bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of in vitro metabolites of rutaecarpine in rat liver microsomes using liquid chromatography/tandem mass spectrometry
Authors: Lee Sang Kyu , Lee Jaeick , Lee Eung‐Seok , Jahng Yurngdong , Kim Dong‐Hyun , Jeong Tae Cheon 
Published: April 2004

AbstractFollowing incubation of rutaecarpine, a new cyclooxygenase‐2 inhibitor, with rat liver microsomes, the structures of the metabolites were characterized by liquid chromatography with tandem mass spectrometry. Nine metabolites corresponding to mono‐ or dihydroxylated rutaecarpine were formed. Characteristic product ions for the identification of rutaecarpine metabolites were observed at m/z 136, 158 and 286. The loss of water led to the fragment ion at m/z 286, indicating the hydroxylation of the aliphatic ring. The fragment ion at m/z 136 indicated the hydroxylated form of the phenyl group of the quinazolinone moiety, while that at m/z 158 indicated the hydroxylated form of the aromatic ring of the indole moiety. Copyright © 2004 John Wiley & Sons, Ltd.
Ring contraction reactions of 2,3‐dihydro‐4H‐1,3‐oxazin‐4‐ones under electrospray ionization conditions
Authors: Ma Yuan , Liu Wei , Chen Yi , Zhao Yufen 
Published: April 2004

AbstractThe mass spectral behavior of 2,3‐dihydro‐4H‐1,3‐oxazin‐4‐ones has been investigated using electrospray ionization multi‐stage mass spectrometry (ESI‐MSn). All compounds showed a predominant retro‐Diels‐Alder (RDA) fragmentation pathway, and a novel ring contraction reaction by loss of isocynates was also found. The fragmentation mechanisms proposed for 4H‐1,3‐oxazin‐4‐ones are supported by ESI‐MS/MS/MS spectra. Copyright © 2004 John Wiley & Sons, Ltd.
The influence of electrospray deposition in matrix‐assisted laser desorption/ionization mass spectrometry sample preparation for synthetic polymers
Authors: Wetzel Stephanie J. , Guttman Charles M. , Flynn Kathleen M. 
Published: April 2004

AbstractAlthough electrospray sample deposition in matrix‐assisted laser desorption/ionization (MALDI) mass spectrometry (MS) sample preparation increases the repeatability of both the MALDI signal intensity and the measured molecular mass distribution (MMD), the electrospray sample deposition method may influence the apparent MMD of a synthetic polymer. The MMDs of three polymers of differing thermal stability, polystyrene (PS), poly(ethylene glycol) (PEG), and poly(propylene glycol) (PPG), were studied by MALDI time‐of‐flight (TOF) MS as the electrospray deposition voltage was varied. The MMDs obtained using the electrospray deposition method were compared with those obtained for hand‐spotted samples. No change was observed in the measured polymer MMD when the electrospray deposition voltage was varied in the analysis of PS, but those of PEG and PPG changed at higher electrospray voltages due to increased ion fragmentation. It was also shown that the fragmentation in the hand‐spotted samples is dependent on the matrix used in sample preparation. Copyright © 2004 John Wiley & Sons, Ltd.
The influence of mergers on firms' product‐mix strategies
Authors: Krishnan Ranjani A. , Joshi Satish , Krishnan Hema 
Published: April 2004

AbstractThis study draws on the institutional and resource‐based theories of the firm and examines whether multi‐product firms use mergers as a strategic tool to reconfigure their product‐mix toward high‐profit products. We propose that mergers facilitate product‐mix reconfiguration by relaxing institutional and organizational constraints on resource redeployment. Analysis of data from the U.S. hospital industry reveals that, relative to non‐merging hospitals, merging hospitals increased their presence in profitable, insured services but did not shift away from low‐profit services used by the uninsured. Copyright © 2004 John Wiley & Sons, Ltd.
Scalability of mobile, base‐station‐oriented RF networks
Authors: Thakkar Sohil , Chandrashekar Karthikeyan , Milner Stuart D. 
Published: April 2004

