bluuebunny/crossref_metadata_2025 huggingface dataset:
Podoplanin binds ERM proteins to activate RhoA and promote epithelial-mesenchymal transition
Authors: Martín-Villar Ester , Megías Diego , Castel Susanna , Yurrita Maria Marta , Vilaró Senén , Quintanilla Miguel
Published: October 2006

Podoplanin is a small membrane mucin expressed in tumors associated with malignant progression. It is enriched at cell-surface protrusions where it colocalizes with members of the ERM (ezrin, radixin, moesin) protein family. Here, we found that human podoplanin directly interacts with ezrin (and moesin) in vitro and in vivo through a cluster of basic amino acids within its cytoplasmic tail, mainly through a juxtamembrane dipeptide RK. Podoplanin induced an epithelial-mesenchymal transition in MDCK cells linked to the activation of RhoA and increased cell migration and invasiveness. Fluorescence time-lapse video observations in migrating cells indicate that podoplanin might be involved in ruffling activity as well as in retractive processes. By using mutant podoplanin constructs fused to green fluorescent protein we show that association of the cytoplasmic tail with ERM proteins is required for upregulation of RhoA activity and epithelial-mesenchymal transition. Furthermore, expression of either a dominant-negative truncated variant of ezrin or a dominant-negative mutant form of RhoA blocked podoplanin-induced RhoA activation and epithelial-mesenchymal transition. These results provide a mechanistic basis to understand the role of podoplanin in cell migration or invasiveness.
Interactions between the human gastrocnemius muscle and the Achilles tendon during incline, level and decline locomotion
Authors: Lichtwark G. A. , Wilson A. M.
Published: October 2006

Muscles are required to perform or absorb mechanical work under different conditions. However the ability of a muscle to do this depends on the interaction between its contractile components and its elastic components. In the present study we have used ultrasound to examine the length changes of the gastrocnemius medialis muscle fascicle along with those of the elastic Achilles tendon during locomotion under different incline conditions. Six male participants walked (at 5 km h-1) on a treadmill at grades of -10%,0% and 10% and ran (at 10 km h-1) at grades of 0% and 10%, whilst simultaneous ultrasound, electromyography and kinematics were recorded. In both walking and running, force was developed isometrically; however,increases in incline increased the muscle fascicle length at which force was developed. Force was developed at shorter muscle lengths for running when compared to walking. Substantial levels of Achilles tendon strain were recorded in both walking and running conditions, which allowed the muscle fascicles to act at speeds more favourable for power production. In all conditions, positive work was performed by the muscle. The measurements suggest that there is very little change in the function of the muscle fascicles at different slopes or speeds, despite changes in the required external work. This may be a consequence of the role of this biarticular muscle or of the load sharing between the other muscles of the triceps surae.
Electrophysiological evidence for linear polarization sensitivity in the compound eyes of the stomatopod crustacean Gonodactylus chiragra
Authors: Kleinlogel Sonja , Marshall N. Justin
Published: October 2006

Gonodactyloid stomatopod crustaceans possess polarization vision, which enables them to discriminate light of different e-vector angle. Their unusual apposition compound eyes are divided by an equatorial band of six rows of enlarged, structurally modified ommatidia, the mid-band (MB). The rhabdoms of the two most ventral MB rows 5 and 6 are structurally designed for polarization vision. Here we show, with electrophysiological recordings, that the photoreceptors R1-R7 within these two MB rows in Gonodactylus chiragra are highly sensitive to linear polarized light of two orthogonal directions (PS=6.1). They possess a narrow spectral sensitivity peaking at 565 nm. Unexpectedly, photoreceptors within the distal rhabdomal tier of MB row 2 also possess highly sensitive linear polarization receptors, which are in their spectral and polarization characteristics similar to the receptors of MB rows 5 and 6. Photoreceptors R1-R7 within the remainder of the MB exhibit low polarization sensitivity (PS=2.3). Outside the MB, in the two hemispheres,R1-R7 possess medium linear polarization sensitivity (PS=3.8) and a broad spectral sensitivity peaking at around 500 nm, typical for most crustaceans. Throughout the retina the most distally situated UV-sensitive R8 cells are not sensitive to linear polarized light.
Study of aero-engine oil-air separators
Authors: Eastwick C. N. , Simmons K , Wang Y , Hibberd S
Published: October 2006

For aero-engines, oil-air separation is a key function, and one approach to assessing separator effectiveness is computational fluid dynamics (CFD). The two-phase flow is complex and oil can be present in different forms (for example, droplets, mist, film). However, necessary modelling simplifications may affect solution accuracy and range of validity. This article presents a modelling methodology for oil-air separators; the effect of simplifications is discussed and their relative magnitude assessed. Comparison with available experimental data is presented. It is concluded that although simplification has an impact, the significant features of the oil-air separator are predicted with sufficient accuracy to allow design comparisons.

