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https://www.readbyqxmd.com/read/28325008/feasibility-of-an-ultra-low-power-digital-signal-processor-platform-as-a-basis-for-a-fully-implantable-brain-computer-interface-system
#1
Po T Wang, Keulanna Gandasetiawan, Colin M McCrimmon, Alireza Karimi-Bidhendi, Charles Y Liu, Payam Heydari, Zoran Nenadic, An H Do
A fully implantable brain-computer interface (BCI) can be a practical tool to restore independence to those affected by spinal cord injury. We envision that such a BCI system will invasively acquire brain signals (e.g. electrocorticogram) and translate them into control commands for external prostheses. The feasibility of such a system was tested by implementing its benchtop analogue, centered around a commercial, ultra-low power (ULP) digital signal processor (DSP, TMS320C5517, Texas Instruments). A suite of signal processing and BCI algorithms, including (de)multiplexing, Fast Fourier Transform, power spectral density, principal component analysis, linear discriminant analysis, Bayes rule, and finite state machine was implemented and tested in the DSP...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324965/high-dielectric-material-in-mri-numerical-assessment-of-the-reduction-of-the-induced-local-power-on-implanted-cardiac-leads
#2
Eugenio Mattei, Elena Lucano, Federica Censi, Leonardo M Angelone, Giovanni Calcagnini
High dielectric materials (HDM) have been proposed in magnetic resonance imaging (MRI) to increase the signal-to-noise ratio (SNR) of the images acquired while reducing the radiofrequency (RF) absorption in tissue. The aim of this study is to assess the potential merit of using HDM to reduce power induced at the tip of an endocardial lead in patients undergoing MRI. Numerical simulations were performed using a commercial finite-differences time-domain (FDTD) software to model the RF field generated by a birdcage body coil at 64 MHz on a human body model...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324954/hardware-friendly-seizure-detection-with-a-boosted-ensemble-of-shallow-decision-trees
#3
Mahsa Shoaran, Masoud Farivar, Azita Emami
Efficient on-chip learning is becoming an essential element of implantable biomedical devices. Despite a substantial literature on automated seizure detection algorithms, hardware-friendly implementation of such techniques is not sufficiently addressed. In this paper, we propose to employ a gradientboosted ensemble of decision trees to achieve a reasonable trade-off between detection accuracy and implementation cost. Combined with the proposed feature extraction model, we show that these classifiers quickly become competitive with more complex learning models previously proposed for hardware implementation, with only a small number of low-depth (d <; 4) "shallow" trees...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324953/electrical-resistance-increases-at-the-tissue-electrode-interface-as-an-early-response-to-nucleus-accumbens-deep-brain-stimulation
#4
Rajas P Kale, Abbas Z Kouzani, Julian Berk, Ken Walder, Michael Berk, Susannah J Tye
The therapeutic actions of deep brain stimulation are not fully understood. The early inflammatory response of electrode implantation is associated with symptom relief without electrical stimulation, but is negated by anti-inflammatory drugs. Early excitotoxic necrosis and subsequent glial scarring modulate the conductivity of the tissue-electrode interface, which can provide some detail into the inflammatory response of individual patients. The feasibility of this was demonstrated by measuring resistance values across a bipolar electrode which was unilaterally implanted into the nucleus accumbens of a rat while receiving continuous deep brain stimulation with a portable back-mounted device using clinical parameters (130Hz, 200μA, 90μs) for 3 days...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324952/the-influence-of-the-pre-stimulation-neural-state-on-the-post-stimulation-neural-dynamics-via-distributed-microstimulation-of-the-hippocampus
#5
Mark J Connolly, Robert E Gross, Babak Mahmoudi
In this study we investigated how the neural state influences how the brain responds to electrical stimulation using a 16-channel microelectrode array with 8 stimulation and recording channels implanted in the rat hippocampus. In two experiments we identified the stimulation threshold at which the brain changes to an afterdischarge state. In one experiment a range of suprathreshold stimulations were applied, and in another the stimulation was not changed. The neural state was measured by the power spectral density prior to stimulation...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324946/characterization-of-motor-cortex-activity-of-the-lower-limb-region
