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Objectives: Epidemiologic studies of the prevalence and risk factors of voice disorders in the general adult population are rare. The purpose of this investigation was to 1) determine the prevalence of voice disorders, 2) identify variables associated with increased risk of voice disorders, and 3) establish the functional impact of voice disorders on the general population. Study Design: Cross-sectional telephone survey. Methods: A random sample (n = 1,326) of adults in Iowa and Utah was interviewed using a questionnaire that addressed three areas related to voice disorders: prevalence, potential risk factors, and occupational consequences/effects. Results: The lifetime prevalence of a voice disorder was 29.9%, with 6.6% of participants reporting a current voice disorder. Stepwise logistic regression identified specific factors that uniquely contributed to increased odds of reporting a chronic voice disorder including sex (women), age (40–59 years), voice use patterns and demands, esophageal reflux, chemical exposures, and frequent cold/sinus infections. However, tobacco or alcohol use did not independently increase the odds of reporting of a chronic voice disorder. Voice disorders adversely impacted job performance and attendance, with 4.3% of participants indicating that their voice had limited or rendered them unable to do certain tasks in their current job. Furthermore, 7.2% of employed respondents reported that they were absent from work 1 or more days in the past year because of their voice, and 2% reported more than 4 days of voice-related absence. Conclusions: The results of this large epidemiologic study provide valuable information regarding the prevalence of voice disorders, factors that contribute to voice disorder vulnerability, and the functional impact of voice problems on the general population.

Objective To evaluate the efficacy of crosslinked hyaluronan (HA) hydrogels that contained covalently-bound mitomycin C (MMC) in reducing postoperative adhesions in a rat uterine horn model. Design Two independent parameters were investigated: [1] the quantity of MMC in preformed crosslinked hydrogel films and [2] the efficacy of intraperitoneal injection of in situ crosslinkable solutions. Setting University animal research facility. Animal(s) Female Wistar rats. Intervention(s) Injuries (3 × 10 mm) were made to contacting serosal surfaces of the medial uterine wall musculature in female rats. Two treatment protocols were used. In the first, sterile crosslinked HA films that contained different MMC loadings (0, 0.5%, and 2%) were applied to two injured uterine horns; control animals received no films. In the second protocol, MMC-loaded crosslinked HA gels that contained different MMC loadings (0.31%, 0.625%, and 1.25%) were spread on the site of uterine horn injury (1 mL); then, an additional 4 mL of the same formulation was injected into the peritoneal cavity after abdominal closure. Control animals were injected with 5 mL of buffer only. Main Outcome Measure(s) Extent of postoperative adhesions between uterine horns and with surrounding tissues and organs. Result(s) Mitomycin C–loaded crosslinked HA films and in situ crosslinked gels were more effective in reducing postoperative adhesion formation than were buffer controls or crosslinked HA films without MMC. Conclusion(s) Mitomycin C–loaded crosslinked HA films and gels reduced formation of postoperative intraperitoneal adhesions.

Objectives/Hypothesis: The objective was to determine treatment dose and time-dependent effects of injected mitomycin C on extracellular matrix fibroblasts, collagen, and fibronectin, important mediators in the wound healing response, in a rat cutaneous wound model. Study Design: A prospective, controlled animal study. Methods: Forty rats were injected with three different doses (0.4, 2.3, and 5.0 mg/mL) of mitomycin C at three different wound sites with a fourth wound site receiving saline as a control. The rats were grouped to have their tissue harvested at five different dates ranging from 1 week to 8 weeks. After death, samples from the wound site underwent Western blot analysis for collagen and fibronectin and histological analysis measuring fibroblast apoptosis. Results: Over an 8-week period, collagen and fibronectin significantly decreased and fibroblast apoptosis significantly increased. No correlation was found between the injected dose of mitomycin C and either the extracellular matrix protein concentration or the rate of fibroblast apoptosis. Conclusion: Mitomycin C demonstrated a long-term effect in a wound, inhibiting collagen and fibronectin production and inducing apoptosis. Use of mitomycin C in excess of 0.4 mg/mL did not alter protein concentrations or rate of apoptosis.

