bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tracheotomy in Very Low Birth Weight Neonates: Indications and Outcomes
Authors: Sisk Elizabeth A. , Kim Theresa B. , Schumacher Robert , Dechert Ronald , Driver Lynn , Ramsey Ann Marie , Lesperance Marci M. 
Published: June 2006

AbstractObjective/Hypothesis: To review incidence of, indications for, and outcomes of tracheotomy in very low birth weight (VLBW) infants.Study Design: Retrospective review in tertiary care hospital.Methods: Eighteen VLBW (<1,500 g) infants with bronchopulmonary dysplasia undergoing tracheotomy in the neonatal intensive care unit between October 1997 and June 2002 were studied. Controls consisted of 36 VLBW infants undergoing intubation without tracheotomy, two per study infant, matched by gestational age and weight. Outcome measures included duration and number of intubation events, time to decannulation, complications, comorbidities, length of stay, and speech, language, and swallowing measures.Results: Infants undergoing tracheotomy had an average duration of intubation of 128.8 days with a median number of 11.5 intubation events, both significantly greater than those of controls. Percentage of those with laryngotracheal stenosis was 44% of study infants had laryngotracheal stenosis compared to 1.6% in all intubated VLBW infants. The tracheotomy group had a significantly higher incidence of gastroesophageal reflux, pulmonary hypertension, and gastrostomy tube placement. The overall tracheotomy‐related complication rate was 38.9%. Three were lost to follow‐up, and five deaths occurred, two possibly tracheotomy‐related. Six of ten were decannulated by an average time of 3.8 years, two of six after laryngotracheal reconstruction. Four of ten remained cannulated for a variety of reasons. Disorders of speech, language, and swallowing were common.Conclusions: When considering tracheotomy in VLBW infants, the total number of intubation events should be monitored as well as the total duration of intubation. The relatively high incidence of laryngotracheal stenosis argues for earlier endoscopy and possibly earlier tracheotomy in infants with developing stenoses.
Does the Severity of Obstructive Sleep Apnea Predict Patients Requiring High Continuous Positive Airway Pressure?
Authors: Oksenberg Arie , Arons Elena , Froom Paul 
Published: June 2006

AbstractStudy Objectives: To investigate polysomnographic and anthropomorphic factors predicting need of high optimal continuous positive airway pressure (CPAP).Design: Retrospective data analysis.Patients: Three hundred fifty‐three consecutive obstructive sleep apnea (OSA) patients who had a successful manual CPAP titration in our sleep disorders unit.Measurements and Results: The mean optimal CPAP was 9.5 ± 2.4 cm H2O. The optimal CPAP pressure increases with an increase in OSA severity from 7.79 ± 2.2 in the mild, to 8.7 ± 1.8 in the moderate, and to 10.1 ± 2.3 cm H2O in the severe OSA group. A high CPAP was defined as the mean + 1 standard deviation (SD; ≥12 cm H2O). The predictor variables included apnea‐hypopnea index (AHI), age, sex, body mass index (BMI), Epworth Sleepiness Scale (ESS), and the Multiple Sleep Latency Test (MSLT). High CPAP was required in 2 (6.9%), 6 (5.8%), and 63 (28.6%) patients with mild, moderate, and severe OSA, respectively. On univariate analysis, AHI, BMI, ESS score, and the proportion of males were significantly higher in those needing high CPAP. They also have a lower MSLT mean. On logistic regression, the use of high CPAP was 5.90 times more frequent (95% confidence interval 2.67–13.1) in severe OSA patients after adjustment for the other variables. The area under the receiver operator curve was 72.4%, showing that the model was adequate.Conclusions: Severe OSA patients are much more likely to need high CPAP levels. However, because of the low positive predictive value (only 28.6%), the clinical value of such information is limited. ESS and MSLT did not increase the predictive value for the need for high CPAP.
Sleep‐Disordered Breathing in Children: Survey of Current Practice
Authors: Mitchell Ron B. , Pereira Kevin D. , Friedman Norman R. 
Published: June 2006

