bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fate of rigid fixation in pediatric craniofacial surgery
Authors: Berryhill Wayne E. , Rimell Frank L. , Ness John , Marentette Lawrence , Haines Stephen J. 
Published: November 2005

The advantages of rigid fixation in adult craniofacial surgery are well documented, and implanted hardware is not routinely removed unless specifically indicated. There is a tendency, however, to remove hardware in children because of concerns with growth restriction, plate migration, and the lack of information on the fate of miniplates when used in pediatric craniofacial surgery. It has been our practice during the past decade not to remove hardware in children unless specifically indicated. Our study included a total of 121 procedures in 96 children, with an average age of 3.9 years and an average follow‐up of 5 years. We placed 375 titanium plates and 1944 screws from 3 manufacturers. Complications encountered in children with titanium plates were as follows: 5 cases of delayed growth and 1 instance of restricted growth, 4 screw migrations (none intracranial), 9 palpable plates causing pain, 3 fluid accumulations over plates, 2 cases of meningitis, and 8 instances of plate and screw removal from the above complications. Twenty‐two of 96 patients (23%) had a total of 27 complications from 121 procedures (22%). There were 6 cases in which pain precipitated removal of hardware, 1 case of an excessively mobile plate, and 1 case of documented growth restriction requiring removal; therefore our overall reoperation rate for plate removal was 8%, with no intracranial plate or screw migration.
Partial Labyrinthectomy with Hearing Preservation: Frequency‐Specific Data Using Tone‐Burst Auditory Brain Stem Response
Authors: ERIC E. SMOUHA , MASAYUKI INOUYE 
Published: November 2005

Surgical approaches to the inner ear with hearing preservation have valuable implications for neurotologic surgery. In a previous study in guinea pigs, we demonstrated that click‐evoked auditory brain stem responses (ABRs) were preserved after transection and plugging of 1 or more semicircular canals but were lost after entering the vestibule (Smouha EE, et al. Otolaryngol Head Neck Surg 1996;114:777–784). A limitation of that study was that click‐evoked ABR might not represent the function of the entire cochlea. In this study we used tone‐burst ABR to determine thresholds across a broad range of frequencies (2 to 24 kHz) before and after surgical entry into the labyrinth at the lateral semicircular canal, ampulla, and vestibule. Serial measurements were made, and a sham surgery group was used as a control. The results obtained with tone‐burst ABR generally agreed with those previously obtained with click stimuli. Tone‐burst ABR thresholds were similar across most frequencies tested. Transection of the lateral semicircular canal resulted in preservation of ABR thresholds. Ampullectomy had a variable effect on ABR thresholds. Vestibulotomy usually resulted in substantial hearing loss. We conclude that hearing can be preserved across a range of frequencies after selective surgery of the inner ear. Surgical entry into the membranous labyrinth near the vestibule is the critical factor contributing to hearing loss after partial labyrinthectomy.
Validation of a Voice Outcome Survey for Unilateral Vocal Cord Paralysis
Authors: RICHARD E. GLIKLICH , ROBERT M. GLOVSKY , WILLIAM W. MONTGOMERY 
Published: November 2005

Current methods to assess voice outcomes in patients with unilateral vocal cord paralysis (UVCP) are limited by expense, reliability, or lack of a true patient‐relevant focus. The purpose of this study was to develop and validate a patient‐based, disease‐specific instrument, the Voice Outcome Survey (VOS), that is brief, reliable, and sensitive to real clinical change in patients with UVCP. Fifty‐six consecutive patients with uncompensated UVCP and without complicating comorbid illness received the VOS, the Medical Outcome Study Short Form 36‐Item Health Survey (SF‐36), and a voice laboratory analysis before and 6 months after type I thyroplasty. Overall, reliability of the VOS was excellent (r = 0.87, P< 0.0001). The VOS index was significantly (P < 0.05) correlated to subscales of the SF‐36 including social functioning (SF) (r = 0.56) and physical role functioning (r = 0.35), as well as changes in objective voice measures such as phonation time (r = 0.51) and average intensity (r = 0.44). The VOS index was the most sensitive measure to clinical change after surgery (standardized response means: VOS, 1.92; phonation time, 0.68; SF, 0.58; physical role functioning, 0.53; intensity, 0.51). The VOS is a brief, valid, reliable, and highly sensitive measure of disease‐specific health status in patients with UVCP.
Morphometric Analysis of Horizontal Canal Nerves of Chronically Diabetic Rats
Authors: MYERS STEVEN F. , TORMEY MARY C. , SUSAN AKL 
Published: November 2005

