bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of peptide conformation in terms of the ABEEM/MM method
Authors: Yang Zhong‐Zhi , Zhang Qiang 
Published: October 2005

AbstractThe ABEEM/MM model (atom‐bond electronegativity equalization method fused into molecular mechanics) is applied to study of the polypeptide conformations. The Lennard–Jones and torsional parameters were optimized to be consistent with the ABEEM/MM fluctuating charge electrostatic potential. The hydrogen bond was specially treated with an electrostatic fitting function. Molecular dipole moments, dimerization energies, and hydrogen bond lengths of complexes are reasonably achieved by our model, compared to ab initio results. The ABEEM/MM fluctuating charge model reproduces both the peptide conformational energies and structures with satisfactory accuracy with low computer cost. The transferability is tested by applying the parameters of our model to the tetrapeptide of alanine and another four dipeptides. The overall RMS deviations in conformational energies and key dihedral angles for four di‐ or tetrapeptide, is 0.39 kcal/mol and 7.7°. The current results agree well with those by the accurate ab initio method, and are comparable to those from the best existing force fields. The results make us believe that our fluctuating charge model can obtain more promising results in protein and macromolecular modeling with good accuracy but less computer cost. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 1–10, 2006
Synthesis and characterization of novel aromatic poly(imide–benzoxazole) copolymers
Authors: Hsu Steve Lien‐Chung , Luo Guo‐Wei , Chen Hui‐Tzu , Chuang Shih‐Wei 
Published: October 2005

AbstractNew poly(imide–benzoxazole) copolymers were prepared directly from a dianhydride, a diacid chloride, and a bis(o‐diaminophenol) monomer in a two‐step method. In the first step, poly(amic acid–hydroxyamide) precursors were synthesized by low‐temperature solution polymerization in an organic solvent. Subsequently, the thermal cyclodehydration of the poly(amic acid–hydroxyamide) precursors at 350 °C produced the corresponding poly(imide–benzoxazole) copolymers. The inherent viscosities of the precursor polymers were around 0.19–0.33 dL/g. The cyclized poly(imide–benzoxazole) copolymers had glass‐transition temperatures in the range of 331–377 °C. The 5% weight loss temperatures ranged from 524 to 535 °C in nitrogen and from 500 to 514 °C in air. The poly(imide–benzoxazole) copolymers were amorphous, as evidenced by the wide‐angle X‐ray diffraction measurements. The structures of the precursor copolymers and the fully cyclized copolymers were characterized by Fourier transform infrared, 1H NMR, and elemental analysis. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6020–6027, 2005
An intuitive approach to measuring protein surface curvature
Authors: Coleman Ryan G. , Burr Michael A. , Souvaine Diane L. , Cheng Alan C. 
Published: October 2005

AbstractA natural way to measure protein surface curvature is to generate the least squares fitted (LSF) sphere to a surface patch and use the radius as the curvature measure. While the concept is simple, the sphere‐fitting problem is not trivial and known means of protein surface curvature measurement use alternative schemes that are arguably less straightforward to interpret. We have developed an approach to solve the LSF sphere problem by turning the sphere‐fitting problem into a solvable plane‐fitting problem using a transformation known as geometric inversion. The approach works on any arbitrary surface patch, and returns a radius of curvature that has direct physical interpretation. Additionally, it is flexible in its ability to find the curvature of an arbitrary surface patch, and the “resolution” can be adjusted to highlight atomic features or larger features such as peptide binding sites. We include examples of applying the method to visualization of peptide recognition pockets and protein conformational change, as well as a comparison with a commonly used solid‐angle curvature method showing that the LSF method produces more pronounced curvature results. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Rapid detection and characterization of minor reactive metabolites using stable‐isotope trapping in combination with tandem mass spectrometry
Authors: Yan Zhengyin , Maher Noureddine , Torres Rhoda , Caldwell Gary W. , Huebert Norman 
Published: October 2005

