bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation, characterization and cytocompatibility of porous ACP/PLLA composites
Authors: Gao Yanbo , Weng Wenjian , Cheng Kui , Du Piyi , Shen Ge , Han Gaorong , Guan Binggang , Yan Weiqi 
Published: July 2006

AbstractThe purpose of this work was to incorporate amorphous calcium phosphate (ACP) into porous poly(L‐lactic acid) (PLLA), because ACP is capable of fast phase transformation and morphological change in body fluid, such, a desired pore wall surface within bone tissue engineering scaffolds can be created. A highly porous ACP/PLLA composite was prepared by a thermally induced phase separation technique. The results showed that the composite had an interconnected pore structure with 100 μm macropores and 10 μm micropores, and 91% porosity; 40 nm primary particles of ACP were agglomerated to 3 μm aggregates, and the aggregates were homogeneously distributed in pore walls; These aggregates showed to be in situ transformed into bone‐like apatite after 1 h soaking in phosphate buffered saline solution. Human osteoblast‐like cell culture showed that the ACP/PLLA composite had better cell adhesion and alkaline phosphotase activity than pure PLLA. This study demonstrates that the ACP/PLLA composite can enhance cytocompatibility and could act as a promising scaffold for bone tissue engineering. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Nanoimaging for protein misfolding and related diseases
Authors: Lyubchenko Yuri L. , Sherman Simon , Shlyakhtenko Luda S. , Uversky Vladimir N. 
Published: July 2006

AbstractMisfolding and aggregation of proteins is a common thread linking a number of important human health problems. The misfolded and aggregated proteins are inducers of cellular stress and activators of immunity in neurodegenerative diseases. They might posses clear cytotoxic properties, being responsible for the dysfunction and loss of cells in the affected organs. Despite the crucial importance of protein misfolding and abnormal interactions, very little is currently known about the molecular mechanism underlying these processes. Factors that lead to protein misfolding and aggregation in vitro are poorly understood, not to mention the complexities involved in the formation of protein nanoparticles with different morphologies (e.g., the nanopores) in vivo. A better understanding of the molecular mechanisms of misfolding and aggregation might facilitate development of the rational approaches to prevent pathologies mediated by protein misfolding. The conventional tools currently available to researchers can only provide an averaged picture of a living system, whereas much of the subtle or short‐lived information is lost. We believe that the existing and emerging nanotools might help solving these problems by opening the entirely novel pathways for the development of early diagnostic and therapeutic approaches. This article summarizes recent advances of the nanoscience in detection and characterization of misfolded protein conformations. Based on these findings, we outline our view on the nanoscience development towards identification intracellular nanomachines and/or multicomponent complexes critically involved in protein misfolding. J. Cell. Biochem. © 2006 Wiley‐Liss, Inc.
A Kirkwood‐Buff derived force field for amides
Authors: Kang Myungshim , Smith Paul E. 
Published: July 2006

AbstractA force field for the computer simulation of aqueous solutions of amides is presented. The force field is designed to reproduce the experimentally observed density and Kirkwood–Buff integrals for N‐methylacetamide (NMA), allowing for an accurate description of the NMA activity. Other properties such as the translational diffusion constant and heat of mixing are also well reproduced. The force field is then extended to include N,N′‐dimethylacetamide and acetamide with good success. Analysis of the simulations of low concentrations of NMA in water indicates a high degree of solvation with only 15% of the NMA molecules involved in solute–solute hydrogen bonding. There is only a weak angular dependence of the solute–solute hydrogen bonding interaction with a minimum at an angle of 65° for the NH and CO dipole vectors. The models presented here provide a basis for an accurate force field for peptides and proteins. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 1477–1485, 2006
Bone‐specific heparan sulfates induce osteoblast growth arrest and downregulation of retinoblastoma protein
Authors: Manton Kerry J. , Sadasivam Murali , Cool Simon M. , Nurcombe Victor 
Published: July 2006

