bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of the Auditory‐Evoked Brainstem Response Wave I to Distortion‐Product Otoacoustic Emissions Resulting From Changes to Inner Ear Blood Flow
Authors: Telischi Fred F. , Mom Thierry , Agrama Mark , Stagner Barden B. , Ozdamar Ozcan , Bustillo Andres , Martin Glen K. 
Published: November 2003

AbstractObjective/Hypothesis: Examine and compare in detail the time courses of the auditory brainstem response (ABR) wave I amplitude and latency to the distortion‐product otoacoustic emission (DPOAE) amplitude and phase measured in the rabbit model following deliberate obstruction of cochlear blood flow (CBF). Methods: Using a posterior fossa craniotomy in five rabbits, the internal auditory artery (IAA) was compressed with a probe. ABR and otoacoustic emission were continuously monitored before, during, and after the compressions. Results: ABR wave I amplitudes demonstrated measurable decreases at a mean of 28.3 s after IAA compression, whereas DPOAE amplitudes decreased after a mean of 14.8 s. Wave I latencies began to increase at a mean of 18.3 s after occlusion, while DPOAE phase measures changed after a mean of only 4.8 s following IAA compression. The time‐course patterns were similar for the amplitudes of both ABR wave I and DPOAE. Conclusions: ABR wave I amplitude follows a similar, though delayed (by approximately 10 s) time‐course pattern to that of the DPOAE following IAA compression. The implication of these findings for intraoperative auditory monitoring is that changes in many currently employed measures will lag actual surgically induced alterations in CBF by at least 20 to 30 s.
A Matched Control Study of Treatment Outcome in Young Patients With Squamous Cell Carcinoma of the Head and Neck
Authors: Verschuur Hendrik P. , Irish Jonathan C. , O'Sullivan Brian , Goh Christopher , Gullane Patrick J. , Pintilie Melania 
Published: November 2003

AbstractObjectives/Hypothesis: To determine if there is a difference in overall survival, cause‐specific survival, and relapse‐free rate between young patients (<40 years of age) with head and neck squamous cell carcinoma (HNSCC) and older patients (>40 years of age). Study design: A matched control study describing the outcome of 185 previously untreated HNSCC patients less than 40 years of age treated at the Princess Margaret Hospital, Toronto, Ontario, Canada, between 1958 and 1992. The young patient group was compared with a control group of older patients (> 40 years of age) which was selected randomly from an entire cohort of patients (n = 10,072) and matched for site, sex, and date of presentation. Methods: The medical records were reviewed and data abstracted for demographic information, tobacco and alcohol use, family history, primary site, clinical stage, primary treatment, histology, the occurrence of residual or recurrent disease, salvage treatment, development of subsequent primaries, survival, and the eventual cause of death. The patient's TNM stage was reclassified according to American Joint Cancer Committee/Union Internationale Contre le Cancer (AJCC/UICC) 1992 criteria on the basis of the initial clinical description and staging investigations. A multivariate regression analysis was performed. To assess the importance of age as a prognostic factor for survival, the Cox proportion hazard model was used. Smoking status was also tested in the stratified Cox proportional hazard model. Results: Tumor stage and treatment modalities were comparable in both groups. The 5‐year, cause‐specific survival in both groups was not statistically different (72% vs. 68%, P = .91). The young patient group had a significantly better 5‐year overall survival compared with the older patient group (68% vs. 49%, P = .0011). Older patients developed more subsequent primary neoplasms than the younger patient population (18% vs. 8%, P = .005). There were significantly more females, an increased incidence of oral or oropharyngeal cancer, and fewer smokers in the young patient group. Smoking, however, had an important impact on outcome with all but one patient who developed a second primary in the upper aerodigestive tract having smoked. Multivariate analysis showed that only disease stage and cancer site were significant prognostic factors for survival. Conclusions: Young patients with HNSCC do not have a worse prognosis than a matched older patient group in this case‐controlled study (power > 0.75 for a minimal detectable difference of 10% disease‐free survival between the two groups).
Illness and Otological Changes During Upper Respiratory Virus Infection
Authors: Doyle William J. , Alper Cuneyt M. , Buchman Craig A. , Moody Stephanie A. , Skoner David P. , Cohen Sheldon 
Published: November 2003

