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This study assesses several electrocochleographic (ECoG) duration and amplitude measures in a clinically defined Meniere's group and compares the results with those from a normal hearing control group and a hearing loss group (cochlear). The summating potential (SP)/action potential (AP) amplitude ratio was the most efficient diagnostic measure, with 62% of the Meniere's group demonstrating abnormal ratios compared to 4% of the normal control group and 17% of the cochlear group. The SP changes were then studied from three angles: 1. Comparison of SP changes with glycerol test results; 2. Comparison of ECoG results before and after shunt surgery; and 3. Recording of SP's in guinea pig ears in which hydrops had been created by obliterating the endolymphatic duct. [ABSTRACT FROM AUTHOR]

Timely diagnosis of multiple sclerosis (MS) is a challenge due to factors such as prompt identification of symptoms and consequent delays in hospital visits and treatment initiation. In part to address this challenge, an expert scientific advisory panel of clinical nurse practitioners (CNPs) from different European nations was convened by Viatris on October 25, 2022, in Amsterdam, the Netherlands. This meeting was an interactive discussion to understand the role of clinical nurse practitioners in MS management. The objectives were to (1) understand the current delays in MS diagnosis from the perspective of expert CNPs; (2) determine the role of the CNP in MS management; and (3) identify the opportunities to improve accessibility, foster collaboration among stakeholders, and promote initiatives to educate people with MS. The recommendations of the panel underline the multidimensional role of CNPs in the management of MS at all stages. Health care stakeholders need to work together to achieve better access to treatment regimens and facilitate outcomes in the management of MS through shared decision-making and follow-ups. Further exploration of the role of CNPs in the management of MS, as well as recommendations for early diagnosis, will help both general practitioners and specialists better manage MS care., (© 2024 Consortium of Multiple Sclerosis Centers.)

Objectives: To assess the precision and accuracy of single-camera photogrammetry (SCP) and multicamera photogrammetry (MCP) compared with direct anthropometry (DA)., Materials and Methods: A total of 30 participants were recruited, and 17 soft tissue landmarks were identified and used to complete a total of 16 measurements. Using SCP and MCP, two three-dimensional (3D) images were acquired from each participant. All 3D measurements and direct measurements were measured twice by the same operator to assess intraexaminer repeatability. Intraclass coefficients (ICCs) were used to evaluate intraexaminer repeatability and interexaminer agreement of the methods. Nonparametric bootstrap analyses were used to compare the means of the measurements among the three methods., Results: All three methods showed excellent intraexaminer repeatability (ICCs > 0.90), except interpupillary distance (ICC = 0.86) measured by SCP. Both SCP and MCP showed excellent interexaminer agreement (ICCs > 0.90), except interpupillary distance (ICC = 0.79), left gonion-pogonion (ICC = 0.74), and columella-subnasale-labrale superior angle (ICC = 0.86) measured by SCP. Overall, there was good agreement between methods, except for columella-subnasale-labrale superior angle (ICC = 0.40) between SCP and MCP., Conclusions: Both SCP and MCP techniques were found to be reliable and valid options for 3D facial imaging. SCP produced slightly larger mean values for several measurements, but the differences were within a clinically acceptable range. Because of the larger margin of errors, measurements including the gonial area and subnasale should be assessed with caution., (© 0000 by The EH Angle Education and Research Foundation, Inc.)

The acquisition of m 7 G-cap-binding proteins is now recognized as a major variable driving the form and function of host RNAs. This manuscript compares the 5'-cap-RNA binding proteins that engage HIV-1 precursor RNAs, host mRNAs, small nuclear (sn)- and small nucleolar (sno) RNAs and sort into disparate RNA-fate pathways. Before completion of the transcription cycle, the transcription start site of nascent class II RNAs is appended to a non-templated guanosine that is methylated (m 7 G-cap) and bound by hetero-dimeric CBP80-CBP20 cap binding complex (CBC). The CBC is a nexus for the co-transcriptional processing of precursor RNAs to mRNAs and the snRNA and snoRNA of spliceosomal and ribosomal ribonucleoproteins (RNPs). Just as sn/sno-RNAs experience hyper-methylation of m 7 G-cap to trimethylguanosine (TMG)-cap, so do select HIV RNAs and an emerging cohort of mRNAs. TMG-cap is blocked from Watson:Crick base pairing and disqualified from participating in secondary structure. The HIV TMG-cap has been shown to license select viral transcripts for specialized cap-dependent translation initiation without eIF4E that is dependent upon CBP80/NCBP3. The exceptional activity of HIV precursor RNAs secures their access to maturation pathways of sn/snoRNAs, canonical and non-canonical host mRNAs in proper stoichiometry to execute the retroviral replication cycle.