AbstractThe heparan sulfate (HSs) sugars of the extracellular matrix (ECM) play a key role during both development and wound repair in regulating the flow of growth and adhesive factors across their cell surface receptors. The aim of this study was to assess the structural and functional differences of HS chains extracted from the conditioned media (soluble), cell surface, and ECM of primary human osteoblast cultures, and to analyze their effects on osteoblast cell growth. HS chains from these compartments were characterized through a combination of enzymatic degradation, anion exchange chromatography, and molecular sieving. Although the chains were all approximately the same size, they varied systematically in their sulfate content, suggesting differences in their protein‐binding domains. When added to pre‐confluent hFOB1.19 osteoblast cultures, HS doses exceeding 500 ng/ml inhibited proliferation, without affecting viability, irrespective of their origin. Furthermore, HS doses of 500 ng/ml also downregulated retinoblastoma, Cyclin A and CDK1 protein expression, indicating that high doses of osteoblast HS negatively regulate cell cycle, resulting in growth arrest; when high doses of HS were withdrawn after a prolonged period, linear cell growth was reestablished. Thus, despite differences in sulfation, HS from either the soluble, cell surface, or matrix compartments of primary human osteoblast cultures are functionally similar with respect to their effects on growth. Binding assays revealed that the HS chains bound TGFβ1, a known inhibitor of osteoprogenitor growth, at higher affinity than a suite of other bone‐related, heparin‐binding growth factors. Overcoming such sugar‐mediated inhibition may prove important for wound repair. J. Cell. Physiol. 209: 219–229, 2006. © 2006 Wiley‐Liss, Inc.
Asylum‐seekers and refugees: a structuration theory analysis of their experiences in the UK
Authors: Healey Ruth L. 
Published: July 2006

AbstractMuch of the literature on asylum‐seekers and refugees tends to be atheoretical. This article uses ideas from Giddens' structuration theory as a conceptual framework to analyse the voices of a group of asylum‐seekers and refugees. The empirical database consists of semi‐structured interviews with 18 asylum‐seekers and refugees living in the UK from a wide range of countries, including Ethiopia, Kenya, Poland, Somalia and the Yemen. The study shows that the experiences of asylum‐seekers and refugees are impacted by both structural and individual agency factors. The former, it is argued, consist of public and political reaction towards the increase in the number of asylum applications, while the latter include asylum‐seeker and refugee experiences of specific places and people which can create social networks. Structural factors had the greatest impact upon the integration of the participants into the host society. The nature of the experiences of asylum‐seekers and refugees can influence the way they feel about their position in the host society. For example, negative experiences of the UK can reduce their sense of security in the society, whereas positive experiences can increase their feelings of comfort. Structuration theory conceptualises how asylum‐seekers and refugees utilise coping strategies to raise their comfort level in the host country. Copyright © 2006 John Wiley & Sons, Ltd.
Theory of spintronic materials
Authors: Chelikowsky James R. , Kaxiras Efthimios , Wentzcovitch Renata M. 
Published: July 2006

AbstractThe ability to manipulate and understand spin polarized materials is a key to constructing spintronic devices, i.e., devices in which the electron'sspinand charge are both utilized. Here we review computational methods for predicting the properties of spin‐polarized materials at the macro‐ and nano‐limits, and at interfaces. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The hazards to practitioners of obstetric and gynecological ultrasound
Authors: Hackmon R. , Sheiner E. , Barnhard Y. , Beer R. , Meizner I. 
Published: July 2006

AbstractObjectivesTo investigate the specific complaints of physicians and technicians performing obstetric and gynecological ultrasound.MethodsThis was a cross‐sectional retrospective survey. Questionnaires were distributed to members of the Israeli Society of Gynecological Ultrasound, including questions on gender and profession, number and type of scans performed, pain related to profession and any therapy undergone. Statistical analysis included chi‐square or Fisher's exact test, Student's t‐test, Pearson's correlation coefficient and logistic regression.ResultsJoint pain was reported by 51.7% (30/58) of the technicians compared with 25.3% (19/75) of the physicians (P = 0.002). It was more common in females than in males (P = 0.05) and it was more common among those who performed transabdominal sonography more frequently than they did transvaginal sonography (P = 0.004). There was a significant association between performing transabdominal ultrasound and back pain (P = 0.05). Although females reported pain more frequently, the rate of surgical procedures was higher among males (P < 0.05).ConclusionsA technician is 3.5 times more likely to report joint pain than is a physician. Transabdominal sonography is a risk for both joint and back pain. There may be gender differences in pain perception. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Ductus venosus blood flow alterations in fetuses with obstructive lesions of the right heart
Authors: Berg C. , Kremer C. , Geipel A. , Kohl T. , Germer U. , Gembruch U. 
Published: July 2006

