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1.
Cerebral microbleeds and cognitive decline in a hemodialysis patient: Case report and review of literature 下载免费PDF全文
Lin Li Mark Fisher Wei‐Ling Lau Hamid Moradi Alexander Cheung Gaby Thai Jason Handwerker Kamyar Kalantar‐Zadeh 《Hemodialysis international. International Symposium on Home Hemodialysis》2015,19(3):E1-E7
Cerebral microbleeds (CMBs) are small hemosiderin deposits indicative of prior cerebral microscopic hemorrhage and previously thought to be clinically silent. Recent population‐based cross‐sectional studies and prospective longitudinal cohort studies have revealed association between CMB and cognitive dysfunction. In the general population, CMBs are associated with age, hypertension, and cerebral amyloid angiopathy. In the chronic kidney disease (CKD) population, diminished estimated glomerular filtration rate has been found to be an independent risk factor for CMB, raising the possibility that a uremic milieu may predispose to microbleeds. In the end‐stage renal disease (ESRD) population on hemodialysis, the incidence of microbleeds is significantly higher compared with a control group without history of CKD or stroke. We present an ESRD patient on chronic hemodialysis with a history of gradual cognitive decline and progressive CMBs. Through this case and literature review, we illustrate the need to develop detection and prediction models to treat this frequent development in ESRD patients. 相似文献
2.
Caleb Acquah Yi Wei Chan Charles K. S. Moy Clarence M. Ongkudon Sie Yon Lau 《分离科学与技术》2018,53(13):2100-2111
The introduction of aptameric ligands onto disk-monolithic adsorbent, representing a unique strategy for convective isolation of target molecules with high specificity and selectivity, is investigated for the first time. Experimental results showed that the disk monolith possessed a good permeability of 1.67 ± 0.05 × 10–14 m2 (RSD = 3.2%). The aptameric ligand density for the aptamer-modified disk monolith was 480 pmol/uL. Chromatographic analysis of the aptamer disk-monolith efficiency showed an optimum linear velocity of 126 cm/min (≈0.25 mL/min) at room temperatures 25 ± 2°C. The theoretical number of plates corresponding to the optimum linear velocity was 128.2 with an height equivalent to the theoretical plate of 0.022 mm. The disk aptamer-immobilised monolithic system demonstrated good selectivity and isolation of thrombin from non-targets. 相似文献
3.
Ke Qi Lau Mohd Redzwan Sabran Siti Raihanah Shafie Sook Wah Chan 《International Journal of Food Science & Technology》2022,57(7):4586-4593
Sugarcane bagasse (SB) is one of the most abundant food wastes. In this research, SB was incorporated into the development of noodles at three different ratios, i.e. 5%, 10% and 15%. Total dietary fibre of noodles significantly increased from 3.39% (control noodles; – without SB) to 13.85% with 15% SB incorporation. All SB incorporated noodles (SBNs) were qualified to be labelled as ‘High in dietary fibre’. The 15% SBN had the highest fibre content and lowest dialyzable glucose, but the organoleptic properties were the lowest. Due to that, 5% SBN was deemed to be the most suitable ratio for noodles incorporation, as it had the closest value towards the commercial noodles in terms of colour, texture, fibre content and dialyzable glucose concentration of noodles samples. In terms of sensory evaluation, the 5% SBN had the highest overall acceptability, and the ratio was suitable for noodles development. 相似文献
4.
Yeuk T. Lau Ka M. Ng Na Chen David T. W. Lau Kam M. Ko Ping C. Leung Christianto Wibowo 《American Institute of Chemical Engineers》2014,60(12):4014-4026
A quality assurance (QA) procedure for multiple‐herb extraction, which takes into account the existence of common chemical markers and multiple‐herb‐extraction effects, has been developed for producing Chinese herbal medicines (CHMs) of consistent quality. The experimental method for determining related correlation function of the multiple‐herb‐extraction effect was designed. A systematic solution strategy was also developed to appropriately decompose the multiple‐herb extraction system into several subsystems for obtaining solution(s) and determining the overall behavior of the system. An example of QA of Danshen–Gegen (DG) decoction was used to demonstrate the QA procedure. An H9c2 cell assay was used to test the efficacy of consistent quality DG decoctions prepared by different herb combinations with different material costs of herbs. It was observed that a multiple‐herb‐extraction effect was present in the aqueous extraction of Danshensu and this effect was depended on the extraction solvent. The possible mechanism of this multiple‐herb‐extraction effect in the aqueous DG extraction was speculated to be the change of initial pH value of the aqueous extraction solvent by an unknown component from Gegen. The experimental chemical marker concentrations fell within ±10% of the specified chemical marker compositions by using the amount of herb from each herb class as predicted by the QA model. Furthermore, an H9c2 cell assay was used to test the efficacy of three consistent quality DG extracts, which were produced by different herb combinations with different material costs of herbs. The results showed that the three DG extracts provided consistent biological efficacy against menadione‐induced toxicity. This study extended a recently developed QA procedure of single‐herb extraction to multiple‐herb extraction. It provides a solution of QA in extraction, which is one of the most important unresolved problems in the modernization of traditional Chinese medicines. With this modified model and the companion experiments, the amount of herbs needed from different quality classes to produce a multiple‐herb formula CHM product decoction with consistent quality can be exactly determined. © 2014 American Institute of Chemical Engineers AIChE J 60: 4014–4026, 2014 相似文献
5.