Objective: Soluble toll-like receptor-2 (sTLR2) and soluble CD14 (sCD14) in saliva are defense proteins that bind specific microbe-associated molecular patterns. Since the oral flora changes with aging, the objective of this study is to determine and compare the concentration of sTLR2 and sCD14 in the saliva of healthy individuals in age groups from the first to the sixth decade of life., Methods: Unstimulated whole saliva was collected after obtaining informed consent. The concentration of sCD14 and sTLR-2 was measured by enzyme-linked immunosorbent assay. Statistical differences between the age groups were determined by analysis of variance. The relationship between the two markers in each age group was evaluated by Pearson's correlation coefficient and linear regression analyses., Results: The concentration of salivary sTLR2 was highest in the youngest, and that of the sCD14 was highest in the oldest age group. While the salivary sCD14 and the sTLR2 exhibited a moderate negative correlation in the youngest, the relationship between the two markers was inversed in the oldest age group., Conclusions and Clinical Relevance: The results of our exploratory study suggest a need to adjust for age-dependent changes in sCD14 and sTLR2 in healthy saliva while assessing the two proteins as biomarkers.

The diverse functions of RNA provide numerous opportunities for programming biological circuits. We describe a new strategy that uses ribozyme K28min to covalently tag a specific nucleobase within an RNA or DNA target strand to regulate and selectively inactivate those nucleic acids. K28min variants with appropriately reprogrammed internal guide sequences efficiently tagged multiple sites from an mRNA and from aptamer and ribozyme targets. Upon covalent modification by the corresponding K28min variant, an ATP-binding aptamer lost all affinity for ATP, and the fluorogenic Mango aptamer lost its ability to activate fluorescence of its dye ligand. Modifying a hammerhead ribozyme near the catalytic core led to loss of almost all of its substrate-cleaving activity, but modifying the same hammerhead ribozyme within a tertiary stabilizing element that reduces magnesium dependence only impaired substrate cleavage at low magnesium concentration. Thus, ribozyme-mediated covalent modification can be used both to selectively inactivate and to fine-tune the activities of targeted functional RNAs, analogous to the effects of post-translational modifications of proteins. Ribozyme-catalyzed covalent modification could therefore be developed to regulate nucleic acids components of synthetic and natural circuits.

Background: Breast magnetic resonance imaging (MRI) is becoming an often-utilized examination in the preoperative planning for breast cancer. However, it is not yet accepted as a routine examination for all breast cancer patients due to the lack of data regarding whether breast MRI has any effect on recurrence or survival., Methods: The charts of 76 patients referred by their surgeons for breast MRI during breast cancer workup were reviewed to determine if the breast MRI changed the preoperative clinical staging, the operative plan, or prompted additional testing., Results: Thirty-eight of 76 patients (50%) received follow-up imaging and 22/76 (29%) received additional biopsies. The breast MRI upstaged the cancer in 14/76 patients (18%). There was a change in the surgical plan in 19 of 76 (25%) patients, all of whom received more extensive surgery than previously planned., Conclusion: Breast MRI contributed significantly to the workup and management of breast cancer at our institution, suggesting a higher stage in 18% of the patients and changing the surgical plan in 25% of the patients.

Advances in digital signal processing, microelectronics, and power technology have produced devices that have contributed significantly to the quality of life and communication abilities of individuals with hearing impairment and tinnitus. Future technological developments will expand the benefits of current devices and offer new treatments for otologic disorders.

The Nucleus 24 Contour is a new cochlear implant that has recently undergone clinical trials in adults and children. The Contour uses the same electronics as the previous-generation Nucleus 24 (CI24M) but incorporates a downsized receiver-stimulator and a perimodiolar electrode array. The indications for use were expanded to include children as young as 12 months of age and children 24 months of age and older with severe to profound hearing loss who had open-set word recognition up to 30%. The Contour was successfully implanted in 256 children. The mean level of postoperative speech perception with the Contour was significantly better than the preoperative baseline with hearing aids on all measures. Children who had open-set speech perception in an audition-only condition before surgery demonstrated higher levels of postoperative performance with the Contour than children with no open-set speech perception before surgery.

