bluuebunny/crossref_metadata_2025 huggingface dataset:
Intact acoustic reflexes in the presence of ossicular disruption
Authors: Jenkins Herman A. , Morgan Donald E. , Miller Robert H.
Published: October 2006

The potential usefulness of impedance studies is reviewed and a case of osteogenesis imperfecta, having bilateral ossicular discontinuity and intact acoustic reflexes, is presented. This seeming paradox was explainable on the basis of surgically confirmed, bilateral disruption of the stapes crura, central to the stapedial tendon insertion.
Local IgA‐Class antibodies against respiratory viruses in middle ear and nasopharyngeal secretions of children with secretory otitis media
Authors: Meurman Olli Henrik , Sarkkinen Hannu Kalevi , Puhakka Heikki Juhani , Virolainen Erkki Simo , Meurman Otto Henrik
Published: October 2006

The presence of antibodies against some important respiratory viruses in the middle ear and nasopharyngeal secretions of 52 children with secretory otitis media (SOM) was investigated in order to find out about the role of these viruses in the development of SOM.The method employed was a sensitive radioimmunoassay test.

Antibodies to adeno, respiratory syncytial, and parainfluenza 3 viruses were detected in about 50%, 50% and 20% of the patients, respectively. In eight patients the middle ear secretion/nasopharyngeal secretion titer ratio of antibodies to one virus was selectively increased in comparison with the other viruses tested, indicating an active local production of specific antibodies in the middle ear.

Further studies are required to determine the cause of such an active antibody synthesis and its possible role in the etiopathogenesis of SOM.
Tinnitus: Development of a neurophysiologic correlate
Authors: Sasaki Clarence T. , Babitz Lisa , Kauer John S.
Published: October 2006

Although tinnitus severely afflicts 7.2 million Americans, the pathophysiology of this problem remains obscure because there presently exists no good animal model in which to study the phenomenon. We have examined changes in activity in the guinea pig auditory pathway using an autoradiographic method of functional brain mapping after short‐term and long‐term cochlear ablations which can, in humans, initiate the occurrence of tinnitus. With this method we have observed a reduction in activity in various nuclei in the auditory pathway between 4 hrs and 10 days after unilateral cochlear ablation. In contrast to these findings we have found a return of activity in these same nuclei if they are observed from 12 to 48 days following the lesion. These preliminary data suggest that this return of activity in the absence of sensory input may be a valid experimental analogue for tinnitus in humans. Such evidence for auditory plasticity may represent a significant first step toward understanding this common and profound otologic symptom.
Viability of skin flaps subjected to simultaneous chemical peel with occlusive taping
Authors: Hayes David K. , Stambaugh Kweon I.
Published: October 2006

This study was undertaken to determine whether the application of a standardized chemical peel with an occlusive tape dressing to an acutely raised skin flap (as in combining rhytidectomy with chemical peel) affects skin flap viability. Thirty‐six 4‐cm x 4.cm dorsal skin flaps were raised on guinea pigs and sutured back into place. Eighteen of these flaps were simultaneously treated with a single application of Baker's solution and a 24‐hour occlusive tape dressing. A mean of 3.1 cm2 of the non‐peeled flaps necrosed, compared with 6.3 cm2 of the peeled flaps, a statistically significant increase in tissue loss in flaps that were simultaneously chemically peeled. We conclude that application of Baker's solution with an occlusive tape dressing to an acutely raised skin flap impairs skin flap viability and may result in skin flap necrosis.
Jugular foramen peripheral nerve sheath tumors
Authors: Franklin Daniel J. , Moore Gary F. , Fisch Ugo
Published: October 2006

Though jugular foramen nerve sheath tumors are uncommon, they involve a critical area of the skull base. Therefore, a precise classification system is needed to accurately define the extent of these tumors and reflect their surgical management. A series of seven cases is reviewed incorporating such a classification system to illustrate the management of these lesions using the in‐fratemporal fossa type A approach.
Role of air contrast computed tomography in diagnosis of small acoustic neuromas
Authors: Lipkin Alan F. , Jenkins Herman A.
Published: October 2006

Small acoustic tumors occasionally cannot be diagnosed on standard radiologic studies. Over a 2‐year period, air contrast computed tomography (CT) has been used to study 22 patients in whom audiologic and vestibular tests suggested a tumor but no radiologic abnormality could be demonstrated; 8 air contrast scans were positive and subsequent exploration revealed tumors in 7 of these patients. In one patient an aneurysmally dilated anterior inferior cerebellar artery was found on exploration. Thirteen scans showed air filling the internal auditory canal with no evidence of tumor. One scan was nondiagnostic and upon exploration, a vascular loop in the internal auditory canal was found.

