WorldWideScience

Sample records for auditory brain stem implants

  1. Brain stem auditory evoked responses in chronic alcoholics.

    OpenAIRE

    Chan, Y W; McLeod, J G; Tuck, R R; Feary, P A

    1985-01-01

    Brain stem auditory evoked responses (BAERs) were performed on 25 alcoholic patients with Wernicke-Korsakoff syndrome, 56 alcoholic patients without Wernicke-Korsakoff syndrome, 24 of whom had cerebellar ataxia, and 37 control subjects. Abnormal BAERs were found in 48% of patients with Wernicke-Korsakoff syndrome, in 25% of alcoholic patients without Wernicke-Korsakoff syndrome but with cerebellar ataxia, and in 13% of alcoholic patients without Wernicke-Korsakoff syndrome or ataxia. The mean...

  2. Conductive Hearing Loss during Infancy: Effects on Later Auditory Brain Stem Electrophysiology.

    Science.gov (United States)

    Gunnarson, Adele D.; Finitzo, Terese

    1991-01-01

    Long-term effects on auditory electrophysiology from early fluctuating hearing loss were studied in 27 children, aged 5 to 7 years, who had been evaluated originally in infancy. Findings suggested that early fluctuating hearing loss disrupts later auditory brain stem electrophysiology. (Author/DB)

  3. Auditory Brain Stem Processing in Reptiles and Amphibians: Roles of Coupled Ears

    DEFF Research Database (Denmark)

    Willis, Katie L.; Christensen-Dalsgaard, Jakob; Carr, Catherine

    2014-01-01

    of anurans (frogs), reptiles (including birds), and mammals should all be more similar within each group than among the groups. Although there is large variation in the peripheral auditory system, there is evidence that auditory brain stem nuclei in tetrapods are homologous and have similar functions among...

  4. Brain stem auditory evoked responses in human infants and adults

    Science.gov (United States)

    Hecox, K.; Galambos, R.

    1974-01-01

    Brain stem evoked potentials were recorded by conventional scalp electrodes in infants (3 weeks to 3 years of age) and adults. The latency of one of the major response components (wave V) is shown to be a function both of click intensity and the age of the subject; this latency at a given signal strength shortens postnatally to reach the adult value (about 6 msec) by 12 to 18 months of age. The demonstrated reliability and limited variability of these brain stem electrophysiological responses provide the basis for an optimistic estimate of their usefulness as an objective method for assessing hearing in infants and adults.

  5. Correlation of auditory brain stem response and the MRI measurements in neuro-degenerative disorders

    Energy Technology Data Exchange (ETDEWEB)

    Kamei, Hidekazu (Tokyo Women' s Medical Coll. (Japan))

    1989-06-01

    The purpose of this study is to elucidate correlations of several MRI measurements of the cranium and brain, functioning as a volume conductor, to the auditory brain stem response (ABR) in neuro-degenerative disorders. The subjects included forty-seven patients with spinocerebellar degeneration (SCD) and sixteen of amyotrophic lateral sclerosis (ALS). Statistically significant positive correlations were found between I-V and III-V interpeak latencies (IPLs) and the area of cranium and brain in the longitudinal section of SCD patients, and between I-III and III-V IPLs and the area in the longitudinal section of those with ALS. And, also there were statistically significant correlations between the amplitude of the V wave and the area of brain stem as well as that of the cranium in the longitudinal section of SCD patients, and between the amplitude of the V wave and the area of the cerebrum in the longitudinal section of ALS. In conclusion, in the ABR, the IPLs were prolonged and the amplitude of the V wave was decreased while the MRI size of the cranium and brain increased. When the ABR is applied to neuro-degenerative disorders, it might be important to consider not only the conduction of the auditory tracts in the brain stem, but also the correlations of the size of the cranium and brain which act as a volume conductor. (author).

  6. Early changes of auditory brain stem evoked response after radiotherapy for nasopharyngeal carcinoma - a prospective study

    Energy Technology Data Exchange (ETDEWEB)

    Lau, S.K.; Wei, W.I.; Sham, J.S.T.; Choy, D.T.K.; Hui, Y. (Queen Mary Hospital, Hong Kong (Hong Kong))

    1992-10-01

    A prospective study of the effect of radiotherapy for nasopharyngeal carcinoma on hearing was carried out on 49 patients who had pure tone, impedance audiometry and auditory brain stem evoked response (ABR) recordings before, immediately, three, six and 12 months after radiotherapy. Fourteen patients complained of intermittent tinnitus after radiotherapy. We found that 11 initially normal ears of nine patients developed a middle ear effusion, three to six months after radiotherapy. There was mixed sensorineural and conductive hearing impairment after radiotherapy. Persistent impairment of ABR was detected immediately after completion of radiotherapy. The waves I-III and I-V interpeak latency intervals were significantly prolonged one year after radiotherapy. The study shows that radiotherapy for nasopharyngeal carcinoma impairs hearing by acting on the middle ear, the cochlea and the brain stem auditory pathway. (Author).

  7. Characteristics of brain stem auditory evoked potentials in children with hearing impairment due to infectious diseases.

    Science.gov (United States)

    Ječmenica, Jovana Radovan; Opančina, Aleksandra Aleksandar Bajec

    2015-05-01

    Among objective audiologic tests, the most important were tests of brain stem auditory evoked potentials. The objective of the study was to test the configuration, degree of hearing loss, and response characteristics of auditory brain stem evoked potentials in children with hearing loss occurred due to infectious disease. A case control study design was used. The study group consisted of 54 patients referred for a hearing test because of infectious diseases caused by other agents or that occurred as congenital infection. Infectious agents have led to the emergence of various forms of sensorineural hearing loss. We have found deviations from the normal values of absolute and interwave latencies in some children in our group. We found that in the group of children who had the diseases such as purulent meningitis, or were born with rubella virus and cytomegalovirus infection, a retrocochlear damage was present in children with and without cochlear damage.

  8. Development and modulation of intrinsic membrane properties control the temporal precision of auditory brain stem neurons.

    Science.gov (United States)

    Franzen, Delwen L; Gleiss, Sarah A; Berger, Christina; Kümpfbeck, Franziska S; Ammer, Julian J; Felmy, Felix

    2015-01-15

    Passive and active membrane properties determine the voltage responses of neurons. Within the auditory brain stem, refinements in these intrinsic properties during late postnatal development usually generate short integration times and precise action-potential generation. This developmentally acquired temporal precision is crucial for auditory signal processing. How the interactions of these intrinsic properties develop in concert to enable auditory neurons to transfer information with high temporal precision has not yet been elucidated in detail. Here, we show how the developmental interaction of intrinsic membrane parameters generates high firing precision. We performed in vitro recordings from neurons of postnatal days 9-28 in the ventral nucleus of the lateral lemniscus of Mongolian gerbils, an auditory brain stem structure that converts excitatory to inhibitory information with high temporal precision. During this developmental period, the input resistance and capacitance decrease, and action potentials acquire faster kinetics and enhanced precision. Depending on the stimulation time course, the input resistance and capacitance contribute differentially to action-potential thresholds. The decrease in input resistance, however, is sufficient to explain the enhanced action-potential precision. Alterations in passive membrane properties also interact with a developmental change in potassium currents to generate the emergence of the mature firing pattern, characteristic of coincidence-detector neurons. Cholinergic receptor-mediated depolarizations further modulate this intrinsic excitability profile by eliciting changes in the threshold and firing pattern, irrespective of the developmental stage. Thus our findings reveal how intrinsic membrane properties interact developmentally to promote temporally precise information processing.

  9. Effect of Acupuncture on the Auditory Evoked Brain Stem Potential in Parkinson's Disease

    Institute of Scientific and Technical Information of China (English)

    王玲玲; 何崇; 刘跃光; 朱莉莉

    2002-01-01

    @@ Under the auditory evoked brain stem potential (ABP) examination, the latent period of V wave and the intermittent periods of III-V peak and I-V peak were significantly shortened in Parkinson's disease patients of the treatment group (N=29) after acupuncture treatment. The difference of cumulative scores in Webster's scale was also decreased in correlation analysis. The increase of dopamine in the brain and the excitability of the dopamine neurons may contribute to the therapeutic effects, in TCM terms, of subduing the pathogenic wind and tranquilizing the mind.

  10. Effect of acupuncture on the auditory evoked brain stem potential in Parkinson's disease.

    Science.gov (United States)

    Wang, Lingling; He, Chong; Liu, Yueguang; Zhu, Lili

    2002-03-01

    Under the auditory evoked brain stem potential (ABP) examination, the latent period of V wave and the intermittent periods of III-V peak and I-V peak were significantly shortened in Parkinson's disease patients of the treatment group (N = 29) after acupuncture treatment. The difference of cumulative scores in Webster's scale was also decreased in correlation analysis. The increase of dopamine in the brain and the excitability of the dopamine neurons may contribute to the therapeutic effects, in TCM terms, of subduing the pathogenic wind and tranquilizing the mind.

  11. Survival of human embryonic stem cells implanted in the guinea pig auditory epithelium

    Science.gov (United States)

    Young Lee, Min; Hackelberg, Sandra; Green, Kari L.; Lunghamer, Kelly G.; Kurioka, Takaomi; Loomis, Benjamin R.; Swiderski, Donald L.; Duncan, R. Keith; Raphael, Yehoash

    2017-01-01

    Hair cells in the mature cochlea cannot spontaneously regenerate. One potential approach for restoring hair cells is stem cell therapy. However, when cells are transplanted into scala media (SM) of the cochlea, they promptly die due to the high potassium concentration. We previously described a method for conditioning the SM to make it more hospitable to implanted cells and showed that HeLa cells could survive for up to a week using this method. Here, we evaluated the survival of human embryonic stem cells (hESC) constitutively expressing GFP (H9 Cre-LoxP) in deaf guinea pig cochleae that were pre-conditioned to reduce potassium levels. GFP-positive cells could be detected in the cochlea for at least 7 days after the injection. The cells appeared spherical or irregularly shaped, and some were aggregated. Flushing SM with sodium caprate prior to transplantation resulted in a lower proportion of stem cells expressing the pluripotency marker Oct3/4 and increased cell survival. The data demonstrate that conditioning procedures aimed at transiently reducing the concentration of potassium in the SM facilitate survival of hESCs for at least one week. During this time window, additional procedures can be applied to initiate the differentiation of the implanted hESCs into new hair cells. PMID:28387239

  12. Subthreshold K+ Channel Dynamics Interact With Stimulus Spectrum to Influence Temporal Coding in an Auditory Brain Stem Model

    Science.gov (United States)

    Day, Mitchell L.; Doiron, Brent; Rinzel, John

    2013-01-01

    Neurons in the auditory brain stem encode signals with exceptional temporal precision. A low-threshold potassium current, IKLT, present in many auditory brain stem structures and thought to enhance temporal encoding, facilitates spike selection of rapid input current transients through an associated dynamic gate. Whether the dynamic nature of IKLT interacts with the timescales in spectrally rich input to influence spike encoding remains unclear. We examine the general influence of IKLT on spike encoding of stochastic stimuli using a pattern classification analysis between spike responses from a ventral cochlear nucleus (VCN) model containing IKLT, and the same model with the dynamics removed. The influence of IKLT on spike encoding depended on the spectral content of the current stimulus such that maximal IKLT influence occurred for stimuli with power concentrated at frequencies low enough (<500 Hz) to allow IKLT activation. Further, broadband stimuli significantly decreased the influence of IKLT on spike encoding, suggesting that broadband stimuli are not well suited for investigating the influence of some dynamic membrane nonlinearities. Finally, pattern classification on spike responses was performed for physiologically realistic conductance stimuli created from various sounds filtered through an auditory nerve (AN) model. Regardless of the sound, the synaptic input arriving at VCN had similar low-pass power spectra, which led to a large influence of IKLT on spike encoding, suggesting that the subthreshold dynamics of IKLT plays a significant role in shaping the response of real auditory brain stem neurons. PMID:18057115

  13. Physiological modulators of Kv3.1 channels adjust firing patterns of auditory brain stem neurons.

    Science.gov (United States)

    Brown, Maile R; El-Hassar, Lynda; Zhang, Yalan; Alvaro, Giuseppe; Large, Charles H; Kaczmarek, Leonard K

    2016-07-01

    Many rapidly firing neurons, including those in the medial nucleus of the trapezoid body (MNTB) in the auditory brain stem, express "high threshold" voltage-gated Kv3.1 potassium channels that activate only at positive potentials and are required for stimuli to generate rapid trains of actions potentials. We now describe the actions of two imidazolidinedione derivatives, AUT1 and AUT2, which modulate Kv3.1 channels. Using Chinese hamster ovary cells stably expressing rat Kv3.1 channels, we found that lower concentrations of these compounds shift the voltage of activation of Kv3.1 currents toward negative potentials, increasing currents evoked by depolarization from typical neuronal resting potentials. Single-channel recordings also showed that AUT1 shifted the open probability of Kv3.1 to more negative potentials. Higher concentrations of AUT2 also shifted inactivation to negative potentials. The effects of lower and higher concentrations could be mimicked in numerical simulations by increasing rates of activation and inactivation respectively, with no change in intrinsic voltage dependence. In brain slice recordings of mouse MNTB neurons, both AUT1 and AUT2 modulated firing rate at high rates of stimulation, a result predicted by numerical simulations. Our results suggest that pharmaceutical modulation of Kv3.1 currents represents a novel avenue for manipulation of neuronal excitability and has the potential for therapeutic benefit in the treatment of hearing disorders.

  14. Functional outcome of auditory implants in hearing loss.

    Science.gov (United States)

    Di Girolamo, S; Saccoccio, A; Giacomini, P G; Ottaviani, F

    2007-01-01

    The auditory implant provides a new mechanism for hearing when a hearing aid is not enough. It is the only medical technology able to functionally restore a human sense i.e. hearing. The auditory implant is very different from a hearing aid. Hearing aids amplify sound. Auditory implants compensate for damaged or non-working parts of the inner ear because they can directly stimulate the acoustic nerve. There are two principal types of auditory implant: the cochlear implant and the auditory brainstem implant. They have common basic characteristics, but different applications. A cochlear implant attempts to replace a function lost by the cochlea, usually due to an absence of functioning hair cells; the auditory brainstem implant (ABI) is a modification of the cochlear implant, in which the electrode array is placed directly into the brain when the acoustic nerve is not anymore able to carry the auditory signal. Different types of deaf or severely hearing-impaired patients choose auditory implants. Both children and adults can be candidates for implants. The best age for implantation is still being debated, but most children who receive implants are between 2 and 6 years old. Earlier implantation seems to perform better thanks to neural plasticity. The decision to receive an implant should involve a discussion with many medical specialists and an experienced surgeon.

  15. A developmental study of bone conduction auditory brain stem response in infants.

    Science.gov (United States)

    Yang, E Y; Rupert, A L; Moushegian, G

    1987-08-01

    Two studies, vibrator placement and masking, were performed to evaluate the developmental aspect of bone conduction auditory brain stem response (ABR) in human infants. Subject groups included newborns, 1-yr-olds, and adults. In the vibrator studies, ABRs were obtained from placements of the bone conduction vibrator on the frontal, occipital, and temporal bones. Results showed that temporal placements in neonates and 1-yr-olds produce significantly shorter wave V latencies of ABR than frontal or occipital placements. In adults, differences of wave V latencies from various vibrator placements were comparatively small. In the masking studies, ABRs were acquired from vibrator placements at the temporal bone in the presence of ipsilateral air conducted masking noise from the experimental groups. Results showed that interaural attenuations of bone conduction click stimuli are the largest in neonates, somewhat smaller from 1-yr-olds, and the smallest in adults. The findings of this research strongly suggest that temporal placements for bone conduction ABR should be used, in some instances, when testing infants and 1-yr-olds. The results of this study support the proposition that bone conduction ABR is a feasible and reliable diagnostic tool in testing infants.

  16. [Effect of sleep deprivation on visual evoked potentials and brain stem auditory evoked potentials in epileptics].

    Science.gov (United States)

    Urumova, L T; Kovalenko, G A; Tsunikov, A I; Sumskiĭ, L I

    1984-01-01

    The article reports on the first study of the evoked activity of the brain in epileptic patients (n = 20) following sleep deprivation. An analysis of the data obtained has revealed a tendency to the shortening of the peak latent intervals of visual evoked potentials in the range of 100-200 mu sec and the V component and the interpeak interval III-V of evoked auditory trunk potentials in patients with temporal epilepsy. The phenomenon may indicate the elimination of stabilizing control involving the specific conductive pathways and, possibly, an accelerated conduction of a specific sensor signal.

  17. Evaluation of auditory brain-stem evoked response in middle: Aged type 2 diabetes mellitus with normal hearing subjects

    Directory of Open Access Journals (Sweden)

    Debadatta Mahallik

    2014-01-01

    Full Text Available Background: Diabetes mellitus (DM is commonly metabolic disorders of carbohydrate in which blood glucose levels are abnormally high due to relative or absolute insulin deficiency. In addition, it is characterized by abnormal metabolism of fat, protein resulting from insulin deficit or insulin action, or both. There are two broad categories of DM are designated as type 1 and type 2. Type 2 diabetes is due to predominantly insulin resistance with relative insulin deficiency noninsulin-dependent DM. Type 2 diabetes is much more common than insulin-dependent DM. Objectives: The aim of this study was to assess, if there is any abnormality in neural conduction in auditory brain-stem pathway in type 2 DM patients having normal hearing sensitivity when compared to age-matched healthy populations. Materials and Methods: This study included middle - aged 25 subjects having normal hearing with diabetes type 2 mellitus. All were submitted to the full audiological history taking, otological examination, basic audiological evaluation and auditory brain-stem response audiometry which was recorded in both ears, followed by calculation of the absolute latencies of wave I, III and V, as well as interpeak latencies I-III, III-V, I-V. Results: Type 2 DM patients showed significant prolonged absolute latencies of I, III (P = 0.001 and interpeak latencies I-III, III-V and I-V in left ear (P = 0.001 and absolute latencies of I, V (P = 0.001, interpeak latencies III-V was statistically significant in right ear. Conclusions: The prolonged absolute latencies and interpeak latencies suggests abnormal neural firing synchronization or in the transmission in the auditory pathways in normal hearing type 2 diabetes mellitus patients.

  18. Auditory and audio-visual processing in patients with cochlear, auditory brainstem, and auditory midbrain implants: An EEG study.

    Science.gov (United States)

    Schierholz, Irina; Finke, Mareike; Kral, Andrej; Büchner, Andreas; Rach, Stefan; Lenarz, Thomas; Dengler, Reinhard; Sandmann, Pascale

    2017-04-01

    There is substantial variability in speech recognition ability across patients with cochlear implants (CIs), auditory brainstem implants (ABIs), and auditory midbrain implants (AMIs). To better understand how this variability is related to central processing differences, the current electroencephalography (EEG) study compared hearing abilities and auditory-cortex activation in patients with electrical stimulation at different sites of the auditory pathway. Three different groups of patients with auditory implants (Hannover Medical School; ABI: n = 6, CI: n = 6; AMI: n = 2) performed a speeded response task and a speech recognition test with auditory, visual, and audio-visual stimuli. Behavioral performance and cortical processing of auditory and audio-visual stimuli were compared between groups. ABI and AMI patients showed prolonged response times on auditory and audio-visual stimuli compared with NH listeners and CI patients. This was confirmed by prolonged N1 latencies and reduced N1 amplitudes in ABI and AMI patients. However, patients with central auditory implants showed a remarkable gain in performance when visual and auditory input was combined, in both speech and non-speech conditions, which was reflected by a strong visual modulation of auditory-cortex activation in these individuals. In sum, the results suggest that the behavioral improvement for audio-visual conditions in central auditory implant patients is based on enhanced audio-visual interactions in the auditory cortex. Their findings may provide important implications for the optimization of electrical stimulation and rehabilitation strategies in patients with central auditory prostheses. Hum Brain Mapp 38:2206-2225, 2017. © 2017 Wiley Periodicals, Inc.

  19. Auditory evaluation of the microcephalic children with brain stem evoked response audiometry (BERA).

    Science.gov (United States)

    Das, Piyali; Bandyopadhyay, Manimay; Ghugare, Balaji W; Ghate, Jayshree; Singh, Ramji

    2010-01-01

    Microcephaly implies a reduced occipito-frontal circumference (Audiometry (BERA) to locate the exact site of lesion resulting in the auditory impairment, so that appropriate early rehabilitative measures can be taken. The study revealed that absolute peak latency of wave V, inter peak latencies of III-V and I-V were significantly higher (P- value < 0.05 in each case) in microcephalics than the normal children. Auditory impairment in microcephaly is a common neurodeficit that can be authentically assessed by BERA. The hearing impairment in microcephalics is mostly due to insufficiency of central components of auditory pathway at the level of brainstem, function of peripheral structures being almost within normal limit.

  20. Neuronal coupling by endogenous electric fields: cable theory and applications to coincidence detector neurons in the auditory brain stem.

    Science.gov (United States)

    Goldwyn, Joshua H; Rinzel, John

    2016-04-01

    The ongoing activity of neurons generates a spatially and time-varying field of extracellular voltage (Ve). This Ve field reflects population-level neural activity, but does it modulate neural dynamics and the function of neural circuits? We provide a cable theory framework to study how a bundle of model neurons generates Ve and how this Ve feeds back and influences membrane potential (Vm). We find that these "ephaptic interactions" are small but not negligible. The model neural population can generate Ve with millivolt-scale amplitude, and this Ve perturbs the Vm of "nearby" cables and effectively increases their electrotonic length. After using passive cable theory to systematically study ephaptic coupling, we explore a test case: the medial superior olive (MSO) in the auditory brain stem. The MSO is a possible locus of ephaptic interactions: sounds evoke large (millivolt scale)Vein vivo in this nucleus. The Ve response is thought to be generated by MSO neurons that perform a known neuronal computation with submillisecond temporal precision (coincidence detection to encode sound source location). Using a biophysically based model of MSO neurons, we find millivolt-scale ephaptic interactions consistent with the passive cable theory results. These subtle membrane potential perturbations induce changes in spike initiation threshold, spike time synchrony, and time difference sensitivity. These results suggest that ephaptic coupling may influence MSO function.

  1. Conventional and cross-correlation brain-stem auditory evoked responses in the white leghorn chick: rate manipulations

    Science.gov (United States)

    Burkard, R.; Jones, S.; Jones, T.

    1994-01-01

    Rate-dependent changes in the chick brain-stem auditory evoked response (BAER) using conventional averaging and a cross-correlation technique were investigated. Five 15- to 19-day-old white leghorn chicks were anesthetized with Chloropent. In each chick, the left ear was acoustically stimulated. Electrical pulses of 0.1-ms duration were shaped, attenuated, and passed through a current driver to an Etymotic ER-2 which was sealed in the ear canal. Electrical activity from stainless-steel electrodes was amplified, filtered (300-3000 Hz) and digitized at 20 kHz. Click levels included 70 and 90 dB peSPL. In each animal, conventional BAERs were obtained at rates ranging from 5 to 90 Hz. BAERs were also obtained using a cross-correlation technique involving pseudorandom pulse sequences called maximum length sequences (MLSs). The minimum time between pulses, called the minimum pulse interval (MPI), ranged from 0.5 to 6 ms. Two BAERs were obtained for each condition. Dependent variables included the latency and amplitude of the cochlear microphonic (CM), wave 2 and wave 3. BAERs were observed in all chicks, for all level by rate combinations for both conventional and MLS BAERs. There was no effect of click level or rate on the latency of the CM. The latency of waves 2 and 3 increased with decreasing click level and increasing rate. CM amplitude decreased with decreasing click level, but was not influenced by click rate for the 70 dB peSPL condition. For the 90 dB peSPL click, CM amplitude was uninfluenced by click rate for conventional averaging. For MLS BAERs, CM amplitude was similar to conventional averaging for longer MPIs.(ABSTRACT TRUNCATED AT 250 WORDS).

  2. Evaluation of brain stem auditory evoked potentials in stable patients with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Gupta Prem

    2008-01-01

    Full Text Available Though there are few studies addressing brainstem auditory evoked potentials (BAEP in patients with chronic obstructive pulmonary disease (COPD, subclinical BAEP abnormalities in stable COPD patients have not been studied. The present study aimed to evaluate the BAEP abnormalities in this study group. Materials and Methods : In the present study, 80 male subjects were included: COPD group comprised 40 smokers with stable COPD with no clinical neuropathy; 40 age-matched healthy volunteers served as the control group. Latencies of BAEP waves I, II, III, IV, and V, together with interpeak latencies (IPLs of I-III, I-V, and III-V, and amplitudes of waves I-Ia and V-Va were studied in both the groups to compare the BAEP abnormalities in COPD group; the latter were correlated with patient characteristics and Mini-Mental Status Examination Questionnaire (MMSEQ scores to seek any significant correlation. Results: Twenty-six (65% of the 40 COPD patients had BAEP abnormalities. We observed significantly prolonged latencies of waves I, III, V over left ear and waves III, IV, V over right ear; increased IPLs of I-V, III-V over left ear and of I-III, I-V, III-V over right side. Amplitudes of waves I-Ia and V-Va were decreased bilaterally. Over left ear, the latencies of wave I and III were significantly correlated with FEV 1 ; and amplitude of wave I-Ia, with smoking pack years. A weak positive correlation between amplitude of wave I-Ia and duration of illness; and a weak negative correlation between amplitude of wave V-Va and MMSEQ scores were seen over right side. Conclusions : We observed significant subclinical BAEP abnormalities on electrophysiological evaluation in studied stable COPD male patients having mild-to-moderate airflow obstruction.

  3. Analysis of brain-stem auditory evoked potential and visual evoked potential in patients with Parkinson disease

    Institute of Scientific and Technical Information of China (English)

    Qiaorong Deng; Jianzhong Deng; Yanmin Zhao; Xiaohai Yan; Pin Chen

    2006-01-01

    BACKGROUND: With the development of neuroelectrophysiology, it had been identified that all kinds of evoked potentials might reflect the functional status of corresponding pathway. Evoked potentials recruited in the re search of PD, it can be known whether other functional pathway of nervous system is impaired. OBJECTIVE: To observe whether brainstem auditory and visual passageway are impaired in patients with Parkinson disease (PD), and compare with non-PD patients concurrently. DESIGN: A non-randomized concurrent controlled observation. SETTINGS: Henan Provincial Tumor Hospital; Anyang District Hospital. PARTICIPANTS: Thirty-two cases of PD outpatients and inpatients, who registered in the Department of Neurology, Anyang District Hospital from October 1997 to February 2006, were enrolled as the PD group, including 20 males and 12 females, aged 50-72 years old. Inclusive criteria: In accordance with the diagnostic criteria of PD recommended by the dyskinesia and PD group of neurology branch of Chinese Medical Association. Patients with diseases that could cause Parkinson syndrome were excluded by CT scanning or MRI examination. Meanwhile, 30 cases with non-neurological disease were selected from the Department of Internal Medicine of our hospital as the control group, including 19 males and 11 females, aged 45-70 years old. Including criteria: Without history of neurological disease or psychiatric disease; showing normal image on CT. And PD, Parkinson syndrome and Parkinsonism-plus were excluded by professional neurologist. All the patients were informed and agreed with the examination and clinical observation. METHODS: The electrophysiological examination and clinical observation of the PD patients and controls were conducted. The Reporter type 4-channel evoked potential machine (Italy) was used to check brain-stem auditory evoked potential (BAEP) and visual evoked potential (VEP). Why to be examined was explained to test taker. BAEP recording electrode was plac

  4. Activation of expression of brain-derived neurotrophic factor at the site of implantation of allogenic and xenogenic neural stem (progenitor) cells in rats with ischemic cortical stroke.

    Science.gov (United States)

    Chekhonin, V P; Lebedev, S V; Volkov, A I; Pavlov, K A; Ter-Arutyunyants, A A; Volgina, N E; Savchenko, E A; Grinenko, N F; Lazarenko, I P

    2011-02-01

    Ischemic stroke was modeled in the sensorimotor zone of the brain cortex in adult rats. Rat embryonic nervous tissue, neural stem cells from human olfactory epithelium, and rat fibroblasts (cell control) were implanted into the peri-infarction area of rats of different groups immediately after stroke modeling. Expression of BDNF mRNA was analyzed 7 days after surgery by real-time PCR. BDNF expression in cell preparation before their implantation was minimum. The expression of BDNF mRNA increased by 5-6 times in the areas of implantation of rat fibroblasts and human olfactory epithelium and by 23 times in the area of implantation of rat embryonic nervous tissue compared to periinfarction areas without cell implantation. These findings confirm the possibility of realization of the therapeutic effects of neural stem cells via expression of trophic factors.

  5. Cortical Auditory Evoked Potentials in Unsuccessful Cochlear Implant Users

    Science.gov (United States)

    Munivrana, Boska; Mildner, Vesna

    2013-01-01

    In some cochlear implant users, success is not achieved in spite of optimal clinical factors (including age at implantation, duration of rehabilitation and post-implant hearing level), which may be attributed to disorders at higher levels of the auditory pathway. We used cortical auditory evoked potentials to investigate the ability to perceive…

  6. Hydrogel limits stem cell dispersal in the deaf cochlea: implications for cochlear implants

    Science.gov (United States)

    Nayagam, Bryony A.; Backhouse, Steven S.; Cimenkaya, Cengiz; Shepherd, Robert K.

    2012-12-01

    Auditory neurons provide the critical link between a cochlear implant and the brain in deaf individuals, therefore their preservation and/or regeneration is important for optimal performance of this neural prosthesis. In cases where auditory neurons are significantly depleted, stem cells (SCs) may be used to replace the lost population of neurons, thereby re-establishing the critical link between the periphery (implant) and the brain. For such a therapy to be therapeutically viable, SCs must be differentiated into neurons, retained at their delivery site and damage caused to the residual auditory neurons minimized. Here we describe the transplantation of SC-derived neurons into the deaf cochlea, using a peptide hydrogel to limit their dispersal. The described approach illustrates that SCs can be delivered to and are retained within the basal turn of the cochlea, without a significant loss of endogenous auditory neurons. In addition, the tissue response elicited from this surgical approach was restricted to the surgical site and did not extend beyond the cochlear basal turn. Overall, this approach illustrates the feasibility of targeted cell delivery into the mammalian cochlea using hydrogel, which may be useful for future cell-based transplantation strategies, for combined treatment with a cochlear implant to restore function.

  7. Therapeutic potential of stem cells in auditory hair cell repair

    Directory of Open Access Journals (Sweden)

    Ryuji Hata

    2009-01-01

    Full Text Available The prevalence of acquired hearing loss is very high. About 10% of the total population and more than one third of the population over 65 years suffer from debilitating hearing loss. The most common type of hearing loss in adults is idiopathic sudden sensorineural hearing loss (ISSHL. In the majority of cases, ISSHL is permanent and typically associated with loss of sensory hair cells in the organ of Corti. Following the loss of sensory hair cells, the auditory neurons undergo secondary degeneration. Sensory hair cells and auditory neurons do not regenerate throughout life, and loss of these cells is irreversible and cumulative. However, recent advances in stem cell biology have gained hope that stem cell therapy comes closer to regenerating sensory hair cells in humans. A major advance in the prospects for the use of stem cells to restore normal hearing comes with the recent discovery that hair cells can be generated ex vivo from embryonic stem (ES cells, adult inner ear stem cells and neural stem cells. Furthermore, there is increasing evidence that stem cells can promote damaged cell repair in part by secreting diffusible molecules such as growth factors. These results suggest that stem-cell-based treatment regimens can be applicable to the damaged inner ear as future clinical applications.Previously we have established an animal model of cochlear ischemia in gerbils and showed progressive hair cell loss up to 4 days after ischemia. Auditory brain stem response (ABR recordings have demonstrated that this gerbil model displays severe deafness just after cochlear ischemia and gradually recovers thereafter. These pathological findings and clinical manifestations are reminiscent of ISSHL in humans. In this study, we have shown the effectiveness of stem cell therapy by using this animal model of ISSHL.

  8. Hearing Restoration with Auditory Brainstem Implant

    Science.gov (United States)

    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

  9. Brain-stem auditory evoked responses during microvascular decompression for trigeminal neuralgia: Predicting post-operative hearing loss

    Directory of Open Access Journals (Sweden)

    Ramnarayan Ramachandran

    2006-01-01

    Full Text Available Context: The importance of brainstem auditory evoked potential monitoring in reducing hearing loss during microvascular decompression for trigeminal neuralgia is now accepted. However the extent of the changes in the pattern of these potentials and the safe limits to which these changes are relevant in reducing postoperative hearing loss have not been established. Aims: The aim of this study is to quantify these changes and relate these to the postoperative hearing loss. Settings and Design: This study was done at the Walton Centre for neurology and neurosurgery, Liverpool, United Kingdom. The study was designed to give a measure of the change in the wave pattern following microvascular decompression and relate it to postoperative hearing loss. Materials and Methods: Seventy-five patients undergoing microvascular decompression for trigeminal neuralgia had preoperative and postoperative hearing assessments and intraoperative brainstem auditory evoked potential monitoring. Statistical Analysis Used: Chi-square tests. Results: It was found that the wave V latency was increased by more than 0.9ms in nine patients, eight of whom suffered significant postoperative hearing loss as demonstrated by audiometry. It was also seen that progressive decrease in amplitude of wave V showed progressive hearing loss with 25% loss when amplitude fell by 50 and 100% loss when wave V was lost completely. However most of the patients did not have a clinically manifest hearing loss. Conclusions: A per-operative increase in the latency of wave V greater than 0.9 ms and a fall of amplitude of wave V of more than 50% indicates a risk to hearing.

  10. Noise-gated encoding of slow inputs by auditory brain stem neurons with a low-threshold K+ current.

    Science.gov (United States)

    Gai, Yan; Doiron, Brent; Kotak, Vibhakar; Rinzel, John

    2009-12-01

    Phasic neurons, which do not fire repetitively to steady depolarization, are found at various stages of the auditory system. Phasic neurons are commonly described as band-pass filters because they do not respond to low-frequency inputs even when the amplitude is large. However, we show that phasic neurons can encode low-frequency inputs when noise is present. With a low-threshold potassium current (I(KLT)), a phasic neuron model responds to rising and falling phases of a subthreshold low-frequency signal with white noise. When the white noise was low-pass filtered, the phasic model also responded to the signal's trough but still not to the peak. In contrast, a tonic neuron model fired mostly to the signal's peak. To test the model predictions, whole cell slice recordings were obtained in the medial (MSO) and lateral (LSO) superior olivary neurons in gerbil from postnatal day 10 (P10) to 22. The phasic MSO neurons with strong I(KLT), mostly from gerbils aged P17 or older, showed firing patterns consistent with the preceding predictions. Moreover, injecting a virtual I(KLT) into weak-phasic MSO and tonic LSO neurons with putative weak or no I(KLT) (from gerbils younger than P17) shifted the neural response from the signal's peak to the rising phase. These findings advance our knowledge about how noise gates the signal pathway and how phasic neurons encode slow envelopes of sounds with high-frequency carriers.

  11. Auditory brain-stem response, CT and MR imaging in a family with classical type Pelizaeus-Merzbacher Disease

    Energy Technology Data Exchange (ETDEWEB)

    Shiomi, M.; Ookuni, H.; Sugita, T.

    1987-05-01

    A family in which 5 males in successive generations were clinically suspected to be affected with the classical X-linked recessive form of Pelizaeus-Merzbacher disease (PMD) is presented. Two brothers and their maternal uncle were examined by one of the authors (MS). In two brothers, aged 3 years and 2 years, the disease became obvious within a month after birth with nystagmus and head tremor. Head control and sitting were achieved at the age of 18 months at which time they began to speak. They could not stand nor walk without support. They had dysmetria, weakness and hyper-reflexia of lower extremities, and mild mental retardation. Their maternal uncle, aged 37 years, showed psychomotor retardation from birth and subsequently developed spastic paraplegia. He had been able to walk with crutches until adolescence. He had dysmetria, scanning speech, athetoid posture of fingers and significant intellectual deficits. Auditory brainstem response in both brothers revealed well defined waves I and II, low amplitude wave III and an absence of all subsequent components. CT demonstrated mild cerebral atrophy in the elder brother and was normal in the younger brother, but in their uncle, CT showed atrophy of the brainstem, cerebellum and cerebrum, and low density of the white matter of the centrum semiovale. MRI was performed in both brothers. Although the brainstem, the internal capsule and the thalamus were myelinated, the myelination in the subcortical white matter was restricted to periventricular regions on IR sequence scans. On SE sequence, the subcortical white matter was imaged as a brighter area than the cerebral cortex. These results demonstrate that the degree of myelination in these patients was roughly equal to that of 3-to 6-month old infants.

  12. Distribution of somatostatin immunoreactive products in the brain stem auditory center of guinea pigs%豚鼠脑干听觉中枢生长抑素免疫反应产物的分布

    Institute of Scientific and Technical Information of China (English)

    王唯析; 赵明光; 胡海涛; 许珉; 马惠芳; 任惠民

    2000-01-01

    Objective To research the distribution and significance of somatostatin(SS) in the brain stem auditory centre of guinea pigs. Methods The distribution of SS positive products in the cochlear nucleus(CN), superior olivary complex(SOC) and the inferior colliculus(IC) of the brain stem auditory centre of guinea pigs was investigated with immunohistochemical ABC method.Results The SS positive neurons, fibers and terminals were widely distributed in the brain stem auditory center. The SS positive neurons were mainly distributed in the ventral cochlear nucleus (VCN), nucleus of the trapezoid body(NTB), medial superior olive(MSO) and paraolivary nucleus (PON). The high density of SS-immunoreactive fibers and terminals was observed in the nucleus of IC, lateral superior olive(LSO) and dorsal cochlear nucleus(DCN). Conclusion The SS may participate in transmitting and regulating sound messages in brain stem auditory center of guinea pigs.%目的研究生长抑素(SS)在豚鼠脑干听觉中枢的分布及意义。方法采用免疫组化ABC法观察了豚鼠脑干听觉中枢的耳蜗核(CN)、上橄榄核簇(SOC)及下丘(IC)内SS免疫反应阳性产物的分布。结果在脑干听觉中枢广泛分布着SS阳性神经元、纤维及终末。SS阳性神经元主要分布在蜗神经腹核(VCN)、斜方体核(NTB)、内侧上橄榄核(MSO)及橄榄周核(PON),而SS阳性纤维及终末主要分布在下丘、外侧上橄榄核(LSO)及蜗神经背核(DCN)。结论脑干听觉中枢内的SS参与声信号的传递与调控。

  13. Modeling of Auditory Neuron Response Thresholds with Cochlear Implants

    Directory of Open Access Journals (Sweden)

    Frederic Venail

    2015-01-01

    Full Text Available The quality of the prosthetic-neural interface is a critical point for cochlear implant efficiency. It depends not only on technical and anatomical factors such as electrode position into the cochlea (depth and scalar placement, electrode impedance, and distance between the electrode and the stimulated auditory neurons, but also on the number of functional auditory neurons. The efficiency of electrical stimulation can be assessed by the measurement of e-CAP in cochlear implant users. In the present study, we modeled the activation of auditory neurons in cochlear implant recipients (nucleus device. The electrical response, measured using auto-NRT (neural responses telemetry algorithm, has been analyzed using multivariate regression with cubic splines in order to take into account the variations of insertion depth of electrodes amongst subjects as well as the other technical and anatomical factors listed above. NRT thresholds depend on the electrode squared impedance (β = −0.11 ± 0.02, P<0.01, the scalar placement of the electrodes (β = −8.50 ± 1.97, P<0.01, and the depth of insertion calculated as the characteristic frequency of auditory neurons (CNF. Distribution of NRT residues according to CNF could provide a proxy of auditory neurons functioning in implanted cochleas.

  14. Modeling of Auditory Neuron Response Thresholds with Cochlear Implants.

    Science.gov (United States)

    Venail, Frederic; Mura, Thibault; Akkari, Mohamed; Mathiolon, Caroline; Menjot de Champfleur, Sophie; Piron, Jean Pierre; Sicard, Marielle; Sterkers-Artieres, Françoise; Mondain, Michel; Uziel, Alain

    2015-01-01

    The quality of the prosthetic-neural interface is a critical point for cochlear implant efficiency. It depends not only on technical and anatomical factors such as electrode position into the cochlea (depth and scalar placement), electrode impedance, and distance between the electrode and the stimulated auditory neurons, but also on the number of functional auditory neurons. The efficiency of electrical stimulation can be assessed by the measurement of e-CAP in cochlear implant users. In the present study, we modeled the activation of auditory neurons in cochlear implant recipients (nucleus device). The electrical response, measured using auto-NRT (neural responses telemetry) algorithm, has been analyzed using multivariate regression with cubic splines in order to take into account the variations of insertion depth of electrodes amongst subjects as well as the other technical and anatomical factors listed above. NRT thresholds depend on the electrode squared impedance (β = -0.11 ± 0.02, P < 0.01), the scalar placement of the electrodes (β = -8.50 ± 1.97, P < 0.01), and the depth of insertion calculated as the characteristic frequency of auditory neurons (CNF). Distribution of NRT residues according to CNF could provide a proxy of auditory neurons functioning in implanted cochleas.

  15. A new method for piercing the tentorium cerebelli for implanting fragile electrodes into the brain stem in the rhesus monkey (Macaca mulatta).

    Science.gov (United States)

    Wu, Jing; Wang, Wenchao; Rizak, Joshua Dominic; Wang, Zhengbo; Wang, Jianhong; Feng, Xiaoli; Dong, Jinrun; Li, Lin; Liu, Li; Xu, Liqi; Yang, Shangchuan; Hu, Xintian

    2014-03-01

    Recent developments in neuron recording techniques include the invention of some fragile electrodes. The fragility of these electrodes impedes their successful use in deep brain recordings because it is difficult to penetrate the electrodes through the dura mater, especially the tentorium cerebelli (TC) enclosing the cerebellum and brain stem. This paper reports a new method to pierce the TC for inserting fragile electrodes into the inferior colliculus of rhesus monkeys. Briefly, a unique tool kit, consisting of needles with sharp tips, a guide tube and an "impactor," was used in a multistep protocol to pierce the TC. The impactor provided a brief force that quickly thrusts the needles through the meninges without causing significant damage to the brain tissue under the TC. Using this novel approach, tetrodes were successfully implanted into the inferior colliculus of a rhesus monkey and neuronal discharge signals were recorded. This method, which is simple, convenient and economical, allows neurophysiologists to study the electrophysiological characteristics of deep brain structures under the TC with advanced, albeit fragile, electrodes.

  16. Benefits and detriments of unilateral cochlear implant use on bilateral auditory development in children who are deaf

    Directory of Open Access Journals (Sweden)

    Karen A. Gordon

    2013-10-01

    Full Text Available We have explored both the benefits and detriments of providing electrical input through a cochlear implant in one ear to the auditory system of young children. A cochlear implant delivers electrical pulses to stimulate the auditory nerve, providing children who are deaf with access to sound. The goals of implantation are to restrict reorganization of the deprived immature auditory brain and promote development of hearing and spoken language. It is clear that limiting the duration of deprivation is a key factor. Additional considerations are the onset, etiology, and use of residual hearing as each of these can have unique effects on auditory development in the pre-implant period. New findings show that many children receiving unilateral cochlear implants are developing mature-like brainstem and thalamo-cortical responses to sound with long term use despite these sources of variability; however, there remain considerable abnormalities in cortical function. The most apparent, determined by implanting the other ear and measuring responses to acute stimulation, is a loss of normal cortical response from the deprived ear. Recent data reveal that this can be avoided in children by early implantation of both ears simultaneously or with limited delay. We conclude that auditory development requires input early in development and from both ears.

  17. The effect of gender on bone-conduct auditory brain stem response%性别对骨导听性脑干反应的影响

    Institute of Scientific and Technical Information of China (English)

    窦晓宁; 徐荣华; 任雪莲; 王爱婷; 杨燕燕; 张敏敏

    2014-01-01

    Objective To study the difference of bone‐conduct auditory brain stem response (ABR) results between different genders and to provide reference for clinical practice .Methods Bone‐oscillatory is placed on the mastoid portion ,back of the ear and the frontal placement in a group of normal hearing adults .The results of air and bone‐conduct ABR were recorded and analyzed .Results There were no differences for the threshold of air‐conduct and bone‐conduct ABR testing in different placements ( P>0 .05) .Under 30 dBnHL above the threshold , there were no differences forⅠ ,Ⅲ peak latency (PL) of air‐conduct and bone‐conduct ABR between gender( P>0 .05) .There were differences forⅤPL ( P0 .05) .There were differences forⅠ‐ⅤIPL( P<0 .05) . Conclusion There were differences forⅤPL ,Ⅰ‐ⅤIPL of air‐conduct and bone‐conduct ABR between genders .So we should consider the difference of the gender and have normal reference value of different genders.%目的:研究不同性别间骨导听性脑干反应(ABR)结果间的差异性。方法选择听力正常成年人60名(120耳),男性及女性各30名(60耳),将骨导 ABR的振荡器分别放置乳突、耳后、额部,进行骨、气导ABR检测,对检测结果进行性别间比较分析。结果气导及各部位骨导ABR阈值性别间比较,差异无统计学意义( P>0.05)。在阈上30 dBnHL刺激强度下,各部位骨导与气导ABRⅠ、Ⅲ波峰潜伏期(PL)性别间比较,差异均无统计学意义( P >0.05)。各部位骨导与气导ABRⅤ波PL性别间比较,差异均有统计学意义( P <0.05)。气导与各部位骨导Ⅰ~Ⅲ波峰间期(IPL )性别间比较,差异均无统计学意义( P >0.05)。气导与各部位骨导Ⅰ~ⅤIPL性别间比较,差异均有统计学意义( P <0.05)。结论不同性别间骨、气导ABRⅤ波PL及Ⅰ ~ⅤIPL存在差异性,检测时应充分考虑到性别间

  18. Auditory Rehabilitation in Rhesus Macaque Monkeys (Macaca mulatta) with Auditory Brainstem Implants

    Institute of Scientific and Technical Information of China (English)

    Zhen-Min Wang; Zhi-Jun Yang; Fu Zhao; Bo Wang; Xing-Chao Wang; Pei-Ran Qu; Pi-Nan Liu

    2015-01-01

    Background:The auditory brainstem implants (ABIs) have been used to treat deafness for patients with neurofibromatosis Type 2 and nontumor patients.The lack of an appropriate animal model has limited the study of improving hearing rehabilitation by the device.This study aimed to establish an animal model of ABI in adult rhesus macaque monkey (Macaca mulatta).Methods:Six adult rhesus macaque monkeys (M.mulatta) were included.Under general anesthesia,a multichannel ABI was implanted into the lateral recess of the fourth ventricle through the modified suboccipital-retrosigmoid (RS) approach.The electrical auditory brainstem response (EABR) waves were tested to ensure the optimal implant site.After the operation,the EABR and computed tomography (CT) were used to test and verify the effectiveness via electrophysiology and anatomy,respectively.The subjects underwent behavioral observation for 6 months,and the postoperative EABR was tested every two weeks from the 1st month after implant surgery.Result:The implant surgery lasted an average of 5.2 h,and no monkey died or sacrificed.The averaged latencies of peaks Ⅰ,Ⅱ and Ⅳ were 1.27,2.34 and 3.98 ms,respectively in the ABR.One-peak EABR wave was elicited in the operation,and one-or two-peak waves were elicited during the postoperative period.The EABR wave latencies appeared to be constant under different stimulus intensities;however,the amplitudes increased as the stimulus increased within a certain scope.Conclusions:It is feasible and safe to implant ABIs in rhesus macaque monkeys (M.mulatta) through a modified suboccipital RS approach,and EABR and CT are valid tools for animal model establishment.In addition,this model should be an appropriate animal model for the electrophysiological and behavioral study of rhesus macaque monkey with ABI.

  19. Comparison of Auditory Perception in Cochlear Implanted Children with and without Additional Disabilities

    Directory of Open Access Journals (Sweden)

    Seyed Basir Hashemi

    2016-05-01

    Full Text Available Background: The number of children with cochlear implants who have other difficulties such as attention deficiency and cerebral palsy has increased dramatically. Despite the need for information on the results of cochlear implantation in this group, the available literature is extremely limited. We, therefore, sought to compare the levels of auditory perception in children with cochlear implants with and without additional disabilities. Methods: A spondee test comprising 20 two-syllable words was performed. The data analysis was done using SPSS, version 19. Results: Thirty-one children who had received cochlear implants 2 years previously and were at an average age of 7.5 years were compared via the spondee test. From the 31 children,15 had one or more additional disabilities. The data analysis indicated that the mean score of auditory perception in this group was approximately 30 scores below that of the children with cochlear implants who had no additional disabilities. Conclusion: Although there was an improvement in the auditory perception of all the children with cochlear implants, there was a noticeable difference in the level of auditory perception between those with and without additional disabilities. Deafness and additional disabilities depended the children on lip reading alongside the auditory ways of communication. In addition, the level of auditory perception in the children with cochlear implants who had more than one additional disability was significantly less than that of the other children with cochlear implants who had one additional disability.

  20. Intracerebral neural stem cell transplantation improved the auditory of mice with presbycusis.

    Science.gov (United States)

    Ren, Hongmiao; Chen, Jichuan; Wang, Yinan; Zhang, Shichang; Zhang, Bo

    2013-01-01

    Stem cell-based regenerative therapy is a potential cellular therapeutic strategy for patients with incurable brain diseases. Embryonic neural stem cells (NSCs) represent an attractive cell source in regenerative medicine strategies in the treatment of diseased brains. Here, we assess the capability of intracerebral embryonic NSCs transplantation for C57BL/6J mice with presbycusis in vivo. Morphology analyses revealed that the neuronal rate of apoptosis was lower in the aged group (10 months of age) but not in the young group (2 months of age) after NSCs transplantation, while the electrophysiological data suggest that the Auditory Brain Stem Response (ABR) threshold was significantly decreased in the aged group at 2 weeks and 3 weeks after transplantation. By contrast, there was no difference in the aged group at 4 weeks post-transplantation or in the young group at any time post-transplantation. Furthermore, immunofluorescence experiments showed that NSCs differentiated into neurons that engrafted and migrated to the brain, even to sites of lesions. Together, our results demonstrate that NSCs transplantation improve the auditory of C57BL/6J mice with presbycusis.

  1. Auditory distraction transmitted by a cochlear implant alters allocation of attentional resources

    Directory of Open Access Journals (Sweden)

    Mareike eFinke

    2015-03-01

    Full Text Available Cochlear implants (CIs are auditory prostheses which restore hearing via electrical stimulation of the auditory nerve. The successful adaptation of auditory cognition to the CI input depends to a substantial degree on individual factors. We pursued an electrophysiological approach towards an analysis of cortical responses that reflect perceptual processing stages and higher-level responses to CI input. Performance and event-related potentials on two cross-modal discrimination-following-distraction tasks from CI users and normal-hearing (NH individuals were compared. The visual-auditory distraction task combined visual distraction with following auditory discrimination performance. Here, we observed similar cortical responses to visual distractors (Novelty-N2 and slowed, less accurate auditory discrimination performance in CI users when compared to NH individuals. Conversely, the auditory-visual distraction task was used to combine auditory distraction with visual discrimination performance. In this task we found attenuated cortical responses to auditory distractors (Novelty-P3, slowed visual discrimination performance, and attenuated cortical P3-responses to visual targets in CI users compared to NH individuals. These results suggest that CI users process auditory distractors differently than NH individuals and that the presence of auditory CI input has an adverse effect on the processing of visual targets and the visual discrimination ability in implanted individuals. We propose that this attenuation of the visual modality occurs through the allocation of neural resources to the CI input.

  2. Horseradish peroxidase dye tracing and embryonic statoacoustic ganglion cell transplantation in the rat auditory nerve trunk.

    Science.gov (United States)

    Palmgren, Björn; Jin, Zhe; Jiao, Yu; Kostyszyn, Beata; Olivius, Petri

    2011-03-04

    At present severe damage to hair cells and sensory neurons in the inner ear results in non-treatable auditory disorders. Cell implantation is a potential treatment for various neurological disorders and has already been used in clinical practice. In the inner ear, delivery of therapeutic substances including neurotrophic factors and stem cells provide strategies that in the future may ameliorate or restore hearing impairment. In order to describe a surgical auditory nerve trunk approach, in the present paper we injected the neuronal tracer horseradish peroxidase (HRP) into the central part of the nerve by an intra cranial approach. We further evaluated the applicability of the present approach by implanting statoacoustic ganglion (SAG) cells into the same location of the auditory nerve in normal hearing rats or animals deafened by application of β-bungarotoxin to the round window niche. The HRP results illustrate labeling in the cochlear nucleus in the brain stem as well as peripherally in the spiral ganglion neurons in the cochlea. The transplanted SAGs were observed within the auditory nerve trunk but no more peripheral than the CNS-PNS transitional zone. Interestingly, the auditory nerve injection did not impair auditory function, as evidenced by the auditory brainstem response. The present findings illustrate that an auditory nerve trunk approach may well access the entire auditory nerve and does not compromise auditory function. We suggest that such an approach might compose a suitable route for cell transplantation into this sensory cranial nerve.

  3. Cooperative dynamics in auditory brain response

    CERN Document Server

    Kwapien, J; Liu, L C; Ioannides, A A

    1998-01-01

    Simultaneous estimates of the activity in the left and right auditory cortex of five normal human subjects were extracted from Multichannel Magnetoencephalography recordings. Left, right and binaural stimulation were used, in separate runs, for each subject. The resulting time-series of left and right auditory cortex activity were analysed using the concept of mutual information. The analysis constitutes an objective method to address the nature of inter-hemispheric correlations in response to auditory stimulations. The results provide a clear evidence for the occurrence of such correlations mediated by a direct information transport, with clear laterality effects: as a rule, the contralateral hemisphere leads by 10-20ms, as can be seen in the average signal. The strength of the inter-hemispheric coupling, which cannot be extracted from the average data, is found to be highly variable from subject to subject, but remarkably stable for each subject.

  4. [Analysis of auditory information in the brain of the cetacean].

    Science.gov (United States)

    Popov, V V; Supin, A Ia

    2006-01-01

    The cetacean brain specifics involve an exceptional development of the auditory neural centres. The place of projection sensory areas including the auditory that in the cetacean brain cortex is essentially different from that in other mammals. The EP characteristics indicated presence of several functional divisions in the auditory cortex. Physiological studies of the cetacean auditory centres were mainly performed using the EP technique. Of several types of the EPs, the short-latency auditory EP was most thoroughly studied. In cetacean, it is characterised by exceptionally high temporal resolution with the integration time about 0.3 ms which corresponds to the cut-off frequency 1700 Hz. This much exceeds the temporal resolution of the hearing in terranstrial mammals. The frequency selectivity of hearing in cetacean was measured using a number of variants of the masking technique. The hearing frequency selectivity acuity in cetacean exceeds that of most terraneous mammals (excepting the bats). This acute frequency selectivity provides the differentiation among the finest spectral patterns of auditory signals.

  5. Music and the auditory brain: where is the connection?

    Directory of Open Access Journals (Sweden)

    Israel eNelken

    2011-09-01

    Full Text Available Sound processing by the auditory system is understood in unprecedented details, even compared with sensory coding in the visual system. Nevertheless, we don't understand yet the way in which some of the simplest perceptual properties of sounds are coded in neuronal activity. This poses serious difficulties for linking neuronal responses in the auditory system and music processing, since music operates on abstract representations of sounds. Paradoxically, although perceptual representations of sounds most probably occur high in auditory system or even beyond it, neuronal responses are strongly affected by the temporal organization of sound streams even in subcortical stations. Thus, to the extent that music is organized sound, it is the organization, rather than the sound, which is represented first in the auditory brain.

  6. Shaping the aging brain: Role of auditory input patterns in the emergence of auditory cortical impairments

    Directory of Open Access Journals (Sweden)

    Brishna Soraya Kamal

    2013-09-01

    Full Text Available Age-related impairments in the primary auditory cortex (A1 include poor tuning selectivity, neural desynchronization and degraded responses to low-probability sounds. These changes have been largely attributed to reduced inhibition in the aged brain, and are thought to contribute to substantial hearing impairment in both humans and animals. Since many of these changes can be partially reversed with auditory training, it has been speculated that they might not be purely degenerative, but might rather represent negative plastic adjustments to noisy or distorted auditory signals reaching the brain. To test this hypothesis, we examined the impact of exposing young adult rats to 8 weeks of low-grade broadband noise on several aspects of A1 function and structure. We then characterized the same A1 elements in aging rats for comparison. We found that the impact of noise exposure on A1 tuning selectivity, temporal processing of auditory signal and responses to oddball tones was almost indistinguishable from the effect of natural aging. Moreover, noise exposure resulted in a reduction in the population of parvalbumin inhibitory interneurons and cortical myelin as previously documented in the aged group. Most of these changes reversed after returning the rats to a quiet environment. These results support the hypothesis that age-related changes in A1 have a strong activity-dependent component and indicate that the presence or absence of clear auditory input patterns might be a key factor in sustaining adult A1 function.

  7. Auditory cortical activity during cochlear implant-mediated perception of spoken language, melody, and rhythm.

    Science.gov (United States)

    Limb, Charles J; Molloy, Anne T; Jiradejvong, Patpong; Braun, Allen R

    2010-03-01

    Despite the significant advances in language perception for cochlear implant (CI) recipients, music perception continues to be a major challenge for implant-mediated listening. Our understanding of the neural mechanisms that underlie successful implant listening remains limited. To our knowledge, this study represents the first neuroimaging investigation of music perception in CI users, with the hypothesis that CI subjects would demonstrate greater auditory cortical activation than normal hearing controls. H(2) (15)O positron emission tomography (PET) was used here to assess auditory cortical activation patterns in ten postlingually deafened CI patients and ten normal hearing control subjects. Subjects were presented with language, melody, and rhythm tasks during scanning. Our results show significant auditory cortical activation in implant subjects in comparison to control subjects for language, melody, and rhythm. The greatest activity in CI users compared to controls was seen for language tasks, which is thought to reflect both implant and neural specializations for language processing. For musical stimuli, PET scanning revealed significantly greater activation during rhythm perception in CI subjects (compared to control subjects), and the least activation during melody perception, which was the most difficult task for CI users. These results may suggest a possible relationship between auditory performance and degree of auditory cortical activation in implant recipients that deserves further study.

  8. Electric auditory brainstem response (E-ABR in cochlear implant children: Effect of age at implantation and duration of implant use

    Directory of Open Access Journals (Sweden)

    Nithreen Mohammed Said Abdelsalam

    2015-07-01

    Conclusion: A well-established EABR was obtained in cochlear implant children with proper parameters. The characterizations of the EABR waves including wave latencies and threshold were extracted at different electrodes. The EABR test proves to be an effective method to evaluate the functions of the auditory pathway in children after cochlear implantation.

  9. Auditory midbrain implant: research and development towards a second clinical trial.

    Science.gov (United States)

    Lim, Hubert H; Lenarz, Thomas

    2015-04-01

    The cochlear implant is considered one of the most successful neural prostheses to date, which was made possible by visionaries who continued to develop the cochlear implant through multiple technological and clinical challenges. However, patients without a functional auditory nerve or implantable cochlea cannot benefit from a cochlear implant. The focus of the paper is to review the development and translation of a new type of central auditory prosthesis for this group of patients that is known as the auditory midbrain implant (AMI) and is designed for electrical stimulation within the inferior colliculus. The rationale and results for the first AMI clinical study using a multi-site single-shank array will be presented initially. Although the AMI has achieved encouraging results in terms of safety and improvements in lip-reading capabilities and environmental awareness, it has not yet provided sufficient speech perception. Animal and human data will then be presented to show that a two-shank AMI array can potentially improve hearing performance by targeting specific neurons of the inferior colliculus. A new two-shank array, stimulation strategy, and surgical approach are planned for the AMI that are expected to improve hearing performance in the patients who will be implanted in an upcoming clinical trial funded by the National Institutes of Health. Positive outcomes from this clinical trial will motivate new efforts and developments toward improving central auditory prostheses for those who cannot sufficiently benefit from cochlear implants. This article is part of a Special Issue entitled .

  10. Experiences from Cochlear Implantation and Auditory Brainstem Implantation in Adults and Children : Electrophysiological Measurements, Hearing Outcomes and Patient Satisfaction

    OpenAIRE

    Lundin, Karin

    2016-01-01

    Cochlear implants (CIs) and auditory brainstem implants (ABIs) are prostheses for hearing used in patients with profound hearing impairment. A CI requires an operational cochlear nerve to function in contrast to an ABI. ABIs were initially designed for adult patients with neurofibromatosis type 2 (NF2), suffering from bilateral vestibular schwannomas. Now ABIs are also used for patients, both adults and children, with congenital cochlear malformations, cochlear nerve hypoplasia/aplasia, and c...

  11. Thalamic and parietal brain morphology predicts auditory category learning.

    Science.gov (United States)

    Scharinger, Mathias; Henry, Molly J; Erb, Julia; Meyer, Lars; Obleser, Jonas

    2014-01-01

    Auditory categorization is a vital skill involving the attribution of meaning to acoustic events, engaging domain-specific (i.e., auditory) as well as domain-general (e.g., executive) brain networks. A listener's ability to categorize novel acoustic stimuli should therefore depend on both, with the domain-general network being particularly relevant for adaptively changing listening strategies and directing attention to relevant acoustic cues. Here we assessed adaptive listening behavior, using complex acoustic stimuli with an initially salient (but later degraded) spectral cue and a secondary, duration cue that remained nondegraded. We employed voxel-based morphometry (VBM) to identify cortical and subcortical brain structures whose individual neuroanatomy predicted task performance and the ability to optimally switch to making use of temporal cues after spectral degradation. Behavioral listening strategies were assessed by logistic regression and revealed mainly strategy switches in the expected direction, with considerable individual differences. Gray-matter probability in the left inferior parietal lobule (BA 40) and left precentral gyrus was predictive of "optimal" strategy switch, while gray-matter probability in thalamic areas, comprising the medial geniculate body, co-varied with overall performance. Taken together, our findings suggest that successful auditory categorization relies on domain-specific neural circuits in the ascending auditory pathway, while adaptive listening behavior depends more on brain structure in parietal cortex, enabling the (re)direction of attention to salient stimulus properties.

  12. Auditory and Visual Electrophysiology of Deaf Children with Cochlear Implants: Implications for Cross-modal Plasticity.

    Science.gov (United States)

    Corina, David P; Blau, Shane; LaMarr, Todd; Lawyer, Laurel A; Coffey-Corina, Sharon

    2017-01-01

    Deaf children who receive a cochlear implant early in life and engage in intensive oral/aural therapy often make great strides in spoken language acquisition. However, despite clinicians' best efforts, there is a great deal of variability in language outcomes. One concern is that cortical regions which normally support auditory processing may become reorganized for visual function, leaving fewer available resources for auditory language acquisition. The conditions under which these changes occur are not well understood, but we may begin investigating this phenomenon by looking for interactions between auditory and visual evoked cortical potentials in deaf children. If children with abnormal auditory responses show increased sensitivity to visual stimuli, this may indicate the presence of maladaptive cortical plasticity. We recorded evoked potentials, using both auditory and visual paradigms, from 25 typical hearing children and 26 deaf children (ages 2-8 years) with cochlear implants. An auditory oddball paradigm was used (85% /ba/ syllables vs. 15% frequency modulated tone sweeps) to elicit an auditory P1 component. Visual evoked potentials (VEPs) were recorded during presentation of an intermittent peripheral radial checkerboard while children watched a silent cartoon, eliciting a P1-N1 response. We observed reduced auditory P1 amplitudes and a lack of latency shift associated with normative aging in our deaf sample. We also observed shorter latencies in N1 VEPs to visual stimulus offset in deaf participants. While these data demonstrate cortical changes associated with auditory deprivation, we did not find evidence for a relationship between cortical auditory evoked potentials and the VEPs. This is consistent with descriptions of intra-modal plasticity within visual systems of deaf children, but do not provide evidence for cross-modal plasticity. In addition, we note that sign language experience had no effect on deaf children's early auditory and visual ERP

  13. Auditory and Visual Electrophysiology of Deaf Children with Cochlear Implants: Implications for Cross-modal Plasticity

    Science.gov (United States)

    Corina, David P.; Blau, Shane; LaMarr, Todd; Lawyer, Laurel A.; Coffey-Corina, Sharon

    2017-01-01

    Deaf children who receive a cochlear implant early in life and engage in intensive oral/aural therapy often make great strides in spoken language acquisition. However, despite clinicians’ best efforts, there is a great deal of variability in language outcomes. One concern is that cortical regions which normally support auditory processing may become reorganized for visual function, leaving fewer available resources for auditory language acquisition. The conditions under which these changes occur are not well understood, but we may begin investigating this phenomenon by looking for interactions between auditory and visual evoked cortical potentials in deaf children. If children with abnormal auditory responses show increased sensitivity to visual stimuli, this may indicate the presence of maladaptive cortical plasticity. We recorded evoked potentials, using both auditory and visual paradigms, from 25 typical hearing children and 26 deaf children (ages 2–8 years) with cochlear implants. An auditory oddball paradigm was used (85% /ba/ syllables vs. 15% frequency modulated tone sweeps) to elicit an auditory P1 component. Visual evoked potentials (VEPs) were recorded during presentation of an intermittent peripheral radial checkerboard while children watched a silent cartoon, eliciting a P1–N1 response. We observed reduced auditory P1 amplitudes and a lack of latency shift associated with normative aging in our deaf sample. We also observed shorter latencies in N1 VEPs to visual stimulus offset in deaf participants. While these data demonstrate cortical changes associated with auditory deprivation, we did not find evidence for a relationship between cortical auditory evoked potentials and the VEPs. This is consistent with descriptions of intra-modal plasticity within visual systems of deaf children, but do not provide evidence for cross-modal plasticity. In addition, we note that sign language experience had no effect on deaf children’s early auditory and visual

  14. Role of auditory feedback in speech produced by cochlear implanted adults and children

    Science.gov (United States)

    Bharadwaj, Sneha V.; Tobey, Emily A.; Assmann, Peter F.; Katz, William F.

    2002-05-01

    A prominent theory of speech production proposes that speech segments are largely controlled by reference to an internal model, with minimal reliance on auditory feedback. This theory also maintains that suprasegmental aspects of speech are directly regulated by auditory feedback. Accordingly, if a talker is briefly deprived of auditory feedback speech segments should not be affected, but suprasegmental properties should show significant change. To test this prediction, comparisons were made between speech samples obtained from cochlear implant users who repeated words under two conditions (1) implant device turned ON, and (2) implant switched OFF immediately before the repetition of each word. To determine whether producing unfamiliar speech requires greater reliance on auditory feedback than producing familiar speech, English and French words were elicited from English-speaking subjects. Subjects were congenitally deaf children (n=4) and adventitiously deafened adults (n=4). Vowel fundamental frequency and formant frequencies, vowel and syllable durations, and fricative spectral moments were analyzed. Preliminary data only partially confirm the predictions, in that both segmental and suprasegmental aspects of speech were significantly modified in the absence of auditory feedback. Modifications were greater for French compared to English words, suggesting greater reliance on auditory feedback for unfamiliar words. [Work supported by NIDCD.

  15. Neural stem cells intravenous implantation improves the neurological function of mice after traumatic brain injury%神经干细胞移植显著改善脑外伤小鼠的神经功能

    Institute of Scientific and Technical Information of China (English)

    仇波; 王勇; 吴鹏飞; 秦晓飞; 王运杰

    2012-01-01

    目的 探讨鼠源性神经干细胞( neural stem cells,NSCs)静脉移植对脑外伤小鼠海马的治疗作用.方法 30只BALB/c小鼠随机分为3组,假手术组(10只)、脑外伤组(10只)和NSCs移植组(10只).NSCs移植7d后,根据小鼠脑损伤NSS(Neurological Severity Score)评分系统进行评分.TUNEL法检测各组小鼠海马细胞凋亡情况.免疫组化和Western blot检测各组小鼠海马半胱氨酸蛋白酶-3(cysteinyl aspirate specificproteinase3,caspase-3)蛋白的表达.结果 NSCs移植7d后,NSS评分显示NSCs移植组的神经功能明显改善(P<0.001).TUNEL法检测结果发现,脑外伤组小鼠海马凋亡细胞百分数明显高于假手术组(P<0.05),但经过NSCs移植后,凋亡率显著下降.免疫组化和Western blot结果显示,脑外伤组小鼠海马caspase-3蛋白表达量明显高于假手术组(P<0.05),但NSCs移植组小鼠海马caspase-3表达明显降低(P<0.05).结论 静脉NSCs移植能够显著改善脑外伤小鼠的神经功能,其机制可能与降低caspase-3的表达有关.%Objective To study the effect of neural stem cells(NSCs)intravenous implantation on neurological function of mice after traumatic brain injury. Methods 30 BALB/c mice were randomly divided into the sham group(10, S group), traumatic brain injury group(10, T group)and NSCs implantation group (10, N group). The neurufuiiclion of mice was scored by NSS scoring system. The apoptotic hippocampus cells of all groups were stained using TUNEL assay, and expression levels of caspase-3 in hippocampus of all groups were examined by immunohistochemistry and Western blot. Results After NSCs implantation, neurological function of N group mice evaluated by Neurological Severity Score(NSS)was significantly improved compared to T group (P<0.00l). The percentages of apoptotic hippocampal cells increased significantly in T group compared to S group, and decreased after NSCs implantation (P<0.05). The expression levels of caspase-3 in hippocampus

  16. Infant Auditory Processing and Event-related Brain Oscillations

    Science.gov (United States)

    Musacchia, Gabriella; Ortiz-Mantilla, Silvia; Realpe-Bonilla, Teresa; Roesler, Cynthia P.; Benasich, April A.

    2015-01-01

    Rapid auditory processing and acoustic change detection abilities play a critical role in allowing human infants to efficiently process the fine spectral and temporal changes that are characteristic of human language. These abilities lay the foundation for effective language acquisition; allowing infants to hone in on the sounds of their native language. Invasive procedures in animals and scalp-recorded potentials from human adults suggest that simultaneous, rhythmic activity (oscillations) between and within brain regions are fundamental to sensory development; determining the resolution with which incoming stimuli are parsed. At this time, little is known about oscillatory dynamics in human infant development. However, animal neurophysiology and adult EEG data provide the basis for a strong hypothesis that rapid auditory processing in infants is mediated by oscillatory synchrony in discrete frequency bands. In order to investigate this, 128-channel, high-density EEG responses of 4-month old infants to frequency change in tone pairs, presented in two rate conditions (Rapid: 70 msec ISI and Control: 300 msec ISI) were examined. To determine the frequency band and magnitude of activity, auditory evoked response averages were first co-registered with age-appropriate brain templates. Next, the principal components of the response were identified and localized using a two-dipole model of brain activity. Single-trial analysis of oscillatory power showed a robust index of frequency change processing in bursts of Theta band (3 - 8 Hz) activity in both right and left auditory cortices, with left activation more prominent in the Rapid condition. These methods have produced data that are not only some of the first reported evoked oscillations analyses in infants, but are also, importantly, the product of a well-established method of recording and analyzing clean, meticulously collected, infant EEG and ERPs. In this article, we describe our method for infant EEG net

  17. Sex differences in brain structure in auditory and cingulate regions

    OpenAIRE

    Brun, Caroline C.; Lepore, Natasha; Luders, Eileen; Chou, Yi-Yu; Madsen, Sarah K.; Toga, Arthur W; Thompson, Paul M.

    2009-01-01

    We applied a new method to visualize the three-dimensional profile of sex differences in brain structure based on MRI scans of 100 young adults. We compared 50 men with 50 women, matched for age and other relevant demographics. As predicted, left hemisphere auditory and language-related regions were proportionally expanded in women versus men, suggesting a possible structural basis for the widely replicated sex differences in language processing. In men, primary visual, and visuo-spatial asso...