AbstractObjectives: Upper respiratory virus infection is associated with the expression of symptoms and signs of illness, and with the development of complications in anatomically contiguous structures. In most epidemiological studies, the frequency of the various complications is expressed as a fraction of the total population judged to be ill by report, signs, or symptoms. Because not all infected subjects become ill and because infected non‐ill subjects may develop complications, such risk estimates could be inaccurate. The objective of this study was to estimate the magnitude of the presentation bias during controlled, experimental infections. Study Design: This was a prospective, experimental study of the relationship between illness and otological complications during experimental upper respiratory virus infection in 316 adult volunteers. Methods: The data for illness and for abnormal middle ear underpressure in adult (18–54 y) volunteers experimentally infected with one of three viruses (rhinovirus type 39, rhinovirus strain hanks, influenza A virus) were analyzed and expressed as the relative frequencies of infected subjects reporting illness, developing abnormal middle ear pressure, and developing abnormal middle ear pressure in the absence of illness. Results: For all three viruses, illness was documented in approximately 50% of the infected subjects. While the frequency of persons developing abnormal middle ear underpressure was greater in the infected‐ill subjects, approximately one third of all infected subjects developing that complication did not report illness. Conclusions: These results support a large presentation bias in epidemiological surveys of viral upper respiratory infections, and infer that those surveys underestimate the true frequency of complications resulting from such infections.
Expression of γ‐Aminobutyric AcidA Receptor Subunits in the Vestibular System
Authors: Rezaee Ali , Robinson Alan M. , Pitovski Dimitri Z. 
Published: November 2003

AbstractObjectives: Profile the expression of genes encoding GABAA receptor subunits in the vestibular end organs of a rat. Materials and Methods: Using a combination of reverse transcription followed by polymerase chain reaction (PCR) with gene‐specific primers, expression of mRNAs encoding 13 individual GABAAA receptor subunits was examined. Results: PCR amplification products representing subunit gene expression for α1–6, β‐3, and γ1–3, but not for δ, sub‐units were amplified, suggesting multiple molecular levels of regulation of vestibular GABAA receptor expression. Nucleotide sequencing confirmed the identity of rat vestibular end‐organs subunit cDNAs. Conclusion: These results give the most direct evidence to date that GABAA receptors composed of the detected subunits are expressed in the mammalian vestibular system, giving new support to previous investigations implicating GABA as a vestibular neurotransmitter.
Streptomycin ototoxicity and hair cell regeneration in the adult pigeon utricle
Authors: Frank Thomas C. , Dye Bradford J. , Newlands Shawn D. , Dickman J. David 
Published: November 2003

AbstractObjective: The purpose of this study was to develop a technique to investigate the regeneration of utricular hair cells in the adult pigeon (Columba livia) following complete hair cell loss through administration of streptomycin. Study Design: Experimental animal study. Methods: Animals were divided into four groups. Group 1 received 10 to 15 days of systemic streptomycin injections. Animals in Groups 2 and 3 received a single direct placement of a 1‐, 2‐, 4‐, or 8‐mg streptomycin dose into the perilymphatic space. Animals in Groups 1 and 2 were analyzed within 1 week from injection to investigate hair cell destruction, whereas Group 3 was investigated at later dates to study hair cell recovery. Group 4 animals received a control injection of saline into the perilymphatic space. Damage and recovery were quantified by counting hair cells in isolated utricles using scanning electron microscopy. Results: Although systemic injections failed to reliably achieve complete utricular hair cell destruction, a single direct placement of a 2‐, 4‐, or 8‐mg streptomycin dose caused complete destruction within the first week. Incomplete hair cell loss was observed with the 1‐mg dose. Over the long term, regeneration of the hair cells was seen with the 2‐mg dose but not the 8‐mg dose. Control injections of saline into the perilymphatic space caused no measurable hair cell loss. Conclusions: Direct placement of streptomycin into the perilymph is an effective, reliable method for complete destruction of utricular hair cells while preserving the regenerative potential of the neuroepithelium.
Nasal alar reconstruction: A critical analysis using melolabial island and paramedian forehead flaps
Authors: Arden Richard L. , Nawroz‐Danish Myra , Yoo George H. , Meleca Robert J. , Burgio Don L. 
Published: November 2003