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. Study Design: Prospective investigation in an animal model. Methods: A 6 mm wound was created in bilateral maxillary sinuses of 17 New Zealand white rabbits. CS hydrogel (case) and no dressing (control) were randomly assigned to one side each as wound treatment. Wounds were examined ex vivo at 2, 4, 6, 10, and 14 day postinjury intervals. Wound diameter was measured microscopically by a blinded investigator. Representative specimens were examined histologically. Results: The CS disc was partially integrated into the wounds at the 4-day interval and completely integrated by the 6-day interval. The average wound diameters for the case versus control side were similar at 2 days (3.75 mm vs. 4.42 mm) but differed significantly at 4 days (2.86 mm. vs. 3.80 mm., P = .035). At 6 days, the wounds could not be discerned on either the case or control sides. However, histologic analysis revealed accelerated healing with the CS treatment. The treated wounds displayed respiratory epithelium as opposed to the squamous epithelium exhibited on the untreated sides. Conclusions: Despite some limitations, the New Zealand white rabbit is an effective model for the study of sinonasal wound healing. CS hydrogel accelerates wound healing in sinonasal mucosa at a 4-day endpoint. We propose that the CS hydrogel acts as a surrogate extracellular matrix, serving as a repository for cytokines and growth factors produced by the regenerating mucosa. It may also provide a structural framework for fibroblasts and epithelial regeneration. Further study is necessary to establish this relationship.

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. Prevalence—the number of cases per population at risk at a specific time—was determined. The prevalence of reporting a current voice problem was significantly greater in teachers compared with nonteachers (11.0% vs. 6.2%), χ 2 (1)=18.2, p 2 (1)=215.2, p 2 (1)=55.3, p 2 (1)=20.9, p 4 weeks in duration), compared with acute voice disorders (20.9% vs. 13.3%), χ 2 (1)=8.7, p =.003. To assess the association between past voice disorders and possible risks, adjusted odds ratios (ORs) were estimated using multiple logistic regression. The results identified that being a teacher, being a woman, being between 40 and 59 years of age, having 16 or more years of education, and having a family history of voice disorders were each positively associated with having experienced a voice disorder in the past. These results support the notion that teaching is a high-risk occupation for voice disorders. Important information is also provided regarding additional factors that might contribute to the development of voice disorders.

Summary: 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. Using a rabbit model, interstitial proteins decorin, fibromodulin, and fibronectin were examined immunohistologically, two months postinduction of vocal fold scar by means of forcep biopsy. Significantly decreased decorin and fibromodulin with significantly increased fibronectin characterized scarred vocal fold tissue. The implications of altered interstitial proteins levels and their affect on the fibrous proteins will be discussed in relation to increased vocal fold stiffness and viscosity, which characterizes vocal fold scar.

Summary: Clinicians frequently offer advice to performers and voicedisordered 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. PTP is the minimum subglottal pressure required to initiate vocal fold oscillation, and the lowering of PTP is assumed to correspond to physiologically more efficient phonation and reduced phonatory effort. Over a 3-week period, participants were tested on three separate occasions (at 1-week intervals). On each occasion, a different nebulized treatment was administered. PTP for both comfortable and high fundamental frequency productions was measured using an oral pressure-flow system (Perci-Sars, MicroTronics Corp., Chapel Hill, NC). Analysis of the results revealed that Mannitol, an agent that encourages osmotic water flux to the luminal airway surface, lowered PTP immediately after its administration (ie, p 0.071, for high-pitched productions only). However, the duration of its PTP lowering effect was less than 20 minutes. The other two substances did not demonstrate any significant postadministration effect on PTP.