AbstractObjectives: The American Academy of Pediatrics recommends objective testing with polysomnography (PSG) before adenotonsillectomy for sleep‐disordered breathing (SDB) in children. Several studies have also shown that a clinical diagnosis correlates poorly with the presence or severity of SDB as confirmed by PSG. The purpose of this study was to examine surgical practice patterns among members of the American Society of Pediatric Otolaryngologists (ASPO).Methods: A questionnaire was sent electronically to all members of ASPO asking about demographics, PSG facilities, and pre‐ and postoperative management of children with SDB.Results: A total of 245 questionnaires were sent, and 105 (43%) were completed. The results of the survey show that up to 50% of pediatric visits in individual practices were for SDB. Only 10% of children who underwent adenotonsillectomy had PSG, and the most common reason to request it was doubt about diagnosis. The average wait for PSG was 3 to 6 weeks. Preoperative PSG was routinely requested in children under 1 year of age and children with morbid obesity, craniofacial abnormalities, or neuromuscular disease. The majority of pediatric otolaryngologists proceeded with an adenotonsillectomy in symptomatic children with normal PSG findings. Postoperative PSG was requested in less than 5% of children. Approximately 20% of children who underwent adenotonsillectomy for suspected SDB were observed overnight in hospital.Conclusions: A majority of respondents from this survey rely on a clinical diagnosis rather than PSG to recommend an adenotonsillectomy for SDB in children. PSG was generally used when the diagnosis was in doubt.
Metrics of Nasal Tip Rotation: A Comparative Analysis
Authors: Kim David W. , Egan Kristin K. 
Published: June 2006

AbstractObjective: We introduce a new metric for measuring nasal tip rotation, the “columellar facial angle.” The present study aimed to determine the degree of correlation of the nasolabial angle, the nostril axis, and the columellar–facial angle as metrics of nasal tip rotation in healthy volunteers. The study also aimed to identify any nasal or facial features unrelated to tip position, which consistently altered these values.Methods: Lateral photographs in the Frankfort horizontal plane were taken of 100 volunteers. Measurements of tip rotation were then calculated for each model using three different methods: nasolabial angle, nostril axis, and columellar–facial angle. Data were analyzed for degree of correlation of the three values for all models. Facial features in those subjects with low correlation between measurement methods were analyzed.Results: For all grouped data, both the nasolabial angle and the nostril axis showed moderate correlations with columellar facial angle but no correlation with each other. Individual subjects whose measurements did not correlate tended to display certain anatomic features: premaxillary deficiency, premaxillary excess, sloped upper lips, or vertical malposition of the nostrils.Conclusions: No one method of measurement of nasal tip rotation is reliable for all patients. Certain nasal and facial features are likely to alter these values. Of the three measurement methods presented, the columellar–facial angle is most likely to yield consistent measurements of nasal tip rotation.
Otoacoustic Emissions and Persistent Tinnitus after Acute Acoustic Trauma
Authors: Nottet Jean‐Bertrand , Moulin Annie , Brossard Nicolas , Suc Benoît , Job Agnès 
Published: June 2006

AbstractObjectives: To follow up the auditory status of military personnel after an acute acoustic trauma and to identify the possible predictive value of hearing thresholds and otoacoustic emissions during the first 24 hours after the acoustic trauma.Study Design: A group of 24 young military subjects, aged 22 ± 2.3 years, without any otologic problem before the acoustic trauma, were examined at three time intervals after an accidental acoustic trauma caused by the discharge of a firearm: 24 hours, 72 hours, and 15 days.Methods: Each subject was submitted to medical examination and to a questionnaire detailing the circumstances of the acoustic trauma. Pure tone audiometry was performed from 1 to 8 kHz per half octave. Transiently evoked otoacoustic emissions were recorded in the nonlinear mode at 80 dB pSPL, and distortion product otoacoustic emissions were recorded from 1 to 6 kHz, using a distortion product‐gram type procedure, at 65/55 dB SPL, with f2/f1 = 1.22. Two groups of subjects were defined: group 1 (n = 8) represented subjects with short‐lasting tinnitus (<72 h) and group 2 (n = 16) subjects with long‐lasting tinnitus (>72 h).Results: Hearing thresholds did not differ significantly between these two groups 24 hours after the acoustic trauma. However, otoacoustic emissions showed significantly lower amplitudes 24 hours after the acoustic trauma in subjects showing a longer lasting tinnitus.Conclusion: Otoacoustic emissions appear to be a better predictor of the persistence of tinnitus than hearing thresholds alone 24 hours after an acute acoustic trauma.
Standardization of Free Jejunum Transfer After Total Pharyngolaryngoesophagectomy
Authors: Sarukawa Shunji , Sakuraba Minoru , Kimata Yoshihiro , Yasumura Tsuneo , Uchiyama Kiyotaka , Hishinuma Shigeyuki , Nakatsuka Takashi , Hayashi Ryuichi , Ebihara Satoshi , Harii Kiyonori 
Published: June 2006

