Faculty Bibliography

Despite the peripheral and central immaturities that limit auditory processing in juvenile animals, they are able to lateralize sounds using binaural cues. This study explores a central mechanism that may compensate for these limitations during development. Interaural time and level difference processing by neurons in the superior olivary complex depends on synaptic inhibition from the medial nucleus of the trapezoid body (MNTB), a group of inhibitory neurons that is activated by contralateral sound stimuli. In this study, we examined the maturation of coding properties of MNTB neurons and found that they receive an inhibitory influence from the ipsilateral ear that is modified during the course of postnatal development. Single neuron recordings were obtained from the MNTB in juvenile (postnatal day 15-19) and adult gerbils. Approximately 50% of all recorded MNTB neurons were inhibited by ipsilateral sound stimuli, but juvenile neurons displayed a much greater suppression of firing as compared with those in adults. A comparison of the prepotential and postsynaptic action potential indicated that inhibition occurred at the presynaptic level, likely within the cochlear nucleus. A simple linear model of level difference detection by lateral superior olivary neurons that receive input from MNTB suggested that inhibition of the MNTB may expand the response of LSO neurons to physiologically realistic level differences, particularly in juvenile animals, at a time when these cues are reduced

With the multitude of treatment options and emerging technology available for rejuvenation of the lower face and neck, it is often difficult to determine which specific treatment would benefit an individual patient. Monopolar radiofrequency (MRF) nonablative skin rejuvenation is a promising new procedure that is utilized to tighten and contour nonsurgically mild to moderate laxity of the skin of the lower face and neck in patients without significant underlying structural ptosis. In these selected patients and others who wish to avoid surgical treatment modalities, MRF treatment offers a noninvasive method of tightening skin and soft tissue, causing softening of the nasolabial lines, tightening of the jowl, and improving the definition of the cervicomental angle, all without significant recovery time or complications. Further development of MRF technology and refinement of treatment protocols may allow even greater tightening of the skin and more dramatic modulation of underlying deeper structures, making the treatment more universally applicable for patients desiring facial rejuvenation

Genomes of solid tumors are characterized by gains and losses of regions, which may contribute to tumorigenesis by altering gene expression. Often the aberrations are extensive, encompassing whole chromosome arms, which makes identification of candidate genes in these regions difficult. Here, we focused on narrow regions of gene amplification to facilitate identification of genetic pathways important in oral squamous cell carcinoma (SCC) development. We used array comparative genomic hybridization (array CGH) to define minimum common amplified regions and then used expression analysis to identify candidate driver genes in amplicons that spanned <3 Mb. We found genes involved in integrin signaling (TLN1), survival (YAP1, BIRC2), and adhesion and migration (TLN1, LAMA3, MMP7), as well as members of the hedgehog (GLI2) and notch (JAG1, RBPSUH, FJX1) pathways to be amplified and overexpressed. Deregulation of these and other members of the hedgehog and notch pathways (HHIP, SMO, DLL1, NOTCH4) implicates deregulation of developmental and differentiation pathways, cell fate misspecification, in oral SCC development

Beta-6 Integrin, tenascin-C, and MMP-1 (matrix metalloproteinase-1) are invasion-related proteins that are frequently overexpressed in many human malignancies. The objective of this study was to determine whether there is overexpression of these molecules in three types of salivary neoplasms showing markedly different behavior. A total of 55 formalin-fixed, paraffin-embedded archived specimens comprising 19 adenoid cystic carcinomas (ACC), 18 polymorphous low-grade adenocarcinomas (PLGA) and 18 pleomorphic adenomas (PA) were utilized in this study. A standard immunohistochemical technique was used to determine the expression levels of beta-6 integrin, tenascin-C, and matrix metalloproteinase-1 (MMP-1) proteins. Sections were assessed semiquantitatively, and tumors were divided into two groups, low-expressors (0-1+) and high-expressors (2-3+) for statistical analysis. Staining was graded as 0 (<1% positive tumor cells), 1+ (<25% positive tumor cells), 2+ (25-50% positive tumor cells), and 3+ (>50% positive cells). The results showed that the malignant tumors were higher expressors of beta-6 than the benign tumors. ACCs showed significantly higher expression of beta-6 than PAs (p=0.04). No significant difference was observed between ACCs and PLGAs. beta-6 expression was rarely seen in normal salivary gland epithelium and was occasionally present in mucosa overlying the tumors. PAs were high-expressors of tenascin-C with a significant difference relative to ACCs (p=0.03). A majority of tumors in all three tumor types showed high expression of MMP1 with expression significantly greater in the PAs compared to ACCs (p=0.008). We conclude that ACCs and PLGAs express beta-6, tenascin-C, and MMP-1, but that their expression patterns are not significantly different. beta-6 appears to be more closely associated with the malignant tumors, and MMP-1 more closely associated with the benign tumors. We believe that beta-6, tenascin-C, and MMP-1 proteins are part of the molecular repertoire used by salivary tumors for malignant invasion and benign tumor expansion

