to sites of injury. This is particularly relevant to the subject of implanted medical devices, engineered tissues, and grafts as all these technologies elicit a wound healing response with varying degrees of encapsulation, rejection, extrusion, or destruction of the tissue or device. Here, we review the biology of purinergic signaling and focus on ATP release and response mechanisms that pertain to the early inflammatory phase of wound healing. Finally, therapeutic options are explored, including a new class of peptidomimetic drugs based on the ATP-conductive channel connexin43. PMID:24279914

  18. Dealing with moral dilemma raised by adaptive preferences in health technology assessment: the example of growth hormones and bilateral cochlear implants.

    PubMed

    Thébaut, Clémence

    2013-12-01

    The aim of this article is to assess dilemma raised by adaptive preferences in the economic evaluation of growth hormone (GH) treatment for non-GH-deficient short children, and of bilateral cochlear implants for deaf children. Early implementation of both technologies and their irreversible consequences increase the potential conflicts faced by the assessors of health-related quality of life (HRQoL) states (on behalf of patients) who could be interviewed (parents, individuals with an experience of the same disability, or representative samples of the general public). Indeed, assessors' preferences may be influenced by their own situation and they are likely to vary according to age and the experience of disability. Three options are put forward which aim to resolve these moral dilemma and help economists make methodological choices that cannot be avoided in order to carry out this assessment. They are grounded on three specific egalitarian theories of social justice. The main contribution of this article is to show that a dialogue between ethics and economics, prior to an assessment, makes it possible to redefine the choice of effectiveness criteria (subjective well-being, capabilities or social outcomes), the choice of perspective (patients or the able-bodied), as well as the scope of assessment (medical and non-medical care).

  19. Sub-2y node NAND flash characteristics using spot beam technology for low energy, high tilt implant for n-poly doping

    NASA Astrophysics Data System (ADS)

    Ryu, Chong-Il; Lee, Sangsun; Jeon, Young-Ho; Cheon, Youngil; Choi, Jin-Kwan; Yang, Young-Ho; Lee, Kyung-Won; Hong, Rympyo; Yoon, Jong-Yoon; Reece, Ron; Rubin, Leonard M.

    2012-11-01

    Reduction of polysilicon sheet resistivity and polysilicon depletion ratio (PDR) are two major challenges for improving the memory cell characteristics of sub-20 nm NAND Flash devices. High phosphorus doses are implanted into in situ doped polysilicon floating gates to improve PDR, but phosphorus concentrations that are too high can degrade cell characteristics by increasing trapped charge in the TNOX(Tunnel Oxide). It is also important to prevent the bending of narrow polysilicon lines during floating gate implantation. We explored various conditions of low energy, high tilt phosphorus implants for floating gate doping using a spot beam high current implanter. The optimal concentration of implant energy, tilt angle, and thermal annealing has been shown to improve PDR and floating gate TOP CD control.

  20. Computer implants and death.

    PubMed

    Gert, Bernard

    2009-01-01

    Although a patient whose whole brain has ceased to function may have his heart, lungs, and other organs continue to function if they are connected to the appropriate machines, the patient is still dead and the machines can be disconnected. In the future, nanotechnology, or other technology, may allow putting implants in the brainstem that can keep a patient's heart, lungs and other organs functioning, even though the whole natural brain has ceased to function. It would be useful to consider how this technology might affect the criterion of death before it is actually available.

  1. Pan-European Grading Scales: Lessons from National Systems and the ECTS. The Bologna Process: Retrospect and Prospects

    ERIC Educational Resources Information Center

    Karran, Terence

    2005-01-01

    This article assesses the impact of the Bologna Process on the grading schemes of EU member countries. In light of some problems regarding the implementation of the European Credit Transfer system (ECTS), the author proposes further reforms and offers some elements of a unified grading system for European higher education. The author explores the…

  2. Computerized implant-dentistry: Advances toward automation.

    PubMed

    Gulati, Minkle; Anand, Vishal; Salaria, Sanjeev Kumar; Jain, Nikil; Gupta, Shilpi

    2015-01-01

    Advancements in the field of implantology such as three-dimensional imaging, implant-planning software, computer-aided-design/computer-aided-manufacturing (CAD/CAM) technology, computer-guided, and navigated implant surgery have led to the computerization of implant-dentistry. This three-dimensional computer-generated implant-planning and surgery has not only enabled accurate preoperative evaluation of the anatomic limitations but has also facilitated preoperative planning of implant positions along with virtual implant placement and subsequently transferring the virtual treatment plans onto the surgical phase via static (guided) or dynamic (navigated) systems aided by CAD/CAM technology. Computerized-implant-dentistry being highly predictable and minimally invasive in nature has also allowed implant placement in patients with medical comorbidities (e.g. radiation therapy, blood dyscrasias), in patients with complex problems following a significant alteration of the bony anatomy as a result of benign or malignant pathology of the jaws or trauma and in patients with other physical and emotional problems. With significant achievements accomplished in the field of computerized implant-dentistry, attempts are now been made toward complete automation of implant-dentistry. PMID:25810585

  3. Computerized implant-dentistry: Advances toward automation

    PubMed Central

    Gulati, Minkle; Anand, Vishal; Salaria, Sanjeev Kumar; Jain, Nikil; Gupta, Shilpi

    2015-01-01

    Advancements in the field of implantology such as three-dimensional imaging, implant-planning software, computer-aided-design/computer-aided-manufacturing (CAD/CAM) technology, computer-guided, and navigated implant surgery have led to the computerization of implant-dentistry. This three-dimensional computer-generated implant-planning and surgery has not only enabled accurate preoperative evaluation of the anatomic limitations but has also facilitated preoperative planning of implant positions along with virtual implant placement and subsequently transferring the virtual treatment plans onto the surgical phase via static (guided) or dynamic (navigated) systems aided by CAD/CAM technology. Computerized-implant-dentistry being highly predictable and minimally invasive in nature has also allowed implant placement in patients with medical comorbidities (e.g. radiation therapy, blood dyscrasias), in patients with complex problems following a significant alteration of the bony anatomy as a result of benign or malignant pathology of the jaws or trauma and in patients with other physical and emotional problems. With significant achievements accomplished in the field of computerized implant-dentistry, attempts are now been made toward complete automation of implant-dentistry. PMID:25810585

  4. Short Implants: New Horizon in Implant Dentistry

    PubMed Central

    Gulati, Manisha; Garg, Meenu; Pathak, Chetan

    2016-01-01

    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. PMID:27790598

  5. [Evaluation of asymetric implants in breast cancer].

    PubMed

    Fitoussi, A; Couturaud, B; Laki, F; Alran, S; Salmon, R J

    2005-10-01

    Since more than twenty years, methods of breast reconstruction using implants have continued to evolve in order to improve their aesthetic results. Shapes and materials of these implants have also evolved to obtain contours similar to that of the natural opposite breast. Therefore it can be considered that the use of asymmetric implants is the last step in implant technology before using made to measure implants. Asymmetric implants allow obtaining different contours in harmony to the different breast shapes according to the side, left or right, of the reconstructed breast which maximise the naturalness of the result. Such implants have an axis directed towards the exterior and lower part of the chest wall, are wider than high with a thinner part on their inner edge and a concave rear side moulding the curves of the chest wall. In our own experience, we placed more than 500 asymmetric implants. When analysing retrospectively the medical records of 156 patients, no distinctive features were observed when compared to symmetric classic implants in easiness in the surgical procedure or in complications except a slightly higher rate of seroma formation. When compared to usual implants the main benefits of asymmetric implants are: to offer a wider breadth, to slope down gently on their upper and inner sides according to their concave rear side, and therefore to better match subtle curves of a normal breast. Moreover such contours allow a distribution of the volume which fit better to the usual natural breast configuration of patients who underwent surgery for breast carcinoma. At last, such implants are easy to place and a very low rate of secondary rotation has been observed. In summary, for all these reasons, asymmetric implants, can be considered to be the class one in the choice of implants for breast reconstruction after breast surgery. PMID:16198040

  6. [Non invasive intracranial hyperthermia with Electric Capacitive Transference -ECT- Intratumoral and cerebral thermometry results].

    PubMed

    Ley-Valle, A

    2003-02-01

    The aim of this work is to present the results of thermic increase obtained at the brain and intratumoral levels through a non invasive technique -Electric Capacitive Transference- (ECT), developed in 1985 by Indiba. A review of the literature does not provide any reference of cerebral and intratumoral thermometry in real time with a non invasive technique of intracranial hyperthermia. In the 8 studied patients, the increases of temperature in the brain, ranged between 0.7 and 1.5 degrees C in relation to the depth of the thermometric probe and the incidence angle of the external electrode. Between tumoral and perilesional brain tissues, thermic increase was 0.3 to 0.7 degrees C greater at tumoral level. The observation that in no case the surrounding brain tissue registered a temperature over 39.2 degrees C supports the harmlessness of the technique regarding the potential damage to healthy brain tissue and seems to confirm previous data obtained in anatomopathological studies in animal experimentation performed in 1990, which showed an absence of lesions in tissues and organs. The greater and somewhat more prolonged thermic increase observed at tumoral level has been called the "greenhouse effect".

  7. Common Prosthetic Implant Complications in Fixed Restorations.

    PubMed

    Link-Bindo, Elyce E; Soltys, James; Donatelli, David; Cavanaugh, Richard

    2016-07-01

    Many clinicians consider implants to be one of the most important innovations in dental care. Even so, over the past 40 years of implant dentistry, complications have been a constant struggle for restorative dentists, surgeons, and patients alike. Implant-related problems can be particularly challenging and frustrating, especially given that an implant is thought to be a "lifetime" solution expected to yield minimal difficulties. This, however, is not necessarily the case with prosthetic restorations. With innovations in implant technology continuing to rapidly advance, maintaining knowledge of all the latest developments can be challenging for clinicians. The purpose of this article is to provide a basic understanding of the treatment, management, and prevention of common prosthetic and technical implant complications seen in the office of a restorative dentist. PMID:27548395

  8. Orbital implants: potential new directions.

    PubMed

    Hicks, Celia R; Morrison, David; Lou, Xia; Crawford, Geoffrey J; Gadjatsy, Adam; Constable, Ian J

    2006-11-01

    This article reviews orbital implants used to replace an eye after enucleation or evisceration. Advantages of implant placement are described, with discussion of implant and wrap material, and design features that affect clinical outcomes. Implants may be porous or nonporous, pegged for linkage with a cosmetic shell or unpegged, and may be wrapped with a covering material or tissue or unwrapped. Device shape, volume and material qualities affect tissue tolerance and the risk of exposure or extrusion. Limitations of currently available devices are discussed, with factors affecting surgeon and patient choice. Ideally, a device should be easy to insert, avoid the need for wrapping or adjunctive tissues, be light, biointegratable, comfortable after implantation and provide satisfactory orbital volume replacement, movement and cosmesis without requiring further surgery or pegging. This review briefly discusses developments in implant design and aspects of design that affect function, but is not a detailed clinical review; rather, it aims to stimulate thought on optimal design and discusses recent developments. Novel technology in the form of a prototype device with a soft, biointegratable anterior surface is described as an example of newer approaches.

  9. Nanostructured Surfaces of Dental Implants

    PubMed Central

    Bressan, Eriberto; Sbricoli, Luca; Guazzo, Riccardo; Tocco, Ilaria; Roman, Marco; Vindigni, Vincenzo; Stellini, Edoardo; Gardin, Chiara; Ferroni, Letizia; Sivolella, Stefano; Zavan, Barbara

    2013-01-01

    The structural and functional fusion of the surface of the dental implant with the surrounding bone (osseointegration) is crucial for the short and long term outcome of the device. In recent years, the enhancement of bone formation at the bone-implant interface has been achieved through the modulation of osteoblasts adhesion and spreading, induced by structural modifications of the implant surface, particularly at the nanoscale level. In this context, traditional chemical and physical processes find new applications to achieve the best dental implant technology. This review provides an overview of the most common manufacture techniques and the related cells-surface interactions and modulation. A Medline and a hand search were conducted to identify studies concerning nanostructuration of implant surface and their related biological interaction. In this paper, we stressed the importance of the modifications on dental implant surfaces at the nanometric level. Nowadays, there is still little evidence of the long-term benefits of nanofeatures, as the promising results achieved in vitro and in animals have still to be confirmed in humans. However, the increasing interest in nanotechnology is undoubted and more research is going to be published in the coming years. PMID:23344062

  10. Capacitive Feedthroughs for Medical Implants.

    PubMed

    Grob, Sven; Tass, Peter A; Hauptmann, Christian

    2016-01-01

    Important technological advances in the last decades paved the road to a great success story for electrically stimulating medical implants, including cochlear implants or implants for deep brain stimulation. However, there are still many challenges in reducing side effects and improving functionality and comfort for the patient. Two of the main challenges are the wish for smaller implants on one hand, and the demand for more stimulation channels on the other hand. But these two aims lead to a conflict of interests. This paper presents a novel design for an electrical feedthrough, the so called capacitive feedthrough, which allows both reducing the size, and increasing the number of included channels. Capacitive feedthroughs combine the functionality of a coupling capacitor and an electrical feedthrough within one and the same structure. The paper also discusses the progress and the challenges of the first produced demonstrators. The concept bears a high potential in improving current feedthrough technology, and could be applied on all kinds of electrical medical implants, even if its implementation might be challenging.

  11. Capacitive Feedthroughs for Medical Implants.

    PubMed

    Grob, Sven; Tass, Peter A; Hauptmann, Christian

    2016-01-01

    Important technological advances in the last decades paved the road to a great success story for electrically stimulating medical implants, including cochlear implants or implants for deep brain stimulation. However, there are still many challenges in reducing side effects and improving functionality and comfort for the patient. Two of the main challenges are the wish for smaller implants on one hand, and the demand for more stimulation channels on the other hand. But these two aims lead to a conflict of interests. This paper presents a novel design for an electrical feedthrough, the so called capacitive feedthrough, which allows both reducing the size, and increasing the number of included channels. Capacitive feedthroughs combine the functionality of a coupling capacitor and an electrical feedthrough within one and the same structure. The paper also discusses the progress and the challenges of the first produced demonstrators. The concept bears a high potential in improving current feedthrough technology, and could be applied on all kinds of electrical medical implants, even if its implementation might be challenging. PMID:27660602

  12. Capacitive Feedthroughs for Medical Implants

    PubMed Central

    Grob, Sven; Tass, Peter A.; Hauptmann, Christian

    2016-01-01

    Important technological advances in the last decades paved the road to a great success story for electrically stimulating medical implants, including cochlear implants or implants for deep brain stimulation. However, there are still many challenges in reducing side effects and improving functionality and comfort for the patient. Two of the main challenges are the wish for smaller implants on one hand, and the demand for more stimulation channels on the other hand. But these two aims lead to a conflict of interests. This paper presents a novel design for an electrical feedthrough, the so called capacitive feedthrough, which allows both reducing the size, and increasing the number of included channels. Capacitive feedthroughs combine the functionality of a coupling capacitor and an electrical feedthrough within one and the same structure. The paper also discusses the progress and the challenges of the first produced demonstrators. The concept bears a high potential in improving current feedthrough technology, and could be applied on all kinds of electrical medical implants, even if its implementation might be challenging. PMID:27660602

  13. Capacitive Feedthroughs for Medical Implants

    PubMed Central

    Grob, Sven; Tass, Peter A.; Hauptmann, Christian

    2016-01-01

    Important technological advances in the last decades paved the road to a great success story for electrically stimulating medical implants, including cochlear implants or implants for deep brain stimulation. However, there are still many challenges in reducing side effects and improving functionality and comfort for the patient. Two of the main challenges are the wish for smaller implants on one hand, and the demand for more stimulation channels on the other hand. But these two aims lead to a conflict of interests. This paper presents a novel design for an electrical feedthrough, the so called capacitive feedthrough, which allows both reducing the size, and increasing the number of included channels. Capacitive feedthroughs combine the functionality of a coupling capacitor and an electrical feedthrough within one and the same structure. The paper also discusses the progress and the challenges of the first produced demonstrators. The concept bears a high potential in improving current feedthrough technology, and could be applied on all kinds of electrical medical implants, even if its implementation might be challenging.

  14. ECT imaging with Tc(V)-99m dimercaptosuccinic acid useful to detect lung metastases of osteosarcoma

    SciTech Connect

    Ohta, H.; Ishii, M.; Yoshizumi, M.; Endo, K.; Fujita, T.; Nakajima, T.; Sakahara, H.; Torizuka, K.; Kotoura, Y.; Yokoyama, A.

    1985-01-01

    ECT imaging, using Tc(V)-99m dimercaptosuccinic acid (Tc(V)-DMS) was performed in two patients with lung metastasis of osteosarcoma, and the results were compared with those of CT scan. Clear accumulation of Tc(V)-DMS was recognized in all cases in the same area that CT scans demonstrated. Tc(V)-DMS was labeled under optimal pH 8, had very low SnCl/sub 2/ concentrations, an equilibrium between a stable form and a dissociated form of anion TcO/sub 4/(3-) structurally similar to PO/sub 4/(3-), and was postulated for tumor uptake. Considering this proposed mechanism for Tc(V)-DMS uptake by tumor cells, ECT imaging using this tracer could be of use in the early detection of lung metastasis of osteosarcoma.

  15. An ECT/ERT dual-modality sensor for oil-water two-phase flow measurement

    SciTech Connect

    Wang, Pitao; Wang, Huaxiang; Sun, Benyuan; Cui, Ziqiang; Huang, Wenrui

    2014-04-11

    This paper presents a new sensor for ECT/ERT dual-modality system which can simultaneously obtain the permittivity and conductivity of the materials in the pipeline. Quasi-static electromagnetic fields are produced by the inner electrodes array sensor of electrical capacitance tomography (ECT) system. The results of simulation show that the data of permittivity and conductivity can be simultaneously obtained from the same measurement electrode and the fusion of two kinds of data may improve the quality of the reconstructed images. For uniform oil-water mixtures, the performance of designed dual-modality sensor for measuring the various oil fractions has been tested on representative data and the results of experiments show that the designed sensor broadens the measurement range compared to single modality.

  16. Identification and characterization of ectoine biosynthesis genes and heterologous expression of the ectABC gene cluster from Halomonas sp. QHL1, a moderately halophilic bacterium isolated from Qinghai Lake.

    PubMed

    Zhu, Derui; Liu, Jian; Han, Rui; Shen, Guoping; Long, Qifu; Wei, Xiaoxing; Liu, Deli

    2014-02-01

    The moderately halophilic bacterium Halomonas sp. QHL1 was identified as a member of the genus Halomonas by 16S rRNA gene sequencing. HPLC analysis showed that strain QHL1 synthesizes ectoine in its cytoplasm. The genes involved in the ectoine biosynthesis pathway were identified on the chromosome in the order ectABC. Subsequently, the ectB gene from this strain was amplified by PCR, and the entire ectABC gene cluster (3,580 bp) was cloned using genome walking. Analysis showed that the ectA (579 bp), ectB (1269 bp), and ectC (390 bp) genes were organized in a single transcriptional unit and were predicted to encode three peptides of 21.2 kDa, 46.4 kDa, and 14.7 kDa, respectively. Two putative promoters, a δ(70)-dependent promoter and a δ(38)-controlled promoter, as well as several conserved motifs with unknown function were identified. Individual ectA, ectB, and ectC genes, and the entire ectABC gene cluster were inserted into the expression plasmid pET-28a(+) to generate the recombinant plasmids pET-28a(+)-ectA, pET-28a(+)-ectB, pET-28a(+)-ectC and pET-28a(+)-ectABC, respectively. Heterologous expression of these proteins in Escherichia coli BL21 (DE3) was confirmed by SDS-PAGE. The recombinant E. coli strain BL21 (pET-28a (+)-ectABC) displayed a higher salt tolerance than native E. coli cells but produced far less ectoine than the wild-type QHL1 strain.

  17. Characterization of the Edge Crack Torsion (ECT) Test for Mode III Fracture Toughness Measurement of Laminated Composites

    NASA Technical Reports Server (NTRS)

    Ratcliffe, James G.

    2004-01-01

    The edge crack torsion (ECT) test is designed to initiate mode III delamination growth in composite laminates. An ECT specimen is a rectangular laminate, containing an edge delamination at the laminate mid-plane. Torsion load is applied to the specimens, resulting in relative transverse shear sliding of the delaminated faces. The test data reduction schemes are intended to yield initiation values of critical mode III strain energy release rate, G(sub IIIc), that are constant with delamination length. The test has undergone several design changes during its development. The objective of this paper was to determine the suitability of the current ECT test design as a mode III fracture test. To this end, ECT tests were conducted on specimens manufactured from IM7/8552 and specimens made from S2/8552 tape laminates. Several specimens, each with different delamination lengths are tested. Detailed, three-dimensional finite element analyses of the specimens were performed. The analysis results were used to calculate the distribution of mode I, mode II, and mode III strain energy release rate along the delamination front. The results indicated that mode III-dominated delamination growth would be initiated from the specimen center. However, in specimens of both material types, the measured values of G(sub IIIc) exhibited significant dependence on delamination length. Furthermore, there was a large amount of scatter in the data. Load-displacement response of the specimens exhibited significant deviation from linearity before specimen failure. X-radiographs of a sample of specimens revealed that damage was initiated in the specimens prior to failure. Further inspection of the failure surfaces is required to identify the damage and determine that mode III delamination is initiated in the specimens.

  18. Characterization of the Edge Crack Torsion (ECT) Test for Mode III Fracture Toughness Measurement of Laminated Composites

    NASA Technical Reports Server (NTRS)

    Ratcliffe, James G.

    2004-01-01

    The edge crack torsion (ECT) test is designed to initiate mode III delamination growth in composite laminates. The test has undergone several design changes during its development. The objective of this paper was to determine the suitability of the current ECT test design a mode III fracture test. To this end, ECT tests were conducted on specimens manufactured from IM7/8552 and S2/8552 tape laminates. Three-dimensional finite element analyses were performed. The analysis results were used to calculate the distribution of mode I, mode II, and mode III strain energy release rate along the delamination front. The results indicated that mode IIIdominated delamination growth would be initiated from the specimen center. However, in specimens of both material types, the measured values of GIIIc exhibited significant dependence on delamination length. Load-displacement response of the specimens exhibited significant deviation from linearity before specimen failure. X-radiographs of a sample of specimens revealed that damage was initiated in the specimens prior to failure. Further inspection of the failure surfaces is required to identify the damage and determine that mode III delamination is initiated in the specimens.

  19. Production and characterization of ectoine by Marinococcus sp. ECT1 isolated from a high-salinity environment.

    PubMed

    Wei, Yu-Hong; Yuan, Fang-Wei; Chen, Wei-Chuan; Chen, Shan-Yu

    2011-03-01

    A halophilic bacterium isolated from a salt environment in southern Taiwan was identified as a Marinococcus sp. ECT1. This bacterium could synthesize and accumulate intracellular ectoine as a compatible solute capable of resisting osmotic stress in a hyper-osmotic environment. This study also developed a semi-synthesized medium (YAMS medium), capable of facilitating the growth of this Marinococcus sp. ECT1 with 600 mg/L crude ectoine production. Moreover, Marinococcus sp. ECT1 was grown on YAMS medium containing different initial yeast extract concentrations (C(YE)) (0 to 60 g/L) to demonstrate how C(YE) affects crude ectoine production. While the maximum cell concentration was increased by 23-fold when the C(YE) was 40 g/L, the maximum crude ectoine production reached 2.5 g/L when C(YE) was 40 g/L. In addition to demonstrating the success of the fermentation strategy of ectoine in increasing the production and production yield, experimental results further demonstrated that the fermentation medium of ectoine is highly promising for commercialization. Furthermore, the molecular weight and chemical structure of ectoine were identified and characterized by FAB-MS and (1)H-NMR.

  20. Historical development of active middle ear implants.

    PubMed

    Carlson, Matthew L; Pelosi, Stanley; Haynes, David S

    2014-12-01

    Active middle ear implants (AMEIs) are sophisticated technologies designed to overcome many of the shortcomings of conventional hearing aids, including feedback, distortion, and occlusion effect. Three AMEIs are currently approved by the US Food and Drug Administration for implantation in patients with sensorineural hearing loss. In this article, the history of AMEI technologies is reviewed, individual component development is outlined, past and current implant systems are described, and design and implementation successes and dead ends are highlighted. Past and ongoing challenges facing AMEI development are reviewed.

  1. GlnR-Mediated Regulation of ectABCD Transcription Expands the Role of the GlnR Regulon to Osmotic Stress Management

    PubMed Central

    Shao, ZhiHui; Deng, WanXin; Li, ShiYuan; He, JuanMei; Ren, ShuangXi; Huang, WeiRen; Lu, YinHua; Zhao, GuoPing

    2015-01-01

    ABSTRACT Ectoine and hydroxyectoine are excellent compatible solutes for bacteria to deal with environmental osmotic stress and temperature damages. The biosynthesis cluster of ectoine and hydroxyectoine is widespread among microorganisms, and its expression is activated by high salinity and temperature changes. So far, little is known about the mechanism of the regulation of the transcription of ect genes and only two MarR family regulators (EctR1 in methylobacteria and the EctR1-related regulator CosR in Vibrio cholerae) have been found to negatively regulate the expression of ect genes. Here, we characterize GlnR, the global regulator for nitrogen metabolism in actinomycetes, as a negative regulator for the transcription of ectoine/hydroxyectoine biosynthetic genes (ect operon) in Streptomyces coelicolor. The physiological role of this transcriptional repression by GlnR is proposed to protect the intracellular glutamate pool, which acts as a key nitrogen donor for both the nitrogen metabolism and the ectoine/hydroxyectoine biosynthesis. IMPORTANCE High salinity is deleterious, and cells must evolve sophisticated mechanisms to cope with this osmotic stress. Although production of ectoine and hydroxyectoine is one of the most frequently adopted strategies, the in-depth mechanism of regulation of their biosynthesis is less understood. So far, only two MarR family negative regulators, EctR1 and CosR, have been identified in methylobacteria and Vibrio, respectively. Here, our work demonstrates that GlnR, the global regulator for nitrogen metabolism, is a negative transcriptional regulator for ect genes in Streptomyces coelicolor. Moreover, a close relationship is found between nitrogen metabolism and osmotic resistance, and GlnR-mediated regulation of ect transcription is proposed to protect the intracellular glutamate pool. Meanwhile, the work reveals the multiple roles of GlnR in bacterial physiology. PMID:26170409

  2. Oral Implant Imaging: A Review

    PubMed Central

    GUPTA, Sarika; PATIL, Neelkant; SOLANKI, Jitender; SINGH, Ravinder; LALLER, Sanjeev

    2015-01-01

    Selecting an appropriate implant imaging technique has become a challenging task since the advent of advanced imaging modalities, and many of these are used for implant imaging. On imaging, the modality should not only consider the anatomy but should also provide dimensional accuracy. Many dentists use the conventional method, mostly orthopantograph (OPG), in their routine practice of implant placement. However, because of the drawbacks associated with OPG, higher technologies, such as computed tomography (CT) and cone beam computed tomography (CBCT), are better accepted. These help improve image sharpness and reduce distortion. These techniques are not used widely due to the cost effect. Therefore, to decide on the type of imaging technique, all associated advantages and disadvantages should be considered, which will be broadly discussed in this review. PMID:26715891

  3. Expansion of a Predoctoral Surgical Implant Selective for Dental Students.

    PubMed

    Seitz, Stefanie D; Zimmermann, Richard L; Hendricson, William D

    2016-03-01

    Historically, predoctoral dental education programs have focused on the restoration of implants in the clinical environment; however, given the increase in dental implant therapy being performed by general dentists, the need to incorporate surgical implant training is becoming evident. This article describes a predoctoral surgical implant selective at the University of Texas Health Science Center at San Antonio and its evolution across five years to include emerging techniques and technology to enhance students' understanding of dental implant therapy, both surgical and restorative. From virtual implant planning and guided surgery to intra-oral scanning of implants for custom abutments and restorations, students obtained first-hand experiences with a wide spectrum of aspects of implant therapy. The results of anonymous surveys completed by 2014-15 students before and after the year-long selective regarding their impression of the program are also discussed. PMID:26933108

  4. Immediate postextraction implant placement using plasma rich in growth factors technology in maxillary premolar region: a new strategy for soft tissue management.

    PubMed

    Rosano, Gabriele; Taschieri, Silvio; Del Fabbro, Massimo

    2013-02-01

    Achieving an excellent aesthetic outcome in postextraction dental implant placement in the anterior maxilla is a challenging procedure for clinicians. In fact, there is an increased risk for soft tissue recession at the facial aspect which may require supplementary connective tissue grafts to accomplish the final aesthetic result. The aim of this case report is to describe a regenerative technique using autologous plasma rich in growth factors fibrin plug for preservation of soft tissue architecture around an implant immediately placed into an extraction site in the anterior maxilla. Such a procedure allowed for guided bone regeneration without the need for vertical releasing incisions and primary healing, thus showing a pleasant gingival contour at the facial aspect after a single stage surgery. Integrating this technique into common practice could provide important benefits for the patients regarding aesthetics, without any risk of infection or transmission of diseases.

  5. Recurrent implantation failure: a comprehensive review.

    PubMed

    Zohni, Khaled M; Gat, Itai; Librach, Clifford

    2016-12-01

    Successful pregnancy involves a synchronized, coordinated cross-talk between an embryo capable of implanting, and an endometrium enabling implantation. Recurrent implantation failure (RIF) refers to unsuccessful implantation after repeated transfers of morphologically good quality embryos into a normal uterus. The etiology for RIF can be attributed to the embryo itself, the mother or, in some cases, both. Despite extensive research on underlying causes for RIF, our understanding of this condition is still limited. With the evolving molecular technologies, efforts are focused on studying the implantation process itself, including the molecular aspects of endometrial-embryonic interactions, normal human embryonic development, and preimplantation genetic evaluation. This knowledge will pave the way toward new diagnostic and therapeutic strategies for RIF. In this article, we present a comprehensive review of our current knowledge on this topic. PMID:26982235

  6. Trends in total knee arthroplasty implant utilization.

    PubMed

    Nguyen, Long-Co L; Lehil, Mandeep S; Bozic, Kevin J

    2015-05-01

    The incidence of total knee arthroplasty (TKA) has increased alongside our knowledge of knee physiology, kinematics, and technology resulting in an evolution of TKA implants. This study examines the trends in TKA implant utilization. Data was extracted from The Orthopedic Research Network to evaluate trends in level of constraint, fixed vs. mobile bearing, fixation, and type of polyethylene in primary TKAs. In 2012, 88% used cemented femoral and tibial implants, and 96% involved patellar resurfacing. 38% of implants were cruciate retaining, 53% posterior stabilized or condylar stabilized, 3% constrained. 91% were fixed-bearing, 7% mobile-bearing. 52% of tibial inserts were HXLPE. TKA implant trends demonstrate a preference for cemented femoral and tibial components, patellar resurfacing, fixed-bearing constructs, metal-backed tibial components, patellar resurfacing, and increased usage of HXLPE liners. PMID:25613663

  7. 30 GHz monolithic balanced mixers using an ion-implanted FET-compatible 3-inch GaAs wafer process technology

    NASA Technical Reports Server (NTRS)

    Bauhahn, P.; Contolatis, A.; Sokolov, V.; Chao, C.

    1986-01-01

    An all ion-implanted Schottky barrier mixer diode which has a cutoff frequency greater than 1000 GHz has been developed. This new device is planar and FET-compatible and employs a projection lithography 3-inch wafer process. A Ka-band monolithic balanced mixer based on this device has been designed, fabricated and tested. A conversion loss of 8 dB has been measured with a LO drive of 10 dBm at 30 GHz.

  8. Cochlear implants: selection criteria and shifting borders.

    PubMed

    Lenarz, T

    1998-01-01

    Cochlear implants have proven to be effective and reliable in postlingually deaf adults. This is also true for congenitally deaf and perilingually deaf children up to the age of six years. Due to the increasing experience, the improvement of implant technology and the proven reliability the selection criteria are broadened with shifting borders. The main extensions are related to age, additional handicaps, residual hearing and special etiologies of deafness. Increasing evidence shows that very early implantation results in better performance and better hearing and speech development. Near-normal language acquisition can be achieved in children implanted under the age of four. Additional handicaps do not automatically exclude a candidate from cochlear implantation. A case-to-case decision has to be made based on additional diagnostics and the experience of the implant centre. A list of suitable handicaps is provided. Severely hearing impaired patients may also be considered for cochlear implantation if their residual hearing provides no benefit for speech discrimination. The same holds true for children. Cochlear implantation in obliterated cochleae and inner ear malformation requires a special surgical technique and special electrode arrays. In this way even difficult cases can be managed with remarkable outcome. Over all, the selection criteria have been broadened with increasing experience and technological improvement. This development may continue and the borderline between hearing aids and cochlear implants will shift further towards severe hearing loss. However, the basis for success still remains good rehabilitation, a team approach and the willingness of the patient to undergo the whole process of cochlear implantation.

  9. Evaluation of the Edge Crack Torsion (ECT) Test for Mode 3 Interlaminar Fracture Toughness of Laminated Composites

    NASA Technical Reports Server (NTRS)

    Li, Jian; Lee, Edward W.; OBrien, T. Kevin; Lee, Shaw Ming

    1996-01-01

    An analytical and experimental investigation was carried out on G40-800/R6376 graphite epoxy laminates to evaluate the Edge Crack Torsion (ECT) test as a candidate for a standard Mode 3 interlaminar fracture toughness test for laminated composites. The ECT test consists of a (90/(+/- 45)(sub 3)/(+/- 45)(sub 3)/90))(sub s) laminate with a delamination introduced by a non-adhesive film at the mid-plane along one edge and loaded in a special fixture to create torsion along the length of the laminate. Dye penetrate enhanced X-radiograph of failed specimens revealed that the delamination initiated at the middle of the specimen length and propagated in a self similar manner along the laminate mid-plane. A three-dimensional finite element analysis was performed that indicated that a pure Mode 3 delamination exists at the middle of specimen length away from both ends. At the ends near the loading point a small Mode 2 component exists. However, the magnitude of this Mode 2 strain energy release rate at the loading point is small compared to the magnitude of Mode 3 component in the mid-section of the specimen. Hence, the ECT test yielded the desired Mode 3 delamination. The Mode 3 fracture toughness was obtained from a compliance calibration method and was in good agreement with the finite element results. Mode 2 End-Notched Flexure (ENF) tests and Mode 1 Double Cantilever Beam (DCB) tests were also performed for the same composite material. The Mode 1 fracture toughness was much smaller than both the Mode 2 and Mode 3 fracture toughness. The Mode 2 fracture toughness was found to be 75% of the Mode 3 fracture toughness.

  10. Fabricating specialised orthopaedic implants using additive manufacturing

    NASA Astrophysics Data System (ADS)

    Unwin, Paul

    2014-03-01

    It has been hypothesised that AM is ideal for patient specific orthopaedic implants such as those used in bone cancer treatment, that can rapidly build structures such as lattices for bone and tissues to in-grow, that would be impossible using current conventional subtractive manufacturing techniques. The aim of this study was to describe the adoption of AM (direct metal laser sintering and electron beam melting) into the design manufacturing and post-manufacturing processes and the early clinical use. Prior to the clinical use of AM implants, extensive metallurgical and mechanical testing of both laser and electron beam fabrications were undertaken. Concurrently, post-manufacturing processes evaluated included hipping, cleaning and coating treatments. The first clinical application of a titanium alloy mega-implant was undertaken in November 2010. A 3D model of the pelvic wing implant was designed from CT scans. Novel key features included extensive lattice structures at the bone interfaces and integral flanges to fix the implant to the bone. The pelvic device was implanted with the aid of navigation and to date the patient remains active. A further 18 patient specific mega-implants have now been implanted. The early use of this advanced manufacturing route for patient specific implants has been very encouraging enabling the engineer to produce more advanced and anatomical conforming implants. However, there are a new set of design, manufacturing and regulatory challenges that require addressing to permit this technique to be used more widely. This technology is changing the design and manufacturing paradigm for the fabrication of specialised orthopaedic implants.

  11. Implant success!!!.....simplified.

    PubMed

    Luthra, Kaushal K

    2009-01-01

    The endeavor towards life-like restoration has helped nurture new vistas in the art and science of implant dentistry. The protocol of "restoration-driven implant placement" ensures that the implant is an apical extension of the ideal future restoration and not the opposite. Meticulous pre-implant evaluation of soft and hard tissues, diagnostic cast and use of aesthetic wax-up and radiographic template combined with surgical template can simplify the intricate roadmap for appropriate implant treatment.By applying the harmony of artistic skill, scientific knowledge and clinical expertise, we can simply master the outstanding implant success in requisites of aesthetics, phonetics and function.

  12. RAPID MANUFACTURING SYSTEM OF ORTHOPEDIC IMPLANTS

    PubMed Central

    Relvas, Carlos; Reis, Joana; Potes, José Alberto Caeiro; Fonseca, Fernando Manuel Ferreira; Simões, José Antonio Oliveira

    2015-01-01

    This study, aimed the development of a methodology for rapid manufacture of orthopedic implants simultaneously with the surgical intervention, considering two potential applications in the fields of orthopedics: the manufacture of anatomically adapted implants and implants for bone loss replacement. This work innovation consists on the capitation of the in situ geometry of the implant by direct capture of the shape using an elastomeric material (polyvinylsiloxane) which allows fine detail and great accuracy of the geometry. After scanning the elastomeric specimen, the implant is obtained by machining using a CNC milling machine programmed with a dedicated CAD/CAM system. After sterilization, the implant is able to be placed on the patient. The concept was developed using low cost technology and commercially available. The system has been tested in an in vivo hip arthroplasty performed on a sheep. The time increase of surgery was 80 minutes being 40 minutes the time of implant manufacturing. The system developed has been tested and the goals defined of the study achieved enabling the rapid manufacture of an implant in a time period compatible with the surgery time. PMID:27004181

  13. Molecular mechanisms of membrane interaction at implantation.

    PubMed

    Davidson, Lien M; Coward, Kevin

    2016-03-01

    Successful pregnancy is dependent upon the implantation of a competent embryo into a receptive endometrium. Despite major advancement in our understanding of reproductive medicine over the last few decades, implantation failure still occurs in both normal pregnancies and those created artificially by assisted reproductive technology (ART). Consequently, there is significant interest in elucidating the etiology of implantation failure. The complex multistep process of implantation begins when the developing embryo first makes contact with the plasma membrane of epithelial cells within the uterine environment. However, although this biological interaction marks the beginning of a fundamental developmental process, our knowledge of the intricate physiological and molecular processes involved remains sparse. In this synopsis, we aim to provide an overview of our current understanding of the morphological changes which occur to the plasma membrane of the uterine endothelium, and the molecular mechanisms that control communication between the early embryo and the endometrium during implantation. A multitude of molecular factors have been implicated in this complex process, including endometrial integrins, extracellular matrix molecules, adhesion molecules, growth factors, and ion channels. We also explore the development of in vitro models for embryo implantation to help researchers investigate mechanisms which may underlie implantation failure. Understanding the precise molecular pathways associated with implantation failure could help us to generate new prognostic/diagnostic biomarkers, and may identify novel therapeutic targets. PMID:26969610

  14. RAPID MANUFACTURING SYSTEM OF ORTHOPEDIC IMPLANTS.

    PubMed

    Relvas, Carlos; Reis, Joana; Potes, José Alberto Caeiro; Fonseca, Fernando Manuel Ferreira; Simões, José Antonio Oliveira

    2009-01-01

    This study, aimed the development of a methodology for rapid manufacture of orthopedic implants simultaneously with the surgical intervention, considering two potential applications in the fields of orthopedics: the manufacture of anatomically adapted implants and implants for bone loss replacement. This work innovation consists on the capitation of the in situ geometry of the implant by direct capture of the shape using an elastomeric material (polyvinylsiloxane) which allows fine detail and great accuracy of the geometry. After scanning the elastomeric specimen, the implant is obtained by machining using a CNC milling machine programmed with a dedicated CAD/CAM system. After sterilization, the implant is able to be placed on the patient. The concept was developed using low cost technology and commercially available. The system has been tested in an in vivo hip arthroplasty performed on a sheep. The time increase of surgery was 80 minutes being 40 minutes the time of implant manufacturing. The system developed has been tested and the goals defined of the study achieved enabling the rapid manufacture of an implant in a time period compatible with the surgery time.

  15. [Biomaterials in cochlear implants].

    PubMed

    Stöver, T; Lenarz, T

    2009-05-01

    Cochlear implants (CI) represent the "gold standard" for the treatment of congenitally deaf children and postlingually deafened adults. Thus, cochlear implantation is a success story of new bionic prosthesis development. Owing to routine application of cochlear implants in adults but also in very young children (below the age of one), high demands are placed on the implants. This is especially true for biocompatibility aspects of surface materials of implant parts which are in contact with the human body. In addition, there are various mechanical requirements which certain components of the implants must fulfil, such as flexibility of the electrode array and mechanical resistance of the implant housing. Due to the close contact of the implant to the middle ear mucosa and because the electrode array is positioned in the perilymphatic space via cochleostomy, there is a potential risk of bacterial transferral along the electrode array into the cochlea. Various requirements that have to be fulfilled by cochlear implants, such as biocompatibility, electrode micromechanics, and although a very high level of technical standards has been carried out there is still demand for the improvement of implants as well as of the materials used for manufacturing, ultimately leading to increased implant performance. General considerations of material aspects related to cochlear implants as well as potential future perspectives of implant development will be discussed.

