keyword
MENU ▼
Read by QxMD icon Read
search

neural implants

keyword
https://www.readbyqxmd.com/read/28719819/electrical-preconditioning-of-stem-cells-with-a-conductive-polymer-scaffold-enhances-stroke-recovery
#1
Paul M George, Tonya M Bliss, Thuy Hua, Alex Lee, Byeongtaek Oh, Alexa Levinson, Swapnil Mehta, Guohua Sun, Gary K Steinberg
Exogenous human neural progenitor cells (hNPCs) are promising stroke therapeutics, but optimal delivery conditions and exact recovery mechanisms remain elusive. To further elucidate repair processes and improve stroke outcomes, we developed an electrically conductive, polymer scaffold for hNPC delivery. Electrical stimulation of hNPCs alters their transcriptome including changes to the VEGF-A pathway and genes involved in cell survival, inflammatory response, and synaptic remodeling. In our experiments, exogenous hNPCs were electrically stimulated (electrically preconditioned) via the scaffold 1 day prior to implantation...
July 12, 2017: Biomaterials
https://www.readbyqxmd.com/read/28717877/temporal-envelope-coding-by-inferior-colliculus-neurons-with-cochlear-implant-stimulation
#2
Kenneth E Hancock, Yoojin Chung, Martin F McKinney, Bertrand Delgutte
Modulations in temporal envelopes are a ubiquitous property of natural sounds and are especially important for hearing with cochlear implants (CIs) because these devices typically discard temporal fine structure information. With few exceptions, neural temporal envelope processing has been studied in both normal hearing (NH) and CI animals using only pure sinusoidal amplitude modulation (SAM) which poorly represents the diversity of envelope shapes contained in natural sounds because it confounds repetition rate and the width of each modulation cycle...
July 17, 2017: Journal of the Association for Research in Otolaryngology: JARO
https://www.readbyqxmd.com/read/28715338/closed-loop-neurostimulators-a-survey-and-a-seizure-predicting-design-example-for-intractable-epilepsy-treatment
#3
Hossein Kassiri, Sana Tonekaboni, M Tariqus Salam, Nima Soltani, Karim Abdelhalim, Jose Luis Perez Velazquez, Roman Genov
First, existing commercially available open-loop and closed-loop implantable neurostimulators are reviewed and compared in terms of their targeted application, physical size, system-level features, and performance as a medical device. Next, signal processing algorithms as the primary strength point of the closed-loop neurostimulators are reviewed, and various design and implementation requirements and trade-offs are discussed in details along with quantitative examples. The review results in a set of guidelines for algorithm selection and evaluation...
July 17, 2017: IEEE Transactions on Biomedical Circuits and Systems
https://www.readbyqxmd.com/read/28715337/compact-energy-efficient-high-frequency-switched-capacitor-neural-stimulator-with-active-charge-balancing
#4
Wen-Yang Hsu, Alexandre Schmid
Safety and energy efficiency are two major concerns for implantable neural stimulators. This paper presents a novel high-frequency, switched capacitor (HFSC) stimulation and active charge balancing scheme, which achieves high energy efficiency and well-controlled stimulation charge in the presence of large electrode impedance variations. Furthermore, the HFSC can be implemented in a compact size without any external component to simultaneously enable multichannel stimulation by deploying multiple stimulators...
July 17, 2017: IEEE Transactions on Biomedical Circuits and Systems
https://www.readbyqxmd.com/read/28713235/connecting-the-brain-to-itself-through-an-emulation
#5
Mijail D Serruya
Pilot clinical trials of human patients implanted with devices that can chronically record and stimulate ensembles of hundreds to thousands of individual neurons offer the possibility of expanding the substrate of cognition. Parallel trains of firing rate activity can be delivered in real-time to an array of intermediate external modules that in turn can trigger parallel trains of stimulation back into the brain. These modules may be built in software, VLSI firmware, or biological tissue as in vitro culture preparations or in vivo ectopic construct organoids...
2017: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/28701540/a-novel-paraplegia-model-in-awake-behaving-macaques
#6
Max Ostrinsky Krucoff, Katie Zhuang, David B Macleod, Allen Yin, Yoon Woo Byun, Roberto Jose Manson, Dennis A Turner, Laura Oliveira, Mikhail A Lebedev
Lower limb paralysis from spinal cord injury (SCI) or neurological disease carries a poor prognosis for recovery and remains a large societal burden. Neurophysiological and neuroprosthetic research have the potential to improve quality of life for these patients; however, the lack of an ethical and sustainable non-human primate model for paraplegia hinders their advancement. Therefore, our multi-disciplinary team developed a way to induce temporary paralysis in awake behaving macaques by creating a fully implantable lumbar epidural catheter-subcutaneous port system that enables easy and reliable targeted drug delivery for sensorimotor blockade...
