SPET Monitoring of Perfusion Changes in Auditory Cortex following Mono- and Multi-Frequency Stimuli

1996 ◽  
Vol 35 (04) ◽  
pp. 112-115 ◽  
Author(s):  
Gaetano Paludetti ◽  
Walter di Nardo ◽  
Maria Calcagni ◽  
Daniela di Giuda ◽  
Giovanni Almadori ◽  
...  
Keyword(s):  
Auditory Cortex ◽  
High Intensity ◽  
Pure Tone ◽  
Low Frequency ◽  
Reliable Information ◽  
Research Support ◽  
Acoustic Stimuli ◽  
Cortical Areas ◽  
Contralateral Cortex ◽  
The Relationship

Summary Aim: In order to assess the relationship between auditory cortex perfusion and the frequency of acoustic stimuli, twenty normally-hearing subjects underwent cerebral SPET. Methods: In 10 patients a multi-frequency stimulus (250-4000 Hz at 40 dB SL) was delivered, while 10 subjects were stimulated with a 500 Hz pure tone at 40 dB SL. The prestimulation SPET was subtracted from poststimulation study and auditory cortex activation was expressed as percent increments. Results: Contralateral cortex was the most active area with multi-frequency and monofrequency stimuli as well. A clear demonstration of a tonotopic distribution of acoustic stimuli in the auditory cortex was achieved. In addition, the accessory role played by homolateral acoustic areas was confirmed. Conclusion: The results of the present research support the hypothesis that brain SPET may be useful to obtain semiquantitative reliable information on low frequency auditory level in profoundly deaf patients. This may be achieved comparing the extension of the cortical areas activated by high-intensity multifrequency stimuli.

scholarly journals Vestibular Hearing and Speech Processing

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Seyede Faranak Emami ◽  
Akram Pourbakht ◽  
Kianoush Sheykholeslami ◽  
Mohammad Kamali ◽  
Fatholah Behnoud ◽  
...  
Keyword(s):  
Word Recognition ◽  
White Noise ◽  
Speech Processing ◽  
High Intensity ◽  
Healthy Subjects ◽  
Low Frequency ◽  
Vestibular Evoked Myogenic Potentials ◽  
Noisy Conditions ◽  
The Right ◽  
The Relationship

Vestibular hearing in human is evoked as a result of the auditory sensitivity of the saccule to low-frequency high-intensity tone. The objective was to investigate the relationship between vestibular hearing using cervical vestibular-evoked myogenic potentials (cVEMPs) and speech processing via word recognition scores in white noise (WRSs in wn). Intervention comprised of audiologic examinations, cVEMPs, and WRS in wn. All healthy subjects had detectable cVEMPs (safe vestibular hearing). WRSs in wn were obtained for them (66.9 ± 9.3% in the right ears and 67.5 ± 11.8% in the left ears). Dizzy patients in the affected ears, had the cVEMPs abnormalities (insecure vestibular hearing) and decreased the WRS in wn (51.4 ± 3.8% in the right ears and 52.2 ± 3.5% in the left ears). The comparison of the cVEMPs between the subjects revealed significant differences (P < 0.05). Therefore, the vestibular hearing can improve the speech processing in the competing noisy conditions.

scholarly journals Spectral and spatial tuning of onset and offset response functions in auditory cortical fields A1 and CL of rhesus macaques

2017 ◽  
Vol 117 (3) ◽  
pp. 966-986 ◽  
Author(s):  
Deepa L. Ramamurthy ◽  
Gregg H. Recanzone
Keyword(s):  
Auditory Cortex ◽  
Rhesus Macaques ◽  
Primary Auditory Cortex ◽  
Evoked Responses ◽  
Neural Responses ◽  
Complex Cells ◽  
Acoustic Stimuli ◽  
Spatial Tuning ◽  
Response Profiles ◽  
The Relationship