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. Self-ratings of voice (Voice Handicap Index) and swallowing (M. D. Anderson Dysphagia Inventory) were completed, as well as independent auditory-perceptual ratings of voice and speech recordings. Resuits: Although no significant difference between Voice Handicap Index, M. D. Anderson Dysphagia Inventory, and listener ratings was identified based on tumor site and irradiation status, there was a trend toward poorer outcomes in patients who received adjuvant radiation therapy. Whereas the patients having supraglottic cancer tended to report better voice but poorer swallowing outcomes, the glottic cancer group displayed the opposite pattern. Severity on Voice Handicap Index correlated significantly with listener severity ratings of speech, suggesting that the patients' perception of their voice handicap was similar to the listeners' judgments of their speech severity. Conclusions: The results suggest the following trends: 1) Adjuvant radiation therapy was associated with poorer outcomes for voice, speech, and swallowing and may be associated with more impairment than surgery alone and 2) poorer outcomes on voice and swallowing were observed for the glottic and supraglottic cancer groups, respectively. To bolster these preliminary findings, additional outcomes studies in patients treated with conservation therapy are needed.

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. Gene expression profiles, a fundamental part of biochip development, are now commonly performed in some voice laboratories. Tissue engineering initiatives have led to the ability to grow and work with laryngeal fibroblasts. Because of the extreme conditions (intense vibration, exposure to inhalants, etc.) that vocal fold fibroblasts tolerate, engineering living lamina propria of vocal folds is complex and challenging. Research efforts to explore these conditions in-vitro and their effect on fibroblast growth is detailed. In summary, applying tools from geno...

The design of 4th Generation Cellular Communication Systems will face many challenges, including the need to achieve very high spectrum efficiency when compared to 3rd Generation cellular systems. In this paper, we investigate the fundamental limits of DSSS-CDMA versus TDMA for achieving high spectrum efficiency by presenting the capacity regions for each including the effects of multiple transmit and receive antennas. To assess the channel capacity region for local area and wide area coverage, a channel model based upon uncorrelated Rayleigh fading and model with a strong spatial correlation and Ricean component are evaluated. For multiple transmit and receive antennas, both open loop and closed loop capacity regions are assessed, where the closed loop capacity assumes channel state information at the transmitter and optimum power allocation. Conclusions from the work include an assessment of what approaches hold the best promise for achieving high spectrum efficiency for future cellular communication systems.

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. Fibronectin is a ubiquitous glycoprotein found most abundantly in the extracellular matrix of regenerating, healing, and embryonic tissue. Vast evidence supports the fact that fibronectin participates in many diverse functions throughout the body that are relevant to vocal fold biology. This article introduces the structure of fibronectin and its isoforms and provides an introduction to some of the many functions it plays. It also reviews the evidence about fibronectin's place in vocal folds and vocal fold pathology. It discusses fibronectin's presence in vocal nodules, vocal polyps, vocal scarring, and Reinke's edema, and reviews the data on its role in mucosal wave impairment. Lastly, it discusses preliminary microarray data that show gene expression for fibronectin to be upregulated in true vocal folds when compared to false vocal folds.

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. Specifically, research into the role of HA in laryngology indicates that it has profound effects on the structure and viscosity of vocal folds. This article provides an introduction to the structure and biological functions of HA and its importance in voice. In addition, an overview of the pharmaceutical applications of HA is discussed.

Transmit diversity (TD) is one of the key contributing technologies to defining the ITU endorsed 3G systems W-CDMA and cdma2000. Spatial diversity is introduced into the signal by transmitting through multiple antennas. The antennas are spaced far enough apart that the signals emanating from them can be assumed to undergo independent fading. In addition to diversity gain, antenna gain can also be incorporated through channel state feedback. This leads to the categorization of TD methods into open loop and closed loop methods. Several methods of transmit diversity in the forward link have been either under consideration or adopted for the various 3G standards. This article describes the concept of transmit diversity and explains the features of selected TD techniques.

Although a great deal of research exists regarding lamina propria composition, no report exists that relates gene expression in benign laryngeal lesions to phenotypic markers. In this study, messenger RNA profiles for extracellular matrix proteins — procollagen I, collagenase, elastase, fibronectin, fibromodulin, decorin, hyaluronic acid synthase 2, and hyaluronidase — were completed on 5 polyps and 4 Reinke's edema specimens. These genotypic profiles were correlated to a videostroboscopic parameter of mucosal wave stiffness, which was used as a measurement of phenotypic expression. Polyps, characterized by stiffer mucosal waves, had higher levels of gene expression, whereas stiffer mucosal wave scores for Reinke's edema were associated with lower gene activity levels. This study supports the hypothesis that there is a relationship between genotypic expression found in polyps and Reinke's edema and phenotype as defined by a loss of or a decreased mucosal wave. The study also gives clues as to the proteins responsible for the phenotype.