AbstractStable‐isotope trapping combined with mass spectrometry (MS) neutral loss scanning has recently been developed as a high‐throughput method for thein vitroscreening of major reactive metabolites. In fact, detection and identification of minor reactive metabolites are equally important since the minor metabolites, even though at low levels, may be highly reactive and also play an important role in drug‐induced adverse reactions. In this study, 2‐acetylthiophene, clozapine, troglitazone and 7‐methylindole were selected as model compounds to further validate the advantages of this method for rapid detection and structural characterization of minor glutathione (GSH) adducts derived from reactive metabolites. The utility of the current method was clearly demonstrated by successful identification of novel reactive metabolites at low levels and also minor ones either masked by non‐specific responses or co‐eluted with other conjugates. In comparison with existing methods, this method is sensitive, efficient, and suitable for rapid screening and more complete profiling of reactive metabolites. Copyright © 2005 John Wiley & Sons, Ltd.
The use of chemical derivatization to enhance liquid chromatography/tandem mass spectrometric determination of 1‐hydroxypyrene, a biomarker for polycyclic aromatic hydrocarbons in human urine
Authors: Li Yinghe , Li Austin C. , Shi Haihong , Zhou Shaolian , Shou Wilson Z. , Jiang Xiangyu , Naidong Weng , Lauterbach John H. 
Published: October 2005

AbstractThis article presents an analytical approach that used chemical derivatization to enhance mass spectrometric (MS) response in electrospray ionization (ESI) mode of 1‐hydroxypyrene (1‐OHP), a commonly used biomarker to monitor human exposure to polycyclic aromatic hydrocarbons (PAHs). The enhancement successfully enabled the desired detection of 50 pg/mL in human urine. The introduction of an MS‐friendly dansyl group to 1‐OHP enhanced both ionization efficiency in the ESI source and collision‐activated dissociation (CAD) in the collision cell. The response increase was estimated to be at least 200‐fold, and enabled the reduction of sample size to only 100 µL. The selective MS detection also facilitated a fast (run time 3 min) liquid chromatography (LC) method which successfully resolved the analyte and interferences. The sample processing procedure included enzymatic hydrolysis of glucuronide and sulfate conjugates, liquid‐liquid extraction, derivatization with dansyl chloride and a final liquid‐liquid extraction to generate clean extracts for LC/MS/MS analysis. This approach has been validated as sensitive, linear (50–1000 pg/mL), accurate and precise for the quantitation of 1‐OHP in human urine. This is the first report of using chemical derivatization to enhance MS/MS detection with fast chromatography in the determination of 1‐OHP in human urine. Copyright © 2005 John Wiley & Sons, Ltd.
Determination of protein phosphorylation sites by mass spectrometry: a novel electrospray‐based method
Authors: Alverdi Vera , Di Pancrazio Francesca , Lippe Giovanna , Pucillo Carlo , Casetta Bruno , Esposito Gennaro 
Published: October 2005

AbstractSeveral methods are used to identify protein phosphorylation sites. We report a novel electrospray‐based method for the determination of phosphorylation sites by mass spectrometry, using two different declustering potential values. This method allows one to obtain, with a single liquid chromatography/mass spectrometry (LC/MS) run, the pattern with either the phosphorylated or the unphosphorylated species of a protein tryptic digest, that can be further analyzed by tracing back the origin of each HPO3‐deprived form using the capabilities of tandem mass spectrometers. Copyright © 2005 John Wiley & Sons, Ltd.
Adolescents’ perception of risk and challenge: A qualitative study
Authors: Rodham Karen , Brewer Helen , Mistral Willm , Stallard Paul 
Published: October 2005

ABSTRACTConcern has been mounting about the increasing numbers of adolescents who engage in risky behaviours. This qualitative study aimed to identify adolescents’ perception of risk and explored the factors that adolescents felt influenced their decisions about engaging in risky behaviours. The results indicated that adolescents perceived risk to be something where the outcome was uncontrollable. In contrast, challenges were thought of as having a known end point that was difficult to achieve. They considered themselves to be well‐informed about health risks facing them, yet mentioned occasions when they lacked the ability to state that they did not want to engage in certain “risky” behaviours. The implications of the findings for future interventions are discussed.
Parental influences on young people's sexual behaviour: A longitudinal analysis
Authors: Wight Daniel , Williamson Lisa , Henderson Marion 
Published: October 2005

