Vocal fold paralysis and progressive cricopharyngeal stenosis reversed by cricopharyngeal myotomy.

Three infants with progressive upper esophageal stenosis had bilateral vocal fold paralysis. The patients were apparently normal at birth and without neurologic abnormality. Cricopharyngeal myotomy, followed by serial dilatations, relieved esophageal stenosis and restored the swallowing function.

Occupational risk factors associated with voice disorders among teachers.

Purpose: This study was designed to determine the occupational risk factors associated with voice disorders among schoolteachers, a high-risk population for developing voice problems.

Methods: Telephone interviews were completed by 1243 teachers from Utah and Iowa. Response rates were 98% and 95%, respectively.

Composite articular cartilage engineered on a chondrocyte-seeded aliphatic polyurethane sponge.

To circumvent the reconstructive disadvantages inherent in resorbable polyglycolic acid (PGA)/polylactic acid (PLA) used in cartilage engineering, a nonresorbable, and nonreactive polyurethane sponge (Tecoflex sponge, TS) was studied as both a cell delivery device and as an internal support scaffolding. The in vitro viability and proliferation of porcine articular chondrocytes (PACs) in TS, and the in vivo generation of new articular cartilage and long-term resorption, were examined. The initial cell attachment rate was 40%, and cell density increased more than 5-fold after 12 days of culture in vitro.

Design and validation of a bioreactor for engineering vocal fold tissues under combined tensile and vibrational stresses.

Criteria are outlined for the design of a bioreactor that can simulate the vibrational stresses in vocal fold movement during speech. Requirements are 0-1 mm amplitudes in the 20-200 Hz frequency range, a variable on-off stress regime, and maintenance of tissue viability over several days. The bioreactor uses dual drivers, one for low frequency (or static) strains, and another for high-frequencies vibrational strains.

Chondroitin sulfate hydrogel and wound healing in rabbit maxillary sinus mucosa.

Objectives/hypothesis: Chondroitin sulfate (CS) is a glycosaminoglycan in the extracellular matrix of all vertebrates. A biocompatible, nonimmunogenic, pliable hydrogel preparation of CS has recently been produced and has shown benefit in wound healing in murine and porcine epidermis. The objective of the current experiment is to compare the wound healing properties of CS hydrogel versus no treatment in wounds of the maxillary sinus mucosa.

Voice disorders in teachers and the general population: effects on work performance, attendance, and future career choices.

To examine the frequency and adverse effects of voice disorders on job performance and attendance in teachers and the general population, 2,401 participants from Iowa and Utah (n1 = 1,243 teachers and n2 = 1,279 nonteachers) were randomly selected and were interviewed by telephone using a voice disorder questionnaire. Teachers were significantly more likely than nonteachers to have experienced multiple voice symptoms and signs including hoarseness, discomfort, and increased effort while using their voice, tiring or experiencing a change in voice quality after short use, difficulty projecting their voice, trouble speaking or singing softly, and a loss of their singing range (all odds ratios [ORs] p <.05).

Prevalence of voice disorders in teachers and the general population.

Over 3 million teachers in the United States use their voice as a primary tool of trade and are thought to be at higher risk for occupation-related voice disorders than the general population. However, estimates regarding the prevalence of voice disorders in teachers and the general population vary considerably. To determine the extent that teachers are at greater risk for voice disorders, 2,531 randomly selected participants from Iowa and Utah (1,243 teachers and 1,288 nonteachers) were interviewed by telephone using a voice disorder questionnaire.

Synthesis and biological evaluation of a cross-linked hyaluronan-mitomycin C hydrogel.

A cross-linked hyaluronan (HA) hydrogel that contained a covalently bound derivative of the anti-proliferative drug mitomycin C (MMC) was synthesized and evaluated in vitro and in vivo. The HA-MMC hydrogel was prepared by coupling MMC-aziridinyl-N-acrylate with thiol-modified HA followed by cross-linking with poly(ethylene glycol) diacrylate (PEGDA). MMC was released from 0.

Methodology for rheological testing of engineered biomaterials at low audio frequencies.

