Detection of Clostridium perfringens and its toxinotypes by enzyme Linked immunosorbent assay from enterotoxaemic goats in Bangladesh

( K. B. M. S. Islam ),( M. S. Rahman ),( Md. Ershaduzzaman ),( M. J. F. A. Taimur ),( Hyung Kwan Jang ),( Hee Jong Song ) 한국가축위생학회 2010 韓國家畜衛生學會誌 Vol.33 No.1

An enzyme-linked immnnosorbent assay (ELISA) has been performed for the detection of the prevailing toxinotypes of Clostridium perfringens obtained from conventional culturing of intestinal contents of goats which have died of suspected enterotoxaemia. The test was found effective to detect the toxins as well as types of the organism with less time and labor. The most prevailing type of C. perfringens causing enterotoxaemia in goat was C. perfringens type D (68.75%) and followed by C. perfringens type B (25%) and C (6.25%). No C. perfringens type A was detected. This study showed an intelligible picture of prevailing toxinotypes of C. perfringens in goats in Bangladesh. The use of the ELISA for the detection of clostridial types and toxins allows the differential diagnosis of C. perfringens types A, B, C and D enterotoxaemias from samples of intestinal contents and the typing of cultures of C. perfringens.

Actual microstructure-based numerical method for mesomechanics of concrete

S. Chen,A. K. H. Kwan,Z.Q. Yue 사단법인 한국계산역학회 2013 Computers and Concrete, An International Journal Vol.12 No.1

This paper presents an actual microstructure-based numerical method to investigate the mechanical properties of concrete at mesoscopic level. Digital image processing technique is used to capture the concrete surface image and generate the actual 3-phase microstructure of the concrete, which consists of aggregate, matrix and interfacial transition zones. The microstructure so generated is then transformed into a mesh or grid for numerical analysis. A finite difference code FLAC2D is used for the numerical analysis to simulate the mechanical responses and failure patterns of the concrete. Several cases of concrete with different degrees of material heterogeneity and under different compression loading conditions have been analysed. From the numerical results, the effects of the internal material heterogeneities as well as the external confining stresses are studied. It is shown that the material heterogeneities arising from the presence of different phases and the existence of interfacial transition zones have great influence on the overall mechanical behaviour of concrete and that the numerically simulated behaviour of concrete with or without confining stresses applied agrees quite well with the general observations reported in the literature.

Plenary Session l : Efficacy and Safety of Tenofovir DF (TDF) in Chronic Hepatitis B Virus Infected Patients with Documented Lamivudine Resistance (LAM-R)

( S Fung ),( P Kwan ),( A Horban ),( M Pelemis ),( P Husa ),( H W Hann ),( Jf Flaherty ),( B Massetto ),( P Dinh ),( A Corsa ),( K Kitrinos ),( Jg Mchutchison ),( M Fabri ),( E Gane ) 대한간학회 2013 춘·추계 학술대회 (KASL) Vol.2013 No.1

Background: Efficacy and safety of tenofovir DF (TDF) have been demonstrated over 6 years in pivotal HBV studies, but have yet to be established in lamivudine-resistant (LAM-R) patients in a prospective, randomized trial. Methods: Phase 3b, double-blind, randomized (1:1) comparison of TDF and emtricitabine (FTC)/TDF in chronic HBV patients on LAM at screening with HBV DNA ≥103 IU/mL and documented LAM-R (rtM204V/I±rtL180M; INNO-LiPA HBV v2/ v3). Patients were stratified by ALT (≥ or <2×ULN) and HBeAg status. Efficacy and safety, including bone mineral density (BMD) monitoring by DXA were assessed over 96 weeks. Results: Of 280 randomized and treated patients, 133/141 (94%) and 125/139 (90%) in TDF and FTC/TDF groups completed 96 weeks. Groups were well matched: mean age 47 years, 75% males, 34% Asian, 47% HBeAg+, 42% ALT <ULN; HBV genotypes: 22% A, 14% B, 19% C, and 45% D. By ITT analysis, missing=failure, 89% and 86% receiving TDF and FTC/TDF, respectively, had HBV DNA <400 copies/mL at Week 96 (P =0.43); 70% in each arm had normal ALT. HBeAg loss was observed in 10/65 (15%) and 9/68 (13%) in TDF and FTC/TDF arms, respectively. One patient (FTC/TDF) had HBsAg loss without seroconversion. Both treatments were well tolerated with 1% (3/280) discontinuing for adverse event (1 TDF, 2 FTC/TDF). No patients had confirmed increase in serum creatinine of ≥0.5 mg/dL, and 1% (2 TDF) had serum phosphorus <2 mg/dL. BMD of spine and hip revealed no clinically relevant bone loss, and there were no non-traumatic fractures reported. No TDF resistance was detected through 96 weeks. Conclusions: A high rate of HBV DNA suppression with no detectable TDF resistance was achieved with TDF monotherapy in LAM?R patients through 96 weeks. TDF was safe and well tolerated, with a low rate of renal events and no evidence of clinically relevant bone loss.

