Distribution of Glutathione S-Transferase Omega Gene Polymorphism with Different Stages of HBV Infection Including Hepatocellular Carcinoma in the Egyptian Population

Shaban, Nadia Z,Salem, Halima H,Elsadany, Mohamed A,Ali, Bahy A,Hassona, Ehab M,Mogahed, Fayed AK Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.4

Background: Infection with hepatitis B virus (HBV) is a major global public health problem, with a wide spectrum of clinical manifestations. Human cytosolic glutathione-S-transferases (GSTs) include several classes such as alpha (A), mu (M), pi (P), sigma (S), zeta (Z), omega (O) and theta (T). The present study aimed to investigate the role of GST omega genes (GSTO1 and GSTO2) in different groups of patients infected with HBV. Materials and Methods: HBV groups were classified according to clinical history, serological tests and histological analysis into normal carriers (N), acute (A), chronic (CH), cirrhosis (CI) and hepatocellular carcinoma (HCC) cases. The study focused on determination of the genotypes of GST omega genes (GSTO1 and GSTO2) and GST activity and liver function tests. Results: The results showed that GSTO1 (A/A) was decreased in N, A, CH, CI and HCC groups compared to the C-group, while, GSTO1 (C/A) and GSTO1(C/C) genotypes were increased significantly in N, A, CH, CI and HCC groups. GSTO2 (A/A) was decreased in all studied groups as compared to the C-group but GSTO2(A/G) and GSTO2(G/G) genotypes were increased significantly. In addition, GST activities, albumin and TP levels were decreased in all studied groups compared to the C-group, while the activities of transaminases were increased to differing degrees. Conclusions: The results indicate that GSTO genetic polymorphisms may be considered as biomarkers for determining and predicting the progression of HBV infection.

Novel anti-apoptotic mechanism of A20 through targeting ASK1 to suppress TNF-induced JNK activation

Won, M,Park, K A,Byun, H S,Sohn, K-C,Kim, Y-R,Jeon, J,Hong, J H,Park, J,Seok, J H,Kim, J M,Yoon, W-H,Jang, I-S,Shen, H M,Liu, Z G,Hur, G M Macmillan Publishers Limited 2010 CELL DEATH AND DIFFERENTIATION Vol.17 No.12

The zinc-finger protein A20 has crucial physiological functions as a dual inhibitor of nuclear factor-κB (NF-κB) activation and apoptosis in tumor necrosis factor (TNF) receptor 1 signaling pathway. Although the molecular basis for the anti-NF-κB function of A20 has been well elucidated, the anti-apoptotic function of A20 is largely unknown. Here, we report a novel mechanism underlying the anti-apoptotic function of A20: A20 blocks TNF-induced apoptosis through suppression of c-jun N-terminal kinase (JNK) by targeting apoptosis signal-regulating kinase1 (ASK1). First, the ectopic expression of A20 drastically inhibits TNF-induced JNK activation and apoptosis in multiple cell types including those deficient of NF-κB activation. Unexpectedly, the blunting effect of A20 on TNF-induced JNK activation is not mediated by affecting the TNFR1 signaling complex formation. Instead, A20 interacts with ASK1, an important MAPKK kinase in the JNK signaling cascade. More importantly, overexpression of wild-type A20, but not of mutant A20 (ZnF4; C624A, C627A), promotes degradation of the ASK1 through the ubiquitin-proteasome system. Taken together, the results from this study reveal a novel anti-apoptotic mechanism of A20 in TNF signaling pathway: A20 binds to ASK1 and mediates ASK1 degradation, leading to suppression of JNK activation and eventually blockage of apoptosis.

Harmonic decomposition of two particle angular correlations in Pb-Pb collisions at s_NN=2.76 TeV

ALICE Collaboration,Aamodt, K.,Abelev, B.,Abrahantes Quintana, A.,Adamova, D.,Adare, A.M.,Aggarwal, M.M.,Aglieri Rinella, G.,Agocs, A.G.,Agostinelli, A.,Aguilar Salazar, S.,Ahammed, Z.,Ahmad, N.,Ahmad North-Holland Pub. Co 2012 Physics letters: B Vol.708 No.3