Air contrast high resolution CT is the most accurate method available for detecting small acoustic neuromas. Indications for this technique are discussed along with general approaches to these patients.
Pseudomonas aeruginosa in chronic maxillary sinusitis
Authors: Maisel Barry O. , Koltai Peter J. , Goldstein Jerome C.
Published: October 2006

Psendomonas aeruginosa (Ps. Au.) infection of the maxillary sinus has been reported as an incidental finding on routine antrostomy; however, it has also been noted in several studies as the significant organism in the etiology of chronic sinusitis. Four case reports of culture verified Ps. Au. maxillary sinusitis are presented. The therapeutic modality used in two of the cases was a Caldwell‐Luc operation and in two, an intranasal antrostomy. In all cases, multiple irrigations through the surgically created nasoantral windows were done postoperatively, as was the instillation of gentamicin ophthalmic drops intranasally. In all four cases the infection cleared with this combined surgical and medical therapy.
Heat myringotomy
Authors: Shelton Clough , Lau Pauline , Goode Richard L.
Published: October 2006

Heat myringotomy using a commercially available, battery powered device produced an opening in the tympanic membrane that persisted 1 to 3 weeks. The procedure was performed to treat chronic otitis media with effusion (COME) in lieu of ventilation tubes in 10 pediatric and 15 adult ears under office iontophoretic anesthesia. These patients were followed for a minimum of 3 months to assess efficacy. Fifty percent of pediatric ears were controlled, eliminating the need for general anesthesia and tube insertion. Forty percent of adult ears were controlled with heat myringotomy. A description of the procedure, discussion of possible reasons for failure, and analysis of potential cost savings are included.
Basic metabolic rate in emotional stress: Its potential influence on cochlear function
Authors: Muchnik C. , Hlldesheimer M. , Rubinstein M. , Molho M.
Published: October 2006

Using a model previously described, prolonged emotional stress was induced in guinea pigs. Under this condition, arterial blood gases, blood glucose level, PO2 and PCO2 in the expired air, and the heat irradiated by the animals were measured and compared to those of the anesthetized guinea pigs. From the present study, two important findings should be mentioned. First, the metabolic rate of the animals under stress was 30% higher than in the anesthetized group. Second, the arterial PO2 level of the animals under stress was significantly lower than that in the anesthetized ones. Evaluating the noxious effect of severe and/or prolonged emotional stress, one should not neglect the increased oxygen demand resulting from the high metabolic rate of the subject. This factor, together with the decreased arterial blood PO2 level, reinforce the hypoxic effects on the cochlear function, caused by the vasoconstriction of the labyrinthine vessels.
Diagnostic potential of CT in neurotological disorders
Authors: Mafee Mahmood F. , Kumar Arvind , Valvassori Galdino E. , Dobben Glen D. , Meyer Dianne
Published: October 2006

The reliability of a neurotological evaluation in differentiating labyrinthine (end organ) lesions from retrolabyrinthine lesions has been well established. The purpose of this communication is to determine the diagnostic potential of computed tomography (CT) in patients suspected of having retrolabyrinthine lesions on the basis of their neurotological evaluations. Our study indicates that the validity of central vestibular and audiometric signs can be best substantiated with CT. The anatomy of neurovascular bundles within the internal auditory canal and cerebellopontine cistern can be readily visualized and identified by CT pneumocisternomeatography. By obtaining appropriate thin CT sections not only can very small lesions be identified but their anatomic locations can also be accurately established. CT pneumocisternomeatography is the method of choice to diagnose an intracnnalicular acoustic neuroma. An unusually large vascular loop of the internal auditory canal may be responsible for sensorineural hearing loss and tinnitus in some patients.
Fixation of laryngeal stents
Authors: Mouney Daniel F. , Lyons George D.
Published: October 2006

With the advent of the CO2 laser, the transendoscopic placement of stents and keels has become an important adjunct in the surgical treatment of laryngeal webs and stenosis. Fixation of stents, however, is often difficult and cumbersome. Here, we describe two relatively simple techniques of laryngeal stent construction, placement, and fixation.
Tinnitus and/or hearing loss elicited by facial mimetic movement
Authors: Yamamoto Etuso , Nishimura Hiroko , Iwanaga Michitaka
Published: October 2006

Temporary tinnitus and/or hearing loss elicited by contraction of facial mimetic muscles are often observed on the affected side in patients recovering from facial nerve paralysis and in those with facial spasm. In order to clarify the mechanism of this phenomenon, changes in auditory threshold and middle ear compliance during voluntary contraction of mimetic muscles were investigated. The results suggest that this type of tinnitus and/or hearing loss is due to nonacoustic contraction of the stapedial muscle synchronous with contraction of mimetic muscles.
Brush cytology for the early detection of esophageal carcinoma among patients with upper aerodigestive malignancies
Authors: Dowlatshahi Kambiz , Lester Eric , Bibbo Marluce , Johnson Charles
Published: October 2006

The incidence of associated esophageal carcinoma (EC) among patients with upper aerodigestive tract malignancies is high. Esophageal brush cytology, as developed and evaluated as a screening device for early detection of EC among villagers of northeastern Iran,1 was employed to examine 56 clinic patients with known tumors of the upper aerodigestive tract on 106 occasions. Two asymptomatic EC were detected and are presented. The procedure was also used as an adjunct to endoscopy in order to monitor the response of tumors under treatment. Sensitivity of 40% and specificity of 90% were found and could be improved with more judicious application of the procedure. The use of this simple test for early detection of EC among this high risk subset of clinic patients is recommended.
Open mastoid procedures: Contemporary indications and surgical technique
Authors: Jackson C. Gary , Glasscock Michael E. , Nissen Alan J. , Bojrab Dennis I. , Schwaber Mitchell K.
Published: October 2006

The history of the management of chronic ear disease with and without cholesteutoma is dominated by a canal wall down philosophy. The implication is that such an open procedure insures disease control and an uncomplicated future.