Detection of Clostridium perfringens and its toxinotypes by enzyme linked immunosorbent assay from enterotoxaemic goats in Bangladesh

Islam, K.B.M.S.,Rahman, M.S.,Ershaduzzaman, Md.,Taimur, M.J.F.A.,Jang, Hyung-Kwan,Song, Hee-Jong The Korean Society of Veterinary Service 2010 韓國家畜衛生學會誌 Vol.33 No.1

An enzyme-linked immnnosorbent assay (ELISA) has been performed for the detection of the prevailing toxinotypes of Clostridium perfringens obtained from conventional culturing of intestinal contents of goats which have died of suspected enterotoxaemia. The test was found effective to detect the toxins as well as types of the organism with less time and labor. The most prevailing type of C. perfringens causing enterotoxaemia in goat was C. perfringens type D (68.75%) and followed by C. perfringens type B (25%) and C (6.25%). No C. perfringens type A was detected. This study showed an intelligible picture of prevailing toxinotypes of C. perfringens in goats in Bangladesh. The use of the ELISA for the detection of clostridial types and toxins allows the differential diagnosis of C. perfringens types A, B, C and D enterotoxaemias from samples of intestinal contents and the typing of cultures of C. perfringens.

Mass optimization of four bar linkage using genetic algorithms with dual bending and buckling constraints

M.R.A. Hassan,I.A. Azid,M. Ramasamy,J. Kadesan,K.N. Seetharamu,A.S.K. Kwan,P. Arunasalam 국제구조공학회 2010 Structural Engineering and Mechanics, An Int'l Jou Vol.35 No.1

In this paper, the mass optimization of four bar linkages is carried out using genetic algorithms (GA) with single and dual constraints. The single constraint of bending stress and the dual constraints of bending and buckling stresses are imposed. From the movement response of the bar linkage mechanism, the analysis of the mechanism is developed using the combination of kinematics, kinetics, and finite element analysis (FEA). A penalty-based transformation technique is used to convert the constrained problem into an unconstrained one. Lastly, a detailed comparison on the effect of single constraint and of dual constraints is presented.

Flexural ductility of prestressed concrete beams with unbonded tendons

F.T.K. Au,K.H.E. Chan,A.K.H. Kwan,J.S. Du 사단법인 한국계산역학회 2009 Computers and Concrete, An International Journal Vol.6 No.6

Based on a numerical method to analyse the full-range behaviour of prestressed concrete beams with unbonded tendons, parametric studies are carried out to investigate the influence of 11 parameters on the curvature ductility of unbonded prestressed concrete (UPC) beams. It is found that, among various parameters studied, the depth to prestressing tendons, depth to non-prestressed tension steel, partial prestressing ratio, yield strength of non-prestressed tension steel and concrete compressive strength have substantial effects on the curvature ductility. Although the curvature ductility of UPC beams is affected by a large number of factors, rather simple equations can be formulated for reasonably accurate estimation of curvature ductility. Conversion factors are introduced to cope with the difference in partial safety factors, shapes of equivalent stress blocks and the equations to predict the ultimate tendon stress in BS8110, EC2 and ACI318. The same equations can also be used to provide conservative estimates of ductility of UPC beams with compression steel.

Mass optimization of four bar linkage using genetic algorithms with dual bending and buckling constraints

Hassan, M.R.A.,Azid, I.A.,Ramasamy, M.,Kadesan, J.,Seetharamu, K.N.,Kwan, A.S.K.,Arunasalam, P. Techno-Press 2010 Structural Engineering and Mechanics, An Int'l Jou Vol.35 No.1

In this paper, the mass optimization of four bar linkages is carried out using genetic algorithms (GA) with single and dual constraints. The single constraint of bending stress and the dual constraints of bending and buckling stresses are imposed. From the movement response of the bar linkage mechanism, the analysis of the mechanism is developed using the combination of kinematics, kinetics, and finite element analysis (FEA). A penalty-based transformation technique is used to convert the constrained problem into an unconstrained one. Lastly, a detailed comparison on the effect of single constraint and of dual constraints is presented.

