Improving the mapping of condition-specific health-related quality of life onto SF-6D score

Background This study sought to improve the predictive performance and goodness-of-fit of mapping models, as part of indirect valuation, by introducing cubic spline smoothing to map a group of health-related quality of life (HRQOL) measures onto a preference-based measure. Methods This study was a secondary analysis of a cross-sectional health survey data assessing the HRQOL for patients with colorectal neoplasms. Mapping functions of condition-specific functional assessment of cancer therapy—colorectal (FACT-C) onto preference-based SF-6D measure were developed using a dataset of 553 Chinese subjects with different stages of colorectal neoplasm. The missing values of FACT-C were imputed using multiple imputation. Then three widely applicable models (ordinary least square (OLS), Tobit and two-part models) were employed for the mapping function after applying the cubic spline smoothing on the data. For the evaluation of the effectiveness of cubic spline smoothing and multiple imputation, the goodness-of-fit and prediction performance of each model were compared. Results Analyses showed that the models fitted with transformed data from cubic spline smoothing offered better performance in goodness-of-fit and prediction than the models fitted with the original data. The values of $R^2$ were improved by over 10 %, and the root mean square error and the mean absolute error were both reduced. The best goodness-of-fit and performance were achieved by OLS model using transformed data from cubic spline smoothing. Conclusions Cubic spline smoothing and multiple imputation were recommended for the mapping of HRQOL measures onto the preference-based measure. Among the three mapping models, the simple-to-use OLS model had the best performance.postprin

Material Selection for Donor Materials in Small Molecular-Based Bulk Heterojunction Organic Photovoltaic Devices

Poster Presentation: S15- Metal Complexes for Optics: from fundamental to applications: no. S15.P23published_or_final_versio

Intestinal pseudoobstruction is an uncommon but important clinical manifestation of systemic lupus erythematosus (SLE)

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A comparison of the performance of the Assessment of SpondyloArhritis international Society (ASAS) classification criteria, European Spondyloarthropathy Study Group (ESSG) classification criteria, and Modified New York (MNY) criteria in a cohort of Chinese spondyloarthritis patients

BACKGROUND: The existing Modified New York (MNY) criteria and European Spondyloarthropathy Study Group (ESSG) criteria are defective in early diagnosis of patients with spondyloarthritis. The objective of this study was to reclassify a Chinese cohort of patients with previous expert-diagnosed spondyloarthritis according to the recently issued Assessment of SpondyloArthritis international Society (ASAS) classification criteria for axial spondyloarthritis and the two existing criteria, the ESSG criteria and MNY criteria and to compare the clinical characteristics including disease duration, disease activity, and spinal mobility between patients fulfilling these criteria. METHODS: Consecutive patients diagnosed by expert opinion from a tertiary centre were classified into three groups: the Ankylosing Spondyloarthritis (AS) by MNY criteria; undifferentiated spondyloarthritis (USpA) by ESSG criteria (USpA/ESSG), and those by ASAS classification criteria only (USpA/ASAS). Functional status was studied by Bath Ankylosing Spondylitis Functional Index (BASFI). Disease activity was evaluated by Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and C-reactive protein. Spinal mobility including modified Schober test and chest expansion was determined. RESULTS: A total of 128 spondyloarthritis patients (92 male and 36 female) were recruited. USpA/ASAS group identified patients with shortest disease duration (9.2±2.3 years, 11.6±3.8, 18.7±2.2 years in USpA/ASAS group, USpA group, and AS group respectively; P<0.01). USpA/ASAS and USpA/ESSG groups were better than AS group in terms of BASFI, modified Schober test and chest expansion. C-reactive protein and BASDAI were similar in the three groups. CONCLUSION: The ASAS classification criteria are shown to identify spondyloarthritis patients at an earlier stage when spinal mobility and functional status are preserved. This group of USpA patients demonstrated comparable disease activity to other groups, suggesting a need and predictably better outcome for early treatment.published_or_final_versionThe 15th Medical Research Conference (15th MRC), Department of Medicine, University of Hong Kong, Hong Kong, 16 January 2010. In Hong Kong Medical Journal, 2010, v. 16 n. 1, suppl. 1, p. 18, abstract no. 2

Characterization of Burkholderia cepacia genomovar I as a potential biocontrol agent of Ganoderma boninense in oil palm

Burkholderia is an important bacterial genus containing several species of ecological, biotechnological and pathological interest. Bacterial isolate can be gotten from soil, water, plants and even clinics. With their taxonomy undergoing constant revision and the phenotypic similarity of several species, correct identification of Burkholderia is difficult. Burkholderia cepacia complex (Bcc) consists of nine discrete genomic species and a genetic scheme based on the recA gene has greatly enhanced the identification of B. cepacia complex species. The objectives of this study were to identify Burkholderia strain UPM B3 which was isolated from oil palm roots to the species level based on Biolog&#174; Identification System, and to carry out DNA fingerprinting for strain differentiation as well as differentiate between pathogenic and non-pathogenic human forms. Antagonistic activity of UPM B3 against Ganoderma boninense was alsoevaluated by using dual culture and poison food tests. Genotype characterization was carried out by amplification of the recA gene using specific primers, purified using QIA Quick polymerase chain reaction (PCR) purification kit and sequenced. Multiple sequence alignments were performed on closely related sequence accessions using CLUSTAL W software. Result of nucleotide sequencing followed by phylogenetic analysis of the recA fragments differentiated both putative and known Burkholderiaspecies and all members of the B. cepacia complex. Genomovar analysis confirmed that UPM B3, isolated from oil palm roots belongs to genomovar I and has antagonistic activity against G. boninense based on in vitro dual culture and poison food tests. From the phylogenetic tree, UPM B3 is a specific strain within B. cepacia complex species that belong to genovomar I which is associated with strains nonpathogenic to humans. Thus, B. cepacia strain UPM B3 has the potential to be used against G.boninense, the causal pathogen of basal stem rot (BSR) in oil palm

