Simulation Guided Microfluidic Design for Multitarget Separation Using Dielectrophoretic Principle

Mohamed Zackria Ansar B.I.,Vineet Tirth,Caffiyar Mohamed Yousuff,Neeraj Kumar Shukla,Saiful Islam,Kashif Irshad,Mohammed Aarif K.O. 한국바이오칩학회 2020 BioChip Journal Vol.14 No.4

Microfluidic technologies have emerged as a potential tool for point of care - diagnostics and therapeutics applications. Isolation of multi-targets (Cancer cells along with platelets, red blood cells (RBCs), white blood cells (WBCs), and antigen-presenting cells (APCs)) simultaneously is of great interest in drug discovery and medical diagnosis. By utilizing dielectrophoresis (DEP) effect inside the micro channel, several attempts were made to separate binary mixtures by precisely controlling and manipulating the motion of the particles. However, all of these methods limit its applicability for multi-target particle separation in a single run. In this paper, we attempt to develop a simulation model with novel electrode arrangements to isolate multiple particles using negative DEP. Our proposed model establishes criteria for separating micron- sized particle mixtures (3μm, 7μm, 15μm, 20μm, 25μm) with various electrode shapes, electrode potentials, inlet velocities, and channel widths. The device efficiency was evaluated for a triangular electrode, square-shaped electrode, and rectangular electrode under various practical design constraints. Our study demonstrates an optimum solution for effective separation of particle mixtures using triangular electrode arrangements (utilizing less voltage) and a wider channel of 300μm width that eventually avoid channel clogging issues due to cells inside main channel and collection channels. While evaluating the separation efficiency of the proposed design, we observe that platelets, RBCs, WBCs, APCs, and CTCs experienced distinct DEP force on each, allowing them to collect in different collection outlets without any crossmixing. Hence our proposed design allows flexibility to the researchers working on DEP by using a wider channel with triangular electrode arrangements enabling them to fabricate the device under resourcelimited constraints

Influence of thickness and crystalline structure on thermal and optical properties of ZnO thin films

K.I. Mohammed,F.M. Jasim,M.I. Azawe 한국물리학회 2014 Current Applied Physics Vol.14 No.9

Measurements of the temperature dependence of refractive index of ZnO thin films and thermal diffusivity using photothermal deflection technique are presented. Thin film thickness and surface homogeneity were found to be the effective parameters on optical and thermal properties of the thin films. High refractive index gradient with temperature was found for films of a nonuniform distribution and gathered in clusters, and a high predicted value for thermal diffusivity. Optical properties of the thin films revealed that films with disorder in the deposition and gathered clusters showed poor transmittance in visible region with a pronounced peak in the near IR, and also a reduction in the band gap. A detailed parametric analysis using analytical solution of one-dimensional heat equation had been performed. A discontinuity in the temperature elevation at the ZnO-glass interface was found.

Increased Hypermethylation of Glutathione S-Transferase P1, DNA-Binding Protein Inhibitor, Death Associated Protein Kinase and Paired Box Protein-5 Genes in Triple-Negative Breast Cancer Saudi Females

Hafez, Mohamed M.,Al-Shabanah, Othman A.,Al-Rejaie, Salim S.,Al-Harbi, Naif O.,Hassan, Zeinab K.,Alsheikh, Abdulmalik,Theyab, Abdurrahman I. Al,Aldelemy, Meshan L.,Sayed-Ahmed, Mohamed M. Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.2

