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Sample records for brainstem response abr

  1. Abnormal Auditory Brainstem Response (ABR Findings in a Near-Normal Hearing Child with Noonan Syndrome

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    Bahram Jalaei

    2017-01-01

    Full Text Available Introduction: Noonan syndrome (NS is a heterogeneous genetic disease that affects many parts of the body. It was named after Dr. Jacqueline Anne Noonan, a paediatric cardiologist.Case Report: We report audiological tests and auditory brainstem response (ABR findings in a 5-year old Malay boy with NS. Despite showing the marked signs of NS, the child could only produce a few meaningful words. Audiological tests found him to have bilateral mild conductive hearing loss at low frequencies. In ABR testing, despite having good waveform morphology, the results were atypical. Absolute latency of wave V was normal but interpeak latencies of wave’s I-V, I-II, II-III were prolonged. Interestingly, interpeak latency of waves III-V was abnormally shorter.Conclusion:Abnormal ABR results are possibly due to abnormal anatomical condition of brainstem and might contribute to speech delay.

  2. Speech auditory brainstem response (speech ABR) characteristics depending on recording conditions, and hearing status: an experimental parametric study.

    Science.gov (United States)

    Akhoun, Idrick; Moulin, Annie; Jeanvoine, Arnaud; Ménard, Mikael; Buret, François; Vollaire, Christian; Scorretti, Riccardo; Veuillet, Evelyne; Berger-Vachon, Christian; Collet, Lionel; Thai-Van, Hung

    2008-11-15

    Speech elicited auditory brainstem responses (Speech ABR) have been shown to be an objective measurement of speech processing in the brainstem. Given the simultaneous stimulation and recording, and the similarities between the recording and the speech stimulus envelope, there is a great risk of artefactual recordings. This study sought to systematically investigate the source of artefactual contamination in Speech ABR response. In a first part, we measured the sound level thresholds over which artefactual responses were obtained, for different types of transducers and experimental setup parameters. A watermelon model was used to model the human head susceptibility to electromagnetic artefact. It was found that impedances between the electrodes had a great effect on electromagnetic susceptibility and that the most prominent artefact is due to the transducer's electromagnetic leakage. The only artefact-free condition was obtained with insert-earphones shielded in a Faraday cage linked to common ground. In a second part of the study, using the previously defined artefact-free condition, we recorded speech ABR in unilateral deaf subjects and bilateral normal hearing subjects. In an additional control condition, Speech ABR was recorded with the insert-earphones used to deliver the stimulation, unplugged from the ears, so that the subjects did not perceive the stimulus. No responses were obtained from the deaf ear of unilaterally hearing impaired subjects, nor in the insert-out-of-the-ear condition in all the subjects, showing that Speech ABR reflects the functioning of the auditory pathways.

  3. Brainstem response audiometry in the determination of low-frequency hearing loss : a study of various methods for frequency-specific ABR-threshold assessment

    NARCIS (Netherlands)

    E.A.G.J. Conijn

    1992-01-01

    textabstractBrainstem Electric Response Audiometry (BERA) is a method to visualize some of the electric activity generated in the auditory nerve and the brainstem during the processing of sound. The amplitude of the Auditory Brainstem Response (ABR) is very small (0.05-0.5 flV). The potentials

  4. Audiometria de tronco encefálico (abr: o uso do mascaramento na avaliação de indivíduos portadores de perda auditiva unilateral Auditory brainstem response (abr: use of masking in unilateral hearing loss patients

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    Melissa M. T. Toma

    2003-06-01

    Full Text Available A necessidade do mascaramento na avaliação da audição por meio da ABR ainda é um assunto consideravelmente debatido (Durrant & Ferraro, 2001. OBJETIVO: O presente estudo propôs investigar a necessidade do mascaramento contralateral, empregado na orelha normal, ao realizar a ABR em indivíduos portadores de perda auditiva neurossensorial unilateral. FORMA DE ESTUDO: Clínico prospectivo. MATERIAL E MÉTODO: A amostra constituiu-se de 22 indivíduos portadores de perda auditiva neurossensorial unilateral de grau profundo, sendo 10 do sexo feminino e 12 do sexo masculino, com idades variando entre 9 e 44 anos. Todos os indivíduos foram submetidos a: audiometria tonal liminar, logoaudiometria (SRT, IPRF e SDT, medidas de imitância acústica (incluindo a pesquisa dos reflexos acústicos - modo ipsilateral e contralateral e audiometria de tronco encefálico na ausência e na presença do mascaramento. RESULTADOS: Todos os indivíduos apresentaram perda auditiva neurossensorial unilateral de grau profundo e curvas timpanométricas do tipo A bilateralmente. Na avaliação da ABR, 100% da amostra apresentou presença da Onda V na orelha comprometida, sendo que ao introduzir o mascaramento contralateral tais respostas não foram observadas. CONCLUSÕES: O mascaramento é um procedimento necessário para a avaliação da audição por meio da ABR em indivíduos portadores de perdas auditivas unilaterais, visando a obtenção de resultados fidedignos. Na ABR, a atenuação interaural para clicks foi maior (65 dB do que a observada na audiometria tonal liminar, sendo necessário, portanto, uma menor intensidade de mascaramento para eliminar a resposta da via auditiva contralateral.The need of masking in auditory brainstem response (ABR evaluation is still considerably debated issue (Durrant and Ferraro, 2001. AIM: In addition, the present study was to investigate the need of masking in ABR with unilateral hearing loss. STUDY DESIGN: Clinical

  5. Presbycusis and auditory brainstem responses: a review

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    Shilpa Khullar

    2011-06-01

    Full Text Available Age-related hearing loss or presbycusis is a complex phenomenon consisting of elevation of hearing levels as well as changes in the auditory processing. It is commonly classified into four categories depending on the cause. Auditory brainstem responses (ABRs are a type of early evoked potentials recorded within the first 10 ms of stimulation. They represent the synchronized activity of the auditory nerve and the brainstem. Some of the changes that occur in the aging auditory system may significantly influence the interpretation of the ABRs in comparison with the ABRs of the young adults. The waves of ABRs are described in terms of amplitude, latencies and interpeak latency of the different waves. There is a tendency of the amplitude to decrease and the absolute latencies to increase with advancing age but these trends are not always clear due to increase in threshold with advancing age that act a major confounding factor in the interpretation of ABRs.

  6. The role of eABR with intracochlear test electrode in decision making between cochlear and brainstem implants: preliminary results.

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    Cinar, Betul Cicek; Yarali, Mehmet; Atay, Gamze; Bajin, Munir Demir; Sennaroglu, Gonca; Sennaroglu, Levent

    2017-09-01

    The objective of the study was to discuss the findings of intraoperative electrically evoked auditory brainstem response (eABR) test results with a recently designed intracochlear test electrode (ITE) in terms of their relation to decisions of cochlear or auditory brainstem implantation. This clinical study was conducted in Hacettepe University, Department of Otolaryngology, Head and Neck Surgery and Department of Audiology. Subjects were selected from inner ear malformation (IEM) database. Eleven subjects with profound sensorineural hearing loss were included in the current study with age range from 1 year 3 months to 4 years 3 months for children with prelingual hearing loss. There was only one 42-year-old post-lingual subject. eABR was recorded with an ITE and intraoperatively with an original cochlear implant (CI) electrode in 11 cases with different IEMs. Findings of eABR with ITE and their relation to the decision for CI or auditory brainstem implant (ABI) are discussed. Positive eABR test results were found to be dependent on close to normal cochlear structures and auditory nerve. The probability of positive result decreases with increasing degree of malformation severity. The prediction value of eABR via ITE on decision for hearing restoration was found to be questionable in this study. The results of eABR with ITE have predictive value on what we will get with the actual CI electrode. ITE appears to stimulate the cochlea like an actual CI. If the eABR is positive, the results are reliable. However, if eABR is negative, the results should be evaluated with preoperative audiological testing and MRI findings.

  7. Automatic hearing loss detection system based on auditory brainstem response

    International Nuclear Information System (INIS)

    Aldonate, J; Mercuri, C; Reta, J; Biurrun, J; Bonell, C; Gentiletti, G; Escobar, S; Acevedo, R

    2007-01-01

    Hearing loss is one of the pathologies with the highest prevalence in newborns. If it is not detected in time, it can affect the nervous system and cause problems in speech, language and cognitive development. The recommended methods for early detection are based on otoacoustic emissions (OAE) and/or auditory brainstem response (ABR). In this work, the design and implementation of an automated system based on ABR to detect hearing loss in newborns is presented. Preliminary evaluation in adults was satisfactory

  8. Binaural interaction in the auditory brainstem response: a normative study.

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    Van Yper, Lindsey N; Vermeire, Katrien; De Vel, Eddy F J; Battmer, Rolf-Dieter; Dhooge, Ingeborg J M

    2015-04-01

    Binaural interaction can be investigated using auditory evoked potentials. A binaural interaction component can be derived from the auditory brainstem response (ABR-BIC) and is considered evidence for binaural interaction at the level of the brainstem. Although click ABR-BIC has been investigated thoroughly, data on 500 Hz tone-burst (TB) ABR-BICs are scarce. In this study, characteristics of click and 500 Hz TB ABR-BICs are described. Furthermore, reliability of both click and 500 Hz TB ABR-BIC are investigated. Eighteen normal hearing young adults (eight women, ten men) were included. ABRs were recorded in response to clicks and 500 Hz TBs. ABR-BICs were derived by subtracting the binaural response from the sum of the monaural responses measured in opposite ears. Good inter-rater reliability is obtained for both click and 500 Hz TB ABR-BICs. The most reliable peak in click ABR-BIC occurs at a mean latency of 6.06 ms (SD 0.354 ms). Reliable 500 Hz TB ABR-BIC are obtained with a mean latency of 9.47 ms (SD 0.678 ms). Amplitudes are larger for 500 Hz TB ABR-BIC than for clicks. The most reliable peak in click ABR-BIC occurs at the downslope of wave V. Five hundred Hertz TB ABR-BIC is characterized by a broad positivity occurring at the level of wave V. The ABR-BIC is a useful technique to investigate binaural interaction in certain populations. Examples are bilateral hearing aid users, bilateral cochlear implant users and bimodal listeners. The latter refers to the combination of unilateral cochlear implantation and contralateral residual hearing. The majority of these patients have residual hearing in the low frequencies. The current study suggests that 500 Hz TB ABR-BIC may be a suitable technique to assess binaural interaction in this specific population of cochlear implant users. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  9. Speech Evoked Auditory Brainstem Response in Stuttering

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    Ali Akbar Tahaei

    2014-01-01

    Full Text Available Auditory processing deficits have been hypothesized as an underlying mechanism for stuttering. Previous studies have demonstrated abnormal responses in subjects with persistent developmental stuttering (PDS at the higher level of the central auditory system using speech stimuli. Recently, the potential usefulness of speech evoked auditory brainstem responses in central auditory processing disorders has been emphasized. The current study used the speech evoked ABR to investigate the hypothesis that subjects with PDS have specific auditory perceptual dysfunction. Objectives. To determine whether brainstem responses to speech stimuli differ between PDS subjects and normal fluent speakers. Methods. Twenty-five subjects with PDS participated in this study. The speech-ABRs were elicited by the 5-formant synthesized syllable/da/, with duration of 40 ms. Results. There were significant group differences for the onset and offset transient peaks. Subjects with PDS had longer latencies for the onset and offset peaks relative to the control group. Conclusions. Subjects with PDS showed a deficient neural timing in the early stages of the auditory pathway consistent with temporal processing deficits and their abnormal timing may underlie to their disfluency.

  10. The auditory brainstem response in two lizard species

    DEFF Research Database (Denmark)

    Brittan-Powell, Elizabeth F; Christensen-Dalsgaard, Jakob; Tang, Yezhong

    2010-01-01

    Although lizards have highly sensitive ears, it is difficult to condition them to sound, making standard psychophysical assays of hearing sensitivity impractical. This paper describes non-invasive measurements of the auditory brainstem response (ABR) in both Tokay geckos (Gekko gecko; nocturnal...... animals, known for their loud vocalizations) and the green anole (Anolis carolinensis, diurnal, non-vocal animals). Hearing sensitivity was measured in 5 geckos and 7 anoles. The lizards were sedated with isoflurane, and ABRs were measured at levels of 1 and 3% isoflurane. The typical ABR waveform......). Above 5 kHz, however, anoles were more than 20 dB more sensitive than geckos and showed a wider range of sensitivity (1-7 kHz). Generally, thresholds from ABR audiograms were comparable to those of small birds. Best hearing sensitivity, however, extended over a larger frequency range in lizards than...

  11. Effects of Caffeine on Auditory Brainstem Response

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    Saleheh Soleimanian

    2008-06-01

    Full Text Available Background and Aim: Blocking of the adenosine receptor in central nervous system by caffeine can lead to increasing the level of neurotransmitters like glutamate. As the adenosine receptors are present in almost all brain areas like central auditory pathway, it seems caffeine can change conduction in this way. The purpose of this study was to evaluate the effects of caffeine on latency and amplitude of auditory brainstem response(ABR.Materials and Methods: In this clinical trial study 43 normal 18-25 years old male students were participated. The subjects consumed 0, 2 and 3 mg/kg BW caffeine in three different sessions. Auditory brainstem responses were recorded before and 30 minute after caffeine consumption. The results were analyzed by Friedman and Wilcoxone test to assess the effects of caffeine on auditory brainstem response.Results: Compared to control group the latencies of waves III,V and I-V interpeak interval of the cases decreased significantly after 2 and 3mg/kg BW caffeine consumption. Wave I latency significantly decreased after 3mg/kg BW caffeine consumption(p<0.01. Conclusion: Increasing of the glutamate level resulted from the adenosine receptor blocking brings about changes in conduction in the central auditory pathway.

  12. Clinical Experience of Auditory Brainstem Response Testing on Pediatric Patients in the Operating Room

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    Guangwei Zhou

    2012-01-01

    Full Text Available Objectives. To review our experience of conducting auditory brainstem response (ABR test on children in the operating room and discuss the benefits versus limitations of this practice. Methods. Retrospective review study conducted in a pediatric tertiary care facility. A total of 267 patients identified with usable data, including ABR results, medical and surgical notes, and follow-up evaluation. Results. Hearing status successfully determined in all patients based on the ABR results form the operating room. The degrees and the types of hearing loss also documented in most of the cases. In addition, multiple factors that may affect the outcomes of ABR in the operating room identified. Conclusions. Hearing loss in children with complicated medical issues can be accurately evaluated via ABR testing in the operating room. Efforts should be made to eliminate adverse factors to ABR recording, and caution should be taken when interpreting ABR results from the operating room.

  13. Bone-Conduction ABR Tests.

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    Cone-Wesson, Barbara

    1995-01-01

    This article discusses the accuracy of bone-conduction auditory brainstem response (BC-ABR) tests to determine the presence and severity of conductive hearing impairment. It provides warnings about technical pitfalls and recommends incorporating BC-ABR protocols for routine clinical use. It concludes that the method allows estimating cochlear…

  14. Development of Brainstem-Evoked Responses in Congenital Auditory Deprivation

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    J. Tillein

    2012-01-01

    Full Text Available To compare the development of the auditory system in hearing and completely acoustically deprived animals, naive congenitally deaf white cats (CDCs and hearing controls (HCs were investigated at different developmental stages from birth till adulthood. The CDCs had no hearing experience before the acute experiment. In both groups of animals, responses to cochlear implant stimulation were acutely assessed. Electrically evoked auditory brainstem responses (E-ABRs were recorded with monopolar stimulation at different current levels. CDCs demonstrated extensive development of E-ABRs, from first signs of responses at postnatal (p.n. day 3 through appearance of all waves of brainstem response at day 8 p.n. to mature responses around day 90 p.n.. Wave I of E-ABRs could not be distinguished from the artifact in majority of CDCs, whereas in HCs, it was clearly separated from the stimulus artifact. Waves II, III, and IV demonstrated higher thresholds in CDCs, whereas this difference was not found for wave V. Amplitudes of wave III were significantly higher in HCs, whereas wave V amplitudes were significantly higher in CDCs. No differences in latencies were observed between the animal groups. These data demonstrate significant postnatal subcortical development in absence of hearing, and also divergent effects of deafness on early waves II–IV and wave V of the E-ABR.

  15. The auditory brainstem response in two lizard species.

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    Brittan-Powell, Elizabeth F; Christensen-Dalsgaard, Jakob; Tang, Yezhong; Carr, Catherine; Dooling, Robert J

    2010-08-01

    Although lizards have highly sensitive ears, it is difficult to condition them to sound, making standard psychophysical assays of hearing sensitivity impractical. This paper describes non-invasive measurements of the auditory brainstem response (ABR) in both Tokay geckos (Gekko gecko; nocturnal animals, known for their loud vocalizations) and the green anole (Anolis carolinensis, diurnal, non-vocal animals). Hearing sensitivity was measured in 5 geckos and 7 anoles. The lizards were sedated with isoflurane, and ABRs were measured at levels of 1 and 3% isoflurane. The typical ABR waveform in response to click stimulation showed one prominent and several smaller peaks occurring within 10 ms of the stimulus onset. ABRs to brief tone bursts revealed that geckos and anoles were most sensitive between 1.6-2 kHz and had similar hearing sensitivity up to about 5 kHz (thresholds typically 20-50 dB SPL). Above 5 kHz, however, anoles were more than 20 dB more sensitive than geckos and showed a wider range of sensitivity (1-7 kHz). Generally, thresholds from ABR audiograms were comparable to those of small birds. Best hearing sensitivity, however, extended over a larger frequency range in lizards than in most bird species.

  16. Auditory Brainstem Response to Complex Sounds Predicts Self-Reported Speech-in-Noise Performance

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    Anderson, Samira; Parbery-Clark, Alexandra; White-Schwoch, Travis; Kraus, Nina

    2013-01-01

    Purpose: To compare the ability of the auditory brainstem response to complex sounds (cABR) to predict subjective ratings of speech understanding in noise on the Speech, Spatial, and Qualities of Hearing Scale (SSQ; Gatehouse & Noble, 2004) relative to the predictive ability of the Quick Speech-in-Noise test (QuickSIN; Killion, Niquette,…

  17. Low-frequency versus high-frequency synchronisation in chirp-evoked auditory brainstem responses

    DEFF Research Database (Denmark)

    Rønne, Filip Munch; Gøtsche-Rasmussen, Kristian

    2011-01-01

    This study investigates the frequency specific contribution to the auditory brainstem response (ABR) of chirp stimuli. Frequency rising chirps were designed to compensate for the cochlear traveling wave delay, and lead to larger wave-V amplitudes than for click stimuli as more auditory nerve fibr...

  18. Speech-evoked auditory brainstem responses in children with hearing loss.

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    Koravand, Amineh; Al Osman, Rida; Rivest, Véronique; Poulin, Catherine

    2017-08-01

    The main objective of the present study was to investigate subcortical auditory processing in children with sensorineural hearing loss. Auditory Brainstem Responses (ABRs) were recorded using click and speech/da/stimuli. Twenty-five children, aged 6-14 years old, participated in the study: 13 with normal hearing acuity and 12 with sensorineural hearing loss. No significant differences were observed for the click-evoked ABRs between normal hearing and hearing-impaired groups. For the speech-evoked ABRs, no significant differences were found for the latencies of the following responses between the two groups: onset (V and A), transition (C), one of the steady-state wave (F), and offset (O). However, the latency of the steady-state waves (D and E) was significantly longer for the hearing-impaired compared to the normal hearing group. Furthermore, the amplitude of the offset wave O and of the envelope frequency response (EFR) of the speech-evoked ABRs was significantly larger for the hearing-impaired compared to the normal hearing group. Results obtained from the speech-evoked ABRs suggest that children with a mild to moderately-severe sensorineural hearing loss have a specific pattern of subcortical auditory processing. Our results show differences for the speech-evoked ABRs in normal hearing children compared to hearing-impaired children. These results add to the body of the literature on how children with hearing loss process speech at the brainstem level. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. The Physiological Basis and Clinical Use of the Binaural Interaction Component of the Auditory Brainstem Response

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    Klump, Georg M.; Tollin, Daniel J.

    2016-01-01

    The auditory brainstem response (ABR) is a sound-evoked non-invasively measured electrical potential representing the sum of neuronal activity in the auditory brainstem and midbrain. ABR peak amplitudes and latencies are widely used in human and animal auditory research and for clinical screening. The binaural interaction component (BIC) of the ABR stands for the difference between the sum of the monaural ABRs and the ABR obtained with binaural stimulation. The BIC comprises a series of distinct waves, the largest of which (DN1) has been used for evaluating binaural hearing in both normal hearing and hearing-impaired listeners. Based on data from animal and human studies, we discuss the possible anatomical and physiological bases of the BIC (DN1 in particular). The effects of electrode placement and stimulus characteristics on the binaurally evoked ABR are evaluated. We review how inter-aural time and intensity differences affect the BIC and, analyzing these dependencies, draw conclusion about the mechanism underlying the generation of the BIC. Finally, the utility of the BIC for clinical diagnoses are summarized. PMID:27232077

  20. Auditory Brainstem Responses and EMFs Generated by Mobile Phones.

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    Khullar, Shilpa; Sood, Archana; Sood, Sanjay

    2013-12-01

    There has been a manifold increase in the number of mobile phone users throughout the world with the current number of users exceeding 2 billion. However this advancement in technology like many others is accompanied by a progressive increase in the frequency and intensity of electromagnetic waves without consideration of the health consequences. The aim of our study was to advance our understanding of the potential adverse effects of GSM mobile phones on auditory brainstem responses (ABRs). 60 subjects were selected for the study and divided into three groups of 20 each based on their usage of mobile phones. Their ABRs were recorded and analysed for latency of waves I-V as well as interpeak latencies I-III, I-V and III-V (in ms). Results revealed no significant difference in the ABR parameters between group A (control group) and group B (subjects using mobile phones for maximum 30 min/day for 5 years). However the latency of waves was significantly prolonged in group C (subjects using mobile phones for 10 years for a maximum of 30 min/day) as compared to the control group. Based on our findings we concluded that long term exposure to mobile phones may affect conduction in the peripheral portion of the auditory pathway. However more research needs to be done to study the long term effects of mobile phones particularly of newer technologies like smart phones and 3G.

  1. Age and Gender Effects On Auditory Brain Stem Response (ABR

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    Yones Lotfi

    2012-10-01

    Full Text Available Objectives: Auditory Brain Stem Response (ABR is a result of eight nerve and brain stem nuclei stimulation. Several factors may affect the latencies, interpeak latencies and amplitudes in ABR especially sex and age. In this study, age and sex influence on ABR were studied. Methods: This study was performed on 120 cases (60 males and 60 females at Akhavan rehabilitation center of university of welfare and rehabilitation sciences, Tehran, Iran. Cases were divided in three age groups: 18-30, 31-50 and 51-70 years old. Each age group consists of 20 males and 20 females. Age and sex influences on absolute latency of wave I and V, and IPL of I-V were examined. Results: Independent t test showed that females have significantly shorter latency of wave I, V, and IPL I-V latency (P<0.001 than males. Two way ANOVA showed that latency of wave I, V and IPL I-V in 51-70 years old group was significantly higher than 18-30 and 31-50 years old groups (P<0.001 Discussion: According to the results of present study and similar studies, in clinical practice, different norms for older adults and both genders should be established.

  2. Effect of Infant Prematurity on Auditory Brainstem Response at Preschool Age

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    Sara Hasani

    2013-03-01

    Full Text Available Introduction: Preterm birth is a risk factor for a number of conditions that requires comprehensive examination. Our study was designed to investigate the impact of preterm birth on the processing of auditory stimuli and brain structures at the brainstem level at a preschool age.   Materials and Methods: An auditory brainstem response (ABR test was performed with low rates of stimuli in 60 children aged 4 to 6 years. Thirty subjects had been born following a very preterm labor or late-preterm labor and 30 control subjects had been born following a full-term labor.   Results: Significant differences in the ABR test result were observed in terms of the inter-peak intervals of the I–III and III–V waves, and the absolute latency of the III wave (P

  3. Attention-related modulation of auditory brainstem responses during contralateral noise exposure.

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    Ikeda, Kazunari; Sekiguchi, Takahiro; Hayashi, Akiko

    2008-10-29

    As determinants facilitating attention-related modulation of the auditory brainstem response (ABR), two experimental factors were examined: (i) auditory discrimination; and (ii) contralateral masking intensity. Tone pips at 80 dB sound pressure level were presented to the left ear via either single-tone exposures or oddball exposures, whereas white noise was delivered continuously to the right ear at variable intensities (none--80 dB sound pressure level). Participants each conducted two tasks during stimulation, either reading a book (ignoring task) or detecting target tones (attentive task). Task-related modulation within the ABR range was found only during oddball exposures at contralateral masking intensities greater than or equal to 60 dB. Attention-related modulation of ABR can thus be detected reliably during auditory discrimination under contralateral masking of sufficient intensity.

  4. Concentrated pitch discrimination modulates auditory brainstem responses during contralateral noise exposure.

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    Ikeda, Kazunari; Sekiguchi, Takahiro; Hayashi, Akiko

    2010-03-31

    This study examined a notion that auditory discrimination is a requisite for attention-related modulation of the auditory brainstem response (ABR) during contralateral noise exposure. Given that the right ear was exposed continuously with white noise at an intensity of 60-80 dB sound pressure level, tone pips at 80 dB sound pressure level were delivered to the left ear through either single-stimulus or oddball procedures. Participants conducted reading (ignoring task) and counting target tones (attentive task) during stimulation. The oddball but not the single-stimulus procedures elicited task-related modulations in both early (ABR) and late (processing negativity) event-related potentials simultaneously. The elicitation of the attention-related ABR modulation during contralateral noise exposure is thus considered to require auditory discrimination and have the corticofugal nature evidently.

  5. Abnormal auditory forward masking pattern in the brainstem response of individuals with Asperger syndrome

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    Johan Källstrand

    2010-05-01

    Full Text Available Johan Källstrand1, Olle Olsson2, Sara Fristedt Nehlstedt1, Mia Ling Sköld1, Sören Nielzén21SensoDetect AB, Lund, Sweden; 2Department of Clinical Neuroscience, Section of Psychiatry, Lund University, Lund, SwedenAbstract: Abnormal auditory information processing has been reported in individuals with autism spectrum disorders (ASD. In the present study auditory processing was investigated by recording auditory brainstem responses (ABRs elicited by forward masking in adults diagnosed with Asperger syndrome (AS. Sixteen AS subjects were included in the forward masking experiment and compared to three control groups consisting of healthy individuals (n = 16, schizophrenic patients (n = 16 and attention deficit hyperactivity disorder patients (n = 16, respectively, of matching age and gender. The results showed that the AS subjects exhibited abnormally low activity in the early part of their ABRs that distinctly separated them from the three control groups. Specifically, wave III amplitudes were significantly lower in the AS group than for all the control groups in the forward masking condition (P < 0.005, which was not the case in the baseline condition. Thus, electrophysiological measurements of ABRs to complex sound stimuli (eg, forward masking may lead to a better understanding of the underlying neurophysiology of AS. Future studies may further point to specific ABR characteristics in AS individuals that separate them from individuals diagnosed with other neurodevelopmental diseases.Keywords: asperger syndrome, auditory brainstem response, forward masking, psychoacoustics

  6. Auditory brainstem response in neonates: influence of gender and weight/gestational age ratio

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    Rosanna M. Giaffredo Angrisani

    2013-12-01

    Full Text Available OBJECTIVE: To investigate the influence of gender and weight/gestational age ratio on the Auditory Brainstem Response (ABR in preterm (PT and term (T newborns. METHODS: 176 newborns were evaluated by ABR; 88 were preterm infants - 44 females (22 small and 22 appropriate for gestational age and 44 males (22 small and 22 appropriate for gestational age. The preterm infants were compared to 88 term infants - 44 females (22 small and 22 appropriate for gestational age and 44 males (22 small and 22 appropriate for gestational age. All newborns had bilateral presence of transient otoacoustic emissions and type A tympanometry. RESULTS: No interaural differences were found. ABR response did not differentiate newborns regarding weight/gestational age in males and females. Term newborn females showed statistically shorter absolute latencies (except on wave I than males. This finding did not occur in preterm infants, who had longer latencies than term newborns, regardless of gender. CONCLUSIONS: Gender and gestational age influence term infants' ABR, with lower responses in females. The weight/gestational age ratio did not influence ABR response in either groups.

  7. Auditory brainstem evoked responses and temperature monitoring during pediatric cardiopulmonary bypass.

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    Rodriguez, R A; Edmonds, H L; Auden, S M; Austin, E H

    1999-09-01

    To examine the effects of temperature on auditory brainstem responses (ABRs) in infants during hypothermic cardiopulmonary bypass for total circulatory arrest (TCA). The relationship between ABRs (as a surrogate measure of core-brain temperature) and body temperature as measured at several temperature monitoring sites was determined. In a prospective, observational study, ABRs were recorded non-invasively at normothermia and at every 1 or 2 degrees C change in ear-canal temperature during cooling and rewarming in 15 infants (ages: 2 days to 14 months) that required TCA. The ABR latencies and amplitudes and the lowest temperatures at which an ABR was identified (the threshold) were measured during both cooling and rewarming. Temperatures from four standard temperature monitoring sites were simultaneously recorded. The latencies of ABRs increased and amplitudes decreased with cooling (P < 0.01), but rewarming reversed these effects. The ABR threshold temperature as related to each monitoring site (ear-canal, nasopharynx, esophagus and bladder) was respectively determined as 23 +/- 2.2 degrees C, 20.8 +/- 1.7 degrees C, 14.6 +/- 3.4 degrees C, and 21.5 +/- 3.8 degrees C during cooling and 21.8 +/- 1.6 degrees C, 22.4 +/- 2.0 degrees C, 27.6 +/- 3.6 degrees C, and 23.0 +/- 2.4 degrees C during rewarming. The rewarming latencies were shorter and Q10 latencies smaller than the corresponding cooling values (P < 0.01). Esophageal and bladder sites were more susceptible to temperature variations as compared with the ear-canal and nasopharynx. No temperature site reliably predicted an electrophysiological threshold. A faster latency recovery during rewarming suggests that body temperature monitoring underestimates the effects of rewarming in the core-brain. ABRs may be helpful to monitor the effects of cooling and rewarming on the core-brain during pediatric cardiopulmonary bypass.

  8. Test-retest reliability of speech-evoked auditory brainstem response in healthy children at a low sensation level.

    Science.gov (United States)

    Zakaria, Mohd Normani; Jalaei, Bahram

    2017-11-01

    Auditory brainstem responses evoked by complex stimuli such as speech syllables have been studied in normal subjects and subjects with compromised auditory functions. The stability of speech-evoked auditory brainstem response (speech-ABR) when tested over time has been reported but the literature is limited. The present study was carried out to determine the test-retest reliability of speech-ABR in healthy children at a low sensation level. Seventeen healthy children (6 boys, 11 girls) aged from 5 to 9 years (mean = 6.8 ± 3.3 years) were tested in two sessions separated by a 3-month period. The stimulus used was a 40-ms syllable /da/ presented at 30 dB sensation level. As revealed by pair t-test and intra-class correlation (ICC) analyses, peak latencies, peak amplitudes and composite onset measures of speech-ABR were found to be highly replicable. Compared to other parameters, higher ICC values were noted for peak latencies of speech-ABR. The present study was the first to report the test-retest reliability of speech-ABR recorded at low stimulation levels in healthy children. Due to its good stability, it can be used as an objective indicator for assessing the effectiveness of auditory rehabilitation in hearing-impaired children in future studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Auditory brainstem response screening for hearing loss in high risk neonates.

    Science.gov (United States)

    Watson, D R; McClelland, R J; Adams, D A

    1996-07-01

    The present paper reports the findings of a 7 year study evaluating the use of the auditory brainstem response (ABR) as the basis of a hearing screening procedure in a group of newborns at increased risk of hearing impairment. A Special Care Baby Unit (SCBU) population of 417 infants with diverse clinical backgrounds and treatment histories was tested for hearing impairment at birth using ABR audiometry. Some 332 passed the original screen at 30 dBnHL test level in both ears. Of the failure group, 18 did not survive and 32 had some degree of hearing impairment confirmed, nine of which were sensorineural in origin. An increased incidence of persistent middle ear disease was also noted in the failure group. A detailed operational analysis demonstrates that provided appropriate pass/fail criteria are adopted, the ABR technique offers excellent sensitivity and specificity for the detection of significant hearing loss in the test population. Furthermore, the study establishes that implementation of an ABR-based screening programme could reduce the average age at detection of permanent hearing loss by 7 months. A cost assessment shows that the introduction of such a targetted screening procedure could be done at a reasonable outlay.

  10. Development of a Chirp Stimulus PC-Based Auditory Brainstem Response Audiometer

    Directory of Open Access Journals (Sweden)

    Ali AL-Afsaa

    2004-05-01

    Full Text Available Hearing losses during infancy and childhood have many negative future effects and impacts on the child life and productivity. The earlier detection of hearing losses, the earlier medical intervention and then the greater benefit of remediation will be. During this research a PC-based audiometer is designed and, currently, the audiometer prototype is in its final development steps. It is based on the auditory brainstem response (ABR method. Chirp stimuli instead of traditional click stimuli will be used to invoke the ABR signal. The stimulus is designed to synchronize the hair cells movement when it spreads out over the cochlea. In addition to the available hardware utilization (PC and PCI board, the efforts confined to design and implement a hardware prototype and to develop a software package that enables the system to behave as ABR audiometer. By using such a method and chirp stimulus, it is expected to be able to detect hearing impairment (sensorineural in the first few days of the life and conduct hearing test at low frequency of stimulus. Currently, the intended chirp stimulus has been successfully generated and the implemented module is able to amplify a signal (on the order of ABR signal to a recordable level. Moreover, a NI-DAQ data acquisition board has been chosen to implement the PC-prototype interface.

  11. A comparison of auditory brainstem responses across diving bird species

    Science.gov (United States)

    Crowell, Sara E.; Berlin, Alicia; Carr, Catherine E.; Olsen, Glenn H.; Therrien, Ronald E.; Yannuzzi, Sally E.; Ketten, Darlene R.

    2015-01-01

    There is little biological data available for diving birds because many live in hard-to-study, remote habitats. Only one species of diving bird, the black-footed penguin (Spheniscus demersus), has been studied in respect to auditory capabilities (Wever et al., Proc Natl Acad Sci USA 63:676–680, 1969). We, therefore, measured in-air auditory threshold in ten species of diving birds, using the auditory brainstem response (ABR). The average audiogram obtained for each species followed the U-shape typical of birds and many other animals. All species tested shared a common region of the greatest sensitivity, from 1000 to 3000 Hz, although audiograms differed significantly across species. Thresholds of all duck species tested were more similar to each other than to the two non-duck species tested. The red-throated loon (Gavia stellata) and northern gannet (Morus bassanus) exhibited the highest thresholds while the lowest thresholds belonged to the duck species, specifically the lesser scaup (Aythya affinis) and ruddy duck (Oxyura jamaicensis). Vocalization parameters were also measured for each species, and showed that with the exception of the common eider (Somateria mollisima), the peak frequency, i.e., frequency at the greatest intensity, of all species' vocalizations measured here fell between 1000 and 3000 Hz, matching the bandwidth of the most sensitive hearing range.

  12. Brainstem auditory responses to resolved and unresolved harmonics of a synthetic vowel in quiet and noise.

    Science.gov (United States)

    Laroche, Marilyn; Dajani, Hilmi R; Prévost, François; Marcoux, André M

    2013-01-01

    This study investigated speech auditory brainstem responses (speech ABR) with variants of a synthetic vowel in quiet and in background noise. Its objectives were to study the noise robustness of the brainstem response at the fundamental frequency F0 and at the first formant F1, evaluate how the resolved/unresolved harmonics regions in speech contribute to the response at F0, and investigate the origin of the response at F0 to resolved and unresolved harmonics in speech. In total, 18 normal-hearing subjects (11 women, aged 18-33 years) participated in this study. Speech ABRs were recorded using variants of a 300 msec formant-synthesized /a/ vowel in quiet and in white noise. The first experiment employed three variants containing the first three formants F1 to F3, F1 only, and F2 and F3 only with relative formant levels following those reported in the literature. The second experiment employed three variants containing F1 only, F2 only, and F3 only, with the formants equalized to the same level and the signal-to-noise ratio (SNR) maintained at -5 dB. Overall response latency was estimated, and the amplitude and local SNR of the envelope following response at F0 and of the frequency following response at F1 were compared for the different stimulus variants in quiet and in noise. The response at F0 was more robust to noise than that at F1. There were no statistically significant differences in the response at F0 caused by the three stimulus variants in both experiments in quiet. However, the response at F0 with the variant dominated by resolved harmonics was more robust to noise than the response at F0 with the stimulus variants dominated by unresolved harmonics. The latencies of the responses in all cases were very similar in quiet, but the responses at F0 due to resolved and unresolved harmonics combined nonlinearly when both were present in the stimulus. Speech ABR has been suggested as a marker of central auditory processing. The results of this study support

  13. Investigation of Auditory Brain Stem Responses (ABRs In Children with Down Syndrome

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    Mohsen Monadi

    2013-04-01

    Full Text Available Objective: The aim of this study was comparing ABR in normal and down children. Materials & Methods: This study was performed between 1388 to 1391 at Akhavan rehabilitation center of University of Social Welfare and Rehabilitation Sciences Tehran and Babol Amir Kola hospital. Forty five 3-6 year-old boy with Down’s syndrome and forty five normal children were selected from available population. After case history, otoscopy and basic hearing tests, ABR test was performed. In ABR absolute latencies, interpeak latencies and amplitude ratio of V/I were analyzed. For analyzing data, parametric independent t test was selected. Results: Latencies and inter-peak latencies of I-III, I-V (P-value<0.001, III-V (P-value=0.01 and V/I amplitude ratio (P-value<0.001 were shorter than normal. Children with Down syndrome had significantly higher threshold than normal children (P-value<0.001. Conclusion: Peripheral auditory system development is delayed and brainstem function in children with Down’s syndrome is abnormal. Early diagnosis of hearing impairments and intervention in these children is very important because it affects communication skills.

  14. Comparison of Auditory Brainstem Response in Noise Induced Tinnitus and Non-Tinnitus Control Subjects

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    Ghassem Mohammadkhani

    2009-12-01

    Full Text Available Background and Aim: Tinnitus is an unpleasant sound which can cause some behavioral disorders. According to evidence the origin of tinnitus is not only in peripheral but also in central auditory system. So evaluation of central auditory system function is necessary. In this study Auditory brainstem responses (ABR were compared in noise induced tinnitus and non-tinnitus control subjects.Materials and Methods: This cross-sectional, descriptive and analytic study is conducted in 60 cases in two groups including of 30 noise induced tinnitus and 30 non-tinnitus control subjects. ABRs were recorded ipsilateraly and contralateraly and their latencies and amplitudes were analyzed.Results: Mean interpeak latencies of III-V (p= 0.022, I-V (p=0.033 in ipsilatral electrode array and mean absolute latencies of IV (p=0.015 and V (p=0.048 in contralatral electrode array were significantly increased in noise induced tinnitus group relative to control group. Conclusion: It can be concluded from that there are some decrease in neural transmission time in brainstem and there are some sign of involvement of medial nuclei in olivery complex in addition to lateral lemniscus.

  15. Rapid measurement of auditory filter shape in mice using the auditory brainstem response and notched noise.

    Science.gov (United States)

    Lina, Ioan A; Lauer, Amanda M

    2013-04-01

    The notched noise method is an effective procedure for measuring frequency resolution and auditory filter shapes in both human and animal models of hearing. Briefly, auditory filter shape and bandwidth estimates are derived from masked thresholds for tones presented in noise containing widening spectral notches. As the spectral notch widens, increasingly less of the noise falls within the auditory filter and the tone becomes more detectible until the notch width exceeds the filter bandwidth. Behavioral procedures have been used for the derivation of notched noise auditory filter shapes in mice; however, the time and effort needed to train and test animals on these tasks renders a constraint on the widespread application of this testing method. As an alternative procedure, we combined relatively non-invasive auditory brainstem response (ABR) measurements and the notched noise method to estimate auditory filters in normal-hearing mice at center frequencies of 8, 11.2, and 16 kHz. A complete set of simultaneous masked thresholds for a particular tone frequency were obtained in about an hour. ABR-derived filter bandwidths broadened with increasing frequency, consistent with previous studies. The ABR notched noise procedure provides a fast alternative to estimating frequency selectivity in mice that is well-suited to high through-put or time-sensitive screening. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Long-term evolution of brainstem electrical evoked responses to sound after restricted ablation of the auditory cortex.

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    Verónica Lamas

    Full Text Available INTRODUCTION: This study aimed to assess the top-down control of sound processing in the auditory brainstem of rats. Short latency evoked responses were analyzed after unilateral or bilateral ablation of auditory cortex. This experimental paradigm was also used towards analyzing the long-term evolution of post-lesion plasticity in the auditory system and its ability to self-repair. METHOD: Auditory cortex lesions were performed in rats by stereotactically guided fine-needle aspiration of the cerebrocortical surface. Auditory Brainstem Responses (ABR were recorded at post-surgery day (PSD 1, 7, 15 and 30. Recordings were performed under closed-field conditions, using click trains at different sound intensity levels, followed by statistical analysis of threshold values and ABR amplitude and latency variables. Subsequently, brains were sectioned and immunostained for GAD and parvalbumin to assess the location and extent of lesions accurately. RESULTS: Alterations in ABR variables depended on the type of lesion and post-surgery time of ABR recordings. Accordingly, bilateral ablations caused a statistically significant increase in thresholds at PSD1 and 7 and a decrease in waves amplitudes at PSD1 that recover at PSD7. No effects on latency were noted at PSD1 and 7, whilst recordings at PSD15 and 30 showed statistically significant decreases in latency. Conversely, unilateral ablations had no effect on auditory thresholds or latencies, while wave amplitudes only decreased at PSD1 strictly in the ipsilateral ear. CONCLUSION: Post-lesion plasticity in the auditory system acts in two time periods: short-term period of decreased sound sensitivity (until PSD7, most likely resulting from axonal degeneration; and a long-term period (up to PSD7, with changes in latency responses and recovery of thresholds and amplitudes values. The cerebral cortex may have a net positive gain on the auditory pathway response to sound.

  17. Brainstem evoked potentials in infantile spasms

    International Nuclear Information System (INIS)

    Miyazaki, Masahito; Hashimoto, Toshiaki; Murakawa, Kazuyoshi; Tayama, Masanobu; Kuroda, Yasuhiro

    1992-01-01

    In ten patients with infantile spasms, brainstem evoked potentials and MRI examinations were performed to evaluate the brainstem involvement. The result of short latency somatosensory evoked potentials (SSEP) following the right median nerve stimulation revealed abnormal findings including the absence or low amplitudes of the waves below wave P3 and delayed central conduction time in 7 of the ten patients. The result of auditory brainstem responses (ABR) revealed abnormal findings including low amplitudes of wave V, prolonged interpeak latency of waves I-V and absence of the waves below wave IV in 5 of the ten patients. The result of the MRI examinations revealed various degrees of the brainstem atrophy in 6 of the ten patients, all of whom showed abnormal brainstem evoked potentials. The result of this study demonstrates that patients with infantile spasms are frequently associated with brainstem dysfunction and raises the possibility that brainstem atrophy might be a cause of infantile spasms. (author)

  18. Auditory brainstem response latency in forward masking, a marker of sensory deficits in listeners with normal hearing thresholds

    DEFF Research Database (Denmark)

    Mehraei, Golbarg; Paredes Gallardo, Andreu; Shinn-Cunningham, Barbara G.

    2017-01-01

    In rodent models, acoustic exposure too modest to elevate hearing thresholds can nonetheless cause auditory nerve fiber deafferentation, interfering with the coding of supra-threshold sound. Low-spontaneous rate nerve fibers, important for encoding acoustic information at supra-threshold levels...... and in noise, are more susceptible to degeneration than high-spontaneous rate fibers. The change in auditory brainstem response (ABR) wave-V latency with noise level has been shown to be associated with auditory nerve deafferentation. Here, we measured ABR in a forward masking paradigm and evaluated wave......-V latency changes with increasing masker-to-probe intervals. In the same listeners, behavioral forward masking detection thresholds were measured. We hypothesized that 1) auditory nerve fiber deafferentation increases forward masking thresholds and increases wave-V latency and 2) a preferential loss of low...

  19. Effects of noise exposure on neonatal auditory brainstem response thresholds in pregnant guinea pigs at different gestational periods.

    Science.gov (United States)

    Morimoto, Chihiro; Nario, Kazuhiko; Nishimura, Tadashi; Shimokura, Ryota; Hosoi, Hiroshi; Kitahara, Tadashi

    2017-01-01

    Noise exposure during pregnancy has been reported to cause fetal hearing impairment. However, little is known about the effects of noise exposure during various gestational stages on postnatal hearing. In the present study, we investigated the effects of noise exposure on auditory brainstem response (ABR) at the early, mid-, and late gestational periods in newborn guinea pigs. Pregnant guinea pigs were exposed to 4-kHz pure tone at a 120-dB sound pressure level for 4 h. We divided the animals into four groups as follows: the control, early gestational exposure, mid-gestational exposure, and late gestational exposure groups. ABR thresholds and latencies in newborns were recorded using 1-, 2-, and 4-kHz tone burst on postnatal days 1, 7, 14, and 28. Changes in ABR thresholds and latencies were measured between the 4 × 4 and 4 × 3 factorial groups mentioned above (gestational periods × postnatal days, gestational periods × frequencies). The thresholds were low in the order of control group guinea pigs. This is the first study to show that noise exposure during the early, mid-, and late gestational periods significantly elevated ABR thresholds in neonatal guinea pigs. © 2016 Japan Society of Obstetrics and Gynecology.

  20. Age-Related Changes in Binaural Interaction at Brainstem Level.

    Science.gov (United States)

    Van Yper, Lindsey N; Vermeire, Katrien; De Vel, Eddy F J; Beynon, Andy J; Dhooge, Ingeborg J M

    2016-01-01

    Age-related hearing loss hampers the ability to understand speech in adverse listening conditions. This is attributed to a complex interaction of changes in the peripheral and central auditory system. One aspect that may deteriorate across the lifespan is binaural interaction. The present study investigates binaural interaction at the level of the auditory brainstem. It is hypothesized that brainstem binaural interaction deteriorates with advancing age. Forty-two subjects of various age participated in the study. Auditory brainstem responses (ABRs) were recorded using clicks and 500 Hz tone-bursts. ABRs were elicited by monaural right, monaural left, and binaural stimulation. Binaural interaction was investigated in two ways. First, grand averages of the binaural interaction component were computed for each age group. Second, wave V characteristics of the binaural ABR were compared with those of the summed left and right ABRs. Binaural interaction in the click ABR was demonstrated by shorter latencies and smaller amplitudes in the binaural compared with the summed monaural responses. For 500 Hz tone-burst ABR, no latency differences were found. However, amplitudes were significantly smaller in the binaural than summed monaural condition. An age-effect was found for 500 Hz tone-burst, but not for click ABR. Brainstem binaural interaction seems to decline with age. Interestingly, these changes seem to be stimulus-dependent.

  1. Aging effects on the binaural interaction component of the auditory brainstem response in the Mongolian gerbil: Effects of interaural time and level differences.

    Science.gov (United States)

    Laumen, Geneviève; Tollin, Daniel J; Beutelmann, Rainer; Klump, Georg M

    2016-07-01

    The effect of interaural time difference (ITD) and interaural level difference (ILD) on wave 4 of the binaural and summed monaural auditory brainstem responses (ABRs) as well as on the DN1 component of the binaural interaction component (BIC) of the ABR in young and old Mongolian gerbils (Meriones unguiculatus) was investigated. Measurements were made at a fixed sound pressure level (SPL) and a fixed level above visually detected ABR threshold to compensate for individual hearing threshold differences. In both stimulation modes (fixed SPL and fixed level above visually detected ABR threshold) an effect of ITD on the latency and the amplitude of wave 4 as well as of the BIC was observed. With increasing absolute ITD values BIC latencies were increased and amplitudes were decreased. ILD had a much smaller effect on these measures. Old animals showed a reduced amplitude of the DN1 component. This difference was due to a smaller wave 4 in the summed monaural ABRs of old animals compared to young animals whereas wave 4 in the binaural-evoked ABR showed no age-related difference. In old animals the small amplitude of the DN1 component was correlated with small binaural-evoked wave 1 and wave 3 amplitudes. This suggests that the reduced peripheral input affects central binaural processing which is reflected in the BIC. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. ACGT-containing abscisic acid response element (ABRE) and coupling element 3 (CE3) are functionally equivalent.

    Science.gov (United States)

    Hobo, T; Asada, M; Kowyama, Y; Hattori, T

    1999-09-01

    ACGT-containing ABA response elements (ABREs) have been functionally identified in the promoters of various genes. In addition, single copies of ABRE have been found to require a cis-acting, coupling element to achieve ABA induction. A coupling element 3 (CE3) sequence, originally identified as such in the barley HVA1 promoter, is found approximately 30 bp downstream of motif A (ACGT-containing ABRE) in the promoter of the Osem gene. The relationship between these two elements was further defined by linker-scan analyses of a 55 bp fragment of the Osem promoter, which is sufficient for ABA-responsiveness and VP1 activation. The analyses revealed that both motif A and CE3 sequence were required not only for ABA-responsiveness but also for VP1 activation. Since the sequences of motif A and CE3 were found to be similar, motif-exchange experiments were carried out. The experiments demonstrated that motif A and CE3 were interchangeable by each other with respect to both ABA and VP1 regulation. In addition, both sequences were shown to be recognized by a VP1-interacting, ABA-responsive bZIP factor TRAB1. These results indicate that ACGT-containing ABREs and CE3 are functionally equivalent cis-acting elements. Furthermore, TRAB1 was shown to bind two other non-ACGT ABREs. Based on these results, all these ABREs including CE3 are proposed to be categorized into a single class of cis-acting elements.

  3. The pattern of auditory brainstem response wave V maturation in cochlear-implanted children.

    Science.gov (United States)

    Thai-Van, Hung; Cozma, Sebastian; Boutitie, Florent; Disant, François; Truy, Eric; Collet, Lionel

    2007-03-01

    Maturation of acoustically evoked brainstem responses (ABR) in hearing children is not complete at birth but rather continues over the first two years of life. In particular, it has been established that the decrease in ABR wave V latency can be modeled as the sum of two decaying exponential functions with respective time-constants of 4 and 50 weeks [Eggermont, J.J., Salamy, A., 1988a. Maturational time-course for the ABR in preterm and full term infants. Hear Res 33, 35-47; Eggermont, J.J., Salamy, A., 1988b. Development of ABR parameters in a preterm and a term born population. Ear Hear 9, 283-9]. Here, we investigated the maturation of electrically evoked auditory brainstem responses (EABR) in 55 deaf children who recovered hearing after cochlear implantation, and proposed a predictive model of EABR maturation depending on the onset of deafness. The pattern of EABR maturation over the first 2 years of cochlear implant use was compared with the normal pattern of ABR maturation in hearing children. Changes in EABR wave V latency over the 2 years following cochlear implant connection were analyzed in two groups of children. The first group (n=41) consisted of children with early-onset of deafness (mostly congenital), and the second (n=14) of children who had become profoundly deaf after 1 year of age. The modeling of changes in EABR wave V latency with time was based on the mean values from each of the two groups, allowing comparison of the rates of EABR maturation between groups. Differences between EABRs elicited at the basal and apical ends of the implant electrode array were also tested. There was no influence of age at implantation on the rate of wave V latency change. The main factor for EABR changes was the time in sound. Indeed, significant maturation was observed over the first 2 years of implant use only in the group with early-onset deafness. In this group maturation of wave V progressed as in the ABR model of [Eggermont, J.J., Salamy, A., 1988a

  4. The brain stem function in patients with brain bladder; Clinical evaluation using dynamic CT scan and auditory brainstem response

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Toshihiro (Yokohama City Univ. (Japan). Faculty of Medicine)

    1990-11-01

    A syndrome of detrusor-sphincter dyssynergia (DSD) is occasionally found in patients with brain bladder. To evaluate the brain stem function in cases of brain bladder, urodynamic study, dynamic CT scan of the brain stem (DCT) and auditory brainstem response (ABR) were performed. The region of interest of DCT aimed at the posterolateral portion of the pons. The results were analysed in contrast with the presense of DSD in urodynamic study. DCT studies were performed in 13 cases with various brain diseases and 5 control cases without neurological diseases. Abnormal patterns of the time-density curve consisted of low peak value, prolongation of filling time and low rapid washout ratio (low clearance ratio) of the contrast medium. Four of 6 cases with DSD showed at least one of the abnormal patterns of the time-density curve bilaterally. In 7 cases without DSD none showed bilateral abnormality of the curve and in 2 of 7 cases only unilateral abnormality was found. ABR was performed in 8 patients with brain diseases. The interpeak latency of the wave I-V (I-V IPL) was considered to be prolonged in 2 cases with DSD compared to that of 4 without DSD. In 2 cases with DSD who had normal DCT findings, measurement of the I-V IPL was impossible due to abnormal pattern of the ABR wave. Above mentioned results suggests the presence of functional disturbance at the posterolateral portion of the pons in cases of brain bladder with DSD. (author).

  5. Prenatal exposure to multiple pesticides is associated with auditory brainstem response at 9months in a cohort study of Chinese infants.

    Science.gov (United States)

    Sturza, Julie; Silver, Monica K; Xu, Lin; Li, Mingyan; Mai, Xiaoqin; Xia, Yankai; Shao, Jie; Lozoff, Betsy; Meeker, John

    2016-01-01

    Pesticides are associated with poorer neurodevelopmental outcomes, but little is known about the effects on sensory functioning. Auditory brainstem response (ABR) and pesticide data were available for 27 healthy, full-term 9-month-old infants participating in a larger study of early iron deficiency and neurodevelopment. Cord blood was analyzed by gas chromatography-mass spectrometry for levels of 20 common pesticides. The ABR forward-masking condition consisted of a click stimulus (masker) delivered via ear canal transducers followed by an identical stimulus delayed by 8, 16, or 64 milliseconds (ms). ABR peak latencies were evaluated as a function of masker-stimulus time interval. Shorter wave latencies reflect faster neural conduction, more mature auditory pathways, and greater degree of myelination. Linear regression models were used to evaluate associations between total number of pesticides detected and ABR outcomes. We considered an additive or synergistic effect of poor iron status by stratifying our analysis by newborn ferritin (based on median split). Infants in the sample were highly exposed to pesticides; a mean of 4.1 pesticides were detected (range 0-9). ABR Wave V latency and central conduction time (CCT) were associated with the number of pesticides detected in cord blood for the 64ms and non-masker conditions. A similar pattern seen for CCT from the 8ms and 16ms conditions, although statistical significance was not reached. Increased pesticide exposure was associated with longer latency. The relation between number of pesticides detected in cord blood and CCT depended on the infant's cord blood ferritin level. Specifically, the relation was present in the lower cord blood ferritin group but not the higher cord blood ferritin group. ABR processing was slower in infants with greater prenatal pesticide exposure, indicating impaired neuromaturation. Infants with lower cord blood ferritin appeared to be more sensitive to the effects of prenatal pesticide

  6. Genome-wide analysis of ABA-responsive elements ABRE and CE3 reveals divergent patterns in Arabidopsis and rice

    Directory of Open Access Journals (Sweden)

    Riaño-Pachón Diego

    2007-08-01

    Full Text Available Abstract Background In plants, complex regulatory mechanisms are at the core of physiological and developmental processes. The phytohormone abscisic acid (ABA is involved in the regulation of various such processes, including stomatal closure, seed and bud dormancy, and physiological responses to cold, drought and salinity stress. The underlying tissue or plant-wide control circuits often include combinatorial gene regulatory mechanisms and networks that we are only beginning to unravel with the help of new molecular tools. The increasing availability of genomic sequences and gene expression data enables us to dissect ABA regulatory mechanisms at the individual gene expression level. In this paper we used an in-silico-based approach directed towards genome-wide prediction and identification of specific features of ABA-responsive elements. In particular we analysed the genome-wide occurrence and positional arrangements of two well-described ABA-responsive cis-regulatory elements (CREs, ABRE and CE3, in thale cress (Arabidopsis thaliana and rice (Oryza sativa. Results Our results show that Arabidopsis and rice use the ABA-responsive elements ABRE and CE3 distinctively. Earlier reports for various monocots have identified CE3 as a coupling element (CE associated with ABRE. Surprisingly, we found that while ABRE is equally abundant in both species, CE3 is practically absent in Arabidopsis. ABRE-ABRE pairs are common in both genomes, suggesting that these can form functional ABA-responsive complexes (ABRCs in Arabidopsis and rice. Furthermore, we detected distinct combinations, orientation patterns and DNA strand preferences of ABRE and CE3 motifs in rice gene promoters. Conclusion Our computational analyses revealed distinct recruitment patterns of ABA-responsive CREs in upstream sequences of Arabidopsis and rice. The apparent absence of CE3s in Arabidopsis suggests that another CE pairs with ABRE to establish a functional ABRC capable of

  7. Genome-wide analysis of ABA-responsive elements ABRE and CE3 reveals divergent patterns in Arabidopsis and rice.

    Science.gov (United States)

    Gómez-Porras, Judith L; Riaño-Pachón, Diego Mauricio; Dreyer, Ingo; Mayer, Jorge E; Mueller-Roeber, Bernd

    2007-08-01

    In plants, complex regulatory mechanisms are at the core of physiological and developmental processes. The phytohormone abscisic acid (ABA) is involved in the regulation of various such processes, including stomatal closure, seed and bud dormancy, and physiological responses to cold, drought and salinity stress. The underlying tissue or plant-wide control circuits often include combinatorial gene regulatory mechanisms and networks that we are only beginning to unravel with the help of new molecular tools. The increasing availability of genomic sequences and gene expression data enables us to dissect ABA regulatory mechanisms at the individual gene expression level. In this paper we used an in-silico-based approach directed towards genome-wide prediction and identification of specific features of ABA-responsive elements. In particular we analysed the genome-wide occurrence and positional arrangements of two well-described ABA-responsive cis-regulatory elements (CREs), ABRE and CE3, in thale cress (Arabidopsis thaliana) and rice (Oryza sativa). Our results show that Arabidopsis and rice use the ABA-responsive elements ABRE and CE3 distinctively. Earlier reports for various monocots have identified CE3 as a coupling element (CE) associated with ABRE. Surprisingly, we found that while ABRE is equally abundant in both species, CE3 is practically absent in Arabidopsis. ABRE-ABRE pairs are common in both genomes, suggesting that these can form functional ABA-responsive complexes (ABRCs) in Arabidopsis and rice. Furthermore, we detected distinct combinations, orientation patterns and DNA strand preferences of ABRE and CE3 motifs in rice gene promoters. Our computational analyses revealed distinct recruitment patterns of ABA-responsive CREs in upstream sequences of Arabidopsis and rice. The apparent absence of CE3s in Arabidopsis suggests that another CE pairs with ABRE to establish a functional ABRC capable of interacting with transcription factors. Further studies will be

  8. Preservation of auditory brainstem response thresholds after cochleostomy and titanium microactuator implantation in the lateral wall of cat scala tympani.

    Science.gov (United States)

    Lesinski, S George; Prewitt, Jessica; Bray, Victor; Aravamudhan, Radhika; Bermeo Blanco, Oscar A; Farmer-Fedor, Brenda L; Ward, Jonette A

    2014-04-01

    The safety of implanting a titanium microactuator into the lateral wall of cat scala tympani was assessed by comparing preoperative and postoperative auditory brainstem response (ABR) thresholds for 1 to 3 months. The safety of directly stimulating cochlear perilymph with an implantable hearing system requires maintaining preoperative hearing levels. This cat study is an essential step in the development of the next generation of fully implantable hearing devices for humans. Following GLP surgical standards, a 1-mm cochleostomy was drilled into the lateral wall of the scala tympani, and a nonfunctioning titanium anchor/microactuator assembly was inserted in 8 cats. The scala media was damaged in the 1 cat. ABR thresholds with click and 4- and 8-kHz stimuli were measured preoperatively and compared with postoperative thresholds at 1, 2, and 3 months. Nonimplanted ear thresholds were also measured to establish statistical significance for threshold shifts (>28.4 dB). Two audiologists independently interpreted thresholds. Postoperatively, 7 cats implanted in the scala tympani demonstrated no significant ABR threshold shift for click stimulus; one shifted ABR thresholds to 4- and 8-kHz stimuli. The eighth cat, with surgical damage to the scala media, maintained stable click threshold but had a significant shift to 4- and 8-kHz stimuli. This cat study provides no evidence of worsening hearing thresholds after fenestration of the scala tympani and insertion of a titanium anchor/microactuator, provided there is no surgical trauma to the scala media and the implanted device is securely anchored in the cochleostomy. These 2 issues have been resolved in the development of a fully implantable hearing system for humans. The long-term hearing stability (combined with histologic studies) reaffirm that the microactuator is well tolerated by the cat cochlea.

  9. Relations between perceptual measures of temporal processing, auditory-evoked brainstem responses and speech intelligibility in noise

    DEFF Research Database (Denmark)

    Papakonstantinou, Alexandra; Strelcyk, Olaf; Dau, Torsten

    2011-01-01

    This study investigates behavioural and objective measures of temporal auditory processing and their relation to the ability to understand speech in noise. The experiments were carried out on a homogeneous group of seven hearing-impaired listeners with normal sensitivity at low frequencies (up to 1...... kHz) and steeply sloping hearing losses above 1 kHz. For comparison, data were also collected for five normalhearing listeners. Temporal processing was addressed at low frequencies by means of psychoacoustical frequency discrimination, binaural masked detection and amplitude modulation (AM......) detection. In addition, auditory brainstem responses (ABRs) to clicks and broadband rising chirps were recorded. Furthermore, speech reception thresholds (SRTs) were determined for Danish sentences in speechshaped noise. The main findings were: (1) SRTs were neither correlated with hearing sensitivity...

  10. Auditory brainstem responses of CBA/J mice with neonatal conductive hearing losses and treatment with GM1 ganglioside.

    Science.gov (United States)

    Money, M K; Pippin, G W; Weaver, K E; Kirsch, J P; Webster, D B

    1995-07-01

    Exogenous administration of GM1 ganglioside to CBA/J mice with a neonatal conductive hearing loss ameliorates the atrophy of spiral ganglion neurons, ventral cochlear nucleus neurons, and ventral cochlear nucleus volume. The present investigation demonstrates the extent of a conductive loss caused by atresia and tests the hypothesis that GM1 ganglioside treatment will ameliorate the conductive hearing loss. Auditory brainstem responses were recorded from four groups of seven mice each: two groups received daily subcutaneous injections of saline (one group had normal hearing; the other had a conductive hearing loss); the other two groups received daily subcutaneous injections of GM1 ganglioside (one group had normal hearing; the other had a conductive hearing loss). In mice with a conductive loss, decreases in hearing sensitivity were greatest at high frequencies. The decreases were determined by comparing mean ABR thresholds of the conductive loss mice with those of normal hearing mice. The conductive hearing loss induced in the mice in this study was similar to that seen in humans with congenital aural atresias. GM1 ganglioside treatment had no significant effect on ABR wave I thresholds or latencies in either group.

  11. Auditory Brainstem Responses to Bone-Conducted Brief Tones in Young Children with Conductive or Sensorineural Hearing Loss

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    Jennifer L. Hatton

    2012-01-01

    Full Text Available The bone-conduction (BC tone ABR has been used clinically for over 20 years. The current study formally evaluated the test performance of the BC tone-evoked ABR in infants with hearing loss. Method. By comparing BC-ABR results to follow-up behavioural results, this study addressed two questions: (i whether the BC tone ABR was successful in differentiating children with conductive versus sensorineural hearing loss (Study A; conductive: 68 ears; SNHL: 129 ears and (ii the relationship between BC ABR and behavioural hearing loss severity (Study B: 2000 Hz: 104 ears; 500 Hz: 47 ears. Results. Results demonstrate that the “normal” BC-ABR levels accurately differentiated normal versus elevated cochlear sensitivity (accuracy: 98% for 2000 Hz; 98% for 500 Hz. A subset of infants in Study A with elevated BC-ABR (i.e., no response at normal level had additional testing at higher intensities, which allowed for categorization of the degree of cochlear impairment. Study B results indicate that the BC ABR accurately categorizes the degree of cochlear hearing loss for 2000 Hz (accuracy = 95.2%. A preliminary dBnHL-to-dBHL correction factor of “0 dB” was determined for 2000 Hz BC ABR. Conclusions. These findings further support the use of BC tone ABR for diagnostic ABR testing.

  12. Auditory Brainstem Responses to Bone-Conducted Brief Tones in Young Children with Conductive or Sensorineural Hearing Loss

    Science.gov (United States)

    Hatton, Jennifer L.; Janssen, Renée M.; Stapells, David R.

    2012-01-01

    The bone-conduction (BC) tone ABR has been used clinically for over 20 years. The current study formally evaluated the test performance of the BC tone-evoked ABR in infants with hearing loss. Method. By comparing BC-ABR results to follow-up behavioural results, this study addressed two questions: (i) whether the BC tone ABR was successful in differentiating children with conductive versus sensorineural hearing loss (Study A; conductive: 68 ears; SNHL: 129 ears) and (ii) the relationship between BC ABR and behavioural hearing loss severity (Study B: 2000 Hz: 104 ears; 500 Hz: 47 ears). Results. Results demonstrate that the “normal” BC-ABR levels accurately differentiated normal versus elevated cochlear sensitivity (accuracy: 98% for 2000 Hz; 98% for 500 Hz). A subset of infants in Study A with elevated BC-ABR (i.e., no response at normal level) had additional testing at higher intensities, which allowed for categorization of the degree of cochlear impairment. Study B results indicate that the BC ABR accurately categorizes the degree of cochlear hearing loss for 2000 Hz (accuracy = 95.2%). A preliminary dBnHL-to-dBHL correction factor of “0 dB” was determined for 2000 Hz BC ABR. Conclusions. These findings further support the use of BC tone ABR for diagnostic ABR testing. PMID:22988461

  13. Brainstem auditory evoked response characteristics in normal-hearing subjects with chronic tinnitus and in non-tinnitus group

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    Shadman Nemati

    2014-06-01

    Full Text Available Background and Aim: While most of the people with tinnitus have some degrees of hearing impairment, a small percent of patients admitted to ear, nose and throat clinics or hearing evaluation centers are those who complain of tinnitus despite having normal hearing thresholds. This study was performed to better understanding of the reasons of probable causes of tinnitus and to investigate possible changes in the auditory brainstem function in normal-hearing patients with chronic tinnitus.Methods: In this comparative cross-sectional, descriptive and analytic study, 52 ears (26 with and 26 without tinnitus were examined. Components of the auditory brainstem response (ABR including wave latencies and wave amplitudes were determined in the two groups and analyzed using appropriate statistical methods.Results: The mean differences between the absolute latencies of waves I, III and V was less than 0.1 ms between the two groups that was not statistically significant. Also, the interpeak latency values of waves I-III, III-V and I-V in both groups had no significant difference. Only, the V/I amplitude ratio in the tinnitus group was significantly higher (p=0.04.Conclusion: The changes observed in amplitude of waves, especially in the latter ones, can be considered as an indication of plastic changes in neuronal activity and its possible role in generation of tinnitus in normal-hearing patients.

  14. Contribution of resolved and unresolved harmonic regions to brainstem speech-evoked responses in quiet and in background noise

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    M. Laroche

    2011-03-01

    Full Text Available Speech auditory brainstem responses (speech ABR reflect activity that is phase-locked to the harmonics of the fundamental frequency (F0 up to at least the first formant (F1. Recent evidence suggests that responses at F0 in the presence of noise are more robust than responses at F1, and are also dissociated in some learning-impaired children. Peripheral auditory processing can be broadly divided into resolved and unresolved harmonic regions. This study investigates the contribution of these two regions to the speech ABR, and their susceptibility to noise. We recorded, in quiet and in background white noise, evoked responses in twelve normal hearing adults in response to three variants of a synthetic vowel: i Allformants, which contains all first three formants, ii F1Only, which is dominated by resolved harmonics, and iii F2&F3Only, which is dominated by unresolved harmonics. There were no statistically significant differences in the response at F0 due to the three variants of the stimulus in quiet, nor did the noise affect this response with the Allformants and F1Only variants. On the other hand, the response at F0 with the F2&F3Only variant was significantly weaker in noise than with the two other variants (p<0.001. With the response at F1, there was no difference with the Allformants and F1Only variants in quiet, but was expectedly weaker with the F2&F3Only variant (p<0.01. The addition of noise significantly weakened the response at F1 with the F1Only variant (p<0.05, but this weakening only tended towards significance with the Allformants variant (p=0.07. The results of this study indicate that resolved and unresolved harmonics are processed in different but interacting pathways that converge in the upper brainstem. The results also support earlier work on the differential susceptibility of responses at F0 and F1 to added noise.

  15. The human auditory brainstem response to running speech reveals a subcortical mechanism for selective attention.

    Science.gov (United States)

    Forte, Antonio Elia; Etard, Octave; Reichenbach, Tobias

    2017-10-10

    Humans excel at selectively listening to a target speaker in background noise such as competing voices. While the encoding of speech in the auditory cortex is modulated by selective attention, it remains debated whether such modulation occurs already in subcortical auditory structures. Investigating the contribution of the human brainstem to attention has, in particular, been hindered by the tiny amplitude of the brainstem response. Its measurement normally requires a large number of repetitions of the same short sound stimuli, which may lead to a loss of attention and to neural adaptation. Here we develop a mathematical method to measure the auditory brainstem response to running speech, an acoustic stimulus that does not repeat and that has a high ecological validity. We employ this method to assess the brainstem's activity when a subject listens to one of two competing speakers, and show that the brainstem response is consistently modulated by attention.

  16. Newborn hearing screening with transient evoked otoacoustic emissions and automatic auditory brainstem response

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    Renata Mota Mamede de Carvallo

    2008-09-01

    Full Text Available Objective: The aim of the present investigation was to check Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests applied together in regular nurseries and Newborn Intensive Care Units (NICU, as well as to describe and compare the results obtained in both groups. Methods: We tested 150 newborns from regular nurseries and 70 from NICU. Rresults: The newborn hearing screening results using Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests could be applied to all babies. The “pass” result for the group of babies from the nursery was 94.7% using Transient Evoked Otoacoustic Emissions and 96% using Automatic Auditory Brainstem Response. The newborn intensive care unit group obtained 87.1% on Transient Evoked Otoacoustic Emissions and 80% on the Automatic Auditory Brainstem Response, and there was no statistical difference between the procedures when the groups were evaluated individually. However, comparing the groups, Transient Evoked Otoacoustic Emissions were presented in 94.7% of the nursery babies and in 87.1% in the group from the newborn intensive care unit. Considering the Automatic Auditory Brainstem Response, we found 96 and 87%, respectively. Cconclusions: Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response had similar “pass” and “fail” results when the procedures were applied to neonates from the regular nursery, and the combined tests were more precise to detect hearing impairment in the newborn intensive care unit babies.

  17. Newborn hearing screening with transient evoked otoacoustic emissions and automatic auditory brainstem response

    OpenAIRE

    Renata Mota Mamede de Carvallo; Carla Gentile Matas; Isabela de Souza Jardim

    2008-01-01

    Objective: The aim of the present investigation was to check Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests applied together in regular nurseries and Newborn Intensive Care Units (NICU), as well as to describe and compare the results obtained in both groups. Methods: We tested 150 newborns from regular nurseries and 70 from NICU. Rresults: The newborn hearing screening results using Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem...