AbstractObjectiveTo assess the impact of isolated lesions of the fetal right heart on ductus venosus (DV) blood flow profiles.MethodsRetrospective evaluation of DV blood flow profiles in 83 fetuses with isolated right‐sided cardiac lesions. Cases were divided into two groups. Group A had right‐sided cardiac lesions associated with a large ventricular septal defect that equalized interventricular pressures (double outlet right ventricle (n = 12), tetralogy of Fallot (n = 19), pulmonary atresia (n = 5)). Group B had right‐sided cardiac lesions with obstruction of the inflow (tricuspid atresia with ventricular septal defect (n = 14)) or obstruction of the outflow with intact ventricular septum (Ebstein's anomaly (n = 13), pulmonary stenosis (n = 13) and pulmonary atresia (n = 7)). Comparisons were made with 585 uneventful singleton pregnancies and previously published normative values.ResultsFetuses in Group B had significantly higher rates of abnormal DV flow profiles compared to Group A and controls (P < 0.01). Conversely, there were no significant differences concerning DV parameters between fetuses in Group A and controls. Despite these different DV flow characteristics, there were no significant differences concerning signs of cardiac failure and/or survival to the perinatal period between the two groups.ConclusionsRight‐sided cardiac lesions with obstruction of the inflow or outflow with intact ventricular septum are significantly associated with abnormally high pulsatilities in the DV and may even cause a reversal of flow during atrial contraction. These changes do not necessarily indicate cardiac failure, as they are primarily attributable to the special hemodynamics of the cardiac defect. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Probe-level measurement error improves accuracy in detecting differential gene expression
Authors: Liu Xuejun , Milo Marta , Lawrence Neil D , Rattray Magnus 
Published: July 2006

AbstractMotivation: Finding differentially expressed genes is a fundamental objective of a microarray experiment. Numerous methods have been proposed to perform this task. Existing methods are based on point estimates of gene expression level obtained from each microarray experiment. This approach discards potentially useful information about measurement error that can be obtained from an appropriate probe-level analysis. Probabilistic probe-level models can be used to measure gene expression and also provide a level of uncertainty in this measurement. This probe-level measurement error provides useful information which can help in the identification of differentially expressed genes.Results: We propose a Bayesian method to include probe-level measurement error into the detection of differentially expressed genes from replicated experiments. A variational approximation is used for efficient parameter estimation. We compare this approximation with MAP and MCMC parameter estimation in terms of computational efficiency and accuracy. The method is used to calculate the probability of positive log-ratio (PPLR) of expression levels between conditions. Using the measurements from a recently developed Affymetrix probe-level model, multi-mgMOS, we test PPLR on a spike-in dataset and a mouse time-course dataset. Results show that the inclusion of probe-level measurement error improves accuracy in detecting differential gene expression.Availability: The MAP approximation and variational inference described in this paper have been implemented in an R package pplr. The MCMC method is implemented in Matlab. Both software are available fromContact: magnus.rattray@manchester.ac.ukSupplementary Information: Supplementary data are available at Bioinformatics Online.
Topical Intranasal Fluorescein: The Missing Partner in Algorithms of Cerebrospinal Fluid Fistula Detection
Authors: Saafan Magdy E. , Ragab Sameh M. , Albirmawy Osama A. 
Published: July 2006