AbstractObjective: Our latest free jejunum transfer procedure was reviewed and compared with previous procedures to standardize the operation.Methods: This was a retrospective study of 269 patients who had undergone total pharyngolaryngoesophagectomy and free jejunum transfer from 1992 through 2004. The patients were divided into two groups: a late group, in which surgery was performed with our latest standard procedure from 2000 through 2004, and an early group, in which various procedures had been used from 1992 through 1999. Surgical times, postoperative progress, and complications were evaluated.Results: The mean surgical time was shortened from 3 hours 25 minutes in the early group to 3 hours 9 minutes in the late group, and ischemic time was shortened from 2 hours 44 minutes to 2 hours 20 minutes. For recipient vessels, branches of the external carotid artery and the internal jugular vein were more often used in the late group. Length of hospitalization decreased from 31.7 days in the early group to 24.4 days in the late group, although the start of drinking was similar (15.4 days versus 12.1 days). The rates of complications were significantly reduced in the late group, particularly those associated with the enteric anastomosis such as minor leakage (18.2–5.2%) and stenosis (17.6–3.0%).Conclusion: Our latest method of free jejunum transfer reconstruction has become reliable and expeditious through simple and stable minor revisions of procedures.
Enophthalmos as a Complication of Rhinoplasty
Authors: Eloy Jean Anderson , Jacobson Adam Saul , Elahi Ebrahim , Shohet Michael Robert 
Published: June 2006

AbstractSilent sinus syndrome is a known clinical entity caused by negative sinus pressure from acquired obstruction of the maxillary sinus ostium with resulting enophthalmos and hypoglobus. We present a case in which, after septorhinoplasty, a patient developed progressive enophthalmos and hypoglobus. His evaluation was consistent with silent sinus syndrome. This case illustrates the complex reconstructive challenges of repairing an orbit in the setting of fistulization of the orbit with the maxillary sinus cavity. In particular, we highlight the inferior fornyx transconjunctival approach with simultaneous intranasal endoscopic maxillary sinus aeration.
Retronasal and Orthonasal Olfactory Function in Relation to Olfactory Bulb Volume in Patients With Posttraumatic Loss of Smell
Authors: Rombaux Philippe , Mouraux André , Bertrand Bernard , Nicolas Georges , Duprez Thierry , Hummel Thomas 
Published: June 2006

AbstractObjective: The aims of this study were to evaluate olfactory function with orthonasal and retronasal testing in patients with posttraumatic olfactory loss and to investigate the relation between residual olfactory function and olfactory bulb (OB) volume.Method: A retrospective study of 25 patients with posttraumatic olfactory loss was performed. Orthonasal olfactory function was assessed with the Sniffin' Sticks test kit; retronasal olfactory function was assessed with intraorally applied odors. Magnetic resonance imaging was used to determine OB volume and cortical damage in the frontal and temporal areas.Results: The main outcomes of the present study were the demonstration of a correlation between olfactory function and OB volume, which was more pronounced for retronasal than for orthonasal olfactory function; retronasal olfactory function was most affected in the patients with the most extensive cerebral damage and was least compromised in patients without such damage; OB volumes were smaller in patients with parosmia compared with those without; and the presence of parosmia was clearly associated with the presence of cerebral damage.Conclusion: The data confirm that OB volume is an indicator of olfactory function but, interestingly, in this study, it is largely determined by retronasal olfactory sensitivity. In addition, these results emphasize the role of higher cortical centers in olfactory function, and especially in parosmia, which may, at least in some cases, be related to lesions in the fronto‐orbital and anterior temporal cortices. It would be of interest to investigate OB volume further in relation to the prognosis of the disorder.
Functional Outcomes after CO2 Laser Treatment of Early Glottic Carcinoma
Authors: Ledda Gian Peppino , Grover Nancy , Pundir Vishal , Masala Ernestina , Puxeddu Roberto 
Published: June 2006