  16. Implantable hearing devices: the Ototronix MAXUM system.

    PubMed

    Pelosi, Stanley; Carlson, Matthew L; Glasscock, Michael E

    2014-12-01

    For many hearing-impaired individuals, the benefits of conventional amplification may be limited by acoustic feedback, occlusion effect, and/or ear discomfort. The MAXUM system and other implantable hearing devices have been developed as an option for patients who derive inadequate assistance from traditional HAs, but who are not yet candidates for cochlear implants. The MAXUM system is based on the SOUNDTEC Direct System technology, which has been shown to provide improved functional gain as well as reduced feedback and occlusion effect compared to hearing aids. This and other implantable hearing devices may have increasing importance as future aural rehabilitation options.

  17. Breast reconstruction - implants

    MedlinePlus

    ... visits, your surgeon injects a small amount of saline (salt water) through the valve into the expander. ... breast implants. Implants may be filled with either saline or a silicone gel. You may have another ...

  18. Transcatheter Aortic Valve Implantation.

    PubMed

    Malaisrie, S Chris; Iddriss, Adam; Flaherty, James D; Churyla, Andrei

    2016-05-01

    Severe aortic stenosis (AS) is a life-threatening condition when left untreated. Aortic valve replacement (AVR) is the gold standard treatment for the majority of patients; however, transcatheter aortic valve implantation/replacement (TAVI/TAVR) has emerged as the preferred treatment for high-risk or inoperable patients. The concept of transcatheter heart valves originated in the 1960s and has evolved into the current Edwards Sapien and Medtronic CoreValve platforms available for clinical use. Complications following TAVI, including cerebrovascular events, perivalvular regurgitation, vascular injury, and heart block have decreased with experience and evolving technology, such that ongoing trials studying TAVI in lower risk patients have become tenable. The multidisciplinary team involving the cardiac surgeon and cardiologist plays an essential role in patient selection, procedural conduct, and perioperative care.

  19. Implantable, multifunctional, bioresorbable optics

    PubMed Central

    Tao, Hu; Kainerstorfer, Jana M.; Siebert, Sean M.; Pritchard, Eleanor M.; Sassaroli, Angelo; Panilaitis, Bruce J. B.; Brenckle, Mark A.; Amsden, Jason J.; Levitt, Jonathan; Fantini, Sergio; Kaplan, David L.; Omenetto, Fiorenzo G.

    2012-01-01

    Advances in personalized medicine are symbiotic with the development of novel technologies for biomedical devices. We present an approach that combines enhanced imaging of malignancies, therapeutics, and feedback about therapeutics in a single implantable, biocompatible, and resorbable device. This confluence of form and function is accomplished by capitalizing on the unique properties of silk proteins as a mechanically robust, biocompatible, optically clear biomaterial matrix that can house, stabilize, and retain the function of therapeutic components. By developing a form of high-quality microstructured optical elements, improved imaging of malignancies and of treatment monitoring can be achieved. The results demonstrate a unique family of devices for in vitro and in vivo use that provide functional biomaterials with built-in optical signal and contrast enhancement, demonstrated here with simultaneous drug delivery and feedback about drug delivery with no adverse biological effects, all while slowly degrading to regenerate native tissue. PMID:23150544

  20. Implantable, multifunctional, bioresorbable optics.

    PubMed

    Tao, Hu; Kainerstorfer, Jana M; Siebert, Sean M; Pritchard, Eleanor M; Sassaroli, Angelo; Panilaitis, Bruce J B; Brenckle, Mark A; Amsden, Jason J; Levitt, Jonathan; Fantini, Sergio; Kaplan, David L; Omenetto, Fiorenzo G

    2012-11-27

    Advances in personalized medicine are symbiotic with the development of novel technologies for biomedical devices. We present an approach that combines enhanced imaging of malignancies, therapeutics, and feedback about therapeutics in a single implantable, biocompatible, and resorbable device. This confluence of form and function is accomplished by capitalizing on the unique properties of silk proteins as a mechanically robust, biocompatible, optically clear biomaterial matrix that can house, stabilize, and retain the function of therapeutic components. By developing a form of high-quality microstructured optical elements, improved imaging of malignancies and of treatment monitoring can be achieved. The results demonstrate a unique family of devices for in vitro and in vivo use that provide functional biomaterials with built-in optical signal and contrast enhancement, demonstrated here with simultaneous drug delivery and feedback about drug delivery with no adverse biological effects, all while slowly degrading to regenerate native tissue. PMID:23150544

  1. [Pathology of implants].

    PubMed

    Mittermayer, C; Eblenkamp, M; Richter, H A; Zwadlo-Klarwasser, G; Bhardwaj, R S; Klosterhalfen, B

    2002-01-01

    Progress in the surgery of implants and biomaterials can be accomplished by: 1. Painstakingly analysing and registering of defaulting implants after explantation within a "National Registry of Implant Pathology". 2. Development of a DNA-microarray named "Implantat/Chronic Wound" in order to discover the differential transcriptional activities of cells brought into contact with different foreign surfaces. 3. Predictive cell-engineering combined with custom-made implant surfaces with the aim of optimal patient care.

  2. P2RX7 polymorphisms Gln460Arg and His155Tyr are not associated with major depressive disorder or remission after SSRI or ECT.

    PubMed

    Viikki, Merja; Kampman, Olli; Anttila, Sami; Illi, Ari; Setälä-Soikkeli, Eija; Huuhka, Martti; Mononen, Nina; Lehtimäki, Terho; Leinonen, Esa

    2011-04-15

    Purinergic receptor P2X, ligand-gated ion channel, 7 (P2RX7) gene polymorphism, has been suggested to be associated with major depressive disorder (MDD). The association between P2RX7 gene polymorphism and remission after serotonin selective reuptake inhibitors (SSRI) or electroconvulsive therapy (ECT) has not previously been studied. The aims of the present study were to test for an association between P2RX7 polymorphisms Gln460Arg (rs2230912) and His155Tyr (rs208294) and MDD in two patient populations compared to controls. The first patient sample consisted of 119 subjects with treatment-resistant major depressive disorder, who were treated with ECT and the second of 99 depressive outpatients treated with SSRI. Genotype frequencies were also compared between remitters (Montgomery and Åsberg Depression Rating Scale (MADRS)<8) and non-remitters (defined as MADRS≥8) to SSRI or ECT treatment. There were no differences in allele or genotype frequencies of either rs2230912 or rs208294 between patient groups and controls. Neither rs2230912 nor rs208294 was associated with MDD or remission after SSRI or ECT. The results suggest that P2RX7 gene polymorphisms Gln460Arg (rs2230912) and His155Tyr (rs208294) are not associated with MDD or remission after SSRI or ECT.

  3. Ethical implications of implantable radiofrequency identification (RFID) tags in humans.

    PubMed

    Foster, Kenneth R; Jaeger, Jan

    2008-08-01

    This article reviews the use of implantable radiofrequency identification (RFID) tags in humans, focusing on the VeriChip (VeriChip Corporation, Delray Beach, FL) and the associated VeriMed patient identification system. In addition, various nonmedical applications for implanted RFID tags in humans have been proposed. The technology offers important health and nonhealth benefits, but raises ethical concerns, including privacy and the potential for coercive implantation of RFID tags in individuals. A national discussion is needed to identify the limits of acceptable use of implantable RFID tags in humans before their use becomes widespread and it becomes too late to prevent misuse of this useful but ethically problematic technology.

  4. Technology.

    ERIC Educational Resources Information Center

    Callison, Daniel

    2002-01-01

    Discussion of technology focuses on instructional technology. Topics include inquiry and technology; curriculum development; reflection and curriculum evaluation; criteria for technological innovations that will increase student motivation; standards; impact of new technologies on library media centers; software; and future trends. (LRW)

  5. Accelerating degradation rate of pure iron by zinc ion implantation.

    PubMed

    Huang, Tao; Zheng, Yufeng; Han, Yong

    2016-12-01

    Pure iron has been considered as a promising candidate for biodegradable implant applications. However, a faster degradation rate of pure iron is needed to meet the clinical requirement. In this work, metal vapor vacuum arc technology was adopted to implant zinc ions into the surface of pure iron. Results showed that the implantation depth of zinc ions was about 60 nm. The degradation rate of pure iron was found to be accelerated after zinc ion implantation. The cytotoxicity tests revealed that the implanted zinc ions brought a slight increase on cytotoxicity of the tested cells. In terms of hemocompatibility, the hemolysis of zinc ion implanted pure iron was lower than 2%. However, zinc ions might induce more adhered and activated platelets on the surface of pure iron. Overall, zinc ion implantation can be a feasible way to accelerate the degradation rate of pure iron for biodegradable applications. PMID:27482462

  6. Accelerating degradation rate of pure iron by zinc ion implantation

    PubMed Central

    Huang, Tao; Zheng, Yufeng; Han, Yong

    2016-01-01

    Pure iron has been considered as a promising candidate for biodegradable implant applications. However, a faster degradation rate of pure iron is needed to meet the clinical requirement. In this work, metal vapor vacuum arc technology was adopted to implant zinc ions into the surface of pure iron. Results showed that the implantation depth of zinc ions was about 60 nm. The degradation rate of pure iron was found to be accelerated after zinc ion implantation. The cytotoxicity tests revealed that the implanted zinc ions brought a slight increase on cytotoxicity of the tested cells. In terms of hemocompatibility, the hemolysis of zinc ion implanted pure iron was lower than 2%. However, zinc ions might induce more adhered and activated platelets on the surface of pure iron. Overall, zinc ion implantation can be a feasible way to accelerate the degradation rate of pure iron for biodegradable applications. PMID:27482462

  7. Implantation in IVF.

    PubMed

    Busso, Cristiano E; Melo, Marco A B; Fernandez, Manuel; Pellicer, Antonio; Simon, Carlos

    2006-01-01

    The recent advances in assisted reproduction have made it possible to study and interfere in almost every step of the human reproductive process except for implantation. The most complex and important step remains in great part unknown. Implantation in human has proven to be less efficient compared with other species. However, in in vitro fertilization (IVF) patients, it has been evaluated to be even poorer. This paper highlights the factors related to infertile patients and IVF treatments that can affect implantation and implantation's clinical aspects related to these treatments: implantation failure and early pregnancy loss.

  8. Trends in Cochlear Implants

    PubMed Central

    Zeng, Fan-Gang

    2004-01-01

    More than 60,000 people worldwide use cochlear implants as a means to restore functional hearing. Although individual performance variability is still high, an average implant user can talk on the phone in a quiet environment. Cochlear-implant research has also matured as a field, as evidenced by the exponential growth in both the patient population and scientific publication. The present report examines current issues related to audiologic, clinical, engineering, anatomic, and physiologic aspects of cochlear implants, focusing on their psychophysical, speech, music, and cognitive performance. This report also forecasts clinical and research trends related to presurgical evaluation, fitting protocols, signal processing, and postsurgical rehabilitation in cochlear implants. Finally, a future landscape in amplification is presented that requires a unique, yet complementary, contribution from hearing aids, middle ear implants, and cochlear implants to achieve a total solution to the entire spectrum of hearing loss treatment and management. PMID:15247993

  9. Breast implants. A review.

    PubMed

    Van Zele, D; Heymans, O

    2004-04-01

    Breast implants have been used for about four decades for both reconstructive and aesthetic purposes. In 1963, the quality of the artificial implants was revolutionized by the introduction of the silicone gel-filled implant. Since, this modern prosthesis has gone through an evolution of change and improvement with several types of devices with many variations and styles within each class. Actually, for the last three decades, approximately one million women have received silicone breast implants in the USA. But, in 1992, the American FDA banned silicone from the market, leaving saline implants as the only product generally available as an alternative until now. Other filler materials were introduced, but have never progressed beyond the experimental stage in the USA (in contrast with Europe). The evolution of the different implants through time, with their advantages and disadvantages will be discussed, but also the controversy on silicone implants in the USA and their suspected association with systemic diseases. PMID:15154572

  10. Informed Consent, Deaf Culture, and Cochlear Implants.

    PubMed

    Pass, Lauren; Graber, Abraham D

    2015-01-01

    While cochlear implantation is now considered routine in many parts of the world, the debate over how to ethically implement this technology continues. One's stance on implantation often hinges on one's understanding of deafness. On one end of the spectrum are those who see cochlear implants as a much needed cure for an otherwise intractable disability. On the other end of the spectrum are those who view the Deaf as members of a thriving culture and see the cochlear implant as an attempt to eliminate this culture. Rather than take a stance in this debate, we will argue that the informed consent process for cochlear implantation must include access to Deaf perspectives. Deaf individuals know best what it is like to be a member of the Deaf community; the reasonable person would put significant weight on the testimony of Deaf individuals when considering whether to undergo cochlear implantation. The reasonable person standard determines what information careproviders must present as part of the informed consent process; thus, informed consent for cochlear implantation requires access to the testimony of Deaf individuals. PMID:26399672

  11. Informed Consent, Deaf Culture, and Cochlear Implants.

    PubMed

    Pass, Lauren; Graber, Abraham D

    2015-01-01

    While cochlear implantation is now considered routine in many parts of the world, the debate over how to ethically implement this technology continues. One's stance on implantation often hinges on one's understanding of deafness. On one end of the spectrum are those who see cochlear implants as a much needed cure for an otherwise intractable disability. On the other end of the spectrum are those who view the Deaf as members of a thriving culture and see the cochlear implant as an attempt to eliminate this culture. Rather than take a stance in this debate, we will argue that the informed consent process for cochlear implantation must include access to Deaf perspectives. Deaf individuals know best what it is like to be a member of the Deaf community; the reasonable person would put significant weight on the testimony of Deaf individuals when considering whether to undergo cochlear implantation. The reasonable person standard determines what information careproviders must present as part of the informed consent process; thus, informed consent for cochlear implantation requires access to the testimony of Deaf individuals.

  12. Biomedical Imaging in Implantable Drug Delivery Systems

    PubMed Central

    Zhou, Haoyan; Hernandez, Christopher; Goss, Monika; Gawlik, Anna; Exner, Agata A.

    2015-01-01

    Implantable drug delivery systems (DDS) provide a platform for sustained release of therapeutic agents over a period of weeks to months and sometimes years. Such strategies are typically used clinically to increase patient compliance by replacing frequent administration of drugs such as contraceptives and hormones to maintain plasma concentration within the therapeutic window. Implantable or injectable systems have also been investigated as a means of local drug administration which favors high drug concentration at a site of interest, such as a tumor, while reducing systemic drug exposure to minimize unwanted side effects. Significant advances in the field of local DDS have led to increasingly sophisticated technology with new challenges including quantification of local and systemic pharmacokinetics and implant-body interactions. Because many of these sought-after parameters are highly dependent on the tissue properties at the implantation site, and rarely represented adequately with in vitro models, new nondestructive techniques that can be used to study implants in situ are highly desirable. Versatile imaging tools can meet this need and provide quantitative data on morphological and functional aspects of implantable systems. The focus of this review article is an overview of current biomedical imaging techniques, including magnetic resonance imaging (MRI), ultrasound imaging, optical imaging, X-ray and computed tomography (CT), and their application in evaluation of implantable DDS. PMID:25418857

  13. Using Clinical Decision Support and Dashboard Technology to Improve Heart Team Efficiency and Accuracy in a Transcatheter Aortic Valve Implantation (TAVI) Program.

    PubMed

    Clarke, Sarah; Wilson, Marisa L; Terhaar, Mary

    2016-01-01

    Heart Team meetings are becoming the model of care for patients undergoing transcatheter aortic valve implantations (TAVI) worldwide. While Heart Teams have potential to improve the quality of patient care, the volume of patient data processed during the meeting is large, variable, and comes from different sources. Thus, consolidation is difficult. Also, meetings impose substantial time constraints on the members and financial pressure on the institution. We describe a clinical decision support system (CDSS) designed to assist the experts in treatment selection decisions in the Heart Team. Development of the algorithms and visualization strategy required a multifaceted approach and end-user involvement. An innovative feature is its ability to utilize algorithms to consolidate data and provide clinically useful information to inform the treatment decision. The data are integrated using algorithms and rule-based alert systems to improve efficiency, accuracy, and usability. Future research should focus on determining if this CDSS improves patient selection and patient outcomes. PMID:27332170

  14. Nanotechnology Approaches for Better Dental Implants

    PubMed Central

    Tomsia, Antoni P.; Launey, Maximilien E.; Lee, Janice S.; Mankani, Mahesh H.; Wegst, Ulrike G.K.; Saiz, Eduardo

    2011-01-01

    The combined requirements imposed by the enormous scale and overall complexity of designing new implants or complete organ regeneration are well beyond the reach of present technology in many dimensions, including nanoscale, as we do not yet have the basic knowledge required to achieve these goals. The need for a synthetic implant to address multiple physical and biological factors imposes tremendous constraints on the choice of suitable materials. There is a strong belief that nanoscale materials will produce a new generation of implant materials with high efficiency, low cost, and high volume. The nanoscale in materials processing is truly a new frontier. Metallic dental implants have been successfully used for decades but they have serious shortcomings related to their osseointegration and the fact that their mechanical properties do not match those of bone. This paper reviews recent advances in the fabrication of novel coatings and nanopatterning of dental implants. It also provides a general summary of the state of the art in dental implant science and describes possible advantages of nanotechnology for further improvements. The ultimate goal is to produce materials and therapies that will bring state-of-the-art technology to the bedside and improve quality of life and current standards of care. PMID:21464998

  15. Nanotechnology approaches to improve dental implants.

    PubMed

    Tomisa, Antoni P; Launey, Maximilien E; Lee, Janice S; Mankani, Mahesh H; Wegst, Ulrike G K; Saiz, Eduardo

    2011-01-01

    The requirements imposed by the enormous scale and overall complexity of designing new implants or complete organ regeneration are well beyond the reach of present technology in many dimensions, including nanoscale, as researchers do not yet have the basic knowledge required to achieve these goals. The need for a synthetic implant to address multiple physical and biologic factors imposes tremendous constraints on the choice of suitable materials. There is a strong belief that nanoscale materials will produce a new generation of implant materials with high efficiency, low cost, and high volume. The nanoscale in materials processing is truly a new frontier. Metallic dental implants have been used successfully for decades, but they have serious shortcomings related to their osseointegration and the fact that their mechanical properties do not match those of bone. This paper reviews recent advances in the fabrication of novel coatings and nanopatterning of dental implants. It also provides a general summary of the state of the art in dental implant science and describes possible advantages of nanotechnology for future improvements. The ultimate goal is to produce materials and therapies that will bring state-of-the-art technology to the bedside and improve quality of life and current standards of care.

  16. Miniaturized neural interfaces and implants

    NASA Astrophysics Data System (ADS)

    Stieglitz, Thomas; Boretius, Tim; Ordonez, Juan; Hassler, Christina; Henle, Christian; Meier, Wolfgang; Plachta, Dennis T. T.; Schuettler, Martin

    2012-03-01

    Neural prostheses are technical systems that interface nerves to treat the symptoms of neurological diseases and to restore sensory of motor functions of the body. Success stories have been written with the cochlear implant to restore hearing, with spinal cord stimulators to treat chronic pain as well as urge incontinence, and with deep brain stimulators in patients suffering from Parkinson's disease. Highly complex neural implants for novel medical applications can be miniaturized either by means of precision mechanics technologies using known and established materials for electrodes, cables, and hermetic packages or by applying microsystems technologies. Examples for both approaches will be introduced and discussed. Electrode arrays for recording of electrocorticograms during presurgical epilepsy diagnosis have been manufactured using approved materials and a marking laser to achieve an integration density that is adequate in the context of brain machine interfaces, e.g. on the motor cortex. Microtechnologies have to be used for further miniaturization to develop polymer-based flexible and light weighted electrode arrays to interface the peripheral and central nervous system. Polyimide as substrate and insulation material will be discussed as well as several application examples for nerve interfaces like cuffs, filament like electrodes and large arrays for subdural implantation.

  17. Nanotechnology and dental implants.

    PubMed

    Lavenus, Sandrine; Louarn, Guy; Layrolle, Pierre

    2010-01-01

    The long-term clinical success of dental implants is related to their early osseointegration. This paper reviews the different steps of the interactions between biological fluids, cells, tissues, and surfaces of implants. Immediately following implantation, implants are in contact with proteins and platelets from blood. The differentiation of mesenchymal stem cells will then condition the peri-implant tissue healing. Direct bone-to-implant contact is desired for a biomechanical anchoring of implants to bone rather than fibrous tissue encapsulation. Surfaces properties such as chemistry and roughness play a determinant role in these biological interactions. Physicochemical features in the nanometer range may ultimately control the adsorption of proteins as well as the adhesion and differentiation of cells. Nanotechnologies are increasingly used for surface modifications of dental implants. Another approach to enhance osseointegration is the application of thin calcium phosphate (CaP) coatings. Bioactive CaP nanocrystals deposited on titanium implants are resorbable and stimulate bone apposition and healing. Future nanometer-controlled surfaces may ultimately direct the nature of peri-implant tissues and improve their clinical success rate.

  18. Nanotechnology and Dental Implants

    PubMed Central

    Lavenus, Sandrine; Louarn, Guy; Layrolle, Pierre

    2010-01-01

    The long-term clinical success of dental implants is related to their early osseointegration. This paper reviews the different steps of the interactions between biological fluids, cells, tissues, and surfaces of implants. Immediately following implantation, implants are in contact with proteins and platelets from blood. The differentiation of mesenchymal stem cells will then condition the peri-implant tissue healing. Direct bone-to-implant contact is desired for a biomechanical anchoring of implants to bone rather than fibrous tissue encapsulation. Surfaces properties such as chemistry and roughness play a determinant role in these biological interactions. Physicochemical features in the nanometer range may ultimately control the adsorption of proteins as well as the adhesion and differentiation of cells. Nanotechnologies are increasingly used for surface modifications of dental implants. Another approach to enhance osseointegration is the application of thin calcium phosphate (CaP) coatings. Bioactive CaP nanocrystals deposited on titanium implants are resorbable and stimulate bone apposition and healing. Future nanometer-controlled surfaces may ultimately direct the nature of peri-implant tissues and improve their clinical success rate. PMID:21253543

  19. A new method for Fourier analysis in ECG-gated cardiac blood pool emission computed tomography (ECT)

    SciTech Connect

    Ito, T.; Maeda, H.; Takeda, K.; Nakagawa, T.; Yamaguchi, N.; Konishi, T.; Ichikawa, T.

    1984-01-01

    An integrated technique for Fourier analysis in multigated blood pool ECT study has been developed. Following the administration of 15-20 mCi of Tc-99m RBC, ECG-gated cardiac blood pool data were acquired using an ECT system with dual opposed gamma cameras. Fundamental studies for data acquisition showed that acquisition time of 10 sec. for each projection, 14 divisions of one cardiac cycle and angular interval of 6/sup 0/ (60 projections over 360/sup 0/) were reasonable for clinical purpose. Total acquisition time was about 5 minutes under these conditions. Data were processed as follows: 1) Transaxial (TA) tomographic images in every phase of cardiac cycle were reconstructed by convolution algorithm; 2) TA images were rotated to construct sagittal (SAG) and short axial (S-A) oblique-angle tomography which are respectively parallel and perpendicular to the long axis of either of the ventricles; 3) Images covering the portion other than the purposed ventricle were eliminated from the series of SAG images in every phase of the cycle; 4) Images in the same phase were summed to construct a series of SAG and S-A planar images; and 5) Fourier analysis was made to construct phase and amplitude images. The advantages of this method are that the phase and amplitude images from arbitrary directions can be obtained, that the region of interest can be selected on a three dimensional basis, eliminating the overlapping activity of the other ventricle or neighbouring tissues, that the diseased areas can be easily and accurately localized even in small inferior wall myocardial infarction and that patient study can be finished within 5 minutes.

  20. Implants in adolescents

    PubMed Central

    Shah, Rohit A.; Mitra, Dipika K.; Rodrigues, Silvia V.; Pathare, Pragalbha N.; Podar, Rajesh S.; Vijayakar, Harshad N.

    2013-01-01

    Implants have gained tremendous popularity as a treatment modality for replacement of missing teeth in adults. There is extensive research present on the use of implants in adults, but there is a dearth of data available on the same in adolescents. The treatment planning and execution of implant placement in adolescents is still in its infancy. This review article is an attempt to bring together available literature. PMID:24174743

  1. Implantable cardioverter defibrillator - discharge

    MedlinePlus

    Baddour LM, Epstein AE, Erickson CC, et al. Update on cardiovascular implantable electronic device infections and their management: a scientific statement from the American Heart Association. Circulation . ...

  2. ReProTool Version 2.0: Re-Engineering Academic Curriculum Using Learning Outcomes, ECTS and Bologna Process Concepts

    ERIC Educational Resources Information Center

    Pouyioutas, Philippos; Gjermundrod, Harald; Dionysiou, Ioanna

    2012-01-01

    Purpose: The purpose of this paper is to present ReProTool Version 2.0, a software tool that is used for the European Credit Transfer System (ECTS) and the Bologna Process re-engineering of academic programmes. The tool is the result of an 18 months project (February 2012-July 2013) project, co-financed by the European Regional Development Fund…

  3. Combining Peer-Assessment with Negotiated Learning Activities on a Day-Release Undergraduate-Level Certificate Course (ECTS Level 3)

    ERIC Educational Resources Information Center

    McMahon, Tim

    2010-01-01

    Peer-assessment was used within a negotiated curriculum in a module on training and development at ECTS level 3. The students on the programme were exclusively day-release and all had a major responsibility for the management and delivery of work-based training programmes. Analysis of student evaluations, supplemented by those of university…

  4. Music perception with cochlear implants: a review.

    PubMed

    McDermott, Hugh J

    2004-01-01

    The acceptance of cochlear implantation as an effective and safe treatment for deafness has increased steadily over the past quarter century. The earliest devices were the first implanted prostheses found to be successful in compensating partially for lost sensory function by direct electrical stimulation of nerves. Initially, the main intention was to provide limited auditory sensations to people with profound or total sensorineural hearing impairment in both ears. Although the first cochlear implants aimed to provide patients with little more than awareness of environmental sounds and some cues to assist visual speech-reading, the technology has advanced rapidly. Currently, most people with modern cochlear implant systems can understand speech using the device alone, at least in favorable listening conditions. In recent years, an increasing research effort has been directed towards implant users' perception of nonspeech sounds, especially music. This paper reviews that research, discusses the published experimental results in terms of both psychophysical observations and device function, and concludes with some practical suggestions about how perception of music might be enhanced for implant recipients in the future. The most significant findings of past research are: (1) On average, implant users perceive rhythm about as well as listeners with normal hearing; (2) Even with technically sophisticated multiple-channel sound processors, recognition of melodies, especially without rhythmic or verbal cues, is poor, with performance at little better than chance levels for many implant users; (3) Perception of timbre, which is usually evaluated by experimental procedures that require subjects to identify musical instrument sounds, is generally unsatisfactory; (4) Implant users tend to rate the quality of musical sounds as less pleasant than listeners with normal hearing; (5) Auditory training programs that have been devised specifically to provide implant users with

  5. Synthesis of 5-hydroxyectoine from ectoine: crystal structure of the non-heme iron(II) and 2-oxoglutarate-dependent dioxygenase EctD.

    PubMed

    Reuter, Klaus; Pittelkow, Marco; Bursy, Jan; Heine, Andreas; Craan, Tobias; Bremer, Erhard

    2010-05-14

    As a response to high osmolality, many microorganisms synthesize various types of compatible solutes. These organic osmolytes aid in offsetting the detrimental effects of low water activity on cell physiology. One of these compatible solutes is ectoine. A sub-group of the ectoine producer's enzymatically convert this tetrahydropyrimidine into a hydroxylated derivative, 5-hydroxyectoine. This compound also functions as an effective osmostress protectant and compatible solute but it possesses properties that differ in several aspects from those of ectoine. The enzyme responsible for ectoine hydroxylation (EctD) is a member of the non-heme iron(II)-containing and 2-oxoglutarate-dependent dioxygenases (EC 1.14.11). These enzymes couple the decarboxylation of 2-oxoglutarate with the formation of a high-energy ferryl-oxo intermediate to catalyze the oxidation of the bound organic substrate. We report here the crystal structure of the ectoine hydroxylase EctD from the moderate halophile Virgibacillus salexigens in complex with Fe(3+) at a resolution of 1.85 A. Like other non-heme iron(II) and 2-oxoglutarate dependent dioxygenases, the core of the EctD structure consists of a double-stranded beta-helix forming the main portion of the active-site of the enzyme. The positioning of the iron ligand in the active-site of EctD is mediated by an evolutionarily conserved 2-His-1-carboxylate iron-binding motif. The side chains of the three residues forming this iron-binding site protrude into a deep cavity in the EctD structure that also harbours the 2-oxoglutarate co-substrate-binding site. Database searches revealed a widespread occurrence of EctD-type proteins in members of the Bacteria but only in a single representative of the Archaea, the marine crenarchaeon Nitrosopumilus maritimus. The EctD crystal structure reported here can serve as a template to guide further biochemical and structural studies of this biotechnologically interesting enzyme family.

  6. Synthesis of 5-hydroxyectoine from ectoine: crystal structure of the non-heme iron(II) and 2-oxoglutarate-dependent dioxygenase EctD.

    PubMed

    Reuter, Klaus; Pittelkow, Marco; Bursy, Jan; Heine, Andreas; Craan, Tobias; Bremer, Erhard

    2010-01-01

    As a response to high osmolality, many microorganisms synthesize various types of compatible solutes. These organic osmolytes aid in offsetting the detrimental effects of low water activity on cell physiology. One of these compatible solutes is ectoine. A sub-group of the ectoine producer's enzymatically convert this tetrahydropyrimidine into a hydroxylated derivative, 5-hydroxyectoine. This compound also functions as an effective osmostress protectant and compatible solute but it possesses properties that differ in several aspects from those of ectoine. The enzyme responsible for ectoine hydroxylation (EctD) is a member of the non-heme iron(II)-containing and 2-oxoglutarate-dependent dioxygenases (EC 1.14.11). These enzymes couple the decarboxylation of 2-oxoglutarate with the formation of a high-energy ferryl-oxo intermediate to catalyze the oxidation of the bound organic substrate. We report here the crystal structure of the ectoine hydroxylase EctD from the moderate halophile Virgibacillus salexigens in complex with Fe(3+) at a resolution of 1.85 A. Like other non-heme iron(II) and 2-oxoglutarate dependent dioxygenases, the core of the EctD structure consists of a double-stranded beta-helix forming the main portion of the active-site of the enzyme. The positioning of the iron ligand in the active-site of EctD is mediated by an evolutionarily conserved 2-His-1-carboxylate iron-binding motif. The side chains of the three residues forming this iron-binding site protrude into a deep cavity in the EctD structure that also harbours the 2-oxoglutarate co-substrate-binding site. Database searches revealed a widespread occurrence of EctD-type proteins in members of the Bacteria but only in a single representative of the Archaea, the marine crenarchaeon Nitrosopumilus maritimus. The EctD crystal structure reported here can serve as a template to guide further biochemical and structural studies of this biotechnologically interesting enzyme family. PMID:20498719

  7. Human pre-implantation embryo development

    PubMed Central

    Niakan, Kathy K.; Han, Jinnuo; Pedersen, Roger A.; Simon, Carlos; Pera, Renee A. Reijo

    2012-01-01

    Understanding human pre-implantation development has important implications for assisted reproductive technology (ART) and for human embryonic stem cell (hESC)-based therapies. Owing to limited resources, the cellular and molecular mechanisms governing this early stage of human development are poorly understood. Nonetheless, recent advances in non-invasive imaging techniques and molecular and genomic technologies have helped to increase our understanding of this fascinating stage of human development. Here, we summarize what is currently known about human pre-implantation embryo development and highlight how further studies of human pre-implantation embryos can be used to improve ART and to fully harness the potential of hESCs for therapeutic goals. PMID:22318624

  8. [The clinical practice guidelines of the Sociedad Española de Cardiología on the automatic implantable defibrillator].

    PubMed

    Pérez-Villacastín, J; Carmona Salinas, J R; Hernández Madrid, A; Marín Huerta, E; Merino Llorens, J L; Ormaetxe Merodio, J; Moya i Mitjans, A

    1999-12-01

    Since the first implantation in man in 1980 implantable cardioverter defibrillator technology has greatly improved and the number of devices implanted has increased considerably every year. Non thoracotomy lead systems and biphasic shocks are now the approach of choice, offering an almost 100% success rate. This document reviews the recommendations for qualification of personnel and for the centres implanting and carrying out follow-ups on defibrillators. The current indications for the implantation of implantable cardioverter defibrillator are also addressed.

  9. [Adjusting gingival tissues morphology after dental implantation with fibrin use].

    PubMed

    Maĭborodin, I V; Kolesnikov, I S; Sheplev, B V; Ragimova, T M; Kovyntsev, A N; Kovyntsev, D N; Shevela, A I

    2009-01-01

    In gingival tissues of 62 patients after dental implantation of traditional type and with the use of thrombocyte rich fibrin preparation (TRFP) microcirculation and leucocytal infiltration were studied. It was disclosed that in all terms after titanium screw dental implant setting lymphostasis and leucocytal infiltration were seen as signs of active inflammatory process in gingival tissues. 3 months later after implants setting with the use of TRFP the lymphatic vessels status was normalized, the degree of leucocytal infiltration was reduced; when implantation was made without use of fibrin technologies in gingival tissues more leucocytes were found and lymphatic bed components were remained dilated. Besides fibrin preparation use in the process of dental implantation promoted quicker and stronger implant fixation, but granulomatous inflammatory process could develop and amount of eosinophils in gingival tissues could also increased. PMID:19365340

  10. Tribological performance of surfaces enhanced by texturing and nitrogen implantation

    NASA Astrophysics Data System (ADS)

    Liu, Derong; Zhang, Qi; Qin, Zhenbo; Luo, Qin; Wu, Zhong; Liu, Lei

    2016-02-01

    In this paper, a novel texturing technology by means of electrodepositon is introduced. Textured surface covered with small bumps with the average size of 28 μm in diameter and 10 μm in height was fabricated. The trough around the bumps acts as the pocket to trap the debris. The nitrogen implantation was used to enhance the tribological properties of textured surfaces. The effects of implanted energy and dose on the structures of coating and tribological performances of textured surfaces were studied. The results show that the formation of Cr2N or CrN depends on the implanted dose. After nitrogen ion implantation, the friction coefficient of textured surface reduced and the wear resistance of textured surface was improved. The wear resistance enhances with increase of implanted dose, and has little to do with implanted energy.

  11. Ion implantations of oxide dispersion strengthened steels

    NASA Astrophysics Data System (ADS)

    Sojak, S.; Simeg Veternikova, J.; Slugen, V.; Petriska, M.; Stacho, M.

    2015-12-01

    This paper is focused on a study of radiation damage and thermal stability of high chromium oxide dispersion strengthened steel MA 956 (20% Cr), which belongs to the most perspective structural materials for the newest generation of nuclear reactors - Generation IV. The radiation damage was simulated by the implantation of hydrogen ions up to the depth of about 5 μm, which was performed at a linear accelerator owned by Slovak University of Technology. The ODS steel MA 956 was available for study in as-received state after different thermal treatments as well as in ions implanted state. Energy of the hydrogen ions chosen for the implantation was 800 keV and the implantation fluence of 6.24 × 1017 ions/cm2. The investigated specimens were measured by non-destructive technique Positron Annihilation Lifetime Spectroscopy in order to study the defect behavior after different thermal treatments in the as-received state and after the hydrogen ions implantation. Although, different resistance to defect production was observed in individual specimens of MA 956 during the irradiation, all implanted specimens contain larger defects than the ones in as-received state.

  12. Additively manufactured porous tantalum implants.

    PubMed

    Wauthle, Ruben; van der Stok, Johan; Amin Yavari, Saber; Van Humbeeck, Jan; Kruth, Jean-Pierre; Zadpoor, Amir Abbas; Weinans, Harrie; Mulier, Michiel; Schrooten, Jan

    2015-03-01

    The medical device industry's interest in open porous, metallic biomaterials has increased in response to additive manufacturing techniques enabling the production of complex shapes that cannot be produced with conventional techniques. Tantalum is an important metal for medical devices because of its good biocompatibility. In this study selective laser melting technology was used for the first time to manufacture highly porous pure tantalum implants with fully interconnected open pores. The architecture of the porous structure in combination with the material properties of tantalum result in mechanical properties close to those of human bone and allow for bone ingrowth. The bone regeneration performance of the porous tantalum was evaluated in vivo using an orthotopic load-bearing bone defect model in the rat femur. After 12 weeks, substantial bone ingrowth, good quality of the regenerated bone and a strong, functional implant-bone interface connection were observed. Compared to identical porous Ti-6Al-4V structures, laser-melted tantalum shows excellent osteoconductive properties, has a higher normalized fatigue strength and allows for more plastic deformation due to its high ductility. It is therefore concluded that this is a first step towards a new generation of open porous tantalum implants manufactured using selective laser melting.

  13. Additively manufactured porous tantalum implants.

    PubMed

    Wauthle, Ruben; van der Stok, Johan; Amin Yavari, Saber; Van Humbeeck, Jan; Kruth, Jean-Pierre; Zadpoor, Amir Abbas; Weinans, Harrie; Mulier, Michiel; Schrooten, Jan

    2015-03-01

    The medical device industry's interest in open porous, metallic biomaterials has increased in response to additive manufacturing techniques enabling the production of complex shapes that cannot be produced with conventional techniques. Tantalum is an important metal for medical devices because of its good biocompatibility. In this study selective laser melting technology was used for the first time to manufacture highly porous pure tantalum implants with fully interconnected open pores. The architecture of the porous structure in combination with the material properties of tantalum result in mechanical properties close to those of human bone and allow for bone ingrowth. The bone regeneration performance of the porous tantalum was evaluated in vivo using an orthotopic load-bearing bone defect model in the rat femur. After 12 weeks, substantial bone ingrowth, good quality of the regenerated bone and a strong, functional implant-bone interface connection were observed. Compared to identical porous Ti-6Al-4V structures, laser-melted tantalum shows excellent osteoconductive properties, has a higher normalized fatigue strength and allows for more plastic deformation due to its high ductility. It is therefore concluded that this is a first step towards a new generation of open porous tantalum implants manufactured using selective laser melting. PMID:25500631

  14. Batteryless implanted echosonometer

    NASA Technical Reports Server (NTRS)

    Kojima, G. K.

    1977-01-01

    Miniature ultrasonic echosonometer implanted within laboratory animals obtains energy from RF power oscillator that is electronically transduced via induction loop to power receiving loop located just under animal's skin. Method of powering device offers significant advantages over those in which battery is part of implanted package.

  15. Implantable, Ingestible Electronic Thermometer

    NASA Technical Reports Server (NTRS)

    Kleinberg, Leonard

    1987-01-01

    Small quartz-crystal-controlled oscillator swallowed or surgically implanted provides continuous monitoring of patient's internal temperature. Receiver placed near patient measures oscillator frequency, and temperature inferred from previously determined variation of frequency with temperature. Frequency of crystal-controlled oscillator varies with temperature. Circuit made very small and implanted or ingested to measure internal body temperature.

  16. Programming, Care, and Troubleshooting of Cochlear Implants for Children.

    ERIC Educational Resources Information Center

    Hedley-Williams, Andrea J.; Sladen, Douglas P.; Tharpe, Anne Marie

    2003-01-01

    This article provides an overview of current cochlear implant technology, programming strategies, troubleshooting, and care techniques. It considers: device components, initial stimulation, speech coding strategies, use and care, troubleshooting, and the classroom environment. (Contains references.) (DB)

  17. Graphene for Biomedical Implants

    NASA Astrophysics Data System (ADS)

    Moore, Thomas; Podila, Ramakrishna; Alexis, Frank; Rao, Apparao; Clemson Bioengineering Team; Clemson Physics Team

    2013-03-01

    In this study, we used graphene, a one-atom thick sheet of carbon atoms, to modify the surfaces of existing implant materials to enhance both bio- and hemo-compatibility. This novel effort meets all functional criteria for a biomedical implant coating as it is chemically inert, atomically smooth and highly durable, with the potential for greatly enhancing the effectiveness of such implants. Specifically, graphene coatings on nitinol, a widely used implant and stent material, showed that graphene coated nitinol (Gr-NiTi) supports excellent smooth muscle and endothelial cell growth leading to better cell proliferation. We further determined that the serum albumin adsorption on Gr-NiTi is greater than that of fibrinogen, an important and well understood criterion for promoting a lower thrombosis rate. These hemo-and biocompatible properties and associated charge transfer mechanisms, along with high strength, chemical inertness and durability give graphene an edge over most antithrombogenic coatings for biomedical implants and devices.