Two separator configurations, one internal to a bearing chamber and one external, are modelled and the data presented. Flow fields are compared and the effectiveness of the separators in removing oil droplets prior to impact on the breather (primary separation) presented. The separation performance of the external design is largely independent of shaft speed, with all droplets >3 μm removed before impact on the breather. The critical droplet diameter of the internal design is larger, varying with breather configuration and shaft speed but the power loss is an order of magnitude lower than for the external design.
Using swirl flow to improve efficiency of flares
Authors: Ali A A K. Mohammed , Jassim R. K.
Published: October 2006

The products of the gaseous form hydrocarbon process and large quantities of condensate or waste gases that can be evolved from oil and natural gas fields or oil refineries, must be discharged to the atmosphere after being burnt using flares. The flaring of these waste gases is the most expedient way of obviating possible dangers from clouds of toxic vapours or pockets of explosive gases. The problem of flares being blown off by cross-wind is producing a high level of environmental pollution. Therefore, there is a need to reduce the environmental pollution (including ‘flaming rain’, a phenomenon of a shower downwind of oil droplets after the flare is blown off). The proposed solution is to stabilize the flare by using a swirl technology. A prototype flare burner was designed and tested using a mixture of natural gas (methane) and diesel fuel to simulate the condensate, and a number of nozzles were also tested to improve the atomization process of fuel. The use of swirl tends to have a mixing between air and fuel, and then produces a high level of turbulence that leads to a good flame stabilization. The results show an improvement in the combustion efficiency and low level of pollution as a result of a well-stirred region within the flame.
Optimizing impeller geometry for performance enhancement of a centrifugal pump using the Taguchi quality concept
Authors: Nataraj M , Arunachalam V. P.
Published: October 2006

This article discusses a research methodology for performance enhancement of centrifugal pump through Taguchi's parametric design concept. The objective is to find an optimum impeller design and geometry that makes the pump functionally reliable for winning customer's confidence. Computational fluid dynamic (CFD) analysis has been done to know how the flow pattern changes in the impeller when the pump is required to run at different operating conditions. The streamline analysis from CFD plots gives informative pictures of the flow field, which help the designer understand how the effect of deviation made in the impeller design specifications significantly influence the pump performance. CFD results match well with the predictions of the pump performance at the duty point as regard to head, discharge, and efficiency of the prototype model. The study infers that the CFD prediction tallies with Taguchi's experimental results.
Two-dimensional analysis of cavitating flows in a centrifugal pump using a single-phase Reynolds averaged Navier—Stokes solver and cavitation model
Authors: Li J , Liu L-J , Feng Z-P
Published: October 2006

A newly developed cavitation model and algorithm for predicting hydrodynamic performance of a centrifugal pump under cavitating condition is presented. The cavitation model is implemented in a Reynolds-averaged Navier—Stokes flow solver with turbulence model employed. A priori knowledge of the wall detachment point and bubble length is not required, but naturally a part of the solution by this cavitation model. The liquid/vapour interface is tracked and obtained by an iteration procedure between the flow field computation and the interface updating. The capability to capture some important phenomena of cavitation flows in a centrifugal pump impeller is shown by the cavitation prediction. The numerical results also show that the cavity size increases dramatically with the decrease in the cavitation number and so does the loss of the head rise.
Effects of blade sweep on the performance characteristics of axial flow turbomachinery rotors
Authors: Vad J , Kwedikha A. R A. , Jaberg H
Published: October 2006

Experimental studies were carried out in order to survey the performance and efficiency aspects of spanwise constant forward and backward sweep in axial flow rotors of low aspect ratio (AR) blading for incompressible flow, for part-load, near-design, and overload operational ranges. The experiments involved overall performance tests, laser Doppler velocimetry, and stationary total pressure probe measurements. The overall performance data and pitchwise averaged and resolved flow characteristics were evaluated in detail. For moderate and high flow rates, it was pointed out that positive or negative sweep tends to reduce or increase the blade load in the vicinity of the endwalls, respectively. It has been concluded that the loss-modifying effect of sweep can be judged by considering the three-dimensional viscous phenomena, and the influence of sweep on local blade efficiency depends on the balance of changes in blade load and losses. For low flow rates, forward sweep was found beneficial over the entire span from the aspect of improved stall margin and efficiency. The influence of AR on the performance reducing effect of sweep was studied on the basis of literature data.
Destruction of availability (exergy) due to combustion processes: A parametric study
Authors: Chavannavar P. S. , Caton J. A.
Published: October 2006

An analytical examination of the destruction of availability was completed for constant pressure, constant volume, and constant temperature combustion processes for isooctane vapour and air mixtures. The variation of the percentage destruction of availability was determined as a function of temperature, pressure, and equivalence ratio. The percentage destruction of availability decreased with increasing reactant temperatures (from ∼30 per cent at 300 K to ∼5 per cent at 4500 K for constant pressure and constant volume combustion processes). The effect of the reactant pressure on the percentage availability destroyed was less pronounced - for example, for a 500 K initial temperature, a change from 50 to 5000 kPa changed the percentage availability destroyed from 26 per cent to 22 per cent for constant pressure adiabatic combustion. For changes in the equivalence ratio, the lowest destruction of availability was for mixtures near stoichiometric. In addition, the contribution of the various components (e.g. chemical and thermo-mechanical) of the mixture availability to the total availability was quantified for a range of conditions. Also, the effect of the decomposition of the reactant species for high reactant temperatures (greater than 3000 K) was determined.
Investigation of the energetic and exergetic performance of the Gonen geothermal district heating system
Authors: Ozgener L , Hepbasli A , Dincer I
Published: October 2006

