Dihydropyridine calcium channel antagonists disrupt migrating myoelectric complexes and counteract intestinal disorders associated with morphine withdrawal diarrhea

The electrogastrograms of a cohort of normal controls and a group of functional and postvagotomy dyspeptic patients, recorded under conditions of varying gastric distension applied via a gastric barostat, have been captured and stored on a portable PC. Retrospective quantitative and qualitative analysis of the waveforms have been carried out in the frequency domain. Gastric distension induced a reduction in gastric baseline frequency levels, which recovered after removal of the bolus. Controlled distension at a moderate level (240-480 ml) caused more symptoms in patients than in controls, but did not seem to affect the electrogastrograms. However, under conditions of high gastric distension (> 480 ml), there was a significant difference between the controls and patients predominant electrogastrographic frequencies (mean difference = 0.013 Hz; 95% CL = 0.001 Hz to 0.025 Hz; p = 0.014). We conclude that functional and postvagotomy dyspeptic patients have greater gastric electrical instability than controls, which seems to be more apparent under conditions of high gastric distension. The use of the Fourier transform and running spectral analysis method of analysis allowed this difference to be detected and measured.     

Orthostatic sympathetic derangement in subjects with fibromyalgia

OBJECTIVE: To assess the sympathetic-parasympathetic balance in individuals with fibromyalgia (FM), and its response to orthostatic stress, by power spectral analysis of heart rate variability. METHODS: We studied 19 women with FM and 19 age matched controls. A high resolution electrocardiogram was obtained in supine and standing postures after achieving a stable heart rate. Spectral analysis of R-R intervals was done by the fast Fourier transform algorithm. RESULTS: Analyses of the different frequency components revealed significant difference between the 2 groups in the low frequency (0.050-0.150 Hz) band, which reflects modulation of the sympathetic nervous system. Controls displayed an increased power spectral density upon standing (+0.081 +/- 0.217 Hz); individuals with FM had a discordant response (-0.057 +/- 0.097 Hz) (p = 0.018). CONCLUSION: In FM, there is a deranged sympathetic response to orthostatic stress. This abnormality may have implications regarding the pathogenesis of FM.     

Impaired heart rate variability in patients with symptomatic NYHA class II-III hypertrophic cardiomyopathy

Power spectral analysis of heart rate variability was performed to assess cardiac autonomic function using Holter monitoring in 19 hospitalized patients with symptomatic NYHA class II-III hypertrophic cardiomyopathy (sHCM), 20 ambulatory patients with asymptomatic NYHA class I hypertrophic cardiomyopathy (asHCM) and 20 normal control subjects. Power spectral analysis decomposed the heart rate variability into high-frequency power (HF: 0.15-0.40 Hz) and low-frequency power (LF: 0.04-0.15 Hz). HF was corrected by mean RR intervals (CCVHF). CCVHF values and LF/HF ratios were used as indices of vagal and sympathetic modulations, respectively. The sHCM group demonstrated no significant elevation in CCVHF during the nighttime as compared to the daytime, while asHCM and control groups showed significant CCVHF elevation during the nighttime (p < 0.05-0.01). The nighttime CCVHF, therefore, was significantly lower in the sHCM group than in the control or asHCM group (sHCM, 1.08 +/- 0.36%; control, 1.60 +/- 0.57%; asHCM 1.82 +/- 0.77%; sHCM vs. control or sHCM vs. asHCM, p < 0.01). All of these three groups showed significant reduction in LF/HF ratio during the nighttime as compared to the daytime (p < 0.01). However, the reduction in the sHCM group was not as great as that in the control group and there was a significant difference between the sHCM and control group (2.01 +/- 1.58 vs. 1.08 +/- 0.65, p < 0.05). Two patients in the sHCM group, who later died suddenly, demonstrated very low CCVHF throughout a 24-hour period (0.2-0.8%). Both vagal and sympathetic impairment with a predominance of vagal abnormalities is suggested in patients with symptomatic NYHA class II or III hypertrophic cardiomyopathy.     