  18. Mechanical and Biological Interactions of Implants with the Brain and Their Impact on Implant Design

    PubMed Central

    Prodanov, Dimiter; Delbeke, Jean

    2016-01-01

    Neural prostheses have already a long history and yet the cochlear implant remains the only success story about a longterm sensory function restoration. On the other hand, neural implants for deep brain stimulation are gaining acceptance for variety of disorders including Parkinsons disease and obsessive-compulsive disorder. It is anticipated that the progress in the field has been hampered by a combination of technological and biological factors, such as the limited understanding of the longterm behavior of implants, unreliability of devices, biocompatibility of the implants among others. While the field's understanding of the cell biology of interactions at the biotic-abiotic interface has improved, relatively little attention has been paid on the mechanical factors (stress, strain), and hence on the geometry that can modulate it. This focused review summarizes the recent progress in the understanding of the mechanisms of mechanical interaction between the implants and the brain. The review gives an overview of the factors by which the implants interact acutely and chronically with the tissue: blood-brain barrier (BBB) breach, vascular damage, micromotions, diffusion etc. We propose some design constraints to be considered in future studies. Aspects of the chronic cell-implant interaction will be discussed in view of the chronic local inflammation and the ways of modulating it. PMID:26903786

  19. [Evaluation of asymmetric implants in breast augmentation surgery].

    PubMed

    Fitoussi, A D; Couturaud, B

    2005-10-01

    Since more than 30 years, the quality of breast implants has continued to evolve in order to improve the aesthetic results of prosthetic augmentation. Shapes and materials of these implants have also evolved to obtain stronger and more reliable prostheses almost similar to the natural breast. Therefore it can be considered that the use of asymmetric implants is the last step in implant technology before using made to measure implants. Asymmetric implants allow obtaining different contours in harmony to the different breast shapes capable to reproduce faithfully, in all dimensions, the anatomy of the female breast, including the differences between each side which maximise the naturalness of the result. Such implants have an axis directed towards the exterior and lower part of the chest wall, are wider than high with a thinner part on their inner edge and a concave rear side moulding the curves of the chest wall. In our own experience, we placed between 2002 and 2004, asymmetric implants in 100 patients. Such implants were easy to place and no secondary rotation was observed. The control of secondary displacements even in case of prosthesis change seems to be linked to their concave rear side, roughness and asymmetry. When analysing retrospectively the medical records, no distinctive features were observed when compared to symmetric classic implants in easiness in the surgical procedure or in complications except a slightly higher rate of seroma formation. However asymmetric implants are less appropriate in case of major breast ptosis, patients being unsatisfied by the "too natural" breast shape. Moreover a high risk of secondary rotation seems to be real in such cases. In summary, for all these reasons, asymmetric implants, are gradually considered to be a first-rank choice for implants in breast augmentation cosmetic surgery. PMID:16198044

  20. Technology.

    ERIC Educational Resources Information Center

    Giorgis, Cyndi; Johnson, Nancy J.

    2002-01-01

    Presents annotations of 30 works of children's literature that support the topic of technology and its influences on readers' daily lives. Notes some stories tell about a time when simple tools enabled individuals to accomplish tasks, and others feature visionaries who used technology to create buildings, bridges, roads, and inventions. Considers…

  1. Micro- and nano-fabricated implantable drug-delivery systems

    PubMed Central

    Meng, Ellis; Hoang, Tuan

    2013-01-01

    Implantable drug-delivery systems provide new means for achieving therapeutic drug concentrations over entire treatment durations in order to optimize drug action. This article focuses on new drug administration modalities achieved using implantable drug-delivery systems that are enabled by micro- and nano-fabrication technologies, and microfluidics. Recent advances in drug administration technologies are discussed and remaining challenges are highlighted. PMID:23323562

  2. Mobility implants: a review.

    PubMed

    Danz, W

    1990-01-01

    We present a brief review of mobility implants, their contribution, and the experiences derived after almost 40 years since the new concepts of full mobility implants were introduced. In early 1940, experiments with a new material for the making of plastic artificial eyes was also being considered for the making of orbital implants. Methyl-methacrylate (MMA) had proven inert and satisfactory for dental products. The Surgeon Generals office of the Armed Services encouraged further research and experimental work in the development of plastic eyes. The success of the new material sponsored the beginning of great expansion with new concepts for orbital implants. Through a period of more than a decade, the design and types of implants went through three stages. First, the buried implant was introduced, then the exposed integrated followed, and the buried integrated subsequently followed. The path of progress was not smooth. Theoretically correct designs and surgical procedures met unexpected practical difficulties for the ophthalmic surgeon, the patient, and the eye maker. Surgical and technical efforts were carefully reviewed to eliminate the problems encountered, only to have further unforeseen complications arise. Infections, extrusions, and migration of the implant were not uncommon. The exposed integrated implant was eventually abandoned. However, there were some extraordinary successes of mobility. A new era introduced fully buried mobility implants that were more successful. However, this procedure also produced some problems, causing infection (or allergy), extrusion, and migration. Tantalum mesh and gauze gave great promise with the inception of their use. Orbital tissue grew into the material in an astonishing way, making it possible to secure the extraocular muscles and tenons.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Nanotechnology for dental implants.

    PubMed

    Tomsia, Antoni P; Lee, Janice S; Wegst, Ulrike G K; Saiz, Eduardo

    2013-01-01

    With the advent of nanotechnology, an opportunity exists for the engineering of new dental implant materials. Metallic dental implants have been successfully used for decades, but they have shortcomings related to osseointegration and mechanical properties that do not match those of bone. Absent the development of an entirely new class of materials, faster osseointegration of currently available dental implants can be accomplished by various surface modifications. To date, there is no consensus regarding the preferred method(s) of implant surface modification, and further development will be required before the ideal implant surface can be created, let alone become available for clinical use. Current approaches can generally be categorized into three areas: ceramic coatings, surface functionalization, and patterning on the micro- to nanoscale. The distinctions among these are imprecise, as some or all of these approaches can be combined to improve in vivo implant performance. These surface improvements have resulted in durable implants with a high percentage of success and long-term function. Nanotechnology has provided another set of opportunities for the manipulation of implant surfaces in its capacity to mimic the surface topography formed by extracellular matrix components of natural tissue. The possibilities introduced by nanotechnology now permit the tailoring of implant chemistry and structure with an unprecedented degree of control. For the first time, tools are available that can be used to manipulate the physicochemical environment and monitor key cellular events at the molecular level. These new tools and capabilities will result in faster bone formation, reduced healing time, and rapid recovery to function.

  4. A novel ECT-EST combined method for gas-solids flow pattern and charge distribution visualization

    NASA Astrophysics Data System (ADS)

    Zhou, B.; Zhang, J. Y.

    2013-07-01

    A non-invasive measurement method of visualizing the flow pattern and charge distribution of gas-solids two-phase flow has been studied and verified using gravity-dropping and pneumatic conveyance rigs with pulverized coal as solids. It has been proven that the permittivity distribution acquired from an electrical capacitance tomography (ECT) system can be used to improve the accuracy in establishing charge sensitivity field of an electrostatic tomography (EST) system, and to reduce the uncertainty of charge distribution reconstruction. The experimental results show that, under the given experimental conditions for the gravity-dropping system, charge density increases with particles' concentration, whilst in the pneumatic conveyance system, charge density decreases in the area where the particles' concentration is higher, and the total charge intensity decreases with the increase of the concentration of pulverized coal in the pipe. The method proposed in this paper is potentially important in pneumatic processes for charge distribution measurement and safe operations. It is envisaged that with further development, this technique can provide information for investigation into the mechanism of inter-particle force on electrostatic attraction and repulsion.

  5. NASA's Van Allen Probes RBSP-ECT Data Products and Access to Them: An Insider's Outlook on the Inner and Outer Belts (and We Don't Mean the Nation's Beltway...)

    NASA Astrophysics Data System (ADS)

    Smith, S. S.; Friedel, R. H. W.; Henderson, M. G.; Larsen, B.; Reeves, G. D.; Spence, H. E.

    2014-12-01

    In this poster, we present a summary of access to the data products of the Radiation Belt Storm Probes - Energetic Particle Composition, and Thermal plasma (RBSP-ECT) suite of NASA's Van Allen Probes mission. The RBSP-ECT science investigation (http://rbsp-ect.sr.unh.edu) measures comprehensively the near-Earth charged particle environment in order to understand the processes that control the acceleration, global distribution, and variability of radiation belt electrons and ions. RBSP-ECT data products derive from the three instrument elements that comprise the suite, which collectively covers the broad energies that define the source and seed populations, the core radiation belts, and also their highest energy ultra-relativistic extensions. These RBSP-ECT instruments include, from lowest to highest energies: the Helium, Oxygen, Proton, and Electron (HOPE) sensor, the Magnetic Electron and Ion Spectrometer (MagEIS), and the Relativistic Electron and Proton Telescope (REPT). We provide a brief overview of their principles of operation, as well as a description of the Level 1-3 data products that the HOPE, MagEIS, and REPT instruments produce, both separately and together. We provide a summary of how to access these RBSP-ECT data products at our Science Operation Center and Science Data Center (http://www.rbsp-ect.lanl.gov/rbsp_ect.php ) as well as caveats for their use. Finally, in the spirit of efficiently and effectively promoting and encouraging new collaborations, we present a summary of past publications, current studies, and opportunities for your future participation in RBSP-ECT science analyses.

  6. NASA's RBSP-ECT Science Investigation of the Van Allen Probes Mission: Highlights of the Prime Mission Phase, Data Access Overview, and Opportunities to Collaborate in the Extended Mission Phase

    NASA Astrophysics Data System (ADS)

    Smith, S. S.; Friedel, R. H.; Larsen, B.; Reeves, G.; Spence, H. E.

    2015-12-01

    In this poster, we present a summary of access to the data products of the Radiation Belt Storm Probes - Energetic Particle Composition, and Thermal plasma (RBSP-ECT) suite of NASA's Van Allen Probes mission. The RBSP-ECT science investigation (http://rbsp-ect.sr.unh.edu) measures comprehensively the near-Earth charged particle environment in order to understand the processes that control the acceleration, global distribution, and variability of radiation belt electrons and ions. RBSP-ECT data products derive from the three instrument elements that comprise the suite, which collectively covers the broad energies that define the source and seed populations, the core radiation belts, and also their highest energy ultra-relativistic extensions. These RBSP-ECT instruments include, from lowest to highest energies: the Helium, Oxygen, Proton, and Electron (HOPE) sensor, the Magnetic Electron and Ion Spectrometer (MagEIS), and the Relativistic Electron and Proton Telescope (REPT). We provide a brief overview of their principles of operation, as well as a description of the Level 2-3 data products that the HOPE, MagEIS, and REPT instruments produce, both separately and together. We provide a summary of how to access these RBSP-ECT data products at our Science Operation Center and Science Data Center (http://www.rbsp-ect.lanl.gov/rbsp_ect.php ) as well as caveats for their use. Finally, in the spirit of efficiently and effectively promoting and encouraging new collaborations, we present a summary of past publications, current studies, and opportunities for your future participation in RBSP-ECT extended mission phase science.

  7. Spectroscopy of implants

    NASA Astrophysics Data System (ADS)

    Afanasyeva, Natalia I.

    1994-01-01

    The spectral criteria of selection of soft intraocular lens (IOL) implants of long service in an organism have been defined for ophthalmology. The analysis of Fourier Transform Infrared (FTIR) spectra provides the required and sufficient level of material polymerization for manufacturing non-toxic lenses for the eye. The spectral limits for determining the biocompatibility of samples can be related to the intensity ratio of two bands only in the FTIR spectra of siloxane. Siloxane-poly(urethane) block copolymers and other materials for implants have been studied. Passivated surfaces of implants have been obtained and registered by methods of Fourier Transform Spectroscopy.

  8. The evolution of embryo implantation.

    PubMed

    McGowen, Michael R; Erez, Offer; Romero, Roberto; Wildman, Derek E

    2014-01-01

    Embryo implantation varies widely in placental mammals. We review this variation in mammals with a special focus on two features: the depth of implantation and embryonic diapause. We discuss the two major types of implantation depth, superficial and interstitial, and map this character on a well-resolved molecular phylogenetic tree of placental mammals. We infer that relatively deep interstitial implantation has independently evolved at least eight times within placental mammals. Moreover, the superficial type of implantation represents the ancestral state for placental mammals. In addition, we review the genes involved in various phases of implantation, and suggest a future direction in investigating the molecular evolution of implantation-related genes. PMID:25023681

  9. Indications for an implantable cardioverter defibrillator (ICD).

    PubMed

    Aizawa, Yoshifusa; Chinushi, Masaomi; Washizuka, Takashi

    2004-05-01

    Since the first clinical use of implantable defibrillator in human, the technology and the function of implantable cardioverter-defibrillator (ICD) have been much improved and now, ICD can be implanted within the chest wall. ICD is the most reliable therapy to prevent sudden cardiac death (SCD) in patients with documented VT/VF and the efficacy is most clear in patients with depressed heart function. It is now extended as a tool of the primary prevention of SCD in high risk patients after myocardial infarction. However, such beneficial effect is not applicable to DCM though patients might have depressed heart function. ICD is not free from procedure- or device-related problems which need to be resolved. From unknown causes, VT/VF might recur in an incessant form and an emergency admission is needed. Therefore, even during ICD therapy, patients often require antiarrhythmic drugs or catheter ablation. PMID:15206546

  10. Dental implants from functionally graded materials.

    PubMed

    Mehrali, Mehdi; Shirazi, Farid Seyed; Mehrali, Mohammad; Metselaar, Hendrik Simon Cornelis; Kadri, Nahrizul Adib Bin; Osman, Noor Azuan Abu

    2013-10-01

    Functionally graded material (FGM) is a heterogeneous composite material including a number of constituents that exhibit a compositional gradient from one surface of the material to the other subsequently, resulting in a material with continuously varying properties in the thickness direction. FGMs are gaining attention for biomedical applications, especially for implants, owing to their reported superior composition. Dental implants can be functionally graded to create an optimized mechanical behavior and achieve the intended biocompatibility and osseointegration improvement. This review presents a comprehensive summary of biomaterials and manufacturing techniques researchers employ throughout the world. Generally, FGM and FGM porous biomaterials are more difficult to fabricate than uniform or homogenous biomaterials. Therefore, our discussion is intended to give the readers about successful and obstacles fabrication of FGM and porous FGM in dental implants that will bring state-of-the-art technology to the bedside and develop quality of life and present standards of care.

  11. Peri-Implant Diseases

    MedlinePlus

    ... and flossing and regular check-ups from a dental professional. Other risks factors for developing peri-implant disease include previous periodontal disease diagnosis, poor plaque control, smoking , and diabetes . It is essential to routinely ...

  12. Risks of Breast Implants

    MedlinePlus

    ... larger and longer than these conducted so far. Breastfeeding Some women who undergo breast augmentation can successfully ... breast implant silicone shell into breast milk during breastfeeding. Although there are currently no established methods for ...

  13. Ion implantation at elevated temperatures

    SciTech Connect

    Lam, N.Q.; Leaf, G.K.

    1985-11-01

    A kinetic model has been developed to investigate the synergistic effects of radiation-enhanced diffusion, radiation-induced segregation and preferential sputtering on the spatial redistribution of implanted solutes during implantation at elevated temperatures. Sample calculations were performed for Al and Si ions implanted into Ni. With the present model, the influence of various implantation parameters on the evolution of implant concentration profiles could be examined in detail.

  14. Implant treatment planning: endodontic considerations.

    PubMed

    Simonian, Krikor; Frydman, Alon; Verdugo, Fernando; Roges, Rafael; Kar, Kian

    2014-12-01

    Implants are a predictable and effective method for replacing missing teeth. Some clinicians have advocated extraction and replacement of compromised but treatable teeth on the assumption that implants will outperform endodontically and/or periodontally treated teeth. However, evidence shows that conventional therapy is as effective as implant treatment. With data on implants developing complications long term and a lack of predictable treatment for peri-implantitis, retaining and restoring the natural dentition should be the first choice when possible. PMID:25928961

  15. Cdc42 and the Guanine Nucleotide Exchange Factors Ect2 and Trio Mediate Fn14-Induced Migration and Invasion of Glioblastoma Cells

    PubMed Central

    Fortin, Shannon P.; Ennis, Matthew J.; Schumacher, Cassie A.; Zylstra-Diegel, Cassandra R.; Williams, Bart O.; Ross, Julianna T.D.; Winkles, Jeffrey A.; Loftus, Joseph C.; Symons, Marc H.; Tran, Nhan L.

    2012-01-01

    Malignant glioblastomas are characterized by their ability to infiltrate into normal brain. We previously reported that binding of the multifunctional cytokine TNF-like weak inducer of apoptosis (TWEAK) to its receptor fibroblast growth factor–inducible 14 (Fn14) induces glioblastoma cell invasion via Rac1 activation. Here, we show that Cdc42 plays an essential role in Fn14-mediated activation of Rac1. TWEAK-treated glioma cells display an increased activation of Cdc42, and depletion of Cdc42 using siRNA abolishes TWEAK-induced Rac1 activation and abrogates glioma cell migration and invasion. In contrast, Rac1 depletion does not affect Cdc42 activation by Fn14, showing that Cdc42 mediates TWEAK-stimulated Rac1 activation. Furthermore, we identified two guanine nucleotide exchange factors (GEF), Ect2 and Trio, involved in TWEAK-induced activation of Cdc42 and Rac1, respectively. Depletion of Ect2 abrogates both TWEAK-induced Cdc42 and Rac1 activation, as well as subsequent TWEAK-Fn14–directed glioma cell migration and invasion. In contrast, Trio depletion inhibits TWEAK-induced Rac1 activation but not TWEAK-induced Cdc42 activation. Finally, inappropriate expression of Fn14 or Ect2 in mouse astrocytes in vivo using an RCAS vector system for glial-specific gene transfer in G-tva transgenic mice induces astrocyte migration within the brain, corroborating the in vitro importance of the TWEAK-Fn14 signaling cascade in glioblastoma invasion. Our results suggest that the TWEAK-Fn14 signaling axis stimulates glioma cell migration and invasion through two GEF-GTPase signaling units, Ect2-Cdc42 and Trio-Rac1. Components of the Fn14-Rho GEF-Rho GTPase signaling pathway present innovative drug targets for glioma therapy. PMID:22571869

  16. Subcutaneous chronic implantable defibrillation systems in humans.

    PubMed

    Cappato, Riccardo; Smith, Warren M; Hood, Margaret A; Crozier, Ian G; Jordaens, Luc; Spitzer, Stefan G; Ardashev, Andrey V; Boersma, Lucas; Lupo, Pierpaolo; Grace, Andrew A; Bardy, Gust H

    2012-09-01

    The recent introduction of subcutaneous implantable cardioverter defibrillator (S-ICD) has raised attention about the potential of this technology for clinical use in daily clinical practice. We review the methods and results of the four studies conducted in humans for approval of this innovative technology for daily practice. Two studies using a temporary S-ICD system (acute human studies) were conducted to search for an appropriate lead configuration and energy requirements. For this purpose, 4 S-ICD configurations were tested in 78 patients at the time of transvenous (TV)-ICD implantation. The optimal configuration was tested in 49 more patients to comparatively assess the subcutaneous defibrillation threshold (S-DFT) versus the standard TV-ICD. Long-term implants were evaluated in 55 patients using an implanted system (chronic human study). The acute humans studies led to an optimal S-ICD configuration comprising a parasternal electrode and left anterolateral thoracic pulse generator. Both configurations successfully terminated 98% of induced ventricular fibrillation (VF), but significantly higher energy levels were required with S-ICD than with TV-ICD systems (36.6 ± 19.8 J vs. 11.1 ± 8.5 J). In the chronic study, all 137 VF episodes induced at time of implant were detected with a 98% conversion rate. Two pocket infections and four lead revisions were required during 10 ± 1 months of follow-up. During this period, survival was 98%, and 12 spontaneous ventricular tachyarrhythmias were detected and treated by the device. These data show that the S-ICD systems here consistently detected and converted VF induced at time of implant as well as sustained ventricular tachyarrhythmias occurring during follow-up (248). PMID:22426601

  17. Modular adaptive implant based on smart materials.

    PubMed

    Bîzdoacă, N; Tarniţă, Daniela; Tarniţă, D N

    2008-01-01

    Applications of biological methods and systems found in nature to the study and design of engineering systems and modern technology are defined as Bionics. The present paper describes a bionics application of shape memory alloy in construction of orthopedic implant. The main idea of this paper is related to design modular adaptive implants for fractured bones. In order to target the efficiency of medical treatment, the implant has to protect the fractured bone, for the healing period, undertaking much as is possible from the daily usual load of the healthy bones. After a particular stage of healing period is passed, using implant modularity, the load is gradually transferred to bone, assuring in this manner a gradually recover of bone function. The adaptability of this design is related to medical possibility of the physician to made the implant to correspond to patient specifically anatomy. Using a CT realistic numerical bone models, the mechanical simulation of different types of loading of the fractured bones treated with conventional method are presented. The results are commented and conclusions are formulated. PMID:19050799

  18. Biomaterials in cochlear implants

    PubMed Central

    Stöver, Timo; Lenarz, Thomas

    2011-01-01

    The cochlear implant (CI) represents, for almost 25 years now, the gold standard in the treatment of children born deaf and for postlingually deafened adults. These devices thus constitute the greatest success story in the field of ‘neurobionic’ prostheses. Their (now routine) fitting in adults, and especially in young children and even babies, places exacting demands on these implants, particularly with regard to the biocompatibility of a CI’s surface components. Furthermore, certain parts of the implant face considerable mechanical challenges, such as the need for the electrode array to be flexible and resistant to breakage, and for the implant casing to be able to withstand external forces. As these implants are in the immediate vicinity of the middle-ear mucosa and of the junction to the perilymph of the cochlea, the risk exists – at least in principle – that bacteria may spread along the electrode array into the cochlea. The wide-ranging requirements made of the CI in terms of biocompatibility and the electrode mechanism mean that there is still further scope – despite the fact that CIs are already technically highly sophisticated – for ongoing improvements to the properties of these implants and their constituent materials, thus enhancing the effectiveness of these devices. This paper will therefore discuss fundamental material aspects of CIs as well as the potential for their future development. PMID:22073103

  19. Simple Implant Augmentation Rhinoplasty.

    PubMed

    Nguyen, Anh H; Bartlett, Erica L; Kania, Katarzyna; Bae, Sang Mo

    2015-11-01

    Augmentation rhinoplasty among Asian patients is often performed to improve the height of the nasal dorsum. As the use of autogenous tissues poses certain limitations, alloplastic materials are a viable alternative with a long history of use in Asia. The superiority of one implant prosthesis over another for augmentation rhinoplasty is a matter of debate, with each material representing varying strengths and weaknesses, indications for use, and precautions to consider in nasal implant placement. An implant prosthesis should be used on a case-by-case basis. Augmentation rhinoplasty requires the consideration of specific anatomical preoperative factors, including the external nose, nasal length, nasofrontal angle, humps, and facial proportions. It is equally important to consider several operative guidelines to appropriately shape implants to minimize the occurrence of adverse effects and postoperative complications. The most common postoperative complications include infection, nasal height change, movement of implant prosthesis, and silicone implant protrusion. In addition, the surgeon should consider the current standards of Asian beauty aesthetics to better understand the patient's desired outcome. PMID:26648804

  20. Dexamethasone: intravitreal implant.

    PubMed

    2011-01-01

    Macular oedema is one of the complications of retinal vein occlusion. About half of the patients recover spontaneously within 3 to 6 months. There is currently no drug that improves outcome. An intravitreal implant delivering 0.7 mg of dexamethasone has been authorised for the treatment of macular oedema in this setting. Clinical assessment is based on two double-blind randomised trials including a total of 1267 patients, comparing treatment with intravitreal implants delivering about 0.7 mg or 0.35 mg of dexamethasone, versus a sham procedure. Despite a more rapid initial improvement with dexamethasone, the number of patients whose reading ability improved at 6 months did not significantly differ between the groups. A retrospective subgroup analysis raised the possibility that dexamethasone implants may be beneficial in patients with central retinal vein occlusion. The adverse effects of dexamethasone intravitreal implants are the same as those of intraocular steroid injections, including elevated intraocular pressure (25% of patients), cataracts (27%), conjunctival haemorrhage (20%), and ocular pain. In practice, dexamethasone intravitreal implants do not have a positive harm-benefit balance in most patients with macular oedema following retinal vein occlusion. More rapid recovery after central vein occlusion remains to be confirmed. Pending such studies, it is better to avoid using dexamethasone implants. Patients should instead receive ophthalmologic monitoring to detect and manage possible complications, and any risk factors should be treated.

  1. Annealing of PEEK, PET and PI implanted with Co ions at high fluencies

    NASA Astrophysics Data System (ADS)

    Mackova, A.; Malinsky, P.; Miksova, R.; Pupikova, H.; Khaibullin, R. I.; Valeev, V. F.; Svorcik, V.; Slepicka, P.

    2013-07-01

    The properties of implanted polymers strongly depend on the implantation ion fluence and on the properties of the implanted atoms. The stability of synthesized nano-structures during further technological steps like annealing is of importance for their possible applications. Polyimide (PI), polyetheretherketone (PEEK), and polyethyleneterephtalate (PET) were implanted with 40 keV Co+ ions at room temperature at fluences ranging from 0.2 × 1016 cm-2 to 1.0 × 1017 cm-2 and annealed at a temperature of 200 °C. The implanted depth profiles of as-implanted and annealed samples, determined by the RBS method, were compared with the results of SRIM 2012 simulations. The structural and compositional changes of the implanted and subsequently annealed polymers were characterized by RBS and UV-vis spectroscopy. The surface morphology of as-implanted and annealed samples was examined by the AFM method and their electrical properties by sheet resistance measurement.

  2. Technology.

    ERIC Educational Resources Information Center

    Online-Offline, 1998

    1998-01-01

    Focuses on technology, on advances in such areas as aeronautics, electronics, physics, the space sciences, as well as computers and the attendant progress in medicine, robotics, and artificial intelligence. Describes educational resources for elementary and middle school students, including Web sites, CD-ROMs and software, videotapes, books,…

  3. A touch probe method of operating an implantable RFID tag for orthopedic implant identification.

    PubMed

    Liu, Xiaoyu; Berger, J Lee; Ogirala, Ajay; Mickle, Marlin H

    2013-06-01

    The major problem in operating an implantable radio-frequency identification (RFID) tag embedded on an orthopedic implant is low efficiency because of metallic interference. To improve the efficiency, this paper proposes a method of operating an implantable passive RFID tag using a touch probe at 13.56 MHz. This technology relies on the electric field interaction between two pairs of electrodes, one being a part of the touch probe placed on the surface of tissue and the other being a part of the tag installed under the tissue. Compared with using a conventional RFID antenna such as a loop antenna, this method has a better performance in the near field operation range to reduce interference with the orthopedic implant. Properly matching the touch probe and the tag to the tissue and the implant reduces signal attenuation and increases the overall system efficiency. The experiments have shown that this method has a great performance in the near field transcutaneous operation and can be used for orthopedic implant identification.

  4. WE-A-17A-09: Exploiting Electromagnetic Technologies for Real-Time Seed Drop Position Validation in Permanent Implant Brachytherapy

    SciTech Connect

    Racine, E; Hautvast, G; Binnekamp, D; Beaulieu, L

    2014-06-15

    Purpose: To report on preliminary results validating the performance of a specially designed LDR brachytherapy needle prototype possessing both electromagnetic (EM) tracking and seed drop detection abilities. Methods: An EM hollow needle prototype has been designed and constructed in collaboration with research partner Philips Healthcare. The needle possesses conventional 3D tracking capabilities, along with a novel seed drop detection mechanism exploiting local changes of electromagnetic properties generated by the passage of seeds in the needle's embedded sensor coils. These two capabilities are exploited by proprietary engineering and signal processing techniques to generate seed drop position estimates in real-time treatment delivery. The electromagnetic tracking system (EMTS) used for the experiment is the NDI Aurora Planar Field Generator. The experiment consisted of dropping a total of 35 seeds in a prismatic agarose phantom, and comparing the 3D seed drop positions of the EMTS to those obtained by an image analysis of subsequent micro-CT scans. Drop position error computations and statistical analysis were performed after a 3D registration of the two seed distributions. Results: Of the 35 seeds dropped in the phantom, 32 were properly detected by the needle prototype. Absolute drop position errors among the detected seeds ranged from 0.5 to 4.8 mm with mean and standard deviation values of 1.6 and 0.9 mm, respectively. Error measurements also include undesirable and uncontrollable effects such as seed motion upon deposition. The true accuracy performance of the needle prototype is therefore underestimated. Conclusion: This preliminary study demonstrates the potential benefits of EM technologies in detecting the passage of seeds in a hollow needle as a means of generating drop position estimates in real-time treatment delivery. Such tools could therefore represent a potentially interesting addition to existing brachytherapy protocols for rapid dosimetry

  5. The Biolink Implantable Telemetry System

    NASA Technical Reports Server (NTRS)

    Betancourt-Zamora, Rafael J.

    1999-01-01

    process. Measured phase noise for a 1.5mW, 200MHz ring oscillator VCO is -80dBc/Hz at 100KHZ offset, showing good agreement with the theory. We also propose a novel superregenerative receiver architecture for implementing the command receiver. The superregenerative receiver's simplicity, low cost, and low power consumption has made it the receiver of choice for short-distance data communications, remote control and home automation. We present the design of a superregenerative AM receiver implemented in a 0.5um CMOS technology that operates at 433.92MHz and dissipates only 300uW. Further work entails detailed transistor-level design of the FLL and superregenerative receiver and a monolithic implementation of an implantable transceiver in 0.5um CMOS technology.

  6. Nanoscale nonlinear effects in Erbium-implanted Yttrium Orthosilicate

    NASA Astrophysics Data System (ADS)

    Kukharchyk, Nadezhda; Shvarkov, Stepan; Probst, Sebastian; Xia, Kangwei; Becker, Hans-Werner; Pal, Shovon; Markmann, Sergej; Kolesov, Roman; Siyushev, Petr; Wrachtrup, Jörg; Ludwig, Arne; Ustinov, Alexey V.; Wieck, Andreas D.; Bushev, Pavel

    2016-09-01

    Doping of substrates at desired locations is a key technology for spin-based quantum memory devices. Focused ion beam implantation is well-suited for this task due to its high spacial resolution. In this work, we investigate ion-beam implanted erbium ensembles in Yttrium Orthosilicate crystals by means of confocal photoluminescence spectroscopy. The sample temperature and the post-implantation annealing step strongly reverberate in the properties of the implanted ions. We find that hot implantation leads to a higher activation rate of the ions. At high enough fluences, the relation between the fluence and final concentration of ions becomes non-linear. Two models are developed explaining the observed behaviour.

  7. Implant interactions with orthodontics.

    PubMed

    Celenza, Frank

    2012-09-01

    Many situations arise in which orthodontic therapy in conjunction with implant modalities is beneficial, relevant or necessary. These situations might entail orthodontic treatment preparatory to the placement of an implant, such as in the site preparation for implant placement. Traditionally, this has been somewhat well understood, but there are certain guidelines that must be adhered to as well as diagnostic steps that must be followed. Provision of adequate space for implant placement is of paramount importance, but there is also the consideration of tissue manipulation and remodeling which orthodontic therapy can achieve very predictably and orthodontists should be well versed in harnessing and employing this modality of site preparation. In this way, hopeless teeth that are slated for extraction can still be utilized by orthodontic extraction to augment tissues, both hard and soft, thereby facilitating site development. On the corollary, and representing a significant shift in treatment sequencing, there are many situations in which orthodontic mechanotherapy can be simplified, expedited, and facilitated by the placement of an implant and utilization as an integral part of the mechanotherapy. Implants have proven to provide excellent anchorage, and have resulted in a new class of anchorage known as "absolute anchorage". Implants can be harnessed as anchors both in a direct and indirect sense, depending upon the dictates of the case. Further, this has led to the development of orthodontic miniscrew systems and techniques, which can have added features such as flexibility in location and placement, as well as ease of use and removal. As orthodontic appliances evolve, the advent of aligner therapy has become mainstream and well accepted, and many of the aforementioned combined treatment modalities can and should be incorporated into this relatively new treatment modality as well. PMID:23040348

  8. Integration of an Axcelis Optima HD Single Wafer High Current Implanter for p- and n-S/D Implants in an Existing Batch Implanter Production Line

    SciTech Connect

    Schmeide, Matthias; Kontratenko, Serguei; Krimbacher, Bernhard; Mueller, Ralf Peter

    2008-11-03

    This paper is focused on the integration and qualification of an Axcelis Optima HD single wafer high current spot beam implanter in an existing 200 mm production line with different types of Axcelis batch implanters for high current applications. Both the design of the beamline and the beam shape are comparable between single wafer and batch high current spot beam implanters. In contrast to the single wafer high current ribbon beam implanter, energy contamination is not a concern for the considered spot beam tool because the drift mode can be used down to energies in the 2 keV region. The most important difference between single wafer and batch high current implanters is the significantly higher dose rate and, therefore, the higher damage rate for the single wafer tool due to the different scanning architecture. The results of the integration of high dose implantations, mainly for p- and n-S/D formation, for DRAM 110 nm without pre-amorphization implantation (PAI), CMOS Logic from around 250 nm down to 90 nm without and with PAI, are presented and discussed. Dopant concentration profile analysis using SIMS was performed for different technologies and implantation conditions. The impurity activation was measured using sheet resistance and in some cases spreading resistance technique was applied. The amorphous layer thickness was measured using TEM. Finally, device data are presented in combination with dose, energy and beam current variations. The results have shown that the integration of implantation processes into crystalline structure without PAI is more complex and time consuming than implantations into amorphous layer where the damage difference due to the different dose rates is negligible.

  9. Scuba diving with cochlear implants.

    PubMed

    Kompis, Martin; Vibert, Dominique; Senn, Pascal; Vischer, Mattheus W; Häusler, Rudolf

    2003-05-01

    We report on a patient with bilateral cochlear implants (a Med-El Combi40 and a Med-El Combi40+), as well as considerable experience in scuba diving with both of his implants. After having been exposed to 68 and 89 dives, respectively, in depths of up to 43 m, both cochlear implants are in working order and the patient continues to receive excellent speech recognition scores with both cochlear implant systems. The presented data show that scuba diving after cochlear implantation is possible over a considerable number of dives without any major negative impact on the implants.

  10. Mometasone implant for chronic rhinosinusitis.

    PubMed

    Wei, Calvin C; Kennedy, David W

    2012-01-01

    The Propel mometasone-eluting stent (Intersect ENT, Palo Alto, CA) is the first Food and Drug Administration-approved device for delivering steroid medication into the ethmoid cavity following surgery. The implant is composed of a biodegradable polymer in a lattice pattern that expands in a spring-like fashion to conform to the walls of a dissected ethmoid cavity and contains a total of 370 μg of mometasone furoate designed for gradual release over 30 days. The purpose of this article is to review the mode of action and the evidence supporting the efficacy of this novel technology. Three recently published clinical trials have demonstrated that the mometasone-eluting stent produced statistically significant reductions in inflammation, polyp formation, and postoperative adhesions. In addition, the implant has been found to significantly reduce the need for postoperative administration of oral steroids and to decrease the frequency of postoperative lysis of adhesions. Minimal adverse effects were reported in these trials and included infection, crusting, and granulation tissue formation. Although the placement of steroid-impregnated packing, stents, sponges, and gels has previously been used in the postoperative sinus cavities, the Propel mometasone-eluting stent introduces a new mechanism for localized and controlled delivery of topical therapy directly to the nasal mucosa for chronic rhinosinusitis.

  11. Modulation Techniques for Biomedical Implanted Devices and Their Challenges

    PubMed Central

    Hannan, Mahammad A.; Abbas, Saad M.; Samad, Salina A.; Hussain, Aini

    2012-01-01

    Implanted medical devices are very important electronic devices because of their usefulness in monitoring and diagnosis, safety and comfort for patients. Since 1950s, remarkable efforts have been undertaken for the development of bio-medical implanted and wireless telemetry bio-devices. Issues such as design of suitable modulation methods, use of power and monitoring devices, transfer energy from external to internal parts with high efficiency and high data rates and low power consumption all play an important role in the development of implantable devices. This paper provides a comprehensive survey on various modulation and demodulation techniques such as amplitude shift keying (ASK), frequency shift keying (FSK) and phase shift keying (PSK) of the existing wireless implanted devices. The details of specifications, including carrier frequency, CMOS size, data rate, power consumption and supply, chip area and application of the various modulation schemes of the implanted devices are investigated and summarized in the tables along with the corresponding key references. Current challenges and problems of the typical modulation applications of these technologies are illustrated with a brief suggestions and discussion for the progress of implanted device research in the future. It is observed that the prime requisites for the good quality of the implanted devices and their reliability are the energy transformation, data rate, CMOS size, power consumption and operation frequency. This review will hopefully lead to increasing efforts towards the development of low powered, high efficient, high data rate and reliable implanted devices. PMID:22368470

  12. Immunological aspects of implantation and implantation failure.

    PubMed

    Johnson, P M; Christmas, S E; Vince, G S

    1999-12-01

    The human endometrium contains a significant proportion of leukocytes (8-35% of all cells), the absolute numbers and proportions varying during both the menstrual cycle and early in pregnancy. T cells, macrophages and a population of phenotypically unusual large granular lymphocytes (LGL) are commonly present, although B cells are absent. Relative T cell numbers decrease significantly in first trimester decidua, and hence are unlikely to play an important role in maintenance of human pregnancy, but T cells could be important in implantation where their relative numbers are greater. In addition to producing cytokines, local tissue macrophages may provide an immediate antigen non-specific host defence to infection. Most attention has, nevertheless, focused on a role for LGL in implantation and maintenance of pregnancy since, at the time of implantation, LGL comprise 70-80% of the total endometrial leukocyte population. Although endometrial LGL have been shown to express natural killer (NK) cell-type cytotoxicity against classical NK cell targets, such cytotoxicity against trophoblast is induced only after activation by interleukin (IL)-2. Selective expression of the unusual class I human leukocyte antigen (HLA) molecule, HLA-G, by extravillous cytotrophoblast may assist in protecting invasive cytotrophoblast from potential maternal NK cell attack, probably via interactions with killer inhibitory receptor molecules on LGL. Many cytokines have been demonstrated to be expressed at the maternal-fetal interface although, currently, in mice only two (IL-11 and leukaemia inhibitory factor) appear to be absolutely essential for successful pregnancy outcome. Immune effector cells and cytokines may also play a role in human pregnancy pathologies, such as recurrent early pregnancy loss.

  13. Ethical implications of implantable radiofrequency identification (RFID) tags in humans.

    PubMed

    Foster, Kenneth R; Jaeger, Jan

    2008-08-01

    This article reviews the use of implantable radiofrequency identification (RFID) tags in humans, focusing on the VeriChip (VeriChip Corporation, Delray Beach, FL) and the associated VeriMed patient identification system. In addition, various nonmedical applications for implanted RFID tags in humans have been proposed. The technology offers important health and nonhealth benefits, but raises ethical concerns, including privacy and the potential for coercive implantation of RFID tags in individuals. A national discussion is needed to identify the limits of acceptable use of implantable RFID tags in humans before their use becomes widespread and it becomes too late to prevent misuse of this useful but ethically problematic technology. PMID:18802863

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

    PubMed Central

    Mangano, Francesco; Shibli, Jamil Awad; Anil, Sukumaran

    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. PMID:25580124

  15. Dental Implant Complications.

    PubMed

    Liaw, Kevin; Delfini, Ronald H; Abrahams, James J

    2015-10-01

    Dental implants have increased in the last few decades thus increasing the number of complications. Since many of these complications are easily diagnosed on postsurgical images, it is important for radiologists to be familiar with them and to be able to recognize and diagnose them. Radiologists should also have a basic understanding of their treatment. In a pictorial fashion, this article will present the basic complications of dental implants which we have divided into three general categories: biomechanical overload, infection or inflammation, and other causes. Examples of implant fracture, loosening, infection, inflammation from subgingival cement, failure of bone and soft tissue preservation, injury to surround structures, and other complications will be discussed as well as their common imaging appearances and treatment. Lastly, we will review pertinent dental anatomy and important structures that are vital for radiologists to evaluate in postoperative oral cavity imaging.

  16. REVIEW ARTICLE: Medical implants based on microsystems

    NASA Astrophysics Data System (ADS)

    Mokwa, W.

    2007-05-01

    The fast development of CMOS technologies to smaller dimensions led to very high integration densities with complex circuitry on very small chip areas. In 2006 Intel fabricated the first products in a 65 nm technology. The cointegration of microsensors or actuators together with the very low power consumption of the CMOS circuitry is very well suited for use in implanted systems. Applications like intracranial or intraocular pressure measurements have become possible. This review presents an overview over actual applications and developments of sensor/actuator-based microsystems for medical implants. It concentrates on the technical part of these investigations. It will mainly review work on systems measuring pressure in blood vessels and on systems for ophthalmic applications.

  17. GaAs Hall devices produced by local ion implantation

    NASA Astrophysics Data System (ADS)

    Pettenpaul, E.; Huber, J.; Weidlich, H.; Flossmann, W.; von Borcke, U.

    1981-08-01

    GaAs Hall devices were produced by complete planar technology using two selective silicon ion implantation steps. The fundamental characteristics of these devices with respect to reproducible implantation dose and geometry of cross-shaped elements are obtained both by experiment and calculation. The prominent properties of the GaAs Hall elements presented are high sensitivity and linearity, small temperature dependence of sensitivity and resistance, and low residual voltage.