This article describes a performance evaluation of the Gonen geothermal district heating system (GGDHS) in Balikesir, Turkey on the basis of energy and exergy analyses. The case study covers the actual system data taken from the GGDHS in Balikesir, Turkey. General energy and exergy analyses of the geothermal district heating systems are introduced. Then, these analyses applied to the GGDHS using actual thermodynamic data for its performance evaluation in terms of energy and exergy efficiencies are presented. In addition, a parametric study on the effect of varying reference state properties on the energy and exergy efficiencies of the system that has been conducted to find the optimum performance and operating conditions is explained. In this article, the authors undertake a parametric study to investigate how varying reference temperature from 0°C to 20°C will affect the energy and exergy efficiencies of the GGDHS and develop two significant correlations (with a correlation coefficient of 0.99), which can be used for predicting the efficiencies. Two parametric expressions for energy and exergy efficiencies were developed as a function of the reference temperature. Both energy and exergy flow diagrams illustrate and compare the results under different conditions. For the actual system that is presented, the system energy and exergy efficiencies vary between 0.41 and 0.60 and 0.60 and 0.70, respectively.
Energy and carbon audit of a rooftop wind turbine
Authors: Rankine R. K. , Chick J. P. , Harrison G. P.
Published: October 2006

Microgeneration is being promoted as a means of lowering carbon dioxide (CO2) emissions by replacing electricity from the grid with production from small domestic generators. One concern over this drive is that the use of smaller plant could lead to the loss of economies of scale. Partly, this relates to cost but also in terms of energy consumed and CO2 emitted over the life cycle of the microgenerator.

Here, an analysis is presented of a life-cycle audit of the energy use and CO2 emissions for the ‘SWIFT’, a 1.5 kW rooftop-mounted, grid-connected wind turbine. The analysis shows that per kilowatt-hour of electricity generated by the turbine, the energy intensity and CO2 emissions are comparable with larger wind turbines and significantly lower than fossil-fuelled generation. With energy and carbon intensities sensitive to assumed levels of production, assessments were carried out for an annual production range of 1000–4000 kWh, representing capacity factors of 8–31 per cent. For the manufacturer's estimated production of 2000 to 3000 kWh and, giving credit for component recycling, the energy payback period was found to be between 17 and 25 months, whereas the CO2 payback was between 13 and 20 months. Across the full production range, the energy and carbon payback periods were 13–50 months and 10–39 months, respectively.

A key outcome of the study is to inform the manufacturer of the opportunities for improving the energy and carbon intensities of the turbine. A simple example is presented showing the impact of replacing one of the larger aluminium components with alternative materials.
Forced response of electromechanical-integrated toroidal drive to load and voltage excitations
Authors: Xu L , Hao X , Wang H
Published: October 2006

In this article, on the basis of results for mode analysis, the forced vibration of the drive system to load and voltage excitations is investigated. By dividing load, displacement, voltage, and current into mean values and time-varying ones, the dynamic equations of the mechanical and electrical systems are transformed into the ones for time-varying portion of the displacements or current, respectively. Using the Laplace transformation, the transfer functions of the mechanical and electrical systems are obtained. The transfer functions are used in the study to investigate the forced frequency responses of the mechanical and electrical systems to the load or voltage excitations. The influences of the drive parameters on the forced responses are discussed in detail. It is known that only for the three natural frequencies of the rotational modes, the forced responses of the mechanical system to load excitations occur. In addition, the results are used to simplify the dynamic equations of the mechanical system, and three-degree-of-freedom motion equations of the mechanical system are obtained. Results show that electrical parameters have significant influence on the vibration of the mechanical system and vice versa.
Some characteristics of rolling-element bearings under oscillating conditions. Part 3: Experimental results for clearance-fitted taper-roller bearings and their relevance to the design of spindles with high dynamic stiffness
Authors: Lambert R J , Pollard A , Stone B J
Published: October 2006

Some characteristics are presented for taper-roller bearings with a clearance fit. The stiffness and damping in the joints between raceways and housing/shaft are shown to be significant. The other major parameters investigated are preload, temperature, lubricant viscosity, excitation frequency, excitation amplitude, and rotational speed. The relevance of the measured characteristics to the design of spindles with high dynamic stiffness is discussed. Also the significance of radial and tilt characteristics is compared.
Some characteristics of rolling-element bearings under oscillating conditions. Part 1: Theory and rig design
Authors: Lambert R J , Pollard A , Stone B J
Published: October 2006