Objective: To report early postimplantation speech recognition results in children who received Nucleus CI24M cochlear implants., Study Design: The study group consisted of 19 consecutively implanted children., Patients and Setting: Congenitally deaf children (20 months to 15 years old) were implanted with the Nucleus CI24M and followed-up at New York University Medical Center for a period of 3 to 12 months., Main Outcome Measures: Speech perception was evaluated preoperatively and postoperatively using the Early Speech Perception (ESP) test, the Glendonald Auditory Screening Procedure (GASP) word and sentence tests, Phonetically Balanced Kindergarten (PBK) monosyllabic word lists, Common Phrases test, the Multisyllabic and Lexical Neighborhood (MLNT, LNT) tests, and the Banford-Kowal-Bench (BKB) sentence test., Results: One-way analyses of variance revealed significant improvement in open-set speech recognition in children able to perform measurement tasks., Conclusions: The Nucleus CI24M cochlear implant provides significant benefit to children after short-term use.

The auditory brain stem implant has been used effectively to provide hearing sensations to individuals deafened by bilateral auditory nerve tumors (neurofibromatosis type 2). During tumor removal, the auditory brain stem implant is implanted into the lateral recess of the fourth ventricle by a translabyrinthine approach and is intended to stimulate auditory neurons of the cochlear nucleus complex. A new eight-electrode multichannel auditory brain stem implant was developed and evaluated in 20 patients who had at least 3 months' experience with the device. Mild nonauditory sensations (primarily tingling in the head or torso) were encountered in some instances but could be managed by changing the stimulus characteristics or excluding electrodes. Testing of perceptual performance indicated significant benefit from the device for communication purposes, including sound-only sentence recognition scores in three patients ranging from 49% to 58% and ability to converse on the telephone. These results indicate that significant auditory benefit can be derived from direct multichannel electrical stimulation of the auditory portion of the human brain stem.

A series of 73 postlinguistically deafened adults and 34 prelinguistically deafened children were evaluated with the Spectral Peak (SPEAK) coding strategy of the Nucleus 22-channel cochlear implant. The adults who received consecutive implants demonstrated rapid acquisition of open-set speech recognition skills in the initial postoperative period. Group mean sentence recognition improved to 53.5% (n = 52) after 2 weeks, 62.1% (n = 55) after 1 month, 69.8% (n = 57) after 3 months, and 74.4% (n = 42) after 6 months of use. At the 6-month evaluation interval, 43% of subjects scored greater than 90% on sound-alone sentence recognition in quiet and only one patient (2.4%) scored less than 10%. Mean monosyllabic word recognition was 35.6% after 6 months of use. The 34 prelinguistically deafened children were converted from the Multipeak strategy to Spectral Peak strategy at four large pediatric implant centers. After 6 months of using the new coding strategy, the children demonstrated significant improvements in their speech perception abilities.

A model of auditory performance and a model of ganglion cell survival in postlinguistically deafened adult cochlear implant users are suggested to describe the effects of aetiology, duration of deafness, age at implantation, age at onset of deafness, and duration of implant use. The models were compared with published data and a composite data set including 808 implant users. Qualitative agreement with the model of auditory performance was found. Duration of deafness had a strong negative effect on performance. Age at implantation had a slight negative effect on performance, increasing after age 60 years. Age at onset of deafness had little effect on performance up to age 60. Duration of implant use had a positive effect on performance. Aetiology had a relatively weak effect on performance.

A new speech processing strategy (SPEAK) has been compared with the previous Multipeak (MPEAK) strategy in a study with 24 postlinguistically deafened adults. The results show that performance with the SPEAK coding strategy was significantly better for 58.31% of subjects on closed-set consonant identification, for 33.3% of subjects on closed-set vowel identification and open-set monosyllabic word recognition, and for 81.8% of subjects on open-set sentence recognition in quiet and in competing noise (+ 10 dB signal-to-noise ratio). By far the largest improvement observed was for sentence recognition in noise, with the mean score across subjects for the SPEAK strategy twice that obtained with MPEAK.

A new 8-electrode prosthesis has been developed for individuals deafened by bilateral auditory nerve tumors (neurofibromatosis-2). Twelve patients have received the multichannel auditory brain stem implant at House Ear Institute since 1992, 11 of whom receive useful auditory sensations. Processor fitting includes scaling and ranking of electrode-specific pitch sensations, and determination of any nonauditory sensations. Two representative patients differing in experience and number of usable electrodes are compared in terms of range of auditory sensations and speech perception performance. An inexperienced patient with two electrodes using a new speech-processing strategy (Speak) performed comparably to an experienced patient with six electrodes using an earlier feature-extraction processor.