  18. Hydroxylapatite Otologic Implants

    SciTech Connect

    McMillan, A.D.; Lauf, R.J.; Beale, B.; Johnson, R.

    2000-01-01

    A Cooperative Research and Development Agreement (CRADA) between Lockheed Martin Energy Research Corporation (LMER) and Smith and Nephew Richards Inc. of Bartlett, TN, was initiated in March 1997. The original completion date for the Agreement was March 25, 1998. The purpose of this work is to develop and commercialize net shape forming methods for directly creating dense hydroxylapatite (HA) ceramic otologic implants. The project includes three tasks: (1) modification of existing gelcasting formulations to accommodate HA slurries; (2) demonstration of gelcasting to fabricate green HA ceramic components of a size and shape appropriate to otologic implants: and (3) sintering and evaluation of the HA components.

  19. Multichannel extracochlear implant.

    PubMed

    Pulec, J L; Smith, J C; Lewis, M L; Hortmann, G

    1989-03-01

    The transcutaneous eight-channel extracochlear implant has undergone continuous revision to simplify the surgical technique, to minimize patient morbidity, and to improve performance. The extracochlear electrode array has been miniaturized so that it can be inserted through the facial recess without disturbing the external auditory canal, tympanic membrane, or malleus. The use of the remote antenna placed around the external auditory canal has greatly increased battery life and patient comfort. With its simplified incisions, the surgical procedure can be performed as out-patient surgery. Preoperative cochlear nerve testing and use of evoked response cochlear nerve testing allow preadjustment of the speech processor. Current features and performance of the implant are discussed.

  20. Ion implantation in silicate glasses

    SciTech Connect

    Arnold, G.W.

    1993-12-01

    This review examines the effects of ion implantation on the physical properties of silicate glasses, the compositional modifications that can be brought about, and the use of metal implants to form colloidal nanosize particles for increasing the nonlinear refractive index.

  1. [Cochlear implant in children: rational, indications and cost/efficacy].

    PubMed

    Martini, A; Bovo, R; Trevisi, P; Forli, F; Berrettini, S

    2013-06-01

    this advantage persists in the subsequent years. With regard to cochlear implantation in children older than 12 months the studies show better hearing and linguistic results in children implanted at earlier ages. A sensitive period under 24-36 months has been identified over which cochlear implantation is reported to be less effective in terms of improvement in speech and hearing results. With regard to clinical effectiveness of bilateral cochlear implantation, greater benefits from bilateral implants compared to monolateral ones when assessing hearing in quiet and in noise and in sound localization abilities are reported to be present in both case of simultaneous or sequential bilateral implantation. However, with regard to the delay between the surgeries in sequential bilateral implantation, although benefit is reported to be present even after very long delays, on average long delays between surgeries seems to negatively affect the outcome with the second implant. With regard to benefits after cochlear implantation in children with multiple disabilities, benefits in terms of speech perception and communication as well as in quality of the daily life are reported even if benefits are slower and lower in comparison to those generally attained by implanted children without additional disabilities. Regarding the costs/efficacy ratio, the CI is expensive, in particular because of the cost of the high technological device, long life support, but even if healthcare costs are high, the savings in terms of indirect costs and quality of life are important. The CI, in fact, has a positive impact in terms of quality of life. PMID:23685383

  2. The ruptured PIP breast implant.

    PubMed

    Helyar, V; Burke, C; McWilliams, S

    2013-08-01

    Public concern erupted about the safety of Poly Implant Prothèse (PIP) breast implants when it was revealed in 2011 that they contained an inferior, unlicensed industrial-grade silicone associated with a high rate of rupture. There followed national guidance for UK clinicians, which led to a considerable increase in referrals of asymptomatic women for breast implant assessment. In this review we discuss possible approaches to screening the PIP cohort and the salient characteristics of a ruptured implant. PMID:23622796

  3. MEAT SCIENCE AND MUSCLE BIOLOGY SYMPOSIUM--anabolic implants and meat quality.

    PubMed

    Duckett, S K; Pratt, S L

    2014-01-01

    Anabolic implants are routinely used in the finishing phase of beef production to improve animal performance and feed efficiency. Implanting during the feedlot phase on average increases ADG 18%, feed intake 6%, feed efficiency 8%, carcass weight 5%, and ribeye area 4% compared with nonimplanted controls. Implants reduce the cost of beef production, which is important given current high feed costs and beef prices. In a 1996 review of 37 implant trials, the use of a combination (i.e., estrogenic and trenbolone acetate) implant increased returns by US$77/head compared with nonimplanted steers. If calculated using today's prices, a combination implant would increase returns by $163/head. However, concerns about potential negative effects of implants on marbling scores, quality grades, and tenderness exist. Changes in Warner-Bratzler shear force values of steaks from implanted steers are small (<0.5 kg) and appear related to an increase in initial tenderness, possibly due to hypertrophy of muscle fiber, instead of alterations in postmortem proteolysis. The increase in ribeye size observed with implanting may also reduce marbling scores through a dilution effect. The impact of anabolic implants on gene expression has shown that implanting downregulates expression of certain lipogenic genes (e.g., stearoyl-CoA desaturase, fatty acid synthetase, fatty acid elongase-6) in steers with low quality grades (Select-) but not in implanted steers with high quality grades (Choice-). Examination of the adipocyte's transcriptome has shown that 36 genes were differentially expressed due to implant treatment. More research is needed to further determine how anabolic implants alter lipogenic gene expression to address changes in marbling deposition with implant usage. Given our current high feed costs and cattle prices, anabolic implants are one of the most cost-effective technologies that can be used in beef production systems.

  4. Elementary Implantable Force Sensor

    PubMed Central

    Wachs, Rebecca A.; Ellstein, David; Drazan, John; Healey, Colleen P.; Uhl, Richard L.; Connor, Kenneth A.

    2014-01-01

    Implementing implantable sensors which are robust enough to maintain long term functionality inside the body remains a significant challenge. The ideal implantable sensing system is one which is simple and robust; free from batteries, telemetry, and complex electronics. We have developed an elementary implantable sensor for orthopaedic smart implants. The sensor requires no telemetry and no batteries to communicate wirelessly. It has no on-board signal conditioning electronics. The sensor itself has no electrical connections and thus does not require a hermetic package. The sensor is an elementary L-C resonator which can function as a simple force transducer by using a solid dielectric material of known stiffness between two parallel Archimedean coils. The operating characteristics of the sensors are predicted using a simplified, lumped circuit model. We have demonstrated sensor functionality both in air and in saline. Our preliminary data indicate that the sensor can be reasonably well modeled as a lumped circuit to predict its response to loading. PMID:24883335

  5. Remote actuated valve implant

    DOEpatents

    McKnight, Timothy E.; Johnson, Anthony; Moise, Kenneth J.; Ericson, Milton Nance; Baba, Justin S.; Wilgen, John B.; Evans, Boyd Mccutchen

    2016-05-10

    Valve implant systems positionable within a flow passage, the systems having an inlet, an outlet, and a remotely activatable valve between the inlet and outlet, with the valves being operable to provide intermittent occlusion of the flow path. A remote field is applied to provide thermal or magnetic activation of the valves.

  6. Ion implantation in polymers

    NASA Astrophysics Data System (ADS)

    Wintersgill, M. C.

    1984-02-01

    An introductory overview will be given of the effects of ion implantation on polymers, and certain areas will be examined in more detail. Radiation effects in general and ion implantation in particular, in the field of polymers, present a number of contrasts with those in ionic crystals, the most obvious difference being that the chemical effects of both the implanted species and the energy transfer to the host may profoundly change the nature of the target material. Common effects include crosslinking and scission of polymer chains, gas evolution, double bond formation and the formation of additional free radicals. Research has spanned the chemical processes involved, including polymerization reactions achievable only with the use of radiation, to applied research dealing both with the effects of radiation on polymers already in commercial use and the tailoring of new materials to specific applications. Polymers are commonly divided into two groups, in describing their behavior under irradiation. Group I includes materials which form crosslinks between molecules, whereas Group II materials tend to degrade. In basic research, interest has centered on Group I materials and of these polyethylene has been studied most intensively. Applied materials research has investigated a variety of polymers, particularly those used in cable insulation, and those utilized in ion beam lithography of etch masks. Currently there is also great interest in enhancing the conducting properties of polymers, and these uses would tend to involve the doping capabilities of ion implantation, rather than the energy deposition.

  7. Peritoneal trophoblastic implant.

    PubMed

    Rachagan, S P; Kutty, K; Govindan, K S

    1997-09-01

    A case of persistent trophoblastic tissue on the pelvic peritoneum is presented. While most cases are secondary to conservative surgery for tubal ectopic pregnancy, primary implantation can also occur as highlighted by this case. A brief pathophysiology of the condition is presented. The importance of monitoring the serum for beta subunit human chorionic gonadotrophin (HCG) is emphasised.

  8. Implantable Drug Dispenser

    NASA Technical Reports Server (NTRS)

    Collins, E. R. J.

    1983-01-01

    Drugs such as insulin are injected as needed directly into bloodstream by compact implantable dispensing unit. Two vapor cavities produce opposing forces on drug-chamber diaphragm. Heaters in cavities allow control of direction and rate of motion of bellows. Dispensing capsule fitted with coil so batteries can be recharged by induction.

  9. Remote actuated valve implant

    DOEpatents

    McKnight, Timothy E; Johnson, Anthony; Moise, Jr., Kenneth J; Ericson, Milton Nance; Baba, Justin S; Wilgen, John B; Evans, III, Boyd McCutchen

    2014-02-25

    Valve implant systems positionable within a flow passage, the systems having an inlet, an outlet, and a remotely activatable valve between the inlet and outlet, with the valves being operable to provide intermittent occlusion of the flow path. A remote field is applied to provide thermal or magnetic activation of the valves.

  10. Implantable electrical device

    NASA Technical Reports Server (NTRS)

    Jhabvala, M. D. (Inventor)

    1982-01-01

    A fully implantable and self contained device is disclosed composed of a flexible electrode array for surrounding damaged nerves and a signal generator for driving the electrode array with periodic electrical impulses of nanoampere magnitude to induce regeneration of the damaged nerves.

  11. Implantable Impedance Plethysmography

    PubMed Central

    Theodor, Michael; Ruh, Dominic; Ocker, Martin; Spether, Dominik; Förster, Katharina; Heilmann, Claudia; Beyersdorf, Friedhelm; Manoli, Yiannos; Zappe, Hans; Seifert, Andreas

    2014-01-01

    We demonstrate by theory, as well as by ex vivo and in vivo measurements that impedance plethysmography, applied extravascularly directly on large arteries, is a viable method for monitoring various cardiovascular parameters, such as blood pressure, with high accuracy. The sensor is designed as an implant to monitor cardiac events and arteriosclerotic progression over the long term. PMID:25123467

  12. The reverse zygomatic implant: a new implant for maxillofacial reconstruction.

    PubMed

    Dawood, Andrew; Collier, Jonathan; Darwood, Alastair; Tanner, Susan

    2015-01-01

    This case report describes the rehabilitation of a patient who had been treated with a hemimaxillectomy, reconstruction with a latissimus dorsi vascularized free flap, and radiotherapy for carcinoma of the sinus some years previously. Limited jaw opening, difficult access through the flap to the bony site, and the very small amount of bone available in which to anchor the implant inspired the development and use of a new "reverse zygomatic" implant. For this treatment, site preparation and implant insertion were accomplished using an extraoral approach. The implant was used along with two other conventional zygomatic implants to provide support for a milled titanium bar and overdenture to rehabilitate the maxilla. Two years later, the patient continues to enjoy a healthy reconstruction. The reverse zygomatic implant appears to show promise as a useful addition to the implant armamentarium for the treatment of the patient undergoing maxillectomy. PMID:26574864

  13. Haemocompatibility optimisation of implants by hybrid structuring.

    PubMed

    Bolz, A; Schaldach, M

    1993-07-01

    State of the art in biomaterial research and implant design is a compromise between functionality and biocompatibility. Consequently, results often have disadvantages with respect to both aspects. With regard to biocompatibility, the activation of the clotting system by alloplastic materials is of great significance, because it necessitates anticoagulant therapy. Further improvements in implant technology require an understanding of the interactions between blood and implants. Therefore a microscopic model of thrombogenesis at alloplastic surfaces is briefly presented, relating thrombogenicity of a material to the electronic structure of its surface. The electronic requirements for high haemocompatibility, which result from this model (especially a low band-gap density of states and a high surface conductivity) are fulfilled by an amorphous alloy of silicon and carbon (a-SiC:H). The advantage of amorphous materials is that they do not obey stoichiometric rules. Thus they allow a continuous adjustment of the electronic parameters without fundamental changes in their mechanical and chemical properties. The theoretical results were checked in vitro by total internal reflection intrinsic fluorescence (TIRIF) spectroscopy as well as thrombelastography experiments (TEG). In comparison with conventional materials such as titanium or LTI carbon, the TEG-clotting time of a-SiC:H-coatings was prolonged by in excess of 200 per cent. As a consequence, a-SiC:H is well suited as a haemocompatible coating material for hybrid structuring of cardiovascular implants.

  14. Approaches to USJ Formation Beyond Molecular Implantation

    SciTech Connect

    Hatem, C.; Renau, A.; Godet, L.; Kontos, A.; Papasouliotis, G.; England, J.; Arevalo, E.

    2008-11-03

    As junction depth requirements approach sub 10 nm and the sensitivity to residual implant damage continues to increase, the capability to produce abrupt, shallow profiles while maintaining low residual damage becomes a difficult challenge. Implantation induced amorphization has been widely applied to reduce channeling tails of implanted dopant profiles for integrated circuit manufacturing. This has been required to meet aggressive junction depth targets. The problem, however, is that pre-amorphization creates high defect densities that remain near the former amorphous-crystalline interface post anneal. These end of range (EOR) defects become of greater concern as the industry begins to move towards millisecond anneal technologies. Millisecond anneal, while capable of close to diffusionless activation and abrupt junctions, has caused concern for its inability to fully repair these EOR defects. There has been a recent focus on removing traditional PAI through molecular implantation with limited success. Towards this end we have investigated alternative techniques to reduce EOR damage while maintaining the junction depth, sheet resistance and abruptness. Here we describe the results of two of these techniques. The subsequent reduction in EOR through the use of each process and the resultant Rs, junction depth and abruptness are detailed.

  15. Magnetic insertion system for flexible electrode implantation.

    PubMed

    Jaroch, David B; Ward, Matthew P; Chow, Eric Y; Rickus, Jenna L; Irazoqui, Pedro P

    2009-10-15

    Chronic recording electrodes are a vital tool for brain research and neural prostheses. Despite decades of advances in recording technology, probe structures and implantation methods have changed little over time. Then as now, compressive insertion methods require probes to be constructed from hard, stiff materials, such as silicon, and contain a large diameter shank to penetrate the brain, particularly for deeper structures. The chronic presence of these probes results in an electrically isolating glial scar, degrading signal quality over time. This work demonstrates a new magnetic tension-based insertion mechanism that allows for the use of soft, flexible, and thinner probe materials, overcoming the materials limitations of modern electrodes. Probes are constructed from a sharp magnetic tip attached to a flexible tether. A pulsed magnetic field is generated in a coil surrounding a glass pipette containing the electrode. The applied field pulls the electrode tip forward, accelerating the probe into the neural tissue with a penetration depth that is calibrated against the charge voltage. Mathematical modeling and agar gel insertion testing demonstrate that the electrode can be implanted to a predictable depth given system specific parameters. Trial rodent implantations resulted in discernible single-unit activity on one of the probes. The current prototype demonstrates the feasibility of a tension based, magnetically driven implantation system and opens the door to a wide variety of new minimally invasive probe materials and configurations.

  16. Optimal restoration of dental esthetics and function with advanced implant-supported prostheses: a clinical report.

    PubMed

    Meulen, Peter van der; Linden, Wynand van der; Eeden, Ronnie van

    2012-07-01

    For more than 25 years, computer-aided design and computer-aided manufacturing (CAD/CAM) technology has been used in implant restorative dentistry. Today this technology offers a means of milling titanium frameworks that fit dental implants accurately. This report presents a restoratively driven protocol employing advanced implant restorative and surgical techniques. Treatment of a patient with advanced periodontitis with extensive loss of hard and soft tissues is presented. After extraction of the patient's remaining hopeless teeth, dental implants were placed, along with interim, fixed-margin abutments and abutment protection caps. Two days later, acrylic resin fixed-interim prostheses restored the patient's esthetics and partial masticatory function. After implant osseointegration, maxillary, and mandibular frameworks for definitive prostheses were milled from Ti alloy, using one specific CAD/CAM technology. The benefits of this technology are also discussed.

  17. Corynebacterium glutamicum Is Equipped with Four Secondary Carriers for Compatible Solutes: Identification, Sequencing, and Characterization of the Proline/Ectoine Uptake System, ProP, and the Ectoine/Proline/Glycine Betaine Carrier, EctP

    PubMed Central

    Peter, Heidi; Weil, Brita; Burkovski, Andreas; Krämer, Reinhard; Morbach, Susanne

    1998-01-01

    Gram-positive soil bacterium Corynebacterium glutamicum uses the compatible solutes glycine betaine, proline, and ectoine for protection against hyperosmotic shock. Osmoregulated glycine betaine carrier BetP and proline permease PutP have been previously characterized; we have identified and characterized two additional osmoregulated secondary transporters for compatible solutes in C. glutamicum, namely, the proline/ectoine carrier, ProP, and the ectoine/glycine betaine/proline carrier, EctP. A ΔbetP ΔputP ΔproP ΔectP mutant was unable to respond to hyperosmotic stress, indicating that no additional uptake system for these compatible solutes is present. Osmoregulated ProP consists of 504 residues and preferred proline (Km, 48 μM) to ectoine (Km, 132 μM). The proP gene could not be expressed from its own promoter in C. glutamicum; however, expression was observed in Escherichia coli. ProP belongs to the major facilitator superfamily, whereas EctP, together with the betaine carrier, BetP, is a member of a newly established subfamily of the sodium/solute symporter superfamily. The constitutively expressed ectP codes for a 615-residue transporter. EctP preferred ectoine (Km, 63 μM) to betaine (Km, 333 μM) and proline (Km, 1,200 μM). Its activity was regulated by the external osmolality. The related betaine transporter, BetP, could be activated directly by altering the membrane state with local anesthetics, but this was not the case for EctP. Furthermore, the onset of osmotic activation was virtually instantaneous for BetP, whereas it took about 10 s for EctP. PMID:9811661

  18. The Nuclear Energy Advanced Modeling and Simulation Enabling Computational Technologies FY09 Report

    SciTech Connect

    Diachin, L F; Garaizar, F X; Henson, V E; Pope, G

    2009-10-12

    In this document we report on the status of the Nuclear Energy Advanced Modeling and Simulation (NEAMS) Enabling Computational Technologies (ECT) effort. In particular, we provide the context for ECT In the broader NEAMS program and describe the three pillars of the ECT effort, namely, (1) tools and libraries, (2) software quality assurance, and (3) computational facility (computers, storage, etc) needs. We report on our FY09 deliverables to determine the needs of the integrated performance and safety codes (IPSCs) in these three areas and lay out the general plan for software quality assurance to meet the requirements of DOE and the DOE Advanced Fuel Cycle Initiative (AFCI). We conclude with a brief description of our interactions with the Idaho National Laboratory computer center to determine what is needed to expand their role as a NEAMS user facility.

  19. The development of the Nucleus Freedom Cochlear implant system.

    PubMed

    Patrick, James F; Busby, Peter A; Gibson, Peter J

    2006-12-01

    Cochlear Limited (Cochlear) released the fourth-generation cochlear implant system, Nucleus Freedom, in 2005. Freedom is based on 25 years of experience in cochlear implant research and development and incorporates advances in medicine, implantable materials, electronic technology, and sound coding. This article presents the development of Cochlear's implant systems, with an overview of the first 3 generations, and details of the Freedom system: the CI24RE receiver-stimulator, the Contour Advance electrode, the modular Freedom processor, the available speech coding strategies, the input processing options of Smart Sound to improve the signal before coding as electrical signals, and the programming software. Preliminary results from multicenter studies with the Freedom system are reported, demonstrating better levels of performance compared with the previous systems. The final section presents the most recent implant reliability data, with the early findings at 18 months showing improved reliability of the Freedom implant compared with the earlier Nucleus 3 System. Also reported are some of the findings of Cochlear's collaborative research programs to improve recipient outcomes. Included are studies showing the benefits from bilateral implants, electroacoustic stimulation using an ipsilateral and/or contralateral hearing aid, advanced speech coding, and streamlined speech processor programming.

  20. Cochlear Implantation, Enhancements, Transhumanism and Posthumanism: Some Human Questions.

    PubMed

    Lee, Joseph

    2016-02-01

    Biomedical engineering technologies such as brain-machine interfaces and neuroprosthetics are advancements which assist human beings in varied ways. There are exciting yet speculative visions of how the neurosciences and bioengineering may influence human nature. However, these could be preparing a possible pathway towards an enhanced and even posthuman future. This article seeks to investigate several ethical themes and wider questions of enhancement, transhumanism and posthumanism. Four themes of interest are: autonomy, identity, futures, and community. Three larger questions can be asked: will everyone be enhanced? Will we be "human" if we are not, one day, transhuman? Should we be enhanced or not? The article proceeds by concentrating on a widespread and sometimes controversial application: the cochlear implant, an auditory prosthesis implanted into Deaf patients. Cochlear implantation and its reception in both the deaf and hearing communities have a distinctive moral discourse, which can offer surprising insights. The paper begins with several points about the enhancement of human beings, transhumanism's reach beyond the human, and posthuman aspirations. Next it focuses on cochlear implants on two sides. Firstly, a shorter consideration of what technologies may do to humans in a transhumanist world. Secondly, a deeper analysis of cochlear implantation's unique socio-political movement, its ethical explanations and cultural experiences linked with pediatric cochlear implantation-and how those wary of being thrust towards posthumanism could marshal such ideas by analogy. As transhumanism approaches, the issues and questions merit continuing intense analysis.

  1. A Threat to Autonomy? The Intrusion of Predictive Brain Implants

    PubMed Central

    Gilbert, Frederic

    2015-01-01

    The world's first-in-human clinical trial using invasive intelligent brain devices—devices that predict specific neuronal events directly to the implanted person—has been completed with significant success. Predicting brain activity before specific outcomes occur brings a raft of unprecedented applications, especially when implants offer advice on how to respond to the neuronal events forecasted. Although these novel predictive and advisory implantable devices offer great potential to positively affect patients following surgery by enhancing quality of life (e.g., provide control over symptoms), substantial ethical concerns remain. The invasive nature of these novel devices is not unique; however, the inclusion of predictive and advisory functionalities within the implants, involving permanent monitoring of brain activity in real time, raises new ethical issues to explore, especially in relation to concerns for patient autonomy. What might be the effects of ongoing monitoring of predictive and advisory brain technologies on a patient's postoperative sense of autonomy? The role played by predictive and advisory implantable brain devices on patient's feelings of autonomy following surgery is completely unknown. The first section of this article addresses this shortcoming by reporting on a pilot study that we conducted with one of the patients implanted with one of these novel brain devices. The second section examines how overreliance on predictive and advisory brain technologies may threaten patients' autonomy. The third section looks into ethical problems concerning how devices delivering automated therapeutic responses might, hypothetically speaking, be used to monitor and control individual's autonomy through inhibition of undesirable behaviors. PMID:26740906

  2. Prosthetic rehabilitation with an implant-supported fixed prosthesis using computer-aided design and computer-aided manufacturing dental technology for a patient with a mandibulectomy: A clinical report.

    PubMed

    Yoon, Hyung-In; Han, Jung-Suk

    2016-02-01

    The fabrication of dental prostheses with computer-aided design and computer-aided manufacturing shows acceptable marginal fits and favorable treatment outcomes. This clinical report describes the management of a patient who had undergone a mandibulectomy and received an implant-supported fixed prosthesis by using additive manufacturing for the framework and subtractive manufacturing for the monolithic zirconia restorations.

  3. Ect2/Pbl Acts via Rho and Polarity Proteins to Direct the Assembly of an Isotropic Actomyosin Cortex upon Mitotic Entry

    PubMed Central

    Rosa, André; Vlassaks, Evi; Pichaud, Franck; Baum, Buzz

    2015-01-01

    Summary Entry into mitosis is accompanied by profound changes in cortical actomyosin organization. Here, we delineate a pathway downstream of the RhoGEF Pbl/Ect2 that directs this process in a model epithelium. Our data suggest that the release of Pbl/Ect2 from the nucleus at mitotic entry drives Rho-dependent activation of Myosin-II and, in parallel, induces a switch from Arp2/3 to Diaphanous-mediated cortical actin nucleation that depends on Cdc42, aPKC, and Par6. At the same time, the mitotic relocalization of these apical protein complexes to more lateral cell surfaces enables Cdc42/aPKC/Par6 to take on a mitosis-specific function—aiding the assembly of a relatively isotropic metaphase cortex. Together, these data reveal how the repolarization and remodeling of the actomyosin cortex are coordinated upon entry into mitosis to provide cells with the isotropic and rigid form they need to undergo faithful chromosome segregation and division in a crowded tissue environment. PMID:25703349

  4. Pediatric Cochlear Implantation: Why Do Children Receive Implants Late?

    PubMed Central

    Ham, Julia; Whittingham, JoAnne

    2015-01-01

    Objectives: Early cochlear implantation has been widely promoted for children who derive inadequate benefit from conventional acoustic amplification. Universal newborn hearing screening has led to earlier identification and intervention, including cochlear implantation in much of the world. The purpose of this study was to examine age and time to cochlear implantation and to understand the factors that affected late cochlear implantation in children who received cochlear implants. Design: In this population-based study, data were examined for all children who underwent cochlear implant surgery in one region of Canada from 2002 to 2013. Clinical characteristics were collected prospectively as part of a larger project examining outcomes from newborn hearing screening. For this study, audiologic details including age and severity of hearing loss at diagnosis, age at cochlear implant candidacy, and age at cochlear implantation were documented. Additional detailed medical chart information was extracted to identify the factors associated with late implantation for children who received cochlear implants more than 12 months after confirmation of hearing loss. Results: The median age of diagnosis of permanent hearing loss for 187 children was 12.6 (interquartile range: 5.5, 21.7) months, and the age of cochlear implantation over the 12-year period was highly variable with a median age of 36.2 (interquartile range: 21.4, 71.3) months. A total of 118 (63.1%) received their first implant more than 12 months after confirmation of hearing loss. Detailed analysis of clinical profiles for these 118 children revealed that late implantation could be accounted for primarily by progressive hearing loss (52.5%), complex medical conditions (16.9%), family indecision (9.3%), geographical location (5.9%), and other miscellaneous known (6.8%) and unknown factors (8.5%). Conclusions: This study confirms that despite the trend toward earlier implantation, a substantial number of children

  5. Piezosurgery in implant dentistry

    PubMed Central

    Stübinger, Stefan; Stricker, Andres; Berg, Britt-Isabelle

    2015-01-01

    Piezosurgery, or the use of piezoelectric devices, is being applied increasingly in oral and maxillofacial surgery. The main advantages of this technique are precise and selective cuttings, the avoidance of thermal damage, and the preservation of soft-tissue structures. Through the application of piezoelectric surgery, implant-site preparation, bone grafting, sinus-floor elevation, edentulous ridge splitting or the lateralization of the inferior alveolar nerve are very technically feasible. This clinical overview gives a short summary of the current literature and outlines the advantages and disadvantages of piezoelectric bone surgery in implant dentistry. Overall, piezoelectric surgery is superior to other methods that utilize mechanical instruments. Handling of delicate or compromised hard- and soft-tissue conditions can be performed with less risk for the patient. With respect to current and future innovative surgical concepts, piezoelectric surgery offers a wide range of new possibilities to perform customized and minimally invasive osteotomies. PMID:26635486

  6. Sterilisation of implantable devices.

    PubMed

    Matthews, I P; Gibson, C; Samuel, A H

    1994-01-01

    The pathogenesis and rates of infection associated with the use of a wide variety of implantable devices are described. The multi-factorial nature of post-operative periprosthetic infection is outlined and the role of sterilisation of devices is explained. The resistance of bacterial spores is highlighted as a problem and a full description is given of the processes of sterilisation by heat, steam, ethylene oxide, low temperature steam and formaldehyde, ionising radiation and liquid glutaraldehyde. Sterility assurance and validation are discussed in the context of biological indicators and physical/chemical indicators. Adverse effects upon the material composition of devices and problems of process control are listed. Finally, possible optimisations of the ethylene oxide process and their potential significance to the field of sterilisation of implants is explored. PMID:10172076

  7. CUSTOM-FIT RADIOLUCENT CRANIAL IMPLANTS FOR NEUROPHYSIOLOGICAL RECORDING AND STIMULATION

    PubMed Central

    Mulliken, Grant H; Bichot, Narcisse P; Ghadooshahy, Azriel; Sharma, Jitendra; Kornblith, Simon; Philcock, Michael; Desimone, Robert

    2015-01-01

    Background Recording and manipulating neural activity in awake behaving animal models requires long-term implantation of cranial implants that must address a variety of design considerations, which include preventing infection, minimizing tissue damage, mechanical strength of the implant, and MRI compatibility. New Method Here we address these issues by designing legless, custom-fit cranial implants using structural MRI-based reconstruction of the skull and that are made from carbon-reinforced PEEK. Results We report several novel custom-fit radiolucent implant designs, which include a legless recording chamber, a legless stimulation chamber, a multi-channel microdrive and a head post. The fit to the skull was excellent in all cases, with no visible gaps between the base of the implants and the skull. The wound margin was minimal in size and showed no sign of infection or skin recession. Comparison with Existing Methods Cranial implants used for neurophysiological investigation in awake behaving animals often employ methyl methacrylate (MMA) to serve as a bonding agent to secure the implant to the skull. Other designs rely on radially extending legs to secure the implant. Both of these methods have significant drawbacks. MMA is toxic to bone and frequently leads to infection while radially extending legs cause the skin to recede away from the implant, ultimately exposing bone and proliferating granulation tissue. Conclusions These radiolucent implants constitute a set of technologies suitable for reliable long-term recording, which minimize infection and tissue damage. PMID:25542350

  8. Instrumented knee joint implants: innovations and promising concepts.

    PubMed

    Torrão, João N D; Dos Santos, Marco P Soares; Ferreira, Jorge A F

    2015-01-01

    This article focuses on in vivo implementations of instrumented knee implants and recent prototypes with highly innovative potential. An in-depth analysis of the evolution of these systems was conducted, including three architectures developed by two research teams for in vivo operation that were implanted in 13 patients. The specifications of their various subsystems: sensor/transducers, power management, communication and processing/control units are presented, and their features are compared. These systems were designed to measure biomechanical quantities to further assist in rehabilitation and physical therapy, to access proper implant placement and joint function and to help predicting aseptic loosening. Five prototype systems that aim to improve their operation, as well as include new abilities, are also featured. They include technology to assist proper ligament tensioning and ensure self-powering. One can conclude that the concept of instrumented active knee implant seems the most promising trend for improving the outcomes of knee replacements.

  9. Cochlear implants and the deaf child: a nursing perspective.

    PubMed

    Russell, K E; Coffin, C; Kenna, M

    1999-01-01

    Cochlear implants are no longer considered new or experimental technology and are available for children with profound sensorineural hearing loss. Pediatric cochlear implantation requires a multidisciplinary team approach with contributions from surgeons, audiologists, speech-language pathologists, psychologists, nurses, special educators, and parents. The decision to perform cochlear implantation in children must be seriously considered. Some in the deaf community voice strong objections to the procedure. Additionally, it requires an enormous commitment on the part of the family and the health care system in both personal and financial terms. The surgery has some risks, and the rehabilitation period is lengthy. Outcomes are variable, and many factors play a role in a child's successful use of implants. Nonetheless, gradual, steady improvement in speech perception, speech production, and language typically occurs. The approach of Children's Hospital in Boston to the assessment, the surgical procedure, and follow-up is detailed here.

  10. Final restoration of implants with a hybrid ceramic superstructure.

    PubMed

    Kurbad, Andreas

    2016-01-01

    The use of materials with elastic properties for the fabrication of dental implant superstructures seems to be a promising way to reduce the functional occlusal forces on implants. Vita Enamic (Vita Zahnfabrik, Bad Säckingen), a hybrid ceramic material for CAD/CAM technology, is available in a special form that can be relatively easily combined with titanium (Ti) base connectors for the fabrication of abutment crowns and mesostructures. Thus, an easily manageable method is available for reducing peak loads on dental implant fixtures. Representative cases are presented to demonstrate the clinical workflows for a single- element solution (Ti base) and two-element solution (Ti base with mesostructure) for implant-supported crowns. PMID:27644182

  11. A novel strategy for long-term implantable artificial pancreas.

    PubMed

    Ricotti, Leonardo; Assaf, Tareq; Menciassi, Arianna; Dario, Paolo

    2011-01-01

    Technology has recently changed type 1 diabetes treatment by introducing several advancements able to improve patients' quality of life. However, despite of several decades of research efforts, the dream of a fully-automated implanted artificial pancreas is quite far from its realization. The need for periodically restoring the implanted battery charge and refilling the implanted insulin reservoir are the main issues, for which invasive surgery, transcutaneous catheters or external portable devices are presently the only solutions. In this paper we propose a novel approach to these issues, describing a totally implanted closed-loop artificial pancreas with a wireless battery charger and a non-invasive strategy for insulin refilling, based on sensorized swallowable "insulin carrier" capsules. Such system has the potential to represent a final solution for diabetes treatment, by fully restoring patients' quality of life.

  12. Industrial applications of ion implantation into metal surfaces

    SciTech Connect

    Williams, J.M.

    1987-07-01

    The modern materials processing technique, ion implantation, has intriguing and attractive features that stimulate the imaginations of scientists and technologists. Success of the technique for introducing dopants into semiconductors has resulted in a stable and growing infrastructure of capital equipment and skills for use of the technique in the economy. Attention has turned to possible use of ion implantation for modification of nearly all surface related properties of materials - optical, chemical and corrosive, tribological, and several others. This presentation provides an introduction to fundamental aspects of equipment, technique, and materials science of ion implantation. Practical and economic factors pertaining to the technology are discussed. Applications and potential applications are surveyed. There are already available a number of ion-implanted products, including ball-and-roller bearings and races, punches-and-dies, injection screws for plastics molding, etc., of potential interest to the machine tool industry.

  13. SEM analysis of ion implanted SiC

    NASA Astrophysics Data System (ADS)

    Malherbe, Johan B.; van der Berg, N. G.; Botha, A. J.; Friedland, E.; Hlatshwayo, T. T.; Kuhudzai, R. J.; Wendler, E.; Wesch, W.; Chakraborty, P.; da Silveira, E. F.

    2013-11-01

    SiC is a material used in two future energy production technologies, firstly as a photovoltaic layer to harness the UV spectrum in high efficient power solar cells, and secondly as a diffusion barrier material for radioactive fission products in the fuel elements of the next generation of nuclear power plants. For both applications, there is an interest in the implantation of reactive and non-reactive ions into SiC and their effects on the properties of the SiC. In this study 360 keV Ag+, I+ and Xe+ ions were separately implanted into 6H-SiC and in polycrystalline SiC at various substrate temperatures. The implanted samples were also annealed in vacuum at temperatures ranging from 900 °C to 1600 °C for various times. In recent years, there had been significant advances in scanning electron microscopy (SEM) with the introduction of an in-lens detector combined with field emission electron guns. This allows defects in solids, such as radiation damage created by the implanted ions, to be detected with SEM. Cross-sectional SEM images of 6H-SiC wafers implanted with 360 keV Ag+ ions at room temperature and at 600 °C and then vacuum annealed at different temperatures revealed the implanted layers and their thicknesses. A similar result is shown of 360 keV I+ ions implanted at 600 °C into 6H-SiC and annealed at 1600 °C. The 6H-SiC is not amorphized but remained crystalline when implanting at 600 °C. There are differences in the microstructure of 6H-SiC implanted with silver at the two temperatures as well as with reactive iodine ions. Voids (bubbles) are created in the implanted layers into which the precipitation of silver and iodine can occur after annealing of the samples. The crystallinity of the substrate via implantation temperature caused differences in the distribution and size of the voids. Implantation of xenon ions in polycrystalline SiC at 350 °C does not amorphize the substrate as is the case with room temperature heavy ion bombardment. Subsequent

  14. The Aula EspaZio Gela and the Master of Space Science and Technology in the Universidad Del País Vasco (University of the Basque Country)

    ERIC Educational Resources Information Center

    Sánchez-Lavega, Agustín; Pérez-Hoyos, Santiago; Hueso, Ricardo; del Río-Gaztelurrutia, Teresa; Oleaga, Alberto

    2014-01-01

    We present the Aula EspaZio Gela, a facility dedicated to teaching Space Science and Technology at the master and doctorate level at the University of the Basque Country (Spain), and to promoting the development of this field in both public and private sectors. The one-year master's degree in Space Science and Technology (60 ECTS (European…

  15. Implants for cranioplasty.

    PubMed

    Gladstone, H B; McDermott, M W; Cooke, D D

    1995-04-01

    As long as there have been skull defects, there has been a recognized need to cover them in some way. Cranioplasty is the surgical correction of skull defects. The two major purposes of performing a cranioplasty are to protect the brain and to provide reasonable cosmesis. The two physical requirements of the implant are strength and malleability. Originally, foreign materials such as precious metals were used. Autogenous bone grafts have also achieved successful results. Over the past quarter-century, the popularization of acrylics and radiolucent metals has favored them over bone because of their ease of use, the absence of need to harvest donor bone, and, particularly, bone's tendency to resorb or scar. Yet foreign materials can cause excessive inflammation, producing a synovial membrane at the interface between the host bone and cranioplasty construct, increasing the risk of infection. Currently, hydroxyapatite-based ceramics, which may induce bone growth into the implant, are increasingly being used. Future applications will include antibiotic-impregnated implants and computer-generated models to improve the precision of cranioplasty fit and cosmesis.

  16. [Neurotology and cochlear implants].

    PubMed

    Merchán, Miguel A

    2015-05-01

    In this review we analyse cochlear implantation in terms of the fundamental aspects of the functioning of the auditory system. Concepts concerning neuronal plasticity applied to electrical stimulation in perinatal and adult deep hypoacusis are reviewed, and the latest scientific bases that justify early implantation following screening for congenital deafness are discussed. Finally, this review aims to serve as an example of the importance of fostering the sub-specialty of neurotology in our milieu, with the aim of bridging some of the gaps between specialties and thus improving both the knowledge in the field of research on auditory pathologies and in the screening of patients. The objectives of this review, targeted above all towards specialists in the field of otorhinolaryngology, are to analyse some significant neurological foundations in order to reach a better understanding of the clinical events that condition the indications and the rehabilitation of patients with cochlear implants, as well as to use this means to foster the growth of the sub-specialty of neurotology.

  17. Engineering single photon emitters by ion implantation in diamond

    PubMed Central

    Naydenov, B.; Kolesov, R.; Batalov, A.; Meijer, J.; Pezzagna, S.; Rogalla, D.; Jelezko, F.; Wrachtrup, J.

    2009-01-01

    Diamond provides unique technological platform for quantum technologies including quantum computing and communication. Controlled fabrication of optically active defects is a key element for such quantum toolkit. Here we report the production of single color centers emitting in the blue spectral region by high energy implantation of carbon ions. We demonstrate that single implanted defects show sub-poissonian statistics of the emitted photons and can be explored as single photon source in quantum cryptography. Strong zero phonon line at 470.5 nm allows unambiguous identification of this defect as interstitial-related TR12 color center. PMID:19956415

  18. Engineering single photon emitters by ion implantation in diamond.

    PubMed

    Naydenov, B; Kolesov, R; Batalov, A; Meijer, J; Pezzagna, S; Rogalla, D; Jelezko, F; Wrachtrup, J

    2009-11-01

    Diamond provides unique technological platform for quantum technologies including quantum computing and communication. Controlled fabrication of optically active defects is a key element for such quantum toolkit. Here we report the production of single color centers emitting in the blue spectral region by high energy implantation of carbon ions. We demonstrate that single implanted defects show sub-poissonian statistics of the emitted photons and can be explored as single photon source in quantum cryptography. Strong zero phonon line at 470.5 nm allows unambiguous identification of this defect as interstitial-related TR12 color center. PMID:19956415

  19. Engineering single photon emitters by ion implantation in diamond

    NASA Astrophysics Data System (ADS)

    Naydenov, B.; Kolesov, R.; Batalov, A.; Meijer, J.; Pezzagna, S.; Rogalla, D.; Jelezko, F.; Wrachtrup, J.

    2009-11-01

    Diamond provides unique technological platform for quantum technologies including quantum computing and communication. Controlled fabrication of optically active defects is a key element for such quantum toolkit. Here we report the production of single color centers emitting in the blue spectral region by high energy implantation of carbon ions. We demonstrate that single implanted defects show sub-poissonian statistics of the emitted photons and can be explored as single photon source in quantum cryptography. Strong zero phonon line at 470.5 nm allows unambiguous identification of this defect as interstitial-related TR12 color center.