  18. Gender differences in binaural speech-evoked auditory brainstem response: are they clinically significant?

    Science.gov (United States)

    Jalaei, Bahram; Azmi, Mohd Hafiz Afifi Mohd; Zakaria, Mohd Normani

    2018-05-17

    Binaurally evoked auditory evoked potentials have good diagnostic values when testing subjects with central auditory deficits. The literature on speech-evoked auditory brainstem response evoked by binaural stimulation is in fact limited. Gender disparities in speech-evoked auditory brainstem response results have been consistently noted but the magnitude of gender difference has not been reported. The present study aimed to compare the magnitude of gender difference in speech-evoked auditory brainstem response results between monaural and binaural stimulations. A total of 34 healthy Asian adults aged 19-30 years participated in this comparative study. Eighteen of them were females (mean age=23.6±2.3 years) and the remaining sixteen were males (mean age=22.0±2.3 years). For each subject, speech-evoked auditory brainstem response was recorded with the synthesized syllable /da/ presented monaurally and binaurally. While latencies were not affected (p>0.05), the binaural stimulation produced statistically higher speech-evoked auditory brainstem response amplitudes than the monaural stimulation (p0.80), substantive gender differences were noted in most of speech-evoked auditory brainstem response peaks for both stimulation modes. The magnitude of gender difference between the two stimulation modes revealed some distinct patterns. Based on these clinically significant results, gender-specific normative data are highly recommended when using speech-evoked auditory brainstem response for clinical and future applications. The preliminary normative data provided in the present study can serve as the reference for future studies on this test among Asian adults. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  19. O BERA como instrumento de avaliação funcional do tronco cerebral em cirurgias com hipotermia profunda e parada circulatória total The ABR as a tool in the evaluation of brainstem function in surgeries with deep hypothermia and total cardiac arrest

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    Luiz Carlos Alves de Sousa

    2003-10-01

    Full Text Available OBJETIVO: Monitoramento do tronco cerebral através da análise dos traçados do BERA em cirurgia cardíaca com hipotermia profunda e parada circulatória total (PCT, registrando a recuperação funcional (eletrofisiológica do tronco cerebral. FORMA DE ESTUDO: Coorte Longitudinal. MATERIAL E MÉTODO: Foram estudados o comportamento do traçado do BERA de 8 pacientes submetidos a cirurgia cardíaca com hipotermia profunda e PCT para correção de aneurisma de aorta torácica. Etapas: resfriamento corporal até 18ºC C; PCT por até 60 minutos; reaquecimento. Registros do BERA: 35ºC, 32ºC, 26ºC, 18ºC, 27ºC, 35ºC. RESULTADOS: Os traçados iniciais (35ºC se apresentavam normais. Aos 26ºC há o desaparecimento de todas as ondas. Aos 18ºC o traçado do BERA mostrava um padrão isoelétrico. Aos 27ºC, recuperação das ondas I, III e V. A partir de 35ºC as latências das ondas retornam ao normal. CONCLUSÃO: O BERA constitui-se em competente instrumento de monitoramento da integridade funcional do tronco cerebral em cirurgia cardíaca com hipotermia profunda e PCT. As ondas desaparecem no período de resfriamento corporal, atingem um padrão isoelétrico a 18ºC, e reaparecem durante o reaquecimento. No final do procedimento, os médicos anestesistas não dispõem de exame clínico fidedigno para acessar a integridade funcional do tronco cerebral, devido ao uso de drogas depressoras do SNC. O reaparecimento das ondas do BERA é o parâmetro proposto para este fim. A manutenção do padrão isoelétrico após o reaquecimento corporal sugere grave comprometimento funcional do tronco cerebral.AIM: The authors propose the use of ABR as an instrument for the detection of brainstem dysfunction in the trans- and post-operatory period of surgeries with total circulatory arrest (TCA and deep hypothermia for correction of aneurysms of the thoracic aorta. STUDY DESIGN: Longitudinal Cohort. MATERIAL AND METHOD: Eight adult patients that underwent

  20. Speech-evoked brainstem frequency-following responses during verbal transformations due to word repetition.

    Science.gov (United States)

    Galbraith, G C; Jhaveri, S P; Kuo, J

    1997-01-01

    Speech-evoked brainstem frequency-following responses (FFRs) were recorded to repeated presentations of the same stimulus word. Word repetition results in illusory verbal transformations (VTs) in which word perceptions can differ markedly from the actual stimulus. Previous behavioral studies support an explanation of VTs based on changes in arousal or attention. Horizontal and vertical dipole FFRs were recorded to assess responses with putative origins in the auditory nerve and central brainstem, respectively. FFRs were recorded from 18 subjects when they correctly heard the stimulus and when they reported VTs. Although horizontal and vertical dipole FFRs showed different frequency response patterns, dipoles did not differentiate between perceptual conditions. However, when subjects were divided into low- and high-VT groups (based on percentage of VT trials), a significant Condition x Group interaction resulted. This interaction showed the largest difference in FFR amplitudes during VT trials, with the low-VT group showing increased amplitudes, and the high-VT group showing decreased amplitudes, relative to trials in which the stimulus was correctly perceived. These results demonstrate measurable subject differences in the early processing of complex signals, due to possible effects of attention on the brainstem FFR. The present research shows that the FFR is useful in understanding human language as it is coded and processed in the brainstem auditory pathway.

  1. Enhanced brainstem and cortical evoked response amplitudes: single-trial covariance analysis.

    Science.gov (United States)

    Galbraith, G C

    2001-06-01

    The purpose of the present study was to develop analytic procedures that improve the definition of sensory evoked response components. Such procedures could benefit all recordings but would especially benefit difficult recordings where many trials are contaminated by muscle and movement artifacts. First, cross-correlation and latency adjustment analyses were applied to the human brainstem frequency-following response and cortical auditory evoked response recorded on the same trials. Lagged cross-correlation functions were computed, for each of 17 subjects, between single-trial data and templates consisting of the sinusoid stimulus waveform for the brainstem response and the subject's own smoothed averaged evoked response P2 component for the cortical response. Trials were considered in the analysis only if the maximum correlation-squared (r2) exceeded .5 (negatively correlated trials were thus included). Identical correlation coefficients may be based on signals with quite different amplitudes, but it is possible to assess amplitude by the nonnormalized covariance function. Next, an algorithm is applied in which each trial with negative covariance is matched to a trial with similar, but positive, covariance and these matched-trial pairs are deleted. When an evoked response signal is present in the data, the majority of trials positively correlate with the template. Thus, a residual of positively correlated trials remains after matched covariance trials are deleted. When these residual trials are averaged, the resulting brainstem and cortical responses show greatly enhanced amplitudes. This result supports the utility of this analysis technique in clarifying and assessing evoked response signals.

  2. The absence of later wave components in auditory brainstem responses as an initial manifestation of type 2 Gaucher disease.

    Science.gov (United States)

    Okubo, Yusuke; Goto, Masahiro; Sakakibara, Hiroshi; Terakawa, Toshiro; Kaneko, Takashi; Miyama, Sahoko

    2014-12-01

    Type 2 Gaucher disease is the most severe neuronopathic form of Gaucher disease and is characterized by severe neurodegeneration with brainstem involvement and organ failure. Prediction or diagnosis of type 2 Gaucher disease before the development of neurological complications is difficult. A 5-month-old female infant presented with deafness without other neurological abnormalities. Auditory brainstem response analysis revealed the absence of later wave components. Two months later, muscular rigidity became evident, followed by the development of opisthotonus and strabismus. Rapid progression of splenomegaly led to the diagnosis of type 2 Gaucher disease. Abnormal auditory brainstem response findings may already exist before the development of severe brainstem abnormalities such as muscular rigidity and opisthotonus in type 2 Gaucher disease. When patients present with deafness and absent later wave components on auditory brainstem response, type 2 Gaucher disease should be included in the differential diagnosis even in the absence of other neurological abnormalities. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Auditory Site of Lesion in Infants Suffering from Hyperbilirubinemia by Using ABR and TEOAEs

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    Mehdi Akbari

    2006-12-01

    Full Text Available Background and Aim: Hyperbilirubinemia is one of the most common abnormalities during the neonatal period. Approximately 60% full-term and 80% preterm neonates suffer from hyperbilirubinemia. Hearing loss is one of the most prevalent side-effects of hyperbilirubinemia. This happens when the serum concentration of indirect bilirubin increases dramatically. The main purpose of this study is to evaluate the hearing status and to diagnose the probable site of lesion in affected children. Materials and Methods : In this cross-sectional study, 33 newborn to two year old subjects suffering from hyperbilirubinemia were evaluated using auditory brainstem response (ABR and transient evoked otoacoustic emissions (TEOAE tests In the Audiology department of the Faculty of Rehabilitation Sciences Iran University of Medical Sciences sampling method was accessible. Results: 21% of the subjects had severe to profound hearing loss and 9% of subjects had mild to moderate hearing loss. In 15% of the subjects there was no response to ABR and TEOAE tests indicating cochlear and/or retrocochlear lesion. The other 15% manifest only abnormal ABR test indicating the presence of the auditory neuropathy. Conclusion: TEOAE test has its own limitations in these subjects, that is the hearing status of such patients can not be completely evaluated by using just TEOAE test. Therefore, to detect hearing loss both ABR and TEOAE tests must be performed in these subjects.

  4. Selective attention modulates human auditory brainstem responses: relative contributions of frequency and spatial cues.

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    Alexandre Lehmann

    Full Text Available Selective attention is the mechanism that allows focusing one's attention on a particular stimulus while filtering out a range of other stimuli, for instance, on a single conversation in a noisy room. Attending to one sound source rather than another changes activity in the human auditory cortex, but it is unclear whether attention to different acoustic features, such as voice pitch and speaker location, modulates subcortical activity. Studies using a dichotic listening paradigm indicated that auditory brainstem processing may be modulated by the direction of attention. We investigated whether endogenous selective attention to one of two speech signals affects amplitude and phase locking in auditory brainstem responses when the signals were either discriminable by frequency content alone, or by frequency content and spatial location. Frequency-following responses to the speech sounds were significantly modulated in both conditions. The modulation was specific to the task-relevant frequency band. The effect was stronger when both frequency and spatial information were available. Patterns of response were variable between participants, and were correlated with psychophysical discriminability of the stimuli, suggesting that the modulation was biologically relevant. Our results demonstrate that auditory brainstem responses are susceptible to efferent modulation related to behavioral goals. Furthermore they suggest that mechanisms of selective attention actively shape activity at early subcortical processing stages according to task relevance and based on frequency and spatial cues.

  5. Evidence of "hidden hearing loss" following noise exposures that produce robust TTS and ABR wave-I amplitude reductions.

    Science.gov (United States)

    Lobarinas, Edward; Spankovich, Christopher; Le Prell, Colleen G

    2017-06-01

    In animals, noise exposures that produce robust temporary threshold shifts (TTS) can produce immediate damage to afferent synapses and long-term degeneration of low spontaneous rate auditory nerve fibers. This synaptopathic damage has been shown to correlate with reduced auditory brainstem response (ABR) wave-I amplitudes at suprathreshold levels. The perceptual consequences of this "synaptopathy" remain unknown but have been suggested to include compromised hearing performance in competing background noise. Here, we used a modified startle inhibition paradigm to evaluate whether noise exposures that produce robust TTS and ABR wave-I reduction but not permanent threshold shift (PTS) reduced hearing-in-noise performance. Animals exposed to 109 dB SPL octave band noise showed TTS >30 dB 24-h post noise and modest but persistent ABR wave-I reduction 2 weeks post noise despite full recovery of ABR thresholds. Hearing-in-noise performance was negatively affected by the noise exposure. However, the effect was observed only at the poorest signal to noise ratio and was frequency specific. Although TTS >30 dB 24-h post noise was a predictor of functional deficits, there was no relationship between the degree of ABR wave-I reduction and degree of functional impairment. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Turtle Hearing Capability Based on ABR Signal assessment

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    Raja Bidin Raja Hassan

    2010-08-01

    Full Text Available Sea turtles have existed for millions of years. International Union for Conservation of Nature (IUCN has reported that the Hawksbill Turtle (Eretmochelys imbricata is classified as critically endangered. Turtle excluder device (TED deployment on shrimpnet fisheries is needed for turtle conservation.TED using sound technique is challenge method in fisheries development.The knowledge on turtle hearing capability is limited. The auditory brainstem response (ABR assessment is method to determine turtle hearing capability. Turtle hearing assessment is basis to design TED. The objective of this paper is to determine turtle hearing cability by analyze its ABR spectral.The subject is Hawksbill turtle with number 2 turtles ie: 3 and 2 years. The measurement was taken at Pusat Pengurusan Penyu (Turtle Management Centre Padang Kemunting Masjid Tanah Melaka Malaysia. The results shows that turtle 3 years have peak power frequencies 50.78, 101.6, 152.3, 304.7, 355.5, 457, and 507.8Hz respectively whereas the spectral amplitude is ranging 0.03-32.44% spectral. Turtle 2 years has peak power at 457Hz in whole stimulus frequencies while the spectral amplitude is ranging 0.01-2.5% spectral.

  7. Interaction between two cis-acting elements, ABRE and DRE, in ABA-dependent expression of Arabidopsis rd29A gene in response to dehydration and high-salinity stresses.

    Science.gov (United States)

    Narusaka, Yoshihiro; Nakashima, Kazuo; Shinwari, Zabta K; Sakuma, Yoh; Furihata, Takashi; Abe, Hiroshi; Narusaka, Mari; Shinozaki, Kazuo; Yamaguchi-Shinozaki, Kazuko

    2003-04-01

    Many abiotic stress-inducible genes contain two cis-acting elements, namely a dehydration-responsive element (DRE; TACCGACAT) and an ABA-responsive element (ABRE; ACGTGG/TC), in their promoter regions. We precisely analyzed the 120 bp promoter region (-174 to -55) of the Arabidopsis rd29A gene whose expression is induced by dehydration, high-salinity, low-temperature, and abscisic acid (ABA) treatments and whose 120 bp promoter region contains the DRE, DRE/CRT-core motif (A/GCCGAC), and ABRE sequences. Deletion and base substitution analyses of this region showed that the DRE-core motif functions as DRE and that the DRE/DRE-core motif could be a coupling element of ABRE. Gel mobility shift assays revealed that DRE-binding proteins (DREB1s/CBFs and DREB2s) bind to both DRE and the DRE-core motif and that ABRE-binding proteins (AREBs/ABFs) bind to ABRE in the 120 bp promoter region. In addition, transactivation experiments using Arabidopsis leaf protoplasts showed that DREBs and AREBs cumulatively transactivate the expression of a GUS reporter gene fused to the 120 bp promoter region of rd29A. These results indicate that DRE and ABRE are interdependent in the ABA-responsive expression of the rd29A gene in response to ABA in Arabidopsis.

  8. Potenciais evocados auditivos de tronco encefálico em frentistas Auditory brainstem response in gas station attendants

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    Lenita da Silva Quevedo

    2012-12-01

    Full Text Available A ototoxidade dos solventes orgânicos pode atingir o sistema auditivo a nível coclear e retrococlear. OBJETIVO: Avaliar a integridade neurofisiológica do sistema auditivo até tronco cerebral por meio do PEATE. MÉTODO: Estudo prospectivo. Estudados frentistas de três postos de gasolina da cidade de Santa Maria/RS. A amostra ficou composta por 21 sujeitos, que foram avaliados por meio de potenciais evocados auditivos de tronco encefálico. RESULTADOS: Alteração nas latências absolutas das ondas I e III e em todas as latências interpicos, na orelha direita. Na orelha esquerda houve alteração na latência absoluta de todas as ondas, e em todos os intervalos interpicos. Alteração na diferença interaural da onda V foi verificada em 19% dos sujeitos. No grupo exposto há mais de cinco anos, foram estatisticamente significantes o número de sujeitos com alteração: no intervalo interpico I-V da orelha direita; na latência absoluta da onda I e no intervalo interpico III-V da orelha esquerda. CONCLUSÃO: A exposição a combustíveis pode causar alterações no sistema auditivo central.Ototoxicity of organic solvents can affect the hearing system up to the cochlea level and the central structures of hearing. OBJECTIVE: To evaluate the neurophysiological integrity of the hearing system in subjects exposed to fuels using ABR. METHOD: Prospective study. We evaluated attendants from three gas stations in Santa Maria/RS. The sample had 21 subjects, who were evaluated by auditory brainstem response. RESULTS: We found an alteration in the absolute latencies of Waves I and III and in all the interpeak latencies, in the right ear. In the left ear there was a change in the absolute latencies of all Waves, and in all the interpeak intervals. A change in the interaural difference of Wave V was found in 19% of the individuals. In the group exposed for more than five years, there were subjects with a statistically significant changes: in the I

  9. DESCRIPTION OF BRAINSTEM AUDITORY EVOKED RESPONSES (AIR AND BONE CONDUCTION IN CHILDREN WITH NORMAL HEARING

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    A. V. Pashkov

    2014-01-01

    Full Text Available Diagnosis of hearing level in small children with conductive hearing loss associated with congenital craniofacial abnormalities, particularly with agenesis of external ear and external auditory meatus is a pressing issue. Conventional methods of assessing hearing in the first years of life, i. e. registration of brainstem auditory evoked responses to acoustic stimuli in the event of air conduction, does not give an indication of the auditory analyzer’s condition due to potential conductive hearing loss in these patients. This study was aimed at assessing potential of diagnosing the auditory analyzer’s function with registering brainstem auditory evoked responses (BAERs to acoustic stimuli transmitted by means of a bone vibrator. The study involved 17 children aged 3–10 years with normal hearing. We compared parameters of registering brainstem auditory evoked responses (peak V depending on the type of stimulus transmission (air/bone in children with normal hearing. The data on thresholds of the BAERs registered to acoustic stimuli in the event of air and bone conduction obtained in this study are comparable; hearing thresholds in the event of acoustic stimulation by means of a bone vibrator correlates with the results of the BAERs registered to the stimuli transmitted by means of air conduction earphones (r = 0.9. High correlation of thresholds of BAERs to the stimuli transmitted by means of a bone vibrator with thresholds of BAERs registered when air conduction earphones were used helps to assess auditory analyzer’s condition in patients with any form of conductive hearing loss.  

  10. Impact of monaural frequency compression on binaural fusion at the brainstem level.

    Science.gov (United States)

    Klauke, Isabelle; Kohl, Manuel C; Hannemann, Ronny; Kornagel, Ulrich; Strauss, Daniel J; Corona-Strauss, Farah I

    2015-08-01

    A classical objective measure for binaural fusion at the brainstem level is the so-called β-wave of the binaural interaction component (BIC) in the auditory brainstem response (ABR). However, in some cases it appeared that a reliable detection of this component still remains a challenge. In this study, we investigate the wavelet phase synchronization stability (WPSS) of ABR data for the analysis of binaural fusion and compare it to the BIC. In particular, we examine the impact of monaural nonlinear frequency compression on binaural fusion. As the auditory system is tonotopically organized, an interaural frequency mismatch caused by monaural frequency compression could negatively effect binaural fusion. In this study, only few subjects showed a detectable β-wave and in most cases only for low ITDs. However, we present a novel objective measure for binaural fusion that outperforms the current state-of-the-art technique (BIC): the WPSS analysis showed a significant difference between the phase stability of the sum of the monaurally evoked responses and the phase stability of the binaurally evoked ABR. This difference could be an indicator for binaural fusion in the brainstem. Furthermore, we observed that monaural frequency compression could indeed effect binaural fusion, as the WPSS results for this condition vary strongly from the results obtained without frequency compression.

  11. for ABR Service

    Directory of Open Access Journals (Sweden)

    Mohsen Hosamo

    2012-01-01

    Full Text Available This paper describes modeling of the available bit rate (ABR source traffic in asynchronous transfer mode (ATM network using BLPos/GTEXP traffic generator, which employs Poisson distribution for modeling the burst length (BLPos and exponential distribution for modeling the gap time (GTEXP. This traffic generator inherits the advantages of both Poisson and exponential distribution functions to achieve enhanced link performance. Analytical and simulation results for BLPos/GTEXP traffic generator have been presented and compared.

  12. Protective Effects of α-Tocopherol on ABR Threshold Shift in Rabbits Exposed to Noise and Carbon Monoxide.

    Science.gov (United States)

    Motallebi Kashani, Masoud; Mortazavi, Seyyed Bagher; Khavanin, Ali; Allameh, Abdolamir; Mirzaee, Ramezan; Akbari, Mehdi

    2011-01-01

    Noise induced hearin gloss (NIHL) is one of the most important occupational disease world wide. NIHL has been found potentiate by simultaneous carbon monoxide (CO) exposure. Free radicals have been implicated in cochlear damage resulted from the exposure to noise and due to the CO hypoxia. This study examined whether α-tocopherol administration , as a free radical scavenger, causes the attenuation of auditory brainstem response (ABR) threshold shifts resulting from noise exposure and noise plus CO exposure. Forty-two rabbits were divided in to seven groups including control, noise + saline, noise + CO + saline, noise + α-tocopherol, noise + CO + α-tocopherol , CO + α-tocopherol and α-tocopherol alone. ABR was assessed before exposure, 1 hand 14 days post exposure. The administration of 50 mg/Kg of α-tocopherol prior, following and post exposure to noise or noise plus CO recovered permanent ABR threshold shift at 1 and KHz almost to the baseline and provided significant attenuation in permanent ABR threshold shift at 4 and 8 KHz in subject swhich were exposed to noise but it did not block the potentiating of threshold elevation by CO exposure (extra threshold loss by combined exposure) at 4 and 8 KHz. α Tocopherol provides protective effect against the hearing loss resulting from noise exposure and simultaneous exposure to noise plus CO.

  13. An ABRE promoter sequence is involved in osmotic stress-responsive expression of the DREB2A gene, which encodes a transcription factor regulating drought-inducible genes in Arabidopsis.

    Science.gov (United States)

    Kim, June-Sik; Mizoi, Junya; Yoshida, Takuya; Fujita, Yasunari; Nakajima, Jun; Ohori, Teppei; Todaka, Daisuke; Nakashima, Kazuo; Hirayama, Takashi; Shinozaki, Kazuo; Yamaguchi-Shinozaki, Kazuko

    2011-12-01

    In plants, osmotic stress-responsive transcriptional regulation depends mainly on two major classes of cis-acting elements found in the promoter regions of stress-inducible genes: ABA-responsive elements (ABREs) and dehydration-responsive elements (DREs). ABRE has been shown to perceive ABA-mediated osmotic stress signals, whereas DRE is known to be involved in an ABA-independent pathway. Previously, we reported that the transcription factor DRE-BINDING PROTEIN 2A (DREB2A) regulates DRE-mediated transcription of target genes under osmotic stress conditions in Arabidopsis (Arabidopsis thaliana). However, the transcriptional regulation of DREB2A itself remains largely uncharacterized. To elucidate the transcriptional mechanism associated with the DREB2A gene under osmotic stress conditions, we generated a series of truncated and base-substituted variants of the DREB2A promoter and evaluated their transcriptional activities individually. We found that both ABRE and coupling element 3 (CE3)-like sequences located approximately -100 bp from the transcriptional initiation site are necessary for the dehydration-responsive expression of DREB2A. Coupling our transient expression analyses with yeast one-hybrid and chromatin immunoprecipitation (ChIP) assays indicated that the ABRE-BINDING PROTEIN 1 (AREB1), AREB2 and ABRE-BINDING FACTOR 3 (ABF3) bZIP transcription factors can bind to and activate the DREB2A promoter in an ABRE-dependent manner. Exogenous ABA application induced only a modest accumulation of the DREB2A transcript when compared with the osmotic stress treatment. However, the osmotic stress-induced DREB2A expression was found to be markedly impaired in several ABA-deficient and ABA-insensitive mutants. These results suggest that in addition to an ABA-independent pathway, the ABA-dependent pathway plays a positive role in the osmotic stress-responsive expression of DREB2A.

  14. Effect of hearing aids use on speech stimulus decoding through speech-evoked ABR

    Directory of Open Access Journals (Sweden)

    Renata Aparecida Leite

    Full Text Available Abstract Introduction The electrophysiological responses obtained with the complex auditory brainstem response (cABR provide objective measures of subcortical processing of speech and other complex stimuli. The cABR has also been used to verify the plasticity in the auditory pathway in the subcortical regions. Objective To compare the results of cABR obtained in children using hearing aids before and after 9 months of adaptation, as well as to compare the results of these children with those obtained in children with normal hearing. Methods Fourteen children with normal hearing (Control Group - CG and 18 children with mild to moderate bilateral sensorineural hearing loss (Study Group - SG, aged 7-12 years, were evaluated. The children were submitted to pure tone and vocal audiometry, acoustic immittance measurements and ABR with speech stimulus, being submitted to the evaluations at three different moments: initial evaluation (M0, 3 months after the initial evaluation (M3 and 9 months after the evaluation (M9; at M0, the children assessed in the study group did not use hearing aids yet. Results When comparing the CG and the SG, it was observed that the SG had a lower median for the V-A amplitude at M0 and M3, lower median for the latency of the component V at M9 and a higher median for the latency of component O at M3 and M9. A reduction in the latency of component A at M9 was observed in the SG. Conclusion Children with mild to moderate hearing loss showed speech stimulus processing deficits and the main impairment is related to the decoding of the transient portion of this stimulus spectrum. It was demonstrated that the use of hearing aids promoted neuronal plasticity of the Central Auditory Nervous System after an extended time of sensory stimulation.

  15. Thresholds of Tone Burst Auditory Brainstem Responses for Infants and Young Children with Normal Hearing in Taiwan

    Directory of Open Access Journals (Sweden)

    Chung-Yi Lee

    2007-10-01

    Conclusion: Based on the published research and our study, we suggest setting the normal criterion levels for infants and young children in Taiwan of the tone burst auditory brainstem response to air-conducted tones as 30 dB nHL for 500 and 1000 Hz, and 25 dB nHL for 2000 and 4000 Hz.

  16. Comparison between chloral hydrate and propofol-ketamine as sedation regimens for pediatric auditory brainstem response testing.

    Science.gov (United States)

    Abulebda, Kamal; Patel, Vinit J; Ahmed, Sheikh S; Tori, Alvaro J; Lutfi, Riad; Abu-Sultaneh, Samer

    2017-10-28

    The use of diagnostic auditory brainstem response testing under sedation is currently the "gold standard" in infants and young children who are not developmentally capable of completing the test. The aim of the study is to compare a propofol-ketamine regimen to an oral chloral hydrate regimen for sedating children undergoing auditory brainstem response testing. Patients between 4 months and 6 years who required sedation for auditory brainstem response testing were included in this retrospective study. Drugs doses, adverse effects, sedation times, and the effectiveness of the sedative regimens were reviewed. 73 patients underwent oral chloral hydrate sedation, while 117 received propofol-ketamine sedation. 12% of the patients in the chloral hydrate group failed to achieve desired sedation level. The average procedure, recovery and total nursing times were significantly lower in the propofol-ketamine group. Propofol-ketamine group experienced higher incidence of transient hypoxemia. Both sedation regimens can be successfully used for sedating children undergoing auditory brainstem response testing. While deep sedation using propofol-ketamine regimen offers more efficiency than moderate sedation using chloral hydrate, it does carry a higher incidence of transient hypoxemia, which warrants the use of a highly skilled team trained in pediatric cardio-respiratory monitoring and airway management. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  17. Enhanced auditory brainstem response and parental bonding style in children with gastrointestinal symptoms.

    Directory of Open Access Journals (Sweden)

    Shizuka Seino

    Full Text Available The electrophysiological properties of the brain and influence of parental bonding in childhood irritable bowel syndrome (IBS are unclear. We hypothesized that children with chronic gastrointestinal (GI symptoms like IBS may show exaggerated brainstem auditory evoked potential (BAEP responses and receive more inadequate parental bonding.Children aged seven and their mothers (141 pairs participated. BAEP was measured by summation of 1,000 waves of the electroencephalogram triggered by 75 dB click sounds. The mothers completed their Children's Somatization Inventory (CSI and Parental Bonding Instrument (PBI. CSI results revealed 66 (42% children without GI symptoms (controls and 75 (58% children with one or more GI symptoms (GI group. The III wave in the GI group (median 4.10 interquartile range [3.95-4.24] ms right, 4.04 [3.90-4.18] ms left had a significantly shorter peak latency than controls (4.18 [4.06-4.34] ms right, p = 0.032, 4.13 [4.02-4.24] ms left, p = 0.018. The female GI group showed a significantly shorter peak latency of the III wave (4.00 [3.90-4.18] ms than controls (4.18 [3.97-4.31] ms, p = 0.034 in the right side. BAEP in the male GI group did not significantly differ from that in controls. GI scores showed a significant correlation with the peak latency of the III wave in the left side (rho = -0.192, p = 0.025. The maternal care PBI scores in the GI group (29 [26]-[33] were significantly lower than controls (31 [28.5-33], p = 0.010, while the maternal over-protection PBI scores were significantly higher in the GI group (16 [12]-[17] than controls (13 [10.5-16], p = 0.024. Multiple regression analysis in females also supported these findings.It is suggested that children with chronic GI symptoms have exaggerated brainstem responses to environmental stimuli and inadequate parental behaviors aggravate these symptoms.

  18. Synchronized Progression of Prestin Expression and Auditory Brainstem Response during Postnatal Development in Rats

    Directory of Open Access Journals (Sweden)

    Jianfeng Hang

    2016-01-01

    Full Text Available Prestin is the motor protein expressed in the cochlear outer hair cells (OHCs of mammalian inner ear. The electromotility of OHCs driven by prestin is responsible for the cochlear amplification which is required for normal hearing in adult animals. Postnatal expression of prestin and activity of OHCs may contribute to the maturation of hearing in rodents. However, the temporal and spatial expression of prestin in cochlea during the development is not well characterized. In the present study, we examined the expression and function of prestin from the OHCs in apical, middle, and basal turns of the cochleae of postnatal rats. Prestin first appeared at postnatal day 6 (P6 for basal turn, P7 in middle turn, and P9 for apical turn of cochlea. The expression level increased progressively over the next few days and by P14 reached the mature level for all three segments. By comparison with the time course of the development of auditory brainstem response for different frequencies, our data reveal that prestin expression synchronized with the hearing development. The present study suggests that the onset time of hearing may require the expression of prestin and is determined by the mature function of OHCs.

  19. Auditory Brainstem Response Wave Amplitude Characteristics as a Diagnostic Tool in Children with Speech Delay with Unknown Causes

    Directory of Open Access Journals (Sweden)

    Susan Abadi

    2016-09-01

    Full Text Available Speech delay with an unknown cause is a problem among children. This diagnosis is the last differential diagnosis after observing normal findings in routine hearing tests. The present study was undertaken to determine whether auditory brainstem responses to click stimuli are different between normally developing children and children suffering from delayed speech with unknown causes. In this cross-sectional study, we compared click auditory brainstem responses between 261 children who were clinically diagnosed with delayed speech with unknown causes based on normal routine auditory test findings and neurological examinations and had >12 months of speech delay (case group and 261 age- and sex-matched normally developing children (control group. Our results indicated that the case group exhibited significantly higher wave amplitude responses to click stimuli (waves I, III, and V than did the control group (P=0.001. These amplitudes were significantly reduced after 1 year (P=0.001; however, they were still significantly higher than those of the control group (P=0.001. The significant differences were seen regardless of the age and the sex of the participants. There were no statistically significant differences between the 2 groups considering the latency of waves I, III, and V. In conclusion, the higher amplitudes of waves I, III, and V, which were observed in the auditory brainstem responses to click stimuli among the patients with speech delay with unknown causes, might be used as a diagnostic tool to track patients’ improvement after treatment.

  20. Stereotactic Radiosurgery for Brainstem Metastases: An International Cooperative Study to Define Response and Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Trifiletti, Daniel M., E-mail: daniel.trifiletti@gmail.com [Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia (United States); Lee, Cheng-Chia [Department of Neurosurgery, Neurological Institute, Taipei Veteran General Hospital, Taipei, Taiwan (China); Kano, Hideyuki; Cohen, Jonathan [Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Janopaul-Naylor, James; Alonso-Basanta, Michelle; Lee, John Y.K. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Simonova, Gabriela; Liscak, Roman [Department of Radiation and Stereotactic Neurosurgery, Na Homolce Hospital, Prague (Czech Republic); Wolf, Amparo; Kvint, Svetlana [Department of Neurosurgery, New York University Lagone Medical Center, New York, New York (United States); Grills, Inga S.; Johnson, Matthew [Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan (United States); Liu, Kang-Du; Lin, Chung-Jung [Department of Neurosurgery, Neurological Institute, Taipei Veteran General Hospital, Taipei, Taiwan (China); Mathieu, David; Héroux, France [Division of Neurosurgery, Université de Sherbrooke, Centre de recherche du CHUS, Sherbrooke, Québec (Canada); Silva, Danilo; Sharma, Mayur [Department of Neurosurgery, Cleveland Clinic, Cleveland, Ohio (United States); Cifarelli, Christopher P. [Departments of Neurosurgery and Radiation Oncology, West Virginia University, Morgantown, West Virginia (United States); and others

    2016-10-01

    Purpose: To pool data across multiple institutions internationally and report on the cumulative experience of brainstem stereotactic radiosurgery (SRS). Methods and Materials: Data on patients with brainstem metastases treated with SRS were collected through the International Gamma Knife Research Foundation. Clinical, radiographic, and dosimetric characteristics were compared for factors prognostic for local control (LC) and overall survival (OS) using univariate and multivariate analyses. Results: Of 547 patients with 596 brainstem metastases treated with SRS, treatment of 7.4% of tumors resulted in severe SRS-induced toxicity (grade ≥3, increased odds with increasing tumor volume, margin dose, and whole-brain irradiation). Local control at 12 months after SRS was 81.8% and was improved with increasing margin dose and maximum dose. Overall survival at 12 months after SRS was 32.7% and impacted by age, gender, number of metastases, tumor histology, and performance score. Conclusions: Our study provides additional evidence that SRS has become an option for patients with brainstem metastases, with an excellent benefit-to-risk ratio in the hands of experienced clinicians. Prior whole-brain irradiation increases the risk of severe toxicity in brainstem metastasis patients undergoing SRS.

  1. Objective measures for detecting the auditory brainstem response: comparisons of specificity, sensitivity and detection time

    DEFF Research Database (Denmark)

    Chesnaye, M. A.; Bell, S. L.; Harte, J. M.

    2018-01-01

    of the Hotelling's T-2 test (applied in either time or frequency domain), two versions of the modified q-sample uniform scores test and both the Fsp and Fmp, which were evaluated using both conventional F-distributions with assumed degrees of freedom and a bootstrap approach. Study sample: Data consisted of click......-level when evaluating statistical significance using the bootstrap approach, as opposed to using conventional F-distributions. The FPRs of the remaining methods were slightly higher than expected. Conclusions: In this work, Hotelling's T-2 outperformed the alternative methods for automatically detecting ABRs......-evoked ABRs and recordings of EEG background activity from 12 to 17 normal hearing adults, respectively. Results: An overall advantage in sensitivity and detection time was demonstrated for the Hotelling's T-2 test. The false-positive rates (FPRs) of the Fsp and Fmp were also closer to the nominal alpha...

  2. Genome-wide analysis of ABA-responsive elements ABRE and CE3 reveals divergent patterns in Arabidopsis and rice

    OpenAIRE

    Riaño-Pachón Diego; Gómez-Porras Judith L; Dreyer Ingo; Mayer Jorge E; Mueller-Roeber Bernd

    2007-01-01

    Abstract Background In plants, complex regulatory mechanisms are at the core of physiological and developmental processes. The phytohormone abscisic acid (ABA) is involved in the regulation of various such processes, including stomatal closure, seed and bud dormancy, and physiological responses to cold, drought and salinity stress. The underlying tissue or plant-wide control circuits often include combinatorial gene regulatory mechanisms and networks that we are only beginning to unravel with...

  3. Brainstem auditory evoked responses in an equine patient population: part I--adult horses.

    Science.gov (United States)

    Aleman, M; Holliday, T A; Nieto, J E; Williams, D C

    2014-01-01

    Brainstem auditory evoked response has been an underused diagnostic modality in horses as evidenced by few reports on the subject. To describe BAER findings, common clinical signs, and causes of hearing loss in adult horses. Study group, 76 horses; control group, 8 horses. Retrospective. BAER records from the Clinical Neurophysiology Laboratory were reviewed from the years of 1982 to 2013. Peak latencies, amplitudes, and interpeak intervals were measured when visible. Horses were grouped under disease categories. Descriptive statistics and a posthoc Bonferroni test were performed. Fifty-seven of 76 horses had BAER deficits. There was no breed or sex predisposition, with the exception of American Paint horses diagnosed with congenital sensorineural deafness. Eighty-six percent (n = 49/57) of the horses were younger than 16 years of age. The most common causes of BAER abnormalities were temporohyoid osteoarthropathy (THO, n = 20/20; abnormalities/total), congenital sensorineural deafness in Paint horses (17/17), multifocal brain disease (13/16), and otitis media/interna (4/4). Auditory loss was bilateral and unilateral in 74% (n = 42/57) and 26% (n = 15/57) of the horses, respectively. The most common causes of bilateral auditory loss were sensorineural deafness, THO, and multifocal brain disease whereas THO and otitis were the most common causes of unilateral deficits. Auditory deficits should be investigated in horses with altered behavior, THO, multifocal brain disease, otitis, and in horses with certain coat and eye color patterns. BAER testing is an objective and noninvasive diagnostic modality to assess auditory function in horses. Copyright © 2014 by the American College of Veterinary Internal Medicine.

  4. Modeling human auditory evoked brainstem responses based on nonlinear cochlear processing

    DEFF Research Database (Denmark)

    Harte, James; Rønne, Filip Munch; Dau, Torsten

    2010-01-01

    . To generate AEPs recorded at remote locations, a convolution was made on an empirically obtained elementary unit waveform with the instantaneous discharge rate function for the corresponding AN unit. AEPs to click-trains, as well as to tone pulses at various frequencies, were both modelled and recorded...... at different stimulation levels and repetition rates. The observed nonlinearities in the recorded potential patterns, with respect to ABR wave V latencies and amplitudes, could be largely accounted for by level-dependent BM processing as well as effects of short-term neural adaptation. The present study...

  5. ABR Examinations: The Why, What, and How

    International Nuclear Information System (INIS)

    Becker, Gary J.; Bosma, Jennifer L.; Guiberteau, Milton J.; Gerdeman, Anthony M.; Frush, Donald P.; Borgstede, James P.

    2013-01-01

    The American Board of Radiology (ABR) has provided certification for diagnostic radiologists and other specialists and subspecialists for more than 75 years. The Board certification process is a tangible expression of the social contract between the profession and the public by which the profession enjoys the privilege of self-regulation and the public is assured that it can expect medical professionals to put patients' interests first, guarantees the competence of practitioners, and guards the public health. A primary tool used by the ABR in fulfilling this responsibility is the secure proctored examination. This article sets forth seven standards based on authoritative sources in the field of psychometrics (the science of mental measurements), and explains in each case how the ABR implements that standard. Readers are encouraged to understand that, despite the multiple opinions that may be held, these standards developed over decades by experts using the scientific method should be the central feature in any discussion or critique of examinations given for the privilege of professional practice and for safeguarding the public well-being

  6. ABR Examinations: The Why, What, and How

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Gary J.; Bosma, Jennifer L., E-mail: jbosma@theabr.org; Guiberteau, Milton J.; Gerdeman, Anthony M.; Frush, Donald P.; Borgstede, James P.

    2013-10-01

    The American Board of Radiology (ABR) has provided certification for diagnostic radiologists and other specialists and subspecialists for more than 75 years. The Board certification process is a tangible expression of the social contract between the profession and the public by which the profession enjoys the privilege of self-regulation and the public is assured that it can expect medical professionals to put patients' interests first, guarantees the competence of practitioners, and guards the public health. A primary tool used by the ABR in fulfilling this responsibility is the secure proctored examination. This article sets forth seven standards based on authoritative sources in the field of psychometrics (the science of mental measurements), and explains in each case how the ABR implements that standard. Readers are encouraged to understand that, despite the multiple opinions that may be held, these standards developed over decades by experts using the scientific method should be the central feature in any discussion or critique of examinations given for the privilege of professional practice and for safeguarding the public well-being.

  7. Combined laryngeal inflammation and trauma mediate long-lasting immunoreactivity response in the brainstem sensory nuclei in the rat

    Directory of Open Access Journals (Sweden)

    Kristina eSimonyan

    2012-11-01

    Full Text Available Somatosensory feedback from the larynx plays a critical role in regulation of normal upper airway functions, such as breathing, deglutition and voice production, while altered laryngeal sensory feedback is known to elicit a variety of pathological reflex responses, including persistent coughing, dysphonia and laryngospasm. Despite its clinical impact, the central mechanisms underlying the development of pathological laryngeal responses remain poorly understood. We examined the effects of persistent vocal fold (VF inflammation and trauma, as frequent causes of long-lasting modulation of laryngeal sensory feedback, on brainstem immunoreactivity in the rat. Combined VF inflammation and trauma were induced by injection of lipopolysaccharide (LPS solution and compared to VF trauma alone from injection of vehicle solution and to controls without any VF manipulations. Using a c-fos marker, we found significantly increased Fos-like immunoreactivity (FLI in the bilateral intermediate/parvicellular reticular formation (IRF/PCRF with a trend in the left solitary tract nucleus (NTS only in animals with LPS-induced VF inflammation and trauma. Further, FLI in the right NTS was significantly correlated with the severity of LPS-induced VF changes. However, increased brainstem FLI response was not associated with FLI changes in the first-order neurons of the laryngeal afferents located in the nodose and jugular ganglia in either group. Our data indicate that complex VF alterations (i.e., inflammation/trauma vs. trauma alone may cause prolonged excitability of the brainstem nuclei receiving a direct sensory input from the larynx, which, in turn, may lead to (malplastic changes within the laryngeal central sensory control.

  8. Neonatal hearing screening of high-risk infants using automated auditory brainstem response: a retrospective analysis of referral rates.

    LENUS (Irish Health Repository)

    McGurgan, I J

    2013-10-07

    The past decade has seen the widespread introduction of universal neonatal hearing screening (UNHS) programmes worldwide. Regrettably, such a programme is only now in the process of nationwide implementation in the Republic of Ireland and has been largely restricted to one screening modality for initial testing; namely transient evoked otoacoustic emissions (TEOAE). The aim of this study is to analyse the effects of employing a different screening protocol which utilises an alternative initial test, automated auditory brainstem response (AABR), on referral rates to specialist audiology services.

  9. Loud Music Exposure and Cochlear Synaptopathy in Young Adults: Isolated Auditory Brainstem Response Effects but No Perceptual Consequences.

    Science.gov (United States)

    Grose, John H; Buss, Emily; Hall, Joseph W

    2017-01-01

    The purpose of this study was to test the hypothesis that listeners with frequent exposure to loud music exhibit deficits in suprathreshold auditory performance consistent with cochlear synaptopathy. Young adults with normal audiograms were recruited who either did ( n = 31) or did not ( n = 30) have a history of frequent attendance at loud music venues where the typical sound levels could be expected to result in temporary threshold shifts. A test battery was administered that comprised three sets of procedures: (a) electrophysiological tests including distortion product otoacoustic emissions, auditory brainstem responses, envelope following responses, and the acoustic change complex evoked by an interaural phase inversion; (b) psychoacoustic tests including temporal modulation detection, spectral modulation detection, and sensitivity to interaural phase; and (c) speech tests including filtered phoneme recognition and speech-in-noise recognition. The results demonstrated that a history of loud music exposure can lead to a profile of peripheral auditory function that is consistent with an interpretation of cochlear synaptopathy in humans, namely, modestly abnormal auditory brainstem response Wave I/Wave V ratios in the presence of normal distortion product otoacoustic emissions and normal audiometric thresholds. However, there were no other electrophysiological, psychophysical, or speech perception effects. The absence of any behavioral effects in suprathreshold sound processing indicated that, even if cochlear synaptopathy is a valid pathophysiological condition in humans, its perceptual sequelae are either too diffuse or too inconsequential to permit a simple differential diagnosis of hidden hearing loss.

  10. Brainstem disconnection

    International Nuclear Information System (INIS)

    Duffield, Curtis; Wootton-Gorges, Sandra L.; Jocson, Jennifer

    2009-01-01

    Brainstem disconnection is a very rare neonatal abnormality, with only seven cases reported. We report a unique case of a neonate who presented at delivery with hypertonia, dysmorphic facial features, and respiratory distress, as well as numerous musculoskeletal and genitourinary abnormalities. MRI of the brain showed disconnection between the pons and medulla with cerebellar hypoplasia and absent cerebellar peduncles. It aided in the description of the neurological and vascular anomalies associated with this diagnosis. (orig.)

  11. Brainstem disconnection

    Energy Technology Data Exchange (ETDEWEB)

    Duffield, Curtis; Wootton-Gorges, Sandra L. [University of California Davis, Medical Center and UC Davis Children' s Hospital, Department of Radiology, Sacramento, CA (United States); Jocson, Jennifer [University of California Davis, Medical Center and UC Davis Children' s Hospital, Department of Pediatrics, Sacramento, CA (United States)

    2009-12-15

    Brainstem disconnection is a very rare neonatal abnormality, with only seven cases reported. We report a unique case of a neonate who presented at delivery with hypertonia, dysmorphic facial features, and respiratory distress, as well as numerous musculoskeletal and genitourinary abnormalities. MRI of the brain showed disconnection between the pons and medulla with cerebellar hypoplasia and absent cerebellar peduncles. It aided in the description of the neurological and vascular anomalies associated with this diagnosis. (orig.)

  12. Lateralization and Binaural Interaction of Middle-Latency and Late-Brainstem Components of the Auditory Evoked Response.

    Science.gov (United States)

    Dykstra, Andrew R; Burchard, Daniel; Starzynski, Christian; Riedel, Helmut; Rupp, Andre; Gutschalk, Alexander

    2016-08-01

    We used magnetoencephalography to examine lateralization and binaural interaction of the middle-latency and late-brainstem components of the auditory evoked response (the MLR and SN10, respectively). Click stimuli were presented either monaurally, or binaurally with left- or right-leading interaural time differences (ITDs). While early MLR components, including the N19 and P30, were larger for monaural stimuli presented contralaterally (by approximately 30 and 36 % in the left and right hemispheres, respectively), later components, including the N40 and P50, were larger ipsilaterally. In contrast, MLRs elicited by binaural clicks with left- or right-leading ITDs did not differ. Depending on filter settings, weak binaural interaction could be observed as early as the P13 but was clearly much larger for later components, beginning at the P30, indicating some degree of binaural linearity up to early stages of cortical processing. The SN10, an obscure late-brainstem component, was observed consistently in individuals and showed linear binaural additivity. The results indicate that while the MLR is lateralized in response to monaural stimuli-and not ITDs-this lateralization reverses from primarily contralateral to primarily ipsilateral as early as 40 ms post stimulus and is never as large as that seen with fMRI.

  13. Correlation of augmented startle reflex with brainstem electrophysiological responses in Tay-Sachs disease.

    Science.gov (United States)

    Nakamura, Sadao; Saito, Yoshiaki; Ishiyama, Akihiko; Sugai, Kenji; Iso, Takashi; Inagaki, Masumi; Sasaki, Masayuki

    2015-01-01

    To clarify the evolution of an augmented startle reflex in Tay-Sachs disease and compare the temporal relationship between this reflex and brainstem evoked potentials. Clinical and electrophysiological data from 3 patients with Tay-Sachs disease were retrospectively collected. The augmented startle reflex appeared between the age of 3 and 17 months and disappeared between the age of 4 and 6 years. Analysis of brainstem auditory evoked potentials revealed that poor segregation of peak I, but not peak III, coincided with the disappearance of the augmented startle reflex. A blink reflex with markedly high amplitude was observed in a patient with an augmented startle reflex. The correlation between the augmented startle reflex and the preservation of peak I but not peak III supports the theory that the superior olivary nucleus is dispensable for this reflex. The blink reflex with high amplitudes may represent augmented excitability of reticular formation at the pontine tegmentum in Tay-Sachs disease, where the pattern generators for the augmented startle and blink reflexes may functionally overlap. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  14. Brainstem evoked response audiometry: an investigatory tool in detecting hepatic encephalopathy in decompensated chronic liver disease.

    Science.gov (United States)

    Kabali, Balasubramanian; Velayutham, Gowri; Kapali, Suresh Chander

    2014-01-01

    It is estimated that globally there is a marked increase in liver disease with reports of rising morbidity and mortality, particularly in younger age groups. Brainstem auditory evoked potential (BAEP) was recorded in 60 decompensated chronic liver disease (DCLD) subjects who fulfilled the selection criteria and compared to 60 age and gender matched healthy subjects with normal liver functions. DCLD subjects were divided into two inter groups based on presence or absence of hepatic encephalopathy (HE). Group 1 comprises of 30 subjects of grade- I HE and Group 2 included 30 subjects without hepatic encephalopathy (NHE). Absolute and interpeak wave latencies were measured. Results were analysed by student independent t- test using SPSS software 11 version. Statistical significance was tested using P value. From the present study it can be concluded that the central nervous system is involved in liver cirrhosis evidenced by an abnormal BAEP latencies parameters. This shows that there may be progressive demyelination occurring along with axonal loss or dysfunction in liver cirrhosis HE. This study suggests that periodic evaluation of cirrhotic individuals to such test will help in monitoring the progress of encephalopathy. The prime goal of this study is early diagnosis and initiation of treatment before the onset of coma can reduce the fatality rate.

  15. Age-related hearing loss in dogs : Diagnosis with Brainstem-Evoked Response Audiometry and Treatment with Vibrant Soundbridge Middle Ear Implant.

    NARCIS (Netherlands)

    ter Haar, G.

    2009-01-01

    Age-related hearing loss (ARHL) is the most common cause of acquired hearing impairment in dogs. Diagnosis requires objective electrophysiological tests (brainstem evoked response audiometry [BERA]) evaluating the entire audible frequency range in dogs. In our laboratory a method was developed to

  16. Brainstem auditory evoked potentials with the use of acoustic clicks and complex verbal sounds in young adults with learning disabilities.

    Science.gov (United States)

    Kouni, Sophia N; Giannopoulos, Sotirios; Ziavra, Nausika; Koutsojannis, Constantinos

    2013-01-01

    Acoustic signals are transmitted through the external and middle ear mechanically to the cochlea where they are transduced into electrical impulse for further transmission via the auditory nerve. The auditory nerve encodes the acoustic sounds that are conveyed to the auditory brainstem. Multiple brainstem nuclei, the cochlea, the midbrain, the thalamus, and the cortex constitute the central auditory system. In clinical practice, auditory brainstem responses (ABRs) to simple stimuli such as click or tones are widely used. Recently, complex stimuli or complex auditory brain responses (cABRs), such as monosyllabic speech stimuli and music, are being used as a tool to study the brainstem processing of speech sounds. We have used the classic 'click' as well as, for the first time, the artificial successive complex stimuli 'ba', which constitutes the Greek word 'baba' corresponding to the English 'daddy'. Twenty young adults institutionally diagnosed as dyslexic (10 subjects) or light dyslexic (10 subjects) comprised the diseased group. Twenty sex-, age-, education-, hearing sensitivity-, and IQ-matched normal subjects comprised the control group. Measurements included the absolute latencies of waves I through V, the interpeak latencies elicited by the classical acoustic click, the negative peak latencies of A and C waves, as well as the interpeak latencies of A-C elicited by the verbal stimulus 'baba' created on a digital speech synthesizer. The absolute peak latencies of waves I, III, and V in response to monoaural rarefaction clicks as well as the interpeak latencies I-III, III-V, and I-V in the dyslexic subjects, although increased in comparison with normal subjects, did not reach the level of a significant difference (pwave C and the interpeak latencies of A-C elicited by verbal stimuli were found to be increased in the dyslexic group in comparison with the control group (p=0.0004 and p=0.045, respectively). In the subgroup consisting of 10 patients suffering from

  17. Craniofacial Pain: Brainstem Mechanisms

    Directory of Open Access Journals (Sweden)

    Barry J Sessle

    1996-01-01

    Full Text Available This article reviews recent research advances in animals that have identified critical neural elements in the brainstem receiving and transmitting craniofacial nociceptive inputs, as well as some of the mechanisms involved in the modulation and plasticity of nociceptive transmission. Nociceptive neurones in the trigeminal (V brainstem sensory nuclear complex can be classified as nociceptive-specific (NS or wide dynamic range (WDR. Some of these neurones respond exclusively to sensory inputs evoked by stimulation of facial skin or oral mucosa and have features suggesting that they are critical neural elements involved in the ability to localize an acute superficial pain and sense its intensity and duration. Many of the V brainstem nociceptive neurones, however, receive convergent inputs from afferents supplying deep craniofacial tissues (eg, dural vessel, muscle and skin or mucosa. These neurones are likely involved in deep pain, including headache, because few nociceptive neurones receive inputs exclusively from afferents supplying these tissues. These extensive convergent input patterns also appear to be important factors in pain spread and referral, and in central mechanisms underlying neuroplastic changes in V neuronal properties that may occur with injury and inflammation. For example, application of the small fibre excitant and inflammatory irritant mustard oil into the temporomandibular joint, masseter or tongue musculature induces a prolonged but reversible enhancement of responses to cutaneous and deep afferent inputs of most WDR and NS neurones. These effects may be accompanied by increased electromyographic activity reflexly induced in the masticatory muscles by mustard oil, and involve endogenous N-methyl-D-aspartate and opioid neurochemical mechanisms. Such peripherally induced modulation of brainstem nociceptive neuronal properties reflects the functional plasticity of the central V system, and may be involved in the development of

  18. The influence of cochlear traveling wave and neural adaptation on auditory brainstem responses

    DEFF Research Database (Denmark)

    Junius, D.; Dau, Torsten

    2005-01-01

    of the responses to the single components, as a function of stimulus level. In the first experiment, a single rising chirp was temporally and spectrally embedded in two steady-state tones. In the second experiment, the stimulus consisted of a continuous alternating train of chirps: each rising chirp was followed...... by the temporally reversed (falling) chirp. In both experiments, the transitions between stimulus components were continuous. For stimulation levels up to approximately 70 dB SPL, the responses to the embedded chirp corresponded to the responses to the single chirp. At high stimulus levels (80-100 dB SPL......), disparities occurred between the responses, reflecting a nonlinearity in the processing when neural activity is integrated across frequency. In the third experiment, the effect of within-train rate on wave-V response was investigated. The response to the chirp presented at a within-train rate of 95 Hz...

  19. Sensorineural hearing loss among cerebellopontine-angle tumor patients examined with pure tone audiometry and brainstem-evoked response audiometry

    Science.gov (United States)

    Rinindra, A. M.; Zizlavsky, S.; Bashiruddin, J.; Aman, R. A.; Wulani, V.; Bardosono, S.

    2017-08-01

    Tumor in the cerebellopontine angle (CPA) accurs for approximately 5-10% of all intracranial tumors, where unilateral hearing loss and tinnitus are the most frequent symptoms. This study aimed to collect data on sensorineural hearing loss in CPA tumor patients in Dr. Cipto Mangunkusumo Hospital (CMH) using pure tone audiometry and brainstem-evoked response audiometry (BERA). It also aimed to obtaine data on CPA-tumor imaging through magnetic resonance imaging (MRI). This was a descriptive, analytic, and cross-sectional study. The subjects of this study were gathered using a total sampling method from secondary data between July 2012 and November 2016. From 104 patients, 30 matched the inclusion criteria. The CPA-tumor patients in the ENT CMH outpatient clinic were mostly female, middle-aged patients (41-60 years) whose clinical presentation was mostly tinnitus and severe, asymmetric sensorineural hearing loss in 10 subjects. From 30 subjects, 29 showed ipsilaterally impaired BERA results, and 17 subjects showed contralaterally impaired BERA results. There were 24 subjects who with large-sized tumors and 19 subjects who had intracanal tumors that had spread until they were extracanal in 19 subjects.

  20. Piracetam-induced changes on the brainstem auditory response in anesthetized juvenile rhesus monkeys (Macaca mulatta). Report of two clinical cases.

    Science.gov (United States)

    Durand-Rivera, A; Gonzalez-Pina, R; Hernandez-Godinez, B; Ibanez-Contreras, A; Bueno-Nava, A; Alfaro-Rodriguez, A

    2012-10-01

    We describe two clinical cases and examine the effects of piracetam on the brainstem auditory response in infantile female rhesus monkeys (Macaca mulatta). We found that the interwave intervals show a greater reduction in a 3-year-old rhesus monkey compared to a 1-year-old rhesus monkey. In this report, we discuss the significance of these observations. © 2012 John Wiley & Sons A/S.

  1. Relation between derived-band auditory brainstem response latencies and behavioral frequency selectivity

    DEFF Research Database (Denmark)

    Strelcyk, Olaf; Christoforidis, Dimitrios; Dau, Torsten

    2009-01-01

    response times. For the same listeners, auditory-filter bandwidths at 2 kHz were estimated using a behavioral notched-noise masking paradigm. Generally, shorter derived-band latencies were observed for the HI than for the NH listeners. Only at low click sensation levels, prolonged latencies were obtained...

  2. Auditory brainstem response as a diagnostic tool for patients suffering from schizophrenia, attention deficit hyperactivity disorder, and bipolar disorder: protocol.

    Science.gov (United States)

    Wahlström, Viktor; Åhlander, Fredrik; Wynn, Rolf

    2015-02-12

    Psychiatric disorders, such as schizophrenia, attention deficit hyperactivity disorder (ADHD), and bipolar disorder, may sometimes be difficult to diagnose. There is a great need for a valid and reliable diagnostic tool to aid clinicians in arriving at the diagnoses in a timely and accurate manner. Prior studies have suggested that patients suffering from schizophrenia and ADHD may process certain sound stimuli in the brainstem in an unusual manner. When these patient groups have been examined with the electrophysiological method of brainstem audiometry, some studies have found illness-specific aberrations. Such aberrations may also exist for patients suffering from bipolar disorder. In this study, we will examine whether the method of brainstem audiometry can be used as a diagnostic tool for patients suffering from schizophrenia, ADHD, and bipolar disorder. The method includes three steps: (1) auditory stimulation with specific sound stimuli, (2) simultaneous measurement of brainstem activity, and (3) automated interpretation of the resulting brain stem audiograms with data-based signal analysis. We will compare three groups of 12 individuals with confirmed diagnoses of schizophrenia, ADHD, or bipolar disorder with 12 healthy subjects under blinded conditions for a total of 48 participants. The extent to which the method can be used to reach the correct diagnosis will be investigated. The project is now in a recruiting phase. When all patients and controls have been recruited and the measurements have been performed, the data will be analyzed according to a previously arranged algorithm. We expect the recruiting phase and measurements to be completed in early 2015, the analyses to be performed in mid-2015, and the results of the study to be published in early 2016. If the results support previous findings, this will lend strength to the idea that brainstem audiometry can offer objective diagnostic support for patients suffering from schizophrenia, ADHD, and

  3. Redundant and distinct functions of the ABA response loci ABA-INSENSITIVE(ABI)5 and ABRE-BINDING FACTOR (ABF)3.

    Science.gov (United States)

    Finkelstein, Ruth; Gampala, Srinivas S L; Lynch, Tim J; Thomas, Terry L; Rock, Christopher D

    2005-09-01

    Abscisic acid-responsive gene expression is regulated by numerous transcription factors, including a subgroup of basic leucine zipper factors that bind to the conserved cis-acting sequences known as ABA-responsive elements. Although one of these factors, ABA-insensitive 5 (ABI5), was identified genetically, the paucity of genetic data for the other family members has left it unclear whether they perform unique functions or act redundantly to ABI5 or each other. To test for potential redundancy with ABI5, we identified the family members with most similar effects and interactions in transient expression systems (ABF3 and ABF1), then characterized loss-of-function lines for those loci. The abf1 and abf3 monogenic mutant lines had at most minimal effects on germination or seed-specific gene expression, but the enhanced ABA- and stress-resistance of abf3 abi5 double mutants revealed redundant action of these genes in multiple stress responses of seeds and seedlings. Although ABI5, ABF3, and ABF1 have some overlapping effects, they appear to antagonistically regulate each other's expression at specific stages. Consequently, loss of any one factor may be partially compensated by increased expression of other family members.

  4. Processing Complex Sounds Passing through the Rostral Brainstem: The New Early Filter Model

    Science.gov (United States)

    Marsh, John E.; Campbell, Tom A.

    2016-01-01

    The rostral brainstem receives both “bottom-up” input from the ascending auditory system and “top-down” descending corticofugal connections. Speech information passing through the inferior colliculus of elderly listeners reflects the periodicity envelope of a speech syllable. This information arguably also reflects a composite of temporal-fine-structure (TFS) information from the higher frequency vowel harmonics of that repeated syllable. The amplitude of those higher frequency harmonics, bearing even higher frequency TFS information, correlates positively with the word recognition ability of elderly listeners under reverberatory conditions. Also relevant is that working memory capacity (WMC), which is subject to age-related decline, constrains the processing of sounds at the level of the brainstem. Turning to the effects of a visually presented sensory or memory load on auditory processes, there is a load-dependent reduction of that processing, as manifest in the auditory brainstem responses (ABR) evoked by to-be-ignored clicks. Wave V decreases in amplitude with increases in the visually presented memory load. A visually presented sensory load also produces a load-dependent reduction of a slightly different sort: The sensory load of visually presented information limits the disruptive effects of background sound upon working memory performance. A new early filter model is thus advanced whereby systems within the frontal lobe (affected by sensory or memory load) cholinergically influence top-down corticofugal connections. Those corticofugal connections constrain the processing of complex sounds such as speech at the level of the brainstem. Selective attention thereby limits the distracting effects of background sound entering the higher auditory system via the inferior colliculus. Processing TFS in the brainstem relates to perception of speech under adverse conditions. Attentional selectivity is crucial when the signal heard is degraded or masked: e

  5. A brainstem anosognosia of hemiparesis

    Directory of Open Access Journals (Sweden)

    Kazuo Abe

    2009-10-01

    Full Text Available A woman had anosognosia for hemiplegia as a manifestation of brainstem infarction. She had no mental or neuropsychological disturbances, and had involvement of the brainstem in the frontal/parietal-subcortical circuits to the right cerebral hemisphere. Brainstem lesions that disrupt frontal/parietal-subcortical areas may affect anosognosia for hemiplegia.

  6. Pediatric brainstem oligodendroglioma

    Directory of Open Access Journals (Sweden)

    Sandeep Mohindra

    2012-01-01

    Full Text Available The authors present the first report of pediatric brainstem oligodendroglioma, infiltrating midbrain, and medulla oblongata. The report details clinical features, radiological findings, and surgical steps. As this entity is exceedingly uncommon, the overall epidemiology, prognosis, and long-term outcome remain far from established.

  7. Aplicação da audiometria troncoencefálica na detecção de perdas auditivas retrococleares em trabalhadores de manutenção hospitalar expostos a ruído Auditory brainstem responses evaluation of retrocochlear disease in workers from a general hospital exposed to noise

    Directory of Open Access Journals (Sweden)

    Victor Luiz da Silveira

    2011-02-01

    Full Text Available O objetivo principal deste estudo seccional foi averiguar a presença de comprometimento auditivo retrococlear num grupo de trabalhadores de manutenção de um hospital de grande porte com histórico de exposição a ruído. Foram avaliados 31 trabalhadores de três setores da divisão de engenharia entre 25 e 60 anos e com exposição contínua a ruído entre 2 e 45 anos. O processo avaliativo contou com triagem audiométrica ocupacional e audiometria troncoencefálica (ATE. Foram detectadas anormalidades na ATE em sete pacientes (22,6%, caracterizadas por aumento de latências de ondas III (14,3% e V (28,6%; prolongamento dos interpicos I-III (71,4%, III-V (28,6% e I-V (85,7%. Das 35 orelhas com audição normal (três unilateralmente e 32 bilateralmente, quatro (11,4% apresentaram comprometimento retrococlear. A alta prevalência de comprometimento retrococlear no grupo induz supor que tal distúrbio seja mais frequente que o encontrado e esteja sendo subestimado na investigação diagnóstica desses trabalhadores. A ocorrência desses resultados sem a presença de alterações audiométricas sugere que a ATE seja mais sensível que a audiometria tonal na investigação de perda auditiva provocada por ruído, por isso sua utilização deva ser incentivada.The main purpose of this cross-seccional study was to investigate the presence of retrocochlear disease in a group of maintenance workers from a general hospital, who presents a history of noise exposure. Thirty one workers of three engineering sections with age range from 25 to 60 years and continuous noise exposure from 2 and 45 years, were examined. The evaluation included an audiometric occupational selection and auditory brainstem responses (ABR. ABR abnormalities were detected in seven patients (22.6% and it was found latency increase of waves III (14.3% and V (28.6%, and interpeak prolongation I-III (71.4%, III-V (28.6% and I-V (85.7%. Among 35 ears with normal audition right, left or

  8. ABR-based newborn hearing screening with MB11 BERAphone® using an optimized chirp for acoustical stimulation.

    Science.gov (United States)

    Cebulla, Mario; Shehata-Dieler, Wafaa

    2012-04-01

    At our center, the Maico MB11 BERAphone(®) device is used for newborn hearing screening based on Auditory Brainstem Responses (ABR). In 2006, an optimized chirp stimulus was implemented in the device to increase the reliability and quality of the screening method. In 2002, an automated response detection algorithm had been implemented. This study analyzes the screening results using the MB11 BERAphone(®) device with the implemented chirp stimulus and automated response detection method. The data presented were collected in the well-baby nursery as part of the newborn hearing screening program following a two stage screening protocol. To focus the study on the typical routine screening, data from at-risk babies were not included. Overall, data from 6866 babies (3604 males and 3262 females) screened from March 2006 to April 2011 were analyzed in this study. Out of the 6866 babies screened, 6607 passed bilaterally prior to hospital discharge (defined as 1st stage in this hearing screening program). Therefore, the pre-discharge pass rate of the hearing screening with the MB11 BERAphone(®) device was 96.2%. The resulting referral rate was 3.8%. The median test time per ear (excluding time for preparation and data reporting) was 28s with a range of 15-112s (5-95th percentile). The number of infants referred for 2nd stage, post-discharge re-screening was 259. Of this group, 71 passed bilaterally and 188 failed the re-screening in one or both ears. Therefore, including both the pre-discharge and post-discharge screening results, the bilateral pass rate was 97.3% and 2.7% were referred for diagnostic evaluation. Diagnostic testing was performed on all of the 188 infants who were referred. Results showed that 47 of these babies had hearing loss. This equates to a positive predictive value for a refer result of 25%. The observed prevalence of hearing impairment in our population was 0.684%. Diagnostic results for 141 of the referred newborns proved that they had normal

  9. The anaerobic baffled reactor (ABR): An appropriate technology for ...

    African Journals Online (AJOL)

    This project has studied the appropriateness of the ABR for on-site primary sanitation in low-income communities. The baffled design of the ABR ensures high solids retention resulting in high treatment rates, while the overall sludge production is characteristically low. Effluent COD values measured from a 3 000 l pilot ABR ...

  10. Effect of neonatal asphyxia on the impairment of the auditory pathway by recording auditory brainstem responses in newborn piglets: a new experimentation model to study the perinatal hypoxic-ischemic damage on the auditory system.

    Directory of Open Access Journals (Sweden)

    Francisco Jose Alvarez

    Full Text Available Hypoxia-ischemia (HI is a major perinatal problem that results in severe damage to the brain impairing the normal development of the auditory system. The purpose of the present study is to study the effect of perinatal asphyxia on the auditory pathway by recording auditory brain responses in a novel animal experimentation model in newborn piglets.Hypoxia-ischemia was induced to 1.3 day-old piglets by clamping 30 minutes both carotid arteries by vascular occluders and lowering the fraction of inspired oxygen. We compared the Auditory Brain Responses (ABRs of newborn piglets exposed to acute hypoxia/ischemia (n = 6 and a control group with no such exposure (n = 10. ABRs were recorded for both ears before the start of the experiment (baseline, after 30 minutes of HI injury, and every 30 minutes during 6 h after the HI injury.Auditory brain responses were altered during the hypoxic-ischemic insult but recovered 30-60 minutes later. Hypoxia/ischemia seemed to induce auditory functional damage by increasing I-V latencies and decreasing wave I, III and V amplitudes, although differences were not significant.The described experimental model of hypoxia-ischemia in newborn piglets may be useful for studying the effect of perinatal asphyxia on the impairment of the auditory pathway.

  11. Brainstem Tuberculoma in Pregnancy

    Directory of Open Access Journals (Sweden)

    Dana A. Muin

    2015-01-01

    Full Text Available We report a case of a Somali refugee who presented in the second trimester of her first pregnancy with a four-week history of gradual right-sided sensomotoric hemisyndrome including facial palsy and left-sided paresis of the oculomotorius nerve causing drooping of the left eyelid and double vision. Cranial magnetic resonance imaging revealed a solitary brainstem lesion. Upon detection of hilar lymphadenopathy on chest X-ray (CXR, the diagnosis of disseminated tuberculosis with involvement of the central nervous system was confirmed by PCR and treatment induced with rifampicin, isoniazid, pyrazinamide, and ethambutol. The patient had a steady neurological improvement and a favorable pregnancy outcome.

  12. Early postnatal virus inoculation into the scala media achieved extensive expression of exogenous green fluorescent protein in the inner ear and preserved auditory brainstem response thresholds.

    Science.gov (United States)

    Wang, Yunfeng; Sun, Yu; Chang, Qing; Ahmad, Shoeb; Zhou, Binfei; Kim, Yeunjung; Li, Huawei; Lin, Xi

    2013-01-01

    Gene transfer into the inner ear is a promising approach for treating sensorineural hearing loss. The special electrochemical environment of the scala media raises a formidable challenge for effective gene delivery at the same time as keeping normal cochlear function intact. The present study aimed to define a suitable strategy for preserving hearing after viral inoculation directly into the scala media performed at various postnatal developmental stages. We assessed transgene expression of green fluorescent protein (GFP) mediated by various types of adeno-associated virus (AAV) and lentivirus (LV) in the mouse cochlea. Auditory brainstem responses were measured 30 days after inoculation to assess effects on hearing. Patterns of GFP expression confirmed extensive exogenous gene expression in various types of cells lining the endolymphatic space. The use of different viral vectors and promoters resulted in specific cellular GFP expression patterns. AAV2/1 with cytomegalovirus promoter apparently gave the best results for GFP expression in the supporting cells. Histological examination showed normal cochlear morphology and no hair cell loss after either AAV or LV injections. We found that hearing thresholds were not significantly changed when the injections were performed in mice younger than postnatal day 5, regardless of the type of virus tested. Viral inoculation and expression in the inner ear for the restoration of hearing must not damage cochlear function. Using normal hearing mice as a model, we have achieved this necessary step, which is required for the treatment of many types of congenital deafness that require early intervention. Copyright © 2013 John Wiley & Sons, Ltd.

  13. MR findings of brainstem injury

    Energy Technology Data Exchange (ETDEWEB)

    Park, Man Soo; Hwang, Woo Cheol; Park, Choong Ki [Hallym University College of Medicine, Seoul (Korea, Republic of); Suh, Dae Chul [University of Ulsan College of Medicine, Seoul (Korea, Republic of); Kim, Sang Joon [Dankook University of College of Medicine, Cheonan (Korea, Republic of)

    1995-02-15

    To analyze the characteristics of traumatic brainstem injury by CT and MR. CT and MR studies of 10 patients with traumatic brainstem lesion in MR were retrospectively reviewed, particularly attended to location, signal intensity and associated lesions. CT failed to depict 8 of 10 brainstem lesions. All lesions were detected in MR images with T2-weighted images showing higher detection rate (n = 10) (100%) than T1-weighted images (n = 3) (30%) or CT (n = 2) (20%). The brainstem lesions located in the dorsolateral aspects of the rostral brainstem (mid brain and upper pons) in 7 (70%) cases, in ventral aspects of rostral brain in 2 (20%) cases and in median portion of pons in 1 (10%) case. Corpus callosal (n = 5), lobar white matter (n = 5) diffuse axonal injury, and 2 hemorrhagic lesions in basal ganglia were the associated findings. MR imaging is more helpful than CT in the detection of brainstem injury, especially T2 weighted images. Primary brainstem lesions were typically located in the dorsolateral aspect of rostral brainstem (midbrain and upper pons). Corpus callosum and white matter lesions were frequently associated.

  14. Identifying cochlear implant channels with poor electrode-neuron interface: electrically-evoked auditory brainstem responses measured with the partial tripolar configuration

    Science.gov (United States)

    Bierer, Julie Arenberg; Faulkner, Kathleen F.; Tremblay, Kelly L.

    2011-01-01

    Objectives The goal of this study was to compare cochlear implant behavioral measures and electrically-evoked auditory brainstem responses (EABRs) obtained with a spatially focused electrode configuration. It has been shown previously that channels with high thresholds, when measured with the tripolar configuration, exhibit relatively broad psychophysical tuning curves (Bierer and Faulkner, 2010). The elevated threshold and degraded spatial/spectral selectivity of such channels are consistent with a poor electrode-neuron interface, such as suboptimal electrode placement or reduced nerve survival. However, the psychophysical methods required to obtain these data are time intensive and may not be practical during a clinical mapping procedure, especially for young children. Here we have extended the previous investigation to determine if a physiological approach could provide a similar assessment of channel functionality. We hypothesized that, in accordance with the perceptual measures, higher EABR thresholds would correlate with steeper EABR amplitude growth functions, reflecting a degraded electrode-neuron interface. Design Data were collected from six cochlear implant listeners implanted with the HiRes 90k cochlear implant (Advanced Bionics). Single-channel thresholds and most comfortable listening levels were obtained for stimuli that varied in presumed electrical field size by using the partial tripolar configuration, for which a fraction of current (σ) from a center active electrode returns through two neighboring electrodes and the remainder through a distant indifferent electrode. EABRs were obtained in each subject for the two channels having the highest and lowest tripolar (σ=1 or 0.9) behavioral threshold. Evoked potentials were measured with both the monopolar (σ=0) and a more focused partial tripolar (σ ≥ 0.50) configuration. Results Consistent with previous studies, EABR thresholds were highly and positively correlated with behavioral thresholds

  15. Auditory-steady-state response reliability in the audiological diagnosis after neonatal hearing screening.

    Science.gov (United States)

    Núñez-Batalla, Faustino; Noriega-Iglesias, Sabel; Guntín-García, Maite; Carro-Fernández, Pilar; Llorente-Pendás, José Luis

    2016-01-01

    Conventional audiometry is the gold standard for quantifying and describing hearing loss. Alternative methods become necessary to assess subjects who are too young to respond reliably. Auditory evoked potentials constitute the most widely used method for determining hearing thresholds objectively; however, this stimulus is not frequency specific. The advent of the auditory steady-state response (ASSR) leads to more specific threshold determination. The current study describes and compares ASSR, auditory brainstem response (ABR) and conventional behavioural tone audiometry thresholds in a group of infants with various degrees of hearing loss. A comparison was made between ASSR, ABR and behavioural hearing thresholds in 35 infants detected in the neonatal hearing screening program. Mean difference scores (±SD) between ABR and high frequency ABR thresholds were 11.2 dB (±13) and 10.2 dB (±11). Pearson correlations between the ASSR and audiometry thresholds were 0.80 and 0.91 (500Hz); 0.84 and 0.82 (1000Hz); 0.85 and 0.84 (2000Hz); and 0.83 and 0.82 (4000Hz). The ASSR technique is a valuable extension of the clinical test battery for hearing-impaired children. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

  16. Challenge-driven attention: interacting frontal and brainstem systems

    Directory of Open Access Journals (Sweden)

    Rajeev D S Raizada

    2008-03-01

    Full Text Available The world is an unpredictable place, presenting challenges that fl uctuate from moment to moment. However, the neural systems for responding to such challenges are far from fully understood. Using fMRI, we studied an audiovisual task in which the trials' diffi culty and onset times varied unpredictably. Two regions were found to increase their activation for challenging trials, with their activities strongly correlated: right frontal cortex and the brainstem. The frontal area matched regions found in previous human studies of cognitive control, and activated in a graded manner with increasing task diffi culty. The brainstem responded only to the most diffi cult trials, showing a phasic activity pattern paralleling locus coeruleus recordings in monkeys. These results reveal a bridge between animal and human studies, and suggest interacting roles for the brainstem and right frontal cortex: the brainstem may signal that an attentional challenge is occurring, while right frontal cortex allocates cognitive resources in response.