AbstractObjectives: To qualitatively and quantitatively describe aesthetic and functional outcomes following Mohs ablative surgery involving the alar subunit, using a paramedian or subcutaneous melolabial island flap. Study Design: Retrospective review. Methods: A single surgeon's results in 38 consecutive patients were analyzed. Objective measures (alar rim thickness, donor scar width and length), subjective assessment (seven aesthetic parameters) by three academic otolaryngologists, and patient satisfaction questionnaires were evaluated. Student t test was used to ascertain statistically significant differences between reconstructive groups. Results: Questionnaire results demonstrate a significant (P = .026) difference in donor site rating favoring melolabial group responses. Objective scar measurements and subjective ratings of textural quality and alar notching also favored melolabial reconstructions. Conclusions: More favorable aesthetic and functional outcomes are seen with single subunit cutaneous alar defects reconstructed with the melolabial island flap than with deep composite or extensive unilateral nasal defects reconstructed with the paramedian forehead flap.
Auricular Rehabilitation With Bone‐Anchored Titanium Implants
Authors: Wazen Jack J. , Wright Robert , Hatfield Regina B. , Asher Eric S. 
Published: November 2003

AbstractObjective: To evaluate the effectiveness of the bone‐anchored titanium implants in auricular reconstructions.Study Design: Six patients who received implants for an auricular reconstruction were followed prospectively. Four patients had lost their ears to cancer, and the other two had congenital aural atresia.Methods: All patients were thoroughly evaluated by the reconstruction team, which included a surgeon, a prosthodontist, and a facial prosthetist. Three patients were evaluated audiologically for a bone‐anchored hearing aid. Four patients received implants in a single‐stage procedure, and two underwent a two‐stage procedure. A gold bar with retaining clips was used to anchor the prosthetic ear in four patients, and magnets were used in the remaining two.Results: All six patients are completely satisfied with their reconstructions. No failures, extrusions, or bony complications were encountered. One patient had recurrent dermatitis, which subsided when his gold bar was replaced with magnets.Conclusion: Implanted under the guidance of an appropriate prosthetic team, bone‐anchored titanium implants provide patients with a safe, reliable, adhesive‐free method to anchor auricular prostheses with recovery of their normal appearance.
Th‐2 Type Cytokine Receptors in Allergic Rhinitis and in Response to Topical Steroids
Authors: Wright Erin D. , Christodoulopoulos Pota , Small Peter , Frenkiel Saul , Hamid Qutayba 
Published: November 2003

AbstractObjectives: Th‐2 type cytokine production (Interleukin‐4 [IL‐4] and interleukin‐5 [IL‐5]) has been demonstrated to play a significant role in the pathophysiology of allergic rhinitis (AR), and the treatment of AR with topical corticosteroids has been shown to reduce the expression of Th‐2 type cytokines in vivo. However, the contribution and expression of Th‐2 type cytokine receptors in AR and their response to corticosteroid treatment remain to be clarified. Objectives of the current study are 1. To examine the expression of the cytokine IL‐4 and IL‐5 receptors (IL‐4R and IL‐5R) in a nasal allergen challenge model and to contrast this with the expression of the receptor for the Th‐1 type cytokine, interferon‐gamma receptor (IFN‐γR), and 2. to examine the effects of pretreatment with topical corticosteroid before allergen challenge on the expression of these same receptors.Study Design: Randomized prospective study involving 14 ragweed‐allergic subjects evenly divided between placebo and corticosteroid pretreatment.Methods: Immunocytochemistry (alkaline phosphatase‐antialkaline phosphatase labeling [APAAP] technique) was used to stain nasal biopsy specimens before and after allergen challenge. Antibodies used included anti‐CD3, CD4, CD8, major basic protein (MBP), IL‐4R, IL‐5R, and IFN‐γR.Results: Following allergen challenge, we observed a significant increase in the Th‐2 type cytokine receptors (IL‐4R and IL‐5R; P < .05), as well as a significant decrease in the expression of the Th‐1 type cytokine receptor (IFN‐γR; P < .05). Pretreatment with topical corticosteroids before nasal allergen challenge resulted in decreased expression of IL‐4R (P < .05) and IL‐4R (P < .05) and increased expression of IFN‐γR (P < .05). Further, IL‐4R and IL‐5R expression correlated with eosinophil infiltration in the tissues.Conclusions: We have demonstrated that in AR, cytokine receptors for IL‐4, IL‐5, and IFN‐γ follow a similar pattern to their ligands. In addition, pretreatment with topical corticosteroids was shown to alter the cytokine receptor expression pattern from a Th‐2 profile more toward a Th‐1 profile.
Microvasculature, Blood Flow, and Vasoreactivity in Rabbit Sinus Mucosa After Surgery
Authors: Forsgren Karin , Otori Nobuyoshi , Stierna Pontus , Kumlien Jan 
Published: November 2003