Audiological correlates of speech understanding deficits in elderly listeners with mild-to-moderate hearing loss. II. Correlation analysis

OBJECTIVE: The study was conducted to determine the relationship between measures of auditory performance in elderly individuals. Specifically, its goal was to uncover a set of measures correlated with the set of measures of speech understanding under specific conditions of interference to gain a better understanding of decline of the "cocktail party effect" in aging. DESIGN: Audiological status and auditory performance of a group of elderly (60- to 81-yr-old) individuals were determined through a test battery. When present, the hearing loss of elderly subjects was symmetrical in the two ears and, at most, moderate. The battery included tests of speech intelligibility on the word and sentence levels, with and without the presence of interfering speech. In addition pure-tone and speech reception thresholds, perception of spectrally or temporally distorted speech and auditory resolution of frequency, time, and space were tested. Two tests received special consideration: the Speech Perception In Noise Test and the Modified Rhyme Reverberation Test. RESULTS: Results indicated that, despite the nearly normal hearing levels that characterized much of the subject group, auditory sensitivity measures showed persistent correlation to all other measures, with the exception of auditory resolution regarding frequency, time, and space. As a set, sensitivity measures accounted for more than 85% of the variance. When auditory sensitivity was controlled for, other factors underlying speech processing in the presence of interfering stimuli were uncovered, factors most likely related to the ability to perceptually segregate one speech signal from another. CONCLUSIONS: The findings suggest that, to determine the relationship between audiological/auditory test results of an elderly population, it is important to remove the effects of hearing loss through appropriate statistical methods.     

Antibody-directed enzyme prodrug therapy: pharmacokinetics and plasma levels of prodrug and drug in a phase I clinical trial

OBJECTIVE: The objective of the study was to determine the major factors that underlie auditory/audiological performance measures in an elderly population, with particular emphasis on finding those factors responsible for speech understanding under specific conditions of interference. DESIGN: Audiological status and auditory performance of a group of elderly (60- to 81-yr-old) and normal-hearing young (18- to 30-yr-old) individuals was determined through a test battery. When present, the hearing loss of elderly subjects was symmetrical in the two ears and, at most, moderate. The battery included tests of speech intelligibility on the word and sentence levels, with and without the presence of interfering speech. In addition to pure-tone and speech reception thresholds, perception of spectrally or temporally distorted speech as well as auditory resolution of frequency, time, and space were tested. Two tests received special consideration: the Speech Perception In Noise Test and the Modified Rhyme Reverberation Test. Taking the overall results as well as various subsets of the results, principal component analyses were conducted to identify major factors underlying auditory performance. RESULTS: The factors extracted by the principal component analyses present a portrayal of the auditory performance profile in which effects of interference, high-frequency hearing, and basic auditory function play a major role. Interference factors include general susceptibility to noise as well as segregation of concurrent speech sounds on the basis of temporal dissimilarities and spatial separation. Comparison of factors extracted from various subsets of tests indicate that factors underlying the decline of the "cocktail party effect" in the elderly are addressed mostly by tests specifically designed to assess speech understanding in spatially distributed babble or in a reverberant environment. CONCLUSIONS: Factor analysis of test measures obtained from a group of elderly individuals with normal hearing or mild-to-moderate hearing loss led to two main findings. First, it portrayed hearing loss as a component of different factors rather than as a factor on its own. Second, the independence of measures of speech understanding in babble or reverberation from other measures suggests that such tests should become an integral part of audiological test batteries designed to assess auditory functions in aging.     