AbstractObjective: The aim of this work was to focus on the development and validation of the use of topical fluorescein in the intraoperative localization of cerebrospinal fluid (CSF) fistulas, and to screen its use in preoperative diagnosis of CSF rhinorrhea as well as postoperative detection of a recurrence.Materials and Methods: Twenty‐five patients with CSF rhinorrhea were treated with an endoscopic endonasal technique. Topical intranasal 5% fluorescein was used for preoperative diagnosis and intraoperative localization of the site of the leak. A change in the color of the fluorescein from yellow to green fluorescence and sometimes streaming the fluorescein over the nasal mucosa and blood denoted the presence of CSF, and the site of the leak could be traced.Results: The cause of the leak was accidental trauma in 11 patients, spontaneous in 9 patients, and iatrogenic in 5 patients. The ethmoidal roof was the most common site of leak (52%) followed by the cribriform plate (40%) and then the sphenoid sinus (8%). We have achieved 100% success rate in sealing the CSF fistulas in our 25 patients with no recurrence detected during the follow‐up period (mean, 19 ± 10 months). The preoperative use of fluorescein‐soaked cotton pledgets was 100% accurate in diagnosing CSF rhinorrhea when compared with B2 transferrin testing. The intraoperative use of topical intranasal fluorescein was also 100% accurate in locating the site of the CSF fistula when compared with the surgical findings. No major complications have been reported.Conclusion: In the presence of a clinically diagnosed CSF leakage, topical fluorescein is a very easy, sensitive, safe, and highly accurate tool in the intraoperative localization of the site and extent of CSF fistulas, and should be considered a viable noninvasive alternative to intrathecal fluorescein. We also recommend its use as a simple and quick outpatient clinic test for preoperative diagnosis of CSF rhinorrhea. It can be used postoperatively as well when there is a doubt of recurrence of the CSF leak.
Endoscopic Assessment of the Dacryocystorhinostomy Ostium After Endoscopic Surgery
Authors: Mann Balwinder Singh , Wormald Peter John 
Published: July 2006

AbstractObjectives: Dacryocystorhinostomy (DCR) is currently regarded as the treatment of choice for treatment of epiphora resulting from blockage at the level of the nasolacrimal duct. There has been debate on the effect of healing on the size of the DCR ostium after surgery. The aim of this study is to determine how the size of the surgically created lacrimal ostium changes over time.Study Design: The authors conducted a prospective cohort study of unselected patients who underwent DCR from March 1999 to November 2004.Methods: Thirty‐eight patients who underwent intranasal DCR were analyzed. There were 14 males and 24 females with 11 patients undergoing bilateral DCR, resulting in 49 endoscopic intranasal DCRs being analyzed. The endoscopic findings of the size of the ostia were recorded at the time of surgery and at 4 weeks, 6 months, and 12 months after surgery. There were 33 DCRs reviewed at 12 months and 16 reviewed at 6 months who did not reattend for their 12‐month appointment. Analysis of variance was used to compare the difference in the ostium sizes at the end of surgery and at 4 weeks, 6 months, and 12 months after surgery.Results: The male to female ratio was 1:1.7 and the average age was 64.5 (standard deviation [SD] = 17.8 years). The ostium measured 11.8 (STD = 2.3, 95% confidence interval [CI] = 11.1–12.5) × 7.2 (SD = 1.7; 95% CI = 6.7–7.7) at the time of surgery and 10.1 (SD = 2.3; 95% CI = 9.3–10.9) × 6.4 (SD = 1.3; 95% CI = 6.0–6.9) at 4 weeks, 9.8 (SD = 2.5; 95% CI = 9.0–10.6) × 6.5 (SD = 1.5; 95% CI = 6.0–6.9) at 6 months, and 10.1 (SD = 2.5; 95% CI = 9.2–11.0) × 6.6 (SD = 1.6; 95% CI = 6.0–7.1) at 12 months. Statistical analysis (analysis of variance) showed a significant shrinkage from surgery to 4 weeks but no statistical difference from 4 weeks to 6 or 12 months.Conclusion: The DCR ostium shrinks a small but significant amount in the first 4 weeks after surgery. Thereafter, the ostium size appears to be stable. We propose that the surgical technique used in which the nasal and lacrimal mucosa is approximated results in a first intention healing with minimal ostial granulation tissue and stenosis and minimal shrinkage of the postoperative DCR ostium.
Bacterial Biofilms on the Sinus Mucosa of Human Subjects With Chronic Rhinosinusitis
Authors: Sanderson Alicia R. , Leid Jeff G. , Hunsaker Darrell 
Published: July 2006