Scarring of the vocal fold causes considerable dysphonia and presents significant treatment challenges. A rabbit model was developed to investigate the histologic ultrastructure and rheologic properties of the scarred vocal fold lamina propria. Eleven rabbit larynges were scarred by means of forcep biopsy. Sixty days postoperatively, the rabbits were sacrificed and their vocal folds were harvested. Histological analysis of the scarred and normal lamina propria was completed for collagen, procollagen, elastin, and hyaluronic acid. Linear viscoelastic shear properties of the tissues were also measured, including elastic shear modulus and dynamic viscosity. Compared to normal vocal fold lamina propria, scarred tissues demonstrated significantly less collagen, an increase in procollagen, and a decrease in elastin. Rheologically, both elastic shear modulus and dynamic viscosity were significantly higher for the scarred tissues. Increased stiffness and viscosity do not appear to result from an increase in collagen, but rather appear to be related to the presence of new, disorganized collagen scaffolding. Results are interpreted in terms of the possible role of interstitial proteins in the etiology of increased stiffness and viscosity, which requires further investigation. This animal model should allow for systematic future investigations of vocal fold scarring and its treatment.

Complications of adenoidectomy include velopharyngeal inadequacy and nasopharyngeal stenosis. The evaluation of velopharyngeal inadequacy requires the participation of speech pathology in assessing the problem and formulating a treatment plan. Nasal endoscopy findings are crucial in this process, and a decision tree based on these findings is given. The surgical treatment options for velopharyngeal inadequacy after adenoidectomy are discussed. The less common problem of nasopharyngeal stenosis and an approach to its treatment is also presented.

Primary fibroblast cell cultures were established from lamina propria of human vocal fold and tracheal scar. There exists a crucial need to provide new tools for studying voice biology, and one of the first steps is the development of a human primary laryngeal cell culture bank. Because cell lines can lose their differentiated phenotype in culture across passages, documentation of gene expression must be determined for passage populations, for us to have knowledge of cell behavior in vitro. Comparison of messenger RNA gene expression of extracellular matrix proteins (procollagen I, collagenase, elastin, hyaluronic acid synthase 2, hyaluronidase, fibronectin, cd44, fibromodulin, anddecorin) across cell passages (3, 4, 5, 6, 10, and 12 for normal lamina propria and 3, 4, 5, 6, and 10 for tracheal scar) revealed varied growth patterns. Cytogenetic analysis demonstrated relative stability of the karyotypes across passages for the tracheal scar cell cultures, whereas the karyotypes of the normal lamina propria fibroblasts showed instability in in vitro cultures. Recommendations for use of primary cell cultures for further studies of gene expression are made.

Objective: This study examined the influence of hyaluronic acid (HA) on the biomechanical properties of the human vocal fold cover (the superficial layer of the lamina propria). Study design: Vocal fold tissues were freshly excised from 5 adult male cadavers and were treated with bovine testicular hyaluronidase to selectively remove HA from the lamina propria extracellular matrix (ECM). Linear viscoelastic shear properties (elastic shear modulus and dynamic viscosity) of the tissue samples before and after enzymatic treatment were quantified as a function of frequency (0.01 to 15 Hz) by a parallel-plate rotational rheometer at 37°C. Results: On removing HA from the vocal fold ECM, the elastic shear modulus (G′ ) or stiffness of the vocal fold cover decreased by an average of around 35%, while the dynamic viscosity (η′) increased by 70% at higher frequencies (>1 Hz). Conclusion: The results suggested that HA plays an important role in determining the biomechanical properties of the vocal fold cover. As a highly hydrated glycosaminoglycan in the vocal fold ECM, it likely contributes to the maintenance of an optimal tissue viscosity that may facilitate phonation, and an optimal tissue stiffness that may be important for vocal fundamental frequency control. Significance: HA has been proposed as a potential bioimplant for the surgical repair of vocal fold ECM defects (eg, vocal fold scarring and sulcus vocalis). Our results suggested that such clinical use may be potentially optimal for voice production from a biomechanical perspective. (Otolaryngol Head Neck Surg 2001;124:607-14.)

