bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical biochemistry guidelines in Wales: their impact on laboratory services
Authors: Griffiths K D , Duffy E J , Oleesky D A 
Published: February 2008

Background Evidence of significant variations in clinical biochemistry practice in Wales led to the formation of the All Wales Clinical Biochemistry Audit Group (AWCBAG) in 1993, with the aim of auditing laboratory services to ensure that they are optimally used. As part of this process, clinical guidelines are produced and circulated to all clinical biochemistry departments in Wales. The current aim of the AWCBAG is to assess the extent and impact of adoption of these guidelines across Wales. Methods Three surveys were despatched at intervals over a decade to all clinical biochemistry departments in Wales to investigate practice in: (1) urine albumin testing to screen for diabetic nephropathy; (2) biochemical investigation of menopausal status and the monitoring of hormone replacement therapy; (3) screening for Cushing's syndrome. Results The results show that laboratories across Wales are generally following guideline criteria and are adapting their practice in-line with changing recommendations. Conclusion The introduction of AWCBAG guidelines has been widely accepted by clinical biochemistry departments in Wales. These guidelines have led to a more efficient and effective use of laboratory services.
Supraphysiological doses of intravenous PYY3-36 cause nausea, but no additional reduction in food intake
Authors: le Roux Carel W , Borg Cynthia M , Murphy Kevin G , Vincent Royce P , Ghatei Mohammad A , Bloom Stephen R 
Published: February 2008

Background Peptide YY (PYY3-36) infused to levels within the physiological range reduces appetite and food intake in humans without nausea. However, PYY3-36 has previously been shown to cause nausea at higher doses. Methods We studied the relationship of PYY3-36, nausea and food intake in six volunteers, using three different PYY3-36 preparations infused to achieve supraphysiological PYY plasma levels. Results Supraphysiological levels of PYY caused nausea in five subjects ( P < 0.05). Although PYY3-36 increased satiety ( P < 0.05) and reduced food intake ( P < 0.05), no greater enhancement of satiety or inhibition of food intake was observed compared with previous reports. Conclusions This study cautions against the use of supraphysiological doses of PYY3-36 as it may increase nausea with no benefit in food reduction.
Extent of bilirubin interference with Beckman creatinine methods
Authors: Dimeski Goce , McWhinney Brett , Jones Brock , Mason Rebecca , Carter Andrew 
Published: February 2008

Background The aim of the study was to determine the extent of bilirubin interference on two different Beckman–Coulter creatinine methods used on the CX5 PRO/DxC 600 and the DxC 800 systems, respectively. Methods The Beckman methods were compared with a high-performance liquid chromatography (HPLC) method using 104 patient samples with creatinine concentrations <133 μmol/L and bilirubin concentrations of between 30 and 802 μmol/L. Results The linear regression analysis calculations expressing the relationship between bilirubin concentration and the observed difference between the Beckman and HPLC creatinine methods are: DxC800 creatinine M (modular or cup) method: r2 0.217, slope −0.023 and intercept 6.43; and DxC600 method: r2 0.7324, slope −0.0882 and intercept 12.01. Conclusions There is significantly greater interference by bilirubin on the CX5 PRO/DxC 600 method, which can lead to inaccuracy in the calculation of the estimated glomerular filtration rate by the Modification of Diet in Renal Disease equation.
Diagnosing unsuspected hypopituitarism in adults from suggestive thyroid function test results
Authors: Preiss David , Todd Louise , Panarelli Maurizio 
Published: February 2008