ABSTRACTBoth family structure and processes have been associated with young people's sexual behaviour, but most studies are cross‐sectional and focus on only one outcome: age at first intercourse. This paper uses longitudinal data from a survey of Scottish teenagers () to show how low parental monitoring predicts early sexual activity for both sexes (with some reverse causation), and for females it also predicts more sexual partners and less condom use. A lot of spending money also predicts early sexual activity and, for males, having more sexual partners. Comfort talking with parents about sex, however, seems to bear little relationship to sexual behaviour.
A statin in the treatment of heart failure? Controlled rosuvastatin multinational study in heart failure (CORONA): Study design and baseline characteristics
Authors: Kjekshus John , Dunselman Peter , Blideskog Malin , Eskilson Christina , Hjalmarson Åke , McMurray John V. , Waagstein Finn , Wedel Hans , Wessman Peter , Wikstrand John ,   on behalf of the CORONA Study Group
Published: October 2005

AbstractBackground:Previous prospective outcome studies of statins have not provided any guidance on benefit‐risk in patients with heart failure.Aim:The primary objective is to determine whether rosuvastatin (10 mg) reduces the combined endpoint of cardiovascular mortality, non‐fatal myocardial infarction or non‐fatal stroke (time to first event). The first secondary endpoint is all‐cause mortality.Methods:CORONA is a randomized, double‐blind, placebo‐controlled trial. Briefly, men and women, aged ≥60 years with chronic symptomatic systolic heart failure of ischemic aetiology and ejection fraction ≤0.40 (NYHA class III and IV) or ≤0.35 (NYHA class II) were eligible if they were not using or in need of cholesterol lowering drugs.Results:Mean age was 73 years (n=5016; 24% women), with 37% in NYHA II and 62% in NYHA III, ejection fraction 0.31, total cholesterol 5.2 mmol/L. Sixty percent have a history of myocardial infarction, 63% hypertension, and 30% diabetes. Patients are well treated for heart failure with 90% on loop or thiazide diuretics, 42% aldosterone antagonists, 91% ACE inhibitor or AT‐I blocker, 75% beta‐blockers, and 32% digitalis.Conclusion:CORONA is important for three main reasons: (1) A positive result is very important because of the high risk of the population studied, the increasing prevalence of elderly patients with chronic symptomatic systolic heart failure in our society, and the health economic issues involved. (2) If negative, new mechanistic questions about heart failure have to be raised. (3) If neutral we can avoid unnecessary polypharmacy.
Clinical trials update from the European Society of Cardiology meeting 2005: CARE‐HF extension study, ESSENTIAL, CIBIS‐III, S‐ICD, ISSUE‐2, STRIDE‐2, SOFA, IMAGINE, PREAMI, SIRIUS‐II and ACTIVE
Authors: Cleland John G.F. , Coletta Alison P. , Lammiman Mike , Witte Klaus K. , Loh Huan , Nasir Mansoor , Clark Andrew L. 
Published: October 2005

AbstractThis article provides information and a commentary on trials presented at the European Society of Cardiology meeting held in September 2005, relevant to the pathophysiology, prevention and treatment of heart failure. All reports should be considered as preliminary data, as analyses may change in the final publication. In the CARE‐HF extension study, the benefits of cardiac resynchronisation therapy (CRT) observed in the original study were maintained over an increased follow‐up period. A study of oral enoximone (25–50 mg t.i.d.) in advanced heart failure (ESSENTIAL) showed limited benefit compared to placebo. The CIBIS‐III study showed that heart failure therapy could be safely initiated with bisoprolol followed by the addition of enalapril. A subcutaneous ICD system (S‐ICD) showed potential as an alternative to a transvenous ICD. In the ISSUE‐2 study, an implantable loop recorder was used to guide therapy in patients with recurrent syncope. The selective endothelin antagonist sitaxsentan improved 6‐MWT and functional class in patients with pulmonary arterial hypertension in the STRIDE‐2 study. In SOFA, fish oil had no beneficial effect on the incidence of life‐threatening arrhythmias in patients with an ICD. In IMAGINE, quinapril showed no benefit when administered to patients following CABG. Perindopril reduced cardiac remodelling in post‐MI patients with normal LV function in PREAMI. SIRIUS‐II showed encouraging results for the use of intravenous ularitide in symptomatic decompensated chronic heart failure. The ACTIVE W study of warfarin versus aspirin plus clopidogrel in atrial fibrillation has been stopped due to superiority of warfarin.
An improved multiple-frequency method for measuring in situ target strengths
Authors: Conti Stéphane G. , Demer David A. , Soule Michael A. , Conti Jean H.E. 
Published: October 2005

