bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Structure of Dicyclohexylammonium Tri‐tert‐pentoxysilanethiolate and 5‐Aminopentylammonium Tri‐tert‐pentoxysilanethiolate
Authors: Baranowska K. , Chojnacki J. , Gosiewska M. , Wojnowski W. 
Published: May 2006

AbstractTri–tert–pentoxysilanethiol, (EtMe2CO)3SiSH, reacts with dicyclohexylamine and 1,5–diaminopentane yielding ion‐quadruples connected by hydrogen bonds: [{(C6H11)2NH2}+{(EtMe2CO)3SiS}−]2 (1) and [{H2N–C5H10–NH3}+{(EtMe2CO)3SiS}−]2 (2). The compounds were characterized by X–ray diffraction, elemental analysis, IR and NMR. Both compounds form dimers, composed of two thiolate anions and two ammonium cations. The dimers have a central core of eight–membered rings built due to the formation of four charge–assisted N+–H···−S–hydrogen bonds. Additional N+–H···N hydrogen bonds are found in the case of 2, linking the dimers into infinite two–dimensional sheets.
Synthese eines funktionalen Aluminiumalkinids, Me3C‐C≡C‐AlBr2, und dessen Reaktionen mit der sperrigen Lithiumverbindung LiCH(SiMe3)2
Authors: Uhl Werner , Er Elif , Matar Madhat 
Published: May 2006

AbstractSynthesis of a Functional Aluminium Alkynide, Me3C‐C≡C‐AlBr2, and its Reactions with the Bulky Lithium Compound LiCH(SiMe3)2Treatment of aluminium tribromide with the lithium alkynide (Li)C≡C‐CMe3 afforded the aluminium alkynide Me3C‐C≡C‐AlBr2 (1) in an almost quantitative yield. 1 crystallizes with trimeric formula units possessing Al3C3 heterocycles and the anionic carbon atoms of the alkynido groups in the bridging positions. A dynamic equilibrium was determined in solution which probably comprises trimeric and dimeric formula units. Reaction of 1 with one equivalent of LiCH(SiMe3)2 yielded the compound [Me3C‐C≡C‐Al(Br)‐CH(SiMe3)2]2 (2), which is a dimer via Al‐C‐Al bridges. Two equivalents of the lithium compound gave a mixture of four main‐products, which could be identified as 2, Li[Me3C‐C≡C‐Al{CH(SiMe3)2}3] (3), Me3C‐C≡C‐Al[CH(SiMe3)2]2 (4), and Al[CH(SiMe3)2]3. The lithium atom of 3 is coordinated by the C≡C triple bond and an inner carbon atom of one bis(trimethylsilyl)methyl group. Further interactions were observed to C‐H bonds of methyl groups.
Altering the Activity of Catechol Oxidase Model Compounds by Electronic Influence on the Copper Core
Authors: Anekwe Johnson , Hammerschmidt Adrienne , Rompel Annette , Krebs Bernt 
Published: May 2006

AbstractThe catecholase activity of the dicopper(II) complexes [Cu2(L1)(μ‐OCH3)(NCCH3)2](PF6)2·H2O·CH3CN (1), [Cu2(L2)(μ‐OH)(MeOH)(NCCH3)](BF4)2 (2), [Cu2(L3)(μ‐OMe)(NCCH3)2](BF4)2·2CH3CN·H2O (3), [Cu2(L2)(μ‐OAc)2]BF4·H2O (4), [Cu2(L4)(μ‐OAc)2]ClO4 (5) and [Cu2(L5)(μ‐OMe)(NCCH3)3(OH2)](ClO4)2·2CH3OH·CH3CN (6) consisting of varying para‐substituted phenol ligands HL1 = 4‐trifluoromethyl‐2,6‐bis((4‐methylpiperazin‐1‐yl)methyl)phenol, HL2 = 4‐bromo‐2,6‐bis((4‐methyl‐1,4‐diazepan‐1‐yl)methyl)phenol, HL3 = 4‐bromo‐2‐((4‐methyl‐1,4‐diazepan‐1‐yl)methyl)‐6‐((4‐methylpiperazin‐1‐yl)methyl)phenol, HL4 = 2,6‐bis((4‐methylpiperazin‐1‐yl)methyl)‐4‐nitrophenol and HL5 = 4‐tert‐butyl‐2,6‐bis((4‐methylpiperazin‐1‐yl)methyl)phenol was studied. The main difference within the six complexes lies in the individual copper–copper separation that is enforced by the chelating side arms of the phenolate ligand entity and more importantly in the exogenous bridging solvent, hydroxide, methanolate or acetate ions. The distance between the copper cores varies from 2.94Å in 1 to 3.29Å in 5. The catalytic activity of the complexes 1–6 towards the oxidation of 3,5‐di‐tert‐butylcatechol was determined spectrophotometrically by monitoring the increase of the 3,5–di‐tert‐butylquinone characteristic absorption band at about 400 nm over time saturated with O2. The complexes are able to oxidize the substrate 3,5‐di‐tert‐butylcatechol to the corresponding o‐quinone with distinct catalytic activity (kcat between 92 h−1 and 189 h−1), with an order of decreasing activity 6 > 5 > 1, 2, 4 ≥ 3. A kinetic treatment of the data based on the Michaelis‐Menten approach was applied. A correlation of the catecholase activities with the variation of the para‐ substituents as well as other effects resulting from the copper core distances is discussed. [Cu2(L5)(μ‐OMe)(NCCH3)3(OH)2](ClO4)2·2CH3OH·CH3CN (6) exhibited the highest activity of the six complexes as a result of its high turnover rate.
Stapedectomy in Congenital Stapes Fixation: Are Hearing Outcomes Poorer?
Authors: Massey Becky L. , Hillman Todd A. , Shelton Clough 
Published: May 2006