  18. Auditory Cortical Maturation in a Child with Cochlear Implant: Analysis of Electrophysiological and Behavioral Measures

    Science.gov (United States)

    Silva, Liliane Aparecida Fagundes; Couto, Maria Inês Vieira; Tsuji, Robinson Koji; Bento, Ricardo Ferreira; de Carvalho, Ana Claudia Martinho; Matas, Carla Gentile

    2015-01-01

    The purpose of this study was to longitudinally assess the behavioral and electrophysiological hearing changes of a girl inserted in a CI program, who had bilateral profound sensorineural hearing loss and underwent surgery of cochlear implantation with electrode activation at 21 months of age. She was evaluated using the P1 component of Long Latency Auditory Evoked Potential (LLAEP); speech perception tests of the Glendonald Auditory Screening Procedure (GASP); Infant Toddler Meaningful Auditory Integration Scale (IT-MAIS); and Meaningful Use of Speech Scales (MUSS). The study was conducted prior to activation and after three, nine, and 18 months of cochlear implant activation. The results of the LLAEP were compared with data from a hearing child matched by gender and chronological age. The results of the LLAEP of the child with cochlear implant showed gradual decrease in latency of the P1 component after auditory stimulation (172 ms–134 ms). In the GASP, IT-MAIS, and MUSS, gradual development of listening skills and oral language was observed. The values of the LLAEP of the hearing child were expected for chronological age (132 ms–128 ms). The use of different clinical instruments allow a better understanding of the auditory habilitation and rehabilitation process via CI. PMID:26881163

  19. Auditory and oral language abilities in children with cochlear implants: a case study.

    Science.gov (United States)

    Melo, Tatiana Mendes de; Lara, Jessica Domingues

    2012-01-01

    The cochlear implant (CI) represents the most important advance in the treatment of individuals with severe to profound bilateral hearing loss who do not benefit from hearing aids. Children who receive the CI during the critical period of neuroplasticity of the auditory system, when combined with speech therapy, have the chance to develop the auditory and linguistic skills similarly to their normal hearing peers. Two cases of implanted children are presented in this study, and one of them was not enrolled in a formal aurioral therapeutic program since the implantation surgery. At the moment of language and auditory assessment, the children were 2 years and 5 months old, and the CI had been used for 11 months. According to the results presented, it was observed that the child enrolled in rehabilitation program had better auditory and language performance when compared to the other child. Despite the remarkable benefits that the CI provides to children with hearing impairment, the device itself only provides the child with the audibility of environmental sounds and speech signal. For the auditory and language development to happen, it is necessary, among other factors, a speech-language intervention, with partnership between professionals and parents.

  20. Auditory Cortical Maturation in a Child with Cochlear Implant: Analysis of Electrophysiological and Behavioral Measures

    Directory of Open Access Journals (Sweden)

    Liliane Aparecida Fagundes Silva

    2015-01-01

    Full Text Available The purpose of this study was to longitudinally assess the behavioral and electrophysiological hearing changes of a girl inserted in a CI program, who had bilateral profound sensorineural hearing loss and underwent surgery of cochlear implantation with electrode activation at 21 months of age. She was evaluated using the P1 component of Long Latency Auditory Evoked Potential (LLAEP; speech perception tests of the Glendonald Auditory Screening Procedure (GASP; Infant Toddler Meaningful Auditory Integration Scale (IT-MAIS; and Meaningful Use of Speech Scales (MUSS. The study was conducted prior to activation and after three, nine, and 18 months of cochlear implant activation. The results of the LLAEP were compared with data from a hearing child matched by gender and chronological age. The results of the LLAEP of the child with cochlear implant showed gradual decrease in latency of the P1 component after auditory stimulation (172 ms–134 ms. In the GASP, IT-MAIS, and MUSS, gradual development of listening skills and oral language was observed. The values of the LLAEP of the hearing child were expected for chronological age (132 ms–128 ms. The use of different clinical instruments allow a better understanding of the auditory habilitation and rehabilitation process via CI.

  1. Brain response to a rhythm deviant in adolescent cochlear implant users before and after an intensive musical training program

    DEFF Research Database (Denmark)

    Petersen, Bjørn; Weed, Ethan; Hansen, Mads

    . This study aimed to investigate auditory brain processing of musical sounds relevant to prosody processing in adolescent CI-users who have received their implant in childhood. Furthermore, we aimed to investigate the potential impact of intensive musical training on adolescent CI-users’ discrimination...

  2. Similarity on neural stem cells and brain tumor stem cells in transgenic brain tumor mouse models

    Institute of Scientific and Technical Information of China (English)

    Guanqun Qiao; Qingquan Li; Gang Peng; Jun Ma; Hongwei Fan; Yingbin Li

    2013-01-01

    Although it is believed that glioma is derived from brain tumor stem cells, the source and molecular signal pathways of these cells are stil unclear. In this study, we used stable doxycycline-inducible transgenic mouse brain tumor models (c-myc+/SV40Tag+/Tet-on+) to explore the malignant trans-formation potential of neural stem cells by observing the differences of neural stem cel s and brain tumor stem cells in the tumor models. Results showed that chromosome instability occurred in brain tumor stem cells. The numbers of cytolysosomes and autophagosomes in brain tumor stem cells and induced neural stem cel s were lower and the proliferative activity was obviously stronger than that in normal neural stem cells. Normal neural stem cells could differentiate into glial fibril ary acidic protein-positive and microtubule associated protein-2-positive cells, which were also negative for nestin. However, glial fibril ary acidic protein/nestin, microtubule associated protein-2/nestin, and glial fibril ary acidic protein/microtubule associated protein-2 double-positive cells were found in induced neural stem cells and brain tumor stem cel s. Results indicate that induced neural stem cells are similar to brain tumor stem cells, and are possibly the source of brain tumor stem cells.

  3. Cross-Modal Functional Reorganization of Visual and Auditory Cortex in Adult Cochlear Implant Users Identified with fNIRS.

    Science.gov (United States)

    Chen, Ling-Chia; Sandmann, Pascale; Thorne, Jeremy D; Bleichner, Martin G; Debener, Stefan

    2016-01-01

    Cochlear implant (CI) users show higher auditory-evoked activations in visual cortex and higher visual-evoked activation in auditory cortex compared to normal hearing (NH) controls, reflecting functional reorganization of both visual and auditory modalities. Visual-evoked activation in auditory cortex is a maladaptive functional reorganization whereas auditory-evoked activation in visual cortex is beneficial for speech recognition in CI users. We investigated their joint influence on CI users' speech recognition, by testing 20 postlingually deafened CI users and 20 NH controls with functional near-infrared spectroscopy (fNIRS). Optodes were placed over occipital and temporal areas to measure visual and auditory responses when presenting visual checkerboard and auditory word stimuli. Higher cross-modal activations were confirmed in both auditory and visual cortex for CI users compared to NH controls, demonstrating that functional reorganization of both auditory and visual cortex can be identified with fNIRS. Additionally, the combined reorganization of auditory and visual cortex was found to be associated with speech recognition performance. Speech performance was good as long as the beneficial auditory-evoked activation in visual cortex was higher than the visual-evoked activation in the auditory cortex. These results indicate the importance of considering cross-modal activations in both visual and auditory cortex for potential clinical outcome estimation.

  4. Cross-Modal Functional Reorganization of Visual and Auditory Cortex in Adult Cochlear Implant Users Identified with fNIRS

    Directory of Open Access Journals (Sweden)

    Ling-Chia Chen

    2016-01-01

    Full Text Available Cochlear implant (CI users show higher auditory-evoked activations in visual cortex and higher visual-evoked activation in auditory cortex compared to normal hearing (NH controls, reflecting functional reorganization of both visual and auditory modalities. Visual-evoked activation in auditory cortex is a maladaptive functional reorganization whereas auditory-evoked activation in visual cortex is beneficial for speech recognition in CI users. We investigated their joint influence on CI users’ speech recognition, by testing 20 postlingually deafened CI users and 20 NH controls with functional near-infrared spectroscopy (fNIRS. Optodes were placed over occipital and temporal areas to measure visual and auditory responses when presenting visual checkerboard and auditory word stimuli. Higher cross-modal activations were confirmed in both auditory and visual cortex for CI users compared to NH controls, demonstrating that functional reorganization of both auditory and visual cortex can be identified with fNIRS. Additionally, the combined reorganization of auditory and visual cortex was found to be associated with speech recognition performance. Speech performance was good as long as the beneficial auditory-evoked activation in visual cortex was higher than the visual-evoked activation in the auditory cortex. These results indicate the importance of considering cross-modal activations in both visual and auditory cortex for potential clinical outcome estimation.

  5. [Long-latency auditory evoked potentials in cochlear implants].

    Science.gov (United States)

    Mata, J J; Jiménez, J M; Pérez, J; Postigo, A; Roldán, B

    1999-01-01

    Cortical evoked potentials were evaluated in patients with cochlear implants. In a group of 8 adults of different ages, the lingual state before implantation and during rehabilitation were evaluated. Using cortical evoked potentials, the results of the P300 wave in response to two tones, one frequent (1,000 Hz) and the other infrequent (2,000 Hz), presented at 70 and 80 dB HL were studied. Results were analyzed and compared in relation to locutive state, rehabilitation stage, and intensity of stimulus. Absolute latencies did not differ significantly. However, latency values in relation to reaction time were significantly longer in prelingual than in postlingual patients (p test). The results confirmed the normality of central cognitive processes in patients with cochlear implants in objective assessment of P300 latency. The results suggest differences between prelingual and postlingual patients in relation to central signal processing.

  6. Unanesthetized auditory cortex exhibits multiple codes for gaps in cochlear implant pulse trains.

    Science.gov (United States)

    Kirby, Alana E; Middlebrooks, John C

    2012-02-01

    Cochlear implant listeners receive auditory stimulation through amplitude-modulated electric pulse trains. Auditory nerve studies in animals demonstrate qualitatively different patterns of firing elicited by low versus high pulse rates, suggesting that stimulus pulse rate might influence the transmission of temporal information through the auditory pathway. We tested in awake guinea pigs the temporal acuity of auditory cortical neurons for gaps in cochlear implant pulse trains. Consistent with results using anesthetized conditions, temporal acuity improved with increasing pulse rates. Unlike the anesthetized condition, however, cortical neurons responded in the awake state to multiple distinct features of the gap-containing pulse trains, with the dominant features varying with stimulus pulse rate. Responses to the onset of the trailing pulse train (Trail-ON) provided the most sensitive gap detection at 1,017 and 4,069 pulse-per-second (pps) rates, particularly for short (25 ms) leading pulse trains. In contrast, under conditions of 254 pps rate and long (200 ms) leading pulse trains, a sizeable fraction of units demonstrated greater temporal acuity in the form of robust responses to the offsets of the leading pulse train (Lead-OFF). Finally, TONIC responses exhibited decrements in firing rate during gaps, but were rarely the most sensitive feature. Unlike results from anesthetized conditions, temporal acuity of the most sensitive units was nearly as sharp for brief as for long leading bursts. The differences in stimulus coding across pulse rates likely originate from pulse rate-dependent variations in adaptation in the auditory nerve. Two marked differences from responses to acoustic stimulation were: first, Trail-ON responses to 4,069 pps trains encoded substantially shorter gaps than have been observed with acoustic stimuli; and second, the Lead-OFF gap coding seen for <15 ms gaps in 254 pps stimuli is not seen in responses to sounds. The current results may help

  7. Comparisons of Auditory Performance and Speech Intelligibility after Cochlear Implant Reimplantation in Mandarin-Speaking Users

    Directory of Open Access Journals (Sweden)

    Chung-Feng Hwang

    2016-01-01

    Full Text Available Objectives. We evaluated the causes, hearing, and speech performance before and after cochlear implant reimplantation in Mandarin-speaking users. Methods. In total, 589 patients who underwent cochlear implantation in our medical center between 1999 and 2014 were reviewed retrospectively. Data related to demographics, etiologies, implant-related information, complications, and hearing and speech performance were collected. Results. In total, 22 (3.74% cases were found to have major complications. Infection (n=12 and hard failure of the device (n=8 were the most common major complications. Among them, 13 were reimplanted in our hospital. The mean scores of the Categorical Auditory Performance (CAP and the Speech Intelligibility Rating (SIR obtained before and after reimplantation were 5.5 versus 5.8 and 3.7 versus 4.3, respectively. The SIR score after reimplantation was significantly better than preoperation. Conclusions. Cochlear implantation is a safe procedure with low rates of postsurgical revisions and device failures. The Mandarin-speaking patients in this study who received reimplantation had restored auditory performance and speech intelligibility after surgery. Device soft failure was rare in our series, calling attention to Mandarin-speaking CI users requiring revision of their implants due to undesirable symptoms or decreasing performance of uncertain cause.

  8. Cerebral and brain stem Langerhans cell histiocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Breidahl, W.H. (Dept. of Radiology, Royal Perth Hospital, Nedlands (Australia)); Ives, F.J. (Dept. of Radiology, Royal Perth Hospital, Nedlands (Australia)); Khangure, M.S. (Dept. of Magnetic Resonance Imaging, Sir Charles Gairdner Hospital, Nedlands (Australia))

    1993-05-01

    Two patients with central nervous system manifestations of Langerhans cell histiocytosis, both with brain stem involvement, are reported. The onset of symptoms was at an age when the diagnosis might not have been considered. (orig.)

  9. Contribution of auditory working memory to speech understanding in mandarin-speaking cochlear implant users.

    Directory of Open Access Journals (Sweden)

    Duoduo Tao

    Full Text Available To investigate how auditory working memory relates to speech perception performance by Mandarin-speaking cochlear implant (CI users.Auditory working memory and speech perception was measured in Mandarin-speaking CI and normal-hearing (NH participants. Working memory capacity was measured using forward digit span and backward digit span; working memory efficiency was measured using articulation rate. Speech perception was assessed with: (a word-in-sentence recognition in quiet, (b word-in-sentence recognition in speech-shaped steady noise at +5 dB signal-to-noise ratio, (c Chinese disyllable recognition in quiet, (d Chinese lexical tone recognition in quiet. Self-reported school rank was also collected regarding performance in schoolwork.There was large inter-subject variability in auditory working memory and speech performance for CI participants. Working memory and speech performance were significantly poorer for CI than for NH participants. All three working memory measures were strongly correlated with each other for both CI and NH participants. Partial correlation analyses were performed on the CI data while controlling for demographic variables. Working memory efficiency was significantly correlated only with sentence recognition in quiet when working memory capacity was partialled out. Working memory capacity was correlated with disyllable recognition and school rank when efficiency was partialled out. There was no correlation between working memory and lexical tone recognition in the present CI participants.Mandarin-speaking CI users experience significant deficits in auditory working memory and speech performance compared with NH listeners. The present data suggest that auditory working memory may contribute to CI users' difficulties in speech understanding. The present pattern of results with Mandarin-speaking CI users is consistent with previous auditory working memory studies with English-speaking CI users, suggesting that the lexical

  10. Stem cells to regenerate the newborn brain

    NARCIS (Netherlands)

    van Velthoven, C.T.J.

    2011-01-01

    Perinatal hypoxia-ischemia (HI) is a frequent cause of perinatal morbidity and mortality with limited therapeutic options. In this thesis we investigate whether mesenchymal stem cells (MSC) regenerate the neonatal brain after HI injury. We show that transplantation of MSC after neonatal brain injury

  11. Quantitative map of multiple auditory cortical regions with a stereotaxic fine-scale atlas of the mouse brain

    OpenAIRE

    Hiroaki Tsukano; Masao Horie; Ryuichi Hishida; Kuniyuki Takahashi; Hirohide Takebayashi; Katsuei Shibuki

    2016-01-01

    Optical imaging studies have recently revealed the presence of multiple auditory cortical regions in the mouse brain. We have previously demonstrated, using flavoprotein fluorescence imaging, at least six regions in the mouse auditory cortex, including the anterior auditory field (AAF), primary auditory cortex (AI), the secondary auditory field (AII), dorsoanterior field (DA), dorsomedial field (DM), and dorsoposterior field (DP). While multiple regions in the visual cortex and somatosensory ...

  12. Cochlear Implant Outcomes and Genetic Mutations in Children with Ear and Brain Anomalies

    Directory of Open Access Journals (Sweden)

    Micol Busi

    2015-01-01

    Full Text Available Background. Specific clinical conditions could compromise cochlear implantation outcomes and drastically reduce the chance of an acceptable development of perceptual and linguistic capabilities. These conditions should certainly include the presence of inner ear malformations or brain abnormalities. The aims of this work were to study the diagnostic value of high resolution computed tomography (HRCT and magnetic resonance imaging (MRI in children with sensorineural hearing loss who were candidates for cochlear implants and to analyse the anatomic abnormalities of the ear and brain in patients who underwent cochlear implantation. We also analysed the effects of ear malformations and brain anomalies on the CI outcomes, speculating on their potential role in the management of language developmental disorders. Methods. The present study is a retrospective observational review of cochlear implant outcomes among hearing-impaired children who presented ear and/or brain anomalies at neuroimaging investigations with MRI and HRCT. Furthermore, genetic results from molecular genetic investigations (GJB2/GJB6 and, additionally, in selected cases, SLC26A4 or mitochondrial-DNA mutations on this study group were herein described. Longitudinal and cross-sectional analysis was conducted using statistical tests. Results. Between January 1, 1996 and April 1, 2012, at the ENT-Audiology Department of the University Hospital of Ferrara, 620 cochlear implantations were performed. There were 426 implanted children at the time of the present study (who were <18 years. Among these, 143 patients (64 females and 79 males presented ear and/or brain anomalies/lesions/malformations at neuroimaging investigations with MRI and HRCT. The age of the main study group (143 implanted children ranged from 9 months and 16 years (average = 4.4; median = 3.0. Conclusions. Good outcomes with cochlear implants are possible in patients who present with inner ear or brain abnormalities

  13. Role of bimodal stimulation for auditory-perceptual skills development in children with a unilateral cochlear implant.

    Science.gov (United States)

    Marsella, P; Giannantonio, S; Scorpecci, A; Pianesi, F; Micardi, M; Resca, A

    2015-12-01

    This is a prospective randomised study that evaluated the differences arising from a bimodal stimulation compared to a monaural electrical stimulation in deaf children, particularly in terms of auditory-perceptual skills development. We enrolled 39 children aged 12 to 36 months, suffering from severe-to-profound bilateral sensorineural hearing loss with residual hearing on at least one side. All were unilaterally implanted: 21 wore only the cochlear implant (CI) (unilateral CI group), while the other 18 used the CI and a contralateral hearing aid at the same time (bimodal group). They were assessed with a test battery designed to appraise preverbal and verbal auditory-perceptual skills immediately before and 6 and 12 months after implantation. No statistically significant differences were observed between groups at time 0, while at 6 and 12 months children in the bimodal group had better scores in each test than peers in the unilateral CI group. Therefore, although unilateral deafness/hearing does not undermine hearing acuity in normal listening, the simultaneous use of a CI and a contralateral hearing aid (binaural hearing through a bimodal stimulation) provides an advantage in terms of acquisition of auditory-perceptual skills, allowing children to achieve the basic milestones of auditory perception faster and in greater number than children with only one CI. Thus, "keeping awake" the contralateral auditory pathway, albeit not crucial in determining auditory acuity, guarantees benefits compared with the use of the implant alone. These findings provide initial evidence to establish shared guidelines for better rehabilitation of patients undergoing unilateral cochlear implantation, and add more evidence regarding the correct indications for bilateral cochlear implantation.

  14. Neurons Differentiated from Transplanted Stem Cells Respond Functionally to Acoustic Stimuli in the Awake Monkey Brain.

    Science.gov (United States)

    Wei, Jing-Kuan; Wang, Wen-Chao; Zhai, Rong-Wei; Zhang, Yu-Hua; Yang, Shang-Chuan; Rizak, Joshua; Li, Ling; Xu, Li-Qi; Liu, Li; Pan, Ming-Ke; Hu, Ying-Zhou; Ghanemi, Abdelaziz; Wu, Jing; Yang, Li-Chuan; Li, Hao; Lv, Long-Bao; Li, Jia-Li; Yao, Yong-Gang; Xu, Lin; Feng, Xiao-Li; Yin, Yong; Qin, Dong-Dong; Hu, Xin-Tian; Wang, Zheng-Bo

    2016-07-26

    Here, we examine whether neurons differentiated from transplanted stem cells can integrate into the host neural network and function in awake animals, a goal of transplanted stem cell therapy in the brain. We have developed a technique in which a small "hole" is created in the inferior colliculus (IC) of rhesus monkeys, then stem cells are transplanted in situ to allow for investigation of their integration into the auditory neural network. We found that some transplanted cells differentiated into mature neurons and formed synaptic input/output connections with the host neurons. In addition, c-Fos expression increased significantly in the cells after acoustic stimulation, and multichannel recordings indicated IC specific tuning activities in response to auditory stimulation. These results suggest that the transplanted cells have the potential to functionally integrate into the host neural network.

  15. The TLC: a novel auditory nucleus of the mammalian brain.

    Science.gov (United States)

    Saldaña, Enrique; Viñuela, Antonio; Marshall, Allen F; Fitzpatrick, Douglas C; Aparicio, M-Auxiliadora

    2007-11-28

    We have identified a novel nucleus of the mammalian brain and termed it the tectal longitudinal column (TLC). Basic histologic stains, tract-tracing techniques and three-dimensional reconstructions reveal that the rat TLC is a narrow, elongated structure spanning the midbrain tectum longitudinally. This paired nucleus is located close to the midline, immediately dorsal to the periaqueductal gray matter. It occupies what has traditionally been considered the most medial region of the deep superior colliculus and the most medial region of the inferior colliculus. The TLC differs from the neighboring nuclei of the superior and inferior colliculi and the periaqueductal gray by its distinct connections and cytoarchitecture. Extracellular electrophysiological recordings show that TLC neurons respond to auditory stimuli with physiologic properties that differ from those of neurons in the inferior or superior colliculi. We have identified the TLC in rodents, lagomorphs, carnivores, nonhuman primates, and humans, which indicates that the nucleus is conserved across mammals. The discovery of the TLC reveals an unexpected level of longitudinal organization in the mammalian tectum and raises questions as to the participation of this mesencephalic region in essential, yet completely unexplored, aspects of multisensory and/or sensorimotor integration.

  16. Neuroengineering tools/applications for bidirectional interfaces, brain-computer interfaces, and neuroprosthetic implants - a review of recent progress.

    Science.gov (United States)

    Rothschild, Ryan Mark

    2010-01-01

    The main focus of this review is to provide a holistic amalgamated overview of the most recent human in vivo techniques for implementing brain-computer interfaces (BCIs), bidirectional interfaces, and neuroprosthetics. Neuroengineering is providing new methods for tackling current difficulties; however neuroprosthetics have been studied for decades. Recent progresses are permitting the design of better systems with higher accuracies, repeatability, and system robustness. Bidirectional interfaces integrate recording and the relaying of information from and to the brain for the development of BCIs. The concepts of non-invasive and invasive recording of brain activity are introduced. This includes classical and innovative techniques like electroencephalography and near-infrared spectroscopy. Then the problem of gliosis and solutions for (semi-) permanent implant biocompatibility such as innovative implant coatings, materials, and shapes are discussed. Implant power and the transmission of their data through implanted pulse generators and wireless telemetry are taken into account. How sensation can be relayed back to the brain to increase integration of the neuroengineered systems with the body by methods such as micro-stimulation and transcranial magnetic stimulation are then addressed. The neuroprosthetic section discusses some of the various types and how they operate. Visual prosthetics are discussed and the three types, dependant on implant location, are examined. Auditory prosthetics, being cochlear or cortical, are then addressed. Replacement hand and limb prosthetics are then considered. These are followed by sections concentrating on the control of wheelchairs, computers and robotics directly from brain activity as recorded by non-invasive and invasive techniques.

  17. Intraoperative auditory steady state response measurements during Vibrant Soundbridge middle ear implantation in patients with mixed hearing loss: preliminary results.

    NARCIS (Netherlands)

    Verhaegen, V.J.O.; Mulder, J.J.S.; Noten, J.F.P.; Luijten, B.M.A.; Cremers, C.W.R.J.; Snik, A.F.M.

    2010-01-01

    OBJECTIVE: To optimize intraoperatively the coupling of the floating mass transducer (FMT) of the Vibrant Soundbridge middle ear implant to the round or oval cochlear window in patients with mixed hearing loss. STUDY DESIGN: Intraoperative measurement of objective hearing thresholds using auditory s

  18. The effect of music on auditory perception in cochlear-implant users and normal-hearing listeners

    NARCIS (Netherlands)

    Fuller, Christina Diechina

    2016-01-01

    Cochlear implants (CIs) are auditory prostheses for severely deaf people that do not benefit from conventional hearing aids. Speech perception is reasonably good with CIs; other signals such as music perception are challenging. First, the perception of music and music related perception in CI users

  19. Suppression and facilitation of auditory neurons through coordinated acoustic and midbrain stimulation: investigating a deep brain stimulator for tinnitus

    Science.gov (United States)

    Offutt, Sarah J.; Ryan, Kellie J.; Konop, Alexander E.; Lim, Hubert H.

    2014-12-01

    Objective. The inferior colliculus (IC) is the primary processing center of auditory information in the midbrain and is one site of tinnitus-related activity. One potential option for suppressing the tinnitus percept is through deep brain stimulation via the auditory midbrain implant (AMI), which is designed for hearing restoration and is already being implanted in deaf patients who also have tinnitus. However, to assess the feasibility of AMI stimulation for tinnitus treatment we first need to characterize the functional connectivity within the IC. Previous studies have suggested modulatory projections from the dorsal cortex of the IC (ICD) to the central nucleus of the IC (ICC), though the functional properties of these projections need to be determined. Approach. In this study, we investigated the effects of electrical stimulation of the ICD on acoustic-driven activity within the ICC in ketamine-anesthetized guinea pigs. Main Results. We observed ICD stimulation induces both suppressive and facilitatory changes across ICC that can occur immediately during stimulation and remain after stimulation. Additionally, ICD stimulation paired with broadband noise stimulation at a specific delay can induce greater suppressive than facilitatory effects, especially when stimulating in more rostral and medial ICD locations. Significance. These findings demonstrate that ICD stimulation can induce specific types of plastic changes in ICC activity, which may be relevant for treating tinnitus. By using the AMI with electrode sites positioned with the ICD and the ICC, the modulatory effects of ICD stimulation can be tested directly in tinnitus patients.

  20. Auditory event-related brain potentials for an early discrimination between normal and pathological brain aging

    Institute of Scientific and Technical Information of China (English)

    Juliana Dushanova; Mario Christov

    2013-01-01

    The brain as a system with gradually decreasing resources maximizes its chances by reorganizing neural networks to ensure efficient performance. Auditory event-related potentials were recorded in 28 healthy volunteers comprising 14 young and 14 elderly subjects in auditory discrimination motor task (low frequency tone – right hand movement and high frequency tone – left hand movement). The amplitudes of the sensory event-related potential components (N1, P2) were more pronounced with increasing age for either tone and this effect for P2 amplitude was more pronounced in the frontal region. The latency relationship of N1 between the groups was tone-dependent, while that of P2 was tone-independent with a prominent delay in the elderly group over all brain regions. The amplitudes of the cognitive components (N2, P3) diminished with increasing age and the hemispheric asymmetry of N2 (but not for P3) reduced with increasing age. Prolonged N2 latency with increasing age was widespread for either tone while between-group difference in P3 latency was tone-dependent. High frequency tone stimulation and movement requirements lead to P3 delay in the elderly group. The amplitude difference of the sensory components between the age groups could be due to a general greater alertness, less expressed habituation, or decline in the ability to retreat attentional resources from the stimuli in the elderly group. With aging, a neural circuit reorganization of the brain activity affects the cognitive processes. The approach used in this study is useful for an early discrimination between normal and pathological brain aging for early treatment of cognitive alterations and dementia.

  1. Effects of deafness and cochlear implant use on temporal response characteristics in cat primary auditory cortex.

    Science.gov (United States)

    Fallon, James B; Shepherd, Robert K; Nayagam, David A X; Wise, Andrew K; Heffer, Leon F; Landry, Thomas G; Irvine, Dexter R F

    2014-09-01

    We have previously shown that neonatal deafness of 7-13 months duration leads to loss of cochleotopy in the primary auditory cortex (AI) that can be reversed by cochlear implant use. Here we describe the effects of a similar duration of deafness and cochlear implant use on temporal processing. Specifically, we compared the temporal resolution of neurons in AI of young adult normal-hearing cats that were acutely deafened and implanted immediately prior to recording with that in three groups of neonatally deafened cats. One group of neonatally deafened cats received no chronic stimulation. The other two groups received up to 8 months of either low- or high-rate (50 or 500 pulses per second per electrode, respectively) stimulation from a clinical cochlear implant, initiated at 10 weeks of age. Deafness of 7-13 months duration had no effect on the duration of post-onset response suppression, latency, latency jitter, or the stimulus repetition rate at which units responded maximally (best repetition rate), but resulted in a statistically significant reduction in the ability of units to respond to every stimulus in a train (maximum following rate). None of the temporal response characteristics of the low-rate group differed from those in acutely deafened controls. In contrast, high-rate stimulation had diverse effects: it resulted in decreased suppression duration, longer latency and greater jitter relative to all other groups, and an increase in best repetition rate and cut-off rate relative to acutely deafened controls. The minimal effects of moderate-duration deafness on temporal processing in the present study are in contrast to its previously-reported pronounced effects on cochleotopy. Much longer periods of deafness have been reported to result in significant changes in temporal processing, in accord with the fact that duration of deafness is a major factor influencing outcome in human cochlear implantees.

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

    Science.gov (United States)

    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.

  3. Brain stem evoked response audiometry A Review

    OpenAIRE

    Balasubramanian Thiagarajan

    2015-01-01

    Brain stem evoked response audiometry (BERA) is a useful objective assessement of hearing. Major advantage of this procedure is its ability to test even infants in whom conventional audiometry may not be useful. This investigation can be used as a screening test for deafness in high risk infants. Early diagnosis and rehabilitation will reduce disability in these children. This article attempts to review the published literature on this subject. Methadology: Internet search using goog...

  4. Auditory Neural Prostheses – A Window to the Future

    Directory of Open Access Journals (Sweden)

    Mohan Kameshwaran

    2015-06-01

    or absent on both sides and hence, a cochlear implant (CI would be inef­fective. In such patients, the brainstem implant bypasses the damaged / absent cochlear nerves and directly stimulates the cochlear nucleus in the brainstem.  The auditory midbrain implant (AMI has been designed for stimulation of the auditory midbrain, particularly the central nucleus of inferior colliculus (ICC. It is used especially in patients with large neurofibromatosis type 2 (NF2 wherein tumor induced damage to the brain­stem/cochlear nucleus often co-exists. The efficacy and safety of auditory neural prostheses is well proven. Advancements in technology will enhance the benefit provided by these prostheses.  Hearing loss is one of the commonest congenital anomalies to affect children world-over. The incidence of congenital hearing loss is more pronounced in developing countries like the Indian sub-continent, especially with the problems of consanguinity. Hearing loss is a double tragedy, as it leads to not only deafness but also language deprivation. However, hearing loss is the only truly remediable handicap, due to remarkable advances in biomedical engineering and surgical techniques. Auditory neural prostheses help to augment or restore hearing by integration of an external circuitry with the peripheral hearing apparatus and the central circuitry of the brain. A cochlear implant (CI is a surgically implantable device that helps restore hearing in patients with severe-profound hearing loss, unresponsive to amplification by conventional hearing aids. CIs are electronic devices designed to detect mechanical sound energy and convert it into electrical signals that can be delivered to the coch­lear nerve, bypassing the damaged hair cells of the coch­lea. The only true prerequisite is an intact auditory nerve. The emphasis is on implantation as early as possible to maximize speech understanding and perception. Bilateral CI has significant benefits which include improved speech

  5. Prediction of auditory and visual p300 brain-computer interface aptitude.

    Directory of Open Access Journals (Sweden)

    Sebastian Halder

    Full Text Available OBJECTIVE: Brain-computer interfaces (BCIs provide a non-muscular communication channel for patients with late-stage motoneuron disease (e.g., amyotrophic lateral sclerosis (ALS or otherwise motor impaired people and are also used for motor rehabilitation in chronic stroke. Differences in the ability to use a BCI vary from person to person and from session to session. A reliable predictor of aptitude would allow for the selection of suitable BCI paradigms. For this reason, we investigated whether P300 BCI aptitude could be predicted from a short experiment with a standard auditory oddball. METHODS: Forty healthy participants performed an electroencephalography (EEG based visual and auditory P300-BCI spelling task in a single session. In addition, prior to each session an auditory oddball was presented. Features extracted from the auditory oddball were analyzed with respect to predictive power for BCI aptitude. RESULTS: Correlation between auditory oddball response and P300 BCI accuracy revealed a strong relationship between accuracy and N2 amplitude and the amplitude of a late ERP component between 400 and 600 ms. Interestingly, the P3 amplitude of the auditory oddball response was not correlated with accuracy. CONCLUSIONS: Event-related potentials recorded during a standard auditory oddball session moderately predict aptitude in an audiory and highly in a visual P300 BCI. The predictor will allow for faster paradigm selection. SIGNIFICANCE: Our method will reduce strain on patients because unsuccessful training may be avoided, provided the results can be generalized to the patient population.

  6. Emotional words induce enhanced brain activity in schizophrenic patients with auditory hallucinations.

    Science.gov (United States)

    Sanjuan, Julio; Lull, Juan J; Aguilar, Eduardo J; Martí-Bonmatí, Luis; Moratal, David; Gonzalez, José C; Robles, Montserrat; Keshavan, Matcheri S

    2007-01-15

    Neuroimaging studies of emotional response in schizophrenia have mainly used visual (faces) paradigms and shown globally reduced brain activity. None of these studies have used an auditory paradigm. Our principal aim is to evaluate the emotional response of patients with schizophrenia to neutral and emotional words. An auditory emotional paradigm based on the most frequent words heard by psychotic patients with auditory hallucinations was designed. This paradigm was applied to evaluate cerebral activation with functional magnetic resonance imaging (fMRI) in 11 patients with schizophrenia with persistent hallucinations and 10 healthy subjects. We found a clear enhanced activity of the frontal lobe, temporal cortex, insula, cingulate, and amygdala (mainly right side) in patients when hearing emotional words in comparison with controls. Our findings are consistent with other studies suggesting a relevant role for emotional response in the pathogenesis and treatment of auditory hallucinations.

  7. A Case Study Assessing the Auditory and Speech Development of Four Children Implanted with Cochlear Implants by the Chronological Age of 12 Months

    Directory of Open Access Journals (Sweden)

    Birgit May-Mederake

    2013-01-01

    Full Text Available Children with severe hearing loss most likely receive the greatest benefit from a cochlear implant (CI when implanted at less than 2 years of age. Children with a hearing loss may also benefit greater from binaural sensory stimulation. Four children who received their first CI under 12 months of age were included in this study. Effects on auditory development were determined using the German LittlEARS Auditory Questionnaire, closed- and open-set monosyllabic word tests, aided free-field, the Mainzer and Göttinger speech discrimination tests, Monosyllabic-Trochee-Polysyllabic (MTP, and Listening Progress Profile (LiP. Speech production and grammar development were evaluated using a German language speech development test (SETK, reception of grammar test (TROG-D and active vocabulary test (AWST-R. The data showed that children implanted under 12 months of age reached open-set monosyllabic word discrimination at an age of 24 months. LiP results improved over time, and children recognized 100% of words in the MTP test after 12 months. All children performed as well as or better than their hearing peers in speech production and grammar development. SETK showed that the speech development of these children was in general age appropriate. The data suggests that early hearing loss intervention benefits speech and language development and supports the trend towards early cochlear implantation. Furthermore, the data emphasizes the potential benefits associated with bilateral implantation.

  8. Temporal Resolution of ChR2 and Chronos in an Optogenetic-based Auditory Brainstem Implant Model: Implications for the Development and Application of Auditory Opsins

    Science.gov (United States)

    Hight, A. E.; Kozin, Elliott D.; Darrow, Keith; Lehmann, Ashton; Boyden, Edward; Brown, M. Christian; Lee, Daniel J.

    2015-01-01

    The contemporary auditory brainstem implant (ABI) performance is limited by reliance on electrical stimulation with its accompanying channel cross talk and current spread to non-auditory neurons. A new generation ABI based on optogenetic-technology may ameliorate limitations fundamental to electrical neurostimulation. The most widely studied opsin is channelrhodopsin-2 (ChR2); however, its relatively slow kinetic properties may prevent the encoding of auditory information at high stimulation rates. In the present study, we compare the temporal resolution of light-evoked responses of a recently developed fast opsin, Chronos, to ChR2 in a murine ABI model. Viral mediated gene transfer via a posterolateral craniotomy was used to express Chronos or ChR2 in the mouse nucleus (CN). Following a four to six week incubation period, blue light (473 nm) was delivered via an optical fiber placed directly on the surface of the infected CN, and neural activity was recorded in the contralateral inferior colliculus (IC). Both ChR2 and Chronos evoked sustained responses to all stimuli, even at high driven rates. In addition, optical stimulation evoked excitatory responses throughout the tonotopic axis of the IC. Synchrony of the light-evoked response to stimulus rates of 14–448 pulses/s was higher in Chronos compared to ChR2 mice (p<0.05 at 56, 168, and 224 pulses/s). Our results demonstrate that Chronos has the ability to drive the auditory system at higher stimulation rates than ChR2 and may be a more ideal opsin for manipulation of auditory pathways in future optogenetic-based neuroprostheses. PMID:25598479

  9. Brain Cancer Stem Cells: Current Status on Glioblastoma Multiforme

    OpenAIRE

    2011-01-01

    Glioblastoma multiforme (GBM), an aggressive brain tumor of astrocytic/neural stem cell origin, represents one of the most incurable cancers. GBM tumors are highly heterogeneous. However, most tumors contain a subpopulation of cells that display neural stem cell characteristics in vitro and that can generate a new brain tumor upon transplantation in mice. Hence, previously identified molecular pathways regulating neural stem cell biology were found to represent the cornerstone of GBM stem cel...

  10. The effects of iron supplementation on auditory brain-stem response with iron deficiency anemia in rats%缺铁性贫血治疗前后听性脑干反应的变化

    Institute of Scientific and Technical Information of China (English)

    周本忠; 王胜国; 王琼; 孙爱华; 马玉龙; 沈建军

    2001-01-01

    Objective:To evaluate the therapeutic methods of sensorineural hearing loss with iron deficiency anemia and their effects. Method:Sixty-eight Wistar rats were randomly divided into 3 groups: Group A (iron deficiency group A) 24 rats, group B (iron deficiency group B) 24 rats and group C (control group) 20 rats. Group A and B were fed with iron deficiency diet for 6 weeks. By analyzing ABR and DPOAE, hearing loss was detected in group A and B. Then,group A was given iron supplementation diet and hyperbaric oxygen therapies. and group B was given iron supplementation diet only. Result:The auditory thresholds and period latencies (PL) of I waves of ABR and DPOAE amplitude in 2 kHz and 3kHz within group A and B were significantly different before and after treatment (P<0.05). But the effects of treatment between these two groups had not significant differences (P>0.05). Conclusion: It suggested that good results can be obtained by early iron supplementation in iron deficiency hearing loss cases. Hyperbaric Oxygen therapy may not be necessary.%目的:探讨缺铁性贫血导致感音神经性聋的治疗方法及疗效。方法:将68只Wistar大鼠分成3组:48只通过缺铁饮食制作缺铁性贫血模型,缺铁A组和B组各24只;另设标准对照C组正常大鼠20只。将A、B两组进行缺铁饲养6周,检测听性脑干反应(ABR),每组各随机取样10只检测畸变产物耳声发射(DPOAE),再分别给予铁剂加高压氧治疗和单纯铁剂治疗。结果:缺铁Wistar大鼠经6周饲养,较实验前ABR听觉阈值提高和Ⅰ波PL延长,经过两种不同方案治疗6周,均取得明显效果(P<0.05),但两组差异无显著性。结论:对于缺铁性贫血造成感音神经性耳聋,早期给予及时的铁剂治疗疗效好,而高压氧用于治疗此类耳聋并非必要。

  11. Jumpstarting auditory learning in children with cochlear implants through music experiences.

    Science.gov (United States)

    Barton, Christine; Robbins, Amy McConkey

    2015-09-01

    Musical experiences are a valuable part of the lives of children with cochlear implants (CIs). In addition to the pleasure, relationships and emotional outlet provided by music, it serves to enhance or 'jumpstart' other auditory and cognitive skills that are critical for development and learning throughout the lifespan. Musicians have been shown to be 'better listeners' than non-musicians with regard to how they perceive and process sound. A heuristic model of music therapy is reviewed, including six modulating factors that may account for the auditory advantages demonstrated by those who participate in music therapy. The integral approach to music therapy is described along with the hybrid approach to pediatric language intervention. These approaches share the characteristics of placing high value on ecologically valid therapy experiences, i.e., engaging in 'real' music and 'real' communication. Music and language intervention techniques used by the authors are presented. It has been documented that children with CIs consistently have lower music perception scores than do their peers with normal hearing (NH). On the one hand, this finding matters a great deal because it provides parameters for setting reasonable expectations and highlights the work still required to improve signal processing with the devices so that they more accurately transmit music to CI listeners. On the other hand, the finding might not matter much if we assume that music, even in its less-than-optimal state, functions for CI children, as for NH children, as a developmental jumpstarter, a language-learning tool, a cognitive enricher, a motivator, and an attention enhancer.

  12. Photodynamic therapy for implanted VX2 tumor in rabbit brains

    Science.gov (United States)

    Li, Fei; Feng, Hua; Lin, Jiangkai; Zhu, Gang; Chen, Zhi; Li, Cong-yan

    2005-07-01

    To evaluate the therapeutic effect and the safety of single photodynamic therapy (PDT) with hematoporphyrin derivative produced in China, 60 New Zealand adult rabbits with VX2 tumor implanted into the brain were divided randomly into non-PDT-group and PDT-group. 36 rabbits of the PDT-group were performed photodynamic therapy. The survival time, neurological deteriorations, intracranial pressure (ICP), histology, pathology, tumor volume and brain water content were measured. Other 12 rabbits were received hematoporphyrin derivative and light irradiation of the normal brain. The ICP, histology, pathology, and brain water content were measured. The result indicated that Simple PDT may elongate the average survival time of the rabbits with VX2 tumors significantly; kill tumor cells; cause transient brain edema and increase ICP, but it is safe to be used in treating brain tumor.

  13. Auditory, Visual, and Auditory-Visual Perception of Emotions by Individuals with Cochlear Implants, Hearing Aids, and Normal Hearing

    Science.gov (United States)

    Most, Tova; Aviner, Chen

    2009-01-01

    This study evaluated the benefits of cochlear implant (CI) with regard to emotion perception of participants differing in their age of implantation, in comparison to hearing aid users and adolescents with normal hearing (NH). Emotion perception was examined by having the participants identify happiness, anger, surprise, sadness, fear, and disgust.…

  14. Auditory, Visual, and Auditory-Visual Speech Perception by Individuals with Cochlear Implants versus Individuals with Hearing Aids

    Science.gov (United States)

    Most, Tova; Rothem, Hilla; Luntz, Michal

    2009-01-01

    The researchers evaluated the contribution of cochlear implants (CIs) to speech perception by a sample of prelingually deaf individuals implanted after age 8 years. This group was compared with a group with profound hearing impairment (HA-P), and with a group with severe hearing impairment (HA-S), both of which used hearing aids. Words and…

  15. A Wireless 32-Channel Implantable Bidirectional Brain Machine Interface.

    Science.gov (United States)

    Su, Yi; Routhu, Sudhamayee; Moon, Kee S; Lee, Sung Q; Youm, WooSub; Ozturk, Yusuf

    2016-01-01

    All neural information systems (NIS) rely on sensing neural activity to supply commands and control signals for computers, machines and a variety of prosthetic devices. Invasive systems achieve a high signal-to-noise ratio (SNR) by eliminating the volume conduction problems caused by tissue and bone. An implantable brain machine interface (BMI) using intracortical electrodes provides excellent detection of a broad range of frequency oscillatory activities through the placement of a sensor in direct contact with cortex. This paper introduces a compact-sized implantable wireless 32-channel bidirectional brain machine interface (BBMI) to be used with freely-moving primates. The system is designed to monitor brain sensorimotor rhythms and present current stimuli with a configurable duration, frequency and amplitude in real time to the brain based on the brain activity report. The battery is charged via a novel ultrasonic wireless power delivery module developed for efficient delivery of power into a deeply-implanted system. The system was successfully tested through bench tests and in vivo tests on a behaving primate to record the local field potential (LFP) oscillation and stimulate the target area at the same time.

  16. Implanted neural progenitor cells regulate glial reaction to brain injury and establish gap junctions with host glial cells.

    Science.gov (United States)

    Talaverón, Rocío; Matarredona, Esperanza R; de la Cruz, Rosa R; Macías, David; Gálvez, Victoria; Pastor, Angel M

    2014-04-01

    Transplantation of neural stem/progenitor cells (NPCs) in the lesioned brain is able to restore morphological and physiological alterations induced by different injuries. The local microenvironment created at the site of grafting and the communication between grafted and host cells are crucial in the beneficial effects attributed to the NPC implants. We have previously described that NPC transplantation in an animal model of central axotomy restores firing properties and synaptic coverage of lesioned neurons and modulates their trophic factor content. In this study, we aim to explore anatomical relationships between implanted NPCs and host glia that might account for the implant-induced neuroprotective effects. Postnatal rat subventricular zone NPCs were isolated and grafted in adult rats after transection of the medial longitudinal fascicle. Brains were removed and analyzed eight weeks later. Immunohistochemistry for different glial markers revealed that NPC-grafted animals displayed significantly greater microglial activation than animals that received only vehicle injections. Implanted NPCs were located in close apposition to activated microglia and reactive astrocytes. The gap junction protein connexin43 was present in NPCs and glial cells at the lesion site and was often found interposed within adjacent implanted and glial cells. Gap junctions were identified between implanted NPCs and host astrocytes and less frequently between NPCs and microglia. Our results show that implanted NPCs modulate the glial reaction to lesion and establish the possibility of communication through gap junctions between grafted and host glial cells which might be involved in the restorative effects of NPC implants.

  17. Clinical applied value of brain stem auditory evoked potential in facial neuritis patients combined the damage of other cranial nerves%伴其他颅神经症状的面神经炎患者治疗前后的脑干听觉诱发电位研究

    Institute of Scientific and Technical Information of China (English)

    王金风; 王民

    2012-01-01

    Objective: To explore the clinical applied value of brain stem auditoryk evoed potential (BAEP)in facial neuritis patients combined with damage of other cranial nerves. Methods: Fifty facial neuritis patients combined with damage of other cranial nerves were selected to get BAEP information) the results before and after treatment were analyzed. Results;The inter-peak latencies (IPL) of Ⅰ -- Ⅲ, Ⅲ - V . Ⅰ - V were significantly shorten(P<0. 01)after treatment of the. More than one IPL shortened IPL took up 84%. 74% cases had prolonged potential latencies (PL) of Wave I , Ⅲ and V with more than one shortened or disappeared waveform. In 69 % cases with amplitude of wave V increased and ratio of V/ I more than 0. 5 or ILD of bilateral Wave V was less than 0. 3 ms, IPL of Ⅲ - V shorter than that of Ⅰ - Ⅲ. Conclusion:Facial neuritis involves not only medial surface nerves of foramen stylomastoi-deum but also brainstem and/or other cranial nerves . BAEP can objectively reflect the function of audi-tory system and brain stem, and can be used to follow-up with patients with facial neuritis.%目的:观察伴其他颅神经症状的面神经炎患者治疗前后的脑干听觉诱发电位(BAEP)表现.方法:选择50例面神经炎伴其他颅神经症状的患者进行BAEP检测,并进行治疗前后对比.结果:与治疗前相比,治疗后Ⅱ-Ⅲ、Ⅲ-Ⅴ、Ⅰ-Ⅴ波IPL明显缩短(P<0.01),其中有一个以上的IPL缩短者42例占84%;Ⅰ、Ⅲ、Ⅴ波PL有一个以上缩短或治疗前BAEP波形消失而于治疗后出现者37例占74%;Ⅴ波波幅增高并且Ⅴ/Ⅰ IPL比大于0.5或双侧Ⅴ波侧间潜伏期差(IDL)小于0.3 ms,Ⅲ-Ⅴ波IPL小于Ⅰ-Ⅲ波IPL的35例占70%.结论:面神经炎不仅累及茎乳孔内面神经,还可累及脑干和其他颅神经.BAEP可以客观地反映面神经炎患者听觉系统和脑干功能,因此可以用于对该类患者进行疗效观察.

  18. Reestablishing speech understanding through musical ear training after cochlear implantation: a study of the potential cortical plasticity in the brain

    DEFF Research Database (Denmark)

    Petersen, Bjørn; Mortensen, Malene V; Gjedde, Albert

    2009-01-01

    Cochlear implants (CIs) provide impressive speech perception for persons with severe hearing loss, but many CI recipients fail in perceiving speech prosody and music. Successful rehabilitation depends on cortical plasticity in the brain and postoperative measures. The present study evaluates...... the behavioral and neurologic effects of musical ear training on CI users' speech and music perception. The goal is to find and work out musical methods to improve CI users' auditory capabilities and, in a longer perspective, provide an efficient strategy for improving speech understanding for both adults...

  19. Effects of scanner acoustic noise on intrinsic brain activity during auditory stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Yakunina, Natalia [Kangwon National University, Institute of Medical Science, School of Medicine, Chuncheon (Korea, Republic of); Kangwon National University Hospital, Neuroscience Research Institute, Chuncheon (Korea, Republic of); Kang, Eun Kyoung [Kangwon National University Hospital, Department of Rehabilitation Medicine, Chuncheon (Korea, Republic of); Kim, Tae Su [Kangwon National University Hospital, Department of Otolaryngology, Chuncheon (Korea, Republic of); Kangwon National University, School of Medicine, Department of Otolaryngology, Chuncheon (Korea, Republic of); Min, Ji-Hoon [University of Michigan, Department of Biopsychology, Cognition, and Neuroscience, Ann Arbor, MI (United States); Kim, Sam Soo [Kangwon National University Hospital, Neuroscience Research Institute, Chuncheon (Korea, Republic of); Kangwon National University, School of Medicine, Department of Radiology, Chuncheon (Korea, Republic of); Nam, Eui-Cheol [Kangwon National University Hospital, Neuroscience Research Institute, Chuncheon (Korea, Republic of); Kangwon National University, School of Medicine, Department of Otolaryngology, Chuncheon (Korea, Republic of)

    2015-10-15

    Although the effects of scanner background noise (SBN) during functional magnetic resonance imaging (fMRI) have been extensively investigated for the brain regions involved in auditory processing, its impact on other types of intrinsic brain activity has largely been neglected. The present study evaluated the influence of SBN on a number of intrinsic connectivity networks (ICNs) during auditory stimulation by comparing the results obtained using sparse temporal acquisition (STA) with those using continuous acquisition (CA). Fourteen healthy subjects were presented with classical music pieces in a block paradigm during two sessions of STA and CA. A volume-matched CA dataset (CAm) was generated by subsampling the CA dataset to temporally match it with the STA data. Independent component analysis was performed on the concatenated STA-CAm datasets, and voxel data, time courses, power spectra, and functional connectivity were compared. The ICA revealed 19 ICNs; the auditory, default mode, salience, and frontoparietal networks showed greater activity in the STA. The spectral peaks in 17 networks corresponded to the stimulation cycles in the STA, while only five networks displayed this correspondence in the CA. The dorsal default mode and salience networks exhibited stronger correlations with the stimulus waveform in the STA. SBN appeared to influence not only the areas of auditory response but also the majority of other ICNs, including attention and sensory networks. Therefore, SBN should be regarded as a serious nuisance factor during fMRI studies investigating intrinsic brain activity under external stimulation or task loads. (orig.)

  20. HTLV-I associated myelopathy with multiple spotty areas in cerebral white matter and brain stem by MRI

    Energy Technology Data Exchange (ETDEWEB)

    Hara, Yasuo; Takahashi, Mitsuo; Yoshikawa, Hiroo; Yorifuji, Shirou; Tarui, Seiichiro

    1988-01-01

    A 48-year-old woman was admitted with complaints of urinary incontinence and gait disturbance, both of which had progressed slowly without any sign of remission. Family history was not contributory. Neurologically, extreme spasticity was recoginized in the lower limbs. Babinski sign was positive bilaterally. Flower-like atypical lymphocytes were seen in blood. Positive anti-HTLV-I antibody was confirmed in serum and spinal fluid by western blot. She was diagnosed as having HTLV-I associated myelopathy (HAM). CT reveald calcification in bilateral globus pallidus, and MRI revealed multiple spotty areas in cerebral white matter and brain stem, but no spinal cord lesion was detectable. Electrophysiologically, brain stem auditory evoked potential (BAEP) suggested the presence of bilateral brain stem lesions. Neither median nor posterior tibial nerve somatosensory evoked potentials were evoked, a finding suggesting the existence of spinal cord lesion. In this case, the lesion was not confined to spinal cord, it was also observed in brain stem and cerebral white matter. Such distinct lesions in cerebral white matter and brain stem have not been reported in patients with HAM. It is suggested that HTLV-I is probably associated with cerebral white matter and brain stem.

  1. Using auditory steady state responses to outline the functional connectivity in the tinnitus brain.

    Directory of Open Access Journals (Sweden)

    Winfried Schlee

    Full Text Available BACKGROUND: Tinnitus is an auditory phantom perception that is most likely generated in the central nervous system. Most of the tinnitus research has concentrated on the auditory system. However, it was suggested recently that also non-auditory structures are involved in a global network that encodes subjective tinnitus. We tested this assumption using auditory steady state responses to entrain the tinnitus network and investigated long-range functional connectivity across various non-auditory brain regions. METHODS AND FINDINGS: Using whole-head magnetoencephalography we investigated cortical connectivity by means of phase synchronization in tinnitus subjects and healthy controls. We found evidence for a deviating pattern of long-range functional connectivity in tinnitus that was strongly correlated with individual ratings of the tinnitus percept. Phase couplings between the anterior cingulum and the right frontal lobe and phase couplings between the anterior cingulum and the right parietal lobe showed significant condition x group interactions and were correlated with the individual tinnitus distress ratings only in the tinnitus condition and not in the control conditions. CONCLUSIONS: To the best of our knowledge this is the first study that demonstrates existence of a global tinnitus network of long-range cortical connections outside the central auditory system. This result extends the current knowledge of how tinnitus is generated in the brain. We propose that this global extend of the tinnitus network is crucial for the continuos perception of the tinnitus tone and a therapeutical intervention that is able to change this network should result in relief of tinnitus.

  2. Neuroengineering tools/applications for bidirectional interfaces, brain computer interfaces, and neuroprosthetic implants - a review of recent progress

    Directory of Open Access Journals (Sweden)

    Ryan M Rothschild

    2010-10-01

    Full Text Available The main focus of this review is to provide a holistic amalgamated overview of the most recent human in vivo techniques for implementing brain-computer interfaces (BCIs, bidirectional interfaces and neuroprosthetics. Neuroengineering is providing new methods for tackling current difficulties; however neuroprosthetics have been studied for decades. Recent progresses are permitting the design of better systems with higher accuracies, repeatability and system robustness. Bidirectional interfaces integrate recording and the relaying of information from and to the brain for the development of BCIs. The concepts of non-invasive and invasive recording of brain activity are introduced. This includes classical and innovative techniques like electroencephalography (EEG and near-infrared spectroscopy (NIRS. Then the problem of gliosis and solutions for (semi- permanent implant biocompatibility such as innovative implant coatings, materials and shapes are discussed. Implant power and the transmission of their data through implanted pulse generators (IPGs and wireless telemetry are taken into account. How sensation can be relayed back to the brain to increase integration of the neuroengineered systems with the body by methods such as micro-stimulation and transcranial magnetic stimulation (TMS are then addressed. The neuroprosthetic section discusses some of the various types and how they operate. Visual prosthetics are discussed and the three types, dependant on implant location, are examined. Auditory prosthetics, being cochlear or cortical, are then addressed. Replacement hand and limb prosthetics are then considered. These are followed by sections concentrating on the control of wheelchairs, computers and robotics directly from brain activity as recorded by non-invasive and invasive techniques.

  3. Neurogenesis in the brain auditory pathway of a marsupial, the northern native cat (Dasyurus hallucatus)

    Energy Technology Data Exchange (ETDEWEB)

    Aitkin, L.; Nelson, J.; Farrington, M.; Swann, S. (Department of Physiology, Monash University, Melbourne (Australia))

    1991-07-08

    Neurogenesis in the auditory pathway of the marsupial Dasyurus hallucatus was studied. Intraperitoneal injections of tritiated thymidine (20-40 microCi) were made into pouch-young varying from 1 to 56 days pouch-life. Animals were killed as adults and brain sections were prepared for autoradiography and counterstained with a Nissl stain. Neurons in the ventral cochlear nucleus were generated prior to 3 days pouch-life, in the superior olive at 5-7 days, and in the dorsal cochlear nucleus over a prolonged period. Inferior collicular neurogenesis lagged behind that in the medial geniculate, the latter taking place between days 3 and 9 and the former between days 7 and 22. Neurogenesis began in the auditory cortex on day 9 and was completed by about day 42. Thus neurogenesis was complete in the medullary auditory nuclei before that in the midbrain commenced, and in the medial geniculate before that in the auditory cortex commenced. The time course of neurogenesis in the auditory pathway of the native cat was very similar to that in another marsupial, the brushtail possum. For both, neurogenesis occurred earlier than in eutherian mammals of a similar size but was more protracted.

  4. Auditory perception and syntactic cognition: brain activity-based decoding within and across subjects.

    Science.gov (United States)

    Herrmann, Björn; Maess, Burkhard; Kalberlah, Christian; Haynes, John-Dylan; Friederici, Angela D

    2012-05-01

    The present magnetoencephalography study investigated whether the brain states of early syntactic and auditory-perceptual processes can be decoded from single-trial recordings with a multivariate pattern classification approach. In particular, it was investigated whether the early neural activation patterns in response to rule violations in basic auditory perception and in high cognitive processes (syntax) reflect a functional organization that largely generalizes across individuals or is subject-specific. On this account, subjects were auditorily presented with correct sentences, syntactically incorrect sentences, correct sentences including an interaural time difference change, and sentences containing both violations. For the analysis, brain state decoding was carried out within and across subjects with three pairwise classifications. Neural patterns elicited by each of the violation sentences were separately classified with the patterns elicited by the correct sentences. The results revealed the highest decoding accuracies over temporal cortex areas for all three classification types. Importantly, both the magnitude and the spatial distribution of decoding accuracies for the early neural patterns were very similar for within-subject and across-subject decoding. At the same time, across-subject decoding suggested a hemispheric bias, with the most consistent patterns in the left hemisphere. Thus, the present data show that not only auditory-perceptual processing brain states but also cognitive brain states of syntactic rule processing can be decoded from single-trial brain activations. Moreover, the findings indicate that the neural patterns in response to syntactic cognition and auditory perception reflect a functional organization that is highly consistent across individuals.

  5. Localized brain activation related to the strength of auditory learning in a parrot.

    Science.gov (United States)

    Eda-Fujiwara, Hiroko; Imagawa, Takuya; Matsushita, Masanori; Matsuda, Yasushi; Takeuchi, Hiro-Aki; Satoh, Ryohei; Watanabe, Aiko; Zandbergen, Matthijs A; Manabe, Kazuchika; Kawashima, Takashi; Bolhuis, Johan J

    2012-01-01

    Parrots and songbirds learn their vocalizations from a conspecific tutor, much like human infants acquire spoken language. Parrots can learn human words and it has been suggested that they can use them to communicate with humans. The caudomedial pallium in the parrot brain is homologous with that of songbirds, and analogous to the human auditory association cortex, involved in speech processing. Here we investigated neuronal activation, measured as expression of the protein product of the immediate early gene ZENK, in relation to auditory learning in the budgerigar (Melopsittacus undulatus), a parrot. Budgerigar males successfully learned to discriminate two Japanese words spoken by another male conspecific. Re-exposure to the two discriminanda led to increased neuronal activation in the caudomedial pallium, but not in the hippocampus, compared to untrained birds that were exposed to the same words, or were not exposed to words. Neuronal activation in the caudomedial pallium of the experimental birds was correlated significantly and positively with the percentage of correct responses in the discrimination task. These results suggest that in a parrot, the caudomedial pallium is involved in auditory learning. Thus, in parrots, songbirds and humans, analogous brain regions may contain the neural substrate for auditory learning and memory.

  6. Localized brain activation related to the strength of auditory learning in a parrot.

    Directory of Open Access Journals (Sweden)

    Hiroko Eda-Fujiwara

    Full Text Available Parrots and songbirds learn their vocalizations from a conspecific tutor, much like human infants acquire spoken language. Parrots can learn human words and it has been suggested that they can use them to communicate with humans. The caudomedial pallium in the parrot brain is homologous with that of songbirds, and analogous to the human auditory association cortex, involved in speech processing. Here we investigated neuronal activation, measured as expression of the protein product of the immediate early gene ZENK, in relation to auditory learning in the budgerigar (Melopsittacus undulatus, a parrot. Budgerigar males successfully learned to discriminate two Japanese words spoken by another male conspecific. Re-exposure to the two discriminanda led to increased neuronal activation in the caudomedial pallium, but not in the hippocampus, compared to untrained birds that were exposed to the same words, or were not exposed to words. Neuronal activation in the caudomedial pallium of the experimental birds was correlated significantly and positively with the percentage of correct responses in the discrimination task. These results suggest that in a parrot, the caudomedial pallium is involved in auditory learning. Thus, in parrots, songbirds and humans, analogous brain regions may contain the neural substrate for auditory learning and memory.

  7. Stem Cells and the Origin and Propagation of Brain Tumors

    OpenAIRE

    2008-01-01

    In recent years there has been a flood of interest in the relationship between brain tumors and stem cells. Some investigators have focused on the sensitivity of normal stem cells to transformation, others have described phenotypic or functional similarities between tumor cells and stem cells, and still others have suggested that tumors contain a subpopulation of “cancer stem cells” that is crucial for tumor maintenance or propagation. While all these concepts are interesting and provide insi...

  8. Milrinone in Enterovirus 71 Brain Stem Encephalitis

    Science.gov (United States)

    Wang, Shih-Min

    2016-01-01

    Enterovirus 71 (EV71) was implicated in a widespread outbreak of hand-foot-and-mouth disease (HFMD) across the Asia Pacific area since 1997 and has also been reported sporadically in patients with brain stem encephalitis. Neurogenic shock with pulmonary edema (PE) is a fatal complication of EV71 infection. Among inotropic agents, milrinone is selected as a therapeutic agent for EV71- induced PE due to its immunopathogenesis. Milrinone is a type III phosphodiesterase inhibitor that has both inotropic and vasodilator effects. Its clinical efficacy has been shown by modulating inflammation, reducing sympathetic over-activity, and improving survival in patients with EV71-associated PE. Milrinone exhibits immunoregulatory and anti-inflammatory effects in the management of systemic inflammatory responses in severe EV71 infection. PMID:27065870

  9. Milrinone in Enterovirus 71 Brain Stem Encephalitis

    Directory of Open Access Journals (Sweden)

    SHIH-MIN eWANG

    2016-03-01

    Full Text Available Enterovirus 71 (EV71 was implicated in a widespread outbreak of hand-foot-and-mouth disease (HFMD across the Asia Pacific area since 1997 and has also been reported sporadically in patients with brain stem encephalitis. Neurogenic shock with pulmonary edema (PE is a fatal complication of EV71 infection. Among inotropic agents, milrinone is selected as a therapeutic agent for EV71- induced PE due to its immunopathogenesis. Milrinone is a type III phosphodiesterase inhibitor that has both inotropic and vasodilator effects. Its clinical efficacy has been shown by modulating inflammation, reducing sympathetic over-activity, and improving survival in patients with EV71-associated PE. Milrinone exhibits immunoregulatory and anti-inflammatory effects in the management of systemic inflammatory responses in severe EV71 infection.

  10. Referências anatômicas na cirurgia do implante auditivo de tronco cerebral Anatomical landmarks in auditory brainstem implant surgery

    Directory of Open Access Journals (Sweden)

    Rubens Vuono Brito Neto

    2005-06-01

    Full Text Available O implante auditivo de tronco cerebral é uma opção os pacientes surdos que não têm a integridade das vias auditivas preservada. A cirurgia, por sua complexidade anatômica e funcional, requer treinamento específico em laboratório de anatomia por parte do cirurgião. OBJETIVOS: Estudar a anatomia cirúrgica da cirurgia do implante auditivo de tronco cerebral. FORMA DE ESTUDO: Estudo anatômico. MATERIAL E MÉTODO: Neste estudo dissecamos cadáver fresco preparado com solução corante injetada nas artérias e veias intra-cranianas. O local de inserção do eletrodo do implante auditivo de tronco cerebral foi estudado através do acesso translabiríntico. RESULTADOS: A técnica cirúrgica utilizada para a implantação do eletrodo de tronco cerebral é semelhante à utilizada na remoção do shwannoma vestibular. O complexo de núcleo coclear, composto pelo núcleo coclear ventral e dorsal, é o local para a colocação do eletrodo. O núcleo coclear ventral é o principal núcleo de transmissão de impulsos neurais do VIII par e seus axônios formam a principal via ascendente do nervo coclear. Tanto o núcleo ventral como o dorsal não são visíveis durante a cirurgia e sua localização depende de identificação de estruturas anatômicas adjacentes. CONCLUSÃO: A região de implantação do eletrodo do implante auditivo de tronco cerebral apresenta referências anatômicas que permitem sua fácil identificação durante a cirurgia.Auditory brainstem implant (ABI is an option for deaf patients who do not have the whole auditory pathways preserved. The surgery, because of its anatomical and functional complexity, requires specific training of the surgeon in an anatomy lab. AIM: To study the surgical anatomy of the auditory brainstem implant surgery. STUDY DESIGN: Anatomic study. MATERIAL AND METHOD: In the present study, we dissected a fresh cadaver prepared with a dye solution injected into the arteries and intracranial veins. The

  11. Discrimination of timbre in early auditory responses of the human brain.

    Directory of Open Access Journals (Sweden)

    Jaeho Seol

    Full Text Available BACKGROUND: The issue of how differences in timbre are represented in the neural response still has not been well addressed, particularly with regard to the relevant brain mechanisms. Here we employ phasing and clipping of tones to produce auditory stimuli differing to describe the multidimensional nature of timbre. We investigated the auditory response and sensory gating as well, using by magnetoencephalography (MEG. METHODOLOGY/PRINCIPAL FINDINGS: Thirty-five healthy subjects without hearing deficit participated in the experiments. Two different or same tones in timbre were presented through conditioning (S1-testing (S2 paradigm as a pair with an interval of 500 ms. As a result, the magnitudes of auditory M50 and M100 responses were different with timbre in both hemispheres. This result might support that timbre, at least by phasing and clipping, is discriminated in the auditory early processing. The second response in a pair affected by S1 in the consecutive stimuli occurred in M100 of the left hemisphere, whereas both M50 and M100 responses to S2 only in the right hemisphere reflected whether two stimuli in a pair were the same or not. Both M50 and M100 magnitudes were different with the presenting order (S1 vs. S2 for both same and different conditions in the both hemispheres. CONCLUSIONS/SIGNIFICANCES: Our results demonstrate that the auditory response depends on timbre characteristics. Moreover, it was revealed that the auditory sensory gating is determined not by the stimulus that directly evokes the response, but rather by whether or not the two stimuli are identical in timbre.

  12. Brain state-dependent abnormal LFP activity in the auditory cortex of a schizophrenia mouse model.

    Science.gov (United States)

    Nakao, Kazuhito; Nakazawa, Kazu

    2014-01-01

    In schizophrenia, evoked 40-Hz auditory steady-state responses (ASSRs) are impaired, which reflects the sensory deficits in this disorder, and baseline spontaneous oscillatory activity also appears to be abnormal. It has been debated whether the evoked ASSR impairments are due to the possible increase in baseline power. GABAergic interneuron-specific NMDA receptor (NMDAR) hypofunction mutant mice mimic some behavioral and pathophysiological aspects of schizophrenia. To determine the presence and extent of sensory deficits in these mutant mice, we recorded spontaneous local field potential (LFP) activity and its click-train evoked ASSRs from primary auditory cortex of awake, head-restrained mice. Baseline spontaneous LFP power in the pre-stimulus period before application of the first click trains was augmented at a wide range of frequencies. However, when repetitive ASSR stimuli were presented every 20 s, averaged spontaneous LFP power amplitudes during the inter-ASSR stimulus intervals in the mutant mice became indistinguishable from the levels of control mice. Nonetheless, the evoked 40-Hz ASSR power and their phase locking to click trains were robustly impaired in the mutants, although the evoked 20-Hz ASSRs were also somewhat diminished. These results suggested that NMDAR hypofunction in cortical GABAergic neurons confers two brain state-dependent LFP abnormalities in the auditory cortex; (1) a broadband increase in spontaneous LFP power in the absence of external inputs, and (2) a robust deficit in the evoked ASSR power and its phase-locking despite of normal baseline LFP power magnitude during the repetitive auditory stimuli. The "paradoxically" high spontaneous LFP activity of the primary auditory cortex in the absence of external stimuli may possibly contribute to the emergence of schizophrenia-related aberrant auditory perception.

  13. Brain state-dependent abnormal LFP activity in the auditory cortex of a schizophrenia mouse model

    Directory of Open Access Journals (Sweden)

    Kazuhito eNakao

    2014-07-01

    Full Text Available In schizophrenia, evoked 40-Hz auditory steady-state responses (ASSRs are impaired, which reflects the sensory deficits in this disorder, and baseline spontaneous oscillatory activity also appears to be abnormal. It has been debated whether the evoked ASSR impairments are due to the possible increase in baseline power. GABAergic interneuron-specific NMDA receptor (NMDAR hypofunction mutant mice mimic some behavioral and pathophysiological aspects of schizophrenia. To determine the presence and extent of sensory deficits in these mutant mice, we recorded spontaneous local field potential (LFP activity and its click-train evoked ASSRs from primary auditory cortex of awake, head-restrained mice. Baseline spontaneous LFP power in the pre-stimulus period before application of the first click trains was augmented at a wide range of frequencies. However, when repetitive ASSR stimuli were presented every 20 sec, averaged spontaneous LFP power amplitudes during the inter-ASSR stimulus intervals in the mutant mice became indistinguishable from the levels of control mice. Nonetheless, the evoked 40-Hz ASSR power and their phase locking to click trains were robustly impaired in the mutants, although the evoked 20-Hz ASSRs were also somewhat diminished. These results suggested that NMDAR hypofunction in cortical GABAergic neurons confers two brain state-dependent LFP abnormalities in the auditory cortex; (1 a broadband increase in spontaneous LFP power in the absence of external inputs, and (2 a robust deficit in the evoked ASSR power and its phase-locking despite of normal baseline LFP power magnitude during the repetitive auditory stimuli. The paradoxically high spontaneous LFP activity of the primary auditory cortex in the absence of external stimuli may possibly contribute to the emergence of schizophrenia-related aberrant auditory perception.

  14. Anesthesia mumps resulting in temporary facial nerve paralysis after the auditory brainstem implantation in a 3-year-old child.

    Science.gov (United States)

    Özdek, Ali; Bayır, Ömer; Işık, Murat Eray; Tatar, Emel Çadallı; Saylam, Güleser; Korkmaz, Hakan

    2014-01-01

    An acute transient sialadenitis of the major salivary glands in the early postoperative period is called 'anesthesia mumps'. It has been reported in different surgical procedures especially in neurosurgical procedures. Anesthesia mumps develops very fast after the extubation period but it usually regresses with no sequelae within a few hours. However, sometimes serious complication can occur such as respiratory distress. In this report, we present a 3-year-old girl with an anesthesia mumps and facial palsy occurring after successful auditory brainstem implantation and we discuss the cause and the management of this rare complication in this report.

  15. Long-term results of external auditory canal closure and mastoid obliteration in cochlear implantation after radical mastoidectomy: a clinical and radiological study.

    Science.gov (United States)

    Vincenti, Vincenzo; Pasanisi, Enrico; Bacciu, Andrea; Bacciu, Salvatore

    2014-08-01

    Cochlear implant candidates with mastoid cavity present a significant challenge to safe cochlear implantation because of possible spread of infection to the inner ear as well as an increased risk of electrode array extrusion. Closure of the external auditory canal is one of the several surgical techniques utilized to block the potential entry routes for infection and to protect the implanted device. The main concern after external auditory canal closure is the risk of developing a cholesteatoma, which can lead to an asymptomatic erosion of the temporal bone and/or cochlear implant failure. In this study we present the results of very long-term (mean 12 years) clinical and radiological follow-up in 12 patients who underwent external auditory canal closure associated with mastoid and Eustachian tube obliteration to facilitate cochlear implantation. To date, with a mean ± SD follow-up of 12 ± 4.7 years (range 5-21 years), the only complication experienced was the breakdown of the EAC closure in one patient, successfully treated by performing a rotation skin flap. The results of this study confirmed that external auditory canal closure is a reliable technique in cochlear implantation after radical mastoidectomy provided that a rigorous surgical technique is performed. A right balance between the need to reduce costs and to avoid unnecessary doses of radiation to patients and the task of a radiological surveillance may be represented by performing computed tomography 12-18 months postoperatively and then, only if clinically warranted.