Effect of chronic cadmium exposure on VEP and EEG spectral components

Pregnant swiss albino rats were divided to three groups as control (C), cadmium (Cd) and non-cadmium (NCd) groups. Control animals were received tap water while the rats of Cd group were received Cd as CdC12 in their drinking water during the experimental period. On the other hand, the NCd group was given Cd during pregnancy, but given tap water after birth. Twenty-two days after birth, fourteen rats (for each group) were taken from their mothers and continued to be treated with Cd (Cd group) or tap water (C and NCd groups) for an additional 38 days. After the experimental period, flash VEPs and EEGs of three groups were recorded and amplitude spectral analysis was computed by Transient Response-Frequency characteristics (TRFC) method. The mean amplitude (dB) of 1-3.5 and 14-20 Hz frequency bands for right response whereas 1-3.5, 4-7, 8-13 and 14-20 Hz frequency bands for left response of VEPs were decreased in Cd group compared with control group. On the other hand, significant differences were observed between Cd and control groups in all the frequency bands of EEGs except 6-8 Hz.     

The effect of the bacterial product, succinic acid, on neutrophil bactericidal activity

Patients with paroxysmal atrial fibrillation (AF) have greater overall P wave magnitude than control subjects, but the temporal localization of the increased energy is unknown. P wave spectral turbulence has not been investigated in such patients, and the optimum methodology for studying P wave signals has not been defined. This study, therefore, applied both spectrotemporal and spectral turbulence analyses to the signal-averaged P waves of patients with paroxysmal AF and to representative control subjects. Group A, 58 persons without cardiopulmonary disease (24 patients with paroxysmal AF, 34 control subjects), and group B, 57 with such disease (31 patients with paroxysmal AF, 26 control subjects), were studied. Spectral analysis was performed on a windowed 64-ms data segment that was advanced through the P wave in 2-ms steps. Spectral turbulence was measured from differentiated 24-ms data segments, by either cross-correlation between adjacent spectra, or differentiation of adjacent spectral coefficients over time (SV, spectral velocity). Patients had greater maximum P wave energy than control subjects, between 80-150 Hz for group A (means, 0.9 vs 0.7 microV2 x s), and 20-150 Hz for group B (means, 22.4 vs 16.3 microV2 x s). Spectral velocity was greater in patients with paroxysmal AF than in control subjects in both groups (group A: Peak SV, 11.6 vs 7.4 microV2 and group B: Peak SV, 12.0 vs 7.6 microV2). Increased energy and SV were reported in the central P wave. Spectrotemporal analysis suggested abnormal atrial activation in the central P wave associated with paroxysmal AF. A localized abnormality in atrial electrophysiology may cause the electrogenesis of the arrhythmia.     

The efficacy of ciprofloxacin and doxycycline against experimental tularaemia

A group of patients with balance complaints (n = 16) was compared with a group of normal subjects (n = 17) by means of posturography, subjective assessments of balance, anxiety and unsteadiness when standing on a force platform with eyes closed. Postural instability was induced by vibratory stimulation of the calf muscles (20, 40, 60, 80 and 100 Hz). As a control condition, the arm (biceps) was stimulated at similar frequencies. In order to control for arousal, blood pressure and heart beat were assessed. Furthermore, questionnaire responses on psychological measures were collected. Results showed clear differences between the groups in terms of imbalance and self-reports. However, the 2 groups displayed similar increases of imbalance during calf stimulation and no increase during arm stimulation. Patients generally rated less increase of unsteadiness when the calf was stimulated than did the controls. No differences in arousal were found between the groups or within conditions. Results are discussed in terms of the proposed desynchrony between symptoms and complaints.     

Speech competence in manic and schizophrenic psychoses: The association between clinically rated thought disorder and cohesion and reference performance.