Background The typical pattern of thyroid function tests (TFTs) associated with hypopituitarism consists of subnormal free T4 (fT4) or total T4 and normal or marginally elevated thyroid-stimulating hormone (TSH). A previous study calculated an incidence of hypopituitarism of 3.2 cases/100,000/year by following up abnormal TFTs. The aim of this study was to verify the incidence of unsuspected hypopituitarism diagnosed by reflective testing on such samples in a Scottish population. Methods Prospective audit of TFT results over 15 months. Individuals with suitable results (fT4 < 9 pmol/L, TSH < 10 mU/L) were identified by the laboratory information system at the Biochemistry Department, Glasgow Royal Infirmary, serving a population of 200,000. fT4 (repeat analysis following assay recalibration), total T3, testosterone (males), luteinizing hormone, follicle-stimulating hormone, prolactin and cortisol were analysed on appropriate samples. Results Three hundred and eleven suitable results from 266 adult individuals were identified from a total of 73,650 TFT results, leading to the diagnosis of 10 new cases (age range 28–90 years) of hypopituitarism (approximately 4 cases/100,000/year). Nine patients now attend endocrine clinics. Pituitary imaging was abnormal in five cases (2 large pituitary tumours, one macroadenoma, 2 empty sellae), normal in three cases and two patients were not scanned. Conclusions A significant number of cases of unsuspected hypopituitarism can be diagnosed by reflective testing on appropriate samples. fT4 should be an integral part of frontline TFTs as TSH alone cannot assist in the identification of possible hypopituitarism. Laboratories are in an excellent position to assist in early identification of hypopituitarism, which may lead to improved outcomes in such patients.
Delay in separating blood samples affects creatinine measurement using the Roche kinetic Jaffe method
Authors: Ford Loretta , Berg Jonathan 
Published: February 2008

Background We have examined the effect of delayed sample separation on serum creatinine measurement using the kinetic Jaffe method and estimated glomerular filtration rate (eGFR), and the impact this can have on chronic kidney disease (CKD) staging. Methods In a preliminary study clotted samples were left at room temperature for up to 48 h prior to centrifugation and serum creatinine measurement on a Roche modular analyser. A larger study then used paired clotted samples separated at baseline (30 min) and after 24 h at room temperature. To determine the effect on CKD staging, eGFR was calculated using the simplified [4-v] Modification of Diet in Renal Disease formula. Results Preliminary study. A significant increase in creatinine concentration ( P < 0.001) occurred after a 16 h delay in sample separation. By 48 h the mean increase in creatinine was 29% (range 21–63%). Twenty-four hour delay study. The mean increase in creatinine for 113 outpatient samples after delaying sample separation by 24 h was 11%, and exhibited considerable individual variation (range 2–87%). CKD staging for 32% of the group changed, 26% from stage 1 to 2 and 6% from stage 2 to 3. Conclusions Delay in sample separation affects the creatinine measurement using the Roche kinetic Jaffe reaction, and can result in the misclassification of CKD staging. Laboratories using the kinetic Jaffe method should not report creatinine results where there has been a delay in separation. This advice should also be reflected in practice guidelines.
Learning needs in clinical biochemistry for doctors in foundation years
Authors: Khromova Victoria , Gray Trevor A 
Published: February 2008

Background Most medical school curricula have reduced the amount of time available for teaching in pathology despite the fact that junior staff in the early stages of their training were responsible for requesting the majority of pathology tests on acutely ill hospital patients. So, the lack of specific training in this area means that test requesting may be poorly performed and the results ill understood by these staff. This paper describes a questionnaire, which was designed to assist laboratory staff providing targeted teaching in this area. Methods Doctors in Foundation year 1 (F1) and Foundation year 2 (F2) in Sheffield teaching hospitals were given a questionnaire to ascertain how confident they were in requesting and interpreting the results of clinical biochemistry tests. The doctors were also asked about which areas of laboratory medicine they would like to be taught. Results Responses were received from 82 doctors, about half those in F1 and F2. The survey revealed areas where juniors are less confident in requesting tests and interpreting results. Despite lack of confidence in interpreting the result, 18% were confident about requesting tests. Doctors were also unsure of the effects of common problems like haemolysis on the interpretation of results. More than 70% of the doctors requested specific teaching in these areas. Conclusions Foundation doctors have learning needs in clinical biochemistry, addressing which would assist them in patient care. While better training in medical school may help in future, there are specific needs for those on the wards now that require targeted teaching.
Are biochemistry interpretative comments helpful? Results of a general practitioner and nurse practitioner survey
Authors: Barlow Ian M 
Published: February 2008