AbstractObjectives: To analyze vocal outcome after endoscopic CO2 laser treatment of early glottic carcinoma by perceptive and objective assessment.Study Design: Retrospective study.Methods: Retrospective analysis of 141 consecutive patients undergoing surgery for previously untreated early glottic carcinoma between October 1993 and July 2003. Five types of laser cordectomies as classified by the European Laryngological Society classification were performed. Comparison of voice results between the different types of cordectomies as well as with a control group was performed.Results: There was no significant difference in the vocal parameters between subepithelial and subligamental cordectomies and controls (P > .05). There was, however, a significant difference between the groups of transmuscular, total, and extended cordectomies and controls (P < .05).Conclusions: Good oncologic results and vocal outcomes with no difference between controls and subepithelial and subligamental cordectomies support the use of CO2 laser endoscopic surgery as the first line of treatment for early glottic cancer.
Structure of the 21–30 fragment of amyloid β‐protein
Authors: Baumketner Andrij , Bernstein Summer L. , Wyttenbach Thomas , Lazo Noel D. , Teplow David B. , Bowers Michael T. , Shea Joan‐Emma 
Published: May 2006

AbstractFolding and self‐assembly of the 42‐residue amyloid β‐protein (Aβ) are linked to Alzheimer's disease (AD). The 21–30 region of Aβ, Aβ(21–30), is resistant to proteolysis and is believed to nucleate the folding of full‐length Aβ. The conformational space accessible to the Aβ(21–30) peptide is investigated by using replica exchange molecular dynamics simulations in explicit solvent. Conformations belonging to the global free energy minimum (the “native” state) from simulation are in good agreement with reported NMR structures. These conformations possess a bend motif spanning the central residues V24–K28. This bend is stabilized by a network of hydrogen bonds involving the side chain of residue D23 and the amide hydrogens of adjacent residues G25, S26, N27, and K28, as well as by a salt bridge formed between side chains of K28 and E22. The non‐native states of this peptide are compact and retain a native‐like bend topology. The persistence of structure in the denatured state may account for the resistance of this peptide to protease degradation and aggregation, even at elevated temperatures.
The synthesis and high‐level expression of a β2‐adrenergic receptor gene in a tetracycline‐inducible stable mammalian cell line
Authors: Chelikani Prashen , Reeves Philip J. , Rajbhandary Uttam L. , Khorana H. Gobind 
Published: May 2006

AbstractHigh‐level expression of G‐protein‐coupled receptors (GPCRs) in functional form is required for structure–function studies. The main goal of the present work was to improve expression levels of β2‐adrenergic receptor (β2‐AR) so that biophysical studies involving EPR, NMR, and crystallography can be pursued. Toward this objective, the total synthesis of a codon‐optimized hamster β2‐AR gene suitable for high‐level expression in mammalian systems has been accomplished. Transient expression of the gene in COS‐1 cells resulted in 18 ± 3 pmol β2‐AR/mg of membrane protein, as measured by saturation binding assay using the β2‐AR antagonist [3H] dihydroalprenolol. Previously, we reported the development of an HEK293S tetracycline‐inducible system for high‐level expression of rhodopsin. Here, we describe construction of β2‐AR stable cell lines using the HEK293S‐TetR‐inducible system, which, after induction, express wild‐type β2‐AR at levels of 220 ± 40 pmol/mg of membrane protein corresponding to 50 ± 8 μg/15‐cm plate. This level of expression is the highest reported so far for any wild‐type GPCR, other than rhodopsin. The yield of functional receptor using the single‐step affinity purification is 12 ± 3 μg/15‐cm plate. This level of expression now makes it feasible to pursue structure–function studies using EPR. Furthermore, scale‐up of β2‐AR expression using suspension cultures in a bioreactor should now allow production of enough β2‐AR for the application of biophysical techniques such as NMR spectroscopy and crystallography.
Molecular dissection of the mycobacterial stringent response protein Rel
Authors: Jain Vikas , Saleem‐Batcha Raspudin , China Arnab , Chatterji Dipankar 
Published: May 2006