In point of fact, problem canal wall down procedures can be fraught with as many seríous complications as their more controversial canal wall up counterpart is alleged to propagute. Such problem cavities most commonly result from poor execution of basic technique.

The objective of this paper is to identify what constitutes a problem cavity and to describe the authors' techniques to avoid such difficulties. A technique has evolved which not only eradicates disease, but which is self‐cleansing and of minimal impact on the patient's lifestyle. The authors' experience with canal wall down procedures is reviewed.
The effects of anesthesia on middle‐eae effusions
Authors: Fried Marvin P. , Vernick David M. , Kelly James H. , Silberstein Victoria , Strome Marshall
Published: October 2006

Surgeons occasionally note a discrepancy between preoperative assessment of middle‐ear effusion and operative observation during the placement of ventilating tubes in children's ears. This study was designed to determine whether this variance is secondary to the effects of inhalation anesthesia or misinterpretation of the preoperative exam. Observations were recorded by three distinctly different methods of measurement: the surgeon, the MD‐2 Impedance Analyzer, and the Acoustic Otoscope® immediately before and after induction of anesthesia. These results were then analyzed and compared with the operative findings. Anesthetic induction was shown to cause alteration in the presence of middle‐ear fluid in less than 10% of cases.
SCC‐RIA in the diagnosis of squamous cell carcinoma of the head and neck
Authors: Eibling Col David E. , Johnson Jonas T. , Wagner Robin L. , Su Sean
Published: October 2006

A reliable circulating tumor marker, appropriate for head and neck malignancy, is not yet available. This manuscript reports the efficacy of using circulating squamous cell carcinoma antigen in evaluating patients with squamous cell carcinoma of the head and neck.

Serum samples from 89 patients with squamous cell carcinoma of the head and neck were obtained before treatment and at intervals following treatment. Squamous cell carcinoma antigen levels were determined by radioimmunoassay.

Elevated pretreatment serum levels of squamous cell carcinoma antigen were identified in 39 of 89 patients (44%) who had head and neck squamous cell carcinoma. Of the 16 patients evaluated from this group with recurrent or persistent disease, 15 (93.5%) demonstrated elevated levels of squamous cell carcinoma antigen. However, of the 21 evaluable patients who remained disease free, only 10 (48%) had post‐therapy levels within the normal range. The possible use of this marker in aiding the clinical follow‐up of head and neck cancer patients is discussed.
Acoustic neuroma—the patient's perspective: Subjective assessment of symptoms, diagnosis, therapy, and outcome in 541 patients
Authors: Wiegand David A. , Fickel Virginia
Published: October 2006

Surgical treatment of acoustic neuroma has been reviewed in the medical literature, but assessment of outcome from the patient's perspective has received little attention. The Acoustic Neuroma Association (A.N.A.) is a large organization of acoustic neuroma patients which provides information and support services. This article reports the subjective assessment of symptoms, diagnosis, treatment, and outcome as evaluated by 541 A.N.A. members. This retrospective study presents an extensive overview of the experience of acoustic neuroma patients treated at a variety of institutions, and provides a unique perspective not previously represented in the medical literature.
Brainstem auditory evoked potentials with increased stimulus rate in patients suffering from systemic lupus erythematosus
Authors: Fradis Milo , Podoshin Ludwig , Ben‐David Jacob , Statter Pioter , Pratt Hillel , Nahir Menahem
Published: October 2006

Central nervous system involvement in systemic lupus erythematosus is frequently occult, may be the presenting sign, and is a bad prognostic indicator. At present, there is no reliable, sensitive laboratory test for the evaluation and diagnosis of subclinical central nervous system involvement of the disease. Brainstem auditory evoked potentials with and without increased stimulus rate have been used to diagnose ischemic lesions in the central nervous system.

Brainstem auditory evoked potentials, with and without increased stimulus rate, was used to investigate 15 systemic lupus erythematosus patients, 20 normal participants, and 5 patients receiving corticosteroids for bronchial asthma. A significant statistical difference was found in the net effect of increased stimulus rate in comparisons of the systemic lupus erythematosus patients with the normal group. Brainstem auditory evoked potentials, with increased stimulus rate, demonstrated subclinical involvement of the central nervous system in systemic lupus erythematosus, reinforcing the notion that increased stimulus rate measures are sensitive to ischemic changes, in this case, even in neurologically asymptomatic patients.
The role of fenestrated vessels for the secretory process in the nasal mucosa: A histological and transmission electron microscopic study in the rabbit
Authors: Grevers G.
Published: October 2006

Both nasal glands and nasal vessels are supposed to be responsible for the humidification of inhaled air. After previous studies on the vasculature of the nasal septal mucosa in the rabbit, we examined vessels of the anterior concha in order to find a morphological equivalent to explain the role of endonasal vasculature in the secretory process of this tissue. The main findings of our study include the detection of fenestrated endothelial walls of both capillaries and venous sinuses located underneath and directly adjacent to the basal cell layers of the epithelium. The same phenomenon fenestrated vessels underneath the epithelium with the fenestrated parts facing the epithelial cells has been described in other parts of the body and has been called “polar differentiation.” In accordance with the interpretations of other authors, we conclude that these features are responsible for the regulation of endonasal fluid exchange.
The effect of intracranial surgical trauma on gadolinium‐enhanced magnetic resonance imaging
Authors: Millen Steven J. , Daniels David L.
Published: October 2006