Outcome measures of chronic arthritis in Hong Kong: comparison of the AIMS2 (Chinese) and WHO quality of life - brief form (WHOQOL-BREF) (HK)

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Bipolar gold(III) complexes for solution-processable organic light-emitting devices with a small efficiency roll-off

Poster: no. 12A new class of bipolar alkynylgold(III) complexes containing triphenylamine and benzimidazole moieties has been synthesized and fully characterized. The incorporation of methyl groups in the central phenyl unit has been found to rigidify the molecule to reduce non-radiative decay, yielding a high photoluminescence quantum yield of up to 75 % in spin-coated thin films. More importantly, this class of alkynylgold(III) complexes exhibits excellent solubility in various organic solvents and is capable of serving as phosphorescent dopants in the fabrication of solution-processable organic lightemitting devices (OLEDs). Efficient solution-processable OLEDs with high external quantum efficiency (EQE) of up to 10 % and an extremely small efficiency roll-off of less than 1 % at a practical brightness of 1000 cd m–2 have been demonstrated.published_or_final_versio

Interactions between organic friction modifier additives

The interactions of different additives in engine oils can create synergistic or antagonistic effects. This paper studies how mixing different organic friction modifier additives affects friction reducing properties of lubricants in the boundary lubrication regime. Amines of different degree of saturation were mixed with either glycerol monooleate (GMO) or oleic acid in hexadecane. The model lubricants thus formed were characterised with Fourier-transform infrared spectroscopy. Friction tests in reciprocating motion using ball-on-disc steel-steel contacts were conducted to examine the tribological performance of these lubricants. Worn surfaces were examined using X-ray photoelectron spectroscopy. Oleic acid and oleylamine, a primary amine. Were found to form a partial ionic liquid, providing synergistic friction reduction. This positive interaction reduces with increasing degree of saturation of the amine. No synergistic effect was observed between GMO and oleylamine,suggesting that GMO does not hydrolyse into a carboxylic acid within a rubbing contact in the presence of amine. Keywords: Boundary Lubrication, Additives, Friction Abbreviations: organic friction modifier (OFM); glycerol monooleate (GMO); ionic liquid (IL); oleylamine (OA); diocylamine (DA); trihexylamine (TA); dimethylhexadecaylamine (DM16); high frequency reciprocating rig (HFRR); X-ray photoelectron spectroscopy (XPS)

Effect of oral erythromycin on gastric and small bowel transit time of capsule endoscopy

Aim: To determine the effect of oral erythromycin on gastric and small bowel transit time of capsule endoscopy. Methods: Consecutive patients who underwent capsule endoscopy during the 16-mo study period were either given 250 mg oral erythromycin, 1 h prior to swallowing the capsule endoscope or nothing. The gastric and small bowel transit time, and the small bowel image quality were compared. Results: Twenty-four patients received oral erythromycin whereas 14 patients were not given any prokinetic agent. Patients who received erythromycin had a significantly lower gastric transit time than control (16 min vs 70 min, P = 0.005), whereas the small bowel transit time was comparable between the two groups (227 min vs 183 min, P = 0.18). Incomplete small bowel examination was found in three patients of the control group and in one patient of the erythromycin group. There was no significant difference in the overall quality of small bowel images between the two groups. A marked reduction in gastric transit time was noted in two patients who had repeat capsule endoscopy after oral erythromycin. Conclusion: Use of oral erythromycin significantly reduces the gastric transit time of capsule endoscopy. © 2005 The WJG Press and Elsevier Inc. All rights reserved.published_or_final_versio

The clinical course of polymyalgia rheumatica in Chinese

Polymyalgia rheumatica (PMR) is diagnosed based on clinical features that may overlap with other rheumatic conditions like rheumatoid arthritis (RA). Furthermore, a proportion of PMR patients may subsequently evolve into RA. The aim of this study was to examine the clinical characteristics of PMR patients in a Chinese cohort compared to a Caucasian series. Patients diagnosed to have PMR during 1997-2008 were reviewed for clinical features and compared to a reported Caucasian series. Rheumatoid factor (RF) and anticyclic citrullinated peptide (CCP) antibodies were determined by immunonephelometry and enzyme-linked immunosorbent assay, respectively. Forty-four patients of southern Chinese origin were diagnosed to have PMR according to specialist opinion. Seventy-five percent of patients (n = 33) were >65 years of age at diagnosis (mean ± standard deviation, 75.8 ± 9.6 years). The commonest feature at disease onset was elevated erythrocyte sedimentation rate >40 mm/h (100% vs. 95.7%; p = 0.17) and bilateral shoulder pain or stiffness (95.5% vs. 90.8%; p = 0.31), comparable in frequency to the Caucasian cohort. However, Chinese patients had significantly longer duration of symptoms before diagnosis (p < 0.001) but less bilateral upper arm tenderness (p < 0.001) and generalized stiffness (p = 0.01). Twelve (27.3%) patients evolved into RA after a median duration of 2 months from onset of PMR. RF and anti-CCP antibodies were positive in 66.7% and 60% of these patients compared to 9.4% and 6.2%, respectively, among those who did not evolve into RA during the period observed. Chinese patients with PMR have modestly different clinical profile compared to the Caucasian counterpart. RF and anti-CCP antibodies were more likely to be present in those who subsequently developed into RA. © 2009 Clinical Rheumatology.postprin