  20. Engineering single photon emitters by ion implantation in diamond.

    PubMed

    Naydenov, B; Kolesov, R; Batalov, A; Meijer, J; Pezzagna, S; Rogalla, D; Jelezko, F; Wrachtrup, J

    2009-11-01

    Diamond provides unique technological platform for quantum technologies including quantum computing and communication. Controlled fabrication of optically active defects is a key element for such quantum toolkit. Here we report the production of single color centers emitting in the blue spectral region by high energy implantation of carbon ions. We demonstrate that single implanted defects show sub-poissonian statistics of the emitted photons and can be explored as single photon source in quantum cryptography. Strong zero phonon line at 470.5 nm allows unambiguous identification of this defect as interstitial-related TR12 color center.

  1. Advanced maintenance, inspection & repair technology for nuclear power plants

    SciTech Connect

    Hinton, B.M.

    1994-12-31

    Maintenance, inspection, and repair technology for nuclear power plants is outlined. The following topics are discussed: technology for reactor systems, reactor refueling bridge, fuel inspection system, fuel shuffling software, fuel reconstitution, CEA/RCCA/CRA inspection, vessel inspection capabilities, CRDM inspection and repair, reactor internals inspection and repair, stud tensioning system, stud/nut cleaning system, EDM machining technology, MI Cable systems, core exit T/C nozzle assemblies, technology for steam generators, genesis manipulator systems, ECT, UT penetrant inspections, steam generator repair and cleaning systems, technology for balance of plant, heat exchangers, piping and weld inspections, and turbogenerators.

  2. Temperature dependent surface modification of T91 steel under 3.25 MeV Fe-ion implantation

    NASA Astrophysics Data System (ADS)

    Zhu, Huiping; Wang, Zhiguang; Cui, Minghuan; Li, Bingsheng; Gao, Xing; Sun, Jianrong; Yao, Cunfeng; Wei, Kongfang; Shen, Tielong; Pang, Lilong; Zhu, Yabin; Li, Yuanfei; Wang, Ji; Xie, Erqing

    2015-01-01

    Ion implantation is an established technique for modifying the surface properties of a wide range of materials. In this research, temperature dependent surface modification induced by Fe-ion implantation in T91 steel was investigated. The T91 samples were implanted with 3.25 MeV Fe-ions to fluence of 1.7 × 1016 ions/cm2 at room temperature, 300 and 450 °C, respectively. After implantation, the T91 samples were characterized by means of positron annihilation Doppler broadening spectroscopy (PADBS) and nano-indention technology (NIT). It was found that the concentration of open-volume defects in T91 samples decreased with increasing implantation temperature. From NIT analysis, it was found that all the samples were hardened after implantation and the hardness of the implanted T91 samples increased with increasing implantation temperature.

  3. Sub-meninges implantation reduces immune response to neural implants.

    PubMed

    Markwardt, Neil T; Stokol, Jodi; Rennaker, Robert L

    2013-04-15

    Glial scar formation around neural interfaces inhibits their ability to acquire usable signals from the surrounding neurons. To improve neural recording performance, the inflammatory response and glial scarring must be minimized. Previous work has indicated that meningeally derived cells participate in the immune response, and it is possible that the meninges may grow down around the shank of a neural implant, contributing to the formation of the glial scar. This study examines whether the glial scar can be reduced by placing a neural probe completely below the meninges. Rats were implanted with sets of loose microwire implants placed either completely below the meninges or implanted conventionally with the upper end penetrating the meninges, but not attached to the skull. Histological analysis was performed 4 weeks following surgical implantation to evaluate the glial scar. Our results found that sub-meninges implants showed an average reduction in reactive astrocyte activity of 63% compared to trans-meninges implants. Microglial activity was also reduced for sub-meninges implants. These results suggest that techniques that isolate implants from the meninges offer the potential to reduce the encapsulation response which should improve chronic recording quality and stability.

  4. Sub-meninges Implantation Reduces Immune Response to Neural Implants

    PubMed Central

    Markwardt, Neil T.; Stokol, Jodi; Rennaker, Robert L.

    2013-01-01

    Glial scar formation around neural interfaces inhibits their ability to acquire usable signals from the surrounding neurons. To improve neural recording performance, the inflammatory response and glial scarring must be minimized. Previous work has indicated that meningeally derived cells participate in the immune response, and it is possible that the meninges may grow down around the shank of a neural implant, contributing to the formation of the glial scar. This study examines whether the glial scar can be reduced by placing a neural probe completely below the meninges. Rats were implanted with sets of loose microwire implants placed either completely below the meninges or implanted conventionally with the upper end penetrating the meninges, but not attached to the skull. Histological analysis was performed 4 weeks following surgical implantation to evaluate the glial scar. Our results found that sub-meninges implants showed an average reduction in reactive astrocyte activity of 63% compared to trans-meninges implants. Microglial activity was also reduced for sub-meninges implants. These results suggest that techniques that isolate implants from the meninges offer the potential to reduce the encapsulation response which should improve chronic recording quality and stability. PMID:23370311

  5. Automatic frequency controller for power amplifiers used in bio-implanted applications: issues and challenges.

    PubMed

    Hannan, Mahammad A; Hussein, Hussein A; Mutashar, Saad; Samad, Salina A; Hussain, Aini

    2014-01-01

    With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil's mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning the progress of

  6. Automatic frequency controller for power amplifiers used in bio-implanted applications: issues and challenges.

    PubMed

    Hannan, Mahammad A; Hussein, Hussein A; Mutashar, Saad; Samad, Salina A; Hussain, Aini

    2014-12-11

    With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil's mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning the progress of

  7. Automatic Frequency Controller for Power Amplifiers Used in Bio-Implanted Applications: Issues and Challenges

    PubMed Central

    Hannan, Mahammad A.; Hussein, Hussein A.; Mutashar, Saad; Samad, Salina A.; Hussain, Aini

    2014-01-01

    With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil's mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning the progress of

  8. [Professional occupation after cochlear implantation].

    PubMed

    Kós, Maria-Izabel; Degive, Colette; Boëx, Colette; Maire, Raphaël; Guyot, Jean-Philippe

    2006-10-01

    This study verifies whether cochlear implants helps deaf adults to maintain or develop their professional occupations. Sixty-seven patients received a questionnaire concerning their professional activities before and after implantation. At the time of implantation 34 were professionally active. After the implantation 29 remained active, 4 of them reporting positive developments in their careers. Five patients became inactive. The previously inactive patients remained inactive. There was no difference in auditory performances between professionally active or inactive patients. Cochlear implants enable most implanted adults to maintain and even progress in their professions. However, deafness still represents an obstacle to social integration as inactive patients who searched for a job were rejected after the job interviews. PMID:17076153

  9. BF{sub 3} PIII modeling: Implantation, amorphisation and diffusion

    SciTech Connect

    Essa, Z.; Cristiano, F.; Spiegel, Y.; Boulenc, P.; Qiu, Y.; Quillec, M.; Taleb, N.; Burenkov, A.; Hackenberg, M.; Bedel-Pereira, E.; Mortet, V.; Torregrosa, Frank; Tavernier, C.

    2012-11-06

    In the race for highly doped ultra-shallow junctions (USJs) in complementary metal oxide semi-conductor (CMOS) technologies, plasma immersion ion implantation (PIII) is a promising alternative to traditional beamline implantation. Currently, no commercial technology computer aided design (TCAD) process simulator allows modeling the complete USJ fabrication process by PIII, including as-implanted dopant profiles, damage formation, dopant diffusion and activation. In this work, a full simulation of a p-type BF{sub 3} PIII USJ has been carried out. In order to investigate the various physical phenomena mentioned above, process conditions included a high energy/high dose case (10 kV, 5 Multiplication-Sign 10{sup 15} cm{sup -2}), specifically designed to increase damage formation, as well as more technology relevant implant conditions (0.5 kV) for comparison. All implanted samples were annealed at different temperatures and times. As implanted profiles for both boron and fluorine in BF{sub 3} implants were modeled and compared to Secondary Ion Mass Spectrometry (SIMS) measurements. Amorphous/crystalline (a/c) interface depths were measured by transmission electron microscopy (TEM) and successfully simulated. Diffused profiles simulations agreed with SIMS data at low thermal budgets. A boron peak behind the a/c interface was observed in all annealed SIMS profiles for the 10 kV case, indicating boron trapping from EOR defects in this region even after high thermal budgets. TEM measurements on the annealed samples showed an end of range (EOR) defects survival behind the a/c interface, including large dislocation loops (DLs) lying on (001) plane parallel to the surface. In the last part of this work, activation simulations were compared to Hall measurements and confirmed the need to develop a (001) large BICs model.

  10. The Evolution of Breast Implants.

    PubMed

    Gabriel, Allen; Maxwell, G Patrick

    2015-10-01

    Breast augmentation remains one of the most common procedures performed in the United States. However, shape, feel, safety, and longevity of the implants remain important areas of research. The data provided by manufacturers show the safety and efficacy of these medical devices. Clinicians should strive to provide ongoing data and sound science to continue to improve clinical outcomes in the future. This article explores the evolution of breast implants with special emphasis on the advancement of silicone implants.

  11. Ectoine and hydroxyectoine as protectants against osmotic and cold stress: uptake through the SigB-controlled betaine-choline- carnitine transporter-type carrier EctT from Virgibacillus pantothenticus.

    PubMed

    Kuhlmann, Anne U; Hoffmann, Tamara; Bursy, Jan; Jebbar, Mohamed; Bremer, Erhard

    2011-09-01

    Virgibacillus pantothenticus has been shown to synthesize the compatible solute ectoine in response to high salinity or low growth temperature. We found that exogenously provided ectoine and hydroxyectoine also serve as protectants against these challenges. Transport studies with [(14)C]ectoine revealed that both types of stress induced a high-affinity ectoine uptake activity in V. pantothenticus. By using an Escherichia coli mutant defective in osmoprotectant uptake systems, a functional complementation approach for osmostress resistance in the presence of ectoine was employed to retrieve a gene encoding an ectoine transporter from V. pantothenticus. The cloned gene (ectT) encodes a protein (EctT) that is a member of the BCCT (betaine-choline-carnitine-transporter) family of carriers. Osmoprotection assays demonstrated that the EctT carrier mediates the preferential import of ectoine and hydroxyectoine but also possesses minor uptake activities for the compatible solutes proline and glycine betaine. Northern blot analysis with RNA isolated from V. pantothenticus revealed that a rise in the external osmolality or a reduction in growth temperature strongly increased the transcription of the ectT gene. Primer extension analysis demonstrated that ectT was transcribed under these conditions from a SigB-type promoter. SigB is the master regulator of the general stress regulon of bacilli and provides protection to cells against various challenges, including high salinity and low temperature. Both the synthesis of ectoine and the EctT-mediated uptake of ectoine and hydroxyectoine are triggered by the same environmental cues, high salinity and cold stress, and thereby provide, in a concerted fashion, the protection of V. pantothenticus against these challenges.

  12. Corynebacterium glutamicum is equipped with four secondary carriers for compatible solutes: identification, sequencing, and characterization of the proline/ectoine uptake system, ProP, and the ectoine/proline/glycine betaine carrier, EctP.

    PubMed

    Peter, H; Weil, B; Burkovski, A; Krämer, R; Morbach, S

    1998-11-01

    Gram-positive soil bacterium Corynebacterium glutamicum uses the compatible solutes glycine betaine, proline, and ectoine for protection against hyperosmotic shock. Osmoregulated glycine betaine carrier BetP and proline permease PutP have been previously characterized; we have identified and characterized two additional osmoregulated secondary transporters for compatible solutes in C. glutamicum, namely, the proline/ectoine carrier, ProP, and the ectoine/glycine betaine/proline carrier, EctP. A DeltabetP DeltaputP DeltaproP DeltaectP mutant was unable to respond to hyperosmotic stress, indicating that no additional uptake system for these compatible solutes is present. Osmoregulated ProP consists of 504 residues and preferred proline (Km, 48 microM) to ectoine (Km, 132 microM). The proP gene could not be expressed from its own promoter in C. glutamicum; however, expression was observed in Escherichia coli. ProP belongs to the major facilitator superfamily, whereas EctP, together with the betaine carrier, BetP, is a member of a newly established subfamily of the sodium/solute symporter superfamily. The constitutively expressed ectP codes for a 615-residue transporter. EctP preferred ectoine (Km, 63 microM) to betaine (Km, 333 microM) and proline (Km, 1,200 microM). Its activity was regulated by the external osmolality. The related betaine transporter, BetP, could be activated directly by altering the membrane state with local anesthetics, but this was not the case for EctP. Furthermore, the onset of osmotic activation was virtually instantaneous for BetP, whereas it took about 10 s for EctP.

  13. Ectoine and hydroxyectoine as protectants against osmotic and cold stress: uptake through the SigB-controlled betaine-choline- carnitine transporter-type carrier EctT from Virgibacillus pantothenticus.

    PubMed

    Kuhlmann, Anne U; Hoffmann, Tamara; Bursy, Jan; Jebbar, Mohamed; Bremer, Erhard

    2011-09-01

    Virgibacillus pantothenticus has been shown to synthesize the compatible solute ectoine in response to high salinity or low growth temperature. We found that exogenously provided ectoine and hydroxyectoine also serve as protectants against these challenges. Transport studies with [(14)C]ectoine revealed that both types of stress induced a high-affinity ectoine uptake activity in V. pantothenticus. By using an Escherichia coli mutant defective in osmoprotectant uptake systems, a functional complementation approach for osmostress resistance in the presence of ectoine was employed to retrieve a gene encoding an ectoine transporter from V. pantothenticus. The cloned gene (ectT) encodes a protein (EctT) that is a member of the BCCT (betaine-choline-carnitine-transporter) family of carriers. Osmoprotection assays demonstrated that the EctT carrier mediates the preferential import of ectoine and hydroxyectoine but also possesses minor uptake activities for the compatible solutes proline and glycine betaine. Northern blot analysis with RNA isolated from V. pantothenticus revealed that a rise in the external osmolality or a reduction in growth temperature strongly increased the transcription of the ectT gene. Primer extension analysis demonstrated that ectT was transcribed under these conditions from a SigB-type promoter. SigB is the master regulator of the general stress regulon of bacilli and provides protection to cells against various challenges, including high salinity and low temperature. Both the synthesis of ectoine and the EctT-mediated uptake of ectoine and hydroxyectoine are triggered by the same environmental cues, high salinity and cold stress, and thereby provide, in a concerted fashion, the protection of V. pantothenticus against these challenges. PMID:21764932

  14. Tissue response to the components of a hydroxyapatite-coated composite femoral implant.

    PubMed

    Hacking, S A; Pauyo, T; Lim, L; Legoux, J G; Bureau, M N

    2010-09-01

    Bone loss around femoral implants used for THA is a persistent clinical concern. It may be caused by stress shielding, generally attributed to a mismatch in stiffness between the implants and host bone. In this regard, a fatigue resistant, carbon fiber (CF) composite femoral implant with bone-matching stiffness has been developed. This study evaluated the tissue response to the three material components of this implant in normal and textured (blasted with 24 grit alumina) surfaces: the hydroxyapatite (HA) coating, the CF composite and the intermediate crystalline HA particulate composite layer to bond to the HA coating (blended). Sprague-Dawley rats underwent bilateral femoral implantation each receiving two rod-like implants. Bone apposition to the HA (37%) and textured Ti (41%) implants was not significantly different. Bone apposition to the untextured CF (14%) and blended (19%) implants and polished Ti (8%) implants was significantly lower. Bone apposition to the textured CF (9%) and blended (11%) implants was lower (but not statistically from the as received or untextured counterparts). Nearly all sections from femurs containing CF implants presented CF debris. There was no evidence of localized bone loss or any strong immune response associated with any of the implant materials. All materials were well tolerated with minimal inflammation despite the presence of particulate debris. The high degree of bone apposition to the HA-coated composite implants and the lack of short-term inflammation and adverse tissue response to the three material implant component support continued evaluation of this composite technology for use in THA. PMID:20730932

  15. Implant biomaterials: A comprehensive review

    PubMed Central

    Saini, Monika; Singh, Yashpal; Arora, Pooja; Arora, Vipin; Jain, Krati

    2015-01-01

    Appropriate selection of the implant biomaterial is a key factor for long term success of implants. The biologic environment does not accept completely any material so to optimize biologic performance, implants should be selected to reduce the negative biologic response while maintaining adequate function. Every clinician should always gain a thorough knowledge about the different biomaterials used for the dental implants. This article makes an effort to summarize various dental bio-materials which were used in the past and as well as the latest material used now. PMID:25610850

  16. Professional occupation after cochlear implantation.

    PubMed

    Kos, M-I; Degive, C; Boex, C; Guyot, J-P

    2007-03-01

    The aims of this study were to verify whether cochlear implants helped profoundly deaf adults to maintain or even to develop their professional occupations, and to identify other elements that may contribute to or, on the contrary, impede such patients' professional success. All adult patients received a questionnaire concerning their professional activities before and after implantation. Demographic data, health information, hearing performance and degree of satisfaction with the implant were also considered. Sixty-seven adults had been implanted, with three different devices, since 1985. At the time of implantation, 34 had been professionally active. After implantation, 29 had remained professionally active, four of whom reported positive developments in their careers. Five patients had become professionally inactive. Those patients who had previously been professionally inactive remained so. There had been no difference in performance, either between different types of cochlear implants or between professionally active or inactive patients. The implanted patients had kept their jobs and many of them had developed their professional skills. In spite of this, cochlear implants may still be perceived as proving insufficiently satisfactory hearing to enable professionally inactive patients to reintegrate and to facilitate further learning or career developments. PMID:17052367

  17. The socially constructed breast: breast implants and the medical construction of need.

    PubMed Central

    Jacobson, N

    1998-01-01

    When silicone gel breast implants became the subject of a public health controversy in the early 1990s, the most pressing concern was safety. This paper looks at another, less publicized issue: the need for implants. Using a symbolic interactionist approach, the author explores the social construction of the need for implants by tracing the history of the 3 surgical procedures for which implants were used. Stakeholders in this history constructed need as legitimized individual desire, the form of which shifted with changes in the technological and social context. PMID:9702166

  18. Implantable medical sensor system

    DOEpatents

    Darrow, Christopher B.; Satcher, Jr., Joe H.; Lane, Stephen M.; Lee, Abraham P.; Wang, Amy W.

    2001-01-01

    An implantable chemical sensor system for medical applications is described which permits selective recognition of an analyte using an expandable biocompatible sensor, such as a polymer, that undergoes a dimensional change in the presence of the analyte. The expandable polymer is incorporated into an electronic circuit component that changes its properties (e.g., frequency) when the polymer changes dimension. As the circuit changes its characteristics, an external interrogator transmits a signal transdermally to the transducer, and the concentration of the analyte is determined from the measured changes in the circuit. This invention may be used for minimally invasive monitoring of blood glucose levels in diabetic patients.

  19. Broad beam ion implanter

    DOEpatents

    Leung, K.N.

    1996-10-08

    An ion implantation device for creating a large diameter, homogeneous, ion beam is described, as well as a method for creating same, wherein the device is characterized by extraction of a diverging ion beam and its conversion by ion beam optics to an essentially parallel ion beam. The device comprises a plasma or ion source, an anode and exit aperture, an extraction electrode, a divergence-limiting electrode and an acceleration electrode, as well as the means for connecting a voltage supply to the electrodes. 6 figs.

  20. Broad beam ion implanter

    DOEpatents

    Leung, Ka-Ngo

    1996-01-01

    An ion implantation device for creating a large diameter, homogeneous, ion beam is described, as well as a method for creating same, wherein the device is characterized by extraction of a diverging ion beam and its conversion by ion beam optics to an essentially parallel ion beam. The device comprises a plasma or ion source, an anode and exit aperture, an extraction electrode, a divergence-limiting electrode and an acceleration electrode, as well as the means for connecting a voltage supply to the electrodes.

  1. Bone cement implantation syndrome.

    PubMed

    Razuin, R; Effat, O; Shahidan, M N; Shama, D V; Miswan, M F M

    2013-06-01

    Bone cement implantation syndrome (BCIS) is characterized by hypoxia, hypotension, cardiac arrhythmias, increased pulmonary vascular resistance and cardiac arrest. It is a known cause of morbidity and mortality in patients undergoing cemented orthopaedic surgeries. The rarity of the condition as well as absence of a proper definition has contributed to under-reporting of cases. We report a 59-year-old woman who sustained fracture of the neck of her left femur and underwent an elective hybrid total hip replacement surgery. She collapsed during surgery and was revived only to succumb to death twelve hours later. Post mortem findings showed multiorgan disseminated microembolization of bone marrow and amorphous cement material. PMID:23817399

  2. Resonance ultrasonic vibrations in Cz-Si wafers as a possible diagnostic technique in ion implantation

    NASA Astrophysics Data System (ADS)

    Zhao, Z. Y.; Ostapenko, S.; Anundson, R.; Tvinnereim, M.; Belyaev, A.; Anthony, M.

    2001-07-01

    The semiconductor industry does not have effective metrology for well implants. The ability to measure such deep level implants will become increasingly important as we progress along the technology road map. This work explores the possibility of using the acoustic whistle effect on ion implanted silicon wafers. The technique detects the elastic stress and defects in silicon wafers by measuring the sub-harmonic f/2 resonant vibrations on a wafer induced via backside contact to create standing waves, which are measured by a non-contact ultrasonic probe. Preliminary data demonstrates that it is sensitive to implant damage, and there is a direct correlation between this sub-harmonic acoustic mode and some of the implant and anneal conditions. This work presents the results of a feasibility study to assess and quantify the correspondent whistle effect to implant damage, residual damage after annealing and intrinsic defects.

  3. MED-EL Cochlear Implants: State of the Art and a Glimpse Into the Future

    PubMed Central

    Hochmair, Ingeborg; Nopp, Peter; Jolly, Claude; Schmidt, Marcus; Schößer, Hansjörg; Garnham, Carolyn; Anderson, Ilona

    2006-01-01

    Cochlear implantation is an accepted treatment method for adults and children with severe to profound hearing loss. Confidence in technology has led to changes in individuals who can receive a cochlear implant and changes in expected benefit with a cochlear implant. This article describes the research and development activities at MED-EL, which make possible the implementation of new speech-coding strategies as well as the application of acoustic and electric stimulation via a combined speech processor in MED-EL devices. Research on benefits from bilateral cochlear implantation and electric-acoustic stimulation are also reviewed. Finally, the potential of drug delivery systems is considered as a way to improve cochlear implant outcomes, and results from preliminary evaluations of a hybrid cochlear implant system with drug delivery capabilities are reported. PMID:17172548

  4. The Educational Technology Centre: A Window to View the Progress of Chinese ICT-Based Higher Education

    ERIC Educational Resources Information Center

    Zhou, Rong; Xie, Baizhi

    2010-01-01

    In China, after many years, the current status and challenges of e-learning development in higher education have been gradually understood. The educational technology centre (ECT) serves as the key unit to promote e-learning initiatives, but the performance of some centres still trails their foreign counterparts. Under such conditions, the project…

  5. Developing Mentoring Relationships to Support the Careers of Women in Electrical Engineering and Computer Technologies. An Analysis on Mentors' Competencies

    ERIC Educational Resources Information Center

    Pisimisi, S. S.; Ioannides, M. G.

    2005-01-01

    Only a low percent of women follow studies and develop careers in the field of engineering and computer technologies (E/CT). An initiative for motivating and supporting young women towards future educational paths and careers in this field was undertaken in the framework of a European thematic network with the involvement of universities from…

  6. Accuracy of computer-aided template-guided oral implant placement: a prospective clinical study

    PubMed Central

    2014-01-01

    Purpose The aim of the present study was to evaluate the in vivo accuracy of flapless, computer-aided implant placement by comparing the three-dimensional (3D) position of planned and placed implants through an analysis of linear and angular deviations. Methods Implant position was virtually planned using 3D planning software based on the functional and aesthetic requirements of the final restorations. Computer-aided design/computer-assisted manufacture technology was used to transfer the virtual plan to the surgical environment. The 3D position of the planned and placed implants, in terms of the linear deviations of the implant head and apex and the angular deviations of the implant axis, was compared by overlapping the pre- and postoperative computed tomography scans using dedicated software. Results The comparison of 14 implants showed a mean linear deviation of the implant head of 0.56 mm (standard deviation [SD], 0.23), a mean linear deviation of the implant apex of 0.64 mm (SD, 0.29), and a mean angular deviation of the long axis of 2.42° (SD, 1.02). Conclusions In the present study, computer-aided flapless implant surgery seemed to provide several advantages to the clinicians as compared to the standard procedure; however, linear and angular deviations are to be expected. Therefore, accurate presurgical planning taking into account anatomical limitations and prosthetic demands is mandatory to ensure a predictable treatment, without incurring possible intra- and postoperative complications. Graphical Abstract PMID:25177520

  7. The implant neck: smooth or provided with retention elements. A biomechanical approach.

    PubMed

    Hansson, S

    1999-10-01

    A combined three-dimensional and axisymmetric finite element analysis was made of the effect upon the peak interfacial shear stress of providing an axially loaded mandibular dental implant with retention elements all the way up to the crest of the implant as opposed to a smooth neck. The effect of increased wall thickness of the implant and of using bi-cortical fixation as opposed to uni-cortical fixation was also studied. Retention elements at the implant neck were found to bring about a major decrease in the peak interfacial shear stress. Increased wall thickness and bi-cortical fixation also resulted in decreased peak interfacial shear stress but this effect was minor. The interpretation of this was that all these three measures increase the capacity of the implant to carry axial loads. Thus from a biomechanical viewpoint it appears to be advantageous to provide the neck of screw-shaped implants with retention elements, for example a rough surface of suitable micro-architecture and/or a micro-thread. It is furthermore suggested that retention elements at the implant neck will counteract marginal bone resorption in accordance with Wolff's law. This paper is a revision of: Hansson, S. (1997) Some steps to improve the capacity of dental implants to resist axial loads. In: Hansson, S., ed. Towards an optimized dental implant and implant bridge design: A biomechanical approach. Thesis. Göteborg: Chalmers University of Technology.

  8. A remotely powered implantable biomedical system with location detector.

    PubMed

    Kilinc, Enver G; Ghanad, Mehrdad A; Maloberti, Franco; Dehollain, Catherine

    2015-02-01

    An universal remote powering and communication system is presented for the implantable medical devices. The system be interfaced with different sensors or actuators. A mobile external unit controls the operation of the implantable chip and reads the sensor's data. A locator system is proposed to align the mobile unit with the implant unit for the efficient magnetic power transfer. The location of the implant is detected with 6 mm resolution from the rectified voltage level at the implanted side. The rectified voltage level is fedback to the mobile unit to adjust the magnetic field strength and maximize the efficiency of the remote powering system. The sensor's data are transmitted by using a free running oscillator modulated with on-off key scheme. To tolerate large data carrier drifts, a custom designed receiver is implemented for the mobile unit. The circuits have been fabricated in 0.18 um CMOS technology. The remote powering link is optimized to deliver power at 13.56 MHz. On chip voltage regulator creates 1.8 V from a 0.9 V reference voltage to supply the sensor/actuator blocks. The implantable chip dissipates 595 μW and requires 1.48 V for start up. PMID:24988596

  9. Development of Implantable Medical Devices: From an Engineering Perspective

    PubMed Central

    2013-01-01

    From the first pacemaker implant in 1958, numerous engineering and medical activities for implantable medical device development have faced challenges in materials, battery power, functionality, electrical power consumption, size shrinkage, system delivery, and wireless communication. With explosive advances in scientific and engineering technology, many implantable medical devices such as the pacemaker, cochlear implant, and real-time blood pressure sensors have been developed and improved. This trend of progress in medical devices will continue because of the coming super-aged society, which will result in more consumers for the devices. The inner body is a special space filled with electrical, chemical, mechanical, and marine-salted reactions. Therefore, electrical connectivity and communication, corrosion, robustness, and hermeticity are key factors to be considered during the development stage. The main participants in the development stage are the user, the medical staff, and the engineer or technician. Thus, there are three different viewpoints in the development of implantable devices. In this review paper, considerations in the development of implantable medical devices will be presented from the viewpoint of an engineering mind. PMID:24143287

  10. Therapies targeting inflammation after stent implantation.

    PubMed

    Okura, Hiroyuki; Takagi, Tsutomu; Yoshida, Kiyoshi

    2013-07-01

    Since the introduction of coronary vessel scaffold by metallic stent, percutaneous coronary intervention has become widely performed all over the world. Although drug-eluting stent technology has further decrease the incidence of in-stent restenosis, there still remaining issues related to stent implantation. Vessel inflammation is one of the causes that may be related to stent restenosis as well as stent thrombosis. Therefore, systemic therapies targeting inflammation emerged as adjunctive pharmacological intervention to improve outcome. Statins, corticosteroids, antiplatelets, and immunosuppresive or anti-cancer drugs are reported to favorably impact outcome after bare-metal stent implantation. In type 2 diabetic patients, pioglitazone may be the most promising drug that can lower neointimal proliferation and, as a result, lower incidence of restenosis and target lesion revascularization. On the other hand, several new stent platforms that might decrease inflammatory response after drug-eluting stent implantation have been introduced. Because durable polymer used in the first generation drug-eluting stents are recognized to be responsible for unfavorable vessel response, biocompatible or bioabsorbable polymer has been introduce and already used clinically. Furthermore, polymer-free drug-eluting stent and bioresorbable scaffold are under investigation. Although vessel inflammation may be reduced by using these new drug-eluting stents or scaffold, long-term impact needs to be investigated further. PMID:23905635

  11. The Implantable Cardiac Pacemaker

    PubMed Central

    Trimble, A. S.; Heimbecker, R. O.; Bigelow, W. G.

    1964-01-01

    The transistorized implanted pacemaker is proving to be an effective and reliable method for long-term pacing of the heart. All patients suffering from Stokes-Adams seizures were first given a trial period of conservative therapy, including isoproterenol (Isuprel), ephedrine, atropine and steroids. Twenty-four pacemaker implants were performed on 23 patients over a 21-month period. The preoperative insertion of a pacemaker cardiac catheter was a very valuable safety precaution. In this way the heart could be safely and reliably paced during the period of preoperative assessment and during the critical periods of anesthetic induction and thoracotomy. Infection did not occur, probably because of careful gas sterilization of the units. Various models of pacemakers are compared, and the reasons for two pacemaker failures are presented. There were two early deaths and one late death in the series. The relationship of progressive coronary disease to recent infarction is stressed. Patients having intermittent heart block frequently showed the picture of “competing pacemakers” postoperatively, but without deleterious effect. Twenty patients, between 54 and 88 years of age, are alive and well at the time of reporting, with excellent pacemaker response and no further Stokes-Adams attacks. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6 PMID:14118681

  12. Transcatheter aortic valve implantation.

    PubMed

    Kapadia, Samir R; Tuzcu, E Murat

    2009-12-01

    Aortic stenosis is the most important valvular heart disease affecting the elderly population. Surgical aortic valve replacement is the mainstay of treatment, although a substantial number of patients are considered high risk for surgery. Many of these patients do not undergo surgery and have poor outcomes from medically treated symptomatic, severe aortic stenosis. Transcatheter aortic valve implantation (TAVI) provides a promising treatment option for some of these patients. Several devices are under investigation. The Edwards Sapien valve (Edwards Lifesciences, Irvine, CA) and the CoreValve (Medtronic, Minneapolis, MN) have the largest human experience to date. Initial data suggest that these devices have an acceptable safety profile and provide excellent hemodynamic relief of aortic stenosis. The Edwards Sapien valve is currently under investigation in the United States in the PARTNER (Placement of Aortic Transcatheter Valve) trial in high-risk surgical or inoperable patients; TAVI is available for clinical use in both Canada and Europe. TAVI is not used in low- or intermediate-risk surgical patients; however, future studies may prove its applicability in these subsets. The major complications of TAVI include access site-related problems and device malpositioning/migration. There are several new-generation prosthetic valves and delivery systems designed to be low profile and repositionable. Technical advances and refinement of the implantation methods may make TAVI even safer and ultimately a better treatment option, not only for patients with high surgical risk but also for those with moderate or low risk.

  13. Porous metal for orthopedics implants

    PubMed Central

    Matassi, Fabrizio; Botti, Alessandra; Sirleo, Luigi; Carulli, Christian; Innocenti, Massimo

    2013-01-01

    Summary Porous metal has been introduced to obtain biological fixation and improve longevity of orthopedic implants. The new generation of porous metal has intriguing characteristics that allows bone healing and high osteointegration of the metallic implants. This article gives an overview about biomaterials properties of the contemporary class of highly porous metals and about the clinical use in orthopaedic surgery. PMID:24133527

  14. Implant Maintenance: A Clinical Update

    PubMed Central

    Gulati, Minkle; Govila, Vivek; Anand, Vishal; Anand, Bhargavi

    2014-01-01

    Introduction. The differences in the supporting structure of the implant make them more susceptible to inflammation and bone loss when plaque accumulates as compared to the teeth. Therefore, a comprehensive maintenance protocol should be followed to ensure the longevity of the implant. Material and Method. A research to provide scientific evidence supporting the feasibility of various implant care methods was carried out using various online resources to retrieve relevant studies published since 1985. Results. The electronic search yielded 708 titles, out of which a total of 42 articles were considered appropriate and finally included for the preparation of this review article. Discussion. A typical maintenance visit for patients with dental implants should last 1 hour and should be scheduled every 3 months to evaluate any changes in their oral and general history. It is essential to have a proper instrument selection to prevent damage to the implant surface and trauma to the peri-implant tissues. Conclusion. As the number of patients opting for dental implants is increasing, it becomes increasingly essential to know the differences between natural teeth and implant care and accept the challenges of maintaining these restorations. PMID:27437506

  15. Awake transapical aortic valve implantation.

    PubMed

    Petridis, Francesco Dimitri; Savini, Carlo; Castelli, Andrea; Di Bartolomeo, Roberto

    2012-05-01

    Transapical aortic valve implantation is being employed as a less invasive alternative to open heart surgery in high-risk patients with severe aortic stenosis. Here we report the case of an awake transapical aortic valve implantation in a patient with severe chronic obstructive pulmonary disease.

  16. Regenerative Surgical Treatment of Peri-implantitis

    ClinicalTrials.gov

    2016-08-31

    Failure of Dental Implant Due to Infection; Infection; Inflammation; Peri-implantitis; Bacterial Infections; Bleeding of Subgingival Space; Molecular Sequence Variation; Periodontal Diseases; Mouth Diseases

  17. Bioceramic in dental implants: A review.

    PubMed

    Jayaswal, Gaurav P; Dange, S P; Khalikar, A N

    2010-03-01

    Biomaterials are non-drug substance suitable for inclusion in system which augment or replace the function of bodily tissue or organ. Orthopedic and dental applications represent approximately 55% of the total biomaterials market. Changes in biologic responses and device design have been the direct result of advances in material science. Bioceramics fulfill a unique function as biomedical materials. Bioceramics are non-toxic and bioinert, bioactive or bioresorbable. Bioceramics continue to be vital for bone repair and uncemented implant fixation with recent advances in its composition and coating technology.

  18. Additive manufacturing: From implants to organs.

    PubMed

    Douglas, Tania S

    2014-06-01

    Additive manufacturing (AM) constructs 3D objects layer by layer under computer control from 3D models. 3D printing is one example of this kind of technology. AM offers geometric flexibility in its products and therefore allows customisation to suit individual needs. Clinical success has been shown with models for surgical planning, implants, assistive devices and scaffold-based tissue engineering. The use of AM to print tissues and organs that mimic nature in structure and function remains an elusive goal, but has the potential to transform personalised medicine, drug development and scientific understanding of the mechanisms of disease.  PMID:25214247

  19. Additive manufacturing: From implants to organs.

    PubMed

    Douglas, Tania S

    2014-05-12

    Additive manufacturing (AM) constructs 3D objects layer by layer under computer control from 3D models. 3D printing is one example of this kind of technology. AM offers geometric flexibility in its products and therefore allows customisation to suit individual needs. Clinical success has been shown with models for surgical planning, implants, assistive devices and scaffold-based tissue engineering. The use of AM to print tissues and organs that mimic nature in structure and function remains an elusive goal, but has the potential to transform personalised medicine, drug development and scientific understanding of the mechanisms of disease. 

  20. Transcatheter aortic valve implantation: past, present and future.

    PubMed

    Keshavarzi, Freidoon; MacCarthy, Philip

    2016-03-01

    Transcatheter aortic valve implantation is one of the most significant technological advances in cardiovascular medicine. It offers a safe alternative in high risk cardiac patients with proven durability, economical viability and survival advantage. Current trials may expand its application in intermediate or low risk groups. PMID:26961440

  1. Production of Endohedral Fullerenes by Ion Implantation

    SciTech Connect

    Diener, M.D.; Alford, J. M.; Mirzadeh, S.

    2007-05-31

    The empty interior cavity of fullerenes has long been touted for containment of radionuclides during in vivo transport, during radioimmunotherapy (RIT) and radioimaging for example. As the chemistry required to open a hole in fullerene is complex and exceedingly unlikely to occur in vivo, and conformational stability of the fullerene cage is absolute, atoms trapped within fullerenes can only be released during extremely energetic events. Encapsulating radionuclides in fullerenes could therefore potentially eliminate undesired toxicity resulting from leakage and catabolism of radionuclides administered with other techniques. At the start of this project however, methods for production of transition metal and p-electron metal endohedral fullerenes were completely unknown, and only one method for production of endohedral radiofullerenes was known. They therefore investigated three different methods for the production of therapeutically useful endohedral metallofullerenes: (1) implantation of ions using the high intensity ion beam at the Oak Ridge National Laboratory (ORNL) Surface Modification and Characterization Research Center (SMAC) and fullerenes as the target; (2) implantation of ions using the recoil energy following alpha decay; and (3) implantation of ions using the recoil energy following neutron capture, using ORNL's High Flux Isotope Reactor (HFIR) as a thermal neutron source. While they were unable to obtain evidence of successful implantation using the ion beam at SMAC, recoil following alpha decay and neutron capture were both found to be economically viable methods for the production of therapeutically useful radiofullerenes. In this report, the procedures for preparing fullerenes containing the isotopes {sup 212}Pb, {sup 212}Bi, {sup 213}Bi, and {sup 177}Lu are described. None of these endohedral fullerenes had ever previously been prepared, and all of these radioisotopes are actively under investigation for RIT. Additionally, the chemistry for

  2. [Dental implants in tooth grinders].

    PubMed

    Lobbezoo, F; Brouwers, J E; Cune, M S; Naeije, M

    2004-03-01

    Bruxism (tooth grinding and clenching) is generally considered a contraindication for dental implants, although the evidence is usually based on clinical experience only. So far, studies to the possible cause-and-effect relationship between bruxism and implant failure do not yield consistent and specific outcomes. This is partly due to the large variation in the technical and the biological aspects of the investigations. Although there is still no proof that bruxism causes overload of dental implants and their suprastructures, a careful approach is recommended. Practical advices as to minimize the chance of implant failure are given. Besides the recommendation to reduce or eliminate bruxism itself, these advices concern the number and dimensions of the implants, the design of the occlusion and articulation patterns, and the use of a hard nightguard. PMID:15058243

  3. Speech Production Intelligibility of Early Implanted Pediatric Cochlear Implant Users

    PubMed Central

    Habib, Mirette G.; Waltzman, Susan B.; Tajudeen, Bobby; Svirsky, Mario A.