Gadolinium‐enhanced magnetic resonance imaging (MRI) is currently the gold standard for diagnosis of an acoustic neuroma. Its status in diagnosis of a recurrent or residual neuroma is not nearly as clear. A pilot study of 36 postoperative cases showed enhancement in 100% of the patients at the operative site. To examine the role of surgical trauma and biodegradable packing on enhanced MRI, an animal study was designed. Cats and monkeys that underwent posterior fossa surgical procedures had preoperative and postoperative MRI and histologic correlation of any enhanced area. Areas of postoperative enhancement should not be considered as diagnostic of tumor. Further studies are necessary to develop a criteria for recurrent tumor diagnosis with enhanced MRI.
Sleep and posture
Authors: Tvinnereim Magne , Cole Philip , Haight James S. J. , Mateika Susan , Hoffstein Victor
Published: October 2006

Computer‐assisted open catheter studies of 10 healthy, nose‐breathing men in dorsal and in lateral recumbent sleep demonstrated stable intrasubject transpharyngeal differential pressures and airflow resistances. They averaged 19.6 Pa (± standard deviation [SD] 11.9) and 0.103 Pa/cm3 per second (± SD 0.065) in the dorsal posture and stage II sleep during quiet breathing and were not significantly different in the lateral posture or in stage I sleep. Five subjects were snorers, and their pharyngeal airflow pressures and resistances increased substantially during quiet breathing on assumption of recumbency and much more in sleep. In the 5 subjects who were nonsnorers, postural changes were not significant and sleep increases were moderate. During snoring, transpharyngeal pressures and resistances increased even further, averaging 188 Pa and 1.02 Pa/cm3 per second for the whole group. Transpharyngeal differential pressures and hypopharyngeal transmural pressures frequently exceeded 300 Pa in inspiration and in expiration during periods of snoring. Yet, transpharyngeal differential pressures and resistances did not reveal appreciable differences between phases that would indicate compliant change of pharyngeal cross section. Breathing frequency was unchanged, but ventilation was significantly diminished at elevated upper airway resistances (P<.01). Transpharyngeal resistances and differential pressures varied independently from widely differing nasal resistances. As with our earlier studies, pressure measurements alone clearly demonstrated breathing patterns and events.
Intraepithelial lymphocyte subpopulations and dendritic accessory cells in normal and hypertrophic adenoids
Authors: Bani Daniele , Gallo Oreste , Fini‐Storchi Omero
Published: October 2006

The adenoids have been studied by immunocytochemistry and electron microscopy in children with and without adenoidal enlargement. Compared with normal adenoids, the enlarged ones showed a marked increase in the number of intraepithelial gamma‐delta TCR+ lymphocytes and a slight increase in the number of intraepithelial CD8+ lymphocytes. This was accompanied by large amounts of dendritic human lymphocyte antigen (D related) (HLA‐DR+) S‐100+ accessory cells in the lymphoid tissue underlying the epithelium. By electron microscopy, dead epithelial cells apposed to intraepithelial lymphocytes, and clefts of the epithelial lamina, could be seen frequently in the enlarged adenoids, whereas, in the normal ones, they could not. Based on these findings, the hypothesis is drawn that imbalance of the system of the intraepithelial cytotoxic lymphocytes may lead to increased killing of epithelial cells and uncontrolled penetration of exogenous agents, and hence be involved in the pathogenesis of adenoidal hypertrophy.
Methotrexate therapy for autoimmune hearing loss: A preliminary report
Authors: Sismanis Aristides , Thompson Tab , Willis Hayes E.
Published: October 2006

The management of autoimmune sensorineural hearing loss (SNHL) continues to challenge the otologist. Steroids and cyclophosphamide, the two traditional medications for this malady, are often associated with serious adverse reactions. In an effort to use a less toxic medication, the authors treated five autoimmune SNHL patients with low‐dose oral methotrexate. Methotrexate has been found to be very effective in rheumatoid arthritis patients with acceptable adverse reactions. Preliminary results from this study indicate that methotrexate has the potential of being effective for autoimmune SNHL and associated otologic symptoms. Tolerance has been very good and side effects have been minimal.
Glottic configuration after arytenoid adduction
Authors: Woodson Gayle E. , Murry Thomas
Published: October 2006