Triple negative breast cancer (TNBC) is an aggressive subtype of breast cancer (BC) with higher metastatic rate and both local and systemic recurrence compared to non-TNBC. The generation of reactive oxygen species (ROS) secondary to oxidative stress is associated with DNA damage, chromosomal degradation and alterations of both hypermethylation and hypomethylation of DNA. This study concerns differential methylation of promoter regions in specific groups of genes in TNBC and non-TNBC Saudi females in an effort to understand whether epigenetic events might be involved in breast carcinogenesis, and whether they might be used as markers for Saudi BCs. Methylation of glutathione S-transferase P1 (GSTP1), T-cadherin (CDH13), Paired box protein 5 (PAX5), death associated protein kinase (DAPK), twist-related protein (TWIST), DNA-binding protein inhibitor (ID4), High In Normal-1 (HIN-1), cyclin-dependent kinase inhibitor 2A (p16), cyclin D2 and retinoic acid receptor-${\beta}$ ($RAR{\beta}1$) genes was analyzed by methylation specific polymerase chain reaction (MSP) in 200 archival formalin-fixed paraffin embedded BC tissues divided into 3 groups; benign breast tissues (20), TNBC (80) and non-TNBC (100). The relationships between methylation status, and clinical and pathological characteristics of patients and tumors were assessed. Higher frequencies of GSTP1, ID4, TWIST, DAPK, PAX5 and HIN-1 hypermethylation were found in TNBC than in non-TNBC. Hypermethylation of GSTP1, CDH13, ID4, DAPK, HIN-1 and PAX5 increased with tumor grade increasing. Other statistically significant correlations were identified with studied genes. Data from this study suggest that increased hypermethylation of GSTP1, ID4, TWIST, DAPK, PAX5 and HIN-1 genes in TNBC than in non-TNBC can act as useful biomarker for BCs in the Saudi population. The higher frequency of specific hypermethylated genes paralleling tumor grade, size and lymph node involvement suggests contributions to breast cancer initiation and progression.

Erythrocyte-mediated Delivery of Pravastatin: In Vitro Study of Effect of Hypotonic Lysis on Biochemical Parameters and Loading Efficiency

Gamaleldin I. Harisa,Mohamed F. Ibrahim,Fars K. Alanazi 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.8

Exposure of erythrocytes to hypotonic lysis creates pores in the cell membrane, through which pravastatin can enter and become trapped, after resealing them with a suitable buffer. We investigated the effects of tonicity, incubation time and drug concentration on drug loading into erythrocytes. Furthermore, we investigate the effects of pravastatin on erythrocyte oxidative stress markers and osmotic fragility behavior. Encapsulation was achieved using buffer solutions of different tonicities (0.5, 0.6 and 0.7% NaCl) and different drug concentrations (2, 4, 8 and 10 mg/mL) for a range of incubation times (15, 30, 60 and 120 min). The results demonstrated that controlled hypotonic lysis could entrap pravastatin in human erythrocytes, with acceptable loading parameters. The highest loading (34%) was achieved at 0.6% NaCl and 10 mg/mL pravastatin for 60 min incubation. At this pravastatin concentration, oxidative stress markers were similar to those seen in controls, and fragility and hematological parameters were unaffected in drug-loaded erythrocytes. These results indicate that the loading process and pravastatin concentration had no deleterious effects on the structure of pravastatinloaded erythrocytes, suggesting that they may therefore have a similar life span to normal cells. Pravastatin-loaded erythrocytes may thus provide an effective extended-release-delivery system for pravastatin.

Preparation and characterization of wollastonite/titanium oxide nanofiber bioceramic composite as a future implant material

Aly, I.H.M.,Abed Alrahim Mohammed, L.,Al-Meer, S.,Elsaid, K.,Barakat, N.A.M. Ceramurgica ; Elsevier Science Ltd 2016 CERAMICS INTERNATIONAL Vol.42 No.10

In this study, novel composites consisting of electrospun titanium dioxide (TiO<SUB>2</SUB>) nanofibers incorporated into high-purity wollastonite glass ceramics were prepared as materials for use in hard tissue engineering applications. These materials were characterized and investigated by means of physical, mechanical and in vitro studies. The proposed composite showed greater densification and better mechanical characteristics compared to pure wollastonite. The influence of densification temperature and TiO<SUB>2</SUB> content was investigated. Typically, TiO<SUB>2</SUB>/wollastonite composites having 0, 10, 20 and 30wt% metal oxide nanofibers were sintered at 900, 1100 and 1250<SUP>o</SUP>C. The results indicated that increasing TiO<SUB>2</SUB> nanofibers content leads to increase the bulk density, compressive strength and microhardness with negligible, high and moderate influence for the densification temperature, respectively. While porosity and water adsorption capacity decreased with increasing the metal oxide nanofibers with a considerable impact for the sintering temperature in both properties. Moreover, bone-like apatite formed on the surface of wollastonite and wollastonite/TiO<SUB>2</SUB> nanofibers soaked in simulated body fluid (SBF). All these results show that the inclusion of TiO<SUB>2</SUB> nanofibers improved the characteristics of wollastonite while preserving its in vitro bioactivity; hence, the proposed composite may be used as a bone substitute in high load bearing sites.