A commercial rheometer (Bohlin CVO120) was used to mechanically test materials that approximate vocal-fold tissues. Application is to frequencies in the low audio range (20-150 Hz). Because commercial rheometers are not specifically designed for this frequency range, a primary problem is maintaining accuracy up to (and beyond) the mechanical resonance frequency of the rotating shaft assembly.

DNA microarray gene expression analysis of a vocal fold polyp and granuloma.

Genome-wide transcriptional profiling has important applications in advancing knowledge of vocal fold biology. With the use of DNA microarray technology, analysis of global patterns of gene expression can reveal unexpected networks of coordinated regulation in the extracellular matrix of the lamina propria. Transcriptional gene expression patterns for 2 vocal fold pathologies--vocal fold polyp (VP; N = 1) and vocal fold granuloma (VG; N = 1) were analyzed by means of DNA microarray analysis for 4,632 human genes using another patient's true vocal fold (TVF; N = 1) as a control.

Three treatments for teachers with voice disorders: a randomized clinical trial.

Voice problems are a common occupational hazard of teaching school, yet few studies exist that have objectively evaluated treatment approaches aimed at rehabilitating these occupation-related voice disorders. This randomized clinical trial used patient-based treatment outcome measures to evaluate the effectiveness of three treatment programs. Sixty-four teachers with voice disorders were randomly assigned to 1 of 3 treatment groups: voice amplification using the ChatterVox portable amplifier (VA; n = 25), resonance therapy (RT; n = 19), and respiratory muscle training (RMT; n = 20).

Disulfide-crosslinked hyaluronan-gelatin sponge: growth of fibrous tissue in vivo.

The modification of hyaluronan (HA) and gelatin using dithiobis(propanoic dihydrazide) (DTP) has provided two thiolated macromolecular components of the extracellular matrix (ECM), specifically HA-DTPH and gelatin-DTPH. Blends of these thiolated ECM components were crosslinked in air to form hydrogels that were interpenetrating disulfide-crosslinked networks. Lyophilization of the hydrogels afforded sponge-like macroporous scaffolds suitable for cell attachment and proliferation.

Professional diversity and personal commitments of pediatric otolaryngologists.

Objective: To characterize the time demands and practice patterns of pediatric otolaryngologists.

Design: Prospective survey of members from the American Society of Pediatric Otolaryngology.

Results: The survey response rate was 54% (n = 136) of practicing members of the American Society of Pediatric Otolaryngology.

Molecular subclassification of kidney tumors and the discovery of new diagnostic markers.

We analysed the expression profiles of 70 kidney tumors of different histological subtypes to determine if these subgroups can be distinguished by their gene expression profiles, and to gain insights into the molecular mechanisms underlying each subtype. In all, 39 clear cell renal cell carcinomas (RCC), seven primary and one metastatic papillary RCC, six granular RCC from old classification, five chromophobe RCC, five sarcomatoid RCC, two oncocytomas, three transitional cell carcinomas (TCC) of the renal pelvis and five Wilms' tumors were compared with noncancerous kidney tissues using microarrays containing 19,968 cDNAs. Based on global gene clustering of 3560 selected cDNAs, we found distinct molecular signatures in clear cell, papillary, chromophobe RCC/oncocytoma, TCC and Wilms' subtypes.

Interstitial protein alterations in rabbit vocal fold with scar.

Fibrous and interstitial proteins compose the extracellular matrix of the vocal fold lamina propria and account for its biomechanic properties. Vocal fold scarring is characterized by altered biomechanical properties, which create dysphonia. Although alterations of the fibrous proteins have been confirmed in the rabbit vocal fold scar, interstitial proteins, which are known to be important in wound repair, have not been investigated to date.

An evaluation of the effects of three laryngeal lubricants on phonation threshold pressure (PTP).

Clinicians frequently offer advice to performers and voice-disordered patients aimed ostensibly to manipulate the water content and/or viscosity of the mucus blanket covering the vocal folds. To evaluate the relative effects of three potential laryngeal lubricants on phonatory function (ie, water, Mannitol--an osmotic agent, and Entertainer's Secret Throat Relief (Kli Corp., Carmel, IN)--a glycerin-based product), phonation threshold pressure (PTP) was measured in 18 healthy, vocally normal female participants twice before (baseline) and then four times after 2 ml of each substance were nebulized.