OBJECTIVETo evaluate outcomes of stapedectomy surgery for congenital stapes fixation.STUDY DESIGNRetrospective chart review.METHODSThe charts of 463 stapedectomies performed by 1 surgeon from 1996 to 2003 were reviewed. Patients with a history of childhood hearing loss and operative findings consistent with congenital fixation of the stapes were included. Patients with a history of trauma or chronic otitis media and those with otosclerosis were excluded. Thirty‐six patients underwent stapedectomy for congenital fixation. Revision cases and those with inadequate postoperative bone or air conduction data were excluded. Inclusion criteria were met for 25 patients. Operative findings and hearing outcomes were evaluated.RESULTSThe study group was comprised of 25 stapedectomies. Closure of the air‐bone gap to less than 10 dB was achieved in 48% of cases, and 80% had closure within 20 dB. A gap of more than 30 dB remained in 3 cases. There were 2 cases of sensorineural hearing loss with worsening of the bone conduction thresholds by 15 dB and 30 dB. There were no instances of perilymph gusher. In addition to an excluded case that was not reconstructed because of facial nerve position, 3 of the included patients were found to have a dehiscent facial nerve at surgery. There were no facial nerve injuries, and fixation of the malleus or incus was not found in any of the included patients. When hearing outcomes were compared with our results for otosclerosis over the same time period, rates of closure to within 10 dB and 20 dB were significantly worse in the congenital group.CONCLUSIONClosure of the air‐bone gap in this population differs from our results in stapedectomy done for otosclerosis. This difference likely reflects subtle anatomic variations in the congenital group that affect the effectiveness of the prosthesis. Despite the difference in results, stapedectomy for congenital fixation remains an effective method to achieve significant hearing improvement in the majority of patients.EBM rating: B‐3b
CT‐MR Image Fusion for the Management of Skull Base Lesions
Authors: Leong Jern‐Lin , Batra Pete S. , Citardi Martin J. 
Published: May 2006

OBJECTIVEImage fusion software creates composite images from computed tomography (CT) and magnetic resonance (MR) images.STUDY DESIGN AND SETTINGCT‐MR fusion studies between August 2004 to July 2005 were reviewed. CT scan images (1‐mm axial) were obtained on a multi‐detector CT scanner. MR images (1‐mm axial) were obtained with a T1‐weighted, volume acquisition technique. CT‐MR fusion images were created on the Instatrak 3500 Plus or CBYON Suite.RESULTSA total of 25 patients had 27 CT‐MR image fusion studies. CT‐MR fusion accuracy was 2 mm or better. During preoperative planning and intraoperative navigation, CT‐MR fusion facilitated the delineation of the anatomic relationships between the lesion and the skull base.CONCLUSIONSCT‐MR image fusion yields composite images that combine features of each component imaging modality. Image fusion, when combined with surgical navigation, further enhances potential skull base applications for minimally invasive endoscopic surgery.
Intraoperative Cone‐beam CT for Guidance of Temporal Bone Surgery
Authors: Rafferty Mark A. , Siewerdsen Jeffrey H. , Chan Yvonne , Daly Michael J. , Moseley Douglas J. , Jaffray David A. , Irish Jonathan C. 
Published: May 2006