In humans, vocal tissue stiffness increases with age, suggesting a possible contribution of age-associated variations in vocal fold collagen turnover to voice senescence. The underlying mechanisms remain to be explored. With the use of reverse-transcriptase polymerase chain reaction (RT-PCR), collagen subtypes expressed in rat vocal folds were determined, and messenger RNA (mRNA) levels of collagens (types I, III, IV, and V), collagen-degrading proteinases (collagenase 3, gelatinase A and B), and tissue inhibitors of metalloproteinases (TIMP-1 to TIMP-4) were measured in vocal folds of neonatal, adult, and elderly rats. Collagens I, III-VIII, XV, XVII, and XVIII are abundantly expressed, whereas collagens II, IX, X, and XI are absent in rat vocal folds. Messenger RNA levels of collagens I, III, IV, and V and collagen-degrading proteinases in the vocal folds of the adult rats are significantly lower than those in the neonates. These mRNA levels show further decline in the vocal folds of the elderly rats, but only the decrease in mRNA levels of collagens I and V significantly differ from the adult levels. There are no marked age-related alterations in vocal fold levels of TIMP mRNAs, and the tissue variation in the gene expression of the aforementioned molecules is minute. Rat vocal folds display tissue-specific expression of collagen genes. Diminished gene expression for collagens and proteinases and unchanged gene expression for TIMPs indicate a slowdown in collagen turnover that may increase the cross-linking of collagen molecules. This observation may explain in part the stiffness that occurs with aging in human vocal folds.

Teachers commonly report voice problems and often seek medical assistance for voice-related complaints. Despite the prevalence of voice disorders within this occupation, there are no studies evaluating the effectiveness of treatment programs designed to remedy the voice problems of teachers. To assess the functional effects of two voice therapy approaches, 58 voice-disordered teachers were randomly assigned to 1 of 3 groups: vocal hygiene (VH, n =20), vocal function exercises (VFE, n =19), and a nontreatment control group (CON, n =19). Subjects completed the Voice Handicap Index (VHI) —an instrument designed to appraise the self-perceived psychosocial consequences of voice disorders—before and following a 6-week treatment phase. The VFE and VH subjects also completed a posttreatment questionnaire regarding the perceived benefits of treatment. Only the group who adhered to the VFE regimen reported a significant reduction in mean VHI scores ( p p p p

This paper will provide a review of aspects of vocal aging within the context of general body aging and describe two data sets related to the aging voice. Data will be presented which document pre- to posttreatment improvement in select voice characteristics (sound pressure level, subglottal air pressure, thyroarytenoid laryngeal muscle activity and voice quality) following application of an intensive voice treatment program (the LSVT®) to 3 individuals with aged voice. Additionally, physiological data (forced expiratory volume, visual accommodation, bone density, taste discrimination, white blood count and resting heart rate) and select perceptual (perceived age) and acoustic measures (reflecting both cycle-to-cycle and longer-term intensity and frequency stability) from 67 subjects will be reviewed from the work of Gray and colleagues to document the differential impact of the global aging process across organ systems including the aging voice.

The composition of the lamina propria in human vocal folds has been shown to affect vocal performance. Collagen plays a significant role in the biomechanical effects of the lamina propria. Specifically, it lends tensile strength to the rapidly oscillating fold. We obtained from a state medical examiner 38 larynges from men and women in infant, adult, and geriatric age groups. We stained the vocal folds for collagen using a picric acid stain and studied them using an image analysis system. Distributions of collagen were measured from the superficial to deep layers (from epithelium to vocalis muscle) within the lamina propria. The data showed an increase in collagen content from infant to adult stages. Infant folds had about 51 % of the collagen found in all adults and in geriatric patients (p < .001). There was no significant difference between adult and geriatric folds (p < .16). There was, however, a gender difference in the amount of collagen in both adult and geriatric specimens. Female adult and geriatric folds had about 59% of the collagen found in male adult and geriatric folds (p < .001). The distribution pattern of collagen showed that most of the collagen was present in the deep layer. From these data we conclude that there are age-related and gender-related differences between male and female infant, adult, and geriatric vocal folds. Stress-strain performance studies need to be correlated with histologic findings to better study the phonetic implications of these findings.