The mammalian auditory cortex is necessary for spectral and spatial processing of acoustic stimuli. Most physiological studies of single neurons in the auditory cortex have focused on the onset and sustained portions of evoked responses, but there have been far fewer studies on the relationship between onset and offset responses. In the current study, we compared spectral and spatial tuning of onset and offset responses of neurons in primary auditory cortex (A1) and the caudolateral (CL) belt area of awake macaque monkeys. Several different metrics were used to determine the relationship between onset and offset response profiles in both frequency and space domains. In the frequency domain, a substantial proportion of neurons in A1 and CL displayed highly dissimilar best stimuli for onset- and offset-evoked responses, although even for these neurons, there was usually a large overlap in the range of frequencies that elicited onset, and offset responses and distributions of tuning overlap metrics were mostly unimodal. In the spatial domain, the vast majority of neurons displayed very similar best locations for onset- and offset-evoked responses, along with unimodal distributions of all tuning overlap metrics considered. Finally, for both spectral and spatial tuning, a slightly larger fraction of neurons in A1 displayed nonoverlapping onset and offset response profiles, relative to CL, which supports hierarchical differences in the processing of sounds in the two areas. However, these differences are small compared with differences in proportions of simple cells (low overlap) and complex cells (high overlap) in primary and secondary visual areas. NEW & NOTEWORTHY In the current study, we examine the relationship between the tuning of neural responses evoked by the onset and offset of acoustic stimuli in the primary auditory cortex, as well as a higher-order auditory area—the caudolateral belt field—in awake rhesus macaques. In these areas, the relationship between onset and offset response profiles in frequency and space domains formed a continuum, ranging from highly overlapping to highly nonoverlapping.

The Acceptable Noise Level and the Pure-Tone Audiogram

2017 ◽  
Vol 26 (1) ◽  
pp. 80-87 ◽  
Author(s):  
K. Jonas Brännström ◽  
Steen Østergaard Olsen
Keyword(s):  
Noise Level ◽  
Pure Tone ◽  
Hearing Aid ◽  
Low Frequency ◽  
Pure Tone Average ◽  
Pure Tone Audiogram ◽  
Hearing Thresholds ◽  
Acceptable Noise Level ◽  
The Relationship

PurposeThe vast majority of previous studies suggest that there is no relationship between the acceptable noise level (ANL) and pure-tone hearing thresholds reported as the average pure-tone hearing thresholds (pure-tone average). This study aims to explore (a) the relationship between hearing thresholds at individual frequencies and the ANL and (b) a measure of the slope of the audiogram and ANL.MethodSixty-three Danish adult hearing aid users participated. Assessments were pure-tone audiogram and 3 different versions of the ANL test made monaurally at 2 different sessions.ResultsThe findings show that low-frequency hearing thresholds and the slope of the audiogram are significantly related to all versions of the ANL.ConclusionIt is possible that previous studies have failed to discover a relationship between ANL and hearing thresholds due to the use of the broad 4-frequency pure-tone average. This has implications for our understanding of the ANL test.

Practical High Resolution Microscopy

1968 ◽  
Vol 26 ◽  
pp. 302-303
Author(s):  
P. A. Marsh ◽  
T. Mullens ◽  
D. Price
Keyword(s):  
High Resolution ◽  
Magnetic Fields ◽  
Low Frequency ◽  
Resolving Power ◽  
Careful Attention ◽  
Electron Microscopes ◽  
The Relationship ◽  
High Resolution Microscopy ◽  
New Facilities

It is possible to exceed the guaranteed resolution on most electron microscopes by careful attention to microscope parameters essential for high resolution work. While our experience is related to a Philips EM-200, we hope that some of these comments will apply to all electron microscopes.The first considerations are vibration and magnetic fields. These are usually measured at the pre-installation survey and must be within specifications. It has been our experience, however, that these factors can be greatly influenced by the new facilities and therefore must be rechecked after the installation is completed. The relationship between the resolving power of an EM-200 and the maximum tolerable low frequency interference fields in milli-Oerstedt is 10 Å - 1.9, 8 Å - 1.4, 6 Å - 0.8.

scholarly journals Competition and convergence between auditory and cross-modal visual inputs to primary auditory cortical areas

2011 ◽  
Vol 105 (4) ◽  
pp. 1558-1573 ◽  
Author(s):  
Yu-Ting Mao ◽  
Tian-Miao Hua ◽  
Sarah L. Pallas
Keyword(s):  
Auditory Cortex ◽  
Multisensory Processing ◽  
Sensory Deprivation ◽  
Target Space ◽  
Target Cells ◽  
Auditory Input ◽  
Visual Neurons ◽  
Cortical Areas ◽  
Visual Inputs ◽  
Medial Geniculate