OBJECTIVESTo describe our preclinical experience with Cone Beam CT (CBCT) in image‐guided surgery of the temporal bone.STUDY DESIGN AND SETTINGSA mobile isocentric C‐arm (PowerMobil, Siemens Medical Systems, Erlangen, Germany) modified to include a flat‐panel detector (Varian Imaging Products, Palo Alto, CA) and a motorized orbit was developed to acquire multiple projections in rotation about a subject. Initial experiments imaging steel wire in air were used to investigate the system's spatial resolution in 3D image reconstruction. Subsequently temporal bone dissection was performed on five cadaver heads using the modified C‐arm as an image guidance system.RESULTSWe obtained a spatial resolution of 0.85 mm. The image acquisition time was 120 seconds and the radiation dose approximately one‐tenth of a conventional CT scan.CONCLUSIONCBCT provided submillimeter accuracy at high speed with low radiation dosage to offer utility as an intraoperative imaging system.SIGNIFICANCECBCT offers technology that approximates “near‐real‐time” image guidance.EBM rating: C‐4
Gerbilline Cholesteatoma Development Part I: Epithelial Migration Pattern and Rate on the Gerbil Tympanic Membrane: Comparisons with Human and Guinea Pig
Authors: Tinling Steven P. , Chole Richard A. 
Published: May 2006

OBJECTIVETo determine the migration rate and pattern for keratin on the tympanic membrane (TM) of the gerbil and guinea pig in comparison to human data and determine which species is an appropriate model for investigating the relationship of epithelial clearance to cholesteatoma formation.STUDY DESIGN AND SETTINGInk drops were placed on the TM and their locations plotted daily.RESULTSGerbils demonstrated a radial migration pattern away from the umbo, identical to that reported for humans, although the rate was 0.32 mm/day—3 times the human rate of 0.1 mm/day. Guinea pigs were significantly different from gerbils and humans, with a rate of 0.79 mm/day and a pattern of superior/inferior migration without anterior‐posterior movement.CONCLUSIONGerbils more closely resemble humans in rate and pattern of epithelial migration.SIGNIFICANCEGerbils represent the most appropriate model for determining the relationship between keratin migration and cholesteatoma formation.
Local Control of Murine Subglottis Development
Authors: Mankarious Leila A. , Pires Valerie L. , Rudnick Jennifer A. 
Published: May 2006

OBJECTIVETo determine if subglottic development is at least partially under local control and to determine which tissue layer(s) is predominantly responsible.DESIGNThe suglottises of 12 day‐3 CD1 mice were grown in whole organ culture. The 12 subglottises were divided into 3 individual groups: + + +, − + +, and − − −. Group + + + had all tissue layers of the subglottis intact: luminal epithelium, cricoid cartilage, inner and outer perichondrium. Group ‐ + + had all layers intact with the exception of luminal epithelium. Group − − − had all layers removed (luminal epithelium, inner and outer perichondrium) resulting in cricoid cartilage‐only rings. All rings were grown in basic medium without the use of growth factors or serum for 15 days. Measurements of the rings were taken before and after organ culture growth.RESULTSGroup +++ was the only group that experienced growth. Only luminal growth was statistically significant although all rings experienced growth in both the luminal and external diameter. Group ‐ + + did not experience any growth. Group — lost structural integrity with collapse of the ring and did not experience growth of any dimension of the cartilage.CONCLUSIONSGrowth of the subglottis is under local control but may have additional influences from the outside that were not investigated here. Removal of just the epithelium stunts growth of the entire ring, but preferentially the lumen more so than the external diameter. Removal of all tissue layers around the cricoid cartilage results in a structural collapse of the ring, suggesting that the cartilage in this age group is dependent on surrounding tissues for structural integrity.
Histopathologic Parameters as Predictors of Response to Endoscopic Sinus Surgery in Nonallergic Patients with Chronic Rhinosinusitis
Authors: Baudoin Tomislav , Čupić Hrvoje , Geber Goran , Vagić Davor , Grgić Marko , Kalogjera Livije 
Published: May 2006

OBJECTIVETo estimate the predictable value of histopathologic parameters in chronic rhinosinusitis (CRS) for response to endoscopic sinus surgery (ESS).STUDY DESIGNSymptomatology was rated in 100 patients prior to as well as 12 and 24 months after surgery. Specimens taken during the procedure were examined and scored for goblet cells, subepithelial thickening, mast cells, and eosinophils. Multiple regression analysis was performed to predict the total score of subjective symptoms before treatment by histopathologic parameters. The correlation between histopathologic parameters and postoperative symptoms was then evaluated.RESULTSGoblet cells were the best predictor correlating with 5 symptoms. Subepithelial thickening correlated with 4 symptoms. Mast cell infiltration correlated with 3 symptoms. Eosinophilic infiltration correlated with only one symptom (P < 0.05).CONCLUSIONCertain histopathologic parameters in CRS are predictive of favorable response to ESS.SIGNIFICANCEPathologic evaluation may help the ENT surgeon to predict the persistence of certain CRS symptoms after ESS, even in patients at low risk for surgical failure.EBM rating: C‐4
Improvements in Quality of Life in Children After Surgical Therapy for Sinonasal Disease
Authors: Rudnick Emily F. , Mitchell Ron B. 
Published: May 2006