  17. Alteration of glycine receptor immunoreactivity in the auditory brainstem of mice following three months of exposure to radiofrequency radiation at SAR 4.0 W/kg.

    Science.gov (United States)

    Maskey, Dhiraj; Kim, Hyung Gun; Suh, Myung-Whan; Roh, Gu Seob; Kim, Myeung Ju

    2014-08-01

    The increasing use of mobile communication has triggered an interest in its possible effects on the regulation of neurotransmitter signals. Due to the close proximity of mobile phones to hearing-related brain regions during usage, its use may lead to a decrease in the ability to segregate sounds, leading to serious auditory dysfunction caused by the prolonged exposure to radiofrequency (RF) radiation. The interplay among auditory processing, excitation and inhibitory molecule interactions plays a major role in auditory function. In particular, inhibitory molecules, such a glycine, are predominantly localized in the auditory brainstem. However, the effects of exposure to RF radiation on auditory function have not been reported to date. Thus, the aim of the present study was to investigate the effects of exposure to RF radiation on glycine receptor (GlyR) immunoreactivity (IR) in the auditory brainstem region at 835 MHz with a specific absorption rate of 4.0 W/kg for three months using free-floating immunohistochemistry. Compared with the sham control (SC) group, a significant loss of staining intensity of neuropils and cells in the different subdivisions of the auditory brainstem regions was observed in the mice exposed to RF radiation (E4 group). A decrease in the number of GlyR immunoreactive cells was also noted in the cochlear nuclear complex [anteroventral cochlear nucleus (AVCN), 31.09%; dorsal cochlear nucleus (DCN), 14.08%; posteroventral cochlear nucleus (PVCN), 32.79%] and the superior olivary complex (SOC) [lateral superior olivary nucleus (LSO), 36.85%; superior paraolivary nucleus (SPN), 24.33%, medial superior olivary nucleus (MSO), 23.23%; medial nucleus of the trapezoid body (MNTB), 10.15%] of the mice in the E4 group. Auditory brainstem response (ABR) analysis also revealed a significant threshold elevation of in the exposed (E4) group, which may be associated with auditory dysfunction. The present study suggests that the auditory brainstem region

  18. Analysis of a multi-server queueing model of ABR

    NARCIS (Netherlands)

    R. Núñez Queija (Rudesindo); O.J. Boxma (Onno)

    1996-01-01

    textabstractIn this paper we present a queueing model for the performance a-na-ly-sis of ABR traffic in ATM networks. We consider a multi-channel service station with two types of customers, the first having preemptive priority over the second. The arrivals occur according to two independent Poisson

  19. Further characterization of the ABR gene in medulloblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Wright-White, E.C.; Haken, M.S. von; McDonald J.D. [Univ. of Chicago, IL (United States)] [and others

    1994-09-01

    Although brain tumors are the most common type of solid cancer in children, little is known about their etiology at the molecular genetic level. Using a panel of 20 chromosome 17p markers, we have previously determined that loss of distal chromosome 17p DNA sequences occurs in 14 of 35 specimens (40%) of medulloblastoma, one of the most common pediatric intracranial neoplasms. Analysis of these same tumors using a PCR-denaturing gradient gel electrophoresis technique has shown only two p53 gene mutations. These results suggest that a tumor suppressor gene in addition to p53 may be located on distal chromosome 17p. Consensus deletion mapping of our specimens suggests that the smallest site of chromosomal loss in defined distally by marker 144-D6, the most telomeric probe as yet identified on chromosome 17p, and proximally by the ABR marker, a BCR homologous gene containing two highly polymorphic VNTR regions. We have used fluorescence in situ hybridization and pulsed-field gel electrophoresis to determine that the ABR gene lies transcriptionally oriented 5{prime} to 3{prime} at a distance of 240 kb from marker 144-D6. We have also constructed a cosmid contig map spanning 120 kb of this region. Using one of these cosmids as a probe, we have detected breakpoints in three of the tumor specimens that lie between the two VNTR regions within the ABR gene. We have subsequently designed PCR primers to cover the breakpoint region which include the ABR exons which have the strongest homology to the BCR gene (Mbcr region), and are screening our tumor specimens for mutations. These results suggest that loss of ABR gene sequences may be involved in the etiology of medulloblastoma.

  20. A Comparison of Two Objective Measures of Binaural Processing: The Interaural Phase Modulation Following Response and the Binaural Interaction Component.

    Science.gov (United States)

    Haywood, Nicholas R; Undurraga, Jaime A; Marquardt, Torsten; McAlpine, David

    2015-12-30

    There has been continued interest in clinical objective measures of binaural processing. One commonly proposed measure is the binaural interaction component (BIC), which is obtained typically by recording auditory brainstem responses (ABRs)-the BIC reflects the difference between the binaural ABR and the sum of the monaural ABRs (i.e., binaural - (left + right)). We have recently developed an alternative, direct measure of sensitivity to interaural time differences, namely, a following response to modulations in interaural phase difference (the interaural phase modulation following response; IPM-FR). To obtain this measure, an ongoing diotically amplitude-modulated signal is presented, and the interaural phase difference of the carrier is switched periodically at minima in the modulation cycle. Such periodic modulations to interaural phase difference can evoke a steady state following response. BIC and IPM-FR measurements were compared from 10 normal-hearing subjects using a 16-channel electroencephalographic system. Both ABRs and IPM-FRs were observed most clearly from similar electrode locations-differential recordings taken from electrodes near the ear (e.g., mastoid) in reference to a vertex electrode (Cz). Although all subjects displayed clear ABRs, the BIC was not reliably observed. In contrast, the IPM-FR typically elicited a robust and significant response. In addition, the IPM-FR measure required a considerably shorter recording session. As the IPM-FR magnitude varied with interaural phase difference modulation depth, it could potentially serve as a correlate of perceptual salience. Overall, the IPM-FR appears a more suitable clinical measure than the BIC. © The Author(s) 2015.

  1. Identification, occurrence, and validation of DRE and ABRE Cis-regulatory motifs in the promoter regions of genes of Arabidopsis thaliana.

    Science.gov (United States)

    Mishra, Sonal; Shukla, Aparna; Upadhyay, Swati; Sanchita; Sharma, Pooja; Singh, Seema; Phukan, Ujjal J; Meena, Abha; Khan, Feroz; Tripathi, Vineeta; Shukla, Rakesh Kumar; Shrama, Ashok

    2014-04-01

    Plants posses a complex co-regulatory network which helps them to elicit a response under diverse adverse conditions. We used an in silico approach to identify the genes with both DRE and ABRE motifs in their promoter regions in Arabidopsis thaliana. Our results showed that Arabidopsis contains a set of 2,052 genes with ABRE and DRE motifs in their promoter regions. Approximately 72% or more of the total predicted 2,052 genes had a gap distance of less than 400 bp between DRE and ABRE motifs. For positional orientation of the DRE and ABRE motifs, we found that the DR form (one in direct and the other one in reverse orientation) was more prevalent than other forms. These predicted 2,052 genes include 155 transcription factors. Using microarray data from The Arabidopsis Information Resource (TAIR) database, we present 44 transcription factors out of 155 which are upregulated by more than twofold in response to osmotic stress and ABA treatment. Fifty-one transcripts from the one predicted above were validated using semiquantitative expression analysis to support the microarray data in TAIR. Taken together, we report a set of genes containing both DRE and ABRE motifs in their promoter regions in A. thaliana, which can be useful to understand the role of ABA under osmotic stress condition. © 2013 Institute of Botany, Chinese Academy of Sciences.

  2. Lyme disease of the brainstem

    Energy Technology Data Exchange (ETDEWEB)

    Kalina, Peter [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Decker, Andrew [Northern Westchester Hospital Center, Department of Neurology, Mt. Kisco, NY (United States); Kornel, Ezriel [Northern Westchester Hospital Center, Division of Neurosurgery, Mt. Kisco, NY (United States); Halperin, John J. [North Shore University Hospital, Department of Neurology, Manhasset, NY (United States)

    2005-12-01

    Lyme disease is a multisystem infectious disease caused by the tick-borne spirochete, Borrelia burgdorferi. Central nervous system (CNS) involvement typically causes local inflammation, most commonly meningitis, but rarely parenchymal brain involvement. We describe a patient who presented with clinical findings suggesting a brainstem process. Magnetic resonance imaging (MRI) and positron emission tomography (PET) suggested a brainstem neoplasm. Prior to biopsy, laboratory evaluation led to the diagnosis of Lyme disease. Clinical and imaging abnormalities improved markedly following antimicrobial therapy. We describe Lyme disease involvement of the cerebellar peduncles with hypermetabolism on PET. Although MRI is the primary imaging modality for most suspected CNS pathology, the practical applications of PET continue to expand. (orig.)

  3. Lyme disease of the brainstem

    International Nuclear Information System (INIS)

    Kalina, Peter; Decker, Andrew; Kornel, Ezriel; Halperin, John J.

    2005-01-01

    Lyme disease is a multisystem infectious disease caused by the tick-borne spirochete, Borrelia burgdorferi. Central nervous system (CNS) involvement typically causes local inflammation, most commonly meningitis, but rarely parenchymal brain involvement. We describe a patient who presented with clinical findings suggesting a brainstem process. Magnetic resonance imaging (MRI) and positron emission tomography (PET) suggested a brainstem neoplasm. Prior to biopsy, laboratory evaluation led to the diagnosis of Lyme disease. Clinical and imaging abnormalities improved markedly following antimicrobial therapy. We describe Lyme disease involvement of the cerebellar peduncles with hypermetabolism on PET. Although MRI is the primary imaging modality for most suspected CNS pathology, the practical applications of PET continue to expand. (orig.)

  4. Contribuição do potencial evocado auditivo em pacientes com vertigem Results of brainstem evoked response in patients with vestibular complaints

    Directory of Open Access Journals (Sweden)

    Gisiane Munaro

    2010-06-01

    Full Text Available A avaliação otoneurológica consiste em exames para investigação de patologias auditivas e vestibulares, incluindo o potencial evocado de tronco encefálico e a vectoeletronistagmografia. OBJETIVO: Descrever os resultados da avaliação otoneurológica em pacientes com queixas vestibulococleares, normo-ouvintes e com perda auditiva, comparados a grupo-controle. MATERIAL E MÉTODOS: Estudo transversal, retrospectivo, observacional, realizado com 56 pacientes vertiginosos avaliados por audiometria, vectoeletronistagmografia e potencial evocado auditivo de tronco encefálico, divididos em grupo A, 31 pacientes normo-ouvintes, e grupo B, 25 pacientes com perda auditiva, comparados ao grupo-controle constituído por dez voluntários normo-ouvintes assintomáticos. RESULTADOS: Os pacientes dos grupos A e B apresentaram aumento em monobloco das latências absolutas das ondas I, III e V estatisticamente significante, quando comparados ao grupo-controle, embora com valores dentro da normalidade. A ausência da onda I a 80 dBNA foi um achado comum para ambos os grupos e ocorreu em quatro (12,9% sujeitos bilateralmente e em três (9,6% unilateralmente no grupo A e em oito (32% pacientes no grupo B bilateralmente. Nos dois casos em que a vectoeletronistagmografia acusou alteração vestibular central não ocorreram alterações nos parâmetros dos potenciais evocados. CONCLUSÃO: Os pacientes com vertigem, normo-ouvintes e com perda auditiva, apresentaram latências absolutas aumentadas quando comparados a grupo-controleOtoneurological evaluations are based on tests which investigate auditory and vestibular disorders, including brainstem evoked auditory potentials and vecto-electronystagmography. AIM: to describe the results from the otoneurological assessment of patients with vestibulocochlear complaints, normal hearing individuals and patients with hearing loss, and we will compare them to a control group. MATERIALS AND METHODS: Cross

  5. Systematic Morphometry of Catecholamine Nuclei in the Brainstem.

    Science.gov (United States)

    Bucci, Domenico; Busceti, Carla L; Calierno, Maria T; Di Pietro, Paola; Madonna, Michele; Biagioni, Francesca; Ryskalin, Larisa; Limanaqi, Fiona; Nicoletti, Ferdinando; Fornai, Francesco

    2017-01-01

    Catecholamine nuclei within the brainstem reticular formation (RF) play a pivotal role in a variety of brain functions. However, a systematic characterization of these nuclei in the very same experimental conditions is missing so far. Tyrosine hydroxylase (TH) immune-positive cells of the brainstem correspond to dopamine (DA)-, norepinephrine (NE)-, and epinephrine (E)-containing cells. Here, we report a systematic count of TH-positive neurons in the RF of the mouse brainstem by using stereological morphometry. All these nuclei were analyzed for anatomical localization, rostro-caudal extension, volume, neuron number, neuron density, and mean neuronal area for each nucleus. The present data apart from inherent informative value wish to represent a reference for neuronal mapping in those studies investigating the functional anatomy of the brainstem RF. These include: the sleep-wake cycle, movement control, muscle tone modulation, mood control, novelty orienting stimuli, attention, archaic responses to internal and external stressful stimuli, anxiety, breathing, blood pressure, and innumerable activities modulated by the archaic iso-dendritic hard core of the brainstem RF. Most TH-immune-positive cells fill the lateral part of the RF, which indeed possesses a high catecholamine content. A few nuclei are medial, although conventional nosography considers all these nuclei as part of the lateral column of the RF. Despite the key role of these nuclei in psychiatric and neurological disorders, only a few of them aspired a great attention in biomedical investigation, while most of them remain largely obscure although intense research is currently in progress. A simultaneous description of all these nuclei is not simply key to comprehend the variety of brainstem catecholamine reticular neurons, but probably represents an intrinsically key base for understanding brain physiology and physiopathology.

  6. Systematic Morphometry of Catecholamine Nuclei in the Brainstem

    Directory of Open Access Journals (Sweden)

    Domenico Bucci

    2017-11-01

    Full Text Available Catecholamine nuclei within the brainstem reticular formation (RF play a pivotal role in a variety of brain functions. However, a systematic characterization of these nuclei in the very same experimental conditions is missing so far. Tyrosine hydroxylase (TH immune-positive cells of the brainstem correspond to dopamine (DA-, norepinephrine (NE-, and epinephrine (E-containing cells. Here, we report a systematic count of TH-positive neurons in the RF of the mouse brainstem by using stereological morphometry. All these nuclei were analyzed for anatomical localization, rostro-caudal extension, volume, neuron number, neuron density, and mean neuronal area for each nucleus. The present data apart from inherent informative value wish to represent a reference for neuronal mapping in those studies investigating the functional anatomy of the brainstem RF. These include: the sleep-wake cycle, movement control, muscle tone modulation, mood control, novelty orienting stimuli, attention, archaic responses to internal and external stressful stimuli, anxiety, breathing, blood pressure, and innumerable activities modulated by the archaic iso-dendritic hard core of the brainstem RF. Most TH-immune-positive cells fill the lateral part of the RF, which indeed possesses a high catecholamine content. A few nuclei are medial, although conventional nosography considers all these nuclei as part of the lateral column of the RF. Despite the key role of these nuclei in psychiatric and neurological disorders, only a few of them aspired a great attention in biomedical investigation, while most of them remain largely obscure although intense research is currently in progress. A simultaneous description of all these nuclei is not simply key to comprehend the variety of brainstem catecholamine reticular neurons, but probably represents an intrinsically key base for understanding brain physiology and physiopathology.

  7. SU-B-213-06: Development of ABR Examination Questions

    International Nuclear Information System (INIS)

    Allison, J.

    2015-01-01

    The North American medical physics community validates the education received by medical physicists and the clinical qualifications for medical physicists through accreditation of educational programs and certification of medical physicists. Medical physics educational programs (graduate education and residency education) are accredited by the Commission on Accreditation of Medical Physics Education Programs (CAMPEP), whereas medical physicists are certified by several organizations, the most familiar of which is the American Board of Radiology (ABR). In order for an educational program to become accredited or a medical physicist to become certified, the applicant must meet certain specified standards set by the appropriate organization. In this Symposium, representatives from both CAMPEP and the ABR will describe the process by which standards are established as well as the process by which qualifications of candidates for accreditation or certification are shown to be compliant with these standards. The Symposium will conclude with a panel discussion. Learning Objectives: Recognize the difference between accreditation of an educational program and certification of an individual Identify the two organizations primarily responsible for these tasks Describe the development of educational standards Describe the process by which examination questions are developed GS is Executive Secretary of CAMPEP

  8. SU-B-213-05: Development of ABR Certification Standards

    International Nuclear Information System (INIS)

    Seibert, J.

    2015-01-01

    The North American medical physics community validates the education received by medical physicists and the clinical qualifications for medical physicists through accreditation of educational programs and certification of medical physicists. Medical physics educational programs (graduate education and residency education) are accredited by the Commission on Accreditation of Medical Physics Education Programs (CAMPEP), whereas medical physicists are certified by several organizations, the most familiar of which is the American Board of Radiology (ABR). In order for an educational program to become accredited or a medical physicist to become certified, the applicant must meet certain specified standards set by the appropriate organization. In this Symposium, representatives from both CAMPEP and the ABR will describe the process by which standards are established as well as the process by which qualifications of candidates for accreditation or certification are shown to be compliant with these standards. The Symposium will conclude with a panel discussion. Learning Objectives: Recognize the difference between accreditation of an educational program and certification of an individual Identify the two organizations primarily responsible for these tasks Describe the development of educational standards Describe the process by which examination questions are developed GS is Executive Secretary of CAMPEP

  9. ABR Core examination preparation: results of a survey of fourth-year radiology residents who took the 2013 examination.

    Science.gov (United States)

    Shetty, Anup S; Grajo, Joseph R; Decker, Summer; Heitkamp, Darel E; DeStigter, Kristen K; Mezwa, Duane G; Deitte, Lori

    2015-01-01

    A survey was administered to fourth-year radiology residents after receiving their results from the first American Board of Radiology (ABR) Core examination in 2013. The purpose was to gather information regarding resources and study strategies to share with program directors and future resident classes. An online survey was distributed to examinees nationwide. The survey included free-response and multiple choice questions that covered examination results, perceived value of enumerated study resources, case-based and didactic teaching conferences, board reviews, study materials for noninterpretive skills, multidisciplinary conference attendance, and free-form comments. Two hundred sixty-six of 1186 residents who took the Core examination responded to the survey. Some resources demonstrated a significant difference in perceived value between residents who passed the examination and residents who failed, including internal board reviews (1.10, P multiple choice questions, audience response, and integration of clinical physics and patient safety topics compared to residents who failed. Radiology residents and residency programs have adapted their preparations for the ABR Core examination in a variety of ways. Certain practices and study tools, including daily conferences and internal board reviews, had greater perceived value by residents who passed the examination than by residents who failed. This survey provides insights that can be used to assess and modify current preparation strategies for the ABR Core examination. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

  10. Brainstem pathology in spasmodic dysphonia

    Science.gov (United States)

    Simonyan, Kristina; Ludlow, Christy L.; Vortmeyer, Alexander O.

    2009-01-01

    Spasmodic dysphonia (SD) is a primary focal dystonia of unknown pathophysiology, characterized by involuntary spasms in the laryngeal muscles during speech production. We examined two rare cases of postmortem brainstem tissue from SD patients compared to four controls. In SD patients, small clusters of inflammation were found in the reticular formation surrounding solitary tract, spinal trigeminal and ambigual nuclei, inferior olive and pyramids. Mild neuronal degeneration and depigmentation were observed in the substantia nigra and locus coeruleus. No abnormal protein accumulations and no demyelination or axonal degeneration were found. These neuropathological findings may provide insights into the pathophysiology of SD. PMID:19795469

  11. Surgical management of spontaneous hypertensive brainstem hemorrhage

    Directory of Open Access Journals (Sweden)

    Bal Krishna Shrestha

    2015-09-01

    Full Text Available Spontaneous hypertensive brainstem hemorrhage is the spontaneous brainstem hemorrhage associated with long term hypertension but not having definite focal or objective lesion. It is a catastrophic event which has a poor prognosis and usually managed conservatively. It is not uncommon, especially in eastern Asian populations, accounting approximately for 10% of the intracerebral hemorrhage. Before the advent of computed tomography, the diagnosis of brainstem hemorrhage was usually based on the clinical picture or by autopsy and believed to be untreatable via surgery. The introduction of computed tomography permitted to categorize the subtypes of brainstem hemorrhage with more predicted outcome. Continuous ongoing developments in the stereotactic surgery and microsurgery have added more specific surgical management in these patients. However, whether to manage conservatively or promptly with surgical evacuation of hematoma is still a controversy. Studies have shown that an accurate prognostic assessment based on clinical and radiological features on admission is critical for establishing a reasonable therapeutic approach. Some authors have advocate conservative management, whereas others have suggested the efficacy of surgical treatment in brainstem hemorrhage. With the widening knowledge in microsurgical techniques as well as neuroimaging technology, there seems to have more optimistic hope of surgical management of spontaneous hypertensive brainstem hemorrhage for better prognosis. Here we present five cases of severe spontaneous hypertensive brainstem hemorrhage patients who had undergone surgery; and explore the possibilities of surgical management in patients with the spontaneous hypertensive brainstem hemorrhage.

  12. Auditory brainstem activity and development evoked by apical versus basal cochlear implant electrode stimulation in children.

    Science.gov (United States)

    Gordon, K A; Papsin, B C; Harrison, R V

    2007-08-01

    The role of apical versus basal cochlear implant electrode stimulation on central auditory development was examined. We hypothesized that, in children with early onset deafness, auditory development evoked by basal electrode stimulation would differ from that evoked more apically. Responses of the auditory nerve and brainstem, evoked by an apical and a basal implant electrode, were measured over the first year of cochlear implant use in 50 children with early onset severe to profound deafness who used hearing aids prior to implantation. Responses at initial stimulation were of larger amplitude and shorter latency when evoked by the apical electrode. No significant effects of residual hearing or age were found on initial response amplitudes or latencies. With implant use, responses evoked by both electrodes showed decreases in wave and interwave latencies reflecting decreased neural conduction time through the brainstem. Apical versus basal differences persisted with implant experience with one exception; eIII-eV interlatency differences decreased with implant use. Acute stimulation shows prolongation of basally versus apically evoked auditory nerve and brainstem responses in children with severe to profound deafness. Interwave latencies reflecting neural conduction along the caudal and rostral portions of the brainstem decreased over the first year of implant use. Differences in neural conduction times evoked by apical versus basal electrode stimulation persisted in the caudal but not rostral brainstem. Activity-dependent changes of the auditory brainstem occur in response to both apical and basal cochlear implant electrode stimulation.

  13. Analysis of a multi-server queueing model of ABR

    Directory of Open Access Journals (Sweden)

    R. Núñez-Queija

    1998-01-01

    Full Text Available In this paper we present a queueing model for the performance analysis of Available Bit Rate (ABR traffic in Asynchronous Transfer Mode (ATM networks. We consider a multi-channel service station with two types of customers, denoted by high priority and low priority customers. In principle, high priority customers have preemptive priority over low priority customers, except on a fixed number of channels that are reserved for low priority traffic. The arrivals occur according to two independent Poisson processes, and service times are assumed to be exponentially distributed. Each high priority customer requires a single server, whereas low priority customers are served in processor sharing fashion. We derive the joint distribution of the numbers of customers (of both types in the system in steady state. Numerical results illustrate the effect of high priority traffic on the service performance of low priority traffic.

  14. Imaging of adult brainstem gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Purohit, Bela, E-mail: purohitbela@yahoo.co.in; Kamli, Ali A.; Kollias, Spyros S.

    2015-04-15

    Highlights: •BSG are classified on MRI into diffuse low-grade, malignant, focal tectal and exophytic subtypes. •Their prognosis and treatment is variable and is almost similar to adult supratentorial gliomas. •This article illustrates the imaging of adult BSGs on MRI and FET-PET. •We also describe prognostic factors and the treatment options of these tumours. -- Abstract: Brainstem gliomas (BSGs) are uncommon in adults accounting for about 2% of all intracranial neoplasms. They are often phenotypically low-grade as compared to their more common paediatric counterparts. Since brainstem biopsies are rarely performed, these tumours are commonly classified according to their MR imaging characteristics into 4 subgroups: (a) diffuse intrinsic low-grade gliomas, (b) enhancing malignant gliomas, (c) focal tectal gliomas and (d) exophytic gliomas/other subtypes. The prognosis and treatment is variable for the different types and is almost similar to adult supratentorial gliomas. Radiotherapy (RT) with adjuvant chemotherapy is the standard treatment of diffuse low-grade and malignant BSGs, whereas, surgical resection is limited to the exophytic subtypes. Review of previous literature shows that the detailed imaging of adult BSGs has not received significant attention. This review illustrates in detail the imaging features of adult BSGs using conventional and advanced MR techniques like diffusion weighted imaging (DWI), diffusion tensor imaging (DTI), MR perfusion weighted imaging (PWI), MR spectroscopy (MRS), as well as {sup 18}F-fluoro-ethyl-tyrosine positron emission tomography ({sup 18}F-FET/PET). We have discussed the pertinent differences between childhood and adult BSGs, imaging mimics, prognostic factors and briefly reviewed the treatment options of these tumours.

  15. Assessment of Startup Fuel Options for the GNEP Advanced Burner Reactor (ABR)

    Energy Technology Data Exchange (ETDEWEB)

    Jon Carmack (062056); Kemal O. Pasamehmetoglu (103171); David Alberstein

    2008-02-01

    The Global Nuclear Energy Program (GNEP) includes a program element for the development and construction of an advanced sodium cooled fast reactor to demonstrate the burning (transmutation) of significant quantities of minor actinides obtained from a separations process and fabricated into a transuranic bearing fuel assembly. To demonstrate and qualify transuranic (TRU) fuel in a fast reactor, an Advanced Burner Reactor (ABR) prototype is needed. The ABR would necessarily be started up using conventional metal alloy or oxide (U or U, Pu) fuel. Startup fuel is needed for the ABR for the first 2 to 4 core loads of fuel in the ABR. Following start up, a series of advanced TRU bearing fuel assemblies will be irradiated in qualification lead test assemblies in the ABR. There are multiple options for this startup fuel. This report provides a description of the possible startup fuel options as well as possible fabrication alternatives available to the program in the current domestic and international facilities and infrastructure.

  16. Delayed neuronal cell death in brainstem after transient brainstem ischemia in gerbils

    Directory of Open Access Journals (Sweden)

    Hakuba Nobuhiro

    2010-09-01

    Full Text Available Abstract Background Because of the lack of reproducible brainstem ischemia models in rodents, the temporal profile of ischemic lesions in the brainstem after transient brainstem ischemia has not been evaluated intensively. Previously, we produced a reproducible brainstem ischemia model of Mongolian gerbils. Here, we showed the temporal profile of ischemic lesions after transient brainstem ischemia. Results Brainstem ischemia was produced by occlusion of the bilateral vertebral arteries just before their entry into the transverse foramina of the cervical vertebrae of Mongolian gerbils. Animals were subjected to brainstem ischemia for 15 min, and then reperfused for 0 d (just after ischemia, 1 d, 3 d and 7 d (n = 4 in each group. Sham-operated animals (n = 4 were used as control. After deep anesthesia, the gerbils were perfused with fixative for immunohistochemical investigation. Ischemic lesions were detected by immunostaining for microtubule-associated protein 2 (MAP2. Just after 15-min brainstem ischemia, ischemic lesions were detected in the lateral vestibular nucleus and the ventral part of the spinal trigeminal nucleus, and these ischemic lesions disappeared one day after reperfusion in all animals examined. However, 3 days and 7 days after reperfusion, ischemic lesions appeared again and clusters of ionized calcium-binding adapter molecule-1(IBA-1-positive cells were detected in the same areas in all animals. Conclusion These results suggest that delayed neuronal cell death took place in the brainstem after transient brainstem ischemia in gerbils.

  17. Correlation between auditory brainstem recordings and morphology as seen through the scanning electron microscope

    International Nuclear Information System (INIS)

    Hultcrantz, M.

    1988-01-01

    Pregnant CBA/CBA mice were exposed to 0.5, 1 and 2 Grey (Gy), (1 Gy = 100 rad) in single doses with whole body gamma-irradiation on the 12th, 13th and 16th gestational days, respectively. The animals were tested at an age of one month for vestibular and cochlear function. Thereafter the inner ears were analyzed with scanning electron microscopy. A morphological analysis with cytocochleograms was performed. Morphological changes in the vestibular part showed gross malformations in the cristae ampullares. Hair cells of type I seemed to be more severely changed than hair cells type II. The macula utriculi also showed malformations of the otoconia. All these changes were more pronounced when the irradiation was given early during pregnancy and with the highest doses used, except the otoconia which were more injured when irradiated day 16 of gestation. No disturbances of the equilibrium reflexes were noted. In the cochlea a dose-dependent, time-related damage pattern was demonstrated with pathological changes of outer (OHC) and inner (IHC) hair cells. When tested electrophysiologically for auditory function with auditory brainstem recordings (ABR), elevated thresholds were revealed different in shape depending on when during pregnancy irradiation took place. A good correlation existed between the morphological changes as seen in the cytocochleograms and the functional changes documented with the ABR

  18. Correlation between auditory brainstem recordings and morphology as seen through the scanning electron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Hultcrantz, M.

    1988-09-01

    Pregnant CBA/CBA mice were exposed to 0.5, 1 and 2 Grey (Gy), (1 Gy = 100 rad) in single doses with whole body gamma-irradiation on the 12th, 13th and 16th gestational days, respectively. The animals were tested at an age of one month for vestibular and cochlear function. Thereafter the inner ears were analyzed with scanning electron microscopy. A morphological analysis with cytocochleograms was performed. Morphological changes in the vestibular part showed gross malformations in the cristae ampullares. Hair cells of type I seemed to be more severely changed than hair cells type II. The macula utriculi also showed malformations of the otoconia. All these changes were more pronounced when the irradiation was given early during pregnancy and with the highest doses used, except the otoconia which were more injured when irradiated day 16 of gestation. No disturbances of the equilibrium reflexes were noted. In the cochlea a dose-dependent, time-related damage pattern was demonstrated with pathological changes of outer (OHC) and inner (IHC) hair cells. When tested electrophysiologically for auditory function with auditory brainstem recordings (ABR), elevated thresholds were revealed different in shape depending on when during pregnancy irradiation took place. A good correlation existed between the morphological changes as seen in the cytocochleograms and the functional changes documented with the ABR.

  19. Detection of brainstem involvemetn in multiple sclerosis

    International Nuclear Information System (INIS)

    Martinelli, V.; Comi, G.; Filippi, M.; Sora, M.G.N.; Magnani, G.; Locatelli, T.; Visciani, A.; Scotti, G.; Canal, N.

    1989-01-01

    The Gradient Refocusing Technique, which seppresses the influence of cerebrospinal fluis (GSF) and vascular motion artifact on MRI sensitivity, is applied combined with Brainstem Auditory Evoked Potentials (BAEPs) and median Somatosensory Evoked Potentials (SEPs) in the evaluation of the brainstem in 30 MS patients with clinical signs of involvement of this structure in order to reevaluate the sensitivity of these techniques. (Author). 2 refs.; 1 tab

  20. Impairments in musical abilities reflected in the auditory brainstem: evidence from congenital amusia.

    Science.gov (United States)

    Lehmann, Alexandre; Skoe, Erika; Moreau, Patricia; Peretz, Isabelle; Kraus, Nina

    2015-07-01

    Congenital amusia is a neurogenetic condition, characterized by a deficit in music perception and production, not explained by hearing loss, brain damage or lack of exposure to music. Despite inferior musical performance, amusics exhibit normal auditory cortical responses, with abnormal neural correlates suggested to lie beyond auditory cortices. Here we show, using auditory brainstem responses to complex sounds in humans, that fine-grained automatic processing of sounds is impoverished in amusia. Compared with matched non-musician controls, spectral amplitude was decreased in amusics for higher harmonic components of the auditory brainstem response. We also found a delayed response to the early transient aspects of the auditory stimulus in amusics. Neural measures of spectral amplitude and response timing correlated with participants' behavioral assessments of music processing. We demonstrate, for the first time, that amusia affects how complex acoustic signals are processed in the auditory brainstem. This neural signature of amusia mirrors what is observed in musicians, such that the aspects of the auditory brainstem responses that are enhanced in musicians are degraded in amusics. By showing that gradients of music abilities are reflected in the auditory brainstem, our findings have implications not only for current models of amusia but also for auditory functioning in general. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  1. Dyslexia risk gene relates to representation of sound in the auditory brainstem.

    Science.gov (United States)

    Neef, Nicole E; Müller, Bent; Liebig, Johanna; Schaadt, Gesa; Grigutsch, Maren; Gunter, Thomas C; Wilcke, Arndt; Kirsten, Holger; Skeide, Michael A; Kraft, Indra; Kraus, Nina; Emmrich, Frank; Brauer, Jens; Boltze, Johannes; Friederici, Angela D

    2017-04-01

    Dyslexia is a reading disorder with strong associations with KIAA0319 and DCDC2. Both genes play a functional role in spike time precision of neurons. Strikingly, poor readers show an imprecise encoding of fast transients of speech in the auditory brainstem. Whether dyslexia risk genes are related to the quality of sound encoding in the auditory brainstem remains to be investigated. Here, we quantified the response consistency of speech-evoked brainstem responses to the acoustically presented syllable [da] in 159 genotyped, literate and preliterate children. When controlling for age, sex, familial risk and intelligence, partial correlation analyses associated a higher dyslexia risk loading with KIAA0319 with noisier responses. In contrast, a higher risk loading with DCDC2 was associated with a trend towards more stable responses. These results suggest that unstable representation of sound, and thus, reduced neural discrimination ability of stop consonants, occurred in genotypes carrying a higher amount of KIAA0319 risk alleles. Current data provide the first evidence that the dyslexia-associated gene KIAA0319 can alter brainstem responses and impair phoneme processing in the auditory brainstem. This brain-gene relationship provides insight into the complex relationships between phenotype and genotype thereby improving the understanding of the dyslexia-inherent complex multifactorial condition. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. WE-D-213-01: Preparing for Part 1 of the ABR Diagnostic Physics Exam

    International Nuclear Information System (INIS)

    Simiele, S.

    2015-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  3. WE-D-213-00: Preparing for the ABR Diagnostic and Nuclear Medicine Physics Exams

    International Nuclear Information System (INIS)

    2015-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  4. MO-F-204-03: Preparing for Part 3 of the ABR Diagnostic Physics Exam

    International Nuclear Information System (INIS)

    Zambelli, J.

    2016-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  5. WE-D-213-02: Preparing for Part 2 of the ABR Diagnostic Physics Exam

    International Nuclear Information System (INIS)

    Zambelli, J.

    2015-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  6. WE-D-213-00: Preparing for the ABR Diagnostic and Nuclear Medicine Physics Exams

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  7. WE-D-213-02: Preparing for Part 2 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    Zambelli, J. [Spectrum Health, Grand Rapids, MI (United States)

    2015-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  8. MO-F-204-01: Preparing for Part 1 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    McKenney, S. [Children’s National Medical Center (United States)

    2016-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  9. MO-F-204-00: Preparing for the ABR Diagnostic and Nuclear Medical Physics Exams

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  10. MO-F-204-02: Preparing for Part 2 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    Szczykutowicz, T. [University Wisconsin-Madison (United States)

    2016-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  11. MO-F-204-03: Preparing for Part 3 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    Zambelli, J. [Spectrum Health Grand Rapids (United States)

    2016-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  12. WE-D-213-01: Preparing for Part 1 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    Simiele, S. [University of Wisconsin-Madison (United States)

    2015-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  13. WE-D-213-03: Preparing for Part 3 of the ABR Diagnostic Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    Bevins, N. [Henry Ford Health System, Detroit, MI (United States)

    2015-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  14. MO-F-204-00: Preparing for the ABR Diagnostic and Nuclear Medical Physics Exams

    International Nuclear Information System (INIS)

    2016-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  15. MO-F-204-01: Preparing for Part 1 of the ABR Diagnostic Physics Exam

    International Nuclear Information System (INIS)

    McKenney, S.

    2016-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  16. WE-D-213-03: Preparing for Part 3 of the ABR Diagnostic Physics Exam

    International Nuclear Information System (INIS)

    Bevins, N.

    2015-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  17. MO-F-204-02: Preparing for Part 2 of the ABR Diagnostic Physics Exam

    International Nuclear Information System (INIS)

    Szczykutowicz, T.

    2016-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  18. Lack of bcr and abr promotes hypoxia-induced pulmonary hypertension in mice.

    Directory of Open Access Journals (Sweden)

    Min Yu

    Full Text Available Bcr and Abr are GTPase activating proteins that specifically downregulate activity of the small GTPase Rac in restricted cell types in vivo. Rac1 is expressed in smooth muscle cells, a critical cell type involved in the pathogenesis of pulmonary hypertension. The molecular mechanisms that underlie hypoxia-associated pulmonary hypertension are not well-defined.Bcr and abr null mutant mice were compared to wild type controls for the development of pulmonary hypertension after exposure to hypoxia. Also, pulmonary arterial smooth muscle cells from those mice were cultured in hypoxia and examined for proliferation, p38 activation and IL-6 production. Mice lacking Bcr or Abr exposed to hypoxia developed increased right ventricular pressure, hypertrophy and pulmonary vascular remodeling. Perivascular leukocyte infiltration in the lungs was increased, and under hypoxia bcr-/- and abr-/- macrophages generated more reactive oxygen species. Consistent with a contribution of inflammation and oxidative stress in pulmonary hypertension-associated vascular damage, Bcr and Abr-deficient animals showed elevated endothelial leakage after hypoxia exposure. Hypoxia-treated pulmonary arterial smooth muscle cells from Bcr- or Abr-deficient mice also proliferated faster than those of wild type mice. Moreover, activated Rac1, phosphorylated p38 and interleukin 6 were increased in these cells in the absence of Bcr or Abr. Inhibition of Rac1 activation with Z62954982, a novel Rac inhibitor, decreased proliferation, p38 phosphorylation and IL-6 levels in pulmonary arterial smooth muscle cells exposed to hypoxia.Bcr and Abr play a critical role in down-regulating hypoxia-induced pulmonary hypertension by deactivating Rac1 and, through this, reducing both oxidative stress generated by leukocytes as well as p38 phosphorylation, IL-6 production and proliferation of pulmonary arterial smooth muscle cells.

  19. Gamma Knife Treatment of Brainstem Metastases

    Science.gov (United States)

    Peterson, Halloran E.; Larson, Erik W.; Fairbanks, Robert K.; MacKay, Alexander R.; Lamoreaux, Wayne T.; Call, Jason A.; Carlson, Jonathan D.; Ling, Benjamin C.; Demakas, John J.; Cooke, Barton S.; Peressini, Ben; Lee, Christopher M.

    2014-01-01

    The management of brainstem metastases is challenging. Surgical treatment is usually not an option, and chemotherapy is of limited utility. Stereotactic radiosurgery has emerged as a promising palliative treatment modality in these cases. The goal of this study is to assess our single institution experience treating brainstem metastases with Gamma Knife radiosurgery (GKRS). This retrospective chart review studied 41 patients with brainstem metastases treated with GKRS. The most common primary tumors were lung, breast, renal cell carcinoma, and melanoma. Median age at initial treatment was 59 years. Nineteen (46%) of the patients received whole brain radiation therapy (WBRT) prior to or concurrent with GKRS treatment. Thirty (73%) of the patients had a single brainstem metastasis. The average GKRS dose was 17 Gy. Post-GKRS overall survival at six months was 42%, at 12 months was 22%, and at 24 months was 13%. Local tumor control was achieved in 91% of patients, and there was one patient who had a fatal brain hemorrhage after treatment. Karnofsky performance score (KPS) >80 and the absence of prior WBRT were predictors for improved survival on multivariate analysis (HR 0.60 (p = 0.02), and HR 0.28 (p = 0.02), respectively). GKRS was an effective treatment for brainstem metastases, with excellent local tumor control. PMID:24886816

  20. Recovery of Abnormal ABR in Neonates and Infants at Risk of Hearing Loss

    Directory of Open Access Journals (Sweden)

    Ioannis Psarommatis

    2017-01-01

    Full Text Available The purpose of this retrospective study is to present the clinical experience of a single institution on the recovery of ABR thresholds in a large population of neonates and infants at risk of hearing loss. Potential prognostic factors associated with this phenomenon were also investigated. Out of 2248 high risk infants, 384 had abnormal ABR at initial hearing evaluation and 168 of them had absent ABR or a threshold ≥80 dBnHL. From this subgroup, a significant percentage showed complete or partial recovery on reexamination (32.7% and 9.3%, resp., performed 4–6 months later. The presence of normal otoacoustic emissions was associated with the ABR restoration on reexamination. Moreover, the very young age at the initial hearing screening seems to be related to higher probabilities of false positive ABR. The potential recovery of hearing in HR infants raises concerns about the very early cochlear implantation in HR infants less than one year. Such a treatment modality should be decided cautiously and only after obtaining valid and stable objective and subjective hearing thresholds. This holds especially true for infants showing an auditory neuropathy profile, as they presented a much greater probability of ABR recovery.

  1. Recovery of Abnormal ABR in Neonates and Infants at Risk of Hearing Loss.

    Science.gov (United States)

    Psarommatis, Ioannis; Voudouris, Charalampos; Kapetanakis, Ioannis; Athanasiadi, Faselida; Douros, Konstantinos

    2017-01-01

    The purpose of this retrospective study is to present the clinical experience of a single institution on the recovery of ABR thresholds in a large population of neonates and infants at risk of hearing loss. Potential prognostic factors associated with this phenomenon were also investigated. Out of 2248 high risk infants, 384 had abnormal ABR at initial hearing evaluation and 168 of them had absent ABR or a threshold ≥80 dBnHL. From this subgroup, a significant percentage showed complete or partial recovery on reexamination (32.7% and 9.3%, resp.), performed 4-6 months later. The presence of normal otoacoustic emissions was associated with the ABR restoration on reexamination. Moreover, the very young age at the initial hearing screening seems to be related to higher probabilities of false positive ABR. The potential recovery of hearing in HR infants raises concerns about the very early cochlear implantation in HR infants less than one year. Such a treatment modality should be decided cautiously and only after obtaining valid and stable objective and subjective hearing thresholds. This holds especially true for infants showing an auditory neuropathy profile, as they presented a much greater probability of ABR recovery.

  2. Brainstem tumors: Current management and future directions

    Directory of Open Access Journals (Sweden)

    Pablo F Recinos

    2012-01-01

    Full Text Available Tumors arising in the brainstem comprise 10-20% of all pediatric central nervous system (CNS tumors and account for a small percentage in adults. The prognosis for these tumors was considered uniformly poor prior to the era of modern neuroimaging and the location was fraught with disaster being considered a ′no man′s land′ for neurosurgeons. Following the introduction of advanced imaging modalities and neurophysiological monitoring, striking progress has occurred in the management of these lesions. Brainstem tumors are presently classified based on their anatomic location, focality, and histopathology. This article reviews the current classification of brainstem tumors, current management options, and future directions in the treatment for these rare tumors.

  3. Is enhanced MRI helpful in brainstem infarction?

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Y. M.; Shin, G. H.; Choi, W. S. [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1994-12-15

    To determine the role of MR contrast enhancement in evaluating time course of brainstem infarction. MR imaging with IV administration of gadopentetate dimeglumine was retrospectively reviewed in 43 patients with clinically and radiologically documented brainstem infarctions. The pattern of infarction was classified into spotty and patchy. Presence of parenchymal enhancement in infarction was evaluated. By location, there were 34 pontine, 3 midbrain, 6 medullary infarctions. The age of the infarctions ranged from 1 day to 9 months, with 5 patients scanned within 3 days and 10 scanned within 2 weeks of clinical ictus. Abnormalities on T2-weighted images were encountered in every case, with spotty pattern in 14 cases and patchy pattern in 29 cases. Parenchymal contrast enhancement was seen in 9 cases(20%), primarily occurring between days 8 and 20. MR contrast enhancement in brainstem infarction was infrequent that it may not be useful in the estimation of the age of infarction.

  4. Giant tubercular brainstem abscess: A case report

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    Pragati Chigurupati

    2014-01-01

    Full Text Available Tubercular brain abscesses are uncommon and tubercular brainstem abscesses are rarely reported. Most of these cases occur in immunocompromised patients. We report a case of giant brainstem abscess in a 5-year-old human immunodeficiency virus-seronegative female child who presented with complaints of headache, diplopia and unsteadiness of gait since 6 months. Diagnosis was made by a magnetic resonance imaging scan of brain. The patient demonstrated a remarkable clinical recovery after microsurgery combined with a course of antituberculous therapy. Microbiological and histological findings confirmed the diagnosis of a tuberculous abscess.

  5. Analyzing AbrB-Knockout Effects through Genome and Transcriptome Sequencing of Bacillus licheniformis DW2

    Science.gov (United States)

    Shu, Cheng-Cheng; Wang, Dong; Guo, Jing; Song, Jia-Ming; Chen, Shou-Wen; Chen, Ling-Ling; Gao, Jun-Xiang

    2018-01-01

    As an industrial bacterium, Bacillus licheniformis DW2 produces bacitracin which is an important antibiotic for many pathogenic microorganisms. Our previous study showed AbrB-knockout could significantly increase the production of bacitracin. Accordingly, it was meaningful to understand its genome features, expression differences between wild and AbrB-knockout (ΔAbrB) strains, and the regulation of bacitracin biosynthesis. Here, we sequenced, de novo assembled and annotated its genome, and also sequenced the transcriptomes in three growth phases. The genome of DW2 contained a DNA molecule of 4,468,952 bp with 45.93% GC content and 4,717 protein coding genes. The transcriptome reads were mapped to the assembled genome, and obtained 4,102∼4,536 expressed genes from different samples. We investigated transcription changes in B. licheniformis DW2 and showed that ΔAbrB caused hundreds of genes up-regulation and down-regulation in different growth phases. We identified a complete bacitracin synthetase gene cluster, including the location and length of bacABC, bcrABC, and bacT, as well as their arrangement. The gene cluster bcrABC were significantly up-regulated in ΔAbrB strain, which supported the hypothesis in previous study of bcrABC transporting bacitracin out of the cell to avoid self-intoxication, and was consistent with the previous experimental result that ΔAbrB could yield more bacitracin. This study provided a high quality reference genome for B. licheniformis DW2, and the transcriptome data depicted global alterations across two strains and three phases offered an understanding of AbrB regulation and bacitracin biosynthesis through gene expression. PMID:29599755

  6. Bayesian segmentation of brainstem structures in MRI

    DEFF Research Database (Denmark)

    Iglesias, Juan Eugenio; Van Leemput, Koen; Bhatt, Priyanka

    2015-01-01

    the brainstem structures in novel scans. Thanks to the generative nature of the scheme, the segmentation method is robust to changes in MRI contrast or acquisition hardware. Using cross validation, we show that the algorithm can segment the structures in previously unseen T1 and FLAIR scans with great accuracy...

  7. Neuromyelitis Optica Lesion Mimicking Brainstem Glioma

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2007-12-01

    Full Text Available A 12-year-old girl who presented with weakness of the left extremities and right sided sixth cranial nerve palsy had neuromyelitis optica (NMO mistaken for brainstem glioma on MRI, in a report from Brain Research Institute, Yonsei University College of Medicine,Seoul, Republic of KoreaNeuromyelitis Optica, Optic-Spinal Syndrome, Spectroscopy.

  8. Air pollution is associated with brainstem auditory nuclei pathology and delayed brainstem auditory evoked potentials.

    Science.gov (United States)

    Calderón-Garcidueñas, Lilian; D'Angiulli, Amedeo; Kulesza, Randy J; Torres-Jardón, Ricardo; Osnaya, Norma; Romero, Lina; Keefe, Sheyla; Herritt, Lou; Brooks, Diane M; Avila-Ramirez, Jose; Delgado-Chávez, Ricardo; Medina-Cortina, Humberto; González-González, Luis Oscar

    2011-06-01

    We assessed brainstem inflammation in children exposed to air pollutants by comparing brainstem auditory evoked potentials (BAEPs) and blood inflammatory markers in children age 96.3±8.5 months from highly polluted (n=34) versus a low polluted city (n=17). The brainstems of nine children with accidental deaths were also examined. Children from the highly polluted environment had significant delays in wave III (t(50)=17.038; p7.501; p<0.0001), consisting with delayed central conduction time of brainstem neural transmission. Highly exposed children showed significant evidence of inflammatory markers and their auditory and vestibular nuclei accumulated α synuclein and/or β amyloid(1-42). Medial superior olive neurons, critically involved in BAEPs, displayed significant pathology. Children's exposure to urban air pollution increases their risk for auditory and vestibular impairment. Copyright © 2011 ISDN. Published by Elsevier Ltd. All rights reserved.

  9. Two ABREs, two redundant root-specific and one W-box cis-acting elements are functional in the sunflower HAHB4 promoter.

    Science.gov (United States)

    Manavella, Pablo A; Dezar, Carlos A; Ariel, Federico D; Chan, Raquel L

    2008-10-01

    HAHB4 is a sunflower gene encoding a homeodomain-leucine zipper (HD-Zip) transcription factor. It was previously demonstrated that this gene is regulated at the transcriptional level by several abiotic factors and hormones. A previous analysis in the PLACE database revealed the presence of four putative ABREs. In this work these four elements and also one W-box and two root-specific expression elements were characterized as functional. Site-directed mutagenesis on the promoter, stable transformation of Arabidopis plants as well as transient transformation of sunflower leaves, were performed. The analysis of the transformants was carried out by histochemistry and real time RT-PCR. The results indicate that just one ABRE out of the four is responsible for ABA, NaCl and drought regulation. However, NaCl induction occurs also by an additional ABA-independent way involving another two overlapped ABREs. On the other hand, it was determined that the W-box located 5' upstream is responsive to ethylene and only two root-specific expression elements, among the several detected, are functional but redundant. Conservation of molecular mechanisms between sunflower and Arabidopsis is strongly supported by this experimental work.

  10. Planeamiento estratégico de la empresa ABR Lagos S.A.C.

    OpenAIRE

    Zuloeta Lagos, Bujarin Jaime

    2016-01-01

    La presente investigación tiene por finalidad desarrollar un Plan Estratégico para la empresa ABR Lagos S.A.C. para el periodo 2016-2020, con lo cual se busca consolidar su permanencia en el mercado peruano, incrementar su rentabilidad y mejorar la calidad del servicio. ABR Lagos S.A.C. es una empresa especializada en la fabricación e instalación de estructuras metálicas, la cual con casi siete años en el mercado ha mostrado un significativo crecimiento en las ventas. Para el logro del objeti...

  11. PEATE automático em recém nascidos de risco: estudo da sensibilidade e especificidade Automatic ABR in newborns risk: study of sensitivity and specificity

    Directory of Open Access Journals (Sweden)

    Rosanna Mariangela Giaffredo Angrisani

    2012-04-01

    female gender. Evaluation procedures consisted of transient otoacoustic emissions(TOAEs, A-ABR and diagnostic ABR carried out in the same week. RESULTS: from the 186 evaluated newborns, 156 (83.9% showed normal hearing. Conductive hearing loss was verified in nine neonates (4.8%, seven bilateral and two unilateral. Cochlear hearing loss was observed in five neonates (2.7%, one unilateral and four bilateral. Central evidences were observed in eleven neonates (5.9% and one neonate was diagnosed with auditory neuropathy spectrum disorder (0,5%. In four cases, we found a maturational delay in the first evaluation with normal result within one month. In the comparison of A-ABR with diagnostic ABR, high sensitivity rates were observed (99% and higher in the identification of cochlear, conductive, central and auditory neuropathy. Specificity rate of A-ABR was 100% for auditory neuropathy, 75% for right ear and 60% for left ear cochlear hearing losses and 54.5% for right ear and 63.6% for the left ear central abnormalities. For conductive hearing losses, specificity was low (lower than 43%. CONCLUSION: A-ABR was efficient in the identification of auditory neuropathies with high sensitivity and specificity rates. However, false negative responses were observed in the group diagnosed with cochlear and conductive hearing losses, central abnormalities and maturational delay.

  12. Towards an optimal paradigm for simultaneously recording cortical and brainstem auditory evoked potentials.

    Science.gov (United States)

    Bidelman, Gavin M

    2015-02-15

    Simultaneous recording of brainstem and cortical event-related brain potentials (ERPs) may offer a valuable tool for understanding the early neural transcription of behaviorally relevant sounds and the hierarchy of signal processing operating at multiple levels of the auditory system. To date, dual recordings have been challenged by technological and physiological limitations including different optimal parameters necessary to elicit each class of ERP (e.g., differential adaptation/habitation effects and number of trials to obtain adequate response signal-to-noise ratio). We investigated a new stimulus paradigm for concurrent recording of the auditory brainstem frequency-following response (FFR) and cortical ERPs. The paradigm is "optimal" in that it uses a clustered stimulus presentation and variable interstimulus interval (ISI) to (i) achieve the most ideal acquisition parameters for eliciting subcortical and cortical responses, (ii) obtain an adequate number of trials to detect each class of response, and (iii) minimize neural adaptation/habituation effects. Comparison between clustered and traditional (fixed, slow ISI) stimulus paradigms revealed minimal change in amplitude or latencies of either the brainstem FFR or cortical ERP. The clustered paradigm offered over a 3× increase in recording efficiency compared to conventional (fixed ISI presentation) and thus, a more rapid protocol for obtaining dual brainstem-cortical recordings in individual listeners. We infer that faster recording of subcortical and cortical potentials might allow more complete and sensitive testing of neurophysiological function and aid in the differential assessment of auditory function. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Cerebral and brainstem electrophysiologic activity during euthanasia with pentobarbital sodium in horses.

    Science.gov (United States)

    Aleman, M; Williams, D C; Guedes, A; Madigan, J E

    2015-01-01

    An overdose of pentobarbital sodium administered i.v. is the most commonly used method of euthanasia in veterinary medicine. Determining death after the infusion relies on the observation of physical variables. However, it is unknown when cortical electrical activity and brainstem function are lost in a sequence of events before death. To examine changes in the electrical activity of the cerebral cortex and brainstem during an overdose of pentobarbital sodium solution for euthanasia. Our testing hypothesis is that isoelectric pattern of the brain in support of brain death occurs before absence of electrocardiogram (ECG) activity. Fifteen horses requiring euthanasia. Prospective observational study. Horses with neurologic, orthopedic, and cardiac illnesses were selected and instrumented for recording of electroencephalogram, electrooculogram, brainstem auditory evoked response (BAER), and ECG. Physical and neurologic (brainstem reflexes) variables were monitored. Loss of cortical electrical activity occurred during or within 52 seconds after the infusion of euthanasia solution. Cessation of brainstem function as evidenced by a lack of brainstem reflexes and disappearance of the BAER happened subsequently. Despite undetectable heart sounds, palpable arterial pulse, and mean arterial pressure, recordable ECG was the last variable to be lost after the infusion (5.5-16 minutes after end of the infusion). Overdose of pentobarbital sodium solution administered i.v. is an effective, fast, and humane method of euthanasia. Brain death occurs within 73-261 seconds of the infusion. Although absence of ECG activity takes longer to occur, brain death has already occurred. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  14. Interictal dysfunction of a brainstem descending modulatory center in migraine patients.

    Directory of Open Access Journals (Sweden)

    Eric A Moulton

    Full Text Available The brainstem contains descending circuitry that can modulate nociceptive processing (neural signals associated with pain in the dorsal horn of the spinal cord and the medullary dorsal horn. In migraineurs, abnormal brainstem function during attacks suggest that dysfunction of descending modulation may facilitate migraine attacks, either by reducing descending inhibition or increasing facilitation. To determine whether a brainstem dysfunction could play a role in facilitating migraine attacks, we measured brainstem function in migraineurs when they were not having an attack (i.e. the interictal phase.Using fMRI (functional magnetic resonance imaging, we mapped brainstem activity to heat stimuli in 12 episodic migraine patients during the interictal phase. Separate scans were collected to measure responses to 41 degrees C and noxious heat (pain threshold+1 degrees C. Stimuli were either applied to the forehead on the affected side (as reported during an attack or the dorsum of the hand. This was repeated in 12 age-gender-matched control subjects, and the side tested corresponded to that in the matched migraine patients. Nucleus cuneiformis (NCF, a component of brainstem pain modulatory circuits, appears to be hypofunctional in migraineurs. 3 out of the 4 thermal stimulus conditions showed significantly greater NCF activation in control subjects than the migraine patients.Altered descending modulation has been postulated to contribute to migraine, leading to loss of inhibition or enhanced facilitation resulting in hyperexcitability of trigeminovascular neurons. NCF function could potentially serve as a diagnostic measure in migraine patients, even when not experiencing an attack. This has important implications for the evaluation of therapies for migraine.

  15. Magnetic resonance imaging in the evaluation of the brainstem

    International Nuclear Information System (INIS)

    Han, J.S.; Bonstelle, C.T.; Kaufman, B.; Benson, J.E.; Alfidi, R.J.; Clampitt, M.; Van Dyke, C.; Huss, R.G.

    1984-01-01

    Magnetic resonance (MR) images of the brainstem region from 100 normal or asymptomatic individuals were reviewed in addition to those of 17 patients with intra-axial brainstem lesions and 15 patients with extra-axial masses around the brainstem. MR was able to demonstrate consistently the normal anatomy of the brainstem and adjacent cisterns, though the distinction between gray and white matter was seldom possible with the present technology. Masses in and around the brainstem were all accurately identified on MR and its sensitivity was superior to that of x-ray computed tomography (CT). These study results show that despite its technical limitations, MR is presently the examination of choice for the evaluation of brainstem abnormalities and eventually it will undoubtedly replace metrizamide CT cisternography

  16. Evaluation of peripheral auditory pathways and brainstem in obstructive sleep apnea

    Directory of Open Access Journals (Sweden)

    Erika Matsumura

    Full Text Available Abstract Introduction Obstructive sleep apnea causes changes in normal sleep architecture, fragmenting it chronically with intermittent hypoxia, leading to serious health consequences in the long term. It is believed that the occurrence of respiratory events during sleep, such as apnea and hypopnea, can impair the transmission of nerve impulses along the auditory pathway that are highly dependent on the supply of oxygen. However, this association is not well established in the literature. Objective To compare the evaluation of peripheral auditory pathway and brainstem among individuals with and without obstructive sleep apnea. Methods The sample consisted of 38 adult males, mean age of 35.8 (±7.2, divided into four groups matched for age and Body Mass Index. The groups were classified based on polysomnography in: control (n = 10, mild obstructive sleep apnea (n = 11 moderate obstructive sleep apnea (n = 8 and severe obstructive sleep apnea (n = 9. All study subjects denied a history of risk for hearing loss and underwent audiometry, tympanometry, acoustic reflex and Brainstem Auditory Evoked Response. Statistical analyses were performed using three-factor ANOVA, 2-factor ANOVA, chi-square test, and Fisher's exact test. The significance level for all tests was 5%. Results There was no difference between the groups for hearing thresholds, tympanometry and evaluated Brainstem Auditory Evoked Response parameters. An association was observed between the presence of obstructive sleep apnea and changes in absolute latency of wave V (p = 0.03. There was an association between moderate obstructive sleep apnea and change of the latency of wave V (p = 0.01. Conclusion The presence of obstructive sleep apnea is associated with changes in nerve conduction of acoustic stimuli in the auditory pathway in the brainstem. The increase in obstructive sleep apnea severity does not promote worsening of responses assessed by audiometry, tympanometry and Brainstem

  17. Evaluation of peripheral auditory pathways and brainstem in obstructive sleep apnea.

    Science.gov (United States)

    Matsumura, Erika; Matas, Carla Gentile; Magliaro, Fernanda Cristina Leite; Pedreño, Raquel Meirelles; Lorenzi-Filho, Geraldo; Sanches, Seisse Gabriela Gandolfi; Carvallo, Renata Mota Mamede

    2016-11-25

    Obstructive sleep apnea causes changes in normal sleep architecture, fragmenting it chronically with intermittent hypoxia, leading to serious health consequences in the long term. It is believed that the occurrence of respiratory events during sleep, such as apnea and hypopnea, can impair the transmission of nerve impulses along the auditory pathway that are highly dependent on the supply of oxygen. However, this association is not well established in the literature. To compare the evaluation of peripheral auditory pathway and brainstem among individuals with and without obstructive sleep apnea. The sample consisted of 38 adult males, mean age of 35.8 (±7.2), divided into four groups matched for age and Body Mass Index. The groups were classified based on polysomnography in: control (n=10), mild obstructive sleep apnea (n=11) moderate obstructive sleep apnea (n=8) and severe obstructive sleep apnea (n=9). All study subjects denied a history of risk for hearing loss and underwent audiometry, tympanometry, acoustic reflex and Brainstem Auditory Evoked Response. Statistical analyses were performed using three-factor ANOVA, 2-factor ANOVA, chi-square test, and Fisher's exact test. The significance level for all tests was 5%. There was no difference between the groups for hearing thresholds, tympanometry and evaluated Brainstem Auditory Evoked Response parameters. An association was observed between the presence of obstructive sleep apnea and changes in absolute latency of wave V (p=0.03). There was an association between moderate obstructive sleep apnea and change of the latency of wave V (p=0.01). The presence of obstructive sleep apnea is associated with changes in nerve conduction of acoustic stimuli in the auditory pathway in the brainstem. The increase in obstructive sleep apnea severity does not promote worsening of responses assessed by audiometry, tympanometry and Brainstem Auditory Evoked Response. Copyright © 2016 Associação Brasileira de

  18. Avaliação dos achados ao exame dos potenciais evocados do tronco cerebral em indivíduos com síndrome de West Evaluation of the brainstem evoked potentials in West syndrome

    Directory of Open Access Journals (Sweden)

    Alfredo Lopes Pereira Filho

    2004-01-01

    Full Text Available A síndrome de West é um tipo de espasmo infantil caracterizado por encefalopatia epiléptica associado a espasmos em flexão e deficiência mental de instalação no primeiro ano de vida e de etiologia incerta. Acredita-se ser determinada por diferentes fatores etiológicos como infeção intrauterina, esclerose tuberosa, asfixia perinatal ou afecções pós-natais. FORMA DE ESTUDO: Observacional coorte com corte transversal. MATERIAL E MÉTODO: No presente estudo dez pacientes com Síndrome de West foram submetidos ao exame de Potencial Evocado de Tronco Cerebral (BERA para avaliar o envolvimento do tronco cerebral e das vias auditivas a este nível. RESULTADO: Os achados anormais ao BERA incluem alteração na morfologia das curvas com reprodutibilidade apenas de onda I e II, (caso 7, aumento do intervalo interpico da onda I-V (casos 1, 2 e 9, aumento da proporção de amplitude da onda I/V (caso 8 e alteração do limiar eletrofisiológico (caso 7. Tais achados ao BERA sugerem que a disfunção do sistema nervoso resulte principalmente da hipogênese ou degeneração das células nervosas, em parte como resultado da dismielinização. CONCLUSÃO: Os autores recomendam o uso de estudos eletrofisiológicos para avaliar a disfunção do sistema nervoso central no paciente com suspeita de espasmo infantil.The West syndrome is a pediatric disease that involves muscular spasm, mental deficiency and epileptic encephalopathy. This disease tends to be noticed in the first year of life and has no etiology known. It is believed to be caused by different etiology factors as uterine infection, tuberous sclerosis, perinatal asphyxia, or post-born diseases. STUDY DESIGN: Observacional cohort with transversal cut. MATERIAL AND METHOD: In this study, ten West Syndrome patients were submitted to Auditory Brainstem Response (ABR to evaluate the involvement of the hearing system. RESULTS: The abnormal results consisted in morphological alterations (case 7

  19. Brainstem tolerance to conformal radiotherapy of skull base tumors

    International Nuclear Information System (INIS)

    Debus, J.; Hug, E.B.; Liebsch, N.J.; O'Farrel, D.; Finkelstein, D.; Efird, J.; Munzenrider, J.E.

    1997-01-01

    Purpose: The aim of this study was to analyze the long-term incidence of brainstem toxicity in patients treated for skull base tumors with high dose conformal radiotherapy. Methods and Materials: Between 1974 and 1995, 367 patients with chordomas (n = 195) and chondrosarcomas (n = 172) of the base of skull have been treated with combined megavoltage photon and 160 MeV proton radiotherapy. Following 3D treatment planning with delineation of target volumes and critical nontarget structures dose distributions and dose-volume histograms were calculated. Radiotherapy was given an 1.8 Gy or CGE (=Cobalt Gray Equivalent) dose per fraction, with prescribed target doses ranging from 63 CGE to 79.2 CGE (mean = 67.8 CGE). Doses to the brainstem surface were limited to ≤64 CGE and to the brainstem center to ≤53 CGE. Results: Follow-up time ranged from 6 months to 21.4 years (mean = 42.5 months). Brainstem toxicity was observed in 17 of 367 patients attributable to treatment, resulting in death of three patients. Actuarial rates of 5 and 10-year high-grade toxicity-free survival were 94 and 88%, respectively. Increased risk of brainstem toxicity was significantly associated with maximum dose to brainstem, volume of brainstem receiving ≥50 CGE, ≥55 CGE, and ≥60 CGE, number of surgical procedures, and prevalence of diabetes or high blood pressure. Multivariate analysis identified three independent factors as important prognosticators: number of surgical procedures (p < 0.001), volume of the brainstem receiving 60 CGE (p < 0.001), and prevalence of diabetes (p < 0.01). Conclusions: Tolerance of brainstem to fractionated radiotherapy appears to be a steep function of tissue volume included in high dose regions rather than the maximum dose of brainstem alone. In addition, presence of predisposing factors as well as extent of surgical manipulation can significantly lower brainstem tolerance in the individual patient

  20. Investigation of auditory brainstem function in elderly diabetic patients with presbycusis.

    Science.gov (United States)

    Kovacií, Jelena; Lajtman, Zoran; Ozegović, Ivan; Knezević, Predrag; Carić, Tomislav; Vlasić, Ana

    2009-01-01

    We performed brainstem auditory evoked potential (BAEP) examinations in 100 patients older than 60 years and having type I diabetes mellitus and presbycusis. The aim of our investigation was to compare the BAEP results of this group with those of healthy controls with presbycusis and to look for possible correlations between alteration of the auditory brainstem function and the aging of elderly diabetic patients. Absolute and interpeak latencies of all waves were prolonged significantly in the study group of diabetic patients. The amplitudes of all waves I through V were diminished in the study group as compared to those in the control group, with statistical significance present for all waves. Analysis of the latencies (waves I, II, I, and V), interpeak latencies (I-V), and amplitudes (I, II, III, and V) of BAEP revealed a significant difference between those of diabetics and those of healthy elderly controls with presbycusis. These data support a hypothesis that there is a brainstem neuropathy in diabetes mellitus that can be assessed with auditory brainstem response testing even in the group of elderly patients with sensorineural hearing loss.

  1. Brainstem auditory evoked potentials in horses

    Directory of Open Access Journals (Sweden)

    Juliana Almeida Nogueira da Gama

    2016-04-01

    Full Text Available ABSTRACT: The brainstem auditory evoked potential (BAEP evaluates the integrity of the auditory pathways to the brainstem. The aim of this study was to evoke BAEPs in 21 clinically normal horses. The animals were sedated with detomidine hydrochloride (0.013mg.kg-1 BW. Earphones were inserted and rarefaction clicks at 90 dB and noise masking at 40 dB were used. After performing the test, the latencies of waves (I, II, III, IV, and V and interpeaks(I-III, III-V, and I-V were identified. The mean latencies of the waves were as follows: wave I, 2.4 ms; wave II, 2.24 ms; wave III, 3.61ms; wave IV, 4.61ms; and wave V, 5.49ms. The mean latencies of the interpeaks were as follows: I-III, 1.37ms; III-V, 1.88ms; and I-V, 3.26ms. This is the first study using BAEPs in horses in Brazil, and the observed latencies will be used as normative data for the interpretation of tests performed on horses with changes related to auditory system or neurologic abnormalities.

  2. [Optimization of Energy Saving Measures with ABR-MBR Integrated Process].

    Science.gov (United States)

    Wu, Peng; Lu, Shuang-jun; Xu, Yue-zhong; Liu, Jie; Shen, Yao-liang

    2015-08-01

    High energy consumption and membrane fouling are important factors that limit the wide use of membrane bioreactor (MBR). In order to reduce energy consumption and delay the process of membrane fouling, the process of anaerobic baffled reactor (ABR)-MBR was used to treat domestic sewage. The structure of the process and conditions of nitrogen and phosphorus removal were optimized in this study. The results showed that energy consumption was reduced by 43% through optimizing the structure of ABR-MBR process. Meanwhile, the process achieved a high level of COD, NH: -N, TN and TP removal, with the average removal efficiencies of 91%, 85%, 76% and 86%, respectively. In addition, the added particulate media could effectively delay membrane fouling, while the formation process of membrane fouling was changed. The extracted amount of carbohydrates increased while the amount of proteins decreased. Finally, the potential was enhanced for the practical application of MBR.

  3. Feasibility of an Anaerobic Baffled Reactor (ABR In Treating Starch Industry Wastewater

    Directory of Open Access Journals (Sweden)

    Ali Assadi

    2007-03-01

    Full Text Available The anaerobic baffled reactor (ABR includes a mixed anaerobic culture separated into compartments and a novel process with a series of vertical baffles at each compartment. It dose not require granulation for its operation, resulting in shorter start-up time. In this study, the feasibility of the ABR process was investigated for the treatment of wheat flour starch wastewater. Simple gravity settling was used to remove suspended solids from the starch wastewater and used as feed. Start-up of a reactor (13.5L with five compartments using a diluted feed of approximately 4500 mg/L chemical oxygen demand (COD was accomplished in about 9 weeks using seed sludge from the anaerobic digester of a municipal wastewater treatment plant. The reactor with a hydraulic retention time (HRT of 72 h at 35°C and an initial organic loading rate (OLR of 1.2 kgCOD/m3.d showed a removal efficiency of 61% COD. The best reactor performance was observed with an organic loading rate of 2.5 kgCOD/m3.d (or hydraulic retention time of 2.45 d when a COD conversion of 67% was achieved. The main advantage of using an ABR comes from its compartmentalized structure. The first compartment of an ABR may act as a buffer zone to all toxic and inhibitory materials in the feed and, thus, allows the later compartments to be loaded with a relatively harmless, more uniform, and mostly acidified influent. In this respect, the later compartments would be more likely to support active populations of the relatively sensitive methanogenic bacteria.

  4. Brainstem Auditory Evoked Potential in HIV-Positive Adults.

    Science.gov (United States)

    Matas, Carla Gentile; Samelli, Alessandra Giannella; Angrisani, Rosanna Giaffredo; Magliaro, Fernanda Cristina Leite; Segurado, Aluísio C

    2015-10-20

    To characterize the findings of brainstem auditory evoked potential in HIV-positive individuals exposed and not exposed to antiretroviral treatment. This research was a cross-sectional, observational, and descriptive study. Forty-five HIV-positive individuals (18 not exposed and 27 exposed to the antiretroviral treatment - research groups I and II, respectively - and 30 control group individuals) were assessed through brainstem auditory evoked potential. There were no significant between-group differences regarding wave latencies. A higher percentage of altered brainstem auditory evoked potential was observed in the HIV-positive groups when compared to the control group. The most common alteration was in the low brainstem. HIV-positive individuals have a higher percentage of altered brainstem auditory evoked potential that suggests central auditory pathway impairment when compared to HIV-negative individuals. There was no significant difference between individuals exposed and not exposed to antiretroviral treatment.

  5. Clinical Approach to Supranuclear Brainstem Saccadic Gaze Palsies

    Directory of Open Access Journals (Sweden)

    Alexandra Lloyd-Smith Sequeira

    2017-08-01

    Full Text Available Failure of brainstem supranuclear centers for saccadic eye movements results in the clinical presence of a brainstem-mediated supranuclear saccadic gaze palsy (SGP, which is manifested as slowing of saccades with or without range of motion limitation of eye movements and as loss of quick phases of optokinetic nystagmus. Limitation in the range of motion of eye movements is typically worse with saccades than with smooth pursuit and is overcome with vestibular–ocular reflexive eye movements. The differential diagnosis of SGPs is broad, although acute-onset SGP is most often from brainstem infarction and chronic vertical SGP is most commonly caused by the neurodegenerative condition progressive supranuclear palsy. In this review, we discuss the brainstem anatomy and physiology of the brainstem saccade-generating network; we discuss the clinical features of SGPs, with an emphasis on insights from quantitative ocular motor recordings; and we consider the broad differential diagnosis of SGPs.