It has been recently noted that laryngeal paralysis results in a complex alteration of the glottis. The membranous segment of the paralyzed vocal fold is shortened, and, during phonation, patients use hyperfunction to shorten the normal vocal fold to about the same length. Additionally, if the paralyzed vocal fold is not near the midline, the angle between the membranous and cartilaginous segments of the vocal fold is decreased, resulting in a “posterior” gap which cannot be closed by hyperadduction of the normal side. To determine whether arytenoid adduction addresses these problems, videolaryngoscopy was analyzed in 11 patients before and after surgery, and results were compared to patient satisfaction and acoustic and aerodynamic assessment. The posterior gap and glottic competence were improved in all patients, but only 6 had improvement in symptoms. Two had persistent vocal fold bowing but achieved good function after Teflon® injection. Three patients, all with paralysis for more than 20 years, had no increase in vocal fold length and very little subjective vocal improvement. Arytenoid adduction is most effective in acute cases. Poor functional results in chronic paralysis are related to failure to achieve vocal fold lengthening, presumably due to soft‐tissue contracture.
Magnetic resonance imaging of intratemporal facial nerve lesions in the animal model
Authors: Orloff Lisa A. , Duckert Larry G.
Published: October 2006

The facial nerve is often injured in head trauma. Computed tomography (CT) is the diagnostic study most frequently used to evaluate temporal bone fractures, but it does not demonstrate all soft tissues well. Recently, magnetic resonance imaging (MRI) has been used to evaluate certain soft tissues, including cranial nerves. Experience with MRI evaluation of temporal bone trauma is limited and consists primarily of anecdotal reports. This study assesses the accuracy of MRI in evaluating experimentally induced acute intratemporal facial nerve lesions. The tympanic segments of the right facial nerve in nine rabbits were contused, and MRI scans were performed without and with gadolinium‐diethyl‐triamine‐pentaacetic acid (Gd‐DTPA) at varying intervals after surgery. MRI with Gd‐DTPA accurately identified the lesion site in eight of nine subjects. Gd‐DTPA‐enhanced MRI appears to be useful in the evaluation of traumatic facial nerve injuries.
Relationship between the gas composition of the middle ear and the venous blood at steady state
Authors: Luntz M. , Levi D. , Sadé J. , Herman M.
Published: October 2006

Concomitant continuous measurements of the steady‐state gas composition of the middle ear and of the venous blood were recorded by mass spectrometry in four guinea pigs. The following mean values were obtained for the partial pressures of middle ear gases; nitrogen + argon, 606.4 mm Hg; oxygen, 46.2 mm Hg; and carbon dioxide, 60.2 mm Hg. The corresponding values for the venous blood were as follows: Nitrogen + argon, 563.4 mm Hg; oxygen, 38.0 mm Hg; and carbon dioxide, 61.4 mm Hg. The similarity of the steady‐state gas composition of the middle ear to that of the venous blood suggests that the partial pressures of the gases in the middle ear are controlled by interchange with gases present in the blood.
The role of magnetic resonance angiography in head and neck surgery
Authors: Endres Donald , Manaligod Jose , Simonson Tereasa , Funk Gerry , Mcculloch Timothy , Hoffman Henry
Published: October 2006

Magnetic resonance angiography (MRA) is a recently developed, noninvasive vascular imaging technique. The authors of this investigation assessed the diagnostic value of MRA, along with its influence on therapeutic decisions, in 11 patients with a variety of head and neck disorders. In 5 patients, MRA diagnosed or ruled out an intrinsic vascular lesion. MRA was used to evaluate 5 of 8 patients with cancer for evidence of direct tumor involvement of vascular structures. Other uses of MRA included preoperative determination of tumor vascularity and delineation of anatomic relationships between normal vessels and head and neck pathology. Overall, MRA results guided management in 10 patients, and in some cases it determined the extent of surgical intervention. Because MRA is safer and more practical than traditional angiography, the authors recommend more frequent use of this imaging technique in the practice of head and neck surgery.
Statistical Epistasis Is a Generic Feature of Gene Regulatory Networks
Authors: Gjuvsland Arne B , Hayes Ben J , Omholt Stig W , Carlborg Örjan
Published: October 2006

Functional dependencies between genes are a defining characteristic of gene networks underlying quantitative traits. However, recent studies show that the proportion of the genetic variation that can be attributed to statistical epistasis varies from almost zero to very high. It is thus of fundamental as well as instrumental importance to better understand whether different functional dependency patterns among polymorphic genes give rise to distinct statistical interaction patterns or not. Here we address this issue by combining a quantitative genetic model approach with genotype–phenotype models capable of translating allelic variation and regulatory principles into phenotypic variation at the level of gene expression. We show that gene regulatory networks with and without feedback motifs can exhibit a wide range of possible statistical genetic architectures with regard to both type of effect explaining phenotypic variance and number of apparent loci underlying the observed phenotypic effect. Although all motifs are capable of harboring significant interactions, positive feedback gives rise to higher amounts and more types of statistical epistasis. The results also suggest that the inclusion of statistical interaction terms in genetic models will increase the chance to detect additional QTL as well as functional dependencies between genetic loci over a broad range of regulatory regimes. This article illustrates how statistical genetic methods can fruitfully be combined with nonlinear systems dynamics to elucidate biological issues beyond reach of each methodology in isolation.
The Cdc34/SCF Ubiquitination Complex Mediates Saccharomyces cerevisiae Cell Wall Integrity
Authors: Varelas Xaralabos , Stuart David , Ellison Michael J , Ptak Christopher
Published: October 2006