AbstractLatency in Mycobacterium tuberculosis poses a barrier in its complete eradication. Overexpression of certain genes is one of the factors that help these bacilli survive inside the host during latency. Among these genes, rel, which leads to the expression of Rel protein, plays an important role by synthesizing the signaling molecule ppGpp using GDP and ATP as substrates, thereby changing bacterial physiology. In Gram‐negative bacteria, the protein is thought to be activated in vivo in the presence of ribosome by sensing uncharged tRNA. In the present report, we show that Rel protein from Mycobacterium smegmatis, which is highly homologous to M. tuberculosis Rel, is functional even in the absence of ribosome and uncharged tRNA. From the experiments presented here, it appears that the activity of RelMsm is regulated by the domains present at the C terminus, as the deletion of these domains results in higher synthesis activity, with little change in hydrolysis of ppGpp. However, in the presence of tRNA, though the synthesis activity of the full‐length protein increases to a certain extent, the hydrolysis activity undergoes drastic reduction. Full‐length Rel undergoes multimerization involving interchain disulfide bonds. The synthesis of pppGpp by the full‐length protein is enhanced in the reduced environment in vitro, whereas the hydrolysis activity does not change significantly. Mutations of cysteines to serines result in monomerization with a simultaneous increase in the synthesis activity. Finally, it has been possible to identify the unique cysteine, of six present in Rel, required for tRNA‐mediated synthesis of ppGpp.
Positioning of proteins in membranes: A computational approach
Authors: Lomize Andrei L. , Pogozheva Irina D. , Lomize Mikhail A. , Mosberg Henry I. 
Published: May 2006

AbstractA new computational approach has been developed to determine the spatial arrangement of proteins in membranes by minimizing their transfer energies from water to the lipid bilayer. The membrane hydrocarbon core was approximated as a planar slab of adjustable thickness with decadiene‐like interior and interfacial polarity profiles derived from published EPR studies. Applicability and accuracy of the method was verified for a set of 24 transmembrane proteins whose orientations in membranes have been studied by spin‐labeling, chemical modification, fluorescence, ATR FTIR, NMR, cryo‐microscopy, and neutron diffraction. Subsequently, the optimal rotational and translational positions were calculated for 109 transmembrane, five integral monotopic and 27 peripheral protein complexes with known 3D structures. This method can reliably distinguish transmembrane and integral monotopic proteins from water‐soluble proteins based on their transfer energies and membrane penetration depths. The accuracies of calculated hydrophobic thicknesses and tilt angles were ∼1 Å and 2°, respectively, judging from their deviations in different crystal forms of the same proteins. The hydrophobic thicknesses of transmembrane proteins ranged from 21.1 to 43.8 Å depending on the type of biological membrane, while their tilt angles with respect to the bilayer normal varied from zero in symmetric complexes to 26° in asymmetric structures. Calculated hydrophobic boundaries of proteins are located ∼5 Å lower than lipid phosphates and correspond to the zero membrane depth parameter of spin‐labeled residues. Coordinates of all studied proteins with their membrane boundaries can be found in the Orientations of Proteins in Membranes (OPM) database:http://opm.phar.umich.edu/.
Placebo‐ and paracetamol‐controlled study on the efficacy and tolerability of hyoscine butylbromide in the treatment of patients with recurrent crampy abdominal pain
Authors: MUELLER‐LISSNER S. , TYTGAT G. N. , PAULO L. G. , QUIGLEY E. M. M. , BUBECK J. , PEIL H. , SCHAEFER E. 
Published: June 2006

SummaryAimTo compare the efficacy and tolerability of oral hyoscine butylbromide (hereafter hyoscine) 10 mg t.d.s., paracetamol 500 mg t.d.s. and their fixed combination against placebo in patients with recurrent crampy abdominal pain.MethodsA total of 1637 patients were entered into a four‐arm double‐blind study. After a 1 week placebo run‐in, they were randomized to 3 weeks of treatment with one of the four therapies with assessments after 1, 2 and 3 weeks. Pain intensity (Visual Analogue Scale) and pain frequency (Verbal Rating Scale) were self‐assessed daily.ResultsPain intensity on the Visual Analogue Scale decreased in all treatment groups; the adjusted mean changes from baseline were 2.3, 2.4 and 2.4 cm for the hyoscine, paracetamol and combination groups, respectively, compared with 1.9 cm for the placebo group (all P < 0.0001). The Verbal Rating Scale also showed a statistically significant decrease of 0.7, 0.7 and 0.7 in the hyoscine, paracetamol and combination groups compared with 0.5 in placebo (all P < 0.0001). All treatments were well tolerated: 16%, 14%, 17% and 11% of patients on hyoscine, paracetamol, combination and placebo reported at least one adverse event.ConclusionsHyoscine, paracetamol and their fixed combination are effective in the treatment of recurrent crampy abdominal pain and well tolerated if used three times daily continuously for 3 weeks.