  16. Acoustic emissions from the inner ear and brain stem responses in type 2 diabetics

    Directory of Open Access Journals (Sweden)

    Jabbari Moghaddam Y

    2011-12-01

    Full Text Available Yalda Jabbari MoghaddamDepartment of Otolaryngology, Head and Neck Surgery, Tabriz University of Medical Sciences, Tabriz, IranBackground: The purpose of this study was to evaluate the auditory brain stem response (ABR and acoustic emissions of the inner ear (OAE in middle-aged type 2 diabetics.Methods: Fifty type 2 diabetic and nondiabetic patients aged 40–50 years and attending the Tabriz Medical University outpatient clinics were recruited for this study during 2009–2010. All ABR and OAE procedures were implemented by an audiometrist. The relationship between ABR and OAE findings and demographic, laboratory, and clinical characteristics was investigated.Results: Fifty patients (34 female and 16 male of average age 45.7 ± 3.0 years were entered into the study. In the type 2 diabetic group, disordered ABR was found in at least one ear in 8% of cases and disordered OAE was recorded in at least one ear in 16% of cases, with no significant difference between the diabetic and nondiabetic groups. Mean age, duration of diabetes, serum HbA1c levels, and prevalence of female gender were higher in the diabetic group.Conclusion: According to our findings, the prevalence of ABR and OAE is not significantly different between type 2 diabetics and nondiabetics.Keywords: sensorineural hearing loss, diabetes, auditory brain stem response, otoacoustic emission

  17. A vision-free brain-computer interface (BCI) paradigm based on auditory selective attention.

    Science.gov (United States)

    Kim, Do-Won; Cho, Jae-Hyun; Hwang, Han-Jeong; Lim, Jeong-Hwan; Im, Chang-Hwan

    2011-01-01

    Majority of the recently developed brain computer interface (BCI) systems have been using visual stimuli or visual feedbacks. However, the BCI paradigms based on visual perception might not be applicable to severe locked-in patients who have lost their ability to control their eye movement or even their vision. In the present study, we investigated the feasibility of a vision-free BCI paradigm based on auditory selective attention. We used the power difference of auditory steady-state responses (ASSRs) when the participant modulates his/her attention to the target auditory stimulus. The auditory stimuli were constructed as two pure-tone burst trains with different beat frequencies (37 and 43 Hz) which were generated simultaneously from two speakers located at different positions (left and right). Our experimental results showed high classification accuracies (64.67%, 30 commands/min, information transfer rate (ITR) = 1.89 bits/min; 74.00%, 12 commands/min, ITR = 2.08 bits/min; 82.00%, 6 commands/min, ITR = 1.92 bits/min; 84.33%, 3 commands/min, ITR = 1.12 bits/min; without any artifact rejection, inter-trial interval = 6 sec), enough to be used for a binary decision. Based on the suggested paradigm, we implemented a first online ASSR-based BCI system that demonstrated the possibility of materializing a totally vision-free BCI system.

  18. Targeting breast to brain metastatic tumours with death receptor ligand expressing therapeutic stem cells.

    Science.gov (United States)

    Bagci-Onder, Tugba; Du, Wanlu; Figueiredo, Jose-Luiz; Martinez-Quintanilla, Jordi; Shah, Khalid

    2015-06-01

    Characterizing clinically relevant brain metastasis models and assessing the therapeutic efficacy in such models are fundamental for the development of novel therapies for metastatic brain cancers. In this study, we have developed an in vivo imageable breast-to-brain metastasis mouse model. Using real time in vivo imaging and subsequent composite fluorescence imaging, we show a widespread distribution of micro- and macro-metastasis in different stages of metastatic progression. We also show extravasation of tumour cells and the close association of tumour cells with blood vessels in the brain thus mimicking the multi-foci metastases observed in the clinics. Next, we explored the ability of engineered adult stem cells to track metastatic deposits in this model and show that engineered stem cells either implanted or injected via circulation efficiently home to metastatic tumour deposits in the brain. Based on the recent findings that metastatic tumour cells adopt unique mechanisms of evading apoptosis to successfully colonize in the brain, we reasoned that TNF receptor superfamily member 10A/10B apoptosis-inducing ligand (TRAIL) based pro-apoptotic therapies that induce death receptor signalling within the metastatic tumour cells might be a favourable therapeutic approach. We engineered stem cells to express a tumour selective, potent and secretable variant of a TRAIL, S-TRAIL, and show that these cells significantly suppressed metastatic tumour growth and prolonged the survival of mice bearing metastatic breast tumours. Furthermore, the incorporation of pro-drug converting enzyme, herpes simplex virus thymidine kinase, into therapeutic S-TRAIL secreting stem cells allowed their eradication post-tumour treatment. These studies are the first of their kind that provide insight into targeting brain metastasis with stem-cell mediated delivery of pro-apoptotic ligands and have important clinical implications.

  19. Can you hear me now? Musical training shapes functional brain networks for selective auditory attention and hearing speech in noise

    Directory of Open Access Journals (Sweden)

    Dana L Strait

    2011-06-01

    Full Text Available Even in the quietest of rooms, our senses are perpetually inundated by a barrage of sounds, requiring the auditory system to adapt to a variety of listening conditions in order to extract signals of interest (e.g., one speaker’s voice amidst others. Brain networks that promote selective attention are thought to sharpen the neural encoding of a target signal, suppressing competing sounds and enhancing perceptual performance. Here, we ask: does musical training benefit cortical mechanisms that underlie selective attention to speech? To answer this question, we assessed the impact of selective auditory attention on cortical auditory-evoked response variability in musicians and nonmusicians. Outcomes indicate strengthened brain networks for selective auditory attention in musicians in that musicians but not nonmusicians demonstrate decreased prefrontal response variability with auditory attention. Results are interpreted in the context of previous work from our laboratory documenting perceptual and subcortical advantages in musicians for the hearing and neural encoding of speech in background noise. Musicians’ neural proficiency for selectively engaging and sustaining auditory attention to language indicates a potential benefit of music for auditory training. Given the importance of auditory attention for the development of language-related skills, musical training may aid in the prevention, habilitation and remediation of children with a wide range of attention-based language and learning impairments.

  20. Evaluation of implant-materials as cell carriers for dental stem cells under in vitro conditions

    OpenAIRE

    Gosau, Martin; Viale-Bouroncle, Sandra; Eickhoff, Hannah; Prateeptongkum, Esthera; Reck, Anja; Götz, W.; Klingelhöffer, Christoph; Müller, Steffen; Morsczeck, Christian

    2015-01-01

    Background Dental stem cells in combination with implant materials may become an alternative to autologous bone transplants. For tissue engineering different types of soft and rigid implant materials are available, but little is known about the viability and the osteogenic differentiation of dental stem cells on these different types of materials. According to previous studies we proposed that rigid bone substitute materials are superior to soft materials for dental tissue engineering. Method...

  1. The use of auditory and visual context in speech perception by listeners with normal hearing and listeners with cochlear implants

    Directory of Open Access Journals (Sweden)

    Matthew eWinn

    2013-11-01

    Full Text Available There is a wide range of acoustic and visual variability across different talkers and different speaking contexts. Listeners with normal hearing accommodate that variability in ways that facilitate efficient perception, but it is not known whether listeners with cochlear implants can do the same. In this study, listeners with normal hearing (NH and listeners with cochlear implants (CIs were tested for accommodation to auditory and visual phonetic contexts created by gender-driven speech differences as well as vowel coarticulation and lip rounding in both consonants and vowels. Accommodation was measured as the shifting of perceptual boundaries between /s/ and /ʃ/ sounds in various contexts, as modeled by mixed-effects logistic regression. Owing to the spectral contrasts thought to underlie these context effects, CI listeners were predicted to perform poorly, but showed considerable success. Listeners with cochlear implants not only showed sensitivity to auditory cues to gender, they were also able to use visual cues to gender (i.e. faces as a supplement or proxy for information in the acoustic domain, in a pattern that was not observed for listeners with normal hearing. Spectrally-degraded stimuli heard by listeners with normal hearing generally did not elicit strong context effects, underscoring the limitations of noise vocoders and/or the importance of experience with electric hearing. Visual cues for consonant lip rounding and vowel lip rounding were perceived in a manner consistent with coarticulation and were generally used more heavily by listeners with CIs. Results suggest that listeners with cochlear implants are able to accommodate various sources of acoustic variability either by attending to appropriate acoustic cues or by inferring them via the visual signal.

  2. Neurosyphilis Involving Cranial Nerves in Brain Stem: 2 Case Reports

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Ji Hye [Dept. of Radiology, Kyung Hee University College of Medicine, Seoul (Korea, Republic of); Choi, Woo Suk; Kim, Eui Jong [Dept. of Radiology, Kyung Hee University Hospital, Seoul (Korea, Republic of); Yoon, Sung Sang; Heo, Sung Hyuk [Dept. of Neurology, Kyung Hee University Hospital, Seoul (Korea, Republic of)

    2012-01-15

    Neurosyphilis uncommonly presents with cranial neuropathies in acute syphilitic meningitis and meningovascular neurosyphilis. We now report two cases in which the meningeal form of neurosyphilis involved cranial nerves in the brain stem: the oculomotor and trigeminal nerve.

  3. The WIN-Speller: A new Intuitive Auditory Brain-Computer Interface Spelling Application

    Directory of Open Access Journals (Sweden)

    Sonja C Kleih

    2015-10-01

    Full Text Available The objective of this study was to test the usability of a new auditory Brain-Computer Interface (BCI application for communication. We introduce a word based, intuitive auditory spelling paradigm the WIN-speller. In the WIN-speller letters are grouped by words, such as the word KLANG representing the letters A, G, K, L and N. Thereby, the decoding step between perceiving a code and translating it to the stimuli it represents becomes superfluous. We tested 11 healthy volunteers and 4 end-users with motor impairment in the copy spelling mode. Spelling was successful with an average accuracy of 84% in the healthy sample. Three of the end-users communicated with average accuracies of 80% or higher while one user was not able to communicate reliably. Even though further evaluation is required, the WIN-speller represents a potential alternative for BCI based communication in end-users.

  4. Differential maturation of brain signal complexity in the human auditory and visual system

    Directory of Open Access Journals (Sweden)

    Sarah Lippe

    2009-11-01

    Full Text Available Brain development carries with it a large number of structural changes at the local level which impact on the functional interactions of distributed neuronal networks for perceptual processing. Such changes enhance information processing capacity, which can be indexed by estimation of neural signal complexity. Here, we show that during development, EEG signal complexity increases from one month to 5 years of age in response to auditory and visual stimulation. However, the rates of change in complexity were not equivalent for the two responses. Infants’ signal complexity for the visual condition was greater than auditory signal complexity, whereas adults showed the same level of complexity to both types of stimuli. The differential rates of complexity change may reflect a combination of innate and experiential factors on the structure and function of the two sensory systems.

  5. Neurotrophic treatment of the degenerating auditory nerve; cochlear implants in deafened guinea pigs

    NARCIS (Netherlands)

    Agterberg, M.J.H.

    2009-01-01

    To date, the cochlear implant is the most successful sensorineural prosthesis. The device consists of a small array with a number of electrodes implanted in the cochlea of profoundly hearing impaired people. Some people with an implant are able to use the telephone. Unfortunately, others hardly bene

  6. Training stem cells for treatment of malignant brain tumors

    Institute of Scientific and Technical Information of China (English)

    Shengwen; Calvin; Li; Mustafa; H; Kabeer; Long; T; Vu; Vic; Keschrumrus; Hong; Zhen; Yin; Brent; A; Dethlefs; Jiang; F; Zhong; John; H; Weiss; William; G; Loudon

    2014-01-01

    The treatment of malignant brain tumors remains a challenge. Stem cell technology has been applied in the treatment of brain tumors largely because of the ability of some stem cells to infiltrate into regions within the brain where tumor cells migrate as shown in preclinical studies. However, not all of these efforts can translate in the effective treatment that improves the quality of life for pa-tients. Here, we perform a literature review to identify the problems in the field. Given the lack of efficacy of most stem cell-based agents used in the treatment of malignant brain tumors, we found that stem cell distribution(i.e., only a fraction of stem cells applied capable of targeting tumors) are among the limiting factors. We provide guidelines for potential improvements in stem cell distribution. Specifically, we use an engineered tissue graft platform that replicates the in vivo microenvironment, and provide our data to validate that this culture platform is viable for producing stem cells that have better stem cell distribution than with the Petri dish culture system.

  7. Effects of the body temperature on the synthetic wave of electrocochleogram and brain stem auditory evoked potentials in guinea pigs%体温对豚鼠耳蜗电图-脑干听觉诱发电位综合波的影响

    Institute of Scientific and Technical Information of China (English)

    何斯纯; 马宁; 周卓妍; 周丽丽

    2005-01-01

    背景:脑干听觉诱发电位(brainstem auditory evoked potentials,BAEP)和耳蜗电图(electrocochleogram,ECochG)两者综合波的新记录方法具有特殊临床意义,探讨体温升高和体温降低对其的影响对进一步明确ECochG-BAEP综合波的生理特性和指导其临床应用有重要意义.目的:观察体温升高和体温降低对ECochG-BAEP综合波的影响效应.设计:随机区组设计.单位:暨南大学医学院生理教研室.对象:实验于2002-07/09在暨南大学医学院生理学教研室进行,选择成年豚鼠(300~350 g),雌雄不拘,由第一军医大学动物实验中心提供,随机分为体温降低组(20只)和体温升高组(20只).干预:体温降低组,体表物理降温法逐步降低豚鼠体温;体温升高组,体表物理升温法逐步升高豚鼠体温.主要观察指标:ECochG-BAEP综合波的波形、波峰潜伏期(PL)、波峰间潜伏期(IPL)和波幅随体温发生的变化.结果:随体温降低(36~25℃)和体温升高(36~42℃),ECochG-BAEP综合波波形始终兼具BAEP和ECochG两者的特点,有十分明显突出的1波;各波PL和IPL随体温降低而逐步延长,但随体温升高而逐渐缩短;1,2,3波波幅在体温降低至30~29℃时开始出现显著降低,1,2波波幅也在体温升高至40℃后开始出现显著降低.结论:体温降低和体温升高对ECochG-BAEP SW的PL,IPL和波幅均有显著影响,但其波形始终兼具BAEP和ECochG两者的特点.%BACKGROUND: A new method for recording the synthetic wave of electrocochleogram-brain stem auditory evoked potentials(ECochG-BAEP SW)has special clinical significance. The study of effects of hypothermia and hyperthermia on the synthetic wave is significant to define its physiological properties and to guide its clinical application.OBJECTIVE: To observe the effects of hypothermia and hyperthermia on ECochG-BAEP SW.DESIGN: A randomized block design.SETTING: Department of Physiology, Medical College of Jinan University

  8. The biomechanical effect of anteversion and modular neck offset on stress shielding for short-stem versus conventional long-stem hip implants.

    Science.gov (United States)

    Goshulak, Peter; Samiezadeh, Saeid; Aziz, Mina S R; Bougherara, Habiba; Zdero, Radovan; Schemitsch, Emil H

    2016-03-01

    Short-stem hip implants are increasingly common since they preserve host bone stock and presumably reduce stress shielding by improving load distribution in the proximal femur. Stress shielding may lead to decreased bone density, implant loosening, and fracture. However, few biomechanical studies have examined short-stem hip implants. The purpose of this study was to compare short-stem vs. standard length stemmed implants for stress shielding effects due to anteversion-retroversion, anterior-posterior position, and modular neck offset. Twelve artificial femurs were implanted with either a short-stem modular-neck implant or a conventional length monolithic implant in 0° or 15° of anteversion. Three modular neck options were tested in the short-stem implants. Three control femurs remained intact. Femurs were mounted in adduction and subjected to axial loading. Strain gauge values were collected to validate a Finite Element (FE) model, which was used to simulate the full range of physiologically possible anteversion and anterior-posterior combinations (n = 25 combinations per implant). Calcar stress was compared between implants and across each implant's range of anteversion using one and two-way ANOVA. Stress shielding was defined as the overall change in stress compared to an intact femur. The FE model compared well with experimental strains (intact: slope = 0.898, R = 0.943; short-stem: slope = 0.731, R = 0.948; standard-stem: slope = 0.743, R = 0.859); correction factors were used to adjust slopes to unity. No implant anteversion showed significant reduction in stress shielding (α = 0.05, p > 0.05). Stress shielding was significantly higher in the standard-stem implant (63% change from intact femur, p < 0.001) than in short-stem implants (29-39% change, p < 0.001). Short-stem implants reduce stress shielding compared to standard length stemmed implants, while implant anteversion and anterior-posterior position had no effect. Therefore, short-stem implants have

  9. Mesenchymal Stem Cell Transplantation Attenuates Brain Injury After Neonatal Stroke

    NARCIS (Netherlands)

    van Velthoven, Cindy T. J.; Sheldon, R. Ann; Kavelaars, Annemieke; Derugin, Nikita; Vexler, Zinaida S.; Willemen, Hanneke L. D. M.; Maas, Mirjam; Heijnen, Cobi J.; Ferriero, Donna M.

    2013-01-01

    Background and Purpose-Brain injury caused by stroke is a frequent cause of perinatal morbidity and mortality with limited therapeutic options. Mesenchymal stem cells (MSC) have been shown to improve outcome after neonatal hypoxic-ischemic brain injury mainly by secretion of growth factors stimulati

  10. A glucose fuel cell for implantable brain-machine interfaces.

    Directory of Open Access Journals (Sweden)

    Benjamin I Rapoport

    Full Text Available We have developed an implantable fuel cell that generates power through glucose oxidation, producing 3.4 μW cm(-2 steady-state power and up to 180 μW cm(-2 peak power. The fuel cell is manufactured using a novel approach, employing semiconductor fabrication techniques, and is therefore well suited for manufacture together with integrated circuits on a single silicon wafer. Thus, it can help enable implantable microelectronic systems with long-lifetime power sources that harvest energy from their surrounds. The fuel reactions are mediated by robust, solid state catalysts. Glucose is oxidized at the nanostructured surface of an activated platinum anode. Oxygen is reduced to water at the surface of a self-assembled network of single-walled carbon nanotubes, embedded in a Nafion film that forms the cathode and is exposed to the biological environment. The catalytic electrodes are separated by a Nafion membrane. The availability of fuel cell reactants, oxygen and glucose, only as a mixture in the physiologic environment, has traditionally posed a design challenge: Net current production requires oxidation and reduction to occur separately and selectively at the anode and cathode, respectively, to prevent electrochemical short circuits. Our fuel cell is configured in a half-open geometry that shields the anode while exposing the cathode, resulting in an oxygen gradient that strongly favors oxygen reduction at the cathode. Glucose reaches the shielded anode by diffusing through the nanotube mesh, which does not catalyze glucose oxidation, and the Nafion layers, which are permeable to small neutral and cationic species. We demonstrate computationally that the natural recirculation of cerebrospinal fluid around the human brain theoretically permits glucose energy harvesting at a rate on the order of at least 1 mW with no adverse physiologic effects. Low-power brain-machine interfaces can thus potentially benefit from having their implanted units

  11. Brain stem hypoplasia associated with Cri-du-Chat syndrome.

    Science.gov (United States)

    Hong, Jin Ho; Lee, Ha Young; Lim, Myung Kwan; Kim, Mi Young; Kang, Young Hye; Lee, Kyung Hee; Cho, Soon Gu

    2013-01-01

    Cri-du-Chat syndrome, also called the 5p-syndrome, is a rare genetic abnormality, and only few cases have been reported on its brain MRI findings. We describe the magnetic resonance imaging findings of a 1-year-old girl with Cri-du-Chat syndrome who showed brain stem hypoplasia, particularly in the pons, with normal cerebellum and diffuse hypoplasia of the cerebral hemispheres. We suggest that Cri-du-Chat syndrome chould be suspected in children with brain stem hypoplasia, particularly for those with high-pitched cries.

  12. Brain stem hypoplasia associated with Cri-du-Chat syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jin Ho; Lee, Ha Young; Lim, Myung Kwan; Kim, Mi Young; Kang, Young Hye; Lee, Kyung Hee; Cho, Soon Gu [Dept. of Radiology, Inha University Hospital, Inha University School of Medicine, Incheon (Korea, Republic of)

    2013-12-15

    Cri-du-Chat syndrome, also called the 5p-syndrome, is a rare genetic abnormality, and only few cases have been reported on its brain MRI findings. We describe the magnetic resonance imaging findings of a 1-year-old girl with Cri-du-Chat syndrome who showed brain stem hypoplasia, particularly in the pons, with normal cerebellum and diffuse hypoplasia of the cerebral hemispheres. We suggest that Cri-du-Chat syndrome chould be suspected in children with brain stem hypoplasia, particularly for those with high-pitched cries.

  13. Brain responses to altered auditory feedback during musical keyboard production: an fMRI study.

    Science.gov (United States)

    Pfordresher, Peter Q; Mantell, James T; Brown, Steven; Zivadinov, Robert; Cox, Jennifer L

    2014-03-27

    Alterations of auditory feedback during piano performance can be profoundly disruptive. Furthermore, different alterations can yield different types of disruptive effects. Whereas alterations of feedback synchrony disrupt performed timing, alterations of feedback pitch contents can disrupt accuracy. The current research tested whether these behavioral dissociations correlate with differences in brain activity. Twenty pianists performed simple piano keyboard melodies while being scanned in a 3-T magnetic resonance imaging (MRI) scanner. In different conditions they experienced normal auditory feedback, altered auditory feedback (asynchronous delays or altered pitches), or control conditions that excluded movement or sound. Behavioral results replicated past findings. Neuroimaging data suggested that asynchronous delays led to increased activity in Broca's area and its right homologue, whereas disruptive alterations of pitch elevated activations in the cerebellum, area Spt, inferior parietal lobule, and the anterior cingulate cortex. Both disruptive conditions increased activations in the supplementary motor area. These results provide the first evidence of neural responses associated with perception/action mismatch during keyboard production.

  14. Simultaneous EEG-fMRI brain signatures of auditory cue utilization

    Directory of Open Access Journals (Sweden)

    Mathias eScharinger

    2014-06-01

    Full Text Available Optimal utilization of acoustic cues during auditory categorization is a vital skill, particularly when informative cues become occluded or degraded. Consequently, the acoustic environment requires flexible choosing and switching amongst available cues. The present study targets the brain functions underlying such changes in cue utilization. Participants performed a categorization task with immediate feedback on acoustic stimuli from two categories that varied in duration and spectral properties, while we simultaneously recorded Blood Oxygenation Level Dependent (BOLD responses in fMRI and electroencephalograms (EEGs. In the first half of the experiment, categories could be best discriminated by spectral properties. Halfway through the experiment, spectral degradation rendered the stimulus duration the more informative cue. Behaviorally, degradation decreased the likelihood of utilizing spectral cues. Spectrally degrading the acoustic signal led to increased alpha power compared to nondegraded stimuli. The EEG-informed fMRI analyses revealed that alpha power correlated with BOLD changes in inferior parietal cortex and right posterior superior temporal gyrus (including planum temporale. In both areas, spectral degradation led to a weaker coupling of BOLD response to behavioral utilization of the spectral cue. These data provide converging evidence from behavioral modeling, electrophysiology, and hemodynamics that (a increased alpha power mediates the inhibition of uninformative (here spectral stimulus features, and that (b the parietal attention network supports optimal cue utilization in auditory categorization. The results highlight the complex cortical processing of auditory categorization under realistic listening challenges.

  15. A Femur-Implant Model for the Prediction of Bone Remodeling Behavior Induced by Cementless Stem

    Institute of Scientific and Technical Information of China (English)

    He Gong; Lingyan Kong; Rui Zhang; Juan Fang; Meisheng Zhao

    2013-01-01

    Bone remodeling simulation is an effective tool for the prediction of long-term effect of implant on the bone tissue,as well as the selection of an appropriate implant in terms of architecture and material.In this paper,a finite element model of proximal femur was develop.ed to simulate the structures of internal trabecular and cortical bones by incorporating quantitative bone functional adaptation theory with finite element analysis.Cementless stems made of titanium,two types of Functionally Graded Material (FGM) and flexible 'iso-elastic' material as comparison were implanted in the structure of proximal femur respectively to simulate the bone remodeling behaviors of host bone.The distributions of bone density,von Mises stress,and interface shear stress were obtained.All the prosthetic stems had effects on the bone remodeling behaviors of proximal femur,but the degrees of stress shielding were different.The amount of bone loss caused by titanium implant was in agreement with the clinical observation.The FGM stems caused less bone loss than that of the titanium stem,in which FGM I stem (titanium richer at the top to more HAP/Col towards the bottom) could relieve stress shielding effectively,and the interface shear stresses were more evenly distributed in the model with FGM I stem in comparison with those in the models with FGM II (titanium and bioglass) and titanium stems.The numerical simulations in the present study provided theoretical basis for FGM as an appropriate material of femoral implant from a biomechanical point of view.The next steps are to fabricate FGM stem and to conduct animal experiments to investigate the effects of FGM stem on the remodeling behaviors using animal model.

  16. Brain activity underlying auditory perceptual learning during short period training: simultaneous fMRI and EEG recording

    OpenAIRE

    2013-01-01

    Abstract Background There is an accumulating body of evidence indicating that neuronal functional specificity to basic sensory stimulation is mutable and subject to experience. Although fMRI experiments have investigated changes in brain activity after relative to before perceptual learning, brain activity during perceptual learning has not been explored. This work investigated brain activity related to auditory frequency discrimination learning using a variational Bayesian approach for sourc...

  17. Are there fetal stem cells in the maternal brain?

    Institute of Scientific and Technical Information of China (English)

    Osman Demirhan; Necmi (C)ekin; Deniz Ta(s)temir; Erdal Tun(c); Ali irfan Güzel; Demet Meral; Bülent Demirbek

    2013-01-01

    Fetal cells can enter maternal blood during pregnancy but whether they can also cross the blood-brain barrier to enter the maternal brain remains poorly understood. Previous results suggest that fetal cells are summoned to repair damage to the mother's brain. If this is confirmed, it would open up new and safer avenues of treatment for brain damage caused by strokes and neural diseases. In this study, we aimed to investigate whether a baby's stem cells can enter the maternal brain during pregnancy. Deceased patients who had at least one male offspring and no history of abortion and blood transfusion were included in this study. DNA was extracted from brain tissue samples of deceased women using standard phenol-chloroform extraction and ethanol precipitation methods. Genomic DNA was screened by quantitative fluorescent-polymerase chain reaction amplification together with short tandem repeat markers specific to the Y chromosome, and 13, 18, 21 and X. Any foreign DNA residues that could be used to interpret the presence of fetal stem cells in the maternal brain were monitored. Results indicated that fetal stem cells can not cross the blood-brain barrier to enter the maternal brain.

  18. The short stem GHEs in total hip replacement – experience after 380 implantations

    Directory of Open Access Journals (Sweden)

    Ghanem, Mohamed

    2013-11-01

    Full Text Available Introduction: Standard straight stems have been recognized as a gold standard implant in the field of hip replacement surgery. However, lately uncemented bone-preserving short stems started to gain more and more popularity. This was reflected in the increasing variety of available models. Up till now, short and mid-term results are available.Patients and methods: In 2002, the cementless short stemmed GHEs was introduced. 380 patients were included in our study between 2002 and 2008. Only GHEs short stems were implanted. The clinical and radiological evaluations were performed in the Orthopaedic Department, Leipzig University Hospitals, on the average of 24 months (3 to 60 months postoperatively.Results: 365 primary implantations and 15 revision implantations were carried out. Average age 60 years. Favourable clinical and radiological outcome was seen in 361/380 patients (95%. Postoperative complications were seen in 19/380 patients (5%: 8 fissures/fractures (2.1%, 5 infections (1.3%, 4 aseptic loosenings (1.1%, 2 dislocations (0.5%.Conclusions: Short stem implants, including our own experience with GHEs model, are satisfying and promising. They represent a valuable supplementation of the treatment modalities in hip replacement surgery. However, long term results are still awaited.

  19. Influence of Thickness and Contact Surface Geometry of Condylar Stem of TMJ Implant on Its Stability

    Science.gov (United States)

    Arabshahi, Zohreh; Kashani, Jamal; Kadir, Mohammed Rafiq Abdul; Azari, Abbas

    The aim of this study is to examine the effect thickness and contact surface geometry of condylar stem of TMJ implant on its stability in total reconstruction system and evaluate the micro strain resulted in bone at fixation screw holes in jaw bone embedded with eight different designs of temporomandibular joint implants. A three dimensional model of a lower mandible of an adult were developed from a Computed Tomography scan images. Eight different TMJ implant designs and fixation screws were modeled. Three dimensional finite element models of eight implanted mandibles were analyzed. The forces assigned to the masticatory muscles for incisal clenching were applied consisting of nine important muscular loads. In chosen loading condition, The results indicated that the anatomical curvature contact surface design of TMJ implant can moderately improve the stability and the strain resulted in fixation screw holes in thinner TMJ implant was diminished in comparison with other thicknesses.

  20. Increasing infection rate in multiple implanted pulse generator changes in movement disorder patients treated with deep brain stimulation

    DEFF Research Database (Denmark)

    Thrane, Jens F; Sunde, Niels A; Bergholt, Bo

    2014-01-01

    Increasing infection rate in multiple implanted pulse generator changes in movement disorder patients treated with deep brain stimulation......Increasing infection rate in multiple implanted pulse generator changes in movement disorder patients treated with deep brain stimulation...

  1. Synaptic proteome changes in mouse brain regions upon auditory discrimination learning.

    Science.gov (United States)

    Kähne, Thilo; Kolodziej, Angela; Smalla, Karl-Heinz; Eisenschmidt, Elke; Haus, Utz-Uwe; Weismantel, Robert; Kropf, Siegfried; Wetzel, Wolfram; Ohl, Frank W; Tischmeyer, Wolfgang; Naumann, Michael; Gundelfinger, Eckart D

    2012-08-01

    Changes in synaptic efficacy underlying learning and memory processes are assumed to be associated with alterations of the protein composition of synapses. Here, we performed a quantitative proteomic screen to monitor changes in the synaptic proteome of four brain areas (auditory cortex, frontal cortex, hippocampus striatum) during auditory learning. Mice were trained in a shuttle box GO/NO-GO paradigm to discriminate between rising and falling frequency modulated tones to avoid mild electric foot shock. Control-treated mice received corresponding numbers of either the tones or the foot shocks. Six hours and 24 h later, the composition of a fraction enriched in synaptic cytomatrix-associated proteins was compared to that obtained from naïve mice by quantitative mass spectrometry. In the synaptic protein fraction obtained from trained mice, the average percentage (±SEM) of downregulated proteins (59.9 ± 0.5%) exceeded that of upregulated proteins (23.5 ± 0.8%) in the brain regions studied. This effect was significantly smaller in foot shock (42.7 ± 0.6% down, 40.7 ± 1.0% up) and tone controls (43.9 ± 1.0% down, 39.7 ± 0.9% up). These data suggest that learning processes initially induce removal and/or degradation of proteins from presynaptic and postsynaptic cytoskeletal matrices before these structures can acquire a new, postlearning organisation. In silico analysis points to a general role of insulin-like signalling in this process.

  2. Utilising reinforcement learning to develop strategies for driving auditory neural implants

    Science.gov (United States)

    Lee, Geoffrey W.; Zambetta, Fabio; Li, Xiaodong; Paolini, Antonio G.

    2016-08-01

    Objective. In this paper we propose a novel application of reinforcement learning to the area of auditory neural stimulation. We aim to develop a simulation environment which is based off real neurological responses to auditory and electrical stimulation in the cochlear nucleus (CN) and inferior colliculus (IC) of an animal model. Using this simulator we implement closed loop reinforcement learning algorithms to determine which methods are most effective at learning effective acoustic neural stimulation strategies. Approach. By recording a comprehensive set of acoustic frequency presentations and neural responses from a set of animals we created a large database of neural responses to acoustic stimulation. Extensive electrical stimulation in the CN and the recording of neural responses in the IC provides a mapping of how the auditory system responds to electrical stimuli. The combined dataset is used as the foundation for the simulator, which is used to implement and test learning algorithms. Main results. Reinforcement learning, utilising a modified n-Armed Bandit solution, is implemented to demonstrate the model’s function. We show the ability to effectively learn stimulation patterns which mimic the cochlea’s ability to covert acoustic frequencies to neural activity. Time taken to learn effective replication using neural stimulation takes less than 20 min under continuous testing. Significance. These results show the utility of reinforcement learning in the field of neural stimulation. These results can be coupled with existing sound processing technologies to develop new auditory prosthetics that are adaptable to the recipients current auditory pathway. The same process can theoretically be abstracted to other sensory and motor systems to develop similar electrical replication of neural signals.

  3. Implants and Decoding for Intracortical Brain Computer Interfaces

    Science.gov (United States)

    Homer, Mark L.; Nurmikko, Arto V.; Donoghue, John P.; Hochberg, Leigh R.

    2014-01-01

    Intracortical brain computer interfaces (iBCIs) are being developed to enable a person to drive an output device, such as a computer cursor, directly from their neural activity. One goal of the technology is to help people with severe paralysis or limb loss. Key elements of an iBCI are the implanted sensor that records the neural signals and the software which decodes the user’s intended movement from those signals. Here, we focus on recent advances in these two areas, with special attention being placed on contributions that are or may soon be adopted by the iBCI research community. We discuss how these innovations increase the technology’s capability, accuracy, and longevity, all important steps that are expanding the range of possible future clinical applications. PMID:23862678

  4. Oral Implant-Prostheses: New Teeth for a Brighter Brain

    Science.gov (United States)

    De Cicco, Vincenzo; Barresi, Massimo; Tramonti Fantozzi, Maria Paola; Cataldo, Enrico; Parisi, Vincenzo; Manzoni, Diego

    2016-01-01

    Several studies have demonstrated that chewing can be regarded as a preventive measure for cognitive impairment, whereas masticatory deficiency, associated with soft-diet feeding, is a risk factor for the development of dementia. At present the link between orofacial sensorimotor activity and cognitive functions is unknown. In subjects with unilateral molar loss we have shown asymmetries in both pupil size and masticatory muscles electromyographic (EMG) activity during clenching: the molar less side was characterized by a lower EMG activity and a smaller pupil. Since implant-prostheses, greatly reduced both the asymmetry in EMG activity and in pupil’s size, trigeminal unbalance, leading to unbalance in the activity of the Locus Coeruleus (LC), may be responsible for the pupil’s asymmetry. According to the findings obtained in animal models, we propose that the different activity of the right and left LC may induce an asymmetry in brain activity, thus leading to cognitive impairment. According to this hypothesis, prostheses improved the performance in a complex sensorimotor task and increased the mydriasis associated with haptic tasks. In conclusion, the present study indicates that the implant-prosthesis therapy, which reduces the unbalance of trigeminal proprioceptive afferents and the asymmetry in pupil’s size, may improve arousal, boosting performance in a complex sensorimotor task. PMID:26919258

  5. Oral Implant-Prostheses: New Teeth for a Brighter Brain.

    Directory of Open Access Journals (Sweden)

    Vincenzo De Cicco

    Full Text Available Several studies have demonstrated that chewing can be regarded as a preventive measure for cognitive impairment, whereas masticatory deficiency, associated with soft-diet feeding, is a risk factor for the development of dementia. At present the link between orofacial sensorimotor activity and cognitive functions is unknown. In subjects with unilateral molar loss we have shown asymmetries in both pupil size and masticatory muscles electromyographic (EMG activity during clenching: the molar less side was characterized by a lower EMG activity and a smaller pupil. Since implant-prostheses, greatly reduced both the asymmetry in EMG activity and in pupil's size, trigeminal unbalance, leading to unbalance in the activity of the Locus Coeruleus (LC, may be responsible for the pupil's asymmetry. According to the findings obtained in animal models, we propose that the different activity of the right and left LC may induce an asymmetry in brain activity, thus leading to cognitive impairment. According to this hypothesis, prostheses improved the performance in a complex sensorimotor task and increased the mydriasis associated with haptic tasks. In conclusion, the present study indicates that the implant-prosthesis therapy, which reduces the unbalance of trigeminal proprioceptive afferents and the asymmetry in pupil's size, may improve arousal, boosting performance in a complex sensorimotor task.

  6. 水杨酸钠对幼年和成年豚鼠听性脑干反应阈值及螺旋神经节谷氨酸脱羧酶表达的影响%Effect of sodium salicylate on the auditory brain stem response threshold and expression of glutamic acid decarboxylase in spiral ganglion of juvenile and adult guinea pigs

    Institute of Scientific and Technical Information of China (English)

    尹时华; 唐安洲; 谭颂华; 陈平; 谢利红; 任毅

    2008-01-01

    目的 观察水杨酸钠对幼年和成年豚鼠听性脑干反应(ABR)阈值以及螺旋神经节谷氨酸脱羧酶(glutamic acid decarboxylase,GAD)表达的影响.方法 选择出生4 d的豚鼠40只和出生后1个月的成年豚鼠40只,分成4组(每组20只):幼年对照组,成年对照组,幼年水杨酸钠给药组[300 mg/(kg·d)],成年水杨酸钠给药组[300 mg/(kg·d)].给药15 d后每组随机选取10只豚鼠检测ABR阈值,采用免疫组织化学染色方法检测螺旋神经节GAD的表达.各组剩下的动物停止给药,继续喂养30 d后检测ABR阈值和螺旋神经节GAD的表达.结果 给药15 d后幼年水杨酸钠给药组和成年水杨酸钠给药组豚鼠ABR阈值较给药前以及同期对照组均有提高(P值均<0.001),停药30 d后幼年水杨酸钠给药组ABR阈值恢复到给药前水平,而成年水杨酸钠给药组仍停留在高阈值水平;水杨酸钠给药15 d后能明显下调幼年以及成年豚鼠螺旋神经节GAD蛋白表达,幼年豚鼠GAD表达水平低于成年豚鼠(t=4.7,P<0.001),停药30 d后幼年给药组螺旋神经节GAD表达恢复到同期对照组水平,而成年给药组则继续停留在低表达水平.结论 水杨酸钠在对幼年和成年豚鼠ABR阚值以及螺旋神经节GAD表达的影响上存在差异,其对幼年豚鼠的影响更为明显,但停药后幼年豚鼠较成年豚鼠更容易恢复到正常水平.%Objective To study the differences of regulation of sodium salicylate on the auditory brain stem response(ABR)threshold and expression of glutamic acid decarboxylase(GAD)protein in spiral ganglion of juvenile and adult guinea pigs.Methods Fourty juvenile guinea pigs which were born just four days and fourty adult guinea pigs which were born thirty days were selected.They were divided four groups (group A;group B;group C;group D).ABR threshold was detected before administration.after administration for 15 days and after administration stopped for 30 days.The protein expression of GAD

  7. Drosophila neural stem cells in brain development and tumor formation.

    Science.gov (United States)

    Jiang, Yanrui; Reichert, Heinrich

    2014-01-01

    Neuroblasts, the neural stem cells in Drosophila, generate the complex neural structure of the central nervous system. Significant progress has been made in understanding the mechanisms regulating the self-renewal, proliferation, and differentiation in Drosophila neuroblast lineages. Deregulation of these mechanisms can lead to severe developmental defects and the formation of malignant brain tumors. Here, the authors review the molecular genetics of Drosophila neuroblasts and discuss some recent advances in stem cell and cancer biology using this model system.

  8. Enhanced peripheral visual processing in congenitally deaf humans is supported by multiple brain regions, including primary auditory cortex.

    Science.gov (United States)

    Scott, Gregory D; Karns, Christina M; Dow, Mark W; Stevens, Courtney; Neville, Helen J

    2014-01-01

    Brain reorganization associated with altered sensory experience clarifies the critical role of neuroplasticity in development. An example is enhanced peripheral visual processing associated with congenital deafness, but the neural systems supporting this have not been fully characterized. A gap in our understanding of deafness-enhanced peripheral vision is the contribution of primary auditory cortex. Previous studies of auditory cortex that use anatomical normalization across participants were limited by inter-subject variability of Heschl's gyrus. In addition to reorganized auditory cortex (cross-modal plasticity), a second gap in our understanding is the contribution of altered modality-specific cortices (visual intramodal plasticity in this case), as well as supramodal and multisensory cortices, especially when target detection is required across contrasts. Here we address these gaps by comparing fMRI signal change for peripheral vs. perifoveal visual stimulation (11-15° vs. 2-7°) in congenitally deaf and hearing participants in a blocked experimental design with two analytical approaches: a Heschl's gyrus region of interest analysis and a whole brain analysis. Our results using individually-defined primary auditory cortex (Heschl's gyrus) indicate that fMRI signal change for more peripheral stimuli was greater than perifoveal in deaf but not in hearing participants. Whole-brain analyses revealed differences between deaf and hearing participants for peripheral vs. perifoveal visual processing in extrastriate visual cortex including primary auditory cortex, MT+/V5, superior-temporal auditory, and multisensory and/or supramodal regions, such as posterior parietal cortex (PPC), frontal eye fields, anterior cingulate, and supplementary eye fields. Overall, these data demonstrate the contribution of neuroplasticity in multiple systems including primary auditory cortex, supramodal, and multisensory regions, to altered visual processing in congenitally deaf adults.

  9. Os resultados do implante coclear em crianças portadoras de Neuropatia Auditiva: revisão de literatura The results of cochlear implants in children with Auditory Neuropathy: literature review

    Directory of Open Access Journals (Sweden)

    Rafaela Carolina Lopez Silva

    2007-09-01

    Full Text Available A Neuropatia Auditiva é um distúrbio na condução do estímulo sonoro, provavelmente relacionado à alteração da mielinização das fibras do nervo auditivo. Os avanços tecnológicos têm levado ao aumento nos recursos de diagnóstico e intervenção nos casos de deficiência auditiva por etiologia de Neuropatia Auditiva. O objetivo do presente estudo foi pesquisar na literatura os resultados obtidos em crianças com Neuropatia Auditiva após implante coclear. Foi realizado um trabalho de revisão bibliográfica em livros, periódicos e internet dos últimos dez anos sobre crianças com Neuropatia Auditiva usuárias de implante coclear. As pesquisas sugerem que a estimulação elétrica é capaz de compensar a dessincronia do nervo e que o implante coclear é um recurso para a (rehabilitação da audição em crianças portadoras de Neuropatia Auditiva. O uso do implante coclear permite melhoria significativa nas habilidades da audição e da comunicação. No entanto, as habilidades adquiridas parecem sofrer influência de diversos fatores como: tempo de uso do dispositivo, existência de um processo terapêutico sistemático, época do diagnóstico e a idade da criança.Auditory Neuropathy is a disorder in the transmission of the sound stimulus, probably related to mielinization alterations of auditory nerve fibers. Technology advances have been increasing diagnostic and intervention resources in cases of hearing loss caused by auditory neuropathy. The aim of the present study was to research the available literature about the results obtained with children with Auditory Neuropathy after cochlear implants. An ample review was conducted on books, articles and the internet, over the last 10 years, regarding children with Auditory Neuropathy, users of cochlear implants. The available data suggest that electric stimulation can compensate neural asynchrony and that cochlear implants aid in the rehabilitation process of children with Auditory

  10. 小鼠胚胎干细胞移植入成体大鼠脑内的区域特异性存活与分化%Regionspecific survival and differentiation of mouse embryonic stem cell-derived implants in the adult rat brain

    Institute of Scientific and Technical Information of China (English)

    鲁文果; 陈红; 王东; 黎逢光; 张苏明

    2007-01-01

    Totipotent and regionally non-specified embryonic stem (ES) cells provide a powerful tool to understand mechanisms controlling stem cell differentiation in different regions of the adult brain. As the development capacity of ES cells in the adult brain is still largely unknown, we grafted small amounts of mouse ES (mES) cells into adult rat brains to explore the survival and differentiation of implanted mES cells in different rat brain regions. We transplanted the green fluorescent protein (GFP)-positive mES cells into the hippocampus, septal area, cortex and caudate nucleus in rat brains. Then the rats were sacrificed 5,14 and 28 d later. Of all the brain regions, the survival rate of the transplanted cells and their progeny were the highest in the hippocampus and the lowest in the septal area (P<0.01). The grafted ES cells could differentiate into nestin-positive neural stem cells. Nestin-positive/GFP-positive cells were observed in all brain regions with the highest frequency of nestin-positive cells in the hippocampus and the lowest in the medial septal area (P<0.01). mES cells differentiated into end cells such as neurons and glial cells in all transplantation sites in recipient brains. In the hippocampus, the ES cells differentiated into neurons in large amounts. These results demonstrate that only some brain regions permit survival of mES cells and their progeny, and form instructive environments for neuronal differentiation of mES cells. Thus, because of regionspecific presence of microenvironmental cues and their environmental fields, the characteristics of the recipient tissue were considerably important in formulating cell replacement strategies for neural disorders.%全能区域非特异性的胚胎干细胞是研究成体不同脑区控制干细胞分化能力的十分有力的工具.胚胎干细胞源性神经前体细胞移植入成体脑后可分化为功能性神经元,但是未分化的胚胎干细胞在成体脑内各个部位的存活、生

  11. Human Brain Stem Structures Respond Differentially to Noxious Heat

    Directory of Open Access Journals (Sweden)

    Alexander eRitter

    2013-09-01

    Full Text Available Concerning the physiological correlates of pain, the brain stem is considered to be one core region that is activated by noxious input. In animal studies, different slopes of skin heating (SSH with noxious heat led to activation in different columns of the midbrain periaqueductal grey (PAG. The present study aimed at finding a method for differentiating structures in PAG and other brain stem structures, which are associated with different qualities of pain in humans according to the structures that were associated with different behavioral significances to noxious thermal stimulation in animals. Brain activity was studied by fMRI in healthy subjects in response to steep and shallow SSH with noxious heat. We found differential activation to different SSH in the PAG and the rostral ventromedial medulla (RVM. In a second experiment we demonstrate that the different SSH were associated with different pain qualities. Our experiments provide evidence that brainstem structures, i.e. the PAG and the RVM, become differentially activated by different SSH. Therefore, different SSH can be utilized when brain stem structures are investigated and when it is aimed to activate these structures differentially. Moreover, percepts of first pain were elicited by shallow SSH whereas percepts of second pain were elicited by steep SSH. The stronger activation of these brain stem structures to SSH, eliciting percepts of second vs. first pain, might be of relevance for activating different coping strategies in response to the noxious input with the two types of SSH.

  12. 听觉植入的研发和临床应用进展%The Research and Clinical Application of Auditory Implants

    Institute of Scientific and Technical Information of China (English)

    杨仕明; 申卫东; 曾凡钢

    2011-01-01

    @@ 1听觉植入技术的介绍 人工耳蜗是听觉植入装置(auditory implant,auditory prosthesis)的代表,截至2009年4月,全世界已经有超过18.8万人在使用这种装置(U.S.Food and Drug Administration),人工耳蜗成为最成功的神经植入假体(neuroprosthetics)[1,2].

  13. Noise Trauma Induced Plastic Changes in Brain Regions outside the Classical Auditory Pathway

    Science.gov (United States)

    Chen, Guang-Di; Sheppard, Adam; Salvi, Richard

    2017-01-01

    The effects of intense noise exposure on the classical auditory pathway have been extensively investigated; however, little is known about the effects of noise-induced hearing loss on non-classical auditory areas in the brain such as the lateral amygdala (LA) and striatum (Str). To address this issue, we compared the noise-induced changes in spontaneous and tone-evoked responses from multiunit clusters (MUC) in the LA and Str with those seen in auditory cortex (AC). High-frequency octave band noise (10–20 kHz) and narrow band noise (16–20 kHz) induced permanent thresho ld shifts (PTS) at high-frequencies within and above the noise band but not at low frequencies. While the noise trauma significantly elevated spontaneous discharge rate (SR) in the AC, SRs in the LA and Str were only slightly increased across all frequencies. The high-frequency noise trauma affected tone-evoked firing rates in frequency and time dependent manner and the changes appeared to be related to severity of noise trauma. In the LA, tone-evoked firing rates were reduced at the high-frequencies (trauma area) whereas firing rates were enhanced at the low-frequencies or at the edge-frequency dependent on severity of hearing loss at the high frequencies. The firing rate temporal profile changed from a broad plateau to one sharp, delayed peak. In the AC, tone-evoked firing rates were depressed at high frequencies and enhanced at the low frequencies while the firing rate temporal profiles became substantially broader. In contrast, firing rates in the Str were generally decreased and firing rate temporal profiles become more phasic and less prolonged. The altered firing rate and pattern at low frequencies induced by high frequency hearing loss could have perceptual consequences. The tone-evoked hyperactivity in low-frequency MUC could manifest as hyperacusis whereas the discharge pattern changes could affect temporal resolution and integration. PMID:26701290

  14. Exploring combinations of auditory and visual stimuli for gaze-independent brain-computer interfaces.

    Directory of Open Access Journals (Sweden)

    Xingwei An

    Full Text Available For Brain-Computer Interface (BCI systems that are designed for users with severe impairments of the oculomotor system, an appropriate mode of presenting stimuli to the user is crucial. To investigate whether multi-sensory integration can be exploited in the gaze-independent event-related potentials (ERP speller and to enhance BCI performance, we designed a visual-auditory speller. We investigate the possibility to enhance stimulus presentation by combining visual and auditory stimuli within gaze-independent spellers. In this study with N = 15 healthy users, two different ways of combining the two sensory modalities are proposed: simultaneous redundant streams (Combined-Speller and interleaved independent streams (Parallel-Speller. Unimodal stimuli were applied as control conditions. The workload, ERP components, classification accuracy and resulting spelling speed were analyzed for each condition. The Combined-speller showed a lower workload than uni-modal paradigms, without the sacrifice of spelling performance. Besides, shorter latencies, lower amplitudes, as well as a shift of the temporal and spatial distribution of discriminative information were observed for Combined-speller. These results are important and are inspirations for future studies to search the reason for these differences. For the more innovative and demanding Parallel-Speller, where the auditory and visual domains are independent from each other, a proof of concept was obtained: fifteen users could spell online with a mean accuracy of 87.7% (chance level <3% showing a competitive average speed of 1.65 symbols per minute. The fact that it requires only one selection period per symbol makes it a good candidate for a fast communication channel. It brings a new insight into the true multisensory stimuli paradigms. Novel approaches for combining two sensory modalities were designed here, which are valuable for the development of ERP-based BCI paradigms.

  15. STATIC AND DYNAMIC POSTURE CONTROL IN POSTLINGUAL COCHLEAR IMPLANTED PATIENTS: Effects of dual-tasking, visual and auditory inputs suppression

    Directory of Open Access Journals (Sweden)

    BERNARD DEMANZE eLaurence

    2014-01-01

    Full Text Available Posture control is based on central integration of multisensory inputs, and on internal representation of body orientation in space. This multisensory feedback regulates posture control and continuously updates the internal model of body’s position which in turn forwards motor commands adapted to the environmental context and constraints. The peripheral localization of the vestibular system, close to the cochlea, makes vestibular damage possible following cochlear implant (CI surgery. Impaired vestibular function in CI patients, if any, may have a strong impact on posture stability. The simple postural task of quiet standing is generally paired with cognitive activity in most day life conditions, leading therefore to competition for attentional resources in dual-tasking, and increased risk of fall particularly in patients with impaired vestibular function. This study was aimed at evaluating the effects of post-lingual cochlear implantation on posture control in adult deaf patients. Possible impairment of vestibular function was assessed by comparing the postural performance of patients to that of age-matched healthy subjects during a simple postural task performed in static and dynamic conditions, and during dual-tasking with a visual or auditory memory task. Postural tests were done in eyes open (EO and eyes closed (EC conditions, with the cochlear implant activated (ON or not (OFF. Results showed that the CI patients significantly reduced limits of stability and increased postural instability in static conditions. In dynamic conditions, they spent considerably more energy to maintain equilibrium, and their head was stabilized neither in space nor on trunk while the controls showed a whole body rigidification strategy. Hearing (prosthesis on as well as dual-tasking did not really improve the dynamic postural performance of the CI patients. We conclude that CI patients become strongly visual dependent mainly in challenging postural conditions.

  16. The robo-pigeon based on the multiple brain regions synchronization implanted microelectrodes.

    Science.gov (United States)

    Huai, Rui-Tuo; Yang, Jun-Qing; Wang, Hui

    2016-07-03

    Almost all multichannel microelectrodes are only applied to the same nucleus. The multiple brain regions synchronization implanted microelectrodes can be implanted in the several brain regions at the same time, when used in the robo-animal, which can reduce the operation process, shorten animals operation time. Due to electrode position relatively fixed, errors caused by each separately implanted electrode were reduced and the animal control effect was greatly increased compared to the original electrodes. The electrode fixed time was also extended. This microelectrode provided beneficial reference function for the study of the free state of small animals in different brain regions.

  17. Modeling Stem/Progenitor Cell-Induced Neovascularization and Oxygenation Around Solid Implants

    KAUST Repository

    Jain, Harsh Vardhan

    2012-07-01

    Tissue engineering constructs and other solid implants with biomedical applications, such as drug delivery devices or bioartificial organs, need oxygen (O(2)) to function properly. To understand better the vascular integration of such devices, we recently developed a novel model sensor containing O(2)-sensitive crystals, consisting of a polymeric capsule limited by a nanoporous filter. The sensor was implanted in mice with hydrogel alone (control) or hydrogel embedded with mouse CD117/c-kit+ bone marrow progenitor cells in order to stimulate peri-implant neovascularization. The sensor provided local partial O(2) pressure (pO(2)) using noninvasive electron paramagnetic resonance signal measurements. A consistently higher level of peri-implant oxygenation was observed in the cell-treatment case than in the control over a 10-week period. To provide a mechanistic explanation of these experimental observations, we present in this article a mathematical model, formulated as a system of coupled partial differential equations, that simulates peri-implant vascularization. In the control case, vascularization is considered to be the result of a foreign body reaction, while in the cell-treatment case, adipogenesis in response to paracrine stimuli produced by the stem cells is assumed to induce neovascularization. The model is validated by fitting numerical predictions of local pO(2) to measurements from the implanted sensor. The model is then used to investigate further the potential for using stem cell treatment to enhance the vascular integration of biomedical implants. We thus demonstrate how mathematical modeling combined with experimentation can be used to infer how vasculature develops around biomedical implants in control and stem cell-treated cases.

  18. Syrinx of the Spinal Cord and Brain Stem

    Science.gov (United States)

    ... Prompt Healthier Eating Scientists Working on Solar-Powered Prosthetic Limbs Health Highlights: March 23, 2017 Fruit Juice for Kids: A Serving a Day OK ALL NEWS > Resources ... may extend downward to affect the entire cord. Syrinxes that extend into or begin in the lower part of the brain stem may compress pathways ...

  19. Mapping the calcitonin receptor in human brain stem

    DEFF Research Database (Denmark)

    Bower, Rebekah L; Eftekhari, Sajedeh; Waldvogel, Henry J

    2016-01-01

    understanding of these hormone systems by mapping CTR expression in the human brain stem, specifically the medulla oblongata. Widespread CTR-like immunoreactivity was observed throughout the medulla. Dense CTR staining was noted in several discrete nuclei, including the nucleus of the solitary tract...

  20. Incorporating modern neuroscience findings to improve brain-computer interfaces: tracking auditory attention

    Science.gov (United States)

    Wronkiewicz, Mark; Larson, Eric; Lee, Adrian KC

    2016-10-01

    Objective. Brain-computer interface (BCI) technology allows users to generate actions based solely on their brain signals. However, current non-invasive BCIs generally classify brain activity recorded from surface electroencephalography (EEG) electrodes, which can hinder the application of findings from modern neuroscience research. Approach. In this study, we use source imaging—a neuroimaging technique that projects EEG signals onto the surface of the brain—in a BCI classification framework. This allowed us to incorporate prior research from functional neuroimaging to target activity from a cortical region involved in auditory attention. Main results. Classifiers trained to detect attention switches performed better with source imaging projections than with EEG sensor signals. Within source imaging, including subject-specific anatomical MRI information (instead of using a generic head model) further improved classification performance. This source-based strategy also reduced accuracy variability across three dimensionality reduction techniques—a major design choice in most BCIs. Significance. Our work shows that source imaging provides clear quantitative and qualitative advantages to BCIs and highlights the value of incorporating modern neuroscience knowledge and methods into BCI systems.

  1. Auditory pathway functioning in prelingual deafness : The clinical consequences for cochlear implantation

    NARCIS (Netherlands)

    Lammers, M.J.W.

    2015-01-01

    Cochlear implantation has proven itself as a very successful treatment for both children and adults with severe to profound hearing loss. Although most patients obtain a high level of speech perception, performance is more variable in prelingually deaf patients, i.e., patients with an onset of sever

  2. AUDITORY REHABILITATION AND BILATERAL COCHLEAR IMPLANT ON CHILD WHITH CEREBRAL PALSY

    Directory of Open Access Journals (Sweden)

    Anacléia Melo da Silva Hilgenberg

    2013-01-01

    Full Text Available OBJECTIVE: To describe the hearing and language improvement in children with cerebral palsy submitted to cochlear implantation bilaterally. METHODS: Prospective, analytical descriptive. Study case and a broad bibliographical analysis in MEDLINE/PUBMED and EMBASE including detailed analysis of the rehabilitation techniques as serial phonoaudiological appointments; Sessions of phonoterapy recorded and criterious analysis of the tests such as IT-MAIS and MacArthur analysis. The teste were applied after Bilateral Cochlear Implantation: 15, 20, 22, 31 e 38 months.RESULTS: The results obtained and bibliographical analysis showed that cochlear implantation in children with cerebral palsy and profound hearing loss is the best option at the moment to perform hearing rehabilitation. The IT-MAIS and MacArthur tests showed a big improvement at 15 and 38 months after use of the cochlear implants. The IT-MAIS test showed 40% score in the beggining and 75% at the end. Mac Arthur test revealed a big evolution at vocabulary comprehension (58 to 342 and linguistic repertory (54 to 289.

  3. A Stem Cell-Seeded Nanofibrous Scaffold for Auditory Nerve Replacement

    Science.gov (United States)

    2013-10-01

    biopolymer scaffold within the internal auditory meatus (IAM) of the guinea pig. (A) The lateral wall of an intact guinea pig temporal bone is shown......Nanofibrous Scaffold for Auditory Nerve Replacement 5b. GRANT NUMBER W81XWH-12-1-0492 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Betty Diamond

  4. Resolving the neural dynamics of visual and auditory scene processing in the human brain: a methodological approach

    Science.gov (United States)

    Teng, Santani

    2017-01-01

    In natural environments, visual and auditory stimulation elicit responses across a large set of brain regions in a fraction of a second, yielding representations of the multimodal scene and its properties. The rapid and complex neural dynamics underlying visual and auditory information processing pose major challenges to human cognitive neuroscience. Brain signals measured non-invasively are inherently noisy, the format of neural representations is unknown, and transformations between representations are complex and often nonlinear. Further, no single non-invasive brain measurement technique provides a spatio-temporally integrated view. In this opinion piece, we argue that progress can be made by a concerted effort based on three pillars of recent methodological development: (i) sensitive analysis techniques such as decoding and cross-classification, (ii) complex computational modelling using models such as deep neural networks, and (iii) integration across imaging methods (magnetoencephalography/electroencephalography, functional magnetic resonance imaging) and models, e.g. using representational similarity analysis. We showcase two recent efforts that have been undertaken in this spirit and provide novel results about visual and auditory scene analysis. Finally, we discuss the limits of this perspective and sketch a concrete roadmap for future research. This article is part of the themed issue ‘Auditory and visual scene analysis’. PMID:28044019

  5. Growth hormone (GH), brain development and neural stem cells.

    Science.gov (United States)

    Waters, M J; Blackmore, D G

    2011-12-01

    A range of observations support a role for GH in development and function of the brain. These include altered brain structure in GH receptor null mice, and impaired cognition in GH deficient rodents and in a subgroup of GH receptor defective patients (Laron dwarfs). GH has been shown to alter neurogenesis, myelin synthesis and dendritic branching, and both the GH receptor and GH itself are expressed widely in the brain. We have found a population of neural stem cells which are activated by GH infusion, and which give rise to neurons in mice. These stem cells are activated by voluntary exercise in a GH-dependent manner. Given the findings that local synthesis of GH occurs in the hippocampus in response to a memory task, and that GH replacement improves memory and cognition in rodents and humans, these new observations warrant a reappraisal of the clinical importance of GH replacement in GH deficient states.

  6. Preliminary Studies on Differential Expression of Auditory Functional Genes in the Brain After Repeated Blast Exposures

    Science.gov (United States)

    2012-01-01

    Army Medical Research and Materiel Command, Fort Detrick, MD Abstract—The mechanisms of central auditory processing involved in auditory/ vestibular ...trans- ducers in auditory neurons [22–23,45–48]. The frontal cor- tex and midbrain of blast-exposed mice showed significant increase in the expression of...auditory neurons [26]. Other types of molecules involved in calcium regula- tion, such as calreticulin and calmodulin-dependent pro- tein kinase expression

  7. A living thick nanofibrous implant bifunctionalized with active growth factor and stem cells for bone regeneration

    Directory of Open Access Journals (Sweden)

    Eap S

    2015-02-01

    Full Text Available Sandy Eap,1,2,* Laetitia Keller,1–3,* Jessica Schiavi,1,2 Olivier Huck,1,2 Leandro Jacomine,4 Florence Fioretti,1,2 Christian Gauthier,4 Victor Sebastian,1,3,5 Pascale Schwinté,1,2 Nadia Benkirane-Jessel1,21INSERM, UMR 1109, Osteoarticular and Dental Regenerative Nanomedicine Laboratory, FMTS, Faculté de Médecine, Strasbourg, France; 2Faculté de Chirurgie Dentaire, Université de Strasbourg, Strasbourg, France; 3Department of Chemical Engineering, Aragon Nanoscience Institute, University of Zaragoza, Zaragoza, Spain; 4CNRS (National Center for Scientific Research, ICS (Charles Sadron Institute, Strasbourg, France; 5Networking Research Center of Bioengineering, Biomaterials and Nanomedicine, Zaragoza, Spain*These authors contributed equally to this workAbstract: 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

  8. Descending brain neurons in the cricket Gryllus bimaculatus (de Geer): auditory responses and impact on walking.

    Science.gov (United States)

    Zorović, Maja; Hedwig, Berthold

    2013-01-01

    The activity of four types of sound-sensitive descending brain neurons in the cricket Gryllus bimaculatus was recorded intracellularly while animals were standing or walking on an open-loop trackball system. In a neuron with a contralaterally descending axon, the male calling song elicited responses that copied the pulse pattern of the song during standing and walking. The accuracy of pulse copying increased during walking. Neurons with ipsilaterally descending axons responded weakly to sound only during standing. The responses were mainly to the first pulse of each chirp, whereas the complete pulse pattern of a chirp was not copied. During walking the auditory responses were suppressed in these neurons. The spiking activity of all four neuron types was significantly correlated to forward walking velocity, indicating their relevance for walking. Additionally, injection of depolarizing current elicited walking and/or steering in three of four neuron types described. In none of the neurons was the spiking activity both sufficient and necessary to elicit and maintain walking behaviour. Some neurons showed arborisations in the lateral accessory lobes, pointing to the relevance of this brain region for cricket audition and descending motor control.

  9. Synchrony of auditory brain responses predicts behavioral ability to keep still in children with autism spectrum disorder

    Directory of Open Access Journals (Sweden)

    Yuko Yoshimura

    2016-01-01

    Full Text Available The auditory-evoked P1m, recorded by magnetoencephalography, reflects a central auditory processing ability in human children. One recent study revealed that asynchrony of P1m between the right and left hemispheres reflected a central auditory processing disorder (i.e., attention deficit hyperactivity disorder, ADHD in children. However, to date, the relationship between auditory P1m right-left hemispheric synchronization and the comorbidity of hyperactivity in children with autism spectrum disorder (ASD is unknown. In this study, based on a previous report of an asynchrony of P1m in children with ADHD, to clarify whether the P1m right-left hemispheric synchronization is related to the symptom of hyperactivity in children with ASD, we investigated the relationship between voice-evoked P1m right-left hemispheric synchronization and hyperactivity in children with ASD. In addition to synchronization, we investigated the right-left hemispheric lateralization. Our findings failed to demonstrate significant differences in these values between ASD children with and without the symptom of hyperactivity, which was evaluated using the Autism Diagnostic Observational Schedule, Generic (ADOS-G subscale. However, there was a significant correlation between the degrees of hemispheric synchronization and the ability to keep still during 12-minute MEG recording periods. Our results also suggested that asynchrony in the bilateral brain auditory processing system is associated with ADHD-like symptoms in children with ASD.

  10. Brain responses to musical feature changes in adolescent cochlear implant users.

    Science.gov (United States)

    Petersen, Bjørn; Weed, Ethan; Sandmann, Pascale; Brattico, Elvira; Hansen, Mads; Sørensen, Stine Derdau; Vuust, Peter

    2015-01-01

    Cochlear implants (CIs) are primarily designed to assist deaf individuals in perception of speech, although possibilities for music fruition have also been documented. Previous studies have indicated the existence of neural correlates of residual music skills in postlingually deaf adults and children. However, little is known about the behavioral and neural correlates of music perception in the new generation of prelingually deaf adolescents who grew up with CIs. With electroencephalography (EEG), we recorded the mismatch negativity (MMN) of the auditory event-related potential to changes in musical features in adolescent CI users and in normal-hearing (NH) age mates. EEG recordings and behavioral testing were carried out before (T1) and after (T2) a 2-week music training program for the CI users and in two sessions equally separated in time for NH controls. We found significant MMNs in adolescent CI users for deviations in timbre, intensity, and rhythm, indicating residual neural prerequisites for musical feature processing. By contrast, only one of the two pitch deviants elicited an MMN in CI users. This pitch discrimination deficit was supported by behavioral measures, in which CI users scored significantly below the NH level. Overall, MMN amplitudes were significantly smaller in CI users than in NH controls, suggesting poorer music discrimination ability. Despite compliance from the CI participants, we found no effect of the music training, likely resulting from the brevity of the program. This is the first study showing significant brain responses to musical feature changes in prelingually deaf adolescent CI users and their associations with behavioral measures, implying neural predispositions for at least some aspects of music processing. Future studies should test any beneficial effects of a longer lasting music intervention in adolescent CI users.

  11. Brain Responses to Musical Feature Changes in Adolescent Cochlear Implant Users

    Directory of Open Access Journals (Sweden)

    Bjørn ePetersen

    2015-02-01

    Full Text Available Cochlear implants (CIs are primarily designed to assist deaf individuals in perception of speech, although possibilities for music fruition have also been documented. Previous studies have indicated the existence of neural correlates of residual music skills in postlingually deaf adults and children. However, little is known about the behavioral and neural correlates of music perception in the new generation of prelingually deaf adolescents who grew up with CIs. With electroencephalography (EEG, we recorded the mismatch negativity (MMN of the auditory event-related potential (ERP to changes in musical features in adolescent CI users and in normal-hearing age mates. EEG recordings and behavioral testing were carried out before (T1 and after (T2 a 2-week music training program for the CI users and in two sessions equally separated in time for normal-hearing (NH controls. We found significant MMNs in adolescent CI users for deviations in timbre, intensity and rhythm, indicating residual neural prerequisites for musical feature processing. By contrast, only one of the two pitch deviants elicited an MMN in CI users. This pitch discrimination deficit was supported by behavioral measures, in which CI users scored significantly below the NH level. Overall MMN amplitudes were significantly smaller in CI users than in NH controls, suggesting poorer music discrimination ability. Despite compliance from the CI-participants, we found no effect of the music training, likely resulting from the brevity of the program. This is the first study showing significant brain responses to musical feature changes in prelingually deaf adolescent CI users and their associations with behavioral measures, implying neural predispositions for at least some aspects of music processing. Future studies should test any beneficial effects of a longer lasting music intervention in adolescent CI users.

  12. An online brain-computer interface based on shifting attention to concurrent streams of auditory stimuli

    Science.gov (United States)

    Hill, N. J.; Schölkopf, B.

    2012-04-01

    We report on the development and online testing of an electroencephalogram-based brain-computer interface (BCI) that aims to be usable by completely paralysed users—for whom visual or motor-system-based BCIs may not be suitable, and among whom reports of successful BCI use have so far been very rare. The current approach exploits covert shifts of attention to auditory stimuli in a dichotic-listening stimulus design. To compare the efficacy of event-related potentials (ERPs) and steady-state auditory evoked potentials (SSAEPs), the stimuli were designed such that they elicited both ERPs and SSAEPs simultaneously. Trial-by-trial feedback was provided online, based on subjects' modulation of N1 and P3 ERP components measured during single 5 s stimulation intervals. All 13 healthy subjects were able to use the BCI, with performance in a binary left/right choice task ranging from 75% to 96% correct across subjects (mean 85%). BCI classification was based on the contrast between stimuli in the attended stream and stimuli in the unattended stream, making use of every stimulus, rather than contrasting frequent standard and rare ‘oddball’ stimuli. SSAEPs were assessed offline: for all subjects, spectral components at the two exactly known modulation frequencies allowed discrimination of pre-stimulus from stimulus intervals, and of left-only stimuli from right-only stimuli when one side of the dichotic stimulus pair was muted. However, attention modulation of SSAEPs was not sufficient for single-trial BCI communication, even when the subject's attention was clearly focused well enough to allow classification of the same trials via ERPs. ERPs clearly provided a superior basis for BCI. The ERP results are a promising step towards the development of a simple-to-use, reliable yes/no communication system for users in the most severely paralysed states, as well as potential attention-monitoring and -training applications outside the context of assistive technology.

  13. BDNF Increases Survival and Neuronal Differentiation of Human Neural Precursor Cells Cotransplanted with a Nanofiber Gel to the Auditory Nerve in a Rat Model of Neuronal Damage

    Directory of Open Access Journals (Sweden)

    Yu Jiao

    2014-01-01

    Full Text Available Objectives. To study possible nerve regeneration of a damaged auditory nerve by the use of stem cell transplantation. Methods. We transplanted HNPCs to the rat AN trunk by the internal auditory meatus (IAM. Furthermore, we studied if addition of BDNF affects survival and phenotypic differentiation of the grafted HNPCs. A bioactive nanofiber gel (PA gel, in selected groups mixed with BDNF, was applied close to the implanted cells. Before transplantation, all rats had been deafened by a round window niche application of β-bungarotoxin. This neurotoxin causes a selective toxic destruction of the AN while keeping the hair cells intact. Results. Overall, HNPCs survived well for up to six weeks in all groups. However, transplants receiving the BDNF-containing PA gel demonstrated significantly higher numbers of HNPCs and neuronal differentiation. At six weeks, a majority of the HNPCs had migrated into the brain stem and differentiated. Differentiated human cells as well as neurites were observed in the vicinity of the cochlear nucleus. Conclusion. Our results indicate that human neural precursor cells (HNPC integration with host tissue benefits from additional brain derived neurotrophic factor (BDNF treatment and that these cells appear to be good candidates for further regenerative studies on the auditory nerve (AN.

  14. Prediction of Speech Recognition in Cochlear Implant Users by Adapting Auditory Models to Psychophysical Data

    Directory of Open Access Journals (Sweden)

    Svante Stadler

    2009-01-01

    Full Text Available Users of cochlear implants (CIs vary widely in their ability to recognize speech in noisy conditions. There are many factors that may influence their performance. We have investigated to what degree it can be explained by the users' ability to discriminate spectral shapes. A speech recognition task has been simulated using both a simple and a complex models of CI hearing. The models were individualized by adapting their parameters to fit the results of a spectral discrimination test. The predicted speech recognition performance was compared to experimental results, and they were significantly correlated. The presented framework may be used to simulate the effects of changing the CI encoding strategy.

  15. Application of modified auditory profile in observation of hearing rehabilitation effects among adult partially deaf patients with cochlear implant system

    Directory of Open Access Journals (Sweden)

    Pankovska A.

    2013-12-01

    Full Text Available Aim: to obtain results in order to organize an individual profile of patient's hearing skills, which is a graphic illustration of obtained results that are used to monitor and provide appropriate assessment of the rehabilitation process using the modified set of hearing abilities tests. Material and methods. Material includes 24 adult patients (19 female and 5 male with partial deafness. All of them use cochlear implants. 6 patients have been using the Cl for no more than 6 months. 12 subjects have been using the Cl for more than 6 months, 3 of them have been using the Cl for more than a year and 3 people have been using the Cl for more than 24 months. Results. Research was based on 18 tasks. In the 8 of them 24 patients obtained the result of 100% identification just one month after the first speech processor fitting. However significant changes were observed in the remaining 10 tasks. 3 complete profiles of the patients hearing skills were created. Conclusions. Results obtained by the patients confirm that the set of supervision materials designed to control the effects of rehabilitation and proposed as pilot study is valuable and can be used in diagnostics. Formula developed on the basis of auditory skill profile of the patient provides clear information on patient's progress (both to a patient and a therapist. It helps determine exercises for the next stages of rehabilitation.