To identify novel functions for the Cdc34/SCF ubiquitination complex, we analyzed genomewide transcriptional profiles of cdc53-1 and cdc34-2 Saccharomyces cerevisiae mutants. This analysis revealed altered expression for several gene families, including genes involved in the regulation of cell wall organization and biosynthesis. This led us to uncover a role for the Cdc34/SCF complex in the regulation of cell wall integrity. In support of this, cdc53-1 and cdc34-2 mutants exhibit phenotypes characteristic of cell wall integrity mutants, such as SDS sensitivity and temperature-sensitive suppression by osmotic stabilizers. Examination of these mutants revealed defects in their induction of Slt2 phosphorylation, indicating defects in Pkc1-Slt2 MAPK signaling. Consistent with this, synthetic genetic interactions were observed between the genes encoding the Cdc34/SCF complex and key components of the Pck1-Slt2 MAPK pathway. Further analysis revealed that Cdc34/SCF mutants have reduced levels of active Rho1, suggesting that these defects stem from the deregulated activity of the Rho1 GTPase. Altering the activity of Rho1 via manipulation of the Rho1-GAPs LRG1 or SAC7 affected Cdc34/SCF mutant growth. Strikingly, however, deletion of LRG1 rescued the growth defects associated with Cdc34/SCF mutants, whereas deletion of SAC7 enhanced these defects. Given the differential roles that these GAPs play in the regulation of Rho1, these observations indicate the importance of coordinating Cdc34/SCF activity with specific Rho1 functions.
Contribution of Growth and Cell Cycle Checkpoints to Radiation Survival in Drosophila
Authors: Jaklevic Burnley , Uyetake Lyle , Lemstra Willy , Chang Julia , Leary William , Edwards Anthony , Vidwans Smruti , Sibon Ody , Tin Su Tin
Published: October 2006

Cell cycle checkpoints contribute to survival after exposure to ionizing radiation (IR) by arresting the cell cycle and permitting repair. As such, yeast and mammalian cells lacking checkpoints are more sensitive to killing by IR. We reported previously that Drosophila larvae mutant for grp (encoding a homolog of Chk1) survive IR as well as wild type despite being deficient in cell cycle checkpoints. This discrepancy could be due to differences either among species or between unicellular and multicellular systems. Here, we provide evidence that Grapes is needed for survival of Drosophila S2 cells after exposure to similar doses of IR, suggesting that multicellular organisms may utilize checkpoint-independent mechanisms to survive irradiation. The dispensability of checkpoints in multicellular organisms could be due to replacement of damaged cells by regeneration through increased nutritional uptake and compensatory proliferation. In support of this idea, we find that inhibition of nutritional uptake (by starvation or onset of pupariation) or inhibition of growth factor signaling and downstream targets (by mutations in cdk4, chico, or dmyc) reduced the radiation survival of larvae. Further, some of these treatments are more detrimental for grp mutants, suggesting that the need for compensatory proliferation is greater for checkpoint mutants. The difference in survival of grp and wild-type larvae allowed us to screen for small molecules that act as genotype-specific radiation sensitizers in a multicellular context. A pilot screen of a small molecule library from the National Cancer Institute yielded known and approved radio-sensitizing anticancer drugs. Since radiation is a common treatment option for human cancers, we propose that Drosophila may be used as an in vivo screening tool for genotype-specific drugs that enhance the effect of radiation therapy.
The Puente Génave-Castelo de Vide shear zone (southern Central Iberian Zone, Iberian Massif): geometry, kinematics and regional implications
Authors: Parra Luis Miguel Martín , Lodeiro Francisco González , Poyatos David Martínez , Matas Jerónimo
Published: October 2006

This paper is concerned with the existence and the salient characteristics of an extensional shear zone (the Puente Génave-Castelo de Vide shear zone) along 400 km in the southern Central Iberian Zone. This shear zone is almost parallel to the previous Variscan structures, but it is slightly cross-cut by the discontinuous late Carboniferous Alburquerque-Pedroches batholithic alignment (which has been considered by some authors to be a fundamental feature for the sub-zonation of the Iberian Massif). The shear zone dips towards the S or SW, showing a top-to-the-S sense of movement. Early ductile deformation was concentrated along a band of andalusite-rich carbonaceous shales in the shear zone, but this can also be recognized in the footwall, particularly in the eastern sector, where the southern border of the (pre- to syn-kinematic) Santa Elena stock was intensely sheared; later intrusion of dyke-swarms agrees with the extensional stress field. Finally the shear zone appears brecchiated and bounded by two brittle faults. From a regional point of view, the shear zone described separates rocks with some differences regarding their stratigraphic, igneous and structural characteristics. These differences, and their precise limits, have been the basis for numerous subdivisions of this part of the Iberian Massif during the last decades. It is our contention that if any subzonation of the southern Central Iberian Zone is to be made (namely eg : Obejo-Valsequillo Domain, Lusitan-Marianic Domain), its northern boundary should be the Puente Génave-Castelo de Vide shear zone. As for the southern boundary, it is located in the Badajoz-Córdoba suture that separates the Central Iberian Zone from the Ossa-Morena Zone.
Transformations of Carbon and Sulfur Wastewater Components Under Aerobic–Anaerobic Transient Conditions in Sewer Systems
Authors: Tanaka Naoya , Hvitved‐Jacobsen Thorkild , Horie Takashi
Published: October 2006