Horizontal canal nerves of 3‐, 6‐, 9‐, and 12‐month‐diabetic rats were compared with those of age‐matched controls. The myelin sheaths of the horizontal canal nerves in diabetic rats were thinner than those of age‐matched controls (mean ± SD 0.63 ± 0.04 mm [n = 16] vs. 0.71 ± 0.05 mm [n = 9]; p< 0.0001, one‐tailed t test). Regression analysis revealed that myelin sheath thickness did not correlate with severity of diabetes, but myelin thinning did occur as a function of the duration of diabetes (p < 0.05, regression ANOVA). The progression of myelin thinning over time is consistent with the possibility of an accelerated decline in vestibular function with age in diabetic patients. That myelin thinning did not correlate with the severity of diabetes suggests that this thinning is not directly related to the aging effects attributed to nonenzymatic glycosylation of myelin proteins. Multivariate analysis revealed a significant difference between diabetic and control groups when fiber diameter and intrasheath diameter were considered together (p < 0.008, canonical discriminant‐function analysis). Diabetic and control groups did not differ significantly in total nerve fiber counts. In the diabetic group, however, nerve fiber counts were higher in animals with higher blood glucose levels (p< 0.02, linear‐regression ANOVA; r2 = 0.49). The finding of higher nerve fiber counts in more severely diabetic rats is consistent with an earlier transmission electron microscopic finding of false myelinated nerve fiber profiles in micrographs from more severely diabetic rats. These false profiles are believed to represent phagocytosis‐like Schwann cell reactions against their own myelin, triggered by excess myelin glycosylation.
Tracheal Transplantation: Defining the Vascular Territory of the Canine Cranial Thyroid Artery
Authors: SHAARI CHRISTOPHER M. , GANNON PATRICK J. , SALMERON JESSE , SANDERS IRA , URKEN MARK L. 
Published: November 2005

The management of long‐segment tracheal stenosis remains an unsolved clinical problem that has significant implications for the survival of some patients and the quality of life of others. However, recent advances in microvascular tissue transfer may allow tracheal transplantation to be used as a treatment option. Studies in dogs have demonstrated that the reanastomosis of the cranial thyroid artery (CTA) after the transplantation of a short segment of trachea sustains cartilage viability. However, the distal perfusion zone of the CTA within the canine trachea has not been described. Hence it is unclear what length of trachea can be safely harvested, with use of the CTA as the donor artery, without risking ischemia of the distal trachea. This study determined the perfusion territory of the CTA by use of latex or dye infusion via the thyroid branches of the CTA. Findings in five perfusion‐fixed cadaver mongrel dogs (8 to 12 kg) were studied. In each dog, both common carotid arteries were dissected and the CTAs identified. The right CTA was ligated and the left common carotid artery was ligated cranial to the CTA. The left common carotid artery was perfused for 10 minutes under 100 mm Hg pressure with black india ink/saline solution (20:1000 ml) or with blue latex solution. Perfusion territories were determined by grossly and microscopically measuring the region of stain in the endolaryngeal and endotracheal airways. The results demonstrated that up to 18 ipsilateral rings of the canine trachea are perfused after injection of dye under physiologic pressure into the CTA. Contralateral staining was also noted, but to a lesser degree. These results suggest that the canine CTA may perfuse, on average, a 16‐ to 17‐ring tracheal segment.
Percutaneous Endoscopic Gastrostomy: Avoiding Complications
Authors: SANTOS PERRY M. , McDONALD JAMES 
Published: November 2005