  6. MRI findings of multiple sclerosis involving the brainstem

    International Nuclear Information System (INIS)

    Park, Jeong Hoon; Jeong, Hae Woong; Kim, Hyun Jin; Cho, Jae Kwoeng; Kim, Chang Soo

    2001-01-01

    To describe MRI findings of multiple sclerosis involving the brainstem. Among 35 cases of clinically definite multiple sclerosis, the authors retrospectively analysed 20 in which the brainstem was involved. MR images were analysed with regard to involvement sites in the brainstem or other locations, signal intensity, multiplicity, shape, enhancement pattern, and contiguity of brainstem lesions with cisternal or ventricular CSF space. The brainstem was the only site of involvement in five cases (25%), while simultaneous involvement of the brainstem and other sites was observed in 15 cases (75%). No case involved only the midbrain or medulla oblongata, and simultaneous involvement of the midbrain, pons and medulla oblongata was noted in 12 cases (60%). The most frequently involved region of the brainstem was the medulla oblongata (n=13; 90%), followed by the pons (n=17; 85%) and the midbrain (n=16; 80%). Compared with normal white matter, brainstem lesions showed low signal intensity on T1 weighted images, and high signal intensity on T2 weighted, proton density weighted, and FLAIR images. In 17 cases (85%), multiple intensity was observed, and the shape of lesions varied: oval, round, elliptical, patchy, crescentic, confluent or amorphous were seen on axial MR images, and in 14 cases (82%), coronal or sagittal scanning showed that lesions were long and tubular. Contiguity between brainstem lesions and cisternal or ventricular CSF space was seen in all cases (100%) involving midbrain (16/16) and medulla oblongata (18/18) and in 15 of 17 (88%) involving the pons. Contrast enhancement was apparent in 7 of 12 cases (58%). In the brainstem, MRI demonstrated partial or total contiguity between lesions and cisternal or ventricular CSF space, and coronal or sagittal images showed that lesions were long and tubuler

  7. Will available bit rate (ABR) services give us the capability to offer virtual LANs over wide-area ATM networks?

    Science.gov (United States)

    Ferrandiz, Ana; Scallan, Gavin

    1995-10-01

    The available bit rate (ABR) service allows connections to exceed their negotiated data rates during the life of the connections when excess capacity is available in the network. These connections are subject to flow control from the network in the event of network congestion. The ability to dynamically adjust the data rate of the connection can provide improved utilization of the network and be a valuable service to end users. ABR type service is therefore appropriate for the transmission of bursty LAN traffic over a wide area network in a manner that is more efficient and cost effective than allocating bandwdith at the peak cell rate. This paper describes the ABR service and discusses if it is realistic to operate a LAN like service over a wide area using ABR.

  8. Intermittent hypercapnic hypoxia effects on the nicotinic acetylcholine receptors in the developing piglet hippocampus and brainstem.

    Science.gov (United States)

    Vivekanandarajah, Arunnjah; Aishah, Atqiya; Waters, Karen A; Machaalani, Rita

    2017-05-01

    This study investigated the effects of acute (1 day) vs repeated (4 days) exposure to intermittent hypercapnic hypoxia (IHH) on the immunohistochemical expression of α2, α3, α5, α7, α9 and β2 nicotinic acetylcholine receptor (nAChR) subunits in the developing piglet hippocampus and brainstem medulla, and how prior nicotine exposure alters the response to acute IHH. Five piglet groups included: 1day IHH (1D IHH, n=9), 4days IHH (4D IHH, n=8), controls exposed only to air cycles for 1day (1D Air, n=6) or 4days (4D Air, n=5), and pre-exposed to nicotine for 13days prior to 1day IHH (Nic+1D IHH, n=7). The exposure period alternated 6min of HH (8%O 2 , 7%CO 2 , balance N 2 ) and 6min of air over 48min, while controls were switched from air-to-air. Results showed that: 1. repeated IHH induces more changes in nAChR subunit expression than acute IHH in both the hippocampus and brainstem medulla, 2. In the hippocampus, α2 and β2 changed the most (increased) following IHH and the CA3, CA2 and DG were mostly affected. In the brainstem medulla, α2, α5, α9 and β2 were changed (decreased) in most nuclei with the hypoglossal and nucleus of the solitary tract being mostly affected. 3. Pre-exposure to nicotine enhanced the changes in the hippocampus but dampened those in the brainstem medulla. These findings indicate that the nAChRs (predominantly with the α2/β2 complex) are affected by IHH in critical hippocampal and brainstem nuclei during early brain development, and that pre-exposure to nicotine alters the pattern of susceptibility to IHH. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. WE-D-213-04: Preparing for Parts 2 & 3 of the ABR Nuclear Medicine Physics Exam

    International Nuclear Information System (INIS)

    MacDougall, R.

    2015-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  10. WE-D-213-04: Preparing for Parts 2 & 3 of the ABR Nuclear Medicine Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    MacDougall, R. [Children’s Hospital (United States)

    2015-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR professional certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All three parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation and skill sets necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those aspects that are unique to the nuclear exam. Medical physicists who have recently completed each of part of the ABR exam will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to Prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear imaging physics

  11. MO-F-204-04: Preparing for Parts 2 & 3 of the ABR Nuclear Medicine Physics Exam

    International Nuclear Information System (INIS)

    MacDougall, R.

    2016-01-01

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  12. MO-F-204-04: Preparing for Parts 2 & 3 of the ABR Nuclear Medicine Physics Exam

    Energy Technology Data Exchange (ETDEWEB)

    MacDougall, R. [Boston Children’s Hospital (United States)

    2016-06-15

    Adequate, efficient preparation for the ABR Diagnostic and Nuclear Medical Physics exams is key to successfully obtain ABR certification. Each part of the ABR exam presents its own challenges: Part I: Determine the scope of basic medical physics study material, efficiently review this material, and solve related written questions/problems. Part II: Understand imaging principles, modalities, and systems, including image acquisition, processing, and display. Understand the relationship between imaging techniques, image quality, patient dose and safety, and solve related written questions/problems. Part III: Gain crucial, practical, clinical medical physics experience. Effectively communicate and explain the practice, performance, and significance of all aspects of clinical medical physics. All parts of the ABR exam require specific skill sets and preparation: mastery of basic physics and imaging principles; written problem solving often involving rapid calculation; responding clearly and succinctly to oral questions about the practice, methods, and significance of clinical medical physics. This symposium focuses on the preparation necessary for each part of the ABR exam. Although there is some overlap, the nuclear exam covers a different body of knowledge than the diagnostic exam. A separate speaker will address those unique aspects of the nuclear exam, and how preparing for a second specialty differs from the first. Medical physicists who recently completed each ABR exam portion will share their experiences, insights, and preparation methods to help attendees best prepare for the challenges of each part of the ABR exam. In accordance with ABR exam security policy, no recalls or exam questions will be discussed. Learning Objectives: How to prepare for Part 1 of the ABR exam by determining the scope of basic medical physics study material and related problem solving/calculations How to prepare for Part 2 of the ABR exam by understanding diagnostic and/or nuclear

  13. Potenciais Evocados Auditivos de Estado Estável no diagnóstico audiológico infantil: uma comparação com os Potenciais Evocados Auditivos de Tronco Encefálico Steady-state auditory evoked responses in audiological diagnosis in children: a comparison with brainstem evoked auditory responses

    Directory of Open Access Journals (Sweden)

    Gabriela Ribeiro Ivo Rodrigues

    2010-02-01

    Full Text Available Os Potenciais Evocados Auditivos de Estado Estável (PEAEE têm sido apontados como uma técnica promissora na avaliação audiológica infantil. OBJETIVO: Investigar o nível de concordância entre os resultados dos PEAEE e dos Potenciais Evocados Auditivos de Tronco Encefálico (PEATE-clique em um grupo de crianças com perda auditiva sensorioneural, averiguando assim a aplicabilidade clínica desta técnica na avaliação audiológica infantil. FORMA DE ESTUDO: Clínico prospectivo de coorte transversal. MATERIAL E MÉTODO: 15 crianças com idade entre dois e 36 meses e diagnóstico de perda auditiva sensorioneural. A concordância entre as respostas dos dois testes foi avaliada por meio do coeficiente de correlação intraclasse e o teste de McNemar comparou os dois testes quanto à probabilidade de ocorrência de resposta. RESULTADOS: Os coeficientes de correlação encontrados foram 0,70; 0,64; 0,49; 0,69; 0,63 e 0,68 respectivamente para as frequências de 1, 2, 4, 1-2, 2-4 e 1-2-4kHz. No teste de McNemar foi obtido p=0.000, indicando que a probabilidade de se obter resposta presente nos dois testes não é igual, sendo maior nos PEAEE. CONCLUSÃO: A boa concordância observada entre as técnicas sugere que um exame pode ser complementar ao outro. Os PEAEE, entretanto, promoveram informações adicionais nos casos de perdas severas e profundas, acrescentando dados importantes para a reabilitação destas crianças e proporcionando maior precisão no diagnóstico audiológico.Auditory Steady-State Responses (ASSR are being recognized as a promising technique in the assessment of hearing in children. AIM: To investigate the agreement level between results obtained from ASSR and click-ABR in a group of children with sensorineural hearing loss, in order to study the clinical applicability of this technique to evaluate the hearing status in young children. STUDY DESIGN: clinical prospective with a cross-sectional cohort. MATERIALS AND METHODS

  14. Intracranial neurenteric cyst traversing the brainstem

    Directory of Open Access Journals (Sweden)

    Jasmit Singh

    2015-01-01

    Full Text Available Neurenteric cysts (NECs, also called enterogenous cysts, are rare benign endodermal lesions of the central nervous system that probably result from separation failure of the notochord and upper gastrointestinal tract. Most frequently they are found in the lower cervical spine or the upper thoracic spine. Intracranial occurrence is rare and mostly confined to infratentorial compartment, in prepontine region [51%]. Other common locations are fourth ventricle and cerebellopontine angle. There are few reports of NEC in medulla or the cerebellum. Because of the rarity of the disease and common radiological findings, they are misinterpreted as arachnoid or simple cysts until the histopathological confirmation, unless suspected preoperatively. We herein report a rare yet interesting case of intracranial NEC traversing across the brainstem.

  15. A brainstem variant of reversible posterior leukoencephalopathy syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Kitaguchi, H.; Tomimoto, H.; Terada, K. [Kyoto University, Department of Neurology, Graduate School of Medicine, Sakyo-ku, Kyoto (Japan); Miki, Y.; Yamamoto, A. [Kyoto University, Department of Nuclear Medicine and Diagnostic Imaging, Graduate School of Medicine, Sakyo-ku, Kyoto (Japan); Satoi, H.; Kanda, M. [Ijinkai Takeda General Hospital, Department of Neurology, Fushimi-ku, Kyoto (Japan); Fukuyama, H. [Kyoto University, Human Brain Research Center, Graduate School of Medicine, Sakyo-ku, Kyoto (Japan)

    2005-09-01

    Reversible posterior leukoencephalopathy syndrome (RPLS) is caused by various heterogeneous factors, the commonest being hypertension, followed by nonhypertensive causes such as eclampsia, renal diseases and immunosuppressive therapy. Patients with RPLS exhibit bilateral white and gray matter abnormalities in the posterior aspects of the cerebral hemispheres. However, this syndrome may affect the brainstem predominantly, and these cases are designated as hypertensive brainstem encephalopathy. We present here two patients with reversible brainstem encephalopathy: one with hypertension and the other without hypertension. These patients presented with swelling and diffuse hyperintensities of the brainstem in fluid-attenuated inversion-recovery (FLAIR) and T2-weighted MRI, but with relatively mild clinical symptoms. They recovered without major neurological deficits, but had residual lacunar lesions in the pons. Reversible brainstem encephalopathy with characteristic MRI features was found in both hypertensive and nonhypertensive patients. These patients were diagnosed with a brainstem variant of RPLS, which is potentially fully reversible after an adequate treatment, and therefore should be carefully differentiated from other brainstem disease conditions. (orig.)

  16. A brainstem variant of reversible posterior leukoencephalopathy syndrome

    International Nuclear Information System (INIS)

    Kitaguchi, H.; Tomimoto, H.; Terada, K.; Miki, Y.; Yamamoto, A.; Satoi, H.; Kanda, M.; Fukuyama, H.

    2005-01-01

    Reversible posterior leukoencephalopathy syndrome (RPLS) is caused by various heterogeneous factors, the commonest being hypertension, followed by nonhypertensive causes such as eclampsia, renal diseases and immunosuppressive therapy. Patients with RPLS exhibit bilateral white and gray matter abnormalities in the posterior aspects of the cerebral hemispheres. However, this syndrome may affect the brainstem predominantly, and these cases are designated as hypertensive brainstem encephalopathy. We present here two patients with reversible brainstem encephalopathy: one with hypertension and the other without hypertension. These patients presented with swelling and diffuse hyperintensities of the brainstem in fluid-attenuated inversion-recovery (FLAIR) and T2-weighted MRI, but with relatively mild clinical symptoms. They recovered without major neurological deficits, but had residual lacunar lesions in the pons. Reversible brainstem encephalopathy with characteristic MRI features was found in both hypertensive and nonhypertensive patients. These patients were diagnosed with a brainstem variant of RPLS, which is potentially fully reversible after an adequate treatment, and therefore should be carefully differentiated from other brainstem disease conditions. (orig.)

  17. Time-varying auditory gain control in response to double-pulse stimuli in harbour porpoises is not mediated by a stapedial reflex

    Directory of Open Access Journals (Sweden)

    Asger Emil Munch Schrøder

    2017-04-01

    Full Text Available Echolocating animals reduce their output level and hearing sensitivity with decreasing echo delays, presumably to stabilize the perceived echo intensity during target approaches. In bats, this variation in hearing sensitivity is formed by a call-induced stapedial reflex that tapers off over time after the call. Here, we test the hypothesis that a similar mechanism exists in toothed whales by subjecting a trained harbour porpoise to a series of double sound pulses varying in delay and frequency, while measuring the magnitudes of the evoked auditory brainstem responses (ABRs. We find that the recovery of the ABR to the second pulse is frequency dependent, and that a stapedial reflex therefore cannot account for the reduced hearing sensitivity at short pulse delays. We propose that toothed whale auditory time-varying gain control during echolocation is not enabled by the middle ear as in bats, but rather by frequency-dependent mechanisms such as forward masking and perhaps higher-order control of efferent feedback to the outer hair cells.

  18. Specificity determinants for the abscisic acid response element ?

    OpenAIRE

    Sarkar, Aditya Kumar; Lahiri, Ansuman

    2013-01-01

    Abscisic acid (ABA) response elements (ABREs) are a group of cis-acting DNA elements that have been identified from promoter analysis of many ABA-regulated genes in plants. We are interested in understanding the mechanism of binding specificity between ABREs and a class of bZIP transcription factors known as ABRE binding factors (ABFs). In this work, we have modeled the homodimeric structure of the bZIP domain of ABRE binding factor 1 from Arabidopsis thaliana (AtABF1) and studied its interac...

  19. Arterial territories of human brain: brainstem and cerebellum

    International Nuclear Information System (INIS)

    Tatu, L.; Moulin, T.; Bogousslavsky, J.; Duvernoy, H.

    1997-01-01

    The development of neuroimaging has allowed clinicians to improve clinico-anatomic correlations in patients with strokes. Brainstem and cerebellum structures are well delineated on MRI, but there is a lack of standardization in their arterial supply. We present a system of 12 brainstem and cerebellum axial sections, depicting the dominant arterial territories and the most important anatomic structures. These sections may be used as a practical tool to determine arterial territories on MRI, and may help establish consistent clinico-anatomic correlations in patients with brainstem and cerebellar ischemic strokes. (authors)

  20. Effectiveness of interferon-[beta], ACNU, and radiation therapy in pediatric patients with brainstem glioma

    Energy Technology Data Exchange (ETDEWEB)

    Wakabayashi, Toshihiko; Yoshida, Jun; Mizuno, Masaaki; Sugita, Kenichiro [Nagoya Univ. (Japan). Faculty of Medicine; Kito, Akira

    1992-12-01

    Sixteen pediatric patients with brainstem glioma were treated with a combination of interferon-[beta], 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl -3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU), and radiation therapy (IAR therapy). All patients received 1-1.5 million IU/day of interferon-[beta] intravenously for 1 week of each 6-week cycle. In addition, ACNU (2-3 mg/kg) was given on the 2nd day of each cycle. Conventional focal irradiation (1.5-2 Gy/day for 5 days to a total dosage of 40-60 Gy) was administered beginning on day 3. Patients underwent at least two 6-week cycles. Adverse effects included nausea, vomiting, and myelosuppression, but were mild and transient. Response to treatment was evaluated by the reduction in tumor size measured on postcontrast computed tomographic scans and magnetic resonance images. Responses occurred in 10 of 11 patients with the intrinsic type of brainstem glioma, including three complete and seven partial responses. Two of the five patients with exophytic type gliomas partially responded. The median survival was 15.7 months, a remarkable improvement over the natural course of this disease. These results indicate that IAR therapy is a useful primary treatment for pediatric patients with brainstem gliomas. (author).

  1. MO-F-16A-03: AAPM Online Learning Support of New ABR MOC Requirements

    International Nuclear Information System (INIS)

    Bloch, C; Ogburn, J; Woodward, M

    2014-01-01

    In 2002 the American Board of Radiology (ABR) discontinued issuing lifetime board certification. After that time diplomates received a timelimited certificate and must participate in the Maintenance of Certification (MOC) program in order to maintain their certification. Initially certificates were issued with a 10 year expiration period and the MOC had requirements to be met over that 10 year period. The goal was to demonstrate continuous maintenance of clinical competency, however some diplomates were attempting to fulfill most or all of the requirements near the end of the 10 year period. This failed to meet the continuous aspect of the goal and so the ABR changed to a sliding 3-year window. This was done to recognize that not every year would be the same, but that diplomates should be able to maintain a reasonable average over any 3 year period.A second significant change occurred in 2013. The initial requirements included 20 selfassessment modules (SAMs) over the original 10 year term. SAMs are a special type of continuing education (CE) credit that were an addition to the 250 standard CE credits required over the 10 year period. In 2013, however, the new requirement is 75 CE credits over the previous 3 years, of which 25 must include self-assessment. Effectively this raised the self-assessment requirement from 20 in 10 years to 25 in 3 years. Previously SAMs were an interactive presentation available in limited quantities at live meetings. However, the new requirement is not for SAMs but CE-SA which includes SAMs, but also includes the online quizzes provided at the AAPM online learning center. All credits earned at the AAPM online learning center fulfill the ABR SA requirement.This talk will be an interactive demonstration of the AAPM online learning center along with a discussion of the MOC requirements

  2. Brainstem neurons survive the identical ischemic stress that kills higher neurons: insight to the persistent vegetative state.

    Directory of Open Access Journals (Sweden)

    C Devin Brisson

    Full Text Available Global ischemia caused by heart attack, pulmonary failure, near-drowning or traumatic brain injury often damages the higher brain but not the brainstem, leading to a 'persistent vegetative state' where the patient is awake but not aware. Approximately 30,000 U.S. patients are held captive in this condition but not a single research study has addressed how the lower brain is preferentially protected in these people. In the higher brain, ischemia elicits a profound anoxic depolarization (AD causing neuronal dysfunction and vasoconstriction within minutes. Might brainstem nuclei generate less damaging AD and so be more resilient? Here we compared resistance to acute injury induced from simulated ischemia by 'higher' hippocampal and striatal neurons versus brainstem neurons in live slices from rat and mouse. Light transmittance (LT imaging in response to 10 minutes of oxygen/glucose deprivation (OGD revealed immediate and acutely damaging AD propagating through gray matter of neocortex, hippocampus, striatum, thalamus and cerebellar cortex. In adjacent brainstem nuclei, OGD-evoked AD caused little tissue injury. Whole-cell patch recordings from hippocampal and striatal neurons under OGD revealed sudden membrane potential loss that did not recover. In contrast brainstem neurons from locus ceruleus and mesencephalic nucleus as well as from sensory and motor nuclei only slowly depolarized and then repolarized post-OGD. Two-photon microscopy confirmed non-recoverable swelling and dendritic beading of hippocampal neurons during OGD, while mesencephalic neurons in midbrain appeared uninjured. All of the above responses were mimicked by bath exposure to 100 µM ouabain which inhibits the Na+/K+ pump or to 1-10 nM palytoxin which converts the pump into an open cationic channel. Therefore during ischemia the Na+/K+ pump of higher neurons fails quickly and extensively compared to naturally resilient hypothalamic and brainstem neurons. The selective survival

  3. The Dictyostelium Bcr/Abr-related protein DRG regulates both Rac- and Rab-dependent pathways

    OpenAIRE

    Knetsch, Menno L.W.; Schäfers, Nicole; Horstmann, Heinz; Manstein, Dietmar J.

    2001-01-01

    Dictyostelium discoideum DdRacGap1 (DRG) contains both Rho-GEF and Rho-GAP domains, a feature it shares with mammalian Bcr and Abr. To elucidate the physiological role of this multifunctional protein, we characterized the enzymatic activity of recombinant DRG fragments in vitro, created DRG-null cells, and studied the function of the protein in vivo by analysing the phenotypic changes displayed by DRG-depleted cells and DRG-null cells complemented with DRG or DRG fragments. Our results show t...

  4. Enterovirus 71 Brainstem Encephalitis and Cognitive and Motor Deficits

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2006-12-01

    Full Text Available Follow-up studies were conducted in 63 previously healthy children with enterovirus 71 brainstem encephalitis (49 stage II, 7 stage Ilia, and 7 stage Illb at National Cheng Kung University Hospital, Tainan, Taiwan.

  5. Brainstem and cerebellar changes after cerebrovascular accidents: magnetic resonance imaging

    International Nuclear Information System (INIS)

    Uchino, A.; Takase, Y.; Nomiyama, K.; Egashira, R.; Kudo, S.

    2006-01-01

    We illustrate the various types of secondary degeneration in the brainstem and/or cerebellum detected on magnetic resonance (MR) images obtained after cerebrovascular accidents. The changes include: (a) ipsilateral nigral degeneration after striatal infarction; (b) Wallerian degeneration of the pyramidal tract in the brainstem after supratentorial pyramidal tract or motor cortex injury; (c) Wallerian degeneration of the corticopontine tract in the brainstem after frontal lobe infarction; (d) ipsilateral brainstem atrophy and crossed cerebellar atrophy due to an extensive supratentorial lesion; (e) ipsilateral superior cerebellar peduncle atrophy, contralateral rubral degeneration, contralateral inferior olivary degeneration and ipsilateral cerebellar atrophy after dentate nucleus hemorrhage; (f) ipsilateral inferior olivary degeneration after pontine tegmentum hemorrhage; (g) bilateral wallerian degeneration of the pontocerebellar tracts after ventromedial pontine infarction or basis pontis hemorrhage; and (h) ipsilateral cerebellar atrophy after middle cerebellar peduncle hemorrhage. (orig.)

  6. Brainstem and cerebellar changes after cerebrovascular accidents: magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, A.; Takase, Y.; Nomiyama, K.; Egashira, R.; Kudo, S. [Saga Medical School, Department of Radiology, Saga (Japan)

    2006-03-15

    We illustrate the various types of secondary degeneration in the brainstem and/or cerebellum detected on magnetic resonance (MR) images obtained after cerebrovascular accidents. The changes include: (a) ipsilateral nigral degeneration after striatal infarction; (b) Wallerian degeneration of the pyramidal tract in the brainstem after supratentorial pyramidal tract or motor cortex injury; (c) Wallerian degeneration of the corticopontine tract in the brainstem after frontal lobe infarction; (d) ipsilateral brainstem atrophy and crossed cerebellar atrophy due to an extensive supratentorial lesion; (e) ipsilateral superior cerebellar peduncle atrophy, contralateral rubral degeneration, contralateral inferior olivary degeneration and ipsilateral cerebellar atrophy after dentate nucleus hemorrhage; (f) ipsilateral inferior olivary degeneration after pontine tegmentum hemorrhage; (g) bilateral wallerian degeneration of the pontocerebellar tracts after ventromedial pontine infarction or basis pontis hemorrhage; and (h) ipsilateral cerebellar atrophy after middle cerebellar peduncle hemorrhage. (orig.)

  7. Musicians and Tone-Language Speakers Share Enhanced Brainstem Encoding but Not Perceptual Benefits for Musical Pitch

    Science.gov (United States)

    Bidelman, Gavin M.; Gandour, Jackson T.; Krishnan, Ananthanarayan

    2011-01-01

    Behavioral and neurophysiological transfer effects from music experience to language processing are well-established but it is currently unclear whether or not linguistic expertise (e.g., speaking a tone language) benefits music-related processing and its perception. Here, we compare brainstem responses of English-speaking musicians/non-musicians…

  8. Brainstem encoding of speech and musical stimuli in congenital amusia: Evidence from Cantonese speakers

    Directory of Open Access Journals (Sweden)

    Fang eLiu

    2015-01-01

    Full Text Available Congenital amusia is a neurodevelopmental disorder of musical processing that also impacts subtle aspects of speech processing. It remains debated at what stage(s of auditory processing deficits in amusia arise. In this study, we investigated whether amusia originates from impaired subcortical encoding of speech (in quiet and noise and musical sounds in the brainstem. Fourteen Cantonese-speaking amusics and 14 matched controls passively listened to six Cantonese lexical tones in quiet, two Cantonese tones in noise (signal-to-noise ratios at 0 and 20 dB, and two cello tones in quiet while their frequency-following responses (FFRs to these tones were recorded. All participants also completed a behavioral lexical tone identification task. The results indicated normal brainstem encoding of pitch in speech (in quiet and noise and musical stimuli in amusics relative to controls, as measured by FFR pitch strength, pitch error, and stimulus-to-response correlation. There was also no group difference in neural conduction time or FFR amplitudes. Both groups demonstrated better FFRs to speech (in quiet and noise than to musical stimuli. However, a significant group difference was observed for tone identification, with amusics showing significantly lower accuracy than controls. Analysis of the tone confusion matrices suggested that amusics were more likely than controls to confuse between tones that shared similar acoustic features. Interestingly, this deficit in lexical tone identification was not coupled with brainstem abnormality for either speech or musical stimuli. Together, our results suggest that the amusic brainstem is not functioning abnormally, although higher-order linguistic pitch processing is impaired in amusia. This finding has significant implications for theories of central auditory processing, requiring further investigations into how different stages of auditory processing interact in the human brain.

  9. Brainstem encoding of speech and musical stimuli in congenital amusia: evidence from Cantonese speakers.

    Science.gov (United States)

    Liu, Fang; Maggu, Akshay R; Lau, Joseph C Y; Wong, Patrick C M

    2014-01-01

    Congenital amusia is a neurodevelopmental disorder of musical processing that also impacts subtle aspects of speech processing. It remains debated at what stage(s) of auditory processing deficits in amusia arise. In this study, we investigated whether amusia originates from impaired subcortical encoding of speech (in quiet and noise) and musical sounds in the brainstem. Fourteen Cantonese-speaking amusics and 14 matched controls passively listened to six Cantonese lexical tones in quiet, two Cantonese tones in noise (signal-to-noise ratios at 0 and 20 dB), and two cello tones in quiet while their frequency-following responses (FFRs) to these tones were recorded. All participants also completed a behavioral lexical tone identification task. The results indicated normal brainstem encoding of pitch in speech (in quiet and noise) and musical stimuli in amusics relative to controls, as measured by FFR pitch strength, pitch error, and stimulus-to-response correlation. There was also no group difference in neural conduction time or FFR amplitudes. Both groups demonstrated better FFRs to speech (in quiet and noise) than to musical stimuli. However, a significant group difference was observed for tone identification, with amusics showing significantly lower accuracy than controls. Analysis of the tone confusion matrices suggested that amusics were more likely than controls to confuse between tones that shared similar acoustic features. Interestingly, this deficit in lexical tone identification was not coupled with brainstem abnormality for either speech or musical stimuli. Together, our results suggest that the amusic brainstem is not functioning abnormally, although higher-order linguistic pitch processing is impaired in amusia. This finding has significant implications for theories of central auditory processing, requiring further investigations into how different stages of auditory processing interact in the human brain.

  10. Brainstem encoding of speech and musical stimuli in congenital amusia: evidence from Cantonese speakers

    Science.gov (United States)

    Liu, Fang; Maggu, Akshay R.; Lau, Joseph C. Y.; Wong, Patrick C. M.

    2015-01-01

    Congenital amusia is a neurodevelopmental disorder of musical processing that also impacts subtle aspects of speech processing. It remains debated at what stage(s) of auditory processing deficits in amusia arise. In this study, we investigated whether amusia originates from impaired subcortical encoding of speech (in quiet and noise) and musical sounds in the brainstem. Fourteen Cantonese-speaking amusics and 14 matched controls passively listened to six Cantonese lexical tones in quiet, two Cantonese tones in noise (signal-to-noise ratios at 0 and 20 dB), and two cello tones in quiet while their frequency-following responses (FFRs) to these tones were recorded. All participants also completed a behavioral lexical tone identification task. The results indicated normal brainstem encoding of pitch in speech (in quiet and noise) and musical stimuli in amusics relative to controls, as measured by FFR pitch strength, pitch error, and stimulus-to-response correlation. There was also no group difference in neural conduction time or FFR amplitudes. Both groups demonstrated better FFRs to speech (in quiet and noise) than to musical stimuli. However, a significant group difference was observed for tone identification, with amusics showing significantly lower accuracy than controls. Analysis of the tone confusion matrices suggested that amusics were more likely than controls to confuse between tones that shared similar acoustic features. Interestingly, this deficit in lexical tone identification was not coupled with brainstem abnormality for either speech or musical stimuli. Together, our results suggest that the amusic brainstem is not functioning abnormally, although higher-order linguistic pitch processing is impaired in amusia. This finding has significant implications for theories of central auditory processing, requiring further investigations into how different stages of auditory processing interact in the human brain. PMID:25646077

  11. ABFs, a family of ABA-responsive element binding factors.

    Science.gov (United States)

    Choi, H; Hong, J; Ha, J; Kang, J; Kim, S Y

    2000-01-21

    Abscisic acid (ABA) plays an important role in environmental stress responses of higher plants during vegetative growth. One of the ABA-mediated responses is the induced expression of a large number of genes, which is mediated by cis-regulatory elements known as abscisic acid-responsive elements (ABREs). Although a number of ABRE binding transcription factors have been known, they are not specifically from vegetative tissues under induced conditions. Considering the tissue specificity of ABA signaling pathways, factors mediating ABA-dependent stress responses during vegetative growth phase may thus have been unidentified so far. Here, we report a family of ABRE binding factors isolated from young Arabidopsis plants under stress conditions. The factors, isolated by a yeast one-hybrid system using a prototypical ABRE and named as ABFs (ABRE binding factors) belong to a distinct subfamily of bZIP proteins. Binding site selection assay performed with one ABF showed that its preferred binding site is the strong ABRE, CACGTGGC. ABFs can transactivate an ABRE-containing reporter gene in yeast. Expression of ABFs is induced by ABA and various stress treatments, whereas their induction patterns are different from one another. Thus, a new family of ABRE binding factors indeed exists that have the potential to activate a large number of ABA/stress-responsive genes in Arabidopsis.

  12. Summary report on safety and licensing strategy support for the ABR prototype

    International Nuclear Information System (INIS)

    Cahalan, J. E.; Nuclear Engineering Division

    2007-01-01

    Argonne National Laboratory is providing support to the US Department of Energy in the Global Nuclear Energy Partnership (GNEP) in certification of an advanced, sodium-cooled fast reactor. The reactor is to be constructed as a prototype for future commercial power reactors that will produce electricity while consuming actinides recovered from light water reactor spent fuel. This prototype reactor has been called the Advanced Burner Reactor, or ABR, and is now often referred to as the advanced recycle reactor. As part of its activities, Argonne is providing technical services to assist definition of a safety and licensing strategy for the ABR prototype, and to further implementation of the strategy. In FY06, an organizational meeting was held for DOE and its laboratory contractors to discuss licensing alternatives and review previous licensing experience for the Fast Flux Test Facility (FFTF) and the Clinch River Breeder Reactor Plant (CRBRP). Near the end of FY06, a report summarizing the discussions and conclusions was written. One of the top-level conclusions recorded in the report was a recommendation to follow a licensing strategy that included the US Nuclear Regulatory Commission (NRC) as the regulatory review and licensing authority. In FY07, activities ar Argonne to support safety and licensing progress have continued. These activities have focused on further evaluation of licensing alternatives; assessment of design, analysis, and documentation implications of licensing paths; and initial technical interactions with the Nuclear Regulatory Commission. This report summarizes FY07 activities

  13. [Formation Mechanism of Aerobic Granular Sludge and Removal Efficiencies in Integrated ABR-CSTR Reactor].

    Science.gov (United States)

    Wu, Kai-cheng; Wu, Peng; Xu, Yue-zhong; Li, Yue-han; Shen, Yao-liang

    2015-08-01

    Anaerobic Baffled Reactor (ABR) was altered to make an integrated anaerobic-aerobic reactor. The research investigated the mechanism of aerobic sludge granulation, under the condition of continuous-flow. The last two compartments of the ABR were altered into aeration tank and sedimentation tank respectively with seeded sludge of anaerobic granular sludge in anaerobic zone and conventional activated sludge in aerobic zone. The HRT was gradually decreased in sedimentation tank from 2.0 h to 0.75 h and organic loading rate was increased from 1.5 kg x (M3 x d)(-1) to 2.0 kg x (M3 x d)(-1) while the C/N of 2 was controlled in aerobic zone. When the system operated for 110 days, the mature granular sludge in aerobic zone were characterized by compact structure, excellent sedimentation performance (average sedimentation rate was 20.8 m x h(-1)) and slight yellow color. The system performed well in nitrogen and phosphorus removal under the conditions of setting time of 0.75 h and organic loading rate of 2.0 kg (m3 x d)(-1) in aerobic zone, the removal efficiencies of COD, NH4+ -N, TP and TN were 90%, 80%, 65% and 45%, respectively. The results showed that the increasing selection pressure and the high organic loading rate were the main propulsions of the aerobic sludge granulation.

  14. ABrIL - Advanced Brain Imaging Lab : a cloud based computation environment for cooperative neuroimaging projects.

    Science.gov (United States)

    Neves Tafula, Sérgio M; Moreira da Silva, Nádia; Rozanski, Verena E; Silva Cunha, João Paulo

    2014-01-01

    Neuroscience is an increasingly multidisciplinary and highly cooperative field where neuroimaging plays an important role. Neuroimaging rapid evolution is demanding for a growing number of computing resources and skills that need to be put in place at every lab. Typically each group tries to setup their own servers and workstations to support their neuroimaging needs, having to learn from Operating System management to specific neuroscience software tools details before any results can be obtained from each setup. This setup and learning process is replicated in every lab, even if a strong collaboration among several groups is going on. In this paper we present a new cloud service model - Brain Imaging Application as a Service (BiAaaS) - and one of its implementation - Advanced Brain Imaging Lab (ABrIL) - in the form of an ubiquitous virtual desktop remote infrastructure that offers a set of neuroimaging computational services in an interactive neuroscientist-friendly graphical user interface (GUI). This remote desktop has been used for several multi-institution cooperative projects with different neuroscience objectives that already achieved important results, such as the contribution to a high impact paper published in the January issue of the Neuroimage journal. The ABrIL system has shown its applicability in several neuroscience projects with a relatively low-cost, promoting truly collaborative actions and speeding up project results and their clinical applicability.

  15. Partial Nitrification and Denitrifying Phosphorus Removal in a Pilot-Scale ABR/MBR Combined Process.

    Science.gov (United States)

    Wu, Peng; Xu, Lezhong; Wang, Jianfang; Huang, Zhenxing; Zhang, Jiachao; Shen, Yaoliang

    2015-11-01

    A pilot-scale combined process consisting of an anaerobic baffled reactor (ABR) and an aerobic membrane bioreactor (MBR) for the purpose of achieving easy management, low energy demands, and high efficiencies on nutrient removal from municipal wastewater was investigated. The process operated at room temperature with hydraulic retention time (HRT) of 7.5 h, recycle ratio 1 of 200%, recycle ratio 2 of 100%, and dissolved oxygen (DO) of 1 mg/L and achieved good effluent quality with chemical oxygen demand (COD) of 25 mg/L, NH4 (+)-N of 4 mg/L, total nitrogen (TN) of 11 mg/L, and total phosphorus (TP) of 0.7 mg/L. The MBR achieved partial nitrification, and NO2 (-)-N has been accumulated (4 mg/L). Efficient short-cut denitrification was occurred in the ABR with a TN removal efficiency of 51%, while the role of denitrification and phosphorus removal removed partial TN (14%). Furthermore, nitrogen was further removed (11%) by simultaneous nitrification and denitrification in the MBR. In addition, phosphorus accumulating organisms in the MBR sufficiently uptake phosphorus; thus, effluent TP further reduced with a TP removal efficiency of 84%. Analysis of fluorescence in situ hybridization (FISH) showed that ammonia oxidizing bacteria (AOB) and phosphorus accumulating organisms (PAOs) were enriched in the process. In addition, the accumulation of NO2 (-)-N was contributed to the inhibition on the activities of the NOB rather than its elimination.

  16. Characterization of three multicopper oxidases in the filamentous fungus Podospora anserina: A new role of an ABR1-like protein in fungal development?

    Science.gov (United States)

    Xie, Ning; Ruprich-Robert, Gwenaël; Silar, Philippe; Herbert, Eric; Ferrari, Roselyne; Chapeland-Leclerc, Florence

    2018-07-01

    The Podospora anserina genome contains a large family of 15 multicopper oxidases (MCOs), including three genes encoding a FET3-like protein, an ABR1-like protein and an ascorbate oxidase (AO)-like protein. FET3, ABR1 and AO1 are involved in global laccase-like activity since deletion of the relevant genes led to a decrease of activity when laccase substrate (ABTS) was used as substrate. However, contrary to the P. anserina MCO proteins previously characterized, none of these three MCOs seemed to be involved in lignocellulose degradation and in resistance to phenolic compounds and oxidative stress. We showed that the bulk of ferroxidase activity was clearly due to ABR1, and only in minor part to FET3, although ABR1 does not contain all the residues typical of FET3 proteins. Moreover, we showed that ABR1, related to the Aspergillus fumigatus ABR1 protein, was clearly and specifically involved in pigmentation of ascospores. Surprisingly, phenotypes were more severe in mutants lacking both abr1 and ao1. Deletion of the ao1 gene led to an almost total loss of AO activity. No direct involvement of AO1 in fungal developmental process in P. anserina was evidenced, except in a abr1 Δ background. Overall, unlike other previously characterized MCOs, we thus evidence a clear involvement of ABR1 protein in fungal development. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Lung inflammation induces IL-1β expression in hypoglossal neurons in rat brainstem

    Science.gov (United States)

    Jafri, Anjum; Belkadi, Abdelmadjid; Zaidi, Syed I. A.; Getsy, Paulina; Wilson, Christopher G.; Martin, Richard J.

    2013-01-01

    Perinatal inflammation is associated with respiratory morbidity. Immune modulation of brainstem respiratory control centers may provide a link for this pathobiology. We exposed 11-day old rats to intratracheal lipopolysaccharide (LPS, 0.5 µg/g) to test the hypothesis that intrapulmonary inflammation increases expression of the proinflammatory cytokine IL-1β within respiratory-related brainstem regions. Intratracheal LPS resulted in a 32% increase in IL-1β protein expression in the medulla oblongata. In situ hybridization showed increased intensity of IL-1β mRNA but no change in neuronal numbers. Co-localization experiments showed that hypoglossal neurons express IL-1β mRNA and immunostaining showed a 43% increase in IL-1β protein-expressing cells after LPS exposure. LPS treatment also significantly increased microglial cell numbers though they did not express IL-1β mRNA. LPS-induced brainstem expression of neuronal IL-1β mRNA and protein may have implications for our understanding of the vulnerability of neonatal respiratory control in response to a peripheral pro-inflammatory stimulus. PMID:23648475

  18. Brainstem tolerance to conformal radiotherapy of skull base tumors

    International Nuclear Information System (INIS)

    Debus, J.; Hug, E.B.; Munzenrider, J.E.; Liebsch, N.J.; O'Farrell, D.; Efird, J.; Daly, W.; Suit, H.D.

    1996-01-01

    Purpose/Objective: Brainstem tolerance to inhomogenous radiation doses applied by modern conformal radiotherapy has not yet been examined. The aim of this study was to analyse the incidence of brainstem toxicity in patients treated for skull base tumors with high dose conformal radiotherapy. Materials and Methods: Between 1974 and 1995, 367 patients with chordomas (n=195) and chondrosarcomas (n=172) of the base of skull have been treated with combined megavoltage photon and 160 MeV proton radiotherapy. All patients had previously undergone biopsy, subtotal or total tumor removal. 104 patients had two or more surgical procedures before radiotherapy. Following 3D treatment planning with delineation of target volumes and critical non-target structures, dose distributions and dose volume histograms were calculated [at the time of treatment delivery]. Radiotherapy was given once a day, 1.8 Gy or CGE (Cobalt Gy Equivalent: Proton Gy X 1.1) per fraction, 5 fractions per week, with prescribed target doses ranging from 63 CGE to 79.2 CGE (mean = 67.8 CGE). Doses to the brainstem surface were limited to ≤64 CGE and to the brainstem center to ≤53 CGE. Dose distributions were developed to limit dose to brainstem surface and center; current plans limit dose to surface and center to ≤64 CGE and ≤53 CGE, respectively. Brainstem toxicity was scored according to the RTOG grading system. Results: Follow-up ranged from 6 months to 21.4 years (mean = 42.5 months). Brainstem symptoms, attributable to the treatment, developed in 17 of 282 patients with local tumor control (6.0%), resulting in death of three patients. The mean time to onset of symptoms was 17 months (range: 4.5 to 177 months). These symptoms appeared in 89.5% within 3 years. Grading of the brainstem toxicity is listed in table 1. Actuarial rates of 5 and 10 year toxicity free survival were 87% and 82% respectively. Increased risk of brainstem toxicity was significantly associated with maximum brainstem dose

  19. Cortical and brainstem plasticity in Tourette syndrome and obsessive-compulsive disorder.

    Science.gov (United States)

    Suppa, Antonio; Marsili, Luca; Di Stasio, Flavio; Berardelli, Isabella; Roselli, Valentina; Pasquini, Massimo; Cardona, Francesco; Berardelli, Alfredo

    2014-10-01

    Gilles de la Tourette syndrome is characterized by motor/vocal tics commonly associated with psychiatric disorders, including obsessive-compulsive disorder. We investigated primary motor cortex and brainstem plasticity in Tourette patients, exposed and unexposed to chronic drug treatment, with and without psychiatric disturbances. We also investigated primary motor cortex and brainstem plasticity in obsessive-compulsive disorder. We studied 20 Tourette patients with and without psychiatric disturbances, 15 with obsessive-compulsive disorder, and 20 healthy subjects. All groups included drug-naïve patients. We conditioned the left primary motor cortex with intermittent/continuous theta-burst stimulation and recorded motor evoked potentials. We conditioned the supraorbital nerve with facilitatory/inhibitory high-frequency stimulation and recorded the blink reflex late response area. In healthy subjects, intermittent theta-burst increased and continuous theta-burst stimulation decreased motor evoked potentials. Differently, intermittent theta-burst failed to increase and continuous theta-burst stimulation failed to decrease motor evoked potentials in Tourette patients, with and without psychiatric disturbances. In obsessive-compulsive disorder, intermittent/continuous theta-burst stimulation elicited normal responses. In healthy subjects and in subjects with obsessive-compulsive disorder, the blink reflex late response area increased after facilitatory high-frequency and decreased after inhibitory high-frequency stimulation. Conversely, in Tourette patients, with and without psychiatric disturbances, facilitatory/inhibitory high-frequency stimulation left the blink reflex late response area unchanged. Theta-burst and high-frequency stimulation elicited similar responses in drug-naïve and chronically treated patients. Tourette patients have reduced plasticity regardless of psychiatric disturbances. These findings suggest that abnormal plasticity contributes to the

  20. Audiometria de resposta evocada de acordo com sexo e idade: achados e aplicabilidade Evoked response audiometry according to gender and age: findings and usefulness

    Directory of Open Access Journals (Sweden)

    Edmir Américo Lourenço

    2008-08-01

    Full Text Available A audiometria de respostas evocadas (ABR é um registro não-invasivo de potenciais elétricos auditivos nos primeiros 12 milissegundos, da orelha média ao córtex auditivo. ABR é importante na avaliação otoneurológica. OBJETIVO: Esclarecer as utilidades do exame, faixas etárias e sexo com maior incidência e topodiagnóstico segundo as latências absolutas e os intervalos interpicos. CASUÍSTICA E MÉTODO: Neste estudo retrospectivo foram analisados 403 prontuários de ABR realizados em clínica particular na cidade de Jundiaí/SP, Brasil, suspeitos de alteração auditiva e/ou doença do SNC, com os pacientes divididos por sexo e faixa etária. RESULTADOS E CONCLUSÕES: ABR é um importante exame para determinar a integridade da via auditiva, limiares eletrofisiológicos e topodiagnóstico, embora o teste não indique a etiologia das alterações. Foi demonstrado que ocorreu maior incidência de achados retrococleares na faixa etária de 12-20 anos e sexo masculino, contudo crianças menores de um ano com fatores de risco não apresentaram um aumento na incidência de alterações condutivas, cocleares e retrococleares em relação à população geral estudada. As latências absolutas das ondas I, III e V foram maiores no sexo masculino e as alterações dos intervalos interpicos foram similares em ambos os sexos, sendo que o intervalo I-III foi o mais freqüentemente alterado.Auditory evoked brainstem responses (ABR is a non-invasive electrical potential registration which evaluates the auditory tract from the middle ear to the auditory cortex in the first 12 milliseconds (ms. The ABR is an important otoneurological evaluation. AIM: confirm the test's usefulness, major incidence and topography according to are range gender considering the absolute latencies of the waves and interpeak intervals. MATERIALS AND METHOD: we retrospectively analyzed 403 tests from a private clinic in the city of Jundiaí-São Paulo State-Brazil, from

  1. Vestibular myogenic and acoustical brainstem evoked potentials in neurological practice

    Directory of Open Access Journals (Sweden)

    O. S. Korepina

    2012-01-01

    Full Text Available Along with the inspection of acoustical cortex and brainstem EP in neurologic, otoneurologic and audiologic practice recently start to use so-called vestibular evoked myogenic potentials (VEMP. It is shown, that at ear stimulation by a loud sound and record of sterno-cleidomastoid contraction is possible to estimate function of the inferior vestibular nerve and vestibulospinal pathways, a sacculo-cervical reflex. In article some methodical and clinical questions of application of these kinds are presented. Combine research acoustic brainstem EP and VEMP allows to confirm effectively lesions of acoustical and vestibular ways at brainstem. The conclusion becomes, that this kind of inspection is important for revealing demielinisation and defeats in vestibulospinal tract, that quite often happens at MS, and at estimation of efficiency of treatment

  2. Magnetic resonance imaging in brain-stem tumors

    International Nuclear Information System (INIS)

    Nomura, Mikio; Saito, Hisazumi; Akino, Minoru; Abe, Hiroshi.

    1988-01-01

    Four patients with brain-stem tumors underwent magnetic resonance imaging (MRI) before and after radiotherapy. The brain-stem tumors were seen as a low signal intensity on T1-weighted images and as a high signal intensity on T2-weighted images. A tumor and its anatomic involvement were more clearly visualized on MRI than on cuncurrently performed CT. Changes in tumor before and after radiotherapy could be determined by measuring the diameter of tumor on sagittal and coronal images. This allowed quantitative evaluation of the reduction of tumor in association with improvement of symptoms. The mean T1 value in the central part of tumors was shortened in all patients after radiotherapy. The results indicate that MRI may assist in determining the effect of radiotherapy for brain-stem tumors. (Namekawa, K)

  3. Clinical and radiological features of hypertensive brainstem encephalopathy

    Directory of Open Access Journals (Sweden)

    Xiao-qiu LI

    2015-07-01

    Full Text Available Objective To discuss the diagnosis and treatment of hypertensive brainstem encephalopathy. Methods  The clinical and imaging data of 3 cases of hypertensive brainstem encephalopathy were summarized and analyzed for the purpose of improving the acumen in diagnosis and treatment. Results All the 3 patients showed relatively mild clinical symptoms, and they were misdiagnosed in different degrees during the treatment, but their clinical symptoms were improved by rapid and effective antihypertensive therapy. Cerebral CT and MRI scans revealed extensive abnormal signals in brain stem, with or without supratentorial lesions and brain stem hemorrhage. The lesions as revealed by imaging were improved significantly after treatment. Conclusions Clinical-radiographic dissociation is the classic feature of hypertensive brainstem encephalopathy. The clinical symptoms and lesions as shown by imaging could be improved after active treatment. DOI: 10.11855/j.issn.0577-7402.2015.06.03

  4. Convergent input from brainstem coincidence detectors onto delay-sensitive neurons in the inferior colliculus.

    Science.gov (United States)

    McAlpine, D; Jiang, D; Shackleton, T M; Palmer, A R

    1998-08-01

    Responses of low-frequency neurons in the inferior colliculus (IC) of anesthetized guinea pigs were studied with binaural beats to assess their mean best interaural phase (BP) to a range of stimulating frequencies. Phase plots (stimulating frequency vs BP) were produced, from which measures of characteristic delay (CD) and characteristic phase (CP) for each neuron were obtained. The CD provides an estimate of the difference in travel time from each ear to coincidence-detector neurons in the brainstem. The CP indicates the mechanism underpinning the coincidence detector responses. A linear phase plot indicates a single, constant delay between the coincidence-detector inputs from the two ears. In more than half (54 of 90) of the neurons, the phase plot was not linear. We hypothesized that neurons with nonlinear phase plots received convergent input from brainstem coincidence detectors with different CDs. Presentation of a second tone with a fixed, unfavorable delay suppressed the response of one input, linearizing the phase plot and revealing other inputs to be relatively simple coincidence detectors. For some neurons with highly complex phase plots, the suppressor tone altered BP values, but did not resolve the nature of the inputs. For neurons with linear phase plots, the suppressor tone either completely abolished their responses or reduced their discharge rate with no change in BP. By selectively suppressing inputs with a second tone, we are able to reveal the nature of underlying binaural inputs to IC neurons, confirming the hypothesis that the complex phase plots of many IC neurons are a result of convergence from simple brainstem coincidence detectors.

  5. SU-E-E-01: ABR Diagnostic Radiology Core Exam: Was Our Redesigned Physics Course Successful in Teaching Physics to Radiology Residents?

    International Nuclear Information System (INIS)

    Kanal, K; Hoff, M; Dickinson, R; Zamora, D; Stewart, B

    2014-01-01

    Purpose: Our purpose is to evaluate the effectiveness of our two year physics course in preparing radiology residents for the American Board of Radiology (ABR) diagnostic radiology exam. Methods: We designed a new two-year physics course that integrates radiology clinical content and practice and is primarily based on the AAPM curriculum and RSNA/AAPM physics modules. Biweekly classes focus on relevant concepts from assigned reading and use audience response systems to encourage participation. Teaching efficiency is optimized through lecturer rotations of physicists, radiologists, and guest speakers. An emphasis is placed on clinical relevance by requiring lab work and providing equipment demonstrations. Periodic quiz were given during the course. The course website was also redesigned for usability, and physics review lectures were conducted two weeks before the board exam to refresh key concepts. At the completion of our first two-year course, we conducted a confidential evaluation of the faculty and course. The evaluation assessed metrics such as overall organization, clinical relevance of content, and level of difficulty, with a rating scale from poor to excellent. Results: Our evaluation indicated that the redesigned course provided effective board exam preparation, with most responses between good and excellent. There was some criticism on the course length and on chronological discontinuity, but the review lectures were appreciated by the residents. All of our residents passed the physics component of the ABR exam with scores exceeding the minimum passing score by a significant margin. Conclusion: The course evaluation and board exam results indicate that our new two-year course format provides valuable board exam preparation. This is possible thanks to the time and effort taken by the physics faculty on ensuring the residents get quality physics education

  6. Reduced acoustic startle response and peripheral hearing loss in the 5xFAD mouse model of Alzheimer's disease.

    Science.gov (United States)

    O'Leary, T P; Shin, S; Fertan, E; Dingle, R N; Almuklass, A; Gunn, R K; Yu, Z; Wang, J; Brown, R E

    2017-06-01

    Hearing dysfunction has been associated with Alzheimer's disease (AD) in humans, but there is little data on the auditory function of mouse models of AD. Furthermore, characterization of hearing ability in mouse models is needed to ensure that tests of cognition that use auditory stimuli are not confounded by hearing dysfunction. Therefore, we assessed acoustic startle response and pre-pulse inhibition in the double transgenic 5xFAD mouse model of AD from 3-4 to 16 months of age. The 5xFAD mice showed an age-related decline in acoustic startle as early as 3-4 months of age. We subsequently tested auditory brainstem response (ABR) thresholds at 4 and 13-14 months of age using tone bursts at frequencies of 2-32 kHz. The 5xFAD mice showed increased ABR thresholds for tone bursts between 8 and 32 kHz at 13-14 months of age. Finally, cochleae were extracted and basilar membranes were dissected to count hair cell loss across the cochlea. The 5xFAD mice showed significantly greater loss of both inner and outer hair cells at the apical and basal ends of the basilar membrane than wild-type mice at 15-16 months of age. These results indicate that the 5xFAD mouse model of AD shows age-related decreases in acoustic startle responses, which are at least partially due to age-related peripheral hearing loss. Therefore, we caution against the use of cognitive tests that rely on audition in 5xFAD mice over 3-4 months of age, without first confirming that performance is not confounded by hearing dysfunction. © 2017 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  7. Localization of the brainstem GABAergic neurons controlling paradoxical (REM sleep.

    Directory of Open Access Journals (Sweden)

    Emilie Sapin

    Full Text Available Paradoxical sleep (PS is a state characterized by cortical activation, rapid eye movements and muscle atonia. Fifty years after its discovery, the neuronal network responsible for the genesis of PS has been only partially identified. We recently proposed that GABAergic neurons would have a pivotal role in that network. To localize these GABAergic neurons, we combined immunohistochemical detection of Fos with non-radioactive in situ hybridization of GAD67 mRNA (GABA synthesis enzyme in control rats, rats deprived of PS for 72 h and rats allowed to recover after such deprivation. Here we show that GABAergic neurons gating PS (PS-off neurons are principally located in the ventrolateral periaqueductal gray (vlPAG and the dorsal part of the deep mesencephalic reticular nucleus immediately ventral to it (dDpMe. Furthermore, iontophoretic application of muscimol for 20 min in this area in head-restrained rats induced a strong and significant increase in PS quantities compared to saline. In addition, we found a large number of GABAergic PS-on neurons in the vlPAG/dDPMe region and the medullary reticular nuclei known to generate muscle atonia during PS. Finally, we showed that PS-on neurons triggering PS localized in the SLD are not GABAergic. Altogether, our results indicate that multiple populations of PS-on GABAergic neurons are distributed in the brainstem while only one population of PS-off GABAergic neurons localized in the vlPAG/dDpMe region exist. From these results, we propose a revised model for PS control in which GABAergic PS-on and PS-off neurons localized in the vlPAG/dDPMe region play leading roles.

  8. Stance disturbance in multiple sclerosis: brainstem lesions and posturographic assessment

    Directory of Open Access Journals (Sweden)

    Peter Schalek

    2012-01-01

    Full Text Available

    Background. Balance disorders are commonly evidenced during the course of multiple sclerosis (MS. The aim of this study is to report characteristics of MS patient stance control disorders, measured by means of posturography and related to the brainstem lesions.

    Methods. Thirty-eight patients affected by MS, mildly to moderately disable according to Kurtzke’s Expanded Disability Status Scale, underwent a complete clinical neurological and vestibular evaluation and brain MRI scanning. All patients were then tested on a static posturography platform (Tetrax, Israel in four conditions: eyes open and closed standing on a firm surface and on a foam pad.

    Results. Clinical and/or MRI evidence of brainstem involvement was observed in 55.3 % of patients. When brainstem lesion was detected, Fourier analysis showed a typical pattern characterized by inversion of the  0- 0.1 Hz and  0.1 - 0.25 Hz. frequency bands.

    Conclusions. MS leads to pervasive postural disturbances in the majority of subjects, including the visuo-vestibular loops and proprioception involving vestibulo-spinal pathways in at least 55.3 % of patients. Our results may also suggest the presence of Fourier inversion in patients with brainstem lesions.


  9. Intraparenchymal papillary meningioma of brainstem: case report and literature review

    Directory of Open Access Journals (Sweden)

    Jiang Xiao-Bing

    2012-01-01

    Full Text Available Abstract Both intraparenchymal papillary meningioma and papillary meningioma with cyst formation of brainstem have never been reported. The authors present an extremely rare case of patient with intraparenchymal papillary meningioma of brainstem. A 23-year-old Chinese male presented with a 4-month history of progressive left upper limb and facial nerve palsy. Magnetic resonance imaging revealed a cystic-solid, heterogeneously enhancing mass in pons and right cerebral peduncle with no dural attachment. The tumor was totally removed via subtemporal approach. During surgery, the lesion was found to be completely intraparenchymal. Histological and immunohistochemical examinations were compatible with the diagnosis of papillary meningioma. The lesion recurred nine months after primary surgery, a second surgery followed by radiotherapy was performed. Till to now (nearly 2 years after the treatment, the patient is tumor free survival. Intraparenchymal meningioma of brainstem with cystic formation is very rare, however, it should be considered as a differential diagnosis of a brainstem neoplasm. The present case strongly recommended that postoperative radiotherapy was essential for the patients with papillary meningiomas.

  10. Diffuse and focal presentations of brainstem tumors in children: the images and the prognostic value

    International Nuclear Information System (INIS)

    Menor, F.; Canete, A.; Romero, M. J.; Trilles, L.; Carvajal, E.; Marti-Bonmati, L.

    2000-01-01

    To determine whether the presentation of brainstem tumors as diffuse or focal lesions showed any prognostic value in children. A retrospective review was carried out of the neuroradiological findings in 43 children with brainstem tumors, all of whom underwent computed tomography (CT) and 31 of whom underwent magnetic resonance (MR). The diffuse tumors (n=20) were all located in the pons, spreading to mesencephalon in 6 cases and to medulla oblongata in 1, and exhibiting exophytic growth, preferentially to the prepontine cistern. They presented homogeneous low attenuation in CT (90%) and decrease/increased signal intensity in T1/T2-weighted MR images (91.6%). Contrast uptake was observed in 20% of cases, with agreement between CT and MR. The patients showed a good initial response to treatment (70%), a high rate of relapse (80%) and a 5-year survival of 12%. The focal tumors were located in the pons (11 cases, spreading to the medulla oblongata in 2), mesencephalon (11 cases, 9 tectal and 2 peduncular) and medulla oblongata (1 case), and exhibited exophytic growth predominantly to the pontocerebellar junction and to the cerebellar peduncles. They showed a certain tendency toward heterogeneity (21.7%), toward isoattenuation in CT (47.8%) and isointensity in T1-weighted MR images (26.3%). CT showed a rate of tumor uptake of 26%, while the rate of contrast iptake was 58% MR. Fifty percent of these lesions responded well to therapy, with a recurrence rate of 28% and 4-year survival of 63%. Neuroimaging helps to define two basic patterns in brainstem tumors that play a role in prognosis. The diffuse tumor, which characteristically shows a good initial response to therapy, has a worse prognosis, probably reflecting its histological aggressiveness. (Author) 21 refs

  11. Sensitization of trigeminal brainstem pathways in a model for tear deficient dry eye.

    Science.gov (United States)

    Rahman, Mostafeezur; Okamoto, Keiichiro; Thompson, Randall; Katagiri, Ayano; Bereiter, David A

    2015-05-01

    Chronic dry eye disease (DE) is associated with an unstable tear film and symptoms of ocular discomfort. The characteristics of symptoms suggest a key role for central neural processing; however, little is known about central neuroplasticity and DE. We used a model for tear deficient DE and assessed effects on eye blink behavior, orbicularis oculi muscle activity (OOemg), and trigeminal brainstem neural activity in male rats. Ocular-responsive neurons were recorded at the interpolaris/caudalis transition (Vi/Vc) and Vc/upper cervical cord (Vc/C1) regions under isoflurane, whereas OOemg activity was recorded under urethane. Spontaneous tear volume was reduced by ∼50% at 14 days after exorbital gland removal. Hypertonic saline-evoked eye blink behavior in awake rats was enhanced throughout the 14 days after surgery. Saline-evoked neural activity at the Vi/Vc transition and in superficial and deep laminae at the Vc/C1 region was greatly enhanced in DE rats. Neurons from DE rats classified as wide dynamic range displayed enlarged convergent periorbital receptive fields consistent with central sensitization. Saline-evoked OOemg activity was markedly enhanced in DE rats compared with controls. Synaptic blockade at the Vi/Vc transition or the Vc/C1 region greatly reduced hypertonic saline-evoked OOemg activity in DE and sham rats. These results indicated that persistent tear deficiency caused sensitization of ocular-responsive neurons at multiple regions of the caudal trigeminal brainstem and enhanced OOemg activity. Central sensitization of ocular-related brainstem circuits is a significant factor in DE and likely contributes to the apparent weak correlation between peripheral signs of tear dysfunction and symptoms of irritation.

  12. The Structural, Functional and Molecular Organization of the Brainstem

    Directory of Open Access Journals (Sweden)

    Rudolf eNieuwenhuys

    2011-06-01

    Full Text Available According to Wilhelm His (1891, 1893 the brainstem consists of two longitudinal zones, the dorsal alar plate (sensory in nature and the ventral basal plate (motor in nature. Johnston and Herrick indicated that both plates can be subdivided into separate somatic and visceral zones, distinguishing somatosensory and viscerosensory zones within the alar plate, and visceromotor and somatomotor zones within the basal plate. To test the validity of this ‘four-functional-zones’ concept, I developed a topological procedure, surveying the spatial relationships of the various cell masses in the brainstem in a single figure. Brainstems of 16 different anamniote species were analyzed, and revealed that the brainstems are clearly divisible into four morphological zones, which correspond largely with the functional zones of Johnston and Herrick. Exceptions include (1 the magnocellular vestibular nucleus situated in the viscerosensory zone; (2 the basal plate containing a number of evidently non-motor centres (superior and inferior olives. Nevertheless the ‘functional zonal model’ has explanatory value. Thus, it is possible to interpret certain brain specializations related to particular behavioural profiles, as ‘local hypertrophies’ of one or two functional columns. Recent developmental molecular studies on brains of birds and mammals confirmed the presence of longitudinal zones, and also showed molecularly defined transverse bands or neuromeres throughout development. The intersecting boundaries of the longitudinal zones and the transverse bands appeared to delimit radially arranged histogenetic domains. Because neuromeres have been observed in embryonic and larval stages of numerous anamniote species, it may be hypothesized that the brainstems of all vertebrates share a basic organizational plan, in which intersecting longitudinal and transverse zones form fundamental histogenetic and genoarchitectonic units.

  13. Optimization behavior of brainstem respiratory neurons. A cerebral neural network model.

    Science.gov (United States)

    Poon, C S

    1991-01-01

    A recent model of respiratory control suggested that the steady-state respiratory responses to CO2 and exercise may be governed by an optimal control law in the brainstem respiratory neurons. It was not certain, however, whether such complex optimization behavior could be accomplished by a realistic biological neural network. To test this hypothesis, we developed a hybrid computer-neural model in which the dynamics of the lung, brain and other tissue compartments were simulated on a digital computer. Mimicking the "controller" was a human subject who pedalled on a bicycle with varying speed (analog of ventilatory output) with a view to minimize an analog signal of the total cost of breathing (chemical and mechanical) which was computed interactively and displayed on an oscilloscope. In this manner, the visuomotor cortex served as a proxy (homolog) of the brainstem respiratory neurons in the model. Results in 4 subjects showed a linear steady-state ventilatory CO2 response to arterial PCO2 during simulated CO2 inhalation and a nearly isocapnic steady-state response during simulated exercise. Thus, neural optimization is a plausible mechanism for respiratory control during exercise and can be achieved by a neural network with cognitive computational ability without the need for an exercise stimulus.

  14. Detection of Perinatal Cytomegalovirus Infection and Sensorineural Hearing Loss in Belgian Infants by Measurement of Automated Auditory Brainstem Response▿

    OpenAIRE

    Verbeeck, Jannick; Van Kerschaver, Erwin; Wollants, Elke; Beuselinck, Kurt; Stappaerts, Luc; Van Ranst, Marc

    2008-01-01

    Since auditory disability causes serious problems in the development of speech and in the total development of a child, it is crucial to diagnose possible hearing impairment as soon as possible after birth. This study evaluates the neonatal hearing screening program in Flanders, Belgium. The auditory ability of 118,438 babies was tested using the automated auditory brainstem response. We selected 194 babies with indicative hearing impairment and 332 matched controls to investigate the associa...

  15. [Research on Cultivation and Stability of Nitritation Granular Sludge in Integrated ABR-CSTR Reactor].

    Science.gov (United States)

    Wu, Kai-cheng; Wu, Peng; Shen, Yao-liang; Li, Yue-han; Wang, Han-fang; Xu, Yue-zhong

    2015-11-01

    Abstract: The last two compartments of the Anaerobic Baffled Readtor ( ABR) were altered into aeration tank and sedimentation tank respectively to get an integrated anaerobic-aerobic reactor, using anaerobic granular sludge in anaerobic zone and aerobic granular sludge in aerobic zone as seed sludge. The research explored the condition to cultivate nitritation granular sludge, under the condition of continuous flow. The C/N rate was decreased from 1 to 0.4 and the ammonia nitrogen volumetric loading rate was increased from 0.89 kg x ( m3 x d)(-1) to 2.23 kg x (m3 x d)(-1) while the setting time of 1 h was controlled in the aerobic zone. After the system was operated for 45 days, the mature nitritation granular sludge in aerobic zone showed a compact structure and yellow color while the nitrite accumulation rate was about 80% in the effluent. The associated inhibition of free ammonia (FA) and free nitrous acid (FNA) dominated the nitritation. Part of granules lost stability during the initial period of operation and flocs appeared in the aerobic zone. However, the flocs were transformed into newly generated small particles in the following reactor operation, demonstrating that organic carbon was benefit to granulation and the enrichment of slow-growing nitrifying played an important role in the stability of granules.

  16. Ethnobotany, chemical constituents and biological activities of the flowers of Hydnora abyssinica A.Br. (Hydnoraceae).

    Science.gov (United States)

    Al-Fatimi, M; Ali, N A A; Kilian, N; Franke, K; Arnold, N; Kuhnt, C; Schmidt, J; Lindequist, U

    2016-04-01

    Hydnora abyssinica A.Br. (Hydnoraceae), a holoparasitic herb, is for the first time recorded for Abyan governorate of South Yemen. Flowers of this species were studied for their ethnobotanical, biological and chemical properties for the first time. In South Yemen, they are traditionally used as wild food and to cure stomach diseases, gastric ulcer and cancer. Phytochemical analysis of the extracts showed the presence of terpenes, tannins, phenols, and flavonoids. The volatile components of the air-dried powdered flowers were identified using a static headspace GC/MS analysis as acetic acid, ethyl acetate, sabinene, α-terpinene, (+)-D-limonene and γ-terpinene. These volatile compounds that characterize the odor and taste of the flowers were detected for the first time in a species of the family Hydnoraceae. The flowers were extracted by n-hexane, dichlormethane, ethyl acetate, ethanol, methanol and water. With exception of the water extract all extracts demonstrated activities against Gram-positive bacteria as well as remarkable radical scavenging activities in DPPH assay. Ethyl acetate, methanol and water extracts exhibited good antifungal activities. The cytotoxic activity of the extracts against FL cells, measured in neutral red assay, was only weak (IC50 > 500 μg/mL). The results justify the traditional use of the flowers of Hydnora abyssinica in South Yemen.

  17. Medical Physics Residency Consortium: collaborative endeavors to meet the ABR 2014 certification requirements

    Science.gov (United States)

    Parker, Brent C.; Duhon, John; Yang, Claus C.; Wu, H. Terry; Hogstrom, Kenneth R.

    2014-01-01

    In 2009, Mary Bird Perkins Cancer Center (MBPCC) established a Radiation Oncology Physics Residency Program to provide opportunities for medical physics residency training to MS and PhD graduates of the CAMPEP‐accredited Louisiana State University (LSU)‐MBPCC Medical Physics Graduate Program. The LSU‐MBPCC Program graduates approximately six students yearly, which equates to a need for up to twelve residency positions in a two‐year program. To address this need for residency positions, MBPCC has expanded its Program by developing a Consortium consisting of partnerships with medical physics groups located at other nearby clinical institutions. The consortium model offers the residents exposure to a broader range of procedures, technology, and faculty than available at the individual institutions. The Consortium institutions have shown a great deal of support from their medical physics groups and administrations in developing these partnerships. Details of these partnerships are specified within affiliation agreements between MBPCC and each participating institution. All partner sites began resident training in 2011. The Consortium is a network of for‐profit, nonprofit, academic, community, and private entities. We feel that these types of collaborative endeavors will be required nationally to reach the number of residency positions needed to meet the 2014 ABR certification requirements and to maintain graduate medical physics training programs. PACS numbers: 01.40.Fk, 01.40.gb PMID:24710434

  18. Chronic exposure to hypergravity affects thyrotropin-releasing hormone levels in rat brainstem and cerebellum

    Science.gov (United States)

    Daunton, N. G.; Tang, F.; Corcoran, M. L.; Fox, R. A.; Man, S. Y.

    1998-01-01

    In studies to determine the neurochemical mechanisms underlying adaptation to altered gravity we have investigated changes in neuropeptide levels in brainstem, cerebellum, hypothalamus, striatum, hippocampus, and cerebral cortex by radioimmunoassay. Fourteen days of hypergravity (hyperG) exposure resulted in significant increases in thyrotropin-releasing hormone (TRH) content of brainstem and cerebellum, but no changes in levels of other neuropeptides (beta-endorphin, cholecystokinin, met-enkephalin, somatostatin, and substance P) examined in these areas were found, nor were TRH levels significantly changed in any other brain regions investigated. The increase in TRH in brainstem and cerebellum was not seen in animals exposed only to the rotational component of centrifugation, suggesting that this increase was elicited by the alteration in the gravitational environment. The only other neuropeptide affected by chronic hyperG exposure was met-enkephalin, which was significantly decreased in the cerebral cortex. However, this alteration in met-enkephalin was found in both hyperG and rotation control animals and thus may be due to the rotational rather than the hyperG component of centrifugation. Thus it does not appear as if there is a generalized neuropeptide response to chronic hyperG following 2 weeks of exposure. Rather, there is an increase only of TRH and that occurs only in areas of the brain known to be heavily involved with vestibular inputs and motor control (both voluntary and autonomic). These results suggest that TRH may play a role in adaptation to altered gravity as it does in adaptation to altered vestibular input following labyrinthectomy, and in cerebellar and vestibular control of locomotion, as seen in studies of ataxia.

  19. Two-phase anaerobic digestion for biogas production from dairy effluent—CSTR and ABR in series

    DEFF Research Database (Denmark)

    Jürgensen, L.; Ehimen, E. A.; Born, J.

    2016-01-01

    Anaerobic digestion of low-strength dairy waste water has been used for the production of biogas. A two-phase pilot scale process had been established within 90 d using a 1 m3continuous stirred tank reactor (CSTR) and a 200 l anaerobic baffled reactor (ABR) in series. The system was fed at constant...... retention time of 1.6 d and with changing feed strengths resulting in various organic loading rates between 1.25-4.50 g/(l d). The average COD removal was 82% with a biogas yield of 0.26 l/gCOD. The combination of CSTR and ABR overcame the disadvantages of both reactor types. By further optimization...

  20. The startup performance and microbial distribution of an anaerobic baffled reactor (ABR) treating medium-strength synthetic industrial wastewater.

    Science.gov (United States)

    Jiang, Hao; Nie, Hong; Ding, Jiangtao; Stinner, Walter; Sun, Kaixuan; Zhou, Hongjun

    2018-01-02

    In this study, an anaerobic baffled reactor (ABR) with seven chambers was applied to treat medium-strength synthetic industrial wastewater (MSIW). The performance of startup and shock test on treating MSIW was investigated. During the acclimation process, the chemical oxygen demand (COD) of MSIW gradually increased from 0 to 2,000 mg L -1 , and the COD removal finally reached 90%. At shock test, the feeding COD concentration increased by one-fifth and the reactor adapted very well with a COD removal of 82%. In a stable state, Comamonas, Smithella, Syntrophomonas and Pseudomonas were the main populations of bacteria, while the predominant methanogen was Methanobacterium. The results of chemical and microbiological analysis indicated the significant advantages of ABR, including buffering shocks, separating stages with matching microorganisms and promoting syntrophism. Meanwhile, the strategies for acclimation and operation were of great importance. Further work can test reactor performance in the treatment of actual industrial wastewater.