The core biologic processes affecting vocal folds are cellular. Although it is rare for a voice professional to understand that vocal health or illness often depends on cellular well-being or dysfunction, the laryngologist must be aware of this relationship. Almost every voice illness can be related either to a tissue change or disorder or to suboptimal or inappropriate functional use of normal or abnormal tissue. A physician must decide whether the tissue is diseased, whether it is being used suboptimally, or both. If the tissue is diseased, treatment should attempt to restore cellular health. Although this article summarizes the information currently available regarding cellular activity, vocal health, and voice disorders, detailed knowledge of these issues is often lacking. The study of vocal health and vocal function has had a decidedly different history than that of many other organ systems. This difference arises in part from the large volume of research performed in this field by speech scientists, speech pathologists, and persons with engineering backgrounds. As these investigators have pioneered research in this field, they have used the tools with which they are most comfortable and experienced. Consequently, there exists a rich foundation in signal processing and acoustical analysis of voice and vocal problems. A substantial foundation is also being developed in other areas of science, such as computer modeling, and in integrated research, as found in the neuromotor field. Voice research at a biologic cellular or molecular level, however, has not been conducted with the same degree of interest. The author hopes that this article will help clinicians understand the biologic and tissue basis for vocal health and vocal pathology and stimulate research in this area. The vocal folds are composed of various tissue types: epithelium, lamina propria, striated muscle, nerves, vascular structures, and cartilage. Although each of these tissue types is important, this article focuses on the epithelium and lamina propria. Pathologic vocal conditions that are related to muscle dysfunction are integrated into the neuromuscular system and often have a neurologic basis for their disorder. Such diseases are beyond the scope of this article. On the other hand, most vocal lesions originate in the lamina propria. The lamina propria is certainly an active and vibrant structure which deserves attention.

Summary There has been an ongoing effort to describe the physiologic factors associated with perceived and/or measured human voice changes that occur with age. In our study we focused on possible endocrine involvement on voice by using immunohistochemical staining to observe hormone receptor presence in vocal folds from 42 deceased subjects ( fresh cadavers ), male and female, ranging in age from 2 months to 82 years (average 37.7 years). On statistical analysis, age and gender were found to be associated with progesterone receptor staining of the glandular nuclei (young>old P = 0.013; male>female, P = 0.060). Gender was associated with androgen receptor staining in glandular cytoplasm (male>female, P = 0.014) and progesterone receptor staining in the epithelial cytoplasm (male>female, P =0.039). No statistical significance was noted in other categories. Conclusion: Hormone receptors are found in the nucleus and cytoplasm of cells in the vocal fold with statistically significant differences in age and gender distribution .

To determine whether a natural plane of dissection occurs in the normal human vocal fold, semi-blunt instruments (Bouchayer laryngeal dissectors) were used to dissect the lamina propria. The depth of the plane of dissection was correlated with the elastin fibre concentration to determine whether the plane occurred at a predictable point in the elastin concentration as it increased between the superficial and middle layers. Eight human larynges were dissected using an operative microscope. The dissection plane consistently occurred between 23-50% depth into the lamina propria. No consistent correlation was found with the elastin fibre concentration. The depth of the plane of dissection has an interesting association with age: dissection planes occurred more superficially in older specimens.

Severe pharyngeal stenosis is a debilitating condition associated with apnea and dysphagia. Treatment options include local flaps and free mucosal grafts. We present 2 cases of severe stenosis, apparently from adenotonsillectomy, that failed more conservative repairs. Both were treated successfully with a sternocleidomastoid myocutaneous flap rotated in through a lateral pharyngotomy. No further treatment has been required. Technical considerations and operative planning are discussed.