AbstractThe performance and scalability of mobile, base‐station‐oriented wireless networks with respect to routing and mobility models is addressed in this paper. Using systems‐oriented, large‐scale discrete event simulation, both performance scalability and complexity scalability are analyzed. Performance scalability addresses the effect of network size on system performance. Complexity scalability, in this case, consists of communication complexity (i.e. amount of control information exchanged to create and maintain network connectivity). Results confirmed the scalability of base‐station‐oriented networks using the routing, and mobility models, using over 2000 fully dynamic hosts and routers. Copyright © 2004 John Wiley & Sons, Ltd.
A study of dynamic addressing techniques in mobile ad hoc networks
Authors: Sun Yuan , Belding‐Royer Elizabeth M. 
Published: April 2004

AbstractDynamic address assignment enables nodes in mobile ad hoc networks to obtain a routable address without the need for any explicit configuration. It provides a means for nodes to communicate without any centralized infrastructure and provides a mechanism for dynamic network membership. Recently, a considerable number of dynamic addressing protocols have been proposed. While these approaches bear some similarities to each other, they also differ in some important characteristics. To understand the benefits of these different approaches, it is necessary to test the protocols in a wide range of network conditions so that their performance and suitability can be predicted. This paper studies existing solutions by categorizing and qualitatively analyzing the scalability and other performance properties of the approaches. We also introduce a new addressing approach that provides both quick and efficient unique address assignment. We then compare selected protocols through quantitative analysis based on extensive simulations. Based on the simulation results, we point out the applicability of the protocols and offer suggestions to improve protocol performance. Copyright © 2004 John Wiley & Sons, Ltd.
Improved capacity bounds for wireless networks
Authors: Agarwal Ashish , Kumar P. R. 
Published: April 2004

AbstractWe obtain improved upper and lower bounds on the best case and random case transport capacities of wireless networks under the Protocol Model of communication in Reference [1]. These results bracket the best case transport capacity to within a factor of $\sqrt8$ for wireless networks on a disk. This is done by identifying larger exclusion regions for receivers. The general result on exclusion regions can also be applied to arbitrary wireless footprints, including those arising from directional antennas, thus obtaining superior bounds for such technologies too. Copyright © 2004 John Wiley & Sons, Ltd.
Differential expression of cytokines in the rat heart in response to sustained volume overload
Authors: Dai R.P. , Dheen S.T. , He B.P. , Tay S.S.W. 
Published: April 2004

AbstractObjective:The present study aimed to investigate whether sustained volume overload is capable of inducing persistent upregulation of cardiac cytokines including tumor necrosis factor alpha (TNF)‐α, interleukin (IL)‐1β, interleukin (IL)‐6 and transforming growth factor (TGF)‐β1.Methods and Results:Volume overload‐induced heart hypertrophy in rats was established by aortacaval fistula, and the cardiac cytokines were measured in the myocardium from 1 to 4 weeks after operation. In the post‐fistula rats, cardiac IL‐1β and IL‐6 gene and protein levels were upregulated throughout the time of measurement. Immunohistochemistry demonstrated that IL‐1β and IL‐6 immunoreactive cells were widely distributed in the myocardium in the earlier time intervals, and mainly localized in the regions close to the endocardium in the later time intervals. The cardiac IL‐1β immunoreactive cells were mainly localized in the blood vessels whereas the IL‐6 positive cells were composed of non‐myocytes and cardiomyocytes. TGF‐β1 positive staining was increased in the myocardium up to 3 weeks after aortacaval fistula and then decreased to basal levels thereafter. In contrast to the activation of cardiac IL‐1β and IL‐6 in response to volume overload, TNF‐α expression appeared unaltered in response to sustained volume overload in the transcription and protein levels.Conclusion:The results of the present study indicate that sustained volume overload is capable of inducing persistent upregulation of some cardiac cytokines. In addition, the differential expressions of TNF‐α, IL‐1β and IL‐6 suggest that the induction of IL‐6 and IL‐1β is independent of TNF‐α mediated pathways in this animal model.
Duplication 15q14 → pter: a rare chromosomal abnormality underlying bipolar affective disorder
Authors: Reif Andreas , Kress Wolfgang , Wurm Karl , Benninghoff Jens , Pfuhlmann Bruno , Lesch Klaus-Peter 
Published: April 2004