Rolling-element bearings are among the most common components of modern machinery and yet little is known about their characteristics under working and oscillating conditions. Thus, when spindle systems are designed and their dynamic stiffness is important, it is very difficult to find suitable characteristics to use in the modelling. It is the purpose of this paper to indicate why these characteristics are difficult to measure and to discuss the results that are available in the literature. It is also the case that very few models have been developed to represent the stiffness and damping of rolling-element bearings. In the 1980s, some models were developed, but these were in confidential, limited-circulation publications. However, permission has now been given to present these models in the open literature. The principles of a rig are described that allow the stiffness and damping properties of rolling-element bearings to be measured under rotating conditions. A theoretical analysis is presented that allows the characteristics of the rolling contacts to be predicted. In addition, the effect of the necessary joints that arise when using bearings is analysed. A detailed description is given of the rig and its initial calibration and testing. The extensive results obtained are described in parts 2 and 3 of this work.
Some characteristics of rolling-element bearings under oscillating conditions. Part 2: Experimental results for interference-fitted taper-roller bearings
Authors: Lambert R J , Pollard A , Stone B J
Published: October 2006

Some stiffness and damping characteristics are presented for taper-roller bearings with interference fits. The major parameters investigated were preload, temperature, lubricant viscosity, excitation frequency, excitation amplitude, and rotational speed. The prediction, based on a model of the bearings, that stiffness and damping would effectively be independent of oil viscosity was confirmed.
Realtime telemedicine
Authors: Wootton Richard
Published: October 2006

Telemedicine conducted via prerecorded interaction is more convenient than that using realtime interaction. On the other hand, a realtime consultation allows an immediate result to be obtained and there is likely to be a strong educational component for the remote practitioner. The use of the telephone is under-rated in telemedicine. Telephones have been used in outpatient follow-up, mental health, help lines and support groups. Telephones (fixed and mobile) have also been used for data transfer (e.g. for transmission of electrocardiograms). Realtime transfer of still images has been used in telepathology for many years, and more recently for rapid assessment of injuries. Realtime transfer of video images has been widely explored, perhaps most successfully in telepsychiatry. Some realtime telemedicine applications have been taken up with enthusiasm, even if formal evidence of cost-effectiveness may be lacking. Teleradiology and telepsychiatry are two examples where widespread adoption is beginning to occur. Other forms of realtime telemedicine represent 'niche' applications. That is, they appear to be both successful and sustainable in the centres where they were pioneered, but have not been adopted elsewhere. Teledialysis and teleoncology are examples of this type. The patchy diffusion of telemedicine is something that is not yet well understood.
Studies in tympanometry: Validation of the present technique for determining intra‐tympanic pressures through the intact eardrum
Authors: Eliachar Isaac , Northern Jerry L.
Published: October 2006

A simple technique designed to relate controlled changes in middle ear pressures brought about in the pressure chamber with simultaneously measured tympanometric recordings was used to validate the electroacoustic impedance assessment of intratympanic air pressures in human beings.

The data obtained showed the absolute and tympanometric results to be in close approximation. Tympanometry in its capacity of evaluating Eustachian tube functions, was classified into two versions: the static type, which records the consequent results of Eustachian tube functions or malfunction, together with a graphic estimation of the overall tympanic membrane compliance; and the dynamic type, that actually records and assesses Eustachian functions quantitatively. The contribution of this work toward further understanding and usage of tympanometry in clinical practice is briefly discussed in view of the proven validity and reliability of the test.
Actinomycosis of the tympanomastoid
Authors: Leek Joseph H.
Published: October 2006

An informational survey about actinomycosis is presented. Following this review, the case reports of two patients with actinomycosis of the tympanomastoid are discussed in detail.

The bizarre clinical course and the unusual gross pathological findings during surgery should alert the otologist to consider actinomycosis as the etiologic entity. Effective treatment combines surgery and long‐term chemotherapy.
The significance of positive margins in hemilaryngectomy specimens.
Authors: Bauer W. C. , Lesinski S. G. , Ogura J. H.
Published: October 2006

This clinicopathologic study was undertaken to determine the meaning of surgical margins “involved” with carcinoma. The fate of hemilaryngectomy patients whose specimens had this finding was compared with that of patients who had “uninvolved” margins.

A consecutive series of 111 hemilaryngectomies performed for previously untreated invasive epidermoid carcinoma was analyzed. Serial step sections in a longitudinal plane were available for re‐examination and re‐evaluation of the surgical margins in each case. Clinical follow‐up on every patient was current through 1972.

Thirty‐nine patients had cancer involvement of a margin in the hemilaryngectomy specimen. None of these patients received any immediate therapy but were followed only. Seven of these patients (18 percent) subsequently developed a biopsy proven local recurrence. Four of the 72 patients (6 percent) with uninvolved margins developed a local recurrence. The site of the positive margin in the specimen was compared with the clinical site of recurrence.

The seven local recurrences in patients with positive margins were treated with full course irradiation or total laryngectomy. All of these patients are alive and free of cancer or have died of other causes without evidence of cancer. Of the four local recurrences in patients with negative margins one died of cancer; two are living and well, and one died of other causes.