  1. Diffusion tensor imaging of the brainstem in children with achondroplasia.

    Science.gov (United States)

    Bosemani, Thangamadhan; Orman, Gunes; Carson, Kathryn A; Meoded, Avner; Huisman, Thierry A G M; Poretti, Andrea

    2014-11-01

    The aims of this study were to compare, using diffusion tensor imaging (DTI) of the brainstem, microstructural integrity of the white matter in children with achondroplasia and age-matched participants and to correlate the severity of craniocervical junction (CCJ) narrowing and neurological findings with DTI scalars in children with achondroplasia. This study also aimed to assess the potential role of fibroblast growth factor receptor type 3 on white matter microstructure. Diffusion tensor imaging was performed using a 1.5T magnetic resonance scanner and balanced pairs of diffusion gradients along 20 non-collinear directions. Measurements were obtained from regions of interest, sampled in each pontine corticospinal tract (CST), medial lemniscus, and middle cerebellar peduncle, as well as in the lower brainstem and centrum semiovale, for fractional anisotropy and for mean, axial, and radial diffusivity. In addition, a severity score for achondroplasia was assessed by measuring CCJ narrowing. Eight patients with achondroplasia (seven males, one female; mean age 5y 6mo, range 1y 1mo-15y 1mo) and eight age- and sex-matched comparison participants (mean age 5y 2mo, range 1y 1mo-14y 11mo) were included in this study. Fractional anisotropy was lower and mean diffusivity and radial diffusivity were higher in the lower brainstem of patients with achondroplasia than in age-matched comparison participants. The CST and middle cerebellar peduncle of the participants showed increases in mean, axial, and radial diffusivity. Fractional anisotropy in the lower brainstem was negatively correlated with the degree of CCJ narrowing. No differences in the DTI metrics of the centrum semiovale were observed between the two groups. The reduction in fractional anisotropy and increase in diffusivities in the lower brainstem of participants with achondroplasia may reflect secondary encephalomalacic degeneration and cavitation of the affected white matter tracts as shown by histology. In

  2. Enhanced Excitatory Connectivity and Disturbed Sound Processing in the Auditory Brainstem of Fragile X Mice.

    Science.gov (United States)

    Garcia-Pino, Elisabet; Gessele, Nikodemus; Koch, Ursula

    2017-08-02

    Hypersensitivity to sounds is one of the prevalent symptoms in individuals with Fragile X syndrome (FXS). It manifests behaviorally early during development and is often used as a landmark for treatment efficacy. However, the physiological mechanisms and circuit-level alterations underlying this aberrant behavior remain poorly understood. Using the mouse model of FXS ( Fmr1 KO ), we demonstrate that functional maturation of auditory brainstem synapses is impaired in FXS. Fmr1 KO mice showed a greatly enhanced excitatory synaptic input strength in neurons of the lateral superior olive (LSO), a prominent auditory brainstem nucleus, which integrates ipsilateral excitation and contralateral inhibition to compute interaural level differences. Conversely, the glycinergic, inhibitory input properties remained unaffected. The enhanced excitation was the result of an increased number of cochlear nucleus fibers converging onto one LSO neuron, without changing individual synapse properties. Concomitantly, immunolabeling of excitatory ending markers revealed an increase in the immunolabeled area, supporting abnormally elevated excitatory input numbers. Intrinsic firing properties were only slightly enhanced. In line with the disturbed development of LSO circuitry, auditory processing was also affected in adult Fmr1 KO mice as shown with single-unit recordings of LSO neurons. These processing deficits manifested as an increase in firing rate, a broadening of the frequency response area, and a shift in the interaural level difference function of LSO neurons. Our results suggest that this aberrant synaptic development of auditory brainstem circuits might be a major underlying cause of the auditory processing deficits in FXS. SIGNIFICANCE STATEMENT Fragile X Syndrome (FXS) is the most common inheritable form of intellectual impairment, including autism. A core symptom of FXS is extreme sensitivity to loud sounds. This is one reason why individuals with FXS tend to avoid social

  3. Mosaic Evolution of Brainstem Motor Nuclei in Catarrhine Primates

    Directory of Open Access Journals (Sweden)

    Seth D. Dobson

    2011-01-01

    Full Text Available Facial motor nucleus volume coevolves with both social group size and primary visual cortex volume in catarrhine primates as part of a specialized neuroethological system for communication using facial expressions. Here, we examine whether facial nucleus volume also coevolves with functionally unrelated brainstem motor nuclei (trigeminal motor and hypoglossal due to developmental constraints. Using phylogenetically informed multiple regression analyses of previously published brain component data, we demonstrate that facial nucleus volume is not correlated with the volume of other motor nuclei after controlling for medulla volume. Our results show that brainstem motor nuclei can evolve independently of other developmentally linked structures in association with specific behavioral ecological conditions. This finding provides additional support for the mosaic view of brain evolution.

  4. SU-E-E-02: An Excel-Based Study Tool for ABR-Style Exams

    International Nuclear Information System (INIS)

    Cline, K; Stanley, D; Defoor, D; Stathakis, S; Gutierrez, A; Papanikolaou, N; Kirby, N

    2015-01-01

    Purpose: As the landscape of learning and testing shifts toward a computer-based environment, a replacement for paper-based methods of studying is desirable. Using Microsoft Excel, a study tool was developed that allows the user to populate multiple-choice questions and then generate an interactive quiz session to answer them. Methods: The code for the tool was written using Microsoft Excel Visual Basic for Applications with the intent that this tool could be implemented by any institution with Excel. The base tool is a template with a setup macro, which builds out the structure based on user’s input. Once the framework is built, the user can input sets of multiple-choice questions, answer choices, and even add figures. The tool can be run in random-question or sequential-question mode for single or multiple courses of study. The interactive session allows the user to select answer choices and immediate feedback is provided. Once the user is finished studying, the tool records the day’s progress by reporting progress statistics useful for trending. Results: Six doctoral students at UTHSCSA have used this tool for the past two months to study for their qualifying exam, which is similar in format and content to the American Board of Radiology (ABR) Therapeutic Part II exam. The students collaborated to create a repository of questions, met weekly to go over these questions, and then used the tool to prepare for their exam. Conclusion: The study tool has provided an effective and efficient way for students to collaborate and be held accountable for exam preparation. The ease of use and familiarity of Excel are important factors for the tool’s use. There are software packages to create similar question banks, but this study tool has no additional cost for those that already have Excel. The study tool will be made openly available

  5. SU-E-E-02: An Excel-Based Study Tool for ABR-Style Exams

    Energy Technology Data Exchange (ETDEWEB)

    Cline, K; Stanley, D; Defoor, D; Stathakis, S; Gutierrez, A; Papanikolaou, N; Kirby, N [University of Texas Health Science Center at San Antonio, Cancer Therapy and Research Center, San Antonio, TX (United States)

    2015-06-15

    Purpose: As the landscape of learning and testing shifts toward a computer-based environment, a replacement for paper-based methods of studying is desirable. Using Microsoft Excel, a study tool was developed that allows the user to populate multiple-choice questions and then generate an interactive quiz session to answer them. Methods: The code for the tool was written using Microsoft Excel Visual Basic for Applications with the intent that this tool could be implemented by any institution with Excel. The base tool is a template with a setup macro, which builds out the structure based on user’s input. Once the framework is built, the user can input sets of multiple-choice questions, answer choices, and even add figures. The tool can be run in random-question or sequential-question mode for single or multiple courses of study. The interactive session allows the user to select answer choices and immediate feedback is provided. Once the user is finished studying, the tool records the day’s progress by reporting progress statistics useful for trending. Results: Six doctoral students at UTHSCSA have used this tool for the past two months to study for their qualifying exam, which is similar in format and content to the American Board of Radiology (ABR) Therapeutic Part II exam. The students collaborated to create a repository of questions, met weekly to go over these questions, and then used the tool to prepare for their exam. Conclusion: The study tool has provided an effective and efficient way for students to collaborate and be held accountable for exam preparation. The ease of use and familiarity of Excel are important factors for the tool’s use. There are software packages to create similar question banks, but this study tool has no additional cost for those that already have Excel. The study tool will be made openly available.

  6. Thalamic, brainstem, and cerebellar glucose metabolism in the hemiplegic monkey

    Energy Technology Data Exchange (ETDEWEB)

    Shimoyama, I.; Dauth, G.W.; Gilman, S.; Frey, K.A.; Penney, J.B. Jr.

    1988-12-01

    Unilateral ablation of cerebral cortical areas 4 and 6 of Brodmann in the macaque monkey results in a contralateral hemiplegia that resolves partially with time. During the phase of dense hemiplegia, local cerebral metabolic rate for glucose (1CMRG1c) is decreased significantly in most of the thalamic nuclei ipsilateral to the ablation, and there are slight contralateral decreases. The lCMRGlc is reduced bilaterally in most of the brainstem nuclei and bilaterally in the deep cerebellar nuclei, but only in the contralateral cerebellar cortex. During the phase of partial motor recovery, lCMRGlc is incompletely restored in many of the thalamic nuclei ipsilateral to the ablation and completely restored in the contralateral nuclei. In the brainstem and deep cerebellar nuclei, poor to moderate recovery occurs bilaterally. Moderate recovery occurs in the contralateral cerebellar cortex. The findings demonstrate that a unilateral cerebral cortical lesion strongly affects lCMRGlc in the thalamus ipsilaterally and in the cerebellar cortex contralaterally, but in the brainstem bilaterally. Partial recovery of lCMRGlc accompanies the progressive motor recovery. The structures affected include those with direct, and also those with indirect, connections to the areas ablated.

  7. Comprehensive evaluation of a child with an auditory brainstem implant.

    Science.gov (United States)

    Eisenberg, Laurie S; Johnson, Karen C; Martinez, Amy S; DesJardin, Jean L; Stika, Carren J; Dzubak, Danielle; Mahalak, Mandy Lutz; Rector, Emily P

    2008-02-01

    We had an opportunity to evaluate an American child whose family traveled to Italy to receive an auditory brainstem implant (ABI). The goal of this evaluation was to obtain insight into possible benefits derived from the ABI and to begin developing assessment protocols for pediatric clinical trials. Case study. Tertiary referral center. Pediatric ABI Patient 1 was born with auditory nerve agenesis. Auditory brainstem implant surgery was performed in December, 2005, in Verona, Italy. The child was assessed at the House Ear Institute, Los Angeles, in July 2006 at the age of 3 years 11 months. Follow-up assessment has continued at the HEAR Center in Birmingham, Alabama. Auditory brainstem implant. Performance was assessed for the domains of audition, speech and language, intelligence and behavior, quality of life, and parental factors. Patient 1 demonstrated detection of sound, speech pattern perception with visual cues, and inconsistent auditory-only vowel discrimination. Language age with signs was approximately 2 years, and vocalizations were increasing. Of normal intelligence, he exhibited attention deficits with difficulty completing structured tasks. Twelve months later, this child was able to identify speech patterns consistently; closed-set word identification was emerging. These results were within the range of performance for a small sample of similarly aged pediatric cochlear implant users. Pediatric ABI assessment with a group of well-selected children is needed to examine risk versus benefit in this population and to analyze whether open-set speech recognition is achievable.

  8. Effect of edaravone on acute brainstem-cerebellar infarction with vertigo and sudden hearing loss.

    Science.gov (United States)

    Inoue, Yuta; Yabe, Takao; Okada, Kazunari; Nakamura, Yuka

    2014-06-01

    We report 2 cases with acute brainstem and brainstem-cerebellar infarction showed improvement of their signs and symptoms after administration of edaravone. Case 1, a 74-year-old woman who experienced sudden vertigo, also had dysarthria and left hemiplegia. Magnetic resonance imaging (MRI) showed an abnormal region in the right ventrolateral medulla oblongata. The patient's vertigo and hemiplegia improved completely after treatment. Case 2, a 50-year-old man who experienced sudden vertigo and sensorineural hearing loss (SNHL), developed dysarthria after admission. MRI revealed acute infarction in the right cerebellar hemisphere. Magnetic resonance angiography revealed dissection of the basilar artery and occlusion of the right anterior inferior cerebellar artery. The patient's vertigo and hearing remarkably improved. We have described 2 patients whose early symptoms were vertigo and sudden SNHL, but who were later shown to have ischemic lesions of the central nervous system. Edaravone is neuroprotective drug with free radical-scavenging actions. Free radicals in the ear are responsible for ischemic damage. Edaravone, a free radical scavenger, may be useful in the treatment of vertigo and SNHL. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Effects of myelin or cell body brainstem lesions on 3-channel Lissajous' trajectories of feline auditory brainstem evoked potentials

    OpenAIRE

    Pratt, H; Zaaroor, M; Bleich, N; Starr, A

    1991-01-01

    Auditory brainstem evoked potentials (ABEP) were recorded from 16 awake cats to obtain 3-Channel Lissajous' Trajectories (3CLTs) using three orthogonal differential electrode configurations (nasion - midline nuchal ridge, left - right mastoids, vertex - midline under the mandible). Potentials, evoked by monaural 80 dBnHL (re. human threshold) clicks, were studied before, and up to 7 weeks after inducing neuronal lesions localized to the cochlear nucleus (CN) or the superior olivary complex (S...

  10. Physiological Characterization of Vestibular Efferent Brainstem Neurons Using a Transgenic Mouse Model

    Science.gov (United States)

    Leijon, Sara; Magnusson, Anna K.

    2014-01-01

    The functional role of efferent innervation of the vestibular end-organs in the inner ear remains elusive. This study provides the first physiological characterization of the cholinergic vestibular efferent (VE) neurons in the brainstem by utilizing a transgenic mouse model, expressing eGFP under a choline-acetyltransferase (ChAT)-locus spanning promoter in combination with targeted patch clamp recordings. The intrinsic electrical properties of the eGFP-positive VE neurons were compared to the properties of the lateral olivocochlear (LOC) brainstem neurons, which gives rise to efferent innervation of the cochlea. Both VE and the LOC neurons were marked by their negative resting membrane potential neurons differed significantly in the depolarizing range. When injected with positive currents, VE neurons fired action potentials faithfully to the onset of depolarization followed by sparse firing with long inter-spike intervals. This response gave rise to a low response gain. The LOC neurons, conversely, responded with a characteristic delayed tonic firing upon depolarizing stimuli, giving rise to higher response gain than the VE neurons. Depolarization triggered large TEA insensitive outward currents with fast inactivation kinetics, indicating A-type potassium currents, in both the inner ear-projecting neuronal types. Immunohistochemistry confirmed expression of Kv4.3 and 4.2 ion channel subunits in both the VE and LOC neurons. The difference in spiking responses to depolarization is related to a two-fold impact of these transient outward currents on somatic integration in the LOC neurons compared to in VE neurons. It is speculated that the physiological properties of the VE neurons might be compatible with a wide-spread control over motion and gravity sensation in the inner ear, providing likewise feed-back amplification of abrupt and strong phasic signals from the semi-circular canals and of tonic signals from the gravito-sensitive macular organs. PMID:24867596

  11. Evidence that BDNF regulates heart rate by a mechanism involving increased brainstem parasympathetic neuron excitability

    OpenAIRE

    Wan, Ruiqian; Weigand, Letitia A.; Bateman, Ryan; Griffioen, Kathleen; Mendelowitz, David; Mattson, Mark P.

    2014-01-01

    Autonomic control of heart rate is mediated by cardioinhibitory parasympathetic cholinergic neurons located in the brainstem and stimulatory sympathetic noradrenergic neurons. During embryonic development the survival and cholinergic phenotype of brainstem autonomic neurons is promoted by brain-derived neurotrophic factor (BDNF). We now provide evidence that BDNF regulates heart rate by a mechanism involving increased brainstem cardioinhibitory parasympathetic activity. Mice with a BDNF haplo...

  12. Intrinsic brainstem schwannoma – A rare clinical entity and a histological enigma

    Directory of Open Access Journals (Sweden)

    Anil Kumar Sharma

    2016-01-01

    Full Text Available Intraparenchymal schwannomas arising in the brainstem are very rare, and only eight cases have been reported in literature till now. We report an intraparenchymal brainstem schwannoma presenting with the classical clinical presentation of an intrinsic brainstem lesion, and discuss its clinicoradiological characteristics and histological origins. We highlight the importance of an intraoperative frozen section diagnosis in such cases. Intraoperative tissue diagnosis significantly may alter the surgical strategy, which should be aimed at near total intracapsular decompression of the schwannoma.

  13. Process evaluation of the health education resource Abre los Ojos for street-involved youth in Medellín

    Directory of Open Access Journals (Sweden)

    John L. Wylie

    2012-02-01

    Full Text Available Objective: Conduct a process evaluation of a health education resource (pamphlet¸ Abre los Ojos, designed for street-involved youth in Medellín. The primary foci of the evaluation were the process of developing the resource and youth’s subsequent perception of the resource. Methodology: Drawing upon both qualitative and quantitative data, a process evaluation was undertaken. Ninety four street-involved youth between the ages of 14–24 years completed surveys about the resource. These semi-structured interviews were key for the information about youth perception of the resource. In addition to individual interviews, prior to resource creation, a series of focus groups were integral for the development of the resource. Results: The process of consulting with the target population through the focus groups was effective in obtaining their ideas and feedback about what type of content they would like to see in a health education resource, and how they wanted that content presented. After distribution, participants described that Abre los Ojos contained information that was valuable and relevant to their experiences. While not a primary focus of this evaluation, the individual interviews were also able to provide some preliminary insight into whether Abre los Ojos was an effective means for participants to increase their knowledge of content included in the resource. Conclusion: The collaborative process of jointly developing the resource content in partnership with the youth proved very worthwhile. While our research team chose to include information about HIV, through focus group dialogue, the youth themselves determined the additional content themes (piercings, use of solvents, and description of life on the street. The resulting resource was well-received by members of the street-involved population who had not been involved in its design.

  14. Non-homeostatic body weight regulation through a brainstem-restricted receptor for GDF15

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Jer-Yuan; Crawley, Suzanne; Chen, Michael; Ayupova, Dina A.; Lindhout, Darrin A.; Higbee, Jared; Kutach, Alan; Joo, William; Gao, Zhengyu; Fu, Diana; To, Carmen; Mondal, Kalyani; Li, Betty; Kekatpure, Avantika; Wang, Marilyn; Laird, Teresa; Horner, Geoffrey; Chan, Jackie; McEntee, Michele; Lopez, Manuel; Lakshminarasimhan, Damodharan; White, Andre; Wang, Sheng-Ping; Yao, Jun; Yie, Junming; Matern, Hugo; Solloway, Mark; Haldankar, Raj; Parsons, Thomas; Tang, Jie; Shen, Wenyan D.; Alice Chen, Yu; Tian, Hui; Allan, Bernard B.

    2017-09-27

    Under homeostatic conditions, animals use well-defined hypothalamic neural circuits to help maintain stable body weight, by integrating metabolic and hormonal signals from the periphery to balance food consumption and energy expenditure1,2. In stressed or disease conditions, however, animals use alternative neuronal pathways to adapt to the metabolic challenges of altered energy demand3. Recent studies have identified brain areas outside the hypothalamus that are activated under these ‘non-homeostatic’ conditions4,5,6, but the molecular nature of the peripheral signals and brain-localized receptors that activate these circuits remains elusive. Here we identify glial cell-derived neurotrophic factor (GDNF) receptor alpha-like (GFRAL) as a brainstem-restricted receptor for growth and differentiation factor 15 (GDF15). GDF15 regulates food intake, energy expenditure and body weight in response to metabolic and toxin-induced stresses; we show that Gfral knockout mice are hyperphagic under stressed conditions and are resistant to chemotherapy-induced anorexia and body weight loss. GDF15 activates GFRAL-expressing neurons localized exclusively in the area postrema and nucleus tractus solitarius of the mouse brainstem. It then triggers the activation of neurons localized within the parabrachial nucleus and central amygdala, which constitute part of the ‘emergency circuit’ that shapes feeding responses to stressful conditions7. GDF15 levels increase in response to tissue stress and injury, and elevated levels are associated with body weight loss in numerous chronic human diseases8,9. By isolating GFRAL as the receptor for GDF15-induced anorexia and weight loss, we identify a mechanistic basis for the non-homeostatic regulation of neural circuitry by a peripheral signal associated with tissue damage and stress. These findings provide opportunities to develop therapeutic agents for the treatment of disorders with altered energy demand.

  15. LANGUAGE EXPERIENCE SHAPES PROCESSING OF PITCH RELEVANT INFORMATION IN THE HUMAN BRAINSTEM AND AUDITORY CORTEX: ELECTROPHYSIOLOGICAL EVIDENCE.

    Science.gov (United States)

    Krishnan, Ananthanarayan; Gandour, Jackson T

    2014-12-01

    -term experience shapes this adaptive process wherein the top-down connections provide selective gating of inputs to both cortical and subcortical structures to enhance neural responses to specific behaviorally-relevant attributes of the stimulus. A theoretical framework for a neural network is proposed involving coordination between local, feedforward, and feedback components that can account for experience-dependent enhancement of pitch representations at multiple levels of the auditory pathway. The ability to record brainstem and cortical pitch relevant responses concurrently may provide a new window to evaluate the online interplay between feedback, feedforward, and local intrinsic components in the hierarchical processing of pitch relevant information.

  16. Herpes simplex encephalitis with thalamic, brainstem and cerebellar involvement.

    Science.gov (United States)

    Garg, Meenal; Kulkarni, Shilpa; Udwadia Hegde, Anaita

    2018-04-01

    Herpes simplex virus encephalitis is a common and treatable cause of acute encephalitis in all age groups. Certain radiological features such as temporal parenchymal involvement facilitate the diagnosis. The use of herpes simplex virus polymerase chain reaction has expanded the clinical and imaging spectrum. We report the case of a young patient who presented with a movement disorder and predominant involvement of thalami, brainstem and cerebellum on magnetic resonance imaging, and was diagnosed with herpes simplex virus encephalitis. Differentiation from Japanese encephalitis may be difficult in these patients, especially in endemic areas, and may necessitate the use of relevant investigations in all patients.

  17. Descending Command Neurons in the Brainstem that Halt Locomotion

    DEFF Research Database (Denmark)

    Bouvier, Julien; Caggiano, Vittorio; Leiras, Roberto

    2015-01-01

    identifiable brainstem populations to a potential locomotor stop signal, we used developmental genetics and considered a discrete neuronal population in the reticular formation: the V2a neurons. We find that those neurons constitute a major excitatory pathway to locomotor areas of the ventral spinal cord....... Selective activation of V2a neurons of the rostral medulla stops ongoing locomotor activity, owing to an inhibition of premotor locomotor networks in the spinal cord. Moreover, inactivation of such neurons decreases spontaneous stopping in vivo. Therefore, the V2a "stop neurons" represent a glutamatergic...

  18. Brainstem and limbic encephalitis with paraneoplastic neuromyelitis optica.

    Science.gov (United States)

    Moussawi, Khaled; Lin, David J; Matiello, Marcelo; Chew, Sheena; Morganstern, Daniel; Vaitkevicius, Henrikas

    2016-01-01

    The spectrum of disorders associated with anti-neuromyelitis optica (NMO) antibody is being extended to include infrequent instances associated with cancer. We describe a patient with brainstem and limbic encephalitis from NMO-immunoglobulin G in serum and cerebrospinal fluid in the context of newly diagnosed breast cancer. The neurological features markedly improved with excision of her breast cancer and immune suppressive therapy. This case further broadens the NMO spectrum disorders (NMOSD) by an association between NMOSD and cancer and raises the question of coincidental occurrence and the appropriate circumstances to search for a tumor in certain instances of NMO. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Transactivation of the Brassica napus napin promoter by ABI3 requires interaction of the conserved B2 and B3 domains of ABI3 with different cis-elements: B2 mediates activation through an ABRE, whereas B3 interacts with an RY/G-box.

    Science.gov (United States)

    Ezcurra, I; Wycliffe, P; Nehlin, L; Ellerström, M; Rask, L

    2000-10-01

    The transcriptional activator ABI3 is a key regulator of gene expression during embryo maturation in crucifers. In monocots, the related VP1 protein regulates the Em promoter synergistically with abscisic acid (ABA). We identified cis-elements in the Brassica napus napin napA promoter mediating regulation by ABI3 and ABA, by analyzing substitution mutation constructs of napA in transgenic tobacco plantlets ectopically expressing ABI3. In transient analysis using particle bombardment of tobacco leaf sections, a tetramer of the distB ABRE (abscisic acid-responsive element) mediated transactivation by ABI3 and ABI3-dependent response to ABA, whereas a tetramer of the composite RY/G complex, containing RY repeats and a G-box, mediated only ABA-independent transactivation by ABI3. Deletion of the conserved B2 and B3 domains of ABI3 abolished transactivation of napA by ABI3. The two domains of ABI3 interact with different cis-elements: B2 is necessary for ABA-independent and ABA-dependent activations through the distB ABRE, whereas B3 interacts with the RY/G complex. Thus B2 mediates the interaction of ABI3 with the protein complex at the ABRE. The regulation of napA by ABI3 differs from Em regulation by VP1, in that the B3 domain of ABI3 is essential for the ABA-dependent regulation of napA.

  20. Brain-stem evoked potentials and noise effects in seagulls.

    Science.gov (United States)

    Counter, S A

    1985-01-01

    Brain-stem auditory evoked potentials (BAEP) recorded from the seagull were large-amplitude, short-latency, vertex-positive deflections which originate in the eighth nerve and several brain-stem nuclei. BAEP waveforms were similar in latency and configurations to that reported for certain other lower vertebrates and some mammals. BAEP recorded at several pure tone frequencies throughout the seagull's auditory spectrum showed an area of heightened auditory sensitivity between 1 and 3 kHz. This range was also found to be the primary bandwidth of the vocalization output of young seagulls. Masking by white noise and pure tones had remarkable effects on several parameters of the BAEP. In general, the tone- and click-induced BAEP were either reduced or obliterated by both pure tone and white noise maskers of specific signal to noise ratios and high intensity levels. The masking effects observed in this study may be related to the manner in which seagulls respond to intense environmental noise. One possible conclusion is that intense environmental noise, such as aircraft engine noise, may severely alter the seagull's localization apparatus and induce sonogenic stress, both of which could cause collisions with low-flying aircraft.

  1. Dopamine and the Brainstem Locomotor Networks: From Lamprey to Human

    Directory of Open Access Journals (Sweden)

    Dimitri Ryczko

    2017-05-01

    Full Text Available In vertebrates, dopamine neurons are classically known to modulate locomotion via their ascending projections to the basal ganglia that project to brainstem locomotor networks. An increased dopaminergic tone is associated with increase in locomotor activity. In pathological conditions where dopamine cells are lost, such as in Parkinson's disease, locomotor deficits are traditionally associated with the reduced ascending dopaminergic input to the basal ganglia. However, a descending dopaminergic pathway originating from the substantia nigra pars compacta was recently discovered. It innervates the mesencephalic locomotor region (MLR from basal vertebrates to mammals. This pathway was shown to increase locomotor output in lampreys, and could very well play an important role in mammals. Here, we provide a detailed account on the newly found dopaminergic pathway in lamprey, salamander, rat, monkey, and human. In lampreys and salamanders, dopamine release in the MLR is associated with the activation of reticulospinal neurons that carry the locomotor command to the spinal cord. Dopamine release in the MLR potentiates locomotor movements through a D1-receptor mechanism in lampreys. In rats, stimulation of the substantia nigra pars compacta elicited dopamine release in the pedunculopontine nucleus, a known part of the MLR. In a monkey model of Parkinson's disease, a reduced dopaminergic innervation of the brainstem locomotor networks was reported. Dopaminergic fibers are also present in human pedunculopontine nucleus. We discuss the conserved locomotor role of this pathway from lamprey to mammals, and the hypothesis that this pathway could play a role in the locomotor deficits reported in Parkinson's disease.

  2. Clinical analysis of the outcome of patients with brainstem hemorrhage

    International Nuclear Information System (INIS)

    Arimoto, Hirohiko; Takasato, Yoshio; Masaoka, Hiroyuki

    2008-01-01

    To identify prognostic factors in patients with brainstem hemorrhage, we analyzed their clinical symptoms and laboratory data on admission to our hospital. In 70 patients with brainstem hemorrhage (51 men and 19 women aged 29-93, with a mean of 59 gears) who had been admitted to our hospital from 1995 to 2000, we statistically evaluated the association of the outcome with their age and clinical symptoms on admission, blood glucose levels and white blood counts within 6 hours of admission, and the volume and extent of hematoma, concomitant hydrocephalus, and intraventricular perforation on admission CT scans. The mortality tended to be higher, but not significantly (P=0.07), in patients aged 70 years or older (83%) than in those aged less than 70 years (55%). Quadriplegia or decerebrate rigidity (P 2 or higher (P<0.01) on admission were significantly correlated with the prognosis. Hematoma volumes of 6 ml or larger on CT scans were most strongly correlated with the prognosis (P<0.001). Central hematoma and hematoma with extension to the midbrain, thalamus, or medulla oblongata (P<0.05), as well as hemorrhage complicated by hydrocephalus or intraventricular perforation (P<0.01), were correlated with the prognosis. (author)

  3. Brainstem encephalitis and acute polyneuropathy associated with hepatitis E infection.

    Science.gov (United States)

    Salim, Omar Jabbar; Davidson, Amy; Li, Kathy; Leach, John Paul; Heath, Craig

    2017-09-11

    A 59-year-old man presented with feverish illness. His Glasgow Coma Scale was 15, had reduced visual acuity in the left eye with partial left ptosis and mild left hemiparesis with an extensor left plantar. Over 48 hours, he accrued multiple cranial nerves palsies and progressed to a flaccid paralysis necessitating admission to an intensive care unit.Cerebrospinal fluid (CSF) study showed 20 lymphocytes and raised protein. Viral and bacterial PCRs were negative. Samples for Lyme, blood-borne viruses, syphilis and autoantibodies were also negative. MRI brain showed T2 abnormalities within the brainstem. Nerve conduction studies revealed an acute motor and sensory axonal neuropathy pattern of Guillian Barre Syndrome (GBS). The patient was treated for both infective and inflammatory causes of brainstem encephalitis and GBS.Retrospective studies confirmed the presence of hepatitis E virus (HEV) RNA in CSF and serum studies showed positive HEV IgG and IgM prior to intravenous infusion. After 3 months of intensive rehabilitation, the patient was discharged home walking with a frame. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  4. Effect of hydraulic retention time on ABR tail water treatment by contact oxidation process under low oxygen condition

    Science.gov (United States)

    Huang, Xiaolong; Shi, Chunhong; Wang, Zhenbao; Jiang, Kai

    2018-02-01

    Biological contact oxidation process of low dissolved oxygen was applied to the treatment of ABR tail water, which were pretreatment effluent for Island sewage. The reactor was built and filled with polyurethane suspension filler as carrier for biofilm growth in laboratory. The dissolved oxygen in the reactor is kept at 1.3-1.8mg/L to distinguish between traditional method which is 2.5-3.5mg/L. Influence of hydraulic retention time(HRT) on ABR tail water treatment by the process was studied. Results show that the system has good effect on removal of COD and TN under this condition. When HRT is among 4h to 12h, the removal rate of COD can be maintained at 80-90%.From period 1 to period 3, the removal rate of NH4 +N and TN at the end of each period can be recovered to a higher level, and the average removal rate after stabilization is 99% and 67% respectively which can come up to first grade of the national standard GB18918-2002. It is remarkable that when HRT is 4h, the removal rate of NH4 +-N and TN showed a significant decrease trend, the concentration of effluent was 14.79mg/L and 19.5mg/L, respectively.

  5. Comparison of sensitivity of magnetic resonance imaging and evoked potentials in the detection of brainstem involvement in multiple sclerosis

    International Nuclear Information System (INIS)

    Comi, G.; Martinelli, V.; Medaglini, S.; Locatelli, T.; Magnani, G.; Poggi, A.; Triulzi, F.

    1988-01-01

    A comparison was made of the sensitivity of magnetic resonance imaging and the combined use of Brainstem Auditory Evoked Potential and Median Somatosensory Evoked Potential in the detection of brainstem dysfunction in 54 multiple sclerosis patients. 10 refs.; 2 tabs

  6. Visualization of oxytocin release that mediates paired pulse facilitation in hypothalamic pathways to brainstem autonomic neurons.

    Directory of Open Access Journals (Sweden)

    Ramón A Piñol

    Full Text Available Recent work has shown that oxytocin is involved in more than lactation and uterine contraction. The paraventricular nucleus of the hypothalamus (PVN contains neuroendocrine neurons that control the release of hormones, including vasopressin and oxytocin. Other populations of PVN neurons do not release hormones, but rather project to and release neurotransmitters onto other neurons in the CNS involved in fluid retention, thermoregulation, sexual behavior and responses to stress. Activation of oxytocin receptors can be cardioprotective and reduces the adverse cardiovascular consequences of anxiety and stress, yet how oxytocin can affect heart rate and cardiac function is unknown. While anatomical work has shown the presence of peptides, including oxytocin, in the projections from the PVN to parasympathetic nuclei, electrophysiological studies to date have only demonstrated release of glutamate and activation of fast ligand gated receptors in these pathways. In this study, using rats, we directly show, using sniffer CHO cells that express oxytocin receptors and the Ca2+ indicator R-GECO, that optogenetic activation of channelrhodopsin-2 (ChR2 expressing PVN fibers in the brainstem activates oxytocin receptors in the dorsomotor nucleus of the vagus (DMNV. We also demonstrate that while a single photoactivation of PVN terminals only activates glutamatergic receptors in brainstem cardiac vagal neurons (CVNs, neurons that dominate the neural control of heart rate, both the paired pulse facilitation, and sustained enhancement of glutamate release in this pathway is mediated by activation of oxytocin receptors. Our results provide direct evidence that a pathway from the PVN likely releases oxytocin and enhances short-term plasticity of this critical autonomic connection.

  7. Visualization of Oxytocin Release that Mediates Paired Pulse Facilitation in Hypothalamic Pathways to Brainstem Autonomic Neurons

    Science.gov (United States)

    Piñol, Ramón A.; Jameson, Heather; Popratiloff, Anastas; Lee, Norman H.; Mendelowitz, David

    2014-01-01

    Recent work has shown that oxytocin is involved in more than lactation and uterine contraction. The paraventricular nucleus of the hypothalamus (PVN) contains neuroendocrine neurons that control the release of hormones, including vasopressin and oxytocin. Other populations of PVN neurons do not release hormones, but rather project to and release neurotransmitters onto other neurons in the CNS involved in fluid retention, thermoregulation, sexual behavior and responses to stress. Activation of oxytocin receptors can be cardioprotective and reduces the adverse cardiovascular consequences of anxiety and stress, yet how oxytocin can affect heart rate and cardiac function is unknown. While anatomical work has shown the presence of peptides, including oxytocin, in the projections from the PVN to parasympathetic nuclei, electrophysiological studies to date have only demonstrated release of glutamate and activation of fast ligand gated receptors in these pathways. In this study, using rats, we directly show, using sniffer CHO cells that express oxytocin receptors and the Ca2+ indicator R-GECO, that optogenetic activation of channelrhodopsin-2 (ChR2) expressing PVN fibers in the brainstem activates oxytocin receptors in the dorsomotor nucleus of the vagus (DMNV). We also demonstrate that while a single photoactivation of PVN terminals only activates glutamatergic receptors in brainstem cardiac vagal neurons (CVNs), neurons that dominate the neural control of heart rate, both the paired pulse facilitation, and sustained enhancement of glutamate release in this pathway is mediated by activation of oxytocin receptors. Our results provide direct evidence that a pathway from the PVN likely releases oxytocin and enhances short-term plasticity of this critical autonomic connection. PMID:25379676

  8. The role of the auditory brainstem in processing musically-relevant pitch

    Directory of Open Access Journals (Sweden)

    Gavin M. Bidelman

    2013-05-01

    Full Text Available Neuroimaging work has shed light on the cerebral architecture involved in processing the melodic and harmonic aspects of music. Here, recent evidence is reviewed illustrating that subcortical auditory structures contribute to the early formation and processing of musically-relevant pitch. Electrophysiological recordings from the human brainstem and population responses from the auditory nerve reveal that nascent features of tonal music (e.g., consonance/dissonance, pitch salience, harmonic sonority are evident at early, subcortical levels of the auditory pathway. The salience and harmonicity of brainstem activity is strongly correlated with listeners’ perceptual preferences and perceived consonance for the tonal relationships of music. Moreover, the hierarchical ordering of pitch intervals/chords described by the Western music practice and their perceptual consonance is well-predicted by the salience with which pitch combinations are encoded in subcortical auditory structures. While the neural correlates of consonance can be tuned and exaggerated with musical training, they persist even in the absence of musicianship or long-term enculturation. As such, it is posited that the structural foundations of musical pitch might result from innate processing performed by the central auditory system. A neurobiological predisposition for consonant, pleasant sounding pitch relationships may be one reason why these pitch combinations have been favored by composers and listeners for centuries. It is suggested that important perceptual dimensions of music emerge well before the auditory signal reaches cerebral cortex and prior to attentional engagement. While cortical mechanisms are no doubt critical to the perception, production, and enjoyment of music, the contribution of subcortical structures implicates a more integrated, hierarchically organized network underlying music processing within the brain.

  9. Tractography of the brainstem in major depressive disorder using diffusion tensor imaging.

    Directory of Open Access Journals (Sweden)

    Yun Ju C Song

    Full Text Available BACKGROUND: The brainstem is the main region that innervates neurotransmitter release to the Hypothalamic-Pituitary Adrenal (HPA axis and fronto-limbic circuits, two key brain circuits found to be dysfunctional in Major Depressive Disorder (MDD. However, the brainstem's role in MDD has only been evaluated in limited reports. Using Diffusion Tensor Imaging (DTI, we investigated whether major brainstem white matter tracts that relate to these two circuits differ in MDD patients compared to healthy controls. METHODS: MDD patients (n = 95 and age- and gender-matched controls (n = 34 were assessed using probabilistic tractography of DTI to delineate three distinct brainstem tracts: the nigrostriatal tract (connecting brainstem to striatum, solitary tract (connecting brainstem to amygdala and corticospinal tract (connecting brainstem to precentral cortex. Fractional anisotropy (FA was used to measure the white matter integrity of these tracts, and measures were compared between MDD and control participants. RESULTS: MDD participants were characterized by a significant and specific decrease in white matter integrity of the right solitary tract (p<0.009 using independent t-test, which is a "bottom up" afferent pathway that connects the brainstem to the amygdala. This decrease was not related to symptom severity. CONCLUSIONS: The results provide new evidence to suggest that structural connectivity between the brainstem and the amygdala is altered in MDD. These results are interesting in light of predominant theories regarding amygdala-mediated emotional reactivity observed in functional imaging studies of MDD. The characterization of altered white matter integrity in the solitary tract in MDD supports the possibility of dysfunctional brainstem-amygdala connectivity impacting vulnerable circuits in MDD.

  10. AREB1, AREB2, and ABF3 are master transcription factors that cooperatively regulate ABRE-dependent ABA signaling involved in drought stress tolerance and require ABA for full activation.

    Science.gov (United States)

    Yoshida, Takuya; Fujita, Yasunari; Sayama, Hiroko; Kidokoro, Satoshi; Maruyama, Kyonoshin; Mizoi, Junya; Shinozaki, Kazuo; Yamaguchi-Shinozaki, Kazuko

    2010-02-01

    A myriad of drought stress-inducible genes have been reported, and many of these are activated by abscisic acid (ABA). In the promoter regions of such ABA-regulated genes, conserved cis-elements, designated ABA-responsive elements (ABREs), control gene expression via bZIP-type AREB/ABF transcription factors. Although all three members of the AREB/ABF subfamily, AREB1, AREB2, and ABF3, are upregulated by ABA and water stress, it remains unclear whether these are functional homologs. Here, we report that all three AREB/ABF transcription factors require ABA for full activation, can form hetero- or homodimers to function in nuclei, and can interact with SRK2D/SnRK2.2, an SnRK2 protein kinase that was identified as a regulator of AREB1. Along with the tissue-specific expression patterns of these genes and the subcellular localization of their encoded proteins, these findings clearly indicate that AREB1, AREB2, and ABF3 have largely overlapping functions. To elucidate the role of these AREB/ABF transcription factors, we generated an areb1 areb2 abf3 triple mutant. Large-scale transcriptome analysis, which showed that stress-responsive gene expression is remarkably impaired in the triple mutant, revealed novel AREB/ABF downstream genes in response to water stress, including many LEA class and group-Ab PP2C genes and transcription factors. The areb1 areb2 abf3 triple mutant is more resistant to ABA than are the other single and double mutants with respect to primary root growth, and it displays reduced drought tolerance. Thus, these results indicate that AREB1, AREB2, and ABF3 are master transcription factors that cooperatively regulate ABRE-dependent gene expression for ABA signaling under conditions of water stress.

  11. Working memory capacity and visual-verbal cognitive load modulate auditory-sensory gating in the brainstem: toward a unified view of attention.

    Science.gov (United States)

    Sörqvist, Patrik; Stenfelt, Stefan; Rönnberg, Jerker

    2012-11-01

    Two fundamental research questions have driven attention research in the past: One concerns whether selection of relevant information among competing, irrelevant, information takes place at an early or at a late processing stage; the other concerns whether the capacity of attention is limited by a central, domain-general pool of resources or by independent, modality-specific pools. In this article, we contribute to these debates by showing that the auditory-evoked brainstem response (an early stage of auditory processing) to task-irrelevant sound decreases as a function of central working memory load (manipulated with a visual-verbal version of the n-back task). Furthermore, individual differences in central/domain-general working memory capacity modulated the magnitude of the auditory-evoked brainstem response, but only in the high working memory load condition. The results support a unified view of attention whereby the capacity of a late/central mechanism (working memory) modulates early precortical sensory processing.

  12. The effect of pH and operation mode for COD removal of slaughterhouse wastewater with Anaerobic Batch Reactor (ABR

    Directory of Open Access Journals (Sweden)

    Maria Octoviane Dyan

    2015-01-01

    Full Text Available Disposal of industrial wastes in large quantities was not in accordance with today's standards of waste into environmental issues that must be overcome with proper treatment. Similarly, the abattoir wastewater that contains too high organic compounds and suspended solids. The amount of liquid waste disposal Slaughterhouse (SW with high volume also causes pollution. The research aim to resolve this problem by lowering the levels of BOD-COD to comply with effluent quality standard. Anaerobic process is the right process for slaughterhouse wastewater treatment because of high content of organic compounds that can be utilized by anaerobic bacteria as a growth medium. Some research has been conducted among abattoir wastewater treatment using anaerobic reactors such as ABR, UASB and ASBR. Our research focuses on the search for the optimum results decline effluent COD levels to match the quality standards limbah and cow rumen fluid with biodigester ABR (Anaerobic Batch Reactor. The variables used were PH of 6, 7, and 8, as well as the concentration ratio of COD: N is 400:7; 450:7, and 500:7. COD value is set by the addition of N derived from urea [CO(NH2 2]. COD levels will be measured daily by water displacement technique. The research’s result for 20 days seen that optimum PH for biogas production was PH 7,719 ml. The optimum PH for COD removal is PH 6, 72.39 %. The operation mode COD:N for biogas production and COD removal is 500:7, with the production value is 601 ml and COD removal value is 63.85 %. The research’s conclusion, the PH optimum for biogas production was PH 7, then the optimum PH for COD removal is PH 6. The optimum operation mode COD:N for biogas production and COD removal was 500:7

  13. A Clinical Research Study of Cognitive Dysfunction and Affective Impairment after Isolated Brainstem Stroke

    Directory of Open Access Journals (Sweden)

    Xiujuan Fu

    2017-12-01

    Full Text Available Although the function of the cerebellum in neurocognition has been well-documented, the similar role of the brainstem has yet to be fully elucidated. This clinical research study aimed to combine data relating to neuropsychological assessments and P300 to explore cognitive dysfunction and affective impairment following brainstem stroke. Thirty-four patients with isolated brainstem stroke and twenty-six healthy controls were recruited; for each patient, we collated data pertaining to the P300, Addenbrooke's Cognitive Examination III (ACE-III, Montreal Cognitive Assessment Chinese version (MoCA, trail-making test (TMT, Symbol Digit Modalities Test (SDMT, Wechsler Adult Intelligence Scale-Digit Spans (DS, Stroop test, Self Rating Depression Scale (SDS, and Self Rating Anxiety Scale (SAS. Significance was analyzed using an independent T-test or the Mann-Whitney U-test. Correlation was analyzed using Pearson's correlation analysis or Spearman's correlation analysis. Collectively, data revealed that brainstem stroke caused mild cognitive impairment (MCI, and that visuospatial, attention, linguistic, and emotional disturbances may occur after isolated brainstem stroke. Cognitive decline was linked to P300 latency, ACE-III, and MoCA; P300 latency was correlated with ACE-III. Patients with right brainstem lesions were more likely to suffer memory decline. The present study provides initial data relating to the role of the brainstem in neurocognition, and will be useful for further understanding of vascular cognitive and affective impairment.

  14. A Clinical Research Study of Cognitive Dysfunction and Affective Impairment after Isolated Brainstem Stroke

    Science.gov (United States)

    Fu, Xiujuan; Lu, Zuneng; Wang, Yan; Huang, Lifang; Wang, Xi; Zhang, Hong; Xiao, Zheman

    2017-01-01

    Although the function of the cerebellum in neurocognition has been well-documented, the similar role of the brainstem has yet to be fully elucidated. This clinical research study aimed to combine data relating to neuropsychological assessments and P300 to explore cognitive dysfunction and affective impairment following brainstem stroke. Thirty-four patients with isolated brainstem stroke and twenty-six healthy controls were recruited; for each patient, we collated data pertaining to the P300, Addenbrooke's Cognitive Examination III (ACE-III), Montreal Cognitive Assessment Chinese version (MoCA), trail-making test (TMT), Symbol Digit Modalities Test (SDMT), Wechsler Adult Intelligence Scale-Digit Spans (DS), Stroop test, Self Rating Depression Scale (SDS), and Self Rating Anxiety Scale (SAS). Significance was analyzed using an independent T-test or the Mann-Whitney U-test. Correlation was analyzed using Pearson's correlation analysis or Spearman's correlation analysis. Collectively, data revealed that brainstem stroke caused mild cognitive impairment (MCI), and that visuospatial, attention, linguistic, and emotional disturbances may occur after isolated brainstem stroke. Cognitive decline was linked to P300 latency, ACE-III, and MoCA; P300 latency was correlated with ACE-III. Patients with right brainstem lesions were more likely to suffer memory decline. The present study provides initial data relating to the role of the brainstem in neurocognition, and will be useful for further understanding of vascular cognitive and affective impairment. PMID:29311895

  15. Effects of myelin or cell body brainstem lesions on 3-channel Lissajous' trajectories of feline auditory brainstem evoked potentials.

    Science.gov (United States)

    Pratt, H; Zaaroor, M; Bleich, N; Starr, A

    1991-06-01

    Auditory brainstem evoked potentials (ABEP) were recorded from 16 awake cats to obtain 3-Channel Lissajous' Trajectories (3CLTs) using three orthogonal differential electrode configurations (nasion-midline nuchal ridge, left-right mastoids, vertex-midline under the mandible). Potentials, evoked by monaural 80 dBnHL (re, human threshold) clicks, were studied before, and up to 7 weeks after inducing neuronal lesions localized to the cochlear nucleus (CN) or the superior olivary complex (SOC), or myelin lesions localized to the fibers of the trapezoid body connecting these two structures. Neuronal lesions were induced by injection of kainic acid (KA), while myelin lesions were induced by injection of L-alpha-lysophosphatidylcholine (LPC). With CN neuronal lesions the major changes in 3CLT were in the time domain of 'b', 'c' and 'd' (components P2, P3 and P4 of single-channel ABEP). With SOC neuronal lesions the major changes were in 'c' and 'd' of 3CLT (P3 and P4 of ABEP). With trapezoid body lesions the major change was in 'c' (P3 of ABEP). The results are compatible with the peripheral generation of the first ABEP components (P1a and P1b). The second component (P2) is generated by ipsilateral CN neurones and their outputs. The third component (P3) is generated primarily by ipsilateral SOC neurones and their outputs, with the ipsilateral CN providing input. The The fourth component (P4) is generated bilaterally by the SOC neurones and their outputs, receiving their inputs from ipsilateral CN. The fifth ABEP component (P5) is generated by structures central to the SOCs and their immediate outputs. Neither focal neuronal nor myelin lesions were sufficient to produce obliteration of any component, consistent with a set of generators for each of the ABEP components, consisting of both cell bodies and their output fibers, that is distributed spatially in the brainstem.

  16. Tasquinimod (ABR-215050, a quinoline-3-carboxamide anti-angiogenic agent, modulates the expression of thrombospondin-1 in human prostate tumors

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    Isaacs John T

    2010-05-01

    Full Text Available Abstract Background The orally active quinoline-3-carboxamide tasquinimod [ABR-215050; CAS number 254964-60-8, which currently is in a phase II-clinical trial in patients against metastatic prostate cancer, exhibits anti-tumor activity via inhibition of tumor angiogenesis in human and rodent tumors. To further explore the mode of action of tasquinimod, in vitro and in vivo experiments with gene microarray analysis were performed using LNCaP prostate tumor cells. The array data were validated by real-time semiquantitative reversed transcriptase polymerase chain reaction (sqRT-PCR and protein expression techniques. Results One of the most significant differentially expressed genes both in vitro and in vivo after exposure to tasquinimod, was thrombospondin-1 (TSP1. The up-regulation of TSP1 mRNA in LNCaP tumor cells both in vitro and in vivo correlated with an increased expression and extra cellular secretion of TSP1 protein. When nude mice bearing CWR-22RH human prostate tumors were treated with oral tasquinimod, there was a profound growth inhibition, associated with an up-regulation of TSP1 and a down- regulation of HIF-1 alpha protein, androgen receptor protein (AR and glucose transporter-1 protein within the tumor tissue. Changes in TSP1 expression were paralleled by an anti-angiogenic response, as documented by decreased or unchanged tumor tissue levels of VEGF (a HIF-1 alpha down stream target in the tumors from tasquinimod treated mice. Conclusions We conclude that tasquinimod-induced up-regulation of TSP1 is part of a mechanism involving down-regulation of HIF1α and VEGF, which in turn leads to reduced angiogenesis via inhibition of the "angiogenic switch", that could explain tasquinimods therapeutic potential.

  17. Electroretinogram (ERG) to photic stimuli should be carefully distinct from photic brainstem reflex in patients with deep coma.

    Science.gov (United States)

    Mitsuhashi, Masahiro; Hitomi, Takefumi; Aoyama, Akihiro; Kaido, Toshimi; Ikeda, Akio; Takahashi, Ryosuke

    2017-08-31

    Patient 1: A 35-year-old woman became deep coma because of intracranial hemorrhage after pulmonary surgery. Patient 2: A 39-year-old woman became deep coma because of cerebellar hemorrhage after hepatic surgery. Scalp-recorded digital electroencephalography (EEG) showed electrocerebral inactivity in both cases. In addition, both EEG showed repetitive discharges at bilateral frontopolar electrodes in response to photic stimuli. The amplitude and latency of the discharges was 17 μV and 24 msec in case 1, and 9 μV and 27 msec in case 2 respectively. The activity at left frontopolar electrode disappeared after coverage of the ipsilateral eye. Based on these findings, we could exclude the possibility of brainstem response and judged it as electroretinogram (ERG). Photic stimulation is a useful activation method in EEG recording, and we can also evaluate brainstem function by checking photic blink reflex if it is evoked. However, we should be cautious about the distinction of ERG from photic blink reflex when brain death is clinically suspected.

  18. Beneficial auditory and cognitive effects of auditory brainstem implantation in children.

    Science.gov (United States)

    Colletti, Liliana

    2007-09-01

    with a CI, had auditory neuropathy; one child showed total cochlear ossification bilaterally due to meningitis; and one child had profound hearing loss with cochlear fractures after a head injury. Twelve of these children had multiple associated psychomotor handicaps. The retrosigmoid approach was used in all children. Intraoperative electrical auditory brainstem responses (EABRs) and postoperative EABRs and electrical middle latency responses (EMLRs) were performed. Perceptual auditory abilities were evaluated with the Evaluation of Auditory Responses to Speech (EARS) battery - the Listening Progress Profile (LIP), the Meaningful Auditory Integration Scale (MAIS), the Meaningful Use of Speech Scale (MUSS) - and the Category of Auditory Performance (CAP). Cognitive evaluation was performed on seven children using the Leiter International Performance Scale - Revised (LIPS-R) test with the following subtests: Figure ground, Form completion, Sequential order and Repeated pattern. No postoperative complications were observed. All children consistently used their devices for >75% of waking hours and had environmental sound awareness and utterance of words and simple sentences. Their CAP scores ranged from 1 to 7 (average =4); with MAIS they scored 2-97.5% (average =38%); MUSS scores ranged from 5 to 100% (average =49%) and LIP scores from 5 to 100% (average =45%). Owing to associated disabilities, 12 children were given other therapies (e.g. physical therapy and counselling) in addition to speech and aural rehabilitation therapy. Scores for two of the four subtests of LIPS-R in this study increased significantly during the first year of auditory brainstem implant use in all seven children selected for cognitive evaluation.

  19. Specificity determinants for the abscisic acid response element.

    Science.gov (United States)

    Sarkar, Aditya Kumar; Lahiri, Ansuman

    2013-01-01

    Abscisic acid (ABA) response elements (ABREs) are a group of cis-acting DNA elements that have been identified from promoter analysis of many ABA-regulated genes in plants. We are interested in understanding the mechanism of binding specificity between ABREs and a class of bZIP transcription factors known as ABRE binding factors (ABFs). In this work, we have modeled the homodimeric structure of the bZIP domain of ABRE binding factor 1 from Arabidopsis thaliana (AtABF1) and studied its interaction with ACGT core motif-containing ABRE sequences. We have also examined the variation in the stability of the protein-DNA complex upon mutating ABRE sequences using the protein design algorithm FoldX. The high throughput free energy calculations successfully predicted the ability of ABF1 to bind to alternative core motifs like GCGT or AAGT and also rationalized the role of the flanking sequences in determining the specificity of the protein-DNA interaction.

  20. Brain Tumor Therapy-Induced Changes in Normal-Appearing Brainstem Measured With Longitudinal Diffusion Tensor Imaging

    International Nuclear Information System (INIS)

    Hua Chiaho; Merchant, Thomas E.; Gajjar, Amar; Broniscer, Alberto; Zhang, Yong; Li Yimei; Glenn, George R.; Kun, Larry E.; Ogg, Robert J.

    2012-01-01

    Purpose: To characterize therapy-induced changes in normal-appearing brainstems of childhood brain tumor patients by serial diffusion tensor imaging (DTI). Methods and Materials: We analyzed 109 DTI studies from 20 brain tumor patients, aged 4 to 23 years, with normal-appearing brainstems included in the treatment fields. Those with medulloblastomas, supratentorial primitive neuroectodermal tumors, and atypical teratoid rhabdoid tumors (n = 10) received postoperative craniospinal irradiation (23.4–39.6 Gy) and a cumulative dose of 55.8 Gy to the primary site, followed by four cycles of high-dose chemotherapy. Patients with high-grade gliomas (n = 10) received erlotinib during and after irradiation (54–59.4 Gy). Parametric maps of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were computed and spatially registered to three-dimensional radiation dose data. Volumes of interest included corticospinal tracts, medial lemnisci, and the pons. Serving as an age-related benchmark for comparison, 37 DTI studies from 20 healthy volunteers, aged 6 to 25 years, were included in the analysis. Results: The median DTI follow-up time was 3.5 years (range, 1.6–5.0 years). The median mean dose to the pons was 56 Gy (range, 7–59 Gy). Three patterns were seen in longitudinal FA and apparent diffusion coefficient changes: (1) a stable or normal developing time trend, (2) initial deviation from normal with subsequent recovery, and (3) progressive deviation without evidence of complete recovery. The maximal decline in FA often occurred 1.5 to 3.5 years after the start of radiation therapy. A full recovery time trend could be observed within 4 years. Patients with incomplete recovery often had a larger decline in FA within the first year. Radiation dose alone did not predict long-term recovery patterns. Conclusions: Variations existed among individual patients after therapy in longitudinal evolution of brainstem white matter injury and recovery. Early response

  1. Herpetic brainstem encephalitis: report of a post-mortem case studied electron microscopically and immunohisiochemically

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    José Eymard Homem Pitella

    1987-03-01

    Full Text Available A post-mortem examined case of herpetic brainstem encephalitis is presented. Clinically, the patient had cephalea followed by ataxia, drowsiness and multiple palsies of some cranial nerves, developing into death in eight days. The pathologic examination of the brain showed necrotizing encephalitis in multiple foci limited to the brainstem, more distinctly in the pons and medula oblongata. The technique of immunoperoxidase revealed rare glial cells with intranuclear immunoreactivity for herpes antigen. Rare viral particles with the morphological characteristics of the herpesvirus were identified in the nuclei of neurons in 10% formol fixed material. This is the second reported case of herpetic brainstem encephalitis confirmed by post-mortem examination. The pathway used by the virus to reach the central nervous system and its posterior dissemination to the oral cavity, the orbitofrontal region and the temporal lobes as well as to the brainstem, after a period of latency and reactivation, are discussed.

  2. Leucoencephalopathy with brainstem and spinal cord involvement and high lactate: quantitative magnetic resonance imaging

    NARCIS (Netherlands)

    Steenweg, M.E.; Pouwels, P.J.W.; Wolf, N.I.; van Wieringen, W.N.; Barkhof, F.; van der Knaap, M.S.

    2011-01-01

    Leucoencephalopathy with brainstem and spinal cord involvement and elevated lactate is a white matter disorder caused by DARS2 mutations. The pathology is unknown. We observed striking discrepancies between improvement on longitudinal conventional magnetic resonance images and clinical deterioration

  3. Organization of diencephalic and brainstem afferent projections to the lateral septum in the rat

    NARCIS (Netherlands)

    Luiten, Paul G.M.; Kuipers, Folkert; Schuitmaker, Hans

    1982-01-01

    Ascending diencephalic and brainstem afferents to the lateral septal column were studied by retrograde transport of horseradish peroxidase following microiontophoretic injections in the various subdivisions of the lateral septal area. Predominantly ispilateral cells, of which several coincide with

  4. A probabilistic atlas of human brainstem pathways based on connectome imaging data.

    Science.gov (United States)

    Tang, Yuchun; Sun, Wei; Toga, Arthur W; Ringman, John M; Shi, Yonggang

    2018-04-01

    The brainstem is a critical structure that regulates vital autonomic functions, houses the cranial nerves and their nuclei, relays motor and sensory information between the brain and spinal cord, and modulates cognition, mood, and emotions. As a primary relay center, the fiber pathways of the brainstem include efferent and afferent connections among the cerebral cortex, spinal cord, and cerebellum. While diffusion MRI has been successfully applied to map various brain pathways, its application for the in vivo imaging of the brainstem pathways has been limited due to inadequate resolution and large susceptibility-induced distortion artifacts. With the release of high-resolution data from the Human Connectome Project (HCP), there is increasing interest in mapping human brainstem pathways. Previous works relying on HCP data to study brainstem pathways, however, did not consider the prevalence (>80%) of large distortions in the brainstem even after the application of correction procedures from the HCP-Pipeline. They were also limited in the lack of adequate consideration of subject variability in either fiber pathways or region of interests (ROIs) used for bundle reconstruction. To overcome these limitations, we develop in this work a probabilistic atlas of 23 major brainstem bundles using high-quality HCP data passing rigorous quality control. For the large-scale data from the 500-Subject release of HCP, we conducted extensive quality controls to exclude subjects with severe distortions in the brainstem area. After that, we developed a systematic protocol to manually delineate 1300 ROIs on 20 HCP subjects (10 males; 10 females) for the reconstruction of fiber bundles using tractography techniques. Finally, we leveraged our novel connectome modeling techniques including high order fiber orientation distribution (FOD) reconstruction from multi-shell diffusion imaging and topography-preserving tract filtering algorithms to successfully reconstruct the 23 fiber bundles

  5. Purinergic receptors are involved in tooth-pulp evoked nocifensive behavior and brainstem neuronal activity

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    Sessle Barry J

    2010-09-01

    Full Text Available Abstract Background To evaluate whether P2X receptors are involved in responses to noxious pulp stimulation, the P2X3 and P2X2/3 receptor agonist α,β-methyleneATP (α,β-meATP was applied to the molar tooth pulp and nocifensive behavior and extracellular-signal regulated kinase (ERK phosphorylation in trigeminal spinal subnucleus caudalis (Vc, trigeminal spinal subnucleus interpolaris (Vi, upper cervical spinal cord (C1/C2 and paratrigeminal nucleus (Pa5 neurons were analyzed in rats. Results Genioglossus (GG muscle activity was evoked by pulpal application of 100 mM α,β-meATP and was significantly larger than GG activity following vehicle (phosphate-buffered saline PBS application (p 1, P2X3 and, P2X2/3 antagonist. A large number of pERK-LI cells were expressed in the Vc, Vi/Vc, C1/C2 and Pa5 at 5 min following pulpal application of 100 mM α,β-meATP compared to PBS application to the pulp (p Conclusions The present findings suggest that activation of P2X3 and P2X2/3 receptors in the tooth pulp is sufficient to elicit nociceptive behavioral responses and trigeminal brainstem neuronal activity.

  6. Combined CMV- and HSV-1 brainstem encephalitis restricted to medulla oblongata.

    Science.gov (United States)

    Katchanov, J; Branding, G; Stocker, H

    2014-04-15

    We report a very rare case of a combined CMV- and HSV-1 isolated brainstem encephalitis restricted to medulla oblongata in a patient with advanced HIV disease. Neither limbic nor general ventricular involvement was detected on neuroimaging. The case highlights the importance of testing for HSV-1 and CMV in HIV-infected patients presenting with an isolated brainstem syndrome. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Prodominant hypertensive brainstem encephalopathy with supratentorial involvement: Case report and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Hee; Park, Sung Tae; Lim, Hyun Kyung [Dept. of Radiology, Soonchunhyang University Hospital, Soonchunhyang University School of Medicine, Seoul (Korea, Republic of); Kim, Sung Tae; Cha, Ji Hoon [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2014-12-15

    Hypertensive encephalopathy typically presents with bilateral parietooccipital vasogenic edema. Brainstem and cerebellar edema are uncommon in association with typical supratentorial changes. We experienced three cases of atypical hypertensive encephalopathy involving brainstem and cerebellum as well as cerebral white matter, which showed characteristic alternating linear bright and low signals in the pons, the so-called 'stripe sign'. We report these cases here with a brief literature review.

  8. Modeling Parkinson's disease falls associated with brainstem cholinergic systems decline.

    Science.gov (United States)

    Kucinski, Aaron; Sarter, Martin

    2015-04-01

    In addition to the primary disease-defining symptoms, approximately half of patients with Parkinson's disease (PD) suffer from postural instability, impairments in gait control and a propensity for falls. Consistent with evidence from patients, we previously demonstrated that combined striatal dopamine (DA) and basal forebrain (BF) cholinergic cell loss causes falls in rats traversing dynamic surfaces. Because evidence suggests that degeneration of brainstem cholinergic neurons arising from the pedunculopontine nucleus (PPN) also contributes to impaired gait and falls, here we assessed the effects of selective cholinergic PPN lesions in combination with striatal DA loss or BF cholinergic cells loss as well as losses in all 3 regions. Results indicate that all combination losses that included the BF cholinergic system slowed traversal and increased slips and falls. However, the performance of rats with losses in all 3 regions (PPN, BF, and DA) was not more severely impaired than following combined BF cholinergic and striatal DA lesions. These results confirm the hypothesis that BF cholinergic-striatal disruption of attentional-motor interactions is a primary source of falls. Additional losses of PPN cholinergic neurons may worsen posture and gait control in situations not captured by the current testing conditions. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  9. CT findings of traumatic primary brain-stem injury

    International Nuclear Information System (INIS)

    Hosaka, Yasuaki; Hatashita, Shizuo; Bandou, Kuniaki; Ueki, Yasuyuki; Abe, Kouzou; Koga, Nobunori; Sugimura, Jun; Sakakibara, Tokiwa; Takagi, Suguru

    1984-01-01

    A series of 27 consecutive patients with traumatic primary brain stem injuries was studied. They were diagnosed by means of clinical signs, neurological examination, and computerized tomography (CT). The CT findings of the brain-stem lesions were classified into 4 types: Type H, spotty, high-density; Type H and L, high- and low-densities; Type L, low-density; Type I, isodensity. The Glasgow coma scale (GCS), neurological findings on admission, CT findings (findings in the brain stem, obliteration of perimesencephalic cistern (PMC), and other findings), and the Glasgow outcome scale (GOS) were examined. In the 9 cases of Type H, there was a correlation between the GCS and the GOS, and the spotty, high-density lesions were localized mainly in the dorsal and/or ventral midbrain parenchyma, but these lesions did not show focal signs and symptoms. Without an obliteration of the PMC, Type-H patients did not always have a bad outcome. In the 4 cases of Type H and L, the 2 cases of Type L, and the 12 cases of Type I, there was an obliteration of the PMC. All of the these cases had a bad outcome (1 case of moderate disability, 3 cases of severe disability, and 14 cases of death). The mechanism producing a spotty, high-density area was discussed. The weaker impact (than the other types) and individual anatomical differences weresupposed to make for a spotty, high-density are in the brain stem. (author)

  10. Brainstem Auditory Evoked Potentials in Patients with Subarachnoid Haemorrhage

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    Mikhail Matveev

    2009-10-01

    Full Text Available Objective. The aim of the present study is to typify BAEPs configurations of patients with different location of lesions caused by subarachnoid haemorrhage (SAH and the ensuing complications, in view of assessing the auditory-brainstem system disturbance.Methods. The typization was performed by comparing BAEPs with standard patterns from two sets of types of BAEPs by ipsilateral and binaural stimulation and by cross-stimulation.Results. 94 BAEPs were used for collection of normal referential values: for the absolute latencies and the absolute amplitudes of waves I, II, III, IV and V; for inter-peak latencies I-III, II-III, III-V, I-V and II-V; for amplitude ratios I/V and III/V. 146 BAEPs of patients with mild SAH and 55 from patients with severe SAH, were typified. In 5 types of BAEPs out of a total of 11, the percentage of the potentials in patients with mild SAH and severe SAH differed significantly (p<0.01.Conclusions. The use of sets of types of BAEPs by ipsilateral, binaural and cross-stimulation correctly classifies the potentials in patients with mild and severe SAH.

  11. Gestational flu exposure induces changes in neurochemicals, affiliative hormones and brainstem inflammation, in addition to autism-like behaviors in mice.

    Science.gov (United States)

    Miller, V M; Zhu, Y; Bucher, C; McGinnis, W; Ryan, L K; Siegel, A; Zalcman, S

    2013-10-01

    The prevalence of neurodevelopmental disorders such as autism is increasing, however the etiology of these disorders is unclear and thought to involve a combination of genetic, environmental and immune factors. A recent epidemiological study found that gestational viral exposure during the first trimester increases risk of autism in offspring by twofold. In mice gestational viral exposures alter behavior of offspring, but the biological mechanisms which underpin these behavioral changes are unclear. We hypothesized that gestational viral exposure induces changes in affiliative hormones, brainstem autonomic nuclei and neurotransmitters which are associated with behavioral alterations in offspring. To address this hypothesis, we exposed pregnant mice to influenza A virus (H3N2) on gestational day 9 and determined behavioral, hormonal and brainstem changes in male and female offspring. We found that gestational flu exposure induced dose-dependent alterations in social and aggressive behaviors (p≤0.05) in male and female offspring and increases in locomotor behaviors particularly in male offspring (p≤0.05). We found that flu exposure was also associated with reductions in oxytocin and serotonin (p≤0.05) levels in male and female offspring and sex-specific changes in dopamine metabolism. In addition we found changes in catecholaminergic and microglia density in brainstem tissues of male flu exposed offspring only (p≤0.05). This study demonstrates that gestational viral exposure induces behavioral changes in mice, which are associated with alterations in affiliative hormones. In addition we found sex-specific changes in locomotor behavior, which may be associated with sex-specific alterations in dopamine metabolism and brainstem inflammation. Further investigations into maternal immune responses are necessary to unravel the molecular mechanisms which underpin abnormal hormonal, immune and behavioral responses in offspring after gestational viral exposure

  12. Analysis of diffuse brain injury with primary brainstem lesion on MRI

    International Nuclear Information System (INIS)

    Shibata, Masayoshi; Matsumae, Mitsunori; Shimoda, Masami; Ishizaka, Hideo; Shiramizu, Hideki; Morita, Seiji; Tsugane, Ryuichi

    2003-01-01

    It has been reported that diffuse brain injury patients with primary brainstem lesions have a poor prognosis. Predicting the existence of brainstem injury at hospital arrival is problematic in actual clinical practice. We conducted magnetic resonance imaging (MRI), to visualize brainstem lesions clearly, and retrospectively analyzed predictive factors of brainstem lesions by stepwise multiple logistic regression analysis of patient characteristics, neurological findings, laboratory data, and CT findings at arrival in each case. We compared 24 patients with brainstem lesion and 60 without using MRI obtained less than 3 weeks after admission. Items investigated were blood pressure immediately after hospital arrival, arterial blood gas analysis, existence of abnormal respiration, blow direction, Glasgow coma scale (GCS), light reflex, oculocephalic reflex, corneal reflex, intracranial pressure, jugular venous oxygen saturation, and CT findings such as existence of subarachnoid hemorrhage at the suprasellar cistern, perimesencephalic cistern and convexity, lesions on the thalamus and basal ganglia, gliding contusion, intraventricular hemorrhage and Traumatic Coma Data Bank classification. Independent predictive factors of primary brainstem lesion included impaired light reflex (odds ratio: 2.269), subarachnoid hemorrhage at convexity (odds ratio: 3.592) and suprasellar cistern (odds ratio: 2.458), and Traumatic Coma Data Bank group III (odds ratio: 11.062). (author)

  13. A clinical study of brainstem infarction identified on magnetic resonance imaging

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    Watanabe, Masaki; Takahashi, Akira (Nagoya Univ. (Japan). Faculty of Medicine); Arahata, Yutaka; Motegi, Yoshimasa; Furuse, Masahiro

    1993-04-01

    We conducted a clinical study of 155 cases that were confirmed to have brainstem infarctions on MRI (T[sub 1]-weighted image showed a low signal and T[sub 2]-weighted image showed a high signal, measuring in excess of 2 x 2 mm). The majority of the brainstem infarction was located in the pontine base in 132 cases (85.2%). Of these, 19 cases had double lesions including infarctions in the pontine base. Second infarctions frequently occurred in the cerebral peduncle or medical medulla oblongata, unilateral to the pontine infarctions. In addition to 98 symptomatic cases, there were 57 cases of 'asymptomatic' brainstem infarction. They comprised 24 cases accompanying other symptomatic cerebrovascular diseases in the supratentorium and 33 cases of transient subjective complaints such as headache or vertigo-dizziness. Complication by supratentorial infarctions was significantly frequent in cases of brainstem infarction (p<0.001), 122 of 155 cases (78.7%), especially in the pontine base (88.6%); while in the control cases (without brainstem infarction) only 65 of 221 cases (29.4%). These findings are considered to show the widespread progress of arteriosclerosis in brainstem infarction, especially in ones in the pontine base. (author).

  14. [Distribution of human enterovirus 71 in brainstem of infants with brain stem encephalitis and infection mechanism].

    Science.gov (United States)

    Hao, Bo; Gao, Di; Tang, Da-Wei; Wang, Xiao-Guang; Liu, Shui-Ping; Kong, Xiao-Ping; Liu, Chao; Huang, Jing-Lu; Bi, Qi-Ming; Quan, Li; Luo, Bin

    2012-04-01

    To explore the mechanism that how human enterovirus 71 (EV71) invades the brainstem and how intercellular adhesion molecules-1 (ICAM-1) participates by analyzing the expression and distribution of human EV71, and ICAM-1 in brainstem of infants with brain stem encephalitis. Twenty-two brainstem of infants with brain stem encephalitis were collected as the experimental group and 10 brainstems of fatal congenital heart disease were selected as the control group. The sections with perivascular cuffings were selected to observe EV71-VP1 expression by immunohistochemistry method and ICAM-1 expression was detected for the sections with EV71-VP1 positive expression. The staining image analysis and statistics analysis were performed. The experiment and control groups were compared. (1) EV71-VP1 positive cells in the experimental group were mainly astrocytes in brainstem with nigger-brown particles, and the control group was negative. (2) ICAM-1 positive cells showed nigger-brown. The expression in inflammatory cells (around blood vessels of brain stem and in glial nodules) and gliocytes increased. The results showed statistical difference comparing with control group (P diagnose fatal EV71 infection in infants. EV71 can invade the brainstem via hematogenous route. ICAM-1 may play an important role in the pathogenic process.

  15. Perinatal low-protein diet alters brainstem antioxidant metabolism in adult offspring.

    Science.gov (United States)

    Ferreira, Diorginis Soares; Liu, Yuri; Fernandes, Mariana Pinheiro; Lagranha, Claudia Jacques

    2016-10-01

    Studies in humans and animal models have established a close relationship between early environment insult and subsequent risk of development of non-communicable diseases, including the cardiovascular. Whereas experimental evidences highlight the early undernutrition and the late cardiovascular disease relation, the central mechanisms linking the two remain unknown. Owing to the oxidative balance influence in several pathologies, the aim of the present study was to evaluate the effects of maternal undernutrition (i.e. a low-protein (LP) diet) on oxidative balance in the brainstem. Male rats from mothers fed with an LP diet (8% casein) throughout the perinatal period (i.e. gestation and lactation) showed 10× higher lipid peroxidation levels than animals treated with normoprotein (17% casein) at 100 days of age. In addition, we observed the following reductions in enzymatic activities: superoxide dismutase, 16%; catalase, 30%; glutathione peroxidase, 34%; glutathione-S-transferase, 51%; glutathione reductase, 23%; glucose-6-phosphate dehydrogenase, 31%; and in non-enzymatic glutathione system, 46%. This study is the first to focus on the role of maternal LP nutrition in oxidative balance in a central nervous system structure responsible for cardiovascular control in adult rats. Our data observed changes in oxidative balance in the offspring, therefore, bring a new concept related to early undernutrition and can help in the development of a new clinical strategy to combat the effects of nutritional insult. Wherein the central oxidative imbalance is a feasible mechanism underlying the hypertension risk in adulthood triggered by maternal LP diet.

  16. Curcumin decreases astrocytic reaction after gliotoxic injury in the rat brainstem

    Directory of Open Access Journals (Sweden)

    Eduardo Bondan

    Full Text Available ABSTRACT Recent studies have demonstrated that curcumin (Cur has antioxidant, anti-inflammatory and anti-fibrotic effects. Ethidium bromide (EB injections into the central nervous system (CNS are known to induce local oligodendroglial and astrocytic loss, resulting in primary demyelination and neuroinflammation. Peripheral astrogliosis is seen around the injury site with increased immunoreactivity to glial fibrillary acidic protein (GFAP. This investigation aimed to evaluate the effect of Cur administration on astrocytic response following gliotoxic injury. Wistar rats were injected with EB into the cisterna pontis and treated, or not, with Cur (100 mg/kg/day, intraperitoneal route during the experimental period. Brainstem sections were collected at 15, 21 and 31 days after EB injection and processed for GFAP immunohistochemical staining. Astrocytic reactivity was measured in a computerized system for image analysis. In Cur-treated rats, the GFAP-stained area around the lesion was significantly smaller in all periods after EB injection compared to untreated animals, showing that Cur reduces glial scar development following injury.