Abstract
Refinements have been made to the multiple-frequency method for rejecting overlapping echoes when making target-strength measurements with split-beam echosounders described in Demer et al. (1999). The technique requires that echoes, simultaneously detected with two or more adjacent split-beam transducers of different frequencies, pass multiple-target rejection algorithms at each frequency, and characterize virtually identical three-dimensional target coordinates. To translate the coordinates into a common reference system for comparison, the previous method only considered relative transducer positions and assumed that the beam axes of the transducers were parallel. The method was improved by first, optimizing the accuracy and precision of the range and angular measurements of the individual frequency detections; and second, precisely determining acoustically the relative positions and angular orientations of the transducers, thus completely describing the reference-system transformation(s). Algorithms are presented for accurately and precisely estimating the transformation parameters, and efficiently rejecting multiple targets while retaining measurements of most single targets. These improvements are demonstrated through simulations, controlled test-tank experiments, and shipboard measurements using 38- and 120-kHz split-beam transducers. The results indicate that the improved multiple-frequency TS method can reject more than 97% of multiple targets, while allowing 99% of the resolvable single targets to be measured.
Does the largest chela of the males of three crab species undergo an allometric change that can be used to determine morphometric maturity?
Authors: Hall Norman G. , Smith Kim D. , de Lestang Simon , Potter Ian C. 
Published: October 2005

Abstract
The allometry of the largest chela of male crabs has often been assumed to undergo a change at the pubertal moult, i.e. the moult to maturity, and could therefore be used as a basis for determining the size of males at morphometric maturity. As initial plots of the logarithms of the length of the propodus of the chela and carapace width (CW) or length (CL) of male Portunus pelagicus, Hypothalassia acerba, and Chaceon bicolor revealed no conspicuous change in allometry, we used an information-theoretic approach and a range of models to explore, in greater depth, whether the chelae of these species did undergo such an allometric change. The candidate models were linear, quadratic, cubic, and broken-stick models, and broken-stick and two-line-segment models with logistic transitions between line segments. There was strong evidence that the largest chela of male P. pelagicus undergoes a subtle change in allometry at 82.0 cm CW, which is only 6.4 mm less than that at which 50% of males attain physiological maturity. Further, as the 95% confidence region of this estimate of size at morphometric maturity overlaps that for physiological maturity, the sizes at which morphometric and physiological maturity are attained by male P. pelagicus are similar. Because the estimate of the carapace length at which allometric change in the chela of male H. acerba was very imprecise, there was far less convincing evidence that the allometry of the chela of this species undergoes a conspicuous change at a certain length. The allometry of the chelae of male C. bicolor changed progressively and continuously with body size, and did not change abruptly at a particular size. In view of the morphometric results for H. acerba and C. bicolor, it would be advisable to base management plans for conservation on the carapace lengths at which 50% of the male crabs of these two species attain physiological maturity, i.e. 68.1 and 94.3 mm, respectively.
A sector‐wide approach to emergency obstetric care in Uganda
Authors: Orinda V. , Kakande H. , Kabarangira J. , Nanda G. , Mbonye A.K. 
Published: October 2005

AbstractPurposeTo establish a baseline for the availability, utilization, and quality of EmOC, and to help develop an operational strategy based on the findings.MethodsA needs assessment of emergency obstetric care (EmOC) was carried out in 197 health facilities in 19 out of 56 districts in Uganda, covering 38% of the total population.FindingsThere were a large number of missing signal functions at health facilities and an urgent need to improve the availability of EmOC.ConclusionBy using the data from the assessment, it was possible to influence national policy through the health sector‐wide approach (SWAp) and place EmOC high on the national agenda. A national strategy and roll out plan to strengthen EmOC is now in place.
Delivery of the second twin
Authors: Ginsberg N.A. , Levine E.M. 
Published: October 2005