#6
Fadi Mikhail, Karthikeyan Balasubramanian, Matthew D Best, Kazutaka Takahashi, Nicholas G Hatsopoulos
Understanding the functional properties of the motor cortex is a key step to developing effective neuroprosthetic and computer interfaces for amputees and patients with spinal cord injury. Most efforts have been directed towards studying the upper limb region of the motor cortex. Little has been done in the way of addressing lower limb motor cortical physiology. In this study, we implanted multiple microelectrode arrays along the central sulcus in the primary motor cortex of a macaque monkey. Using intracortical microstimulation, we identified neurons that evoked leg movements, either exclusively or mostly, and we studied their firing activity during a center-out arm movement task...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324933/an-ultrasonically-powered-implantable-device-for-targeted-drug-delivery
#7
Jayant Charthad, Spyridon Baltsavias, Devleena Samanta, Ting Chia Chang, Marcus J Weber, Niloufar Hosseini-Nassab, Richard N Zare, Amin Arbabian
A wirelessly powered implantable device is proposed for fully programmable and localized drug delivery. The implant is powered using an external ultrasonic transmitter and operates at <; 5% of the FDA diagnostic ultrasound intensity limit. Drug release is achieved through electrical stimulation of drug-loaded polypyrrole nanoparticles. A design methodology for the implant electronics is presented and experimentally demonstrated to be accurate in predicting the concentration of the released drug. To the best of our knowledge, this is the first ultrasonically powered implantable device platform for targeted drug delivery using electroresponsive polymers...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28324909/an-extrapericardial-minimally-invasive-approach-for-implantable-cardioverter-defibrillator
#8
Jeko M Madjarov, Michael G Katz, Brad Poole, Svetozar Madzharov, John M Fedor, Francis Robicsek
The indications for placement of an implantable cardioverter defibrillators (ICDs) have greatly expanded over the last years. However, standard transvenous approach is not suitable for a subset of patients who cannot benefit from ICD therapy. Here, we have demonstrated the feasibility and efficacy of extrapericardial ICD placement through a minimally invasive access in intact hearts as well as in postmyocardial infarction large animal models. Based on our data, we conclude that extrapericardial ICD placement is a feasible approach that may be a valuable alternative or adjunct to current defibrillator lead systems...
March 21, 2017: Thoracic and Cardiovascular Surgeon
https://www.readbyqxmd.com/read/28324865/biomaterials-for-intervertebral-disc-regeneration-and-repair
#9
REVIEW
Robert D Bowles, Lori A Setton
The intervertebral disc contributes to motion, weight bearing, and flexibility of the spine, but is susceptible to damage and morphological changes that contribute to pathology with age and injury. Engineering strategies that rely upon synthetic materials or composite implants that do not interface with the biological components of the disc have not met with widespread use or desirable outcomes in the treatment of intervertebral disc pathology. Here we review bioengineering advances to treat disc disorders, using cell-supplemented materials, or acellular, biologically based materials, that provide opportunity for cell-material interactions and remodeling in the treatment of intervertebral disc disorders...
March 15, 2017: Biomaterials
https://www.readbyqxmd.com/read/28324816/sex-differences-and-hormonal-modulation-of-ethanol-enhanced-risk-taking-in-rats
#10
Kathryn G Wallin-Miller, Jordyn Chesley, Juliana Castrillon, Ruth I Wood
BACKGROUND: Ethanol (EtOH) intake correlates with increased risk-taking, and sex differences exist in both EtOH use and risk-taking in humans and rats. However, the interaction of sex and gonadal hormones to affect risk-taking under the influence of EtOH has not been determined. This was the focus of the current study. METHODS: Adult Long-Evans rats (n=18 males and females) were gonadectomized and received hormone replacement at physiologic levels or blank implants (n=7-9/group)...