  17. Diffusion tensor imaging of the inferior colliculus and brainstem auditory-evoked potentials in preterm infants

    Energy Technology Data Exchange (ETDEWEB)

    Reiman, Milla; Lehtonen, Liisa; Lapinleimu, Helena [Turku University Central Hospital, Department of Paediatrics, Turku (Finland); Parkkola, Riitta [Turku University Central Hospital, Department of Radiology and Turku PET Centre, Turku (Finland); Johansson, Reijo [Turku University Central Hospital, Department of Otorhinolaryngology, Turku (Finland); Jaeaeskelaeinen, Satu K. [Turku University Central Hospital, Department of Clinical Neurophysiology, Turku (Finland); Kujari, Harry [Turku University Central Hospital, Department of Pathology, Turku (Finland); Haataja, Leena [Turku University Central Hospital, Department of Paediatric Neurology, Turku (Finland)

    2009-08-15

    Preterm and low-birth-weight infants have an increased risk of sensorineural hearing loss. Brainstem auditory-evoked potentials (BAEP) are an effective method to detect subtle deficits in impulse conduction in the auditory pathway. Abnormalities on diffusion tensor imaging (DTI) have been shown to be associated with perinatal white-matter injury and reduced fractional anisotropy (FA) has been reported in patients with sensorineural hearing loss. To evaluate the possibility of a correlation between BAEP and DTI of the inferior colliculus in preterm infants. DTI at term age and BAEP measurements were performed on all very-low-birth-weight or very preterm study infants (n=56). FA and apparent diffusion coefficient (ADC) of the inferior colliculus were measured from the DTI. Shorter BAEP wave I, III, and V latencies and I-III and I-V intervals and higher wave V amplitude correlated with higher FA of the inferior colliculus. The association between the DTI findings of the inferior colliculus and BAEP responses suggests that DTI can be used to assess the integrity of the auditory pathway in preterm infants. (orig.)

  18. Diffusion tensor imaging of the inferior colliculus and brainstem auditory-evoked potentials in preterm infants

    International Nuclear Information System (INIS)

    Reiman, Milla; Lehtonen, Liisa; Lapinleimu, Helena; Parkkola, Riitta; Johansson, Reijo; Jaeaeskelaeinen, Satu K.; Kujari, Harry; Haataja, Leena

    2009-01-01

    Preterm and low-birth-weight infants have an increased risk of sensorineural hearing loss. Brainstem auditory-evoked potentials (BAEP) are an effective method to detect subtle deficits in impulse conduction in the auditory pathway. Abnormalities on diffusion tensor imaging (DTI) have been shown to be associated with perinatal white-matter injury and reduced fractional anisotropy (FA) has been reported in patients with sensorineural hearing loss. To evaluate the possibility of a correlation between BAEP and DTI of the inferior colliculus in preterm infants. DTI at term age and BAEP measurements were performed on all very-low-birth-weight or very preterm study infants (n=56). FA and apparent diffusion coefficient (ADC) of the inferior colliculus were measured from the DTI. Shorter BAEP wave I, III, and V latencies and I-III and I-V intervals and higher wave V amplitude correlated with higher FA of the inferior colliculus. The association between the DTI findings of the inferior colliculus and BAEP responses suggests that DTI can be used to assess the integrity of the auditory pathway in preterm infants. (orig.)

  19. Direct projections from hypothalamic orexin neurons to brainstem cardiac vagal neurons.

    Science.gov (United States)

    Dergacheva, Olga; Yamanaka, Akihiro; Schwartz, Alan R; Polotsky, Vsevolod Y; Mendelowitz, David

    2016-12-17

    Orexin neurons are known to augment the sympathetic control of cardiovascular function, however the role of orexin neurons in parasympathetic cardiac regulation remains unclear. To test the hypothesis that orexin neurons contribute to parasympathetic control we selectively expressed channelrhodopsin-2 (ChR2) in orexin neurons in orexin-Cre transgenic rats and examined postsynaptic currents in cardiac vagal neurons (CVNs) in the dorsal motor nucleus of the vagus (DMV). Simultaneous photostimulation and recording in ChR2-expressing orexin neurons in the lateral hypothalamus resulted in reliable action potential firing as well as large whole-cell currents suggesting a strong expression of ChR2 and reliable optogenetic excitation. Photostimulation of ChR2-expressing fibers in the DMV elicited short-latency (ranging from 3.2ms to 8.5ms) postsynaptic currents in 16 out of 44 CVNs tested. These responses were heterogeneous and included excitatory glutamatergic (63%) and inhibitory GABAergic (37%) postsynaptic currents. The results from this study suggest different sub-population of orexin neurons may exert diverse influences on brainstem CVNs and therefore may play distinct functional roles in parasympathetic control of the heart. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  20. Imaging of glial cell morphology, SOD1 distribution and elemental composition in the brainstem and hippocampus of the ALS hSOD1G93A rat.

    Science.gov (United States)

    Stamenković, Stefan; Dučić, Tanja; Stamenković, Vera; Kranz, Alexander; Andjus, Pavle R

    2017-08-15

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder affecting motor and cognitive domains of the CNS. Mutations in the Cu,Zn-superoxide dismutase (SOD1) cause 20% of familial ALS and provoke formation of intracellular aggregates and copper and zinc unbinding, leading to glial activation and neurodegeneration. Therefore, we investigated glial cell morphology, intracellular SOD1 distribution, and elemental composition in the brainstem and hippocampus of the hSOD1 G93A transgenic rat model of ALS. Immunostaining for astrocytes, microglia and SOD1 revealed glial proliferation and progressive tissue accumulation of SOD1 in both brain regions of ALS rats starting already at the presymptomatic stage. Glial cell morphology analysis in the brainstem of ALS rats revealed astrocyte activation occurring before disease symptoms onset, followed by activation of microglia. Hippocampal ALS astrocytes exhibited an identical reactive profile, while microglial morphology was unchanged. Additionally, ALS brainstem astrocytes demonstrated progressive SOD1 accumulation in the cell body and processes, while microglial SOD1 levels were reduced and its distribution limited to distal cell processes. In the hippocampus both glial cell types exhibited SOD1 accumulation in the cell body. X-ray fluorescence imaging revealed decreased P and increased Ca, Cl, K, Ni, Cu and Zn in the brainstem, and higher levels of Cl, Ni and Cu, but lower levels of Zn in the hippocampus of symptomatic ALS rats. These results bring new insights into the glial response during disease development and progression in motor as well as in non-motor CNS structures, and indicate disturbed tissue elemental homeostasis as a prominent hallmark of disease pathology. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  1. Experiences from Auditory Brainstem Implantation (ABIs) in four paediatric patients.

    Science.gov (United States)

    Lundin, Karin; Stillesjö, Fredrik; Nyberg, Gunnar; Rask-Andersen, Helge

    2016-01-01

    Indications for auditory brainstem implants (ABIs) have been widened from patients with neurofibromatosis type 2 (NF2) to paediatric patients with congenital cochlear malformations, cochlear nerve hypoplasia/aplasia, or cochlear ossification after meningitis. We present four ABI surgeries performed in children at Uppsala University Hospital in Sweden since 2009. Three children were implanted with implants from Cochlear Ltd. (Lane Cove, Australia) and one child with an implant from MedEl GMBH (Innsbruck, Austria). A boy with Goldenhar syndrome was implanted with a Cochlear Nucleus ABI24M at age 2 years (patient 1). Another boy with CHARGE syndrome was implanted with a Cochlear Nucleus ABI541 at age 2.5 years (patient 2). Another boy with post-ossification meningitis was implanted with a Cochlear Nucleus ABI24M at age 4 years (patient 3). A girl with cochlear aplasia was implanted with a MedEl Synchrony ABI at age 3 years (patient 4). In patients 1, 2, and 3, the trans-labyrinthine approach was used, and in patient 4 the retro-sigmoid approach was used. Three of the four children benefited from their ABIs and use it full time. Two of the full time users had categories of auditory performance (CAP) score of 4 at their last follow up visit (6 and 2.5 years postoperative) which means they can discriminate consistently any combination of two of Ling's sounds. One child has not been fully evaluated yet, but is a full time user and had CAP 2 (responds to speech sounds) after 3 months of ABI use. No severe side or unpleasant stimulation effects have been observed so far. There was one case of immediate electrode migration and one case of implant device failure after 6.5 years. ABI should be considered as an option in the rehabilitation of children with similar diagnoses.

  2. Brainstem auditory-evoked potential in Boxer dogs

    Directory of Open Access Journals (Sweden)

    Mariana Isa Poci Palumbo

    2014-10-01

    Full Text Available Brainstem auditory-evoked potential (BAEP has been widely used for different purposes in veterinary practice and is commonly used to identify inherited deafness and presbycusis. In this study, 43 Boxer dogs were evaluated using the BAEP. Deafness was diagnosed in 3 dogs (2 bilateral and 1 unilateral allowing the remaining 40 Boxers to be included for normative data analysis including an evaluation on the influence of age on the BAEP. The animals were divided into 2 groups of 20 Boxers each based on age. The mean age was 4.54 years (range, 1-8 in group I, and 9.83 years (range, 8.5-12 in group II. The mean latency for I, III, and V waves were 1.14 (±0.07, 2.64 (±0.11, and 3.48 (±0.10 ms in group I, and 1.20 (±0.12, 2.73 (±0.15, and 3.58 (±0.22 ms in group II, respectively. The mean inter-peak latencies for the I-III, III-V and I-V intervals were 1.50 (±0.15, 0.84 (±0.15, and 2.34 (±0.11 ms in group I, and 1.53 (±0.16, 0.85 (±0.15, and 2.38 (±0.19 ms in group II, respectively. Latencies of waves I and III were significant different between group I and II. For the I-III, III-V and I-V intervals, no significant differences were observed between the 2 groups. As far as we know, this is the first normative study of BAEP obtained from Boxer dogs.

  3. Recent Changes to ABR Maintenance of Certification Part 4 (PQI): Acknowledgment of Radiologists' Activities to Improve Quality and Safety.

    Science.gov (United States)

    Donnelly, Lane F; Mathews, Vincent P; Laszakovits, David J; Jackson, Valerie P; Guiberteau, Milton J

    2016-02-01

    The ABR has recently reviewed and revised its policy establishing how ABR diplomates may comply with requirements for Maintenance of Certification Part 4: Practice Quality Improvement (PQI). The changes were deemed necessary by the Board of Trustees to acknowledge and credit the numerous ways in which radiology professionals contribute to improving patient care through existing and evolving activities available to them within the radiology community. In addition to meeting requirements by completing a traditional PQI project, the policy revision now allows diplomates to meet criteria by completing one of a number of activities in an expanded spectrum of PQI options recognized by the ABR. The new policy also acknowledges the maturing state of quality improvement science by permitting PQI projects to use "any standard quality improvement methodology," such as Six Sigma, Lean, the Institute for Healthcare Improvement's Model for Improvement, and others in addition to the previously prescribed three-phase plan-do-study-act format. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  4. Neonatal neurological disorders involving the brainstem: neurosonographic approaches through the squamous suture and the foramen magnum

    International Nuclear Information System (INIS)

    Tu, Yi-Fang; Chen, Cheng-Yu; Lin, Yuh-Jey; Chang, Ying-Chao; Huang, Chao-Ching

    2005-01-01

    Brainstem damage which often indicates a critical condition is usually underestimated by trans-anterior-fontanel neurosonography (NS) owing to the far-field limitations. Instead, NS alternately scanning through the squamous suture of the temporal bones and the foramen magnum could provide a better visualization of the brainstem structures. The NS characteristics of brainstem lesions caused by various neonatal neurological disorders, such as hypoxic-ischemic encephalopathy (HIE), metabolic encephalopathy, birth trauma and bacterial meningoencephalitis, can be depicted at the acute stage. An echogenic change in the midbrain was found in patients with HIE or metabolic encephalopathy. In addition to the echogenic change, bilateral transtentorial temporal lobe herniation distorting the contour of the midbrain was observed in a patient with group B streptococcus meningoencephalitis, whereas echogenic changes at the level of the pons and/or the medulla oblongata, mainly localized in the dorsal part, could be observed in newborns with severe HIE, maple syrup urine disease or birth trauma. In this pictorial assay, we demonstrate the feasibility of NS imaging in evaluating the entire brainstem structure of critically ill neonates in the near field and illustrate the characteristic features of brainstem involvement in various neonatal neurological disorders along with computed tomography or magnetic resonance imaging correlation. (orig.)

  5. Neonatal neurological disorders involving the brainstem: neurosonographic approaches through the squamous suture and the foramen magnum

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Yi-Fang [National Cheng Kung University Hospital, Department of Emergency Medicine, Tainan (Taiwan); Chen, Cheng-Yu [National Defense Medical Center, Department of Radiology, Taipei (Taiwan); Lin, Yuh-Jey [National Cheng Kung University Hospital, Department of Pediatrics, Tainan (Taiwan); Chang, Ying-Chao [Kaohsiung Chang Gung Children Hospital, Department of Pediatrics, Kaohsiung (Taiwan); Huang, Chao-Ching [National Cheng Kung University Hospital, Department of Pediatrics, Tainan (Taiwan); National Cheng Kung University Hospital, Department of Institute of Molecular Medicine, Tainan (Taiwan)

    2005-09-01

    Brainstem damage which often indicates a critical condition is usually underestimated by trans-anterior-fontanel neurosonography (NS) owing to the far-field limitations. Instead, NS alternately scanning through the squamous suture of the temporal bones and the foramen magnum could provide a better visualization of the brainstem structures. The NS characteristics of brainstem lesions caused by various neonatal neurological disorders, such as hypoxic-ischemic encephalopathy (HIE), metabolic encephalopathy, birth trauma and bacterial meningoencephalitis, can be depicted at the acute stage. An echogenic change in the midbrain was found in patients with HIE or metabolic encephalopathy. In addition to the echogenic change, bilateral transtentorial temporal lobe herniation distorting the contour of the midbrain was observed in a patient with group B streptococcus meningoencephalitis, whereas echogenic changes at the level of the pons and/or the medulla oblongata, mainly localized in the dorsal part, could be observed in newborns with severe HIE, maple syrup urine disease or birth trauma. In this pictorial assay, we demonstrate the feasibility of NS imaging in evaluating the entire brainstem structure of critically ill neonates in the near field and illustrate the characteristic features of brainstem involvement in various neonatal neurological disorders along with computed tomography or magnetic resonance imaging correlation. (orig.)

  6. Evidence for altered basal ganglia-brainstem connections in cervical dystonia.

    Directory of Open Access Journals (Sweden)

    Anne J Blood

    Full Text Available There has been increasing interest in the interaction of the basal ganglia with the cerebellum and the brainstem in motor control and movement disorders. In addition, it has been suggested that these subcortical connections with the basal ganglia may help to coordinate a network of regions involved in mediating posture and stabilization. While studies in animal models support a role for this circuitry in the pathophysiology of the movement disorder dystonia, thus far, there is only indirect evidence for this in humans with dystonia.In the current study we investigated probabilistic diffusion tractography in DYT1-negative patients with cervical dystonia and matched healthy control subjects, with the goal of showing that patients exhibit altered microstructure in the connectivity between the pallidum and brainstem. The brainstem regions investigated included nuclei that are known to exhibit strong connections with the cerebellum. We observed large clusters of tractography differences in patients relative to healthy controls, between the pallidum and the brainstem. Tractography was decreased in the left hemisphere and increased in the right hemisphere in patients, suggesting a potential basis for the left/right white matter asymmetry we previously observed in focal dystonia patients.These findings support the hypothesis that connections between the basal ganglia and brainstem play a role in the pathophysiology of dystonia.

  7. Optimal technique of linear accelerator-based stereotactic radiosurgery for tumors adjacent to brainstem.

    Science.gov (United States)

    Chang, Chiou-Shiung; Hwang, Jing-Min; Tai, Po-An; Chang, You-Kang; Wang, Yu-Nong; Shih, Rompin; Chuang, Keh-Shih

    2016-01-01

    Stereotactic radiosurgery (SRS) is a well-established technique that is replacing whole-brain irradiation in the treatment of intracranial lesions, which leads to better preservation of brain functions, and therefore a better quality of life for the patient. There are several available forms of linear accelerator (LINAC)-based SRS, and the goal of the present study is to identify which of these techniques is best (as evaluated by dosimetric outcomes statistically) when the target is located adjacent to brainstem. We collected the records of 17 patients with lesions close to the brainstem who had previously been treated with single-fraction radiosurgery. In all, 5 different lesion catalogs were collected, and the patients were divided into 2 distance groups-1 consisting of 7 patients with a target-to-brainstem distance of less than 0.5cm, and the other of 10 patients with a target-to-brainstem distance of ≥ 0.5 and linear accelerator is only 1 modality can to establish for SRS treatment. Based on statistical evidence retrospectively, we recommend VMAT as the optimal technique for delivering treatment to tumors adjacent to brainstem. Copyright © 2016 American Association of Medical Dosimetrists. All rights reserved.

  8. Abnormal trajectories in cerebellum and brainstem volumes in carriers of the fragile X premutation.

    Science.gov (United States)

    Wang, Jun Yi; Hessl, David; Hagerman, Randi J; Simon, Tony J; Tassone, Flora; Ferrer, Emilio; Rivera, Susan M

    2017-07-01

    Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder typically affecting male premutation carriers with 55-200 CGG trinucleotide repeat expansions in the FMR1 gene after age 50. The aim of this study was to examine whether cerebellar and brainstem changes emerge during development or aging in late life. We retrospectively analyzed magnetic resonance imaging scans from 322 males (age 8-81 years). Volume changes in the cerebellum and brainstem were contrasted with those in the ventricles and whole brain. Compared to the controls, premutation carriers without FXTAS showed significantly accelerated volume decrease in the cerebellum and whole brain, flatter inverted U-shaped trajectory of the brainstem, and larger ventricles. Compared to both older controls and premutation carriers without FXTAS, carriers with FXTAS exhibited significant volume decrease in the cerebellum and whole brain and accelerated volume decrease in the brainstem. We therefore conclude that cerebellar and brainstem volumes were likely affected during both development and progression of neurodegeneration in premutation carriers, suggesting that interventions may need to start early in adulthood to be most effective. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Correlation of Acute and Late Brainstem Toxicities With Dose-Volume Data for Pediatric Patients With Posterior Fossa Malignancies

    Energy Technology Data Exchange (ETDEWEB)

    Nanda, Ronica H., E-mail: rhazari@emory.edu [Department of Radiation Oncology, Winship Cancer Institute, Emory University College of Medicine, Atlanta, Georgia (United States); Ganju, Rohit G.; Schreibmann, Edward [Department of Radiation Oncology, Winship Cancer Institute, Emory University College of Medicine, Atlanta, Georgia (United States); Chen, Zhengjia; Zhang, Chao [Department of Biostatistics and Bioinformatics Shared Resource, Winship Cancer Institute, Emory University Rollins School of Public Health, Atlanta, Georgia (United States); Jegadeesh, Naresh; Cassidy, Richard; Deng, Claudia; Eaton, Bree R.; Esiashvili, Natia [Department of Radiation Oncology, Winship Cancer Institute, Emory University College of Medicine, Atlanta, Georgia (United States)

    2017-06-01

    Purpose: Radiation-induced brainstem toxicity after treatment of pediatric posterior fossa malignancies is incompletely understood, especially in the era of intensity modulated radiation therapy (IMRT). The rates of, and predictive factors for, brainstem toxicity after photon RT for posterior fossa tumors were examined. Methods and Materials: After institutional review board approval, 60 pediatric patients treated at our institution for nonmetastatic infratentorial ependymoma and medulloblastoma with IMRT were included in the present analysis. Dosimetric variables, including the mean and maximum dose to the brainstem, the dose to 10% to 90% of the brainstem (in 10% increments), and the volume of the brainstem receiving 40, 45, 50, and 55 Gy were recorded for each patient. Acute (onset within 3 months) and late (>3 months of RT completion) RT-induced brainstem toxicities with clinical and radiographic correlates were scored using Common Terminology Criteria for Adverse Events, version 4.0. Results: Patients aged 1.4 to 21.8 years underwent IMRT or volumetric arc therapy postoperatively to the posterior fossa or tumor bed. At a median clinical follow-up period of 2.8 years, 14 patients had developed symptomatic brainstem toxicity (crude incidence 23.3%). No correlation was found between the dosimetric variables examined and brainstem toxicity. Vascular injury or ischemia showed a strong trend toward predicting brainstem toxicity (P=.054). Patients with grade 3 to 5 brainstem toxicity had undergone treatment to significant volumes of the posterior fossa. Conclusion: The results of the present series demonstrate a low, but not negligible, risk of brainstem radiation necrosis for pediatric patients with posterior fossa malignancies treated with IMRT. No specific dose-volume correlations were identified; however, modern treatment volumes might help limit the incidence of severe toxicity. Additional work investigating inherent biologic sensitivity might also provide

  10. Diverse Intrinsic Properties Shape Functional Phenotype of Low-Frequency Neurons in the Auditory Brainstem

    Directory of Open Access Journals (Sweden)

    Hui Hong

    2018-06-01

    Full Text Available In the auditory system, tonotopy is the spatial arrangement of where sounds of different frequencies are processed. Defined by the organization of neurons and their inputs, tonotopy emphasizes distinctions in neuronal structure and function across topographic gradients and is a common feature shared among vertebrates. In this study we characterized action potential firing patterns and ion channel properties from neurons located in the extremely low-frequency region of the chicken nucleus magnocellularis (NM, an auditory brainstem structure. We found that NM neurons responsible for encoding the lowest sound frequencies (termed NMc neurons have enhanced excitability and fired bursts of action potentials to sinusoidal inputs ≤10 Hz; a distinct firing pattern compared to higher-frequency neurons. This response property was due to lower amounts of voltage dependent potassium (KV conductances, unique combination of KV subunits and specialized sodium (NaV channel properties. Particularly, NMc neurons had significantly lower KV1 and KV3 currents, but higher KV2 current. NMc neurons also showed larger and faster transient NaV current (INaT with different voltage dependence of inactivation from higher-frequency neurons. In contrast, significantly smaller resurgent sodium current (INaR was present in NMc with kinetics and voltage dependence that differed from higher-frequency neurons. Immunohistochemistry showed expression of NaV1.6 channel subtypes across the tonotopic axis. However, various immunoreactive patterns were observed between regions, likely underlying some tonotopic differences in INaT and INaR. Finally, using pharmacology and computational modeling, we concluded that KV3, KV2 channels and INaR work synergistically to regulate burst firing in NMc.

  11. Increased brainstem perfusion, but no blood-brain barrier disruption, during attacks of migraine with aura

    DEFF Research Database (Denmark)

    Hougaard, Anders; Amin, Faisal M; Christensen, Casper E

    2017-01-01

    symptoms are related to the headache phase of migraine. Animal studies suggest that cortical spreading depression, the likely mechanism of migraine aura, causes disruption of the blood-brain barrier and noxious stimulation of trigeminal afferents leading to activation of brainstem nuclei and triggering...... of migraine headache. We used the sensitive and validated technique of dynamic contrast-enhanced high-field magnetic resonance imaging to simultaneously investigate blood-brain barrier permeability and tissue perfusion in the brainstem (at the level of the lower pons), visual cortex, and brain areas......-free day. The mean time from attack onset to scanning was 7.6 h. We found increased brainstem perfusion bilaterally during migraine with aura attacks. Perfusion also increased in the visual cortex and posterior white matter following migraine aura. We found no increase in blood-brain barrier permeability...

  12. Stress-induced activation of the brainstem Bcl-xL gene expression in rats treated with fluoxetine: correlations with serotonin metabolism and depressive-like behavior.

    Science.gov (United States)

    Shishkina, Galina T; Kalinina, Tatyana S; Berezova, Inna V; Dygalo, Nikolay N

    2012-01-01

    Mechanisms underlying stress-induced depression and antidepressant drug action were shown to involve alterations in serotonergic (5-HT) neurotransmission and expression of genes coding for proteins associated with neurotrophic signaling pathways and cell-survival in the hippocampus and cortex. Expression of these genes in the brainstem containing 5-HT neurons may also be related to vulnerability or resilience to stress-related psychopathology. Here we investigated 5-HT markers and expression of genes for Brain-Derived Neurotrophic Factor (BDNF) and apoptotic proteins in the brainstem in relation to swim stress-induced behavioral despair. We found that anti-apoptotic Bcl-xL gene is sensitive to stress during the course of fluoxetine administration. Responsiveness of this gene to stress appeared concomitantly with an antidepressant-like effect of fluoxetine in the forced swim test. Bcl-xL transcript levels showed negative correlations with duration of immobility in the test and 5-HT turnover in the brainstem. In contrast, BDNF and pro-apoptotic protein Bax mRNA levels were unchanged by either fluoxetine or stress, suggesting specificity of Bcl-xL gene responses to these treatments. We also found that the levels of mRNAs for tryptophan hydroxylase-2 (TPH2) and 5-HT transporter (5-HTT) were significantly down-regulated following prolonged treatment with fluoxetine, but were not affected by stress. Unlike TPH2 and 5-HTT, 5-HT1A receptor mRNA levels were not altered by fluoxetine but significantly increased in response to swim stress. These data show that long-term fluoxetine treatment leads to changes in 5-HT and Bcl-xL responses to stress associated with antidepressant-like effects of the drug. This article is part of a Special Issue entitled 'Anxiety and Depression'. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Right-sided dominance of the bilateral vestibular system in the upper brainstem and thalamus.

    Science.gov (United States)

    Dieterich, Marianne; Kirsch, V; Brandt, T

    2017-10-01

    MRI diffusion tensor imaging tractography was performed on the bilateral vestibular brainstem pathways, which run from the vestibular nuclei via the paramedian and posterolateral thalamic subnuclei to the parieto-insular vestibular cortex. Twenty-one right-handed healthy subjects participated. Quantitative analysis revealed a rope-ladder-like system of vestibular pathways in the brainstem with crossings at pontine and mesencephalic levels. Three structural types of right-left fiber distributions could be delineated: (1) evenly distributed pathways at the lower pontine level from the vestibular nuclei to the pontine crossing, (2) a moderate, pontomesencephalic right-sided lateralization between the pontine and mesencephalic crossings, and (3) a further increase of the right-sided lateralization above the mesencephalic crossing leading to the thalamic vestibular subnuclei. The increasing lateralization along the brainstem was the result of an asymmetric number of pontine and mesencephalic crossing fibers which was higher for left-to-right crossings. The dominance of the right vestibular meso-diencephalic circuitry in right-handers corresponds to the right-hemispheric dominance of the vestibular cortical network. The structural asymmetry apparent in the upper brainstem might be interpreted in relation to the different functions of the vestibular system depending on their anatomical level: a symmetrical sensorimotor reflex control of eye, head, and body mediated by the lower brainstem; a lateralized right-sided upper brainstem-thalamic function as part of the dominant right-sided cortical/subcortical vestibular system that enables a global percept of body motion and orientation in space.

  14. The maturational process of the auditory system in the first year of life characterized by brainstem auditory evoked potentials

    Directory of Open Access Journals (Sweden)

    Raquel Beltrão Amorim

    2009-01-01

    Full Text Available The study of brainstem auditory evoked potentials (BAEP allows obtaining the electrophysiological activity generated in the cochlear nerve to the inferior colliculus. In the first months of life, a period of greater neuronal plasticity, important changes are observed in the absolute latency and inter-peak intervals of BAEP, which occur up to the completion of the maturational process, around 18 months of life in full-term newborns, when the response is similar to that of adults. OBJECTIVE: The goal of this study was to establish normal values of absolute latencies for waves I, III and V and inter-peak intervals I-III, III-V and I-V of the BAEP performed in full-term infants attending the Infant Hearing Health Program of the Speech-Language Pathology and Audiology Course at Bauru School of Dentistry, Brazil, with no risk history for hearing impairment. MATERIAL AND METHODS: The stimulation parameters were: rarefaction click stimulus presented by the 3ª insertion phone, intensity of 80 dBnHL and a rate of 21.1 c/s, band-pass filter of 30 and 3,000 Hz and average of 2,000 stimuli. A sample of 86 infants was first divided according to their gestational age in preterm (n=12 and full-term (n=74, and then according to their chronological age in three periods: P1: 0 to 29 days (n=46, P2: 30 days to 5 months 29 days (n=28 and P3: above 6 months (n= 12. RESULTS: The absolute latency of wave I was similar to that of adults, generally in the 1st month of life, demonstrating a complete process maturity of the auditory nerve. For waves III and V, there was a gradual decrease of absolute latencies with age, characterizing the maturation of axons and synaptic mechanisms in the brainstem level. CONCLUSION: Age proved to be a determining factor in the absolute latency of the BAEP components, especially those generated in the brainstem, in the first year of life.

  15. [Forensic application of brainstem auditory evoked potential in patients with brain concussion].

    Science.gov (United States)

    Zheng, Xing-Bin; Li, Sheng-Yan; Huang, Si-Xing; Ma, Ke-Xin

    2008-12-01

    To investigate changes of brainstem auditory evoked potential (BAEP) in patients with brain concussion. Nineteen patients with brain concussion were studied with BAEP examination. The data was compared to the healthy persons reported in literatures. The abnormal rate of BAEP for patients with brain concussion was 89.5%. There was a statistically significant difference between the abnormal rate of patients and that of healthy persons (Pconcussion was 73.7%, indicating dysfunction of the brainstem in those patients. BAEP might be helpful in forensic diagnosis of brain concussion.

  16. Abréviations

    OpenAIRE

    2013-01-01

    A ACCT – Agence de Coopération Culturelle et TechniqueACP – Afrique, Caraïbes, PacifiqueAELE – Association européenne de libre-échangeAFF – Administration fédérale des financesAGE – Accords généraux d’empruntsAI – Amnesty internationalAID – Agence internationale pour le développement (IDA)AIE – Agence internationale de l’énergieALENA – Accord de libre-échange nord-américainAMF – Arrangement multifibreAMGI – Agence multilatérale de garantie des risques à l’investissementAOSIS – Association des...

  17. Abréviations

    OpenAIRE

    2013-01-01

    A AELE – Association européenne de libre échangeAIE – Agence internationale de l’énergieAIEA – Agence internationale de l’énergie atomiqueAMF – Arrangement concernant le commerce international des textiles, dit Arrangement multifibresAPD – Aide publique au développement B BAD – Banque africaine de développementBNS – Banque nationale suisse C CAD – Comité d’aide au développement de l’OCDE ; regroupe les pays suivants Australie, Autriche, Belgique, Canada, Danemark, Finlande, France, Allemagne,...

  18. Abréviations

    OpenAIRE

    2012-01-01

    A ACCT — Agence de Coopération Culturelle et TechniqueACP — Afrique, Caraïbes, PacifiqueAELE — Association européenne de libre-échangeAFF — Administration fédérale des financesAGE — Accords généraux d'empruntsAI — Amnesty internationalAID — Agence internationale pour le développement (IDA)AIE — Agence internationale de l'énergieALENA — Accord de libre-échange nord-américainAMF — Arrangement multifibreAMGI — Agence multilatérale de garantie des risques à l'investissementAPD — Aide publique au ...

  19. Abréviations

    OpenAIRE

    2013-01-01

    AREU Afghanistan Research and Evaluation Unit BCS Badloon Consultancy and Civil Society BHC Basic Health Clinic BPRM Bureau of Populations, Movement and Refugees CSO Central Statistics Organization DCDA Dehsabz-Barikab City Development Authority IDKA Independent Directorate of Kuchi Affairs IDLG Independent Directorate of Local Governance IDP Internally Displaced Persons IOM International Organization for Migration ...

  20. Abréviations

    Directory of Open Access Journals (Sweden)

    2013-06-01

    Full Text Available AREU Afghanistan Research and Evaluation Unit BCS Badloon Consultancy and Civil Society BHC Basic Health Clinic BPRM Bureau of Populations, Movement and Refugees CSO Central Statistics Organization DCDA Dehsabz-Barikab City Development Authority IDKA Independent Directorate of Kuchi Affairs IDLG Independent Directorate of Local Governance IDP Internally Displaced Persons IOM International Organization for Migration ...

  1. Abréviations

    OpenAIRE

    2014-01-01

    ACB Analyse coûts/bénéfices ARP Analyse du risque phytosanitaire CDB Convention sur la diversité biologique CGAPS Coordinating Group on Alien Pest Species CIPV Convention internationale pour la protection des végétaux CITES Convention internationale sur les espèces menacées CRC Cooperative Research Center (CRC) for Australian Weed Management DAE Direction des affaires économiques Davar Direction des affaires vétérinaire, alimentaire et rurale DDE-E Direction du développement économique et de ...

  2. Improved Transient Response Estimations in Predicting 40 Hz Auditory Steady-State Response Using Deconvolution Methods

    Directory of Open Access Journals (Sweden)

    Xiaodan Tan

    2017-12-01

    Full Text Available The auditory steady-state response (ASSR is one of the main approaches in clinic for health screening and frequency-specific hearing assessment. However, its generation mechanism is still of much controversy. In the present study, the linear superposition hypothesis for the generation of ASSRs was investigated by comparing the relationships between the classical 40 Hz ASSR and three synthetic ASSRs obtained from three different templates for transient auditory evoked potential (AEP. These three AEPs are the traditional AEP at 5 Hz and two 40 Hz AEPs derived from two deconvolution algorithms using stimulus sequences, i.e., continuous loop averaging deconvolution (CLAD and multi-rate steady-state average deconvolution (MSAD. CLAD requires irregular inter-stimulus intervals (ISIs in the sequence while MSAD uses the same ISIs but evenly-spaced stimulus sequences which mimics the classical 40 Hz ASSR. It has been reported that these reconstructed templates show similar patterns but significant difference in morphology and distinct frequency characteristics in synthetic ASSRs. The prediction accuracies of ASSR using these templates show significant differences (p < 0.05 in 45.95, 36.28, and 10.84% of total time points within four cycles of ASSR for the traditional, CLAD, and MSAD templates, respectively, as compared with the classical 40 Hz ASSR, and the ASSR synthesized from the MSAD transient AEP suggests the best similarity. And such a similarity is also demonstrated at individuals only in MSAD showing no statistically significant difference (Hotelling's T2 test, T2 = 6.96, F = 0.80, p = 0.592 as compared with the classical 40 Hz ASSR. The present results indicate that both stimulation rate and sequencing factor (ISI variation affect transient AEP reconstructions from steady-state stimulation protocols. Furthermore, both auditory brainstem response (ABR and middle latency response (MLR are observed in contributing to the composition of ASSR but

  3. Population calcium imaging of spontaneous respiratory and novel motor activity in the facial nucleus and ventral brainstem in newborn mice

    DEFF Research Database (Denmark)

    Persson, Karin; Rekling, Jens C

    2011-01-01

    The brainstem contains rhythm and pattern forming circuits, which drive cranial and spinal motor pools to produce respiratory and other motor patterns. Here we used calcium imaging combined with nerve recordings in newborn mice to reveal spontaneous population activity in the ventral brainstem...... and in the facial nucleus. In Fluo-8AM loaded brainstem-spinal cord preparations, respiratory activity on cervical nerves was synchronized with calcium signals at the ventrolateral brainstem surface. Individual ventrolateral neurons at the level of the parafacial respiratory group showed perfect or partial...... synchrony with respiratory nerve bursts. In brainstem-spinal cord preparations, cut at the level of the mid-facial nucleus, calcium signals were recorded in the dorsal, lateral and medial facial subnuclei during respiratory activity. Strong activity initiated in the dorsal subnucleus, followed by activity...

  4. ¡Abre los ojos! Un proyecto de mejora educativa para la prevención de drogas en adolescentes

    Directory of Open Access Journals (Sweden)

    Cecilia Mª AZORÍN ABELLÁN

    2016-01-01

    Full Text Available La Educación para la Salud (EpS es un tema transversal del currículo que adolece de propuestas didácticas novedosas para la intervención pedagógica. El objetivo del trabajo que se presenta es poner en marcha un plan de mejora para la prevención de drogadicciones en adolescentes. Para ello, se ha trabajado con un total de 142 estudiantes de 3º de Educación Secundaria Obligatoria (ESO con edades comprendidas entre los 14 y los 16 años que cursan estudios en el Instituto “Francisco Salzillo” de la localidad de Alcantarilla (Murcia. Concretamente, este artículo da luz al Proyecto ¡Abre los ojos!, que forma parte del Plan de Acción Tutorial (PAT y del Plan de Mejora para la Prevención de Drogas (PMPD propuesto desde el Departamento de Orientación. Se exponen ad hoc las actividades implementadas durante las 3 sesiones trabajadas con cada uno de los 6 grupos-clase escolarizados en este nivel. Haciendo uso de la reflexión-acción, el alumnado ha desarrollado una conciencia crítica acerca de los riesgos que entraña para la salud el consumo de drogas. Asimismo, mediante la técnica de grupos de discusión los discentes han realizado un interesante debate cuyas ideas han sido organizadas en torno a tres aspectos clave: causas por las que se empieza a consumir, cómo evitar caer en las drogas, y alternativas de ocio y tiempo libre para una vida saludable. Finalmente, se especifica la necesidad de abordar tareas de prevención en los centros educativos así como de facilitar información y de resolver las inquietudes de los jóvenes acerca de esta temática.

  5. Auditory Brainstem Implantation in Chinese Patients With Neurofibromatosis Type II: The Hong Kong Experience.

    Science.gov (United States)

    Thong, Jiun Fong; Sung, John K K; Wong, Terence K C; Tong, Michael C F

    2016-08-01

    To describe our experience and outcomes of auditory brainstem implantation (ABI) in Chinese patients with Neurofibromatosis Type II (NF2). Retrospective case review. Tertiary referral center. Patients with NF2 who received ABIs. Between 1997 and 2014, eight patients with NF2 received 9 ABIs after translabyrinthine removal of their vestibular schwannomas. One patient did not have auditory response using the ABI after activation. Environmental sounds could be differentiated by six (75%) patients after 6 months of ABI use (mean score 46% [range 28-60%]), and by five (63%) patients after 1 year (mean score 57% [range 36-76%]) and 2 years of ABI use (mean score 48% [range 24-76%]). Closed-set word identification was possible in four (50%) patients after 6 months (mean score 39% [range 12-72%]), 1 year (mean score 68% [range 48-92%]), and 2 years of ABI use (mean score 62% [range 28-100%]). No patient demonstrated open-set sentence recognition in quiet in the ABI-only condition. However, the use of ABI together with lip-reading conferred an improvement over lip-reading alone in open-set sentence recognition scores in two (25%) patients after 6 months of ABI use (mean improvement 46%), and five (63%) patients after 1 year (mean improvement 25%) and 2 years of ABI use (mean improvement 28%). At 2 years postoperatively, three (38%) patients remained ABI users. This is the only published study to date examining ABI outcomes in Cantonese-speaking Chinese NF2 patients and the data seems to show poorer outcomes compared with English-speaking and other nontonal language-speaking NF2 patients. Environmental sound awareness and lip-reading enhancement are the main benefits observed in our patients. More work is needed to improve auditory implant speech-processing strategies for tonal languages and these advancements may yield better speech perception outcomes in the future.

  6. Subcortical encoding of speech cues in children with attention deficit hyperactivity disorder.

    Science.gov (United States)

    Jafari, Zahra; Malayeri, Saeed; Rostami, Reza

    2015-02-01

    There is little information about processing of nonspeech and speech stimuli at the subcortical level in individuals with attention deficit hyperactivity disorder (ADHD). The auditory brainstem response (ABR) provides information about the function of the auditory brainstem pathways. We aim to investigate the subcortical function in neural encoding of click and speech stimuli in children with ADHD. The subjects include 50 children with ADHD and 34 typically developing (TD) children between the ages of 8 and 12 years. Click ABR (cABR) and speech ABR (sABR) with 40 ms synthetic /da/ syllable stimulus were recorded. Latencies of cABR in waves of III and V and duration of V-Vn (P⩽0.027), and latencies of sABR in waves A, D, E, F and O and duration of V-A (P⩽0.034) were significantly longer in children with ADHD than in TD children. There were no apparent differences in components the sustained frequency following response (FFR). We conclude that children with ADHD have deficits in temporal neural encoding of both nonspeech and speech stimuli. There is a common dysfunction in the processing of click and speech stimuli at the brainstem level in children with suspected ADHD. Copyright © 2015. Published by Elsevier Ireland Ltd.

  7. CD8+ T Cells Induce Fatal Brainstem Pathology during Cerebral Malaria via Luminal Antigen-Specific Engagement of Brain Vasculature.

    Directory of Open Access Journals (Sweden)

    Phillip A Swanson

    2016-12-01

    Full Text Available Cerebral malaria (CM is a severe complication of Plasmodium falciparum infection that results in thousands of deaths each year, mostly in African children. The in vivo mechanisms underlying this fatal condition are not entirely understood. Using the animal model of experimental cerebral malaria (ECM, we sought mechanistic insights into the pathogenesis of CM. Fatal disease was associated with alterations in tight junction proteins, vascular breakdown in the meninges / parenchyma, edema, and ultimately neuronal cell death in the brainstem, which is consistent with cerebral herniation as a cause of death. At the peak of ECM, we revealed using intravital two-photon microscopy that myelomonocytic cells and parasite-specific CD8+ T cells associated primarily with the luminal surface of CNS blood vessels. Myelomonocytic cells participated in the removal of parasitized red blood cells (pRBCs from cerebral blood vessels, but were not required for the disease. Interestingly, the majority of disease-inducing parasite-specific CD8+ T cells interacted with the lumen of brain vascular endothelial cells (ECs, where they were observed surveying, dividing, and arresting in a cognate peptide-MHC I dependent manner. These activities were critically dependent on IFN-γ, which was responsible for activating cerebrovascular ECs to upregulate adhesion and antigen-presenting molecules. Importantly, parasite-specific CD8+ T cell interactions with cerebral vessels were impaired in chimeric mice rendered unable to present EC antigens on MHC I, and these mice were in turn resistant to fatal brainstem pathology. Moreover, anti-adhesion molecule (LFA-1 / VLA-4 therapy prevented fatal disease by rapidly displacing luminal CD8+ T cells from cerebrovascular ECs without affecting extravascular T cells. These in vivo data demonstrate that parasite-specific CD8+ T cell-induced fatal vascular breakdown and subsequent neuronal death during ECM is associated with luminal, antigen

  8. Developmental study of vitamin C distribution in children's brainstems by immunohistochemistry.

    Science.gov (United States)

    Coveñas, R; González-Fuentes, J; Rivas-Infante, E; Lagartos-Donate, M J; Mangas, A; Geffard, M; Arroyo-Jiménez, M M; Cebada-Sánchez, S; Insausti, R; Marcos, P

    2015-09-01

    Vitamin C (Vit C) is an important antioxidant, exerts powerful neuroprotective brain effects and plays a role in neuronal development and maturation. Vit C is present in brain tissue at higher concentrations than in other organs, but its detailed distribution in brain is unknown. Immunohistochemical detection of this vitamin has been performed by using a highly specific antibody against Vit C. The aim of the present work was to analyze the distribution of Vit C in children's brainstems during postnatal development, comparing two groups of ages: younger and older than one year of life. In general, the same areas showing neurons with Vit C in young cases are also immunostained at older ages. The distribution of neurons containing Vit C was broader in the brainstems of older children, suggesting that brainstem neurons maintain or even increase their ability to retain Vit C along the life span. Immunohistochemical labeling revealed only cell bodies containing this vitamin, and no immunoreactive fibers were observed. The distribution pattern of Vit C in children's brainstems suggests a possible role of Vit C in brain homeostatic regulation. In addition, the constant presence of Vit C in neurons of locus coeruleus supports the important role of Vit C in noradrenaline synthesis, which seemed to be maintained along postnatal development. Copyright © 2015 Elsevier GmbH. All rights reserved.

  9. Stereotactic radiosurgery for brainstem metastases: Survival, tumor control, and patient outcomes

    International Nuclear Information System (INIS)

    Hussain, Aamir; Brown, Paul D.; Stafford, Scott L.; Pollock, Bruce E.

    2007-01-01

    Purpose: Patients with brainstem metastases have limited treatment options. In this study, we reviewed outcomes after stereotactic radiosurgery (SRS) in the management of patients with brainstem metastases. Methods and Materials: Records were reviewed of 22 consecutive patients presenting with brainstem metastases who underwent SRS. The most frequent primary malignancy was the lung (n = 11), followed by breast (n = 3) and kidney (n = 2). Three patients (14%) also underwent whole-brain radiation therapy (WBRT). The median tumor volume was 0.9 mL (range, 0.1-3.3 mL); the median tumor margin dose was 16 Gy (range, 14-23 Gy). Results: Median survival time after SRS was 8.5 months. Although local tumor control was achieved in all patients with imaging follow-up (n = 19), 5 patients died from development and progression of new brain metastases. Two patients (9%) had symptom improvement after SRS, whereas 1 patient (5%) developed a new hemiparesis after SRS. Conclusions: Radiosurgery is safe and provides a high local tumor control rate for patients with small brainstem metastases. Patients with limited systemic disease and good performance status should be strongly considered for SRS

  10. Stereotactic radiosurgery for deep intracranial arteriovenous malformations, part 1: Brainstem arteriovenous malformations.

    Science.gov (United States)

    Cohen-Inbar, Or; Ding, Dale; Chen, Ching-Jen; Sheehan, Jason P

    2016-02-01

    The management of brainstem arteriovenous malformations (AVM) are one of the greatest challenges encountered by neurosurgeons. Brainstem AVM have a higher risk of hemorrhage compared to AVM in other locations, and rupture of these lesions commonly results in devastating neurological morbidity and mortality. The potential morbidity associated with currently available treatment modalities further compounds the complexity of decision making for affected patients. Stereotactic radiosurgery (SRS) has an important role in the management of brainstem AVM. SRS offers acceptable obliteration rates with lower risks of hemorrhage occurring during the latency period. Complex nidal architecture requires a multi-disciplinary treatment approach. Nidi partly involving subpial/epipial regions of the dorsal midbrain or cerebellopontine angle should be considered for a combination of endovascular embolization, micro-surgical resection and SRS. Considering the fact that incompletely obliterated lesions (even when reduced in size) could still cause lethal hemorrhages, additional treatment, including repeat SRS and surgical resection should be considered when complete obliteration is not achieved by first SRS. Patients with brainstem AVM require continued clinical and radiological observation and follow-up after SRS, well after angiographic obliteration has been confirmed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Two oculomotor-related areas of the brainstem project to the dorsolateral periaqueductal gray.

    NARCIS (Netherlands)

    Klop, E.M.; Mouton, Leonora J.; Holstege, Gert

    2005-01-01

    The dorsolateral column of the periaqueductal gray (PAGdl) is usually associated with defensive behavior, but how this is brought about is not yet fully understood. In order to elucidate the function of PAGdl, its afferents from the brainstem were investigated in cats. Retrograde tracing results

  12. Normal development of brainstem in childhood. Measurement of the area on mid-sagittal MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kutomi, Kimiko [Teikyo Univ., Tokyo (Japan). Faculty of Medicine

    2005-05-01

    Developmental abnormality of brainstem is shown in pediatric patients with mental retardation, autism, periventricular leukomalacia, neurodegenerative disease, and so on. Our purpose here is to clarify the normal developmental pattern of the brainstem. We measured the area of tectum, midbrain tegmentum, pons, basis pontis and pontine tegmentum on mid-sagittal MR images in 111 children (newborn to 20 year old). Different growth patterns were shown in all parts of the brainstem. Tectum showed a subtle increase in area from the newborn to adult period, while midbrain tegmentum and pontine tegmenturn showed a mild and gradual increase in area. Pons and pontine tegmentum showed a rapid and prominent increase in area from newborn to infant period and gradual increase in area until the adult period. These different growth patterns seemed to be consistent with differences in the myelination cycles of the neuronal fibers, maturation of the nuclei and proliferation of glial cells in each part of the brainstem. Mid-sagittal MR imaging of the head is accurate and reproducible and is used conveniently in routine head MR study, making it very useful for the diagnosis of many central nervous diseases and anomalies. We believe that this new milestone provided in this study will be helpful in distinguishing normal children from those that have neurodegenerative disorders. (author)

  13. Normal development of brainstem in childhood. Measurement of the area on mid-sagittal MR imaging

    International Nuclear Information System (INIS)

    Kutomi, Kimiko

    2005-01-01

    Developmental abnormality of brainstem is shown in pediatric patients with mental retardation, autism, periventricular leukomalacia, neurodegenerative disease, and so on. Our purpose here is to clarify the normal developmental pattern of the brainstem. We measured the area of tectum, midbrain tegmentum, pons, basis pontis and pontine tegmentum on mid-sagittal MR images in 111 children (newborn to 20 year old). Different growth patterns were shown in all parts of the brainstem. Tectum showed a subtle increase in area from the newborn to adult period, while midbrain tegmentum and pontine tegmenturn showed a mild and gradual increase in area. Pons and pontine tegmentum showed a rapid and prominent increase in area from newborn to infant period and gradual increase in area until the adult period. These different growth patterns seemed to be consistent with differences in the myelination cycles of the neuronal fibers, maturation of the nuclei and proliferation of glial cells in each part of the brainstem. Mid-sagittal MR imaging of the head is accurate and reproducible and is used conveniently in routine head MR study, making it very useful for the diagnosis of many central nervous diseases and anomalies. We believe that this new milestone provided in this study will be helpful in distinguishing normal children from those that have neurodegenerative disorders. (author)

  14. Effects of brainstem lesions on the masseter inhibitory reflex. Functional mechanisms of reflex pathways

    NARCIS (Netherlands)

    Ongerboer de Visser, B. W.; Cruccu, G.; Manfredi, M.; Koelman, J. H.

    1990-01-01

    The masseter inhibitory reflex (MIR) was investigated in 16 patients with localized brainstem lesions involving the trigeminal system. The MIR consists of two phases of EMG silence (S1 and S2) evoked by stimulation of the mental nerve during maximal clenching of the teeth. The extent of the lesions

  15. The human premotor oculomotor brainstem system - can it help to understand oculomotor symptoms in Huntington's disease?

    NARCIS (Netherlands)

    Rueb, U.; Heinsen, H.; Brunt, E. R.; Landwehrmeyer, B.; Den Dunnen, W. F. A.; Gierga, K.; Deller, T.

    Recent progress in oculomotor research has enabled new insights into the functional neuroanatomy of the human premotor oculomotor brainstem network. In the present review, we provide an overview of its functional neuroanatomy and summarize the broad range of oculomotor dysfunctions that may occur in

  16. Relationship between brainstem neurodegeneration and clinical impairment in traumatic spinal cord injury

    Directory of Open Access Journals (Sweden)

    Patrick Grabher

    2017-01-01

    Conclusion: Neurodegeneration, indicated by volume loss and myelin reductions, is evident in major brainstem pathways and nuclei following traumatic SCI; the magnitude of these changes relating to clinical impairment. Thus, quantitative MRI protocols offer new targets, which may be used as neuroimaging biomarkers in treatment trials.

  17. Identification of clinical target areas in the brainstem of prion‐infected mice

    Science.gov (United States)

    Mirabile, Ilaria; Jat, Parmjit S.; Brandner, Sebastian

    2015-01-01

    Aims While prion infection ultimately involves the entire brain, it has long been thought that the abrupt clinical onset and rapid neurological decline in laboratory rodents relates to involvement of specific critical neuroanatomical target areas. The severity and type of clinical signs, together with the rapid progression, suggest the brainstem as a candidate location for such critical areas. In this study we aimed to correlate prion pathology with clinical phenotype in order to identify clinical target areas. Method We conducted a comprehensive survey of brainstem pathology in mice infected with two distinct prion strains, which produce different patterns of pathology, in mice overexpressing prion protein (with accelerated clinical onset) and in mice in which neuronal expression was reduced by gene targeting (which greatly delays clinical onset). Results We identified specific brainstem areas that are affected by prion pathology during the progression of the disease. In the early phase of disease the locus coeruleus, the nucleus of the solitary tract, and the pre‐Bötzinger complex were affected by prion protein deposition. This was followed by involvement of the motor and autonomic centres of the brainstem. Conclusions Neurodegeneration in the locus coeruleus, the nucleus of the solitary tract and the pre‐Bötzinger complex predominated and corresponded to the manifestation of the clinical phenotype. Because of their fundamental role in controlling autonomic function and the overlap with clinical signs in sporadic Creutzfeldt–Jakob disease, we suggest that these nuclei represent key clinical target areas in prion diseases. PMID:25311251

  18. Boxing sparring complicated by an acute subdural haematoma and brainstem haemorrhage.

    Science.gov (United States)

    Hart, Michael G; Trivedi, Rikin A; Hutchinson, Peter J

    2012-10-01

    A professional boxer developed an acute subdural haematoma after boxing sparring. Despite timely surgical decompression, he had a poor overall outcome predominantly from a delayed brainstem haematoma. Magnetic resonance imaging (MRI) was used to elucidate the pathophysiology of the patients' injury and clinical condition.

  19. C68 from the Sulfolobus islandicus plasmid-virus pSSVx is a novel member of the AbrB-like transcription factor family

    DEFF Research Database (Denmark)

    Contursi, Patrizia; D'Ambrosio, Katia; Pirone, Luciano

    2011-01-01

    The genetic element pSSVx from Sulfolobus islandicus, strain REY15/4, is a hybrid between a plasmid and a fusellovirus. This plasmid-virus hybrid infects several species of the hyperthermophilic acidophilic crenarchaeon Sulfolobus. The open reading frame orfc68 of pSSVx encodes a 7.7 kDa protein...... factors, such as AbrB from Bacillus subtilis. Nevertheless, C68 constitutes a novel representative of this family because it shows several peculiar structural and functional features....

  20. Characterising Ageing in the Human Brainstem Using Quantitative Multimodal MRI Analysis

    Directory of Open Access Journals (Sweden)

    Christian eLambert

    2013-08-01

    Full Text Available Ageing is ubiquitous to the human condition. The MRI correlates of healthy ageing have been extensively investigated using a range of modalities, including volumetric MRI, quantitative MRI and DTI. Despite this, the reported brainstem related changes remain sparse. This is, in part, due to the technical and methodological limitations in quantitatively assessing and statistically analysing this region. By utilising a new method of brainstem segmentation, a large cohort of 100 healthy adults were assessed in this study for the effects of ageing within the human brainstem in vivo. Using quantitative MRI (qMRI, tensor based morphometry (TBM and voxel based quantification (VBQ, the volumetric and quantitative changes across healthy adults between 19-75 years were characterised. In addition to the increased R2* in substantia nigra corresponding to increasing iron deposition with age, several novel findings were reported in the current study. These include selective volumetric loss of the brachium conjunctivum, with a corresponding decrease in magnetisation transfer (MT and increase in proton density (PD, accounting for the previously described midbrain shrinkage. Additionally, we found increases in R1 and PD in several pontine and medullary structures. We consider these changes in the context of well-characterised, functional age-related changes, and propose potential biophysical mechanisms. This study provides detailed quantitative analysis of the internal architecture of the brainstem and provides a baseline for further studies of neurodegenerative diseases that are characterised by early, pre-clinical involvement of the brainstem, such as Parkinson’s and Alzheimer’s diseases.

  1. Robust Machine Learning-Based Correction on Automatic Segmentation of the Cerebellum and Brainstem.

    Science.gov (United States)

    Wang, Jun Yi; Ngo, Michael M; Hessl, David; Hagerman, Randi J; Rivera, Susan M

    2016-01-01

    Automated segmentation is a useful method for studying large brain structures such as the cerebellum and brainstem. However, automated segmentation may lead to inaccuracy and/or undesirable boundary. The goal of the present study was to investigate whether SegAdapter, a machine learning-based method, is useful for automatically correcting large segmentation errors and disagreement in anatomical definition. We further assessed the robustness of the method in handling size of training set, differences in head coil usage, and amount of brain atrophy. High resolution T1-weighted images were acquired from 30 healthy controls scanned with either an 8-channel or 32-channel head coil. Ten patients, who suffered from brain atrophy because of fragile X-associated tremor/ataxia syndrome, were scanned using the 32-channel head coil. The initial segmentations of the cerebellum and brainstem were generated automatically using Freesurfer. Subsequently, Freesurfer's segmentations were both manually corrected to serve as the gold standard and automatically corrected by SegAdapter. Using only 5 scans in the training set, spatial overlap with manual segmentation in Dice coefficient improved significantly from 0.956 (for Freesurfer segmentation) to 0.978 (for SegAdapter-corrected segmentation) for the cerebellum and from 0.821 to 0.954 for the brainstem. Reducing the training set size to 2 scans only decreased the Dice coefficient ≤0.002 for the cerebellum and ≤ 0.005 for the brainstem compared to the use of training set size of 5 scans in corrective learning. The method was also robust in handling differences between the training set and the test set in head coil usage and the amount of brain atrophy, which reduced spatial overlap only by segmentation and corrective learning provides a valuable method for accurate and efficient segmentation of the cerebellum and brainstem, particularly in large-scale neuroimaging studies, and potentially for segmenting other neural regions as

  2. Four cases with localized brain-stem lesion on CT scan following closed head injury

    International Nuclear Information System (INIS)

    Saeki, Naokatsu; Odaki, Masaru; Oka, Nobuo; Takase, Manabu; Ono, Junichi.

    1981-01-01

    Cases of primary brain-stem injury following closed head injury, verified by a CT scan, have been increasingly reported. However, most of them have other intracranial lesions in addition to the brain stem, resulting in a poor outcome. The CT scan of 200 cases with severe head injury-Araki's classification of types 3 and 4 - were analysed. Four cases out of them had localized brain-stem lesion without any other significant intracranial injury on a CT scan at the acute stage and had a better outcome than had previously been reported. In this analysis, these 4 cases were studied, and the CT findings, prognosis, and pathogenesis of the localized brain-stem injury were discussed. Follow-up CT of three cases, and taken one month or more later, showed diffuse cortical atrophy. This may indicate the presence of diffuse cerebral injury which could not be seen on CT scans at the acute stage. This atrophic change may also be related with the mechanism of posttraumatic conscious impairment and posttraumatic neurological deficits, such as mental symptoms and impairment of the higher cortical function. Shearing injury is a probable pathogenesis for this diffuse cortical injury. On the other hand, one case did not have any cortical atrophy on a follow-up CT scan. Therefore, this is a case with a localized primary brain-stem injury. Coup injury against the brain stem by a tentorial margin in a case with a small tentorial opening is a possible mechanism producing the localized brain-stem injury. (J.P.N.)

  3. 7 Tesla 22-channel wrap-around coil array for cervical spinal cord and brainstem imaging.

    Science.gov (United States)

    Zhang, Bei; Seifert, Alan C; Kim, Joo-Won; Borrello, Joseph; Xu, Junqian

    2017-10-01

    Increased signal-to-noise ratio and blood oxygenation level-dependent sensitivity at 7 Tesla (T) have the potential to enable high-resolution imaging of the human cervical spinal cord and brainstem. We propose a new two-panel radiofrequency coil design for these regions to fully exploit the advantages of ultra-high field. A two-panel array, containing four transmit/receive and 18 receive-only elements fully encircling the head and neck, was constructed following simulations demonstrating the B1+ and specific absorption rate (SAR) benefits of two-panel over one-panel arrays. This array was compared with a previously reported posterior-only array and tested for safety using a phantom. Its anatomical, functional, and diffusion MRI performance was demonstrated in vivo. The two-panel array produced more uniform B1+ across the brainstem and cervical spinal cord without compromising SAR, and achieved 70% greater receive sensitivity than the posterior-only array. The two-panel design enabled acceleration of R = 2 × 2 in two dimensions or R = 3 in a single dimension. High quality in vivo anatomical, functional, and diffusion images of the human cervical spinal cord and brainstem were acquired. We have designed and constructed a wrap-around coil array with excellent performance for cervical spinal cord and brainstem MRI at 7T, which enables simultaneous human cervical spinal cord and brainstem functional MRI. Magn Reson Med 78:1623-1634, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  4. Macrovascular Decompression of the Brainstem and Cranial Nerves: Evolution of an Anteromedial Vertebrobasilar Artery Transposition Technique.

    Science.gov (United States)

    Choudhri, Omar; Connolly, Ian D; Lawton, Michael T

    2017-08-01

    Tortuous and dolichoectatic vertebrobasilar arteries can impinge on the brainstem and cranial nerves to cause compression syndromes. Transposition techniques are often required to decompress the brainstem with dolichoectatic pathology. We describe our evolution of an anteromedial transposition technique and its efficacy in decompressing the brainstem and relieving symptoms. To present the anteromedial vertebrobasilar artery transposition technique for macrovascular decompression of the brainstem and cranial nerves. All patients who underwent vertebrobasilar artery transposition were identified from the prospectively maintained database of the Vascular Neurosurgery service, and their medical records were reviewed retrospectively. The extent of arterial displacement was measured pre- and postoperatively on imaging. Vertebrobasilar arterial transposition and macrovascular decompression was performed in 12 patients. Evolution in technique was characterized by gradual preference for the far-lateral approach, use of a sling technique with muslin wrap, and an anteromedial direction of pull on the vertebrobasilar artery with clip-assisted tethering to the clival dura. With this technique, mean lateral displacement decreased from 6.6 mm in the first half of the series to 3.8 mm in the last half of the series, and mean anterior displacement increased from 0.8 to 2.5 mm, with corresponding increases in satisfaction and relief of symptoms. Compressive dolichoectatic pathology directed laterally into cranial nerves and posteriorly into the brainstem can be corrected with anteromedial transposition towards the clivus. Our technique accomplishes this anteromedial transposition from an inferolateral surgical approach through the vagoaccessory triangle, with sling fixation to clival dura using aneurysm clips. Copyright © 2017 by the Congress of Neurological Surgeons

  5. Transcriptomic analysis of rice aleurone cells identified a novel abscisic acid response element.

    Science.gov (United States)

    Watanabe, Kenneth A; Homayouni, Arielle; Gu, Lingkun; Huang, Kuan-Ying; Ho, Tuan-Hua David; Shen, Qingxi J

    2017-09-01

    Seeds serve as a great model to study plant responses to drought stress, which is largely mediated by abscisic acid (ABA). The ABA responsive element (ABRE) is a key cis-regulatory element in ABA signalling. However, its consensus sequence (ACGTG(G/T)C) is present in the promoters of only about 40% of ABA-induced genes in rice aleurone cells, suggesting other ABREs may exist. To identify novel ABREs, RNA sequencing was performed on aleurone cells of rice seeds treated with 20 μM ABA. Gibbs sampling was used to identify enriched elements, and particle bombardment-mediated transient expression studies were performed to verify the function. Gene ontology analysis was performed to predict the roles of genes containing the novel ABREs. This study revealed 2443 ABA-inducible genes and a novel ABRE, designated as ABREN, which was experimentally verified to mediate ABA signalling in rice aleurone cells. Many of the ABREN-containing genes are predicted to be involved in stress responses and transcription. Analysis of other species suggests that the ABREN may be monocot specific. This study also revealed interesting expression patterns of genes involved in ABA metabolism and signalling. Collectively, this study advanced our understanding of diverse cis-regulatory sequences and the transcriptomes underlying ABA responses in rice aleurone cells. © 2017 John Wiley & Sons Ltd.

  6. Using Aesthetic Response, a Poetic Inquiry to Expand Knowing

    DEFF Research Database (Denmark)

    Gerge, Anna; Warja, Margareta; Pedersen, Inge Nygaard

    2017-01-01

    affective neuroscience aimed at deepening the understanding of embodied felt sense. The Rx6 approach is based in aesthetics, a pragmatic pre-understanding inspired from an interpretive and a constructivist tradition, and it is a heuristic endeavour where art is applied towards the creation of meaning......Using Aesthetic Response, a Poetic Inquiry to Expand Knowing Abstract: The Rx6-Method A simple step-wise research procedure of arts-based research (ABR) called the Rx6 method is presented. This ABR method is grounded in expressive arts therapy, heuristic inquiry, attachment theory and contemporary...

  7. Physical-chemical and operational performance of an anaerobic baffled reactor (ABR treating swine wastewater - 10.4025/actascitechnol.v32i4.7203

    Directory of Open Access Journals (Sweden)

    Erlon Lopes Pereira

    2010-12-01

    Full Text Available Since hog raising concentrates a huge amount of swine manure in small areas, it is considered by the environmental government organizations to be one of the most potentially pollutant activities. Therefore the main objective of this research was to evaluate by operational criteria and removal efficiency, the performance of a Anaerobic Baffled Reactor (ABR, working as a biological pre-treatment of swine culture effluents. The physical-chemical analyses carried out were: total COD, BOD5, total solids (TS, fix (TFS and volatiles (TVS, temperature, pH, total Kjeldahl nitrogen, phosphorus, total acidity and alkalinity. The ABR unit worked with an average efficiency of 65.2 and 76.2%, respectively, concerning total COD and BOD5, with a hydraulic retention time (HRT about 15 hours. The results for volumetric organic loading rate (VOLR, organic loading rate (OLR and hydraulic loading rate (HLR were: 4.46 kg BOD m-3 day-1; 1.81 kg BOD5 kg TVS-1 day-1 and 1.57 m3 m-3 day-1, respectively. The average efficiency of the whole treatment system for total COD and BOD5 removal were 66.5 and 77.8%, showing an adequate performance in removing the organic matter from swine wastewater.

  8. Key Brainstem Structures Activated during Hypoxic Exposure in One-day-old Mice Highlight Characteristics for Modeling Breathing Network in Premature Infants

    Science.gov (United States)

    Joubert, Fanny; Loiseau, Camille; Perrin-Terrin, Anne-Sophie; Cayetanot, Florence; Frugière, Alain; Voituron, Nicolas; Bodineau, Laurence

    2016-01-01

    We mapped and characterized changes in the activity of brainstem cell groups under hypoxia in one-day-old newborn mice, an animal model in which the central nervous system at birth is particularly immature. The classical biphasic respiratory response characterized by transient hyperventilation, followed by severe ventilation decline, was associated with increased c-FOS immunoreactivity in brainstem cell groups: the nucleus of the solitary tract, ventral reticular nucleus of the medulla, retrotrapezoid/parafacial region, parapyramidal group, raphe magnus nucleus, lateral, and medial parabrachial nucleus, and dorsal subcoeruleus nucleus. In contrast, the hypoglossal nucleus displayed decreased c-FOS immunoreactivity. There were fewer or no activated catecholaminergic cells activated in the medulla oblongata, whereas ~45% of the c-FOS-positive cells in the dorsal subcoeruleus were co-labeled. Approximately 30% of the c-FOS-positive cells in the parapyramidal group were serotoninergic, whereas only a small portion were labeled for serotonin in the raphe magnus nucleus. None of the c-FOS-positive cells in the retrotrapezoid/parafacial region were co-labeled for PHOX2B. Thus, the hypoxia-activated brainstem neuronal network of one-day-old mice is characterized by (i) the activation of catecholaminergic cells of the dorsal subcoeruleus nucleus, a structure implicated in the strong depressive pontine influence previously reported in the fetus but not in newborns, (ii) the weak activation of catecholaminergic cells of the ventral reticular nucleus of the medulla, an area involved in hypoxic hyperventilation, and (iii) the absence of PHOX2B-positive cells activated in the retrotrapezoid/parafacial region. Based on these results, one-day-old mice could highlight characteristics for modeling the breathing network of premature infants. PMID:28018238

  9. Key brainstem structures activated during hypoxic exposure in one-day-old mice highlight characteristics for modelling breathing network in premature infants

    Directory of Open Access Journals (Sweden)

    Fanny JOUBERT

    2016-12-01

    Full Text Available We mapped and characterized changes in the activity of brainstem cell groups under hypoxia in one-day-old newborn mice, an animal model in which the central nervous system at birth is particularly immature. The classical biphasic respiratory response characterized by transient hyperventilation, followed by severe ventilation decline, was associated with increased c-FOS immunoreactivity in brainstem cell groups: the nucleus of the solitary tract, ventral reticular nucleus of the medulla, retrotrapezoid/parafacial region, parapyramidal group, raphe magnus nucleus, lateral and medial parabrachial nucleus, and dorsal subcoeruleus nucleus. In contrast, the hypoglossal nucleus displayed decreased c-FOS immunoreactivity. There were fewer or no activated catecholaminergic cells activated in the medulla oblongata, whereas approximately 45% of the c-FOS-positive cells in the dorsal subcoeruleus were co-labelled. Approximately 30% of the c-FOS-positive cells in the parapyramidal group were serotoninergic, whereas only a small portion were labelled for serotonin in the raphe magnus nucleus. None of the c-FOS-positive cells in the retrotrapezoid/parafacial region were co-labelled for PHOX2B. Thus, the hypoxia-activated brainstem neuronal network of one-day-old mice is characterized by i the activation of catecholaminergic cells of the dorsal subcoeruleus nucleus, a structure implicated in the strong depressive pontine influence previously reported in the fetus but not in newborns, ii the weak activation of catecholaminergic cells of the ventral reticular nucleus of the medulla, an area involved in hypoxic hyperventilation, and iii the absence of PHOX2B-positive cells activated in the retrotrapezoid/parafacial region. Based on these results, one-day-old mice could highlight characteristics for modelling the breathing network of premature infants.

  10. Optimal technique of linear accelerator–based stereotactic radiosurgery for tumors adjacent to brainstem

    International Nuclear Information System (INIS)

    Chang, Chiou-Shiung; Hwang, Jing-Min; Tai, Po-An; Chang, You-Kang; Wang, Yu-Nong; Shih, Rompin; Chuang, Keh-Shih

    2016-01-01

    Stereotactic radiosurgery (SRS) is a well-established technique that is replacing whole-brain irradiation in the treatment of intracranial lesions, which leads to better preservation of brain functions, and therefore a better quality of life for the patient. There are several available forms of linear accelerator (LINAC)–based SRS, and the goal of the present study is to identify which of these techniques is best (as evaluated by dosimetric outcomes statistically) when the target is located adjacent to brainstem. We collected the records of 17 patients with lesions close to the brainstem who had previously been treated with single-fraction radiosurgery. In all, 5 different lesion catalogs were collected, and the patients were divided into 2 distance groups—1 consisting of 7 patients with a target-to-brainstem distance of less than 0.5 cm, and the other of 10 patients with a target-to-brainstem distance of ≥ 0.5 and < 1 cm. Comparison was then made among the following 3 types of LINAC-based radiosurgery: dynamic conformal arcs (DCA), intensity-modulated radiosurgery (IMRS), and volumetric modulated arc radiotherapy (VMAT). All techniques included multiple noncoplanar beams or arcs with or without intensity-modulated delivery. The volume of gross tumor volume (GTV) ranged from 0.2 cm 3 to 21.9 cm 3 . Regarding the dose homogeneity index (HI ICRU ) and conformity index (CI ICRU ) were without significant difference between techniques statistically. However, the average CI ICRU = 1.09 ± 0.56 achieved by VMAT was the best of the 3 techniques. Moreover, notable improvement in gradient index (GI) was observed when VMAT was used (0.74 ± 0.13), and this result was significantly better than those achieved by the 2 other techniques (p < 0.05). For V 4 Gy of brainstem, both VMAT (2.5%) and IMRS (2.7%) were significantly lower than DCA (4.9%), both at the p < 0.05 level. Regarding V 2 Gy of normal brain, VMAT plans had attained 6.4 ± 5%; this was significantly better

  11. ABA signaling in stress-response and seed development.

    Science.gov (United States)

    Nakashima, Kazuo; Yamaguchi-Shinozaki, Kazuko

    2013-07-01

    KEY MESSAGE : We review the recent progress on ABA signaling, especially ABA signaling for ABA-dependent gene expression, including the AREB/ABF regulon, SnRK2 protein kinase, 2C-type protein phosphatases and ABA receptors. Drought negatively impacts plant growth and the productivity of crops. Drought causes osmotic stress to organisms, and the osmotic stress causes dehydration in plant cells. Abscisic acid (ABA) is produced under osmotic stress conditions, and it plays an important role in the stress response and tolerance of plants. ABA regulates many genes under osmotic stress conditions. It also regulates gene expression during seed development and germination. The ABA-responsive element (ABRE) is the major cis-element for ABA-responsive gene expression. ABRE-binding protein (AREB)/ABRE-binding factor (ABF) transcription factors (TFs) regulate ABRE-dependent gene expression. Other TFs are also involved in ABA-responsive gene expression. SNF1-related protein kinases 2 are the key regulators of ABA signaling including the AREB/ABF regulon. Recently, ABA receptors and group A 2C-type protein phosphatases were shown to govern the ABA signaling pathway. Moreover, recent studies have suggested that there are interactions between the major ABA signaling pathway and other signaling factors in stress-response and seed development. The control of the expression of ABA signaling factors may improve tolerance to environmental stresses.

  12. Transcriptional regulation of ABI3- and ABA-responsive genes including RD29B and RD29A in seeds, germinating embryos, and seedlings of Arabidopsis.