This study provides evidence to support the conservative management of those hemilaryngectomy patients who have involved margins in the resection specimen. No immediate treatment is required. Careful follow‐up is indicated with 18 percent chance of clinical recurrence. These biopsy proven recurrences can then be successfully treated with total laryngectomy or full course irradiation.

Utilizing this approach none of the 39 patients with involved margins died of cancer in the 5 to 12‐year follow‐up period.
Optimal treatment for the technically resectable squamous cell carcinoma of the supraglottic larynx.
Authors: Goepfert Helmuth , Jesse Richard H. , Fletcher Gilbert H. , Hamberger Arthur
Published: October 2006

The charts of 431 patients with squamous cell carcinoma of the supraglottic larynx observed at the M. D. Anderson Hospital between January, 1954, and June, 1971, were analyzed. This study is concerned with those patients who had a technically resectable lesion. Emphasis is directed to the analysis of the effectiveness of primary irradiation instead of partial laryngectomy for those lesions which are technically suitable for a partial resection and to define the groups of patients which are best treated by combining surgery and planned postoperative irradiation.

One hundred forty‐seven patients with T1 and T2 lesions, selected exophytic T3 lesions of the suprahyoid epiglottis and aryepiglottic folds and some selected exophytic T4 lesions of the suprahyoid epiglottis received irradiation for their laryngeal lesion. A satisfactory control of the laryngeal disease has been obtained with preservation of a normal voice ranging from 88.5 percent for T1 lesions to 60 percent for T4 lesions.

Comparing the groups of patients who had surgery alone or postoperative irradiation an NED rate of 63 percent was found in the latter group which is clearly superior to the 37 percent found in the surgery only group. There is no difference for the five‐year NED rates, because the patients who had surgery and postoperative irradiation had more advanced neck disease which is a cause for distant metastases. The incidence of recurrences above the clavicles is clearly less in the patients having had surgery and postoperative irradiation than in those who had surgery alone. Correlating in the two groups, surgery only and surgery followed by planned irradiation, the surgical staging of the neck metastases with recurrences above the clavicles within 24 months after treatment, it was found that the planned combined treatment has reduced the recurrence rate from 45 percent to 15 percent in the N2 and N3 patients.

Postoperative irradiation should be given routinely after resection for all T4 lesions and for any T3 lesion which extends to the pharyngeal wall(s), vallecula, base of tongue, and pyriform sinus. Postoperative irradiation should also be given for any patient whose nodal classification is greater than N1. Irradiation should be given within six weeks (preferably three to four weeks) after the surgical procedure. To achieve this goal, the operation need only remove grossly detectable disease.
The safety of intubation in croup and epiglottitis: An eight‐year follow‐up.
Authors: Schuller David E. , Birck Herbert G.
Published: October 2006

A series of 815 infectious croup (i.e., laryngotracheobronchitis) cases and 55 epiglottitis cases, encompassing an eight‐year interval, is reviewed to determine the incidence of adverse effects of nasotracheal intubation used to manage upper airway obstruction. The racial, sex, and age distributions, in addition to modalities of treatment, are presented. The intubated cases (86 patients), representing 6.5 percent of all croup cases and 60 percent of all epiglottitis cases, are described in more detail with respect to presenting symptoms and physical findings. The average duration of intubation is 55 hours for epiglottitis and 88 hours for croup. The incidence of immediate, reversible complications for the entire intubated series is 7 percent. The incidence of delayed, irreversible complications, as determined by: 1. noting any persistent post‐extubation symptoms; 2. measuring peak expiratory flow rates; and 3. laryngeal polytomography, is 1.6 percent. The mortality secondary to intubation is 0 percent. The complication rate (1.6 percent) in this series of nasotracheal intubations is lower than the mortality (3.6 percent) in a large collective series of pediatric tracheotomies performed for airway obstruction in croup or epiglottitis. Other advantages of intubation vs. tracheotomy are described (i.e., shorter hospital stay, dilatatory effect of endotracheal tube). The authors conclude that nasotracheal intubation is safer than pediatric tracheotomy and should be considered the procedure of choice in the management of upper airway obstruction secondary to croup or epiglottitis.
The use of spectrograms in the evaluation of vocal cord injection.
Authors: Rontal Eugene , Rontal Michael , Rolnick Michael I.
Published: October 2006

The utilization of voice spectrography can be an important adjunct to the assessment of vocal cord function by both laryngologists and speech pathologists. It is especially useful in determining the effectiveness of vocal cord Teflon paste injection procedures. Dysphonic characteristics are made visible, and their improvement can be monitored. As such, spectrographic analysis should be considered as a useful tool for the laryngologist.
Frontal sinus disease: III. Experimental and clinical factors in failure of the frontal osteoplastic operation.
Authors: Schenck Nicholas L.
Published: October 2006

The surgical approach to frontal sinus disease has been subject to much variation. Experimental evidence for new treatment modalities is quite limited. Frontal osteoplasty, while probably the best procedure to date, has up to a 25 percent failure rate. Possible complications include recurrent disease, incomplete bony obliteration (Macbeth technique), infection of the adipose implant, frontal bossing or depression, and laceration of the dura.