    2010-01-01

    Objectives To investigate the influence of age, and age at implantation, on speech production intelligibility in prelingually deaf pediatric cochlear implant recipients. Methods Forty prelingually, profoundly deaf children who received cochlear implants between 8 and 40 months of age. Their age at testing ranged between 2.5 – 18 years. Children were recorded repeating the ten sentences in the Beginner’s Intelligibility Test. These recordings were played back to normal-hearing listeners who were unfamiliar with deaf speech and who were instructed to write down what they heard. They also rated each subject for the intelligibility of their speech production on a 5-point rating scale. The main outcome measures were the percentage of target words correctly transcribed, and the intelligibility ratings, in both cases averaged across three normal-hearing listeners. Results The data showed a strong effect of age at testing, with older children being more intelligible. This effect was particularly pronounced for children implanted in the first 24 months of life, all of whom had speech production intelligibility scores of 80% or higher when they were tested at age 5.5 years or older. This was true for only five out of nine children implanted at age 25 to 36 months. Conclusions Profoundly deaf children who receive cochlear implants in the first two years of life produce highly intelligible speech before age 6. This is also true for most, but not all children implanted in their third year. PMID:20472308

  4. Engineering of implantable liver tissues.

    PubMed

    Sakai, Yasuyuki; Nishikawa, M; Evenou, F; Hamon, M; Huang, H; Montagne, K P; Kojima, N; Fujii, T; Niino, T

    2012-01-01

    In this chapter, from the engineering point of view, we introduce the results from our group and related research on three typical configurations of engineered liver tissues; cell sheet-based tissues, sheet-like macroporous scaffold-based tissues, and tissues based on special scaffolds that comprise a flow channel network. The former two do not necessitate in vitro prevascularization and are thus promising in actual human clinical trials for liver diseases that can be recovered by relatively smaller tissue mass. The third approach can implant a much larger mass but is still not yet feasible. In all cases, oxygen supply is the key engineering factor. For the first configuration, direct oxygen supply using an oxygen-permeable polydimethylsiloxane membrane enables various liver cells to exhibit distinct behaviors, complete double layers of mature hepatocytes and fibroblasts, spontaneous thick tissue formation of hepatocarcinoma cells and fetal hepatocytes. Actual oxygen concentration at the cell level can be strictly controlled in this culture system. Using this property, we found that initially low then subsequently high oxygen concentrations were favorable to growth and maturation of fetal cells. For the second configuration, combination of poly-L: -lactic acid 3D scaffolds and appropriate growth factor cocktails provides a suitable microenvironment for the maturation of cells in vitro but the cell growth is limited to a certain distance from the inner surfaces of the macropores. However, implantation to the mesentery leaves of animals allows the cells again to proliferate and pack the remaining spaces of the macroporous structure, suggesting the high feasibility of 3D culture of hepatocyte progenitors for liver tissue-based therapies. For the third configuration, we proposed a design criterion concerning the dimensions of flow channels based on oxygen diffusion and consumption around the channel. Due to the current limitation in the resolution of 3D

  5. Transcatheter aortic valve implantation.

    PubMed

    Nielsen, Hans Henrik Møller

    2012-12-01

    Transcatheter aortic valve implantation (TAVI) was introduced experimentally in 1989, based on a newly developed heart valve prosthesis - the stentvalve. The valve was invented by a Danish cardiologist named Henning Rud Andersen. The new valve was revolutionary. It was foldable and could be inserted via a catheter through an artery in the groin, without the need for heart lung machine. This allowed for a new valve implantation technique, much less invasive than conventional surgical aortic valve replacement (SAVR). Surgical aortic valve replacement is safe and improves symptoms along with survival. However, up to 1/3 of patients with aortic valve stenosis cannot complete the procedure due to frailty. The catheter technique was hoped to provide a new treatment option for these patients. The first human case was in 2002, but more widespread clinical use did not begin until 2006-2010. Today, in 2011, more than 40,000 valves have been implanted worldwide. Initially, because of the experimental character of the procedure, TAVI was reserved for patients who could not undergo SAVR due to high risk. The results in this group of patients were promising. The procedural safety was acceptable, and the patients experienced significant improvements in their symptoms. Three of the papers in this PhD-thesis are based on the outcome of TAVI at Skejby Hospital, in this high-risk population [I, II and IV]. Along with other international publications, they support TAVI as being superior to standard medical treatment, despite a high risk of prosthetic regurgitation. These results only apply to high-risk patients, who cannot undergo SAVR. The main purpose of this PhD study has been to investigate the quality of TAVI compared to SAVR, in order to define the indications for this new procedure. The article attached [V] describes a prospective clinical randomised controlled trial, between TAVI to SAVR in surgically amenable patients over 75 years of age with isolated aortic valve stenosis

  6. Percutaneous Pulmonary Valve Implantation

    PubMed Central

    Lee, Hyoung-Doo

    2012-01-01

    Pulmonary regurgitation (PR) is a frequent sequelae after repair of tetralogy of Fallot, pulmonary atresia, truncus arteriosus, Rastelli and Ross operation. Due to patient growth and conduit degeneration, these conduits have to be changed frequently due to regurgitation or stenosis. However, morbidity is significant in these repeated operations. To prolong conduit longevity, bare-metal stenting in the right ventricular outflow tract (RVOT) obstruction has been performed. Stenting the RVOT can reduce the right ventricular pressure and symptomatic improvement, but it causes PR with detrimental effects on the right ventricle function and risks of arrhythmia. Percutaneous pulmonary valve implantation has been shown to be a safe and effective treatment for patients with pulmonary valve insufficiency, or stenotic RVOTs. PMID:23170091

  7. Implantable optical-electrode device for stimulation of spinal motoneurons

    NASA Astrophysics Data System (ADS)

    Matveev, M. V.; Erofeev, A. I.; Zakharova, O. A.; Pyatyshev, E. N.; Kazakin, A. N.; Vlasova, O. L.

    2016-08-01

    Recent years, optogenetic method of scientific research has proved its effectiveness in the nerve cell stimulation tasks. In our article we demonstrate an implanted device for the spinal optogenetic motoneurons activation. This work is carried out in the Laboratory of Molecular Neurodegeneration of the Peter the Great St. Petersburg Polytechnic University, together with Nano and Microsystem Technology Laboratory. The work of the developed device is based on the principle of combining fiber optic light stimulation of genetically modified cells with the microelectrode multichannel recording of neurons biopotentials. The paper presents a part of the electrode implant manufacturing technique, combined with the optical waveguide of ThorLabs (USA).

  8. Implantation of Vascular Grafts Lined with Genetically Modified Endothelial Cells

    NASA Astrophysics Data System (ADS)

    Wilson, James M.; Birinyi, Louis K.; Salomon, Robert N.; Libby, Peter; Callow, Allan D.; Mulligan, Richard C.

    1989-06-01

    The possibility of using the vascular endothelial cell as a target for gene replacement therapy was explored. Recombinant retroviruses were used to transduce the lacZ gene into endothelial cells harvested from mongrel dogs. Prosthetic vascular grafts seeded with the genetically modified cells were implanted as carotid interposition grafts into the dogs from which the original cells were harvested. Analysis of the graft 5 weeks after implantation revealed genetically modified endothelial cells lining the luminal surface of the graft. This technology could be used in the treatment of atherosclerosis disease and the design of new drug delivery systems.

  9. Vascular Tissue Engineering: Building Perfusable Vasculature for Implantation

    PubMed Central

    Gui, Liqiong; Niklason, Laura E.

    2014-01-01

    Tissue and organ replacement is required when there are no alternative therapies available. Although vascular tissue engineering was originally developed to meet the clinical demands of small-diameter vascular conduits as bypass grafts, it has evolved into a highly advanced field where perfusable vasculatures are generated for implantation. Herein, we review several cutting-edge techniques that have led to implantable human blood vessels in clinical trials, the novel approaches that build complex perfusable microvascular networks in functional tissues, the use of stem cells to generate endothelial cells for vascularization, as well as the challenges in bringing vascular tissue engineering technologies into the clinics. PMID:24533306

  10. MEMS fabricated chip for an implantable drug delivery device.

    PubMed

    Sbiaa, Z

    2006-01-01

    We present a silicon-based implantable drug delivery system (IDDS) for the administration of compounds in vivo. The implanted device contains the drug-filled silicon microchip, control circuitry, telemetry capability, and a battery. At the heart of the IDDS is the drug-containing microchip, a MEMS (MicroElectroMechanical Systems)-based device. A process was developed for the fabrication of the silicon chip. MicroCHIPS' drug release technology has been successfully demonstrated in vitro and in vivo using the therapeutic peptide leuprolide as a model compound.

  11. Hardness of ion implanted ceramics

    SciTech Connect

    Oliver, W.C.; McHargue, C.J.; Farlow, G.C.; White, C.W.

    1985-01-01

    It has been established that the wear behavior of ceramic materials can be modified through ion implantation. Studies have been done to characterize the effect of implantation on the structure and composition of ceramic surfaces. To understand how these changes affect the wear properties of the ceramic, other mechanical properties must be measured. To accomplish this, a commercially available ultra low load hardness tester has been used to characterize Al/sub 2/O/sub 3/ with different implanted species and doses. The hardness of the base material is compared with the highly damaged crystalline state as well as the amorphous material.

  12. [Future of implantable electrical cardiac devices].

    PubMed

    Daubert, Jean-Claude; Behaghel, Albin; Leclercq, Christophe; Mabo, Philippe

    2014-03-01

    Major improvements in implantable electrical cardiac devices have been made during the last two decades, notably with the advent of automatic internal defibrillation (ICD) to prevent sudden arrhythmic death, and cardiac resynchronisation (CRT) to treat the discoordinated failing heart. They now constitute a major therapeutic option and may eventually supersede drug therapy. The coming era will be marked by a technological revolution, with improvements in treatment delivery, safety and efficacy, and an expansion of clinical indications. Leadless technologyfor cardiac pacemakers and defibrillators is already in the pipeline, endovascular leads currently being responsible for most long-term complications (lead failure, infection, vein thrombosis, etc.). Miniaturized pacemakers based on nanotechnology can now be totally implanted inside the right ventricle through the transvenous route, thus eliminating leads, pockets and scarring In the same way, totally subcutaneous ICD systems are now available, although they are currently only capable of delivering shocks, without pacing (including antitachycardia pacing). In CRT optimised delivery is important to improve clinical responses and to reduce the non-response rate (around 30 % with current technology). Endocardial left ventricular pacing could be a solution if it can be achieved at an acceptable risk. Multisite ventricular pacing is an alternative. Besides CRT neuromodulation, especially by vagal stimulation, is another important field of device researchfor heart failure. Preliminary clinical results are encouraging. PMID:26427291

  13. Investigation of the silicone structure in breast implants using ¹H NMR.

    PubMed

    Formes, Andreas; Diehl, Bernd

    2014-05-01

    Against the background of the scandal about low-grade silicone breast implants of the French manufacturer Poly Implant Prothese (PIP), several types of implants were examined using (1)H NMR spectroscopy. The intention was to classify an implant according to its silicone structure. Therefore, the certificated raw material of the American silicone producer Nusil Technology was analyzed and used as a reference. The list of tested implants consists of implants by PFM medical, PIP, Silimed, Rofil, Eurosilicone, Mentor, Perouse Plastie, Polytech, Nagor, CUI, and McGhan. In the (1)H NMR spectrum the signal of the vinyl group, which is used to cross link silicone rubbers, is visible. It is possible to differentiate between silicones which have a vinyl terminated end group and silicones whose vinyl group is located within the chain of the polymer. The two different types of the vinyl group are one mean to classify the implants. Other categories besides the type of vinyl include the relative amount of the remaining vinyl in the implant and the chemical structure of the material used for the production of the envelope. With these characteristics the examined implants could be grouped into four types. PMID:24342752

  14. Design and manufacturing of cranioplasty implants by 3-axis cnc milling.

    PubMed

    Hieu, L C; Bohez, E; Vander Sloten, J; Oris, P; Phien, H N; Vatcharaporn, E; Binh, P H

    2002-01-01

    Although various techniques and materials have been used for making cranioplasty implants, personalized cranioplasty implants are high in cost because of expensive materials and production technology, long design and manufacturing time, and intensive labor use. This research was a part of our research project in ASEAN countries to investigate feasible technical solutions of minimizing the implant cost based on available production technologies in the region. The use of 3-axis CNC (Computer Numerical Control) milling techniques for making molds to fabricate PMMA implants was successfully investigated. With the development of a design support program bridging between Computer Aided Design (CAD) and Medical Image Processing (MIP) system, the time for geometrical modeling of implants and molds was reduced to half a day. The machining time to complete a mold was about 5 to 6 hours; and it took maximal 2 hours to fabricate an implant with self-curing PMMA and 3 and half hours for fabricating an implant with heat-curing PMMA. The cost of implants is acceptable for the ASEAN region. PMID:12368561

  15. Implantable Cardioverter Defibrillators. Prophylactic Use

    PubMed Central

    2005-01-01

    Executive Summary Objective The use of implantable cardiac defibrillators (ICDs) to prevent sudden cardiac death (SCD) in patients resuscitated from cardiac arrest or documented dangerous ventricular arrhythmias (secondary prevention of SCD) is an insured service. In 2003 (before the establishment of the Ontario Health Technology Advisory Committee), the Medical Advisory Secretariat conducted a health technology policy assessment on the prophylactic use (primary prevention of SCD) of ICDs for patients at high risk of SCD. The Medical Advisory Secretariat concluded that ICDs are effective for the primary prevention of SCD. Moreover, it found that a more clearly defined target population at risk for SCD that would be likely to benefit from ICDs is needed, given that the number needed to treat (NNT) from recent studies is 13 to 18, and given that the per-unit cost of ICDs is $32,000, which means that the projected cost to Ontario is $770 million (Cdn). Accordingly, as part of an annual review and publication of more recent articles, the Medical Advisory Secretariat updated its health technology policy assessment of ICDs. Clinical Need Sudden cardiac death is caused by the sudden onset of fatal arrhythmias, or abnormal heart rhythms: ventricular tachycardia (VT), a rhythm abnormality in which the ventricles cause the heart to beat too fast, and ventricular fibrillation (VF), an abnormal, rapid and erratic heart rhythm. About 80% of fatal arrhythmias are associated with ischemic heart disease, which is caused by insufficient blood flow to the heart. Management of VT and VF with antiarrhythmic drugs is not very effective; for this reason, nonpharmacological treatments have been explored. One such treatment is the ICD. The Technology An ICD is a battery-powered device that, once implanted, monitors heart rhythm and can deliver an electric shock to restore normal rhythm when potentially fatal arrhythmias are detected. The use of ICDs to prevent SCD in patients resuscitated

  16. Wireless microsensor network solutions for neurological implantable devices

    NASA Astrophysics Data System (ADS)

    Abraham, Jose K.; Whitchurch, Ashwin; Varadan, Vijay K.

    2005-05-01

    The design and development of wireless mocrosensor network systems for the treatment of many degenerative as well as traumatic neurological disorders is presented in this paper. Due to the advances in micro and nano sensors and wireless systems, the biomedical sensors have the potential to revolutionize many areas in healthcare systems. The integration of nanodevices with neurons that are in communication with smart microsensor systems has great potential in the treatment of many neurodegenerative brain disorders. It is well established that patients suffering from either Parkinson"s disease (PD) or Epilepsy have benefited from the advantages of implantable devices in the neural pathways of the brain to alter the undesired signals thus restoring proper function. In addition, implantable devices have successfully blocked pain signals and controlled various pelvic muscles in patients with urinary and fecal incontinence. Even though the existing technology has made a tremendous impact on controlling the deleterious effects of disease, it is still in its infancy. This paper presents solutions of many problems of today's implantable and neural-electronic interface devices by combining nanowires and microelectronics with BioMEMS and applying them at cellular level for the development of a total wireless feedback control system. The only device that will actually be implanted in this research is the electrodes. All necessary controllers will be housed in accessories that are outside the body that communicate with the implanted electrodes through tiny inductively-coupled antennas. A Parkinson disease patient can just wear a hat-system close to the implantable neural probe so that the patient is free to move around, while the sensors continually monitor, record, transmit all vital information to health care specialist. In the event of a problem, the system provides an early warning to the patient while they are still mobile thus providing them the opportunity to react and

  17. Emerging Synergy between Nanotechnology and Implantable Biosensors: A Review

    PubMed Central

    Vaddiraju, Santhisagar; Tomazos, Ioannis; Burgess, Diane J; Jain, Faquir C; Papadimitrakopoulos, Fotios

    2010-01-01

    The development of implantable biosensors for continuous monitoring of metabolites is an area of sustained scientific and technological interest. On the other hand, nanotechnology, a discipline which deals with the properties of materials at the nanoscale, is developing as a potent tool to enhance the performance of these biosensors. This article reviews the current state of implantable biosensors, highlighting the synergy between nanotechnology and sensor performance. Emphasis is placed on the electrochemical method of detection in light of its widespread usage and substantial nanotechnology-based improvements in various aspects of electrochemical biosensor performance. Finally, issues regarding toxicity and biocompatibility of nanomaterials, along with future prospects for the application of nanotechnology in implantable biosensors, are discussed. PMID:20042326

  18. Chip-scale hermetic feedthroughs for implantable bionics.

    PubMed

    Guenther, Thomas; Dodds, Christopher W D; Lovell, Nigel H; Suaning, Gregg J

    2011-01-01

    Most implantable medical devices such as cochlear implants and visual prostheses require protection of the stimulating electronics. This is achieved by way of a hermetic feedthrough system which typically features three important attributes: biocompatibility with the human body, device hermeticity and density of feedthrough conductors. On the quest for building a visual neuroprosthesis, a high number of stimulating channels is required. This has encouraged new technologies with higher rates of production yield and further miniaturization. An Al(2)O(3) based feedthrough system has been developed comprising up to 20 platinum feedthroughs per square millimeter. Ceramics substrates are shown to have leak rates below 1 × 10(-12) atm × cc/s, thus exceeding the resolution limits of most commercially available leak detectors. A sheet resistance of 0.05 Ω can be achieved. This paper describes the design, fabrication process and hermeticity testing of high density feedthroughs for use in neuroprosthetic implants.

  19. Deep Trench Doping by Plasma Immersion Ion Implantation in Silicon

    SciTech Connect

    Nizou, S.; Vervisch, V.; Etienne, H.; Torregrosa, F.; Roux, L.; Ziti, M.; Alquier, D.; Roy, M.

    2006-11-13

    The realization of three dimensional (3D) device structures remains a great challenge in microelectronics. One of the main technological breakthroughs for such devices is the ability to control dopant implantation along silicon trench sidewalls. Plasma Immersion Ion Implantation (PIII) has shown its wide efficiency for specific doping processing in semiconductor applications. In this work, we propose to study the capability of PIII method for large scale silicon trench doping. Ultra deep trenches with high aspect ratio were etched on 6'' N type Si wafers. Wafers were then implanted with a PIII Pulsion system using BF3 gas source at various pressures and energies. The obtained results evidence that PIII can be used and are of grateful help to define optimized processing conditions to uniformly dope silicon trench sidewalls through the wafers.

  20. Concepts and designs of ion implantation equipment for semiconductor processing

    NASA Astrophysics Data System (ADS)

    Rose, Peter H.; Ryding, Geoffrey

    2006-11-01

    Manufacturing ion implantation equipment for doping semiconductors has grown into a two billion dollar business. The accelerators developed for nuclear physics research and isotope separation provided the technology from which ion implanters have been developed but the unique requirements of the semiconductor industry defined the evolution of the architecture of these small accelerators. Key elements will be described including ion generation and beam transport systems as well as the techniques used to achieve uniform doping over large wafers. The wafers are processed one at a time or in batches and are moved in and out of the vacuum by automated handling systems. The productivity of an implanter is of economic importance and there is continuing need to increase the usable beam current especially at low energies.

  1. [Imaging in silicone breast implantation].

    PubMed

    Gielens, Maaike P M; Koolen, Pieter G L; Hermens, Roland A E C; Rutten, Matthieu J C M

    2013-01-01

    Recently, there have been concerns regarding the use of breast implants from Poly Implant Prothèse (PIP, Seyne sur Mer, France) for breast augmentation due to their tendency to rupture and the possibility of having toxic contents. MRI using a specific silicone-sensitive sequence has proven to be the most sensitive and specific technique in the detection of intra- and extracapsular implant rupture. However, given its high costs, it is important that this technique is used sparingly. In this clinical lesson, we compare the sensitivity and specificity of mammography, ultrasound, CT and MRI for the detection of breast implant rupture. Based on two cases, a diagnostic approach is given in order to reduce health care costs. PMID:24252405

  2. Implants for draining neovascular glaucoma.

    PubMed Central

    Molteno, A C; Van Rooyen, M M; Bartholomew, R S

    1977-01-01

    The implant design, surgical technique, and pharmacological methods of controlling bleb fibrosis, used to treat neovascular glaucoma, are described, together with the results of 14 operations performed on 12 eyes. Images PMID:843508

  3. Dental-Implantate und ihre Werkstoffe

    NASA Astrophysics Data System (ADS)

    Newesely, Heinrich

    1983-07-01

    Some new trends in materials for dental implants, which also effect in the operative techniques and implant design, are described. Advantages and shortcomings of the different material types are exemplified and correlated with their bioinert resp. bioactive functions. The practical interest in metallic implants focussed in titanium resp. oxide ceramics in the ceramic field, whereas the special goal of implant research follows from the improvement of the bioactive principle with loaded calcium phosphate implants.

  4. Cochlear implants in young children.

    PubMed

    Niparko, John K; Blankenhorn, Rebecca

    2003-01-01

    The cochlear implant is best characterized as a device that provides access to the sound environment. The device enables the hearing pathway to respond to environmental and speech sounds, providing informational cues from the surroundings and from others that may escape visual detection. As the developmental effects of a profound hearing loss are multiple, cochlear implants have been applied to ever younger children in an attempt to promote a more normal level of developmental learning through audition. In deafness, transducer elements of the inner ear fail to trigger auditory nerve afferent nerves in the presence of sound input. However, large reserves of afferent fibers exist even in the auditory nerve of a profoundly deaf patient. Furthermore, these nerve fibers retain the ability to respond to prosthetic activation. Through developmental learning in the early, formative years, auditory centers of the brain appear capable of processing information from the implant to provide speech comprehension and oral language development. Multichannel implants have replaced original single channel designs. multichannel devices enable larger percentages of recipients to recognize the spoken word without visual cues because they provide spectral information in addition to temporal and intensity cues. Testing under conditions of auditory (implant)-only input reveals significant open-set speech understanding capabilities in more than 75% of children after three years of device use. The benefit provided by implants may vary with a number of conditions including: hearing history, age of deafness onset, age at implantation, etiology of deafness, linguistic abilities, and the presence of a motivated system of support of oral language development. Patient variables should be given individual consideration in judging candidacy for a cochlear implant and in planning rehabilitative and education services after surgery and activation of the device.

  5. Tegress™ Urethral Implant Phase III Clinical Experience and Product Uniqueness

    PubMed Central

    Dmochowski, Roger R

    2005-01-01

    Advances in materials technology, coupled with a heightened understanding of wound healing and tissue-materials interactions in the lower urinary tract, have led to the development of a variety of new urethral bulking agents that are expected to be available in the near future. Experience with such bulking agents continues to grow and study results are disseminated as more clinical trials are initiated and completed. The intention of this report is to review the characteristics and initial clinical results for one of these new agents: Tegress™ Urethral Implant (C. R. Bard, Inc., Murray Hill, NJ). This material, with unique phase-change properties upon exposure to body temperature fluids, offers ease of injection and requires less volume for clinical effect than bovine collagen. Additionally, Tegress Urethral Implant performance in clinical trials has suggested improved durability and correspondingly higher continence and improvement rates versus bovine collagen. As these materials evolve, an understanding of preferential implant techniques is being gained also. Delivery method and implant site may prove to substantially alter the biologic activity of these compounds. As outlined in this review, experience with Tegress Implant resulted in changes in delivery technique that translated into improved materials and tissue interaction. PMID:16985873

  6. The Esteem System: a totally implantable hearing device.

    PubMed

    Maurer, J; Savvas, E

    2010-01-01

    The Esteem totally implantable active middle ear implant is a new technology to augment hearing in patients suffering from moderate-to-severe and severe sensorineural hearing loss. In contrast to conventional (acoustic) hearing aids, the system uses two piezoelectric transducers (PZTs). PZTs are used as the sensor and driver to replace the function of the middle ear. Sound is received via a PZT sensor that picks up eardrum vibrations, following the piezoelectric principle, and transforms them into an electric signal. This signal is filtered, modified, amplified and transferred to a PZT driver, which mechanically drives the stapes and thereby the inner ear. The sound processor also contains a power source, which is an implantable lithium iodide battery. All components of the hearing restoration system are totally implantable to offer good sound fidelity and reduce hearing aid stigma caused by the visibility of conventional and semi-implantable hearing systems. Our experience shows that this system can provide considerable benefit to patients with sensorineural hearing loss.

  7. Neurobiochemical changes in the vicinity of a nanostructured neural implant

    PubMed Central

    Bérces, Zsófia; Tóth, Kinga; Márton, Gergely; Pál, Ildikó; Kováts-Megyesi, Bálint; Fekete, Zoltán; Ulbert, István; Pongrácz, Anita

    2016-01-01

    Neural interface technologies including recording and stimulation electrodes are currently in the early phase of clinical trials aiming to help patients with spinal cord injuries, degenerative disorders, strokes interrupting descending motor pathways, or limb amputations. Their lifetime is of key importance; however, it is limited by the foreign body response of the tissue causing the loss of neurons and a reactive astrogliosis around the implant surface. Improving the biocompatibility of implant surfaces, especially promoting neuronal attachment and regeneration is therefore essential. In our work, bioactive properties of implanted black polySi nanostructured surfaces (520–800 nm long nanopillars with a diameter of 150–200 nm) were investigated and compared to microstructured Si surfaces in eight-week-long in vivo experiments. Glial encapsulation and local neuronal cell loss were characterised using GFAP and NeuN immunostaining respectively, followed by systematic image analysis. Regarding the severity of gliosis, no significant difference was observed in the vicinity of the different implant surfaces, however, the number of surviving neurons close to the nanostructured surface was higher than that of the microstructured ones. Our results imply that the functionality of implanted microelectrodes covered by Si nanopillars may lead to improved long-term recordings. PMID:27775024

  8. High concentration of deuterium in palladium from plasma ion implantation

    SciTech Connect

    Uhm, H.S.; Lee, W.M. )

    1991-11-01

    Based on a theoretical calculation, a new scheme to increase deuterium density in palladium over its initial value is presented. This deuterium enrichment scheme makes use of plasma ion implantation. A cylindrical palladium rod (target) preloaded with deuterium atoms, coated with a diffusion-barrier material, is immersed in a deuterium plasma. The palladium rod is connected to a high-power modulator which provides a series of negative-voltage pulses. During these negative pulses, deuterium ions fall into the target, penetrate the diffusion barrier, and are implanted inside the palladium. For reasonable system parameters allowed by present technology, it is found from theoretical calculations that the saturation deuterium density after prolonged ion implantation can be several times the palladium atomic number density. Assuming an initial deuterium density, {ital n}{sub 0}=4{times}10{sup 22} cm{sup {minus}3}, it is also found that the deuterium density in palladium can triple its original value within a few days of the ion implantation for a reasonable target size. Because of the small diffusion coefficient in palladium, the incoming ions do not diffuse quickly inward, thereby accumulating near the target surface at the beginning of the implantation.

  9. A Universal Delivery System for Percutaneous Heart Valve Implantation.

    PubMed

    Bartosch, Marco; Peters, Heiner; Spriestersbach, Hendrik; O H-Ici, Darach; Berger, Felix; Schmitt, Boris

    2016-09-01

    Transcatheter heart valve implantation is an emerging technology and an alternative to surgical valve replacement. Most existing systems consist of valves sewn into balloon-expandable stents with a delivery catheter functioning with the specific valve only. The aim of this study was to develop a universally applicable delivery system (DS) for plane stents, valves sewn into both balloon-expandable and self-expandable stents and feasible for use with different access routes. A DS was designed and manufactured in five different diameters. The requirements were derived from the implants, the implantation technique and the cardiovascular geometry of the experimental sheep. The combination of a self-expandable Nitinol stent and a jugular access point represented the major challenge as both flexibility and rigidity of the DS were required. To fulfill these contradicting mechanical properties the sheaths were comprised of a soft outer polymer tube with a stainless steel coiled spring inside. Tissue-engineered and pericardial pulmonary valves were implanted. Also polymeric and balloon-expandable stents were delivered to various positions in the vascular system. The initial success rate was 70.5%. After refinement of the DS, a success rate of 83.3% was achieved with the remaining failed implantations resulting from inadequate sizes of the prostheses. PMID:26864537

  10. Transcriptomic Analysis of the Porcine Endometrium during Embryo Implantation.

    PubMed

    Lin, Haichao; Wang, Huaizhong; Wang, Yanping; Liu, Chang; Wang, Cheng; Guo, Jianfeng

    2015-01-01

    In pigs, successful embryo implantation is an important guarantee for producing litter size, and early embryonic loss occurring on day 12-30 of gestation critically affects the potential litter size. The implantation process is regulated by the expression of numerous genes, so comprehensive analysis of the endometrium is necessary. In this study, RNA sequencing (RNA-Seq) technology is used to analyze endometrial tissues during early pregnancy. We investigated the changes of gene expression between three stages (day 12, 18, and 25) by multiple comparisons. There were 1557, 8951, and 2345 differentially expressed genes (DEGs) revealed between the different periods of implantation. We selected several genes for validation by the use of quantitative real-time RT-PCR. Bioinformatic analysis of differentially expressed genes in the endometrium revealed a number of biological processes and pathways potentially involved in embryo implantation in the pig, most noticeably cell proliferation, regulation of immune response, interaction of cytokine-cytokine receptors, and cell adhesion. These results showed that specific gene expression patterns reflect the different functions of the endometrium in three stages (maternal recognition, conceptus attachment, and embryo implantation). This study identified comprehensive transcriptomic profile in the porcine endometrium and thus could be a foundation for targeted studies of genes and pathways potentially involved in abnormal endometrial receptivity and embryo loss in early pregnancy. PMID:26703736

  11. Transcriptomic Analysis of the Porcine Endometrium during Embryo Implantation

    PubMed Central

    Lin, Haichao; Wang, Huaizhong; Wang, Yanping; Liu, Chang; Wang, Cheng; Guo, Jianfeng

    2015-01-01

    In pigs, successful embryo implantation is an important guarantee for producing litter size, and early embryonic loss occurring on day 12–30 of gestation critically affects the potential litter size. The implantation process is regulated by the expression of numerous genes, so comprehensive analysis of the endometrium is necessary. In this study, RNA sequencing (RNA-Seq) technology is used to analyze endometrial tissues during early pregnancy. We investigated the changes of gene expression between three stages (day 12, 18, and 25) by multiple comparisons. There were 1557, 8951, and 2345 differentially expressed genes (DEGs) revealed between the different periods of implantation. We selected several genes for validation by the use of quantitative real-time RT-PCR. Bioinformatic analysis of differentially expressed genes in the endometrium revealed a number of biological processes and pathways potentially involved in embryo implantation in the pig, most noticeably cell proliferation, regulation of immune response, interaction of cytokine-cytokine receptors, and cell adhesion. These results showed that specific gene expression patterns reflect the different functions of the endometrium in three stages (maternal recognition, conceptus attachment, and embryo implantation). This study identified comprehensive transcriptomic profile in the porcine endometrium and thus could be a foundation for targeted studies of genes and pathways potentially involved in abnormal endometrial receptivity and embryo loss in early pregnancy. PMID:26703736

  12. Ion implanted dielectric elastomer circuits

    NASA Astrophysics Data System (ADS)

    O'Brien, Benjamin M.; Rosset, Samuel; Anderson, Iain A.; Shea, Herbert R.

    2013-06-01

    Starfish and octopuses control their infinite degree-of-freedom arms with panache—capabilities typical of nature where the distribution of reflex-like intelligence throughout soft muscular networks greatly outperforms anything hard, heavy, and man-made. Dielectric elastomer actuators show great promise for soft artificial muscle networks. One way to make them smart is with piezo-resistive Dielectric Elastomer Switches (DES) that can be combined with artificial muscles to create arbitrary digital logic circuits. Unfortunately there are currently no reliable materials or fabrication process. Thus devices typically fail within a few thousand cycles. As a first step in the search for better materials we present a preliminary exploration of piezo-resistors made with filtered cathodic vacuum arc metal ion implantation. DES were formed on polydimethylsiloxane silicone membranes out of ion implanted gold nano-clusters. We propose that there are four distinct regimes (high dose, above percolation, on percolation, low dose) in which gold ion implanted piezo-resistors can operate and present experimental results on implanted piezo-resistors switching high voltages as well as a simple artificial muscle inverter. While gold ion implanted DES are limited by high hysteresis and low sensitivity, they already show promise for a range of applications including hysteretic oscillators and soft generators. With improvements to implanter process control the promise of artificial muscle circuitry for soft smart actuator networks could become a reality.

  13. Biomechanics of Corneal Ring Implants

    PubMed Central

    2015-01-01

    Purpose: To evaluate the biomechanics of corneal ring implants by providing a related mathematical theory and biomechanical model for the treatment of myopia and keratoconus. Methods: The spherical dome model considers the inhomogeneity of the tunica of the eye, dimensions of the cornea, lamellar structure of the corneal stroma, and asphericity of the cornea. It is used in this study for calculating a strengthening factor sf for the characterization of different ring-shaped corneal implant designs. The strengthening factor is a measure of the amount of strengthening of the cornea induced by the implant. Results: For ring segments and incomplete rings, sf = 1.0, which indicates that these implants are not able to strengthen the cornea. The intracorneal continuous complete ring (MyoRing) has a strengthening factor of up to sf = 3.2. The MyoRing is, therefore, able to strengthen the cornea significantly. Conclusions: The result of the presented biomechanical analysis of different ring-shaped corneal implant designs can explain the different postoperative clinical results of different implant types in myopia and keratoconus. PMID:26312619

  14. [Implant-associated infections - Diagnostics].

    PubMed

    Renz, N; Müller, M; Perka, C; Trampuz, A

    2016-10-01

    The diagnosis of implant-associated infections is challenging as chronic low-grade infections often only manifest as subtle clinical symptoms. Clinical evaluation, patient history, imaging, histopathological and microbiological examinations build the cornerstones of the diagnostics for implant-associated infections. New onset of pain at rest, local symptoms at the surgical site and early loosening of the prosthesis or pseudarthrosis should raise suspicion for an infection and prompt further evaluation. Percutaneous sinus tracts, purulent wound secretions and skin erosions with exposure of the implant are certain signs of implant-associated infections. Elevated C‑reactive protein levels in blood support the diagnosis of infection but are neither sufficient sensitive nor specific to confirm or exclude infection. Preoperative antibiotic therapy interferes with the diagnostic evaluation and should be avoided. In periprosthetic joint infections, joint aspiration with determination of the leukocyte count and microbiological examination is a crucial first diagnostic step. Through microbiological and histopathological examinations of intraoperative tissue samples, as well as sonication of explanted implants, the causative pathogen can be identified in most cases. In osteosynthesis-associated infections imaging plays a key role to detect non-union, infection callus, sequester, peri-implant osteolysis and extraosseous and intramedullary pathologies. In prosthetic joint infections imaging provides information about the position and stability of the prosthesis. In case of hematogenic infection seeding from a distant focus, blood cultures should be sampled, followed by a meticulous investigation of potential primary focus of infection, depending on the causative agent.

  15. Retinal implants: a systematic review.

    PubMed

    Chuang, Alice T; Margo, Curtis E; Greenberg, Paul B

    2014-07-01

    Retinal implants present an innovative way of restoring sight in degenerative retinal diseases. Previous reviews of research progress were written by groups developing their own devices. This systematic review objectively compares selected models by examining publications describing five representative retinal prostheses: Argus II, Boston Retinal Implant Project, Epi-Ret 3, Intelligent Medical Implants (IMI) and Alpha-IMS (Retina Implant AG). Publications were analysed using three criteria for interim success: clinical availability, vision restoration potential and long-term biocompatibility. Clinical availability: Argus II is the only device with FDA approval. Argus II and Alpha-IMS have both received the European CE Marking. All others are in clinical trials, except the Boston Retinal Implant, which is in animal studies. Vision restoration: resolution theoretically correlates with electrode number. Among devices with external cameras, the Boston Retinal Implant leads with 100 electrodes, followed by Argus II with 60 electrodes and visual acuity of 20/1262. Instead of an external camera, Alpha-IMS uses a photodiode system dependent on natural eye movements and can deliver visual acuity up to 20/546. Long-term compatibility: IMI offers iterative learning; Epi-Ret 3 is a fully intraocular device; Alpha-IMS uses intraocular photosensitive elements. Merging the results of these three criteria, Alpha-IMS is the most likely to achieve long-term success decades later, beyond current clinical availability. PMID:24403565

  16. [Implantable hemodynamic monitoring devices].

    PubMed

    Seifert, M; Butter, C

    2015-11-01

    Heart failure is one of the most frequent diagnoses in hospital admissions in Germany. In the majority of these admissions acute decompensation of an already existing chronic heart failure is responsible. New mostly wireless and remote strategies for monitoring, titration, adaptation and optimization are the focus for improvement of the treatment of heart failure patients and the poor prognosis. The implantation of hemodynamic monitoring devices follows the hypothesis that significant changes in hemodynamic parameters occur before the occurrence of acute decompensation requiring readmission. Three different hemodynamic monitoring devices have so far been investigated in clinical trials employing right ventricular pressure, left atrial pressure and pulmonary artery pressure monitoring. Only one of these systems, the CardioMENS™ HF monitoring system, demonstrated a significant reduction of hospitalization due to heart failure over 6 months in the CHAMPION trial. The systematic adaptation of medication in the CHAMPION trial significantly differed from the usual care of the control arm over 6 months. This direct day to day management of diuretics is currently under intensive investigation; however, further studies demonstrating a positive effect on mortality are needed before translation of this approach into guidelines. Without this evidence a further implementation of pressure monitoring into currently used devices and justification of the substantial technical and personnel demands are not warranted.

  17. Imaging of common breast implants and implant-related complications: A pictorial essay

    PubMed Central

    Shah, Amisha T; Jankharia, Bijal B

    2016-01-01

    The number of women undergoing breast implant procedures is increasing exponentially. It is, therefore, imperative for a radiologist to be familiar with the normal and abnormal imaging appearances of common breast implants. Diagnostic imaging studies such as mammography, ultrasonography, and magnetic resonance imaging are used to evaluate implant integrity, detect abnormalities of the implant and its surrounding capsule, and detect breast conditions unrelated to implants. Magnetic resonance imaging of silicone breast implants, with its high sensitivity and specificity for detecting implant rupture, is the most reliable modality to asses implant integrity. Whichever imaging modality is used, the overall aim of imaging breast implants is to provide the pertinent information about implant integrity, detect implant failures, and to detect breast conditions unrelated to the implants, such as cancer. PMID:27413269

  18. Why are mini-implants lost: The value of the implantation technique!

    PubMed Central

    Romano, Fabio Lourenço; Consolaro, Alberto

    2015-01-01

    The use of mini-implants have made a major contribution to orthodontic treatment. Demand has aroused scientific curiosity about implant placement procedures and techniques. However, the reasons for instability have not yet been made totally clear. The aim of this article is to establish a relationship between implant placement technique and mini-implant success rates by means of examining the following hypotheses: 1) Sites of poor alveolar bone and little space between roots lead to inadequate implant placement; 2) Different sites require mini-implants of different sizes! Implant size should respect alveolar bone diameter; 3) Properly determining mini-implant placement site provides ease for implant placement and contributes to stability; 4) The more precise the lancing procedures, the better the implant placement technique; 5) Self-drilling does not mean higher pressures; 6) Knowing where implant placement should end decreases the risk of complications and mini-implant loss. PMID:25741821

  19. A Fully-Implantable Cochlear Implant SoC with Piezoelectric Middle-Ear Sensor and Arbitrary Waveform Neural Stimulation

    PubMed Central

    Yip, Marcus; Jin, Rui; Nakajima, Hideko Heidi; Stankovic, Konstantina M.; Chandrakasan, Anantha P.

    2015-01-01

    A system-on-chip for an invisible, fully-implantable cochlear implant is presented. Implantable acoustic sensing is achieved by interfacing the SoC to a piezoelectric sensor that detects the sound-induced motion of the middle ear. Measurements from human cadaveric ears demonstrate that the sensor can detect sounds between 40 and 90 dB SPL over the speech bandwidth. A highly-reconfigurable digital sound processor enables system power scalability by reconfiguring the number of channels, and provides programmable features to enable a patient-specific fit. A mixed-signal arbitrary waveform neural stimulator enables energy-optimal stimulation pulses to be delivered to the auditory nerve. The energy-optimal waveform is validated with in-vivo measurements from four human subjects which show a 15% to 35% energy saving over the conventional rectangular waveform. Prototyped in a 0.18 μm high-voltage CMOS technology, the SoC in 8-channel mode consumes 572 μW of power including stimulation. The SoC integrates implantable acoustic sensing, sound processing, and neural stimulation on one chip to minimize the implant size, and proof-of-concept is demonstrated with measurements from a human cadaver ear. PMID:26251552

  20. The design and production of Ti-6Al-4V ELI customized dental implants

    NASA Astrophysics Data System (ADS)

    Chahine, Gilbert; Koike, Mari; Okabe, Toru; Smith, Pauline; Kovacevic, Radovan

    2008-11-01

    This paper addresses the production of customized Ti-6Al-4V ELI dental implants via electron beam melting (EBM). The melting of Ti-6Al-4V ELI powder produces implants with great biocompatibility, fi ne mechanical performance, and a high bone ingrowth potential. The EBM technology is used to produce one-component dental implants that mimic the exact shape of the patient’s tooth, replacing the traditional, three-component, “screw-like” standardized dental implants currently used. The new generation of implants provides the possibility of simplifying pre-insertion procedures leading to faster healing time, and the potential of better and stronger osseointegration, specifi cally through incorporating lattice structure design.

  1. Optima XE Single Wafer High Energy Ion Implanter

    SciTech Connect

    Satoh, Shu; Ferrara, Joseph; Bell, Edward; Patel, Shital; Sieradzki, Manny

    2008-11-03

    The Optima XE is the first production worthy single wafer high energy implanter. The new system combines a state-of-art single wafer endstation capable of throughputs in excess of 400 wafers/hour with a production-proven RF linear accelerator technology. Axcelis has been evolving and refining RF Linac technology since the introduction of the NV1000 in 1986. The Optima XE provides production worthy beam currents up to energies of 1.2 MeV for P{sup +}, 2.9 MeV for P{sup ++}, and 1.5 MeV for B{sup +}. Energies as low as 10 keV and tilt angles as high as 45 degrees are also available., allowing the implanter to be used for a wide variety of traditional medium current implants to ensure high equipment utilization. The single wafer endstation provides precise implant angle control across wafer and wafer to wafer. In addition, Optima XE's unique dose control system allows compensation of photoresist outgassing effects without relying on traditional pressure-based methods. We describe the specific features, angle control and dosimetry of the Optima XE and their applications in addressing the ever-tightening demands for more precise process controls and higher productivity.