  16. Mesenchymal Stem Cells in the Treatment of Traumatic Brain Injury

    Science.gov (United States)

    Hasan, Anwarul; Deeb, George; Rahal, Rahaf; Atwi, Khairallah; Mondello, Stefania; Marei, Hany Elsayed; Gali, Amr; Sleiman, Eliana

    2017-01-01

    Traumatic brain injury (TBI) is characterized by a disruption in the normal function of the brain due to an injury following a trauma, which can potentially cause severe physical, cognitive, and emotional impairment. The primary insult to the brain initiates secondary injury cascades consisting of multiple complex biochemical responses of the brain that significantly influence the overall severity of the brain damage and clinical sequelae. The use of mesenchymal stem cells (MSCs) offers huge potential for application in the treatment of TBI. MSCs have immunosuppressive properties that reduce inflammation in injured tissue. As such, they could be used to modulate the secondary mechanisms of injury and halt the progression of the secondary insult in the brain after injury. Particularly, MSCs are capable of secreting growth factors that facilitate the regrowth of neurons in the brain. The relative abundance of harvest sources of MSCs also makes them particularly appealing. Recently, numerous studies have investigated the effects of infusion of MSCs into animal models of TBI. The results have shown significant improvement in the motor function of the damaged brain tissues. In this review, we summarize the recent advances in the application of MSCs in the treatment of TBI. The review starts with a brief introduction of the pathophysiology of TBI, followed by the biology of MSCs, and the application of MSCs in TBI treatment. The challenges associated with the application of MSCs in the treatment of TBI and strategies to address those challenges in the future have also been discussed.

  17. Auditory Hallucinations in Acute Stroke

    Directory of Open Access Journals (Sweden)

    Yair Lampl

    2005-01-01

    Full Text Available Auditory hallucinations are uncommon phenomena which can be directly caused by acute stroke, mostly described after lesions of the brain stem, very rarely reported after cortical strokes. The purpose of this study is to determine the frequency of this phenomenon. In a cross sectional study, 641 stroke patients were followed in the period between 1996–2000. Each patient underwent comprehensive investigation and follow-up. Four patients were found to have post cortical stroke auditory hallucinations. All of them occurred after an ischemic lesion of the right temporal lobe. After no more than four months, all patients were symptom-free and without therapy. The fact the auditory hallucinations may be of cortical origin must be taken into consideration in the treatment of stroke patients. The phenomenon may be completely reversible after a couple of months.

  18. Changes in strain patterns after implantation of a short stem with metaphyseal anchorage compared to a standard stem: an experimental study in synthetic bone

    Directory of Open Access Journals (Sweden)

    Jens Gronewold

    2014-03-01

    Full Text Available Short stem hip arthroplasties with predominantly metaphyseal fixation, such as the METHA® stem (Aesculap, Tuttlingen, Germany, are recommended because they are presumed to allow a more physiologic load transfer and thus a reduction of stress-shielding. However, the hypothesized metaphyseal anchorage associated with the aforementioned benefits still needs to be verified. Therefore, the METHA short stem and the Bicontact® standard stem (Aesculap, Tuttlingen, Germany were tested biomechanically in synthetic femora while strain gauges monitored their corresponding strain patterns. For the METHA stem, the strains in all tested locations including the region of the calcar (87% of the non-implanted femur were similar to conditions of synthetic bone without implanted stem. The Bicontact stem showed approximately the level of strain of the non-implanted femur on the lateral and medial aspect in the proximal diaphysis of the femur. On the anterior and posterior aspect of the proximal metaphysis the strains reached averages of 78% and 87% of the non-implanted femur, respectively. This study revealed primary metaphyseal anchorage of the METHA short stem, as opposed to a metaphyseal-diaphyseal anchorage of the Bicontact stem.

  19. Behavioral and brain pattern differences between acting and observing in an auditory task

    Directory of Open Access Journals (Sweden)

    Ventouras Errikos M

    2009-01-01

    Full Text Available Abstract Background Recent research has shown that errors seem to influence the patterns of brain activity. Additionally current notions support the idea that similar brain mechanisms are activated during acting and observing. The aim of the present study was to examine the patterns of brain activity of actors and observers elicited upon receiving feedback information of the actor's response. Methods The task used in the present research was an auditory identification task that included both acting and observing settings, ensuring concurrent ERP measurements of both participants. The performance of the participants was investigated in conditions of varying complexity. ERP data were analyzed with regards to the conditions of acting and observing in conjunction to correct and erroneous responses. Results The obtained results showed that the complexity induced by cue dissimilarity between trials was a demodulating factor leading to poorer performance. The electrophysiological results suggest that feedback information results in different intensities of the ERP patterns of observers and actors depending on whether the actor had made an error or not. The LORETA source localization method yielded significantly larger electrical activity in the supplementary motor area (Brodmann area 6, the posterior cingulate gyrus (Brodmann area 31/23 and the parietal lobe (Precuneus/Brodmann area 7/5. Conclusion These findings suggest that feedback information has a different effect on the intensities of the ERP patterns of actors and observers depending on whether the actor committed an error. Certain neural systems, including medial frontal area, posterior cingulate gyrus and precuneus may mediate these modulating effects. Further research is needed to elucidate in more detail the neuroanatomical and neuropsychological substrates of these systems.

  20. Anaesthetic management of a patient with deep brain stimulation implant for radical nephrectomy

    Directory of Open Access Journals (Sweden)

    Monica Khetarpal

    2014-01-01

    Full Text Available A 63-year-old man with severe Parkinson′s disease (PD who had been implanted with deep brain stimulators into both sides underwent radical nephrectomy under general anaesthesia with standard monitoring. Deep brain stimulation (DBS is an alternative and effective treatment option for severe and refractory PD and other illnesses such as essential tremor and intractable epilepsy. Anaesthesia in the patients with implanted neurostimulator requires special consideration because of the interaction between neurostimulator and the diathermy. The diathermy can damage the brain tissue at the site of electrode. There are no standard guidelines for the anaesthetic management of a patient with DBS electrode in situ posted for surgery.

  1. Stem cell-paved biobridges facilitate stem transplant and host brain cell interactions for stroke therapy.

    Science.gov (United States)

    Duncan, Kelsey; Gonzales-Portillo, Gabriel S; Acosta, Sandra A; Kaneko, Yuji; Borlongan, Cesar V; Tajiri, Naoki

    2015-10-14

    Distinguished by an infarct core encased within a penumbra, stroke remains a primary source of mortality within the United States. While our scientific knowledge regarding the pathology of stroke continues to improve, clinical treatment options for patients suffering from stroke are extremely limited. Tissue plasminogen activator (tPA) remains the sole FDA-approved drug proven to be helpful following stroke. However, due to the need to administer the drug within 4.5h of stroke onset its usefulness is constrained to less than 5% of all patients suffering from ischemic stroke. One experimental therapy for the treatment of stroke involves the utilization of stem cells. Stem cell transplantation has been linked to therapeutic benefit by means of cell replacement and release of growth factors; however the precise means by which this is accomplished has not yet been clearly delineated. Using a traumatic brain injury model, we recently demonstrated the ability of transplanted mesenchymal stromal cells (MSCs) to form a biobridge connecting the area of injury to the neurogenic niche within the brain. We hypothesize that MSCs may also have the capacity to create a similar biobridge following stroke; thereby forming a conduit between the neurogenic niche and the stroke core and peri-infarct area. We propose that this biobridge could assist and promote interaction of host brain cells with transplanted stem cells and offer more opportunities to enhance the effectiveness of stem cell therapy in stroke. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.

  2. Communication and control by listening: towards optimal design of a two-class auditory streaming brain-computer interface

    Directory of Open Access Journals (Sweden)

    N. Jeremy Hill

    2012-12-01

    Full Text Available Most brain-computer interface (BCI systems require users to modulate brain signals in response to visual stimuli. Thus, they may not be useful to people with limited vision, such as those with severe paralysis. One important approach for overcoming this issue is auditory streaming, an approach whereby a BCI system is driven by shifts of attention between two dichotically presented auditory stimulus streams. Motivated by the long-term goal of translating such a system into a reliable, simple yes-no interface for clinical usage, we aim to answer two main questions. First, we asked which of two previously-published variants provides superior performance: a fixed-phase (FP design in which the streams have equal period and opposite phase, or a drifting-phase (DP design where the periods are unequal. We found FP to be superior to DP (p = 0.002: average performance levels were 80% and 72% correct, respectively. We were also able to show, in a pilot with one subject, that auditory streaming can support continuous control and neurofeedback applications: by shifting attention between ongoing left and right auditory streams, the subject was able to control the position of a paddle in a computer game. Second, we examined whether the system is dependent on eye movements, since it is known that eye movements and auditory attention may influence each other, and any dependence on the ability to move one’s eyes would be a barrier to translation to paralyzed users. We discovered that, despite instructions, some subjects did make eye movements that were indicative of the direction of attention. However, there was no correlation, across subjects, between the reliability of the eye movement signal and the reliability of the BCI system, indicating that our system was configured to work independently of eye movement. Together, these findings are an encouraging step forward toward BCIs that provide practical communication and control options for the most severely

  3. Effect of Hearing Aids on Auditory Function in Infants with Perinatal Brain Injury and Severe Hearing Loss

    Science.gov (United States)

    Moreno-Aguirre, Alma Janeth; Santiago-Rodríguez, Efraín; Harmony, Thalía; Fernández-Bouzas, Antonio

    2012-01-01

    Background Approximately 2–4% of newborns with perinatal risk factors present with hearing loss. Our aim was to analyze the effect of hearing aid use on auditory function evaluated based on otoacoustic emissions (OAEs), auditory brain responses (ABRs) and auditory steady state responses (ASSRs) in infants with perinatal brain injury and profound hearing loss. Methodology/Principal Findings A prospective, longitudinal study of auditory function in infants with profound hearing loss. Right side hearing before and after hearing aid use was compared with left side hearing (not stimulated and used as control). All infants were subjected to OAE, ABR and ASSR evaluations before and after hearing aid use. The average ABR threshold decreased from 90.0 to 80.0 dB (p = 0.003) after six months of hearing aid use. In the left ear, which was used as a control, the ABR threshold decreased from 94.6 to 87.6 dB, which was not significant (p>0.05). In addition, the ASSR threshold in the 4000-Hz frequency decreased from 89 dB to 72 dB (p = 0.013) after six months of right ear hearing aid use; the other frequencies in the right ear and all frequencies in the left ear did not show significant differences in any of the measured parameters (p>0.05). OAEs were absent in the baseline test and showed no changes after hearing aid use in the right ear (p>0.05). Conclusions/Significance This study provides evidence that early hearing aid use decreases the hearing threshold in ABR and ASSR assessments with no functional modifications in the auditory receptor, as evaluated by OAEs. PMID:22808289

  4. Mesenchymal stem cell interaction with ultra smooth nanostructured diamond for wear resistant orthopaedic implants

    OpenAIRE

    Clem, William C.; Chowdhury, Shafiul; Catledge, Shane A.; Weimer, Jeffrey J.; Shaikh, Faheem M; Hennessy, Kristin M; Konovalov, Valery V.; Hill, Michael R; Waterfeld, Alfred; Bellis, Susan L.; Vohra, Yogesh K.

    2008-01-01

    Ultra smooth nanostructured diamond (USND) can be applied to greatly increase the wear resistance of orthopaedic implants over conventional designs. Herein we describe surface modification techniques and cytocompatibility studies performed on this new material. We report that hydrogen (H) -terminated USND surfaces supported robust mesenchymal stem cell (MSC) adhesion and survival, while oxygen (O) and fluorine (F) -terminated surfaces resisted cell adhesion, indicating that USND can be modifi...

  5. Localization of brain activity during auditory verbal short-term memory derived from magnetic recordings.

    Science.gov (United States)

    Starr, A; Kristeva, R; Cheyne, D; Lindinger, G; Deecke, L

    1991-09-01

    We have studied magnetic and electrical fields of the brain in normal subjects during the performance of an auditory verbal short-term memory task. On each trial 3 digits, selected from the numbers 'one' through 'nine', were presented for memorization followed by a probe number which could or could not be a member of the preceding memory set. The subject pressed an appropriate response button and accuracy and reaction time were measured. Magnetic fields recorded from up to 63 sites over both hemispheres revealed a transient field at 110 ms to both the memory item and the probe consistent with a dipole source in Heschl's gyrus; a sustained magnetic field between 300 and 800 ms to just the memory items localized to the temporal lobe slightly deeper and posterior to Heschl's gyri; and a sustained magnetic field between 300 and 800 ms to just the probes localized bilaterally to the medio-basal temporal lobes. These results are related to clinical disorders of short-term memory in man.

  6. Noninvasive brain stimulation and auditory verbal hallucinations: new techniques and future directions

    Directory of Open Access Journals (Sweden)

    Peter eMoseley

    2016-01-01

    Full Text Available Auditory verbal hallucinations (AVHs are the experience of hearing a voice in the absence of any speaker. Results from recent attempts to treat AVHs with neurostimulation (rTMS or tDCS to the left temporoparietal junction have not been conclusive, but suggest that it may be a promising treatment option for some individuals. Some evidence suggests that the therapeutic effect of neurostimulation on AVHs may result from modulation of cortical areas involved in the ability to monitor the source of self-generated information. Here, we provide a brief overview of cognitive models and neurostimulation paradigms associated with treatment of AVHs, and discuss techniques that could be explored in the future to improve the efficacy of treatment, including alternating current and random noise stimulation. Technical issues surrounding the use of neurostimulation as a treatment option are discussed (including methods to localise the targeted cortical area, and the state-dependent effects of brain stimulation, as are issues surrounding the acceptability of neurostimulation for adolescent populations and individuals who experience qualitatively different types of AVH.

  7. Rescue of Brain Function Using Tunneling Nanotubes Between Neural Stem Cells and Brain Microvascular Endothelial Cells.

    Science.gov (United States)

    Wang, Xiaoqing; Yu, Xiaowen; Xie, Chong; Tan, Zijian; Tian, Qi; Zhu, Desheng; Liu, Mingyuan; Guan, Yangtai

    2016-05-01

    Evidence indicates that neural stem cells (NSCs) can ameliorate cerebral ischemia in animal models. In this study, we investigated the mechanism underlying one of the neuroprotective effects of NSCs: tunneling nanotube (TNT) formation. We addressed whether the control of cell-to-cell communication processes between NSCs and brain microvascular endothelial cells (BMECs) and, particularly, the control of TNT formation could influence the rescue function of stem cells. In an attempt to mimic the cellular microenvironment in vitro, a co-culture system consisting of terminally differentiated BMECs from mice in a distressed state and NSCs was constructed. Additionally, engraftment experiments with infarcted mouse brains revealed that control of TNT formation influenced the effects of stem cell transplantation in vivo. In conclusion, our findings provide the first evidence that TNTs exist between NSCs and BMECs and that regulation of TNT formation alters cell function.

  8. Rey's Auditory Verbal Learning Test scores can be predicted from whole brain MRI in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Elaheh Moradi

    2017-01-01

    Full Text Available Rey's Auditory Verbal Learning Test (RAVLT is a powerful neuropsychological tool for testing episodic memory, which is widely used for the cognitive assessment in dementia and pre-dementia conditions. Several studies have shown that an impairment in RAVLT scores reflect well the underlying pathology caused by Alzheimer's disease (AD, thus making RAVLT an effective early marker to detect AD in persons with memory complaints. We investigated the association between RAVLT scores (RAVLT Immediate and RAVLT Percent Forgetting and the structural brain atrophy caused by AD. The aim was to comprehensively study to what extent the RAVLT scores are predictable based on structural magnetic resonance imaging (MRI data using machine learning approaches as well as to find the most important brain regions for the estimation of RAVLT scores. For this, we built a predictive model to estimate RAVLT scores from gray matter density via elastic net penalized linear regression model. The proposed approach provided highly significant cross-validated correlation between the estimated and observed RAVLT Immediate (R = 0.50 and RAVLT Percent Forgetting (R = 0.43 in a dataset consisting of 806 AD, mild cognitive impairment (MCI or healthy subjects. In addition, the selected machine learning method provided more accurate estimates of RAVLT scores than the relevance vector regression used earlier for the estimation of RAVLT based on MRI data. The top predictors were medial temporal lobe structures and amygdala for the estimation of RAVLT Immediate and angular gyrus, hippocampus and amygdala for the estimation of RAVLT Percent Forgetting. Further, the conversion of MCI subjects to AD in 3-years could be predicted based on either observed or estimated RAVLT scores with an accuracy comparable to MRI-based biomarkers.

  9. Simultaneous implant placement and bone regeneration around dental implants using tissue-engineered bone with fibrin glue, mesenchymal stem cells and platelet-rich plasma.

    Science.gov (United States)

    Ito, Kenji; Yamada, Yoichi; Naiki, Takahito; Ueda, Minoru

    2006-10-01

    This study was undertaken to evaluate the use of tissue-engineered bone as grafting material for alveolar augmentation with simultaneous implant placement. Twelve adult hybrid dogs were used in this study. One month after the extraction of teeth in the mandible region, bone defects on both sides of the mandible were induced using a trephine bar with a diameter of 10 mm. Dog mesenchymal stem cells (dMSCs) were obtained via iliac bone biopsy and cultured for 4 weeks before implantation. After installing the dental implants, the defects were simultaneously implanted with the following graft materials: (i) fibrin, (ii) dMSCs and fibrin (dMSCs/fibrin), (iii) dMSCs, platelet-rich plasma (PRP) and fibrin (dMSCs/PRP/fibrin) and (iv) control (defect only). The implants were assessed by histological and histomorphometric analysis, 2, 4 and 8 weeks after implantation. The implants exhibited varying degrees of bone-implant contact (BIC). The BIC was 17%, 19% and 29% (control), 20%, 22% and 25% (fibrin), 22%, 32% and 42% (dMSCs/fibrin) and 25%, 49% and 53% (dMSCs/PRP/fibrin) after 2, 4 and 8 weeks, respectively. This study suggests that tissue-engineered bone may be of sufficient quality for predictable enhancement of bone regeneration around dental implants when used simultaneous by with implant placement.

  10. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation.

    Science.gov (United States)

    Wallentin, Mikkel; Skakkebæk, Anne; Bojesen, Anders; Fedder, Jens; Laurberg, Peter; Østergaard, John R; Hertz, Jens Michael; Pedersen, Anders Degn; Gravholt, Claus Højbjerg

    2016-01-01

    Klinefelter syndrome (47, XXY) (KS) is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS relative to a group of Controls to basic motor, perceptual, executive and adaptation tasks. Participants (N: KS = 49; Controls = 49) responded to whether the words "GREEN" or "RED" were displayed in green or red (incongruent versus congruent colors). One of the colors was presented three times as often as the other, making it possible to study both congruency and adaptation effects independently. Auditory stimuli saying "GREEN" or "RED" had the same distribution, making it possible to study effects of perceptual modality as well as Frequency effects across modalities. We found that KS had an increased response to motor output in primary motor cortex and an increased response to auditory stimuli in auditory cortices, but no difference in primary visual cortices. KS displayed a diminished response to written visual stimuli in secondary visual regions near the Visual Word Form Area, consistent with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop) or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups. No effects of testosterone level or brain volume were found. In sum, the present findings suggest that auditory and motor systems in KS are selectively affected, perhaps as a compensatory strategy, and that this is not a systemic effect as it is not seen in the visual system.

  11. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation

    Directory of Open Access Journals (Sweden)

    Mikkel Wallentin

    2016-01-01

    Full Text Available Klinefelter syndrome (47, XXY (KS is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS relative to a group of Controls to basic motor, perceptual, executive and adaptation tasks. Participants (N: KS = 49; Controls = 49 responded to whether the words “GREEN” or “RED” were displayed in green or red (incongruent versus congruent colors. One of the colors was presented three times as often as the other, making it possible to study both congruency and adaptation effects independently. Auditory stimuli saying “GREEN” or “RED” had the same distribution, making it possible to study effects of perceptual modality as well as Frequency effects across modalities. We found that KS had an increased response to motor output in primary motor cortex and an increased response to auditory stimuli in auditory cortices, but no difference in primary visual cortices. KS displayed a diminished response to written visual stimuli in secondary visual regions near the Visual Word Form Area, consistent with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups. No effects of testosterone level or brain volume were found. In sum, the present findings suggest that auditory and motor systems in KS are selectively affected, perhaps as a compensatory strategy, and that this is not a systemic effect as it is not seen in the visual system.

  12. Cortical Auditory Disorders: A Case of Non-Verbal Disturbances Assessed with Event-Related Brain Potentials

    Directory of Open Access Journals (Sweden)

    Sönke Johannes

    1998-01-01

    Full Text Available In the auditory modality, there has been a considerable debate about some aspects of cortical disorders, especially about auditory forms of agnosia. Agnosia refers to an impaired comprehension of sensory information in the absence of deficits in primary sensory processes. In the non-verbal domain, sound agnosia and amusia have been reported but are frequently accompanied by language deficits whereas pure deficits are rare. Absolute pitch and musicians’ musical abilities have been associated with left hemispheric functions. We report the case of a right handed sound engineer with the absolute pitch who developed sound agnosia and amusia in the absence of verbal deficits after a right perisylvian stroke. His disabilities were assessed with the Seashore Test of Musical Functions, the tests of Wertheim and Botez (Wertheim and Botez, Brain 84, 1961, 19–30 and by event-related potentials (ERP recorded in a modified 'oddball paradigm’. Auditory ERP revealed a dissociation between the amplitudes of the P3a and P3b subcomponents with the P3b being reduced in amplitude while the P3a was undisturbed. This is interpreted as reflecting disturbances in target detection processes as indexed by the P3b. The findings that contradict some aspects of current knowledge about left/right hemispheric specialization in musical processing are discussed and related to the literature concerning cortical auditory disorders.

  13. An Evaluation of Training with an Auditory P300 Brain-Computer Interface for the Japanese Hiragana Syllabary

    Science.gov (United States)

    Halder, Sebastian; Takano, Kouji; Ora, Hiroki; Onishi, Akinari; Utsumi, Kota; Kansaku, Kenji

    2016-01-01

    Gaze-independent brain-computer interfaces (BCIs) are a possible communication channel for persons with paralysis. We investigated if it is possible to use auditory stimuli to create a BCI for the Japanese Hiragana syllabary, which has 46 Hiragana characters. Additionally, we investigated if training has an effect on accuracy despite the high amount of different stimuli involved. Able-bodied participants (N = 6) were asked to select 25 syllables (out of fifty possible choices) using a two step procedure: First the consonant (ten choices) and then the vowel (five choices). This was repeated on 3 separate days. Additionally, a person with spinal cord injury (SCI) participated in the experiment. Four out of six healthy participants reached Hiragana syllable accuracies above 70% and the information transfer rate increased from 1.7 bits/min in the first session to 3.2 bits/min in the third session. The accuracy of the participant with SCI increased from 12% (0.2 bits/min) to 56% (2 bits/min) in session three. Reliable selections from a 10 × 5 matrix using auditory stimuli were possible and performance is increased by training. We were able to show that auditory P300 BCIs can be used for communication with up to fifty symbols. This enables the use of the technology of auditory P300 BCIs with a variety of applications.

  14. Brain Implant Lets 'Locked-In' ALS Patient Communicate

    Science.gov (United States)

    ... important step toward creating powerful, fully implanted neuro-prosthetic systems to help people with paralysis and locked- ... tasked with controlling the muscles of the right hand. The goal: to pick up still-functioning nerve ...

  15. Anesthetic management of deep brain stimulator implantation in Meige′s syndrome

    Directory of Open Access Journals (Sweden)

    Kalpesh V Bhoyar

    2012-01-01

    Full Text Available Meige′s syndrome is rare form of orofacial dystonia. There is unfortunately no cure, but occasionally patients may improve with time. We present the successful management of a palladial deep brain stimulator (DBS implantation for Meige′s syndrome. Dexmedetomidine infusion was used for sedation. The procedure lasted for around 12 h and the patient was comfortable, responsive, and cooperative over the extended period of time. The surgeons were comfortable with electrophysiologic brain mapping and clinical testing. DBS were implanted, through a burr hole, into the globus pallidus neurophysiological testing under guidance. The pulse generator battery was subcutaneously implanted into the chest wall under general anesthesia. The implanted pulse generator battery was started 2 days later and the patient showed dramatic improvement in his symptoms.

  16. Intra-articular Implantation of Mesenchymal Stem Cells, Part 2

    Science.gov (United States)

    Kraeutler, Matthew J.; Mitchell, Justin J.; Chahla, Jorge; McCarty, Eric C.; Pascual-Garrido, Cecilia

    2017-01-01

    Knee osteoarthritis (OA) after partial or total meniscectomy is a prevalent issue that patients must face. Various methods of replacing meniscal tissue have been studied to avoid this progression, including meniscal allograft transplantation, meniscal scaffolds, and synthetic meniscus replacement. Studies have shown that meniscal scaffolds may improve symptoms but have not been shown to prevent progression of OA. Recently, mesenchymal stem cells (MSCs) have been proposed as a possible biological therapy for meniscal regeneration. Several animal studies and 1 human study have evaluated the effect of transplanting MSCs into the knee joint after partial meniscectomy. The purpose of this review was to assess the outcomes of intra-articular transplantation of MSCs on meniscal regeneration in animals and humans after partial meniscectomy. Limited results from animal studies suggest that there is some potential for intra-articular injection of MSCs for the regeneration of meniscal tissue. However, further studies are necessary to determine the quality of regenerated meniscal tissue through histological and biomechanical testing. PMID:28203596

  17. Theranostic 3-Dimensional nano brain-implant for prolonged and localized treatment of recurrent glioma

    Science.gov (United States)

    Ramachandran, Ranjith; Junnuthula, Vijayabhaskar Reddy; Gowd, G. Siddaramana; Ashokan, Anusha; Thomas, John; Peethambaran, Reshmi; Thomas, Anoop; Unni, Ayalur Kodakara Kochugovindan; Panikar, Dilip; Nair, Shantikumar V.; Koyakutty, Manzoor

    2017-03-01

    Localized and controlled delivery of chemotherapeutics directly in brain-tumor for prolonged periods may radically improve the prognosis of recurrent glioblastoma. Here, we report a unique method of nanofiber by fiber controlled delivery of anti-cancer drug, Temozolomide, in orthotopic brain-tumor for one month using flexible polymeric nano-implant. A library of drug loaded (20 wt%) electrospun nanofiber of PLGA-PLA-PCL blends with distinct in vivo brain-release kinetics (hours to months) were numerically selected and a single nano-implant was formed by co-electrospinning of nano-fiber such that different set of fibres releases the drug for a specific periods from days to months by fiber-by-fiber switching. Orthotopic rat glioma implanted wafers showed constant drug release (116.6 μg/day) with negligible leakage into the peripheral blood (tumor versus peripheral blood. Most importantly, implant with one month release profile resulted in long-term (>4 month) survival of 85.7% animals whereas 07 day releasing implant showed tumor recurrence in 54.6% animals, rendering a median survival of only 74 days. In effect, we show that highly controlled drug delivery is possible for prolonged periods in orthotopic brain-tumor using combinatorial nanofibre libraries of bulk-eroding polymers, thereby controlling glioma recurrence.

  18. Establishment of 9L/F344 rat intracerebral glioma model of brain tumor stem cells

    Directory of Open Access Journals (Sweden)

    Zong-yu XIAO

    2015-04-01

    Full Text Available Objective To establish the 9L/F344 rat intracerebral glioma model of brain tumor stem cells.  Methods Rat 9L gliosarcoma stem-like cells were cultured in serum-free suspension. The expression of CD133 and nestin were tested by immunohistochemistry. A total of 48 inbredline male F344 rats were randomly divided into 2 groups, and 9L tumor sphere cells and 9L monolayer cells were respectively implanted into the right caudate nucleus of F344 rats in 2 groups. Survival time was observed and determined using the method of Kaplan-Meier survival analysis. Fourteen days after implantation or when the rats were dying, their brains were perfused and sectioned for HE staining, and CD133 and nestin were detected by immunohistochemistry.  Results Rat 9L tumor spheres were formed with suspension culture in serum-free medium. The gliomas formed in both groups were invasive without obvious capsule. More new vessels, bleeding and necrosis could be detected in 9L tumor spheres group. The tumor cells in both groups were positive for CD133 and nestin. There was no significant difference in the expression of CD133 and nestin between 2 groups (P > 0.05, for all. According to the expression of nestin, the tumors formed by 9L tumor sphere cells were more invasive. The median survival time of the rats bearing 9L tumor sphere cells was 15 d (95%CI: 15.219-15.781, and the median survival time of the rats bearing 9L monolayer cells was 21 d (95%CI: 20.395-21.605. There was significant difference between 2 groups (χ2 = 12.800, P = 0.000.  Conclusions 9L/F344 rat intracerebral glioma model of brain tumor stem cells is successfully established, which provides a glioma model for the future research. DOI: 10.3969/j.issn.1672-6731.2015.04.012

  19. Atypical Bilateral Brain Synchronization in the Early Stage of Human Voice Auditory Processing in Young Children with Autism

    Science.gov (United States)

    Kurita, Toshiharu; Kikuchi, Mitsuru; Yoshimura, Yuko; Hiraishi, Hirotoshi; Hasegawa, Chiaki; Takahashi, Tetsuya; Hirosawa, Tetsu; Furutani, Naoki; Higashida, Haruhiro; Ikeda, Takashi; Mutou, Kouhei; Asada, Minoru; Minabe, Yoshio

    2016-01-01

    Autism spectrum disorder (ASD) has been postulated to involve impaired neuronal cooperation in large-scale neural networks, including cortico-cortical interhemispheric circuitry. In the context of ASD, alterations in both peripheral and central auditory processes have also attracted a great deal of interest because these changes appear to represent pathophysiological processes; therefore, many prior studies have focused on atypical auditory responses in ASD. The auditory evoked field (AEF), recorded by magnetoencephalography, and the synchronization of these processes between right and left hemispheres was recently suggested to reflect various cognitive abilities in children. However, to date, no previous study has focused on AEF synchronization in ASD subjects. To assess global coordination across spatially distributed brain regions, the analysis of Omega complexity from multichannel neurophysiological data was proposed. Using Omega complexity analysis, we investigated the global coordination of AEFs in 3–8-year-old typically developing (TD) children (n = 50) and children with ASD (n = 50) in 50-ms time-windows. Children with ASD displayed significantly higher Omega complexities compared with TD children in the time-window of 0–50 ms, suggesting lower whole brain synchronization in the early stage of the P1m component. When we analyzed the left and right hemispheres separately, no significant differences in any time-windows were observed. These results suggest lower right-left hemispheric synchronization in children with ASD compared with TD children. Our study provides new evidence of aberrant neural synchronization in young children with ASD by investigating auditory evoked neural responses to the human voice. PMID:27074011

  20. Mg ion implantation on SLA-treated titanium surface and its effects on the behavior of mesenchymal stem cell

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Beom-Su; Kim, Jin Seong [Wonkwang Bone Regeneration Research Institute, Wonkwang University, Iksan 570-749 (Korea, Republic of); Bonecell Biotech Inc., 77, Dunsan-ro, Seo-gu, Daejeon 302-830 (Korea, Republic of); Park, Young Min [DIO Corporation, 66, Centum seo-ro, Haeundae-gu, Busan (Korea, Republic of); Choi, Bo-Young [Department of Oral and maxillofacial Surgery, Wonkwang University Daejeon Dental Hospital, Daejeon 302-830 (Korea, Republic of); Lee, Jun, E-mail: omslee@wku.ac.kr [Wonkwang Bone Regeneration Research Institute, Wonkwang University, Iksan 570-749 (Korea, Republic of); Bonecell Biotech Inc., 77, Dunsan-ro, Seo-gu, Daejeon 302-830 (Korea, Republic of)

    2013-04-01

    Magnesium (Mg) is one of the most important ions associated with bone osseointegration. The aim of this study was to evaluate the cellular effects of Mg implantation in titanium (Ti) surfaces treated with sand blast using large grit and acid etching (SLA). Mg ions were implanted into the surface via vacuum arc source ion implantation. The surface morphology, chemical properties, and the amount of Mg ion release were evaluated by scanning electron microscopy (SEM), Auger electron spectroscopy (AES), Rutherford backscattering spectroscopy (RBS), and inductively coupled plasma-optical emission spectrometer (ICP-OES). Human mesenchymal stem cells (hMSCs) were used to evaluate cellular parameters such as proliferation, cytotoxicity, and adhesion morphology by MTS assay, live/dead assay, and SEM. Furthermore, osteoblast differentiation was determined on the basis of alkaline phosphatase (ALP) activity and the degree of calcium accumulation. In the Mg ion-implanted disk, 2.3 × 10{sup 16} ions/cm{sup 2} was retained. However, after Mg ion implantation, the surface morphology did not change. Implanted Mg ions were rapidly released during the first 7 days in vitro. The MTS assay, live/dead assay, and SEM demonstrated increased cell attachment and growth on the Mg ion-implanted surface. In particular, Mg ion implantation increased the initial cell adhesion, and in an osteoblast differentiation assay, ALP activity and calcium accumulation. These findings suggest that Mg ion implantation using the plasma source ion implantation (PSII) technique may be useful for SLA-treated Ti dental implants to improve their osseointegration capacity. - Highlights: ► Mg ion was coated onto surface of SLA treated titanium via vacuum arc source ion implantation method. ► The morphological characteristics did not change after Mg ion implantation. ► Mg ion implanted SLA Ti is highly cytocompatible. ► Initial cell adhesion of MSCs is improved by Mg ion implantation. ► Mg ion implantation

  1. Auditory hallucinations.

    Science.gov (United States)

    Blom, Jan Dirk

    2015-01-01

    Auditory hallucinations constitute a phenomenologically rich group of endogenously mediated percepts which are associated with psychiatric, neurologic, otologic, and other medical conditions, but which are also experienced by 10-15% of all healthy individuals in the general population. The group of phenomena is probably best known for its verbal auditory subtype, but it also includes musical hallucinations, echo of reading, exploding-head syndrome, and many other types. The subgroup of verbal auditory hallucinations has been studied extensively with the aid of neuroimaging techniques, and from those studies emerges an outline of a functional as well as a structural network of widely distributed brain areas involved in their mediation. The present chapter provides an overview of the various types of auditory hallucination described in the literature, summarizes our current knowledge of the auditory networks involved in their mediation, and draws on ideas from the philosophy of science and network science to reconceptualize the auditory hallucinatory experience, and point out directions for future research into its neurobiologic substrates. In addition, it provides an overview of known associations with various clinical conditions and of the existing evidence for pharmacologic and non-pharmacologic treatments.

  2. Deafness: Cross-modal plasticity and cochlear implants

    Science.gov (United States)

    Lee, Dong Soo; Lee, Jae Sung; Oh, Seung Ha; Kim, Seok-Ki; Kim, Jeung-Whoon; Chung, June-Key; Lee, Myung Chul; Kim, Chong Sun

    2001-01-01

    Hearing in profoundly deaf people can be helped by inserting an implant into the inner ear to stimulate the cochlear nerve. This also boosts the low metabolic activity of the auditory cortex, the region of the brain normally used for hearing. Other sensory modalities, such as sign language, can also activate the auditory cortex, a phenomenon known as cross-modal plasticity. Here we show that when metabolism in the auditory cortex of prelingually deaf children (whose hearing was lost before they learned to talk) has been restored by cross-modal plasticity, the auditory cortex can no longer respond to signals from a cochlear implant installed afterwards. Neural substrates in the auditory cortex might therefore be routed permanently to other cognitive processes in prelingually deaf patients.

  3. Brain Bases for Auditory Stimulus-Driven Figure-Ground Segregation

    OpenAIRE

    Teki, S.; Chait, M.; Kumar, S.; von Kriegstein, K.; Griffiths, T.D.

    2011-01-01

    Auditory figure-ground segregation, listeners' ability to selectively hear out a sound of interest from a background of competing sounds, is a fundamental aspect of scene analysis. In contrast to the disordered acoustic environment we experience during everyday listening, most studies of auditory segregation have used relatively simple, temporally regular signals. We developed a new figure-ground stimulus that incorporates stochastic variation of the figure and background that captures the ri...

  4. Brain Bases for Auditory Stimulus-Driven Figure–Ground Segregation

    OpenAIRE

    Teki, Sundeep; Chait, Maria; Kumar, Sukhbinder; von Kriegstein, Katharina; Timothy D Griffiths

    2011-01-01

    Auditory figure–ground segregation, listeners’ ability to selectively hear out a sound of interest from a background of competing sounds, is a fundamental aspect of scene analysis. In contrast to the disordered acoustic environment we experience during everyday listening, most studies of auditory segregation have used relatively simple, temporally regular signals. We developed a new figure–ground stimulus that incorporates stochastic variation of the figure and background that captures the ri...

  5. Cytokine Immunopathogenesis of Enterovirus 71 Brain Stem Encephalitis

    Directory of Open Access Journals (Sweden)

    Shih-Min Wang

    2012-01-01

    Full Text Available Enterovirus 71 (EV71 is one of the most important causes of herpangina and hand, foot, and mouth disease. It can also cause severe complications of the central nervous system (CNS. Brain stem encephalitis with pulmonary edema is the severe complication that can lead to death. EV71 replicates in leukocytes, endothelial cells, and dendritic cells resulting in the production of immune and inflammatory mediators that shape innate and acquired immune responses and the complications of disease. Cytokines, as a part of innate immunity, favor the development of antiviral and Th1 immune responses. Cytokines and chemokines play an important role in the pathogenesis EV71 brain stem encephalitis. Both the CNS and the systemic inflammatory responses to infection play important, but distinctly different, roles in the pathogenesis of EV71 pulmonary edema. Administration of intravenous immunoglobulin and milrinone, a phosphodiesterase inhibitor, has been shown to modulate inflammation, to reduce sympathetic overactivity, and to improve survival in patients with EV71 autonomic nervous system dysregulation and pulmonary edema.

  6. Correlation between heat shock protein 70 expression in the brain stem and sudden death after experimental traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    ZHAO Lian-xu; XU Xiao-hu; LIU Chao; PAN Su-yue; ZHU Jia-zhen; ZHANG Cheng

    2001-01-01

    Objective: The aim of this study was to determine the patterns of heat-shock protein 70 (HSP70) biosynthesis following traumatic brain injury, and observe the effect of HSP70 induction on the function of the vital center in the brain stem. Methods: Rat models of sudden death resulted form traumatic brain injury were produced, and HSP70 expression in the rat brain stem was determined by immunohistochemistry, the induction of HSP70 mRNA detected by RT-PCR. Results: The level of HSP70 mRNA was prominently elevated in the brain stem as early as 1 5 min following the impact injury, while HSP70 expression was only observed 3 to 6 h after the injury. It was also observed that the levels of HSP70 mRNA but not the protein were elevated in the brain stem of sudden death rats. Conclusion: The synthesis of HSP70 was significantly enhanced in the brain stem following traumatic injury, and the expression of HSP70 is beneficial to eliminate the stress agents, and to sustain the cellular protein homeostasis. When the injury disturbs the synthesis of HSP70 to disarm the protective mechanism of heat-shock proteins, dysfunction of the vital center in the brain stem, and consequently death may occur. Breach in the synchronization of HSP70 mRNA-protein can be indicative of fatal damage to the nerve cells.

  7. Implantable Microsystems for Anatomical Rewiring of Cortical Circuitry: A New Approach for Brain Repair

    Science.gov (United States)

    2009-03-01

    reaching, retrieval of small food items, and locomotion demonstrate that deficits persist during the 5-week recovery period following injury. This will...Implantable microsystem; Neuroplasticity ; Rehabilitation; Traumatic brain injury 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER...we have successfully induced TBI in the CFA, sparing the RFA. Behavioral assessments of reaching, retrieval of small food items, and locomotion

  8. Brain Implants for Prediction and Mitigation of Epileptic Seizures - Final CRADA Report

    Energy Technology Data Exchange (ETDEWEB)

    Gopalsami, Nachappa

    2016-09-29

    This is a CRADA final report on C0100901 between Argonne National Laboratory and Flint Hills Scientific, LLC of Lawrence, Kansas. Two brain implantable probes, a surface acoustic wave probe and a miniature cooling probe, were designed, built, and tested with excellent results.

  9. A case of a brain stem abscess with a favorable outcome

    NARCIS (Netherlands)

    Bulthuis, Vincent J; Gubler, Felix S; Teernstra, Onno P M; Temel, Yasin

    2015-01-01

    BACKGROUND: A brain stem abscess is a rare and severe medical condition. Here, we present a rare case of a brain stem abscess in a young pregnant woman, requiring acute stereotactic intervention. CASE DESCRIPTION: A 36-year-old woman presented with a headache, nausea, and vomiting, and computed tomo

  10. Electrical brain imaging evidences left auditory cortex involvement in speech and non-speech discrimination based on temporal features

    Directory of Open Access Journals (Sweden)

    Jancke Lutz

    2007-12-01

    Full Text Available Abstract Background Speech perception is based on a variety of spectral and temporal acoustic features available in the acoustic signal. Voice-onset time (VOT is considered an important cue that is cardinal for phonetic perception. Methods In the present study, we recorded and compared scalp auditory evoked potentials (AEP in response to consonant-vowel-syllables (CV with varying voice-onset-times (VOT and non-speech analogues with varying noise-onset-time (NOT. In particular, we aimed to investigate the spatio-temporal pattern of acoustic feature processing underlying elemental speech perception and relate this temporal processing mechanism to specific activations of the auditory cortex. Results Results show that the characteristic AEP waveform in response to consonant-vowel-syllables is on a par with those of non-speech sounds with analogue temporal characteristics. The amplitude of the N1a and N1b component of the auditory evoked potentials significantly correlated with the duration of the VOT in CV and likewise, with the duration of the NOT in non-speech sounds. Furthermore, current density maps indicate overlapping supratemporal networks involved in the perception of both speech and non-speech sounds with a bilateral activation pattern during the N1a time window and leftward asymmetry during the N1b time window. Elaborate regional statistical analysis of the activation over the middle and posterior portion of the supratemporal plane (STP revealed strong left lateralized responses over the middle STP for both the N1a and N1b component, and a functional leftward asymmetry over the posterior STP for the N1b component. Conclusion The present data demonstrate overlapping spatio-temporal brain responses during the perception of temporal acoustic cues in both speech and non-speech sounds. Source estimation evidences a preponderant role of the left middle and posterior auditory cortex in speech and non-speech discrimination based on temporal

  11. Transplantation of autologous bone marrow-derived mesenchymal stem cells for traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Jindou Jiang; Xingyao Bu; Meng Liu; Peixun Cheng

    2012-01-01

    Results from the present study demonstrated that transplantation of autologous bone marrow-derived mesenchymal stem cells into the lesion site in rat brain significantly ameliorated brain tissue pathological changes and brain edema, attenuated glial cell proliferation, and increased brain-derived neurotrophic factor expression. In addition, the number of cells double-labeled for 5-bromodeoxyuridine/glial fibrillary acidic protein and cells expressing nestin increased. Finally, blood vessels were newly generated, and the rats exhibited improved motor and cognitive functions. These results suggested that transplantation of autologous bone marrow-derived mesenchymal stem cells promoted brain remodeling and improved neurological functions following traumatic brain injury.

  12. Music and natural sounds in an auditory steady-state response based brain-computer interface to increase user acceptance.

    Science.gov (United States)

    Heo, Jeong; Baek, Hyun Jae; Hong, Seunghyeok; Chang, Min Hye; Lee, Jeong Su; Park, Kwang Suk

    2017-03-18

    Patients with total locked-in syndrome are conscious; however, they cannot express themselves because most of their voluntary muscles are paralyzed, and many of these patients have lost their eyesight. To improve the quality of life of these patients, there is an increasing need for communication-supporting technologies that leverage the remaining senses of the patient along with physiological signals. The auditory steady-state response (ASSR) is an electro-physiologic response to auditory stimulation that is amplitude-modulated by a specific frequency. By leveraging the phenomenon whereby ASSR is modulated by mind concentration, a brain-computer interface paradigm was proposed to classify the selective attention of the patient. In this paper, we propose an auditory stimulation method to minimize auditory stress by replacing the monotone carrier with familiar music and natural sounds for an ergonomic system. Piano and violin instrumentals were employed in the music sessions; the sounds of water streaming and cicadas singing were used in the natural sound sessions. Six healthy subjects participated in the experiment. Electroencephalograms were recorded using four electrodes (Cz, Oz, T7 and T8). Seven sessions were performed using different stimuli. The spectral power at 38 and 42Hz and their ratio for each electrode were extracted as features. Linear discriminant analysis was utilized to classify the selections for each subject. In offline analysis, the average classification accuracies with a modulation index of 1.0 were 89.67% and 87.67% using music and natural sounds, respectively. In online experiments, the average classification accuracies were 88.3% and 80.0% using music and natural sounds, respectively. Using the proposed method, we obtained significantly higher user-acceptance scores, while maintaining a high average classification accuracy.

  13. Towards user-friendly spelling with an auditory brain-computer interface: the CharStreamer paradigm.

    Directory of Open Access Journals (Sweden)

    Johannes Höhne

    Full Text Available Realizing the decoding of brain signals into control commands, brain-computer interfaces (BCI aim to establish an alternative communication pathway for locked-in patients. In contrast to most visual BCI approaches which use event-related potentials (ERP of the electroencephalogram, auditory BCI systems are challenged with ERP responses, which are less class-discriminant between attended and unattended stimuli. Furthermore, these auditory approaches have more complex interfaces which imposes a substantial workload on their users. Aiming for a maximally user-friendly spelling interface, this study introduces a novel auditory paradigm: "CharStreamer". The speller can be used with an instruction as simple as "please attend to what you want to spell". The stimuli of CharStreamer comprise 30 spoken sounds of letters and actions. As each of them is represented by the sound of itself and not by an artificial substitute, it can be selected in a one-step procedure. The mental mapping effort (sound stimuli to actions is thus minimized. Usability is further accounted for by an alphabetical stimulus presentation: contrary to random presentation orders, the user can foresee the presentation time of the target letter sound. Healthy, normal hearing users (n = 10 of the CharStreamer paradigm displayed ERP responses that systematically differed between target and non-target sounds. Class-discriminant features, however, varied individually from the typical N1-P2 complex and P3 ERP components found in control conditions with random sequences. To fully exploit the sequential presentation structure of CharStreamer, novel data analysis approaches and classification methods were introduced. The results of online spelling tests showed that a competitive spelling speed can be achieved with CharStreamer. With respect to user rating, it clearly outperforms a control setup with random presentation sequences.

  14. UV-activated 7-dehydrocholesterol-coated titanium implants promote differentiation of human umbilical cord mesenchymal stem cells into osteoblasts.

    Science.gov (United States)

    Satué, María; Ramis, Joana M; Monjo, Marta

    2016-01-01

    Vitamin D metabolites are essential for bone regeneration and mineral homeostasis. The vitamin D precursor 7-dehydrocholesterol can be used after UV irradiation to locally produce active vitamin D by osteoblastic cells. Furthermore, UV-irradiated 7-dehydrocholesterol is a biocompatible coating for titanium implants with positive effects on osteoblast differentiation. In this study, we examined the impact of titanium implants surfaces coated with UV-irradiated 7-dehydrocholesterol on the osteogenic differentiation of human umbilical cord mesenchymal stem cells. First, the synthesis of cholecalciferol (D3) was achieved through the incubation of the UV-activated 7-dehydrocholesterol coating for 48 h at 23℃. Further, we investigated in vitro the biocompatibility of this coating in human umbilical cord mesenchymal stem cells and its potential to enhance their differentiation towards the osteogenic lineage. Human umbilical cord mesenchymal stem cells cultured onto UV-irradiated 7-dehydrocholesterol-coated titanium implants surfaces, combined with osteogenic supplements, upregulated the gene expression of several osteogenic markers and showed higher alkaline phosphatase activity and calcein blue staining, suggesting increased mineralization. Thus, our results show that the use of UV irradiation on 7-dehydrocholesterol -treated titanium implants surfaces generates a bioactive coating that promotes the osteogenic differentiation of human umbilical cord mesenchymal stem cells, with regenerative potential for improving osseointegration in titanium-based bone anchored implants.

  15. Chronic tissue response to untethered microelectrode implants in the rat brain and spinal cord

    Science.gov (United States)

    Ersen, Ali; Elkabes, Stella; Freedman, David S.; Sahin, Mesut

    2015-02-01

    Objective. Microelectrodes implanted in the central nervous system (CNS) often fail in long term implants due to the immunological tissue response caused by tethering forces of the connecting wires. In addition to the tethering effect, there is a mechanical stress that occurs at the device-tissue interface simply because the microelectrode is a rigid body floating in soft tissue and it cannot reshape itself to comply with changes in the surrounding tissue. In the current study we evaluated the scar tissue formation to tetherless devices with two significantly different geometries in the rat brain and spinal cord in order to investigate the effects of device geometry. Approach. One of the implant geometries resembled the wireless, floating microstimulators that we are currently developing in our laboratory and the other was a (shank only) Michigan probe for comparison. Both electrodes were implanted into either the cervical spinal cord or the motor cortices, one on each side. Main results. The most pronounced astroglial and microglial reactions occurred within 20 μm from the device and decreased sharply at larger distances. Both cell types displayed the morphology of non-activated cells past the 100 μm perimeter. Even though the aspect ratios of the implants were different, the astroglial and microglial responses to both microelectrode types were very mild in the brain, stronger and yet limited in the spinal cord. Significance. These observations confirm previous reports and further suggest that tethering may be responsible for most of the tissue response in chronic implants and that the electrode size has a smaller contribution with floating electrodes. The electrode size may be playing primarily an amplifying role to the tethering forces in the brain whereas the size itself may induce chronic response in the spinal cord where the movement of surrounding tissues is more significant.

  16. Neural activity control of neural stem cells and SVZ niche response to brain injury

    OpenAIRE

    Páez González, Patricia

    2014-01-01

    Patricia Paez-Gonzalez Kuo Lab, Dept. of Cell Biology, Duke University Medical Center, NC,USA. Date: 11/16/2014 Utilizing stem cells in the adult brain hold great promise for regenerative medicine. Harnessing ability of adult neural stem cells (NSCs) to generate new neurons or other types of brain cells may provide much needed therapies for patients suffering from brain injuries or neuro-degenerative diseases such as Parkinson’s, Scizophrenia, or Alzheimer’s disease. However...

  17. Prospects and Limitations of Using Endogenous Neural Stem Cells for Brain Regeneration

    OpenAIRE

    Kazunobu Sawamoto; Eisuke Kako; Naoko Kaneko

    2011-01-01

    Neural stem cells (NSCs) are capable of producing a variety of neural cell types, and are indispensable for the development of the mammalian brain. NSCs can be induced in vitro from pluripotent stem cells, including embryonic stem cells and induced-pluripotent stem cells. Although the transplantation of these exogenous NSCs is a potential strategy for improving presently untreatable neurological conditions, there are several obstacles to its implementation, including tumorigenic, immunologica...

  18. Objective evaluation of fourth ventricle displacement in brain CT findings. 4 cases of brain stem tumor

    Energy Technology Data Exchange (ETDEWEB)

    Okino, Fumiko; Eguchi, Tsuyako; Shinohara, Teruo; Hatano, Mitsunori (Yamaguchi Univ., Ube (Japan). School of Medicine)

    1983-11-01

    Distance between the ridge of the sella turcica and the anterior wall of the fourth ventricle (a) and the distance between the ridge of the sella and the posterior pole in the occipital region (b) were measured on the slice visualizing the fourth ventricle and sella. The location of the fourth ventricle was expressed by a/b, and its normal value was calculated for comparison with that in a patient group. The a/b values of the control group were in the range of 0.33 and 0.48 with a mean +- SD of 0.41+-0.3 and was not subject to the influences of age, sex distinction, cranial shape or slicing direction. The a/b values of the patient group were all abnormal (more than mean +- 2SD of the control group) on initial CT and showed an increase with progress of the disease activity. Measurement of the a/b on brain CT was thought to serve as a useful indicator for early detection and follow-up of the course of lesions occupying the brain stem (especially brain stem tumors).

  19. Bird brains and songs : Neural mechanisms of auditory memory and perception in zebra finches

    NARCIS (Netherlands)

    Gobes, S.M.H.

    2009-01-01

    Songbirds, such as zebra finches, learn their songs from a ‘tutor’ (usually the father), early in life. There are strong parallels between the behavioural, cognitive and neural processes that underlie vocal learning in humans and songbirds. In both cases there is a sensitive period for auditory lear

  20. Auditory skills and brain morphology predict individual differences in adaptation to degraded speech.

    Science.gov (United States)

    Erb, Julia; Henry, Molly J; Eisner, Frank; Obleser, Jonas

    2012-07-01

    Noise-vocoded speech is a spectrally highly degraded signal, but it preserves the temporal envelope of speech. Listeners vary considerably in their ability to adapt to this degraded speech signal. Here, we hypothesised that individual differences in adaptation to vocoded speech should be predictable by non-speech auditory, cognitive, and neuroanatomical factors. We tested 18 normal-hearing participants in a short-term vocoded speech-learning paradigm (listening to 100 4-band-vocoded sentences). Non-speech auditory skills were assessed using amplitude modulation (AM) rate discrimination, where modulation rates were centred on the speech-relevant rate of 4 Hz. Working memory capacities were evaluated (digit span and nonword repetition), and structural MRI scans were examined for anatomical predictors of vocoded speech learning using voxel-based morphometry. Listeners who learned faster to understand degraded speech also showed smaller thresholds in the AM discrimination task. This ability to adjust to degraded speech is furthermore reflected anatomically in increased grey matter volume in an area of the left thalamus (pulvinar) that is strongly connected to the auditory and prefrontal cortices. Thus, individual non-speech auditory skills and left thalamus grey matter volume can predict how quickly a listener adapts to degraded speech.

  1. Thrombospondin 2-null mice display an altered brain foreign body response to polyvinyl alcohol sponge implants

    Energy Technology Data Exchange (ETDEWEB)

    Tian Weiming; Kyriakides, Themis R, E-mail: themis.kyriakides@yale.ed [Vascular Biology and Therapeutics Program, Departments of Pathology and Biomedical Engineering, Yale University, New Haven, CT 06519 (United States)

    2009-02-15

    Thrombospondin (TSP)-2 is a matricellular protein that participates in the processes of tissue repair and the foreign body response. In addition, TSP2 has been shown to influence synaptogenesis and recovery of the brain following stroke. In the present study we investigated the response following the implantation of polyvinyl alcohol (PVA) sponges in the brain. PVA sponges were implanted into the brain cortex of wild type and TSP2-null mice for a period of 4 and 8 weeks and the response was analyzed by histochemistry and quantitative immunohistochemistry. TSP2 expression was detected in the interstices of the sponge and co-localized with the extracellular matrix and astrocytes. PVA sponge invasion in TSP2-null mice was characterized by dense deposition of extracellular matrix and increased invasion of reactive astrocytes and macrophages/microglia. Furthermore, the angiogenic response was elevated and the detection of mouse serum albumin (MSA) in the brain cortex indicated excessive vessel leakage, suggesting that TSP2 plays a role in the repair/maintenance of the blood brain barrier. Finally, immunostaining demonstrated an increase in the levels of matrix metalloproteinase (MMP)-2 and MMP-9. Taken together, our observations support a role for TSP2 as critical determinant of the brain response to biomaterials.

  2. BDNF in Lower Brain Parts Modifies Auditory Fiber Activity to Gain Fidelity but Increases the Risk for Generation of Central Noise After Injury.

    Science.gov (United States)

    Chumak, Tetyana; Rüttiger, Lukas; Lee, Sze Chim; Campanelli, Dario; Zuccotti, Annalisa; Singer, Wibke; Popelář, Jiří; Gutsche, Katja; Geisler, Hyun-Soon; Schraven, Sebastian Philipp; Jaumann, Mirko; Panford-Walsh, Rama; Hu, Jing; Schimmang, Thomas; Zimmermann, Ulrike; Syka, Josef; Knipper, Marlies

    2016-10-01

    For all sensory organs, the establishment of spatial and temporal cortical resolution is assumed to be initiated by the first sensory experience and a BDNF-dependent increase in intracortical inhibition. To address the potential of cortical BDNF for sound processing, we used mice with a conditional deletion of BDNF in which Cre expression was under the control of the Pax2 or TrkC promoter. BDNF deletion profiles between these mice differ in the organ of Corti (BDNF (Pax2) -KO) versus the auditory cortex and hippocampus (BDNF (TrkC) -KO). We demonstrate that BDNF (Pax2) -KO but not BDNF (TrkC) -KO mice exhibit reduced sound-evoked suprathreshold ABR waves at the level of the auditory nerve (wave I) and inferior colliculus (IC) (wave IV), indicating that BDNF in lower brain regions but not in the auditory cortex improves sound sensitivity during hearing onset. Extracellular recording of IC neurons of BDNF (Pax2) mutant mice revealed that the reduced sensitivity of auditory fibers in these mice went hand in hand with elevated thresholds, reduced dynamic range, prolonged latency, and increased inhibitory strength in IC neurons. Reduced parvalbumin-positive contacts were found in the ascending auditory circuit, including the auditory cortex and hippocampus of BDNF (Pax2) -KO, but not of BDNF (TrkC) -KO mice. Also, BDNF (Pax2) -WT but not BDNF (Pax2) -KO mice did lose basal inhibitory strength in IC neurons after acoustic trauma. These findings suggest that BDNF in the lower parts of the auditory system drives auditory fidelity along the entire ascending pathway up to the cortex by increasing inhibitory strength in behaviorally relevant frequency regions. Fidelity and inhibitory strength can be lost following auditory nerve injury leading to diminished sensory outcome and increased central noise.

  3. A Stem Cell-Seeded Nanofibrous Scaffold for Auditory Nerve Replacement

    Science.gov (United States)

    2015-10-01

    Nanofibrous Substrate, Neural Hearing Loss ESCs - embryonic stem cells EBs - embryoid bodies SMADi - SMAD-inhibitors RA - retinoic acid Pur... embryoid bodies (EBs) are generated by spin-aggregation in a micropatterned plate and pushed toward a neuroectodermal fate using SMAD-inhibitors (SMADi...using a Pax2-reporter cell line. At day 0, mouse ESCs are aggregated into embryoid bodies using round-bottom 96-well plates. On day 1, growth

  4. Hypoxic-ischemic encephalopathy with cystic brain stem necroses and thalamic calcifications in a preterm twin.

    Science.gov (United States)

    Peters, B; Walka, M M; Friedmann, W; Stoltenburg-Didinger, G; Obladen, M

    2000-06-01

    A severe and rare ischemic brain lesion in a preterm twin boy is reported. The boy was born after two weeks of anhydramnios and amnionic infection at 24 weeks of gestation. Following a difficult Caesarean section and prolonged umbilical cord compression he developed prenatal acidosis with an umbilical cord pH of 6.96. At the age of 7 h, heart rate variability narrowed due to severely disturbed brain stem function and the patient developed clinical signs of hypoxic-ischemic encephalopathy. Sonography demonstrated extensive symmetrical brain stem and basal ganglia lesions. After a prolonged comatose and apneic state, death occurred at the age of 25 days. Autopsy confirmed columnar bilateral cavitation of basal ganglia, diencephalon, brain stem and spinal gray matter, as well as focal calcifications in the palladium, thalamus, and brain stem. The findings highly resemble those observed after experimental or clinical cardiac arrest.

  5. Biological effect of velvet antler polypeptides on neural stem cells from embryonic rat brain

    Institute of Scientific and Technical Information of China (English)

    LU Lai-jin; CHEN Lei; MENG Xiao-ting; YANG Fan; ZHANG Zhi-xin; CHEN Dong

    2005-01-01

    Background Velvet antler polypeptides (VAPs), which are derived from the antler velvets, have been reported to maintain survival and promote growth and differentiation of neural cells and, especially the development of neural tissues. This study was designed to explore the influence of VAPs on neural stem cells in vitro derived from embryonic rat brain. Methods Neural stem cells derived from E12-14 rat brain were isolated, cultured, and expanded for 7 days until neural stem cell aggregations and neurospheres were generated. The neurospheres were cultured under the condition of different concentration of VAPs followed by immunocytochemistry to detect the differentiation of neural stem cells. Results VAPs could remarkablely promote differentiation of neural stem cells and most neural stem cells were induced to differentiate towards the direction of neurons under certain concentration of VAPs.Conclusion Neural stem cells can be successfully induced into neurons by VAPs in vitro, which could provide a basis for regeneration of the nervous system.

  6. Neurodevelopment. Live imaging of adult neural stem cell behavior in the intact and injured zebrafish brain.

    Science.gov (United States)

    Barbosa, Joana S; Sanchez-Gonzalez, Rosario; Di Giaimo, Rossella; Baumgart, Emily Violette; Theis, Fabian J; Götz, Magdalena; Ninkovic, Jovica

    2015-05-15

    Adult neural stem cells are the source for restoring injured brain tissue. We used repetitive imaging to follow single stem cells in the intact and injured adult zebrafish telencephalon in vivo and found that neurons are generated by both direct conversions of stem cells into postmitotic neurons and via intermediate progenitors amplifying the neuronal output. We observed an imbalance of direct conversion consuming the stem cells and asymmetric and symmetric self-renewing divisions, leading to depletion of stem cells over time. After brain injury, neuronal progenitors are recruited to the injury site. These progenitors are generated by symmetric divisions that deplete the pool of stem cells, a mode of neurogenesis absent in the intact telencephalon. Our analysis revealed changes in the behavior of stem cells underlying generation of additional neurons during regeneration.

  7. An implantable device for neuropsychiatric rehabilitation by chronic deep brain stimulation in freely moving rats

    Science.gov (United States)

    Wang, Chenguang; Zhang, Fuqiang; Jia, Hong

    2017-01-01

    Successful practice of clinical deep brain stimulation (DBS) calls for basic research on the mechanisms and explorations of new indications in animals. In the article, a new implantable, single-channel, low-power miniature device is proposed, which may transmit pulses chronically into the brain nucleus of freely moving rats. The DBS system consists of an implantable pulse generator (IPG), a bipolar electrode, and an external programmer. The IPG circuit module is assembled as a 20-mm diameter circular board and fixed on a rat’s skull together with an electrode and battery. The rigid electrode may make its fabrication and implantation more easy. The external programmer is designed for bidirectional communication with the IPG by a telecontrol transceiver and adjusts stimulation parameters. A biological validation was performed in which the effects of electrical stimulation in brain nucleus accumbens were detected. The programmed parameters were accurate, implant steady, and power sufficient to allow stimulation for more than 3 months. The larger area of the electrode tip provided a moderate current or charge density and minimized the damage from electrochemistry and pyroelectricity. The rats implanted with the device showed a reduction in morphine-induced conditioned place preference after high-frequency stimulation. In conclusion, the DBS device is based on the criteria of simple technology, minimal invasion, low cost, small in size, light-weight, and wireless controlled. This shows that our DBS device is appropriate and can be used for preclinical studies, indicating its potential utility in the therapy and rehabilitation of neuropsychiatric disorders. PMID:28121810

  8. Breaking the Blood-Brain Barrier With Mannitol to Aid Stem Cell Therapeutics in the Chronic Stroke Brain.

    Science.gov (United States)

    Tajiri, Naoki; Lee, Jea Young; Acosta, Sandra; Sanberg, Paul R; Borlongan, Cesar V

    2016-01-01

    Blood-brain barrier (BBB) permeabilizers, such as mannitol, can facilitate peripherally delivered stem cells to exert therapeutic benefits on the stroke brain. Although this BBB permeation-aided stem cell therapy has been demonstrated in the acute stage of stroke, such BBB permeation in the chronic stage of the disease remains to be examined. Adult Sprague-Dawley rats initially received sham surgery or experimental stroke via the 1-h middle cerebral artery occlusion (MCAo) model. At 1 month after the MCAo surgery, stroke animals were randomly assigned to receive human umbilical cord stem cells only (2 million viable cells), mannitol only (1.1 mol/L mannitol at 4°C), combined human umbilical cord stem cells (200,000 viable cells) and mannitol (1.1 mol/L mannitol at 4°C), and vehicle (phosphate-buffered saline) only. Stroke animals that received human umbilical cord blood cells alone or combined human umbilical cord stem cells and mannitol exhibited significantly improved motor performance and significantly better brain cell survival in the peri-infarct area compared to stroke animals that received vehicle or mannitol alone, with mannitol treatment reducing the stem cell dose necessary to afford functional outcomes. Enhanced neurogenesis in the subventricular zone accompanied the combined treatment of human umbilical cord stem cells and mannitol. We showed that BBB permeation facilitates the therapeutic effects of a low dose of peripherally transplanted stem cells to effectively cause functional improvement and increase neurogenesis in chronic stroke.

  9. A trade-off between somatosensory and auditory related brain activity during object naming but not reading.

    Science.gov (United States)

    Seghier, Mohamed L; Hope, Thomas M H; Prejawa, Susan; Parker Jones, 'Ōiwi; Vitkovitch, Melanie; Price, Cathy J

    2015-03-18

    The parietal operculum, particularly the cytoarchitectonic area OP1 of the secondary somatosensory area (SII), is involved in somatosensory feedback. Using fMRI with 58 human subjects, we investigated task-dependent differences in SII/OP1 activity during three familiar speech production tasks: object naming, reading and repeatedly saying "1-2-3." Bilateral SII/OP1 was significantly suppressed (relative to rest) during object naming, to a lesser extent when repeatedly saying "1-2-3" and not at all during reading. These results cannot be explained by task difficulty but the contrasting difference between naming and reading illustrates how the demands on somatosensory activity change with task, even when motor output (i.e., production of object names) is matched. To investigate what determined SII/OP1 deactivation during object naming, we searched the whole brain for areas where activity increased as that in SII/OP1 decreased. This across subject covariance analysis revealed a region in the right superior temporal sulcus (STS) that lies within the auditory cortex, and is activated by auditory feedback during speech production. The tradeoff between activity in SII/OP1 and STS was not observed during reading, which showed significantly more activation than naming in both SII/OP1 and STS bilaterally. These findings suggest that, although object naming is more error prone than reading, subjects can afford to rely more or less on somatosensory or auditory feedback during naming. In contrast, fast and efficient error-free reading places more consistent demands on both types of feedback, perhaps because of the potential for increased competition between lexical and sublexical codes at the articulatory level.

  10. Evaluating auditory stream segregation of SAM tone sequences by subjective and objective psychoacoustical tasks, and brain activity

    Directory of Open Access Journals (Sweden)

    Lena-Vanessa eDollezal

    2014-06-01

    Full Text Available Auditory stream segregation refers to a segregated percept of signal streams with different acoustic features. Different approaches have been pursued in studies of stream segregation. In psychoacoustics, stream segregation has mostly been investigated with a subjective task asking the subjects to report their percept. Few studies have applied an objective task in which stream segregation is evaluated indirectly by determining thresholds for a percept that depends on whether auditory streams are segregated or not. Furthermore, both perceptual measures and physiological measures of brain activity have been employed but only little is known about their relation. How the results from different tasks and measures are related is evaluated in the present study using examples relying on the ABA- stimulation paradigm that apply the same stimuli. We presented A and B signals that were sinusoidally amplitude modulated (SAM tones providing purely temporal, spectral or both types of cues to evaluate perceptual stream segregation and its physiological correlate. Which types of cues are most prominent was determined by the choice of carrier and modulation frequencies (fmod of the signals. In the subjective task subjects reported their percept and in the objective task we measured their sensitivity for detecting time-shifts of B signals in an ABA- sequence. As a further measure of processes underlying stream segregation we employed functional magnetic resonance imaging (fMRI. SAM tone parameters were chosen to evoke an integrated (1-stream, a segregated (2-stream or an ambiguous percept by adjusting the fmod difference between A and B tones (∆fmod. The results of both psychoacoustical tasks are significantly correlated. BOLD responses in fMRI depend on ∆fmod between A and B SAM tones. The effect of ∆fmod, however, differs between auditory cortex and frontal regions suggesting differences in representation related to the degree of perceptual ambiguity of

  11. Cyclosporin safety in a simplified rat brain tumor implantation model

    Directory of Open Access Journals (Sweden)

    Francisco H. C. Felix

    2012-01-01

    Full Text Available Brain cancer is the second neurological cause of death. A simplified animal brain tumor model using W256 (carcinoma 256, Walker cell line was developed to permit the testing of novel treatment modalities. Wistar rats had a cell tumor solution inoculated stereotactically in the basal ganglia (right subfrontal caudate. This model yielded tumor growth in 95% of the animals, and showed absence of extracranial metastasis and systemic infection. Survival median was 10 days. Estimated tumor volume was 17.08±6.7 mm³ on the 7th day and 67.25±19.8 mm³ on 9th day post-inoculation. Doubling time was 24.25 h. Tumor growth induced cachexia, but no hematological or biochemical alterations. This model behaved as an undifferentiated tumor and can be promising for studying tumor cell migration in the central nervous system. Dexamethasone 3.0 mg/kg/day diminished significantly survival in this model. Cyclosporine 10 mg/kg/day administration was safely tolerated.

  12. Aging, Cognitive Decline and Hearing Loss: Effects of Auditory Rehabilitation and Training with Hearing Aids and Cochlear Implants on Cognitive Function and Depression among Older Adults.

    Science.gov (United States)

    Castiglione, Alessandro; Benatti, Alice; Velardita, Carmelita; Favaro, Diego; Padoan, Elisa; Severi, Daniele; Pagliaro, Michela; Bovo, Roberto; Vallesi, Antonino; Gabelli, Carlo; Martini, Alessandro

    2016-01-01

    A growing interest in cognitive effects associated with speech and hearing processes is spreading throughout the scientific community essentially guided by evidence that central and peripheral hearing loss is associated with cognitive decline. For the present research, 125 participants older than 65 years of age (105 with hearing impairment and 20 with normal hearing) were enrolled, divided into 6 groups according to their degree of hearing loss and assessed to determine the effects of the treatment applied. Patients in our research program routinely undergo an extensive audiological and cognitive evaluation protocol providing results from the Digit Span test, Stroop color-word test, Montreal Cognitive Assessment and Geriatric Depression Scale, before and after rehabilitation. Data analysis was performed for a cross-sectional and longitudinal study of the outcomes for the different treatment groups. Each group demonstrated improvement after auditory rehabilitation or training on short- and long-term memory tasks, level of depression and cognitive status scores. Auditory rehabilitation by cochlear implants or hearing aids is effective also among older adults (median age of 74 years) with different degrees of hearing loss, and enables positive improvements in terms of social isolation, depression and cognitive performance.

  13. Functional brain fluorescence plurimetry in rat by implantable concatenated CMOS imaging system.

    Science.gov (United States)

    Kobayashi, Takuma; Masuda, Hiroyuki; Kitsumoto, Chikara; Haruta, Makito; Motoyama, Mayumi; Ohta, Yasumi; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Shiosaka, Sadao; Ohta, Jun

    2014-03-15

    Measurement of brain activity in multiple areas simultaneously by minimally invasive methods contributes to the study of neuroscience and development of brain machine interfaces. However, this requires compact wearable instruments that do not inhibit natural movements. Application of optical potentiometry with voltage-sensitive fluorescent dye using an implantable image sensor is also useful. However, the increasing number of leads required for the multiple wired sensors to measure larger domains inhibits natural behavior. For imaging broad areas by numerous sensors without excessive wiring, a web-like sensor that can wrap the brain was developed. Kaleidoscopic potentiometry is possible using the imaging system with concatenated sensors by changing the alignment of the sensors. This paper describes organization of the system, evaluation of the system by a fluorescence imaging, and finally, functional brain fluorescence plurimetry by the sensor. The recorded data in rat somatosensory cortex using the developed multiple-area imaging system compared well with electrophysiology results.

  14. [Abscess at the implant site following apical parodontitis. Hardware-related complications of deep brain stimulation].

    Science.gov (United States)

    Sixel-Döring, F; Trenkwalder, C; Kappus, C; Hellwig, D

    2006-08-01

    Deep brain stimulation of the subthalamic nucleus is an important treatment option for advanced stages of idiopathic Parkinson's disease, leading to significant improvement of motor symptoms in suited patients. Hardware-related complications such as technical malfunction, skin erosion, and infections however cause patient discomfort and additional expense. The patient presented here suffered a putrid infection of the impulse generator site following only local dental treatment of apical parodontitis. Therefore, prophylactic systemic antibiotic treatment is recommended for patients with implanted deep brain stimulation devices in case of operations, dental procedures, or infectious disease.