Four experimental groups were designed using the canine frontal sinus model. Results indicated that stripping the mucosa in a normal sinus with intact periosteum and a patent nasofrontal duct will not consistently lead to normal mucosal regeneration. Second, the additional factor of removing the periosteum (as in osteoplasty by osteoneogenesis), leads to partial fibrous obliteration complicated by mucocele formation. Third, sinus obliteration by osteoneogenesis was much more consistent with concurrent closure of the nasofrontal duct. Fourth, intentionally leaving a strip of mucosa leads to failure of obliteration by osteoneogenesis 100 percent of the time. Finally, bony‐fibrous obliteration increases with time but is still incomplete after one year.

In light of these results, fat obliteration with closure of the nasofrontal duct is probably more reliable than obliteration by osteoneogenesis.
Mucosal melanomas of the head and neck.
Authors: Barton Richard Thomas
Published: October 2006

Malignant melanomas arising from the mucosal areas of the head and neck are rare. When such neoplasms are encountered, the problem of their management is often poorly resolved. Cases of primary malignant melanoma of the maxillary sinus, the nasopharynx, oral cavity and laryngo‐pharynx are presented and the results of treatment analyzed.

Much of the difficulty in therapy is due to an incomplete understanding of the mechanisms which determine survival. A brief discussion of melanoma immunology is presented. Surgery (including cryosurgery) remains the primary therapy when possible. The role of chemotherapy, immunotherapy and radiation therapy in such lesions cannot be clearly delineated at this time.
Certain effects of adenoidectomy on eustachian tube ventilatory function.
Authors: Bluestone Charles D. , Cantekin Erdem I. , Beery Quinter C.
Published: October 2006

In an effort to develop a simple and accurate method to identify children in whom adenoidectomy might prevent otitis media, the ventilatory function of the Eustachian tube was assessed by a manometric technique. Nasal pressures during swallowing were also determined in some. The study group consisted of 23 children with otitis media in whom tympanostomy tubes had been inserted. All were judged clinically and roentgenographically to have prominent adenoids. Inflation‐deflation Eustachian tube ventilation studies were obtained in 36 ears that remained intubated, aerated and dry both before and eight weeks after adenoidectomy. Fifteen of the 36 (42 percent) ears had improvement in Eustachian tube ventilatory function postadenoidectomy which was attributed to relief of extrinsic mechanical obstruction of the tube. In the remaining 21 (58 percent) ears in which Eustachian tube function was not improved, mechanical obstruction was not apparent preoperatively. The effect of nasopharyngeal pressures on a pliant Eustachian tube (Toynbee phenomenon) due to obstruction of the posterior nasal choanae by the adenoid mass was suggested as a possible cause of functional Eustachian tube obstruction. In several instances in which preadenoidectomy mechanical obstruction of the Eustachian tube was not demonstrated, the tube appeared to have been made more pliant by the operation. This increase in compliance of the Eustachian tube was attributed to loss of adenoid support of the tube in the fossa of Rosenmuller.

From this study, preliminary recommendations for selection of patients for adenoidectomy are the following: 1. Eustachian tube ventilation function tests in a dry, intubated middle ear; 2. if extrinsic mechanical obstruction of the Eustachian tube is present and chronic inflammation is absent, adenoidectomy will probably improve Eustachian tube function. The surgical technique should include adequate removal of the adenoid tissue in the fossa of Rosenmuller; 3. if the Eustachian tube does not appear to be mechanically obstructed, the adenoids should not be removed unless functional obstruction is suspected due to obstruction of the posterior nasal choanae. Adenoid tissue within the fossa of Rosenmuller should not be removed when such circumstances exist; and 4. in the absence of obstructive adenoids to the nasal choanae or Eustachian tube, adenoidectomy probably will not improve Eustachian tube function and could make it worse. A more rational and effective approach to adenoidectomy for the prevention of otitis media in children may be possible through this type of preoperative evaluation.
Surgery for chronic hyperplastic rhinosinusitis
Authors: Friedman William H.
Published: October 2006

Davison pointed out in 1953 that his purpose in treating sinusitis was to utilize the smallest amount of surgery that would produce permanent relief of symptoms. By 1963 he had become convinced that extensive disease required extensive surgery. Hyperplastic rhinosinusitis is treated by a variety of surgical techniques including polypectomy, turbinate cautery, submucous resection of the turbinates or nasal septum, anterior ethmoidectomy, and spheno‐ethmoidectomy.

Sixty‐eight patients are presented who have undergone bilateral spheno‐ethmoidectomy between January, 1969, and January, 1974. These patients were predominantly allergic, with a high percentage of previous polypectomies and desensitization which failed to control their recurring nasal polyps. Ten patients were lost to follow‐up. Forty‐seven of 68 patients have had no recurrence of polyps in from 12 to 60 months. All patients continued to have mucosal manifestations of allergy or infection, but the recurrence of late polyps was limited to 11 patients.