Sensory neocortex is capable of considerable plasticity after sensory deprivation or damage to input pathways, especially early in development. Although plasticity can often be restorative, sometimes novel, ectopic inputs invade the affected cortical area. Invading inputs from other sensory modalities may compromise the original function or even take over, imposing a new function and preventing recovery. Using ferrets whose retinal axons were rerouted into auditory thalamus at birth, we were able to examine the effect of varying the degree of ectopic, cross-modal input on reorganization of developing auditory cortex. In particular, we assayed whether the invading visual inputs and the existing auditory inputs competed for or shared postsynaptic targets and whether the convergence of input modalities would induce multisensory processing. We demonstrate that although the cross-modal inputs create new visual neurons in auditory cortex, some auditory processing remains. The degree of damage to auditory input to the medial geniculate nucleus was directly related to the proportion of visual neurons in auditory cortex, suggesting that the visual and residual auditory inputs compete for cortical territory. Visual neurons were not segregated from auditory neurons but shared target space even on individual target cells, substantially increasing the proportion of multisensory neurons. Thus spatial convergence of visual and auditory input modalities may be sufficient to expand multisensory representations. Together these findings argue that early, patterned visual activity does not drive segregation of visual and auditory afferents and suggest that auditory function might be compromised by converging visual inputs. These results indicate possible ways in which multisensory cortical areas may form during development and evolution. They also suggest that rehabilitative strategies designed to promote recovery of function after sensory deprivation or damage need to take into account that sensory cortex may become substantially more multisensory after alteration of its input during development.

scholarly journals POS1456-HPR THE SERUM IRON LEVEL MIGHT BE USEFUL IN DETERMINING THE SEVERITY OF MALNUTRITION IN PATIENTS WITH RHEUMATOID ARTHRITIS

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1012.2-1012
Author(s):  
Y. Matsumoto ◽  
Y. Sugioka ◽  
M. Tada ◽  
T. Okano ◽  
K. Mamoto ◽  
...  
Keyword(s):  
Grip Strength ◽  
Serum Iron ◽  
Roc Analysis ◽  
Severe Malnutrition ◽  
Inflammatory Condition ◽  
Research Support ◽  
Chugai Pharmaceutical ◽  
The Relationship ◽  
Nutritional Indicator

Background:The Global Leadership Initiative on Malnutrition (GLIM) criteria, the first international criteria for diagnosis of malnutrition, was released in 2018 [1]. Patients with rheumatoid arthritis (RA) are thought to be prone to malnutrition due to decreased food intake and increased muscle catabolism caused by chronic inflammation or pain. However, there has been no report to assess the nutritional status of RA patients in accordance with the GLIM criteria. In addition, commonly used blood nutrient indicators such as albumin might not be appropriate as nutritional indicators for RA because these values are affected by inflammation.Objectives:This study aims to examine the rates of malnutrition in RA patients according to GLIM criteria, and the relationship between blood nutrient indicators and the severity of malnutrition.Methods:In this study, we conducted a cross-sectional survey of 135 female RA patients in 2020. According to the GLIM criteria, patients were considered to be malnourished if patients had one of the following phenotypic: (1) low body mass index, (2) non-volitional weight loss, (3) reduced muscle mass, and one of