  15. Cochlear Implant Outcomes and Genetic Mutations in Children with Ear and Brain Anomalies

    OpenAIRE

    Micol Busi; Monica Rosignoli; Alessandro Castiglione; Federica Minazzi; Patrizia Trevisi; Claudia Aimoni; Ferdinando Calzolari; Enrico Granieri; Alessandro Martini

    2015-01-01

    Background. Specific clinical conditions could compromise cochlear implantation outcomes and drastically reduce the chance of an acceptable development of perceptual and linguistic capabilities. These conditions should certainly include the presence of inner ear malformations or brain abnormalities. The aims of this work were to study the diagnostic value of high resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) in children with sensorineural hearing loss who were can...

  16. Electromagnetic interference of GSM mobile phones with the implantable deep brain stimulator, ITREL-III

    Directory of Open Access Journals (Sweden)

    Alesch François

    2003-05-01

    Full Text Available Abstract Background The purpose was to investigate mobile phone interference with implantable deep brain stimulators by means of 10 different 900 Mega Hertz (MHz and 10 different 1800 MHz GSM (Global System for Mobile Communications mobile phones. Methods All tests were performed in vitro using a phantom especially developed for testing with deep brain stimulators. The phantom was filled with liquid phantom materials simulating brain and muscle tissue. All examinations were carried out inside an anechoic chamber on two implants of the same type of deep brain stimulator: ITREL-III from Medtronic Inc., USA. Results Despite a maximum transmitted peak power of mobile phones of 1 Watt (W at 1800 MHz and 2 W at 900 MHz respectively, no influence on the ITREL-III was found. Neither the shape of the pulse form changed nor did single pulses fail. Tests with increased transmitted power using CW signals and broadband dipoles have shown that inhibition of the ITREL-III occurs at frequency dependent power levels which are below the emissions of GSM mobile phones. The ITREL-III is essentially more sensitive at 1800 MHz than at 900 MHz. Particularly the frequency range around 1500 MHz shows a very low interference threshold. Conclusion These investigations do not indicate a direct risk for ITREL-III patients using the tested GSM phones. Based on the interference levels found with CW signals, which are below the mobile phone emissions, we recommend similar precautions as for patients with cardiac pacemakers: 1. The phone should be used at the ear at the opposite side of the implant and 2. The patient should avoid carrying the phone close to the implant.

  17. Brain networks of novelty-driven involuntary and cued voluntary auditory attention shifting.

    Science.gov (United States)

    Huang, Samantha; Belliveau, John W; Tengshe, Chinmayi; Ahveninen, Jyrki

    2012-01-01

    In everyday life, we need a capacity to flexibly shift attention between alternative sound sources. However, relatively little work has been done to elucidate the mechanisms of attention shifting in the auditory domain. Here, we used a mixed event-related/sparse-sampling fMRI approach to investigate this essential cognitive function. In each 10-sec trial, subjects were instructed to wait for an auditory "cue" signaling the location where a subsequent "target" sound was likely to be presented. The target was occasionally replaced by an unexpected "novel" sound in the uncued ear, to trigger involuntary attention shifting. To maximize the attention effects, cues, targets, and novels were embedded within dichotic 800-Hz vs. 1500-Hz pure-tone "standard" trains. The sound of clustered fMRI acquisition (starting at t = 7.82 sec) served as a controlled trial-end signal. Our approach revealed notable activation differences between the conditions. Cued voluntary attention shifting activated the superior intra--parietal sulcus (IPS), whereas novelty-triggered involuntary orienting activated the inferior IPS and certain subareas of the precuneus. Clearly more widespread activations were observed during voluntary than involuntary orienting in the premotor cortex, including the frontal eye fields. Moreover, we found -evidence for a frontoinsular-cingular attentional control network, consisting of the anterior insula, inferior frontal cortex, and medial frontal cortices, which were activated during both target discrimination and voluntary attention shifting. Finally, novels and targets activated much wider areas of superior temporal auditory cortices than shifting cues.

  18. Mg ion implantation on SLA-treated titanium surface and its effects on the behavior of mesenchymal stem cell.

    Science.gov (United States)

    Kim, Beom-Su; Kim, Jin Seong; Park, Young Min; Choi, Bo-Young; Lee, Jun

    2013-04-01

    Magnesium (Mg) is one of the most important ions associated with bone osseointegration. The aim of this study was to evaluate the cellular effects of Mg implantation in titanium (Ti) surfaces treated with sand blast using large grit and acid etching (SLA). Mg ions were implanted into the surface via vacuum arc source ion implantation. The surface morphology, chemical properties, and the amount of Mg ion release were evaluated by scanning electron microscopy (SEM), Auger electron spectroscopy (AES), Rutherford backscattering spectroscopy (RBS), and inductively coupled plasma-optical emission spectrometer (ICP-OES). Human mesenchymal stem cells (hMSCs) were used to evaluate cellular parameters such as proliferation, cytotoxicity, and adhesion morphology by MTS assay, live/dead assay, and SEM. Furthermore, osteoblast differentiation was determined on the basis of alkaline phosphatase (ALP) activity and the degree of calcium accumulation. In the Mg ion-implanted disk, 2.3×10(16) ions/cm(2) was retained. However, after Mg ion implantation, the surface morphology did not change. Implanted Mg ions were rapidly released during the first 7 days in vitro. The MTS assay, live/dead assay, and SEM demonstrated increased cell attachment and growth on the Mg ion-implanted surface. In particular, Mg ion implantation increased the initial cell adhesion, and in an osteoblast differentiation assay, ALP activity and calcium accumulation. These findings suggest that Mg ion implantation using the plasma source ion implantation (PSII) technique may be useful for SLA-treated Ti dental implants to improve their osseointegration capacity.

  19. NFL-lipid nanocapsules for brain neural stem cell targeting in vitro and in vivo.

    Science.gov (United States)

    Carradori, Dario; Saulnier, Patrick; Préat, Véronique; des Rieux, Anne; Eyer, Joel

    2016-09-28

    The replacement of injured neurons by the selective stimulation of neural stem cells in situ represents a potential therapeutic strategy for the treatment of neurodegenerative diseases. The peptide NFL-TBS.40-63 showed specific interactions towards neural stem cells of the subventricular zone. The aim of our work was to produce a NFL-based drug delivery system able to target neural stem cells through the selective affinity between the peptide and these cells. NFL-TBS.40-63 (NFL) was adsorbed on lipid nanocapsules (LNC) whom targeting efficiency was evaluated on neural stem cells from the subventricular zone (brain) and from the central canal (spinal cord). NFL-LNC were incubated with primary neural stem cells in vitro or injected in vivo in adult rat brain (right lateral ventricle) or spinal cord (T10). NFL-LNC interactions with neural stem cells were different depending on the origin of the cells. NFL-LNC showed a preferential uptake by neural stem cells from the brain, while they did not interact with neural stem cells from the spinal cord. The results obtained in vivo correlate with the results observed in vitro, demonstrating that NFL-LNC represent a promising therapeutic strategy to selectively deliver bioactive molecules to brain neural stem cells.

  20. Further In-vitro Characterization of an Implantable Biosensor for Ethanol Monitoring in the Brain

    Directory of Open Access Journals (Sweden)

    Gaia Rocchitta

    2013-07-01

    Full Text Available Ethyl alcohol may be considered one of the most widespread central nervous system (CNS depressants in Western countries. Because of its toxicological and neurobiological implications, the detection of ethanol in brain extracellular fluid (ECF is of great importance. In a previous study, we described the development and characterization of an implantable biosensor successfully used for the real-time detection of ethanol in the brain of freely-moving rats. The implanted biosensor, integrated in a low-cost telemetry system, was demonstrated to be a reliable device for the short-time monitoring of exogenous ethanol in brain ECF. In this paper we describe a further in-vitro characterization of the above-mentioned biosensor in terms of oxygen, pH and temperature dependence in order to complete its validation. With the aim of enhancing ethanol biosensor performance, different enzyme loadings were investigated in terms of apparent ethanol Michaelis-Menten kinetic parameters, viz. IMAX, KM and linear region slope, as well as ascorbic acid interference shielding. The responses of biosensors were studied over a period of 28 days. The overall findings of the present study confirm the original biosensor configuration to be the best of those investigated for in-vivo applications up to one week after implantation.

  1. Evaluation of intra-operative EABR characteristics and rehabilitation effects of cochlear implantation in patients with internal auditory canal stenosis%内耳道狭窄患者人工耳蜗术中EABR特点及术后疗效评估

    Institute of Scientific and Technical Information of China (English)

    金毅; 曹克利; 魏朝刚; 王斌

    2013-01-01

    目的:探讨内耳道狭窄患者电刺激听觉脑干诱发电位(EABR)的特点及与人工耳蜗植入术后听力言语康复效果的关系.方法:回顾性分析内耳道狭窄(IACS)的语前聋人工耳蜗植入患者16例(IACS组),筛选条件相近的16例内耳道解剖结构正常的语前聋人工耳蜗植入者配对(对照组),术中人工耳蜗植入前采用EABR评估听觉传导通路,记录EABR波形、阈值和动态范围;对患者家长和康复教师进行调查随访,根据听觉行为分级标准(CAP)和言语可懂度分级标准(SIR)对患者听力言语康复效果分级评估.采用配对样本T检验比较术前和术后1年患者CAP和SIR评分,Spearman检验对术中EABR分级和术后CAP评分进行相关性分析.结果:IACS组2例患者术中未记录到典型EABR波形,术后开机无反应.IACS组EABR波形分化差于对照组,其EABR阈值(192.5±11.73)高于对照组(168.75±6.94),动态范围(32.50±19.69)小于对照组(80.63±9.04).术后1年IACS的听觉言语康复效果的CAP和SIR值分别为3.47±1.09、1.62±0.50,得分均低于对照组(分别为5.06±0.79、2.59±0.58),差异有统计学意义(均P<0.05).术中EABR分级和术后CAP评分具有明显相关性(r=0.78,P<0.05).结论:EABR能够较准确地反映听觉传导通路功能的完整性,有利于判断内耳道狭窄患者人工耳蜗植入后能否获得听觉反应.EABR辅助人工耳蜗植入前的全面评估,内耳道狭窄患者的听觉言语能力可得到不同程度的康复.%Objective:To investigate the intra-operative electrical evoked auditory brain stem response(EABR) characteristics and the hearing and speech rehabilitation effects of cochlear implantation(CI) in patients with internal auditory canal stenosis(IACS).Method:A retrospective study was performed on 16 patients with IACS (IACS group) matched with 16 implantees without IACS(control group),who received multi-channel CI because of prelingual sensorineural hearing loss

  2. SU-E-T-570: Management of Radiation Oncology Patients with Cochlear Implant and Other Bionic Devices in the Brain and Head and Neck Regions

    Energy Technology Data Exchange (ETDEWEB)

    Guo, F.Q; Chen, Z; Nath, R [Yale New Haven Hospital, New Haven, CT (United States); Yale UniversitySchool of Medicine, New Haven, CT (United States)

    2014-06-01

    Purpose: To investigate the current status of clinical usage of cochlear implant (CI) and other bionic devices (BD) in the brain and head and neck regions (BH and N) and their management in patients during radiotherapy to ensure patient health and safety as well as optimum radiation delivery. Methods: Literature review was performed with both CIs and radiotherapy and their variants as keywords in PubMed, INSPEC and other sources. The focus was on CIs during radiotherapy, but it also included other BDs in BHȦN, such as auditory brainstem implant, bionic retinal implant, and hearing aids, among others. Results: Interactions between CIs and radiation may cause CIs malfunction. The presence of CIs may also cause suboptimum dose distribution if a treatment plan was not well designed. A few studies were performed for the hearing functions of CIs under irradiations of 4 MV and 6 MV x-rays. However, x-rays with higher energies (10 to 18 MV) broadly used in radiotherapy have not been explored. These higher energetic beams are more damaging to electronics due to strong penetrating power and also due to neutrons generated in the treatment process. Modern CIs are designed with more and more complicated integrated circuits, which may be more susceptible to radiation damage and malfunction. Therefore, careful management is important for safety and treatment outcomes. Conclusion: Although AAPM TG-34, TG-63, and TG-203 (update of TG-34, not published yet) reports may be referenced for management of CIs and other BDs in the brain and H and N regions, a site- and device-specified guideline should be developed for CIs and other BDs. Additional evaluation of CI functions under clinically relevant set-ups should also be performed to provide clinicians with better knowledge in clinical decision making.

  3. Processing of species-specific auditory patterns in the cricket brain by ascending, local, and descending neurons during standing and walking.

    Science.gov (United States)

    Zorović, M; Hedwig, B

    2011-05-01

    The recognition of the male calling song is essential for phonotaxis in female crickets. We investigated the responses toward different models of song patterns by ascending, local, and descending neurons in the brain of standing and walking crickets. We describe results for two ascending, three local, and two descending interneurons. Characteristic dendritic and axonal arborizations of the local and descending neurons indicate a flow of auditory information from the ascending interneurons toward the lateral accessory lobes and point toward the relevance of this brain region for cricket phonotaxis. Two aspects of auditory processing were studied: the tuning of interneuron activity to pulse repetition rate and the precision of pattern copying. Whereas ascending neurons exhibited weak, low-pass properties, local neurons showed both low- and band-pass properties, and descending neurons represented clear band-pass filters. Accurate copying of single pulses was found at all three levels of the auditory pathway. Animals were walking on a trackball, which allowed an assessment of the effect that walking has on auditory processing. During walking, all neurons were additionally activated, and in most neurons, the spike rate was correlated to walking velocity. The number of spikes elicited by a chirp increased with walking only in ascending neurons, whereas the peak instantaneous spike rate of the auditory responses increased on all levels of the processing pathway. Extra spiking activity resulted in a somewhat degraded copying of the pulse pattern in most neurons.

  4. Estimating the intended sound direction of the user: toward an auditory brain-computer interface using out-of-head sound localization.

    Directory of Open Access Journals (Sweden)

    Isao Nambu

    Full Text Available The auditory Brain-Computer Interface (BCI using electroencephalograms (EEG is a subject of intensive study. As a cue, auditory BCIs can deal with many of the characteristics of stimuli such as tone, pitch, and voices. Spatial information on auditory stimuli also provides useful information for a BCI. However, in a portable system, virtual auditory stimuli have to be presented spatially through earphones or headphones, instead of loudspeakers. We investigated the possibility of an auditory BCI using the out-of-head sound localization technique, which enables us to present virtual auditory stimuli to users from any direction, through earphones. The feasibility of a BCI using this technique was evaluated in an EEG oddball experiment and offline analysis. A virtual auditory stimulus was presented to the subject from one of six directions. Using a support vector machine, we were able to classify whether the subject attended the direction of a presented stimulus from EEG signals. The mean accuracy across subjects was 70.0% in the single-trial classification. When we used trial-averaged EEG signals as inputs to the classifier, the mean accuracy across seven subjects reached 89.5% (for 10-trial averaging. Further analysis showed that the P300 event-related potential responses from 200 to 500 ms in central and posterior regions of the brain contributed to the classification. In comparison with the results obtained from a loudspeaker experiment, we confirmed that stimulus presentation by out-of-head sound localization achieved similar event-related potential responses and classification performances. These results suggest that out-of-head sound localization enables us to provide a high-performance and loudspeaker-less portable BCI system.

  5. Detection of neural stem cells function in rats with traumatic brain injury by manganese-enhanced magnetic resonance imaging

    Institute of Scientific and Technical Information of China (English)

    TANG Hai-liang; SUN Hua-ping; WU Xing; SHA Hong-ying; FENG Xiao-yuan; ZHU Jian-hong

    2011-01-01

    Background Previously we had successfully tracked adult human neural stem cells (NSCs) labeled with superparamagnetic iron oxide particles (SPIOs) in host human brain after transplantation In vivo non-invasively by magnetic resonance imaging (MRI). However, the function of the transplanted NSCs could not be evaluated by the method. In the study, we applied manganese-enhanced MRI (ME-MRI) to detect NSCs function after implantation in brain of rats with traumatic brain injury (TBI) In vivo.Methods Totally 40 TBI rats were randomly divided into 4 groups with 10 rats in each group. In group 1, the TBI rats did not receive NSCs transplantation. MnCl2-4H2O was intravenously injected, hyperosmolar mannitol was delivered to disrupt rightside blood brain barrier, and its contralateral forepaw was electrically stimulated. In group 2, the TBI rats received NSCs (labeled with SPIO) transplantation, and the ME-MRI procedure was same to group 1. In group 3, the TBI rats received NSCs (labeled with SPIO) transplantation, and the ME-MRI procedure was same to group 1, but diltiazem was introduced during the electrical stimulation period. In group 4, the TBI rats received phosphate buffered saline (PBS) injection, and the ME-MRI procedure was same to group 1.Results Hyperintense signals were detected by ME-MRI in the cortex areas associated with somatosensory in TBI rats of group 2. These signals, which could not be induced in TBI rats of groups 1 and 4, disappeared when diltiazem was introduced in TBI rats of group 3.Conclusion In this initial study, we mapped implanted NSCs activity and its functional participation within local brain area in TBI rats by ME-MRI technique, paving the way for further pre-clinical research.

  6. Electro-Acupuncture for Treatment of Dysequillibrium Due to Cerebellum or Brain Stem Infarction

    Institute of Scientific and Technical Information of China (English)

    赵宏; 刘志顺; 刘效娟

    2003-01-01

    @@ The authors treated 26 cases of dysequillibrium due tocerebellum or brain stem infarction byelectro-acupuncture from Aug 2000 - April 2002. Theresults were quite satisfactory and reported as follows.

  7. Schwann Cells Transplantation Promoted and the Repair of Brain Stem Injury in Rats

    Institute of Scientific and Technical Information of China (English)

    HONG WAN; YI-HUA AN; MEI-ZHEN SUN; YA-ZHUO ZHANG; ZHONG-CHENG WANG

    2003-01-01

    To explore the possibility of Schwann cells transplantation to promote the repair of injured brain stem reticular structure in rats. Methods Schwann cells originated from sciatic nerves of 1 to 2-day-old rats were expanded and labelled by BrdU in vitro, transplanted into rat brain stem reticular structure that was pre-injured by electric needle stimulus. Immunohistochemistry and myelin-staining were used to investigate the expression of BrdU, GAP-43 and new myelination respectively. Results BrdU positive cells could be identified for up to 8 months and their number increased by about 23%, which mainly migrated toward injured ipsilateral cortex. The GAP-43expression reached its peak in 1 month after transplantation and was significantly higher than that in the control group. New myelination could be seen in destructed brain stem areas. Conclusion The transplantation of Schwann cells can promote the restoration of injured brain stem reticular structure.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

  9. Brain activity underlying auditory perceptual learning during short period training: simultaneous fMRI and EEG recording

    Directory of Open Access Journals (Sweden)

    de Souza Ana Cláudia Silva

    2013-01-01

    Full Text Available Abstract Background There is an accumulating body of evidence indicating that neuronal functional specificity to basic sensory stimulation is mutable and subject to experience. Although fMRI experiments have investigated changes in brain activity after relative to before perceptual learning, brain activity during perceptual learning has not been explored. This work investigated brain activity related to auditory frequency discrimination learning using a variational Bayesian approach for source localization, during simultaneous EEG and fMRI recording. We investigated whether the practice effects are determined solely by activity in stimulus-driven mechanisms or whether high-level attentional mechanisms, which are linked to the perceptual task, control the learning process. Results The results of fMRI analyses revealed significant attention and learning related activity in left and right superior temporal gyrus STG as well as the left inferior frontal gyrus IFG. Current source localization of simultaneously recorded EEG data was estimated using a variational Bayesian method. Analysis of current localized to the left inferior frontal gyrus and the right superior temporal gyrus revealed gamma band activity correlated with behavioral performance. Conclusions Rapid improvement in task performance is accompanied by plastic changes in the sensory cortex as well as superior areas gated by selective attention. Together the fMRI and EEG results suggest that gamma band activity in the right STG and left IFG plays an important role during perceptual learning.

  10. Long-range correlation properties in timing of skilled piano performance: the influence of auditory feedback and deep brain stimulation.

    Directory of Open Access Journals (Sweden)

    Maria eHerrojo Ruiz

    2014-09-01

    Full Text Available Unintentional timing deviations during musical performance can be conceived of as timing errors. However, recent research on humanizing computer-generated music has demonstrated that timing fluctuations that exhibit long-range temporal correlations (LRTC are preferred by human listeners. This preference can be accounted for by the ubiquitous presence of LRTC in human tapping and rhythmic performances. Interestingly, the manifestation of LRTC in tapping behavior seems to be driven in a subject-specific manner by the LRTC properties of resting-state background cortical oscillatory activity. In this framework, the current study aimed to investigate whether propagation of timing deviations during the skilled, memorized piano performance (without metronome of 17 professional pianists exhibits LRTC and whether the structure of the correlations is influenced by the presence or absence of auditory feedback.As an additional goal, we set out to investigate the influence of altering the dynamics along the cortico-basal-ganglia-thalamo-cortical network via deep brain stimulation (DBS on the LRTC properties of musical performance. Specifically, we investigated temporal deviations during the skilled piano performance of a non-professional pianist who was treated with subthalamic-deep brain stimulation (STN-DBS due to severe Parkinson's disease, with predominant tremor affecting his right upper extremity. In the tremor-affected right hand, the timing fluctuations of the performance exhibited random correlations with DBS OFF. By contrast, DBS restored long-range dependency in the temporal fluctuations, corresponding with the general motor improvement on DBS.Overall, the present investigations are the first to demonstrate the presence of LRTC in skilled piano performances, indicating that unintentional temporal deviations are correlated over a wide range of time scales. This phenomenon is stable after removal of the auditory feedback, but is altered by STN

  11. Long-range correlation properties in timing of skilled piano performance: the influence of auditory feedback and deep brain stimulation.

    Science.gov (United States)

    Herrojo Ruiz, María; Hong, Sang Bin; Hennig, Holger; Altenmüller, Eckart; Kühn, Andrea A

    2014-01-01

    Unintentional timing deviations during musical performance can be conceived of as timing errors. However, recent research on humanizing computer-generated music has demonstrated that timing fluctuations that exhibit long-range temporal correlations (LRTC) are preferred by human listeners. This preference can be accounted for by the ubiquitous presence of LRTC in human tapping and rhythmic performances. Interestingly, the manifestation of LRTC in tapping behavior seems to be driven in a subject-specific manner by the LRTC properties of resting-state background cortical oscillatory activity. In this framework, the current study aimed to investigate whether propagation of timing deviations during the skilled, memorized piano performance (without metronome) of 17 professional pianists exhibits LRTC and whether the structure of the correlations is influenced by the presence or absence of auditory feedback. As an additional goal, we set out to investigate the influence of altering the dynamics along the cortico-basal-ganglia-thalamo-cortical network via deep brain stimulation (DBS) on the LRTC properties of musical performance. Specifically, we investigated temporal deviations during the skilled piano performance of a non-professional pianist who was treated with subthalamic-deep brain stimulation (STN-DBS) due to severe Parkinson's disease, with predominant tremor affecting his right upper extremity. In the tremor-affected right hand, the timing fluctuations of the performance exhibited random correlations with DBS OFF. By contrast, DBS restored long-range dependency in the temporal fluctuations, corresponding with the general motor improvement on DBS. Overall, the present investigations demonstrate the presence of LRTC in skilled piano performances, indicating that unintentional temporal deviations are correlated over a wide range of time scales. This phenomenon is stable after removal of the auditory feedback, but is altered by STN-DBS, which suggests that cortico

  12. Recruited brain tumor-derived mesenchymal stem cells contribute to brain tumor progression.

    Science.gov (United States)

    Behnan, Jinan; Isakson, Pauline; Joel, Mrinal; Cilio, Corrado; Langmoen, Iver A; Vik-Mo, Einar O; Badn, Wiaam

    2014-05-01

    The identity of the cells that contribute to brain tumor structure and progression remains unclear. Mesenchymal stem cells (MSCs) have recently been isolated from normal mouse brain. Here, we report the infiltration of MSC-like cells into the GL261 murine glioma model. These brain tumor-derived mesenchymal stem cells (BT-MSCs) are defined with the phenotype (Lin-Sca-1+CD9+CD44+CD166+/-) and have multipotent differentiation capacity. We show that the infiltration of BT-MSCs correlates to tumor progression; furthermore, BT-MSCs increased the proliferation rate of GL261 cells in vitro. For the first time, we report that the majority of GL261 cells expressed mesenchymal phenotype under both adherent and sphere culture conditions in vitro and that the non-MSC population is nontumorigenic in vivo. Although the GL261 cell line expressed mesenchymal phenotype markers in vitro, most BT-MSCs are recruited cells from host origin in both wild-type GL261 inoculated into green fluorescent protein (GFP)-transgenic mice and GL261-GFP cells inoculated into wild-type mice. We show the expression of chemokine receptors CXCR4 and CXCR6 on different recruited cell populations. In vivo, the GL261 cells change marker profile and acquire a phenotype that is more similar to cells growing in sphere culture conditions. Finally, we identify a BT-MSC population in human glioblastoma that is CD44+CD9+CD166+ both in freshly isolated and culture-expanded cells. Our data indicate that cells with MSC-like phenotype infiltrate into the tumor stroma and play an important role in tumor cell growth in vitro and in vivo. Thus, we suggest that targeting BT-MSCs could be a possible strategy for treating glioblastoma patients.

  13. Possible role of brain stem respiratory neurons in mediating vomiting during space motion sickness

    Science.gov (United States)

    Miller, A. D.; Tan, L. K.

    1987-01-01

    The object of this study was to determine if brain stem expiratory neurons control abdominal muscle activity during vomiting. The activity of 27 ventral respiratory group expiratory neurons, which are known to be of primary importance for control of abdominal muscle activity during respiration, was recorded. It is concluded that abdominal muscle activity during vomiting must be controlled not only by some brain stem expiratory neurons but also by other input(s).

  14. MR imaging features of gadofluorine-labeled matrix-associated stem cell implants in cartilage defects.

    Directory of Open Access Journals (Sweden)

    Hossein Nejadnik

    Full Text Available OBJECTIVES: The purpose of our study was to assess the chondrogenic potential and the MR signal effects of GadofluorineM-Cy labeled matrix associated stem cell implants (MASI in pig knee specimen. MATERIALS AND METHODS: Human mesenchymal stem cells (hMSCs were labeled with the micelle-based contrast agent GadofluorineM-Cy. Ferucarbotran-labeled hMSCs, non-labeled hMSCs and scaffold only served as controls. Chondrogenic differentiation was induced and gene expression and histologic evaluation were performed. The proportions of spindle-shaped vs. round cells of chondrogenic pellets were compared between experimental groups using the Fisher's exact test. Labeled and unlabeled hMSCs and chondrocytes in scaffolds were implanted into cartilage defects of porcine femoral condyles and underwent MR imaging with T1- and T2-weighted SE and GE sequences. Contrast-to-noise ratios (CNR between implants and adjacent cartilage were determined and analyzed for significant differences between different experimental groups using the Kruskal-Wallis test. Significance was assigned for p0.017. However, hMSC differentiation into chondrocytes was superior for unlabeled and GadofluorineM-Cy-labeled cells compared with Ferucarbotran-labeled cells, as evidenced by a significantly higher proportion of spindle cells in chondrogenic pellets (p<0.05. GadofluorineM-Cy-labeled hMSCs and chondrocytes showed a positive signal effect on T1-weighted images and a negative signal effect on T2-weighted images while Ferucarbotran-labeled cells provided a negative signal effect on all sequences. CNR data for both GadofluorineM-Cy-labeled and Ferucarbotran-labeled hMSCs were significantly different compared to unlabeled control cells on T1-weighted SE and T2*-weighted MR images (p<0.017. CONCLUSION: hMSCs can be labeled by simple incubation with GadofluorineM-Cy. The labeled cells provide significant MR signal effects and less impaired chondrogenesis compared to Ferucarbotran-labeled h

  15. The BRAIN Initiative Provides a Unifying Context for Integrating Core STEM Competencies into a Neurobiology Course.

    Science.gov (United States)

    Schaefer, Jennifer E

    2016-01-01

    The Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative introduced by the Obama Administration in 2013 presents a context for integrating many STEM competencies into undergraduate neuroscience coursework. The BRAIN Initiative core principles overlap with core STEM competencies identified by the AAAS Vision and Change report and other entities. This neurobiology course utilizes the BRAIN Initiative to serve as the unifying theme that facilitates a primary emphasis on student competencies such as scientific process, scientific communication, and societal relevance while teaching foundational neurobiological content such as brain anatomy, cellular neurophysiology, and activity modulation. Student feedback indicates that the BRAIN Initiative is an engaging and instructional context for this course. Course module organization, suitable BRAIN Initiative commentary literature, sample primary literature, and important assignments are presented.

  16. Stab injury and device implantation within the brain results in inversely multiphasic neuroinflammatory and neurodegenerative responses

    Science.gov (United States)

    Potter, Kelsey A.; Buck, Amy C.; Self, Wade K.; Capadona, Jeffrey R.

    2012-08-01

    An estimated 25 million people in the US alone rely on implanted medical devices, ˜2.5 million implanted within the nervous system. Even though many devices perform adequately for years, the host response to medical devices often severely limits tissue integration and long-term performance. This host response is believed to be particularly limiting in the case of intracortical microelectrodes, where it has been shown that glial cell encapsulation and localized neuronal cell loss accompany intracortical microelectrode implantation. Since neuronal ensembles must be within ˜50 µm of the electrode to obtain neuronal spikes and local field potentials, developing a better understanding of the molecular and cellular environment at the device-tissue interface has been the subject of significant research. Unfortunately, immunohistochemical studies of scar maturation in correlation to device function have been inconclusive. Therefore, here we present a detailed quantitative study of the cellular events and the stability of the blood-brain barrier (BBB) following intracortical microelectrode implantation and cortical stab injury in a chronic survival model. We found two distinctly inverse multiphasic profiles for neuronal survival in device-implanted tissue compared to stab-injured animals. For chronically implanted animals, we observed a biphasic paradigm between blood-derived/trauma-induced and CNS-derived inflammatory markers driving neurodegeneration at the interface. In contrast, stab injured animals demonstrated a CNS-mediated neurodegenerative environment. Collectively these data provide valuable insight to the possibility of multiple roles of chronic neuroinflammatory events on BBB disruption and localized neurodegeneration, while also suggesting the importance to consider multiphasic neuroinflammatory kinetics in the design of therapeutic strategies for stabilizing neural interfaces.

  17. Are human dental papilla-derived stem cell and human brain-derived neural stem cell transplantations suitable for treatment of Parkinson's disease?

    Institute of Scientific and Technical Information of China (English)

    Hyung Ho Yoon; Joongkee Min; Nari Shin; Yong Hwan Kim; Jin-Mo Kim; Yu-Shik Hwang; Jun-Kyo Francis Suh; Onyou Hwang; Sang Ryong Jeon

    2013-01-01

    Transplantation of neural stem cells has been reported as a possible approach for replacing impaired dopaminergic neurons. In this study, we tested the efficacy of early-stage human dental papilla-derived stem cells and human brain-derived neural stem cells in rat models of 6-hydroxydopamine-induced Parkinson's disease. Rats received a unilateral injection of 6-hydroxydopamine into right medial forebrain bundle, followed 3 weeks later by injections of PBS, early-stage human dental papilla-derived stem cells, or human brain-derived neural stem cells into the ipsilateral striatum. All of the rats in the human dental papilla-derived stem cell group died from tumor formation at around 2 weeks following cell transplantation. Postmortem examinations revealed homogeneous malignant tumors in the striatum of the human dental papilla-derived stem cell group. Stepping tests revealed that human brain-derived neural stem cell transplantation did not improve motor dysfunction. In apomorphine-induced rotation tests, neither the human brain-derived neural stem cell group nor the control groups (PBS injection) demonstrated significant changes. Glucose metabolism in the lesioned side of striatum was reduced by human brain-derived neural stem cell transplantation. [18 F]-FP-CIT PET scans in the striatum did not demonstrate a significant increase in the human brain-derived neural stem cell group. Tyrosine hydroxylase (dopaminergic neuronal marker) staining and G protein-activated inward rectifier potassium channel 2 (A9 dopaminergic neuronal marker) were positive in the lesioned side of striatum in the human brain-derived neural stem cell group. The use of early-stage human dental papilla-derived stem cells confirmed its tendency to form tumors. Human brain-derived neural stem cells could be partially differentiated into dopaminergic neurons, but they did not secrete dopamine.

  18. Isolation, cultivation and identification of brain glioma stem cells by magnetic bead sorting

    Institute of Scientific and Technical Information of China (English)

    Xiuping Zhou; Chao Zheng; Qiong Shi; Xiang Li; Zhigang Shen; Rutong Yu

    2012-01-01

    This study describes a detailed process for obtaining brain glioma stem cells from freshly dissected human brain glioma samples using an immunomagnetic bead technique combined with serum-free media pressure screening. Furthermore, the proliferation, differentiation and self-renewal biological features of brain glioma stem cells were identified. Results showed that a small number of CD133 positive tumor cells isolated from brain glioma samples survived as a cell suspension in serum-free media and proliferated. Subcultured CD133 positive cells maintained a potent self-renewal and proliferative ability, and expressed the stem cell-specific markers CD133 and nestin. After incubation with fetal bovine serum, the number of glial fibrillary acidic protein and microtubule associated protein 2 positive cells increased significantly, indicating that the cultured brain glioma stem cells can differentiate into astrocytes and neurons. Western blot analysis showed that tumor suppressor phosphatase and tensin homolog was highly expressed in tumor spheres compared with the differentiated tumor cells. These experimental findings indicate that the immunomagnetic beads technique is a useful method to obtain brain glioma stem cells from human brain tumors.

  19. Brain dynamics that correlate with effects of learning on auditory distance perception.

    Science.gov (United States)

    Wisniewski, Matthew G; Mercado, Eduardo; Church, Barbara A; Gramann, Klaus; Makeig, Scott

    2014-01-01

    Accuracy in auditory distance perception can improve with practice and varies for sounds differing in familiarity. Here, listeners were trained to judge the distances of English, Bengali, and backwards speech sources pre-recorded at near (2-m) and far (30-m) distances. Listeners' accuracy was tested before and after training. Improvements from pre-test to post-test were greater for forward speech, demonstrating a learning advantage for forward speech sounds. Independent component (IC) processes identified in electroencephalographic (EEG) data collected during pre- and post-testing revealed three clusters of ICs across subjects with stimulus-locked spectral perturbations related to learning and accuracy. One cluster exhibited a transient stimulus-locked increase in 4-8 Hz power (theta event-related synchronization; ERS) that was smaller after training and largest for backwards speech. For a left temporal cluster, 8-12 Hz decreases in power (alpha event-related desynchronization; ERD) were greatest for English speech and less prominent after training. In contrast, a cluster of IC processes centered at or near anterior portions of the medial frontal cortex showed learning-related enhancement of sustained increases in 10-16 Hz power (upper-alpha/low-beta ERS). The degree of this enhancement was positively correlated with the degree of behavioral improvements. Results suggest that neural dynamics in non-auditory cortical areas support distance judgments. Further, frontal cortical networks associated with attentional and/or working memory processes appear to play a role in perceptual learning for source distance.

  20. Amplification of neural stem cell proliferation by intermediate progenitor cells in Drosophila brain development

    Directory of Open Access Journals (Sweden)

    Bello Bruno C

    2008-02-01

    Full Text Available Abstract Background In the mammalian brain, neural stem cells divide asymmetrically and often amplify the number of progeny they generate via symmetrically dividing intermediate progenitors. Here we investigate whether specific neural stem cell-like neuroblasts in the brain of Drosophila might also amplify neuronal proliferation by generating symmetrically dividing intermediate progenitors. Results Cell lineage-tracing and genetic marker analysis show that remarkably large neuroblast lineages exist in the dorsomedial larval brain of Drosophila. These lineages are generated by brain neuroblasts that divide asymmetrically to self renew but, unlike other brain neuroblasts, do not segregate the differentiating cell fate determinant Prospero to their smaller daughter cells. These daughter cells continue to express neuroblast-specific molecular markers and divide repeatedly to produce neural progeny, demonstrating that they are proliferating intermediate progenitors. The proliferative divisions of these intermediate progenitors have novel cellular and molecular features; they are morphologically symmetrical, but molecularly asymmetrical in that key differentiating cell fate determinants are segregated into only one of the two daughter cells. Conclusion Our findings provide cellular and molecular evidence for a new mode of neurogenesis in the larval brain of Drosophila that involves the amplification of neuroblast proliferation through intermediate progenitors. This type of neurogenesis bears remarkable similarities to neurogenesis in the mammalian brain, where neural stem cells as primary progenitors amplify the number of progeny they generate through generation of secondary progenitors. This suggests that key aspects of neural stem cell biology might be conserved in brain development of insects and mammals.

  1. Stereotactic iodine-125 brachytherapy for brain tumors: temporary versus permanent implantation

    Directory of Open Access Journals (Sweden)

    Ruge Maximilian I

    2012-06-01

    Full Text Available Abstract Stereotactic brachytherapy (SBT has been described in several publications as an effective, minimal invasive and safe highly focal treatment option in selected patients with well circumscribed brain tumors 40 cGy/h in combination with adjuvant external beam radiation and/or chemotherapy for the treatment of malignant gliomas and metastases resulted in increased rates of radiation induced adverse tissue changes requiring surgical intervention. Vice versa, such effects have been only minimally observed in numerous studies applying low dose rate (LDR regiments (3–8 cGy/h for low grade gliomas, metastases and other rare indications. Besides these observations, there are, however, no data available directly comparing the long term incidences of tissue changes after HDR and LDR and there is, furthermore, no evidence regarding a difference between temporary or permanent LDR implantation schemes. Thus, recommendations for effective and safe implantation schemes have to be investigated and compared in future studies.

  2. An implantable VLSI architecture for real time spike sorting in cortically controlled Brain Machine Interfaces.

    Science.gov (United States)

    Aghagolzadeh, Mehdi; Zhang, Fei; Oweiss, Karim

    2010-01-01

    Brain Machine Interface (BMI) systems demand real-time spike sorting to instantaneously decode the spike trains of simultaneously recorded cortical neurons. Real-time spike sorting, however, requires extensive computational power that is not feasible to implement in implantable BMI architectures, thereby requiring transmission of high-bandwidth raw neural data to an external computer. In this work, we describe a miniaturized, low power, programmable hardware module capable of performing this task within the resource constraints of an implantable chip. The module computes a sparse representation of the spike waveforms followed by "smart" thresholding. This cascade restricts the sparse representation to a subset of projections that preserve the discriminative features of neuron-specific spike waveforms. In addition, it further reduces telemetry bandwidth making it feasible to wirelessly transmit only the important biological information to the outside world, thereby improving the efficiency, practicality and viability of BMI systems in clinical applications.

  3. Stem cells modified by brain-derived neurotrophic fac-tor to promote stem cells differentiation into neurons and enhance neuromotor function after brain injury

    Institute of Scientific and Technical Information of China (English)

    ZHANG Sai; LIU Xiao-zhi; LIU Zhen-lin; WANG Yan-min; HU Qun-liang; MA Tie-zhu; SUN Shi-zhong

    2009-01-01

    Objective: To promote stem cells differentiation into neurons and enhance neuromotor function after brain in-jury through brain-derived neurotrophic factor (BDNF) induction.Methods: Recombinant adenovirus vector was ap-plied to the transfection of BDNF into human-derived um-bilical cord mesenchymal stem cells (UCMSCs). Enzyme linked immunosorbent assay (ELISA) was used to deter-mine the secretion phase of BDNF. The brain injury model of athymic mice induced by hydraulic pressure percussion was established for transplantation of stem cells into the edge of injury site. Nerve function scores were obtained, and the expression level of transfected and non-transfected BDNF, proportion of neuron specific enolase (NSE) andglial fibrillary acidic protein (GFAP), and the number of apoptosis cells were compared respectively. Results: The BDNF expression achieved its stabiliza-tion at a high level 72 hours after gene transfection. The mouse obtained a better score of nerve function, and the proportion of the NSE-positive cells increased significantly (P<0.05), but GFAP-positive cells decreased in BDNF-UCMSCs group compared with the other two groups (P<0.05). At the site of high expression of BDNF, the number of apoptosis cells decreased markedly.Conclusion: BDNF gene can promote the differentia-tion of the stem cells into neurons rather than gliai cells, and enhance neuromotor function after brain injury.

  4. Prospects and Limitations of Using Endogenous Neural Stem Cells for Brain Regeneration

    Directory of Open Access Journals (Sweden)

    Kazunobu Sawamoto

    2011-01-01

    Full Text Available Neural stem cells (NSCs are capable of producing a variety of neural cell types, and are indispensable for the development of the mammalian brain. NSCs can be induced in vitro from pluripotent stem cells, including embryonic stem cells and induced-pluripotent stem cells. Although the transplantation of these exogenous NSCs is a potential strategy for improving presently untreatable neurological conditions, there are several obstacles to its implementation, including tumorigenic, immunological, and ethical problems. Recent studies have revealed that NSCs also reside in the adult brain. The endogenous NSCs are activated in response to disease or trauma, and produce new neurons and glia, suggesting they have the potential to regenerate damaged brain tissue while avoiding the above-mentioned problems. Here we present an overview of the possibility and limitations of using endogenous NSCs in regenerative medicine.

  5. Prospects and limitations of using endogenous neural stem cells for brain regeneration.

    Science.gov (United States)

    Kaneko, Naoko; Kako, Eisuke; Sawamoto, Kazunobu

    2011-01-14

    Neural stem cells (NSCs) are capable of producing a variety of neural cell types, and are indispensable for the development of the mammalian brain. NSCs can be induced in vitro from pluripotent stem cells, including embryonic stem cells and induced-pluripotent stem cells. Although the transplantation of these exogenous NSCs is a potential strategy for improving presently untreatable neurological conditions, there are several obstacles to its implementation, including tumorigenic, immunological, and ethical problems. Recent studies have revealed that NSCs also reside in the adult brain. The endogenous NSCs are activated in response to disease or trauma, and produce new neurons and glia, suggesting they have the potential to regenerate damaged brain tissue while avoiding the above-mentioned problems. Here we present an overview of the possibility and limitations of using endogenous NSCs in regenerative medicine.

  6. Dosimetric response of radioactive bio glass seeds implants on rabbit brain; Resposta radiodosimetrica de implantes de sementes de biovidros radioativos no cerebro de coelhos

    Energy Technology Data Exchange (ETDEWEB)

    Costa, I.T.; Campos, T.P.R., E-mail: itemponi@yahoo.com.br, E-mail: campos@nuclear.ufmg.br [Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares - Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil)

    2007-07-01

    Interstitial implants of radioactive seeds are used as an efficient way of treating brain tumors. Bio glasses is an interesting alternative to the metallic implanted materials, because they can be absorbed by the organism, reducing the possibilities of side effects. The present paper investigates the dosimetry by the implants performed on rabbit's brain on the NRI/UFMG research group. The spatial distribution of the specific ionizing energy deposited per unit of mass generated by Sm-153 seeds were evaluated. A computational model of the brain's region was built using the software SISCODES produced by the research group. The sections of the computer tomography of a rabbit, which was included on the experiment, were digitalized. Those were converted in a three dimensional voxel model, including the tissues, its chemical composition and density. A simulation of the particles transport is performed by the stochastic code MCNP5. The implants consist of 15 ceramic Ca-Si-Sm seeds enriched with Sm-153, with 1.1.6 mm of length and 0.3 mm diameter, implanted on the rabbit's brain. It was predicted on the model three ribbons of 5 seeds each, spaced by 1.1.2 mm, since the ribbons were in a triangular topology whose vertices were spaced by 8 mm. The activities were 120 MBq/seed. The results show isodose regions superposed over the rabbits' model, reproducing the spatial energy deposition on the brain region. The absorbed dose predicted was 3.2 Gy per 15 seed; however it was not enough to tumor control. The authors suggest to increase the number of seeds and activity, reduction of the space to 5-6 mm among ribbons, improving dose with the beta emitting. (author)

  7. Computational modeling of chemotactic signaling and aggregation of microglia around implantation site during deep brain stimulation

    Science.gov (United States)

    Silchenko, A. N.; Tass, P. A.

    2013-10-01

    It is well established that prolonged electrical stimulation of brain tissue causes massive release of ATP in the extracellular space. The released ATP and the products of its hydrolysis, such as ADP and adenosine, become the main elements mediating chemotactic sensitivity and motility of microglial cells via subsequent activation of P2Y2,12 as well as A3A and A2A adenosine receptors. The size of the sheath around the electrode formed by the microglial cells is an important criterion for the optimization of the parameters of electrical current delivered to brain tissue. Here, we study a purinergic signaling pathway underlying the chemotactic motion of microglia towards the implanted electrode during deep brain stimulation. We present a computational model describing formation of a stable aggregate around the implantation site due to the joint chemo-attractive action of ATP and ADP together with a mixed influence of extracellular adenosine. The model was built in accordance with the classical Keller-Segel approach and includes an equation for the cells' density as well as equations describing the hydrolysis of extracellular ATP via successive reaction steps ATP →ADP →AMP →adenosine. The results of our modeling allowed us to reveal the dependence of the width of the encapsulating layer around the electrode on the amount of ATP released due to permanent electrical stimulation. The dependences of the aggregates' size on the parameter governing the nonlinearity of interaction between extracellular adenosine and adenosine receptors are also analyzed.

  8. Visual task complexity modulates the brain's response to unattended auditory novelty.

    Science.gov (United States)

    Yucel, Gunes; Petty, Christopher; McCarthy, Gregory; Belger, Aysenil

    2005-07-13

    New, unusual, and changing events are important environmental cues, and the ability to detect these types of stimuli in the environment constitutes a biologically significant survival skill. We used event-related potentials to examine whether sensory and cognitive neural responses to unattended novel events are modulated by the complexity of a primary visuomotor task. Event-related potentials were elicited by unattended task-irrelevant pitch-deviant tones and novel environmental sounds while study participants performed a continuous visuomotor tracking task at two levels of difficulty, achieved by manipulating the control dynamics of a joystick. The results revealed that increased task complexity modulated evoked sensory and cognitive event-related potential components, indicating that detection of change and novelty in the unattended auditory channel is resource-limited.

  9. Applying peripheral auditory model to improve CIS strategy for cochlear implant%采用听觉外周模型改进电子耳蜗CIS方案

    Institute of Scientific and Technical Information of China (English)

    孙文业; 陶智; 孙宝印; 倪赛华; 王振明; 顾济华

    2014-01-01

    提出了一种改进的CIS电子耳蜗的脉冲刺激方案。利用听觉外周模型产生一种符合听神经发放机制的刺激脉冲序列来刺激电极,代替传统的均匀交替刺激方案,不仅可以通过包络而且可以通过脉冲间隔来传递语音信息,确保了语音的空间编码和时间编码。听觉仿真实验表明,相对于其他两种方案,方案可以有效地传递更多更丰富的语音信息,在汉语声调识别实验中至少提高19.2%识别率,在可懂度的对比实验中具有最高可懂度。%A stimulation strategy for cochlear implant is proposed. The proposed strategy applies the stochastic firing characteristic of peripheral auditory nerve to generate the impulse train stimulating the corresponding electrode, instead of traditional uniform alternating stimulating strategy. Therefore, speech information can be conveyed not only by the envelope but also impulse intervals by the proposed strategy, which ensure both the space principle and time principle. Auditory simulation experiments show that the proposed strategy can efficiently convey more speech information when comparing with the other strategies. The proposed strategy improves the recognition rate at least 19.2% at the Chinese tone recogni-tion experiment, and has the highest intelligibility at the intelligibility contrast experiment.

  10. Origins and clinical implications of the brain tumor stem cell hypothesis

    OpenAIRE

    2009-01-01

    With the advent of the cancer stem cell hypothesis, the field of cancer research has experienced a revolution in how we think of and approach cancer. The discovery of “brain tumor stem cells” has offered an explanation for several long-standing conundrums on why brain tumors behave the way they do to treatment. Despite the great amount of research that has been done in order to understand the molecular aspects of malignant gliomas, the prognosis of brain tumors remains dismal. The slow progre...

  11. Analysis of Neural Stem Cells from Human Cortical Brain Structures In Vitro.

    Science.gov (United States)

    Aleksandrova, M A; Poltavtseva, R A; Marei, M V; Sukhikh, G T

    2016-05-01

    Comparative immunohistochemical analysis of the neocortex from human fetuses showed that neural stem and progenitor cells are present in the brain throughout the gestation period, at least from week 8 through 26. At the same time, neural stem cells from the first and second trimester fetuses differed by the distribution, morphology, growth, and quantity. Immunocytochemical analysis of neural stem cells derived from fetuses at different gestation terms and cultured under different conditions showed their differentiation capacity. Detailed analysis of neural stem cell populations derived from fetuses on gestation weeks 8-9, 18-20, and 26 expressing Lex/SSEA1 was performed.

  12. Brain dynamics that correlate with effects of learning on auditory distance perception

    Directory of Open Access Journals (Sweden)

    Matthew G. Wisniewski

    2014-12-01

    Full Text Available Accuracy in auditory distance perception can improve with practice and varies for sounds differing in familiarity. Here, listeners were trained to judge the distances of English, Bengali, and backwards speech sources pre-recorded at near (2-m and far (30-m distances. Listeners’ accuracy was tested before and after training. Improvements from pre-test to post-test were greater for forward speech, demonstrating a learning advantage for forward speech sounds. Independent component (IC processes identified in electroencephalographic (EEG data collected during pre- and post-testing revealed three clusters of ICs across subjects with stimulus-locked spectral perturbations related to learning and accuracy. One cluster exhibited a transient stimulus-locked increase in 4-8 Hz power (theta event-related synchronization; ERS that was smaller after training and largest for backwards speech. For a left temporal cluster, 8-12 Hz decreases in power (alpha event-related desynchronization; ERD were greatest for English speech and less prominent after training. In contrast, a cluster of IC processes centered at or near anterior portions of the medial frontal cortex showed learning-related enhancement of sustained increases in 10-16 Hz power (upper-alpha/low-beta ERS. The degree of this enhancement was positively correlated with the degree of behavioral improvements. Results suggest that neural dynamics in non-auditory cortical areas support distance judgments. Further, frontal cortical networks associated with attentional and/or working memory processes appear to play a role in perceptual learning for source distance.

  13. A Novel Biopsy Method for Isolating Neural Stem Cells from the Subventricular Zone of the Adult Rat Brain for Autologous Transplantation in CNS Injuries.

    Science.gov (United States)

    Aligholi, Hadi; Hassanzadeh, Gholamreza; Gorji, Ali; Azari, Hassan

    2016-01-01

    Despite all attempts the problem of regeneration in damaged central nervous system (CNS) has remained challenging due to its cellular complexity and highly organized and sophisticated connections. In this regard, stem cell therapy might serve as a viable therapeutic approach aiming either to support the damaged tissue and hence to reduce the subsequent neurological dysfunctions and impairments or to replace the lost cells and re-establish damaged circuitries. Adult neural stem/progenitor cells (NS/PCs) are one of the outstanding cell sources that can be isolated from the subventricular zone (SVZ) of the lateral ventricles. These cells can differentiate into neurons, astrocytes, and oligodendrocytes. Implanting autologous NS/PCs will greatly benefit the patients by avoiding immune rejection after implantation, better survival, and integration with the host tissue. Developing safe and efficient methods in small animal models will provide us with the opportunity to optimize procedures required to achieve successful human autologous NS/PC transplantation in near future. In this chapter, a highly controlled and safe biopsy method for harvesting stem cell containing tissue from the SVZ of adult rat brain is introduced. Then, isolation and expansion of NS/PCs from harvested specimen as well as the techniques to verify proliferation and differentiation capacity of the resulting NS/PCs are discussed. Finally, a method for assessing the biopsy lesion volume in the brain is described. This safe biopsy method in rat provides a unique tool to study autologous NS/PC transplantation in different CNS injury models.

  14. Expression of c-jun in brain stem following moderate lateral fluid percussion brain injury in rats

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    AIM: To study the expression of c-jun in brain stem following moderate lateral fluid percussion brain injury in rats, and to observe the temporal patterns of its expressions following percussion.METHODS: Male Sprague-Dawley rats were divided into normal control, sham operation control and injury groups. The rats of injury group subjected to moderate lateral fluid percussion injury (0.2 mPa), and then were subdivided into 5 min, 15 min, 30 min, 1 h, 2 h, 4 h, 8 h and 12 h groups according to the time elapsed after injury. The expression of c-jun was studied by immunohistochemistry and in situ hybridization. RESULTS: After percussion for 15 min, Jun positive neurons increased in brain stem progressively, and peaked at 12h. At 5min after percussion, the induction of c-jun mRNA was increased, and remained elevated up to 1h-2h after brain injury. CONCLUSION: The induction and expression of the c-jun in brain stem after fluid percussion brain injury were increased rapidly and lasted for a long time.

  15. PPG neurons of the lower brain stem and their role in brain GLP-1 receptor activation.

    Science.gov (United States)

    Trapp, Stefan; Cork, Simon C

    2015-10-15

    Within the brain, glucagon-like peptide-1 (GLP-1) affects central autonomic neurons, including those controlling the cardiovascular system, thermogenesis, and energy balance. Additionally, GLP-1 influences the mesolimbic reward system to modulate the rewarding properties of palatable food. GLP-1 is produced in the gut and by hindbrain preproglucagon (PPG) neurons, located mainly in the nucleus tractus solitarii (NTS) and medullary intermediate reticular nucleus. Transgenic mice expressing glucagon promoter-driven yellow fluorescent protein revealed that PPG neurons not only project to central autonomic control regions and mesolimbic reward centers, but also strongly innervate spinal autonomic neurons. Therefore, these brain stem PPG neurons could directly modulate sympathetic outflow through their spinal inputs to sympathetic preganglionic neurons. Electrical recordings from PPG neurons in vitro have revealed that they receive synaptic inputs from vagal afferents entering via the solitary tract. Vagal afferents convey satiation to the brain from signals like postprandial gastric distention or activation of peripheral GLP-1 receptors. CCK and leptin, short- and long-term satiety peptides, respectively, increased the electrical activity of PPG neurons, while ghrelin, an orexigenic peptide, had no effect. These findings indicate that satiation is a main driver of PPG neuronal activation. They also show that PPG neurons are in a prime position to respond to both immediate and long-term indicators of energy and feeding status, enabling regulation of both energy balance and general autonomic homeostasis. This review discusses the question of whether PPG neurons, rather than gut-derived GLP-1, are providing the physiological substrate for the effects elicited by central nervous system GLP-1 receptor activation.

  16. Mesenchymal stem cell implantation in atrophic nonunion of the long bones

    Science.gov (United States)

    Phedy, P.; Kholinne, E.; Djaja, Y. P.; Kusnadi, Y.; Merlina, M.; Yulisa, N. D.

    2016-01-01

    Objectives To explore the therapeutic potential of combining bone marrow-derived mesenchymal stem cells (BM-MSCs) and hydroxyapatite (HA) granules to treat nonunion of the long bone. Methods Ten patients with an atrophic nonunion of a long bone fracture were selectively divided into two groups. Five subjects in the treatment group were treated with the combination of 15 million autologous BM-MSCs, 5g/cm3 (HA) granules and internal fixation. Control subjects were treated with iliac crest autograft, 5g/cm3 HA granules and internal fixation. The outcomes measured were post-operative pain (visual analogue scale), level of functionality (LEFS and DASH), and radiograph assessment. Results Post-operative pain evaluation showed no significant differences between the two groups. The treatment group demonstrated faster initial radiographic and functional improvements. Statistically significant differences in functional scores were present during the first (p = 0.002), second (p = 0.005) and third (p = 0.01) month. Both groups achieved similar outcomes by the end of one-year follow-up. No immunologic or neoplastic side effects were reported. Conclusions All cases of nonunion of a long bone presented in this study were successfully treated using autologous BM-MSCs. The combination of autologous BM-MSCs and HA granules is a safe method for treating nonunion. Patients treated with BM-MSCs had faster initial radiographic and functional improvements. By the end of 12 months, both groups had similar outcomes. Cite this article: H.D. Ismail, P. Phedy, E. Kholinne, Y. P. Djaja, Y. Kusnadi, M. Merlina, N. D. Yulisa. Mesenchymal stem cell implantation in atrophic nonunion of the long bones: A translational study. Bone Joint Res 2016;5:287–293. DOI: 10.1302/2046-3758.57.2000587. PMID:27412657

  17. The preventive effects of neural stem cells and mesenchymal stem cells intra-ventricular injection on brain stroke in rats

    Directory of Open Access Journals (Sweden)

    Seyed Mojtaba Hosseini

    2015-01-01

    Full Text Available Introduction: Stroke is one of the most important causes of disability in developed countries and, unfortunately, there is no effective treatment for this major problem of central nervous system (CNS; cell therapy may be helpful to recover this disease. In some conditions such as cardiac surgeries and neurosurgeries, there are some possibilities of happening brain stroke. Inflammation of CNS plays an important role in stroke pathogenesis, in addition, apoptosis and neural death could be the other reasons of poor neurological out come after stroke. In this study, we examined the preventive effects of the neural stem cells (NSCs and mesenchymal stem cells (MSCs intra-ventricular injected on stroke in rats. Aim: The aim of this study was to investigate the preventive effects of neural and MSCs for stroke in rats. Materials and Methods: The MSCs were isolated by flashing the femurs and tibias of the male rats with appropriate media. The NSCs were isolated from rat embryo ganglion eminence and they cultured NSCs media till the neurospheres formed. Both NSCs and MSCs were labeled with PKH26-GL. One day before stroke, the cells were injected into lateral ventricle stereotactically. Results: During following for 28 days, the neurological scores indicated that there are better recoveries in the groups received stem cells and they had less lesion volume in their brain measured by hematoxylin and eosin staining. Furthermore, the activities of caspase-3 were lower in the stem cell received groups than control group and the florescent microscopy images showed that the stem cells migrated to various zones of the brains. Conclusion: Both NSCs and MSCs are capable of protecting the CNS against ischemia and they may be good ways to prevent brain stroke consequences situations.

  18. External fixation of femoral defects in athymic rats: Applications for human stem cell implantation and bone regeneration

    Directory of Open Access Journals (Sweden)

    Terasa Foo

    2013-01-01

    Full Text Available An appropriate animal model is critical for the research of stem/progenitor cell therapy and tissue engineering for bone regeneration in vivo. This study reports the design of an external fixator and its application to critical-sized femoral defects in athymic rats. The external fixator consists of clamps and screws that are readily available from hardware stores as well as Kirschner wires. A total of 35 rats underwent application of the external fixator with creation of a 6-mm bone defect in one femur of each animal. This model had been used in several separate studies, including implantation of collagen gel, umbilical cord blood mesenchymal stem cells, endothelial progenitor cells, or bone morphogenetic protein-2. One rat developed fracture at the proximal pin site and two rats developed deep tissue infection. Pin loosening was found in nine rats, but it only led to the failure of external fixation in two animals. In 8 to 10 weeks, various degrees of bone growth in the femoral defects were observed in different study groups, from full repair of the bone defect with bone morphogenetic protein-2 implantation to fibrous nonunion with collagen gel implantation. The external fixator used in these studies provided sufficient mechanical stability to the bone defects and had a comparable complication rate in athymic rats as in immunocompetent rats. The external fixator does not interfere with the natural environment of a bone defect. This model is particularly valuable for investigation of osteogenesis of human stem/progenitor cells in vivo.

  19. Stem cell therapy for neonatal brain injury : Perspectives and Challenges

    NARCIS (Netherlands)

    Titomanlio, Luigi; Kavelaars, Annemieke; Dalous, Jeremie; Mani, Shyamala; El Ghouzzi, Vincent; Heijnen, Cobi; Baud, Olivier; Gressens, Pierre

    2011-01-01

    Cerebral palsy is a major health problem caused by brain damage during pregnancy, delivery, or the immediate postnatal period. Perinatal stroke, intraventricular hemorrhage, and asphyxia are the most common causes of neonatal brain damage. Periventricular white matter damage (periventricular leukoma

  20. A power-efficient communication system between brain-implantable devices and external computers.

    Science.gov (United States)

    Yao, Ning; Lee, Heung-No; Chang, Cheng-Chun; Sclabassi, Robert J; Sun, Mingui

    2007-01-01

    In this paper, we propose a power efficient communication system for linking a brain-implantable device to an external system. For battery powered implantable devices, the processor and the transmitter power should be reduced in order to both conserve battery power and reduce the health risks associated with transmission. To accomplish this, a joint source-channel coding/decoding system is devised. Low-density generator matrix (LDGM) codes are used in our system due to their low encoding complexity. The power cost for signal processing within the implantable device is greatly reduced by avoiding explicit source encoding. Raw data which is highly correlated is transmitted. At the receiver, a Markov chain source correlation model is utilized to approximate and capture the correlation of raw data. A turbo iterative receiver algorithm is designed which connects the Markov chain source model to the LDGM decoder in a turbo-iterative way. Simulation results show that the proposed system can save up to 1 to 2.5 dB on transmission power.

  1. Brain activity is related to individual differences in the number of items stored in auditory short-term memory for pitch: evidence from magnetoencephalography.

    Science.gov (United States)

    Grimault, Stephan; Nolden, Sophie; Lefebvre, Christine; Vachon, François; Hyde, Krista; Peretz, Isabelle; Zatorre, Robert; Robitaille, Nicolas; Jolicoeur, Pierre

    2014-07-01

    We used magnetoencephalography (MEG) to examine brain activity related to the maintenance of non-verbal pitch information in auditory short-term memory (ASTM). We focused on brain activity that increased with the number of items effectively held in memory by the participants during the retention interval of an auditory memory task. We used very simple acoustic materials (i.e., pure tones that varied in pitch) that minimized activation from non-ASTM related systems. MEG revealed neural activity in frontal, temporal, and parietal cortices that increased with a greater number of items effectively held in memory by the participants during the maintenance of pitch representations in ASTM. The present results reinforce the functional role of frontal and temporal cortices in the retention of pitch information in ASTM. This is the first MEG study to provide both fine spatial localization and temporal resolution on the neural mechanisms of non-verbal ASTM for pitch in relation to individual differences in the capacity of ASTM. This research contributes to a comprehensive understanding of the mechanisms mediating the representation and maintenance of basic non-verbal auditory features in the human brain.

  2. Developmental and cross-modal plasticity in deafness: evidence from the P1 and N1 event related potentials in cochlear implanted children.

    Science.gov (United States)

    Sharma, Anu; Campbell, Julia; Cardon, Garrett

    2015-02-01

    Cortical development is dependent on extrinsic stimulation. As such, sensory deprivation, as in congenital deafness, can dramatically alter functional connectivity and growth in the auditory system. Cochlear implants ameliorate deprivation-induced delays in maturation by directly stimulating the central nervous system, and thereby restoring auditory input. The scenario in which hearing is lost due to deafness and then reestablished via a cochlear implant provides a window into the development of the central auditory system. Converging evidence from electrophysiologic and brain imaging studies of deaf animals and children fitted with cochlear implants has allowed us to elucidate the details of the time course for auditory cortical maturation under conditions of deprivation. Here, we review how the P1 cortical auditory evoked potential (CAEP) provides useful insight into sensitive period cut-offs for development of the primary auditory cortex in deaf children fitted with cochlear implants. Additionally, we present new data on similar sensitive period dynamics in higher-order auditory cortices, as measured by the N1 CAEP in cochlear implant recipients. Furthermore, cortical re-organization, secondary to sensory deprivation, may take the form of compensatory cross-modal plasticity. We provide new case-study evidence that cross-modal re-organization, in which intact sensory modalities (i.e., vision and somatosensation) recruit cortical regions associated with deficient sensory modalities (i.e., auditory) in cochlear implanted children may influence their behavioral outcomes with the implant. Improvements in our understanding of developmental neuroplasticity in the auditory system should lead to harnessing central auditory plasticity for superior clinical technique.

  3. Auditory Hallucinations and the Brain's Resting-State Networks : Findings and Methodological Observations

    NARCIS (Netherlands)

    Alderson-Day, Ben; Diederen, Kelly; Fernyhough, Charles; Ford, Judith M; Horga, Guillermo; Margulies, Daniel S; McCarthy-Jones, Simon; Northoff, Georg; Shine, James M; Turner, Jessica; van de Ven, Vincent; van Lutterveld, Remko; Waters, Flavie; Jardri, Renaud

    2016-01-01

    In recent years, there has been increasing interest in the potential for alterations to the brain's resting-state networks (RSNs) to explain various kinds of psychopathology. RSNs provide an intriguing new explanatory framework for hallucinations, which can occur in different modalities and populati

  4. Age-Related Changes in Transient and Oscillatory Brain Responses to Auditory Stimulation during Early Adolescence

    Science.gov (United States)

    Poulsen, Catherine; Picton, Terence W.; Paus, Tomas

    2009-01-01

    Maturational changes in the capacity to process quickly the temporal envelope of sound have been linked to language abilities in typically developing individuals. As part of a longitudinal study of brain maturation and cognitive development during adolescence, we employed dense-array EEG and spatiotemporal source analysis to characterize…

  5. [Stem Cells in the Brain of Mammals and Human: Fundamental and Applied Aspects].

    Science.gov (United States)

    Aleksandrova, M A; Marey, M V

    2015-01-01

    Brain stem cells represent an extremely intriguing phenomenon. The aim of our review is to present an integrity vision of their role in the brain of mammals and humans, and their clinical perspectives. Over last two decades, investigations of biology of the neural stem cells produced significant changes in general knowledge about the processes of development and functioning of the brain. Researches on the cellular and molecular mechanisms of NSC differentiation and behavior led to new understanding of their involvement in learning and memory. In the regenerative medicine, original therapeutic approaches to neurodegenerative brain diseases have been elaborated due to fundamental achievements in this field. They are based on specific regenerative potential of neural stem cells and progenitor cells, which possess the ability to replace dead cells and express crucially significant biologically active factors that are missing in the pathological brain. For the needs of cell substitution therapy in the neural diseases, adequate methods of maintaining stem cells in culture and their differentiation into different types of neurons and glial cells, have been developed currently. The success of modern cellular technologies has significantly expanded the range of cells used for cell therapy. The near future may bring new perspective and distinct progress in brain cell therapy due to optimizing the cells types most promising for medical needs.

  6. Sumoylation of hypoxia-inducible factor-1α ameliorates failure of brain stem cardiovascular regulation in experimental brain death.

    Directory of Open Access Journals (Sweden)

    Julie Y H Chan

    Full Text Available BACKGROUND: One aspect of brain death is cardiovascular deregulation because asystole invariably occurs shortly after its diagnosis. A suitable neural substrate for mechanistic delineation of this aspect of brain death resides in the rostral ventrolateral medulla (RVLM. RVLM is the origin of a life-and-death signal that our laboratory detected from blood pressure of comatose patients that disappears before brain death ensues. At the same time, transcriptional upregulation of heme oxygenase-1 in RVLM by hypoxia-inducible factor-1α (HIF-1α plays a pro-life role in experimental brain death, and HIF-1α is subject to sumoylation activated by transient cerebral ischemia. It follows that sumoylation of HIF-1α in RVLM in response to hypoxia may play a modulatory role on brain stem cardiovascular regulation during experimental brain death. METHODOLOGY/PRINCIPAL FINDINGS: A clinically relevant animal model that employed mevinphos as the experimental insult in Sprague-Dawley rat was used. Biochemical changes in RVLM during distinct phenotypes in systemic arterial pressure spectrum that reflect maintained or defunct brain stem cardiovascular regulation were studied. Western blot analysis, EMSA, ELISA, confocal microscopy and immunoprecipitation demonstrated that drastic tissue hypoxia, elevated levels of proteins conjugated by small ubiquitin-related modifier-1 (SUMO-1, Ubc9 (the only known conjugating enzyme for the sumoylation pathway or HIF-1α, augmented sumoylation of HIF-1α, nucleus-bound translocation and enhanced transcriptional activity of HIF-1α in RVLM neurons took place preferentially during the pro-life phase of experimental brain death. Furthermore, loss-of-function manipulations by immunoneutralization of SUMO-1, Ubc9 or HIF-1α in RVLM blunted the upregulated nitric oxide synthase I/protein kinase G signaling cascade, which sustains the brain stem cardiovascular regulatory machinery during the pro-life phase. CONCLUSIONS

  7. Halofuginone Inhibits Angiogenesis and Growth in Implanted Metastatic Rat Brain Tumor Model-an MRI Study

    Directory of Open Access Journals (Sweden)

    Rinat Abramovitch

    2004-09-01

    Full Text Available Tumor growth and metastasis depend on angiogenesis; therefore, efforts are made to develop specific angiogenic inhibitors. Halofuginone (HF is a potent inhibitor of collagen type α1(I. In solid tumor models, HF has a potent antitumor and antiangiogenic effect in vivo, but its effect on brain tumors has not yet been evaluated. By employing magnetic resonance imaging (MRI, we monitored the effect of HF on tumor progression and vascularization by utilizing an implanted malignant fibrous histiocytoma metastatic rat brain tumor model. Here we demonstrate that treatment with HF effectively and dose-dependently reduced tumor growth and angiogenesis. On day 13, HF-treated tumors were fivefold smaller than control (P < .001. Treatment with HF significantly prolonged survival of treated animals (142%; P = .001. In HF-treated rats, tumor vascularization was inhibited by 30% on day 13 and by 37% on day 19 (P < .05. Additionally, HF treatment inhibited vessel maturation (P = .03. Finally, in HF-treated rats, we noticed the appearance of a few clusters of satellite tumors, which were distinct from the primary tumor and usually contained vessel cores. This phenomenon was relatively moderate when compared to previous reports of other antiangiogenic agents used to treat brain tumors. We therefore conclude that HF is effective for treatment of metastatic brain tumors.

  8. Intravenous transplantation of bone marrow mesenchymal stem cells promotes neural regeneration after traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Fatemeh Anbari; Mohammad Ali Khalili; Ahmad Reza Bahrami; Arezoo Khoradmehr; Fatemeh Sadeghian; Farzaneh Fesahat; Ali Nabi

    2014-01-01

    To investigate the supplement of lost nerve cells in rats with traumatic brain injury by intrave-nous administration of allogenic bone marrow mesenchymal stem cells, this study established a Wistar rat model of traumatic brain injury by weight drop impact acceleration method and ad-ministered 3 × 106 rat bone marrow mesenchymal stem cells via the lateral tail vein. At 14 days after cell transplantation, bone marrow mesenchymal stem cells differentiated into neurons and astrocytes in injured rat cerebral cortex and rat neurological function was improved significant-ly. These findings suggest that intravenously administered bone marrow mesenchymal stem cells can promote nerve cell regeneration in injured cerebral cortex, which supplement the lost nerve cells.

  9. Transcriptional profiling of adult neural stem-like cells from the human brain.

    Science.gov (United States)

    Sandberg, Cecilie Jonsgar; Vik-Mo, Einar O; Behnan, Jinan; Helseth, Eirik; Langmoen, Iver A

    2014-01-01

    There is a great potential for the development of new cell replacement strategies based on adult human neural stem-like cells. However, little is known about the hierarchy of cells and the unique molecular properties of stem- and progenitor cells of the nervous system. Stem cells from the adult human brain can be propagated and expanded in vitro as free floating neurospheres that are capable of self-renewal and differentiation into all three cell types of the central nervous system. Here we report the first global gene expression study of adult human neural stem-like cells originating from five human subventricular zone biopsies (mean age 42, range 33-60). Compared to adult human brain tissue, we identified 1,189 genes that were significantly up- and down-regulated in adult human neural stem-like cells (1% false discovery rate). We found that adult human neural stem-like cells express stem cell markers and have reduced levels of markers that are typical of the mature cells in the nervous system. We report that the genes being highly expressed in adult human neural stem-like cells are associated with developmental processes and the extracellular region of the cell. The calcium signaling pathway and neuroactive ligand-receptor interactions are enriched among the most differentially regulated genes between adult human neural stem-like cells and adult human brain tissue. We confirmed the expression of 10 of the most up-regulated genes in adult human neural stem-like cells in an additional sample set that included adult human neural stem-like cells (n = 6), foetal human neural stem cells (n = 1) and human brain tissues (n = 12). The NGFR, SLITRK6 and KCNS3 receptors were further investigated by immunofluorescence and shown to be heterogeneously expressed in spheres. These receptors could potentially serve as new markers for the identification and characterisation of neural stem- and progenitor cells or as targets for manipulation of cellular fate.