July 12, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28700446/pure-tone-masking-patterns-for-monopolar-and-phantom-electrical-stimulation-in-cochlear-implants
#7
Aniket A Saoji, Kanthaiah Koka, Leonid M Litvak, Charles C Finley
OBJECTIVES: Monopolar stimulation of the most apical electrode produces the lowest pitch sensation in cochlear implants clinically. A phantom electrode that uses out-of-phase electrical stimulation between the most apical and the neighboring basal electrode can produce a lower pitch sensation than that associated with the most apical electrode. However, because of the absence of contacts beyond the apical tip of the array, the ability to assess the spread of electrical excitation associated with phantom stimulation is limited in the typical cochlear implant subject with no residual hearing...
July 11, 2017: Ear and Hearing
https://www.readbyqxmd.com/read/28699322/a-respiratory-marker-derived-from-left-vagus-nerve-signals-recorded-with-implantable-cuff-electrodes
#8
Cristian Sevcencu, Thomas N Nielsen, Benedict Kjaergaard, Johannes J Struijk
OBJECTIVE: Left vagus nerve (LVN) stimulation (LVNS) has been tested for lowering the blood pressure (BP) in patients with resistant hypertension (RH). Whereas, closed-loop LVNS (CL-LVNS) driven by a BP marker may be superior to open-loop LVNS, there are situations (e.g., exercising) when hypertension is normal. Therefore, an ideal anti-RH CL-LVNS system requires a variable to avoid stimulation in such conditions, for example, a respiratory marker ideally extracted from the LVN. As the LVN conducts respiratory signals, this study aimed to investigate if such signals can be recorded using implantable means and if a marker to monitor respiration could be derived from such recordings...
July 11, 2017: Neuromodulation: Journal of the International Neuromodulation Society
https://www.readbyqxmd.com/read/28695320/at1-and-at2-receptors-in-the-prelimbic-cortex-modulate-the-cardiovascular-response-evoked-by-acute-exposure-to-restraint-stress-in-rats
#9
Taíz F S Brasil, Aline Fassini, Fernando M Corrêa
The prelimbic cortex (PL) is an important structure in the neural pathway integrating stress responses. Brain angiotensin is involved in cardiovascular control and modulation of stress responses. Blockade of angiotensin receptors has been reported to reduce stress responses. Acute restraint stress (ARS) is a stress model, which evokes sustained blood pressure increase, tachycardia, and reduction in tail temperature. We therefore hypothesized that PL locally generated angiotensin and angiotensin receptors modulate stress autonomic responses...
July 10, 2017: Cellular and Molecular Neurobiology
https://www.readbyqxmd.com/read/28694236/fibrin-functionalization-with-synthetic-adhesive-ligands-interacting-with-%C3%AE-6%C3%AE-1-integrin-receptor-enhance-neurite-outgrowth-of-embryonic-stem-cell-derived-neural-stem-progenitors
#10
Joana Silva, Ana R Bento, Daniela Barros, Tiago L Laundos, Susana R Sousa, Pedro Quelhas, Mónica M Sousa, Ana P Pêgo, Isabel F Amaral
To enhance fibrin hydrogel affinity towards pluripotent stem cell-derived neural stem/progenitor cells (NSPCs) and its capacity to support NSPC migration and neurite extension, we explored the tethering of synthetic peptides engaging integrin α6β1, a cell receptor enriched in NSPCs. Six α6β1 integrin ligands were tested for their ability to support integrin α6β1-mediated adhesion of embryonic stem cell-derived NSPCs (ES-NSPs) and sustain ES-NSPC viability, migration, and neuronal differentiation. Due to their better performance, peptides T1, HYD1, and A5G81 were immobilized into fibrin and functionalized gels characterized in terms of peptide binding efficiency, structure and viscoelastic properties...