Impact of uncertain natural vibration period on quantile of seismic demand

H.P. Hong,S.S. Wang,A.K.H. Kwan 국제구조공학회 2008 Structural Engineering and Mechanics, An Int'l Jou Vol.28 No.4

This study investigates effect of uncertainty in natural vibration period on the seismic demand. It is shown that since this uncertainty affects the acceleration and displacement responses differently, two ratios, one relating peak acceleration responses and the other relating the peak displacement responses, are not equal and both must be employed in evaluating and defining the critical seismic demand. The evaluation of the ratios is carried out using more than 200 strong ground motion records. The results suggest that the uncertainty in the natural vibration period impacts significantly the statistics of the ratios relating the peak responses. By using the statistics of the ratios, a procedure and sets of empirical equations are developed for estimating the probability consistent seismic demand for both linear and nonlinear systems.

Impact of uncertain natural vibration period on quantile of seismic demand

Hong, H.P.,Wang, S.S.,Kwan, A.K.H. Techno-Press 2008 Structural Engineering and Mechanics, An Int'l Jou Vol.28 No.4

This study investigates effect of uncertainty in natural vibration period on the seismic demand. It is shown that since this uncertainty affects the acceleration and displacement responses differently, two ratios, one relating peak acceleration responses and the other relating the peak displacement responses, are not equal and both must be employed in evaluating and defining the critical seismic demand. The evaluation of the ratios is carried out using more than 200 strong ground motion records. The results suggest that the uncertainty in the natural vibration period impacts significantly the statistics of the ratios relating the peak responses. By using the statistics of the ratios, a procedure and sets of empirical equations are developed for estimating the probability consistent seismic demand for both linear and nonlinear systems.

Promoter methylation of the Wnt/β‐catenin signaling antagonist <i>Dkk‐3</i> is associated with poor survival in gastric cancer

Yu, Jun,Tao, Qian,Cheng, Yuen Y.,Lee, Kwan Y.,Ng, Simon S. M.,Cheung, Kin F.,Tian, Linwei,Rha, Sun Y.,Neumann, Ulf,Rö,cken, Christoph,Ebert, Matthias P. A.,Chan, Francis K. L.,Sung, Joseph J. Y. Wiley Subscription Services, Inc., A Wiley Company 2009 Cancer Vol.115 No.1

<P><B>Abstract</B></P><P><B>BACKGROUND:</B></P><P>Abnormal activation of the Wnt/β‐catenin signaling pathway is common and critical in the pathogenesis of digestive cancers. In this study, the authors investigated the promoter methylation of the dickkopf homolog 3 gene <I>Dkk‐3</I> in these cancers and its prognostic significance in gastric cancer.</P><P><B>METHODS:</B></P><P><I>Dkk‐3</I> methylation was assessed in 173 patients with gastric cancers (including 104 patients who were followed for up to 4090 days) and in 128 patients with colorectal cancer. Cell growth was evaluated by using a colony‐formation assay. For survival analyses, the authors used Kaplan‐Meier plots, the log‐rank test, and Cox proportional regression.</P><P><B>RESULTS:</B></P><P><I>Dkk‐3</I> was silenced or down‐regulated in 12 of 17 gastric cancer cell lines (70.6%) and in 3 of 9 colon cancer cell lines (33.3%). The loss of gene expression was associated with promoter methylation, which could be restored by demethylating agents. Ectopic expression of <I>Dkk‐3</I> suppressed colony formation. Moreover, methylation of <I>Dkk‐3</I> was detected in 117 of 173 primary gastric tumors (67.6%) and in 67 of 128 colorectal tumors (52.3%). The clinical significance and the prognostic value of <I>Dkk‐3</I> methylation also were examined in 104 gastric cancers and in 84 colorectal cancers. Multivariate analysis indicated that <I>Dkk‐3</I> methylation was associated significantly and independently with poor disease survival (relative risk, 2.534; 95% confidence interval, 1.54–4.17; <I>P</I> = .002) in gastric cancer, but not in colorectal cancer. Kaplan‐Meier survival curves revealed that patients who had <I>Dkk‐3</I> methylated gastric cancers had a significantly shorter survival (median, 0.76 years) compared with patients who did not have <I>Dkk‐3</I> methylation (median, 2.68 years; <I>P</I> < .0001; log‐rank test).</P><P><B>CONCLUSIONS:</B></P><P>Epigenetic silencing of the <I>Dkk‐3</I> gene by promoter methylation was a common event in gastric cancer and was associated with a poor outcome in such patients. Cancer 2009. © 2008 American Cancer Society.</P>