  10. Control of abdominal muscles by brain stem respiratory neurons in the cat

    Science.gov (United States)

    Miller, Alan D.; Ezure, Kazuhisa; Suzuki, Ichiro

    1985-01-01

    The nature of the control of abdominal muscles by the brain stem respiratory neurons was investigated in decerebrate unanesthetized cats. First, it was determined which of the brain stem respiratory neurons project to the lumbar cord (from which the abdominal muscles receive part of their innervation), by stimulating the neurons monopolarly. In a second part of the study, it was determined if lumbar-projecting respiratory neurons make monosynaptic connections with abdominal motoneurons; in these experiments, discriminate spontaneous spikes of antidromically acivated expiratory (E) neurons were used to trigger activity from both L1 and L2 nerves. A large projection was observed from E neurons in the caudal ventral respiratory group to the contralateral upper lumber cord. However, cross-correlation experiments found only two (out of 47 neuron pairs tested) strong monosynaptic connections between brain stem neurons and abdominal motoneurons.

  11. Patient-derived stem cells: pathways to drug discovery for brain diseases

    Directory of Open Access Journals (Sweden)

    Alan eMackay-Sim

    2013-03-01

    Full Text Available The concept of drug discovery through stem cell biology is based on technological developments whose genesis is now coincident. The first is automated cell microscopy with concurrent advances in image acquisition and analysis, known as high content screening (HCS. The second is patient-derived stem cells for modelling the cell biology of brain diseases. HCS has developed from the requirements of the pharmaceutical industry for high throughput assays to screen thousands of chemical compounds in the search for new drugs. HCS combines new fluorescent probes with automated microscopy and computational power to quantify the effects of compounds on cell functions. Stem cell biology has advanced greatly since the discovery of genetic reprogramming of somatic cells into induced pluripotent stem cells (iPSCs. There is now a rush of papers describing their generation from patients with various diseases of the nervous system. Although the majority of these have been genetic diseases, iPSCs have been generated from patients with complex diseases (schizophrenia and sporadic Parkinson’s disease. Some genetic diseases are also modelled in embryonic stem cells generated from blastocysts rejected during in vitro fertilisation. Neural stem cells have been isolated from post-mortem brain of Alzheimer’s patients and neural stem cells generated from biopsies of the olfactory organ of patients is another approach. These olfactory neurosphere-derived cells demonstrate robust disease-specific phenotypes in patients with schizophrenia and Parkinson’s disease. High content screening is already in use to find small molecules for the generation and differentiation of embryonic stem cells and induced pluripotent stem cells. The challenges for using stem cells for drug discovery are to develop robust stem cell culture methods that meet the rigorous requirements for repeatable, consistent quantities of defined cell types at the industrial scale necessary for high

  12. TYPE-2 DIABETES MELLITUS AND BRAIN STEM EVOKED RESPONSE AUDIOMETRY: A CASE CONTROL STUDY

    Directory of Open Access Journals (Sweden)

    Praveen S

    2016-01-01

    Full Text Available BACKGROUND AND OBJECTIVE Type-2 Diabetes Mellitus (T2DM causes pathophysiological changes in multiple organ system. The peripheral, autonomic and central neuropathy is known to occur in T2DM, which can be studied electrophysiologically. AIM Present study is aimed to evaluate functional integrity of auditory pathway in T2DM by Brainstem Evoked Response Audiometry (BERA. MATERIAL AND METHOD In the present case control study, BERA was recorded from the scalp of 20 T2DM patients aged 30-65 years and were compared with age matched 20 healthy controls. The BERA was performed using EMG Octopus, Clarity Medical Pvt. Ltd. The latencies of wave I, III, V and Wave I-III, I-V and III-V interpeak latencies of both right and left ear were recorded at 70dBHL. STATISTICAL RESULT AND USE Mean±SD of latencies of wave I, III, V and interpeak latency of I-III, I-V and III-V were estimated of T2DM and healthy controls. The significant differences between the two groups were assessed using unpaired student ‘t’ test for T2DM and control groups using GraphPad QuickCalcs calculator. P value <0.05 was considered to be significant. RESULT In T2DM BERA study revealed statistically significant (p<0.05 prolonged latencies of wave I, III and V in both right (1.81±0.33ms, 3.96±0.32ms, 5.60±0.25ms and left (1.96±0.24ms, 3.79±0.22ms, 5.67±0.25ms ear as compared to controls at 70dB. Wave III-V interpeak latency of left ear (1.87±0.31, 1.85±0.41ms and wave I-III (2.51±0.42ms, 1.96±0.48ms and III-V (2.01±0.43ms, 1.76±0.45ms of right ear was prolonged in diabetic patient as compared to controls, although no significant difference was obtained (p<0.05. INTERPRETATION AND CONCLUSION Increase in absolute latencies and interpeak latencies inT2DM patients suggest involvement of central neuronal axis at the level of brain stem and midbrain.

  13. Efficient and rapid derivation of primitive neural stem cells and generation of brain subtype neurons from human pluripotent stem cells.

    Science.gov (United States)

    Yan, Yiping; Shin, Soojung; Jha, Balendu Shekhar; Liu, Qiuyue; Sheng, Jianting; Li, Fuhai; Zhan, Ming; Davis, Janine; Bharti, Kapil; Zeng, Xianmin; Rao, Mahendra; Malik, Nasir; Vemuri, Mohan C

    2013-11-01

    Human pluripotent stem cells (hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, are unique cell sources for disease modeling, drug discovery screens, and cell therapy applications. The first step in producing neural lineages from hPSCs is the generation of neural stem cells (NSCs). Current methods of NSC derivation involve the time-consuming, labor-intensive steps of an embryoid body generation or coculture with stromal cell lines that result in low-efficiency derivation of NSCs. In this study, we report a highly efficient serum-free pluripotent stem cell neural induction medium that can induce hPSCs into primitive NSCs (pNSCs) in 7 days, obviating the need for time-consuming, laborious embryoid body generation or rosette picking. The pNSCs expressed the neural stem cell markers Pax6, Sox1, Sox2, and Nestin; were negative for Oct4; could be expanded for multiple passages; and could be differentiated into neurons, astrocytes, and oligodendrocytes, in addition to the brain region-specific neuronal subtypes GABAergic, dopaminergic, and motor neurons. Global gene expression of the transcripts of pNSCs was comparable to that of rosette-derived and human fetal-derived NSCs. This work demonstrates an efficient method to generate expandable pNSCs, which can be further differentiated into central nervous system neurons and glia with temporal, spatial, and positional cues of brain regional heterogeneity. This method of pNSC derivation sets the stage for the scalable production of clinically relevant neural cells for cell therapy applications in good manufacturing practice conditions.

  14. Donor-derived brain tumor following neural stem cell transplantation in an ataxia telangiectasia patient.

    Directory of Open Access Journals (Sweden)

    Ninette Amariglio

    2009-02-01

    Full Text Available BACKGROUND: Neural stem cells are currently being investigated as potential therapies for neurodegenerative diseases, stroke, and trauma. However, concerns have been raised over the safety of this experimental therapeutic approach, including, for example, whether there is the potential for tumors to develop from transplanted stem cells. METHODS AND FINDINGS: A boy with ataxia telangiectasia (AT was treated with intracerebellar and intrathecal injection of human fetal neural stem cells. Four years after the first treatment he was diagnosed with a multifocal brain tumor. The biopsied tumor was diagnosed as a glioneuronal neoplasm. We compared the tumor cells and the patient's peripheral blood cells by fluorescent in situ hybridization using X and Y chromosome probes, by PCR for the amelogenin gene X- and Y-specific alleles, by MassArray for the ATM patient specific mutation and for several SNPs, by PCR for polymorphic microsatellites, and by human leukocyte antigen (HLA typing. Molecular and cytogenetic studies showed that the tumor was of nonhost origin suggesting it was derived from the transplanted neural stem cells. Microsatellite and HLA analysis demonstrated that the tumor is derived from at least two donors. CONCLUSIONS: This is the first report of a human brain tumor complicating neural stem cell therapy. The findings here suggest that neuronal stem/progenitor cells may be involved in gliomagenesis and provide the first example of a donor-derived brain tumor. Further work is urgently needed to assess the safety of these therapies.

  15. How stem cells speak with host immune cells in inflammatory brain diseases.

    Science.gov (United States)

    Pluchino, Stefano; Cossetti, Chiara

    2013-09-01

    Advances in stem cell biology have raised great expectations that diseases and injuries of the central nervous system (CNS) may be ameliorated by the development of non-hematopoietic stem cell medicines. Yet, the application of adult stem cells as CNS therapeutics is challenging and the interpretation of some of the outcomes ambiguous. In fact, the initial idea that stem cell transplants work only via structural cell replacement has been challenged by the observation of consistent cellular signaling between the graft and the host. Cellular signaling is the foundation of coordinated actions and flexible responses, and arises via networks of exchanging and interacting molecules that transmit patterns of information between cells. Sustained stem cell graft-to-host communication leads to remarkable trophic effects on endogenous brain cells and beneficial modulatory actions on innate and adaptive immune responses in vivo, ultimately promoting the healing of the injured CNS. Among a number of adult stem cell types, mesenchymal stem cells (MSCs) and neural stem/precursor cells (NPCs) are being extensively investigated for their ability to signal to the immune system upon transplantation in experimental CNS diseases. Here, we focus on the main cellular signaling pathways that grafted MSCs and NPCs use to establish a therapeutically relevant cross talk with host immune cells, while examining the role of inflammation in regulating some of the bidirectionality of these communications. We propose that the identification of the players involved in stem cell signaling might contribute to the development of innovative, high clinical impact therapeutics for inflammatory CNS diseases.

  16. Real Time Imaging of Biomarkers in the Parkinson's Brain Using Mini-Implantable Biosensors. II. Pharmaceutical Therapy with Bromocriptine

    OpenAIRE

    Patricia A. Broderick; Kolodny, Edwin H.

    2009-01-01

    We used Neuromolecular Imaging (NMI) and trademarked BRODERICK PROBE® mini-implantable biosensors, to selectively and separately detect neuro-transmitters in vivo, on line, within seconds in the dorsal striatal brain of the Parkinson’s Disease (PD) animal model. We directly compared our results derived from PD to the normal striatal brain of the non-Parkinson’s Disease (non-PD) animal. This advanced biotechnology enabled the imaging of dopamine (DA), serotonin (5-HT), homovanillic acid (HVA) ...

  17. Real Time Imaging of Biomarkers in the Parkinson's Brain Using Mini-Implantable Biosensors. II. Pharmaceutical Therapy with Bromocriptine

    OpenAIRE

    Patricia A. Broderick; Kolodny, Edwin H.

    2009-01-01

    We used Neuromolecular Imaging (NMI) and trademarked BRODERICK PROBE® mini-implantable biosensors, to selectively and separately detect neurotransmitters in vivo, on line, within seconds in the dorsal striatal brain of the Parkinson’s Disease (PD) animal model. We directly compared our results derived from PD to the normal striatal brain of the non-Parkinson’s Disease (non-PD) animal. This advanced biotechnology enabled the imaging of dopamine (DA), serotonin (5-HT), homovanillic acid (HVA) a...

  18. Gap junction proteins in the blood-brain barrier control nutrient-dependent reactivation of Drosophila neural stem cells.

    Science.gov (United States)

    Spéder, Pauline; Brand, Andrea H

    2014-08-11

    Neural stem cells in the adult brain exist primarily in a quiescent state but are reactivated in response to changing physiological conditions. How do stem cells sense and respond to metabolic changes? In the Drosophila CNS, quiescent neural stem cells are reactivated synchronously in response to a nutritional stimulus. Feeding triggers insulin production by blood-brain barrier glial cells, activating the insulin/insulin-like growth factor pathway in underlying neural stem cells and stimulating their growth and proliferation. Here we show that gap junctions in the blood-brain barrier glia mediate the influence of metabolic changes on stem cell behavior, enabling glia to respond to nutritional signals and reactivate quiescent stem cells. We propose that gap junctions in the blood-brain barrier are required to translate metabolic signals into synchronized calcium pulses and insulin secretion.

  19. Physics strategies for sparing neural stem cells during whole-brain radiation treatments

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, Neil; Chuang, Cynthia; Pouliot, Jean; Hwang, Andrew; Barani, Igor J. [Department of Radiation Oncology, University of California San Francisco, San Francisco, California 94143-1708 (United States)

    2011-10-15

    Purpose: Currently, there are no successful long-term treatments or preventive strategies for radiation-induced cognitive impairments, and only a few possibilities have been suggested. One such approach involves reducing the dose to neural stem cell compartments (within and outside of the hippocampus) during whole-brain radiation treatments for brain metastases. This study investigates the fundamental physics issues associated with the sparing of neural stem cells during photon radiotherapy for brain metastases. Methods: Several factors influence the stem cell dose: intracranial scattering, collimator leakage, beam energy, and total number of beams. The relative importance of these factors is investigated through a set of radiation therapy plans, which are all variations of an initial 6 MV intensity-modulated radiation therapy (IMRT) plan designed to simultaneously deliver a whole-brain dose of 30 Gy and maximally reduce stem cell compartment dose. Additionally, an in-house leaf segmentation algorithm was developed that utilizes jaw motion to minimize the collimator leakage. Results: The plans are all normalized such that 50% of the PTV receives 30 Gy. For the initial 6 MV IMRT plan, 50% of the stem cells receive a dose greater than 6.3 Gy. Calculations indicate that 3.6 Gy of this dose originates from intracranial scattering. The jaw-tracking segmentation algorithm, used in conjunction with direct machine parameter optimization, reduces the 50% stem cell dose to 4.3 and 3.7 Gy for 6 and 10 MV treatment beams, respectively. Conclusions: Intracranial scattering alone is responsible for a large dose contribution to the stem cell compartment. It is, therefore, important to minimize other contributing factors, particularly the collimator leakage, to maximally reduce dose to these critical structures. The use of collimator jaw tracking in conjunction with modern collimators can minimize this leakage.

  20. Brain stem and cerebellar atrophy in chronic progressive neuro-Behçet's disease

    Energy Technology Data Exchange (ETDEWEB)

    Kanoto, Masafumi, E-mail: mkanoto@med.id.yamagata-u.ac.jp [Department of Diagnostic Radiology, Faculty of Medicine, Yamagata University, Iida-Nishi 2-2-2, 990-9585 Yamagata (Japan); Hosoya, Takaaki, E-mail: thosoya@med.id.yamagata-u.ac.jp [Department of Diagnostic Radiology, Faculty of Medicine, Yamagata University, Iida-Nishi 2-2-2, 990-9585 Yamagata (Japan); Toyoguchi, Yuuki, E-mail: c-elegans_0201g@mail.goo.ne.jp [Department of Diagnostic Radiology, Faculty of Medicine, Yamagata University, Iida-Nishi 2-2-2, 990-9585 Yamagata (Japan); Oda, Atsuko, E-mail: a.oda@med.id.yamagata-u.ac.jp [Department of Diagnostic Radiology, Faculty of Medicine, Yamagata University, Iida-Nishi 2-2-2, 990-9585 Yamagata (Japan)

    2013-01-15

    Purpose: Chronic progressive neuro-Behçet's disease (CPNBD) resembles multiple sclerosis (MS) on patient background and image findings, and therefore is difficult to diagnose. The purpose is to identify the characteristic magnetic resonance imaging (MRI) findings of CPNBD and to clarify the differences between the MRI findings of CPNBD and those of MS. Materials and methods: The subjects consist of a CPNBD group (n = 4; 1 male and 3 females; mean age, 51 y.o.), a MS group (n = 19; 3 males and 16 females; mean age, 45 y.o.) and a normal control group (n = 23; 10 males and 13 females; mean age, 45 y.o.). Brain stem atrophy, cerebellar atrophy, and leukoencephalopathy were retrospectively evaluated in each subjects. In middle sagittal brain MR images, the prepontine distance was measured as an indirect index of brain stem and cerebellar atrophy and the pontine and mesencephalic distance was measured as a direct index of brain stem atrophy. These indexes were statistically analyzed. Results: Brain stem atrophy, cerebellar atrophy, and leukoencephalopathy were seen in all CPNBD cases. Prepontine distance was significantly different between the CPNBD group and the MS group (p < 0.05), and between the CPNBD group and the normal control group (p < 0.001). Pontine and mesencephalic distance were significantly different between the CPNBD group and the MS group (p < 0.001, p < 0.01 respectively), and between the CPNBD group and the normal control group (p < 0.001). Conclusions: Chronic progressive neuro-Behçet's disease should be considered in patients with brain stem and cerebellar atrophy in addition to leukoencephalopathy similar to that seen in multiple sclerosis.

  1. Evidence of a visual-to-auditory cross-modal sensory gating phenomenon as reflected by the human P50 event-related brain potential modulation.

    Science.gov (United States)

    Lebib, Riadh; Papo, David; de Bode, Stella; Baudonnière, Pierre Marie

    2003-05-08

    We investigated the existence of a cross-modal sensory gating reflected by the modulation of an early electrophysiological index, the P50 component. We analyzed event-related brain potentials elicited by audiovisual speech stimuli manipulated along two dimensions: congruency and discriminability. The results showed that the P50 was attenuated when visual and auditory speech information were redundant (i.e. congruent), in comparison with this same event-related potential component elicited with discrepant audiovisual dubbing. When hard to discriminate, however, bimodal incongruent speech stimuli elicited a similar pattern of P50 attenuation. We concluded to the existence of a visual-to-auditory cross-modal sensory gating phenomenon. These results corroborate previous findings revealing a very early audiovisual interaction during speech perception. Finally, we postulated that the sensory gating system included a cross-modal dimension.

  2. Brain-derived neurotrophic factor ameliorates brain stem cardiovascular dysregulation during experimental temporal lobe status epilepticus.

    Directory of Open Access Journals (Sweden)

    Ching-Yi Tsai

    Full Text Available BACKGROUND: Status epilepticus (SE is an acute, prolonged epileptic crisis with a mortality rate of 20-30%; the underlying mechanism is not completely understood. We assessed the hypothesis that brain stem cardiovascular dysregulation occurs during SE because of oxidative stress in rostral ventrolateral medulla (RVLM, a key nucleus of the baroreflex loop; to be ameliorated by brain-derived neurotrophic factor (BDNF via an antioxidant action. METHODOLOGY/PRINCIPAL FINDINGS: In a clinically relevant experimental model of temporal lobe SE (TLSE using Sprague-Dawley rats, sustained hippocampal seizure activity was accompanied by progressive hypotension that was preceded by a reduction in baroreflex-mediated sympathetic vasomotor tone; heart rate and baroreflex-mediated cardiac responses remained unaltered. Biochemical experiments further showed concurrent augmentation of superoxide anion, phosphorylated p47(phox subunit of NADPH oxidase and mRNA or protein levels of BDNF, tropomyosin receptor kinase B (TrkB, angiotensin AT1 receptor subtype (AT1R, nitric oxide synthase II (NOS II or peroxynitrite in RVLM. Whereas pretreatment by microinjection bilaterally into RVLM of a superoxide dismutase mimetic (tempol, a specific antagonist of NADPH oxidase (apocynin or an AT1R antagonist (losartan blunted significantly the augmented superoxide anion or phosphorylated p47(phox subunit in RVLM, hypotension and the reduced baroreflex-mediated sympathetic vasomotor tone during experimental TLSE, pretreatment with a recombinant human TrkB-Fc fusion protein or an antisense bdnf oligonucleotide significantly potentiated all those events, alongside peroxynitrite. However, none of the pretreatments affected the insignificant changes in heart rate and baroreflex-mediated cardiac responses. CONCLUSIONS/SIGNIFICANCE: We conclude that formation of peroxynitrite by a reaction between superoxide anion generated by NADPH oxidase in RVLM on activation by AT1R and NOS II

  3. Design of a Small Modified Minkowski Fractal Antenna for Passive Deep Brain Stimulation Implants

    Directory of Open Access Journals (Sweden)

    Sara Manafi

    2014-01-01

    Full Text Available A small planar modified Minkowski fractal antenna is designed and simulated in dual frequency bands (2.4 and 5.8 GHz for wireless energy harvesting by deep brain stimulation (DBS devices. The designed antenna, physically being confined inside a miniaturized structure, can efficiently convert the wireless signals in dual ISM frequency bands to the energy source to recharge the DBS battery or power the pulse generator directly. The performance metrics such as the return loss, the specific absorption rate (SAR, and the radiation pattern within skin and muscle-fat-skin tissues are evaluated for the designed antenna. The gain of the proposed antenna is 3.2 dBi at 2.4 GHz and 4.7 dBi at 5.8 GHz; also the averaged SAR of the antenna in human body tissue is found to be well below the legally allowed limit at both frequency bands. The link budget shows the received power at the distance of 25 cm at 2.4 GHz and 5.8 GHz are around 0.4 mW and 0.04 mW, which can empower the DBS implant. The large operational bandwidth, the physical compactness, and the efficiency in wireless signal reception make this antenna suitable in being used in implanted biomedical devices such as DBS pulse generators.

  4. A wirelessly controlled implantable LED system for deep brain optogenetic stimulation

    Directory of Open Access Journals (Sweden)

    Mark A. Rossi

    2015-02-01

    Full Text Available In recent years optogenetics has rapidly become an essential technique in neuroscience. Its temporal and spatial specificity, combined with efficacy in manipulating neuronal activity, are especially useful in studying the behavior of awake behaving animals. Conventional optogenetics, however, requires the use of lasers and optic fibers, which can place considerable restrictions on behavior. Here we combined a wirelessly controlled interface and small implantable light-emitting diode (LED that allows flexible and precise placement of light source to illuminate any brain area. We tested this wireless LED system in vivo, in transgenic mice expressing channelrhodopsin-2 in striatonigral neurons expressing D1-like dopamine receptors. In all mice tested, we were able to elicit movements reliably. The frequency of twitches induced by high power stimulation is proportional to the frequency of stimulation. At lower power, contraversive turning was observed. Moreover, the implanted LED remains effective over 50 days after surgery, demonstrating the long-term stability of the light source. Our results show that the wireless LED system can be used to manipulate neural activity chronically in behaving mice without impeding natural movements.

  5. In vitro analysis with human bone marrow stem cells on Ti-15Mo alloy for dental and orthopedic implants application

    Directory of Open Access Journals (Sweden)

    N.T.C. Oliveira

    2011-03-01

    Full Text Available Aim: Nowadays, research on orthopedic and dental implants is focused on titanium alloys for their mechanical properties and corrosion resistance in the human body environment. Another important aspect to be investigated is their surface topography, which is very important to osseointegration. With laser beam irradiation for roughening the implants surface an easier control of the microtopography is achieved, and surface contamination is avoided. The aim of this study was to assess human bone marrow stem cells response to a newly developed titanium alloy, Ti-15Mo, with surface topography modified by laser beam irradiation. Materials and methods: A total of 10 Ti machined disks (control, 10 Ti-15Mo machined disks and 10 Ti-15Mo disks treated by laser beam-irradiation were prepared. To study how Ti-15Mo surface topografy can induce osteoblast differentiation in mesenchymal stem cells, the expression levels of bone related genes and mesenchymal stem cells marker were analyzed, using real time Reverse Transcription-Polymerase Chain Reaction. Results: In Test 1 (comparison between Ti-15Mo machined disks and Ti-machined disks quantitative real-time RT–PCR showed a significant induction of ALPL, FOSL1 and SPP1, which increase 20% or more. In Test 2 (comparison between Ti-15Mo laser treated disks and Ti-machined disks all investigated genes were up-regulated. By comparing Test 1 and Test 2 it was detected that COL1A1, COL3A1, FOSL1 and ENG sensibly increased their expression whereas RUNX2, ALPL and SPP1 expression remained substantially unchanged. Conclusion: The present study demonstrated that laser treated Ti-15Mo alloys are promising materials for implants application.

  6. Reconstruction of brain circuitry by neural transplants generated from pluripotent stem cells.

    Science.gov (United States)

    Thompson, Lachlan H; Björklund, Anders

    2015-07-01

    Pluripotent stem cells (embryonic stem cells, ESCs, and induced pluripotent stem cells, iPSCs) have the capacity to generate neural progenitors that are intrinsically patterned to undergo differentiation into specific neuronal subtypes and express in vivo properties that match the ones formed during normal embryonic development. Remarkable progress has been made in this field during recent years thanks to the development of more refined protocols for the generation of transplantable neuronal progenitors from pluripotent stem cells, and the access to new tools for tracing of neuronal connectivity and assessment of integration and function of grafted neurons. Recent studies in brains of neonatal mice or rats, as well as in rodent models of brain or spinal cord damage, have shown that ESC- or iPSC-derived neural progenitors can be made to survive and differentiate after transplantation, and that they possess a remarkable capacity to extend axons over long distances and become functionally integrated into host neural circuitry. Here, we summarize these recent developments in the perspective of earlier studies using intracerebral and intraspinal transplants of primary neurons derived from fetal brain, with special focus on the ability of human ESC- and iPSC-derived progenitors to reconstruct damaged neural circuitry in cortex, hippocampus, the nigrostriatal system and the spinal cord, and we discuss the intrinsic and extrinsic factors that determine the growth properties of the grafted neurons and their capacity to establish target-specific long-distance axonal connections in the damaged host brain.

  7. Paediatric brain-stem gliomas: MRI, FDG-PET and histological grading correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jong Won; Kim, In-One; Cheon, Jung-Eun; Kim, Woo Sun; Moon, Sung Gyu; Kim, Tae Jung; Yeon, Kyung Mo [Seoul National University Hospital, Department of Radiology, Seoul (Korea); Chi, Je Geun [Seoul National University College of Medicine, Department of Pathology, Seoul (Korea); Wang, Kyu-Chang [Seoul National University College of Medicine, Department of Neurosurgery, Seoul (Korea); Chung, June Key [Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul (Korea)

    2006-09-15

    MRI and FDG-PET may predict the histological grading of paediatric brain-stem gliomas. To assess MRI findings and metabolic imaging using FDG-PET of brain-stem gliomas based on histological grading. Included in the study were 20 paediatric patients (age 3-14 years, mean 8.2 years) with brain-stem glioma (five glioblastomas, ten anaplastic astrocytomas and five low-grade astrocytomas). MR images were assessed for the anatomical site of tumour origin, focality, pattern of tumour growth, and enhancement. All glioblastomas were located in the pons and showed diffuse pontine enlargement with focally exophytic features. Eight anaplastic astrocytomas were located in the pons and demonstrated diffuse pontine enlargement without exophytic features. Low-grade astrocytomas were located in the pons, midbrain or medulla and showed focally exophytic growth features and peripheral enhancement. In 12 patients in whom FDG-PET was undertaken, glioblastomas showed hypermetabolic or hypometabolic lesions, anaplastic astrocytomas showed no metabolic change or hypometabolic lesions and low-grade astrocytomas showed hypometabolism compared with the cerebellum. MRI findings correlated well with histological grading of brain-stem gliomas and MRI may therefore predict the histological grading. FDG-PET may be helpful in differentiating between anaplastic astrocytoma and glioblastomas among high-grade tumours. (orig.)

  8. Intranasal mesenchymal stem cell treatment for neonatal brain damage : long-term cognitive and sensorimotor improvement

    NARCIS (Netherlands)

    Donega, Vanessa; van Velthoven, Cindy T J; Nijboer, Cora H; van Bel, Frank; Kas, Martien J H; Kavelaars, Annemieke; Heijnen, Cobi J

    2013-01-01

    Mesenchymal stem cell (MSC) administration via the intranasal route could become an effective therapy to treat neonatal hypoxic-ischemic (HI) brain damage. We analyzed long-term effects of intranasal MSC treatment on lesion size, sensorimotor and cognitive behavior, and determined the therapeutic wi

  9. Me, Myself and My Brain Implant: Deep Brain Stimulation Raises Questions of Personal Authenticity and Alienation.

    Science.gov (United States)

    Kraemer, Felicitas

    2013-01-01

    In this article, I explore select case studies of Parkinson patients treated with deep brain stimulation (DBS) in light of the notions of alienation and authenticity. While the literature on DBS has so far neglected the issues of authenticity and alienation, I argue that interpreting these cases in terms of these concepts raises new issues for not only the philosophical discussion of neuro-ethics of DBS, but also for the psychological and medical approach to patients under DBS. In particular, I suggest that the experience of alienation and authenticity varies from patient to patient with DBS. For some, alienation can be brought about by neurointerventions because patients no longer feel like themselves. But, on the other hand, it seems alienation can also be cured by DBS as other patients experience their state of mind as authentic under treatment and retrospectively regard their former lives without stimulation as alienated. I argue that we must do further research on the relevance of authenticity and alienation to patients treated with DBS in order to gain a deeper philosophical understanding, and to develop the best evaluative criterion for the behavior of DBS patients.

  10. Differences in brain circuitry for appetitive and reactive aggression as revealed by realistic auditory scripts

    Directory of Open Access Journals (Sweden)

    James Kenneth Moran

    2014-12-01

    Full Text Available Aggressive behavior is thought to divide into two motivational elements: The first being a self-defensively motivated aggression against threat and a second, hedonically motivated ‘appetitive’ aggression. Appetitive aggression is the less understood of the two, often only researched within abnormal psychology. Our approach is to understand it as a universal and adaptive response, and examine the functional neural activity of ordinary men (N=50 presented with an imaginative listening task involving a murderer describing a kill. We manipulated motivational context in a between-subjects design to evoke appetitive or reactive aggression, against a neutral control, measuring activity with Magnetoencephalography (MEG. Results show differences in left frontal regions in delta (2-5 Hz and alpha band (8-12 Hz for aggressive conditions and right parietal delta activity differentiating appetitive and reactive aggression. These results validate the distinction of reward-driven appetitive aggression from reactive aggression in ordinary populations at the level of functional neural brain circuitry.

  11. Neurotransmission to parasympathetic cardiac vagal neurons in the brain stem is altered with left ventricular hypertrophy-induced heart failure.

    Science.gov (United States)

    Cauley, Edmund; Wang, Xin; Dyavanapalli, Jhansi; Sun, Ke; Garrott, Kara; Kuzmiak-Glancy, Sarah; Kay, Matthew W; Mendelowitz, David

    2015-10-01

    Hypertension, cardiac hypertrophy, and heart failure (HF) are widespread and debilitating cardiovascular diseases that affect nearly 23 million people worldwide. A distinctive hallmark of these cardiovascular diseases is autonomic imbalance, with increased sympathetic activity and decreased parasympathetic vagal tone. Recent device-based approaches, such as implantable vagal stimulators that stimulate a multitude of visceral sensory and motor fibers in the vagus nerve, are being evaluated as new therapeutic approaches for these and other diseases. However, little is known about how parasympathetic activity to the heart is altered with these diseases, and this lack of knowledge is an obstacle in the goal of devising selective interventions that can target and selectively restore parasympathetic activity to the heart. To identify the changes that occur within the brain stem to diminish the parasympathetic cardiac activity, left ventricular hypertrophy was elicited in rats by aortic pressure overload using a transaortic constriction approach. Cardiac vagal neurons (CVNs) in the brain stem that generate parasympathetic activity to the heart were identified with a retrograde tracer and studied using patch-clamp electrophysiological recordings in vitro. Animals with left cardiac hypertrophy had diminished excitation of CVNs, which was mediated both by an augmented frequency of spontaneous inhibitory GABAergic neurotransmission (with no alteration of inhibitory glycinergic activity) as well as a diminished amplitude and frequency of excitatory neurotransmission to CVNs. Opportunities to alter these network pathways and neurotransmitter receptors provide future targets of intervention in the goal to restore parasympathetic activity and autonomic balance to the heart in cardiac hypertrophy and other cardiovascular diseases.

  12. Tropism mechanism of stem cells targeting injured brain tissues by stromal cell-derived factor-1

    Institute of Scientific and Technical Information of China (English)

    ZHANG Sai; LIU Xiao-zhi; LIU Zhen-lin; SHANG Chong-zhi; HU Qun-liang

    2009-01-01

    Objective: To explore the role and function of stromal cell-derived factor- 1 (SDF- 1) in stem cells migrating into injured brain area.Methods: Rat-derived nerve stem cells (NSCs) were isolated and cultured routinely. Transwell system was used to observe the migration ability of NSCs into injured nerve cells. Immunocytochemistry was used to explore the expression of chemotactic factor receptor-4 (CXCR-4) in NSCs. In vivo, we applied immunofluorescence technique to observe the migration of NSCs into injured brain area. Immunofluorescence technique and Western blotting were used to test expression level of SDF- 1. After AMD3100 (a special chemical blocker) blocking CXCR-4, the migration ability of NSCs was tested in vivo and in vitro, respectively.Results: NSCs displayed specific tropism for injured nerve cells or traumatic brain area in vivo and in vitro. The expression level of SDF-1 in traumatic brain area increased remarkably and the expression level of CXCR-4 in the NSCs increased simultaneously. After AMD3100 blocking the expression of CXCR-4, the migration ability of NSCs decreased significantly both in vivo and in vitro.Conclusions: SDF-1 may play a key role in stem cells migrating into injured brain area through specially combining with CXCR-4.

  13. MRI measurements of the brain stem and cerebellum in high functioning autistic children

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Toshiaki; Tayama, Masanobu; Miyazaki, Masahito; Murakawa, Kazuyoshi; Kuroda, Yasuhiro (Tokushima Univ. (Japan). School of Medicine)

    1994-01-01

    To determine involvements of the brain stem and/or cerebellum in autism, we compared midsagittal magnetic resonance images of the brains of high functioning autistic children with those of normal controls. We found that the midbrain and medulla oblongata were significantly smaller in these autistic children than in the control children. The pons area did not differ between the two groups, nor was there any difference in the cerebellar vermis area. The ratio of the brain stem and cerebellum to the posterior fossa area did not differ significantly between the high functioning autistic and the control children. The development of the cerebellar vermis area was delayed in autistic children as compared with that in the control children. Thus, it was suggested that significant anatomical changes in the midbrain and medulla oblongata existed in the autistic children. (author).

  14. Adult stem cells properties in terms of commitment, aging and biological safety of grit-blasted and Acid-etched ti dental implants surfaces.

    Science.gov (United States)

    Gardin, Chiara; Ferroni, Letizia; Bressan, Eriberto; Calvo-Guirado, José L; Degidi, Marco; Piattelli, Adriano; Zavan, Barbara

    2014-01-01

    Titanium (Ti) is one of the most widely used biomaterials for manufacturing dental implants. The implant surface properties strongly influence osseointegration. The aim of the present study was to in vitro investigate the characteristics of Ti dental implants in terms of mutagenicity, hemocompatibility, biocompatibility, osteoinductivity and biological safety. The Ames test was used to test the mutagenicity of the Ti dental implants, and the hemolysis assay for evaluating their hemocompatibility. Human adipose - derived stem cells (ADSCs) were then seeded onto these implants in order to evaluate their cytotoxicity. Gene expression analyzing with real-time PCR was carried out to investigate the osteoinductivity of the biomaterials. Finally, the genetic stability of the cells cultured onto dental implants was determined by karyotyping. Our results demonstrated that Ti dental implants are not mutagenic, do not cause hemolysis, and are biocompatible. The MTT assay revealed that ADSCs, seeded on Ti dental implants, proliferate up to 30 days in culture. Moreover, ADSCs loaded on Ti dental implants show a substantial expression of some osteoblast specific markers, such as COL1A1, OPN, ALPL, and RUNX2, as well as chromosomal stability after 30 days of culture in a medium without osteogenic factors. In conclusion, the grit-blasted and acid-etched treatment seems to favor the adhesion and proliferation of ADSCs and improve the osteoinductivity of Ti dental implant surfaces.

  15. Brain activation in response to visceral stimulation in rats with amygdala implants of corticosterone: an FMRI study.

    Directory of Open Access Journals (Sweden)

    Anthony C Johnson

    Full Text Available BACKGROUND: Although visceral pain of gastrointestinal (GI origin is the major complaint in patients with irritable bowel syndrome (IBS it remains poorly understood. Brain imaging studies suggest a defect in brain-gut communication in IBS with a greater activation of central arousal circuits including the amygdala. Previously, we found that stereotaxic implantation of corticosterone (CORT onto the amygdala in rats induced anxiety and colonic hypersensitivity. In the present study we used functional magnetic resonance imaging (fMRI to identify specific brain sites activated in a rat model characterized by anxiety and colonic hypersensitivity. METHODOLOGY/PRINCIPAL FINDINGS: Anesthetized male rats received micropellets (30 microg each of either CORT or cholesterol (CHOL, to serve as a control, implanted stereotaxically on the dorsal margin of each amygdala. Seven days later, rats were anesthetized and placed in the fMRI magnet (7T. A series of isobaric colorectal balloon distensions (CRD - 90s 'off', 30s 'on', 8 replicates at two pressures (40 and 60 mmHg were performed in a standard block-design. Cross correlation statistical analysis was used to determine significant differences between distended and non-distended states in CORT and CHOL-treated animals. Analysis of the imaging data demonstrated greater overall brain activation in response to CRD in rats with CORT implants compared to CHOL controls. Additionally, CORT implants produced significant positive bilateral increases in MRI signal in response to CRD in specific nuclei known as integration sites important in anxiety and pain perception. CONCLUSIONS AND SIGNIFICANCE: These data indicate that chronic exposure of the amygdala to elevated levels of CORT enhances overall brain activation in response to CRD, and identified other specific brain regions activated in response to mechanical distension of the colon. These results demonstrate the feasibility of performing fMRI imaging in a rodent

  16. CT-guided stereotaxic implantation of Ommaya reservoir for cystic brain tumor

    Energy Technology Data Exchange (ETDEWEB)

    Nakasato, Nobukazu; Niizuma, Hiroshi; Johkura, Hidefumi; Katoh, Seiya; Otsuki, Taisuke; Katakura, Ryuichi; Suzuki, Jiro

    1988-02-01

    We report the use of CT-guided stereotaxic system to implant Ommaya reservoir in 26 patients with cystic brain tumors consisting of 16 gliomas, 3 craniopharyngiomas, 3 metastatic brain tumors and 5 other and unknown pathologies, on the way of their biopsy. The entire procedure was carried out in the CT room using Leksell's CT stereotaxic system. In 24 cases with supratentorial tumors, it was at the option of the operator to take any approach such as frontal, posterior temporal and parietal approaches. Especially in 3 cases of craniopharyngioma, we inserted the tube into their cyst directly so that the ventricle should not be open to the cyst. Also in cases of a pontine glioma and a C-P angle metastatic tumor, we used retromastoid approach to the posterior fossa by making patient's heads turned about 30 to 40 deg to contralateral side of the approach, with slight flexion of the neck. Minimal bleeding occurred during operation in one case, however, it showed no clinical symptoms. Advantages of this method are as follows: Operative invasion is minimal; The surgeon can check the course of the cannula and position of the tip of Ommaya tube even at operation, and can modify it, if necessary.

  17. Hybrid approach of ventricular assist device and autologous bone marrow stem cells implantation in end-stage ischemic heart failure enhances myocardial reperfusion

    Directory of Open Access Journals (Sweden)

    Khayat Andre

    2011-01-01

    Full Text Available Abstract We challenge the hypothesis of enhanced myocardial reperfusion after implanting a left ventricular assist device together with bone marrow mononuclear stem cells in patients with end-stage ischemic cardiomyopathy. Irreversible myocardial loss observed in ischemic cardiomyopathy leads to progressive cardiac remodelling and dysfunction through a complex neurohormonal cascade. New generation assist devices promote myocardial recovery only in patients with dilated or peripartum cardiomyopathy. In the setting of diffuse myocardial ischemia not amenable to revascularization, native myocardial recovery has not been observed after implantation of an assist device as destination therapy. The hybrid approach of implanting autologous bone marrow stem cells during assist device implantation may eventually improve native cardiac function, which may be associated with a better prognosis eventually ameliorating the need for subsequent heart transplantation. The aforementioned hypothesis has to be tested with well-designed prospective multicentre studies.

  18. Basal ganglia germinoma in children with associated ipsilateral cerebral and brain stem hemiatrophy

    Energy Technology Data Exchange (ETDEWEB)

    Ozelame, Rodrigo V.; Shroff, Manohar; Wood, Bradley; Bouffet, Eric; Bartels, Ute; Drake, James M.; Hawkins, Cynthia; Blaser, Susan [Hospital for Sick Children, Department of Diagnostic Imaging, Toronto, Ontario (Canada)

    2006-04-15

    Germinoma is the most common and least-malignant intracranial germ cell tumor, usually found in the midline. Germinoma that arises in the basal ganglia, called ectopic germinoma, is a rare and well-documented entity representing 5% to 10% of all intracranial germinomas. The association of cerebral and/or brain stem atrophy with basal ganglia germinoma on CT and MRI is found in 33% of the cases. To review the literature and describe the CT and MRI findings of basal ganglia germinoma in children, known as ectopic germinoma, with associated ipsilateral cerebral and brain stem hemiatrophy. Three brain CT and six brain MRI studies performed in four children at two institutions were retrospectively reviewed. All patients were male (case 1, 14 years; case 2, 13 years; case 3, 9 years; case 4, 13 years), with pathologically proved germinoma arising in the basal ganglia, and associated ipsilateral cerebral and/or brain stem hemiatrophy on the first imaging study. It is important to note that three of these children presented with cognitive decline, psychosis and slowly progressive hemiparesis as their indication for imaging. Imaging results on initial scans were varied. In all patients, the initial study showed ipsilateral cerebral and/or brain stem hemiatrophy, representing Wallerian degeneration. All patients who underwent CT imaging presented with a hyperdense or calcified lesion in the basal ganglia on unenhanced scans. Only one of these lesions had a mass effect on the surrounding structures. In one of these patients a large, complex, heterogeneous mass appeared 15 months later. Initial MR showed focal or diffusely increased T2 signal in two cases and heterogeneous signal in the other two. (orig.)

  19. Does State Merit-Based Aid Stem Brain Drain?

    Science.gov (United States)

    Zhang, Liang; Ness, Erik C.

    2010-01-01

    In this study, the authors use college enrollment and migration data to test the brain drain hypothesis. Their results suggest that state merit scholarship programs do indeed stanch the migration of "best and brightest" students to other states. In the aggregate and on average, the implementation of state merit aid programs increases the…

  20. Stem Cells Expand Insights into Human Brain Evolution.

    Science.gov (United States)

    Dyer, Michael A

    2016-04-07

    Substantial expansion in the number of cerebral cortex neurons is thought to underlie cognitive differences between humans and other primates, although the mechanisms underlying this expansion are unclear. Otani et al. (2016) utilize PSC-derived brain organoids to study how species-specific differences in cortical progenitor proliferation may underlie cortical evolution.

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

    Science.gov (United States)

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

    2010-01-01

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

  2. Aberrant brain-stem morphometry associated with sleep disturbance in drug-naïve subjects with Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Lee JH

    2016-08-01

    Full Text Available Ji Han Lee,1 Won Sang Jung,2 Woo Hee Choi,3 Hyun Kook Lim4 1Washington University in St Louis, St Louis, MO, USA; 2Department of Radiology, 3Department of Nuclear Medicine, 4Department of Psychiatry, Saint Vincent Hospital, College of Medicine, The Catholic University of Korea, Suwon, South Korea Objective: Among patients with Alzheimer’s disease (AD, sleep disturbances are common and serious noncognitive symptoms. Previous studies of AD patients have identified deformations in the brain stem, which may play an important role in the regulation of sleep. The aim of this study was to further investigate the relationship between sleep disturbances and alterations in brain stem morphology in AD.Materials and methods: In 44 patients with AD and 40 healthy elderly controls, sleep disturbances were measured using the Neuropsychiatry Inventory sleep subscale. We employed magnetic resonance imaging-based automated segmentation tools to examine the relationship between sleep disturbances and changes in brain stem morphology.Results: Analyses of the data from AD subjects revealed significant correlations between the Neuropsychiatry Inventory sleep-subscale scores and structural alterations in the left posterior lateral region of the brain stem, as well as normalized brain stem volumes. In addition, significant group differences in posterior brain stem morphology were observed between the AD group and the control group.Conclusion: This study is the first to analyze an association between sleep disturbances and brain stem morphology in AD. In line with previous findings, this study lends support to the possibility that brain stem structural abnormalities might be important neurobiological mechanisms underlying sleep disturbances associated with AD. Further longitudinal research is needed to confirm these findings. Keywords: Alzheimer’s disease, sleep, brain stem, MRI, shape analysis

  3. Expression of androgen receptor mRNA in the brain of Gekko gecko: implications for understanding the role of androgens in controlling auditory and vocal processes.

    Science.gov (United States)

    Tang, Y Z; Piao, Y S; Zhuang, L Z; Wang, Z W

    2001-09-17

    The neuroanatomical distribution of androgen receptor (AR) mRNA-containing cells in the brain of a vocal lizard, Gekko gecko, was mapped using in situ hybridization. Particular attention was given to auditory and vocal nuclei. Within the auditory system, the cochlear nuclei, the central nucleus of the torus semicircularis, the nucleus medialis, and the medial region of the dorsal ventricular ridge contained moderate numbers of labeled neurons. Neurons labeled with the AR probe were located in many nuclei related to vocalization. Within the hindbrain, the mesencephalic nucleus of the trigeminal nerve, the vagal part of the nucleus ambiguus, and the dosal motor nucleus of the vagus nerve contained many neurons that exhibited strong expression of AR mRNA. Neurons located in the peripheral nucleus of the torus in the mesencephalon exhibited moderate levels of hybridization. Intense AR mRNA expression was also observed in neurons within two other areas that may be involved in vocalization, the medial preoptic area and the hypoglossal nucleus. The strongest mRNA signals identified in this study were found in cells of the pallium, hypothalamus, and inferior nucleus of the raphe. The expression patterns of AR mRNA in the auditory and vocal control nuclei of G. gecko suggest that neurons involved in acoustic communication in this species, and perhaps related species, are susceptible to regulation by androgens during the breeding season. The significance of these results for understanding the evolution of reptilian vocal communication is discussed.

  4. [Changes of EEG power spectrum in response to the emotional auditory stimuli in patients in acute and recovery stages of TBI (traumatic brain injury)].

    Science.gov (United States)

    2013-01-01

    We investigated variability of responses to emotionally important auditory stimulation in different groups of TBI (Traumatic Brain Injury) in acute state or recovery. The patients sampling consisted of three different groups: patients in coma or vegetative state, patients with Severe and Moderate TBI in recovery period. Subjects were stimulated with auditory stimuli containing important physiological sounds (coughing, vomiting), emotional sounds (laughing, crying), nature sounds (bird song, barking), unpleasant household sounds (nails scratching the glass), natural sounds (sea, rain, fire) and neutral sounds (white noise). The background encephalographic activity was registered during at least 7 minutes. EEG was recorded while using portable device "Entsefalan". Significant differences of power of the rhythmic activity registered during the presentation of different types of stimuli were analyzed using Mathlab and Statistica 6.0. Results showed that EEG-response to the emotional stimuli differed depending on consciousness level, stimuli type, severity of TBI. Most valuable changes in EEG spectrum power for a patient with TBI were found for unpleasant auditory stimulation. Responsiveness to the pleasant stimulation could be registered in later stages of coming out of coma than to unpleasant stimulation. Alpha-activity is reducing in patients with TBI: the alpha rhythm depression is most evident in the control group, less in group after moderate TBI, and even less in group after severe TBI. Patients in coma or vegetative state didn't show any response in rhythmic power in the frequency of alpha rhythm.

  5. Classic and novel stem cell niches in brain homeostasis and repair.

    Science.gov (United States)

    Lin, Ruihe; Iacovitti, Lorraine

    2015-12-02

    Neural stem cells (NSCs) critical for the continued production of new neurons and glia are sequestered in distinct areas of the brain called stem cell niches. Until recently, only two forebrain sites, the subventricular zone (SVZ) of the anterolateral ventricle and the subgranular zone (SGZ) of the hippocampus, have been recognized adult stem cell niches (Alvarez-Buylla and Lim, 2004; Doetsch et al., 1999a, 1999b; Doetsch, 2003a, 2003b; Lie et al., 2004; Ming and Song, 2005). Nonetheless, the last decade has been witness to a growing literature suggesting that in fact the adult brain contains stem cell niches along the entire extent of the ventricular system. These niches are capable of widespread neurogenesis and gliogenesis, particularly after injury (Barnabé-Heider et al., 2010; Carlén et al., 2009; Decimo et al., 2012; Lin et al., 2015; Lindvall and Kokaia, 2008; Robins et al., 2013) or other inductive stimuli (Bennett et al., 2009; Cunningham et al., 2012; Decimo et al., 2011; Kokoeva et al., 2007, 2005; Lee et al., 2012a, 2012b; Migaud et al., 2010; Pencea et al., 2001b; Sanin et al., 2013; Suh et al., 2007; Sundholm-Peters et al., 2004; Xu et al., 2005; Zhang et al., 2007). This review focuses on the role of these novel and classic brain niches in maintaining adult neurogenesis and gliogenesis in response to normal physiological and injury-related pathological cues. This article is part of a Special Issue entitled SI: Neuroprotection.

  6. Production Process for Stem Cell Based Therapeutic Implants: Expansion of the Production Cell Line and Cultivation of Encapsulated Cells

    Science.gov (United States)

    Weber, C.; Pohl, S.; Poertner, R.; Pino-Grace, Pablo; Freimark, D.; Wallrapp, C.; Geigle, P.; Czermak, P.

    Cell based therapy promises the treatment of many diseases like diabetes mellitus, Parkinson disease or stroke. Microencapsulation of the cells protects them against host-vs-graft reactions and thus enables the usage of allogenic cell lines for the manufacturing of cell therapeutic implants. The production process of such implants consists mainly of the three steps expansion of the cells, encapsulation of the cells, and cultivation of the encapsulated cells in order to increase their vitality and thus quality. This chapter deals with the development of fixed-bed bioreactor-based cultivation procedures used in the first and third step of production. The bioreactor system for the expansion of the stem cell line (hMSC-TERT) is based on non-porous glass spheres, which support cell growth and harvesting with high yield and vitality. The cultivation process for the spherical cell based implants leads to an increase of vitality and additionally enables the application of a medium-based differentiation protocol.

  7. Listening to Brain Microcircuits for Interfacing With External World—Progress in Wireless Implantable Microelectronic Neuroengineering Devices

    Science.gov (United States)

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

    2011-01-01

    Acquiring neural signals at high spatial and temporal resolution directly from brain microcircuits and decoding their activity to interpret commands and/or prior planning activity, such as motion of an arm or a leg, is a prime goal of modern neurotechnology. Its practical aims include assistive devices for subjects whose normal neural information pathways are not functioning due to physical damage or disease. On the fundamental side, researchers are striving to decipher the code of multiple neural microcircuits which collectively make up nature’s amazing computing machine, the brain. By implanting biocompatible neural sensor probes directly into the brain, in the form of microelectrode arrays, it is now possible to extract information from interacting populations of neural cells with spatial and temporal resolution at the single cell level. With parallel advances in application of statistical and mathematical techniques tools for deciphering the neural code, extracted populations or correlated neurons, significant understanding has been achieved of those brain commands that control, e.g., the motion of an arm in a primate (monkey or a human subject). These developments are accelerating the work on neural prosthetics where brain derived signals may be employed to bypass, e.g., an injured spinal cord. One key element in achieving the goals for practical and versatile neural prostheses is the development of fully implantable wireless microelectronic “brain-interfaces” within the body, a point of special emphasis of this paper. PMID:21654935

  8. Neurogenesis in the brain stem of the rabbit: an autoradiographic study

    Energy Technology Data Exchange (ETDEWEB)

    Oblinger, M.M.; Das, G.D.

    1981-03-20

    With the aid of (/sup 3/H)-thymidine autoradiography, neurogenesis was documented in the nuclear groups of the medulla oblongata, pons, and mid-brain, as well as in the brain stem reticular formation of the rabbit. Following single injections of (/sup 3/H)-thymidine, counts were taken of intensely labeled neurons within the nuclei of the functional columns related to the cranial nerves, nuclei of several other functional classifications, and nuclei that did not fit into a functional category. In the brain stem as a whole, neurogenesis was found to occur between days 10.0 and 18.5 of gestation: however, the majority of nuclei studied contained intensely neurons only between days 12.0 and 15.0. Only in the pontine nucleus and the tectum were intensely labeled cells observed as late as day 18.5. Directional gradients of histogenesis were often observed within, as well as between, various nuclei. Within the nuclear columns related to the cranial nerves, a clear mediolateral spread of neurogenesis was observable such that nuclei of the motor columns reached a peak in neurogenesis before those in the sensory columns. Likewise, a mediolateral proliferation pattern was seen in the brain stem reticular formation. Other individual directional gradients were discernible; however, in the brain stem as a whole, distinct overall gradients were not observable. In many individual nuclei, gradients in neuron size were observed such that large neurons preferentially arose prior to smaller neurons. Information pertaining to gradients in neurogenesis, as well as to relationships among functionally related nuclei, are discussed.

  9. Auditory Processing Disorder (For Parents)

    Science.gov (United States)

    ... CAPD often have trouble maintaining attention, although health, motivation, and attitude also can play a role. Auditory ... programs. Several computer-assisted programs are geared toward children with APD. They mainly help the brain do ...

  10. Neural stem cell transplantation with Nogo-66 receptor gene silencing to treat severe traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Dong Wang; Jianjun Zhang; Jingjian Ma; Yuan Mu; Yinghui Zhuang

    2011-01-01

    Inhibition of neurite growth, which is mediated by the Nogo-66 receptor (NgR), affects nerve regeneration following neural stem cell (NSC) transplantation. The present study utilized RNA interference to silence NgR gene expression in NSCs, which were subsequently transplanted into rats with traumatic brain injury. Following transplantation of NSCs transfected with small interfering RNA,typical neural cell-like morphology was detected in injured brain tissues, and was accompanied by absence of brain tissue cavity, increased growth-associated protein 43 mRNA and protein expression,and improved neurological function compared with NSC transplantation alone. Results demonstrated that NSC transplantation with silenced NgR gene promoted functional recovery following brain injury.

  11. Derivation of blood-brain barrier endothelial cells from human pluripotent stem cells.

    Science.gov (United States)

    Lippmann, Ethan S; Azarin, Samira M; Kay, Jennifer E; Nessler, Randy A; Wilson, Hannah K; Al-Ahmad, Abraham; Palecek, Sean P; Shusta, Eric V

    2012-08-01

    The blood-brain barrier (BBB) is crucial to the health of the brain and is often compromised in neurological disease. Moreover, because of its barrier properties, this endothelial interface restricts uptake of neurotherapeutics. Thus, a renewable source of human BBB endothelium could spur brain research and pharmaceutical development. Here we show that endothelial cells derived from human pluripotent stem cells (hPSCs) acquire BBB properties when co-differentiated with neural cells that provide relevant cues, including those involved in Wnt/β-catenin signaling. The resulting endothelial cells have many BBB attributes, including well-organized tight junctions, appropriate expression of nutrient transporters and polarized efflux transporter activity. Notably, they respond to astrocytes, acquiring substantial barrier properties as measured by transendothelial electrical resistance (1,450 ± 140 Ω cm2), and they possess molecular permeability that correlates well with in vivo rodent blood-brain transfer coefficients.

  12. TGFβ lengthens the G1 phase of stem cells in aged mouse brain.

    Science.gov (United States)

    Daynac, Mathieu; Pineda, Jose R; Chicheportiche, Alexandra; Gauthier, Laurent R; Morizur, Lise; Boussin, François D; Mouthon, Marc-André

    2014-12-01

    Neurogenesis decreases during aging causing a progressive cognitive decline but it is still controversial whether proliferation defects in neurogenic niches result from a loss of neural stem cells or from an impairment of their progression through the cell cycle. Using an accurate fluorescence-activated cell sorting technique, we show that the pool of neural stem cells is maintained in the subventricular zone of middle-aged mice while they have a reduced proliferative potential eventually leading to the subsequent decrease of their progeny. In addition, we demonstrate that the G1 phase is lengthened during aging specifically in activated stem cells, but not in transit-amplifying cells, and directly impacts on neurogenesis. Finally, we report that inhibition of TGFβ signaling restores cell cycle progression defects in stem cells. Our data highlight the significance of cell cycle dysregulation in stem cells in the aged brain and provide an attractive foundation for the development of anti-TGFβ regenerative therapies based on stimulating endogenous neural stem cells.

  13. Moving on time: brain network for auditory-motor synchronization is modulated by rhythm complexity and musical training.

    Science.gov (United States)

    Chen, Joyce L; Penhune, Virginia B; Zatorre, Robert J

    2008-02-01

    Much is known about the motor system and its role in simple movement execution. However, little is understood about the neural systems underlying auditory-motor integration in the context of musical rhythm, or the enhanced ability of musicians to execute precisely timed sequences. Using functional magnetic resonance imaging, we investigated how performance and neural activity were modulated as musicians and nonmusicians tapped in synchrony with progressively more complex and less metrically structured auditory rhythms. A functionally connected network was implicated in extracting higher-order features of a rhythm's temporal structure, with the dorsal premotor cortex mediating these auditory-motor interactions. In contrast to past studies, musicians recruited the prefrontal cortex to a greater degree than nonmusicians, whereas secondary motor regions were recruited to the same extent. We argue that the superior ability of musicians to deconstruct and organize a rhythm's temporal structure relates to the greater involvement of the prefrontal cortex mediating working memory.

  14. Murine cytomegalovirus infection of neural stem cells alters neurogenesis in the developing brain.

    Directory of Open Access Journals (Sweden)

    Manohar B Mutnal

    Full Text Available BACKGROUND: Congenital cytomegalovirus (CMV brain infection causes serious neuro-developmental sequelae including: mental retardation, cerebral palsy, and sensorineural hearing loss. But, the mechanisms of injury and pathogenesis to the fetal brain are not completely understood. The present study addresses potential pathogenic mechanisms by which this virus injures the CNS using a neonatal mouse model that mirrors congenital brain infection. This investigation focused on, analysis of cell types infected with mouse cytomegalovirus (MCMV and the pattern of injury to the developing brain. METHODOLOGY/PRINCIPAL FINDINGS: We used our MCMV infection model and a multi-color flow cytometry approach to quantify the effect of viral infection on the developing brain, identifying specific target cells and the consequent effect on neurogenesis. In this study, we show that neural stem cells (NSCs and neuronal precursor cells are the principal target cells for MCMV in the developing brain. In addition, viral infection was demonstrated to cause a loss of NSCs expressing CD133 and nestin. We also showed that infection of neonates leads to subsequent abnormal brain development as indicated by loss of CD24(hi cells that incorporated BrdU. This neonatal brain infection was also associated with altered expression of Oct4, a multipotency marker; as well as down regulation of the neurotrophins BDNF and NT3, which are essential to regulate the birth and differentiation of neurons during normal brain development. Finally, we report decreased expression of doublecortin, a marker to identify young neurons, following viral brain infection. CONCLUSIONS: MCMV brain infection of newborn mice causes significant loss of NSCs, decreased proliferation of neuronal precursor cells, and marked loss of young neurons.

  15. In situ monitoring of brain tissue reaction of chronically implanted electrodes with an optical coherence tomography fiber system

    Science.gov (United States)

    Xie, Yijing; Hassler, Christina; Stieglitz, Thomas; Seifert, Andreas; Hofmann, Ulrich G.

    2014-03-01

    Neural microelectrodes are well established tools for delivering therapeutic electrical pulses, and recording neural electrophysiological signals. However, long term implanted neural probes often become functionally impaired by tissue encapsulation. At present, analyzing this immune reaction is only feasible with post-mortem histology; currently no means for specific in vivo monitoring exist and most applicable imaging modalities provide no sufficient resolution for a cellular measurement in deep brain regions. Optical coherence tomography (OCT) is a well developed imaging modality, providing cellular resolution and up to 1.2 mm imaging depth in brain tissue. Further more, a fiber based spectral domain OCT was shown to be capable of minimally invasive brain intervention. In the present study, we propose to use a fiber based spectral domain OCT to monitor the the progression of the tissue's immune response and scar encapsulation of microprobes in a rat animal model. We developed an integrated OCT fiber catheter consisting of an implantable ferrule based fiber cannula and a fiber patch cable. The fiber cannula was 18.5 mm long, including a 10.5 mm ceramic ferrule and a 8.0 mm long, 125 μm single mode fiber. A mating sleeve was used to fix and connect the fiber cannula to the OCT fiber cable. Light attenuation between the OCT fiber cable and the fiber cannula through the mating sleeve was measured and minimized. The fiber cannula was implanted in rat brain together with a microelectrode in sight used as a foreign body to induce the brain tissue immune reaction. Preliminary data showed a significant enhancement of the OCT backscattering signal during the brain tissue scarring process, while the OCT signal of the flexible microelectrode was getting weaker consequentially.

  16. From pluripotent stem cells to multifunctional cordocytic phenotypes in the human brain: an ultrastructural study.

    Science.gov (United States)

    Pais, Viorel; Danaila, Leon; Pais, Emil

    2012-08-01

    Light microscopy and transmission electron microscopy were used to investigate surgical cases in a variety of pathological conditions (thromboses, tumors, cerebrovascular malformations, Moyamoya disease) to identify and characterize different phenotypes belonging to a new interstitial cell recently described ultrastructurally in the brain and here named "cordocyte." Also, this work is an attempt to identify and characterize precursor/stem cells for cordocytic lineage in the perivascular areas, within perivascular nerves and pia mater (now considered a cordocytic-vascular tissue). Unexpected relationships and functions emerge from observations concerning these phenotypes, almost ubiquitous, but not yet fully studied in the brain.

  17. Delayed radiation-induced necrosis of the brain stem; A case report

    Energy Technology Data Exchange (ETDEWEB)

    Yukawa, Osamu; Kodama, Yasunori; Kyoda, Jun; Yuki, Kiyoshi; Taniguchi, Eiji; Katayama, Shoichi; Hiroi, Tadashi (National Kure Hospital, Hiroshima (Japan)); Uozumi, Toru

    1993-03-01

    A 46-year-old man had surgery for a mixed glioma of the frontotemporal lobe. Postoperatively he received 50 Gy of irradiation. Sixteen months later he developed left hemiparesis and left facial palsy. MRI revealed lesion brain stem and basal ganglia. Despite chemotherapy and an additional 50 Gy dose, the patient deteriorated. Autopsy revealed a wide spread radiation-induced necrosis in the right cerebral hemisphere, midbrain and pons. In radiation therapy, great care must be taken to protect the normal brain tissue. (author).

  18. Long-term meditation is associated with increased gray matter density in the brain stem

    DEFF Research Database (Denmark)

    Vestergaard-Poulsen, Peter; Beek, Martijn van; Skewes, Joshua

    2009-01-01

    Extensive practice involving sustained attention can lead to changes in brain structure. Here, we report evidence of structural differences in the lower brainstem of participants engaged in the long-term practice of meditation. Using magnetic resonance imaging, we observed higher gray matter...... density in lower brain stem regions of experienced meditators compared with age-matched nonmeditators. Our findings show that long-term practitioners of meditation have structural differences in brainstem regions concerned with cardiorespiratory control. This could account for some...... of the cardiorespiratory parasympathetic effects and traits, as well as the cognitive, emotional, and immunoreactive impact reported in several studies of different meditation practices....

  19. Cochlear Implant

    Directory of Open Access Journals (Sweden)

    Mehrnaz Karimi

    1992-04-01

    Full Text Available People with profound hearing loss are not able to use some kinds of conventional amplifiers due to the nature of their loss . In these people, hearing sense is stimulated only when the auditory nerve is activated via electrical stimulation. This stimulation is possible through cochlear implant. In fact, for the deaf people who have good mental health and can not use surgical and medical treatment and also can not benefit from air and bone conduction hearing aids, this device is used if they have normal central auditory system. The basic parts of the device included: Microphone, speech processor, transmitter, stimulator and receiver, and electrode array.

  20. Endovascular treatment of brain-stem arteriovenous malformations: safety and efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H.M.; Wang, Y.H.; Chen, Y.F.; Huang, K.M. [Department of Medical Imaging, National Taiwan University Hospital, 7 Chung-Shan South Road, 10016, Taipei (Taiwan); Tu, Y.K. [Division of Neurosurgery, Department of Surgery, National Taiwan University Hospital, 7 Chung-Shan South Road, 1001, Taipei (Taiwan)

    2003-09-01

    Our purpose was to evaluate the safety and efficacy of endovascular treatment of brain-stem arteriovenous malformations (AVMs), reviewing six cases managed in the last 5 years. There were four patients who presented with bleeding, one with a progressive neurological deficit and one with obstructive hydrocephalus. Of the six patients, one showed 100%, one 90%, two 75% and two about 50% angiographic obliteration of the AVM after embolisation; the volume decreased about 75% on average. Five patients had a good outcome and one an acceptable outcome, with a mild postprocedure neurological deficit; none had further bleeding during midterm follow-up. Endovascular management of a brain-stem AVM may be an alternative to treatment such as radiosurgery and microsurgery in selected cases. It may be not as risky as previously thought. Embolisation can reduce the size of the AVM and possibly make it more treatable by radiosurgery and decrease the possibility of radiation injury. (orig.)

  1. Microinjection of membrane-impermeable molecules into single neural stem cells in brain tissue.

    Science.gov (United States)

    Wong, Fong Kuan; Haffner, Christiane; Huttner, Wieland B; Taverna, Elena

    2014-05-01

    This microinjection protocol allows the manipulation and tracking of neural stem and progenitor cells in tissue at single-cell resolution. We demonstrate how to apply microinjection to organotypic brain slices obtained from mice and ferrets; however, our technique is not limited to mouse and ferret embryos, but provides a means of introducing a wide variety of membrane-impermeable molecules (e.g., nucleic acids, proteins, hydrophilic compounds) into neural stem and progenitor cells of any developing mammalian brain. Microinjection experiments are conducted by using a phase-contrast microscope equipped with epifluorescence, a transjector and a micromanipulator. The procedure normally takes ∼2 h for an experienced researcher, and the entire protocol, including tissue processing, can be performed within 1 week. Thus, microinjection is a unique and versatile method for changing and tracking the fate of a cell in organotypic slice culture.

  2. Robotics, Stem Cells and Brain Computer Interfaces in Rehabilitation and Recovery from Stroke; Updates and Advances

    Science.gov (United States)

    Boninger, Michael L; Wechsler, Lawrence R.; Stein, Joel

    2014-01-01

    Objective To describe the current state and latest advances in robotics, stem cells, and brain computer interfaces in rehabilitation and recovery for stroke. Design The authors of this summary recently reviewed this work as part of a national presentation. The paper represents the information included in each area. Results Each area has seen great advances and challenges as products move to market and experiments are ongoing. Conclusion Robotics, stem cells, and brain computer interfaces all have tremendous potential to reduce disability and lead to better outcomes for patients with stroke. Continued research and investment will be needed as the field moves forward. With this investment, the potential for recovery of function is likely substantial PMID:25313662

  3. Evaluation of normal and pathologic appearance in skull base and brain stem with metrizamide CT cisternography

    Energy Technology Data Exchange (ETDEWEB)

    Morimura, Tatsuo; Nakano, Masaru; Maeda, Yukio; Yokota, Masayuki; Kokubu, Kiyokazu; Shimada, Tatsuji (Hyogo College of Medicine (Japan))

    1985-02-01

    Metrizamide CT cisternography was performed in accordance with prone 60/sup 0/ head-down method, to study the normal anatomy of the skull base and brain stem. Cases of empty sellae, Rathke's cleft cyst, mucocele trigeminal neurinoma, pons glioma, acoustic neurinoma and jugular foramen tumor were studied together. As side effects of MCTC there were headache, vomiting and appearance of slow waves on EEG, but no convulsion. Transient encephalopathy was noted when 250 mgI/ml, 12 ml, was used. Using MCTC, it is possible to identify the vertebral artery, posterior inferior cerebellar artery, basillar artery, vessels forming Willis ring as well as II, III, V, VII and VIII cranial nerves. Further, by measuring the brain stem parts on various levels, it may become possible to detect early changes of degenerative disease.

  4. Mitochondrial aspartyl-tRNA synthetase deficiency causes leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation.

    NARCIS (Netherlands)

    Scheper, G.C.; Klok, T. van der; Andel, R.J. van; Berkel, C.G. van; Sissler, M.; Smet, J.; Muravina, T.I.; Serkov, S.V.; Uziel, G.; Bugiani, M.; Schiffmann, R.; Krageloh-Mann, I.; Smeitink, J.A.M.; Florentz, C.; Coster, R. van; Pronk, J.C.; Knaap, M.S. van der

    2007-01-01

    Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation (LBSL) has recently been defined based on a highly characteristic constellation of abnormalities observed by magnetic resonance imaging and spectroscopy. LBSL is an autosomal recessive disease, most often manifesti

  5. Therapeutics with SPION-labeled stem cells for the main diseases related to brain aging: a systematic review

    Science.gov (United States)

    Alvarim, Larissa T; Nucci, Leopoldo P; Mamani, Javier B; Marti, Luciana C; Aguiar, Marina F; Silva, Helio R; Silva, Gisele S; Nucci-da-Silva, Mariana P; DelBel, Elaine A; Gamarra, Lionel F

    2014-01-01

    The increase in clinical trials assessing the efficacy of cell therapy for structural and functional regeneration of the nervous system in diseases related to the aging brain is well known. However, the results are inconclusive as to the best cell type to be used or the best methodology for the homing of these stem cells. This systematic review analyzed published data on SPION (superparamagnetic iron oxide nanoparticle)-labeled stem cells as a therapy for brain diseases, such as ischemic stroke, Parkinson’s disease, amyotrophic lateral sclerosis, and dementia. This review highlights the therapeutic role of stem cells in reversing the aging process and the pathophysiology of brain aging, as well as emphasizing nanotechnology as an important tool to monitor stem cell migration in affected regions of the brain. PMID:25143726

  6. Therapeutics with SPION-labeled stem cells for the main diseases related to brain aging: a systematic review.

    Science.gov (United States)

    Alvarim, Larissa T; Nucci, Leopoldo P; Mamani, Javier B; Marti, Luciana C; Aguiar, Marina F; Silva, Helio R; Silva, Gisele S; Nucci-da-Silva, Mariana P; DelBel, Elaine A; Gamarra, Lionel F

    2014-01-01

    The increase in clinical trials assessing the efficacy of cell therapy for structural and functional regeneration of the nervous system in diseases related to the aging brain is well known. However, the results are inconclusive as to the best cell type to be used or the best methodology for the homing of these stem cells. This systematic review analyzed published data on SPION (superparamagnetic iron oxide nanoparticle)-labeled stem cells as a therapy for brain diseases, such as ischemic stroke, Parkinson's disease, amyotrophic lateral sclerosis, and dementia. This review highlights the therapeutic role of stem cells in reversing the aging process and the pathophysiology of brain aging, as well as emphasizing nanotechnology as an important tool to monitor stem cell migration in affected regions of the brain.

  7. Effects of the pyrethroid insecticide, deltamethrin, on respiratory modulated hypoglossal motoneurons in a brain stem slice from newborn mice

    DEFF Research Database (Denmark)

    Rekling, J C; Theophilidis, G

    1995-01-01

    We have studied the action of deltamethrin on respiratory modulated hypoglossal motoneurons in a brain stem slice from newborn mice. Deltamethrin depolarized the hypoglossal motoneurons, increased the background synaptic noise and reduced the frequency and amplitude of current elicited action...

  8. Influence of the extracellular matrix on endogenous and transplanted stem cells after brain damage

    Directory of Open Access Journals (Sweden)

    Lars eRoll

    2014-08-01

    Full Text Available The limited regeneration capacity of the adult central nervous system requires strategies to improve recovery of patients. In this context, the interaction of endogenous as well as transplanted stem cells with their environment is crucial. An understanding of the molecular mechanisms could help to improve regeneration by targeted manipulation.In the course of reactive gliosis, astrocytes upregulate Glial fibrillary acidic protein (GFAP and start, in many cases, to proliferate. Beside GFAP, subpopulations of these astroglial cells coexpress neural progenitor markers like Nestin. Although cells express these markers, the proportion of cells that eventually give rise to neurons is limited in many cases in vivo compared to the situation in vitro. In the first section, we present the characteristics of endogenous progenitor-like cells and discuss the differences in their neurogenic potential in vitro and in vivo.As the environment plays an important role for survival, proliferation, migration, and other processes, the second section of the review describes changes in the extracellular matrix (ECM, a complex network that contains numerous signaling molecules. It appears that signals in the damaged central nervous system lead to an activation and de-differentiation of astrocytes, but do not effectively promote neuronal differentiation of these cells. Factors that influence stem cells during development are upregulated in the damaged brain as part of an environment resembling a stem cell niche. We give a general description of the ECM composition, with focus on stem cell-associated factors like the glycoprotein Tenascin-C.Stem cell transplantation is considered as potential treatment strategy. Interaction of transplanted stem cells with the host environment is critical for the outcome of stem cell-based therapies. Possible mechanisms involving the ECM by which transplanted stem cells might improve recovery are discussed in the last section.

