Selective and nonselective cyclooxygenase-2 inhibitors and experimental fracture-healing. Reversibility of effects after short-term treatment.

BACKGROUND: Cyclooxygenase-2-specific anti-inflammatory drugs (coxibs) and nonspecific nonsteroidal anti-inflammatory drugs have been shown to inhibit experimental fracture-healing. The present study tested the hypothesis that these effects are reversible after short-term treatment. METHODS: With use of a standard model of fracture-healing, identical ED50 dosages of either a nonsteroidal anti-inflammatory drug (ketorolac), a coxib (valdecoxib), or vehicle (control) were orally administered to rats for either seven or twenty-one days and fracture-healing was assessed with biomechanical, histological, and biochemical analyses. RESULTS: When healing was assessed at twenty-one days, the seven-day treatment produced only a trend for a higher rate of nonunion in valdecoxib and ketorolac-treated animals as compared with controls. No differences were observed at thirty-five days. The twenty-one-day treatment produced significantly more nonunions in valdecoxib-treated animals as compared with either ketorolac-treated or control animals (p < 0.05), but these differences disappeared by thirty-five days. The dose-specific inhibition of these drugs on prostaglandin E2 levels and the reversibility of the effects after drug withdrawal were assessed in fracture calluses and showed that ketorolac treatment led to twofold to threefold lower levels of prostaglandin E2 than did valdecoxib. Withdrawal of either drug after six days led to a twofold rebound in these levels by fourteen days. Histological analysis showed delayed remodeling of calcified cartilage and reduced bone formation in association with valdecoxib treatment. CONCLUSIONS: Cyclooxygenase-2-specific drugs inhibit fracture-healing more than nonspecific nonsteroidal anti-inflammatory drugs, and the magnitude of the effect is related to the duration of treatment. However, after the discontinuation of treatment, prostaglandin E2 levels are gradually restored and the regain of strength returns to levels similar to control.

Electroacoustic contingency management of the acoustic spectra of speech.

Three studies involving the manipulation of the acoustic spectrum of speech are described. An array of electronic equipment was set up which signaled the presence or absence of certain frequency characteristics of speech. Subjects (Ss) were given feedback for production of speech containing targeted frequencies. The studies demonstrated that acoustic spectrum is amenable to modification by electroacoustic contingency management. It was indicated that the modified spectra are predictable and related to the phonetic structure of the language. Also, it was demonstrated that a sequence of spectra could be modified.

Diphthong changes in style shifting from Southern English to Standard American English.

This study was undertaken to identify the acoustic correlates of the diphthongs /aI/ and /contains as a subset I/ in individuals who were trained to "style shift" between Standard American English (SAE) and Southern English (SE). The diphthongs were produced by four individuals from the coastal southern dialect region who were selected from among those who had successfully completed an accent-reduction program. Results showed that diphthongs used in SE were shorter and had less noticeable transitional elements than those in SAE. The difference was more apparent for /aI/ than /contains as a subset I/. There were no instances in which a diphthong was completely replaced by a vowel in SE. Findings indicate that acoustic analysis may be a useful tool in identifying dialectal elements, particularly for those individuals who are learning to style shift.

Consistency of fundamental frequency and perturbation in repeated phonations of sustained vowels, reading, and connected speech.

The purpose of this study was to determine consistency of the acoustic measurement of fundamental frequency (f0) and f0 perturbation using the Visi-Pitch. Samples of speech including a reading passage, vowels, and spontaneous speech were recorded for 12 normal young adults (6 men and 6 women). The results indicated that test-retest reliability was highest for the reading passage. The measurements of fundamental frequency for reading and spontaneous speech were very similar, but vowel production was, on average, higher in frequency than the other contexts. Test-retest measures of perturbation using the Visi-Pitch did not have a high correlation coefficient. Perturbation measures must be interpreted cautiously because of the influence of frequency.

The prevalence of stuttering in the hearing-impaired school age population.

The purpose of this study was to determine the prevalence of stuttering in the current hearing-impaired school age population. Backus (1938) and Harms and Malone (1939) found a low incidence of stuttering in the hearing-impaired population in surveys conducted almost 50 years ago. Those surveys asked for information only on speech disfluency and did not collect information on disfluency in manual communication. The present survey was sent to 150 regional, private, and state schools for the hearing impaired. Seventy-seven schools responded, representing a total of 9,930 students enrolled. Twelve hearing-impaired students were reported who stutter: 3 were reported to stutter in the oral mode only, 6 in manual communication only, and 3 in both modes. The results indicate that the prevalence of stuttering in the hearing-impaired population is 0.12% and that perceived manual disfluency is more prevalent than oral disfluency.

A community based high risk register for hearing loss.

The critical need to identify children with hearing loss and provide treatment at the earliest possible age has become increasingly apparent in recent years (Northern & Downs, 1978). Reduction of the auditory signal during the critical language-learning period can severely limit the child's potential for developing a complete, effective communication system. Identification and treatment of children having handicapping conditions at an early age has gained impetus through the Handicapped Children's Early Education Program (HCEEP) projects funded by the Bureau of Education for the Handicapped (BEH).