Angular correlations between unidentified charged trigger (t) and associated (a) particles are measured by the ALICE experiment in Pb-Pb collisions at s<SUB>NN</SUB>=2.76 TeV for transverse momenta 0.25<p<SUB>T</SUB><SUP>t,a</SUP><15 GeV/c, where p<SUB>T</SUB><SUP>t</SUP>>p<SUB>T</SUB><SUP>a</SUP>. The shapes of the pair correlation distributions are studied in a variety of collision centrality classes between 0 and 50% of the total hadronic cross section for particles in the pseudorapidity interval |η|<1.0. Distributions in relative azimuth Δφ=φ<SUP>t</SUP>-φ<SUP>a</SUP> are analyzed for |Δη|=|η<SUP>t</SUP>-η<SUP>a</SUP>|>0.8, and are referred to as ''long-range correlations''. Fourier components V<SUB>nΔ</SUB>≤cos(nΔφ)> are extracted from the long-range azimuthal correlation functions. If particle pairs are correlated to one another through their individual correlation to a common symmetry plane, then the pair anisotropy V<SUB>nΔ</SUB>(p<SUB>T</SUB><SUP>t</SUP>,p<SUB>T</SUB><SUP>a</SUP>) is fully described in terms of single-particle anisotropies v<SUB>n</SUB>(p<SUB>T</SUB>) as V<SUB>nΔ</SUB>(p<SUB>T</SUB><SUP>t</SUP>,p<SUB>T</SUB><SUP>a</SUP>)=v<SUB>n</SUB>(p<SUB>T</SUB><SUP>t</SUP>)v<SUB>n</SUB>(p<SUB>T</SUB><SUP>a</SUP>). This expectation is tested for 1≤n≤5 by applying a global fit of all V<SUB>nΔ</SUB>(p<SUB>T</SUB><SUP>t</SUP>,p<SUB>T</SUB><SUP>a</SUP>) to obtain the best values v<SUB>n</SUB>{GF}(p<SUB>T</SUB>). It is found that for 2≤n≤5, the fit agrees well with data up to p<SUB>T</SUB><SUP>a</SUP>~3-4 GeV/c, with a trend of increasing deviation as p<SUB>T</SUB><SUP>t</SUP> and p<SUB>T</SUB><SUP>a</SUP> are increased or as collisions become more peripheral. This suggests that no pair correlation harmonic can be described over the full 0.25<p<SUB>T</SUB><15 GeV/c range using a single v<SUB>n</SUB>(p<SUB>T</SUB>) curve; such a description is however approximately possible for 2≤n≤5 when p<SUB>T</SUB><SUP>a</SUP><4 GeV/c. For the n=1 harmonic, however, a single v<SUB>1</SUB>(p<SUB>T</SUB>) curve is not obtained even within the reduced range p<SUB>T</SUB><SUP>a</SUP><4 GeV/c.

Modeling of transient and steady-state dark current in amorphous silicon p–i–n photodiodes

S.A. Mahmood,M.Z. Kabir 한국물리학회 2009 Current Applied Physics Vol.9 No.6

A theoretical model for describing the bias-dependent transient and steady-state behavior of dark current in hydrogenated amorphous silicon (a-Si:H) p–i–n photodiode has been developed. An analytical expression for the bias-dependent steady-state thermal generation current is derived by solving the continuity equations for both electrons and holes. The model for describing transient dark current in a-Si:H p–i–n photodiode is developed by considering the depletion of electrons from the i-layer and carrier injection through p–i interface. For photodiodes that have very good junction properties, the high initial dark current decreases with time monotonously and reaches a plateau. However, in case of poor junctions, the injection current can be the dominating mechanism for transient leakage current at relatively high biases, the dark current decays initially and then rises to a steady-state value. The proposed physics-based dark current model is compared with published experimental results on several photodiodes. The comparison of the model with the experimental data allows an estimate of active dopant concentration in the p-layer and the defect density in the midgap of i-layer. A theoretical model for describing the bias-dependent transient and steady-state behavior of dark current in hydrogenated amorphous silicon (a-Si:H) p–i–n photodiode has been developed. An analytical expression for the bias-dependent steady-state thermal generation current is derived by solving the continuity equations for both electrons and holes. The model for describing transient dark current in a-Si:H p–i–n photodiode is developed by considering the depletion of electrons from the i-layer and carrier injection through p–i interface. For photodiodes that have very good junction properties, the high initial dark current decreases with time monotonously and reaches a plateau. However, in case of poor junctions, the injection current can be the dominating mechanism for transient leakage current at relatively high biases, the dark current decays initially and then rises to a steady-state value. The proposed physics-based dark current model is compared with published experimental results on several photodiodes. The comparison of the model with the experimental data allows an estimate of active dopant concentration in the p-layer and the defect density in the midgap of i-layer.