July 7, 2017: Acta Biomaterialia
https://www.readbyqxmd.com/read/28693584/-long-term-stability-of-stimulating-spiral-nerve-cuff-electrodes-on-human-peripheral-nerves
#11
Breanne P Christie, Max Freeberg, William D Memberg, Gilles J C Pinault, Harry A Hoyen, Dustin J Tyler, Ronald J Triolo
BACKGROUND: Electrical stimulation of the peripheral nerves has been shown to be effective in restoring sensory and motor functions in the lower and upper extremities. This neural stimulation can be applied via non-penetrating spiral nerve cuff electrodes, though minimal information has been published regarding their long-term performance for multiple years after implantation. METHODS: Since 2005, 14 human volunteers with cervical or thoracic spinal cord injuries, or upper limb amputation, were chronically implanted with a total of 50 spiral nerve cuff electrodes on 10 different nerves (mean time post-implant 6...
July 11, 2017: Journal of Neuroengineering and Rehabilitation
https://www.readbyqxmd.com/read/28689389/is-there-additive-therapeutic-effect-when-gcsf-combined-with-adipose-derived-stem-cell-in-a-rat-model-of-acute-spinal-cord-injury
#12
Joongkee Min, Jeong Hoon Kim, Kyoung Hyo Choi, Hyung Ho Yoon, Sang Ryong Jeon
OBJECTIVE: Functional and neural tissue recovery has been reported in many animal studies conducted with stem cells. However, the combined effect of cytokines and stem cells has not yet been adequately researched. Here, we analyzed the additive effects of granulocyte colony-stimulating factor (GCSF) on adipose-derived stem cells (ADSCs) infusion in the treatment of acute spinal cord injury (SCI) in rats. METHODS: Four days after intrathecal infusion tubes implantation in Sprague-Dawley rats, SCI was induced with an infinite horizon impactor...
July 2017: Journal of Korean Neurosurgical Society
https://www.readbyqxmd.com/read/28688070/long-term-performance-of-porous-platinum-coated-neural-electrodes
#13
M Leber, R Bhandari, J Mize, D J Warren, M M H Shandhi, F Solzbacher, S Negi
Over the last several years, there has been a growing interest in neural implants for the study and diagnostics of neurological disorders as well as for the symptomatic treatment of central nervous system related diseases. One of the major challenges is the trade-off between small electrode sizes for high selectivity between single neurons and large electrode-tissue interface areas for excellent stimulation and recording properties. This paper presents an approach of increasing the real surface area of the electrodes by creating a surface microstructure...
September 2017: Biomedical Microdevices
https://www.readbyqxmd.com/read/28687506/effects-of-alkaloid-rich-extract-from-mitragyna-speciosa-korth-havil-on-naloxone-precipitated-morphine-withdrawal-symptoms-and-local-field-potential-in-the-nucleus-accumbens-of-mice
#14
Dania Cheaha, Chayaporn Reakkamnuan, Jakkrit Nukitram, Somsmorn Chittrakarn, Pimpimol Phukpattaranont, Niwat Keawpradub, Ekkasit Kumarnsit
ETHNOPHARMACOLOGICAL RELEVANCE: Mitragyna speciosa (Korth.) Havil. (M. speciosa) is among the most well-known plants used in ethnic practice of Southeast Asia. It has gained increasing attention as a plant with potential to substitute morphine in addiction treatment program. However, its action on the central nervous system is controversial. AIM OF THE STUDY: This study investigated the effects of M. speciosa alkaloid extract on naloxone-precipitated morphine withdrawal and neural signaling in the nucleus accumbens (NAc, brain reward center) of mice...
July 5, 2017: Journal of Ethnopharmacology
https://www.readbyqxmd.com/read/28676240/local-nmda-receptor-hypofunction-evokes-generalized-effects-on-gamma-and-high-frequency-oscillations-and-behavior
#15
Jaime Lee, Matthew R Hudson, Terence J O'Brien, Jess Nithianantharajah, Nigel C Jones
The NMDA receptor (NMDAr) hypofunction theory of schizophrenia suggests that aberrant signaling through NMDAr underlies the pathophysiology of this disease. This is commonly modeled in rodents via treatment with NMDAr antagonists, which causes a range of behavioral effects that represent endophenotypes related to schizophrenia. These drugs also disrupt high-frequency neural oscillations within the brain, also potentially relevant to disease. We studied the effect of localized NMDAr hypofunction on the generation of neural oscillations occurring both locally and in distant brain regions, and on behaviors routinely used as endophenotypes to model psychosis in rodents...