  9. Human Umbilical Cord Blood Stem Cells: Rational for Use as a Neuroprotectant in Ischemic Brain Disease

    Directory of Open Access Journals (Sweden)

    Hadar Arien-Zakay

    2010-09-01

    Full Text Available The use of stem cells for reparative medicine was first proposed more than three decades ago. Hematopoietic stem cells from bone marrow, peripheral blood and human umbilical cord blood (CB have gained major use for treatment of hematological indications. CB, however, is also a source of cells capable of differentiating into various non-hematopoietic cell types, including neural cells. Several animal model reports have shown that CB cells may be used for treatment of neurological injuries. This review summarizes the information available on the origin of CB-derived neuronal cells and the mechanisms proposed to explain their action. The potential use of stem/progenitor cells for treatment of ischemic brain injuries is discussed. Issues that remain to be resolved at the present stage of preclinical trials are addressed.

  10. "Optical communication with brain cells by means of an implanted duplex micro-device with optogenetics and Ca(2+) fluoroimaging".

    Science.gov (United States)

    Kobayashi, Takuma; Haruta, Makito; Sasagawa, Kiyotaka; Matsumata, Miho; Eizumi, Kawori; Kitsumoto, Chikara; Motoyama, Mayumi; Maezawa, Yasuyo; Ohta, Yasumi; Noda, Toshihiko; Tokuda, Takashi; Ishikawa, Yasuyuki; Ohta, Jun

    2016-02-16

    To better understand the brain function based on neural activity, a minimally invasive analysis technology in a freely moving animal is necessary. Such technology would provide new knowledge in neuroscience and contribute to regenerative medical techniques and prosthetics care. An application that combines optogenetics for voluntarily stimulating nerves, imaging to visualize neural activity, and a wearable micro-instrument for implantation into the brain could meet the abovementioned demand. To this end, a micro-device that can be applied to the brain less invasively and a system for controlling the device has been newly developed in this study. Since the novel implantable device has dual LEDs and a CMOS image sensor, photostimulation and fluorescence imaging can be performed simultaneously. The device enables bidirectional communication with the brain by means of light. In the present study, the device was evaluated in an in vitro experiment using a new on-chip 3D neuroculture with an extracellular matrix gel and an in vivo experiment involving regenerative medical transplantation and gene delivery to the brain by using both photosensitive channel and fluorescent Ca(2+) indicator. The device succeeded in activating cells locally by selective photostimulation, and the physiological Ca(2+) dynamics of neural cells were visualized simultaneously by fluorescence imaging.

  11. Combined Striatum, Brain Stem, and Optic Nerve Involvement due to Mycoplasma pneumoniae in an Ambulatory Child

    Directory of Open Access Journals (Sweden)

    Jin-Won Bae

    2011-05-01

    Full Text Available In children, Mycoplasma pneumoniae encephalitis has been characterized by acute onset of an encephalopathy associated with extrapyramidal symptoms and symmetric basal ganglia with or without brain stem involvement on magnetic resonance imaging. Our case, showing unilateral optic neuritis, ophthalmoplegia, no extrapyramidal symptoms, and typical striatal involvement on magnetic resonance imaging, broadens the spectrum of varying clinical manifestations of childhood M. pneumoniae-associated encephalopathy.

  12. The Regenerative Response of Endogenous Neural Stem/Progenitor Cells to Traumatic Brain Injury

    Science.gov (United States)

    2014-06-09

    neural stem cells in the adjacent SVZ, the largest germinal zone in the mammalian CNS. Ex vivo and in vivo DTI were combined with post-imaging...faults accrued over 50 steps was counted for each hind limb. Controlled Cortical Impact (CCI), which involves craniotomy and impact onto the dura...the subventricular zone (SVZ), a major germinal zone in the adult brain, have potential repair capacity that is not well understood relative to the

  13. [Trismus, trigeminal motor dyssynergy with brain stem lesions (author's transl)].

    Science.gov (United States)

    Jelasic, F; Freitag, V

    1975-08-01

    Paradox activity of masticatory muscles was observed clinically and electromyographically in 4 patients with brain steem lesions who had trismus. There was no activity in the elevators of the jaw on the side affected during voluntary biting, as if the muscles were paralyzed. There was strong activity of the elevators on the side of the trismus on opening the mouth, inactivity on the unaffected side, or inverse activity appeared on both sides. In view of the trigeminal anesthesia on the side of paradox activation, and the absence of pyramidal signs, a stretch reflex mechanism and abolition of inhibition can not be the only basis for these phenomena; so, a disturbance of bilateral synergism, in the sense of an internuclear lesion, is postulated. In one case of motor and sensory paralysis after the extirpation of a meningioma of the cerebellopontine angle, intensive paradox activity was observed, without trismus.

  14. VEGF-mediated angiogenesis stimulates neural stem cell proliferation and differentiation in the premature brain

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jinqiao, E-mail: jinqiao1977@163.com [Institute of Pediatrics, Children' s Hospital of Fudan University (China); Sha, Bin [Department of Neonatology, Children' s Hospital of Fudan University, 399 Wanyuan Road, Shanghai 201102 (China); Zhou, Wenhao, E-mail: zhou_wenhao@yahoo.com.cn [Department of Neonatology, Children' s Hospital of Fudan University, 399 Wanyuan Road, Shanghai 201102 (China); Yang, Yi [Institute of Pediatrics, Children' s Hospital of Fudan University (China)

    2010-03-26

    This study investigated the effects of angiogenesis on the proliferation and differentiation of neural stem cells in the premature brain. We observed the changes in neurogenesis that followed the stimulation and inhibition of angiogenesis by altering vascular endothelial growth factor (VEGF) expression in a 3-day-old rat model. VEGF expression was overexpressed by adenovirus transfection and down-regulated by siRNA interference. Using immunofluorescence assays, Western blot analysis, and real-time PCR methods, we observed angiogenesis and the proliferation and differentiation of neural stem cells. Immunofluorescence assays showed that the number of vWF-positive areas peaked at day 7, and they were highest in the VEGF up-regulation group and lowest in the VEGF down-regulation group at every time point. The number of neural stem cells, neurons, astrocytes, and oligodendrocytes in the subventricular zone gradually increased over time in the VEGF up-regulation group. Among the three groups, the number of these cells was highest in the VEGF up-regulation group and lowest in the VEGF down-regulation group at the same time point. Western blot analysis and real-time PCR confirmed these results. These data suggest that angiogenesis may stimulate the proliferation of neural stem cells and differentiation into neurons, astrocytes, and oligodendrocytes in the premature brain.

  15. Brain stem global gene expression profiles in human spina bifida embryos

    Institute of Scientific and Technical Information of China (English)

    Hong Zhao; Xiang Li; Wan-I Lie; Quanren He; Ting Zhang; Xiaoying Zheng; Ran Zhou; Jun Xie

    2011-01-01

    Environmental and genetic factors influence the occurrence of neural tube defects, such as spina bifida.Specific disease expression patterns will help to elucidate the pathogenesis of disease.However, results obtained from animal models, which often exhibit organism specificity, do not fully explain the mechanisms of human spina bifida onset.In the present study, three embryos with a gestational age of approximately 17 weeks and a confirmed diagnosis of spina bifida, as well as 3 age-matched normal embryos, were obtained from abortions.Fetal brain stem tissues were dissected for RNA isolation, and microarray analyses were conducted to examine profiles of gene expression in brain stems of spina bifida and normal embryos using Affymetrix HG-U1 33A 2.0 GeneChip arrays.Of the 14 500 gene transcripts examined, a total of 182 genes exhibited at least 2.5-fold change in expression, including 140 upregulated and 42 downregulated genes.These genes were placed into 19 main functional categories according to the Gene Ontology Consortium database for biological functions.Of the 182 altered genes, approximately 50% were involved in cellular apoptosis, growth, adhesion, cell cycle, stress, DNA replication and repair, signal transduction, nervous system development, oxidoreduction, immune responses, and regulation of gene transcription.Gene expression in multiple biological pathways was altered in the brain stem of human spina bifida embryos.

  16. Application of Hydrogen Technologies for Increasing the Operating Characteristic of Stem of Hip Implant Made of Titanium Alloy, Procured By Mold Castings

    Directory of Open Access Journals (Sweden)

    Skvortsova SV

    2016-11-01

    Full Text Available This work deals with the possibility of using the thermo hydrogen technology in the process of manufacturing the stem of hip implant made of titanium alloy, procured by mold castings. The influence of modes of thermo hydrogen processing on the transformation of the cast structure and mechanical properties of mold castings is analyzed in this work. It is shown that the use of thermo hydrogen processing ensures good physical and chemical contact and lets substantially increase the adhesion strength of Osseo integrating porous coating made of unalloyed titanium with titanium alloy VT6 (Ti-6-4 surface of the stem of hip implant. It identifies the elements of the processing technology of the implant elements, allowing to obtain products correspond to the international standard is identified in the work.

  17. COCHLEAR IMPLANTATION: MY EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Shankar

    2015-12-01

    Full Text Available Cochlear implant is a small, surgically implanted complex electronic device that can help to provide a sense of sound to a person with severe to profound sensorineural hearing loss. This type of hearing loss, typically involves damage to hair cells in the cochlea, as a result sound cannot reach the auditory nerve which usually receives information from hair cells. A cochlear implant skips the damaged hair cells and to stimulate the auditory nerve directly. An implant does not restore normal hearing, instead it can give a deaf person a useful representation of sounds in the environment and help him or her to understand speech. I am here presenting this article in relation to the indications, intraoperative and postoperative complications of cochlear implantation in our institute since January 2013. Children who receive implants at earlier age, outperform their peers who are implanted at a later age. This is reflected in all the areas of speech and language development.

  18. 语前聋患者人工耳蜗植入术后听觉言语康复相关影响因素的研究%Research on the Influencing Factors of Auditory and Speech Rehabilitation Outcomes of Prelingually Deaf Patients with Cochlear Implants

    Institute of Scientific and Technical Information of China (English)

    张斯斯; 林有辉; 张榕; 叶胜难

    2013-01-01

    目的探讨语前聋人工耳蜗植入患者的听觉言语康复效果及其相关影响因素。方法对159例人工耳蜗植入患者家长和康复教师进行调查随访。根据听觉行为分级标准(Categories of Auditory Performance,CAP)和言语可懂度分级标准(Speech Intelligibility Rating,SIR),对患者的听觉能力和言语能力进行分级评估。用组内单因素秩和检验和多因素Logistic回归分析CAP和SIR分级结果与性别、惯用手、内耳发育、颅脑影像学情况、术前助听器使用、术前语训、植入耳侧、植入电极类型、植入年龄、植入后时间、术后语言环境、术后康复模式、家庭经济状况等13个因素的关系。结果单因素分析结果显示,不同的术前助听器使用情况、术前语训、植入后时间、家庭经济状况组间CAP分级结果有显著性差异(P值均<0.05);不同的植入耳侧、植入后时间、家庭经济状况组间SIR分级结果有显著性差异(P值均<0.05)。多因素Logistic回归分析结果显示,植入后时间、家庭经济状况与CAP、SIR分级结果均有显著相关。结论植入后时间、家庭经济状况对人工耳蜗植入术后患者的听觉言语康复效果起决定性的作用。%Objective To explore the auditory and speech rehabilitation outcomes of prelingually hearing-impaired patients with cochlear implants and the related influencing factors. Methods One hundred fifty-nine cochlear implantees were recruited in this study.The parents or teachers were interviewed to assess the auditory and speech abilities of the subjects using Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR). The relationships were investigated between auditory and speech rehabilitation outcomes represented by CAP/SIR results and 13 possible influencing factors including gender, handedness, inner ear malformations, brain abnormalities, hearing aid use, language training before

  19. Therapeutic Potential of Umbilical Cord Blood Stem Cells on Brain Damage of a Model of Stroke

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Nikravesh

    2011-11-01

    Full Text Available Introduction: Human cord blood-derived stem cells are a rich source of stem cells as well as precursors. With regard to the researchers have focused on the therapeutic potential of stem cell in the neurological disease such as stroke, the aim of this study was the investiga-tion of the therapeutic effects of human cord blood-derived stem cells in cerebral ischemia on rat. Methods: This study was carried out on young rats. Firstly, to create a laboratory model of ischemic stroke, carotid artery of animals was occluded for 30 minutes. Then, umbilical cord blood cells were isolated and labeled using bromodeoxyuridine and 2×105 cells were injected into the experimental group via the tail vein. Rats with hypoxic condi-tions were used as a sham group. A group of animals did not receive any injection or sur-geries were used as a control. Results: Obtained results were evaluated based on behavior-al responses and immunohistochemistry, with emphasis on areas of putamen and caudate nucleus in the control, sham and experimental groups. Our results indicated that behavioral recovery was observed in the experimental group compared to the either the sham or the control group. However, histological studies demonstrated a low percent of tissue injury in the experimental group in comparison with the sham group. Conclusion: Stem cell trans-plantation is beneficial for the brain tissue reparation after hypoxic ischemic cell death.

  20. Intravascular ultrasound-guided stenting of left main stem dissection after medtronic corevalve implantation

    NARCIS (Netherlands)

    N.M. van Mieghem (Nicolas); P.P.T. de Jaegere (Peter)

    2013-01-01

    textabstractTranscatheter aortic valve implantation (TAVI) implies the introduction, positioning, and deployment of a stented bioprosthesis in the (calcified) native aortic valve. We report an at first glance uneventful TAVI with the Medtronic Corevalve System, which was followed by transient electr

  1. Low accuracy of stem implantation in THR using the CASPAR-system: anteversion measurements in 10 hips.

    Science.gov (United States)

    Mazoochian, Farhad; Pellengahr, Christoph; Huber, Armin; Kircher, Jörn; Refior, Hans Jürgen; Jansson, Volkmar

    2004-06-01

    We studied 10 patients by means of pre- and postoperative CT who underwent computer-assisted total hip replacement using the CASPAR-system (OrthoMaquet GmbH, Rastatt, Germany). The anteversion angles of the stem and translational deviations measured after surgery were compared to the preoperatively planned ones as a quality control. We found an average difference of 7.8 degrees (SD 6.3 degrees; 95% CI 3.3 degrees-12.3 degrees) in the angles and an average difference of 1.8 (SD 1.7; 95% CI 0.6-3.0) mm and 1.2 (SD 1.4: 95% CI 0.25-2.2), respectively, in the medial and lateral deviation. In conclusion, we could not confirm the same accuracy of implant position as that claimed by the manufacturer.

  2. A stable and reproducible human blood-brain barrier model derived from hematopoietic stem cells.

    Directory of Open Access Journals (Sweden)

    Romeo Cecchelli

    Full Text Available The human blood brain barrier (BBB is a selective barrier formed by human brain endothelial cells (hBECs, which is important to ensure adequate neuronal function and protect the central nervous system (CNS from disease. The development of human in vitro BBB models is thus of utmost importance for drug discovery programs related to CNS diseases. Here, we describe a method to generate a human BBB model using cord blood-derived hematopoietic stem cells. The cells were initially differentiated into ECs followed by the induction of BBB properties by co-culture with pericytes. The brain-like endothelial cells (BLECs express tight junctions and transporters typically observed in brain endothelium and maintain expression of most in vivo BBB properties for at least 20 days. The model is very reproducible since it can be generated from stem cells isolated from different donors and in different laboratories, and could be used to predict CNS distribution of compounds in human. Finally, we provide evidence that Wnt/β-catenin signaling pathway mediates in part the BBB inductive properties of pericytes.

  3. Exogenous IL-4-Expressing Bone Marrow Mesenchymal Stem Cells for the Treatment of Autoimmune Sensorineural Hearing Loss in a Guinea Pig Model

    Directory of Open Access Journals (Sweden)

    Chang-qiang Tan

    2014-01-01

    Full Text Available Bone marrow mesenchymal stem cells (BMSCs expressing recombinant IL-4 have the potential to remediate inflammatory diseases. We thus investigated whether BMSCs expressing exogenous IL-4 could alleviate autoimmune sensorineural hearing loss. BMSCs isolated from guinea pigs were transfected with recombinant lentivirus expressing IL-4. A total of 33 animals were divided into three groups. Group A received scala tympani injection of IL-4-expressing BMSCs, and Group B received control vector-expressing BMSCs, and Group C received phosphate-buffered saline. The distribution of implanted BMSCs in the inner ears was assessed by immunohistochemistry and fluorescence microscopy. Auditory brain-stem response (ABR was monitored to evaluate the auditory changes. Following BMSCs transplantation, the threshold levels of ABR wave III decreased in Groups A and B and significant differences were observed between these two groups P<0.05. Transplanted BMSCs distributed in the scala tympani and scala vestibuli. In some ears with hearing loss, there was a decrease in the number of spiral ganglion cells and varying degrees of endolymphatic hydrops or floccule. Following transplantation, the lentivirus-infected BMSCs migrated to the inner ear and produced IL-4. Our results demonstrate that, upon transplantation, BMSCs and BMSCs expressing recombinant IL-4 have the ability to remediate the inflammatory injury in autoimmune inner ear diseases.

  4. Accuracy and precision of targeting using frameless stereotactic system in deep brain stimulator implantation surgery

    Directory of Open Access Journals (Sweden)

    Mayur Sharma

    2014-01-01

    Full Text Available Objectives: To assess the accuracy of targeting using NexFrame frameless targeting system during deep brain stimulation (DBS surgery. Materials and Methods: Fifty DBS leads were implanted in 33 patients using the NexFrame (Medtronic, Minneapolis, MN targeting system. Postoperative thin cut CT scans were used for lead localization. X, Y, Z coordinates of the tip of the lead were calculated and compared with the intended target coordinates to assess the targeting error. Comparative frame-based data set was obtained from randomly selected 33 patients during the same period that underwent 65 lead placements using Leksell stereotactic frame. Euclidean vector was calculated for directional error. Multivariate analysis of variance was used to compare the accuracy between two systems. Results: The mean error of targeting using frameless system in medio-lateral plane was 1.4 mm (SD ± 1.3, in antero-posterior plane was 0.9 mm (SD ± 1.0 and in supero-inferior plane Z was 1.0 mm (SD ± 0.9. The mean error of targeting using frame-based system in medio-lateral plane was 1.0 mm (SD ± 0.7, in antero-posterior plane was 0.9 mm (SD ± 0.5 and in supero-inferior plane Z was 0.7 mm (SD ± 0.6. The error in targeting was significantly more (P = 0.03 in the medio-lateral plane using the frameless system as compared to the frame-based system. Mean targeting error in the Euclidean directional vector using frameless system was 2.2 (SD ± 1.6 and using frame-based system was 1.7 (SD ± 0.6 (P = 0.07. There was significantly more error in the first 25 leads placed using the frameless system than the second 25 leads (P = 0.0015. Conclusion: The targeting accuracy of the frameless system was lower as compared to frame-based system in the medio-lateral direction. Standard deviations (SDs were higher using frameless system as compared to the frame-based system indicating lower accuracy of this system. Error in targeting should be considered while using frameless

  5. Strategies for Regenerating Striatal Neurons in the Adult Brain by Using Endogenous Neural Stem Cells

    Directory of Open Access Journals (Sweden)

    Kanako Nakaguchi

    2011-01-01

    Full Text Available Currently, there is no effective treatment for the marked neuronal loss caused by neurodegenerative diseases, such as Huntington's disease (HD or ischemic stroke. However, recent studies have shown that new neurons are continuously generated by endogenous neural stem cells in the subventricular zone (SVZ of the adult mammalian brain, including the human brain. Because some of these new neurons migrate to the injured striatum and differentiate into mature neurons, such new neurons may be able to replace degenerated neurons and improve or repair neurological deficits. To establish a neuroregenerative therapy using this endogenous system, endogenous regulatory mechanisms that can be co-opted for efficient regenerative interventions must be understood, along with any potential drawbacks. Here, we review current knowledge on the generation of new neurons in the adult brain and discuss their potential for use in replacing striatal neurons lost to neurodegenerative diseases, including HD, and to ischemic stroke.

  6. The pros and cons of intraoperative CT scan in evaluation of deep brain stimulation lead implantation: A retrospective study

    Science.gov (United States)

    Servello, Domenico; Zekaj, Edvin; Saleh, Christian; Pacchetti, Claudio; Porta, Mauro

    2016-01-01

    Background: Deep brain stimulation (DBS) is an established therapy for movement disorders, such as Parkinson's disease (PD), dystonia, and tremor. The efficacy of DBS depends on the correct lead positioning. The commonly adopted postoperative radiological evaluation is performed with computed tomography (CT) scan and/or magnetic resonance imaging (MRI). Methods: We conducted a retrospective study on 202 patients who underwent DBS from January 2009 to October 2013. DBS indications were PD, progressive supranuclear palsy, tremor, dystonia, Tourette syndrome, obsessive compulsive disorder, depression, and Huntington's disease. Preoperatively, all patients underwent brain MRI and brain CT scan with the stereotactic frame positioned. The lead location was confirmed intraoperatively with CT. The CT images were subsequently transferred to the Stealth Station Medtronic and merged with the preoperative planning. On the first or second day after, implantation we performed a brain MRI to confirm the correct position of the lead. Results: In 14 patients, leads were in suboptimal position after intraoperative CT scan positioning. The cases with alteration in the Z-axis were corrected immediately under fluoroscopic guidance. In all the 14 patients, an immediate repositioning was done. Conclusions: Based on our data, intraoperative CT scan is fast, safe, and a useful tool in the evaluation of the position of the implanted lead. It also reduces the patient's discomfort derived from the transfer of the patient from the operating room to the radiological department. However, intraoperative CT should not be considered as a substitute for postoperative MRI. PMID:27583182

  7. An auditory multiclass brain-computer interface with natural stimuli: usability evaluation with healthy participants and a motor impaired end user

    Directory of Open Access Journals (Sweden)

    Nadine eSimon

    2015-01-01

    Full Text Available Brain-computer interfaces (BCIs can serve as muscle independent communication aids. Persons, who are unable to control their eye muscles (e.g. in the completely locked-in state or have severe visual impairments for other reasons, need BCI systems that do not rely on the visual modality. For this reason, BCIs that employ auditory stimuli were suggested. In this study, a multiclass BCI spelling system was implemented that uses animal voices with directional cues to code rows and columns of a letter matrix. To reveal possible training effects with the system, 11 healthy participants performed spelling tasks on two consecutive days. In a second step, the system was tested by a participant with amyotrophic lateral sclerosis (ALS in two sessions. In the first session, healthy participants spelled with an average accuracy of 76% (3.29 bits/min that increased to 90% (4.23 bits/min on the second day. Spelling accuracy by the participant with ALS was 20% in the first and 47% in the second session. The results indicate a strong training effect for both the healthy participants and the participant with ALS. While healthy participants reached high accuracies in the first session and second session, accuracies for the participant with ALS were not sufficient for satisfactory communication in both sessions. More training sessions might be needed to improve spelling accuracies. The study demonstrated the feasibility of the auditory BCI with healthy users and stresses the importance of training with auditory multiclass BCIs, especially for potential end-users of BCI with disease.

  8. Long-term survival of human neural stem cells in the ischemic rat brain upon transient immunosuppression.

    Directory of Open Access Journals (Sweden)

    Laura Rota Nodari

    Full Text Available Understanding the physiology of human neural stem cells (hNSCs in the context of cell therapy for neurodegenerative disorders is of paramount importance, yet large-scale studies are hampered by the slow-expansion rate of these cells. To overcome this issue, we previously established immortal, non-transformed, telencephalic-diencephalic hNSCs (IhNSCs from the fetal brain. Here, we investigated the fate of these IhNSC's immediate progeny (i.e. neural progenitors; IhNSC-Ps upon unilateral implantation into the corpus callosum or the hippocampal fissure of adult rat brain, 3 days after global ischemic injury. One month after grafting, approximately one fifth of the IhNSC-Ps had survived and migrated through the corpus callosum, into the cortex or throughout the dentate gyrus of the hippocampus. By the fourth month, they had reached the ipsilateral subventricular zone, CA1-3 hippocampal layers and the controlateral hemisphere. Notably, these results could be accomplished using transient immunosuppression, i.e administering cyclosporine for 15 days following the ischemic event. Furthermore, a concomitant reduction of reactive microglia (Iba1+ cells and of glial, GFAP+ cells was also observed in the ipsilateral hemisphere as compared to the controlateral one. IhNSC-Ps were not tumorigenic and, upon in vivo engraftment, underwent differentiation into GFAP+ astrocytes, and β-tubulinIII+ or MAP2+ neurons, which displayed GABAergic and GLUTAmatergic markers. Electron microscopy analysis pointed to the formation of mature synaptic contacts between host and donor-derived neurons, showing the full maturation of the IhNSC-P-derived neurons and their likely functional integration into the host tissue. Thus, IhNSC-Ps possess long-term survival and engraftment capacity upon transplantation into the globally injured ischemic brain, into which they can integrate and mature into neurons, even under mild, transient immunosuppressive conditions. Most notably

  9. Evoked brain potentials and disability in brain-damaged patients.

    Science.gov (United States)

    Rappaport, M; Hall, K; Hopkins, K; Belleza, T; Berrol, S; Reynolds, G

    1977-08-01

    Various measures of evoked brain potential abnormality (EPA) were correlated with disability ratings (DR) for 35 brain-damaged patients. EPA data consisted of judgements of abnormality of ipsilateral, contralateral and bilateral responses to auditory and visual stimuli reflecting activity in the brain stem, subcortex and cortex. DR data were obtained from a scale developed for this study to quantize and categorize patients with a wide range of disabilities from coma to normal functioning. EPA scores based on visual and auditory cortical responses showed significantly positive correlations with degree of disability. Visual response correlation was .49, auditory .38 and combined visual and auditory .51. It was concluded that EPA measures can reflect disability independently of clinical information. They are useful in assessing brain function in general and, specifically, in assessing impairment of sensory function. The evoked potential technique was particularly useful in patients who were not able to participate fully in their own examination. There were indications that the technique may also be valuable in monitoring progress and in predicting clinical outcome in brain-damaged patients.

  10. 语前聋患儿人工耳蜗植入术后听觉言语功能发育的观察%Development of Auditory and Speech Ability in Prelingual Deafness Children after Cochlear Implantation

    Institute of Scientific and Technical Information of China (English)

    张宏征; 钱宇虹; 郭梦和

    2013-01-01

    目的研究语前聋患儿植入人工耳蜗后听觉言语能力的发育情况及相关因素。方法34例接受人工耳蜗植入的极重度语前聋儿童手术时年龄为1岁2个月~5岁10个月,平均3岁2.15个月,按照植入手术时年龄分为幼龄组(A组,<3岁,17例)、大龄组(B组,≥3岁,17例),在植入手术前和开机后3、6、12个月四个时间点采用有意义听觉整合量表(meaningful auditory integration scale ,MAIS)和婴幼儿有意义听觉整合量表(the infant-toddler meaningful auditory integration scale ,IT -MAIS)对患儿进行听觉能力评估。结果全体患儿植入人工耳蜗后量表总分及三组问题的得分均明显高于植入前,并且随着开机时间的延长其得分逐步上升(P<0.05),其中评价患儿对声音感知能力的Q3~6在开机后的3个月内进展最为迅速。B组植入术前与听觉辅具有关的问题Q1~2和开机后3个月Q3~6得分高于A组(P<0.05),其余各项得分两组间差异无统计学意义。总体上男性和女性患儿各项得分无差异(P>0.05),A组女性患者术前Q1~2得分高于男性(P<0.05),其余各时间点男女间得分差异无统计学意义(P>0.05)。结论随着使用人工耳蜗时间的延长,人工耳蜗植入患儿总体听觉能力呈逐步上升的趋势,进步最快的时间为开机后的3个月内,这个阶段较大龄的患儿对声音的察觉能力优于婴幼儿患者,但随着植入时间的延长两组听觉能力的发育无差异;不同性别患儿植入人工耳蜗后的听觉发育无差异。%Objective To evaluate auditory and speech development longitudinally over the first year after co-chlear implantation in prelingual deaf pediatric cochlear implant (CI) recipients .Methods Meaningful auditory inte-gration scale (MAIS) and infant-toddler meaningful auditory integration scale (ITMAIS) were used to evaluate 34

  11. Successful outcomes of cochlear implantation in long-term unilateral deafness: brain plasticity?

    Science.gov (United States)

    Távora-Vieira, Dayse; Boisvert, Isabelle; McMahon, Catherine M; Maric, Vesna; Rajan, Gunesh P

    2013-09-11

    To investigate the implications of duration of deafness in the rehabilitation of unilateral deafness utilizing cochlear implantation. From the ongoing prospective cochlear implantation in unilateral deafness study, we looked at five adults who received a cochlear implant for long-term unilateral deafness. Speech perception in noise and subjective evaluation of the benefits of cochlear implantation were measured at 3, 6, and 12 months after implantation. The results were analyzed and compared with published data from normal hearing individuals and adults using cochlear implants bilaterally. Analysis of speech perception in noise showed significant improvement for three spatial configurations: speech and noise from the front (S0/N0; P=0.003), speech from the front and noise from the normal hearing ear (S0/NHE; P=0.001), speech from the implanted ear, and noise from the normal hearing ear (SCI/NHE; Pdeafness obtained scores in speech perception testing and in subjective evaluation that are similar to those attained by individuals with normal hearing and/or those with bilateral cochlear implants. Therefore, patients with postlingual unilateral deafness should not be excluded as cochlear implant candidates on the basis of a long duration of deafness.

  12. Nanoparticle-mediated transcriptional modification enhances neuronal differentiation of human neural stem cells following transplantation in rat brain.

    Science.gov (United States)

    Li, Xiaowei; Tzeng, Stephany Y; Liu, Xiaoyan; Tammia, Markus; Cheng, Yu-Hao; Rolfe, Andrew; Sun, Dong; Zhang, Ning; Green, Jordan J; Wen, Xuejun; Mao, Hai-Quan

    2016-04-01

    Strategies to enhance survival and direct the differentiation of stem cells in vivo following transplantation in tissue repair site are critical to realizing the potential of stem cell-based therapies. Here we demonstrated an effective approach to promote neuronal differentiation and maturation of human fetal tissue-derived neural stem cells (hNSCs) in a brain lesion site of a rat traumatic brain injury model using biodegradable nanoparticle-mediated transfection method to deliver key transcriptional factor neurogenin-2 to hNSCs when transplanted with a tailored hyaluronic acid (HA) hydrogel, generating larger number of more mature neurons engrafted to the host brain tissue than non-transfected cells. The nanoparticle-mediated transcription activation method together with an HA hydrogel delivery matrix provides a translatable approach for stem cell-based regenerative therapy.

  13. Cochlear Implant

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this text, the authors recall the main principles and data ruling cochlear implants. Then, a first circle of technical equipment for assistance is presented. This circle includes: device setting (DS), Electrically evoked Auditory Brainstem Responses (EABR), Neural Response Telemetry (NRT), Stapedial Reflex (SR) and Electrodogram Acquisition (EA). This first cycle becomes more and more important as children are implanted younger and younger; the amount of data available with this assistance makes necessary the use of models (implicit or explicit) to handle this information. Consequently, this field is more open than ever.

  14. Dental pulp stem cells repair the immediate implantation for peri-implant bone defects%牙髓干细胞修复即刻种植周围骨缺损

    Institute of Scientific and Technical Information of China (English)

    白慧子; 木合塔尔·霍加; 王腾; 庄友梅

    2016-01-01

    Objective:To establish an animal experimental model of the immediate implantation for peri-implant bone defects of the rabbit mandibular anterior teeth,and observe dental pulp stem cells to repair peri-implant bone defects.Meth-ods:The rabbits that the bilateral mandibular anterior teeth were extracted respectively were divided into 2 groups.Establis-hing bone defect of 2 mm ×3 mm area on the buccal side of tooth extraction socket,and the implant was implanted immedi-ately,that the control group was implanted with Bio-oss and the experimental group with Bio-oss and dental pulp stem cells ( DPSCs) .The implant-osseointegration condition could be evaluated by scanning electron microscope,HE staining.Results:Through scanning electron microscope,the formation of visible woven bone and trabecular bone on implant osseointegration interface of the experimental group could be observed,and the gap between implant and alveolar fossa basically disappeared and between the implant and gingival side decreased,the density of cancellous bone around the implant increased as well.HE staining showed that the cytoplasmic portion of alveolar bone around the implant was vacuole,and the osteoblasts and osteo-clasts were distributed on the trabecular bone,the trabecular bone was compact and regularly arranged.Conclusion:The es-tablishment of an animal experimental model of the immediate implantation for peri-implant bone defects of the rabbit man-dibular anterior teeth can provide an important reference for the relevant research about the immediate implantation direction.%目的:建立兔下颌骨前牙区即刻种植种植体周围骨缺损的动物实验模型,并观察牙髓干细胞在种植体周围骨缺损中骨再生能力。方法:将实验兔分为2组,分别拔除兔双侧下颌前牙,并在拔牙窝颊侧建立2 mm ×3 mm大小骨缺损区,即刻植入种植体。对照组植入Bio-oss骨粉,实验组植入Bio-oss骨粉与牙髓干细胞( Dental Pulp Stem

  15. Photodynamic therapy of malignant brain tumors: supplementary postoperative light delivery by implanted optical fibers: field fractionation

    Science.gov (United States)

    Muller, Paul J.; Wilson, Brian C.

    1991-06-01

    Sixty-three patients with malignant brain tumors were treated with intraoperative photodynamic therapy (PDT) using an argon dye pump laser and preoperatively administered hematoporphyrin derivative or dihematoporphyrin ether. In 13 cases, in addition to cavitary photo-illumination, cylindrical diffusion fibers were used to increase the amount of light energy administered to the tumor tissue intraoperatively. This interstitial photo-illumination was tolerated at light energy densities of less than 450 J/cm. In six recent cases, all of whom had large malignant gliomas and could not be illuminated adequately at a single session, cylindrical diffusion fibers were left in situ after intraoperative cavitary photo-illumination of the tumor residuum. The fibers were protected from fracturing by placing all but the exposed diffusing end in a red rubber catheter of the appropriate diameter. The fibers were externalized through a separate stab wound as would be the case for a ventricular drain. Photo-illumination was continued one or two days post-operatively. The optimal fiber couple to the argon dye pump laser was achieved by assessing the fiber side scatter with a photometer. These six patients received 585-2730 Joules during the post-operative photo-illumination. The patients tolerated the fractionated photo-illumination well. A transient scalp inflammation occurred as the consequence light transmission to skin from the implanted fibers in one case. The median survival for the whole series was 8.5 months (40 weeks) with a 1- and 2-year actuarial survival rate of 33, respectively.

  16. Brain necrosis after permanent low-activity iodine-125 implants: case report and review of toxicity from focal radiation.

    Science.gov (United States)

    Bampoe, J; Nag, S; Leung, P; Laperriere, N; Bernstein, M

    2000-01-01

    Focal irradiation has emerged as a useful modality in the management of malignant brain tumors. Its main limitation is radiation necrosis. We report on the radiation dose distribution in the cerebellum of a patient who developed imaging and autopsy diagnosis of radiation necrosis after permanent iodine-125 implants for a solitary osseous plasmacytoma of her left occipital condyle. A 55-year-old woman initially presented with neck and occipital pain and a lytic lesion of her left occipital condyle. A cytological diagnosis of solitary osseous plasmacytoma was made by transpharyngeal needle biopsy. After an initial course of external beam radiation, the patient required further treatment with systemic chemotherapy 21 months later for clinical and radiographic progression of her disease. She ultimately required subtotal surgical resection of an anaplastic plasmacytoma with intracranial extension. Permanent low-activity iodine-125 seeds were implanted in the tumor cavity. Satisfactory local control was achieved. However, clinical and imaging signs of radiation damage appeared 28 months after iodine-125 seed implantation. Progressive systemic myeloma led to her death 11 years after presentation and 9 years after seed implantation. Radiation dose distribution is described, with a discussion of toxicity from focal radiation dose escalation.

  17. Successful implantation of intravenously administered stem cells correlates with severity of inflammation in murine myocarditis.

    NARCIS (Netherlands)

    Malek, S.; Kaplan, E.; Wang, J.F.; Ke, Q.; Rana, J.S.; Chen, Y.; Rahim, B.G.; Li, M.; Huang, Q.; Xiao, Y.F.; Verheugt, F.W.A.; Morgan, J.P.; Min, J.Y.

    2006-01-01

    The present study was designed to determine whether cardiac inflammation is important for the successful homing of stem cells to the heart after intravenous injection in a murine myocarditis model. Male Bagg albino/c mice were infected with encephalomyocarditis virus (EMCV) to produce myocarditis. S

  18. Resultados auditivos com o implante coclear multicanal em pacientes submetidos a cirurgia no Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo Auditory results with multicanal cochlear implant in patients submitted to cochlear implant surgery at University of São Paulo Medical School - Hospital das Clínicas

    Directory of Open Access Journals (Sweden)

    Ricardo Ferreira Bento

    2004-10-01

    an important alert for dangerous situations in the daily life. They are also unable to hear their own voices and for this people with profound deaf do not modulate their voices. The hearing aids are the first choice to treat deafness, but there are patients with severe damage of the auditory systems who cannot receive a useful hearing from normal hearing aids. The cochlear implant is the alternative for patients that cannot have good discriminatory ability wearing a powerful hearing aid and wish or need a better hearing. AIM: To study the hearing results of the adult patients who are using a multichannel cochlear implant system at the Department of Otolaryngology - University of Sao Paulo. STUDY DESIGN: Series study. MATERIAL AND METHOD: We selected 61 patients with a severe bilateral hearing loss that have been using the cochlear implant for at least six months. The hearing evaluation performed after using the device for six months included word and sentence recognition tests. RESULTS: The PTA of four patients reached 38.7 dB. Speech perception tests showed 713% recognition of open set sentences, 86.5% of vowels and 52.60% of monosyllabic. Most of our patients are able to speak on the telephone. CONCLUSION: Most of patients showed excellent results in open-set sentence and word tests.

  19. Auditory and Visual Sensations

    CERN Document Server

    Ando, Yoichi

    2010-01-01

    Professor Yoichi Ando, acoustic architectural designer of the Kirishima International Concert Hall in Japan, presents a comprehensive rational-scientific approach to designing performance spaces. His theory is based on systematic psychoacoustical observations of spatial hearing and listener preferences, whose neuronal correlates are observed in the neurophysiology of the human brain. A correlation-based model of neuronal signal processing in the central auditory system is proposed in which temporal sensations (pitch, timbre, loudness, duration) are represented by an internal autocorrelation representation, and spatial sensations (sound location, size, diffuseness related to envelopment) are represented by an internal interaural crosscorrelation function. Together these two internal central auditory representations account for the basic auditory qualities that are relevant for listening to music and speech in indoor performance spaces. Observed psychological and neurophysiological commonalities between auditor...

  20. Brain stem and cerebellum volumetric analysis of Machado Joseph disease patients

    Directory of Open Access Journals (Sweden)

    S T Camargos

    2011-01-01

    Full Text Available Machado-Joseph disease, or spinocerebellar ataxia type 3(MJD/SCA3, is the most frequent late onset spinocerebellar ataxia and results from a CAG repeat expansion in the ataxin-3 gene. Previous studies have found correlation between atrophy of cerebellum and brainstem with age and CAG repeats, although no such correlation has been found with disease duration and clinical manifestations. In this study we test the hypothesis that atrophy of cerebellum and brainstem in MJD/SCA3 is related to clinical severity, disease duration and CAG repeat length as well as to other variables such as age and ICARS (International Cooperative Ataxia Rating Scale. Whole brain high resolution MRI and volumetric measurement with cranial volume normalization were obtained from 15 MJD/SCA3 patients and 15 normal, age and sex-matchedcontrols. We applied ICARS and compared the score with volumes and CAG number, disease duration and age. We found significant correlation of both brain stem and cerebellar atrophy with CAG repeat length, age, disease duration and degree of disability. The Spearman rank correlation was stronger with volumetric reduction of the cerebellum than with brain stem. Our data allow us to conclude that volumetric analysis might reveal progressive degeneration after disease onset, which in turn is linked to both age and number of CAG repeat expansions in SCA 3.

  1. Brain vascular pericytes following ischemia have multipotential stem cell activity to differentiate into neural and vascular lineage cells.

    Science.gov (United States)

    Nakagomi, Takayuki; Kubo, Shuji; Nakano-Doi, Akiko; Sakuma, Rika; Lu, Shan; Narita, Aya; Kawahara, Maiko; Taguchi, Akihiko; Matsuyama, Tomohiro

    2015-06-01

    Brain vascular pericytes (PCs) are a key component of the blood-brain barrier (BBB)/neurovascular unit, along with neural and endothelial cells. Besides their crucial role in maintaining the BBB, increasing evidence shows that PCs have multipotential stem cell activity. However, their multipotency has not been considered in the pathological brain, such as after an ischemic stroke. Here, we examined whether brain vascular PCs following ischemia (iPCs) have multipotential stem cell activity and differentiate into neural and vascular lineage cells to reconstruct the BBB/neurovascular unit. Using PCs extracted from ischemic regions (iPCs) from mouse brains and human brain PCs cultured under oxygen/glucose deprivation, we show that PCs developed stemness presumably through reprogramming. The iPCs revealed a complex phenotype of angioblasts, in addition to their original mesenchymal properties, and multidifferentiated into cells from both a neural and vascular lineage. These data indicate that under ischemic/hypoxic conditions, PCs can acquire multipotential stem cell activity and can differentiate into major components of the BBB/neurovascular unit. Thus, these findings support the novel concept that iPCs can contribute to both neurogenesis and vasculogenesis at the site of brain injuries.

  2. Stemming the impact of health professional brain drain from Africa: a systemic review of policy options

    Directory of Open Access Journals (Sweden)

    Edward Zimbudzi

    2013-06-01

    Full Text Available Africa has been losing professionally trained health workers who are the core of the health system of this continent for many years. Faced with an increased burden of disease and coupled by a massive exodus of the health workforce, the health systems of many African nations are risking complete paralysis. Several studies have suggested policy options to reduce brain drain from Africa. The purpose of this paper is to review possible policies, which can stem the impact of health professional brain drain from Africa. A systemic literature review was conducted. Cinahl, Science Direct and PubMed databases were searched with the following terms: health professional brain drain from Africa and policies for reducing impact of brain drain from Africa. References were also browsed for relevant articles. A total of 425 articles were available for the study but only 23 articles met the inclusion criteria. The review identified nine policy options, which were being implemented in Africa, but the most common was task shifting which had success in several African countries. This review has demonstrated that there is considerable consensus on task shifting as the most appropriate and sustainable policy option for reducing the impact of health professional brain drain from Africa.

  3. Activation of endogenous neural stem cells in experimental intracerebral hemorrhagic rat brains

    Institute of Scientific and Technical Information of China (English)

    唐涛; 黎杏群; 武衡; 罗杰坤; 张花先; 罗团连

    2004-01-01

    Background Many researchers suggest that adult mammalian central nervous system (CNS) is incapable of completing self-repair or regeneration. And there are accumulating lines of evidence which suggest that endogenous neural stem cells (NSCs) are activated in many pathological conditions, including stroke in the past decades, which might partly account for rehabilitation afterwards. In this study, we investigated whether there was endogenous neural stem cell activation in intracerebral hemorrhagic (ICH) rat brains.Methods After ICH induction by stereotactical injection of collagenase type Ⅶ into globus pallidus, 5-Bromo-2 Deoxyuridine (BrdU) was administered intraperitoneally to label newborn cells. Immunohistochemical method was used to detect Nestin, a marker for neural stem cells, and BrdU.Results Nestin-positive or BrdU-Labeled cells were predominantly located at 2 sites: basal ganglion around hemotoma, ependyma and nearby subventricular zone (SVZ). No positive cells for the 2 markers were found in the 2 sites of normal control group and sham group, as well as in non-leisoned parenchyma, both hippocampi and olfactory bulbs in the 4 groups. Nestin+ cells presented 4 types of morphology, and BrdU+ nucleus were polymorphologic. Postive cell counting around hemotoma showed that at day 2, Nestin+ cells were seen around hemotoma in model group , the number of which increased at day 4, day 7(P<0.01), peaked at day 14(P<0.05), and reduced significantly by day 28(P<0.01).Conclusion Endogenous neural stem cells were activated in experimental intracerebral hemorrhagic rat brains.

  4. Comparitive Study Between Cnventional and Hyperfractionaltion Radiation Therapy for The Treatment of Brain Stem Tumors

    Directory of Open Access Journals (Sweden)

    Laila Fares * (MD, Mamdouh Salama** (MD Manal Moawad

    2001-06-01

    Full Text Available Brain stem tumors are special challenge because primarily of their location and the neurologic effect caused by these groups of tumors (Paul 1997. Radiation therapy improves survival for brain stem tumors and stabilizes or reverses neurologic dysfunction in 75-90% of patients. The main domain of applicability of hyperfractionation would be in tumor sites where the dose limiting tissue is late reacting and whose effective control requires the delivery of doses beyond tolerance (Awwad, 1990, hence the rationale for the use of hyperfractionation in brain stem lesions. The purpose of this work is to find out the best radiation protocol in this group of patients comparing conventional fractionation and hyperafractionation. This study included 46 patients which brainstem tumors treated in Radiation Oncology and Neurosurgery Departments Ain Shams University between February 1998 and May 2000. These patients had been randomly distributed in 2 groups A and B. The first group treated by conventional radiotherapy protocol and the second group treated by hyperfractionation radiation protocol. By the end of the study, the median over all survival and median time for disease progression were calculated for each group. Age, neurologic status at presentation and anatomical location were significant prognostic factors. By the end of this study clicinal evalualion had no significant difference between both groups but the median over all survival for the two groups was 10.5 months, the median survival for group A was 9.4 months and that for group B was 11.5 months which was statistically significant P < 0.02. On the other hand the percentage of patient with one year survival for group A & B (22%, 32% respectively. The rate of acute (early reaction of radiation is slightly higher in hyperfracticmaticm than conventional fractionation but the late reactions occur with same frequency with both regimens.

  5. Regional brain stem atrophy in idiopathic Parkinson's disease detected by anatomical MRI.

    Science.gov (United States)

    Jubault, Thomas; Brambati, Simona M; Degroot, Clotilde; Kullmann, Benoît; Strafella, Antonio P; Lafontaine, Anne-Louise; Chouinard, Sylvain; Monchi, Oury

    2009-12-10

    Idiopathic Parkinson's disease (PD) is a neurodegenerative disorder characterized by the dysfunction of dopaminergic dependent cortico-basal ganglia loops and diagnosed on the basis of motor symptoms (tremors and/or rigidity and bradykinesia). Post-mortem studies tend to show that the destruction of dopaminergic neurons in the substantia nigra constitutes an intermediate step in a broader neurodegenerative process rather than a unique feature of Parkinson's disease, as a consistent pattern of progression would exist, originating from the medulla oblongata/pontine tegmentum. To date, neuroimaging techniques have been unable to characterize the pre-symptomatic stages of PD. However, if such a regular neurodegenerative pattern were to exist, consistent damages would be found in the brain stem, even at early stages of the disease. We recruited 23 PD patients at Hoenn and Yahr stages I to II of the disease and 18 healthy controls (HC) matched for age. T1-weighted anatomical scans were acquired (MPRAGE, 1 mm3 resolution) and analyzed using an optimized VBM protocol to detect white and grey matter volume reduction without spatial a priori. When the HC group was compared to the PD group, a single cluster exhibited statistical difference (p<0.05 corrected for false detection rate, 4287 mm3) in the brain stem, between the pons and the medulla oblongata. The present study provides in-vivo evidence that brain stem damage may be the first identifiable stage of PD neuropathology, and that the identification of this consistent damage along with other factors could help with earlier diagnosis in the future. This damage could also explain some non-motor symptoms in PD that often precede diagnosis, such as autonomic dysfunction and sleep disorders.

  6. Regional brain stem atrophy in idiopathic Parkinson's disease detected by anatomical MRI.

    Directory of Open Access Journals (Sweden)

    Thomas Jubault

    Full Text Available Idiopathic Parkinson's disease (PD is a neurodegenerative disorder characterized by the dysfunction of dopaminergic dependent cortico-basal ganglia loops and diagnosed on the basis of motor symptoms (tremors and/or rigidity and bradykinesia. Post-mortem studies tend to show that the destruction of dopaminergic neurons in the substantia nigra constitutes an intermediate step in a broader neurodegenerative process rather than a unique feature of Parkinson's disease, as a consistent pattern of progression would exist, originating from the medulla oblongata/pontine tegmentum. To date, neuroimaging techniques have been unable to characterize the pre-symptomatic stages of PD. However, if such a regular neurodegenerative pattern were to exist, consistent damages would be found in the brain stem, even at early stages of the disease. We recruited 23 PD patients at Hoenn and Yahr stages I to II of the disease and 18 healthy controls (HC matched for age. T1-weighted anatomical scans were acquired (MPRAGE, 1 mm3 resolution and analyzed using an optimized VBM protocol to detect white and grey matter volume reduction without spatial a priori. When the HC group was compared to the PD group, a single cluster exhibited statistical difference (p<0.05 corrected for false detection rate, 4287 mm3 in the brain stem, between the pons and the medulla oblongata. The present study provides in-vivo evidence that brain stem damage may be the first identifiable stage of PD neuropathology, and that the identification of this consistent damage along with other factors could help with earlier diagnosis in the future. This damage could also explain some non-motor symptoms in PD that often precede diagnosis, such as autonomic dysfunction and sleep disorders.

  7. 660 nm red light-enhanced bone marrow mesenchymal stem cell transplantation for hypoxic-ischemic brain damage treatment

    Institute of Scientific and Technical Information of China (English)

    Xianchao Li; Wensheng Hou; Xiaoying Wu; Wei Jiang; Haiyan Chen; Nong Xiao; Ping Zhou

    2014-01-01

    Bone marrow mesenchymal stem cell transplantation is an effective treatment for neonatal hy-poxic-ischemic brain damage. However, the in vivo transplantation effects are poor and their survival, colonization and differentiation efifciencies are relatively low. Red or near-infrared light from 600-1,000 nm promotes cellular migration and prevents apoptosis. Thus, we hypothesized that the combination of red light with bone marrow mesenchymal stem cell transplantation would be effective for the treatment of hypoxic-ischemic brain damage. In this study, the migra-tion and colonization of cultured bone marrow mesenchymal stem cells on primary neurons after oxygen-glucose deprivation were detected using Transwell assay. The results showed that, after a 40-hour irradiation under red light-emitting diodes at 660 nm and 60 mW/cm2, an increasing number of green lfuorescence-labeled bone marrow mesenchymal stem cells migrated towards hypoxic-ischemic damaged primary neurons. Meanwhile, neonatal rats with hypoxic-ischemic brain damage were given an intraperitoneal injection of 1 × 106 bone marrow mesenchymal stem cells, followed by irradiation under red light-emitting diodes at 660 nm and 60 mW/cm2 for 7 successive days. Shuttle box test results showed that, after phototherapy and bone marrow mesenchymal stem cell transplantation, the active avoidance response rate of hypoxic-ischemic brain damage rats was significantly increased, which was higher than that after bone marrow mesenchymal stem cell transplantation alone. Experimental ifndings indicate that 660 nm red light emitting diode irradiation promotes the migration of bone marrow mesenchymal stem cells, thereby enhancing the contribution of cell transplantation in the treatment of hypox-ic-ischemic brain damage.

  8. 660 nm red light-enhanced bone marrow mesenchymal stem cell transplantation for hypoxic-ischemic brain damage treatment.

    Science.gov (United States)

    Li, Xianchao; Hou, Wensheng; Wu, Xiaoying; Jiang, Wei; Chen, Haiyan; Xiao, Nong; Zhou, Ping

    2014-02-01

    Bone marrow mesenchymal stem cell transplantation is an effective treatment for neonatal hypoxic-ischemic brain damage. However, the in vivo transplantation effects are poor and their survival, colonization and differentiation efficiencies are relatively low. Red or near-infrared light from 600-1,000 nm promotes cellular migration and prevents apoptosis. Thus, we hypothesized that the combination of red light with bone marrow mesenchymal stem cell transplantation would be effective for the treatment of hypoxic-ischemic brain damage. In this study, the migration and colonization of cultured bone marrow mesenchymal stem cells on primary neurons after oxygen-glucose deprivation were detected using Transwell assay. The results showed that, after a 40-hour irradiation under red light-emitting diodes at 660 nm and 60 mW/cm(2), an increasing number of green fluorescence-labeled bone marrow mesenchymal stem cells migrated towards hypoxic-ischemic damaged primary neurons. Meanwhile, neonatal rats with hypoxic-ischemic brain damage were given an intraperitoneal injection of 1 × 10(6) bone marrow mesenchymal stem cells, followed by irradiation under red light-emitting diodes at 660 nm and 60 mW/cm(2) for 7 successive days. Shuttle box test results showed that, after phototherapy and bone marrow mesenchymal stem cell transplantation, the active avoidance response rate of hypoxic-ischemic brain damage rats was significantly increased, which was higher than that after bone marrow mesenchymal stem cell transplantation alone. Experimental findings indicate that 660 nm red light emitting diode irradiation promotes the migration of bone marrow mesenchymal stem cells, thereby enhancing the contribution of cell transplantation in the treatment of hypoxic-ischemic brain damage.

  9. Science Letters: Brain natriuretic peptide: A potential indicator of cardiomyogenesis after autologous mesenchymal stem cell transplantation?

    Institute of Scientific and Technical Information of China (English)

    LI Nan; WANG Jian-an

    2006-01-01

    We observed in a pilot study that there was a transient elevation of brain natriuretic peptide (BNP) level shortly after the transplantation in the patient with ischemic heart failure, which is unexplainable by the simultaneous increase of the cardiac output and six-minute walk distance. Similar findings were observed in the phase I trial. We postulated on the basis of the finding of Fukuda in vitro that this transient elevation of BNP level against the improvement of cardiac function and exercise capacity might indicate cardiomyogenesis in patients after mesenchymal stem cell transplantation. Further study is warranted to verify the hypothesis.

  10. Adaptation of the communicative brain to post-lingual deafness. Evidence from functional imaging.

    Science.gov (United States)

    Lazard, Diane S; Innes-Brown, Hamish; Barone, Pascal

    2014-01-01

    Not having access to one sense profoundly modifies our interactions with the environment, in turn producing changes in brain organization. Deafness and its rehabilitation by cochlear implantation offer a unique model of brain adaptation during sensory deprivation and recovery. Functional imaging allows the study of brain plasticity as a function of the times of deafness and implantation. Even long after the end of the sensitive period for auditory brain physiological maturation, some plasticity may be observed. In this way the mature brain that becomes deaf after language acquisition can adapt to its modified sensory inputs. Oral communication difficulties induced by post-lingual deafness shape cortical reorganization of brain networks already specialized for processing oral language. Left hemisphere language specialization tends to be more preserved than functions of the right hemisphere. We hypothesize that the right hemisphere offers cognitive resources re-purposed to palliate difficulties in left hemisphere speech processing due to sensory and auditory memory degradation. If cochlear implantation is considered, this reorganization during deafness may influence speech understanding outcomes positively or negatively. Understanding brain plasticity during post-lingual deafness should thus inform the development of cognitive rehabilitation, which promotes positive reorganization of the brain networks that process oral language before surgery. This article is part of a Special Issue entitled Human Auditory Neuroimaging.

  11. Reelin signaling in the migration of ventral brain stem and spinal cord neurons

    Directory of Open Access Journals (Sweden)

    Sandra eBlaess

    2016-03-01

    Full Text Available The extracellular matrix protein Reelin is an important orchestrator of neuronal migration during the development of the central nervous system. While its role and mechanism of action have been extensively studied and reviewed in the formation of dorsal laminar brain structures like the cerebral cortex, hippocampus, and cerebellum, its functions during the neuronal migration events that result in the nuclear organization of the ventral central nervous system are less well understood. In an attempt to delineate an underlying pattern of Reelin action in the formation of neuronal cell clusters, this review highlights the role of Reelin signaling in the migration of neuronal populations that originate in the ventral brain stem and the spinal cord.

  12. Stem cell-based delivery of brain-derived neurotrophic factor gene in the rat retina.

    Science.gov (United States)

    Park, Hae-Young Lopilly; Kim, Jie Hyun; Sun Kim, Hwa; Park, Chan Kee

    2012-08-21

    As an alternative to a viral vector, the application of stem cells to transfer specific genes is under investigation in various organs. Using this strategy may provide more effective method to supply neurotrophic factor to the neurodegenerative diseases caused by neurotrophic factor deprivation. This study investigated the possibility and efficacy of stem cell-based delivery of the brain-derived neurotrophic factor (BDNF) gene to rat retina. Rat BDNF cDNA was transduced into rat bone marrow mesenchymal stem cells (rMSCs) using a retroviral vector. Its incorporation into the experimental rat retina and the expression of BDNF after intravitreal injection or subretinal injection were detected by real-time PCR, western blot analysis, and immunohistochemical staining. For the incorporated rMSCs, retinal-specific marker staining was performed to investigate the changes in morphology and the characteristics of the stem cells. Transduction of the rMSCs by retrovirus was effective, and the transduced rMSCs expressed high levels of the BDNF gene and protein. The subretinal injection of rMSCs produced rMSC migration and incorporation into the rat retina (about 15.7% incorporation rate), and retinal BDNF mRNA and protein expression was increased at 4 weeks after transplantation. When subretinal injection of rMSCs was applied to axotomized rat retina, it significantly increased the expression of BDNF until 4 weeks after transplantation. Some of the transplanted rMSCs exhibited morphological changes, but the retinal-specific marker stain was not sufficient to indicate whether neuronal differentiation had occurred. Using mesenchymal stem cells to deliver the BDNF gene to the retina may provide new treatment for glaucoma.

  13. Research progress in brain tumor stem cells%脑肿瘤干细胞的研究现状

    Institute of Scientific and Technical Information of China (English)

    王欣欣; 刘季平

    2012-01-01

    BACKGROUND: Research in recent years has discovered some stem cell-like cells exist in brain tumors, which have theproperties of endless cell proliferation, uncontrolled self-renewal and multi-directional differentiation, and they are called as braintumor stem cells. Brain tumor stem cells play a key role in the progress of tumorigenesis, growth, invasion, metastasis andrecurrence.OBJECTIVE: To conclude and explore the current studies on brain tumor stem cells.METHODS: A computer-based search of Pubmed Database was performed to retrieve relevant articles about brain tumor andbrain tumor stem cells published from January 1977 to July 2011. Books on stem cells and brain tumor stem cells were alsoretrieved. The data were selected primarily, and 32 articles related to brain tumor stem cells were selected.RESULTS AND CONCLUSION: Brain tumor stem cells exist in malignant brain tumor, and they are the origin of the occurrence,development, metastasis and recurrence of malignant brain tumor. Brain tumor stem cells express CD133, Nestin protein andABC transporter in malignant brain tumors. Recently, a simple method has been obtained to isolate brain tumor stem cells. Theproportion of CD133 positive tumor stem cells is positively correlated with the severity of malignant brain tumors, which can beused as a diagnostic indicator of prognosis.%背景:在脑肿瘤中存在一种具有自我更新、无限增殖与多向分化能力的细胞,即脑肿瘤干细胞.脑肿瘤干细胞被认为是脑肿瘤发生、发展、转移与复发的根源.目的:总结和探讨脑肿瘤干细胞的研究现状.方法:以"脑肿瘤、脑肿瘤干细胞"为检索词,应该计算机检索Pubmed 数据库1977-01/2011-07的相关文章,并查阅与干细胞及脑肿瘤干细胞实验有关的书籍,对资料进行初审,选取符合要求的有关文章共32 篇.结果与结论:在恶性脑肿瘤中存在脑肿瘤干细胞.脑肿瘤干细胞是恶性脑肿瘤发生、发展、转移及复发的

  14. Activin and TGF-β effects on brain development and neural stem cells.

    Science.gov (United States)

    Rodríguez-Martínez, Griselda; Velasco, Iván

    2012-11-01

    Transforming Growth Factor-β (TGF-β) family members are ubiquitously expressed, participating in the regulation of many processes in different cell types both in embryonic and adult stages. Several members of this family, including Activins, TGF-β1-3 and Nodal, have been implicated in the development and maintenance of various organs, in which stem cells play important roles. Although TGF-β was initially considered an injury-related cytokine, it became clear that not only TGF-β, but other members of this family, play critical roles in morphogenesis and cell lineage specification. During brain development, Activin and TGF-βs as well as their cognate receptors, are expressed in different patterns. The roles of Activin and TGF-β during CNS development are sometimes contradictory, because these proteins present different actions depending on the cell type and the context. The aim of this review is to summarize current information on the actions of TGF-β members during developing brain, and also on Neural Stem/Progenitor Cells (NSPC). We focus on the TGF-β subgroup, specifically on the effects of TGF-β1 and Activin A. In the first section we describe the main characteristics of the ligands, its receptors as well as the proteins and mechanisms involved in signaling. Next, we discuss the main advances concerning TGF-β1 and Activin actions during brain development and their roles in NSPC fate decision and neuroprotection both in vitro and in vivo. The emerging picture from these studies suggests that these growth factors can be used to manipulate neurogenesis and might help to achieve restoration after brain deterioration.

  15. Impact of Repetitive Transcranial Magnetic Stimulation (rTMS on Brain Functional Marker of Auditory Hallucinations in Schizophrenia Patients

    Directory of Open Access Journals (Sweden)

    Sonia Dollfus

    2013-04-01

    Full Text Available Several cross-sectional functional Magnetic Resonance Imaging (fMRI studies reported a negative correlation between auditory verbal hallucination (AVH severity and amplitude of the activations during language tasks. The present study assessed the time course of this correlation and its possible structural underpinnings by combining structural, functional MRI and repetitive Transcranial Magnetic Stimulation (rTMS. Methods: Nine schizophrenia patients with AVH (evaluated with the Auditory Hallucination Rating scale; AHRS and nine healthy participants underwent two sessions of an fMRI speech listening paradigm. Meanwhile, patients received high frequency (20 Hz rTMS. Results: Before rTMS, activations were negatively correlated with AHRS in a left posterior superior temporal sulcus (pSTS cluster, considered henceforward as a functional region of interest (fROI. After rTMS, activations in this fROI no longer correlated with AHRS. This decoupling was explained by a significant decrease of AHRS scores after rTMS that contrasted with a relative stability of cerebral activations. A voxel-based-morphometry analysis evidenced a cluster of the left pSTS where grey matter volume negatively correlated with AHRS before rTMS and positively correlated with activations in the fROI at both sessions. Conclusion: rTMS decreases the severity of AVH leading to modify the functional correlate of AVH underlain by grey matter abnormalities.

  16. Impact of Repetitive Transcranial Magnetic Stimulation (rTMS) on Brain Functional Marker of Auditory Hallucinations in Schizophrenia Patients

    Science.gov (United States)

    Maïza, Olivier; Hervé, Pierre-Yve; Etard, Olivier; Razafimandimby, Annick; Montagne-Larmurier, Aurélie; Dollfus, Sonia

    2013-01-01

    Several cross-sectional functional Magnetic Resonance Imaging (fMRI) studies reported a negative correlation between auditory verbal hallucination (AVH) severity and amplitude of the activations during language tasks. The present study assessed the time course of this correlation and its possible structural underpinnings by combining structural, functional MRI and repetitive Transcranial Magnetic Stimulation (rTMS). Methods: Nine schizophrenia patients with AVH (evaluated with the Auditory Hallucination Rating scale; AHRS) and nine healthy participants underwent two sessions of an fMRI speech listening paradigm. Meanwhile, patients received high frequency (20 Hz) rTMS. Results: Before rTMS, activations were negatively correlated with AHRS in a left posterior superior temporal sulcus (pSTS) cluster, considered henceforward as a functional region of interest (fROI). After rTMS, activations in this fROI no longer correlated with AHRS. This decoupling was explained by a significant decrease of AHRS scores after rTMS that contrasted with a relative stability of cerebral activations. A voxel-based-morphometry analysis evidenced a cluster of the left pSTS where grey matter volume negatively correlated with AHRS before rTMS and positively correlated with activations in the fROI at both sessions. Conclusion: rTMS decreases the severity of AVH leading to modify the functional correlate of AVH underlain by grey matter abnormalities. PMID:24961421

  17. Cochlear implant outcomes and genetic mutations in children with ear and brain anomalies

    OpenAIRE

    Busi, Micol

    2013-01-01

    Introduction. Cochlear implantation (CI) was a significant surgical innovation in the 20th century and represented the first artificial sensory organ that was applied in clinical medicine. Currently, CI is still one of the most effective medical procedures. Nonetheless, cochlear implantation in adults and children represents a controversial issue from an economic, clinical and ethical point of view, especially in specific clinical conditions that could compromise the CI outcome and drasticall...

  18. Estradiol-dependent catecholaminergic innervation of auditory areas in a seasonally breeding songbird.

    Science.gov (United States)

    Matragrano, Lisa L; Sanford, Sara E; Salvante, Katrina G; Sockman, Keith W; Maney, Donna L

    2011-08-01

    A growing body of evidence suggests that gonadal steroids such as estradiol (E2) alter neural responses not only in brain regions associated with reproductive behavior but also in sensory areas. Because catecholamine systems are involved in sensory processing and selective attention, and because they are sensitive to E2 in many species, they may mediate the neural effects of E2 in sensory areas. Here, we tested the effects of E2 on catecholaminergic innervation, synthesis and activity in the auditory system of white-throated sparrows, a seasonally breeding songbird in which E2 promotes selective auditory responses to song. Non-breeding females with regressed ovaries were held on a winter-like photoperiod and implanted with silastic capsules containing either no hormone or E2. In one hemisphere of the brain, we used immunohistochemistry to quantify fibers immunoreactive for tyrosine hydroxylase or dopamine beta-hydroxylase in the auditory forebrain, thalamus and midbrain. E2 treatment increased catecholaminergic innervation in the same areas of the auditory system in which E2 promotes selectivity for song. In the contralateral hemisphere we quantified dopamine, norepinephrine and their metabolites in tissue punches using HPLC. Norepinephrine increased in the auditory forebrain, but not the midbrain, after E2 treatment. We found that evidence of interhemispheric differences, both in immunoreactivity and catecholamine content that did not depend on E2 treatment. Overall, our results show that increases in plasma E2 typical of the breeding season enhanced catecholaminergic innervation and synthesis in some parts of the auditory system, raising the possibility that catecholamines play a role in E2-dependent auditory plasticity in songbirds.

  19. Brain components

    Science.gov (United States)

    ... can make complex movements without thinking. The brain stem connects the brain with the spinal cord and is composed of ... structures: the midbrain, pons, and medulla oblongata. The brain stem provides us with automatic functions that are necessary ...

  20. Utilizing pharmacotherapy and mesenchymal stem cell therapy to reduce inlfammation following traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Sherwin Mashkouri; Marci G. Crowley; Michael G. Liska; Sydney Corey; Cesar V. Borlongan

    2016-01-01

    The pathologic process of chronic phase traumatic brain injury is associated with spreading inlfamma-tion, cell death, and neural dysfunction. It is thought that sequestration of inlfammatory mediators can facilitate recovery and promote an environment that fosters cellular regeneration. Studies have targeted post-traumatic brain injury inlfammation with the use of pharmacotherapy and cell therapy. These thera-peutic options are aimed at reducing the edematous and neurodegenerative inlfammation that have been associated with compromising the integrity of the blood-brain barrier. Although studies have yielded posi-tive results from anti-inlfammatory pharmacotherapy and cell therapy individually, emerging research has begun to target inlfammation using combination therapy. The joint use of anti-inlfammatory drugs along-side stem cell transplantation may provide better clinical outcomes for traumatic brain injury patients. Despite the promising results in this ifeld of research, it is important to note that most of the studies men-tioned in this review have completed their studies using animal models. Translation of this research into a clinical setting will require additional laboratory experiments and larger preclinical trials.

  1. Neural stem cell-based dual suicide gene delivery for metastatic brain tumors.

    Science.gov (United States)

    Wang, C; Natsume, A; Lee, H J; Motomura, K; Nishimira, Y; Ohno, M; Ito, M; Kinjo, S; Momota, H; Iwami, K; Ohka, F; Wakabayashi, T; Kim, S U

    2012-11-01

    In our previous works, we demonstrated that human neural stem cells (NSCs) transduced with the cytosine deaminase (CD) gene showed remarkable 'bystander killer effect' on glioma and medulloblastoma cells after administration of the prodrug 5-fluorocytosine (5-FC). In addition, herpes simplex virus thymidine kinase (TK) is a widely studied enzyme used for suicide gene strategies, for which the prodrug is ganciclovir (GCV). To apply this strategy to brain metastasis treatment, we established here a human NSC line (F3.CD-TK) expressing the dual suicide genes CD and TK. We examined whether F3.CD-TK cells intensified the antitumor effect on lung cancer brain metastases. In vitro studies showed that F3.CD-TK cells exerted a marked bystander effect on human lung cancer cells after treatment with 5-FC and GCV. In a novel experimental brain metastases model, intravenously administered F3 cells migrated near lung cancer metastatic lesions, which were induced by the injection of lung cancer cells via the intracarotid artery. More importantly, F3.CD-TK cells in the presence of prodrugs 5-FC and GCV decreased tumor size and considerably prolonged animal survival. The results of the present study indicate that the dual suicide gene-engineered, NSC-based treatment strategy might offer a new promising therapeutic modality for brain metastases.

  2. Injection of SDF-1 loaded nanoparticles following traumatic brain injury stimulates neural stem cell recruitment.

    Science.gov (United States)

    Zamproni, Laura N; Mundim, Mayara V; Porcionatto, Marimelia A; des Rieux, Anne

    2017-03-15

    Recruiting neural stem cell (NSC) at the lesion site is essential for central nervous system repair. This process could be triggered by the local delivery of the chemokine SDF-1. We compared two PLGA formulations for local brain SDF-1 delivery: SDF-1 loaded microspheres (MS) and SDF-1 loaded nanoparticles (NP). Both formulations were able to encapsulate more than 80% of SDF-1 but presented different release profiles, with 100% of SDF-1 released after 6days for the MS and with 25% of SDF-1 released after 2 weeks for NP. SDF-1 bioactivity was demonstrated by a chemotactic assay. When injected in mouse brain after traumatic brain injury, only SDF-1 nanoparticles induced NSC migration to the damage area. More neuroblasts (DCX+ cells) could be visualized around the lesions treated with NP SDF-1 compared to the other conditions. Rostral migratory stream destabilization with massive migration of DCX+ cell toward the perilesional area was observed 2 weeks after NP SDF-1 injection. Local injection of SDF-1-loaded nanoparticles induces recruitment of NSC and could be promising for brain injury lesion.

  3. Clinical outcomes of osteonecrosis of the femoral head after autologous bone marrow stem cell implantation: a meta-analysis of seven case-control studies.

    Science.gov (United States)

    Yuan, Heng-Feng; Zhang, Jing; Guo, Chang-An; Yan, Zuo-Qin

    2016-02-01

    The purpose of this study was to evaluate the clinical outcomes of osteonecrosis of the femoral head after autologous bone marrow stem cell implantation. We searched the PubMed, Embase and Web of Science databases and included all case-control trials that reported on the clinical outcomes of osteonecrosis progression, incidence of total hip arthroplasty and improvement in Harris hip scores. Overall, seven case-control trials were included. Compared with the controls, patients treated with the bone marrow stem cells implantation treatment showed improved clinical outcomes with delayed osteonecrosis progression (odds ratio = 0.17, 95% CI: 0.09 - 0.32; p osteonecrosis of the femoral, resulting in beneficial clinical outcomes. However, trials with larger sample sizes are needed to confirm these findings.

  4. [A comparison of time resolution among auditory, tactile and promontory electrical stimulation--superiority of cochlear implants as human communication aids].

    Science.gov (United States)

    Matsushima, J; Kumagai, M; Harada, C; Takahashi, K; Inuyama, Y; Ifukube, T

    1992-09-01

    Our previous reports showed that second formant information, using a speech coding method, could be transmitted through an electrode on the promontory. However, second formant information can also be transmitted by tactile stimulation. Therefore, to find out whether electrical stimulation of the auditory nerve would be superior to tactile stimulation for our speech coding method, the time resolutions of the two modes of stimulation were compared. The results showed that the time resolution of electrical promontory stimulation was three times better than the time resolution of tactile stimulation of the finger. This indicates that electrical stimulation of the auditory nerve is much better for our speech coding method than tactile stimulation of the finger.