AbstractObjectives: To study the circulatory integrity of the sinus mucosa following surgery, the vascular anatomy, blood flow, and vasoconstrictor response of the regenerated microcirculatory network were analyzed.Study Design: Forty‐six New Zealand White rabbits were operated on unilaterally with either a modified radical operation (MRO) or middle meatal antrostomy (MMA), using the nonoperated sinus for control purposes. After surgery, the animals were left to heal for 1 month.Methods: Vascular casts were prepared with a low‐viscosity methyl methacrylate resin and studied by scanning electron microscopy. Blood flow was measured by means of radiolabeled microspheres (tin 113 [113Sn]). The vasoconstrictor response to oxymetazoline at increasing concentrations was measured with laser Doppler flowmetry.Results: The number of vessels increased significantly in the regenerated mucosa. The vascular casts displayed a rich microcirculation with local signs of angiogenesis. However, there was no difference in blood flow between the operated cavities and their control sides. Following MRO the regenerated mucosa was more sensitive to the vasoconstrictor effect of oxymetazoline, compared with the control side. This difference was not evident in the MMA‐operated sinuses.Conclusions: In this model, surgery does not seriously interfere with the sinus blood flow, although the regenerated mucosa did display an altered vasoreactivity. These findings should be considered in relation to the effects of surgery intended to limit local inflammation and to ensure the ventilation of the sinuses.
Reconstruction of the Ossicular Chain in the Middle Ear With Glass Ionomer Cement
Authors: Brask Torben 
Published: November 2003

AbstractObjectives: The aim of this study is to describe a method to repair small defects (1 to 2 mm) of the ossicular chain by means of glass ionomer cement (GIC) alone. Larger defects can be repaired with a combination of GIC and a platinum wire prosthesis. GIC is a two‐component hybrid material consisting of inorganic glass particles surrounded by an insoluble hydrogel matrix. GIC has been used by dentists for many years, but only a few reports describe the use of GIC in human middle ear surgery. Many investigators have proved that most GICs are biocompatible, biostable, and well tolerated by bone and soft tissue.Study Design: From 1994 to 1996 GIC was used in 97 middle ear operations. In 44 cases small defects of the ossicular chain were reconstructed with GIC alone. The observation period ranged from 1 to 4 years.Methods: Nearly all operations were performed with the patient under local analgesia.Results: The postoperative air‐bone gap was less than 20 dB in 83.3%. Compared with results from comparable operations, the GIC results are significantly better. One patient had reoperation because the cement had loosened from the bone as a result of faulty GIC operation technique.Conclusions: Repair of defects of the ossicular chain with GIC is an easy, efficient, quick, and inexpensive method, which ought to be kept in mind for future middle ear surgery. No complications in the middle ear were related to GIC.
Localization of Static Positional Nystagmus With the Ocular Fixation Test
Authors: Maire Raphael , Duvoisin Bertrand 
Published: November 2003