The spheno‐ethmoidectomy technique is utilized, stressing complete removal of the middle turbinate. Kidder has shown an improved rate of polyp control in patients following ethmoidectomy with middle turbinate removal rather than with partial or total preservation of the middle turbinate. Complete resection of the middle turbinate with opening of the sphenoid air sinus permits a thorough exenteration of the ethmoid labyrinth and better control of chronic disease. A complication rate of 5.9 percent is presented and is deemed acceptable, since there were no disabling complications or complications related to poor visualization.
Silent otitis media
Authors: Paparella Michael M. , Shea Don , Meyerhoff William L. , Goycoolea Marcos V.
Published: October 2006

There is a traditional view that chronic otitis media and chronic mastoiditis must exist in the presence of a tympanic membrane perforation. Based on a human histopathological study of 123 temporal bones with chronic otitis media out of 333 temporal bones with all forms of otitis media pathology, only 24 patients (36 ears) had symptoms of otological disease recorded on their charts and only 19.5% of these had an associated tympanic membrane perforation. Unsuspected findings of chronic otitis media (active or inactive) are occasionally confirmed at exploratory tympanotomy. Such quiet chronic pathological findings in the middle ear have occurred in association with endolymphatic hydrops and cochlear end organ lesions suggesting the possibility that silent chronic otitis media may help explain sensorineural hearing loss, vertigo, and tinnitus for certain patients.

We put forth the hypothesis that clinically undetectable silent otitis media in neonates and infants might help explain why certain children are otitis media prone. Our otopathology laboratory includes 111 ears harvested from neonates and infants (average age 8 months). Histological analysis revealed normal findings in some, whereas significant numbers of others show all forms of otitis media, including purulent otitis media, chronic otitis media, serous otitis media, and mucoid otitis media, with occasional overlap of types.

Clinical implications will be discussed wth emphasis on silent otitis media and its relationship to the pathogenesis of otitis media and silent chronic otitis media and its possible role in causing insidious labyrinthine changes.

A significant outcome of this study was the marked degree of unresolved mesenchyme in the clinically manifest otitis media group or silent otitis media group as compared to a control group. This association and role of mesenchyme is discussed relative to the pathogenesis of infantile otitis media.
Surgical correction of goldenhar's syndrome
Authors: Mathog Robert H. , Leonard Myer S.
Published: October 2006

Goldenhar's syndrome is a variant of hemifacial microsomia — one of the more common congenital syndromes of the first and second arch. The Goldenhar's type is characterized by varying degrees of underdevelopment of craniofacial structures. The major deformities involve the mandible and the ear; but they also include the orbit and vertebral column, specific defects pathognomonic of this condition. Medical management requires reconstructive surgery of which treatment must take into consideration the timing of surgery and the effects of surgery upon the growth and development of the poorly formed structures.

This paper presents a discussion of the pathogenesis and the favorable and unfavorable factors affecting the selection and timing of surgery. The literature is reviewed and two additional cases are added with an evaluation of the effects of early reconstruction. A single‐stage procedure, utilizing rib autograft, is described for correction of the defective hemimandible, glenoid fossa, and zygoma. The results are evaluated by means of photographs and radiographs with a follow‐up period of at least one and one‐half years. The data suggest a remodeling of the grafts to resemble normal structures, and a downward growth of the maxilla to fill a space created by the reconstruction of the mandible and expansion of the lower portion of the face. Mupltiple stages of surgery as well as unnecessary delays in performing surgical procedures are challenged by the report.
Mass management of otitis media in Zaire
Authors: Mahoney Jack L.
Published: October 2006

In 1976, 4, 281 cases of otitis media with otorrhea were treated in the otorhinolaryngology department at Mama Yemo hospital, the 2,000‐bed major medical center in Kinshasa, Zaire. Topical aluminum acetate (Burow's solution) on ear wicks of cotton was placed against the ear drum into the ear canal and changed daily as an effective method of mass control of this disease without antibiotics. The results were comparable to those from 0.3% topical gentamycin ophthalmic solution (Garamycin®), but were obtained with considerably less expense in an area where economic considerations are essential.
Granulomatous laryngitis of unknown etiology
Authors: Haar Jean G. , Chaudhry Anand P. , Kaplan Howard M. , Milley Paul S.
Published: October 2006

A 21‐year‐old man was admitted for odynophagia and hoarseness of four months duration. He smoked one and a half packs of cigarettes a day and occasionally inhaled marijuana. Indirect laryngoscopy revealed a massive swelling of the entire epiglottis, aryepiglottic folds, and arytenoids. The histopathologic diagnosis of chronic but active nonspecific inflammation was made. Combined antibiotics and steroid therapy gave temporary relief. He was readmitted several months later with progressive shortness of breath, dysphagia, and hoarseness. Biopsy of the epiglottic tissues showed multiple noncaseating epithelioid granulomatous lesions consistent with sarcoidosis. All pertinent laboratory tests failed to establish a definitive diagnosis. The patient eventually underwent supraglottic laryngectomy. He has been symptom‐free for 20 months following surgery.
Pathology of vascular sensorineural hearing impairment
Authors: Belal A.
Published: October 2006