This study evaluates our complications arising directly or indirectly from placement or management of percutaneous endoscopic gastrostomy (PEG) tubes and provides recommendations for avoidance of complications. Seventy‐one patients received PEG tube placement by otolaryngologists between January 1991 and May 1997. Records were reviewed for diagnoses, combined procedures, and complications. Addressing potential causes of complications prompted modification of our technique of PEG tube placement and management. Twenty‐three patients received PEG for dysphagia/aspiration unrelated to neoplasia, 11 received PEG with staging endoscopy, 11 received PEG after treatment for head and neck neoplasm, and 26 received PEG at the time of primary resection. Major complications included retained PEG hub and delayed colon abscess ultimately resulting in death. Minor complications included skin abscesses, cellulitis, and early and late vasovagal response with PEG tube removal. An airway emergency, on attempted oral airway intubation, resulted in an aborted PEG attempt and constituted another complication outside the 4 groups stated above. The major complication was not found within a literature review. We have modified our management for avoidance of this complication. We believe the causes of the minor complications have been identified, and with additional modifications in our technique, we have not had any similar complications recently. The recommended techniques are discussed in detail.
Cyclin D1 Expression as a Prognostic Parameter in Papillary Carcinoma of the Thyroid
Authors: MURO‐CACHO CARLOS A. , HOLT THOMAS , KLOTCH DOUGLAS , MORA LINDA , LIVINGSTON SANDRA , FUTRAN NEIL 
Published: November 2005

Papillary carcinoma of the thyroid is the most common thyroid cancer. At the time of clinical presentation, most papillary carcinomas are still confined to the thyroid gland, and appropriate surgical treatment achieves a 95% 5‐year survival rate. Certain carcinomas, however, behave in a much more aggressive fashion. Because specific therapies do not exist, for those tumors that have escaped local control, patients with disseminated disease have little or no chance of permanent cure or long‐term survival. Cyclin D1, a protein that plays a critical role in the control of the cell cycle, has been shown to be overexpressed in a variety of human neo‐plasias and may serve as a prognostic parameter of disease progression. To explore the role played by cyclin D1 in the pathogenesis of thyroid papillary carcinoma, we have quantitated, by computerized image analysis, the immunohistochemical expression of cyclin D1 in formalin‐fixed, paraffin‐embedded tissue from 35 conventional papillary carcinomas of the thyroid and correlated the results with established clinicopathologic parameters and available survival data.
Obstructive Sleep Apnea in Children with Achondroplasia: Surgical and Anesthetic Considerations
Authors: SISK ELIZABETH A. , HEATLEY DIANE G. , BOROWSKI BRET J. , LEVERSON GLEN E. , PAULI RICHARD M. 
Published: November 2005

OBJECTIVETo evaluate the prevalence of obstructive sleep apnea in a large population of children with achondroplasia and to evaluate the effectiveness of adenoidectomy and/or tonsillectomy as treatment.METHODSRetrospective review of 95 children with achondroplasia.RESULTSThirty‐six patients (38%) had clinical evidence of obstructive sleep apnea. Thirty‐four patients underwent surgery, with more than 1 procedure required in 10 children (29%). Adenotonsil‐lectomy was the initial procedure for 22 of 34 patients, and further therapy was required in only 18% of this group. Adenoidectomy was the initial procedure for 10 of 34, with 90% requiring further surgery for recurrent obstructive sleep apnea. Tonsillectomy alone was performed in 2 patients: 1 was effectively treated and 1 later required adenoidectomy. Endotracheal intubation was accomplished in all patients without complication; 53% required a smaller endotracheal tube than would be predicted by their age. Eight postoperative complications were recorded.CONCLUSIONSObstructive sleep apnea is very common in children with achondroplasia. Surgery is effective, but recurrent symptoms are common, particularly when the initial procedure is adenoidectomy. The complication rate is higher than that observed in a general pediatric population but is readily managed with standard therapy. Anesthesia can be given safely to these patients with special consideration for limited neck extension and appropriate endotracheal tube size.
Effects of Estrogen and Tamoxifen on Growth of Human Vestibular Schwannomas in the Nude Mouse
Authors: STIDHAM KATRINA R. , ROBERSON JOSEPH B. 
Published: November 2005