Evaluation of Hardness and Fracture Toughness in a Porcelain Stoneware with Pseudoboehmite Additions

O. Aguilar-García,S. Bribiesca-Vazquez,J. Zárate-Medina 한양대학교 세라믹연구소 2009 Journal of Ceramic Processing Research Vol.10 No.1

The effect of pseudoboehmite additions to conventional stoneware porcelain is investigated. Green compacts were formed by slip casting of stabilized aqueous suspensions and then sintering at 1,150℃, 1,200℃ and 1,250℃. The phase evolution was followed by XRD, the densification degree was calculated from densities and the microstructures were studied by SEM. Hardness, H and fracture toughness, KIC were measured by Vicker’s indentation. When vitrification occurs the presence of the pseudoboehmite leads to a extra mullitization, which has two consequences: a volume expansion resulting in a high porosity and a decrease of the amount of liquid which causes problems with the densification, by these facts the pseudoboehmite particles decrease the fracture toughness of the bodies. The effect of pseudoboehmite additions to conventional stoneware porcelain is investigated. Green compacts were formed by slip casting of stabilized aqueous suspensions and then sintering at 1,150℃, 1,200℃ and 1,250℃. The phase evolution was followed by XRD, the densification degree was calculated from densities and the microstructures were studied by SEM. Hardness, H and fracture toughness, KIC were measured by Vicker’s indentation. When vitrification occurs the presence of the pseudoboehmite leads to a extra mullitization, which has two consequences: a volume expansion resulting in a high porosity and a decrease of the amount of liquid which causes problems with the densification, by these facts the pseudoboehmite particles decrease the fracture toughness of the bodies.

Functional roles of mannose-binding protein in the adhesion, cytotoxicity and phagocytosis of Acanthamoeba castellanii

Kim, J.H.,Matin, A.,Shin, H.J.,Park, H.,Yoo, K.T.,Yuan, X.Z.,Kim, K.S.,Jung, S.Y. Academic Press 2012 Experimental parasitology Vol.132 No.2

Acanthamoeba castellanii is a single-celled protozoan that is widely distributed in the environment and is a well-known of causing human keratitis, a vision-threatening infection. In this study, an ethyl methane sulfonate (EMS) and a selection of saccharide were applied to A. castellanii by chemical mutagenesis. To understand the functional roles of a mannose-binding protein (MBP). A. castellanii were treated with methyl-alpha-d-mannopyranoside abbreviated Man, with and without the EMS pre-treatment, and their adhesion and cytotoxicity were analyzed, using a human brain microvascular endothelial cell (HBMEC) as the target cell. Both EMS and Man mutants exhibited significantly decreased levels of MBP expression and cytotoxicity to HBMEC, but showed similar levels of binding to HBMEC, as compared with the wild type. Of interest was that the exogenous mannose inhibited amoebae (i.e., Man mutant) binding to the HBMEC by <20%. Only the mutant Man exhibited a significant decrease in bacterial uptake, as compared to the wild type, 0.020 vs 0.032 (p<0.05) and proteolytic activity. The results showed that MBP should be clearly provided as the pathogenic target candidate, to further target-based therapy, but EMS mutation should not be associated with initial adhesion and phagocytosis of A. castellanii.

Fatigue crack effect on magnetic flux leakage for A283 grade C steel

M.I.M. Ahmad,A. Arifin,S. ABDULLAH,W.Z.W. Jusoh,S.S.K. Singh 국제구조공학회 2015 Steel and Composite Structures, An International J Vol.19 No.6

This paper presents the characterization of fatigue crack in the A283 Grade C steel using the MMM method by identifying the effects of magnetic flux leakage towards the crack growth rate, da/dN, and crack length.The previous and current research on the relation between MMM parameters and fatigue crack effect is still unclear and requires specific analysis to validate that. This method is considered to be a passive magnetic method among other Non-Destructive Testing (NDT) methods. The tension-tension fatigue test was conducted with a testing frequency of 10 Hz with 4 kN loaded, meanwhile the MMM response signals were captured using a MMM instrument. A correlation between the crack growth rate and magnetic flux leakage produces a sigmoid shape curve with a constant values which present the gradient, m value is in the ranges of 1.4357 to 4.0506, and the y-intercept, log C in the ranges of 4×10<SUP>-7</SUP> to 0.0303. Moreover, a linear relation was obtained between the crack length and magnetic flux leakage which present the R-Squared values is at 0.830 to 0.978. Therefore, MMM method has their own capability to investigate and characterize the fatigue crack effects as a main source of fracture mechanism for ferrous-based materials.