    Science.gov (United States)

    Nakashima, Kazuo; Fujita, Yasunari; Katsura, Koji; Maruyama, Kyonoshin; Narusaka, Yoshihiro; Seki, Motoaki; Shinozaki, Kazuo; Yamaguchi-Shinozaki, Kazuko

    2006-01-01

    ABA-responsive elements (ABREs) are cis-acting elements and basic leucine zipper (bZIP)-type ABRE-binding proteins (AREBs) are transcriptional activators that function in the expression of RD29B in vegetative tissue of Arabidopsis in response to abscisic acid (ABA) treatment. Dehydration-responsive elements (DREs) function as coupling elements of ABRE in the expression of RD29A in response to ABA. Expression analysis using abi3 and abi5 mutants showed that ABI3 and ABI5 play important roles in the expression of RD29B in seeds. Base-substitution analysis showed that two ABREs function strongly and one ABRE coupled with DRE functions weakly in the expression of RD29A in embryos. In a transient transactivation experiment, ABI3, ABI5 and AREB1 activated transcription of a GUS reporter gene driven by the RD29B promoter strongly but these proteins activated the transcription driven by the RD29A promoter weakly. In 35S::ABI3 Arabidopsis plants, the expression of RD29B was up-regulated strongly, but that of RD29A was up-regulated weakly. These results indicate that the expression of RD29B having ABREs in the promoter is up-regulated strongly by ABI3, whereas that of RD29A having one ABRE coupled with DREs in the promoter is up-regulated weakly by ABI3. We compared the expression of 7000 Arabidopsis genes in response to ABA treatment during germination and in the vegetative growth stage, and that in 35S::ABI3 plants using a full-length cDNA microarray. The expression of ABI3- and/or ABA-responsive genes and cis-elements in the promoters are discussed.

  13. Neurodegenerative changes in the brainstem and olfactory bulb in people older than 50 years old: a descriptive study

    Directory of Open Access Journals (Sweden)

    Francine Hehn de Oliveira

    2015-07-01

    Full Text Available With the increase in life expectancy in Brazil, concerns have grown about the most prevalent diseases in elderly people. Among these diseases are neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases. Protein deposits related to the development of these diseases can pre-date the symptomatic phases by years. The tau protein is particularly interesting: it might be found in the brainstem and olfactory bulb long before it reaches the limbic cortex, at which point symptoms occur. Of the 14 brains collected in this study, the tau protein was found in the brainstems of 10 (71.42% and in olfactory bulbs of 3 out 11. Of the 7 individuals who had a final diagnosis of Alzheimer’s disease (AD, 6 presented tau deposits in some region of the brainstem. Our data support the idea of the presence of tau protein in the brainstem and olfactory bulb in the earliest stages of AD.

  14. 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.)

  15. Sequential change in MRI in two cases with small brainstem infarctions

    International Nuclear Information System (INIS)

    Masuda, Ryoichi; Fukuda, Osamu; Endoh, Shunro; Takaku, Akira; Suzuki, Takashi; Satoh, Shuji

    1987-01-01

    Magnetic resonance imaging (MRI) has been found to be very useful for the diagnosis of a small brainstem infarction. However, most reported cases have shown the changes at only the chronic stage. In this report, sequential changes in the MRI in two cases with small brainstem infarctions are presented. In Case 1, a 67-year-old man with a pure sensory stroke on the right side, a small infarcted area was observed at the left medial side of the pontomedullary junction on MRI. In Case 2, a 62-year-old man with a pure motor hemiparesis of the left side, MRI revealed a small infarcted area on the right ventral of the middle pons. The initial changes were confirmed 5 days (Case 1) and 18 hours (Case 2) after the onset of the completed stroke. No abnormal findings could be found in the computed tomography in either case. (author)

  16. Hypertensive brainstem encephalopathy involving deep supratentorial regions: does only blood pressure matter?

    Directory of Open Access Journals (Sweden)

    Jong-Ho Park

    2010-04-01

    Full Text Available We report on a 42-year-old female patient who presented with high arterial blood pressure of 245/150 mmHg and hypertensive brainstem encephalopathy that involved the brainstem and extensive supratentorial deep gray and white matter. The lesions were nearly completely resolved several days after stabilization of the arterial blood pressure. Normal diffusion-weighted imaging findings and high apparent diffusion coefficient values suggested that the main pathomechanism was vasogenic edema owing to severe hypertension. On the basis of a literature review, the absolute value of blood pressure or whether the patient can control his/her blood pressure seems not to be associated with the degree of the lesions evident on magnetic resonance imaging. It remains to be determined if the acceleration rate and the duration of elevated arterial blood pressure might play a key role in the development of the hypertensive encephalopathy pattern.

  17. Multi-sensory integration in brainstem and auditory cortex.

    Science.gov (United States)

    Basura, Gregory J; Koehler, Seth D; Shore, Susan E

    2012-11-16

    Tinnitus is the perception of sound in the absence of a physical sound stimulus. It is thought to arise from aberrant neural activity within central auditory pathways that may be influenced by multiple brain centers, including the somatosensory system. Auditory-somatosensory (bimodal) integration occurs in the dorsal cochlear nucleus (DCN), where electrical activation of somatosensory regions alters pyramidal cell spike timing and rates of sound stimuli. Moreover, in conditions of tinnitus, bimodal integration in DCN is enhanced, producing greater spontaneous and sound-driven neural activity, which are neural correlates of tinnitus. In primary auditory cortex (A1), a similar auditory-somatosensory integration has been described in the normal system (Lakatos et al., 2007), where sub-threshold multisensory modulation may be a direct reflection of subcortical multisensory responses (Tyll et al., 2011). The present work utilized simultaneous recordings from both DCN and A1 to directly compare bimodal integration across these separate brain stations of the intact auditory pathway. Four-shank, 32-channel electrodes were placed in DCN and A1 to simultaneously record tone-evoked unit activity in the presence and absence of spinal trigeminal nucleus (Sp5) electrical activation. Bimodal stimulation led to long-lasting facilitation or suppression of single and multi-unit responses to subsequent sound in both DCN and A1. Immediate (bimodal response) and long-lasting (bimodal plasticity) effects of Sp5-tone stimulation were facilitation or suppression of tone-evoked firing rates in DCN and A1 at all Sp5-tone pairing intervals (10, 20, and 40 ms), and greater suppression at 20 ms pairing-intervals for single unit responses. Understanding the complex relationships between DCN and A1 bimodal processing in the normal animal provides the basis for studying its disruption in hearing loss and tinnitus models. This article is part of a Special Issue entitled: Tinnitus Neuroscience

  18. Modeling Parkinson’s Disease Falls Associated With Brainstem Cholinergic Systems Decline

    OpenAIRE

    Kucinski, Aaron; Sarter, Martin

    2015-01-01

    In addition to the primary disease-defining symptoms, approximately half of patients with Parkinson’s disease (PD) suffer from postural instability, impairments in gait control and a propensity for falls. Consistent with evidence from patients, we previously demonstrated that combined striatal dopamine (DA) and basal forebrain (BF) cholinergic cell loss causes falls in rats traversing dynamic surfaces. Because evidence suggests that degeneration of brainstem cholinergic neurons arising from t...

  19. Neurochemical dynamics of acute orofacial pain in the human trigeminal brainstem nuclear complex.

    Science.gov (United States)

    de Matos, Nuno M P; Hock, Andreas; Wyss, Michael; Ettlin, Dominik A; Brügger, Mike

    2017-11-15

    The trigeminal brainstem sensory nuclear complex is the first central relay structure mediating orofacial somatosensory and nociceptive perception. Animal studies suggest a substantial involvement of neurochemical alterations at such basal CNS levels in acute and chronic pain processing. Translating this animal based knowledge to humans is challenging. Human related examining of brainstem functions are challenged by MR related peculiarities as well as applicability aspects of experimentally standardized paradigms. Based on our experience with an MR compatible human orofacial pain model, the aims of the present study were twofold: 1) from a technical perspective, the evaluation of proton magnetic resonance spectroscopy at 3 T regarding measurement accuracy of neurochemical profiles in this small brainstem nuclear complex and 2) the examination of possible neurochemical alterations induced by an experimental orofacial pain model. Data from 13 healthy volunteers aged 19-46 years were analyzed and revealed high quality spectra with significant reductions in total N-acetylaspartate (N-acetylaspartate + N-acetylaspartylglutamate) (-3.7%, p = 0.009) and GABA (-10.88%, p = 0.041) during the pain condition. These results might reflect contributions of N-acetylaspartate and N-acetylaspartylglutamate in neuronal activity-dependent physiologic processes and/or excitatory neurotransmission, whereas changes in GABA might indicate towards a reduction in tonic GABAergic functioning during nociceptive signaling. Summarized, the present study indicates the applicability of 1 H-MRS to obtain neurochemical dynamics within the human trigeminal brainstem sensory nuclear complex. Further developments are needed to pave the way towards bridging important animal based knowledge with human research to understand the neurochemistry of orofacial nociception and pain. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Limbic encephalitis with antibodies to glutamic acid decarboxylase presenting with brainstem symptoms

    Directory of Open Access Journals (Sweden)

    Faruk Incecik

    2015-01-01

    Full Text Available Limbic encephalitis (LE is a neurological syndrome that may present in association with cancer, infection, or as an isolate clinical condition often accompanying autoimmune disorders. LE associated with glutamic acid decarboxylase antibodies (anti-GAD is rare in children. Here, we characterized the clinical and laboratory features of a patient presenting with brainstem involvement with non-paraneoplastic LE associated with anti-GAD antibodies. In our patient, after plasma exchange, we determined a dramatic improvement of the neurological deficits.

  1. Somatotopic Arrangement and Location of the Corticospinal Tract in the Brainstem of the Human Brain

    OpenAIRE

    Jang, Sung Ho

    2011-01-01

    The corticospinal tract (CST) is the most important motor pathway in the human brain. Detailed knowledge of CST somatotopy is important in terms of rehabilitative management and invasive procedures for patients with brain injuries. In this study, I conducted a review of nine previous studies of the somatotopical location and arrangement at the brainstem in the human brain. The results of this review indicated that the hand and leg somatotopies of the CST are arranged medio-laterally in the mi...

  2. Retrospective analysis of 104 histologically proven adult brainstem gliomas: clinical symptoms, therapeutic approaches and prognostic factors

    International Nuclear Information System (INIS)

    Reithmeier, Thomas; Kuzeawu, Aanyo; Hentschel, Bettina; Loeffler, Markus; Trippel, Michael; Nikkhah, Guido

    2014-01-01

    Adult brainstem gliomas are rare primary brain tumors (<2% of gliomas). The goal of this study was to analyze clinical, prognostic and therapeutic factors in a large series of histologically proven brainstem gliomas. Between 1997 and 2007, 104 patients with a histologically proven brainstem glioma were retrospectively analyzed. Data about clinical course of disease, neuropathological findings and therapeutic approaches were analyzed. The median age at diagnosis was 41 years (range 18-89 years), median KPS before any operative procedure was 80 (range 20-100) and median survival for the whole cohort was 18.8 months. Histopathological examinations revealed 16 grade I, 31 grade II, 42 grade III and 14 grade IV gliomas. Grading was not possible in 1 patient. Therapeutic concepts differed according to the histopathology of the disease. Median overall survival for grade II tumors was 26.4 months, for grade III tumors 12.9 months and for grade IV tumors 9.8 months. On multivariate analysis the relative risk to die increased with a KPS ≤ 70 by factor 6.7, with grade III/IV gliomas by the factor 1.8 and for age ≥ 40 by the factor 1.7. External beam radiation reduced the risk to die by factor 0.4. Adult brainstem gliomas present with a wide variety of neurological symptoms and postoperative radiation remains the cornerstone of therapy with no proven benefit of adding chemotherapy. Low KPS, age ≥ 40 and higher tumor grade have a negative impact on overall survival

  3. Organization of the auditory brainstem in a lizard, Gekko gecko. I. Auditory nerve, cochlear nuclei, and superior olivary nuclei

    DEFF Research Database (Denmark)

    Tang, Y. Z.; Christensen-Dalsgaard, J.; Carr, C. E.

    2012-01-01

    We used tract tracing to reveal the connections of the auditory brainstem in the Tokay gecko (Gekko gecko). The auditory nerve has two divisions, a rostroventrally directed projection of mid- to high best-frequency fibers to the nucleus angularis (NA) and a more dorsal and caudal projection of lo...... of auditory connections in lizards and archosaurs but also different processing of low- and high-frequency information in the brainstem. J. Comp. Neurol. 520:17841799, 2012. (C) 2011 Wiley Periodicals, Inc...

  4. Category-specific visual responses: an intracranial study comparing gamma, beta, alpha and ERP response selectivity

    Directory of Open Access Journals (Sweden)

    Juan R Vidal

    2010-11-01

    Full Text Available The specificity of neural responses to visual objects is a major topic in visual neuroscience. In humans, functional magnetic resonance imaging (fMRI studies have identified several regions of the occipital and temporal lobe that appear specific to faces, letter-strings, scenes, or tools. Direct electrophysiological recordings in the visual cortical areas of epileptic patients have largely confirmed this modular organization, using either single-neuron peri-stimulus time-histogram or intracerebral event-related potentials (iERP. In parallel, a new research stream has emerged using high-frequency gamma-band activity (50-150 Hz (GBR and low-frequency alpha/beta activity (8-24 Hz (ABR to map functional networks in humans. An obvious question is now whether the functional organization of the visual cortex revealed by fMRI, ERP, GBR, and ABR coincide. We used direct intracerebral recordings in 18 epileptic patients to directly compare GBR, ABR, and ERP elicited by the presentation of seven major visual object categories (faces, scenes, houses, consonants, pseudowords, tools, and animals, in relation to previous fMRI studies. Remarkably both GBR and iERP showed strong category-specificity that was in many cases sufficient to infer stimulus object category from the neural response at single-trial level. However, we also found a strong discrepancy between the selectivity of GBR, ABR, and ERP with less than 10% of spatial overlap between sites eliciting the same category-specificity. Overall, we found that selective neural responses to visual objects were broadly distributed in the brain with a prominent spatial cluster located in the posterior temporal cortex. Moreover, the different neural markers (GBR, ABR, and iERP that elicit selectivity towards specific visual object categories present little spatial overlap suggesting that the information content of each marker can uniquely characterize high-level visual information in the brain.

  5. Awake craniotomy for assisting placement of auditory brainstem implant in NF2 patients.

    Science.gov (United States)

    Zhou, Qiangyi; Yang, Zhijun; Wang, Zhenmin; Wang, Bo; Wang, Xingchao; Zhao, Chi; Zhang, Shun; Wu, Tao; Li, Peng; Li, Shiwei; Zhao, Fu; Liu, Pinan

    2018-06-01

    Auditory brainstem implants (ABIs) may be the only opportunity for patients with NF2 to regain some sense of hearing sensation. However, only a very small number of individuals achieved open-set speech understanding and high sentence scores. Suboptimal placement of the ABI electrode array over the cochlear nucleus may be one of main factors for poor auditory performance. In the current study, we present a method of awake craniotomy to assist with ABI placement. Awake surgery and hearing test via the retrosigmoid approach were performed for vestibular schwannoma resections and auditory brainstem implantations in four patients with NF2. Auditory outcomes and complications were assessed postoperatively. Three of 4 patients who underwent awake craniotomy during ABI surgery received reproducible auditory sensations intraoperatively. Satisfactory numbers of effective electrodes, threshold levels and distinct pitches were achieved in the wake-up hearing test. In addition, relatively few electrodes produced non-auditory percepts. There was no serious complication attributable to the ABI or awake craniotomy. It is safe and well tolerated for neurofibromatosis type 2 (NF2) patients using awake craniotomy during auditory brainstem implantation. This method can potentially improve the localization accuracy of the cochlear nucleus during surgery.

  6. Features of the brainstem and tentorial foramen relationship and their practical value

    Directory of Open Access Journals (Sweden)

    O. V. Redyakina

    2016-11-01

    Full Text Available Objective. Establish the morphological features and practical significance of the tentorial-stem relationship from the position of individual anatomical variability. Methods: head morphometry, macro and microscopic examination of the brainstem, morphometry of the brainstem and its departments, tentorial aperture morphometry, foramen magnum craniometry, manufacture of corrosion molds of the posterior cranial fossa, statistical processing of the results, computer-graphic modeling of the brainstem and surrounding formations. Results.  In the course of the study, the features of the individual variability of the tentorial foramen form were established, namely: shortened-expanded and oval-convex forms were defined in brachycephalic; in dolichocephalic - oblong-narrowed and elongated-conical. At the same time, a number of existing sizes and forms of the tentorial-stem spaces were noted. Among them, four main ones are described: front, side (right and left and rear. They have individual characteristics. Thus, in the brachycephalic we define lateral holes, due to the convexity of the tentorial margins. In dolichocephalic - front and back gaps, depending on the characteristics of their elongations. The obtained data are of great importance for the craniotopographic justification of the tentorial-stem wedges, which are formed with tumors which located here. In our opinion, tumors have the greatest possibility of passage through the left or right lateral intervals in people with a brachymorph form of the head, and through the anterior and posterior intervals - in people with meso- and dolichomorph forms of the head.

  7. Blast overpressure induced axonal injury changes in rat brainstem and spinal cord

    Directory of Open Access Journals (Sweden)

    Srinivasu Kallakuri

    2015-01-01

    Full Text Available Introduction: Blast induced neurotrauma has been the signature wound in returning soldiers from the ongoing wars in Iraq and Afghanistan. Of importance is understanding the pathomechansim(s of blast overpressure (OP induced axonal injury. Although several recent animal models of blast injury indicate the neuronal and axonal injury in various brain regions, animal studies related to axonal injury in the white matter (WM tracts of cervical spinal cord are limited. Objective: The purpose of this study was to assess the extent of axonal injury in WM tracts of cervical spinal cord in male Sprague Dawley rats subjected to a single insult of blast OP. Materials and Methods: Sagittal brainstem sections and horizontal cervical spinal cord sections from blast and sham animals were stained by neurofilament light (NF-L chain and beta amyloid precursor protein immunocytochemistry and observed for axonal injury changes. Results: Observations from this preliminary study demonstrate axonal injury changes in the form of prominent swellings, retraction bulbs, and putative signs of membrane disruptions in the brainstem and cervical spinal cord WM tracts of rats subjected to blast OP. Conclusions: Prominent axonal injury changes following the blast OP exposure in brainstem and cervical spinal WM tracts underscores the need for careful evaluation of blast induced injury changes and associated symptoms. NF-L immunocytochemistry can be considered as an additional tool to assess the blast OP induced axonal injury.

  8. Gamma Knife Radiosurgery Treatment for Metastatic Melanoma of the Trigeminal Nerve and Brainstem: A Case Report and a Review of the Literature

    Science.gov (United States)

    Peterson, Halloran E.; Larson, Erik W.; Fairbanks, Robert K.; Lamoreaux, Wayne T.; Mackay, Alexander R.; Call, Jason A.; Demakas, John J.; Cooke, Barton S.; Lee, Christopher M.

    2013-01-01

    Objective and Importance. Brainstem metastases (BSMs) are uncommon but serious complications of some cancers. They cause significant neurological deficit, and options for treatment are limited. Stereotactic radiosurgery (SRS) has been shown to be a safe and effective treatment for BSMs that prolongs survival and can preserve or in some cases improve neurological function. This case illustrates the use of repeated SRS, specifically Gamma Knife radiosurgery (GKRS) for management of a unique brainstem metastasis. Clinical Presentation. This patient presented 5 years after the removal of a lentigo maligna melanoma from her left cheek with left sided facial numbness and paresthesias with no reported facial weakness. Initial MRI revealed a mass on the left trigeminal nerve that appeared to be a trigeminal schwannoma. Intervention. After only limited response to the first GKRS treatment, a biopsy of the tumor revealed it to be metastatic melanoma, not schwannoma. Over the next two years, the patient would receive 3 more GKRS treatments. These procedures were effective in controlling growth in the treated areas, and the patient has maintained a good quality of life. Conclusion. GKRS has proven in this case to be effective in limiting the growth of this metastatic melanoma without acute adverse effects. PMID:24194991

  9. Mechanical Characterization of Immature Porcine Brainstem in Tension at Dynamic Strain Rates.

    Science.gov (United States)

    Zhao, Hui; Yin, Zhiyong; Li, Kui; Liao, Zhikang; Xiang, Hongyi; Zhu, Feng

    2016-01-21

    Many brain injury cases involve pediatric road traffic accidents, and among these, brainstem injury causes disastrous outcomes. A thorough understanding of the tensile characterization of immature brainstem tissue is crucial in modeling traumatic brain injury sustained by children, but limited experimental data in tension is available for the immature brain tissue at dynamic strain rates. We harvested brainstem tissue from immature pigs (about 4 weeks old, and at a developmental stage similar to that of human toddlers) as a byproduct from a local slaughter house and very carefully prepared the samples. Tensile tests were performed on specimens at dynamic strain rates of 2/s, 20/s, and 100/s using a biological material instrument. The constitutive models, Fung, Ogden, Gent, and exponential function, for immature brainstem tissue material property were developed for the recorded experimental data using OriginPro 8.0 software. The t test was performed for infinitesimal shear modules. The curves of stress-versus-stretch ratio were convex in shape, and inflection points were found in all the test groups at the strain of about 2.5%. The average Lagrange stress of the immature brainstem specimen at the 30% strain at the strain rates of 2, 20, and 100/s was 273±114, 515±107, and 1121±197 Pa, respectively. The adjusted R-Square (R2) of Fung, Ogden, Gent, and exponential model was 0.820≤R2≤0.933, 0.774≤R2≤0.940, 0.650≤R2≤0.922, and 0.852≤R2≤0.981, respectively. The infinitesimal shear modulus of the strain energy functions showed a significant association with the strain rate (pmaterial in dynamic tensile tests, and the tissue becomes stiffer with increased strain rate. The reported results may be useful in the study of brain injuries in children who sustain injuries in road traffic accidents. Further research in more detail should be performed in the future.

  10. Robust Machine Learning-Based Correction on Automatic Segmentation of the Cerebellum and Brainstem.

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    Jun Yi Wang

    Full Text Available Automated segmentation is a useful method for studying large brain structures such as the cerebellum and brainstem. However, automated segmentation may lead to inaccuracy and/or undesirable boundary. The goal of the present study was to investigate whether SegAdapter, a machine learning-based method, is useful for automatically correcting large segmentation errors and disagreement in anatomical definition. We further assessed the robustness of the method in handling size of training set, differences in head coil usage, and amount of brain atrophy. High resolution T1-weighted images were acquired from 30 healthy controls scanned with either an 8-channel or 32-channel head coil. Ten patients, who suffered from brain atrophy because of fragile X-associated tremor/ataxia syndrome, were scanned using the 32-channel head coil. The initial segmentations of the cerebellum and brainstem were generated automatically using Freesurfer. Subsequently, Freesurfer's segmentations were both manually corrected to serve as the gold standard and automatically corrected by SegAdapter. Using only 5 scans in the training set, spatial overlap with manual segmentation in Dice coefficient improved significantly from 0.956 (for Freesurfer segmentation to 0.978 (for SegAdapter-corrected segmentation for the cerebellum and from 0.821 to 0.954 for the brainstem. Reducing the training set size to 2 scans only decreased the Dice coefficient ≤0.002 for the cerebellum and ≤ 0.005 for the brainstem compared to the use of training set size of 5 scans in corrective learning. The method was also robust in handling differences between the training set and the test set in head coil usage and the amount of brain atrophy, which reduced spatial overlap only by <0.01. These results suggest that the combination of automated segmentation and corrective learning provides a valuable method for accurate and efficient segmentation of the cerebellum and brainstem, particularly in large

  11. Brainstem projections of neurons located in various subdivisions of the dorsolateral hypothalamic area – an anterograde tract-tracing study

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    Rege Sugárka Papp

    2014-05-01

    Full Text Available The projections from the dorsolateral hypothalamic area (DLH to the lower brainstem have been investigated by using biotinylated dextran amine (BDA, an anterograde tracer in rats. The DLH can be divided into 3 areas (dorsomedial hypothalamus, perifornical area, lateral hypothalamic area, and further subdivided into 8 subdivisions. After unilateral stereotaxic injections of BDA into individual DLH subdivisions, the correct sites of injections were controlled histologically, and the distribution patterns of BDA-positive fibers were mapped on serial sections between the hypothalamus and spinal cord in 22 rats. BDA-labeled fibers were observable over 100 different brainstem areas, nuclei or subdivisions. Injections into the 8 DLH subdivisions established distinct topographical patterns. In general, the density of labeled fibers was low in the lower brainstem. High density of fibers was seen only 4 of the 116 areas: in the lateral and ventrolateral parts of the periaqueductal gray, the Barrington’s and the pedunculopontine tegmental nuclei. All of the biogenic amine cell groups in the lower brainstem (9 noradrenaline, 3 adrenaline and 9 serotonin cell groups received labeled fibers, some of them from all, or at least 7 DLH subdivisions, mainly from perifornical and ventral lateral hypothalamic neurons. Some of the tegmental nuclei and nuclei of the reticular formation were widely innervated, although the density of the BDA-labeled fibers was generally low. No definitive descending BDA-positive pathway, but long-run solitaire BDA-labeled fibers were seen in the lower brainstem. These descending fibers joined some of the large tracts or fasciculi in the brainstem. The distribution pattern of BDA-positive fibers of DLH origin throughout the lower brainstem was comparable to patterns of previously published orexin- or melanin-concentrating hormone-immunoreactive fibers with somewhat differences.

  12. Brainstem auditory evoked responses in healthy Argentine Mastiff dogs recorded with surface electrodes

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    M. Armașu

    2015-10-01

    Full Text Available RESUMOEvocado auditivo de respostas – BAER foi gravado utilizando eletrodos de superfície em sete cães Mastiff argentino saudáveis para estimulações monoaural e binaural em intensidades sonoras de 90 dB NPS . As latências e amplitudes das ondas I, III e V bem como os intervalos InterWave I- III , III -V e IV foram calculados. As diferenças estatísticas foram obtidas para as ondas III e latências V, amplitudes das ondas III e intervalos I- III e I-V entre mono e estimulação binaural. Por serem uma das raças geneticamente predispostas à surdez congênita, obtendo valores de referência BAER, os cães Mastiff argentino têm uma importância clínica especial.

  13. Searching for the optimal stimulus eliciting auditory brainstem responses in humans

    DEFF Research Database (Denmark)

    Fobel, Oliver; Dau, Torsten

    2004-01-01

    -chirp, was based on estimates of human basilar membrane (BM) group delays derived from stimulus-frequency otoacoustic emissions (SFOAE) at a sound pressure level of 40 dB [Shera and Guinan, in Recent Developments in Auditory Mechanics (2000)]. The other chirp, referred to as the A-chirp, was derived from latency...

  14. TEN DAY EXPOSURES TO CARBONYL SULFIDE PRODUCE BRAINSTEM LESIONS AND CHANGES IN BRAINSTEM AUDITORY EVOKED RESPONSES IN FISCHER 344N RATS.

    Science.gov (United States)

    Carbonyl sulfide (COS) is a chemical intermediate in the production of pesticides and herbicides, a metabolite of carbon disulfide, a byproduct of the combustion of organic material, and a naturally occurring compound. COS was included in a Toxic Substances Control Act request fo...

  15. Acute and chronic craniofacial pain: brainstem mechanisms of nociceptive transmission and neuroplasticity, and their clinical correlates.

    Science.gov (United States)

    Sessle, B J

    2000-01-01

    This paper reviews the recent advances in knowledge of brainstem mechanisms related to craniofacial pain. It also draws attention to their clinical implications, and concludes with a brief overview and suggestions for future research directions. It first describes the general organizational features of the trigeminal brainstem sensory nuclear complex (VBSNC), including its input and output properties and intrinsic characteristics that are commensurate with its strategic role as the major brainstem relay of many types of somatosensory information derived from the face and mouth. The VBSNC plays a crucial role in craniofacial nociceptive transmission, as evidenced by clinical, behavioral, morphological, and electrophysiological data that have been especially derived from studies of the relay of cutaneous nociceptive afferent inputs through the subnucleus caudalis of the VBSNC. The recent literature, however, indicates that some fundamental differences exist in the processing of cutaneous vs. other craniofacial nociceptive inputs to the VBSNC, and that rostral components of the VBSNC may also play important roles in some of these processes. Modulatory mechanisms are also highlighted, including the neurochemical substrate by which nociceptive transmission in the VBSNC can be modulated. In addition, the long-term consequences of peripheral injury and inflammation and, in particular, the neuroplastic changes that can be induced in the VBSNC are emphasized in view of the likely role that central sensitization, as well as peripheral sensitization, can play in acute and chronic pain. The recent findings also provide new insights into craniofacial pain behavior and are particularly relevant to many approaches currently in use for the management of pain and to the development of new diagnostic and therapeutic procedures aimed at manipulating peripheral inputs and central processes underlying nociceptive transmission and its control within the VBSNC.

  16. Erythropoietin and its receptors in the brainstem of adults with fatal falciparum malaria

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    White Nicholas J

    2009-11-01

    Full Text Available Abstract Background Facilitation of endogenous neuroprotective pathways, such as the erythropoietin (Epo pathway, has been proposed as adjuvant treatment strategies in cerebral malaria. Whether different endogenous protein expression levels of Epo or differences in the abundance of its receptor components could account for the extent of structural neuropathological changes or neurological complications in adults with severe malaria was investigated. Methods High sensitivity immunohistochemistry was used to assess the frequency, distribution and concordance of Epo and components of its homodimeric and heteromeric receptors, Epo receptor and CD131, within the brainstem of adults who died of severe malaria. The following relationships with Epo and its receptor components were also defined: (i sequestration and indicators of hypoxia; (ii vascular damage in the form of plasma protein leakage and haemorrhage; (iii clinical complications and neuropathological features of severe malaria disease. Brainstems of patients dying in the UK from unrelated non-infectious causes were examined for comparison. Results The incidence of endogenous Epo in parenchymal brain cells did not greatly differ between severe malaria and non-neurological UK controls at the time of death. However, EpoR and CD131 labelling of neurons was greater in severe malaria compared with non-neurological controls (P = .009. EpoR labelling of vessels was positively correlated with admission peripheral parasite count (P = .01 and cerebral sequestration (P P = .001. There were no significant correlations with indicators of vascular damage, neuronal chromatolysis, axonal swelling or vital organ failure. Conclusion Cells within the brainstem of severe malaria patients showed protein expression of Epo and its receptor components. However, the incidence of endogeneous expression did not reflect protection from vascular or neuronal injury, and/or clinical manifestations, such as coma. These

  17. Enterovirus 71 can directly infect the brainstem via cranial nerves and infection can be ameliorated by passive immunization.

    Science.gov (United States)

    Tan, Soon Hao; Ong, Kien Chai; Wong, Kum Thong

    2014-11-01

    Enterovirus 71 (EV71)-associated hand, foot, and mouth disease may be complicated by encephalomyelitis. We investigated EV71 brainstem infection and whether this infection could be ameliorated by passive immunization in a mouse model. Enterovirus 71 was injected into unilateral jaw/facial muscles of 2-week-old mice, and hyperimmune sera were given before or after infection. Harvested tissues were studied by light microscopy, immunohistochemistry, in situ hybridization, and viral titration. In unimmunized mice, viral antigen and RNA were detected within 24 hours after infection only in ipsilateral cranial nerves, motor trigeminal nucleus, reticular formation, and facial nucleus; viral titers were significantly higher in the brainstem than in the spinal cord samples. Mice given preinfection hyperimmune serum showed a marked reduction of ipsilateral viral antigen/RNA and viral titers in the brainstem in a dose-dependent manner. With optimum hyperimmune serum given after infection, brainstem infection was significantly reduced in a time-dependent manner. A delay in disease onset and a reduction of disease severity and mortality were also observed. Thus, EV71 can directly infect the brainstem, including the medulla, via cranial nerves, most likely by retrograde axonal transport. This may explain the sudden cardiorespiratory collapse in human patients with fatal encephalomyelitis. Moreover, our results suggest that passive immunization may still benefit EV71-infected patients who have neurologic complications.

  18. Individual differences in brainstem and basal ganglia structure predict postural control and balance loss in young and older adults.

    Science.gov (United States)

    Boisgontier, Matthieu P; Cheval, Boris; Chalavi, Sima; van Ruitenbeek, Peter; Leunissen, Inge; Levin, Oron; Nieuwboer, Alice; Swinnen, Stephan P

    2017-02-01

    It remains unclear which specific brain regions are the most critical for human postural control and balance, and whether they mediate the effect of age. Here, associations between postural performance and corticosubcortical brain regions were examined in young and older adults using multiple structural imaging and linear mixed models. Results showed that of the regions involved in posture, the brainstem was the strongest predictor of postural control and balance: lower brainstem volume predicted larger center of pressure deviation and higher odds of balance loss. Analyses of white and gray matter in the brainstem showed that the pedunculopontine nucleus area appeared to be critical for postural control in both young and older adults. In addition, the brainstem mediated the effect of age on postural control, underscoring the brainstem's fundamental role in aging. Conversely, lower basal ganglia volume predicted better postural performance, suggesting an association between greater neural resources in the basal ganglia and greater movement vigor, resulting in exaggerated postural adjustments. Finally, results showed that practice, shorter height and heavier weight (i.e., higher body mass index), higher total physical activity, and larger ankle active (but not passive) range of motion were predictive of more stable posture, irrespective of age. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Visual cortical somatosensory and brainstem auditory evoked potentials following incidental irradiation of the rhombencephalon

    International Nuclear Information System (INIS)

    Nightingale, S.; Schofield, I.S.; Dawes, P.J.D.K.

    1984-01-01

    Visual, cortical somatosensory and brainstem auditory evoked potentials were recorded before incidental irradiation of the rhombencephalon during radiotherapy in and around the middle ear, and at 11 weeks and eight months after completion of treatment. No patient experienced neurological symptoms during this period. No consistent changes in evoked potentials were found. The failure to demonstrate subclinical radiation-induced demyelination suggests either that the syndrome of early-delayed radiation rhombencephalopathy occurs in an idiosyncratic manner, or that any subclinical lesions are not detectable by serial evoked potential recordings. (author)

  20. Exploding Head Syndrome as Aura of Migraine with Brainstem Aura: A Case Report.

    Science.gov (United States)

    Rossi, Fabian H; Gonzalez, Elizabeth; Rossi, Elisa Marie; Tsakadze, Nina

    2018-01-01

    This article reports a case of exploding head syndrome (EHS) as an aura of migraine with brainstem aura (MBA). A middle-aged man presented with intermittent episodes of a brief sensation of explosion in the head, visual flashing, vertigo, hearing loss, tinnitus, confusion, ataxia, dysarthria, and bilateral visual impairment followed by migraine headache. The condition was diagnosed as MBA. Explosive head sensation, sensory phenomena, and headaches improved over time with nortriptyline. This case shows that EHS can present as a primary aura symptom in patients with MBA.

  1. Increased brainstem perfusion, but no blood-brain barrier disruption, during attacks of migraine with aura.

    Science.gov (United States)

    Hougaard, Anders; Amin, Faisal M; Christensen, Casper E; Younis, Samaira; Wolfram, Frauke; Cramer, Stig P; Larsson, Henrik B W; Ashina, Messoud

    2017-06-01

    See Moskowitz (doi:10.1093/brain/awx099) for a scientific commentary on this article.The migraine aura is characterized by transient focal cortical disturbances causing dramatic neurological symptoms that are usually followed by migraine headache. It is currently not understood how the aura symptoms are related to the headache phase of migraine. Animal studies suggest that cortical spreading depression, the likely mechanism of migraine aura, causes disruption of the blood-brain barrier and noxious stimulation of trigeminal afferents leading to activation of brainstem nuclei and triggering of migraine headache. We used the sensitive and validated technique of dynamic contrast-enhanced high-field magnetic resonance imaging to simultaneously investigate blood-brain barrier permeability and tissue perfusion in the brainstem (at the level of the lower pons), visual cortex, and brain areas of the anterior, middle and posterior circulation during spontaneous attacks of migraine with aura. Patients reported to our institution to undergo magnetic resonance imaging during the headache phase after presenting with typical visual aura. Nineteen patients were scanned during attacks and on an attack-free day. The mean time from attack onset to scanning was 7.6 h. We found increased brainstem perfusion bilaterally during migraine with aura attacks. Perfusion also increased in the visual cortex and posterior white matter following migraine aura. We found no increase in blood-brain barrier permeability in any of the investigated regions. There was no correlation between blood-brain barrier permeability, brain perfusion, and time from symptom onset to examination or pain intensity. Our findings demonstrate hyperperfusion in brainstem during the headache phase of migraine with aura, while the blood-brain barrier remains intact during attacks of migraine with aura. These data thus contradict the preclinical hypothesis of cortical spreading depression-induced blood-brain barrier

  2. A rare case of acute poster ior reversible encephalopathy syndrome involving brainstem in a child

    Directory of Open Access Journals (Sweden)

    Olfa Chakroun-Walha

    2016-11-01

    Full Text Available Posterior reversible encephalopathy syndrome (PRES is a rare entity involving brainstem in very rare reported cases. We describe here the case of a boy who presented to the emergency department for headaches and strabismus. Diagnosis of PRES was retained by magnetic resonance imaging. The causes were blood pressure urgency and renal failure. Location of lesions was very rarely reported in literature and neurological troubles were persistent. Emergency physicians should evocate PRES each time there is a clinical context associated with neurological troubles by a normal brain CT scan. Early diagnosis is very important to treat its causes and improve prognosis.

  3. Visual cortical somatosensory and brainstem auditory evoked potentials following incidental irradiation of the rhombencephalon

    Energy Technology Data Exchange (ETDEWEB)

    Nightingale, S. (Royal Victoria Infirmary, Newcastle upon Tyne (UK)); Schofield, I.S.; Dawes, P.J.D.K. (Newcastle upon Tyne Univ. (UK). Newcastle General Hospital)

    1984-01-01

    Visual, cortical somatosensory and brainstem auditory evoked potentials were recorded before incidental irradiation of the rhombencephalon during radiotherapy in and around the middle ear, and at 11 weeks and eight months after completion of treatment. No patient experienced neurological symptoms during this period. No consistent changes in evoked potentials were found. The failure to demonstrate subclinical radiation-induced demyelination suggests either that the syndrome of early-delayed radiation rhombencephalopathy occurs in an idiosyncratic manner, or that any subclinical lesions are not detectable by serial evoked potential recordings.

  4. 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. © 2017 Wiley Periodicals, Inc.

  5. Novel Anterior Brainstem Magnetic Resonance Imaging Findings in Non-Small Cell Lung Cancer with Leptomeningeal Carcinomatosis

    Directory of Open Access Journals (Sweden)

    Chun-Yu Cheng

    2017-10-01

    Full Text Available Leptomeningeal carcinomatosis (LC is found in around 4% of patients with non-small cell lung cancer (NSCLC. The most common radiological finding of LC is diffuse leptomeningeal enhancement on contrast-enhanced brain magnetic resonance imaging (MRI. Herein, we report a novel brain MRI finding—non-enhanced, band-like, symmetric restricted diffusion along the anterior surface of the brainstem—of LC in four patients with NSCLC. We also identified three additional cases with similar MRI findings in a literature review. We hypothesized that the restricted diffusion along the anterior brainstem was caused by malignant cells concentrating in the cistern around the brainstem and infiltrating into the circumferential perforating arteries along the anterior brainstem surface, which then resulted in microinfarctions.

  6. Activation of Brainstem Pro-opiomelanocortin Neurons Produces Opioidergic Analgesia, Bradycardia and Bradypnoea.

    Science.gov (United States)

    Cerritelli, Serena; Hirschberg, Stefan; Hill, Rob; Balthasar, Nina; Pickering, Anthony E

    2016-01-01

    Opioids are widely used medicinally as analgesics and abused for hedonic effects, actions that are each complicated by substantial risks such as cardiorespiratory depression. These drugs mimic peptides such as β-endorphin, which has a key role in endogenous analgesia. The β-endorphin in the central nervous system originates from pro-opiomelanocortin (POMC) neurons in the arcuate nucleus and nucleus of the solitary tract (NTS). Relatively little is known about the NTSPOMC neurons but their position within the sensory nucleus of the vagus led us to test the hypothesis that they play a role in modulation of cardiorespiratory and nociceptive control. The NTSPOMC neurons were targeted using viral vectors in a POMC-Cre mouse line to express either opto-genetic (channelrhodopsin-2) or chemo-genetic (Pharmacologically Selective Actuator Modules). Opto-genetic activation of the NTSPOMC neurons in the working heart brainstem preparation (n = 21) evoked a reliable, titratable and time-locked respiratory inhibition (120% increase in inter-breath interval) with a bradycardia (125±26 beats per minute) and augmented respiratory sinus arrhythmia (58% increase). Chemo-genetic activation of NTSPOMC neurons in vivo was anti-nociceptive in the tail flick assay (latency increased by 126±65%, pneurons were found to project to key brainstem structures involved in cardiorespiratory control (nucleus ambiguus and ventral respiratory group) and endogenous analgesia (periaqueductal gray and midline raphe). Thus the NTSPOMC neurons may be capable of tuning behaviour by an opioidergic modulation of nociceptive, respiratory and cardiac control.

  7. Large central lesions compressing the hypothalamus and brainstem. Operative approaches and combination treatment with radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Hiroshi K.; Negishi, Masatoshi; Kohga, Hideaki; Hirato, Masafumi; Ohye, Chihiro [Gunma Univ., Maebashi (Japan). School of Medicine; Shibazaki, Tohru

    1998-09-01

    A major aim of minimally invasive neurosurgery is to preserve function in the brain and cranial nerves. Based on previous results of radiosurgery for central lesions (19 craniopharyngiomas, 46 pituitary adenomas, 9 meningeal tumors), combined micro- and/or radiosurgery was applied for large lesions compressing the hypothalamus and/or brainstem. A basal interhemispheric approach via superomedial orbitotomy or a transcallosal-transforaminal approach was used for these large tumors. Tumors left behind in the hypothalamus or cavernous sinus were treated with radiosurgery using a gamma unit. Preoperative hypothalamo-pituitary functions were preserved in most of these patients. Radiosurgical results were evaluated in patients followed for more than 2 years after treatment. All 9 craniopharyngiomas decreased in size after radiosurgery, although a second treatment was required in 4 patients. All 20 pituitary adenomas were stable or decreased in size and 5 of 7 functioning adenomas showed normalized values of hormones in the serum. All 3 meningeal tumors were stable or decreased in size after treatment. No cavernous sinus symptoms developed after radiosurgery. We conclude that combined micro- and radio-neurosurgery is an effective and less invasive treatment for large central lesions compressing the hypothalamus and brainstem. (author)

  8. Inflammatory lesions of the brainstem and the cerebellopontine angle; Entzuendungen des Hirnstamms und des Kleinhirnbrueckenwinkels

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, J.; Jaeger, L. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen (Germany). Institut fuer Klinische Radiologie

    2006-03-15

    Inflammatory lesions of the brainstem and the cerebellopontine angle are often critical for the patient, because crucial neuronal and vascular structures are found in this region. The patient's prognosis mainly depends on rapid identification of the inflammation site and the radiological evaluation of the inflammation pathogenesis to develop therapeutic strategies. Therefore, cross-sectional imaging is complementary to laboratory and CSF analysis as well as biopsies. This article gives a survey of inflammatory lesions of the brainstem and the cerebellopontine angle. (orig.) [German] Entzuendliche Erkrankungen des Hirnstamms und Kleinhirnbrueckenwinkels stellen nicht selten eine kritische Situation fuer den Patienten dar, da in diesen Regionen wichtige neuronale Strukturen und Gefaesse verlaufen. Die Prognose und das weitere therapeutische Vorgehen haengen entscheidend von einer schnellen Diagnose der Entzuendungslokalisation sowie einer bildmorphologischen Einordnung der Entzuendungspathogenese ab. Folglich ergaenzt die Schnittbildgebung entscheidend die Liquoranalyse, die Biopsie und die Laboruntersuchungen. In diesem Artikel soll eine Uebersicht ueber die verschiedenen entzuendlichen Veraenderungen des Hirnstamms und Kleinhirnbrueckenwinkels gegeben werden. (orig.)

  9. Proton spectroscopy in the narcoleptic syndrome. Is there evidence of a brainstem lesion?

    Science.gov (United States)

    Ellis, C M; Simmons, A; Lemmens, G; Williams, S C; Parkes, J D

    1998-02-01

    There is controversy regarding the relationship of structural or biochemical brainstem lesions to "idiopathic" narcolepsy. Most cases of the narcoleptic syndrome are considered to be idiopathic because no structural lesion is detectable, although some cases of secondary narcolepsy are known to be associated with no structural brainstem lesions. Using proton spectroscopy, we determined levels of ventral pontine metabolite pools in 12 normal subjects and 12 subjects with idiopathic narcolepsy. REM sleep is generated in ventral pontine areas. Proton spectroscopy was used to study levels of N-acetyl aspartate (NAA) as a marker of cell mass, creatine and phosphocreatine (Cr + PCr), and choline (Cho). The intensity of the peaks, as determined by the area under the peak (AUP), was measured. The AUP correlates with the quantity of chemical present. In this study, the ratios of NAA to Cr + PCr were similar in normal subjects and in narcoleptic subjects with idiopathic narcolepsy. No differences in measured metabolic ratio were observed in subjects who slept during the scan procedure compared with those who remained awake. Subjects with "symptomatic" narcolepsy accompanied by an obvious structural brain lesion were not studied. Proton spectroscopy of the brain initiates a new kind of neurochemistry, allowing the noninvasive study of metabolic pools in the living human brain without the use of any kind of tracer or radioactive molecule. In this study, there was no evidence of cell loss in the ventral pontine areas of subjects with the narcoleptic syndrome.

  10. Motor-circuit communication matrix from spinal cord to brainstem neurons revealed by developmental origin.

    Science.gov (United States)

    Pivetta, Chiara; Esposito, Maria Soledad; Sigrist, Markus; Arber, Silvia

    2014-01-30

    Accurate motor-task execution relies on continuous comparison of planned and performed actions. Motor-output pathways establish internal circuit collaterals for this purpose. Here we focus on motor collateral organization between spinal cord and upstream neurons in the brainstem. We used a newly developed mouse genetic tool intersectionally with viruses to uncover the connectivity rules of these ascending pathways by capturing the transient expression of neuronal subpopulation determinants. We reveal a widespread and diverse network of spinal dual-axon neurons, with coincident input to forelimb motor neurons and the lateral reticular nucleus (LRN) in the brainstem. Spinal information to the LRN is not segregated by motor pool or neurotransmitter identity. Instead, it is organized according to the developmental domain origin of the progenitor cells. Thus, excerpts of most spinal information destined for action are relayed to supraspinal centers through exquisitely organized ascending connectivity modules, enabling precise communication between command and execution centers of movement. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Brainstem GLP-1 signalling contributes to cancer anorexia-cachexia syndrome in the rat.

    Science.gov (United States)

    Borner, Tito; Liberini, Claudia G; Lutz, Thomas A; Riediger, Thomas

    2018-03-15

    The cancer anorexia-cachexia syndrome (CACS) is a frequent and severe condition in cancer patients. Currently, no pharmacological treatment is approved for the therapy of CACS. Centrally, glucagon-like peptide-1 (GLP-1) is expressed in the nucleus tractus solitarii (NTS) and is implicated in malaise, nausea and food aversion. The NTS is reciprocally connected to brain sites implicated in the control of energy balance including the area postrema (AP), which mediates CACS in certain tumour models. Given the role of GLP-1 as a mediator of anorexia under acute sickness conditions, we hypothesized that brainstem GLP-1 signalling might play a role in the mediation of CACS. Using hepatoma tumour-bearing (TB) rats, we first tested whether the chronic delivery of the GLP-1R antagonist exendin-9 (Ex-9) into the fourth ventricle attenuates CACS. Second, we investigated whether a genetic knockdown of GLP-1 expression in the NTS ameliorates CACS. Ex-9 attenuated anorexia, body weight loss, muscle and fat depletion compared to TB controls. Similarly, TB animals with a knockdown of GLP-1 expression in the NTS had higher food intake, reduced body weight loss, and higher lean and fat mass compared to TB controls. Our study identifies brainstem GLP-1 as crucial mediator of CACS in hepatoma TB rats. The GLP-1R represents a promising target against CACS and possibly other forms of disease-related anorexia/cachexia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Immunohistochemical Mapping of TRK-Fused Gene Products in the Rat Brainstem

    International Nuclear Information System (INIS)

    Takeuchi, Shigeko; Masuda, Chiaki; Maebayashi, Hisae; Tooyama, Ikuo

    2012-01-01

    The TRK-fused gene (TFG in human, Tfg in rat) was originally identified in human papillary thyroid cancer as a chimeric form of the NTRK1 gene. It was since reported that the gene product (TFG) plays a role in regulating phosphotyrosine-specific phosphatase-1 activity. As shown in the accompanying paper, we produced an antibody to rat TFG and used it to localize TFG to selected neurons in specific regions. In the present study, we mapped the TFG-positive neurons in the brainstem, cerebellum, and spinal cord of rats. In the brainstem, neurons intensely positive for TFG were distributed in the raphe nuclei, the gigantocellular reticular nucleus, the reticulotegmental nucleus of the pons, and some cranial nerve nuclei such as the trigeminal nuclei, the vestibulocochlear nuclei, and the dorsal motor nucleus of the vagus. Purkinje cells in the cerebellum and motor neurons in the spinal anterior horn were also positive for TFG. These results provide fundamental data for studying the functions of TFG in the brain

  13. Large central lesions compressing the hypothalamus and brainstem. Operative approaches and combination treatment with radiosurgery

    International Nuclear Information System (INIS)

    Inoue, Hiroshi K.; Negishi, Masatoshi; Kohga, Hideaki; Hirato, Masafumi; Ohye, Chihiro; Shibazaki, Tohru

    1998-01-01

    A major aim of minimally invasive neurosurgery is to preserve function in the brain and cranial nerves. Based on previous results of radiosurgery for central lesions (19 craniopharyngiomas, 46 pituitary adenomas, 9 meningeal tumors), combined micro- and/or radiosurgery was applied for large lesions compressing the hypothalamus and/or brainstem. A basal interhemispheric approach via superomedial orbitotomy or a transcallosal-transforaminal approach was used for these large tumors. Tumors left behind in the hypothalamus or cavernous sinus were treated with radiosurgery using a gamma unit. Preoperative hypothalamo-pituitary functions were preserved in most of these patients. Radiosurgical results were evaluated in patients followed for more than 2 years after treatment. All 9 craniopharyngiomas decreased in size after radiosurgery, although a second treatment was required in 4 patients. All 20 pituitary adenomas were stable or decreased in size and 5 of 7 functioning adenomas showed normalized values of hormones in the serum. All 3 meningeal tumors were stable or decreased in size after treatment. No cavernous sinus symptoms developed after radiosurgery. We conclude that combined micro- and radio-neurosurgery is an effective and less invasive treatment for large central lesions compressing the hypothalamus and brainstem. (author)

  14. Brainstem auditory evoked potentials in healthy cats recorded with surface electrodes

    Directory of Open Access Journals (Sweden)

    Mihai Musteata

    2013-01-01

    Full Text Available The aim of this study was to evaluate the brainstem auditory evoked potentials of seven healthy cats, using surface electrodes. Latencies of waves I, III and V, and intervals I–III, I–V and III–V were recorded. Monaural and binaural stimulation of the cats were done with sounds ranging between 40 and 90 decibel Sound Pressure Level. All latencies were lower than those described in previous studies, where needle electrodes were used. In the case of binaural stimulation, latencies of waves III and V were greater compared to those obtained for monaural stimulation (P P > 0.05. Regardless of the sound intensity, the interwave latency was constant (P > 0.05. Interestingly, no differences were noticed for latencies of waves III and V when sound intensity was higher than 80dB SPL. This study completes the knowledge in the field of electrophysiology and shows that the brainstem auditory evoked potentials in cats using surface electrodes is a viable method to record the transmission of auditory information. That can be faithfully used in clinical practice, when small changes of latency values may be an objective factor in health status evaluation.

  15. Study of automated segmentation of the cerebellum and brainstem on brain MR images

    International Nuclear Information System (INIS)

    Hayashi, Norio; Matsuura, Yukihiro; Sanada, Shigeru; Suzuki, Masayuki

    2005-01-01

    MR imaging is an important method for diagnosing abnormalities of the brain. This paper presents an automated method to segment the cerebellum and brainstem for brain MR images. MR images were obtained from 10 normal subjects (male 4, female 6; 22-75 years old, average 31.0 years) and 15 patients with brain atrophy (male 3, female 12; 62-85 years of age, average 76.0 years). The automated method consisted of the following four steps: segmentation of the brain on original images, detection of an upper plane of the cerebellum using the Hough transform, correction of the plane using three-dimensional (3D) information, and segmentation of the cerebellum and brainstem using the plane. The results indicated that the regions obtained by the automated method were visually similar to those obtained by a manual method. The average rates of coincidence between the automated method and manual method were 83.0±9.0% in normal subjects and 86.4±3.6% in patients. (author)

  16. MRI findings of the brainstem of the neuro-Behcet syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Fujiki, Naoto; Tashiro, Kunio; Yamada, Takayoshi; Ito, Kazunori; Honma, Sanae; Doi, Shizuki; Moriwaka, Fumio

    1987-10-01

    We reported three cases of neuro-Behcet's syndrome which showed brainstem lesions on MRI compatible with the clinical symptoms. In Case 1, MRI showed a large, abnormal signal-intensity area in the pons and small, abnormal signal-intensity areas at the right cerebral peduncle, the bilateral basal ganglia, and the left thalamus. These lesions disappeared on MRI, in accordance with the remission of clinical symptoms. On the other hand, CT showed no positive findings. In Case 2, an abnormal signal-intensity area was disclosed at the left cerebral peduncle on MRI. This lesion was also identified on the CT scan. In Case 3, an abnormal signal-intensity area was present in the pons on MRI. In this case, CT showed no positive findings. In Cases 2 and 3, these lesions seemed to represent inflammatory or necrotic areas attributable to vasculitis;however, the extensive brainstem lesion seen on the MRI of Case 1 was a quite unique finding, for which no exact pathophysiological explanation is possible at the present time.

  17. The transcriptional regulatory network in the drought response and its crosstalk in abiotic stress responses including drought, cold and heat

    Directory of Open Access Journals (Sweden)

    Kazuo eNakashima

    2014-05-01

    Full Text Available Drought negatively impacts plant growth and the productivity of crops around the world. Understanding the molecular mechanisms in the drought response is important for improvement of drought tolerance using molecular techniques. In plants, abscisic acid (ABA is accumulated under osmotic stress conditions caused by drought, and has a key role in stress responses and tolerance. Comprehensive molecular analyses have shown that ABA regulates the expression of many genes under osmotic stress conditions, and the ABA-responsive element (ABRE is the major cis-element for ABA-responsive gene expression. Transcription factors (TFs are master regulators of gene expression. ABRE-binding protein (AREB and ABRE-binding factor (ABF TFs control gene expression in an ABA-dependent manner. SNF1-related protein kinases 2, group A 2C-type protein phosphatases, and ABA receptors were shown to control the ABA signaling pathway. ABA-independent signaling pathways such as dehydration-responsive element-binding protein (DREB TFs and NAC TFs are also involved in stress responses including drought, heat and cold. Recent studies have suggested that there are interactions between the major ABA signaling pathway and other signaling factors in stress responses. The important roles of these transcription factors in crosstalk among abiotic stress responses will be discussed. Control of ABA or stress signaling factor expression can improve tolerance to environmental stresses. Recent studies using crops have shown that stress-specific overexpression of TFs improves drought tolerance and grain yield compared with controls in the field.

  18. The transcriptional regulatory network in the drought response and its crosstalk in abiotic stress responses including drought, cold, and heat.

    Science.gov (United States)

    Nakashima, Kazuo; Yamaguchi-Shinozaki, Kazuko; Shinozaki, Kazuo

    2014-01-01

    Drought negatively impacts plant growth and the productivity of crops around the world. Understanding the molecular mechanisms in the drought response is important for improvement of drought tolerance using molecular techniques. In plants, abscisic acid (ABA) is accumulated under osmotic stress conditions caused by drought, and has a key role in stress responses and tolerance. Comprehensive molecular analyses have shown that ABA regulates the expression of many genes under osmotic stress conditions, and the ABA-responsive element (ABRE) is the major cis-element for ABA-responsive gene expression. Transcription factors (TFs) are master regulators of gene expression. ABRE-binding protein and ABRE-binding factor TFs control gene expression in an ABA-dependent manner. SNF1-related protein kinases 2, group A 2C-type protein phosphatases, and ABA receptors were shown to control the ABA signaling pathway. ABA-independent signaling pathways such as dehydration-responsive element-binding protein TFs and NAC TFs are also involved in stress responses including drought, heat, and cold. Recent studies have suggested that there are interactions between the major ABA signaling pathway and other signaling factors in stress responses. The important roles of these TFs in crosstalk among abiotic stress responses will be discussed. Control of ABA or stress signaling factor expression can improve tolerance to environmental stresses. Recent studies using crops have shown that stress-specific overexpression of TFs improves drought tolerance and grain yield compared with controls in the field.

  19. The relationship of age, gender, and IQ with the brainstem and thalamus in healthy children and adolescents: a magnetic resonance imaging volumetric study.

    Science.gov (United States)

    Xie, Yuhuan; Chen, Yian Ann; De Bellis, Michael D

    2012-03-01

    In healthy children, there is a paucity of information on the growth of the brainstem and thalamus measured anatomically magnetic resonance imaging. The relations of age, gender, and age by gender with brainstem and thalamus volumes were analyzed from magnetic resonance brain images of 122 healthy children and adolescents (62 males, 60 females; ages 4 to 17). Results showed that age is a significant predictor of brainstem and thalamus volumes. The volume of the brainstem increases with age, while thalamus volume declines with age. The volume of the right thalamus is significantly larger than that of the left in both genders, with greater rightward asymmetry and greater thalamus to grey matter ratio in females. Males have larger brainstems, but these differences are not significant when covarying for cerebral volume. Larger thalami were associated with higher Verbal IQ. These normative pediatric data are of value to researchers who study these regions in neurodevelopmental disorders.

  20. Synaptic plasticity in the medial vestibular nuclei: role of glutamate receptors and retrograde messengers in rat brainstem slices.

    Science.gov (United States)

    Grassi, S; Pettorossi, V E

    2001-08-01

    The analysis of cellular-molecular events mediating synaptic plasticity within vestibular nuclei is an attempt to explain the mechanisms underlying vestibular plasticity phenomena. The present review is meant to illustrate the main results, obtained in vitro, on the mechanisms underlying long-term changes in synaptic strength within the medial vestibular nuclei. The synaptic plasticity phenomena taking place at the level of vestibular nuclei could be useful for adapting and consolidating the efficacy of vestibular neuron responsiveness to environmental requirements, as during visuo-vestibular recalibration and vestibular compensation. Following a general introduction on the most salient features of vestibular compensation and visuo-vestibular adaptation, which are two plastic events involving neuronal circuitry within the medial vestibular nuclei, the second and third sections describe the results from rat brainstem slice studies, demonstrating the possibility to induce long-term potentiation and depression in the medial vestibular nuclei, following high frequency stimulation of the primary vestibular afferents. In particular the mechanisms sustaining the induction and expression of vestibular long-term potentiation and depression, such as the role of various glutamate receptors and retrograde messengers have been described. The relevant role of the interaction between the platelet-activating factor, acting as a retrograde messenger, and the presynaptic metabotropic glutamate receptors, in determining the full expression of vestibular long-term potentiation is also underlined. In addition, the mechanisms involved in vestibular long-term potentiation have been compared with those leading to long-term potentiation in the hippocampus to emphasize the most significant differences emerging from vestibular studies. The fourth part, describes recent results demonstrating the essential role of nitric oxide, another retrograde messenger, in the induction of vestibular

  1. Optogenetic stimulation of locus ceruleus neurons augments inhibitory transmission to parasympathetic cardiac vagal neurons via activation of brainstem α1 and β1 receptors.

    Science.gov (United States)

    Wang, Xin; Piñol, Ramón A; Byrne, Peter; Mendelowitz, David

    2014-04-30

    Locus ceruleus (LC) noradrenergic neurons are critical in generating alertness. In addition to inducing cortical arousal, the LC also orchestrates changes in accompanying autonomic system function that compliments increased attention, such as during stress, excitation, and/or exposure to averse or novel stimuli. Although the association between arousal and increased heart rate is well accepted, the neurobiological link between the LC and parasympathetic neurons that control heart rate has not been identified. In this study, we test directly whether activation of noradrenergic neurons in the LC influences brainstem parasympathetic cardiac vagal neurons (CVNs). CVNs were identified in transgenic mice that express channel-rhodopsin-2 (ChR2) in LC tyrosine hydroxylase neurons. Photoactivation evoked a rapid depolarization, increased firing, and excitatory inward currents in ChR2-expressing neurons in the LC. Photostimulation of LC neurons did not alter excitatory currents, but increased inhibitory neurotransmission to CVNs. Optogenetic activation of LC neurons increased the frequency of isolated glycinergic IPSCs by 27 ± 8% (p = 0.003, n = 26) and augmented GABAergic IPSCs in CVNs by 21 ± 5% (p = 0.001, n = 26). Inhibiting α1, but not α2, receptors blocked the evoked responses. Inhibiting β1 receptors prevented the increase in glycinergic, but not GABAergic, IPSCs in CVNs. This study demonstrates LC noradrenergic neurons inhibit the brainstem CVNs that generate parasympathetic activity to the heart. This inhibition of CVNs would increase heart rate and risks associated with tachycardia. The receptors activated within this pathway, α1 and/or β1 receptors, are targets for clinically prescribed antagonists that promote slower, cardioprotective heart rates during heightened vigilant states.

  2. Differential actions of orexin receptors in brainstem cholinergic and monoaminergic neurons revealed by receptor knockouts: implications for orexinergic signaling in arousal and narcolepsy

    Directory of Open Access Journals (Sweden)

    Kristi A Kohlmeier

    2013-12-01

    Full Text Available Orexin neuropeptides influence multiple homeostatic functions and play an essential role in the expression of normal sleep-wake behavior. While their two known receptors (OX1 and OX2 are targets for novel pharmacotherapeutics, the actions mediated by each receptor remain largely unexplored. Using brain slices from mice constitutively lacking either receptor, we used whole-cell and Ca2+ imaging methods to delineate the cellular actions of each receptor within cholinergic (laterodorsal tegmental nucleus; LDT and monoaminergic (dorsal raphe; DR and locus coeruleus; LC brainstem nuclei – where orexins promote arousal and suppress REM sleep. In slices from OX2-/- mice, orexin-A (300 nM elicited wild-type responses in LDT, DR and LC neurons consisting of a depolarizing current and augmented voltage-dependent Ca2+ transients. In slices from OX1-/- mice, the depolarizing current was absent in LDT and LC neurons and was attenuated in DR neurons, although Ca2+-transients were still augmented. Since orexin-A produced neither of these actions in slices lacking both receptors, our findings suggest that orexin-mediated depolarization is mediated by both receptors in DR, but is exclusively mediated by OX1 in LDT and LC neurons, even though OX2 is present and OX2 mRNA appears elevated in brainstems from OX1-/- mice. Considering published behavioral data, these findings support a model in which orexin-mediated excitation of mesopontine cholinergic and monoaminergic neurons contributes little to stabilizing spontaneous waking and sleep bouts, but functions in context-dependent arousal and helps restrict muscle atonia to REM sleep. The augmented Ca2± transients mediated by both receptors appeared mediated by influx via L-type Ca2+ channels, which is often linked to transcriptional signaling. This could provide an adaptive signal to compensate for receptor loss or prolonged antagonism and may contribute to the reduced severity of narcolepsy in single receptor

  3. Prescription dose and fractionation predict improved survival after stereotactic radiotherapy for brainstem metastases

    Directory of Open Access Journals (Sweden)

    Leeman Jonathan E

    2012-07-01

    Full Text Available Abstract Background Brainstem metastases represent an uncommon clinical presentation that is associated with a poor prognosis. Treatment options are limited given the unacceptable risks associated with surgical resection in this location. However, without local control, symptoms including progressive cranial nerve dysfunction are frequently observed. The objective of this study was to determine the outcomes associated with linear accelerator-based stereotactic radiotherapy or radiosurgery (SRT/SRS of brainstem metastases. Methods We retrospectively reviewed 38 tumors in 36 patients treated with SRT/SRS between February 2003 and December 2011. Treatment was delivered with the Cyberknife™ or Trilogy™ radiosurgical systems. The median age of patients was 62 (range: 28–89. Primary pathologies included 14 lung, 7 breast, 4 colon and 11 others. Sixteen patients (44% had received whole brain radiation therapy (WBRT prior to SRT/SRS; ten had received prior SRT/SRS at a different site (28%. The median tumor volume was 0.94 cm3 (range: 0.01-4.2 with a median prescription dose of 17 Gy (range: 12–24 delivered in 1–5 fractions. Results Median follow-up for the cohort was 3.2 months (range: 0.4-20.6. Nineteen patients (52% had an MRI follow-up available for review. Of these, one patient experienced local failure corresponding to an actuarial 6-month local control of 93%. Fifteen of the patients with available follow-up imaging (79% experienced intracranial failure outside of the treatment volume. The median time to distant intracranial failure was 2.1 months. Six of the 15 patients with distant intracranial failure (40% had received previous WBRT. The actuarial overall survival rates at 6- and 12-months were 27% and 8%, respectively. Predictors of survival included Graded Prognostic Assessment (GPA score, greater number of treatment fractions, and higher prescription dose. Three patients experienced acute treatment-related toxicity consisting of

  4. Production of bioenergy in anaerobic baffled reactor (ABR) and sludge blanket (UASB) in the treatment os swine waste water; Producao de bioenergia em reatores anaerobios compartimentado (RAC) e de manta de lodo (UASB) no tratamento de efluentes de suinocultura

    Energy Technology Data Exchange (ETDEWEB)

    Moterani, Fabricio; Pereira, Erlon Lopes; Campos, Claudio M.M. [Universidade Federal de Lavras (DEG/UFLA), MG (Brazil). Dept. de Engenharia], email: fabricio_moterani@yahoo.com.br

    2011-07-01

    The biogas is obtained in the processes of degradation of organic matter by the action of bacterial consortium in the environment. The aim of this study was to evaluate the biogas production in anaerobic UASB and ABR in swine wastewater treatment. For this we used the theoretical estimated and actual production of biogas measured by anaerobic gasometers installed in the units. Methane was determined by gas chromatography (GC) and its theoretical output was 66 LCH4 kgSVT d{sup -1} and 11.9 LCH4 kgSVT d{sup -1} and 24.7 m{sup 3} d{sup -1} and 5.4 m{sup 3} d{sup -1} to ABR and UASB, respectively. Regarding the actual production of biogas in the reactor provided by the gas tank, found the values of 1,166.4 m{sup 3}; 0.1 m{sup 3}; 27.4 m{sup 3} and 12,598.5 m{sup 3} of biogas for compartments 1, 2 and 3 and ABR for the UASB reactor, respectively, totaling, production of 13,792.4 m{sup 3} in the units together, with an average of 113 m{sup 3} of biogas per day. But, it concludes with this research that the use of effluent from produce energy through biogas in swine farming is effective, which can be used in rural productive system itself. (author)

  5. Collateralization of descending spinal pathways from red nucleus and other brainstem cell groups in rat, cat and monkey

    NARCIS (Netherlands)

    A.M. Huisman (Margriet)

    1983-01-01

    textabstractThe somatotopically organized rubrospinal pathway is the major component of the laterally descending brainstem pathways, and is especially involved in steering of fractionated movements of the distal parts of the limbs. Electrophysiological studies in cat showed that this fiber

  6. Anatomical parcellation of the brainstem and cerebellar white matter: a preliminary probabilistic tractography study at 3 T

    International Nuclear Information System (INIS)

    Habas, Christophe; Cabanis, Emmanuel A.

    2007-01-01

    The aims of this study were: (1) to test whether higher spatial resolution diffusion tensor images and a higher field strength (3 T) enable a more accurate delineation of the anatomical tract within the brainstem, and, in particular, (2) to try to distinguish the different components of the corticopontocerebellar paths in terms of their cortical origins. The main tracts of the brainstem of four volunteers were studied at 3 T using a probabilistic diffusion tensor imaging (DTI) axonal tracking. The resulting tractograms enabled anatomical well-delineated structures to be identified on the diffusion tensor coloured images. We tracked corticopontine, corticospinal, central tegmental, inferior and superior cerebellopeduncular, transverse, medial lemniscal and, possibly, longitudinal medial fibres. Moreover, DTI tracking allowed a broad delineation of the corticopontocerebellar paths. Diffusion tensor coloured images allow a rapid and reliable access to the white matter broad parcellation of the brainstem and of the cerebellum, which can be completed by fibre tracking. However, a more accurate and exhaustive depiction of the anatomical connectivity within the brainstem requires the application of more sophisticated techniques and tractography algorithms, such as diffusion spectrum imaging. (orig.)

  7. Study of the correlation of brainstem auditory evoked potentials and magnetic resonance imaging in children with spastic cerebral palsy

    International Nuclear Information System (INIS)

    Fobe, Lisete Pessoa de Oliveira

    1999-01-01

    Central auditory evaluation in 21 children with cerebral palsy was done with brainstem auditory evoked potentials (BAEP) and correlated with brain magnetic resonance imaging findings (MRI); 12 boys and 9 girls between 5 and 12 years old were studied. All children had follow-up at the Institute of Orthopedics and Traumatology of Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo. The control group was done with 17 children, 10 boys and 7 girls (mean age 8.06 years, SD 2.27 years). The BAEP abnormalities were: decrease of latency of wave V; decrease of latency III-V and I-IV intervals at the right side. All patients has MRI supratentorial abnormalities and 11 had brainstem atrophy. The MRI pathologic findings were: ventricular enlargement (n=17 or 80.95%), cortical/subcortical atrophy (n=15 or 71.42%), left brainstem atrophy (n=11 or 52.38%), periventricular leukomalacia (n=10 or 47.61%), infarction in the left middle cerebral artery territory (n=6 or 28.57%), and malformations such as schizencephaly and colpocephaly (n=5 or 23.80%). The findings of the decrease latencies in children with cerebral palsy suggest the contribution of decussating auditory fibers at the lower and upper pons and midbrain, the lack of homogeneity of the surrounding volume of the conductor fibres and the presence of several concurrently active potential generators sources, should be facilitating mechanisms for the nervous input to brainstem. (author)

  8. Study of the correlation of brainstem auditory evoked potentials and magnetic resonance imaging in children with spastic cerebral palsy

    Energy Technology Data Exchange (ETDEWEB)

    Fobe, Lisete Pessoa de Oliveira [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina]. E-mail: lispessoa@yahoo.com

    1999-12-01

    Central auditory evaluation in 21 children with cerebral palsy was done with brainstem auditory evoked potentials (BAEP) and correlated with brain magnetic resonance imaging findings (MRI); 12 boys and 9 girls between 5 and 12 years old were studied. All children had follow-up at the Institute of Orthopedics and Traumatology of Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo. The control group was done with 17 children, 10 boys and 7 girls (mean age 8.06 years, SD 2.27 years). The BAEP abnormalities were: decrease of latency of wave V; decrease of latency III-V and I-IV intervals at the right side. All patients has MRI supratentorial abnormalities and 11 had brainstem atrophy. The MRI pathologic findings were: ventricular enlargement (n=17 or 80.95%), cortical/subcortical atrophy (n=15 or 71.42%), left brainstem atrophy (n=11 or 52.38%), periventricular leukomalacia (n=10 or 47.61%), infarction in the left middle cerebral artery territory (n=6 or 28.57%), and malformations such as schizencephaly and colpocephaly (n=5 or 23.80%). The findings of the decrease latencies in children with cerebral palsy suggest the contribution of decussating auditory fibers at the lower and upper pons and midbrain, the lack of homogeneity of the surrounding volume of the conductor fibres and the presence of several concurrently active potential generators sources, should be facilitating mechanisms for the nervous input to brainstem. (author)

  9. Anatomical parcellation of the brainstem and cerebellar white matter: a preliminary probabilistic tractography study at 3 T

    Energy Technology Data Exchange (ETDEWEB)

    Habas, Christophe; Cabanis, Emmanuel A. [UPMC Paris 6, Service de NeuroImagerie, Hopital des Quinze-Vingts, Paris (France)

    2007-10-15

    The aims of this study were: (1) to test whether higher spatial resolution diffusion tensor images and a higher field strength (3 T) enable a more accurate delineation of the anatomical tract within the brainstem, and, in particular, (2) to try to distinguish the different components of the corticopontocerebellar paths in terms of their cortical origins. The main tracts of the brainstem of four volunteers were studied at 3 T using a probabilistic diffusion tensor imaging (DTI) axonal tracking. The resulting tractograms enabled anatomical well-delineated structures to be identified on the diffusion tensor coloured images. We tracked corticopontine, corticospinal, central tegmental, inferior and superior cerebellopeduncular, transverse, medial lemniscal and, possibly, longitudinal medial fibres. Moreover, DTI tracking allowed a broad delineation of the corticopontocerebellar paths. Diffusion tensor coloured images allow a rapid and reliable access to the white matter broad parcellation of the brainstem and of the cerebellum, which can be completed by fibre tracking. However, a more accurate and exhaustive depiction of the anatomical connectivity within the brainstem requires the application of more sophisticated techniques and tractography algorithms, such as diffusion spectrum imaging. (orig.)

  10. The analgesic agent tapentadol inhibits calcitonin gene-related peptide release from isolated rat brainstem via a serotonergic mechanism.