OBJECTIVESTo study changes in quality of life in children with chronic sinonasal disease after surgical therapy.STUDY DESIGN AND SETTINGProspective, nonrandomized quality of life study of children with sinonasal disease who undergo adenoidectomy or functional endoscopic sinus surgery (FESS) at an academic institution. Caregivers completed a preoperative SN‐5 quality of life survey and a second survey within 6 months after surgery.RESULTSTwenty‐two children were enrolled in the study (mean, 6.5 years; range, 1.4 to 15.9). The majority (59%) of children underwent adenoidectomy. The mean total score was 25.8 at initial presentation and 12.0 at follow‐up (P > 0.001). Postoperative scores for all domains were significantly different from preoperative scores. The domains with the greatest change in mean score were nasal obstruction and emotional distress. There were no significant differences in outcome between children who underwent adenoidectomy and those who underwent FESS.CONCLUSIONSAfter either adenoidectomy or FESS, caregivers report a dramatic improvement in the quality of life of children with sinonasal disease.EBM rating: B‐3b
Modulation of Immune Mediators with MQT‐based Immunotherapy
Authors: Krouse John H. , Krouse Helene J. 
Published: May 2006

OBJECTIVEAssess immune and clinical changes with immunotherapy based on modified quantitative testing (MQT).BACKGROUNDImmunotherapy promotes immunomodulation that occurs over several years. Quantitative testing offers the advantage of initiating immunotherapy with robust antigen concentrations. This study assessed whether changes in immune mediators and allergy symptoms occur rapidly using quantitative techniques.METHODSSixteen allergic adults were tested using MQT. Subjects had serum drawn for immunoglobulins E and G4 (IgE, IgG4) to 3 antigens, Der p1, Der f1, and Fel d1, and for interleukins IL‐1β, IL‐2, IL‐4, IL‐5, IL‐10, IL‐12, and IL‐13, and IL‐1 receptor antagonist (IL‐1RA). Subjects also completed the Sino‐Nasal Outcome Test‐20 (SNOT‐20), the Allergy Outcome Scale (AOS), and the Rhinosinusitis Disability Index (RSDI). They underwent MQT‐based immunotherapy and completed outcome measures again at 6 and 12 weeks.RESULTSNine subjects completed the study. Analysis demonstrated significant increases in IgG4 levels to all antigens, significant decreases in serum levels of IL‐1β and IL‐5, and significant increases in levels of IL‐1RA. Improvement was also noted in AOS and RSDI subscales.CONCLUSIONImmunotherapy based on MQT demonstrates significant changes in immunoglobulin and cytokine levels by 12 weeks following initiation. In addition, improvement in symptom and quality‐of‐life measures occurs by 12 weeks. These findings support the rapid onset of clinical effects with MQT‐based treatment of inhalant allergy.EBM rating: C‐4
Upper respiratory tract involvement of sarcoidosis in the Turkish population
Authors: Yanardağ Halil , Enoz Murat , Papila Irfan , Uygun Sedat , Caner Metin , Karayel Tuncer 
Published: May 2006

PRINCIPLES AND METHODSUpper respiratory tract (URT) involvement is rare in sarcoidosis. In this descriptive study, we retrospectively evaluated the clinical and demographic features of 12 (2.19%) patients with URT involvement out of the 546 sarcoidosis patients with follow‐up visits at our center within the last 40‐year period.RESULTSOut of the 546 patients, 12 (2.19%) had upper respiratory tract involvement, 5 (0.91%) had laryngeal involvement, 4 (0.73%) had sinonasal tract involvement, 2 (0.36) patients had salivary gland involvement, and 1 patient had tonsillary involvement. The number of stage 0 subjects among other sarcoidosis patients was significantly lower than that among those with URT involvement.CONCLUSIONSURT involvement is rarely diagnosed in patients with systemic sarcoidosis. The most common site for URT involvement among the Turkish population is the larynx, followed by the sinonasal tract.EBM rating: C‐4
Pulmonary hypertension in patients with sickle cell disease: a longitudinal study
Authors: Ataga Kenneth I. , Moore Charity G. , Jones Susan , Olajide Oludamilola , Strayhorn Dell , Hinderliter Alan , Orringer Eugene P. 
Published: May 2006