Velopharyngeal insufficiency (VPI) can be treated surgically with various operations. This article describes the use of a superiorly based folded pharyngeal flap for posterior wall augmentation to treat VPI. This is a retrospective study indicating that a folded flap to augment the posterior wall is likely to be as effective as other surgical techniques to treat small velopharyngeal gaps. Patients selected for this procedure had very good velar motion. Postoperative nasometric zoo passage scores improved by an average of 18 over preoperative scores. Additionally, a correlation was found between age and nasometry improvement after surgery. Younger patients did better. Patients in whom VPI was caused by adenoidectomy did well. The 2 syndromic patients did not do as well when treated with this type of operation.

Treatment of challenging laryngeal disorders, such as lamina propria loss or neuromuscular dysfunction, may require novel approaches and techniques. This paper discusses an evolution of experimental techniques for treatment of lamina propria loss and use of the minithyrotomy. These techniques have been used for surgical access for lamina propria substitution, as well as placement of stimulating electrodes. The minithyrotomy is tolerated well by patients, provides access for microscopic instruments with the surgeon's hand close to the tissue of interest, avoids intralaryngeal mucosal incisions, and lines up the direction of dissection in an anterior-to-posterior orientation. This orientation is favorable for particular situations herein discussed. We present anatomic and physiologic concepts relevant to the surgical treatment of lamina propria dysfunction, as well as presenting our clinical experience. This paper is not intended to state how these difficult problems should be handled, but rather, to present our experience in techniques that may prove useful through further development.

The composition of the lamina propria in human vocal folds has been shown to affect vocal performance. Elastin plays a significant role in the biomechanical effects of the lamina propria. We obtained 19 larynges from the state medical examiner from subjects whose cause of death was unrelated to the trachea and laryngeal regions. The sample contained male and female subjects in the infant, adult, and geriatric age groups. We stained the vocal folds for elastin with Verhoeff’s elastic tissue stain and studied them with use of an image analysis system configured for light microscopy. Distributions of elastin were measured from superficial to deep within the lamina propria (from epithelium to vocal muscle). These elastin distributions were then compared with the use of statistical software. The data showed that there was an increase in elastin content from the infant through geriatric stages. No gender-related differences were found. Infant folds had about 23% of the elastin found in adults, and geriatric subjects had about 879% of the elastin found in adults. Both of these results were statistically significant (p

A comparison between models for the substrate−catalyst adduct in hydrodenitrogenation (HDN) catalysis is made with respect to oxygen vs sulfur ancillary ligands. Reacting [η2(N,C)-NC5tBu3H2]Ta(OAr)...

Studies have shown that the lamina propria plays an important role in voice production. Recent studies have analyzed the presence of different proteins and quantified their extent in the lamina propria, but no similar study has yet been done on cellular makeup. The distribution of three different cell types in the lamina propria of 22 human vocal folds was studied. These types are fibroblasts, macrophages, and myofibroblasts. The roles of these cells in the extracellular matrix are described. Their distribution was quantified with use of an image-analysis system. We arbitrarily divided the lamina propria into five sections (each representing 20% of the lamina propria) and compared cell numbers among these sections. Gender comparisons were also made. From these studies it is evident that the cellular distribution in the lamina propria is not uniform. Fibroblasts were more abundant in the deepest 20% of the lamina propria (p0.008), myofibroblasts were more abundant in the most superficial 20% (p0.016), and in the 36% of our samples that contained macrophages in the lamina propria, there was a significantly higher number of macrophages in the first 20% of the lamina propria (p0.003). The only significant gender difference was that women had twice as many macrophages in the most superficial 20% of the lamina propria as men (p0.05). The higher myofibroblast activity in the first 20% could indicate that the superficial layer is a region of constant repair. The increased number of macrophages in the superficial layer likely indicates an inflammatory response to inhalants (because of the role of macrophages in the inflammatory response and the fact that only 36% of the patients showed any macrophage activity at all).

Treatment of (TTP)Ti(eta(2)-RCtbd1;CR) (R = Et or Ph) with PhN=NPh results in formation of the azobenzene adduct (TTP)Ti(eta(2)-PhN=NPh) (1) in good isolated yield. Complex 1 reacts with (TTP)Ti(eta(2)-RCtbd1;CR) at elevated temperatures to cleanly afford 2 equiv of the phenylimido compound, (TTP)Ti=NPh (2). The azobenzene complex, 1, is also formed in low yields by the reaction of the (TTP)Ti=NPh (2) with excess 1,2-diphenylhydrazine. The electrochemistry of the azobenzene adduct (1) and the phenylimido complex (2) is investigated by cyclic voltammetry experiments.