March 7, 2017: Drug and Alcohol Dependence
https://www.readbyqxmd.com/read/28324784/an-in%C3%A2-vivo-active-1-2-5-oxadiazole-pt-ii-complex-a-promising-anticancer-agent-endowed-with-stat3-inhibitory-properties
#11
Federica Porta, Giorgio Facchetti, Nicola Ferri, Arianna Gelain, Fiorella Meneghetti, Stefania Villa, Daniela Barlocco, Daniela Masciocchi, Akira Asai, Nao Miyoshi, Silvia Marchianò, Byoung-Mog Kwon, Yena Jin, Valentina Gandin, Cristina Marzano, Isabella Rimoldi
New Pt(II) complexes (Pt-1-3) bearing 1,2,5-oxadiazole ligands (1-3) were synthesized, characterized and evaluated for their ability to disrupt STAT3 dimerization. Ligand 3·HCl showed cytotoxic effects on HCT-116 cells (IC50 = 95.2 μM) and a selective ability to interact with STAT3 (IC50 = 8.2 μM) versus STAT1 (IC50 > 30 μM). Its corresponding platinum complex Pt-3 exhibited an increased cytotoxicity (IC50 = 18.4 μM) and a stronger interaction with STAT3 (IC50 = 1.4 μM), leading to inhibition of its signaling pathway...
March 15, 2017: European Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28324618/thermogelling-chitosan-lactate-hydrogel-improves-functional-recovery-after-a-c2-spinal-cord-hemisection-in-rat
#12
Katarzyna Nawrotek, Tanguy Marqueste, Zofia Modrzejewska, Roman Zarzycki, Agnieszka Rusak, Patrick Decherchi
The present study was designed to provide an appropriate micro-environment for regenerating axotomized neurons and proliferating/migrating cells. Because of its intrinsic permissive properties, biocompatibility and biodegradability, we chose to evaluate the therapeutic effectiveness of a chitosan-based biopolymer. The biomaterial toxicity was measured through in vitro test based on fibroblast cell survival on thermogelling chitosan lactate hydrogel substrate and then polymer was implanted into a C2 hemisection of the rat spinal cord...
March 21, 2017: Journal of Biomedical Materials Research. Part A
https://www.readbyqxmd.com/read/28324328/interspinous-implants-to-treat-spinal-stenosis
#13
REVIEW
Raj J Gala, Glenn S Russo, Peter G Whang
PURPOSE OF REVIEW: Lumbar spinal stenosis has historically been treated with open decompressive surgery which is associated with significant morbidity and may give rise to various complications. Interspinous spacers (ISS) have been developed as a less invasive strategy which may serve to avoid many of these risks. The two current spacers that are FDA approved and commercially available are the Coflex and Superion devices. The goal is to review these two implants, their indications, and patient selection...
March 21, 2017: Current Reviews in Musculoskeletal Medicine
https://www.readbyqxmd.com/read/28324327/lumbar-disc-replacement-surgery-successes-and-obstacles-to-widespread-adoption
#14
REVIEW
Stephan N Salzmann, Nicolas Plais, Jennifer Shue, Federico P Girardi
PURPOSE OF REVIEW: Lumbar disc replacement has been a surgical alternative to fusion surgery for the treatment of lumbar degenerative disc disease (DDD) for many years. Despite enthusiasm after the approval of the first devices, implantation rates have remained low, especially in the USA. The goal of this review is to provide a general overview of lumbar disc replacement in order to comprehend the successes and obstacles to widespread adoption. RECENT FINDINGS: Although a large amount of evidence-based data including satisfactory long-term results is available, implantation rates in the USA have not increased in the last decade...
March 21, 2017: Current Reviews in Musculoskeletal Medicine
https://www.readbyqxmd.com/read/28324276/the-cytotoxicity-and-genotoxicity-of-particulate-and-soluble-cobalt-in-human-urothelial-cells
#15
Rachel M Speer, Therry The, Hong Xie, Louis Liou, Rosalyn M Adam, John Pierce Wise
Cobalt use is increasing particularly due to its use as one of the primary metals in cobalt-chromium-molybdenum (CoCrMo) metal-on-metal prosthetics. CoCrMo is a high-strength, wear-resistant alloy with reduced risk for prosthetic loosening and device fracture. More than 500,000 people receive hip implants each year in the USA which puts them at potential risk for exposure to metal ions and particles released by the prosthetic implants. Data show cobalt ions released from prosthetics reach the bloodstream and accumulate in the bladder...