AbstractWe have followed up a patient with 8q24.2 → qter and 15q14 → pter duplication due to a maternal reciprocal translocation, a condition related to Prader-Willi Syndrome. Apart from dysmorphic features, the patient suffered from recurring episodes of bipolar psychosis. Interestingly, PET scanning revealed revealed prominent bilateral hypometabolism in the frontal, temporal, and parietal lobes as well as in the cerebellum. Possible implications of this rare chromosomal abnormality with regards to psychiatric disorders are discussed, with emphasis on recent evidence suggesting chromosome 15q13-15 as a susceptiblity locus for psychosis.
Quality of Life in Treatment of Acute Rhinosinusitis with Clarithromycin and Amoxicillin/Clavulanate
Authors: Rechtweg Jay S. , Moinuddin Rizwan , Houser Steven M. , Mamikoglu Bulent , Corey Jacquelynne P. 
Published: April 2004

AbstractObjectives: Clarithromycin and amoxicillin/clavulanate (A/C) are first line antibiotics used to treat uncomplicated acute rhinosinusitis (ARS). This study examined the efficacy of clarithromycin and A/C for the treatment of ARS relative to the patient's quality of life (QOL).Study Design: Twenty‐two patients with uncomplicated ARS were randomly assigned treatment (single blinded relative to the investigator) using clarithromycin or A/C. Patients underwent assessment to confirm the diagnosis and treatment outcome at the initial screening and on completion of antibiotics (diagnosis + 14 days and 28 days). QOL was evaluated using the Allergy Outcomes Survey (AOS), the Rhinoconjunctivitis QOL Questionnaire (RQLQ), the Short Form 36 survey (SF‐36), an instantaneous six‐item Symptom Severity Survey (SSS‐6), and a Visual Analogue Scale (VAS). Surveys were completed at the time of diagnosis, on completion of antibiotics, and at 28 days after diagnosis.Results: Twenty patients completed the study. The SSS‐6 and the RQLQ demonstrated significant improvement for all patients at week 4 (P = .002 and P = .003, respectively). The SSS‐6 demonstrated significant improvement for clarithromycin at 14 days (P = .02) and at 28 days (P = .029), whereas A/C patients demonstrated significant improvement in symptoms only at 28 days (P = .046). The RQLQ, which reflects the previous 2 weeks, demonstrated significant improvement for the A/C patients at 28 days (P = .01). The Allergy Survey, the SF‐36, and the VAS failed to demonstrate significant improvement in the combined data analysis.Conclusions: Clarithromycin and A/C were equally effective in treating ARS. The clarithromycin patients felt better more rapidly (at 14 days), but both groups of patients had long‐term improvement in symptoms at 28 days.
Treatment of Benign Positional Vertigo in the Elderly: A Randomized Trial
Authors: Salvinelli Fabrizio , Trivelli Maurizio , Casale Manuele , Firrisi Luca , Di Peco Valerio , D'Ascanio Luca , Greco Fabio , Miele Angela , Petitti Tommaso , Bernabei Roberto 
Published: April 2004

AbstractObjectives/Hypothesis: The objective of the study was to evaluate the efficacy of three therapeutic strategies (Semont maneuver, flunarizine, and no treatment) in patients with benign paroxysmal positional vertigo.Study Design: Randomized prospective trial.Methods: One hundred fifty‐six consecutive patients older than 60 years of age who were affected by benign paroxysmal positional vertigo of the posterior semicircular canal were enrolled. The diagnosis was made on the basis of the history of recurrent sudden crisis of vertigo and positional‐induced typical nystagmus after Dix‐Hallpike positioning maneuver. Patients were randomly allocated to receive Semont liberatory maneuver (intended as a statoconia‐detachment maneuver), flunarizine, or no treatment. A post‐treatment negative Dix‐Hallpike test result was considered as a proof of vertigo resolution.Results: Cure rates with Semont maneuver were significantly higher (94.2%) than those obtained with flunarizine (57.7%) and no treatment (36.4%) (P < .001). Within a 6‐month follow‐up, relapse rates were lower among patients treated with Semont maneuver (3.8%) than those obtained with flunarizine (5.8%) and no treatment (21.1%). All patients with resolution of symptoms and negative Dix‐Hallpike test results showed a great improvement in daily activities and quality of life (P < .001).Conclusion: Semont liberatory maneuver is the most successful therapy for benign paroxysmal positional vertigo and improves patients' quality of life. Diagnostic and therapeutic maneuvers are easy to perform and should be part of the medical knowledge of every general practitioner and geriatrician.
Acute Otitis Externa: Efficacy and Tolerability of N‐Chlorotaurine, a Novel Endogenous Antiseptic Agent
Authors: Neher Andreas , Nagl Markus , Appenroth Elisabeth , Gstöttner Michaela , Wischatta Martin , Reisigl Franz , Schindler Martin , Ulmer Hanno , Stephan Kurt 
Published: April 2004