Wastewater quality changes in the carbon and sulfur cycles in pressure sewers and in a gravity sewer that followed a pressure sewer were studied. The primary focus was on changes in chemical oxygen demand (COD) components during transport, which were investigated using oxygen uptake rate measurements and volatile fatty acid analyses. Sulfide formation in the pressure sewers and sulfide oxidation in the gravity sewer were also studied. Anaerobic hydrolysis, which resulted in a net production of readily biodegradable substrate in the pressure sewers, was quantified. A process model description, which included the main aerobic and anaerobic processes in the water phase and in the biofilm, was presented; model parameters were determined based on calibration. This simulation procedure made it possible to consider integrated aspects of hydrogen sulfide and variations in COD components in sewers such as odor and sewer corrosion by hydrogen sulfide and the inadequacy of advanced wastewater treatment because of the input of low‐quality wastewater. It is possible to include wastewater quality changes and, thereby, process aspects for sewer design and operation.
Biosolids‐Amended Soils: Part II. Chemical Lability as a Measure of Contaminant Bioaccessability
Authors: Schwab A. P. , Lewis K. , Banks M. K.
Published: October 2006

Biosolids recycling by amending agricultural soils has increased significantly over the last few decades. The presence of contaminants in small, bioavailable quantities has generated concerns about health threats resulting from accumulation of potential toxins in the food chain. In this study, land application of biosolids was evaluated for environmental risk. Chemical lability tests for metals were used for the test soils and included analyses for water soluble, exchangeable, and metals extractable by the physiologically based extraction test. Chemical extractions detected slight increases in labile metal concentrations for many of the treated soils, particularly those receiving long‐term applications of 5 years or more. Significantly higher metal concentrations were observed in the soils that had been exposed to biosolids before the U.S. Environmental Protection Agency (Washington, D.C.) 503 Rule (U.S. EPA, 2004) was implemented.
Earwitness identification performance: the effect of language, target, deliberate strategies and indirect measures
Authors: Philippon Axelle C. , Cherryman Julie , Bull Ray , Vrij Aldert
Published: October 2006

The present study examined whether voice identification performance is influenced by language comprehension (i.e. familiar vs. non‐familiar language) and target presence (target‐present (TP) vs. target‐absent line‐ups (TA)). It also looked at the relationship of deliberate strategies and indirect measures (i.e. confidence, difficulty and pressure) with performance. Sixty Native English speakers were exposed to an auditory event involving 45 to 50 seconds of speech. After 30 minutes delay, participants listened to a voice line‐up (TP or TA) in either a familiar (i.e. English) or unfamiliar language (i.e. French) according to the language spoken during the event, and were then asked to identify the original speaker's voice. Participants demonstrated significantly better performance for the familiar language/TP line‐ups. Participants who reported using the ‘elimination’ strategy were significantly more accurate than participants who reported using either a ‘matching’ strategy or no strategy. Indirect measures were not found to be good predictors of performance, except for confidence regarding TA accuracy. Copyright © 2006 John Wiley & Sons, Ltd.
The impact of experienced versus non‐experienced suggestions on children's recall of repeated events
Authors: Powell Martine B. , Roberts Kim P. , Thomson Donald M. , Ceci Stephen J.
Published: October 2006

Three experiments were conducted to test the proposition that children's suggestibility about an occurrence of a repeated event is heightened when an interviewer suggests false details that were experienced in non‐target occurrences of the event as opposed to new details that never occurred. In each experiment, children participated in a repeated event during which specific items varied each time (e.g. the children always got a sticker but the theme of the sticker was different in each occurrence). Separate biasing and memory interviews were then conducted. In Experiment 1, the interviewer merely suggested that the false details might have occurred in the event. In the remaining experiments, the suggested details were clearly linked to the target occurrence with either a contextual or temporal cue. The potential moderating effect of the child's age (Experiment 1) and the retention interval (Experiments 1 and 2) were also examined. Consistent with the initial hypothesis, suggestions about experienced (non‐target) details were more likely to be repeated by the children compared to suggestions about non‐experienced details. In Experiments 2 and 3, experienced suggestions were also more likely to inhibit children's recall of the target occurrence. The relevance and generalizability of these findings to the legal setting are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
“Pocket Dendrimers” as Nanoscale Receptors for Bimolecular Guest Accommodation
Authors: Shinoda Satoshi , Ohashi Masakazu , Tsukube Hiroshi
Published: October 2006

A new series of dendrimer receptors was prepared by combining a (tetraphenylporphinato)zinc(II) core and benzyl ether type dendritic substituents. Since one direction of the (tetraphenylporphinato)zinc(II) was not substituted by a dendritic residue, the resulting unsymmetrical dendrimers have “pockets” available for access of external substrates. Molecular modeling, NMR measurements, and zinc‐coordination experiments revealed that the third‐generation dendrimer of this type exhibited characteristic inclusion of coordinative pyridine guests. When diamidopyridine moiety was introduced into the dendrimer pocket, a thymine derivative was bound through complementary hydrogen bonding. Two different kinds of substrates, pyridine and thymine derivatives, were simultaneously accommodated in the nanoscale pocket and bimolecular guest accommodation was realized with the designed dendrimer receptor.
Myosin16b: The COOH‐tail region directs localization to the nucleus and overexpression delays S‐phase progression
Authors: Cameron Richard S. , Liu Changdan , Mixon April S. , Pihkala Jeanene P. S. , Rahn Rebecca J. , Cameron Patricia L.
Published: October 2006