Sixty-three postlinguistically deaf adults from four English-speaking countries participated in a 17-week field study of performance with a new speech coding strategy, Spectral Peak (SPEAK), and the most widely used strategy, Multipeak (MPEAK), both of which are implemented on wearable speech processors of the Nucleus 22 Channel Cochlear Implant System; MPEAK is a feature-extraction strategy, whereas SPEAK is a filterbank strategy. Subjects' performance was evaluated with an experimental design in which use of each strategy was reversed and replicated (ABAB). Average scores for speech tests presented sound-only at 70 dB SPL were higher with the SPEAK strategy than with the MPEAK strategy. For tests in quiet, mean scores for medial vowels were 74.8 percent versus 70.1 percent; for medial consonants, 68.6 percent versus 56.6 percent; for monosyllabic words, 33.8 percent versus 24.6 percent; and for sentences, 77.5 percent versus 67.4 percent. For tests in noise, mean scores for Four-Choice Spondees at +10 and +5 dB signal-to-noise ratio (S/N) were 88.5 percent versus 73.6 percent and 80.1 percent versus 62.3 percent, respectively; and for sentences at +15 dB, +10, and +5 dB S/N, 66.5 percent versus 43.4 percent, 61.5 percent versus 37.1 percent, and 60.4 percent versus 31.7 percent, respectively. Subjects showed marked improvement in recognition of sentences in noise with the new SPEAK filterbank strategy. These results agree closely with subjects' responses to a questionnaire on which approximately 80 percent reported they heard best with the SPEAK strategy for everyday listening situations.

Results from 80 pediatric subjects with 12 months of experience wearing the Nucleus multichannel cochlear implant are presented. The data suggest that children demonstrate statistically and clinically significant benefit across a broad spectrum of abilities with the implant. Significant postoperative improvement was demonstrated by 66 percent (51 of 77), 63 percent (45 of 72), and 46 percent (27 of 59) of subjects tested on suprasegmental (prosodic), closed-set and open-set tests, respectively. Forty-nine percent of subjects tested improved when lipreading was combined with sound from the implant, compared with lipreading alone. Children who were deaf at an early age or who had longer duration deafness tended to demonstrate poorer performance on the more difficult perceptual tasks after 12 months of implant experience. However, preliminary evidence suggests that continued improvements by congenital and prelinguistic subjects over longer periods of time may reduce performance differences between subjects with early and later onset deafness.

The purpose of this study is to report on five speech production protocols collected as part of the Food and Drug Administration's Clinical Trials for the Nucleus multichannel cochlear implant. Sixty-one children, ranging in age from 2.4 years to 17.8 years, participated. Speech measures included nonsegmental and segmental portions of the Phonetic Level Speech Evaluation, the Phonologic Level Speech Evaluation, speech intelligibility, and an experimental condition examining speech produced with the device turned on versus off. Seventy-seven percent of the children improved on at least one-third of the speech production measures. Significant improvements in the ability to imitate prosodic characteristics were observed for 31.1 percent of the children. Improvements in the ability to imitate speech sounds were found for 66.7 percent of the children. Examination of phonologic skills acquired during spontaneous speaking improved for 55.6 percent of the children. Speech intelligibility improved in 62.9 percent of the children after implantation. More centralized second formant frequencies were observed in vowels produced with the speech processor turned off, as opposed to on, in all 13 of the children tested on this protocol. Data from this study suggest a multichannel cochlear implant may assist many children in developing better speech.

A total of 218 children have been implanted to date with the Nucleus multichannel cochlear implant. All children have stimulated and there have been only 6 complications that required subsequent surgical intervention. After 12 months of experience with the device, significant improvements in auditory-alone speech perception were demonstrated by 66 percent of subjects tested on prosodic and closed-set measures and by 46 percent of subjects tested for open-set word recognition.

Noninvasive, extratympanic electrocochleography (ECoG) was performed on 13 normal-hearing subjects with three different types of ECoG electrodes. Two of these electrodes, the Life-Tech and Axonics-3M designs are commercially available, and widely used clinically. The third electrode, the TM electrode, is a newly designed system intended to be placed directly onto the tympanic membrane. The purpose of this study was to assess the clinical performance of these different electrodes with particular attention to response amplitudes, response variability, and practical ease of use. The results indicate that the TM electrode provides improved ECoG response amplitudes while minimizing clinical preparation time.

A group of 101 otologically normal infants and children were evaluated with low-frequency harmonic acceleration (HA) to determine the feasibility of use of this procedure in evaluation of vestibular function in a pediatric population. Ninety-six of the subjects were successfully tested and normative data are presented. A maturational trend was noted (in the presence of nystagmus) in subjects up to 10 months of age and in the phase-lag measurement up to approximately 4 years of age.