the following etiologic: (1) reduced food intake or assimilation, (2) disease burden/inflammatory condition. Reduced muscle mass was evaluated by measuring calf circumference, and inflammatory condition was evaluated by Disease Activity Score (DAS) 28. In accordance with the GLIM criteria, the severity of malnutrition was judged as three levels: no problem, moderate, and severe malnutrition. Albumin, transthyretin, transferrin, retinol binding protein, zinc, iron, ceruloplasmin, and total cholesterol were assessed as blood nutrition indicators. Also grip strength was assessed. We compared each nutritional indicator among the three groups according to the severity of malnutrition using age-adjusted analysis of covariance, and examined the relationship between each nutritional indicator and the severity of malnutrition using receiver operating characteristic (ROC) analysis.Results:In RA patients, 20% were classified as severe malnutrition, and 40% were moderate or more. Serum iron levels were significantly lower in the severe malnutrition group compared to the no problem group (p = 0.001). In ROC analysis, serum iron, zinc, albumin, and grip strength (area under curve; AUC; 0.680, 0.696, 0.636, 0.790, respectively) were significant parameters for classification of moderate and severe malnutrition. Serum iron and grip strength (AUC for respective parameters were 0.741, 0.747) were significant parameters for classification of severe malnutrition.Conclusion:Evaluation based on the GLIM criteria showed that about 40% of RA patients were under moderate or severe malnutrition. It was suggested that serum iron and grip strength might be useful to predict the severity of malnutrition.References:[1]Cederholm T, Jensen GL, Correia MITD, Gonzalez MC, Fukushima R, Higashiguchi T, et al. GLIM criteria for the diagnosis of malnutrition – A consensus report from the global clinical nutrition community. Clinical Nutrition 2019; 38: 1-9.Acknowledgements:We thank to Tomoko Nakatsuka, and the Center for Drug & Food Clinical Evaluation, Osaka City University Hospital, for management and collection of the study data. We also thank to study participants.Disclosure of Interests:Yoshinari Matsumoto Grant/research support from: Yamada Research Grant, Yuko Sugioka: None declared, Masahiro Tada: None declared, Tadasi Okano Speakers bureau: AbbVie, Asahikasei, Astellas Pharma Inc, Ayumi Pharmaceutical, Bristol-Myers Squibb, Chugai Pharmaceutical, Daiich Sankyo, Eisai, Janssen, Lilly, Mitsubishi Tanabe Pharma Corporation, Novartis Pharma, Ono Pharmaceutical, Pfizer, Sanofi, Takeda Pharmaceutical, Teijin Pharma and UCB, Grant/research support from: AbbVie, Eisai, Mitsubishi Tanabe Pharma Corporation and Nipponkayaku, Kenji Mamoto: None declared, Kentaro Inui Speakers bureau: Daiichi Sankyo Co. Ltd., Mitsubishi Tanabe Pharma, Janssen Pharmaceutical K.K., Astellas Pharma Inc., Takeda Pharmaceutical Co. Ltd., Ono Pharmaceutical Co. Ltd., Abbvie GK, Pfizer Inc., Eisai Co., Ltd., Chugai Pharmaceutical Co., Ltd, Grant/research support from: anssen Pharmaceutical K.K., Astellas Pharma Inc., Sanofi K.K., Abbvie GK, Takeda Pharmaceutical Co. Ltd., QOL RD Co. Ltd., Mitsubishi Tanabe Pharma, Ono Pharmaceutical Co. Ltd., Eisai Co., Ltd., Daiki Habu: None declared, Tatsuya Koike Speakers bureau: AbbVie, Astellas Pharma Inc, Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Janssen, Lilly, Mitsubishi Tanabe Pharma Corporation, MSD, Ono Pharmaceutical, Pfizer, Roche, Takeda Pharmaceutical, Teijin Pharma, and UCB, Grant/research support from: AbbVie, Astellas Pharma Inc, Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Janssen, Lilly, Mitsubishi Tanabe Pharma Corporation, MSD, Ono Pharmaceutical, Pfizer, Roche, Takeda Pharmaceutical, Teijin Pharma, and UCB