AbstractIntroduction: Chronic rhinosinusitis (CRS) is a common disease poorly controlled by antibiotics. Postulated etiologies of CRS include allergy, fungi, functional factors, and biofilm.Objectives: We presented a preliminary study demonstrating bacterial biofilms' presence on the sinus mucosa of patients with CRS using fluorescent in situ hybridization (FISH). The advantage of FISH in biofilm identification is that it is the only method that identifies the specific bacteria creating the biofilm matrix. We now present the results of a larger series of patients.Methods: Patients with CRS scheduled for sinus surgery were enrolled in the study. Biopsies of the sinus mucosa and cultures were taken at the time of surgery. Control samples were taken from patients undergoing septoplasty. Specimens underwent FISH testing for Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenza, and Pseudomonas aeruginosa.Results: Bacterial biofilms were present on 14 of 18 specimens. The predominant species were H. influenzae, S. pneumoniae, and S. aureus. P. aeruginosa biofilm was not identified on any specimens. The intraoperative cultures of the planktonic bacteria present in the sinuses did not correlate with the biofilms identified. Two of the five control samples were positive for biofilm.Conclusion: The presence of biofilms on the mucosa of patients with CRS offers a possible cause of antimicrobial therapy failure and could change the approach to treatment. However, the presence of biofilms on healthy control samples implies that biofilms may simply be colonizers. The precise role that biofilms play in CRS still remains to be determined. Further studies with larger sample sizes are needed.
Cochlear Implants in Waardenburg Syndrome
Authors: Cullen Robert D. , Zdanski Carlton , Roush Patricia , Brown Carolyn , Teagle Holly , Pillsbury Harold C. , Buchman Craig 
Published: July 2006

AbstractObjective: Waardenburg syndrome is an autosomal‐dominant syndrome characterized by dystopia canthorum, hyperplasia of the eyebrows, heterochromia irides, a white forelock, and sensorineural hearing loss in 20% to 55% of patients. This patient population accounts for approximately 2% of congenitally deaf children. The purpose of this retrospective case review was to describe the outcomes for those children with Waardenburg syndrome who have undergone cochlear implantation.Methods: Pediatric cochlear implant recipients with documented evidence of Waardenburg syndrome underwent retrospective case review. All patients received their cochlear implants at the study institution followed by outpatient auditory habilitation. Charts were reviewed for etiology and duration of deafness, age at time of cochlear implantation, perioperative complications, duration of use, and performance outcomes. Results of standard tests batteries for speech perception and production administered as a part of the patients' auditory habilitation were reviewed.Results: Seven patients with Waardenburg syndrome and cochlear implants were identified. The average age at implantation was 37 months (range, 18–64 months) and the average duration of use was 69 months (range, 12–143 months). All of these patients are active users of their devices and perform very well after implantation. There were no major complications in this small group of patients.Conclusions: Children with congenital sensorineural hearing loss without other comorbidities (e.g., developmental delay, inner ear malformations) perform well when they receive cochlear implantation and auditory habilitation. Patients with Waardenburg syndrome can be expected to have above‐average performance after cochlear implantation.
Endoscopic Anterior Ethmoidal Artery Ligation: A Cadaver Study
Authors: Floreani Stephen R. , Nair Salil B. , Switajewski Michael C. , Wormald Peter‐John 
Published: July 2006

AbstractObjective: The objective of this study was to investigate the radiologic and endoscopic anatomy of the anterior ethmoidal canal (AEC) and feasibility of endoscopic ligation of the anterior ethmoidal artery (AEA).Study Design: The authors conducted a prospective analysis of computed tomography (CT) of the paranasal sinuses and endoscopic cadaver dissection.Methods: Twenty‐two cadaver heads had CT scans of the paranasal sinuses. The height of the lateral lamella of the cribriform plate was calculated and staged according to the Keros staging system. The presence of a bony mesentery, distance from AEC to the skull base, and dehiscence of the AEC were documented. Forty‐four dissections were performed, the AECs identified, and AEA ligation attempted.Results: The mean height of the lateral lamella was 5.4 mm on the right and 4.7 mm on the left. In all cadaver heads with asymmetry, the right lateral lamella was longer (P < .005). A Keros type 1 pattern was seen in 23%, type 2 in 50%, and type 3 in 27%. Thirty‐six percent of AECs were in a bony mesentery. AEC distance from the skull base was greater on the right (P < .009). A longer lateral lamella was correlated with the artery being in a mesentery. Sixteen percent of the AECs were dehiscent. Sixty‐six percent of AEAs were unable to be clipped. Twenty percent were clipped effectively, all in a mesentery. In 14%, the AEA was not effectively clipped.Conclusions: Endoscopic AEA ligation may be possible in some patients. The AEA should be in a mesentery for an effective clip to be placed and be associated with a dehiscence of the AEC. If the lateral lamella is classified as Keros grade 2 or 3, it is likely the AEC will be found in a mesentery.