  2. Biomechanical load analysis of cantilevered implant systems.

    PubMed

    Osier, J F

    1991-01-01

    Historically, dental implants have been placed in areas where quality bone exists. The maxillary sinus areas and mandibular canal proximities have been avoided. From these placements, various cantilevered prosthetic applications have emerged. This analysis uses static engineering principles to define the loads (i.e., forces) placed upon the implants. These principles make use of Newton's first and third laws of mechanics by summing the forces and moments to zero. These summations then generate mathematical equations and their algebraic solutions. Three implant systems are analyzed. The first is a two-implant system. The second is a three-implant cross-arch stabilized system usually found in mandibular replacements of lower full dentures. The third is a five-implant system which is identical to the three-implant cantilevered system but which uses implants in the first molar area, thereby negating the cantilevered load magnification of the three-implant design. These analyses demonstrate that, in a cantilevered application, the implant closest to the point of load application (usually the most posterior implant) takes the largest compressive load. Implants opposite the load application (generally the anterior implant) are in tension. These loads on the implants are normally magnified over the biting force and can easily reach 2 1/2 to five times the biting load.

  3. Materials for endosseous dental implants.

    PubMed

    Wataha, J C

    1996-02-01

    The goal of placement of endosseous dental implants is to achieve osseointegration or biointegration of the bone with the implant. A wide variety of materials has been used for these implants, but only a few promote osseointegration and biointegration. Titanium and titanium alloy (Ti6A14V) have been the most widely used of these materials. The surface oxide of titanium appears to be central to the ability of this material to osseointegrate. The oxide limits dissolution of elements and promotes the deposition of biological molecules which allow bone to exist as close as 30 A to the surface of the implant. The details of the ultrastructure of the gap between the implant and bone remain undefined, and the consequences of elements which are released on the interface over time are not known. These areas of investigation are particularly important in defining the differences between commercially pure titanium implants and those made of titanium, aluminium and vanadium. The epithelial interface between the gingiva and titanium appears to contain many of the structural characteristics of the native tooth-gingiva interface, but details are still vague. The connective tissue interface with the titanium appears to be one of tightly fitting tissues rather than adhesion. Ceramic coatings appear to improve the ingrowth of bone and promote chemical integration of the implant with the bone. The characteristics of these coatings are complex and affect the bony response, but the mechanisms remain obscure. The degradation of the coatings is an issue of particular controversy. Progress in dental implantology is likely to continue as the interface between the material and bone is more clearly understood, and biological molecules and artificial tissues are developed.

  4. Drug-eluting medical implants.

    PubMed

    Zilberman, Meital; Kraitzer, Amir; Grinberg, Orly; Elsner, Jonathan J

    2010-01-01

    Drug-eluting medical implants are actually active implants that induce healing effects, in addition to their regular task of support. This effect is achieved by controlled release of active pharmaceutical ingredients (API) into the surrounding tissue. In this chapter we focus on three types of drug-eluting devices: drug-eluting vascular stents, drug-eluting wound dressings and protein-eluting scaffolds for tissue regeneration, thus describing both internal and external implants. Each of these drug-eluting devices also presents an approach for solving the drug release issue. Most drug-eluting vascular stents are loaded with water-insoluble antiproliferative agents, and their diffusion from the device to the surrounding tissue is relatively slow. In contrast, most drug-eluting wound dressings are loaded with highly water-soluble antibacterial agents and the issue of fast release must therefore be addressed. Growth factor release from scaffolds for tissue regeneration offers a new approach of incorporating high-molecular-weight bioactive agents which are very sensitive to process conditions and preserve their activity during the preparation stage. The drug-eluting medical implants are described here in terms of matrix formats and polymers, incorporated drugs and their release profiles from the implants, and implant functioning. Basic elements, such as new composite core/shell fibers and structured films, can be used to build new antibiotic-eluting devices. As presented in this chapter, the effect of the processing parameters on the microstructure and the resulting drug release profiles, mechanical and physical properties, and other relevant properties, must be elucidated in order to achieve the desired properties. Newly developed implants and novel modifications of previously developed approaches have enhanced the tools available for creating clinically important biomedical applications.

  5. Multicomponent Implant Releasing Dexamethasone

    NASA Astrophysics Data System (ADS)

    Nikkola, L.; Vapalahti, K.; Ashammakhi, N.

    2008-02-01

    Several inflammatory conditions are usually treated with corticosteroids. There are various problems like side effects with traditional applications of steroids, e.g. topical, or systemic routes. Local drug delivery systems have been studied and developed to gain more efficient administration with fewer side effects. Earlier, we reported on developing Dexamethasone (DX) releasing biodegradable fibers. However, their drug release properties were not satisfactory in terms of onset of drug release. Thus, we assessed the development of multicomponent (MC) implant to enhance earlier drug release from such biodegradable fibers. Poly (lactide-co-glycolide) (PLGA) and 2 wt-% and 8 wt-% DX were compounded and extruded with twin-screw extruder to form of fibers. Some of the fibers were sterilized to obtain a change in drug release properties. Four different fiber classes were studied: 2 wt-%, 8 wt-%, sterilized 2 wt-%, and sterilized 8 wt-%. 3×4 different DX-releasing fibers were then heat-pressed to form one multicomponent rod. Half of the rods where sterilized. Drug release was measured from initial fibers and multicomponent rods using a UV/VIS spectrometer. Shear strength and changes in viscosity were also measured. Drug release studies showed that drug release commenced earlier from multicomponent rods than from component fibers. Drug release from multicomponent rods lasted from day 30 to day 70. The release period of sterilized rods extended from day 23 to day 57. When compared to the original component fibers, the drug release from MC rods commenced earlier. The initial shear strength of MC rods was 135 MPa and decreased to 105 MPa during four weeks of immersion in phosphate buffer solution. Accordingly, heat pressing has a positive effect on drug release. After four weeks in hydrolysis, no disintegration was observed.

  6. Medical implants and methods of making medical implants

    SciTech Connect

    Shaw, Wendy J; Yonker, Clement R; Fulton, John L; Tarasevich, Barbara J; McClain, James B; Taylor, Doug

    2014-09-16

    A medical implant device having a substrate with an oxidized surface and a silane derivative coating covalently bonded to the oxidized surface. A bioactive agent is covalently bonded to the silane derivative coating. An implantable stent device including a stent core having an oxidized surface with a layer of silane derivative covalently bonded thereto. A spacer layer comprising polyethylene glycol (PEG) is covalently bonded to the layer of silane derivative and a protein is covalently bonded to the PEG. A method of making a medical implant device including providing a substrate having a surface, oxidizing the surface and reacting with derivitized silane to form a silane coating covalently bonded to the surface. A bioactive agent is then covalently bonded to the silane coating. In particular instances, an additional coating of bio-absorbable polymer and/or pharmaceutical agent is deposited over the bioactive agent.

  7. Ion implantation of silicon in gallium arsenide: Damage and annealing characterizations

    NASA Astrophysics Data System (ADS)

    Pribat, D.; Dieumegard, D.; Croset, M.; Cohen, C.; Nipoti, R.; Siejka, J.; Bentini, G. G.; Correra, L.; Servidori, M.

    1983-05-01

    The purpose of this work is twofold: (i) to study the damage induced by ion implantation, with special attention to low implanted doses; (ii) to study the efficiency of annealing techniques — particularly incoherent light annealing — in order to relate the electrical activity of implanted atoms to damage annealing. We have used three methods to study the damage induced by ion implantation: (1) RBS (or nuclear reactions) in random or in channeling geometry (2) RX double crystal diffractometry and (3) electrical measurements (free carrier profiling). Damage induced by silicon implantation at doses >10 14at/cm 2 can be monitored by all three techniques. However, the sensitivity of RBS is poor and hence this technique is not useful for low implantation doses. As device technology requires dopant levels in the range of 5 × 10 12 atoms/cm 2, we are particularly interested to the development of analytical techniques able to detect the damage at this implantation level. The sensitivity of such techniques was checked by studying homogeneously doped (5 × 10 16 e -/cm 3) and semi-insulating GaAs samples implanted with 3 × 10 12 silicon atoms/cm 2 at 150 keV. The substrate temperature during implantation was 200°C. The damage produced in these samples and its subsequent annealing are evidenced by strong changes in X-ray double crystal diffraction spectra. This method hence appears as a good monitoring technique. Annealing of the implanted layers has been performed using incoherent light sources (xenon lamps) either in flash or continuous conditions. Reference samples have also been thermally annealed (850°C, 20 min in capless conditions). The results are compared, and the electrical carrier profiles obtained after continuous incoherent light irradiation indicate that the implanted silicon atoms are almost dully activated. The advantages and disadvantages of incoherent light irradiation are discussed (surface oxidation, surface damage) in comparison with standard

  8. A living thick nanofibrous implant bifunctionalized with active growth factor and stem cells for bone regeneration.

    PubMed

    Eap, Sandy; Keller, Laetitia; Schiavi, Jessica; Huck, Olivier; Jacomine, Leandro; Fioretti, Florence; Gauthier, Christian; Sebastian, Victor; Schwinté, Pascale; Benkirane-Jessel, Nadia

    2015-01-01

    New-generation implants focus on robust, durable, and rapid tissue regeneration to shorten recovery times and decrease risks of postoperative complications for patients. Herein, we describe a new-generation thick nanofibrous implant functionalized with active containers of growth factors and stem cells for regenerative nanomedicine. A thick electrospun poly(ε-caprolactone) nanofibrous implant (from 700 μm to 1 cm thick) was functionalized with chitosan and bone morphogenetic protein BMP-7 as growth factor using layer-by-layer technology, producing fish scale-like chitosan/BMP-7 nanoreservoirs. This extracellular matrix-mimicking scaffold enabled in vitro colonization and bone regeneration by human primary osteoblasts, as shown by expression of osteocalcin, osteopontin, and bone sialoprotein (BSPII), 21 days after seeding. In vivo implantation in mouse calvaria defects showed significantly more newly mineralized extracellular matrix in the functionalized implant compared to a bare scaffold after 30 days' implantation, as shown by histological scanning electron microscopy/energy dispersive X-ray microscopy study and calcein injection. We have as well bifunctionalized our BMP-7 therapeutic implant by adding human mesenchymal stem cells (hMSCs). The activity of this BMP-7-functionalized implant was again further enhanced by the addition of hMSCs to the implant (living materials), in vivo, as demonstrated by the analysis of new bone formation and calcification after 30 days' implantation in mice with calvaria defects. Therefore, implants functionalized with BMP-7 nanocontainers associated with hMSCs can act as an accelerator of in vivo bone mineralization and regeneration. PMID:25709432

  9. A living thick nanofibrous implant bifunctionalized with active growth factor and stem cells for bone regeneration

    PubMed Central

    Eap, Sandy; Keller, Laetitia; Schiavi, Jessica; Huck, Olivier; Jacomine, Leandro; Fioretti, Florence; Gauthier, Christian; Sebastian, Victor; Schwinté, Pascale; Benkirane-Jessel, Nadia

    2015-01-01

    New-generation implants focus on robust, durable, and rapid tissue regeneration to shorten recovery times and decrease risks of postoperative complications for patients. Herein, we describe a new-generation thick nanofibrous implant functionalized with active containers of growth factors and stem cells for regenerative nanomedicine. A thick electrospun poly(ε-caprolactone) nanofibrous implant (from 700 μm to 1 cm thick) was functionalized with chitosan and bone morphogenetic protein BMP-7 as growth factor using layer-by-layer technology, producing fish scale-like chitosan/BMP-7 nanoreservoirs. This extracellular matrix-mimicking scaffold enabled in vitro colonization and bone regeneration by human primary osteoblasts, as shown by expression of osteocalcin, osteopontin, and bone sialoprotein (BSPII), 21 days after seeding. In vivo implantation in mouse calvaria defects showed significantly more newly mineralized extracellular matrix in the functionalized implant compared to a bare scaffold after 30 days’ implantation, as shown by histological scanning electron microscopy/energy dispersive X-ray microscopy study and calcein injection. We have as well bifunctionalized our BMP-7 therapeutic implant by adding human mesenchymal stem cells (hMSCs). The activity of this BMP-7-functionalized implant was again further enhanced by the addition of hMSCs to the implant (living materials), in vivo, as demonstrated by the analysis of new bone formation and calcification after 30 days’ implantation in mice with calvaria defects. Therefore, implants functionalized with BMP-7 nanocontainers associated with hMSCs can act as an accelerator of in vivo bone mineralization and regeneration. PMID:25709432

  10. Implantable biomedical devices on bioresorbable substrates

    DOEpatents

    Rogers, John A; Kim, Dae-Hyeong; Omenetto, Fiorenzo; Kaplan, David L; Litt, Brian; Viventi, Jonathan; Huang, Yonggang; Amsden, Jason

    2014-03-04

    Provided herein are implantable biomedical devices, methods of administering implantable biomedical devices, methods of making implantable biomedical devices, and methods of using implantable biomedical devices to actuate a target tissue or sense a parameter associated with the target tissue in a biological environment. Each implantable biomedical device comprises a bioresorbable substrate, an electronic device having a plurality of inorganic semiconductor components supported by the bioresorbable substrate, and a barrier layer encapsulating at least a portion of the inorganic semiconductor components. Upon contact with a biological environment the bioresorbable substrate is at least partially resorbed, thereby establishing conformal contact between the implantable biomedical device and the target tissue in the biological environment.

  11. Cochlear Implantation in Older Adults

    PubMed Central

    Lin, Frank R.; Chien, Wade W.; Li, Lingsheng; Niparko, John K.; Francis, Howard W.

    2012-01-01

    Cochlear implants allow individuals with severe-to-profound hearing loss access to sound and spoken language. The number of older adults in the United States who are potential candidates for cochlear implantation is approximately 150,000 and will continue to increase with the aging of the population. Should cochlear implantation (CI) be routinely recommended for these older adults, and do these individuals benefit from CI? We reviewed our 12 year experience with cochlear implantation in adults ≥60 years (n = 445) at Johns Hopkins to investigate the impact of CI on speech understanding and to identify factors associated with speech performance. Complete data on speech outcomes at baseline and 1 year post-CI were available for 83 individuals. Our results demonstrate that cochlear implantation in adults ≥60 years consistently improved speech understanding scores with a mean increase of 60. 0% (S. D. 24. 1) on HINT sentences in quiet . The magnitude of the gain in speech scores was negatively associated with age at implantation such that for every increasing year of age at CI the gain in speech scores was 1. 3 percentage points less (95% CI: 0. 6 – 1. 9) after adjusting for age at hearing loss onset. Conversely, individuals with higher pre-CI speech scores (HINT scores between 40–60%) had significantly greater post-CI speech scores by a mean of 10. 0 percentage points (95% CI: 0. 4 – 19. 6) than those with lower pre-CI speech scores (HINT <40%) after adjusting for age at CI and age at hearing loss onset. These results suggest that older adult CI candidates who are younger at implantation and with higher preoperative speech scores obtain the highest speech understanding scores after cochlear implantation with possible implications for current Medicare policy. Finally, we provide an extended discussion of the epidemiology and impact of hearing loss in older adults. Future research of CI in older adults should expand beyond simple speech outcomes to take into

  12. SURFACE CHEMISTRY INFLUENCE IMPLANT BIOCOMPATIBILITY

    PubMed Central

    Thevenot, Paul; Hu, Wenjing; Tang, Liping

    2011-01-01

    Implantable medical devices are increasingly important in the practice of modern medicine. Unfortunately, almost all medical devices suffer to a different extent from adverse reactions, including inflammation, fibrosis, thrombosis and infection. To improve the safety and function of many types of medical implants, a major need exists for development of materials that evoked desired tissue responses. Because implant-associated protein adsorption and conformational changes thereafter have been shown to promote immune reactions, rigorous research efforts have been emphasized on the engineering of surface property (physical and chemical characteristics) to reduce protein adsorption and cell interactions and subsequently improve implant biocompatibility. This brief review is aimed to summarize the past efforts and our recent knowledge about the influence of surface functionality on protein:cell:biomaterial interactions. It is our belief that detailed understandings of bioactivity of surface functionality provide an easy, economic, and specific approach for the future rational design of implantable medical devices with desired tissue reactivity and, hopefully, wound healing capability. PMID:18393890

  13. PROPERTIES OF DEFECTS AND IMPLANTS IN Mg+ IMPLANTED SILICON CARBIDE

    SciTech Connect

    Jiang, Weilin; Zhu, Zihua; Varga, Tamas; Bowden, Mark E.; Manandhar, Sandeep; Roosendaal, Timothy J.; Hu, Shenyang Y.; Henager, Charles H.; Kurtz, Richard J.; Wang, Yongqiang

    2013-09-25

    As a candidate material for fusion reactor designs, silicon carbide (SiC) under high-energy neutron irradiation undergoes atomic displacement damage and transmutation reactions that create magnesium as one of the major metallic products. The presence of Mg and lattice disorder in SiC is expected to affect structural stability and degrade thermo-mechanical properties that could limit SiC lifetime for service. We have initiated a combined experimental and computational study that uses Mg+ ion implantation and multiscale modeling to investigate the structural and chemical effects in Mg implanted SiC and explore possible property degradation mechanisms.

  14. Optical power transfer and communication methods for wireless implantable sensing platforms

    NASA Astrophysics Data System (ADS)

    Mujeeb-U-Rahman, Muhammad; Adalian, Dvin; Chang, Chieh-Feng; Scherer, Axel

    2015-09-01

    Ultrasmall scale implants have recently attracted focus as valuable tools for monitoring both acute and chronic diseases. Semiconductor optical technologies are the key to miniaturizing these devices to the long-sought sub-mm scale, which will enable long-term use of these devices for medical applications. This can also enable the use of multiple implantable devices concurrently to form a true body area network of sensors. We demonstrate optical power transfer techniques and methods to effectively harness this power for implantable devices. Furthermore, we also present methods for optical data transfer from such implants. Simultaneous use of these technologies can result in miniaturized sensing platforms that can allow for large-scale use of such systems in real world applications.

  15. Optical power transfer and communication methods for wireless implantable sensing platforms.

    PubMed

    Mujeeb-U-Rahman, Muhammad; Adalian, Dvin; Chang, Chieh-Feng; Scherer, Axel

    2015-09-01

    Ultrasmall scale implants have recently attracted focus as valuable tools for monitoring both acute and chronic diseases. Semiconductor optical technologies are the key to miniaturizing these devices to the long-sought sub-mm scale, which will enable long-term use of these devices for medical applications. This can also enable the use of multiple implantable devices concurrently to form a true body area network of sensors. We demonstrate optical power transfer techniques and methods to effectively harness this power for implantable devices. Furthermore, we also present methods for optical data transfer from such implants. Simultaneous use of these technologies can result in miniaturized sensing platforms that can allow for large-scale use of such systems in real world applications. PMID:26405820

  16. Optical power transfer and communication methods for wireless implantable sensing platforms.

    PubMed

    Mujeeb-U-Rahman, Muhammad; Adalian, Dvin; Chang, Chieh-Feng; Scherer, Axel

    2015-09-01

    Ultrasmall scale implants have recently attracted focus as valuable tools for monitoring both acute and chronic diseases. Semiconductor optical technologies are the key to miniaturizing these devices to the long-sought sub-mm scale, which will enable long-term use of these devices for medical applications. This can also enable the use of multiple implantable devices concurrently to form a true body area network of sensors. We demonstrate optical power transfer techniques and methods to effectively harness this power for implantable devices. Furthermore, we also present methods for optical data transfer from such implants. Simultaneous use of these technologies can result in miniaturized sensing platforms that can allow for large-scale use of such systems in real world applications.

  17. Design features of implants for direct skeletal attachment of limb prostheses

    PubMed Central

    Pitkin, M.

    2013-01-01

    In direct skeletal attachment (DSA) of limb prostheses, a construct is implanted into an amputee’s residuum bone and protrudes out of the residuum’s skin. This technology represents an alternative to traditional suspension of prostheses via various socket systems, with clear indications when the sockets cannot be properly fitted. Contemporary DSA was invented in the 1990s, and several implant systems have been introduced since then. The current review is intended to compare the design features of implants for DSA whose use in humans or in animal studies has been reported in the literature. PMID:23554122

  18. Recessive dystrophic epidermolysis bullosa--oral rehabilitation using stereolithography and immediate endosseous implants.

    PubMed

    Oliveira, Marcio A; Ortega, Karem L; Martins, Fabiana M; Maluf, Paulo S Z; Magalhães, Marina G

    2010-01-01

    Dental management of patients with epi-dermolysis bullosa (EB) is challenging because of the severe soft tissue lesions associated with this disease. A case history is presented where two immediate endosseous implants were placed in the mandible of a patient with recessive dystrophic EB using computer-aided technology to plan the surgery and prosthetic rehabilitation. After a 24-month follow-up, the prosthesis was stable with healthy asymptomatic soft tissue around the implants. The stereolithographic model provides a precise and noninvasive copy of the mandibular and maxillary arches of patients with EB for rehabilitation of the dentition with immediate endosseous implants and a prosthesis.

  19. Implant rehabilitation in bruxism patient.

    PubMed

    Goiato, Marcelo Coelho; Sonego, Mariana Vilela; dos Santos, Daniela Micheline; da Silva, Emily Vivianne Freitas

    2014-06-06

    A white female patient presented to the university clinic to obtain implant retained prostheses. She had an edentulous maxillary jaw and presented three teeth with poor prognosis (33, 34 and 43). The alveolar bone and the surrounding tissues were healthy. The patient did not report any relevant medical history contraindicating routine dental treatment or implant surgery, but self-reported a dental history of asymptomatic nocturnal bruxism. The treatment plan was set and two Branemark protocols supported by six implants in each arch were installed after a 6-month healing period. A soft occlusal splint was made due to the patient's history of bruxism, and the lack of its use by the patient resulted in an acrylic fracture. The prosthesis was repaired and the importance of using the occlusal splint was restated. In the 4-year follow-up no fractures were reported.

  20. Implant rehabilitation in bruxism patient.

    PubMed

    Goiato, Marcelo Coelho; Sonego, Mariana Vilela; dos Santos, Daniela Micheline; da Silva, Emily Vivianne Freitas

    2014-01-01

    A white female patient presented to the university clinic to obtain implant retained prostheses. She had an edentulous maxillary jaw and presented three teeth with poor prognosis (33, 34 and 43). The alveolar bone and the surrounding tissues were healthy. The patient did not report any relevant medical history contraindicating routine dental treatment or implant surgery, but self-reported a dental history of asymptomatic nocturnal bruxism. The treatment plan was set and two Branemark protocols supported by six implants in each arch were installed after a 6-month healing period. A soft occlusal splint was made due to the patient's history of bruxism, and the lack of its use by the patient resulted in an acrylic fracture. The prosthesis was repaired and the importance of using the occlusal splint was restated. In the 4-year follow-up no fractures were reported. PMID:24907215

  1. Implant rehabilitation in bruxism patient

    PubMed Central

    Goiato, Marcelo Coelho; Sonego, Mariana Vilela; dos Santos, Daniela Micheline; da Silva, Emily Vivianne Freitas

    2014-01-01

    A white female patient presented to the university clinic to obtain implant retained prostheses. She had an edentulous maxillary jaw and presented three teeth with poor prognosis (33, 34 and 43). The alveolar bone and the surrounding tissues were healthy. The patient did not report any relevant medical history contraindicating routine dental treatment or implant surgery, but self-reported a dental history of asymptomatic nocturnal bruxism. The treatment plan was set and two Branemark protocols supported by six implants in each arch were installed after a 6-month healing period. A soft occlusal splint was made due to the patient's history of bruxism, and the lack of its use by the patient resulted in an acrylic fracture. The prosthesis was repaired and the importance of using the occlusal splint was restated. In the 4-year follow-up no fractures were reported. PMID:24907215

  2. [Signal processing in contour implants].

    PubMed

    Ormezzano, Y; Deleurme, C; Vormès, E; Frachet, B

    1990-01-01

    Signal processing by cochlear implants is aimed at transmitting all the acoustic information carried by the human voice, whether in its semantic, esthetic or affective aspects, as an electrical signal. The "translating" approach, which encodes the signal according to the characteristics of the sounds, can only be ideally used in multiple-canal implants. On the contrary, our experience with various single-canal prostheses shows that our patients choose one of these according to the comfort of the signal and to its reliability rather than to the complexity of signal processing: all prostheses produce approximately the same results, whatever the method implemented. The contour implant allows an easy, effective and well-tolerated fitting at low costs.

  3. MRI artefacts after Bonebridge implantation.

    PubMed

    Steinmetz, C; Mader, I; Arndt, S; Aschendorff, A; Laszig, R; Hassepass, F

    2014-07-01

    The new transcutaneous bone conduction implant (BCI) Bonebridge (BB, MED-EL) allows the skin to remain intact and therefore overcomes some issues related to percutaneous systems, such as skin reaction around the external screw and cosmetic complaints. According to manufacturer, BB is MRI conditional up to 1,5 Tesla (T). The artefact of the neurocranium after BB implantation is extensive as shown in the present report. This has to be taken into account when patients suffering conductive, mixed or single-sided hearing loss with candidacy for a BCI are counselled. In patients with comorbid intracranial tumour or other diseases of the brain that require imaging control scans with MRI percutaneous, BCI should be the implant of choice considering the very small artefact of the percutaneous screw in MRI.

  4. Treatment of Infected Facial Implants.

    PubMed

    Mohan, Kriti; Cox, Joshua A; Dickey, Ryan M; Gravina, Paula; Echo, Anthony; Izaddoost, Shayan A; Nguyen, Anh H

    2016-05-01

    Alloplastic facial implants have a wide range of uses to achieve the appropriate facial contour. A variety of materials such as metals, polymers, ceramics and synthetic injectable fillers are available to the reconstructive and aesthetic surgeon. Besides choosing the right surgical technique and the adequate material, the surgeon must be prepared to treat complications. Infection is an uncommon but serious complication that can cause displeasing consequences for the patient. There are few references in literature regarding treatment and management of facial implant-related infections. This study aims to discuss the role of biofilm in predisposing alloplastic materials to infection, to provide a review of literature, to describe our own institutional experience, and to define a patient care pathway for facial implant-associated infection. PMID:27152100

  5. Generator and Lead-Related Complications of Implantable Cardioverter Defibrillators

    PubMed Central

    Yaminisharif, Ahmad; Soofizadeh, Nader; Shafiee, Akbar; Kazemisaeid, Ali; Jalali, Arash; Vasheghani-Farahani, Ali

    2014-01-01

    Background: Increase in the number of patients treated with Implantable Cardioverter Defibrillator (ICD) requests more attention regarding its complications. Objectives: This study aimed to assess the generator- and lead-related complications at implantation and during follow-up in the patients who were treated with ICD for primary and secondary prevention reasons. Methods: We retrospectively reviewed 255 consecutive patients who underwent transvenous ICD implantation for the first time in a 7-year period and were followed-up for 3 years at Tehran Heart Center. The personal and clinical data of the patients as well as specific data on the ICD implantation were retrieved. The frequency of each of the complications was reported and the study variables were compared between the patients with and without complications using Student’s t-test and chi-square test where appropriate. P values less than 0.05 were considered as statistically significant. Results: Out of a total of 525 implanted leads and 255 implanted devices in 255 patients (mean age = 62.57 ± 13.50 years; male = 196 [76.9%]), complications leading to generator or lead replacement occurred in 32 patients (12.5%). The results revealed no significant difference between the patients with and without complications regarding gender and age (P = 0.206 and P = 0.824, respectively). Also, no significant difference was found between the two groups concerning the ejection fraction (P = 0.271). Lead fracture was the most frequent lead-related complication and was observed in 17 patients (6.6%). Besides, it was mainly observed in the RV leads. Generator-related complications leading to generator replacement were observed in 2 patients (0.7%). Conclusions: Despite considerable improvements in the ICD technology, the rate of the ICD complications leading to device replacement and surgical revision, especially those related to the leads, is still clinically important. PMID:24936484

  6. Clinical Validation of Percutaneous Cochlear Implant Surgery: Initial Report

    PubMed Central

    Labadie, Robert F.; Noble, Jack H.; Dawant, Benoit M.; Balachandran, Ramya; Majdani, Omid; Fitzpatrick, J. Michael

    2015-01-01

    Objective Percutaneous cochlear implant surgery consists of a single drill path from the lateral mastoid cortex to the cochlea via the facial recess. We sought to clinically validate this technique in patients undergoing traditional cochlear implant surgery. Study Design Prospective clinical trial. Methods After institutional regulatory board approved protocols, five ears were studied via the following steps. 1) In the clinic under local anesthesia, bone-implanted anchors were placed surrounding each mastoid. 2) Temporal-bone computed tomography (CT) scans were obtained. 3) On the CT scans, paths were planned from the lateral mastoid cortex, through the facial recess, to the basal turn of the cochlea both “manually” and “automatically” using computer software. 4) Customized microstereotactic frames were rapid-prototyped to serve as drill guides constraining the drill to follow the appropriate path. 5) During cochlear implant surgery, after drilling of the facial recess, drill guides were mounted on the bone-implanted anchors. 6) Accuracy of paths was assessed via intraoperative photodocumentation. Results All surgical paths successfully traversed the facial recess and hit the basal turn of the cochlea. Distance in millimeters (average SD) from the midpoint of the drill to the facial nerve was 1.18 ± 0.68 for the “manual” path and 1.24 ± 0.44 mm for the “automatic” path and for the chorda tympani 0.986 ± 0.48 for the “manual” path and 1.22 ± 0.62 for the “automatic” path. Conclusions Percutaneous cochlear implant access using customized drill guides based on preoperative CT scans and image-guided surgery technology can be safely accomplished. PMID:18401279

  7. Carbon Fiber Biocompatibility for Implants

    PubMed Central

    Petersen, Richard

    2016-01-01

    Carbon fibers have multiple potential advantages in developing high-strength biomaterials with a density close to bone for better stress transfer and electrical properties that enhance tissue formation. As a breakthrough example in biomaterials, a 1.5 mm diameter bisphenol-epoxy/carbon-fiber-reinforced composite rod was compared for two weeks in a rat tibia model with a similar 1.5 mm diameter titanium-6-4 alloy screw manufactured to retain bone implants. Results showed that carbon-fiber-reinforced composite stimulated osseointegration inside the tibia bone marrow measured as percent bone area (PBA) to a great extent when compared to the titanium-6-4 alloy at statistically significant levels. PBA increased significantly with the carbon-fiber composite over the titanium-6-4 alloy for distances from the implant surfaces of 0.1 mm at 77.7% vs. 19.3% (p < 10−8) and 0.8 mm at 41.6% vs. 19.5% (p < 10−4), respectively. The review focuses on carbon fiber properties that increased PBA for enhanced implant osseointegration. Carbon fibers acting as polymer coated electrically conducting micro-biocircuits appear to provide a biocompatible semi-antioxidant property to remove damaging electron free radicals from the surrounding implant surface. Further, carbon fibers by removing excess electrons produced from the cellular mitochondrial electron transport chain during periods of hypoxia perhaps stimulate bone cell recruitment by free-radical chemotactic influences. In addition, well-studied bioorganic cell actin carbon fiber growth would appear to interface in close contact with the carbon-fiber-reinforced composite implant. Resulting subsequent actin carbon fiber/implant carbon fiber contacts then could help in discharging the electron biological overloads through electrochemical gradients to lower negative charges and lower concentration. PMID:26966555

  8. Behavior of AISI SAE 1020 Steel Implanted by Titanium and Exposed to Bacteria Sulphate Deoxidizer

    NASA Astrophysics Data System (ADS)

    Niño, Ely Dannier V.; Garnica, Hernán; Dugar-Zhabon, Veleriy; Castillo, Genis

    2014-05-01

    A hybrid technology to treat solid surfaces with the pulse high voltage and electric arc discharges of low pressure with a three-dimensional ion implantation technique (3DII) is applied. This technology is used to protect AISI SAE 1020 steel against a microbiological corrosion. The titanium ion implanted steel samples (coupons) are subjected to a medium of bacteria sulphate deoxidizer (BSD) which are very typical of the hydrocarbon industry and are potentially harmful for structures when are in contact with petroleum and some of its derivatives. The used technology aims to find an effective hybrid procedure to minimize the harmful effects of bacteria on AISI SAE 1020 steel. The hybrid technology efficiency of superficial titanium implantation is estimated through the measurements of the point corrosion characteristics obtained after testing both the treated and non-treated coupons. The three-dimensional surface structures of the samples are reconstructed with help of a confocal microscope.

  9. [Needle implantations--clinical report].

    PubMed

    Esswein, W

    1977-04-01

    In the last four years 27 patients with edentulous lower jaw were treated with implantation of rows of tantalum needles; 25 of them were followed up clinically and radiologically. After an average of two years and seven months where the success rate was found to be 72%. Reasons for failure were thought to be mistakes in operative technique, insufficient oral hygiene of the patients and less than optimal aftercare. These needle implants have proved their value also in cases with marked atrophy of the lower jaw where other prosthetic-surgical methods aimed at improving the prosthesis site have failed.

  10. A Percutaneously Implantable Fetal Pacemaker

    PubMed Central

    Zhou, Li; Vest, Adriana N.; Chmait, Ramen H.; Bar-Cohen, Yaniv; Pruetz, Jay; Silka, Michael; Zheng, Kaihui; Peck, Ray; Loeb, Gerald E.

    2015-01-01

    A miniaturized, self-contained pacemaker that could be implanted with a minimally invasive technique would dramatically improve the survival rate for fetuses that develop hydrops fetalis as a result of congenital heart block. We are currently validating a device that we developed to address this bradyarrhythmia. Preclinical studies in a fetal sheep model are underway to demonstrate that the device can be implanted via a minimally invasive approach, can mechanically withstand the harsh bodily environment, can induce effective contractions of the heart muscle with an adequate safety factor, and can successfully operate for the required device lifetime of three months using the previously-developed closed loop transcutaneous recharging system. PMID:25570982

  11. FDA Approves Eye Implant for Aging Boomers

    MedlinePlus

    ... fullstory_159648.html FDA Approves Eye Implant for Aging Boomers Tiny lens reshapes cornea to improve focus ... 2016 (HealthDay News) -- An implant that helps the aging eye focus on small print and nearby objects ...

  12. Elderly Benefit from Using Implantable Defibrillators

    MedlinePlus

    ... org Learn More Elderly benefit from using implantable defibrillators June 17, 2013 Categories: Heart News Study Highlights: Older people may benefit from implantable cardioverter defibrillators (ICDs) as much as younger people. Overall health, ...

  13. How Does an Implantable Cardioverter Defibrillator Work?

    MedlinePlus

    ... on Twitter. How Does an Implantable Cardioverter Defibrillator Work? An implantable cardioverter defibrillator (ICD) has wires with ... tune the programming of your ICD so it works better to correct irregular heartbeats. The type of ...

  14. Physiological and molecular determinants of embryo implantation

    PubMed Central

    Zhang, Shuang; Lin, Haiyan; Kong, Shuangbo; Wang, Shumin; Wang, Hongmei; Wang, Haibin; Armant, D. Randall

    2014-01-01

    Embryo implantation involves the intimate interaction between an implantation-competent blastocyst and a receptive uterus, which occurs in a limited time period known as the window of implantation. Emerging evidence shows that defects originating during embryo implantation induce ripple effects with adverse consequences on later gestation events, highlighting the significance of this event for pregnancy success. Although a multitude of cellular events and molecular pathways involved in embryo-uterine crosstalk during implantation have been identified through gene expression studies and genetically engineered mouse models, a comprehensive understanding of the nature of embryo implantation is still missing. This review focuses on recent progress with particular attention to physiological and molecular determinants of blastocyst activation, uterine receptivity, blastocyst attachment and uterine decidualization. A better understanding of underlying mechanisms governing embryo implantation should generate new strategies to rectify implantation failure and improve pregnancy rates in women. PMID:23290997

  15. Implantable Cardiac Defibrillator Lead Failure and Management.

    PubMed

    Swerdlow, Charles D; Kalahasty, Gautham; Ellenbogen, Kenneth A

    2016-03-22

    The implantable-cardioverter defibrillator (ICD) lead is the most vulnerable component of the ICD system. Despite advanced engineering design, sophisticated manufacturing techniques, and extensive bench, pre-clinical, and clinical testing, lead failure (LF) remains the Achilles' heel of the ICD system. ICD LF has a broad range of adverse outcomes, ranging from intermittent inappropriate pacing to proarrhythmia leading to patient mortality. ICD LF is often considered in the context of design or construction defects, but is more appropriately considered in the context of the finite service life of a mechanical component placed in chemically stressful environment and subjected to continuous mechanical stresses. This clinical review summarizes LF mechanisms, assessment, and differential diagnosis of LF, including lead diagnostics, recent prominent lead recalls, and management of LF and functioning, but recalled leads. Despite recent advances in lead technology, physicians will likely continue to need to understand how to manage patients with transvenous ICD leads. PMID:26988958

  16. Hearing Restoration with Auditory Brainstem Implant

    PubMed Central

    NAKATOMI, Hirofumi; MIYAWAKI, Satoru; KIN, Taichi; SAITO, Nobuhito

    2016-01-01

    Auditory brainstem implant (ABI) technology attempts to restore hearing in deaf patients caused by bilateral cochlear nerve injury through the direct stimulation of the brainstem, but many aspects of the related mechanisms remain unknown. The unresolved issues can be grouped into three topics: which patients are the best candidates; which type of electrode should be used; and how to improve restored hearing. We evaluated our experience with 11 cases of ABI placement. We found that if at least seven of eleven electrodes of the MED-EL ABI are effectively placed in a patient with no deformation of the fourth ventricle, open set sentence recognition of approximately 20% and closed set word recognition of approximately 65% can be achieved only with the ABI. Appropriate selection of patients for ABI placement can lead to good outcomes. Further investigation is required regarding patient selection criteria and methods of surgery for effective ABI placement. PMID:27464470

  17. Implantable Cardiac Defibrillator Lead Failure and Management.

    PubMed

    Swerdlow, Charles D; Kalahasty, Gautham; Ellenbogen, Kenneth A

    2016-03-22

    The implantable-cardioverter defibrillator (ICD) lead is the most vulnerable component of the ICD system. Despite advanced engineering design, sophisticated manufacturing techniques, and extensive bench, pre-clinical, and clinical testing, lead failure (LF) remains the Achilles' heel of the ICD system. ICD LF has a broad range of adverse outcomes, ranging from intermittent inappropriate pacing to proarrhythmia leading to patient mortality. ICD LF is often considered in the context of design or construction defects, but is more appropriately considered in the context of the finite service life of a mechanical component placed in chemically stressful environment and subjected to continuous mechanical stresses. This clinical review summarizes LF mechanisms, assessment, and differential diagnosis of LF, including lead diagnostics, recent prominent lead recalls, and management of LF and functioning, but recalled leads. Despite recent advances in lead technology, physicians will likely continue to need to understand how to manage patients with transvenous ICD leads.

  18. Rhenium ion beam for implantation into semiconductors

    SciTech Connect

    Kulevoy, T. V.; Seleznev, D. N.; Alyoshin, M. E.; Kraevsky, S. V.; Yakushin, P. E.; Khoroshilov, V. V.; Gerasimenko, N. N.; Smirnov, D. I.; Fedorov, P. A.; Temirov, A. A.

    2012-02-15

    At the ion source test bench in Institute for Theoretical and Experimental Physics the program of ion source development for semiconductor industry is in progress. In framework of the program the Metal Vapor Vacuum Arc ion source for germanium and rhenium ion beam generation was developed and investigated. It was shown that at special conditions of ion beam implantation it is possible to fabricate not only homogenous layers of rhenium silicides solid solutions but also clusters of this compound with properties of quantum dots. At the present moment the compound is very interesting for semiconductor industry, especially for nanoelectronics and nanophotonics, but there is no very developed technology for production of nanostructures (for example quantum sized structures) with required parameters. The results of materials synthesis and exploration are presented.

  19. Implants and Ethnocide: Learning from the Cochlear Implant Controversy

    ERIC Educational Resources Information Center

    Sparrow, Robert

    2010-01-01

    This paper uses the fictional case of the "Babel fish" to explore and illustrate the issues involved in the controversy about the use of cochlear implants in prelinguistically deaf children. Analysis of this controversy suggests that the development of genetic tests for deafness poses a serious threat to the continued flourishing of Deaf culture.…

  20. The single-piece milled titanium implant bridge.

    PubMed

    Parel, Stephen M

    2003-02-01

    This new implant technology is part of the Procera product line (Nobel Biocare), and is available through a growing network of dental laboratories. It offers the possibility of a consistently excellent passive fit compared with conventional casting techniques, and essentially eliminates the labor intensive process of sectioning and soldering sometimes associated with gold alloy castings. Eliminating the distortion commonly associated with multiple firings of long-span ceramic restorations is also a significant benefit. PMID:12680267

  1. Bulk Metallic Glasses for Implantable Medical Devices and Surgical Tools.

    PubMed

    Meagher, Philip; O'Cearbhaill, Eoin D; Byrne, James H; Browne, David J

    2016-07-01

    With increasing knowledge of the materials science of bulk metallic glasses (BMGs) and improvements in their properties and processing, they have started to become candidate materials for biomedical devices. A dichotomy in the types of medical applications has also emerged, in which some families of BMGs are being developed for permanent devices whilst another family - of Mg-based alloys - is showing promise in bioabsorbable implants. The current status of these metallurgical and technological developments is summarized.