Vestibular schwannomas have been noted to have increased frequency and aggressivity in female patients, suggesting a possible role of estrogen. This study evaluated the effects of estrogen and tamoxifen on the growth of human vestibular schwannoma tissue implanted in subcutaneous pockets of nude mice. Animals were implanted with 1 of 3 human vestibular schwannomas and observed for 28 days. Mice were then separated into 3 treatment groups: controls, estrogen (receiving 1.7 mg of 17B‐estradiol), and estrogen + tamoxifen (receiving 1.7 mg of 17B‐estradiol + 10 mg of tamoxifen), and treated for 28 days. Mice treated with estrogen showed increased growth that was statistically significant (P < 0.05) when compared with that of both the controls and the animals treated with estrogen + tamoxifen. Controls and animals treated with estrogen + tamoxifen showed a general trend of decreased volume during the treatment period. These early results support the hypothesis that estrogen modulates the growth of vestibular schwannomas in the nude mouse model and that these effects can be blocked by tamoxifen administration.
A large displacement of the SXN motif of Cys115-modified penicillin-binding protein 5 from Escherichia coli
Authors: Nicola George , Fedarovich Alena , Nicholas Robert A. , Davies Christopher 
Published: November 2005

Penicillin-binding proteins (PBPs), which are the lethal targets of β-lactam antibiotics, catalyse the final stages of peptidoglycan biosynthesis of the bacterial cell wall. PBP 5 of Escherichia coli is a D-alanine CPase (carboxypeptidase) that has served as a useful model to elucidate the catalytic mechanism of low-molecular-mass PBPs. Previous studies have shown that modification of Cys115 with a variety of reagents results in a loss of CPase activity and a large decrease in the rate of deacylation of the penicilloyl–PBP 5 complex [Tamura, Imae and Strominger (1976) J. Biol. Chem. 251, 414–423; Curtis and Strominger (1978) J. Biol. Chem. 253, 2584–2588]. The crystal structure of wild-type PBP 5 in which Cys115 fortuitously had formed a covalent adduct with 2-mercaptoethanol was solved at 2.0 Å (0.2 nm) resolution, and these results provide a structural rationale for how thiol-directed reagents lower the rate of deacylation. When compared with the structure of the unmodified wild-type enzyme, a major change in the architecture of the active site is observed. The two largest differences are the disordering of a loop comprising residues 74–90 and a shift in residues 106–111, which results in the displacement of Ser110 of the SXN active-site motif. These results support the developing hypothesis that the SXN motif of PBP 5, and especially Ser110, is intimately involved in the catalytic mechanism of deacylation.
AHR1B, a new functional aryl hydrocarbon receptor in zebrafish: tandem arrangement of ahr1b and ahr2 genes
Authors: Karchner Sibel I. , Franks Diana G. , Hahn Mark E. 
Published: November 2005

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that regulates gene expression following activation by TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) or a variety of other synthetic and natural compounds. Previous studies have identified two AHR genes, AHR1 and AHR2, in zebrafish (Danio rerio), a widely used model species for studying vertebrate development and an emerging model in developmental toxicology. Zebrafish AHR2 binds TCDD with high affinity, is transcriptionally active and has a major role in mediating the developmental toxicity of TCDD. Zebrafish AHR1 lacks the ability to bind TCDD and activate transcription, and has no known function. In the present study, we report a new zebrafish AHR, designated AHR1B, which shares 34% amino acid sequence identity with AHR1 (AHR1A). The ahr1b gene resides on chromosome 22, adjacent to ahr2, whereas the ahr1a gene is located on chromosome 16. AHR1B is expressed in embryos as early as 24 hours post-fertilization and increases through the next 2 days, but expression is not inducible by TCDD. In contrast with the previously identified AHR1A, in vitro-expressed AHR1B protein exhibits specific, high-affinity binding of [3H]TCDD. Furthermore, AHR1B is able to activate the transcription of a reporter gene under the control of AHR response elements with an efficacy comparable with that of AHR2, but with a higher EC50. We speculate that AHR1B may have a physiological role, such as in embryonic development, whereas AHR2 mediates the response to xenobiotics.
Crystal structure of wild-type human thrombin in the Na+-free state
Authors: Johnson Daniel J. D. , Adams Ty E. , Li Wei , Huntington James A. 
Published: November 2005