Compared 20 thought-disordered (TD) manics and schizophrenics (mean age 31 yrs) to 20 manic and schizophrenic patients (mean age 31.25 yrs) without thought disorder (NTD) and to 10 normal Ss (mean age 30.9 yrs) normal on the rating scales of cohesion and reference performance in speech developed by S. R. Rochester and J. R. Martin (1979). TD manics and schizophrenics differed from NTD Ss and the normal group in their more frequent use of unclear references as well as in their less frequent use of effective cohesion and reference strategies. Speech elements of the TD Ss were classified into disordered and nondisordered segments, and the same natural language analysis was completed for each category of speech segments. Nondisordered speech segments of TD Ss were quite similar to the overall speech performance of NTD Ss and the normal group. There were no cohesion or reference performance differences between TD manics and TD schizophrenics in their disordered speech segments. Findings are interpreted as validation of the usefulness of the Rochester and Martin rating system for identifying aspects of speech performance that are related to clinically rated thought disorder. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Subgrouping children with familial phonologic disorders

Familial aggregation of speech and language disorders was examined as a basis of subgrouping children with phonologic disorders. Fifty-nine children with phonologic disorders were subgrouped according to whether or not other nuclear family members reported a history of speech/language disorders. Thirty-four subjects (58%) reported at least one other nuclear family member affected and 25 subjects (42%) reported no other nuclear family members affected. Groups were compared on measures of articulation, phonology, language, and oral motor skills to determine if the familial phonologic subgroup presented a unique profile of speech and language deficits. Significant group differences were not observed. However, children with positive nuclear family histories tended to perform more poorly than children without histories on all tasks, although not reaching significance. Although all parents were considered to have achieved normal adult articulation, parents of children with positive family histories also tended to perform more poorly than parents of children with negative histories. Results suggested that poorer oral motor coordination and productive phonology may distinguish individuals with familial phonologic disorders from individuals with phonologic disorders of unknown origin.     

Effects of noise and spectral resolution on vowel and consonant recognition: acoustic and electric hearing

Current multichannel cochlear implant devices provide high levels of speech performance in quiet. However, performance deteriorates rapidly with increasing levels of background noise. The goal of this study was to investigate whether the noise susceptibility of cochlear implant users is primarily due to the loss of fine spectral information. Recognition of vowels and consonants was measured as a function of signal-to-noise ratio in four normal-hearing listeners in conditions simulating cochlear implants with both CIS and SPEAK-like strategies. Six conditions were evaluated: 3-, 4-, 8-, and 16-band processors (CIS-like), a 6/20 band processor (SPEAK-like), and unprocessed speech. Recognition scores for vowels and consonants decreased as the S/N level worsened in all conditions, as expected. Phoneme recognition threshold (PRT) was defined as the S/N at which the recognition score fell to 50% of its level in quiet. The unprocessed speech had the best PRT, which worsened as the number of bands decreased. Recognition of vowels and consonants was further measured in three Nucleus-22 cochlear implant users using either their normal SPEAK speech processor or a custom processor with a four-channel CIS strategy. The best cochlear implant user showed similar performance with the CIS strategy in quiet and in noise to that of normal-hearing listeners when listening to correspondingly spectrally degraded speech. These findings suggest that the noise susceptibility of cochlear implant users is at least partly due to the loss of spectral resolution. Efforts to improve the effective number of spectral information channels should improve implant performance in noise.     

Detection of aortic porcine valve dysfunction by maximum entropy spectral analysis

A high-resolution method of spectral analysis, of the class generally called "maximum entropy method," was used in a study of aortic porcine valve closing sounds in 37 patients (ages 19 to 76). Spectra from 27 normal xenografts, implanted from 2 weeks to 61 months previously, were characterized by a dominant frequency peak, F1, at 89 +/- 15 Hz (mean +/- SD), with a lower amplitude peak, F2, at 154 +/- 25 Hz. Eight of nine patients with aortic porcine valve dysfunction were proved surgically to have leaflet degeneration or infection and had either F1 (139 +/- 54 Hz) and/or F2 (195 +/- 74 Hz) significantly higher than normal (p less than .001). In two patients with paravalvar leak but no leaflet abnormality, F1 and F2 were in the normal range. Estimation of F1 and F2 was highly reproducible and was unaffected by duration of implant up to 5 years. Spectral analysis of aortic porcine valve closing sounds by the maximum entropy method may be useful for detection of intrinsic xenograft dysfunction.     

