Eco-friendly Chitosan Condensation Adduct Resins for Removal of Toxic Silver Ions from Aqueous Medium

Hadeel G. El-Shorbagy,Salah M. El-kousy,Khalid Z. Elwakeel,M.A. Abd El-Ghaffar 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.100 No.-

A simple and economical method for modifying chitosan based on non-catalytic direct condensationreaction between chitosan and phenolic acids “Gallic and Caffeic acids” has been developed to producecondensation adduct resins RI and RII. The resins structure and morphology were confirmed by physicaland chemical tools such as FTIR, SEM, EDX, XRD elemental analysis, TGA, water regain, dissociation inacidic medium, and point of zero charge. The new resins were evaluated as silver ions adsorbents. Factorsaffecting adsorption, as well as kinetics, equilibrium, and thermal properties of adsorption, were studiedusing conventional equations. The new resins showed more efficient removal of toxic silver ions from theaqueous medium than parent chitosan polymer. The maximum adsorption capacity amounted to 67.5,300, and 278 mg/g with removal efficiency reaching 22.5%, 100%, and 92.66% for chitosan, RI, and RII;respectively at pH 6.5 and initial silver concentration 300 mg/L. The new resins showed spontaneouschemisorption toward silver ions with exothermic nature for RI, and endothermic nature for RII. The newcondensation adduct resins showed good re-use ability reaching 83% and 67% for RI and RII; respectively,by using 0.01 M nitric acid solution.

Designing and Implementing of Dynamic Technique for Detecting Learning Style Using Literature Based Approach

Hadeel Ateia,Thair Hamtini 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.6

This paper is a part of ongoing research that tries to approve our hypothesis about adaptive personalization in web-based learning systems; we are debating that building online learning environments with the ability to detect learners learning style dynamically by observing their behaviour and then presenting learning material based on the detected learning style is more effective than using ILS questionnaire. In an earlier work, we provided a dynamic technique that identifies learners VAK learning styles according to their behaviour in the learning environment influenced by literature approach, in this paper we have modified our technique and re-proposed it. First, we connected behavioural patterns (time, visits and answer patterns) to the features (contents, outlines, group forums, examples, case studies, exercises and assessments), then we defined the effect each VAK learning style will have on each pattern. Next, we described three general rules and three algorithms that should detect the learning style. Now we are in the process of building two online learning environments to test and confirm the differences between dynamic learning style detection _ based on our technique _ and the traditional ILS questionnaire environments; we choose a course called ‘Computer Skills for medicine faculty students’, which is provided from the faculty of Information Technology at the University of Jordan; the results of the planed experiment will be saved and analysed using SPSS.

Drosophila melanogaster as a Model for Studying Aspergillus fumigatus

( Hadeel Saeed Al-maliki ),( Suceti Martinez ),( Patrick Piszczatowski ),( Joan W. Bennett ) 한국균학회 2017 Mycobiology Vol.45 No.4

Drosophila melanogaster is a useful model organism that offers essential insights into developmental and cellular processes shared with humans, which has been adapted for large scale analysis of medically important microbes and to test the toxicity of heavy metals, industrial solvents and other poisonous substances. We here give a brief review of the use of the Drosophila model in medical mycology, discuss the volatile organic compounds (VOCs) produced by the opportunistic human pathogen, Aspergillus fumigatus, and give a brief summary of what is known about the toxicity of some common fungal VOCs. Further, we discuss the use of VOC detection as an indirect indicator of fungal growth, including for early diagnosis of aspergillosis. Finally, we hypothesize that D. melanogaster has promise for investigating the role of VOCs synthesized by A. fumigatus as possible virulence factors.

Improvement of Bacilysin Production in Bacillus subtilis by CRISPR/Cas9-Mediated Editing of the 5’-Untranslated Region of the bac Operon

( Hadeel Waleed Abdulmalek ),( Ayten Yazgan-karata ) 한국미생물생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.3