Background Adding or incorporating clinical interpretative comments on biochemistry results is widespread in UK laboratories; although this consumes considerable human resource, there is still little evidence to suggest that it is either effective or appreciated by our clinical colleagues. I therefore decided to survey our local general practitioners (GPs) and nurse practitioners to analyse whether they found biochemistry comments on reports helpful. Methods A simple questionnaire was designed and sent to 159 GPs and 81 nurse practitioners asking them whether they found this activity useful for the limited range of test groups that we routinely comment on and also whether they would like to see commenting on more groups of tests. Results Overall, 49.6% of questionnaires were returned. Of these, there was overwhelming support for commenting on reports and 77% would like to see comments on a greater range of tests. Conclusions Although adding clinical interpretative comments is very time-consuming for senior laboratory staff, there is overwhelming support of this activity among our GPs and nurse practitioner users; therefore, our local policy of routinely adding clinical comments will remain for the foreseeable future.
Association of leprosy with HLA-DRB1 in an Argentinean population
Authors: Borrás Silvia García , Cotorruelo Carlos , Racca Liliana , Recarte Mónica , Garcías Celeste , Biondi Claudia , Bottasso Oscar , Racca Amelia 
Published: February 2008

Background Previous studies have suggested an influence of HLA molecules on the regulation of the anti Mycobacterium leprae immune response. Methods DNA typing of HLA-DRB1 alleles in 71 leprosy patients and 81 healthy controls was performed. Genomic DNA was extracted from peripheral blood and used as a template to amplify the polymorphic second exon of the HLA-DRBl by the ploymerase chain reaction (PCR). PCR products were hybridized separately with sequence-specific oligonucleotides. Results DRB1*1401 and DRB1*1406 alleles were significantly more prevalent in leprosy patients, whereas a decreased frequency of DRB1*0808 and DRB1*1103 alleles was found, by comparison with the group control. Conclusions The HLA-DRB1 alleles could act alone or in combination with other genes to confer differential susceptibility and also protection to leprosy disease in endemic areas of the American continent.
Gender and variation in activity rates of hospital consultants
Authors: Bloor Karen , Freemantle Nick , Maynard Alan 
Published: February 2008

Objective To explore whether or not gender predicts consultant activity rates. Design Using data from the Hospital Episode Statistics for England 2004/2005, we explored inpatient activity rates of male and female hospital consultants, with and without adjustment for case-mix differences. As a sensitivity analysis we also explored outpatient attendances for male and female hospital consultants. Setting Data from the Hospital Episode Statistics for England. Main outcome measures Finished consultant episodes per year, with and without adjustment for case-mix differences, age and gender of consultant, contract held, hospital trust, specialty of practice, and clinical excellence awards, discretionary points and distinction awards. Results Including only consultants on full-time or maximum part-time contracts, men have significantly higher activity rates than women, after accounting for age, specialty and hospital trust. Conclusions The reasons for the different activity rates of male and female consultatns are unclear, but the implications of these results for the planning of the medical workforce are important.
Nanobiomaterials and Nanoanalysis: Opportunities for Improving the Science to Benefit Biomedical Technologies
Authors: Grainger D. W. , Castner D. G. 
Published: February 2008

AbstractNanomaterials advocated for biomedical applications must exhibit well‐controlled surface properties to achieve optimum performance in complex biological or physiological fluids. Dispersed materials with extremely high specific surface areas require as extensive characterization as their macroscale biomaterials analogues. However, current literature is replete with many examples of nanophase materials, most notably nanoparticles, with little emphasis placed on reporting rigorous surface analysis or characterization, or in formal implementation of surface property standards needed to validate structure‐property relationships for biomedical applications. Correlations of nanophase surface properties with their stability, toxicity and biodistributions are essential for in vivo applications. Surface contamination is likely, given their processing conditions and interfacial energies. Leaching adventitious adsorbates from high surface area nanomaterials is a possible toxicity mechanism. Polydimethylsiloxane (PDMS), long known as a ubiquitous contaminant in clean room conditions, chemical synthesis and microfabrication, remains a likely culprit in nanosystems fabrication, especially in synthesis, soft lithography and contact molding methods. New standards and expectations for analyzing the interfacial properties of nanoparticles and nano‐fabricated technologies are required. Surface science analytical rigor similar to that applied to biomedical devices, nanophases in microelectronics and heterogeneous catalysts should serve as a model for nanomaterials characterization in biomedical technologies.
Suzuki‐ and Heck‐Type Cross‐Coupling with Palladium Nanoparticles Immobilized on Spherical Polyelectrolyte Brushes
Authors: Proch S. , Mei Y. , Villanueva J. M. Rivera , Lu Y. , Karpov A. , Ballauff M. , Kempe R. 
Published: February 2008