AbstractObjective: The study's objective was to test the tolerability and efficacy of the endogenous antiseptic N‐chlorotaurine (NCT) in comparison with a standard clinical treatment according to a phase IIb clinical trial protocol.Study Design: The antimicrobial agent NCT was compared with the antibiotic component drops Otosporin (containing neomycin, polymyxin B, and hydrocortisone) for topical treatment of acute otitis externa in a randomized and rater‐blinded clinical study.Methods: Fifty patients suffering from acute otitis externa were divided into two groups according to a randomized list. The test group was treated with 1 mL of 1% aqueous NCT solution, the reference group with 1 mL of Otosporin. The substances were applied to the external ear canal at one daily session until the signs of infection disappeared. Efficacy and tolerability were evaluated daily by visual analogue scale and a six‐step infection score. In addition, smears were analyzed to identify the causative pathogens.Results: Both medications were equally well tolerated by the patients. The treatment was successful for all patients of the NCT group, whereas in one patient from the reference group, the infection did not disappear. The inflammation score improved more rapidly in the NCT group, which resulted in an earlier termination of the therapy. This difference became highly significant on days 4 to 7 (P < .01 each). Time needed for disappearance of inflammation (score 0) was 5.6 ± 1.6 (mean ± SD, range 3–9) days in the NCT group and 7.4 ± 1.6 (range 4–10) days in the Otosporin group (P < .001). As expected, micro‐biologic cultures from ear swabs revealed Pseudomonas aeruginosa (58%) followed by Staphylococcus aureus (18%) as the main causative pathogens.Conclusions: NCT appears to be well tolerated and more effective than the therapy using antibiotic component drops. Because of its endogenous nature and its higher efficacy, NCT appears to be a good choice for topical treatment of acute otitis externa.
Middle Ear Pressure Changes after Nitrous Oxide Anesthesia and Its Effect on Postoperative Nausea and Vomiting
Authors: Nader Nader D. , Simpson George , Reedy Roberta L. 
Published: April 2004

AbstractObjectives/Hypothesis: This study was designed to explore the relationship between changes in middle ear pressure associated with inhalational anesthesia and the incidence of postoperative nausea and vomiting (PONV).Study Design: Prospective, randomized.Methods: Middle ear compartment pressures were measured by tympanometry in 27 randomly assigned knee arthroscopy patients throughout the surgical procedure as well as into recovery.Results: A positive correlation between the maximum positive pressure (MPP) and maximum negative pressure (MNP) gradient and PONV was demonstrated (P < .05). The incidence of PONV in the nitrous oxide (N2O) treatment group was 6 of 16 patients, whereas only 2 of 11 patients in the control group developed nausea, vomiting, and vertigo symptoms. Those patients that did not experience PONV demonstrated a median MPP of 155 with a median MNP of −52. The patients that experienced PONV exhibited a median MPP of 179 with a median MNP of −164. This demonstrates a significant increase in the incidence of PONV in the N2O treatment group.Conclusions: Barometric changes in the middle ear contribute to the incidence of PONV induced by N2O.
Squamous Cell Carcinoma of the Oral Tongue in Young Patients
Authors: Popovtzer Aron , Shpitzer Thomas , Bahar Gideon , Marshak Gideon , Ulanovski David , Feinmesser Raphael 
Published: April 2004

AbstractObjectives/Hypothesis: Cancer of the tongue is reported with increasing frequency in young people. The objective of this work was to study the biologic and clinical course of the disease in this group. The clinical course of the disease in this patient group remains controversial.Study Design: A retrospective 30‐year review was made from data from a tertiary academic medical center.Methods: A chart review was performed for 48 patients with oral tongue cancer. The following variables were compared: age, sex, tobacco and alcohol use, treatment, and outcome.Results: Stage (T1,2‐N0) and treatment modality were similar in the two age groups, as was disease‐specific outcome. However, in the younger group, the clinical course followed two distinct patterns: extremely aggressive appearance with a 40% mortality rate within 2 years compared with 10.7% in the older group (P < .05) or indolent with freedom from disease for over 15 years.Conclusions: Squamous cell carcinoma (SCC) of the oral tongue may be associated with a variable clinical course in younger patients. Although, in general, the disease‐specific outcome is similar to that of the older patients, some of the patients have an exceptionally aggressive disease. An extensive therapeutic regimen should be used in all cases.
Incidence of Methicillin‐Resistant Staphylococcus aureus Causing Chronic Rhinosinusitis
Authors: Manarey Casey R. A. , Anand Vijay K. , Huang Clark 
Published: April 2004