  2. Environmental standards for intraocular lens implantation.

    PubMed

    Crawford, B A; Kaufman, D V

    1984-02-01

    Successful implantation of prosthetic devices depends upon their freedom from postoperative inflammation and infection. Techniques and lessons learned in orthopaedic and other implant surgery should be applied to intraocular lens implantation. The avoidance of contamination by particles and micro-organisms is one essential principle of the surgical procedure. Practical steps are described to reduce both types of contamination. These measures taken together are recommended for adoption as a standard of environmental safety for lens implantation.

  3. Detailed spectral analysis of decellularized skin implants

    NASA Astrophysics Data System (ADS)

    Timchenko, E. V.; Timchenko, P. E.; Volova, L. T.; Dolgushkin, D. A.; Shalkovsky, P. Y.; Pershutkina, S. V.

    2016-08-01

    The resutls of detailed analysis of donor skin implants using Raman spectroscopy method are presented. Fourier-deconvolution method was used to separate overlapping spectrum lines and to improve its informativeness. Based on the processed spectra were introduced coefficients that represent changes in relative concentration of implant components, which determines the quality of implants. It was established that Raman spectroscopy method can be used in assessment of skin implants.

  4. Augmentation mammaplasty using implants: a review.

    PubMed

    Takayanagi, Susumu

    2012-09-01

    One of the techniques for augmentation mammaplasty is the procedure using implants. Even though this technique has been used for many years, there are still several controversial issues to be discussed and overcome for patient safety. In this review article, capsular contracture, leak or rupture of the implants, possible systemic disease, relation with breast cancer, and recent problems with Poly Implant Prothese implants are described and discussed. PMID:23094237

  5. Augmentation Mammaplasty Using Implants: A Review

    PubMed Central

    2012-01-01

    One of the techniques for augmentation mammaplasty is the procedure using implants. Even though this technique has been used for many years, there are still several controversial issues to be discussed and overcome for patient safety. In this review article, capsular contracture, leak or rupture of the implants, possible systemic disease, relation with breast cancer, and recent problems with Poly Implant Prothese implants are described and discussed. PMID:23094237

  6. Dental implants in the older adult.

    PubMed

    Jones, John D; Partida, M Norma; Turkyilmaz, Ilser

    2012-01-01

    A need for dental implant treatment in the older population is recognized considering the prevalence of partial and complete edentulism and the positive predictability of implant therapy. Even with a number of barriers to overcome for the older adult seeking implant care, dental implants provide stabilizing support for removable dental appliances and have been shown to be successful in that population. In this paper, we describe quality of life, systemic, surgical, and prosthodontic considerations of this prosthetic treatment along with maintenance challenges.

  7. Analytical investigation of the hygrothermal effects and parametric study of the Edge Crack Torsion (ECT) mode 3 test lay-ups

    NASA Technical Reports Server (NTRS)

    Li, Jian; Obrien, T. Kevin

    1995-01-01

    A shear deformation theory including residual thermal and moisture effects is developed for the analysis of either symmetric or unsymmetric laminates with mid-plane edge delamination under torsion loading. The theory is based on an assumed displacement field which includes shear deformation. The governing equations and boundary conditions are obtained from the principle of virtual work. The analysis of the (90/(+/- 45)(n)/(-/+ 45)(n)/90)(s) ECT mode 3 test lay-up indicates that there are no hygrothermal effects on the mode 3 strain energy release rate because the laminate, and both sublaminates above and below the delamination, are symmetric lay-ups. A further parametric study reveals that some other lay-ups can have negligible hygrothermal effects even when the sublaminates above and below the delamination are not symmetric about their own mid-planes. However, these lay-ups may suffer from distortion after the curing process. Another Interesting set of lay-ups investigated is a class of antisymmetric laminates with (+/-(theta/(theta -90)(2)/theta))(n) lay-ups. It is observed that when n takes on even numbers (2 and 4), both hygrothermal and mode 1 effects can be neglected. From this point of view, these lay-ups provide a way to determine the mode 3 toughness between two dissimilar layers. However, when n takes on odd numbers (1 and 3), both hygrothermal and mode 1 effects may be strong in these lay-ups. In particular, when theta equals 45 deg, the lay-ups are free from both hygrothermal and mode 1 effects irrespective of n.

  8. Biomedical Impact in Implantable Devices-The Transcatheter Aortic Valve as an example

    NASA Astrophysics Data System (ADS)

    Anastasiou, Alexandros; Saatsakis, George

    2015-09-01

    Objective: To update of the scientific community about the biomedical engineering involvement in the implantable devices chain. Moreover the transcatheter Aortic Valve (TAV) replacement, in the field of cardiac surgery, will be analyzed as an example of contemporary implantable technology. Methods: A detailed literature review regarding biomedical engineers participating in the implantable medical product chain, starting from the design of the product till the final implantation technique. Results: The scientific role of biomedical engineers has clearly been established. Certain parts of the product chain are implemented almost exclusively by experienced biomedical engineers such as the transcatheter aortic valve device. The successful professional should have a multidisciplinary knowledge, including medicine, in order to pursue the challenges for such intuitive technology. This clearly indicates that biomedical engineers are among the most appropriate scientists to accomplish such tasks. Conclusions: The biomedical engineering involvement in medical implantable devices has been widely accepted by the scientific community, worldwide. Its important contribution, starting from the design and extended to the development, clinical trials, scientific support, education of other scientists (surgeons, cardiologists, technicians etc.), and even to sales, makes biomedical engineers a valuable player in the scientific arena. Notably, the sector of implantable devices is constantly raising, as emerging technologies continuously set up new targets.

  9. Combined Subpectoral Implantation of Implantable Cardioverter-Defibrillator and Augmentation Mammoplasty in a Young Female Patient

    PubMed Central

    Kim, Dong-Jun; Park, Je Wook; Youn, Jong-Chan; Lee, Dong Won; Koo, Bon-Nyeo; Lee, Moon-Hyoung

    2016-01-01

    Subcutaneous implantation of a cardiac implantable electronic device is the standard method. Occasionally, subpectoral cardiac implantable electronic device (CIED) implantation via axillary incisions is performed in young female patients for cosmetic purposes. Because subpectoral CIED implantation and augmentation mammoplasty involve the same layer, it is feasible to perform both procedures simultaneously. We report a case of combined subpectoral implantation of an implantable cardioverter-defibrillator and augmentation mammoplasty via the axillary approach in a young female patient with dilated cardiomyopathy and small breasts. PMID:27721868

  10. Myths about Cochlear Implants: A Family Perspective.

    ERIC Educational Resources Information Center

    Luetke-Stahlman, B.

    1994-01-01

    A parent of two young children who received cochlear implant surgery addresses common myths about this procedure including "deaf people don't support the use of cochlear implants,""if you choose cochlear implant surgery, you are choosing the hearing world,""hearing parents are not qualified to decide," and "the deaf child him/herself should…

  11. An Uncommon Presentation of Breast Implant Rupture

    PubMed Central

    Watson, David I.; Dean, Nicola R.

    2016-01-01

    Summary: Late periprosthetic seroma has lately been concerning for breast implant-associated anaplastic large cell lymphoma. The authors present an uncommon presentation of breast implant rupture with a seroma and skin rash forming 2 years after insertion of the implant. PMID:27579243

  12. The hydroxyapatite orbital implant: a prospective study.

    PubMed

    Ashworth, J L; Rhatigan, M; Sampath, R; Brammar, R; Sunderland, S; Leatherbarrow, B

    1996-01-01

    The hydroxyapatite orbital implant was first released for use as an orbital implant in humans in August 1989. It has been shown to be well tolerated, providing good motility of the artificial eye with a low complication rate when used as a primary implant. This prospective study evaluated the hydroxyapatite orbital implant used as both a primary and a secondary implant. Sixty patients were implanted between October 1992 and November 1994, 28 being implanted as a primary procedure at the time of enucleation or evisceration, and 32 as a secondary procedure. Seven patients underwent second-stage drilling and pegging of the implant. The mean follow-up time was 13 months (range 2-26 months). A standardised operative and post-operative protocol was followed. The patients were evaluated post-operatively for the amount of enophthalmos, degree of upper lid sulcus deformity, motility of the prosthesis, location of the implant in the socket, socket status and the presence or absence of discharge, position of the drill hole and coverage of the implant. Complications and their management were documented. Both patient and surgeon made a subjective assessment of cosmesis and the patient's satisfaction with the overall result was noted. The results of this study show the hydroxyapatite orbital implant to provide excellent motility of the artificial eye and good cosmesis with a low rate of complications when used both as a primary and as a secondary implant.

  13. Design optimization of functionally graded dental implant.

    PubMed

    Hedia, H S; Mahmoud, Nemat-Alla

    2004-01-01

    The continuous increase of man's life span, and the growing confidence in using artificial materials inside the human body necessities introducing more effective prosthesis and implant materials. However, no artificial implant has biomechanical properties equivalent to the original tissue. Recently, titanium and bioceramic materials, such as hydroxyapatite are extensively used as fabrication materials for dental implant due to their high compatibility with hard tissue and living bone. Titanium has reasonable stiffness and strength while hydroxyapatite has low stiffness, low strength and high ability to reach full integration with living bone. In order to obtain good dental implantation of the biomaterial; full integration of the implant with living bone should be satisfied. Minimum stresses in the implant and the bone must be achieved to increase the life of the implant and prevent bone resorption. Therefore, the aim of the current investigation is to design an implant made from functionally graded material (FGM) to achieve the above advantages. The finite element method and optimization technique are used to reach the required implant design. The optimal materials of the FGM dental implant are found to be hydroxyapatite/titanium. The investigations have shown that the maximum stress in the bone for the hydroxyapatite/titanium FGM implant has been reduced by about 22% and 28% compared to currently used titanium and stainless steel dental implants, respectively.

  14. Rescuing failed oral implants via Wnt activation

    PubMed Central

    Yin, Xing; Li, Jingtao; Chen, Tao; Mouraret, Sylvain; Dhamdhere, Girija; Brunski, John B.; Zou, Shujuan; Helms, Jill A.

    2016-01-01

    Aim Implant osseointegration is not always guaranteed and once fibrous encapsulation occurs clinicians have few options other than implant removal. Our goal was to test whether a WNT protein therapeutic could rescue such failed implants. Material and Methods Titanium implants were placed in over-sized murine oral osteotomies. A lack of primary stability was verified by mechanical testing. Interfacial strains were estimated by finite element modelling and histology coupled with histomorphometry confirmed the lack of peri-implant bone. After fibrous encapsulation was established peri-implant injections of a liposomal formulation of WNT3A protein (L-WNT3A) or liposomal PBS (L-PBS) were then initiated. Quantitative assays were employed to analyse the effects of L-WNT3A treatment. Results Implants in gap-type interfaces exhibited high interfacial strains and no primary stability. After verification of implant failure, L-WNT3A or L-PBS injections were initiated. L-WNT3A induced a rapid, significant increase in Wnt responsiveness in the peri-implant environment, cell proliferation and osteogenic protein expression. The amount of peri-implant bone and bone in contact with the implant were significantly higher in L-WNT3A cases. Conclusions These data demonstrate L-WNT3A can induce peri-implant bone formation even in cases where fibrous encapsulation predominates. PMID:26718012

  15. An Uncommon Presentation of Breast Implant Rupture.

    PubMed

    Koh, Eugene; Watson, David I; Dean, Nicola R

    2016-05-01

    Late periprosthetic seroma has lately been concerning for breast implant-associated anaplastic large cell lymphoma. The authors present an uncommon presentation of breast implant rupture with a seroma and skin rash forming 2 years after insertion of the implant. PMID:27579243

  16. Cortical Plasticity after Cochlear Implantation

    PubMed Central

    Petersen, B.; Gjedde, A.; Wallentin, M.; Vuust, P.

    2013-01-01

    The most dramatic progress in the restoration of hearing takes place in the first months after cochlear implantation. To map the brain activity underlying this process, we used positron emission tomography at three time points: within 14 days, three months, and six months after switch-on. Fifteen recently implanted adult implant recipients listened to running speech or speech-like noise in four sequential PET sessions at each milestone. CI listeners with postlingual hearing loss showed differential activation of left superior temporal gyrus during speech and speech-like stimuli, unlike CI listeners with prelingual hearing loss. Furthermore, Broca's area was activated as an effect of time, but only in CI listeners with postlingual hearing loss. The study demonstrates that adaptation to the cochlear implant is highly related to the history of hearing loss. Speech processing in patients whose hearing loss occurred after the acquisition of language involves brain areas associated with speech comprehension, which is not the case for patients whose hearing loss occurred before the acquisition of language. Finally, the findings confirm the key role of Broca's area in restoration of speech perception, but only in individuals in whom Broca's area has been active prior to the loss of hearing. PMID:24377050

  17. Cochlear implant optimized noise reduction.

    PubMed

    Mauger, Stefan J; Arora, Komal; Dawson, Pam W

    2012-12-01

    Noise-reduction methods have provided significant improvements in speech perception for cochlear implant recipients, where only quality improvements have been found in hearing aid recipients. Recent psychoacoustic studies have suggested changes to noise-reduction techniques specifically for cochlear implants, due to differences between hearing aid recipient and cochlear implant recipient hearing. An optimized noise-reduction method was developed with significantly increased temporal smoothing of the signal-to-noise ratio estimate and a more aggressive gain function compared to current noise-reduction methods. This optimized noise-reduction algorithm was tested with 12 cochlear implant recipients over four test sessions. Speech perception was assessed through speech in noise tests with three noise types; speech-weighted noise, 20-talker babble and 4-talker babble. A significant speech perception improvement using optimized noise reduction over standard processing was found in babble noise and speech-weighted noise and over a current noise-reduction method in speech-weighted noise. Speech perception in quiet was not degraded. Listening quality testing for noise annoyance and overall preference found significant improvements over the standard processing and over a current noise-reduction method in speech-weighted and babble noise types. This optimized method has shown significant speech perception and quality improvements compared to the standard processing and a current noise-reduction method.

  18. [Biomechanics of single dental implants].

    PubMed

    Zagorskiĭ, V A; Zagorskiĭ, V V

    2013-01-01

    Bone tissues of human skull, jawbones and hard dental tissues were formed formed by the influence of chewing loads which are functional irritants used for maintaining their physical qualities. Knowledge of tensions and deformations in bony structures allows to increase their joint work with dental implants installed.

  19. Cortical plasticity after cochlear implantation.

    PubMed

    Petersen, B; Gjedde, A; Wallentin, M; Vuust, P

    2013-01-01

    The most dramatic progress in the restoration of hearing takes place in the first months after cochlear implantation. To map the brain activity underlying this process, we used positron emission tomography at three time points: within 14 days, three months, and six months after switch-on. Fifteen recently implanted adult implant recipients listened to running speech or speech-like noise in four sequential PET sessions at each milestone. CI listeners with postlingual hearing loss showed differential activation of left superior temporal gyrus during speech and speech-like stimuli, unlike CI listeners with prelingual hearing loss. Furthermore, Broca's area was activated as an effect of time, but only in CI listeners with postlingual hearing loss. The study demonstrates that adaptation to the cochlear implant is highly related to the history of hearing loss. Speech processing in patients whose hearing loss occurred after the acquisition of language involves brain areas associated with speech comprehension, which is not the case for patients whose hearing loss occurred before the acquisition of language. Finally, the findings confirm the key role of Broca's area in restoration of speech perception, but only in individuals in whom Broca's area has been active prior to the loss of hearing. PMID:24377050

  20. Contamination Control in Ion Implantation

    SciTech Connect

    Eddy, R.; Doi, D.; Santos, I.; Wriggins, W.

    2011-01-07

    The investigation and elimination or control of metallic contamination in ion implanters has been a leading, continuous effort at implanter OEMs and in fabs/IDMs alike. Much of the efforts have been in the area of control of sputtering through material and geometry changes in apertures, beamline and target chamber components. In this paper, we will focus on an area that has not, heretofore, been fully investigated or controlled. This is the area of lubricants and internal and external support material such as selected cleaning media. Some of these materials are designated for internal use (beamline/vacuum) only while others are for internal and/or external use. Many applications for selected greases, for example, are designated for or are used for platens, implant disks/wheels and for wafer handling components. We will present data from popular lubricants (to be unnamed) used worldwide in ion implanters. This paper will review elements of concern in many lubricants that should be tracked and monitored by all fabs.Proper understanding of the characteristics, risks and the control of these potential contaminants can provide for rapid return to full process capability following major PMs or parts changes. Using VPD-ICPMS, Glow Discharge Mass Spectrometry and Ion Chromatography (IC) data, we will review the typical cleaning results and correlation to ''on wafer'' contamination by elements of concern--and by some elements that are otherwise barred from the fab.

  1. Immediate loading of dental implants.

    PubMed

    Henry, P J; Liddelow, G J

    2008-06-01

    The purpose of this review is to explore the concept of immediate loading as it pertains to dental implants and the indications for clinical practice. The definition of immediate loading will be considered together with a review of the relevant literature in an attempt to provide evidence-based guidelines for successful implementation into practice. A search of electronic databases including Medline, PubMed and the Cochrane Database of Systematic Reviews was undertaken using the terms "immediate loading'', "dental implants'', "immediate function'', "early loading'', "oral implants'', "immediate restoration'' and "systematic review''. This was supplemented by handsearching in peer-reviewed journals and cross-referenced with the articles accessed. Emphasis was given to systematic reviews and controlled clinical trials. A definition of immediate loading was suggested pertinent to the realities of logistics in clinical practice with respect to application and time frame. The literature was evaluated and shown to be limited with significant shortcomings. Guidelines and recommendations for clinical protocols were suggested and illustrated by examples of case types with a minimum of 1-3 years follow-up. A list of additional references for further reading was provided. Within the limitations of this review, there is evidence to suggest that immediate loading protocols have demonstrated high implant survival rates and may be cautiously recommended for certain clinical situations. However, more high level evidence studies, preferably randomized controlled trials (RCTs), over a long time frame are required to show a clear benefit over more conventional loading protocols.

  2. Sterility of packaged implant components.

    PubMed

    Worthington, Philip

    2005-01-01

    Several implant components in their original glass vial and peel-back packages were subjected to sterility testing to determine whether the contents remained sterile after the expiration date marked on the package had passed. The results from a university microbiology laboratory showed that the contents remained sterile for 6 to 11 years after the expiration dates. PMID:15973959

  3. Cortical plasticity after cochlear implantation.

    PubMed

    Petersen, B; Gjedde, A; Wallentin, M; Vuust, P

    2013-01-01

    The most dramatic progress in the restoration of hearing takes place in the first months after cochlear implantation. To map the brain activity underlying this process, we used positron emission tomography at three time points: within 14 days, three months, and six months after switch-on. Fifteen recently implanted adult implant recipients listened to running speech or speech-like noise in four sequential PET sessions at each milestone. CI listeners with postlingual hearing loss showed differential activation of left superior temporal gyrus during speech and speech-like stimuli, unlike CI listeners with prelingual hearing loss. Furthermore, Broca's area was activated as an effect of time, but only in CI listeners with postlingual hearing loss. The study demonstrates that adaptation to the cochlear implant is highly related to the history of hearing loss. Speech processing in patients whose hearing loss occurred after the acquisition of language involves brain areas associated with speech comprehension, which is not the case for patients whose hearing loss occurred before the acquisition of language. Finally, the findings confirm the key role of Broca's area in restoration of speech perception, but only in individuals in whom Broca's area has been active prior to the loss of hearing.

  4. Radial 32P ion implantation using a coaxial plasma reactor: Activity imaging and numerical integration

    NASA Astrophysics Data System (ADS)

    Fortin, M. A.; Dufresne, V.; Paynter, R.; Sarkissian, A.; Stansfield, B.

    2004-12-01

    Beta-emitting biomedical implants are currently employed in angioplasty, in the treatment of certain types of cancers, and in the embolization of aneurysms with platinum coils. Radioisotopes such as 32P can be implanted using plasma-based ion implantation (PBII). In this article, we describe a reactor that was developed to implant radioisotopes into cylindrical metallic objects. The plasma first ionizes radioisotopes sputtered from a target, and then acts as the source of particles to be implanted into the biased biomedical device. The plasma therefore plays a major role in the ionization/implantation process. Following a sequence of implantation tests, the liners protecting the interior walls of the reactor were changed and the radioactivity on them measured. This study demonstrates that the radioactive deposits on these protective liners, adequately imaged by radiography, can indicate the distribution of the radioisotopes that are not implanted. The resulting maps give unique information about the activity distribution, which is influenced by the sputtering of the 32P-containing fragments, their ionization in the plasma, and also by the subsequent ion transport mechanisms. Such information can be interpreted and used to significantly improve the efficiency of the implantation procedure. Using a surface barrier detector, a comparative study established a relationship between the gray scale of radiographs of the liners, and activity measurements. An integration process allows the quantification of the activities on the walls and components of the reactor. Finally, the resulting integral of the 32P activity is correlated to the sum of the radioactivity amounts that were sputtered from radioactive targets inside the implanter before the dismantling procedure. This balance addresses the issue of security regarding PBII technology and confirms the confinement of the radioactivity inside the chamber.

  5. Tunnel oxide passivated contacts formed by ion implantation for applications in silicon solar cells

    NASA Astrophysics Data System (ADS)

    Reichel, Christian; Feldmann, Frank; Müller, Ralph; Reedy, Robert C.; Lee, Benjamin G.; Young, David L.; Stradins, Paul; Hermle, Martin; Glunz, Stefan W.

    2015-11-01

    Passivated contacts (poly-Si/SiOx/c-Si) doped by shallow ion implantation are an appealing technology for high efficiency silicon solar cells, especially for interdigitated back contact (IBC) solar cells where a masked ion implantation facilitates their fabrication. This paper presents a study on tunnel oxide passivated contacts formed by low-energy ion implantation into amorphous silicon (a-Si) layers and examines the influence of the ion species (P, B, or BF2), the ion implantation dose (5 × 1014 cm-2 to 1 × 1016 cm-2), and the subsequent high-temperature anneal (800 °C or 900 °C) on the passivation quality and junction characteristics using double-sided contacted silicon solar cells. Excellent passivation quality is achieved for n-type passivated contacts by P implantations into either intrinsic (undoped) or in-situ B-doped a-Si layers with implied open-circuit voltages (iVoc) of 725 and 720 mV, respectively. For p-type passivated contacts, BF2 implantations into intrinsic a-Si yield well passivated contacts and allow for iVoc of 690 mV, whereas implanted B gives poor passivation with iVoc of only 640 mV. While solar cells featuring in-situ B-doped selective hole contacts and selective electron contacts with P implanted into intrinsic a-Si layers achieved Voc of 690 mV and fill factor (FF) of 79.1%, selective hole contacts realized by BF2 implantation into intrinsic a-Si suffer from drastically reduced FF which is caused by a non-Ohmic Schottky contact. Finally, implanting P into in-situ B-doped a-Si layers for the purpose of overcompensation (counterdoping) allowed for solar cells with Voc of 680 mV and FF of 80.4%, providing a simplified and promising fabrication process for IBC solar cells featuring passivated contacts.

  6. Radial {sup 32}P ion implantation using a coaxial plasma reactor: Activity imaging and numerical integration

    SciTech Connect

    Fortin, M.A.; Dufresne, V.; Paynter, R.; Sarkissian, A.; Stansfield, B.

    2004-12-01

    Beta-emitting biomedical implants are currently employed in angioplasty, in the treatment of certain types of cancers, and in the embolization of aneurysms with platinum coils. Radioisotopes such as {sup 32}P can be implanted using plasma-based ion implantation (PBII). In this article, we describe a reactor that was developed to implant radioisotopes into cylindrical metallic objects. The plasma first ionizes radioisotopes sputtered from a target, and then acts as the source of particles to be implanted into the biased biomedical device. The plasma therefore plays a major role in the ionization/implantation process. Following a sequence of implantation tests, the liners protecting the interior walls of the reactor were changed and the radioactivity on them measured. This study demonstrates that the radioactive deposits on these protective liners, adequately imaged by radiography, can indicate the distribution of the radioisotopes that are not implanted. The resulting maps give unique information about the activity distribution, which is influenced by the sputtering of the {sup 32}P-containing fragments, their ionization in the plasma, and also by the subsequent ion transport mechanisms. Such information can be interpreted and used to significantly improve the efficiency of the implantation procedure. Using a surface barrier detector, a comparative study established a relationship between the gray scale of radiographs of the liners, and activity measurements. An integration process allows the quantification of the activities on the walls and components of the reactor. Finally, the resulting integral of the {sup 32}P activity is correlated to the sum of the radioactivity amounts that were sputtered from radioactive targets inside the implanter before the dismantling procedure. This balance addresses the issue of security regarding PBII technology and confirms the confinement of the radioactivity inside the chamber.

  7. Full rehabilitation with nobel clinician® and procera implant bridge®: case report

    PubMed Central

    SPINELLI, D.; OTTRIA, L.; DE VICO, G.; BOLLERO, R.; BARLATTANI, A.; BOLLERO, P.

    2013-01-01

    SUMMARY Implant surgery has been changing in different ways following improvements of computer technologies. Since its beginning, according to the original procedures of Branemårk system implants, guide-lines in implants-supported prosthetic rehabilitation have been founding on the placement of fixtures in a fairly upright position, after maxillary sinus floor elevation; while in the case of interforaminal rehabilitation, an upright distal implant may need to be placed anterior to the mental foramina without nerve damage (although the consequence would have been bilateral cantilevers to provide good chewing capacity). Some authors have proposed engaging the molar/tuberosity area: Bahat and Venturelli demonstrated these areas reliable and predictable alternative to distal cantilever prostheses or sinus elevation procedures. In recent years, the immediate loading of tilted implants with a provisional restoration has been proposed for the treatment of the atrophic maxilla. Tilted posterior implants in either arches could avoid (cantilever length) and provide to a better load distribution. Further studies have showed excellent outcomes for both tilted and axial implants; indeed this protocol allows to use longer implants, improve bone anchorage and avoid bone grafting procedures. Malò at al., in a retrospective clinical study, showed important results using two posterior tilted implants and two anterior non-tilted ones in the so-called All-on-four technique (Nobel Biocare, Göteborg, Sweden). Instead of the great loss of bone (amount and quality) in long-term edentuly the clinically documented computer-guided implantology software is able, through posterior tilted implants, to improve load distribution. Many authors have reported reduced surgical invasion (sinus grafting surgery is needless), shorter treatment time, lower cost, natural aesthetic profiles and functional bite. PMID:24175051

  8. Iodine-Supported Hip Implants: Short Term Clinical Results

    PubMed Central

    Kabata, Tamon; Maeda, Toru; Kajino, Yoshitomo; Hasegawa, Kazuhiro; Inoue, Daisuke; Yamamoto, Takashi; Takagi, Tomoharu; Ohmori, Takaaki; Tsuchiya, Hiroyuki

    2015-01-01

    We developed a new povidone iodine coating technology for titanium hip implants and performed a clinical trial to assess its usefulness in suppressing postoperative infection. Results indicate that iodine-supported titanium has favorable antibacterial activity, biocompatibility, and no cytotoxicity. Thirty joints in 28 patients were treated using iodine-supported implants. Fourteen joints were revision total hip arthroplasty (THA) after periprosthetic infection, 13 were primary THA for immunosuppressive conditions or pyogenic arthritis, and 3 were conversions from hemiarthroplasty to THA for immunosuppressive conditions. Two examinations were conducted sequentially until final follow-up: white blood cell (WBC) and C-reactive protein (CRP) were measured pre- and postoperatively and thyroid hormone levels in the blood were examined. The mean follow-up period was 33 months (14–78). There were no signs of infection in any patient at the last follow-up. WBC and CRP levels returned to normal within several weeks. No abnormalities of thyroid gland function were detected. Loosening of the implants did not occur in any patient. Excellent bone ingrowth and ongrowth were found around prostheses. No cytotoxicity or adverse effects were detected. These results suggest that iodine-supported THA implants can be highly effective in preventing and treating postoperative infections. PMID:26583103

  9. The cardiac implantable electronic device power source: evolution and revolution.

    PubMed

    Mond, Harry G; Freitag, Gary

    2014-12-01

    Although the first power source for an implantable pacemaker was a rechargeable nickel-cadmium battery, it was rapidly replaced by an unreliable short-life zinc-mercury cell. This sustained the small pacemaker industry until the early 1970s, when the lithium-iodine cell became the dominant power source for low voltage, microampere current, single- and dual-chamber pacemakers. By the early 2000s, a number of significant advances were occurring with pacemaker technology which necessitated that the power source should now provide milliampere current for data logging, telemetric communication, and programming, as well as powering more complicated pacing devices such as biventricular pacemakers, treatment or prevention of atrial tachyarrhythmias, and the integration of innovative physiologic sensors. Because the current delivery of the lithium-iodine battery was inadequate for these functions, other lithium anode chemistries that can provide medium power were introduced. These include lithium-carbon monofluoride, lithium-manganese dioxide, and lithium-silver vanadium oxide/carbon mono-fluoride hybrids. In the early 1980s, the first implantable defibrillators for high voltage therapy used a lithium-vanadium pentoxide battery. With the introduction of the implantable cardioverter defibrillator, the reliable lithium-silver vanadium oxide became the power source. More recently, because of the demands of biventricular pacing, data logging, and telemetry, lithium-manganese dioxide and the hybrid lithium-silver vanadium oxide/carbon mono-fluoride laminate have also been used. Today all cardiac implantable electronic devices are powered by lithium anode batteries.

  10. Template-guided implantation of the Bonebridge: clinical experience.

    PubMed

    Matsumoto, Nozomu; Takumi, Yutaka; Cho, Byunghyun; Mori, Kentaro; Usami, Shin-Ichi; Yamashita, Makoto; Hashizume, Makoto; Komune, Shizuo

    2015-12-01

    The surgical procedure for Bonebridge implantation cannot be done in some cases without exposing the dura mater or sigmoid sinus. Surgical simulation technology can help to identify such difficulties prior to surgery and be used to clarify the optimal location and orientation of the device to be implanted. However, there has not been a simple strategy to drill the temporal bone at exactly the same location as that simulated on the computer. Based on our previous development of the surface template-assisted marker positioning (STAMP) method for performing image-guided otologic surgery, we recently developed a noninvasive guiding method, the BB-STAMP method, for performing image-guided Bonebridge implantation. Three patients underwent Bonebridge implantation at our surgical center during the years of 2013-2014. The authors in the simulation center supported the surgery using the BB-STAMP method. The time and effort required to prepare for the surgery were evaluated. In addition, a postoperative analysis was performed to assess the accuracy of placing the device in the planned location. The BB-STAMP method enabled the surgeon to precisely replicate the computer simulation in the real patient with submillimetric accuracy without complexity. Thus, the use of experienced and elaborative simulation coupled with the creation of a tailor-made three-dimensional template (BB-STAMP) enables surgeons to perform quick, precise and safe surgical procedures at distant institutions.

  11. Effectiveness of Implant Therapy Analyzed in a Swedish Population: Prevalence of Peri-implantitis.

    PubMed

    Derks, J; Schaller, D; Håkansson, J; Wennström, J L; Tomasi, C; Berglundh, T

    2016-01-01

    Peri-implantitis is an inflammatory disease affecting soft and hard tissues surrounding dental implants. As the global number of individuals that undergo restorative therapy through dental implants increases, peri-implantitis is considered as a major and growing problem in dentistry. A randomly selected sample of 588 patients who all had received implant-supported therapy 9 y earlier was clinically and radiographically examined. Prevalence of peri-implantitis was assessed and risk indicators were identified by multilevel regression analysis. Forty-five percent of all patients presented with peri-implantitis (bleeding on probing/suppuration and bone loss >0.5 mm). Moderate/severe peri-implantitis (bleeding on probing/suppuration and bone loss >2 mm) was diagnosed in 14.5%. Patients with periodontitis and with ≥4 implants, as well as implants of certain brands and prosthetic therapy delivered by general practitioners, exhibited higher odds ratios for moderate/severe peri-implantitis. Similarly, higher odds ratios were identified for implants installed in the mandible and with crown restoration margins positioned ≤1.5 mm from the crestal bone at baseline. It is suggested that peri-implantitis is a common condition and that several patient- and implant-related factors influence the risk for moderate/severe peri-implantitis (ClinicalTrials.gov NCT01825772). PMID:26701919

  12. Analysis of implant-failure predictors in the posterior maxilla: a retrospective study of 1395 implants.

    PubMed

    Pabst, Andreas Max; Walter, Christian; Ehbauer, Sebastian; Zwiener, Isabella; Ziebart, Thomas; Al-Nawas, Bilal; Klein, Marcus Oliver

    2015-04-01

    The aim of this study was to analyze predictors for dental implant failure in the posterior maxilla. A database was created to include patients being treated with dental implants posterior to the maxillary cuspids. Independent variables thought to be predictive of potential implant failure included (1) sinus elevation, (2) implant length, (3) implant diameter, (4) indication, (5) implant region, (6) timepoint of implant placement, (7) one-vs. two-stage augmentation, and (8) healing mode. Cox regression analysis was used to evaluate the influence of predictors 1-3 on implant failure as dependent variable. The predictors 4-9 were analyzed strictly descriptively. The final database included 592 patients with 1395 implants. The overall 1- and 5-year implant survival rates were 94.8% and 88.6%, respectively. The survival rates for sinus elevation vs. placement into native bone were 94.4% and 95.4%, respectively (p = 0.33). The survival rates for the short (<10 mm), the middle (10-13 mm) and the long implants (>13 mm) were 100%, 89% and 76.8%, respectively (middle-vs. long implants p = 0.62). The implant survival rates for the small- (<3.6 mm), the middle- (3.6-4.5 mm) and the wide diameter implants (>4.5 mm) were 92.5%, 87.9% and 89.6%, respectively (p = 0.0425). None of the parameters evaluated were identified as predictor of implant failure in the posterior maxilla.

  13. IMPORTANCE OF COCHLEAR HEALTH FOR IMPLANT FUNCTION

    PubMed Central

    Pfingst, Bryan E.; Zhou, Ning; Colesa, Deborah J.; Watts, Melissa M.; Strahl, Stefan B.; Garadat, Soha N.; Schvartz-Leyzac, Kara C.; Budenz, Cameron L.; Raphael, Yehoash; Zwolan, Teresa A.

    2014-01-01

    Amazing progress has been made in providing useful hearing to hearing-impaired individuals using cochlear implants, but challenges remain. One such challenge is understanding the effects of partial degeneration of the auditory nerve, the target of cochlear implant stimulation. Here we review studies from our human and animal laboratories aimed at characterizing the health of the implanted cochlea and the auditory nerve. We use the data on cochlear and neural health to guide rehabilitation strategies. The data also motivate the development of tissue-engineering procedures to preserve or build a healthy cochlea and improve performance obtained by cochlear implant recipients or eventually replace the need for a cochlear implant. PMID:25261772

  14. Skeletal implants in aesthetic facial surgery.

    PubMed

    Cox, A J; Wang, T D

    1999-01-01

    The features of the nose, mentum, and malar complex define a person's profile and give the essence of character to the visage. Whether profile deficiencies are due to congenital, traumatic, or aging factors, facial plastic surgeons are able to meet patients' and their own exacting demands more thoroughly with skeletal implants. Although the search for the perfect implant continues, today's armamentarium of implant materials is vast and, with appropriate selection and attention to technique, facial skeletal implants can be successful in creating change impossible to obtain with soft tissue techniques alone. This article reviews both the biomaterials used in mandibular and malar complex implants and the techniques.

  15. Surface biotechnology for refining cochlear implants.

    PubMed

    Tan, Fei; Walshe, Peter; Viani, Laura; Al-Rubeai, Mohamed

    2013-12-01

    The advent of the cochlear implant is phenomenal because it is the first surgical prosthesis that is capable of restoring one of the senses. The subsequent rapid evolution of cochlear implants through increasing complexity and functionality has been synchronized with the recent advancements in biotechnology. Surface biotechnology has refined cochlear implants by directly influencing the implant–tissue interface. Emerging surface biotechnology strategies are exemplified by nanofibrous polymeric materials, topographical surface modification, conducting polymer coatings, and neurotrophin-eluting implants. Although these novel developments have received individual attention in the recent literature, the time has come to investigate their collective applications to cochlear implants to restore lost hearing. PMID:24404581

  16. Choice of a dental implant system.

    PubMed

    Hunt, Peter R; Gartner, Judith L; Norkin, Frederic J

    2005-04-01

    Many dentists are bewildered by the intricacies and complexities of dental implants. They are constantly besieged by product advertisements and can find it difficult to choose which systems to work with. Some dentists are so intimidated by the subject that they choose to avoid getting involved with implants and instead stick to traditional tooth replacement systems. By breaking implants down into 4 main components, the body, collar, connection, and restorative post, it is easier to understand the structure and function of dental implants. Each portion should be designed to achieve certain objectives. Once these structural components are understood, it is easier to compare and contrast differing implant systems.

  17. Surface biotechnology for refining cochlear implants.

    PubMed

    Tan, Fei; Walshe, Peter; Viani, Laura; Al-Rubeai, Mohamed

    2013-12-01

    The advent of the cochlear implant is phenomenal because it is the first surgical prosthesis that is capable of restoring one of the senses. The subsequent rapid evolution of cochlear implants through increasing complexity and functionality has been synchronized with the recent advancements in biotechnology. Surface biotechnology has refined cochlear implants by directly influencing the implant–tissue interface. Emerging surface biotechnology strategies are exemplified by nanofibrous polymeric materials, topographical surface modification, conducting polymer coatings, and neurotrophin-eluting implants. Although these novel developments have received individual attention in the recent literature, the time has come to investigate their collective applications to cochlear implants to restore lost hearing.

  18. Autogenous dermis-fat "baseball" orbital implant.

    PubMed

    Bullock, J D

    1987-01-01

    A new procedure has been devised for the construction of an autogenous dermis-fat orbital implant, in which two figure-eight-shaped dermis-fat grafts are sutured together into a baseball shape. Correct implant size can be determined by preplacement of different-sized Mule spheres and testing for accurate fit. The "baseball" implant eliminates deep orbital fat which is distant from a vascular supply, and because it is covered with dermis, it maximizes graft vascularization, thus promoting survival of the implanted tissues. In eight patients, followed postoperatively for as long as 28 months, baseball implants have produced highly satisfactory results.

  19. Design and fabrication of a novel porous implant with pre-set channels based on ceramic stereolithography for vascular implantation.

    PubMed

    Bian, Weiguo; Li, Dichen; Lian, Qin; Zhang, Weijie; Zhu, Linzhong; Li, Xiang; Jin, Zhongmin

    2011-09-01

    Being a multi-etiological factors disease, osteonecrosis of the femoral head affects many young people, leading to the collapse of the femur head; eventually the hip arthroplasty is needed if not treated in time. Unfortunately, as yet, no satisfactory therapy to repair necrotic bone at an early stage is present. Novel implants with pre-set channels were designed for the treatment of early femoral head necrosis. Ceramic stereolithography was applied to fabricate the green part from β-TCP powder. Other processes, such as dehydration, rinsing, drying and sintering, were processed successively. The final ceramic part remains the same as the engineered part in both shape and internal structure. No significant deformation or crack occurred. X-ray diffraction showed that no facies changed or chemical reaction occurred during the fabrication process. The chemical composition remains the same as that of the original β-TCP powder. The compressive strength is 23.54 MPa, close to that of natural cancellous bone. Novel implants with a pre-set channel were designed and fabricated for blood vessel implantation. Bioceramic stereolithography technology based directly on the CAD model in this research shows advantages in accurate design, optimization of 3D scaffold and critical control of the fabrication process. This proposed implant shows promising clinical application in the restoration of early femoral head necrosis.

  20. Biofunctionalization of surfaces by energetic ion implantation: Review of progress on applications in implantable biomedical devices and antibody microarrays

    NASA Astrophysics Data System (ADS)

    Bilek, Marcela M. M.

    2014-08-01

    Despite major research efforts in the field of biomaterials, rejection, severe immune responses, scar tissue and poor integration continue to seriously limit the performance of today's implantable biomedical devices. Implantable biomaterials that interact with their host via an interfacial layer of active biomolecules to direct a desired cellular response to the implant would represent a major and much sought after improvement. Another, perhaps equally revolutionary, development that is on the biomedical horizon is the introduction of cost-effective microarrays for fast, highly multiplexed screening for biomarkers on cell membranes and in a variety of analyte solutions. Both of these advances will rely on effective methods of functionalizing surfaces with bioactive molecules. After a brief introduction to other methods currently available, this review will describe recently developed approaches that use energetic ions extracted from plasma to facilitate simple, one-step covalent surface immobilization of bioactive molecules. A kinetic theory model of the immobilization process by reactions with long-lived, mobile, surface-embedded radicals will be presented. The roles of surface chemistry and microstructure of the ion treated layer will be discussed. Early progress on applications of this technology to create diagnostic microarrays and to engineer bioactive surfaces for implantable biomedical devices will be reviewed.