July 1, 2017: Neuroscience
https://www.readbyqxmd.com/read/28675568/sciatic-nerve-regeneration-by-transplantation-of-schwann-cells-via-erythropoietin-controlled-releasing-polylactic-acid-multiwalled-carbon-nanotubes-gelatin-nanofibrils-neural-guidance-conduit
#16
Majid Salehi, Mahdi Naseri-Nosar, Somayeh Ebrahimi-Barough, Mohammdreza Nourani, Arash Khojasteh, Amir-Ali Hamidieh, Amir Amani, Saeed Farzamfar, Jafar Ai
The current study aimed to enhance the efficacy of peripheral nerve regeneration using an electrically conductive biodegradable porous neural guidance conduit for transplantation of allogeneic Schwann cells (SCs). The conduit was produced from polylactic acid (PLA), multiwalled carbon nanotubes (MWCNTs), and gelatin nanofibrils (GNFs) coated with the recombinant human erythropoietin-loaded chitosan nanoparticles (rhEpo-CNPs). The PLA/MWCNTs/GNFs/rhEpo-CNPs conduit had the porosity of 85.78 ± 0.70%, the contact angle of 77...
July 4, 2017: Journal of Biomedical Materials Research. Part B, Applied Biomaterials
https://www.readbyqxmd.com/read/28672008/nanofibrous-scaffolds-for-the-guidance-of-stem-cell-derived-neurons-for-auditory-nerve-regeneration
#17
Sandra Hackelberg, Samuel J Tuck, Long He, Arjun Rastogi, Christina White, Liqian Liu, Diane M Prieskorn, Ryan J Miller, Che Chan, Benjamin R Loomis, Joseph M Corey, Josef M Miller, R Keith Duncan
Impairment of spiral ganglion neurons (SGNs) of the auditory nerve is a major cause for hearing loss occurring independently or in addition to sensory hair cell damage. Unfortunately, mammalian SGNs lack the potential for autonomous regeneration. Stem cell based therapy is a promising approach for auditory nerve regeneration, but proper integration of exogenous cells into the auditory circuit remains a fundamental challenge. Here, we present novel nanofibrous scaffolds designed to guide the integration of human stem cell-derived neurons in the internal auditory meatus (IAM), the foramen allowing passage of the spiral ganglion to the auditory brainstem...
2017: PloS One
https://www.readbyqxmd.com/read/28671816/photopolymerizable-zwitterionic-polymer-patterns-control-cell-adhesion-and-guide-neural-growth
#18
Braden L Leigh, Elise Cheng, Linjing Xu, Corinne Andresen, Marlan R Hansen, C Allan Guymon
Developing materials that reduce or eliminate fibrosis encapsulation of neural prosthetic implants could significantly enhance implant fidelity by improving the tissue/electrode array interface. Here, we report on the photografting and patterning of two zwitterionic materials, sulfobetaine methacrylate (SBMA) and carboxybetaine methacrylate (CBMA) for controlling the adhesion and directionality of cells relevant to neural prosthetics. CBMA and SBMA polymers were photopolymerized and grafted on glass surfaces then characterized by X-ray photoelectron spectroscopy, water contact angle, and protein adsorption...
July 3, 2017: Biomacromolecules
https://www.readbyqxmd.com/read/28658132/emergency-1-stage-anterior-approach-for-cervical-spine-infection-complicated-by-epidural-abscess
#19
Haoxi Li, Zhaoxiong Chen, Zhiyao Yong, Xinhua Li, Yufeng Huang, Desheng Wu
It was a retrospective analysis.The aim of the study was to explore the safety and reliability of emergency 1-stage radical debridement and reconstruction using titanium mesh filled with autologous bone for patients with cervical spine infection complicated by epidural abscess.At present, cervical spine infection complicated by epidural abscess is known as a severe spine disease. Recently, case report of this disease is showing quite an increasing tendency, particularly in economically undeveloped areas and countries...
June 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28653858/transplantation-of-a-human-tissue-engineered-bowel-in-an-athymic-rat-model
#20
Elie Zakhem, Riccardo Tamburrini, Giuseppe Orlando, Kenneth L Koch, Khalil N Bitar
Intestinal failure is a serious clinical condition characterized by loss of motility, absorptive function, and malnutrition. Current treatments do not provide the optimal solution for patients due to the numerous resulting complications. A bioengineered bowel that contains the necessary cellular components provides a viable option for patients. In this study, human tissue-engineered bowel (hTEB) was developed using a technique, whereby human-sourced smooth muscle cells were aligned and neoinnervated using human-sourced neural progenitor cells, resulting in the formation of intrinsically innervated smooth muscle sheets...
June 27, 2017: Tissue Engineering. Part C, Methods
keyword
keyword
49340
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"