Linear Aliphatic Dialkynes as Alternative Linkers for Double‐Click Stapling of p53‐Derived Peptides 下载免费PDF全文
Yu Heng Lau Dr. Peterson de Andrade Dr. Grahame J. McKenzie Prof. Ashok R. Venkitaraman Prof. David R. Spring 《Chembiochem : a European journal of chemical biology》2014,15(18):2680-2683
We investigated linear aliphatic dialkynes as a new structural class of i,i+7 linkers for the double‐click stapling of p53‐based peptides. The optimal combination of azido amino acids and dialkynyl linker length for MDM2 binding was determined. In a direct comparison between aliphatic and aromatic staple scaffolds, the aliphatic staples resulted in superior binding to MDM2 in vitro and superior p53‐activating capability in cells when using a diazidopeptide derived from phage display. This work demonstrates that the nature of the staple scaffold is an important factor that can affect peptide bioactivity in cells. 相似文献
6.
Functional Chromatography Reveals Three Natural Products that Target the Same Protein with Distinct Mechanisms of Action 下载免费PDF全文
Dr. Min Jin Kang Dr. Tongde Wu Dr. E. M. Kithsiri Wijeratne Eric C. Lau Damian J. Mason Celestina Mesa Joseph Tillotson Prof. Dr. Donna D. Zhang Prof. Dr. A. A. Leslie Gunatilaka Dr. James J. La Clair Prof. Dr. Eli Chapman 《Chembiochem : a European journal of chemical biology》2014,15(14):2125-2131
Access to lead compounds with defined molecular targets continues to be a barrier to the translation of natural product resources. As a solution, we developed a system that uses discrete, recombinant proteins as the vehicles for natural product isolation. Here, we describe the use of this functional chromatographic method to identify natural products that bind to the AAA+ chaperone, p97, a promising cancer target. Application of this method to a panel of fungal and plant extracts identified rheoemodin, 1‐hydroxydehydroherbarin, and phomapyrrolidone A as distinct p97 modulators. Excitingly, each of these molecules displayed a unique mechanism of p97 modulation. This discovery provides strong support for the application of functional chromatography to the discovery of protein modulators that would likely escape traditional high‐throughput or phenotypic screening platforms. 相似文献
7.
Thin-walled channel sections may buckle in a distortional mode when subjected to compression. A variety of cold-formed channel columns were tested recently to study distortional buckling in the inelastic range. This paper describes a comparison of a theoretical method for predicting the inelastic distortional buckling strengths of thin-walled columns with the column tests. The method is based on a spline finite strip buckling analysis which takes into account the non-linear stress-strain behaviour of the steel making up the test sections, and the fix-ended test conditions. The inelastic buckling analysis is found to produce accurate estimates of the test failure loads and failure modes 相似文献
8.
The first step in evaluating the visual performance and energy efficiency provided by daylight requires an accurate estimation of the amount of daylight entering a building. The actual daylight illuminance of a room is mainly influenced by the luminance levels and patterns of the sky in the direction of view of the window at that time. The daylight coefficient concept, which considers the changes in the luminance of the sky elements, offers a more effective way of computing indoor daylight illuminances. Recently, Kittler et al. have proposed a new range of 15 standard sky luminance distributions including the CIE (International Commission on Illumination) standard clear sky. Lately, these 15 sky luminance models have been adopted as the CIE Standard General Skies. This paper presents a graphical method to calculate interior illuminance for the CIE standard clear sky using the daylight coefficient approach. The simplified techniques in the form of a nomograph and Waldram diagram were established and described. The performance of the proposed approach was evaluated against the results obtained by an independent calculation approach and a computer simulation program. It was shown that the daylight illuminances estimated by our graphical tool were in reasonably good agreement with those produced from the other two methods. The findings provide building professionals and students a reliable and simple alternative that incorporates the daylight coefficient concept to estimate the interior daylight illuminance and assess daylighting performance. 相似文献
9.
NOM removal by adsorption onto granular ferric hydroxide: Equilibrium, kinetics, filter and regeneration studies 总被引:3,自引:0,他引:3
Adsorption onto granular ferric hydroxide (GFH) with subsequent in-situ regeneration is studied as a new process for natural organic matter (NOM) removal from groundwater. Adsorbent equilibrium loadings of 10-30 mgDOC g(-1)GFH(-1) are obtained, whereas the non-adsorbable DOC fraction amounts to 1.5 mgL(-1) for all investigated groundwaters. The larger and UV-active NOM fractions (mainly fulvic acids) are well adsorbed while the smaller molecular fractions are poorly or not adsorbed. However, kinetic studies show that the smaller and medium-sized fulvic acids are removed first. The equilibrium is strongly dependent on pH but only weakly on ionic strength, pointing to ligand exchange as the dominant adsorption mechanism. With regard to NOM structure, prerequisites for adsorption onto GFH are both a minimum number of functional groups and a molecular size small enough to enter the GFH pores. NOM breakthrough curves are successfully simulated using the LDF model (homogeneous surface diffusion model (HSDM) with linear driving force approach for surface diffusion) and experimentally determined mass transfer coefficients. Regeneration of loaded GFH is possible either by use of NaOH or oxidatively by H(2)O(2). The optimal quantities and concentrations are determined. 相似文献
10.
Experiments were conducted in an annular flume using a commercially available kaolinite clay as well as contaminated bed sediment from Hamilton Harbour (Ontario) to assess their stability against erosion. Critical shear stress for erosion was measured under different conditions of bed formation (quiescently deposited beds and shear deposited beds) as well as with and without the presence of a biostabilized bed. Results suggest that a biostabilized bed and a bed formed under a flowing condition, similar to a river scenario, will be more resistant against erosion than will a non-biostabilized bed and a bed formed under quiescent conditions. Up to three cycles of erosion and flocculation/deposition were observed to occur within one experiment. These results suggest that the depositional history and biostabilization of river bed sediments need to be seriously considered within sediment and contaminant transport models if meaningful estimates of sediment and contaminant source, fate and effect are to be generated and used for the management of our aquatic ecosystems. 相似文献