Facile syntheses of the meso-tetra-p-tolylporphyrin (TTP) complexes trans-(TTP)Ti(THF)(2) (1), (TTP)Sn (2), and trans-(TTP)V(THF)(2) (3) are achieved through homogeneous reduction of high-valent precursors using NaBEt(3)H. The composition of the new compound trans-(TTP)Ti(THF)(2) was determined by spectroscopic and chemical characterization. Ligand displacement reactions of trans-(TTP)Ti(THF)(2) with t-BuNC produced a new Ti(II) complex, trans-(TTP)Ti(t-BuNC)(2). The ligand-binding preference of (TTP)Ti(II)L(n)() (n = 1, 2) is picoline approximately pyridine > t-BuNC > PhCtCPh > EtCtCEt > THF.

Summary The lamina propria of vocal folds are important in voice production. We evaluated the morphologic features of elastin and hyaluronic acid, two important constituents of the lamina propria. Thirty normal human vocal folds were obtained from patients dying of traumatic causes without vocal fold injury. These tissues were immediately prepared for histologic and ultrastructural examination by standard methods. For specific study of the ultrastructure of the layers of the lamina propria, six vocal folds were divided horizontally through the midplane of the lamina propria. We found that the elastin composition of the vocal folds is variable, the largest amount being seen in the midportion on elastin-van Gieson (EVG) staining and ultrastructural evaluation. The superficial layer of the lamina propria contains fewer large elastin fibers. In this region, we found that elastin was predominantly composed of elaunin and oxytalan, which stain poorly with EVG. Using computer-assisted image analysis, we quantified the differences in elastin composition between the layers. The amount of elastin varied between men and women, and these differences could not be accurately measured by the methods employed. Hyaluronic acid was abundant especially in the midportion of the lamina propria and was significantly more abundant in men than women on quantification. The significance of these observations in normal vocal folds is discussed.

Hydrodenitrogenation (HDN) catalysis is the process of removing nitrogen from petroleum feed-stocks in the form of NH3 to provide more processable and environmentally compatible liquid fuels. In practice, HDN is carried out simultaneously with other catalytic hydrotreating reactions such as hydrodesulfurization (HDS), yet HDN is significantly less well-studied than HDS. This contribution provides an overview of the heterogeneous HDN process, then outlines various homogeneous models for hydrodenitrogenation catalysis including binding modes of HDN substrates, catalytic hydrogenation processes and recent CN bond cleavage reactions of nitrogen heterocycles. Emphasis is placed on aryloxide and alkoxide complexes of the early metals that afford some of the best homogeneous models for hydrodenitrogenation catalysis to date.

The reactions of TaCl5 with Me3SiNC9H10 or LiNC9H10, where [NC9H10]- = tetrahydroquinolinyl (the amido anion of tetrahydroquinoline), afford selective preparative routes to the complete series of amido halide complexes of tantalum(V) Ta(NC9H10)nCl5-n for n = 1−5 (compounds 1−5, respectively). The monokis(tetrahydroquinolinyl) complex is isolated as an ether adduct Ta(NC9H10)Cl4(OEt2) while the complexes Ta(NC9H10)nCl5-n (n = 2−5) are found to be base-free, monomeric species. The related complexes of indolinyl [NC8H8]- (the amido anion of indoline), Ta(NC8H8)nCl5-n(THF) for n = 1 (6) or 2 (7), have been prepared from TaCl5, Me3SiNC8H8, and THF. An X-ray structural determination of Ta(NC9H10)2Cl3 (2) reveals that it adopts a trigonal bipyramidal geometry with equatorial amido ligands that are closer to lying parallel (within) than perpendicular to the TBP equatorial plane. Routes to mixed-ligand aryloxide−amide complexes have been developed from either aryloxide or amido precursors but not from both. Thus, ...