AbstractWe report on a systematic study of the use of palladium nanoparticles immobilized on spherical polyelectrolyte brushes – Pd@SPB – for Heck‐ and Suzuki‐type coupling reactions. The spherical polyelectrolyte brush particles serving as carriers for the palladium nanoparticles consist of a solid polystyrene core with a radius of 46 nm onto which long chains of cationic polyelectrolytes are grafted. The palladium nanoparticles have directly been generated within this brush layer and the stabilization of the nanoparticles is effected by the colloidal carriers, no further surface stabilization is necessary. We demonstrate that these composite particles present robust catalysts for the Heck‐ and Suzuki‐type coupling reactions. This was shown by carrying out the Suzuki‐ and Heck‐type coupling reactions at relatively low temperatures (Suzuki reaction: 50 °C, Heck reaction: 70 °C). We demonstrate that the catalytic composite particles are not changed by these reaction conditions and retain their full activity for at least four runs. The yields obtained for both reactions are good to excellent. The mild operation conditions of the palladium nanoparticles are traced back to the absence of surface stabilization. Further mechanistic implications are discussed.
Functional Elastomers via Sequential Selective Diene Copolymerization/Hydrophosphorylation Catalysis
Authors: Ajellal Noureddine , Guillevic Erwan , Thomas Christophe M. , Jackstell Ralf , Beller Matthias , Carpentier Jean‐François 
Published: February 2008

AbstractAn effective preparation of new tailor‐made macromolecular materials via the combination of two fully atom‐efficient catalytic transformations is reported. First, new isoprene‐co‐1,3,7‐octatriene [P(IP‐co‐OT)] copolymers with controlled composition (2–21 mol% triene incorporated), molecular weight (Mn=23–102,000 g mol−1) and microstructure (1,4‐cis rich) have been prepared using the homogeneous Ziegler–Natta catalyst system composed of diallylneodynium chloride, magnesium chloride, tetrahydrofuran and methylaluminoxane [Nd(allyl)2Cl(MgCl2)2(THF)4/MAO]. Next, the pendant vinyl moieties in those P(IP‐co‐OT) copolymers have been selectively transformed into phosphonate groups by hydrophosphorylation in the presence of homogeneous rhodium phosphine catalysts. The latter hydrophosphorylation reaction has been optimized in terms of catalytic activity and selectivity, to define the conditions for an effective and safe procedure that does not affect the macromolecular architecture. All polymer materials have been microstructurally analyzed by 1H, 13C, and 31P NMR spectroscopy, to diagnose the catalyst selectivities in the copolymerization and hydrophosphorylation processes.
Palladium/Phosphite or Phosphate Catalyzed Oxidative Coupling of Arylboronic Acids with Alkynes to Produce 1,4‐Diaryl‐1,3‐butadienes
Authors: Horiguchi Hakaru , Tsurugi Hayato , Satoh Tetsuya , Miura Masahiro 
Published: February 2008

AbstractThe intermolecular oxidative coupling of arylboronic acids with internal alkynes efficiently proceeds in a 2:2 manner in the presence of palladium acetate, a triaryl phosphite or phosphate, and silver carbonate as catalyst, ligand, and oxidant, respectively, to produce the corresponding 1,4‐diaryl‐1,3‐butadiene derivatives.
Consolidation of sheared, strongly flocculated suspensions
Authors: Holmqvist Claes , Dahlkild Anders 
Published: February 2008