Regulation of thrombin activity is critical for haemostasis and the prevention of thrombosis. Thrombin has several procoagulant substrates, including fibrinogen and platelet receptors, and essential cofactors for stimulating its own formation. However, thrombin is also capable of serving an anticoagulant function by activating protein C. The specificity of thrombin is primarily regulated by binding to the cofactor TM (thrombomodulin), but co-ordination of Na+ can also affect thrombin activity. The Na+-free form is often referred to as ‘slow’ because of reduced rates of cleavage of procoagulant substrates, but the slow form is still capable of rapid activation of protein C in the presence of TM. The molecular basis of the slow proteolytic activity of thrombin has remained elusive, in spite of two decades of solution studies and many published crystallographic structures. In the present paper, we report the first structure of wild-type unliganded human thrombin grown in the absence of co-ordinating Na+. The Na+-binding site is observed in a highly ordered position 6 Å (1 Å=0.1 nm) removed from that seen in the Na+-bound state. The movement of the Na+ loop results in non-catalytic hydrogen-bonding in the active site and blocking of the S1 and S2 substrate-binding pockets. Similar, if more dramatic, changes were observed in a previous structure of the constitutively slow thrombin variant E217K. The slow behaviour of thrombin in solutions devoid of Na+ can now be understood in terms of an equilibrium between an inert species, represented by the crystal structure described in the present paper, and an active form, where the addition of Na+ populates the active state.
The family feud: turning off Sp1 by Sp1-like KLF proteins
Authors: Lomberk Gwen , Urrutia Raul 
Published: November 2005

Sp1 is one of the best characterized transcriptional activators. The biological importance of Sp1 is underscored by the fact that several hundreds of genes are thought to be regulated by this protein. However, during the last 5 years, a more extended family of Sp1-like transcription factors has been identified and characterized by the presence of a conserved DNA-binding domain comprising three Krüppel-like zinc fingers. Each distinct family member differs in its ability to regulate transcription, and, as a consequence, to influence cellular processes. Specific activation and repression domains located within the N-terminal regions of these proteins are responsible for these differences by facilitating interactions with various co-activators and co-repressors. The present review primarily focuses on discussing the structural, biochemical and biological functions of the repressor members of this family of transcription factors. The existence of these transcriptional repressors provides a tightly regulated mechanism for silencing a large number of genes that are already known to be activated by Sp1.
Perceptions of speech and language therapy amongst UK school and college students: implications for recruitment
Authors: Greenwood Nan , Wright Jannet A. , Bithell Christine 
Published: November 2005

AbstractBackground: Communication disorders affect both sexes and people from all ethnic groups, but members of minority ethnic groups and males in the UK are underrepresented in the speech and language therapy profession. Research in the area of recruitment is limited, but a possible explanation is poor awareness and understanding of speech and language therapy as a profession.Aims: To investigate factors influencing attitudes to a career in speech and language therapy amongst UK school and college students focusing on the similarities and differences between males and females, and between minority ethnic and white students.Methods & Procedures: A total of 651 male and female school and college students from a range of ethnic groups and all close to selecting degree courses completed a questionnaire designed to examine the attitudes and awareness of speech and language therapy. Eleven semi‐structured follow‐up interviews were conducted to help understand the questionnaire findings. Quantitative and qualitative analyses examined differences in attitudes and the awareness of speech and language therapy amongst these groups.Outcomes & Results: Overall, one‐third of participants said they knew nothing about speech and language therapy, and males were significantly less familiar with it. Less than half the participants were aware that speech and language therapy is a degree course, and minority ethnic participants were significantly less likely to know this. Compared with males, females were almost five times as likely to say they would consider a career in speech and language therapy. Participants with relatives in health‐related jobs were significantly more likely to consider speech and language therapy than those without such relatives. Compared with white participants, minority ethnic participants said they placed greater importance on studying for a degree, a profession and a scientific career, and were more influenced by a career's prestige and a high salary.Conclusions: In order to increase the ethnic and gender diversity of speech and language therapists, the profile of the profession needs to be raised with increased awareness of the degree level courses, the scientific, evidence‐based nature of the work, and current salary scales.