Experimental study of the radiation shielding characteristics of new PbO– Na2O–B2O3–BaO glasses

Sayyed M.I.,Rilwan U.,Mahmoud K.A.,Elsafi Mohamed 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.7

This work synthesized four glass samples with a fixed ratio of PbO to Na2O and a variable ratio of BaO to B2O3. The linear attenuation coefficient (LAC) (μ, cm 1) and additional attenuator parameters were determined experimentally using a semiconductor detector and different gamma sources. The comparison was carried out between the experimental and the XCOM calculated results, with good agreement emerging between the two results. The impacts of the BaO substituting for the B2O3 on fabricated PNBB glasses’ radiation shielding properties were discussed. By increasing the BaO substitution concentration between 10 and 25 mol.%, the LAC μ values (cm 1) increased by 76.60 %, 13.81 %, 12.56 %, and 12.52 % for the respective γ-ray energies of 0.059, 0.662, 1.173, and 1.332 MeV. The μ value reduction with raised gamma energy values increased the values of the calculated half-value thickness (Δ0.5) as a result of the μ and Δ0.5 values’ reverse proportionality. Other shielding parameters such as the lead equivalent thickness (Δeq) and radiation protection efficiency were also determined for the present PNBB glass samples.

Impacts of Selection for Spike Length on Heat Stress Tolerance in Bread Wheat (Triticum aestivum L.)

Asmaa M. Mohamed,Mohamed K. Omara,Mahmoud A. El-Rawy,Mohamed I. Hassan 한국육종학회 2019 Plant Breeding and Biotechnology Vol.7 No.2

Two consecutive cycles of selection were imposed on five F2 populations of bread wheat. The first cycle was a divergent selection for spike length conducted in favorable environment (optimal sowing date) and the response was measured under favorable and heat stress conditions of a late sowing date. Positive responses to selection for longer spikes were obtained under favorable (13.43%) heat stress (8.66%) conditions, whereas the responses for shorter spikes were 2.24 and 5.02% in the two environments, respectively. The realized heritability of spike length was greater under favorable conditions (0.25-0.56) than under heat stress (0.18- 0.41). Concurrent positive responses to selection for longer spikes were obtained in grain yield per spike under favorable (25.35%) and heat stress (13.65%) environments. Selection for greater number of grains per spike imposed on F3 plants selected for spike length under heat stress resulted in significant responses (14.65%). Selection for greater number of grains per spike resulted in correlated responses in grain yield per spike (17.64%). The concurrent positive responses produced in spike length in F4 with selection for number of grains per spike (averaged 9.20%) was almost equal to that produced by the direct selection in F3 (8.66%), indicating that selection advance effected in F3 has been maintained in F4. High F4/F3 regression was obtained for spike length under heat stress (b = 0.85 ± 0.07), indicating high heritability. In conclusion, phenotypic selection for longer spikes under heat stress followed by a cycle of selection for number of grains per spike was capable of improving heat tolerance in wheat.

The radiation shielding competence and imaging spectroscopic based studies of Iron ore region of Kozhikode district, Kerala

S. Arivazhagan,K.A. Naseer,K.A. Mahmoud,S.A. Bassam,P.N. Naseef Mohammed,N.K. Libeesh,A.S. Sachana,M.I. Sayyed,Mohammed S. Alqahtani,E. El Shiekh,Mayeen Uddin Khandaker Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.7