AbstractThe concept of a particle concentration dependent yield stress, previously employed in studies of uniaxial consolidation of a flocculated solid phase dispersed in a liquid, is extended to comprise flocculated phase shear strength. The inter‐particle stresses are modeled by assuming that the stress state is always located on a yield‐surface in stress‐space, whose form is adopted from the Cam‐clay plasticity theory for the quasi‐static consolidation of soil. By treating the time‐dependent dewatering of a suspension trapped between a permeable filter and a sliding piston, as well as the asymptotic limit of a cross‐flow filtration situation, the differences with respect to the conventional uniaxial models are made apparent, and the effects of the shear stresses on the consolidation process are elucidated. Applying shear is predicted to increase the rate of the drainage process, because of a reduced load bearing capacity of the flocculated phase, and the correspondingly higher pore pressures. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Kinetics and equilibrium of gas adsorption on RPM1‐Co and Cu‐BTC metal‐organic frameworks: Potential for gas separation applications
Authors: Krungleviciute V. , Lask K. , Migone A. D. , Lee J.‐Y. , Li J. 
Published: February 2008

AbstractWe report on the results of kinetic and equilibrium adsorption measurements for two gases, CF4 and Ar, on RPM1‐Co and Cu‐BTC metal‐organic framework materials. The kinetic experiments were performed at similar relative temperatures (T/Tcritical = 0.52 and 0.597) on both adsorbents. The results show that both gases behave differently on Cu‐BTC from the way they do on RPM1‐Co. In addition, the equilibrium isotherms indicate that there are some sites on Cu‐BTC which are accessible to Ar but not to CF4. Taken together, our results for the kinetic and equilibrium experiments suggest that these MOFs have high potential for use in gas separation applications. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Correlations of supercritical temperature of fluid alkali metals
Authors: Balasubramanian Ramasamy 
Published: February 2008

AbstractThe supercritical temperature, the maximum attainable temperature of superheating and the critical compressibility factor of caesium, rubidium and potassium are correlated through the generalised van der Waals equation of state. This three‐parameter equation differs from the known van der Waals equation of state by the modified expression for molecular pressure. For caesium, rubidium and potassium, the ratios of the supercritical temperature to the maximum attainable temperature of superheating are estimated. Our estimation results are in agreement with experimental data. It has been established that caesium, rubidium and potassium obey the single‐parameter law of corresponding states with the ratio of the supercritical temperature to the maximum attainable temperature of superheating as the thermodynamic similarity parameter. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd.
Effects of extrusion conditions on the properties of recycled poly(ethylene terephthalate)/nanoclay nanocomposites prepared by a twin‐screw extruder
Authors: Giraldi A. L. F. de M. , Bizarria M. T. M. , Silva A. A. , Velasco J. I. , d'Ávila Marcos A. , Mei L. H. I. 
Published: February 2008

AbstractThe effects of extrusion conditions on the mechanical properties of recycled poly(ethylene terephthalate) (rPET)/clay nanocomposites were studied. Nanocomposites of recycled PET containing 2.5 and 5.0 wt % of montmorillonite modified with organophilic quaternary ammonium salt (DELLITE 67G) were prepared by melt compounding using a corotating twin‐screw type extruder at two different screw rotation speeds: 250 and 150 rpm. The highest value of Young's modulus was found for low screw rotation speed (150 rpm). Morphological analysis using transmission electron microscopy (TEM) revealed the presence of fully exfoliated clay platelets in samples prepared at 150 rpm. It was concluded that the screw rotation speed should be optimized when preparing recycled PET/clay nanocomposites by melt compounding. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Effect of Li+ ions on structure, properties, and actuation of cellulose electro‐active paper actuator
Authors: Nayak Jyoti N. , Chen Yi , Yun Sungryul , Kim Jaehwan 
Published: February 2008

AbstractWe have reported an electro‐active paper actuator from regenerated cellulose. After dissolving cellulose fibers with a solution of lithium chloride in N,N‐dimethylacetamide, cellulose was regenerated by combining distillation of cellulose solution along with washing with the mixture of deionized water, isopropyl alcohol, and running water. However, the effect of Li+ ions on structure, properties, and the actuation behavior of the actuator was not studied. This article describes the changes in these parameters when the Li+ ions are removed by subjecting it to different running water exposure time. The structure and properties of cellulose electro‐active paper and its actuation behavior were studied. As Li+ ions content reduced from 4354.17 to 10.26 ppm by increasing the exposure time of running water, crystallinity, Young's modulus, and bending displacement decreased. Details about the investigation have been explained. This elimination of ions is important to increase the piezoelectric effect in EAPap by decreasing the ion migration effect. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008