    Science.gov (United States)

    Greco, Maria Cristina; Navarra, Pierluigi; Tringali, Giuseppe

    2016-01-15

    In this study we tested the hypothesis that tapentadol inhibits GGRP release from the rat brainstem through a mechanism mediated by the inhibition of NA reuptake; as a second alternative hypothesis, we investigated whether tapentadol inhibits GGRP release via the inhibition of 5-HT reuptake. Rat brainstems were explanted and incubated in short-term experiments. CGRP released in the incubation medium was taken as a marker of CGRP release from the central terminals of trigeminal neurons within the brainstem. CGRP levels were measured by radioimmunoassay under basal conditions or in the presence of tapentadol; NA, 5-HT, clonidine, yohimbine and ondansetron were used as pharmacological tools to investigate the action mechanism of tapentadol. The α2-antagonist yohimbine failed to counteract the effects of tapentadol. Moreover, neither NA nor the α2-agonist clonidine per se inhibited K(+)-stimulated CGRP release, thereby indicating that the effects of tapentadol are nor mediated through the block of NA reuptake. Further experiments showed that 5-HT and tramadol, which inhibits both NA and 5-HT reuptake, significantly reduced K(+)-stimulated CGRP release. Moreover, the 5-HT3 antagonist ondansetron was able to counteract the effects of tapentadol in this system. This study provided pharmacological evidence that tapentadol inhibits stimulated CGRP release from the rat brainstem in vitro through a mechanism involving an increase in 5-HT levels in the system and the subsequent activation of 5-HT3 receptors. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Astrocyte-secreted factors modulate a gradient of primary dendritic arbors in nucleus laminaris of the avian auditory brainstem.

    Directory of Open Access Journals (Sweden)

    Matthew J Korn

    Full Text Available Neurons in nucleus laminaris (NL receive binaural, tonotopically matched input from nucleus magnocelluaris (NM onto bitufted dendrites that display a gradient of dendritic arbor size. These features improve computation of interaural time differences, which are used to determine the locations of sound sources. The dendritic gradient emerges following a period of significant reorganization at embryonic day 15 (E15, which coincides with the emergence of astrocytes that express glial fibrillary acidic protein (GFAP in the auditory brainstem. The major changes include a loss of total dendritic length, a systematic loss of primary dendrites along the tonotopic axis, and lengthening of primary dendrites on caudolateral NL neurons. Here we have tested whether astrocyte-derived molecules contribute to these changes in dendritic morphology. We used an organotypic brainstem slice preparation to perform repeated imaging of individual dye-filled NL neurons to determine the effects of astrocyte-conditioned medium (ACM on dendritic morphology. We found that treatment with ACM induced a decrease in the number of primary dendrites in a tonotopically graded manner similar to that observed during normal development. Our data introduce a new interaction between astrocytes and neurons in the auditory brainstem and suggest that these astrocytes influence multiple aspects of auditory brainstem maturation.

  12. Axonal sprouting of a brainstem-spinal pathway after estrogen administration in the adult female rhesus monkey

    NARCIS (Netherlands)

    Vanderhorst, VGJM; Terasawa, E; Ralston, HJ

    2002-01-01

    The nucleus retroambiguus (NRA) is located in the caudal medulla oblongata and contains premotor neurons that project to motoneuronal cell groups in the brainstem and spinal cord. NRA projections to the lumbosacral cord are species specific and might be involved in mating behavior. In the female

  13. Interactions between Brainstem Noradrenergic Neurons and the Nucleus Accumbens Shell in Modulating Memory for Emotionally Arousing Events

    Science.gov (United States)

    Kerfoot, Erin C.; Williams, Cedric L.

    2011-01-01

    The nucleus accumbens shell (NAC) receives axons containing dopamine-[beta]-hydroxylase that originate from brainstem neurons in the nucleus of the solitary tract (NTS). Recent findings show that memory enhancement produced by stimulating NTS neurons after learning may involve interactions with the NAC. However, it is unclear whether these…

  14. Diffuse and focal presentations of brainstem tumors in children: the images and the prognostic value; Presentacion difusa o focal de los tumores troncoencefalicos en los ninos: imagen y valor pronostico

    Energy Technology Data Exchange (ETDEWEB)

    Menor, F.; Canete, A.; Romero, M. J.; Trilles, L.; Carvajal, E. [Hospital Universitario La Fe. Valencia (Spain); Marti-Bonmati, L. [Hospital Universitario Dr. Peset. Valencia (Spain)

    2000-07-01

    To determine whether the presentation of brainstem tumors as diffuse or focal lesions showed any prognostic value in children. A retrospective review was carried out of the neuroradiological findings in 43 children with brainstem tumors, all of whom underwent computed tomography (CT) and 31 of whom underwent magnetic resonance (MR). The diffuse tumors (n=20) were all located in the pons, spreading to mesencephalon in 6 cases and to medulla oblongata in 1, and exhibiting exophytic growth, preferentially to the prepontine cistern. They presented homogeneous low attenuation in CT (90%) and decrease/increased signal intensity in T1/T2-weighted MR images (91.6%). Contrast uptake was observed in 20% of cases, with agreement between CT and MR. The patients showed a good initial response to treatment (70%), a high rate of relapse (80%) and a 5-year survival of 12%. The focal tumors were located in the pons (11 cases, spreading to the medulla oblongata in 2), mesencephalon (11 cases, 9 tectal and 2 peduncular) and medulla oblongata (1 case), and exhibited exophytic growth predominantly to the pontocerebellar junction and to the cerebellar peduncles. They showed a certain tendency toward heterogeneity (21.7%), toward isoattenuation in CT (47.8%) and isointensity in T1-weighted MR images (26.3%). CT showed a rate of tumor uptake of 26%, while the rate of contrast iptake was 58% MR. Fifty percent of these lesions responded well to therapy, with a recurrence rate of 28% and 4-year survival of 63%. Neuroimaging helps to define two basic patterns in brainstem tumors that play a role in prognosis. The diffuse tumor, which characteristically shows a good initial response to therapy, has a worse prognosis, probably reflecting its histological aggressiveness. (Author) 21 refs.

  15. Guillain-Barré Syndrome with Absent Brainstem Reflexes: a Case Report

    Directory of Open Access Journals (Sweden)

    Susana Gordon Chaves

    2014-02-01

    Full Text Available A 41-year-old man was admitted to an intensive care unit following respiratory arrest. One day prior to admission, he had complaints of nausea and pain involving lower limbs. On the night of admission he developed diplopia, dysphagia, and rapidly progressive quadriparesis. He developed respiratory failure requiring mechanical lung ventilation 24 hours later. On the fifth day of hospital stay the patient became comatose with absent brainstem reflexes and appeared to be brain dead. The cerebrospinal fluid showed albuminocytological dissociation. The electroencephalogram revealed an alpha rhythmical activity. The electrophysiological evaluation revealed an inexcitability of all nerves. Guillain-Barré syndrome was suspected. With supportive treatment the patient had a remarkable recovery and now is able to independently conduct his daily activities.

  16. Axonal Spheroid Accumulation In the Brainstem and Spinal Cord of A Young Angus Cow with Ataxia.

    Science.gov (United States)

    Hanshaw, D M; Finnie, J W; Manavis, J; Kessell, A E

    2015-08-01

    An 18-month-old Angus cow presented with rapidly developing ataxia and subsequently died. The finding of large numbers of axonal spheroids in brainstem nuclei and spinal cord grey matter, bilaterally symmetrical in distribution, was consistent with a histopathological diagnosis of neuroaxonal dystrophy (NAD). Most of the axonal swellings were immunopositive to amyloid precursor protein, suggesting that interruption to axonal flow was important in their genesis. The topographical distribution of axonal spheroids in the brain and spinal cord in this bovine case closely resembled that found in the ovine neurodegenerative disorder termed NAD, in which axonal swellings are the major pathological feature. This appears to be the first reported case of this type of NAD in cattle. The aetiology of the spheroidal aggregations in this case was not determined. There was no evidence from the case history or neuropathology to indicate whether the axonal spheroids in this case involved an acquired or heritable aetiology. © 2015 Australian Veterinary Association.

  17. AMPD2 regulates GTP synthesis and is mutated in a potentially treatable neurodegenerative brainstem disorder.

    Science.gov (United States)

    Akizu, Naiara; Cantagrel, Vincent; Schroth, Jana; Cai, Na; Vaux, Keith; McCloskey, Douglas; Naviaux, Robert K; Van Vleet, Jeremy; Fenstermaker, Ali G; Silhavy, Jennifer L; Scheliga, Judith S; Toyama, Keiko; Morisaki, Hiroko; Sonmez, Fatma M; Celep, Figen; Oraby, Azza; Zaki, Maha S; Al-Baradie, Raidah; Faqeih, Eissa A; Saleh, Mohammed A M; Spencer, Emily; Rosti, Rasim Ozgur; Scott, Eric; Nickerson, Elizabeth; Gabriel, Stacey; Morisaki, Takayuki; Holmes, Edward W; Gleeson, Joseph G

    2013-08-01

    Purine biosynthesis and metabolism, conserved in all living organisms, is essential for cellular energy homeostasis and nucleic acid synthesis. The de novo synthesis of purine precursors is under tight negative feedback regulation mediated by adenosine and guanine nucleotides. We describe a distinct early-onset neurodegenerative condition resulting from mutations in the adenosine monophosphate deaminase 2 gene (AMPD2). Patients have characteristic brain imaging features of pontocerebellar hypoplasia (PCH) due to loss of brainstem and cerebellar parenchyma. We found that AMPD2 plays an evolutionary conserved role in the maintenance of cellular guanine nucleotide pools by regulating the feedback inhibition of adenosine derivatives on de novo purine synthesis. AMPD2 deficiency results in defective GTP-dependent initiation of protein translation, which can be rescued by administration of purine precursors. These data suggest AMPD2-related PCH as a potentially treatable early-onset neurodegenerative disease. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. AMPD2 Regulates GTP Synthesis and is Mutated in a Potentially-Treatable Neurodegenerative Brainstem Disorder

    Science.gov (United States)

    Akizu, Naiara; Cantagrel, Vincent; Schroth, Jana; Cai, Na; Vaux, Keith; McCloskey, Douglas; Naviaux, Robert K.; Vleet, Jeremy Van; Fenstermaker, Ali G.; Silhavy, Jennifer L.; Scheliga, Judith S.; Toyama, Keiko; Morisaki, Hiroko; Sonmez, Fatma Mujgan; Celep, Figen; Oraby, Azza; Zaki, Maha S.; Al-Baradie, Raidah; Faqeih, Eissa; Saleh, Mohammad; Spencer, Emily; Rosti, Rasim Ozgur; Scott, Eric; Nickerson, Elizabeth; Gabriel, Stacey; Morisaki, Takayuki; Holmes, Edward W.; Gleeson, Joseph G.

    2013-01-01

    Purine biosynthesis and metabolism, conserved in all living organisms, is essential for cellular energy homeostasis and nucleic acids synthesis. The de novo synthesis of purine precursors is under tight negative feedback regulation mediated by adenosine and guanine nucleotides. We describe a new distinct early-onset neurodegenerative condition resulting from mutations in the adenosine monophosphate deaminase 2 gene (AMPD2). Patients have characteristic brain imaging features of pontocerebellar hypoplasia (PCH), due to loss of brainstem and cerebellar parenchyma. We found that AMPD2 plays an evolutionary conserved role in the maintenance of cellular guanine nucleotide pools by regulating the feedback inhibition of adenosine derivatives on de novo purine synthesis. AMPD2 deficiency results in defective GTP-dependent initiation of protein translation, which can be rescued by administration of purine precursors. These data suggest AMPD2-related PCH as a new, potentially treatable early-onset neurodegenerative disease. PMID:23911318

  19. Painful tonic spasms and brainstem involvement in a patient with neuromyelitis optica spectrum disorder.

    Science.gov (United States)

    Roman-Filip, Corina; Ungureanu, Aurelian; Cernuşcă-Miţaru, Mihaela

    2016-01-01

    Neuromyelitis optica (NMO) is an inflammatory-demyelinating disease of the central nervous system classically characterized by optic neuritis and severe myelitis. New diagnostic criteria defined neuromyelitis optica spectrum disorder as limited forms of NMO or diverse neurologic presentations in the presence of specific antiaquaporin-4 antibodies. We report the case of a 57-year-old woman admitted in our department for recurrent attacks of optic neuritis, tetraparesis with severe painful tonic spasms of the left limbs and brainstem involvement. Painful tonic spasms have been described as movement disorders associated with multiple sclerosis, but a growing number of reports describe them in cases of NMO. Copyright © 2015 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  20. A case of neuro-Behcet syndrome with brainstem lesions confirmed by MRI

    International Nuclear Information System (INIS)

    Takizawa, Shunya; Haida, Munetaka; Ohsuga, Hitoshi; Takagi, Shigeharu; Shinohara, Yukito

    1988-01-01

    A 49-year-old man presented with a 30-year history of oral and genital aphthous ulcers and joint pain. One day before his admission he developed double vision and weakness in the right extremities. Neurological examination revealed right 5th nerve palsy, left 6th to 18th nerve palsy, left Horner's sign, and motor and sensory impairment in the right upper and lower extremities. X-ray CT showed diffuse, weak, low-density areas in the brainstem. T1 weighted images showed low signals in the left side of the mid-pons, the left tegmentum and the right basis of the upper pons, and the left tegmentum of the midbrain. T2 weighted images showed high signals in the whole pons and the left side of the midbrain. MRI allowed the differentiation of reversible lesions, such as brain edema, and irreversible lesions, such as necrosis and demyelination of the tissue. (Namekawa, K.)

  1. MR measurement of normal brainstem cerebellum and corpus callosum on midsagittal section

    International Nuclear Information System (INIS)

    Kogame, Saeko; Sawa, S.; Inoue, Yuichi; Fukuda, Teruo; Tada, Takuji; Shakudo, Miyuki; Yahata, Kunifumi; Shimizu, Hiroshi; Onoyama, Yasuhito.

    1989-01-01

    The dimensions of the brainstem, cerebellum and corpus callosum were measured on magnetic resonance (MR) images with sagittal spin-echo sequence. Eighty-two normal adults (average 49.6 years old) were measured. The mesencephalic, pontine or cerebellar diamaters and lengths could be measured more accurately and reproducibly than medullary diameter and length. The anterio-posterior diameter of the pons and the cerebellum was 23.2±1.4 mm and 26.4±2.5 mm respectively. The length of the pons and the cerebellum was 27.8±2 mm and 45.8±3.5 mm respectively. We have observed focal thinning at the body of corpus callosum in 73%. This narrowing is almost unquestionably a normal variant. (author)

  2. Cavernous sinus thrombosis syndrome and brainstem involvement in patient with leptospirosis: Two rare complications of leptospirosis

    Directory of Open Access Journals (Sweden)

    Shahriyar Alian

    2014-01-01

    Full Text Available Leptospirosis is a bacterial disease that is caused by pathogenic spirochetes of the genus Leptospira. It can affect humans and animals. In humans, it can lead to a wide spectrum of symptoms. It is known as the most common zoonosis in the world. The typical presentation of the disease is an acute biphasic febrile illness with or without jaundice. Less common clinical manifestations may result from involvement of different human body systems. In many places, this disease may be under-diagnosed, especially when associated with neurological complications. Moreover, without treatment, leptospirosis can lead to organ damages, and even death. Neurological complications are uncommon and are reported in a few cases. Cavernous sinus thrombosis syndrome and brainstem involvement are rare complications of leptospirosis and are associated with a high mortality risk. To our knowledge, no such cases have been reported in the literature.

  3. Somatotopic arrangement and location of the corticospinal tract in the brainstem of the human brain.

    Science.gov (United States)

    Jang, Sung Ho

    2011-07-01

    The corticospinal tract (CST) is the most important motor pathway in the human brain. Detailed knowledge of CST somatotopy is important in terms of rehabilitative management and invasive procedures for patients with brain injuries. In this study, I conducted a review of nine previous studies of the somatotopical location and arrangement at the brainstem in the human brain. The results of this review indicated that the hand and leg somatotopies of the CST are arranged medio-laterally in the mid to lateral portion of the cerebral peduncle, ventromedial-dorsolaterally in the pontine basis, and medio-laterally in the medullary pyramid. However, few diffusion tensor imaging (DTI) studies have been conducted on this topic, and only nine have been reported: midbrain (2 studies), pons (4 studies), and medulla (1 study). Therefore, further DTI studies should be conducted in order to expand the literature on this topic. In particular, research on midbrain and medulla should be encouraged.

  4. A case of overlapping Bickerstaff's brainstem encephalitis and Guillain-Barré syndrome

    Institute of Scientific and Technical Information of China (English)

    WANG De-sheng; TANG Ying; WANG Ye

    2006-01-01

    Objective: There is no report on Bickerstaff's brainstem encephalitis (BBE) patients in China. We here report the first case of BBE in China. Methods: Clinical features, results of electromyography, electroencephalography (EEG), magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF) examination were studied to clarify the characteristics of this syndrome.Results: A 44-year-old man presented himself at our inpatient department with somnolence and dizziness as his initial symptoms.He developed multiple cranial nerves paralysis especially internal and external ophthalmoplegia, ataxia and tetraparesis within 1 week. His condition rapidly deteriorated, and he experienced coma. Electromyography showed indications of peripheral nerve dysfunction, electroencephalography revealed loss of basic rhythm, MRI demonstrated high-intensity abnormalities on T2-weighted images of medulla oblongata, and CSF albuminocytological dissociation was defined abnormally as high protein. Ten similar clinically; BBE and FS were proposed to be the variant of GBS.

  5. Survey of the Knowledge of Brainstem Death and Attitude Toward Organ Donation Among Relations of Neurosurgical Patients in Nigeria.

    Science.gov (United States)

    Rabiu, T B; Oshola, H A; Adebayo, B O

    2016-01-01

    Organ transplantation is a developing field in Nigeria, and availability of organs for donation would be a determining factor of the success of the transplant programs. Patients with brainstem death (BSD) are a major source of organs for transplantation. The level of knowledge of BSD as well as attitudes toward organ donation are very important determinants of people's willingness or otherwise to donate organs. We conducted a survey of relations of our in-service neurosurgical patients to assess their knowledge of brainstem death and attitude toward organ donation. To our knowledge, this is the first study of its kind among the growing Nigerian neurosurgery patient and patient-relations population. Convenience sampling of randomly selected relations of neurosurgical patients on admission using interviewer-administered questionnaires was performed. Demographic information and information about brainstem death, attitude toward brainstem death, knowledge of organ donation, and attitude toward organ donation were obtained. The study comprised 127 respondents with a mean age of 36 years (range, 19-72). The majority of the respondents (87, 62.4%) were Christians, 122 (96.1%) were Yorubas, and 66 (52.0%) were women. Eighty-five (66.9%) of the respondents had at least a secondary level of education, and 77 (60.6%) were of low socioeconomic status. Twenty-eight (22.2%) of the respondents had heard of brainstem death. Twenty-six (92.9%) of those who had heard of brainstem death believed that the brain could die long before life finally ceases. One hundred twenty-five (98.4%) of the respondents believed that death only occurs when both breathing and heartbeat stop, and 107 (83.6%) would agree with the physician on a diagnosis of brainstem death in the relation. Sixty-five (51.2%) would want such patients put on a ventilator, and, of these, 43 (66.2%) would want such patients on the ventilator in hope that he or she may recover. One hundred twelve (88.2%) of the relations were

  6. SU-F-T-392: Superior Brainstem and Cochlea Sparing with VMAT for Glioblastoma Multiforme

    Energy Technology Data Exchange (ETDEWEB)

    Briere, TM; McAleer, MF; Levy, LB; Yang, JN; Anderson, MD [Cancer Ctr., Houston, TX (United States)

    2016-06-15

    Purpose: Volumetric arc therapy (VMAT) can provide similar target coverage and normal tissue sparing as IMRT but with shorter treatment times. At our institution VMAT was adopted for the treatment glioblastoma multiforme (GBM) after a small number of test plans demonstrated its non-inferiority. In this study, we compare actual clinical treatment plans for a larger cohort of patients treated with either VMAT or IMRT. Methods: 90 GBM patients were included in this study, 45 treated with IMRT and 45 with VMAT. All planning target volumes (PTVs) were prescribed a dose of 50 Gy, with a simultaneous integrated boost to 60 Gy. Most IMRT plans used 5 non-coplanar beams, while most VMAT plans used 2 coplanar beams. Statistical analysis was performed using Fisher’s exact test or the Wilcoxon-Mann-Whitney rank sum test. Included in the analysis were patient and treatment characteristics as well as the doses to the target volumes and organs at risk. Results: Treatment times for the VMAT plans were reduced by 5 minutes compared with IMRT. The PTV coverage was similar, with at least 95% covered for all plans, while the median boost PTV dose differed by 0.1 Gy between the IMRT and VMAT cohorts. The doses to the brain, optic chiasm, optic nerves and eyes were not significantly different. The mean dose to the brainstem, however, was 9.4 Gy less with VMAT (p<0.001). The dose to the ipsilateral and contralateral cochleae were respectively 19.7 and 9.5 Gy less (p<0.001). Conclusion: Comparison of clinical treatment plans for separate IMRT and VMAT cohorts demonstrates that VMAT can save substantial treatment time while providing similar target coverage and superior sparing of the brainstem and cochleae. To our knowledge this is the first study to demonstrate this benefit of VMAT in the management of GBM.

  7. Involvement of ERK phosphorylation in brainstem neurons in modulation of swallowing reflex in rats

    Science.gov (United States)

    Tsujimura, Takanori; Kondo, Masahiro; Kitagawa, Junichi; Tsuboi, Yoshiyuki; Saito, Kimiko; Tohara, Haruka; Ueda, Koichiro; Sessle, Barry J; Iwata, Koichi

    2009-01-01

    In order to evaluate the neuronal mechanisms underlying functional abnormalities of swallowing in orofacial pain patients, this study investigated the effects of noxious orofacial stimulation on the swallowing reflex, phosphorylated extracellular signal-regulated kinase (pERK) and γ-aminobutyric acid (GABA) immunohistochemical features in brainstem neurons, and also analysed the effects of brainstem lesioning and of microinjection of GABA receptor agonist or antagonist into the nucleus tractus solitarii (NTS) on the swallowing reflex in anaesthetized rats. The swallowing reflex elicited by topical administration of distilled water to the pharyngolaryngeal region was inhibited after capsaicin injection into the facial (whisker pad) skin or lingual muscle. The capsaicin-induced inhibitory effect on the swallowing reflex was itself depressed after the intrathecal administration of MAPK kinase (MEK) inhibitor. No change in the capsaicin-induced inhibitory effect was observed after trigeminal spinal subnucleus caudalis lesioning, but the inhibitory effect was diminished by paratrigeminal nucleus (Pa5) lesioning. Many pERK-like immunoreactive neurons in the NTS showed GABA immunoreactivity. The local microinjection of the GABAA receptor agonist muscimol into the NTS produced a significant reduction in swallowing reflex, and the capsaicin-induced depression of the swallowing reflex was abolished by microinjection of the GABAA receptor antagonist bicuculline into the NTS. The present findings suggest that facial skin–NTS, lingual muscle–NTS and lingual muscle–Pa5–NTS pathways are involved in the modulation of swallowing reflex by facial and lingual pain, respectively, and that the activation of GABAergic NTS neurons is involved in the inhibition of the swallowing reflex following noxious stimulation of facial and intraoral structures. PMID:19124539

  8. Influence of sucrose ingestion on brainstem and hypothalamic intrinsic oscillations in lean and obese women.

    Science.gov (United States)

    Kilpatrick, Lisa A; Coveleskie, Kristen; Connolly, Lynn; Labus, Jennifer S; Ebrat, Bahar; Stains, Jean; Jiang, Zhiguo; Suyenobu, Brandall Y; Raybould, Helen E; Tillisch, Kirsten; Mayer, Emeran A

    2014-05-01

    The study of intrinsic fluctuations in the blood oxygen level-dependent signal of functional magnetic resonance imaging can provide insight into the effect of physiologic states on brain processes. In an effort to better understand the brain-gut communication induced by the absorption and metabolism of nutrients in healthy lean and obese individuals, we investigated whether ingestion of nutritive and non-nutritive sweetened beverages differentially engages the hypothalamus and brainstem vagal pathways in lean and obese women. In a 2-day, double-blind crossover study, 11 lean and 11 obese healthy women underwent functional magnetic resonance imaging scans after ingestion of 2 beverages of different sucrose content, but identical sweetness. During scans, subjects rested with eyes closed. Blood oxygen level-dependent fluctuations demonstrated significantly greater power in the highest frequency band (slow-3: 0.073-0.198 Hz) after ingestion of high-sucrose compared with low-sucrose beverages in the nucleus tractus solitarius for both groups. Obese women had greater connectivity between the right lateral hypothalamus and a reward-related brain region and weaker connectivity with homeostasis and gustatory-related brain regions than lean women. In a functional magnetic resonance imaging study, we observed sucrose-related changes in oscillatory dynamics of blood oxygen level-dependent fluctuations in brainstem and hypothalamus in lean and obese women. The observed frequency changes are consistent with a rapid vagally mediated mechanism due to nutrient absorption, rather than sweet taste receptor activation. These findings provide support for altered interaction between homeostatic and reward networks in obese individuals. Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.

  9. Involvement of ERK phosphorylation in brainstem neurons in modulation of swallowing reflex in rats.

    Science.gov (United States)

    Tsujimura, Takanori; Kondo, Masahiro; Kitagawa, Junichi; Tsuboi, Yoshiyuki; Saito, Kimiko; Tohara, Haruka; Ueda, Koichiro; Sessle, Barry J; Iwata, Koichi

    2009-02-15

    In order to evaluate the neuronal mechanisms underlying functional abnormalities of swallowing in orofacial pain patients, this study investigated the effects of noxious orofacial stimulation on the swallowing reflex, phosphorylated extracellular signal-regulated kinase (pERK) and gamma-aminobutyric acid (GABA) immunohistochemical features in brainstem neurons, and also analysed the effects of brainstem lesioning and of microinjection of GABA receptor agonist or antagonist into the nucleus tractus solitarii (NTS) on the swallowing reflex in anaesthetized rats. The swallowing reflex elicited by topical administration of distilled water to the pharyngolaryngeal region was inhibited after capsaicin injection into the facial (whisker pad) skin or lingual muscle. The capsaicin-induced inhibitory effect on the swallowing reflex was itself depressed after the intrathecal administration of MAPK kinase (MEK) inhibitor. No change in the capsaicin-induced inhibitory effect was observed after trigeminal spinal subnucleus caudalis lesioning, but the inhibitory effect was diminished by paratrigeminal nucleus (Pa5) lesioning. Many pERK-like immunoreactive neurons in the NTS showed GABA immunoreactivity. The local microinjection of the GABA(A) receptor agonist muscimol into the NTS produced a significant reduction in swallowing reflex, and the capsaicin-induced depression of the swallowing reflex was abolished by microinjection of the GABA(A) receptor antagonist bicuculline into the NTS. The present findings suggest that facial skin-NTS, lingual muscle-NTS and lingual muscle-Pa5-NTS pathways are involved in the modulation of swallowing reflex by facial and lingual pain, respectively, and that the activation of GABAergic NTS neurons is involved in the inhibition of the swallowing reflex following noxious stimulation of facial and intraoral structures.

  10. MRI and associated clinical characteristics of EV71-induced brainstem encephalitis in children with hand-foot-mouth disease

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Hongwu; Gan, Yungen [Shenzhen Children' s Hospital, Department of Radiology, Shenzhen (China); Wen, Feiqiu [Shenzhen Children' s Hospital, Department of Neurology, Shenzhen (China); Huang, Wenxian [Shenzhen Children' s Hospital, Department of Respiratory, Shenzhen (China)

    2012-06-15

    This study was conducted to investigate MRI and associated clinical characteristics of brainstem encephalitis induced by enterovirus 71 (EV71) in children with hand-foot-mouth disease (HFMD). We analyzed clinical and imaging data from 42 HFMD cases with EV71-induced brainstem encephalitis. All patients underwent plain and enhanced MRI cranial scans and were placed into one of two groups according to MRI enhancement results, an enhanced group or a nonenhanced group. Thirty-two cases were positive on MRI exam. The primary location of the lesion for brainstem encephalitis was the dorsal pons and medulla oblongata (32 cases), followed by the cerebellar dentate nucleus (8 cases), midbrain (5 cases), and thalamus (2 cases). Plain T1-weighted images showed isointense or hypointense signals, and T2-weighted images showed isointense and hyperintense signals. Enhanced MRI scans showed that 12 cases had slight to moderate enhancement; 4 of these were normal on plain scan. The time from MRI examination to disease onset was statistically different between the enhanced (n = 12) and nonenhanced (n = 21) groups with a mean of 7.67 days (SD = 1.07) vs 11.95 days (SD = 5.33), respectively. The most common neurological symptoms for brainstem encephalitis were myoclonus and tremor. The greater the area of affected brain, the more severe the clinical symptoms were. The locations of EV71-induced HFMD-associated brainstem encephalitis lesions are relatively specific. Enhanced MRI scans could also identify the lesions missed by early plain scans. MRI scans can provide important information for clinical evaluation and treatment. (orig.)

  11. Quantitative Magnetic Resonance Imaging of Brainstem Volumes, Plaques, and Surface Area in the Occipital Regions of Patients with Multiple Sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Alper, F.; Kantarci, M.; Altunkaynak, E.; Varoglu, A. O.; Karaman, A.; Oral, E.; Okur, A. [Ataturk Univ., Erzurum (Turkey). Depts. of Radiology, Histology, Neurology and Embryology, Psychiatry

    2006-07-15

    Purpose: To determine brainstem volumes, number of plaques, and surface areas in the occipital lobes of patients with relapsing remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS), and to investigate whether there is any correlation between brainstem volume and the number/surface areas of plaque in the occipital lobes. Material and Methods: Magnetic resonance imaging was obtained on 14 relapsing-remitting (RR) and 13 secondary progressive (SP) MS patients and 26 female control subjects. The Cavalieri method was used by modern design stereology to measure brainstem volume. The point-counting grid was used to evaluate sclerotic plaque surface areas in the occipital lobe. The number of plaques in the imaging section was calculated. Results: Brainstem volumes for RR and SP with multiple sclerosis and control subjects were 3647 mm{sup 3} , 3515 mm{sup 3} , and 4517 mm{sup 3} , respectively. Mean number of plaques in the right-left occipital lobe was found to be 2.7-3.4 in RR-MS and 5.2-2.8 in SP-MS. Mean plaque surface area in the right-left occipital lobe was determined to be 58.52-88.24 mm{sup 2} in RR MS and 124.3-64.82 mm{sup 2} in SP MS. Brainstem volumes were significantly reduced in both groups of patients with MS compared to controls ( P <0.01). Conclusion: Magnetic-resonance-estimated volume and surface area values in multiple sclerosis may facilitate our understanding of the clinical situation of patients and provide a simple index for evaluating therapeutic efficiency.

  12. MRI and associated clinical characteristics of EV71-induced brainstem encephalitis in children with hand-foot-mouth disease

    International Nuclear Information System (INIS)

    Zeng, Hongwu; Gan, Yungen; Wen, Feiqiu; Huang, Wenxian

    2012-01-01

    This study was conducted to investigate MRI and associated clinical characteristics of brainstem encephalitis induced by enterovirus 71 (EV71) in children with hand-foot-mouth disease (HFMD). We analyzed clinical and imaging data from 42 HFMD cases with EV71-induced brainstem encephalitis. All patients underwent plain and enhanced MRI cranial scans and were placed into one of two groups according to MRI enhancement results, an enhanced group or a nonenhanced group. Thirty-two cases were positive on MRI exam. The primary location of the lesion for brainstem encephalitis was the dorsal pons and medulla oblongata (32 cases), followed by the cerebellar dentate nucleus (8 cases), midbrain (5 cases), and thalamus (2 cases). Plain T1-weighted images showed isointense or hypointense signals, and T2-weighted images showed isointense and hyperintense signals. Enhanced MRI scans showed that 12 cases had slight to moderate enhancement; 4 of these were normal on plain scan. The time from MRI examination to disease onset was statistically different between the enhanced (n = 12) and nonenhanced (n = 21) groups with a mean of 7.67 days (SD = 1.07) vs 11.95 days (SD = 5.33), respectively. The most common neurological symptoms for brainstem encephalitis were myoclonus and tremor. The greater the area of affected brain, the more severe the clinical symptoms were. The locations of EV71-induced HFMD-associated brainstem encephalitis lesions are relatively specific. Enhanced MRI scans could also identify the lesions missed by early plain scans. MRI scans can provide important information for clinical evaluation and treatment. (orig.)

  13. Quantitative Magnetic Resonance Imaging of Brainstem Volumes, Plaques, and Surface Area in the Occipital Regions of Patients with Multiple Sclerosis

    International Nuclear Information System (INIS)

    Alper, F.; Kantarci, M.; Altunkaynak, E.; Varoglu, A. O.; Karaman, A.; Oral, E.; Okur, A.

    2006-01-01

    Purpose: To determine brainstem volumes, number of plaques, and surface areas in the occipital lobes of patients with relapsing remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS), and to investigate whether there is any correlation between brainstem volume and the number/surface areas of plaque in the occipital lobes. Material and Methods: Magnetic resonance imaging was obtained on 14 relapsing-remitting (RR) and 13 secondary progressive (SP) MS patients and 26 female control subjects. The Cavalieri method was used by modern design stereology to measure brainstem volume. The point-counting grid was used to evaluate sclerotic plaque surface areas in the occipital lobe. The number of plaques in the imaging section was calculated. Results: Brainstem volumes for RR and SP with multiple sclerosis and control subjects were 3647 mm 3 , 3515 mm 3 , and 4517 mm 3 , respectively. Mean number of plaques in the right-left occipital lobe was found to be 2.7-3.4 in RR-MS and 5.2-2.8 in SP-MS. Mean plaque surface area in the right-left occipital lobe was determined to be 58.52-88.24 mm 2 in RR MS and 124.3-64.82 mm 2 in SP MS. Brainstem volumes were significantly reduced in both groups of patients with MS compared to controls ( P <0.01). Conclusion: Magnetic-resonance-estimated volume and surface area values in multiple sclerosis may facilitate our understanding of the clinical situation of patients and provide a simple index for evaluating therapeutic efficiency

  14. Feasibility of creating a high-resolution 3D diffusion tensor imaging based atlas of the human brainstem: a case study at 11.7 T.

    Science.gov (United States)

    Aggarwal, Manisha; Zhang, Jiangyang; Pletnikova, Olga; Crain, Barbara; Troncoso, Juan; Mori, Susumu

    2013-07-01

    A three-dimensional stereotaxic atlas of the human brainstem based on high resolution ex vivo diffusion tensor imaging (DTI) is introduced. The atlas consists of high resolution (125-255 μm isotropic) three-dimensional DT images of the formalin-fixed brainstem acquired at 11.7 T. The DTI data revealed microscopic neuroanatomical details, allowing three-dimensional visualization and reconstruction of fiber pathways including the decussation of the pyramidal tract fibers, and interdigitating fascicles of the corticospinal and transverse pontine fibers. Additionally, strong gray-white matter contrasts in the apparent diffusion coefficient (ADC) maps enabled precise delineation of gray matter nuclei in the brainstem, including the cranial nerve and the inferior olivary nuclei. Comparison with myelin-stained histology shows that at the level of resolution achieved in this study, the structural details resolved with DTI contrasts in the brainstem were comparable to anatomical delineation obtained with histological sectioning. Major neural structures delineated from DTI contrasts in the brainstem are segmented and three-dimensionally reconstructed. Further, the ex vivo DTI data are nonlinearly mapped to a widely-used in vivo human brain atlas, to construct a high-resolution atlas of the brainstem in the Montreal Neurological Institute (MNI) stereotaxic coordinate space. The results demonstrate the feasibility of developing a 3D DTI based atlas for detailed characterization of brainstem neuroanatomy with high resolution and contrasts, which will be a useful resource for research and clinical applications. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Dual DNA binding property of ABA insensitive 3 like factors targeted to promoters responsive to ABA and auxin.

    Science.gov (United States)

    Nag, Ronita; Maity, Manas Kanti; Dasgupta, Maitrayee

    2005-11-01

    The ABA responsive ABI3 and the auxin responsive ARF family of transcription factors bind the CATGCATG (Sph) and TGTCTC core motifs in ABA and auxin response elements (ABRE and AuxRE), respectively. Several evidences indicate ABI3s to act downstream to auxin too. Because DNA binding domain of ABI3s shows significant overlap with ARFs we enquired whether auxin responsiveness through ABI3s could be mediated by their binding to canonical AuxREs. Investigations were undertaken through in vitro gel mobility shift assays (GMSA) using the DNA binding domain B3 of PvAlf (Phaseolus vulgaris ABI3 like factor) and upstream regions of auxin responsive gene GH3 (-267 to -141) and ABA responsive gene Em (-316 to -146) harboring AuxRE and ABRE, respectively. We demonstrate that B3 domain of PvAlf could bind AuxRE only when B3 was associated with its flanking domain B2 (B2B3). Such strict requirement of B2 domain was not observed with ABRE, where B3 could bind with or without being associated with B2. This dual specificity in DNA binding of ABI3s was also demonstrated with nuclear extracts of cultured cells of Arachis hypogea. Supershift analysis of ABRE and AuxRE bound nuclear proteins with antibodies raised against B2B3 domains of PvAlf revealed that ABI3 associated complexes were detectable in association with both cis elements. Competition GMSA confirmed the same complexes to bind ABRE and AuxRE. This dual specificity of ABI3 like factors in DNA binding targeted to natural promoters responsive to ABA and auxin suggests them to have a potential role in conferring crosstalk between these two phytohormones.

  16. The utility of preoperative diffusion tensor imaging in the surgical management of brainstem cavernous malformations.

    Science.gov (United States)

    Flores, Bruno C; Whittemore, Anthony R; Samson, Duke S; Barnett, Samuel L

    2015-03-01

    Resection of brainstem cavernous malformations (BSCMs) may reduce the risk of stepwise neurological deterioration secondary to hemorrhage, but the morbidity of surgery remains high. Diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) are neuroimaging techniques that may assist in the complex surgical planning necessary for these lesions. The authors evaluate the utility of preoperative DTI and DTT in the surgical management of BSCMs and their correlation with functional outcome. A retrospective review was conducted to identify patients who underwent resection of a BSCM between 2007 and 2012. All patients had preoperative DTI/DTT studies and a minimum of 6 months of clinical and radiographic follow-up. Five major fiber tracts were evaluated preoperatively using the DTI/DTT protocol: 1) corticospinal tract, 2) medial lemniscus and medial longitudinal fasciculus, 3) inferior cerebellar peduncle, 4) middle cerebellar peduncle, and 5) superior cerebellar peduncle. Scores were applied according to the degree of distortion seen, and the sum of scores was used for analysis. Functional outcomes were measured at hospital admission, discharge, and last clinic visit using modified Rankin Scale (mRS) scores. Eleven patients who underwent resection of a BSCM and preoperative DTI were identified. The mean age at presentation was 49 years, with a male-to-female ratio of 1.75:1. Cranial nerve deficit was the most common presenting symptom (81.8%), followed by cerebellar signs or gait/balance difficulties (54.5%) and hemibody anesthesia (27.2%). The majority of the lesions were located within the pons (54.5%). The mean diameter and estimated volume of lesions were 1.21 cm and 1.93 cm(3), respectively. Using DTI and DTT, 9 patients (82%) were found to have involvement of 2 or more major fiber tracts; the corticospinal tract and medial lemniscus/medial longitudinal fasciculus were the most commonly affected. In 2 patients with BSCMs without pial presentation, DTI

  17. Brainstem circuitry regulating phasic activation of trigeminal motoneurons during REM sleep.

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    Christelle Anaclet

    2010-01-01

    Full Text Available Rapid eye movement sleep (REMS is characterized by activation of the cortical and hippocampal electroencephalogram (EEG and atonia of non-respiratory muscles with superimposed phasic activity or twitching, particularly of cranial muscles such as those of the eye, tongue, face and jaw. While phasic activity is a characteristic feature of REMS, the neural substrates driving this activity remain unresolved. Here we investigated the neural circuits underlying masseter (jaw phasic activity during REMS. The trigeminal motor nucleus (Mo5, which controls masseter motor function, receives glutamatergic inputs mainly from the parvocellular reticular formation (PCRt, but also from the adjacent paramedian reticular area (PMnR. On the other hand, the Mo5 and PCRt do not receive direct input from the sublaterodorsal (SLD nucleus, a brainstem region critical for REMS atonia of postural muscles. We hypothesized that the PCRt-PMnR, but not the SLD, regulates masseter phasic activity during REMS.To test our hypothesis, we measured masseter electromyogram (EMG, neck muscle EMG, electrooculogram (EOG and EEG in rats with cell-body specific lesions of the SLD, PMnR, and PCRt. Bilateral lesions of the PMnR and rostral PCRt (rPCRt, but not the caudal PCRt or SLD, reduced and eliminated REMS phasic activity of the masseter, respectively. Lesions of the PMnR and rPCRt did not, however, alter the neck EMG or EOG. To determine if rPCRt neurons use glutamate to control masseter phasic movements, we selectively blocked glutamate release by rPCRt neurons using a Cre-lox mouse system. Genetic disruption of glutamate neurotransmission by rPCRt neurons blocked masseter phasic activity during REMS.These results indicate that (1 premotor glutamatergic neurons in the medullary rPCRt and PMnR are involved in generating phasic activity in the masseter muscles, but not phasic eye movements, during REMS; and (2 separate brainstem neural circuits control postural and cranial muscle

  18. Ankles back in randomized controlled trial (ABrCt): braces versus neuromuscular exercises for the secondary prevention of ankle sprains. Design of a randomised controlled trial.

    Science.gov (United States)

    Janssen, Kasper W; van Mechelen, Willem; Verhagen, Evert Alm

    2011-09-27

    Ankle sprains are the most common sports and physical activity related injury. There is extensive evidence that there is a twofold increased risk for injury recurrence for at least one year post injury. In up to 50% of all cases recurrences result in disability and lead to chronic pain or instability, requiring prolonged medical care. Therefore ankle sprain recurrence prevention in athletes is essential. This RCT evaluates the effect of the combined use of braces and neuromuscular training (e.g. proprioceptive training/sensorimotor training/balance training) against the individual use of either braces or neuromuscular training alone on ankle sprain recurrences, when applied to individual athletes after usual care. This study was designed as three way randomized controlled trial with one year follow-up. Healthy individuals between 12 and 70 years of age, who were actively participating in sports and who had sustained a lateral ankle sprain in the two months prior to inclusion, were eligible for inclusion. After subjects had finished ankle sprain treatment by means of usual care, they were randomised to any of the three study groups. Subjects in group 1 received an eight week neuromuscular training program, subjects in group 2 received a sports brace to be worn during all sports activities for the duration of one year, and group 3 received a combination of the neuromuscular training program and a sports brace to be worn during all sports activities for the duration of eight weeks. Outcomes were assessed at baseline and every month for 12 months therafter. The primary outcome measure was incidence of ankle sprain recurrences. Secondary outcome measures included the direct and indirect costs of recurrent injury, the severity of recurrent injury, and the residual complaints during and after the intervention. The ABrCt is the first randomized controlled trial to directly compare the secondary preventive effect of the combined use of braces and neuromuscular training

  19. Ankles back in randomized controlled trial (ABrCt: braces versus neuromuscular exercises for the secondary prevention of ankle sprains. Design of a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Verhagen Evert ALM

    2011-09-01

    Full Text Available Abstract Background Ankle sprains are the most common sports and physical activity related injury. There is extensive evidence that there is a twofold increased risk for injury recurrence for at least one year post injury. In up to 50% of all cases recurrences result in disability and lead to chronic pain or instability, requiring prolonged medical care. Therefore ankle sprain recurrence prevention in athletes is essential. This RCT evaluates the effect of the combined use of braces and neuromuscular training (e.g. proprioceptive training/sensorimotor training/balance training against the individual use of either braces or neuromuscular training alone on ankle sprain recurrences, when applied to individual athletes after usual care. Methods/Design This study was designed as three way randomized controlled trial with one year follow-up. Healthy individuals between 12 and 70 years of age, who were actively participating in sports and who had sustained a lateral ankle sprain in the two months prior to inclusion, were eligible for inclusion. After subjects had finished ankle sprain treatment by means of usual care, they were randomised to any of the three study groups. Subjects in group 1 received an eight week neuromuscular training program, subjects in group 2 received a sports brace to be worn during all sports activities for the duration of one year, and group 3 received a combination of the neuromuscular training program and a sports brace to be worn during all sports activities for the duration of eight weeks. Outcomes were assessed at baseline and every month for 12 months therafter. The primary outcome measure was incidence of ankle sprain recurrences. Secondary outcome measures included the direct and indirect costs of recurrent injury, the severity of recurrent injury, and the residual complaints during and after the intervention. Discussion The ABrCt is the first randomized controlled trial to directly compare the secondary preventive

  20. A comparative study of blood flow in the cerebellum and brainstem between Machado-Joseph disease and olivopontocerebellar atrophy

    International Nuclear Information System (INIS)

    Fukumitsu, Nobuyoshi; Suzuki, Masahiko; Ito Yasuhiko; Iguchi, Yasuyuki; Mori, Yutaka

    2002-01-01

    In recent years, the neurogenic and pathological differences between Machado-Joseph disease (MJD) and sporadic olivopontocerebellar atrophy (OPCA) have been clarified. We performed N-isopropyl-p-[I-123] iodoamphetamine (IMP) SPECT on 9 patients with MJD and 12 patients with OPCA. The blood flow of the cerebellum in the MJD group was significantly decreased than that of the control group (p<0.0001). That of OPCA group was significantly decreased than those of the control and MJD groups (p<0.0001, respectively). The blood flow of the brainstem in the MJD group was significantly decreased than that of the control group (p<0.001). That of OPCA group was significantly decreased than those of the control and MJD groups (p<0.0001, respectively). The blood flow of cerebellum and brainstem in the OPCA group were much decreased than those of MJD group. IMP distribution pattern in MJD patients obviously differed from that of OPCA patients. (author)

  1. Effects of cigarette smoke exposure on nicotinic acetylcholine receptor subunits {alpha}7 and {beta}2 in the sudden infant death syndrome (SIDS) brainstem

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    Machaalani, Rita, E-mail: rita.machaalani@sydney.edu.au [Department of Medicine, The University of Sydney, NSW 2006 (Australia); Bosch Institute, The University of Sydney, NSW 2006 (Australia); The Children' s Hospital at Westmead, NSW 2145 (Australia); Say, Meichien [Department of Medicine, The University of Sydney, NSW 2006 (Australia); Bosch Institute, The University of Sydney, NSW 2006 (Australia); Waters, Karen A. [Department of Medicine, The University of Sydney, NSW 2006 (Australia); Bosch Institute, The University of Sydney, NSW 2006 (Australia); The Children' s Hospital at Westmead, NSW 2145 (Australia)

    2011-12-15

    It is postulated that nicotine, as the main neurotoxic constituent of cigarette smoke, influences SIDS risk through effects on nicotinic acetylcholine receptors (nAChRs) in brainstem nuclei that control respiration and arousal. This study compared {alpha}7 and {beta}2 nAChR subunit expression in eight nuclei of the caudal and rostral medulla and seven nuclei of the pons between SIDS (n = 46) and non-SIDS infants (n = 14). Evaluation for associations with known SIDS risk factors included comparison according to whether infants had a history of exposure to cigarette smoke in the home, and stratification for sleep position and gender. Compared to non-SIDS infants, SIDS infants had significantly decreased {alpha}7 in the caudal nucleus of the solitary tract (cNTS), gracile and cuneate nuclei, with decreased {beta}2 in the cNTS and increased {beta}2 in the facial. When considering only the SIDS cohort: 1-cigarette smoke exposure was associated with increased {alpha}7 in the vestibular nucleus and increased {beta}2 in the rostral dorsal motor nucleus of the vagus, rNTS and Cuneate, 2-there was a gender interaction for {alpha}7 in the gracile and cuneate, and {beta}2 in the cNTS and rostral arcuate nucleus, and 3-there was no effect of sleep position on {alpha}7, but prone sleep was associated with decreased {beta}2 in three nuclei of the pons. In conclusion, SIDS infants demonstrate differences in expression of {alpha}7 and {beta}2 nAChRs within brainstem nuclei that control respiration and arousal, which is independent on prior history of cigarette smoke exposure, especially for the NTS, with additional differences for smoke exposure ({beta}2), gender ({alpha}7 and {beta}2) and sleep position ({beta}2) evident. -- Highlights: Black-Right-Pointing-Pointer The 'normal' response to smoke exposure is decreased {alpha}7 and {beta}2 in certain nuclei. Black-Right-Pointing-Pointer SIDS infants have decreased {alpha}7 in cNTS, Grac and Cun. Black

  2. Effects of cigarette smoke exposure on nicotinic acetylcholine receptor subunits α7 and β2 in the sudden infant death syndrome (SIDS) brainstem

    International Nuclear Information System (INIS)

    Machaalani, Rita; Say, Meichien; Waters, Karen A.

    2011-01-01

    It is postulated that nicotine, as the main neurotoxic constituent of cigarette smoke, influences SIDS risk through effects on nicotinic acetylcholine receptors (nAChRs) in brainstem nuclei that control respiration and arousal. This study compared α7 and β2 nAChR subunit expression in eight nuclei of the caudal and rostral medulla and seven nuclei of the pons between SIDS (n = 46) and non-SIDS infants (n = 14). Evaluation for associations with known SIDS risk factors included comparison according to whether infants had a history of exposure to cigarette smoke in the home, and stratification for sleep position and gender. Compared to non-SIDS infants, SIDS infants had significantly decreased α7 in the caudal nucleus of the solitary tract (cNTS), gracile and cuneate nuclei, with decreased β2 in the cNTS and increased β2 in the facial. When considering only the SIDS cohort: 1—cigarette smoke exposure was associated with increased α7 in the vestibular nucleus and increased β2 in the rostral dorsal motor nucleus of the vagus, rNTS and Cuneate, 2—there was a gender interaction for α7 in the gracile and cuneate, and β2 in the cNTS and rostral arcuate nucleus, and 3—there was no effect of sleep position on α7, but prone sleep was associated with decreased β2 in three nuclei of the pons. In conclusion, SIDS infants demonstrate differences in expression of α7 and β2 nAChRs within brainstem nuclei that control respiration and arousal, which is independent on prior history of cigarette smoke exposure, especially for the NTS, with additional differences for smoke exposure (β2), gender (α7 and β2) and sleep position (β2) evident. -- Highlights: ► The ‘normal’ response to smoke exposure is decreased α7 and β2 in certain nuclei. ► SIDS infants have decreased α7 in cNTS, Grac and Cun. ► SIDS infants have decreased β2 in cNTS and increased β2 in facial. ► The NTS is more sensitive to both α7 and β2 regulation in SIDS. ► Smoke exposure

  3. Brainstem edema caused by traumatic carotid-cavernous fistula: A case report and review of the literature

    OpenAIRE

    YU, JINLU; GUO, YUNBAO; ZHAO, SHUJIE; XU, KAN

    2015-01-01

    Brainstem edema caused by traumatic carotid-cavernous fistula (TCCF) is rare, and there is little information available regarding its clinical characteristics. The present report describes the case of a 51-year-old man with TCCF, who presented with right exophthalmos and intracranial bruit for 1 week. One month prior to admission at hospital, he fractured the frontal and ethmoid sinuses. Digital subtraction angiography confirmed the diagnosis of TCCF, and magnetic resonance imaging (MRI) sugg...

  4. Brainstem projections of neurons located in various subdivisions of the dorsolateral hypothalamic area – an anterograde tract-tracing study

    OpenAIRE

    Rege Sugárka Papp; Rege Sugárka Papp; Miklos ePalkovits; Miklos ePalkovits

    2014-01-01

    The projections from the dorsolateral hypothalamic area (DLH) to the lower brainstem have been investigated by using biotinylated dextran amine (BDA), an anterograde tracer in rats. The DLH can be divided into 3 areas (dorsomedial hypothalamus, perifornical area, lateral hypothalamic area), and further subdivided into 8 subdivisions. After unilateral stereotaxic injections of BDA into individual DLH subdivisions, the correct sites of injections were controlled histologically, and the distribu...

  5. Brainstem projections of neurons located in various subdivisions of the dorsolateral hypothalamic area—an anterograde tract-tracing study

    OpenAIRE

    Papp, Rege S.; Palkovits, Miklós

    2014-01-01

    The projections from the dorsolateral hypothalamic area (DLH) to the lower brainstem have been investigated by using biotinylated dextran amine (BDA), an anterograde tracer in rats. The DLH can be divided into 3 areas (dorsomedial hypothalamus, perifornical area, lateral hypothalamic area), and further subdivided into 8 subdivisions. After unilateral stereotaxic injections of BDA into individual DLH subdivisions, the correct sites of injections were controlled histologically, and the distribu...

  6. Brainstem dose is associated with patient-reported acute fatigue in head and neck cancer radiation therapy.

    Science.gov (United States)

    Ferris, Matthew J; Zhong, Jim; Switchenko, Jeffrey M; Higgins, Kristin A; Cassidy, Richard J; McDonald, Mark W; Eaton, Bree R; Patel, Kirtesh R; Steuer, Conor E; Baddour, H Michael; Miller, Andrew H; Bruner, Deborah W; Xiao, Canhua; Beitler, Jonathan J

    2018-01-01

    Radiation (RT) dose to the central nervous system (CNS) has been implicated as a contributor to treatment-related fatigue in head and neck cancer (HNC) patients undergoing radiation therapy (RT). This study evaluates the association of RT dose to CNS structures with patient-reported (PRO) fatigue scores in a population of HNC patients. At pre-RT (baseline), 6th week of RT, and 1-month post-RT time points, Multidimensional Fatigue Inventory (MFI-20) scores were prospectively obtained from 124 patients undergoing definitive treatment for HNC. Medulla, pons, midbrain, total brainstem, cerebellum, posterior fossa, and pituitary dosimetry were evaluated using summary statistics and dose-volume histograms, and associations with MFI-20 scores were analyzed. Maximum dose (Dmax) to the brainstem and medulla was significantly associated with MFI-20 scores at 6th week of RT and 1-month post-RT time points, after controlling for baseline scores (p<0.05). Each 1Gy increase in medulla Dmax resulted in an increase in total MFI-20 score over baseline of 0.30 (p=0.026), and 0.25 (p=0.037), at the 6th week of RT and 1-month post-RT, respectively. Each 1Gy increase in brainstem Dmax resulted in an increase in total MFI-20 score over baseline of 0.30 (p=0.027), and 0.25 (p=0.037) at the 6th week of RT, 1-month post-RT, respectively. Statistically significant associations were not found between dosimetry for the other CNS structures and MFI-20 scores. In this analysis of PRO fatigue scores from a population of patients undergoing definitive RT for HNC, maximum dose to the brainstem and medulla was associated with a significantly increased risk of acute patient fatigue. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Induction of brain CYP2E1 by chronic ethanol treatment and related oxidative stress in hippocampus, cerebellum, and brainstem

    International Nuclear Information System (INIS)

    Zhong, Yanjun; Dong, Guicheng; Luo, Haiguang; Cao, Jie; Wang, Chang; Wu, Jianyuan; Feng, Yu-Qi; Yue, Jiang

    2012-01-01

    Ethanol is one of the most commonly abused substances, and oxidative stress is an important causative factor in ethanol-induced neurotoxicity. Cytochrome P450 2E1 (CYP2E1) is involved in ethanol metabolism in the brain. This study investigates the role of brain CYP2E1 in the susceptibility of certain brain regions to ethanol neurotoxicity. Male Wistar rats were intragastrically treated with ethanol (3.0 g/kg, 30 days). CYP2E1 protein, mRNA expression, and catalytic activity in various brain regions were respectively assessed by immunoblotting, quantitative quantum dot immunohistochemistry, real-time RT-PCR, and LC–MS. The generation of reactive oxygen species (ROS) was analyzed using a laser confocal scanning microscope. The hippocampus, cerebellum, and brainstem were selectively damaged after ethanol treatment, indicated by both lactate dehydrogenase (LDH) activity and histopathological analysis. Ethanol markedly increased the levels of CYP2E1 protein, mRNA expression, and activity in the hippocampus and cerebellum. CYP2E1 protein and activity were significantly increased by ethanol in the brainstem, with no change in mRNA expression. ROS levels induced by ethanol paralleled the enhanced CYP2E1 proteins in the hippocampus, granular layer and white matter of cerebellum as well as brainstem. Brain CYP2E1 activity was positively correlated with the damage to the hippocampus, cerebellum, and brainstem. These results suggest that the selective sensitivity of brain regions to ethanol neurodegeneration may be attributed to the regional and cellular-specific induction of CYP2E1 by ethanol. The inhibition of CYP2E1 levels may attenuate ethanol-induced oxidative stress via ROS generation.

  8. Estudio de la vía auditiva central por medio de las respuestas evocadas auditivas del tronco encefálico (ABR, en niños con retraso en el lenguaje

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    Manuel Gallardo

    2003-03-01

    Full Text Available Objetivo: Determinar la integridad funcional de la vía auditiva en el tronco encefálico a través de las respuestas evocadas auditivas del tronco encefálico (ABR en niños con retardo en el lenguaje sin patología en oído medio y sistema nervioso central y sin factores de riesgo de hipoacusia neonatal. Diseño: Estudio retrospectivo transversal. Lugar: Servicios de otorrinolaringología del Centro Médico Naval y del Hospital Central de la Fuerza Aérea del Perú. Material y Métodos: Se analizó el ABR realizado en los últimos diez años a niños con retardo en el lenguaje, que incluyó 48 niños, 28 varones y 20 mujeres, con edades entre 1 y 11 años. Se evaluó los tiempos de latencia y la morfología de las ondas I, II, III, IV y V del ABR. Resultados: Se encontró las latencias dentro de lo normal para cada edad. En 77% de los pacientes hubo distorsión morfológica y/o hipovoltaje de las ondas, más frecuentemente (58% en las ondas I y II, correspondientes al nervio auditivo y núcleos cocleares en el tronco encefálico. Conclusiones: Los resultados sugieren que existe trastorno en la sincronización neural de la vía auditiva en el VIII par y en el tronco encefálico en 77% de los pacientes evaluados, lo cual afectaría el procesamiento auditivo central.

  9. Progressive supranuclear palsy: neuronal and glial cytoskeletal pathology in the higher order processing autonomic nuclei of the lower brainstem.

    Science.gov (United States)

    Rüb, U; Del Tredici, K; Schultz, C; de Vos, R A I; Jansen Steur, E N H; Arai, K; Braak, H

    2002-02-01

    The medial and lateral parabrachial nuclei (MPB, LPB), the gigantocellular reticular nucleus (GI), the raphes magnus (RMG) and raphes obscurus nuclei (ROB), as well as the intermediate reticular zone (IRZ) represent pivotal subordinate brainstem centres, all of which control autonomic functions. In this study, we investigated the occurrence and severity of the neuronal and glial cytoskeletal pathology in these six brainstem nuclei from 17 individuals with clinically diagnosed and neuropathologically confirmed progressive supranuclear palsy (PSP). The association between the severity of the pathology and the duration of the disease was investigated by means of correlation analysis. The brainstem nuclei in all of the PSP cases were affected by the neuronal cytoskeletal pathology, with the IRZ and GI regularly showing severe involvement, the MPB, RMG, and ROB marked involvement, and the LPB mild involvement. In the six nuclear greys studied, glial cells undergo alterations of their cytoskeleton on an irregular basis, whereby diseased oligodendrocytes predominantly presented as coiled bodies and affected astrocytes as thorn-shaped astrocytes. In all six nuclei, the severity of the neuronal or glial cytoskeletal pathology showed no correlation with the duration of PSP. In view of their functional role, the neuronal pathology in the nuclei studied offers a possible explanation for the autonomic dysfunctions that eventually develop in the course of PSP.

  10. Correlation between gadolinium-diethylenetriaminepentaacetic acid contrast enhancement and thallium-201 chloride uptake in pediatric brainstem glioma.

    Science.gov (United States)

    Maria, B L; Drane, W B; Quisling, R J; Hoang, K B

    1997-09-01

    We previously showed that thallium-201 (201Tl) chloride is accumulated in over 75% of brain tumors, including brainstem gliomas. The imaging of 201Tl with single photon emission computed tomography (SPECT) may require an abnormal increase in permeability of tumor vessels to allow penetration of the blood-brain barrier. To test this hypothesis, we evaluated the correlation between gadolinium enhancement and the degree of 201Tl uptake on SPECT and the contributions of either gadolinium enhancement or 201Tl uptake to the prognosis in children with brainstem gliomas. Forty-two sets of paired SPECT scans and magnetic resonance imaging (MRI) scans were obtained longitudinally in 13 cases. Altogether, 31 of 42 pairs (74%) of scans showed concordance between the presence of gadolinium enhancement and 201Tl uptake. There were no cases that demonstrated 201Tl uptake but lacked gadolinium enhancement. The results indicate that 201Tl SPECT is of value primarily when brainstem tumors have vessels that are demonstrably permeable to gadolinium, prior to or as a result of radiotherapy.

  11. Heart rate variability and QT dispersion study in brain death patients and comatose patients with normal brainstem function

    International Nuclear Information System (INIS)

    Vakilian, A.R.; Iranmanesh, F.; Nadimi, A.E.; Kahnali, J.A.

    2011-01-01

    To compare heart rate variability (HRV) and QT dispersion in comatose patients with normal brainstem function and with brain death. Fourteen brain death patients with clinical signs of imminent brain death and 15 comatose patients were examined by neurologist in intensive care unit. HRV, RR interval and QT dispersion on ECG were assessed for 24 hours in both groups. Independent t-test and chi-square test were used for statistical analysis to determine significance which was set at p < 0.05. According to Holter findings, mean of standard deviation of RR-interval in the comatose and brain death groups was 48.33 and 35 respectively (p = 0.045). Mean of covariance coefficient of RR-interval was 0.065 in the comatose group and 0.043 in the brain deaths (p = 0.006). QT dispersion was not significant difference in two groups. HRV and RR-interval analysis appeared as an early finding for the diagnosis of brainstem death in comparison to comatose patients with normal brainstem function. QT dispersion had not significant in this regard. (author)

  12. Difficult diagnosis of brainstem glioblastoma multiforme in a woman: a case report and review of the literature

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    Lakhan Shaheen E

    2009-10-01

    Full Text Available Abstract Introduction Brainstem gliomas are rare in adults. They most commonly occur in the pons and are most likely to be high-grade lesions. The diagnosis of a high-grade brainstem glioma is usually reached due to the presentation of rapidly progressing brainstem, cranial nerve and cerebellar symptoms. These symptoms do, however, overlap with a variety of other central nervous system disorders. Magnetic resonance imaging is the radiographic modality of choice, but can still be misleading. Case presentation A 48-year-old Caucasian woman presented with headache and vomiting followed by cerebellar signs and confusion. Magnetic resonance imaging findings were suggestive of a demyelinating process, but the patient failed to respond to therapy. Her condition rapidly progressed and she died. At autopsy, a high-grade invasive pontine tumor was identified. Histological evaluation revealed glioblastoma multiforme. Conclusion While pontine gliomas are rare in adults, those that do occur tend to be high-grade and rapidly progressive. Progression of symptoms from non-specific findings of headache and vomiting to rapid neurological deterioration, as occurred in our patient, is common in glioblastoma multiforme. While radiographic findings are often suggestive of the underlying pathology, this case represents the possibility of glioblastoma multiforme presenting as a deceptively benign appearing lesion.

  13. Proposed Toxic and Hypoxic Impairment of a Brainstem Locus in Autism

    Directory of Open Access Journals (Sweden)

    Woody R. McGinnis

    2013-12-01

    Full Text Available Electrophysiological findings implicate site-specific impairment of the nucleus tractus solitarius (NTS in autism. This invites hypothetical consideration of a large role for this small brainstem structure as the basis for seemingly disjointed behavioral and somatic features of autism. The NTS is the brain’s point of entry for visceral afference, its relay for vagal reflexes, and its integration center for autonomic control of circulatory, immunological, gastrointestinal, and laryngeal function. The NTS facilitates normal cerebrovascular perfusion, and is the seminal point for an ascending noradrenergic system that modulates many complex behaviors. Microvascular configuration predisposes the NTS to focal hypoxia. A subregion—the “pNTS”—permits exposure to all blood-borne neurotoxins, including those that do not readily transit the blood-brain barrier. Impairment of acetylcholinesterase (mercury and cadmium cations, nitrates/nitrites, organophosphates, monosodium glutamate, competition for hemoglobin (carbon monoxide, nitrates/nitrites, and higher blood viscosity (net systemic oxidative stress are suggested to potentiate microcirculatory insufficiency of the NTS, and thus autism.

  14. Recurrent Guillain-Barré syndrome, Miller Fisher syndrome and Bickerstaff brainstem encephalitis.

    Science.gov (United States)

    Ishii, Junko; Yuki, Nobuhiro; Kawamoto, Michi; Yoshimura, Hajime; Kusunoki, Susumu; Kohara, Nobuo

    2016-05-15

    Guillain-Barré syndrome (GBS), Miller Fisher syndrome (MFS), and Bickerstaff brainstem encephalitis (BBE) are usually monophasic, but some patients experience recurrences after long asymptomatic intervals. We aimed to investigate clinical features of recurrent GBS, MFS, and BBE at a single hospital. Records from 97 consecutive patients with GBS, MFS or BBE who were admitted to a tertiary hospital between 2001 and 2013 were reviewed. Clinical and laboratory features of patients with recurrent GBS, MFS, or BBE were investigated. Patients included 55 (32 males) with GBS, 34 (22 males) with MFS, and 8 (6 males) with BBE. Recurrent cases occurred in 2 (4%) of the 55 patients with GBS, 4 (12%) of the 34 patients with MFS, and 2 (25%) of the 8 patients with BBE. Patients with recurrent MFS had a tendency to be younger at the first episode than patients with non-recurrent MFS (median, 22 versus 37years old). Symptoms and signs were less severe during relapses than during the initial episode in recurrent patients. Recurrences occurred more frequently in patients with MFS or BBE compared with those with GBS. Patients with recurrent MFS might be younger than those with non-recurrent MFS. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Postmortem diffusion MRI of the human brainstem and thalamus for deep brain stimulator electrode localization

    Science.gov (United States)

    Calabrese, Evan; Hickey, Patrick; Hulette, Christine; Zhang, Jingxian; Parente, Beth; Lad, Shivanand P.; Johnson, G. Allan

    2015-01-01

    Deep brain stimulation (DBS) is an established surgical therapy for medically refractory tremor disorders including essential tremor (ET) and is currently under investigation for use in a variety of other neurologic and psychiatric disorders. There is growing evidence that the anti-tremor effects of DBS for ET are directly related to modulation of the dentatorubrothalamic tract (DRT), a white matter pathway that connects the cerebellum, red nucleus, and ventral intermediate nucleus of the thalamus. Emerging white matter targets for DBS, like the DRT, will require improved 3D reference maps of deep brain anatomy and structural connectivity for accurate electrode targeting. High-resolution diffusion MRI of postmortem brain specimens can provide detailed volumetric images of important deep brain nuclei and 3D reconstructions of white matter pathways with probabilistic tractography techniques. We present a high spatial and angular resolution diffusion MRI template of the postmortem human brainstem and thalamus with 3D reconstructions of the nuclei and white matter tracts involved in ET circuitry. We demonstrate accurate registration of these data to in vivo, clinical images from patients receiving DBS therapy, and correlate electrode proximity to tractography of the DRT with improvement of ET symptoms. PMID:26043869

  16. Large-scale synchronized activity in the embryonic brainstem and spinal cord

    Directory of Open Access Journals (Sweden)

    Yoko eMomose-Sato

    2013-04-01

    Full Text Available In the developing central nervous system, spontaneous activity appears well before the brain responds to external sensory inputs. One of the earliest activities is observed in the hindbrain and spinal cord, which is detected as rhythmic electrical discharges of cranial and spinal motoneurons or oscillations of Ca2+- and voltage-related optical signals. Shortly after the initial expression, the spontaneous activity appearing in the hindbrain and spinal cord exhibits a large-scale correlated wave that propagates over a wide region of the central nervous system, maximally extending to the lumbosacral cord and to the forebrain. In this review, we describe several aspects of this synchronized activity by focusing on the basic properties, development, origin, propagation pattern, pharmacological characteristics, and possible mechanisms underlying the generation of the activity. These profiles differ from those of the respiratory and locomotion pattern generators observed in the mature brainstem and spinal cord, suggesting that the wave is primordial activity that appears during a specific period of embryonic development and plays some important roles in the development of the central nervous system.

  17. Case of Joubert syndrome. CT findings of brainstem and review of literature

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Hisaharu; Nakazato, Akihiko; Ikota, Hiroko; Koide, Hiroyoshi (Saitama Medical School (Japan)); Yasaka, Atsushi; Nakada, Yoshitaka

    1983-01-01

    Joubert et al. first reported a familial syndrome which showed episodic tachypena, abnormal eye movement, mental and motor retardation. Since then eighteen cases have been reported in the world. In this paper, we reported a male baby with Joubert syndrome who was observed since the newborn period. He showed episodic tachypnea (respiratory rate over 100/min), apnea, severe mental and motor retardation, no normal eye movements, occipital meningocele, high arched palate and poor sucking. CT scan revealed vermian agenesis, hypoplasia and deformity of brainstem, enlarged fourth ventricle and cisterna magna. EEG showed episodic discharges. Laboratory test investigations including amino acids, lactate, pyruvate, ammonia, chromosomal analysis, IVP and renogram showed no abnormal findings. He showed poor development and at eleventh month of age he died at home because of respiratory arrest. Similar syndromes were reported by Koya et al., Dekaban, Gardner et al., D'Agostino et al. and Friede. They reported syndromes consisting of abnormal respiration, abnormal eye movements, mental and motor retardation, occipital meningocele, retinal degeneration and polycystic kidney. Some causative events may have occurred at 6 to 7 weeks of gestation affecting central nervous system as well as other organs.

  18. BRAINSTEM AUDITORY EVOKED POTENTIAL AS AN INDEX OF CNS DEMYELINATION IN GUILLAIN -BARRÉ SYNDROME (GBS

    Directory of Open Access Journals (Sweden)

    Smita Singh

    2016-01-01

    Full Text Available Background: Guillain-Barré Syndrome (GBS is an acute, frequently severe and fulminant polyradicular neuropathy that is autoimmune in nature. GBS manifest as rapidly evolving areflexic motor paralysis with or without sensory disturbances. It mainly involves peripheral nervous system and autonomic nervous system. There are rare evidences about the involvement of central nervous system (CNS in GBS. Aims: The main objective of the study was to assess the CNS involvement in GBS using the Brainstem Auditory Evoked Potential (BAEP. Methods & Material: The study was conducted in the clinical neurophysiology lab in the department of physiology, CSMMU Lucknow. Study group involved 26 subjects (n=26 having GBS and control group involved 30 normal subjects (n=30. BAEPS were recorded by Neuroperfect- EMG 2000 EMG/NCV/EPsytem. The data so obtained were subjected to analysis using Statistical Package for Social Sciences (SPSS Version 13.0. Results & Conclusions: There was significant increase in PIII & PV peak latencies and PI-PIII & PI-PV interpeak latencies in both left and right ear in the study group, which showed the CNS involvement in GBS which can be assessed using BAEP.

  19. A pilot study on predictors of brainstem raphe abnormality in patients with major depressive disorder.

    Science.gov (United States)

    Kostić, Milutin; Munjiza, Ana; Pesic, Danilo; Peljto, Amir; Novakovic, Ivana; Dobricic, Valerija; Tosevski, Dusica Lecic; Mijajlovic, Milija

    2017-02-01

    Hypo/anechogenicity of the brainstem raphe (BR) structures has been suggested as a possible transcranial parenchymal sonography (TCS) marker associated with depression. The aim of this study was to analyze possible association of the abnormal BR echogenicity in patients with major depression when compared to healthy controls, and to evaluate its clinical and genetic correlates. TCS was performed in 53 patients diagnosed as major depressive disorder (MDD) without psychotic symptoms and in 54 healthy matched controls. The TCS detected BR abnormalities were significantly more frequent in MDD patients (35 out of 53; 66%) in comparison to matched controls (5 out of 56; 9%). The prevalence of short allele (s) homozygocity in the length polymorphism of the promoter region of the serotonin transporter gene (5-HTTLPR) was significantly higher in MDD patients relative to those with normal BR echogenicity. A stepwise statistical discriminant analysis revealed statistically significant separation between MDD patients with and without BR abnormalities groups based on the four predictors combined: the Hamilton Anxiety Rating Scale item 5 ("difficulty in concentration, poor memory"), presence of social phobia, s allele homozygocity of the 5-HTTLPR polymorphism, and presence of generalized anxiety disorder. Cross-sectional design and heterogenous treatment of depressed patients. Reduced BR echogenicity in at least a subgroup of MDD patients may reflect a particular phenotype, characterized by more prevalent comorbid anxiety disorders, associated with particular genetic polymorphisms and neurotransmitter(s) deficits, most probably altered serotonergic mechanisms. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Expression of TASK-1 in brainstem and the occurrence of central sleep apnea in rats.

    Science.gov (United States)

    Wang, Jing; Zhang, Cheng; Li, Nan; Su, Li; Wang, Guangfa

    2008-03-20

    Recent studies revealed that unstable ventilation control is one of mechanisms underlying the occurrence of sleep apnea. Thus, we investigated whether TASK-1, an acid-sensitive potassium channel, plays a role in the occurrence of sleep apnea. First, the expression of TASK-1 transcriptions on brainstem was checked by in situ hybridization. Then, the correlation between the central apneic episodes and protein contents of TASK-1 measured by western blot was analyzed from 27 male rats. Results showed that TASK-1 mRNAs were widely distributed on the putative central chemoreceptors such as locus coeruleus, nucleus tractus solitarius and medullary raphe, etc. Both the total spontaneous apnea index (TSAI) and spontaneous apnea index in NREM sleep (NSAI) were positively correlated with TASK-1 protein contents (r=0.547 and 0.601, respectively, p<0.01). However, the post-sigh sleep apnea index (PAI) had no relationship with TASK-1 protein. Thus, we concluded that TASK-1 channels may function as central chemoreceptors that play a role in spontaneous sleep apneas in rats.