OBJECTIVES/HYPOTHESIS: To assess the value of both patient- and tumor-related factors of oropharyngeal squamous cell carcinoma in predicting patient outcome, with respect to the three primary subsites of the disease. It was hypothesized that the subsite has a significant impact on outcome. STUDY DESIGN: Historical cohort study. METHODS: A chart review was conducted of 126 patients diagnosed with squamous cell carcinoma of the oropharynx over a 10-year period. The oropharynx was divided into the following subsites: 1) base of tongue, 2) tonsil and pillars, and 3) uvula, soft palate, and posterior pharyngeal wall. Patient-related factors included age and gender. Tumor-related factors included American Joint Committee on Cancer stage, T stage, N stage, and grade. These factors were compared using the end points of disease-free survival and treatment response (complete response or partial response/no response). RESULTS: Tumor-related factors such as American Joint Committee on Cancer stage (P = .016) and T stage (P = .008) had a significant impact on treatment response. The American Joint Committee on Cancer stage (P = .030) and the T stage (P = .005) were also significant predictors of disease-free survival. Base-of-tongue lesions responded significantly worse to treatment than did tonsil and pillar or uvula, soft palate, and posterior pharyngeal wall lesions (P = .014). The disease-free survival for base-of-tongue cancer was significantly worse than for tonsil and pillar or for uvula, soft palate, and posterior pharyngeal wall cancer (P = .010). CONCLUSION: Patient-related factors such as age and gender were not significant in predicting disease-specific outcome. Important tumor-related factors were the American Joint Committee on Cancer stage and the T stage. Among the oropharyngeal subsites, squamous cell carcinoma of the base of tongue was associated with the worst outcome

The technique of endoscopic transnasal, nontransseptal, transsphenoidal pituitary surgery is gaining increasing popularity. Many pituitary surgical teams consider it the procedure of choice. It provides a rapid and safe approach to the sella turcica. Within the sella turcica, the endoscopes give the surgeon the ability to inspect around the corner and to remove residual tumor. The procedure avoids the complications related to the sublabial transeptal approach. Hospital stay is shorter

OBJECTIVE: To determine if age alone is a prognostic indicator of surgical outcomes for major head and neck procedures. DESIGN: Retrospective cohort study over a 4-year period. SETTING: Academic referral center, institutional practice, hospitalized care. PATIENTS: Included in this study were patients who had undergone ablative, reconstructive, and other major surgical procedures of the head and neck, including neck dissection, laryngectomy, maxillectomy, thyroidectomy with lymphadenectomy, and composite resection of the oral cavity with reconstruction, for both malignant and benign disease. MAIN OUTCOME MEASURES: Patient data and intraoperative and postoperative course factors were recorded. Comorbidity was graded using an Adult Comorbidity Evaluation 27 test, Charlson Comorbidity Index, and American Society of Anesthesiology score. Postoperative complications were dichotomized, and multiple logistic regression was used for data analysis. RESULTS: Medical chart review identified 157 cases. Analysis of data revealed that time under general anesthesia was the only factor consistently related to complications (P<.006), and it was the only factor consistently related to length of stay (P<.001). Analysis of major complications (6% incidence) as an outcome using univariate analysis resulted in a strong positive correlation with both comorbidity indexes: Adult Comorbidity Evaluation 27 (P = .002) and Charlson Comorbidity Index (P = .005). Multiple logistic regression showed no significant relationship between age 70 years or older (20% of patients) and either complications or hospital length of stay. CONCLUSIONS: Patient's age alone is not a prognostic indicator of surgical outcome for major head and neck procedures. However, comorbidity is an important predictive factor for postoperative complications in any age group. Time under general anesthesia showed a statistically significant relationship with complication rate and hospital length of stay in multivariate analyses. Consequently, prevention of complications should focus on optimizing preoperative comorbid conditions

Recurrent aphthous stomatitis (RAS) and recurrent oral herpes-including recurrent herpes labialis (RHL) and recurrent intraoral herpes (RIH)--are two of the most common oral ulcerative disorders. Despite their benign nature, both may be associated with pain, discomfort, and social avoidance. This article presents methods for dental professionals to diagnose and manage patients with these conditions