Hyperspectral data and its ability to explore the minerals and their associated rocks have a remarkable application in mineral exploration and lithological characterization. The present study aims to explore the radiation shielding aspects of the iron ore in Kerala with the aid of the Hyperion hyperspectral dataset. The reflectance-spectra obtained from the laboratory conditions as well as from the image show various absorptions. The results from the spectra are validated with geochemical data and GPS points. The Monte Carlo simulation employed to evaluate the radiation shielding ability. Raising the oxygen ions caused a noteworthy decrease in the µ values of the studied rocks which is accompanied by an increase in Δ_0.5 and Δ_eq values. The Δ_0.5 and Δ_eq values increased by factors of approximately 77 % with raising the oxygen ions between 44.32 and 47.57 wt.%. The µ values varies with the oxygen concentrations, where the µ values decreased from 2.531 to 0.925 cm^-1 (at 0.059 MeV), from 0.381to 0.215 cm^-1 (at 0.662 MeV), and from 0.279 to 0.158 cm^-1 (at 1.25 MeV) with raising the oxygen ions from 44.32 to 47.43 wt.%.

Ameliorative Effects of Pomegranate Peel Extract against Dietary-Induced Nonalcoholic Fatty Liver in Rats

Siham N. K. Al-Shaaibi,Mostafa I. Waly,Lyutha Al-Subhi,Mohamed H. Tageldin,Nada M. Al-Balushi,Mohammad S. Rahman 한국식품영양과학회 2016 Preventive Nutrition and Food Science Vol.21 No.1

Non-alcoholic fatty liver disease (NAFLD) is caused by fat accumulation and is associated with oxidative stress. In this study, we investigated the potential protective effect of pomegranate (Punica granatum L.) peel extract (PPE) against oxidative stress in the liver of rats with NAFLD. Sprague-Dawley rats were fed a high fat diet (HFD), 20% corn oil, or palm oil for 8 weeks in the presence or absence of PPE. The control group was fed a basal diet. The progression of NAFLD was evaluated histologically and by measuring liver enzymes (alanine transaminase and aspartate transaminase), serum lipids (triglycerides and total cholesterol), and oxidative stress markers. The HFD feeding increased the body weight and caused NAFLD, liver steatosis, hyperlipidemia, oxidative stress, and elevated liver enzymes. Administration of PPE ameliorated the hepatic morphology, reduced body weight, improved liver enzymes, and inhibited lipogenesis. Furthermore, PPE enhanced the cellular redox status in the liver tissue of rats with NAFLD. Our findings suggest that PPE could improve HFD-induced NAFLD via abolishment of hepatic oxidative damage and hyperlipidemia. PPE might be considered as a potential lead material in the treatment of NAFLD and obesity through the modulation of lipid metabolism.

A comprehensive evaluation of Mg-Ni based alloys radiation shielding features for nuclear protection applications

Sayyed M.I.,Mahmoud K.A.,Mohammed Faras Q.,Kaky Kawa M. 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.5

The current study aims to study the impacts of the substitution of magnesium with nickel concentrations on physical and γ-ray shielding capacity of magnesium alloys. The density of the magnesium alloys under study is varied from 3.677 g/cm3 to 5.652 g/cm3, with raising the nickel content from 26.7 wt% to 54.8 wt% and reducing the magnesium concentration from 72.6 wt% to 44.2 wt%, respectively. Additionally, the examination of the γ-ray shielding capacity using the Monte Carlo simulation code shows that the substitution of magnesium by nickel content in the magnesium alloys was associated with an enhancement in the γ-ray shielding capacity, where the linear attenuation coefficient for the studied alloys was enhanced by 53.22 %, 52.45 %, and 52.52 % at γ-ray energies of 0.662 MeV, 1.252 MeV, and 1.408 MeV, respectively, with raising the nickel concentration from 26.7 wt% to 54.8 wt%. Simultaneously, the half-value thickness for magnesium alloys was reduced from 2.47 cm to 1.62 cm (at gamma ray energy of 0.662 MeV), from 3.39 cm to 2.22 cm (at gamma ray energy of 1.252 MeV), and from 3.60 cm to 2.36 cm (at gamma ray energy of 1.408 MeV), raising the nickel concentration from 26.7 wt % to 54.8 wt%, respectively. The study shows that the substitution of magnesium for nickel greatly enhanced the radiation shielding capacity of the magnesium alloys.