March 21, 2017: Biological Trace Element Research
https://www.readbyqxmd.com/read/28324259/protective-effect-of-nigella-sativa-seeds-against-spermatocyte-chromosomal-aberrations-and-genotoxicity-induced-by-carbon-tetrachloride-in-mice
#16
Ashraf M Abdel-Moneim, Amina E Essawy, Sherifa S Hamed, Ashgan A Abou-Gabal, Aglal A Alzergy
Nigella sativa is a well-known dietary antioxidant and a valuable inhibitor of clastogenesis and carcinogenesis. The purpose of the present work was to investigate the effects of N. sativa seeds against chromosomal aberrations in primary spermatocytes and early embryonic lethality induced by CCl4 hepatotoxin in Swiss albino mice. One hundred male Swiss albino mice were randomly divided into five groups. Groups I, II, and III received only normal saline, olive oil, and aqueous suspension of N. sativa seeds (50 mg/kg b...
March 21, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28324215/surgical-treatment-of-osteoporotic-thoraco-lumbar-compressive-fractures-the-use-of-pedicle-screw-with-augmentation-pmma
#17
Massimo Girardo, P Cinnella, G Gargiulo, P Viglierchio, A Rava, S Aleotti
INTRODUCTION: The osteoporosis prevalence in population is age related. The aim of this single-center observational study was evaluate the middle- to long-term performance of cement (PMMA) augmented fenestrated pedicle screws in elderly patients with thoraco-lumbar compressive fractures by osteoporosis. MATERIALS AND METHODS: From 2011 to 2015 we treated 52 patients (20 males and 32 females) suffering from somatic osteoporotic fractures (T10-L2). The average age was 73...
March 21, 2017: European Spine Journal
https://www.readbyqxmd.com/read/28324184/early-outcomes-of-spinal-growth-tethering-for-idiopathic-scoliosis-with-a-novel-device-a-prospective-study-with-2-years-of-follow-up
#18
M Boudissa, A Eid, E Bourgeois, J Griffet, A Courvoisier
QUESTIONS/PURPOSES: Adolescent idiopathic scoliosis is a 3D spine deformity that worsens during the whole growth. New methods for spinal growth modulation with flexible spinal implants have been described to avoid progression of the deformity during growth spurt. The main limitations are that no specific ancillaries and devices are available, which makes the surgery technically demanding. METHODS: We have developed a new method of spinal growth tethering using minimal invasive videothoracoscopic approach...
March 21, 2017: Child's Nervous System: ChNS: Official Journal of the International Society for Pediatric Neurosurgery
https://www.readbyqxmd.com/read/28324090/association-between-direct-to-consumer-advertising-and-testosterone-testing-and-initiation-in-the-united-states-2009-2013
#19
J Bradley Layton, Yoonsang Kim, G Caleb Alexander, Sherry L Emery
Importance: Testosterone initiation increased substantially in the United States from 2000 to 2013, especially among men without clear indications. Direct-to-consumer advertising (DTCA) also increased during this time. Objective: To investigate associations between televised DTCA and testosterone testing and initiation in the United States. Design, Setting, and Population: Ecologic study conducted in designated market areas (DMAs) in the United States...
March 21, 2017: JAMA: the Journal of the American Medical Association
https://www.readbyqxmd.com/read/28324064/bmp7-induces-uterine-receptivity-and-blastocyst-attachment
#20
Diana Monsivais, Caterina Clementi, Jia Peng, Paul T Fullerton, Renata Prunskaite-Hyyryläinen, Seppo Vainio, Martin M Matzuk
In women, the window of implantation is limited to a brief two- to three- day period characterized by optimal levels of circulating ovarian hormones and a receptive endometrium. Although the window of implantation is assumed to occur 8-10 days after ovulation in women, molecular markers of endometrial receptivity are necessary to determine optimal timing prior to embryo transfer. Previous studies showed that members of the bone morphogenetic protein (BMP) family are expressed in the uterus necessary for female fertility; however, the role of BMP7 during implantation and in late gestation is not known...
January 17, 2017: Endocrinology
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