The adaptive capacities of patients with panic disorders (a psychophysiological study)

Contingent-negative deviation (CND) and orientational reaction (OR) were studied in 9 women suffering from typical (according to DSM-III-R) panic disorders (PD) and 12 healthy females. CND recording was made after giving neutral (70 dB, 1000 Hz) and stress (120 dB, 2000 Hz) pairs of sounds. Patients with PD were divided in two groups depending upon CND amplitudes. The first group (4 patients) was distinguished from healthy individuals by high CND amplitude (which significantly decreased after reaction on stress sound), by delay of extinction of cutaneogalvanic reaction (CGR) and by higher electromyogram amplitude. The second group (5 patients with more severe course of PD) was characterized by low amplitudes of CND and electromyogram, by absence of changes in CND after stress sound, by delay of extinction of CGR and nonspecific response. Above-mentioned data were evidence of psychophysiological heterogeneity of typical PD. The results were interpreted from a position of adaptive abilities of patients with PD, using ineffective and immature psychophysiological strategies of overcoming stress.     

The varieties of speech to young children.

This article examines caregiver speech to young children. The authors obtained several measures of the speech used to children during early language development (14-30 months). For all measures, they found substantial variation across individuals and subgroups. Speech patterns vary with caregiver education, and the differences are maintained over time. While there are distinct levels of complexity for different caregivers, there is a common pattern of increase across age within the range that characterizes each educational group. Thus, caregiver speech exhibits both long-standing patterns of linguistic behavior and adjustment for the interlocutor. This information about the variability of speech by individual caregivers provides a framework for systematic study of the role of input in language acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enhancement of electrolaryngeal speech by adaptive filtering

Artificial larynges provide a means of verbal communication for people who have either lost or are otherwise unable to use their larynges. Although they enable adequate communication, the resulting speech has an unnatural quality and is significantly less intelligible than normal speech. One of the major problems with the widely used Transcutaneous Artificial Larynx (TAL) is the presence of a steady background noise caused by the leakage of acoustic energy from the TAL, its interface with the neck, and the surrounding neck tissue. The severity of the problem varies from speaker to speaker, partly depending upon the characteristics of the individual's neck tissue. The present study tests the hypothesis that TAL speech is enhanced in quality (as assessed through listener preference judgments) and intelligibility by removal of the inherent, directly radiated background signal. In particular, the focus is on the improvement of speech over the telephone or through some other electronic communication medium. A novel adaptive filtering architecture was designed and implemented to remove the background noise. Perceptual tests were conducted to assess speech, from two individuals with a laryngectomy and two normal speakers using the Servox TAL, before and after processing by the adaptive filter. A spectral analysis of the adaptively filtered TAL speech revealed a significant reduction in the amount of background source radiation yet preserved the acoustic characteristics of the vocal output. Results from the perceptual tests indicate a clear preference for the processed speech. In general, there was no significant improvement or degradation in intelligibility. However, the processing did improve the intelligibility of word-initial non-nasal consonants.     

Quantitation and kinetic properties of hepatic microsomal and recombinant flavin-containing monooxygenases 3 and 5 from humans

For many profoundly hearing-impaired listeners (hearing loss > 90 dB HL) speechreading is the most important means of communication; amplified speech may provide, at best, additional information to speechreading. In order to improve audiovisual communication, three speech pattern elements comprising voice-fundamental frequency (f0), the first formant (F1), and the first and the second formant (F1F2) were presented as supplements to speechreading. A fourth condition consisted of a natural speech supplement, a fifth of speechreading only. Twenty subjects were tested; all audiovisual speech scores were significantly higher than the purely visual scores. Audiovisual scores for amplified, natural speech were significantly higher than those for f0 and F1F2 coded speech. Scores for natural speech and for F1 coded speech were not significantly different. The relations between the increase in audiovisual speech scores over the visual scores and measures of difference limen for frequency (DLf) and gap detection were not clear. The most prominent correlations with the speech scores were found for the DLf at 125 Hz and for gap detection.     