  5. Lab-on-a-brain: Implantable micro-optical fluidic devices for neural cell analysis in vivo

    Science.gov (United States)

    Takehara, Hiroaki; Nagaoka, Akira; Noguchi, Jun; Akagi, Takanori; Kasai, Haruo; Ichiki, Takanori

    2014-10-01

    The high-resolution imaging of neural cells in vivo has brought about great progress in neuroscience research. Here, we report a novel experimental platform, where the intact brain of a living mouse can be studied with the aid of a surgically implanted micro-optical fluidic device; acting as an interface between neurons and the outer world. The newly developed device provides the functions required for the long-term and high-resolution observation of the fine structures of neurons by two-photon laser scanning microscopy and the microfluidic delivery of chemicals or drugs directly into the brain. A proof-of-concept experiment of single-synapse stimulation by two-photon uncaging of caged glutamate and observation of dendritic spine shrinkage over subsequent days demonstrated a promising use for the present technology.

  6. Maternal Inflammation Contributes to Brain Overgrowth and Autism-Associated Behaviors through Altered Redox Signaling in Stem and Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Janel E. Le Belle

    2014-11-01

    Full Text Available A period of mild brain overgrowth with an unknown etiology has been identified as one of the most common phenotypes in autism. Here, we test the hypothesis that maternal inflammation during critical periods of embryonic development can cause brain overgrowth and autism-associated behaviors as a result of altered neural stem cell function. Pregnant mice treated with low-dose lipopolysaccharide at embryonic day 9 had offspring with brain overgrowth, with a more pronounced effect in PTEN heterozygotes. Exposure to maternal inflammation also enhanced NADPH oxidase (NOX-PI3K pathway signaling, stimulated the hyperproliferation of neural stem and progenitor cells, increased forebrain microglia, and produced abnormal autism-associated behaviors in affected pups. Our evidence supports the idea that a prenatal neuroinflammatory dysregulation in neural stem cell redox signaling can act in concert with underlying genetic susceptibilities to affect cellular responses to environmentally altered cellular levels of reactive oxygen species.

  7. Maternal inflammation contributes to brain overgrowth and autism-associated behaviors through altered redox signaling in stem and progenitor cells.

    Science.gov (United States)

    Le Belle, Janel E; Sperry, Jantzen; Ngo, Amy; Ghochani, Yasmin; Laks, Dan R; López-Aranda, Manuel; Silva, Alcino J; Kornblum, Harley I

    2014-11-11

    A period of mild brain overgrowth with an unknown etiology has been identified as one of the most common phenotypes in autism. Here, we test the hypothesis that maternal inflammation during critical periods of embryonic development can cause brain overgrowth and autism-associated behaviors as a result of altered neural stem cell function. Pregnant mice treated with low-dose lipopolysaccharide at embryonic day 9 had offspring with brain overgrowth, with a more pronounced effect in PTEN heterozygotes. Exposure to maternal inflammation also enhanced NADPH oxidase (NOX)-PI3K pathway signaling, stimulated the hyperproliferation of neural stem and progenitor cells, increased forebrain microglia, and produced abnormal autism-associated behaviors in affected pups. Our evidence supports the idea that a prenatal neuroinflammatory dysregulation in neural stem cell redox signaling can act in concert with underlying genetic susceptibilities to affect cellular responses to environmentally altered cellular levels of reactive oxygen species.

  8. Revision of hip resurfacing arthroplasty with a bone-conserving short-stem implant: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Schmidutz Florian

    2012-08-01

    Full Text Available Abstract Introduction Suitable treatment of early failure of total hip replacement is critical in younger patients, as bone stock is lost and the functional outcome is impaired. Case presentation We report the case of a 56-year-old Caucasian woman with early failure of hip resurfacing arthroplasty. While revision is usually performed with a conventional hip implant, this case report describes for the first time a revision procedure with a bone-conserving short-stem hip implant. Conclusions Our approach allows further conservation of femoral bone stock and provides a long-term solution to the patient, which maintains the possibility of using a conventional hip implant should a second revision become necessary.

  9. In vivo imaging of endogenous neural stem cells in theadult brain

    Institute of Scientific and Technical Information of China (English)

    Maria Adele Rueger; Michael Schroeter

    2015-01-01

    The discovery of endogenous neural stem cells (eNSCs) inthe adult mammalian brain with their ability to self-renewand differentiate into functional neurons, astrocytes andoligodendrocytes has raised the hope for novel therapiesof neurological diseases. Experimentally, those eNSCscan be mobilized in vivo , enhancing regeneration andaccelerating functional recovery after, e.g., focal cerebralischemia, thus constituting a most promising approachin stem cell research. In order to translate those currentexperimental approaches into a clinical setting in thefuture, non-invasive imaging methods are required tomonitor eNSC activation in a longitudinal and intraindividualmanner. As yet, imaging protocols to assesseNSC mobilization non-invasively in the live brain remainscarce, but considerable progress has been made inthis field in recent years. This review summarizes anddiscusses the current imaging modalities suitable tomonitor eNSCs in individual experimental animals overtime, including optical imaging, magnetic resonancetomography and-spectroscopy, as well as positronemission tomography (PET). Special emphasis is puton the potential of each imaging method for a possibleclinical translation, and on the specificity of the signalobtained. PET-imaging with the radiotracer 3'-deoxy-3'-[18F]fluoro-L-thymidine in particular constitutes amodality with excellent potential for clinical translationbut low specificity; however, concomitant imaging ofneuroinflammation is feasible and increases its specificity.The non-invasive imaging strategies presented here allowfor the exploitation of novel treatment strategies basedupon the regenerative potential of eNSCs, and will helpto facilitate a translation into the clinical setting.

  10. Morphological and histochemical changes in the brain stem in case of experimental hemispheric intracerebral hemorrhage

    Directory of Open Access Journals (Sweden)

    S. I. Tertishniy

    2015-10-01

    Full Text Available Aim. Investigation of the extent of morphological changes and activity of biogenic amines (according to the intensity of luminescence in the neurons of the brain stem in intracerebral hemorrhage (ICH. Methods and results. ICH was designed on 29 white rats of Vistar line by the administration of autologous blood in the cerebral hemisphere. It was revealed that increased luminescence intensity by 18.4±5.5% was registered in monoaminergic neurons in 1–6 hours after experimental ICH. After 12 hours – 1 day development of dislocation syndrome leads to mosaic focal ischemic neuronal injuries with maximum reduction in the level of catecholamines by 29.5±5.0% compared with control cases. Three–6 days after ICH on a background of selective neuronal necrosis in substantial number of neurons in the nuclei of the brainstem the level of catecholamines is significantly reduced. Conclusion. Disclosed observations reflect significant functional pathology of neurons responsible for the regulation of cardiorespiratory function and may underlie disturbances of integrative activity in the brain stem in general.

  11. Implicit learning of predictable sound sequences modulates human brain responses at different levels of the auditory hierarchy

    Directory of Open Access Journals (Sweden)

    Françoise eLecaignard

    2015-09-01

    Full Text Available Deviant stimuli, violating regularities in a sensory environment, elicit the Mismatch Negativity (MMN, largely described in the Event-Related Potential literature. While it is widely accepted that the MMN reflects more than basic change detection, a comprehensive description of mental processes modulating this response is still lacking. Within the framework of predictive coding, deviance processing is part of an inference process where prediction errors (the mismatch between incoming sensations and predictions established through experience are minimized. In this view, the MMN is a measure of prediction error, which yields specific expectations regarding its modulations by various experimental factors. In particular, it predicts that the MMN should decrease as the occurrence of a deviance becomes more predictable. We conducted a passive oddball EEG study and manipulated the predictability of sound sequences by means of different temporal structures. Importantly, our design allows comparing mismatch responses elicited by predictable and unpredictable violations of a simple repetition rule and therefore departs from previous studies that investigate violations of different time-scale regularities. We observed a decrease of the MMN with predictability and interestingly, a similar effect at earlier latencies, within 70 ms after deviance onset. Following these pre-attentive responses, a reduced P3a was measured in the case of predictable deviants. We conclude that early and late deviance responses reflect prediction errors, triggering belief updating within the auditory hierarchy. Beside, in this passive study, such perceptual inference appears to be modulated by higher-level implicit learning of sequence statistical structures. Our findings argue for a hierarchical model of auditory processing where predictive coding enables implicit extraction of environmental regularities.

  12. Application of an interface failure model to predict fatigue crack growth in an implanted metallic femoral stem.

    Science.gov (United States)

    Chen, J; Browne, M; Taylor, M; Gregson, P J

    2004-03-01

    A novel computational modelling technique has been developed for the prediction of crack growth in load bearing orthopaedic alloys subjected to fatigue loading. Elastic-plastic fracture mechanics has been used to define a three-dimensional fracture model, which explicitly models the opening, sliding and tearing process. This model consists of 3D nonlinear spring elements implemented in conjunction with a brittle material failure function, which is defined by the fracture energy for each nonlinear spring element. Thus, the fracture energy criterion is implicit in the brittle material failure function to search for crack initiation and crack development automatically. A degradation function is employed to reduce interfacial fracture properties corresponding to the number of cycles; thus fatigue lifetime can be predicted. Unlike other failure modelling methods, this model predicts the failure load, crack path and residual stiffness directly without assuming any pre-flaw condition. As an example, fatigue of a cobalt based alloy (CoCrMo) femoral stem is simulated. Experimental fatigue data was obtained from four point bending tests. The finite element model simulated a fully embedded implant with a constant point load. Comparison between the model and mechanical test results showed good agreement in fatigue crack growth rate.

  13. Real Time Imaging of Biomarkers in the Parkinson's Brain Using Mini-Implantable Biosensors. II. Pharmaceutical Therapy with Bromocriptine

    Directory of Open Access Journals (Sweden)

    Patricia A. Broderick

    2009-12-01

    Full Text Available We used Neuromolecular Imaging (NMI and trademarked BRODERICK PROBE® mini-implantable biosensors, to selectively and separately detect neurotransmitters in vivo, on line, within seconds in the dorsal striatal brain of the Parkinson’s Disease (PD animal model. We directly compared our results derived from PD to the normal striatal brain of the non-Parkinson’s Disease (non-PD animal. This advanced biotechnology enabled the imaging of dopamine (DA, serotonin (5-HT, homovanillic acid (HVA a metabolite of DA, L-tryptophan (L-TP a precursor to 5-HT and peptides, dynorphin A 1-17 (Dyn A and somatostatin (somatostatin releasing inhibitory factor (SRIF. Each neurotransmitter and neurochemical was imaged at a signature electroactive oxidation/half-wave potential in dorsal striatum of the PD as compared with the non-PD animal. Both endogenous and bromocriptine-treated neurochemical profiles in PD and non-PD were imaged using the same experimental paradigm and detection sensitivities. Results showed that we have found significant neurotransmitter peptide biomarkers in the dorsal striatal brain of endogenous and bromocriptine-treated PD animals. The peptide biomarkers were not imaged in dorsal striatal brain of non-PD animals, either endogenously or bromocriptine-treated. These findings provide new pharmacotherapeutic strategies for PD patients. Thus, our findings are highly applicable to the clinical treatment of PD.

  14. Guidelines for the pathoanatomical examination of the lower brain stem in ingestive and swallowing disorders and its application to a dysphagic spinocerebellar ataxia type 3 patient

    NARCIS (Netherlands)

    Rub, U; Brunt, ER; Del Turco, D; de Vos, RAI; Gierga, K; Paulson, H; Braak, H

    2003-01-01

    Despite the fact that considerable progress has been made in the last 20 years regarding the three-phase process of ingestion and the lower brain stem nuclei involved in it, no comprehensive descriptions of the ingestion-related lower brain stem nuclei are available for neuropathologists confronted

  15. MicroRNA network changes in the brain stem underlie the development of hypertension.

    Science.gov (United States)

    DeCicco, Danielle; Zhu, Haisun; Brureau, Anthony; Schwaber, James S; Vadigepalli, Rajanikanth

    2015-09-01

    Hypertension is a major chronic disease whose molecular mechanisms remain poorly understood. We compared neuroanatomical patterns of microRNAs in the brain stem of the spontaneous hypertensive rat (SHR) to the Wistar Kyoto rat (WKY, control). We quantified 419 well-annotated microRNAs in the nucleus of the solitary tract (NTS) and rostral ventrolateral medulla (RVLM), from SHR and WKY rats, during three main stages of hypertension development. Changes in microRNA expression were stage- and region-dependent, with a majority of SHR vs. WKY differential expression occurring at the hypertension onset stage in NTS versus at the prehypertension stage in RVLM. Our analysis identified 24 microRNAs showing time-dependent differential expression in SHR compared with WKY in at least one brain region. We predicted potential gene regulatory targets corresponding to catecholaminergic processes, neuroinflammation, and neuromodulation using the miRWALK and RNA22 databases, and we tested those bioinformatics predictions using high-throughput quantitative PCR to evaluate correlations of differential expression between the microRNAs and their predicted gene targets. We found a novel regulatory network motif consisting of microRNAs likely downregulating a negative regulator of prohypertensive processes such as angiotensin II signaling and leukotriene-based inflammation. Our results provide new evidence on the dynamics of microRNA expression in the development of hypertension and predictions of microRNA-mediated regulatory networks playing a region-dependent role in potentially altering brain-stem cardiovascular control circuit function leading to the development of hypertension.

  16. Physical weight loading induces expression of tryptophan hydroxylase 2 in the brain stem.

    Directory of Open Access Journals (Sweden)

    Joon W Shim

    Full Text Available Sustaining brain serotonin is essential in mental health. Physical activities can attenuate mental problems by enhancing serotonin signaling. However, such activity is not always possible in disabled individuals or patients with dementia. Knee loading, a form of physical activity, has been found to mimic effects of voluntary exercise. Focusing on serotonergic signaling, we addressed a question: Does local mechanical loading to the skeleton elevate expression of tryptophan hydroxylase 2 (tph2 that is a rate-limiting enzyme for brain serotonin? A 5 min knee loading was applied to mice using 1 N force at 5 Hz for 1,500 cycles. A 5-min treadmill running was used as an exercise (positive control, and a 90-min tail suspension was used as a stress (negative control. Expression of tph2 was determined 30 min - 2 h in three brain regions --frontal cortex (FC, ventromedial hypothalamus (VMH, and brain stem (BS. We demonstrated for the first time that knee loading and treadmill exercise upregulated the mRNA level of tph2 in the BS, while tail suspension downregulated it. The protein level of tph2 in the BS was also upregulated by knee loading and downregulated by tail suspension. Furthermore, the downregulation of tph2 mRNA by tail suspension can be partially suppressed by pre-application of knee loading. The expression of tph2 in the FC and VMH was not significantly altered with knee loading. In this study we provided evidence that peripheral mechanical loading can activate central tph2 expression, suggesting that physical cues may mediate tph2-cathalyzed serotonergic signaling in the brain.

  17. Evaluation of Evoked Potentials to Dyadic Tones after Cochlear Implantation

    Science.gov (United States)

    Sandmann, Pascale; Eichele, Tom; Buechler, Michael; Debener, Stefan; Jancke, Lutz; Dillier, Norbert; Hugdahl, Kenneth; Meyer, Martin

    2009-01-01

    Auditory evoked potentials are tools widely used to assess auditory cortex functions in clinical context. However, in cochlear implant users, electrophysiological measures are challenging due to implant-created artefacts in the EEG. Here, we used independent component analysis to reduce cochlear implant-related artefacts in event-related EEGs of…

  18. Atomic layer deposited TiO{sub 2} for implantable brain-chip interfacing devices

    Energy Technology Data Exchange (ETDEWEB)

    Cianci, E., E-mail: elena.cianci@mdm.imm.cnr.it [Laboratorio MDM, IMM-CNR, 20864 Agrate Brianza (MB) (Italy); Lattanzio, S. [Istituto di Fisiologia, Dipartimento di Anatomia Umana e Fisiologia, Universita di Padova, 35131 Padova (Italy); Dipartimento di Ingegneria dell' Informazione, Universita di Padova, 35131 Padova (Italy); Seguini, G. [Laboratorio MDM, IMM-CNR, 20864 Agrate Brianza (Italy); Vassanelli, S. [Istituto di Fisiologia, Dipartimento di Anatomia Umana e Fisiologia, Universita di Padova, 35131 Padova (Italy); Fanciulli, M. [Laboratorio MDM, IMM-CNR, 20864 Agrate Brianza (Italy); Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano-Bicocca, 20126 Milano (Italy)

    2012-05-01

    In this paper we investigated atomic layer deposition (ALD) TiO{sub 2} thin films deposited on implantable neuro-chips based on electrolyte-oxide-semiconductor (EOS) junctions, implementing both efficient capacitive neuron-silicon coupling and biocompatibility for long-term implantable functionality. The ALD process was performed at 295 Degree-Sign C using titanium tetraisopropoxide and ozone as precursors on needle-shaped silicon substrates. Engineering of the capacitance of the EOS junctions introducing a thin Al{sub 2}O{sub 3} buffer layer between TiO{sub 2} and silicon resulted in a further increase of the specific capacitance. Biocompatibility for long-term implantable neuroprosthetic systems was checked upon in-vitro treatment.

  19. The role of cancer stem cells and miRNAs in defining the complexities of brain metastasis

    OpenAIRE

    2013-01-01

    Researchers and clinicians have been challenged with the development of therapies for the treatment of cancer patients whose tumors metastasized to the brain. Among the most lethal weapons known today, current management of brain metastases involves multiple therapeutic modalities that provide little, if any, for improving the quality of life and overall survival. Recently the role of cancer stem cells (CSCs) in the development of cancer has been studied extensively, and thus its role in the ...

  20. Auditory Neuropathy - A Case of Auditory Neuropathy after Hyperbilirubinemia

    Directory of Open Access Journals (Sweden)

    Maliheh Mazaher Yazdi

    2007-12-01

    Full Text Available Background and Aim: Auditory neuropathy is an hearing disorder in which peripheral hearing is normal, but the eighth nerve and brainstem are abnormal. By clinical definition, patient with this disorder have normal OAE, but exhibit an absent or severely abnormal ABR. Auditory neuropathy was first reported in the late 1970s as different methods could identify discrepancy between absent ABR and present hearing threshold. Speech understanding difficulties are worse than can be predicted from other tests of hearing function. Auditory neuropathy may also affect vestibular function. Case Report: This article presents electrophysiological and behavioral data from a case of auditory neuropathy in a child with normal hearing after bilirubinemia in a 5 years follow-up. Audiological findings demonstrate remarkable changes after multidisciplinary rehabilitation. Conclusion: auditory neuropathy may involve damage to the inner hair cells-specialized sensory cells in the inner ear that transmit information about sound through the nervous system to the brain. Other causes may include faulty connections between the inner hair cells and the nerve leading from the inner ear to the brain or damage to the nerve itself. People with auditory neuropathy have OAEs response but absent ABR and hearing loss threshold that can be permanent, get worse or get better.

  1. Imaging Evaluation of Pediatric Sensorineural Hearing Loss in Potential Candidates for Cochlear Implantation

    OpenAIRE

    Jallu, Aleena Shafi; Jehangir, Majid; Ul Hamid, Waqar; Pampori, Rafiq Ahmad

    2015-01-01

    Computerized tomography (CT) and magnetic resonance (MR) are complementary in the imaging of the labyrinth, the internal auditory canal and the brain in children with sensorineural hearing loss who are being evaluated for cochlear implantation. An accurate anatomical description of the inner ear is essential in the preoperative work up. Computerized tomography visualizes the bony structures, whereas MR can discern soft-tissue components including intra labyrinthine fluid, cerebrospinal fluid ...

  2. Treatment of osteochondral defects in the rabbit's knee joint by implantation of allogeneic mesenchymal stem cells in fibrin clots.

    Science.gov (United States)

    Berninger, Markus T; Wexel, Gabriele; Rummeny, Ernst J; Imhoff, Andreas B; Anton, Martina; Henning, Tobias D; Vogt, Stephan

    2013-05-21

    repair and has already successfully been used in several animal studies (19-21) and even first human trials (22). The following protocol will demonstrate an experimental technique for isolating mesenchymal stem cells from a rabbit's bone marrow, for subsequent proliferation in cell culture and for preparing a standardized in vitro-model for fibrin-cell-clots. Finally, a technique for the implantation of pre-established fibrin-cell-clots into artificial osteochondral defects of the rabbit's knee joint will be described.

  3. Human umbilical cord blood stem cells and brain-derived neurotrophic factor for optic nerve injury:a biomechanical evaluation

    Institute of Scientific and Technical Information of China (English)

    Zhong-jun Zhang; Ya-jun Li; Xiao-guang Liu; Feng-xiao Huang; Tie-jun Liu; Dong-mei Jiang; Xue-man Lv; Min Luo

    2015-01-01

    Treatment for optic nerve injury by brain-derived neurotrophic factor or the transplantation of human umbilical cord blood stem cells has gained progress, but analysis by biomechanical indicators is rare. Rabbit models of optic nerve injury were established by a clamp. At 7 days after injury, the vitreous body received a one-time injection of 50 μg brain-derived neurotrophic factor or 1 × 106 human umbilical cord blood stem cells. After 30 days, the maximum load, max-imum stress, maximum strain, elastic limit load, elastic limit stress, and elastic limit strain had clearly improved in rabbit models of optical nerve injury after treatment with brain-derived neu-rotrophic factor or human umbilical cord blood stem cells. The damage to the ultrastructure of the optic nerve had also been reduced. These ifndings suggest that human umbilical cord blood stem cells and brain-derived neurotrophic factor effectively repair the injured optical nerve, im-prove biomechanical properties, and contribute to the recovery after injury.

  4. Collateralization of the pathways descending from the cerebral cortex to brain stem and spinal cord in cat and monkey

    NARCIS (Netherlands)

    K. Keizer (Koos)

    1989-01-01

    textabstractThe present study deals with the collateralization of the descending pathways from the cerebral cortex to the brain stem and the spinal cord in cat and monkey. The distributions of the branching cortical neurons were studied using retrograde fluorescent tracers. In addition, a new retrog

  5. Growth of G422 glioma implanted in the mouse brain was affected by the immune ability of the host

    Institute of Scientific and Technical Information of China (English)

    CHENG Ying-xin; LI Fei; LU Jia-you; LI Mei; DU Peng; XU Gui-lian; FENG Hua

    2011-01-01

    Background It is generally accepted that gliomas are the most common primary brain tumors with poor prognosis. We aimed to explore the relationship of the immunity of the central nervous system and the genesis and development of glioma. Methods G422 glioma was implanted in the brain of BALB/c mice (immuno-competent mice), nude mice (T cell related immuno-deficient) and complement C3 knock-out mice (complement C3 related immunodeficient). The survival time of the host, growth and histopathology of the tumor, and concentrations of tumor necrosis factor-α (TNF-α) and interferon-γ (INF-γ) in tumor tissues were assessed.Results Tumor spheres were formed in all mice after injection, and glial fibrillary acidic protein (GFAP) positive staining of the cells declared their glioma origin. The longest median survival time of (44.3±6.0) days was found in BALB/c mice, followed by (24.8±5.2) days in nude mice and the shortest (18.6±5.8) days in complement C3 knock-out mice. Accordingly, the growth of the tumor was fastest in complement C3 knock-out mice, followed by the nude mice and slowest in the BALB/c mice. Although the proportions of infiltrating CD68+ lymphocytes in tumor tissues showed no significant difference (P>0.05), TNF-a level in the nude and C3 knock-out mice, (28.11±4.86) μmol/L and (22.87±6.36) μmol/L respectively, were significantly lower (P<0.01) than that in the BALB/c mice, which was (230.21±39.17) μmol/L. The INF-γ level was highest in the BALB/c mice ((180.76±29.19) μmol/L), followed by the nude mice ((113.46±23.76) μmol/L) and then the C3 knock-out mice ((16.84±4.45) μmol/L).Conclusions The G422 glioma implanted in the brains of mice with different immune ability would be a useful model for studying the relationship of the immune system and tumor in the central nervous system. Furthermore, the T cells and complement C3 compartments of the immune response may affect the growth of implanted tumors and inflammatory factors such as TNF

  6. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation

    DEFF Research Database (Denmark)

    Wallentin, Mikkel; Skakkebæk, Anne; Bojesen, Anders

    2016-01-01

    with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop) or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups...

  7. Cognitive improvement following transvenous adipose-derived mesenchymal stem cell transplantation in a rat model of traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Dongfei Li; Chun Yang; Rongmei Qu; Huiying Yang; Meichun Yu; Hui Tao; Jingxing Dai; Lin Yuan

    2011-01-01

    The effects of adipose-derived mesenchymal stem cell (ADMSC) transplantation for the repair of traumatic brain injury remain poorly understood. The present study observed neurological functional changes in a rat model of traumatic brain injury following ADMSC transplantation via the tail vein.Cell transplants were observed in injured cerebral cortex, and expression of brain-derived nerve growth factor was significantly increased in the injured hippocampus following transplantation. Results demonstrated that transvenous ADMSC transplants migrated to the injured cerebral cortex and significantly improved cognitive function.

  8. Development of an implantable wireless ECoG 128ch recording device for clinical brain machine interface.

    Science.gov (United States)

    Matsushita, Kojiro; Hirata, Masayuki; Suzuki, Takafumi; Ando, Hiroshi; Ota, Yuki; Sato, Fumihiro; Morris, Shyne; Yoshida, Takeshi; Matsuki, Hidetoshi; Yoshimine, Toshiki

    2013-01-01

    Brain Machine Interface (BMI) is a system that assumes user's intention by analyzing user's brain activities and control devices with the assumed intention. It is considered as one of prospective tools to enhance paralyzed patients' quality of life. In our group, we especially focus on ECoG (electro-corti-gram)-BMI, which requires surgery to place electrodes on the cortex. We try to implant all the devices within the patient's head and abdomen and to transmit the data and power wirelessly. Our device consists of 5 parts: (1) High-density multi-electrodes with a 3D shaped sheet fitting to the individual brain surface to effectively record the ECoG signals; (2) A small circuit board with two integrated circuit chips functioning 128 [ch] analogue amplifiers and A/D converters for ECoG signals; (3) A Wifi data communication & control circuit with the target PC; (4) A non-contact power supply transmitting electrical power minimum 400[mW] to the device 20[mm] away. We developed those devices, integrated them, and, investigated the performance.

  9. Current status and correlated issues on cochlear implantation

    Institute of Scientific and Technical Information of China (English)

    CAO Ke-li; WANG Lin-e

    2006-01-01

    @@ Cochlear implant is a biomedical device, which can directly stimulate the auditory nerve pass-by the damaged hair cell to recover and rebuild the hearing of deaf people. The implant can also stimulate the auditory brainstem and cortex in patients whose auditory nerve is not accessible because of acoustic tumors. Cochlear implantation can make the patients generate electrical hearing (artificial hearing).The artificial hearing can recover,improve or rebuild the hearing of deaf people through electrical stimulus.

  10. Brain stem death as the vital determinant for resumption of spontaneous circulation after cardiac arrest in rats.

    Directory of Open Access Journals (Sweden)

    Alice Y W Chang

    Full Text Available BACKGROUND: Spontaneous circulation returns to less than half of adult cardiac arrest victims who received in-hospital resuscitation. One clue for this disheartening outcome arises from the prognosis that asystole invariably takes place, after a time lag, on diagnosis of brain stem death. The designation of brain stem death as the point of no return further suggests that permanent impairment of the brain stem cardiovascular regulatory machinery precedes death. It follows that a crucial determinant for successful revival of an arrested heart is that spontaneous circulation must resume before brain stem death commences. Here, we evaluated the hypothesis that maintained functional integrity of the rostral ventrolateral medulla (RVLM, a neural substrate that is intimately related to brain stem death and central circulatory regulation, holds the key to the vital time-window between cardiac arrest and resumption of spontaneous circulation. METHODOLOGY/PRINCIPAL FINDINGS: An animal model of brain stem death employing the pesticide mevinphos as the experimental insult in Sprague-Dawley rats was used. Intravenous administration of lethal doses of mevinphos elicited an abrupt cardiac arrest, accompanied by elevated systemic arterial pressure and anoxia, augmented neuronal excitability and enhanced microvascular perfusion in RVLM. This period represents the vital time-window between cardiac arrest and resumption of spontaneous circulation in our experimental model. Animals with restored spontaneous circulation exhibited maintained neuronal functionality in RVLM beyond this critical time-window, alongside resumption of baseline tissue oxygen and enhancement of local blood flow. Intriguingly, animals that subsequently died manifested sustained anoxia, diminished local blood flow, depressed mitochondrial electron transport activities and reduced ATP production, leading to necrotic cell death in RVLM. That amelioration of mitochondrial dysfunction and

  11. Modeling learning in brain stem and cerebellar sites responsible for VOR plasticity

    Science.gov (United States)

    Quinn, K. J.; Didier, A. J.; Baker, J. F.; Peterson, B. W.

    1998-01-01

    A simple model of vestibuloocular reflex (VOR) function was used to analyze several hypotheses currently held concerning the characteristics of VOR plasticity. The network included a direct vestibular pathway and an indirect path via the cerebellum. An optimization analysis of this model suggests that regulation of brain stem sites is critical for the proper modification of VOR gain. A more physiologically plausible learning rule was also applied to this network. Analysis of these simulation results suggests that the preferred error correction signal controlling gain modification of the VOR is the direct output of the accessory optic system (AOS) to the vestibular nuclei vs. a signal relayed through the cerebellum via floccular Purkinje cells. The potential anatomical and physiological basis for this conclusion is discussed, in relation to our current understanding of the latency of the adapted VOR response.

  12. Control of Outer Radial Glial Stem Cell Mitosis in the Human Brain

    Directory of Open Access Journals (Sweden)

    Bridget E.L. Ostrem

    2014-08-01

    Full Text Available Evolutionary expansion of the human neocortex is partially attributed to a relative abundance of neural stem cells in the fetal brain called outer radial glia (oRG. oRG cells display a characteristic division mode, mitotic somal translocation (MST, in which the soma rapidly translocates toward the cortical plate immediately prior to cytokinesis. MST may be essential for progenitor zone expansion, but the mechanism of MST is unknown, hindering exploration of its function in development and disease. Here, we show that MST requires activation of the Rho effector ROCK and nonmuscle myosin II, but not intact microtubules, centrosomal translocation into the leading process, or calcium influx. MST is independent of mitosis and distinct from interkinetic nuclear migration and saltatory migration. Our findings suggest that disrupted MST may underlie neurodevelopmental diseases affecting the Rho-ROCK-myosin pathway and provide a foundation for future exploration of the role of MST in neocortical development, evolution, and disease.

  13. [Diagnostic significance of the spinal-brain stem polysynaptic reflex and the period of inhibition].

    Science.gov (United States)

    Ivanichev, G A

    1985-01-01

    Electrical stimulation of the radial nerve associated with voluntary contraction of the shoulder girdle inhibited bioelectrical activity not only in the muscles of the hypothenar but also in the proximal muscles. In resting muscles, such stimulation elicited a reflex response with a large latent period. With weak voluntary tension stimulation elicited a reflex response while in the presence of considerable contraction the reflex response merged with bioelectrical activity, with a clearly demonstrable subsequent period of inhibition. The current viewpoint about the antidromal blockade of the segmental motoneurons is debated. It is suggested that the polysynaptic reflex and the inhibition period are connected with the same level of realization -- the oral portions of the brain stem.

  14. Influence of leukoncephalopathy on the auditory and speech rehabilitation in patients with congenital hearing loss after cochlear implantation%脑白质病对先天性耳聋患儿人工耳蜗术后听觉言语恢复的影响

    Institute of Scientific and Technical Information of China (English)

    朱先锋; 张婧婧; 李金环; 马冰雪; 余永强; 钱银锋

    2015-01-01

    目的:探讨脑白质病对先天性耳聋患儿人工耳蜗术后听觉言语恢复的影响,为聋儿提供术前评价及术后恢复情况的评估。方法回顾性分析86例行人工耳蜗植入术的先天性耳聋患儿,年龄10月~6岁。术前行头颅常规 MRI 和内耳水成像,根据常规 MRI 表现分为脑白质病组和无脑白质病组,观察两组内耳畸形情况。术后半年采用听觉行为分级标准(CAP)和言语可懂度分级标准(SIR)对两组患儿的听力及言语恢复水平分别评分,并进行统计学分析比较。结果86例患者中22例存在脑白质病变,其中2例伴有内耳畸形;64例无脑白质病变,其中26例伴有内耳畸形。术后半年,脑白质病组 CAP 和 SIR 评分分别为(3.95±1.00)和(2.05±0.72),无脑白质病组则分别为(5.72±1.31)和(3.08±0.74),两组间差异显著。结论脑白质病是先天性耳聋患儿人工耳蜗植入后听觉感知及言语效果恢复的不利因素。%Objective To investigate the influence of leukoncephalopathy on the auditory and speech rehabilitation in patients with con-genital hearing loss after cochlear implantation,so as to define preoperative assessment and postoperative follow-up.Methods Eighty-six patients with congenital hearing loss performed with brain conventional MR imaging and inner ear hydrography before cochlear im-plantation,ages form ten months to six years.The patients were assigned into leukoncephalopathy group and non-leukoncephalopathy group according to the appearance on conventional MR images,and the malformation of inner ear was recorded.The hearing and speech recovery level was rated by using auditory behavior grading standards (CAP)and speech intelligibility grading standards (SIR)postop-eration half a year,which were compared between two groups.Results Twenty-two patients had leukoncephalopathy,among whom two cases had inner ear malformation

  15. An in vivo-like tumor stem cell-related glioblastoma in vitro model for drug discovery

    DEFF Research Database (Denmark)

    Jensen, Stine Skov; Aaberg-Jessen, Charlotte; Nørregaard, Annette

    the effects of new drugs on tumor cells including tumor stem cells. Implantation of glioblastoma cells into organotypic brain slice cultures has previously been published as a model system, but not using a stem cell favourable environment. Organotypic corticostriatal rat brain slice cultures were prepared......The discovery of tumor stem cells being highly resistant against therapy makes new demands to model systems suitable for evaluation of the effects of new drugs on tumor stem cells. The aim of the present study was therefore to develop an in vivo-like in vitro glioblastoma model for testing...... and cultured in a serum containing medium replaced after three days with a serum-free stem cell medium. Thereafter fluorescent DiI labelled glioblastoma spheroids from the cell line U87 and the tumor stem cell line SJ-1 established in our laboratory were implanted into the brain slices between cortex...

  16. Behavioral determination of stimulus pair discrimination of auditory acoustic and electrical stimuli using a classical conditioning and heart-rate approach.

    Science.gov (United States)

    Morgan, Simeon J; Paolini, Antonio G

    2012-06-06

    Acute animal preparations have been used in research prospectively investigating electrode designs and stimulation techniques for integration into neural auditory prostheses, such as auditory brainstem implants and auditory midbrain implants. While acute experiments can give initial insight to the effectiveness of the implant, testing the chronically implanted and awake animals provides the advantage of examining the psychophysical properties of the sensations induced using implanted devices. Several techniques such as reward-based operant conditioning, conditioned avoidance, or classical fear conditioning have been used to provide behavioral confirmation of detection of a relevant stimulus attribute. Selection of a technique involves balancing aspects including time efficiency (often poor in reward-based approaches), the ability to test a plurality of stimulus attributes simultaneously (limited in conditioned avoidance), and measure reliability of repeated stimuli (a potential constraint when physiological measures are employed). Here, a classical fear conditioning behavioral method is presented which may be used to simultaneously test both detection of a stimulus, and discrimination between two stimuli. Heart-rate is used as a measure of fear response, which reduces or eliminates the requirement for time-consuming video coding for freeze behaviour or other such measures (although such measures could be included to provide convergent evidence). Animals were conditioned using these techniques in three 2-hour conditioning sessions, each providing 48 stimulus trials. Subsequent 48-trial testing sessions were then used to test for detection of each stimulus in presented pairs, and test discrimination between the member stimuli of each pair. This behavioral method is presented in the context of its utilisation in auditory prosthetic research. The implantation of electrocardiogram telemetry devices is shown. Subsequent implantation of brain electrodes into the Cochlear

  17. Bioenergetics failure and oxidative stress in brain stem mediates cardiovascular collapse associated with fatal methamphetamine intoxication.

    Directory of Open Access Journals (Sweden)

    Faith C H Li

    Full Text Available BACKGROUND: Whereas sudden death, most often associated with cardiovascular collapse, occurs in abusers of the psychostimulant methamphetamine (METH, the underlying mechanism is much less understood. The demonstration that successful resuscitation of an arrested heart depends on maintained functionality of the rostral ventrolateral medulla (RVLM, which is responsible for the maintenance of stable blood pressure, suggests that failure of brain stem cardiovascular regulation, rather than the heart, holds the key to cardiovascular collapse. We tested the hypothesis that cessation of brain stem cardiovascular regulation because of a loss of functionality in RVLM mediated by bioenergetics failure and oxidative stress underlies the cardiovascular collapse elicited by lethal doses of METH. METHODOLOGY/PRINCIPAL FINDINGS: Survival rate, cardiovascular responses and biochemical or morphological changes in RVLM induced by intravenous administration of METH in Sprague-Dawley rats were investigated. High doses of METH induced significant mortality within 20 min that paralleled concomitant the collapse of arterial pressure or heart rate and loss of functionality in RVLM. There were concurrent increases in the concentration of METH in serum and ventrolateral medulla, along with tissue anoxia, cessation of microvascular perfusion and necrotic cell death in RVLM. Furthermore, mitochondrial respiratory chain enzyme activity or electron transport capacity and ATP production in RVLM were reduced, and mitochondria-derived superoxide anion level was augmented. All those detrimental physiological and biochemical events were reversed on microinjection into RVLM of a mobile electron carrier in the mitochondrial respiratory chain, coenzyme Q10; a mitochondria-targeted antioxidant and superoxide anion scavenger, Mito-TEMPO; or an oxidative stress-induced necrotic cell death inhibitor, IM-54. CONCLUSION: We conclude that sustained anoxia and cessation of local blood flow

  18. Differential Responses of Human Fetal Brain Neural Stem Cells to Zika Virus Infection

    Directory of Open Access Journals (Sweden)

    Erica L. McGrath

    2017-03-01

    Full Text Available Zika virus (ZIKV infection causes microcephaly in a subset of infants born to infected pregnant mothers. It is unknown whether human individual differences contribute to differential susceptibility of ZIKV-related neuropathology. Here, we use an Asian-lineage ZIKV strain, isolated from the 2015 Mexican outbreak (Mex1-7, to infect primary human neural stem cells (hNSCs originally derived from three individual fetal brains. All three strains of hNSCs exhibited similar rates of Mex1-7 infection and reduced proliferation. However, Mex1-7 decreased neuronal differentiation in only two of the three stem cell strains. Correspondingly, ZIKA-mediated transcriptome alterations were similar in these two strains but significantly different from that of the third strain with no ZIKV-induced neuronal reduction. This study thus confirms that an Asian-lineage ZIKV strain infects primary hNSCs and demonstrates a cell-strain-dependent response of hNSCs to ZIKV infection.

  19. Imaging long-term fate of intramyocardially implanted mesenchymal stem cells in a porcine myocardial infarction model.

    Directory of Open Access Journals (Sweden)

    Emerson C Perin

    Full Text Available The long-term fate of stem cells after intramyocardial delivery is unknown. We used noninvasive, repetitive PET/CT imaging with [(18F]FEAU to monitor the long-term (up to 5 months spatial-temporal dynamics of MSCs retrovirally transduced with the sr39HSV1-tk gene (sr39HSV1-tk-MSC and implanted intramyocardially in pigs with induced acute myocardial infarction. Repetitive [(18F]FEAU PET/CT revealed a biphasic pattern of sr39HSV1-tk-MSC dynamics; cell proliferation peaked at 33-35 days after injection, in periinfarct regions and the major cardiac lymphatic vessels and lymph nodes. The sr39HSV1-tk-MSC-associated [(18F]FEAU signals gradually decreased thereafter. Cardiac lymphography studies using PG-Gd-NIRF813 contrast for MRI and near-infrared fluorescence imaging showed rapid clearance of the contrast from the site of intramyocardial injection through the subepicardial lymphatic network into the lymphatic vessels and periaortic lymph nodes. Immunohistochemical analysis of cardiac tissue obtained at 35 and 150 days demonstrated several types of sr39HSV1-tk expressing cells, including fibro-myoblasts, lymphovascular cells, and microvascular and arterial endothelium. In summary, this study demonstrated the feasibility and sensitivity of [(18F]FEAU PET/CT imaging for long-term, in-vivo monitoring (up to 5 months of the fate of intramyocardially injected sr39HSV1-tk-MSC cells. Intramyocardially transplanted MSCs appear to integrate into the lymphatic endothelium and may help improve myocardial lymphatic system function after MI.

  20. Progesterone promotes neuronal differentiation of human umbilical cord mesenchymal stem cells in culture conditions that mimic the brain microenvironment

    Institute of Scientific and Technical Information of China (English)

    Xianying Wang; Honghai Wu; Gai Xue; Yanning Hou

    2012-01-01

    In this study, human umbilical cord mesenchymal stem cells from full-term neonates born by vaginal delivery were cultured in medium containing 150 mg/mL of brain tissue extracts from Sprague-Dawley rats (to mimic the brain microenvironment). Immunocytochemical analysis demonstrated that the cells differentiated into neuron-like cells. To evaluate the effects of progesterone as a neurosteroid on the neuronal differentiation of human umbilical cord mesenchymal stem cells, we cultured the cells in medium containing progesterone (0.1, 1, 10 μM) in addition to brain tissue extracts. Reverse transcription-PCR and flow cytometric analysis of neuron specific enolase-positive cells revealed that the percentages of these cells increased significantly following progesterone treatment, with the optimal progesterone concentration for neuron-like differentiation being 1 μM. These results suggest that progesterone can enhance the neuronal differentiation of human umbilical cord mesenchymal stem cells in culture medium containing brain tissue extracts to mimic the brain microenvironment.

  1. Therapeutics with SPION-labeled stem cells for the main diseases related to brain aging: a systematic review

    Directory of Open Access Journals (Sweden)

    Alvarim LT

    2014-08-01

    Full Text Available Larissa T Alvarim,1,3,* Leopoldo P Nucci,2,* Javier B Mamani,1 Luciana C Marti,1 Marina F Aguiar,1,2 Helio R Silva,1,3 Gisele S Silva,1 Mariana P Nucci-da-Silva,4 Elaine A DelBel,5,6 Lionel F Gamarra1–31Hospital Israelita Albert Einstein, São Paulo, Brazil; 2Universidade Federal de São Paulo, UNIFESP, São Paulo, Brazil; 3Faculdade de Ciências Médicas da Santa Casa de São Paulo, São Paulo, Brazil; 4Departamento de Radiologia, Hospital das Clínicas, Universidade de São Paulo, Brazil; 5Universidade de São Paulo-Faculdade de Odontologia de Ribeirão Preto, São Paulo, Brazil; 6NAPNA- Núcleo de Apoio a Pesquisa em Neurociências Aplicadas, São Paulo, Brazil*These authors contributed equally to this workAbstract: The increase in clinical trials assessing the efficacy of cell therapy for structural and functional regeneration of the nervous system in diseases related to the aging brain is well known. However, the results are inconclusive as to the best cell type to be used or the best methodology for the homing of these stem cells. This systematic review analyzed published data on SPION (superparamagnetic iron oxide nanoparticle-labeled stem cells as a therapy for brain diseases, such as ischemic stroke, Parkinson’s disease, amyotrophic lateral sclerosis, and dementia. This review highlights the therapeutic role of stem cells in reversing the aging process and the pathophysiology of brain aging, as well as emphasizing nanotechnology as an important tool to monitor stem cell migration in affected regions of the brain.Keywords: iron oxide, dementia, stem cell, stroke, Parkinson’s disease, sclerosis disease, brain aging

  2. Functional Near-Infrared Spectroscopy Brain Imaging Investigation of Phonological Awareness and Passage Comprehension Abilities in Adult Recipients of Cochlear Implants

    Science.gov (United States)

    Bisconti, Silvia; Shulkin, Masha; Hu, Xiaosu; Basura, Gregory J.; Kileny, Paul R.; Kovelman, Ioulia

    2016-01-01

    Purpose: The aim of this study was to examine how the brains of individuals with cochlear implants (CIs) respond to spoken language tasks that underlie successful language acquisition and processing. Method: During functional near-infrared spectroscopy imaging, CI recipients with hearing impairment (n = 10, mean age: 52.7 ± 17.3 years) and…

  3. Decreases in energy and increases in phase locking of event-related oscillations to auditory stimuli occur during adolescence in human and rodent brain.

    Science.gov (United States)

    Ehlers, Cindy L; Wills, Derek N; Desikan, Anita; Phillips, Evelyn; Havstad, James

    2014-01-01

    Synchrony of phase (phase locking) of event-related oscillations (EROs) within and between different brain areas has been suggested to reflect communication exchange between neural networks and as such may be a sensitive and translational measure of changes in brain remodeling that occur during adolescence. This study sought to investigate developmental changes in EROs using a similar auditory event-related potential (ERP) paradigm in both rats and humans. Energy and phase variability of EROs collected from 38 young adult men (aged 18-25 years), 33 periadolescent boys (aged 10-14 years), 15 male periadolescent rats [at postnatal day (PD) 36] and 19 male adult rats (at PD103) were investigated. Three channels of ERP data (frontal cortex, central cortex and parietal cortex) were collected from the humans using an 'oddball plus noise' paradigm that was presented under passive (no behavioral response required) conditions in the periadolescents and under active conditions (where each subject was instructed to depress a counter each time he detected an infrequent target tone) in adults and adolescents. ERPs were recorded in rats using only the passive paradigm. In order to compare the tasks used in rats to those used in humans, we first studied whether three ERO measures [energy, phase locking index (PLI) within an electrode site and phase difference locking index (PDLI) between different electrode sites] differentiated the 'active' from 'passive' ERP tasks. Secondly, we explored our main question of whether the three ERO measures differentiated adults from periadolescents in a similar manner in both humans and rats. No significant changes were found in measures of ERO energy between the active and passive tasks in the periadolescent human participants. There was a smaller but significant increase in PLI but not PDLI as a function of active task requirements. Developmental differences were found in energy, PLI and PDLI values between the periadolescents and adults in

  4. Studies on Auditory and Vestibular End Organs and Brain Stem Nuclei. [inner ear damage and hearing defects

    Science.gov (United States)

    Ades, H. W.

    1974-01-01

    Cats were exposed to tones of 125, 1000, 2000, and 4000 Hz at sound pressure levels in the range 120 to 157.5 db, and for durations of one hour (1000, 2000, 4000 Hz) or four hours (125 Hz). Pure tone audiograms were obtained for each animal before and after exposure. Cochleas of animals were examined by phase-contrast microscopy. Extent of inner ear damage and range of frequencies for which hearing loss occurred increased as exposure tone was decreased in frequency. For example, exposure to 4000 Hz produced damage in a restricted region of the cochlea and hearing loss for a relatively narrow range of frequencies; exposure to 125 Hz produced wide-spread inner ear damage and hearing loss throughout the frequency range 125 to 6000 Hz.

  5. A Case of Primary Central Nervous System Lymphoma Located at Brain Stem in a Child

    Science.gov (United States)

    Kim, Jinho

    2016-01-01

    Primary central nervous system lymphoma (PCNSL) is an extranodal Non-Hodgkin's lymphoma that is confined to the brain, eyes, and/or leptomeninges without evidence of a systemic primary tumor. Although the tumor can affect all age groups, it is rare in childhood; thus, its incidence and prognosis in children have not been well defined and the best treatment strategy remains unclear. A nine-year old presented at our department with complaints of diplopia, dizziness, dysarthria, and right side hemiparesis. Magnetic resonance image suggested a diffuse brain stem glioma with infiltration into the right cerebellar peduncle. The patient was surgically treated by craniotomy and frameless stereotactic-guided biopsy, and unexpectedly, the histopathology of the mass was consistent with diffuse large B cell lymphoma, and immunohistochemical staining revealed positivity for CD20 and CD79a. Accordingly, we performed a staging work-up for systemic lymphoma, but no evidence of lymphoma elsewhere in the body was obtained. In addition, she had a negative serologic finding for human immunodeficient virus, which confirmed the histopathological diagnosis of PCNSL. She was treated by radiosurgery at 12 Gy and subsequent adjuvant combination chemotherapy based on high dose methotrexate. Unfortunately, 10 months after the tissue-based diagnosis, she succumbed due to an acute hydrocephalic crisis. PMID:27867930

  6. Long-term asymmetric hearing affects cochlear implantation outcomes differently in adults with pre- and postlingual hearing loss.

    Science.gov (United States)

    Boisvert, Isabelle; McMahon, Catherine M; Dowell, Richard C; Lyxell, Björn

    2015-01-01

    In many countries, a single cochlear implant is offered as a treatment for a bilateral hearing loss. In cases where there is asymmetry in the amount of sound deprivation between the ears, there is a dilemma in choosing which ear should be implanted. In many clinics, the choice of ear has been guided by an assumption that the reorganisation of the auditory pathways caused by longer duration of deafness in one ear is associated with poorer implantation outcomes for that ear. This assumption, however, is mainly derived from studies of early childhood deafness. This study compared outcomes following implantation of the better or poorer ear in cases of long-term hearing asymmetries. Audiological records of 146 adults with bilateral hearing loss using a single hearing aid were reviewed. The unaided ear had 15 to 72 years of unaided severe to profound hearing loss before unilateral cochlear implantation. 98 received the implant in their long-term sound-deprived ear. A multiple regression analysis was conducted to assess the relative contribution of potential predictors to speech recognition performance after implantation. Duration of bilateral significant hearing loss and the presence of a prelingual hearing loss explained the majority of variance in speech recognition performance following cochlear implantation. For participants with postlingual hearing loss, similar outcomes were obtained by implanting either ear. With prelingual hearing loss, poorer outcomes were obtained when implanting the long-term sound-deprived ear, but the duration of the sound deprivation in the implanted ear did not reliably predict outcomes. Contrary to an apparent clinical consensus, duration of sound deprivation in one ear has limited value in predicting speech recognition outcomes of cochlear implantation in that ear. Outcomes of cochlear implantation are more closely related to the period of time for which the brain is deprived of auditory stimulation from both ears.

  7. Regional Susceptibility to Domoic Acid in Primary Astrocyte Cells Cultured from the Brain Stem and Hippocampus

    Directory of Open Access Journals (Sweden)

    Olga M. Pulido

    2008-02-01

    Full Text Available Domoic acid is a marine biotoxin associated with harmful algal blooms and is the causative agent of amnesic shellfish poisoning in marine animals and humans. It is also an excitatory amino acid analog to glutamate and kainic acid which acts through glutamate receptors eliciting a very rapid and potent neurotoxic response. The hippocampus, among other brain regions, has been identified as a specific target site having high sensitivity to DOM toxicity. Histopathology evidence indicates that in addition to neurons, the astrocytes were also injured. Electron microscopy data reported in this study further supports the light microscopy findings. Furthermore, the effect of DOM was confirmed by culturing primary astrocytes from the hippocampus and the brain stem and subsequently exposing them to domoic acid. The RNA was extracted and used for biomarker analysis. The biomarker analysis was done for the early response genes including c-fos, c-jun, c-myc, Hsp-72; specific marker for the astrocytes- GFAP and the glutamate receptors including GluR 2, NMDAR 1, NMDAR 2A and B. Although, the astrocyte-GFAP and c-fos were not affected, c-jun and GluR 2 were down-regulated. The microarray analysis revealed that the chemokines / cytokines, tyrosine kinases (Trk, and apoptotic genes were altered. The chemokines that were up-regulated included - IL1-a, IL-1B, IL-6, the small inducible cytokine, interferon protein IP-10, CXC chemokine LIX, and IGF binding proteins. The Bax, Bcl-2, Trk A and Trk B were all downregulated. Interestingly, only the hippocampal astrocytes were affected. Our findings suggest that astrocytes may present a possible target for pharmacological interventions for the prevention and treatment of amnesic shellfish poisoning and for other brain pathologies involving excitotoxicity

  8. Brain implants for substituting lost motor function: state of the art and potential impact on the lives of motor-impaired seniors.

    Science.gov (United States)

    Ramsey, N F; Aarnoutse, E J; Vansteensel, M J

    2014-01-01

    Recent scientific achievements bring the concept of neural prosthetics for reinstating lost motor function closer to medical application. Current research involves severely paralyzed people under the age of 65, but implications for seniors with stroke or trauma-induced impairments are clearly on the horizon. Demographic changes will lead to a shortage of personnel to care for an increasing population of senior citizens, threatening maintenance of an acceptable level of care and urging ways for people to live longer at their home independent from personal assistance. This is particularly challenging when people suffer from disabilities such as partial paralysis after stroke or trauma, where daily personal assistance is required. For some of these people, neural prosthetics can reinstate some lost motor function and/or lost communication, thereby increasing independence and possibly quality of life. In this viewpoint article, we present the state of the art in decoding brain activity in the service of brain-computer interfacing. Although some noninvasive applications produce good results, we focus on brain implants that benefit from better quality brain signals. Fully implantable neural prostheses for home use are not available yet, but clinical trials are being prepared. More sophisticated systems are expected to follow in the years to come, with capabilities of interest for less severe paralysis. Eventually the combination of smart robotics and brain implants is expected to enable people to interact well enough with their environment to live an independent life in spite of motor disabilities.

  9. Recent advances in the involvement of long non-coding RNAs in neural stem cell biology and brain pathophysiology

    Directory of Open Access Journals (Sweden)

    Daphne eAntoniou

    2014-04-01

    Full Text Available Exploration of non-coding genome has recently uncovered a growing list of formerly unknown regulatory long non-coding RNAs (lncRNAs with important functions in stem cell pluripotency, development and homeostasis of several tissues. Although thousands of lncRNAs are expressed in mammalian brain in a highly patterned manner, their roles in brain development have just begun to emerge. Recent data suggest key roles for these molecules in gene regulatory networks controlling neuronal and glial cell differentiation. Analysis of the genomic distribution of genes encoding for lncRNAs indicates a physical association of these regulatory RNAs with transcription factors (TFs with well-established roles in neural differentiation, suggesting that lncRNAs and TFs may form coherent regulatory networks with important functions in neural stem cells (NSCs. Additionally, many studies show that lncRNAs are involved in the pathophysiology of brain-related diseases/disorders. Here we discuss these observations and investigate the links between lncRNAs, brain development and brain-related diseases. Understanding the functions of lncRNAs in NSCs and brain organogenesis could revolutionize the basic principles of developmental biology and neuroscience.

  10. Prolonged osteogenesis from human mesenchymal stem cells implanted in immunodeficient mice by using coralline hydroxyapatite incorporating rhBMP2 microspheres.

    Science.gov (United States)

    Fu, Kun; Xu, Qingguo; Czernuszka, Jan; McKenna, Charles E; Ebetino, Frank H; Russell, R Graham G; Triffitt, James T; Xia, Zhidao

    2010-03-15

    The local environment plays an important role in osteogenic tissue regeneration. Our previous studies have shown that xenogenic transplantation of human mesenchymal stem cells (hMSCs) alone into immunodeficient mice did not result in long-term bone formation. This study investigates whether bone formation can be prolonged by incorporating human mesenchymal stem cells in mineralized scaffolds together with controlled delivery of a growth factor, BMP2. A composite of coralline hydroxyapatite (CHA) with poly(lactic-co-glycolic acid) (PLGA)-encapsulated rhBMP2 was incorporated with hMSCs in vitro. After 2 weeks in vitro culture the constructs were implanted subcutaneously in CB17 scid beige mice and harvested 10 weeks after implantation. The mineralized tissues were stained by using a fluorescent marker, 5FAM-risedronate, followed by observation with fluorescence microscopy, histology, histomorphometry, mouse-anti-human vimentin immunohistochemistry, and scanning microscopy. The results showed that compared with control materials in which only fibrous tissue formed following implantation of coralline scaffolds, bone-like tissue formed within the CHA composite containing PLGA encapsulated rhBMP2 and hMSCs for up to 10 weeks after implantation. Human cells, identified by the human vimentin-specific monoclonal antibody were seen within the bone-like tissue. In conclusion, incorporation of hMSCs into CHA with controlled delivery of BMP showed prolonged bone formation in immunodeficient mice. Further research is required to optimize the growth factor delivery system and to understand the underlying cellular and molecular mechanisms involved.

  11. Brain changes in Alzheimer's disease patients with implanted encapsulated cells releasing nerve growth factor.

    Science.gov (United States)

    Ferreira, Daniel; Westman, Eric; Eyjolfsdottir, Helga; Almqvist, Per; Lind, Göran; Linderoth, Bengt; Seiger, Ake; Blennow, Kaj; Karami, Azadeh; Darreh-Shori, Taher; Wiberg, Maria; Simmons, Andrew; Wahlund, Lars-Olof; Wahlberg, Lars; Eriksdotter, Maria

    2015-01-01

    New therapies with disease-modifying effects are urgently needed for treating Alzheimer's disease (AD). Nerve growth factor (NGF) protein has demonstrated regenerative and neuroprotective effects on basal forebrain cholinergic neurons in animal studies. In addition, AD patients treated with NGF have previously shown improved cognition, EEG activity, nicotinic binding, and glucose metabolism. However, no study to date has analyzed brain atrophy in patients treated with NGF producing cells. In this study we present MRI results of the first clinical trial in patients with AD using encapsulated NGF biodelivery to the basal forebrain. Six AD patients received the treatment during twelve months. Patients were grouped as responders and non-responders according to their twelve-months change in MMSE. Normative values were created from 131 AD patients from ADNI, selecting 36 age- and MMSE-matched patients for interpreting the longitudinal changes in MMSE and brain atrophy. Results at baseline indicated that responders showed better clinical status and less pathological levels of cerebrospinal fluid (CSF) Aβ1-42. However, they showed more brain atrophy, and neuronal degeneration as evidenced by higher CSF levels of T-tau and neurofilaments. At follow-up, responders showed less brain shrinkage and better progression in the clinical variables and CSF biomarkers. Noteworthy, two responders showed less brain shrinkage than the normative ADNI group. These results together with previous evidence supports the idea that encapsulated biodelivery of NGF might have the potential to become a new treatment strategy for AD with both symptomatic and disease-modifying effects.

  12. Adenovirus-mediated human brain-derived neurotrophic factor gene-modified bone marrow mesenchymal stem cell transplantation for spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    Changsheng Wang; Jianhua Lin; Chaoyang Wu; Rongsheng Chen

    2011-01-01

    Rat bone marrow mesenchymal stem cells expressing brain-derived neurotrophic factor were successfully obtained using a gene transfection method, then intravenously transplanted into rats with spinal cord injury. At 1, 3, and 5 weeks after transplantation, the expression of ??brain-derived neurotrophic factor and neurofilament-200 was upregulated in the injured spinal cord, spinal cord injury was alleviated, and Basso-Beattie-Bresnahan scores of hindlimb motor function were significantly increased. This evidence suggested that intravenous transplantation of adenovirus- mediated brain-derived neurotrophic factor gene-modified rat bone marrow mesenchymal stem cells could play a dual role, simultaneously providing neural stem cells and neurotrophic factors.

  13. Drosophila Brat and Human Ortholog TRIM3 Maintain Stem Cell Equilibrium and Suppress Brain Tumorigenesis by Attenuating Notch Nuclear Transport.

    Science.gov (United States)

    Mukherjee, Subhas; Tucker-Burden, Carol; Zhang, Changming; Moberg, Kenneth; Read, Renee; Hadjipanayis, Costas; Brat, Daniel J

    2016-04-15

    Cancer stem cells exert enormous influence on neoplastic behavior, in part by governing asymmetric cell division and the balance between self-renewal and multipotent differentiation. Growth is favored by deregulated stem cell division, which enhances the self-renewing population and diminishes the differentiation program. Mutation of a single gene in Drosophila, Brain Tumor (Brat), leads to disrupted asymmetric cell division resulting in dramatic neoplastic proliferation of neuroblasts and massive larval brain overgrowth. To uncover the mechanisms relevant to deregulated cell division in human glioma stem cells, we first developed a novel adult Drosophila brain tumor model using brat-RNAi driven by the neuroblast-specific promoter inscuteable Suppressing Brat in this population led to the accumulation of actively proliferating neuroblasts and a lethal brain tumor phenotype. brat-RNAi caused upregulation of Notch signaling, a node critical for self-renewal, by increasing protein expression and enhancing nuclear transport of Notch intracellular domain (NICD). In human glioblastoma, we demonstrated that the human ortholog of Drosophila Brat, tripartite motif-containing protein 3 (TRIM3), similarly suppressed NOTCH1 signaling and markedly attenuated the stem cell component. We also found that TRIM3 suppressed nuclear transport of active NOTCH1 (NICD) in glioblastoma and demonstrated that these effects are mediated by direct binding of TRIM3 to the Importin complex. Together, our results support a novel role for Brat/TRIM3 in maintaining stem cell equilibrium and suppressing tumor growth by regulating NICD nuclear transport. Cancer Res; 76(8); 2443-52. ©2016 AACR.

  14. Analysis of Auditory Perception Skills in Pre - lingual Deaf Children with Inner Ear Malformation after Cochlear Implantation%内耳畸形语前聋患儿人工耳蜗植入术后听觉能力分析

    Institute of Scientific and Technical Information of China (English)

    陈秀兰; 秦兆冰; 张玉玲; 付凯辉

    2015-01-01

    Objective The aim of this study was to evaluate the outcomes of auditory perception skills after cochlear implantation in children with malformed inner ear and compare them with a group of congenitally deaf chil ‐dren implantees with a normal inner ear .Methods 21 children with inner ear malformation were retrospective stud‐ied .There were 9 cases with large vestibular aqueduct syndrome (LVAS) ,7 with Mondini abnormality ,5 with com‐mon cavity .The postoperative outcomes of these 21 cases were compared with 21 cases with normal inner ear struc‐ture .The outcomes of all the children after the surgery in 1 year were studied using the soundfield test in frequency ranging 0 .5 to 4 kHz and the auditory perception skills ,and the auditory perception skills consisted of natural envi‐ronmental sound recognition ,consonants recognition ,vowels recognition ,numeral recognition ,tone recognition , monosyllabe recognition ,disyllabe recognition ,trisyllabe recognition ,short sentences recognition ,selective hearing recognition .Results The results of soundfield test and auditory perception skills after cochlear implantation in 9 children with LVAS and 6 with Mondini abnormality had no significant difference (P > 0 .05) comparing with the control cases .Postoperative thresholds in soundfield test were 50 ~ 75 dB HL for 1 case with severe Mondini abnor‐mality ,the mean value of hearing ability score was 70 .5% ,and less than the results of control cases .Postoperative mean thresholds in soundfield test were 65 .26 ± 5 .13 dB HL for 5 cases with common cavity ,the hearing ability score was less than the results of control cases (P< 0 .05) .Conclusion The effect of rehabilitation had no difference between the children with LVAS and the cases with normal inner structure after cochlear implantation ,but was poo‐rer in children with severe Mondini abnormality and common cavity .It was necessary to evaluate the degree of mal‐formation of inner ear structure before

  15. Auditory short-term memory in the primate auditory cortex.

    Science.gov (United States)

    Scott, Brian H; Mishkin, Mortimer

    2016-06-01

    Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ׳working memory' bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive short-term memory (pSTM), is tractable to study in nonhuman primates, whose brain architecture and behavioral repertoire are comparable to our own. This review discusses recent advances in the behavioral and neurophysiological study of auditory memory with a focus on single-unit recordings from macaque monkeys performing delayed-match-to-sample (DMS) tasks. Monkeys appear to employ pSTM to solve these tasks, as evidenced by the impact of interfering stimuli on memory performance. In several regards, pSTM in monkeys resembles pitch memory in humans, and may engage similar neural mechanisms. Neural correlates of DMS performance have been observed throughout the auditory and prefrontal cortex, defining a network of areas supporting auditory STM with parallels to that supporting visual STM. These correlates include persistent neural firing, or a suppression of firing, during the delay period of the memory task, as well as suppression or (less commonly) enhancement of sensory responses when a sound is repeated as a ׳match' stimulus. Auditory STM is supported by a distributed temporo-frontal network in which sensitivity to stimulus history is an intrinsic feature of auditory processing. This article is part of a Special Issue entitled SI: Auditory working memory.

  16. Asymmetric excitatory synaptic dynamics underlie interaural time difference processing in the auditory system.

    Directory of Open Access Journals (Sweden)

    Pablo E Jercog

    Full Text Available Low-frequency sound localization depends on the neural computation of interaural time differences (ITD and relies on neurons in the auditory brain stem that integrate synaptic inputs delivered by the ipsi- and contralateral auditory pathways that start at the two ears. The first auditory neurons that respond selectively to ITD are found in the medial superior olivary nucleus (MSO. We identified a new mechanism for ITD coding using a brain slice preparation that preserves the binaural inputs to the MSO. There was an internal latency difference for the two excitatory pathways that would, if left uncompensated, position the ITD response function too far outside the physiological range to be useful for estimating ITD. We demonstrate, and support using a biophysically based computational model, that a bilateral asymmetry in excitatory post-synaptic potential (EPSP slopes provides a robust compensatory delay mechanism due to differential activation of low threshold potassium conductance on these inputs and permits MSO neurons to encode physiological ITDs. We suggest, more generally, that the dependence of spike probability on rate of depolarization, as in these auditory neurons, provides a mechanism for temporal order discrimination between EPSPs.

  17. Harmonic Training and the formation of pitch representation in a neural network model of the auditory brain

    Directory of Open Access Journals (Sweden)

    Nasir eAhmad

    2016-03-01

    Full Text Available Attempting to explain the perceptual qualities of pitch has proven to be, and remains, a difficult problem. The wide range of sounds which illicit pitch and a lack of agreement across neurophysiological studies on how pitch is encoded by the brain have made this attempt more difficult. In describing the potential neural mechanisms by which pitch may be processed, a number of neural networks have been proposed and implemented. However, no unsupervised neural networks with biologically accurate cochlear inputs have yet been demonstrated. This paper proposes a simplified system in which pitch representing neurons are easily produced under a highly biological setting. Purely unsupervised regimes of neural network learning are implemented and these prove to be sufficient in identifying the pitch of sounds with a variety of spectral profiles, including missing fundamental sounds.

  18. Metformin and Ara-a Effectively Suppress Brain Cancer by Targeting Cancer Stem/Progenitor Cells

    Science.gov (United States)

    Mouhieddine, Tarek H.; Nokkari, Amaly; Itani, Muhieddine M.; Chamaa, Farah; Bahmad, Hisham; Monzer, Alissar; El-Merahbi, Rabih; Daoud, Georges; Eid, Assaad; Kobeissy, Firas H.; Abou-Kheir, Wassim

    2015-01-01

    Background: Gliomas and neuroblastomas pose a great health burden worldwide with a poor and moderate prognosis, respectively. Many studies have tried to find effective treatments for these primary malignant brain tumors. Of interest, the AMP-activated protein kinase (AMPK) pathway was found to be associated with tumorigenesis and tumor survival, leading to many studies on AMPK drugs, especially Metformin, and their potential role as anti-cancer treatments. Cancer stem cells (CSCs) are a small population of slowly-dividing, treatment-resistant, undifferentiated cancer cells that are being discovered in a multitude of cancers. They are thought to be responsible for replenishing the tumor with highly proliferative cells and increasing the risk of recurrence. Methods: Metformin and 9-β-d-Arabinofuranosyl Adenine (Ara-a) were used to study the role of the AMPK pathway in vitro on U251 (glioblastoma) and SH-SY5Y (neuroblastoma) cell lines. Results: We found that both drugs are able to decrease the survival of U251 and SH-SY5Y cell lines in a 2D as well as a 3D culture model. Metformin and Ara-a significantly decreased the invasive ability of these cancer cell lines. Treatment with these drugs decreased the sphere-forming units (SFU) of U251 cells, with Ara-a being more efficient, signifying the extinction of the CSC population. However, if treatment is withdrawn before all SFUs are extinguished, the CSCs regain some of their sphere-forming capabilities in the case of Metformin but not Ara-a treatment. Conclusion: Metformin and Ara-a have proved to be effective in the treatment of glioblastomas and neuroblastomas, in vitro, by targeting their cancer stem/progenitor cell population, which prevents recurrence. PMID:26635517

  19. Metformin and Ara-a Effectively Suppress Brain Cancer by Targeting Cancer Stem/Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Tarek H. Mouhieddine

    2015-11-01

    Full Text Available Background: Gliomas and neuroblastomas pose a great health burden worldwide with a poor and moderate prognosis, respectively. Many studies have tried to find effective treatments for these primary malignant brain tumors. Of interest, the AMP-activated protein kinase (AMPK pathway was found to be associated with tumorigenesis and tumor survival, leading to many studies on AMPK drugs, especially Metformin, and their potential role as anti-cancer treatments. Cancer stem cells (CSCs are a small population of slowly-dividing, treatment-resistant, undifferentiated cancer cells that are being discovered in a multitude of cancers. They are thought to be responsible for replenishing the tumor with highly proliferative cells and increasing the risk of recurrence. Methods: Metformin and 9-β-d-Arabinofuranosyl Adenine (Ara-a were used to study the role of the AMPK pathway in vitro on U251 (glioblastoma and SHSY-5Y (neuroblastoma cell lines.Results: We found that both drugs are able to decrease the survival of U251 and SH-SY5Y cell lines in a 2D as well as a 3D culture model. Metformin and Ara-a significantly decreased the invasive ability of these cancer cell lines. Treatment with these drugs decreased the sphere-forming units (SFU of U251 cells, with Ara-a being more efficient, signifying the extinction of the CSC population. However, if treatment is withdrawn before all SFUs are extinguished, the CSCs regain some of their sphere-forming capabilities in the case of Metformin but not Ara-a treatment. Conclusion: Metformin and Ara-a have proved to be effective in the treatment of glioblastomas and neuroblastomas, in vitro, by targeting their cancer stem/progenitor cell population, which prevents recurrence.

  20. Is this a brain which I see before me? Modeling human neural development with pluripotent stem cells.

    Science.gov (United States)

    Suzuki, Ikuo K; Vanderhaeghen, Pierre

    2015-09-15

    The human brain is arguably the most complex structure among living organisms. However, the specific mechanisms leading to this complexity remain incompletely understood, primarily because of the poor experimental accessibility of the human embryonic brain. Over recent years, technologies based on pluripotent stem cells (PSCs) have been developed to generate neural cells of various types. While the translational potential of PSC technologies for disease modeling and/or cell replacement therapies is usually put forward as a rationale for their utility, they are also opening novel windows for direct observation and experimentation of the basic mechanisms of human brain development. PSC-based studies have revealed that a number of cardinal features of neural ontogenesis are remarkably conserved in human models, which can be studied in a reductionist fashion. They have also revealed species-specific features, which constitute attractive lines of investigation to elucidate the mechanisms underlying the development of the human brain, and its link with evolution.

  1. Comparison of tactile, auditory and visual modality for brain-computer interface use: A case study with a patient in the locked-in state

    Directory of Open Access Journals (Sweden)

    Tobias eKaufmann

    2013-07-01

    Full Text Available This paper describes a case study with a patient in the classic locked-in state, who currently has no means of independent communication. Following a user-centered approach, we investigated event-related potentials elicited in different modalities for use in brain-computer interface systems. Such systems could provide her with an alternative communication channel. To investigate the most viable modality for achieving BCI based communication, classic oddball paradigms (1 rare and 1 frequent stimulus, ratio 1:5 in the visual, auditory and tactile modality were conducted (2 runs per modality. Classifiers were built on one run and tested offline on another run (and vice versa. In these paradigms, the tactile modality was clearly superior to other modalities, displaying high offline accuracy even when classification was performed on single trials only. Consequently, we tested the tactile paradigm online and the patient successfully selected targets without any error. Furthermore, we investigated use of the visual or tactile modality for different BCI systems with more than two selection options. In the visual modality, several BCI paradigms were tested offline. Neither matrix-based nor so-called gaze-independent paradigms constituted a means of control. These results may thus question the gaze-independence of current gaze-independent approaches to BCI. A tactile four-choice BCI resulted in high offline classification accuracies. Yet, online use raised various issues. Although performance was clearly above chance, practical daily life use appeared unlikely when compared to other communication approaches (e.g. partner scanning. Our results emphasize the need for user-centered design in BCI development including identification of the best stimulus modality for a particular user. Finally, the paper discusses feasibility of EEG-based BCI systems for patients in classic locked-i