AbstractObjectiveTo determine the likelihood of cesarean for the second twin after vaginal delivery of the first and the risk of vaginal delivery.MethodA retrospective analysis of twin deliveries was performed on 10,365 live born twin pairs (20,730 births), using birth certificate data from the State of Illinois from 1997 through 2000.ResultThe incidence of cesarean for the second twin after vaginal delivery of the first was 10.1%. The greatest incidence of failed vaginal delivery of the second twin was in the vertex/non‐vertex group. Five‐minute Apgar scores < 4 were significantly more frequent in vaginally delivered twins < 2000 g compared to those delivered via cesarean (p < 0.001).ConclusionTwin presentation type is predictive of the likelihood of a failed vaginal delivery of the second twin. Cesarean appears to significantly reduce the incidence of Apgars < 4 for neonates < 2000 g.
Loss of Reflex Tearing: An Expected Consequence of Juvenile Nasopharyngeal Angiofibroma
Authors: Hillel Alexander T. , Metzinger Rebecca C. , Nemechek Andrew J. , Nuss Daniel W. 
Published: October 2005

OBJECTIVE:To report the loss of reflex tearing after surgical treatment of juvenile nasopharyngeal angiofibroma (JNA).STUDY DESIGN AND SETTING:A retrospective case series of 8 patients with surgical extirpation of JNA from 1995 to 2003 in a major teaching hospital setting was studied for symptomatic xerophthalmia.RESULTS:One patient was lost to follow‐up. Four of the remaining 7 patients reported a dry ipsilateral eye after surgical treatment of JNA.CONCLUSION:The location of the pterygopalatine ganglion and its associated fibers in the pterygopalatine fossa is directly adjacent to the location of origin of JNA. Lacrimal innervation passes through the pterygopalatine ganglion. Given the extensive nature of advanced JNA and mandate for complete surgical excision, lacrimal dysfunction should be considered an expected consequence of surgery.SIGNIFICANCE:The loss of reflex tearing has not been reported as a consequence of JNA or its surgical treatment. EBM Rating: C.
Radiation Dose to the Eyes and Parotids during CT of the Sinuses
Authors: Bassim Marc K. , Ebert Charles S. , Sit Roger C. , Senior Brent A. 
Published: October 2005

OBJECTIVE:To measure the radiation dose to the lens and parotid during high‐resolution computed tomography scan of the sinuses.STUDY DESIGN AND SETTING:Nine cadaver heads were scanned in the axial plane by means of a fine‐cut (0.75 mm) protocol. Images were then reconstructed in the coronal and sagittal planes for use with the image guidance software. Thermoluminescent dosimeters were taped over the eyes and parotids and used to measure the radiation dose absorbed by these organs.RESULTS:Doses obtained were 29.5 mGy for the lens and around 30 mGy for the parotid.CONCLUSION:The measured doses are lower than the reported acute thresholds of 500‐2000 mGy for lens opacities and well below the threshold of 2500 mGy for damage to the parotid.SIGNIFICANCE:These results demonstrate minimal risk from radiation through the use of high‐resolution computed tomography and support the use of such a protocol for diagnosis and preoperative planning.
Surgical Anatomy of the Recurrent Laryngeal Nerve Revisited
Authors: Shindo Maisie L. , Wu James C. , Park Eunice E. 
Published: October 2005

OBJECTIVES:Previous anatomic studies of the recurrent laryngeal nerves (RLNs) have described the variability in the course of the RLN. The anatomy of the nerve appears more constant along its distal segment near the cricothyroid joint, which is our surgical approach to the initial identification of the nerve. Understanding the topographical anatomy of the nerve in this region facilitates quick and safe nerve identification. The surgical topographical anatomy of the nerve in this region has not been studied in detail, which is the focus of this study.METHODS:A total of 278 RLNs in 190 patients were dissected during thyroidectomy and/or parathyroidectomy. The course of the nerve was recorded, paying particular attention to the directional course along its distal portion. The angle in which it coursed in relationship to a line paralleling the tracheoesophageal groove was determined.RESULTS:All 278 nerves were identified. Seventy‐eight percent of the right‐sided nerves coursed between 15 and 45 degrees, and 77% of the left‐sided nerves coursed between 0 and 30 degrees. It appears that the nerve is more likely to travel at a more obtuse angle with right‐sided RLNs and in patients with a low‐lying cricoid. There was no permanent postoperative RLN palsy, and the incidence of temporary palsy was 1%.CONCLUSIONS:Approaching the nerve along its distal portion is safe and effective. The surgical topographical anatomy in this region is described in detail. Some of the potential advantages of identifying the nerve more distally include less chance of disrupting the blood supply to the inferior parathyroid gland, dissection along a shorter portion of the nerve, and less variability of the nerve.