Longitudinal analysis of physical activity and symptoms as predictors of change in functional limitations and disability in multiple sclerosis.

Objective: This longitudinal, observational study examined changes in physical activity and symptoms as correlates of changes in functional limitations and disability across a 6-month period among individuals with multiple sclerosis (MS). Method: Individuals with MS wore an accelerometer for a 7-day period and completed a battery of measures including the Godin Leisure-Time Exercise Questionnaire (Godin & Shephard, 1985), Symptom Inventory (Schwartz, Vollmer, & Lee, 1999), MS-Related Symptom Checklist (Gulick, 1989), and abbreviated Late-Life Function and Disability Inventory (McAuley, Konopack, Motl, Rosengren, & Morris, 2005) at baseline (n = 292) and 6-month follow-up (n = 276). The data were analyzed using panel analysis with latent variables in AMOS 16.0. Results: The standardized coefficients indicated that (a) change in physical activity was associated with residual change in function (β = .22), (b) change in symptoms was associated with residual changes in both function (β = –.29) and disability (γ = –.15), and (c) change in function was associated with residual change in disability (β = .20). Conclusion: Our findings indicate that change in physical activity is associated with change in disability through a pathway that is consistent with Nagi’s (1976) Disablement Model and its extension in individuals with MS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of angiotensin II, endothelin-1, and nitric oxide in HgCl2-induced acute renal failure

Although multichannel compression systems are quickly becoming integral components of programmable hearing aids, research results have not consistently demonstrated their benefit over conventional amplification. The present study examined two confounding factors that may have contributed to this inconsistency in results: alteration of temporal information and audibility of speech cues. Recognition of linearly amplified and multichannel-compressed speech was measured for listeners with mild-to-severe sensorineural hearing loss and for a control group of listeners with normal hearing. In addition to the standard speech signal, which provided both temporal and spectral information, the listener's ability to use temporal information in a multichannel compressed signal was directly tested using a signal-correlated noise (SCN) stimulus. This stimulus consisted of a time-varying speech envelope modulating a two-channel noise carrier. It preserved temporal cues but provided minimal spectral information. For each stimulus condition, short-term level measurements were used to determine the range of audible speech. Multichannel compression improved speech recognition under conditions where superior audibility was provided by the two-channel compression system over linear amplification. When audibility of both linearly amplified and multichannel-compressed speech was maximized, the multichannel compression had no significant effect on speech recognition score for speech containing both temporal and spectral cues. However, results for the SCN stimuli show that more extreme amounts of multichannel compression can reduce use of temporal information.     

Speech enhancement based on a sinusoidal model

Sinusoidal modeling is a new procedure for representing the speech signal. In this approach, the signal is divided into overlapping segments, the Fourier transform computed for each segment, and a set of desired spectral peaks is identified. The speech is then resynthesized using sinusoids that have the frequency, amplitude, and phase of the selected peaks, with the remaining spectral information being discarded. Using a limited number of sinusoids to reproduce speech in a background of multi-talker speech babble results in a speech signal that has an improved signal-to-noise ratio and enhanced spectral contrast. The more intense spectral components, assumed to be primarily the desired speech, are reproduced, whereas the less intense components, assumed to be primarily background noise, are not. To test the effectiveness of this processing approach as a noise suppression technique, both consonant recognition and perceived speech intelligibility were determined in quiet and in noise for a group of subjects with normal hearing as the number of sinusoids used to represent isolated speech tokens was varied. The results show that reducing the number of sinusoids used to represent the speech causes reduced consonant recognition and perceived intelligibility both in quiet and in noise, and suggests that similar results would be expected for listeners with hearing impairments.