Rat Myo16a and Myo16b comprise the founding members of class XVI myosin and are characterized by an N‐terminal ankyrin repeat domain thought to mediate an association with protein phosphatase 1 catalytic subunits 1α and 1γ. Myo16b is the principal isoform and reveals predominant expression in developing neural tissue. Here, we use COS‐7 cells as a model system to develop an understanding of Myo16b function. We find that Myo16b displays predominant localization in the nucleus of cells transitioning through interphase, but is not associated with processes of mitosis. Using a panel of EGFP‐Myo16b‐expression plasmids in transient transfection studies, we identified the COOH‐terminal residues 1616–1912 as necessary and solely sufficient to target Myo16b to the nucleus. We show that the Myo16b‐tail region directs localization to a nuclear compartment containing profilin and polymerized actin, which appears to form a three‐dimensional meshwork through the depth of the nucleus. Further, we demonstrate that this compartment localizes within euchromatic regions of the genome and contains proliferating cell nuclear antigen (PCNA) and cyclin A, both markers of S‐phase of the cell cycle. Cells transiently expressing Myo16b or Myo16b‐tail region show limited incorporation of BrdU, delayed progression through S‐phase of the cell cycle, and curtailed cellular proliferation. Cell Motil. Cytoskeleton 2006. © 2006 Wiley‐Liss, Inc.
Periventricular efferent neurons in the optic tectum of rainbow trout
Authors: Kinoshita Masae , Ito Etsuro , Urano Akihisa , Ito Hironobu , Yamamoto Naoyuki
Published: October 2006

The efferent connections and axonal and dendritic morphologies of periventricular neurons were examined in the optic tectum of rainbow trout to classify periventricular efferent neurons in salmonids. Among the target nuclei of tectal efferents, tracer injections to the following four structures labeled periventricular neurons: the area pretectalis pars dorsalis (APd), nucleus pretectalis superficialis pars magnocellularis (PSm), nucleus ventrolateralis of torus semicircularis (TS), and nucleus isthmi (NI). Two types of periventricular neurons were labeled by injections to the APd. One of them had an apical dendrite ramifying at the stratum fibrosum et griseum superficiale (SFGS), with an axon that bifurcated into two branches at the stratum griseum centrale (SGC), and the other had an apical dendrite ramifying at the SGC. Two types of periventricular neurons were labeled after injections to the TS. One of them had an apical dendrite ramifying at the boundary between the stratum opticum (SO) and the SFGS, and the other had dendritic branches restricted to the stratum album centrale or stratum periventriculare. Injections to the PSm and NI labeled periventricular neurons of the same type with an apical dendrite ramifying at the SO and a characteristic axon that split into superficial and deep branches projecting to the PSm and NI, respectively. This cell type also possessed axonal branches that terminated within the tectum. These results indicate that periventricular efferent neurons can be classified into at least five types that possess type‐specific axonal and dendritic morphologies. We also describe other tectal neurons labeled by the present injections. J. Comp. Neurol. 499:546–564, 2006. © 2006 Wiley‐Liss, Inc.
Distribution and differentiation of microglia in the human encephalon during the first two trimesters of gestation
Authors: Monier Anne , Evrard Philippe , Gressens Pierre , Verney Catherine
Published: October 2006

We describe the topographical distribution of microglial subpopulations during development of the human diencephalon and telencephalon. Brains from embryos and fetuses age 5–23.5 gestational weeks (gw) were subjected to single‐ and double‐immunolabeling for lectin RCA‐1 (Ricinus Communis Agglutinin 1), Iba1 (a microglial marker), CD68 (specific of macrophages), CD45 (marker for mononucleate cells of hematopoietic lineage), CD34 (expressed on endothelial cells), and MIB1 and Ki67 (markers for cell proliferation). At 5.5 gw the first intracerebral microglial cells were seen close to the meninges and choroid plexus near the di‐telencephalic fissure. They were amoeboid and positive for Iba1, CD45, and RCA‐1, whereas cells in the deep parenchyma expressed Iba1/CD68/RCA‐1 and constituted clusters. In the developing diencephalon, microglial clusters were located in junctional regions of the white matter anlagen, most notably at the junctions of the internal capsule with the thalamic projections, the external capsule, and the cerebral peduncle. In the cortical anlagen, Iba1+/RCA‐1/CD68+/CD45+ cells accumulated at 10–12 gw, constituting a tangential band at the junction between the cortical plate and the subplate. Between 10 and 16 gw microglial clusters increased markedly in size and cellular density. Contact between Iba1+ microglia and CD34+ blood vessels was clearly visible from 10–12 gw onward, first in microglial clusters of the white matter anlagen and subsequently throughout the parenchyma. From the middle of the second trimester onward microglial cells colonized the entire cerebral parenchyma, developed a ramified morphology, and downregulated their surface antigens, but remained more numerous in the white matter. J. Comp. Neurol. 499:565–582, 2006. © 2006 Wiley‐Liss, Inc.