Genome-wide identification and functional prediction of silicon (Si) transporters in poplar (Populus trichocarpa)

Hassan Md Mahmudul,Martin Samir,Feng Kai,Yates Timothy B.,Yuan Guoliang,Martin Madhavi Z.,Martin Stanton,Muchero Wellington,Griffiths Natalie A.,Weston David J.,Yang Xiaohan 한국식물생명공학회 2023 Plant biotechnology reports Vol.17 No.2

Silicon (Si) enhances plant tolerance to various biotic and abiotic stressors such as salinity, drought, and heat. In addition, Si can be biomineralized within plants to form organic carbon-containing phytoliths that can have ecosystem-level consequences by contributing to long-term carbon sequestration. Si is taken up and transported in plants via different transporter proteins such as influx transporters (e.g., Lsi1, Lsi6) and efflux transporters (e.g., Lsi2). Additionally, the imported Si can be deposited in plant leaves via silicification process using the Siliplant 1 (e.g., Slp1) protein. Functional homologs of these proteins have been reported in different food crops. Here, we performed a genome-wide analysis to identify different Si transporters and Slp1 homologs in the bioenergy crop poplar (Populus trichocarpa Torr. and A. Gray ex W. Hook). We identified one channel-type Si influx transporter (PtLsi1; Potri.017G083300), one Si efflux transporter (PtLsi2; Potri.012G144000) and two proteins like Slp1 (PtSlp1a; Potri.004G168600 and PtSlp1b; Potri.009G129900) in the P. trichocarpa genome. We found a unique sequence (KPKPPVFKPPPVPI) in PtSlp1a which is repeated six times. Repeated presence of this sequence in PtSlp1a indicates that this protein might be important for silicification processes in P. trichocarpa. The mutation profiles of different Si transporters in a P. trichocarpa genome-wide association study population identified significant and impactful mutations in Potri.004G168600 and Potri.009G129900. Using a publically accessible database (http://bar.utoronto.ca/eplant_poplar/), digital expression analysis of the putative Si transporters in P. trichocarpa found low to moderate expression in the anticipated tissues, such as roots and leaves. Subcellular localization analysis found that PtLsi1/PtLsi2 are localized in the plasma membrane, whereas PtSlp1a/PtSlp1b are found in the extracellular spaces. Protein–Protein interaction analysis of PtLsi1/PtLsi2 identified Delta-1-pyrroline-5-carboxylate synthase (P5CS) as one of the main interacting partners of PtLsi2, which plays a key role in proline biosynthesis. Proline is a well-known participant in biotic and abiotic stress tolerance in plants. These findings will reinforce future efforts to modify Si accumulation for enhancing plant stress tolerance and carbon sequestration in poplar.

Strength of Thixoformed A319 Alloy at Elevated Temperature

A. M. Aziz,M. Z. Omar,Z. Sajuri 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.7

When alloys are exposed to elevated temperatures they experience a decrement in their mechanical properties that leadsto material failure. However, the use of thixoforming, an alternative metal processing method, could enhance mechanicalproperties by minimising the defects that exist in as-received alloys. Therefore, this study aimed to determine the tensilestrength of thixoformed A319 under elevated temperatures by taking into account its intended use in vehicle cylinder headcomponents. Thixoformed A319 was compared with as-received alloy manufactured by permanent mould casting. Thecooling slope method was used to prepare the feedstock for thixoforming. The feedstock was reheated by induction heatinguntil it reached 574 °C and was then formed in a mould. Afterwards, the as-received and thixoformed samples underwentT6 heat treatment. The resulting samples were characterised by using optical microscopy, scanning electron microscopyequipped with energy dispersive X-ray, X-ray difraction analysis and a tensile test. Elevated temperature tensile tests wereperformed at 250 °C, in line with the temperature condition experienced by cylinder head components during operation. The ultimate tensile strength of the thixoformed samples was 30% higher than that of the as-received samples under elevatedtemperatures. Also, the analyses of the fracture surfaces showed that porosity, intermetallic compounds and impurities wereamongst the failure factors for both alloys.

A tale of two GRB-SNe at a common redshift of z=0.54

Cano, Z.,Bersier, D.,Guidorzi, C.,Margutti, R.,Svensson, K. M.,Kobayashi, S.,Melandri, A.,Wiersema, K.,Pozanenko, A.,van der Horst, A. J. Blackwell Publishing Ltd 2011 Monthly notices of the Royal Astronomical Society Vol.413 No.1