Comparison of human fibroblast ECM-related gene expression on elastic three-dimensional substrates relative to two-dimensional films of the same material.

Three-dimensional elastic substrates were fabricated from a commercially available polyurethane with an internal porosity of approximately 70% and elastic modulus of 27.4+/-2.76 KPa and examined for suitability in vocal fold tissue engineering.

Witnessing a revolution in voice research: genomics, tissue engineering, biochips and what's next!

Due to advances in genomics and tissue engineering, new tools and methods are available for use in voice research. Microarray analysis, a method for examining the expression levels of thousand of genes within 24-48 hours, is a very powerful research tool and has greatly hastened the development of biochips for medical application. The use of microarray analysis in voice research will be discussed and the feasibility of a biochip for voice is presented.

Voice, speech, and swallowing outcomes in laser-treated laryngeal cancer.

Objective: To describe preliminary voice, speech, and swallowing outcomes in patients treated by endoscopic laser excision of laryngeal cancer with or without adjuvant radiation therapy.

Study Design: Retrospective review.

Methods: Seventeen surgically treated patients (five T2 glottic and 12 clinically staged T2 supraglottic squamous cell carcinomas) participated in the study.

Apoptosis and tumor remission in liver tumor xenografts by 4-phenylbutyrate.

4-phenylbutyrate (triButyrate trade mark, PB) a derivative of the short-chain fatty acid, butyrate, possesses anti-tumor activity in vitro in different tumor cell lines. Unlike most cytostatic compounds, PB possesses low toxicity. In order to evaluate possible clinical use of PB in cancer therapy, hepatocarcinoma (Hep3B) and hepatoblastoma (HepT1) cell lines, as well as xenografts derived from those in nude rats, were treated with PB in different dose (1-100 mM) and time regimens.

The effect of mitomycin on extracellular matrix proteins in a rat wound model.

Objective: To evaluate the effect of topical and injected mitomycin on the expression of extracellular matrix proteins by fibroblasts in an early surgical wound model.

Study Design: A prospective, controlled study in a rat wound model.

Methods: Six linear incisions were placed on the backs of each of three Sprague-Dawley rats, and polyvinyl alcohol sponges were implanted.

Identifying cancer-related genes in nasopharyngeal carcinoma cell lines using DNA and mRNA expression profiling analyses.

The goals of this study were to evaluate the potential of detecting cryptic amplification and deletion of cancer-related genes using array-based comparative genomic hybridization (CGH), and to identify candidate cancer genes by combined parallel analyses of copy number and gene expression profiles in nasopharyngeal carcinoma (NPC) cell lines. We established global DNA copy number and mRNA expression profiles on human NPC cell lines using a high-density cDNA microarray. The DNA copy number alterations detected by array CGH were compared to the DNA copy number variations identified by metaphase CGH.

Fibronectin: an interesting vocal fold protein.

A great deal of information is accruing regarding the function of the extracellular matrix. Once thought to be simply a structural entity to surround cells, it is now known to do much more. Fibronectin in particular has received specific attention.

Hyaluronic acid: its role in voice.

The extracellular matrix (ECM), once regarded simply as a structural scaffold, is now recognized as an important modulator of cellular behavior and function. One component that plays a prominent role in this process is hyaluronic acid (HA)--a molecule found in many different tissues. Research into the roles of HA indicates that it plays a key role in tissue viscosity, shock absorption, and space filling.

Voice amplification versus vocal hygiene instruction for teachers with voice disorders: a treatment outcomes study.

Voice problems are common among schoolteachers. This prospective, randomized clinical trial used patient-based treatment outcomes measures combined with acoustic analysis to evaluate the effectiveness of two treatment programs. Forty-four voice-disordered teachers were randomly assigned to one of three groups: voice amplification using the ChatterVox portable amplifier (VA, n = 15), vocal hygiene (VH, n = 15), and a nontreatment control group (n = 14).