scholarly journals 1304. Characterization of Tebipenem Pivoxil Hydrobromide Pharmacokinetics-Pharmacodynamics (PK-PD) in a Neutropenic Murine Acute Pyelonephritis (AP) Model

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S666-S666
Author(s):  
Brian D VanScoy ◽  
Steven Fikes ◽  
Christopher M Rubino ◽  
Sujata M Bhavnani ◽  
Nicole S Cotroneo ◽  
...  
Keyword(s):  
Acute Pyelonephritis ◽  
Free Drug ◽  
Research Support ◽  
Model Free ◽  
Drug Concentrations ◽  
Drug Plasma ◽  
Dose Ranging ◽  
Tebipenem Pivoxil ◽  
Tract Infections ◽  
The Relationship

Abstract Background Tebipenem pivoxil hydrobromide (tebipenem HBr), an orally (PO) bioavailable prodrug of tebipenem, is a carbapenem with broad-spectrum activity against Gram-positive and -negative bacteria that is being developed for the treatment of patients with complicated urinary tract infections, including AP. Data from a one-compartment in vitro infection model demonstrated that the ratio of free-drug plasma area under the curve (AUC) to MIC with adjustment for dosing interval (τ) (AUC:MIC ratio•1/τ) was the PK-PD index most associated with tebipenem HBr efficacy [VanScoy BD et al., IDWeek 2019, Poster 1565]. Studies were undertaken to characterize the magnitude of tebipenem HBr free-drug plasma AUC:MIC ratio•1/τ associated with efficacy for Enterobacteriaceae using a neutropenic murine AP model. Methods A single dose pharmacokinetic study was completed in neutropenic mice infected via intra-renal injection with 104 CFU/kidney of Escherichia coli NCTC 13441. Following PO administration of 4 tebipenem HBr doses (1, 15, 45 and 100 mg/kg), plasma samples were collected at 0.25, 0.5, 1, 2, 4, 6 and 8 hours post-treatment initiation and drug concentrations were determined using LC/MS/MS. Dose-ranging studies were completed using a panel of 7 Enterobacteriaceae isolates (tebipenem HBr MIC values of 0.015 to 0.5 mg/L). Mice were infected with 104 CFU/kidney via intra-renal injection. Two hours post-incubation, 8 total daily tebipenem HBr doses (0.3 to 135 mg/kg) were fractionated into regimens given every 8 hours. The relationship between change in log10 CFU/g from baseline at 24 hours and free-drug plasma AUC:MIC ratio•1/τ was fit using a Hill-type model. Free-drug plasma AUC:MIC ratio•1/τ values associated with net bacterial stasis and 1- and 2-log10 CFU/g reductions from baseline at 24 hours were determined. Results The relationship between change in log10 CFU/g from baseline at 24 hours and tebipenem HBr free-drug plasma AUC:MIC ratio•1/τ described the data well (r2 = 0.833). Free-drug plasma AUC:MIC ratio•1/τ values associated with net bacterial stasis and a 1-log10 CFU/g reduction from baseline were 26.2 and 54.1, respectively. A 2-log10 CFU/g reduction was not achieved. Relationship between change in log10 CFU/g from baseline at 24 hours and tebipenem HBr free-drug plasma AUC:MIC ratio•1/τ based on data for a panel of Enterobacteriaceae isolates evaluated in the dose-ranging studies conducted using a neutropenic murine acute pyelonephritis model Conclusion These data will be useful to support tebipenem HBr dose selection for clinical studies in patients with AP. Disclosures Brian D. VanScoy, B.S., Institute for Clinical Pharmacodynamics, Inc. (Employee)Spero Therapeutics (Grant/Research Support) Steven Fikes, BA, Institute for Clinical Pharmacodynamics, Inc. (Employee)Spero Therapeutics (Grant/Research Support) Christopher M. Rubino, PharMD, Institute for Clinical Pharmacodynamics, Inc. (Employee)Spero Therapeutics (Grant/Research Support) Sujata M. Bhavnani, PharMD, MS, FIDSA, Institute for Clinical Pharmacodynamics, Inc. (Employee)Spero Therapeutics (Grant/Research Support) Nicole S. Cotroneo, BS, Spero Therapeutics (Employee, Shareholder) Ian A. Critchley, PhD, Spero Therapeutics (Employee, Shareholder) Thomas R. Parr, PhD, Spero Therapeutics (Employee, Shareholder) Paul G. Ambrose, PharMD, FIDSA, Institute for Clinical Pharmacodynamics, Inc. (Employee)Spero Therapeutics (Grant/Research Support)

Comparing the Effects of Immersed Versus Land-Based High-Intensity Interval Cycling on Energy Intake, Appetite Sensations and Perceived Exertion Among Healthy Men

2021 ◽  
pp. 003151252110073
Author(s):  
Lore Metz ◽  
Laurie Isacco ◽  
Maud Miguet ◽  
Pauline Genin ◽  
David Thivel ◽  
...  
Keyword(s):  
Energy Intake ◽  
High Intensity ◽  
Perceived Exertion ◽  
Area Under The Curve ◽  
Macronutrient Intake ◽  
Healthy Men ◽  
High Intensity Interval ◽  
Interval Cycling ◽  
Desire To Eat ◽  
The Relationship

Immersed exercise has been shown to induce higher energy expenditure and no difference or increase in food intake compared with similar exercise on land. In this study, we compared the effects of acute high-intensity cycling performed on land versus when immersed on subsequent energy intake (EI), appetite sensations and perceived exertion (RPE) in healthy men. Ten participants in a postprandial condition completed three experimental visits in a randomized order: a control condition (CONT); a high-intensity interval cycling exercise performed on land (HIIE-L) and the same exercise while immersed in water (HIIE-A) with a similar targeted heart rate. We observed no difference in energy and macronutrient intake and in area under the curve (AUC) for appetite sensations between sessions. The RPE at the end of HIIE-L was negatively correlated with EI (r=–0.67; p < 0.05), AUC for hunger (r=–0.86, p < 0.01), desire to eat (r=–0.78, p < 0.05) and prospective food consumption (r=–0.86, p < 0.01). Conversely, the RPE at the end of HIIE-L was positively correlated with AUC for fullness (r = 0.76 , p < 0.05). No such correlations were observed for HIIE-A. The present study was the first to observe that immersion did not influence EI after HIIE cycling, but immersion blunted the relationship between session RPE and subsequent energy intake and appetite sensations relative to HIIE on land.

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