SummaryAlthough pulmonary hypertension (PHT) is a common complication in patients with sickle cell disease (SCD), the rate of development of PHT and the factors that affect disease progression are unknown. We observed 93 patients over a median follow‐up period of 2·6 years (range 0·2–5·1 years). Data were censored at the time of death or loss to follow‐up. Pulmonary hypertension was associated with an increased risk of death (relative risk, 9·24; 95% confidence interval: 1·2–73·3; P = 0·01). There was no difference in the risk of death when patients with different degrees of PHT were compared. Lactate dehydrogenase and blood urea nitrogen were significantly associated with PHT in a logistic regression model. Higher levels of fetal haemoglobin and treatment with hydroxycarbamide were observed more frequently in patients without PHT. Thirteen per cent of patients with no previous evidence of PHT developed PHT following 3 years of observation. In conclusion: (1) PHT, regardless of severity, is associated with an increased risk of death in SCD patients; (2) haemolysis is strongly associated with PHT in SCD; (3) high levels of fetal haemoglobin and hydroxycarbamide therapy may decrease the occurrence of PHT; (4) screening for PHT is indicated for SCD patients in their non‐crisis, steady states.
Comparison of routine metabolic rates of the stygobite, Gammarus acherondytes (Amphipoda: Gammaridae) and the stygophile, Gammarus troglophilus
Authors: WILHELM FRANK M. , TAYLOR STEVEN J. , ADAMS GINNY L. 
Published: May 2006

Summary1. Reduced metabolic rate among cave organisms compared with surface species has long been suggested as an adaptation to food shortage in cave environments. However, comparisons of metabolic rates between species have not often included closely related surface and cave species. By measuring metabolic rate across three seasons and over a range of body sizes, we examined the hypothesis that the routine metabolic rate of Gammarus acherondytes, a federally listed stygobitic amphipod, is lower than that of the closely related stygophilic Gammarus troglophilus. To determine if human activities increased the supply of organic matter to caves, we also examined the relationship between residential development and bacterial contamination in water wells.2. For G. acherondytes, the slope of the overall relationship between oxygen consumption and body dry mass did not differ from zero and did not vary seasonally, whereas for G. troglophilus it was positive and higher in summer than in winter and spring. These results provide insights into a potential novel metabolic adaptation among stygobites. Higher metabolic rate in young G. acherondytes would allow efficient use of typically transient energy sources and a low metabolic rate at larger body sizes would increase survival through periods of food scarcity.3. The number of wells with faecal coliform contamination was weakly but positively correlated with the number of residential building permits, indicating that surface land‐use changes probably increase the availability of energy in groundwater systems inhabited by G. acherondytes. This may give stygophilic animals, with higher metabolic rates, a competitive advantage in the caves, thus reducing the abundance of stygobites such as G. acherondytes.
Factors influencing use of home care and nursing homes
Authors: Kim Eun‐Young , Cho Eunhee , June Kyung Ja 
Published: May 2006

Aim.  This paper reports a study comparing the characteristics of patients who use home care services and those who are cared for in nursing homes, and identifying the factors that influence the use of these care settings.Background.  The increase in the functionally dependent older population has led to an increase in the number of nursing homes and home care agencies. It has become clear that, rather than disputing which is the better of these options, it would be better to determine the characteristics of patients who use the two long‐term care services. Gaining an understanding of the unique characteristics of patients who are cared for by home care agencies and those who are cared for in nursing homes will be imperative for reforming and developing long‐term care systems.Method.  The research model was based on the Anderson Model of Health Services Utilization. Interviews were conducted with 99 stroke survivors from two home care agencies and four nursing homes, and their family members, between May and December 2001.Results.  The patient characteristics that predicted greater use of home care rather than nursing home services were: being married, poor physical function, impaired cognitive function, higher rates of comorbidity, various medical complications, and/or number of catheters (e.g. urinary catheter, naso‐gastric tube).Conclusion.  Contrary to the findings of previous studies conducted in countries with ageing populations, our findings indicate that in South Korea home care agencies, rather than nursing homes, provide care for severely impaired patients. This may be due to differences between countries in their long‐term care systems and cultural attitudes toward end‐of‐life care. Our results will contribute to the development or reformation of long‐term care systems in countries with ageing populations, and to the development of strategies for increasing access to these services.