AbstractObjective: Characteristics of static positional nystagmus (SPN) (i.e., persistency, direction fixed, direction changing) are observed in both peripheral and central disturbances and possess no localizing value for vestibular lesions. Our objective was to investigate whether the ocular fixation test as applied to SPN could assist in localizing vestibular lesions.Study Design: A 3‐year prospective study that included 43 patients with SPN.Methods: All patients underwent a standard vestibular test battery and cerebral imaging (7, computed tomography scan; 36, magnetic resonance imaging). The ocular fixation index (OFI) was calculated by the ratio of the mean slow component velocity of SPN (measured with red light‐emitting diode fixation) to that measured in darkness, multiplied by 100. An OFI less than 50 was considered normal.Results: In 33 of 35 patients whose OFI was less than 50, the cerebral imaging was normal and a peripheral vestibular lesion was diagnosed (two benign tumors of the fourth ventricle were missed). In all eight patients whose OFI was greater than 50, the cerebral imaging was abnormal and a central vestibular lesion was noted.Conclusions: These results indicate that the visual suppression of SPN does, indeed, permit the localization of vestibular lesions. The predictive value of the ocular fixation test on the origin of SPN is greater than 94% for peripheral lesions and 100% for central disorders.
Expression of Fas/APO‐1 and Apoptosis of Keratinocytes in Human Cholesteatoma
Authors: Park Hong‐Joon , Park Keehyun 
Published: November 2003

AbstractObjectives: The Fas/APO‐1 is a cell surface receptor protein known to trigger apoptosis when conjugated with Fas ligand or specific agonistic antibodies. The present study investigated the expression of Fas/APO‐1 and apoptotic cell death in both normal and cholesteatoma epithelia.Study Design: Ten cholesteatomas and retroauricular skins were taken during middle ear operations in the Ajou University Hospital for this study.Methods: In situ terminal deoxynucleotidyl transferase (TdT)‐mediated dUTP nick end‐labeling (TUNEL) staining and agarose gel electrophoresis of genomic DNA were used for detection of apoptosis. The expression patterns of Fas/APO‐1 protein were confirmed by immunoblot and immunohistochemical analysis.Results: In situ TUNEL staining revealed many positively stained nuclei in 9 of 10 suprabasal layers of cholesteatoma epithelium, whereas few positively stained cells were found on the granular layer of retroauricular skins. Typical “ladder pattern” was seen on the gel electrophoresis of the genomic DNA of cholesteatoma. Immunoblot analysis and immunohistochemical studies revealed that Fas/APO‐1 protein was expressed in 8 of 10 cholesteatoma epithelia, whereas retroauricular skin showed negative reaction.Conclusion: These results show the upregulated expression of Fas/APO‐1 and increased apoptotic cell death in cholesteatoma epithelium. Because Fas/APO‐1 is known as an apoptosis‐triggering protein, it is suggested that the accumulation of keratin debris is due to increased apoptotic cell death related to Fas/APO‐1 protein.
Mutational Analyses of Candidate Genes in Human Squamous Cell Carcinomas
Authors: Petroianu Andy , Boson Wolfanga L. , Bale Allen E. , Friedman Eitan , De Marco Luiz 
Published: November 2003

AbstractObjectives and Study Design: Squamous cell carcinomas are common malignancies and a major cause of mortality. The molecular mechanisms involved in tumorigenesis remain largely unknown, but sequence alterations have been identified in coding regions of several genes. Primary squamous cell carcinomas of various tissues (skin, head and neck, esophagus, lung, penis, uterus, and vagina) from 52 patients were analyzed for the presence of mutations within several candidate genes presumably involved in tumorigenesis: Gsα, Gi2α, GTPase activating protein (GAP), and patched (PTCH) genes.Methods: Mutational analysis scheme included polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), single stranded conformational polymorphism (SSCP), and selected sequence analysis.Results and Conclusion: No tumor had any evidence of mutations in any of these analyzed genes. Mutations within these genes do not occur frequently in an unselected population of patients with squamous cell carcinomas.