AbstractObjective/Hypothesis: To identify the incidence of methicillin‐resistant Staphylococcus aureus (MRSA) causing chronic rhinosinusitis (CRS) and identify whether antibiotic use and previous endoscopic sinus surgeries (ESS) contribute to its development.Study Design: A retrospective case control analysis, with the control group randomly selected and matched for age and sex.Methods: All patients undergoing an endonasal culture in a tertiary otolaryngology center between April 2001 and March 2003 for mucopurulent rhinosinusitis were identified. A chart review was undertaken to identify those patients with a positive MRSA culture result. An age‐ and sex‐matched control group was randomly chosen, and an interview was conducted to identify antibiotic use and previous ESS. A statistical analysis on these two variables was carried out using a t test and the Wilcoxon rank‐sum test.Results: Two hundred eighty cultures were identified in 188 patients, and of these, 264 cultures in 173 patients met the inclusion criteria. There were 141 positive cultures and 13 positive MRSA cultures. The overall incidence of MRSA in this population was 9.22%. The mean number of antibiotic courses in the MRSA and the control groups was 33.2 and 26.7, respectively, which was not statistically significant (P = .43). The 95% confidence interval (CI) for this mean difference of 6.5 is −9.8 to 22.8. The mean number of ESS in the MRSA and control groups was 2.0 and 1.9, respectively, which was not statistically significant (P = .93). The 95% CI for this mean difference of 0.06 is −1.3 to 1.4.Conclusions: We identified a 9.22% incidence of MRSA‐causing CRS. The frequency of antibiotic use and previous ESS were found not to be statistically significant causes of MRSA sinusitis. However, the 95% CI for antibiotic usage is skewed to the right, indicating a possible role for its contribution to the emergence of MRSA‐causing CRS.
Portfolio of health advice for young people with disabilities transferring to adult care
Authors: Tan M. J. , Klimach V. J. 
Published: April 2004

AbstractBackground  The transition from paediatric to adult services for young people with complex disabilities is fraught with anxieties for families. To facilitate the transition process a portfolio comprising reports from parents, paediatrician and therapists was collected and given to the young person and family on leaving school.Aim  To evaluate the young people and their parents’ views of the usefulness of portfolios in providing comprehensive picture of their health needs.Methods  A prospective study was performed. Eight families were interviewed and semi‐quantitative feedback obtained using standardized questionnaires.Results  Seven out of eight young people and their families were satisfied with the portfolios they received. All of them found the portfolios worthwhile and useful. A quarter of the families would like to have been consulted more about the content of the individual reports.Conclusions  Portfolios of health reports facilitate transfer of information when young people with disabilities move from paediatric to adult services. Ideally portfolios should be interagency, and include reports from education and social services.
Different meanings of respite: a study of parents, nurses and social workers caring for children with complex needs
Authors: MacDonald H. , Callery P. 
Published: April 2004

AbstractAim  To examine the meaning of respite care to parents of children with complex conditions and providers.Methods  In‐depth interviews, participant observation and document review were used to collect data from nineteen mothers and seven fathers of children between the ages of 8 and 16 years who required complex care and from their respite providers, including thirteen nurses, and four social workers from three counties in North‐west England.Results  Parents described three categories of respite: short breaks provided by the extended family or friends, short breaks (3–4 h) by an outside agency, and overnight respite outside of home. They highly valued overnight respite outside the home. There was some overlap but also notable differences between parents’ and providers’ categorizations of respite care and the value attached to different forms of respite provision. Parents and nurses valued overnight respite outside the home unlike social workers who preferred to provide respite without separating children from their families.Discussion  Appropriate provision of respite care and communication with parents requires understanding of the meaning of respite to parents. The meanings attached to respite care by parents and providers should be considered in attempts to understand and address problems of inappropriate provision and/or dissatisfaction with respite services.