Circulatory disorders, which are well documented in most parts of the human body, are not well documented in the inner ear, although they are expected to occur. It has been previously shown that experimental occlusion of the labyrinthine artery in animals results in severe degenerative changes, fibrosis, and new bone formation in the cochlea. Accordingly, this paper presents presumptive evidence that depriving the human cochlea of its blood supply after surgical removal of an acoustic tumor results in severe degenerative changes that progress to total ossification of the cochlear spaces. This paper also discusses similar changes seen in temporal bones of two patients with sudden sensorineural hearing impairment.

Based on these observations, the author concludes that occlusive arterial disease, whether thrombotic, embolic, or spastic, plays a role in some sudden sensorineural hearing losses. Cochlea ossification, detected by polytomography, suggests a vascular etiology of the hearing impairment.

Treatment with vasodilator drugs and anticoagulants is justified in these cases until a better diagnostic protocol is developed to eliminate other causes.
Size of the mastoid air cell system in children with middle ear effusion
Authors: Lindeman Pontus , Shea John J.
Published: October 2006

The mastoid air cell system probably functions as an air reservoir. Among adults with chronic otitis media a small mastoid air cell system is prevalent In cases of chronic non‐purulent middle ear effusion among children, the reports have been contradictory concerning the size of the mastoid air cell system. In the present investigation, white children with long‐standing problems of middle ear effusion have been examined by means of X‐rays of the mastoid process in the lateral projection and the size of the air cell system measured by planimetry. The size of the air cell system was found to be significantly smaller in comparison with normal white children.
Etiology of otitis media with effusion: Antihistamines—decongestsnts
Authors: Peerless Sidney A. , Noiman Allen H.
Published: October 2006

In an attempt to find a causative factor for the increased incidence of otitis media with effusion, a detailed study of 50 cases was conducted. This study included 50 cases of non‐purulent otitis media with effusion requiring ventilating tubes without tonsilloadenoid pathology. A study of these cases revealed an interesting pattern which suggests that antihistamines and decongestants may be causative or precipitating factors in the etiology of otitis media with effusion. A pilot study on the effects of these drugs on mucociliary activity was conducted and revealed further evidence that antihistamines and decongestants interfere with normal mucociliary activity which probably is a factor in abnormal Eustachian tube physiology.
Bone destruction due to the rupture of a cholesteatoma sac: A pathogenesis of bone destruction in aural cholesteatoma
Authors: Kaneko Yutaka , Yuasa Ryo , Ise Ikuo , Iino Yukiko , Shinkawa Hidbichi , Rokugo Masaaki , Tomioka Sachiko , Shibahara Yoshihiro
Published: October 2006

Severe bone destruction in a cholesteatoma is one of the characteristic clinical features. To clarify the mechanism of bone destruction in cholesteatoma, the matrix of cholesteatoma and the attached bone, obtained during middle ear surgery, was observed by light microscope. Rupture of the epithelial lining in a cholesteatoma and the escaping contents (keratin), which gave rise to intense characteristic granulations in subepithelial tissue, were found. Furthermore bone destruction was always found at the site of subepithelial tissue of cholesteatoma. From these facts, the escape of contents from the sac of cholesteatoma into the subepithelial layer is considered to be an important factor in the mechanism of bone destruction.
Separation of the larynx and trachea for intractable aspiration
Authors: Baron Barry C. , Dedo Herbert H.
Published: October 2006

Aspiration becomes an intractable problem for some patients who have lost normal neurological function of the glottis. Over the long term, a cuffed tracheotomy tube is inadequate. Several methods have been developed to relieve this problem surgically. These include the use of muscle flaps, tracheoesophageal anastomosis, and use of an epiglottic flap. In this paper, we discuss these previous surgical attempts to alleviate aspiration and present our own technique, which involves creation of a tracheostome and closure of the larynx at the level of the first tracheal ring. This has been used with success in three patients. We feel this technique is less complex and results in less surgical trauma to the larynx, important factors when dealing with critically ill patients. This_ technique is theoretically reversible by re‐anastomosing the trachea to the cricoid cartilage after excising the first tracheal ring.
Antral‐ethmoidal decompression of the orbit in graves' disease: Ten‐year experience
Authors: Calcaterra Thomas C. , Thompson Jerome W.
Published: October 2006

The orbital manifestations of Graves' disease usually comprise the most distressing component of this inadequately understood disease entity. Patients with optic neuropathy, exposure keratopathy, or disfiguring proptosis can be helped considerably by decompression of the swollen orbital tissues into the maxillary and sinus cavities. Experience with 104 patients personally operated by the senior author and analyzed by chart review and patient questionnaire indicates that antral‐ethmoidal decompression is a successful form of therapy, generally free of serious complications. It is now employed earlier in the course of Graves' ophtholmopathy than in the past.