Bacilysin is a dipeptide antibiotic composed of L-alanine and L-anticapsin produced by certain strains of Bacillus subtilis. Bacilysin is gaining increasing attention in industrial agriculture and pharmaceutical industries due to its potent antagonistic effects on various bacterial, fungal, and algal pathogens. However, its use in industrial applications is hindered by its low production in the native producer. The biosynthesis of bacilysin is mainly based on the bacABCDEF operon. Examination of the sequence surrounding the upstream of the bac operon did not reveal a clear, strong ribosome binding site (RBS). Therefore, in this study, we aimed to investigate the impact of RBS as a potential route to improve bacilysin production. For this, the 5’ untranslated region (5’UTR) of the bac operon was edited using the CRISPR/Cas9 approach by introducing a strong ribosome binding sequence carrying the canonical Shine-Dalgarno sequence (TAAGGAGG) with an 8 nt spacing from the AUG start codon. Strong RBS substitution resulted in a 2.87-fold increase in bacilysin production without affecting growth. Strong RBS substitution also improved the mRNA stability of the bac operon. All these data revealed that extensive RBS engineering is a promising key option for enhancing bacilysin production in its native producers.

Involvement of α_1B-adrenoceptors and Rho kinase in contractions of rat aorta and mouse spleen

Hadeel A. Alsufyani,James R. Docherty The Korean Society of Pharmacology 2023 The Korean Journal of Physiology & Pharmacology Vol.27 No.4

α₁-adrenoceptors link via the G-protein Gq/G₁₁ to both Ca²⁺ entry and release from stores, but may also activate Rho kinase, which causes calcium sensitization. This study aimed to identify the subtype(s) of α₁-adrenoceptor involved in Rho kinase-mediated responses in both rat aorta and mouse spleen, tissues in which contractions involve multiple subtypes of α₁-adrenoceptor. Tissues were contracted with cumulative concentrations of noradrenaline (NA) in 0.5 log unit increments, before and in the presence of an antagonist or vehicle. Contractions produced by NA in rat aorta are entirely α₁-adrenoceptor mediated as they are competitively blocked by prazosin. The α_1A-adrenoceptor antagonist RS100329 had low potency in rat aorta. The α_1D-adrenoceptor antagonist BMY7378 antagonized contractions in rat aorta in a biphasic manner: low concentrations blocking α_1D-adrenoceptors and high concentrations blocking α_1B-adrenoceptors. The Rho kinase inhibitor fasudil (10 µM) significantly reduced aortic contractions in terms of maximum response, suggesting inhibition of α_1B-adrenoceptor mediated responses. In the mouse spleen, a tissue in which all 3 subtypes of α₁-adrenoceptor are involved in contractions to NA, fasudil (3 µM) significantly reduced both early and late components to the NA contraction, the early component involving α_1B- and α_1D-adrenoceptors, and the late component involving α_1B- and α_1A-adrenoceptors. This suggests that fasudil inhibits α_1B-adrenoceptor mediated responses. It is concluded that α_1D- and α_1B-adrenoceptors interact in rat aorta and α_1D-, α_1A- and α_1B-adrenoceptors interact in the mouse spleen to produce contractions and these interactions suggest that one of the receptors preferentially activates Rho kinase, most likely the α_1B-adrenoceptor.

Roles for α1-adrenoceptors during contractions by electrical field stimulation in mouse vas deferens

Hadeel A. Alsufyani,James R. Docherty 대한생리학회-대한약리학회 2021 The Korean Journal of Physiology & Pharmacology Vol.25 No.6

We have investigated the relative roles of α1-adrenoceptors and purinoceptors in contractions to low and high frequency stimulation of the mouse vas deferens, in terms of the time course of responses. In separate experiments, isometric contractile responses were obtained to 10 pulses at 1 Hz and 40 pulses at 10 Hz. Responses to 1 Hz stimulation consisted of a series of discrete peaks. The α1A-adrenoceptor antagonist RS100329 (10-9M-10-7M) significantly reduced the response to the first pulse, the α1D-adrenoceptor antagonist BMY7378 (10-7M-10-6M) significantly reduced the response to the first two pulses, and the non-selective α1- adrenoceptor antagonist prazosin (10-8M) reduced the response to the first 4 pulses at 1 Hz. Responses to 10 Hz stimulation consisted of an early peak response and a maintained plateau response. RS100329 significantly reduced the peak response but did not significantly affect the plateau response. Prazosin, significantly reduced both the peak and plateau responses. The α1A-adrenoceptor antagonist RS17053 in high concentrations reduced mainly the plateau response leaving a clear early peak response. The plateau response of contraction was almost abolished by the purinoceptor antagonist suramin. These results suggest that there is a relatively minor early α1D-adrenoceptor and a larger early α1A-adrenoceptor component to stimulationevoked contractions of mouse vas deferens, but the major α1-adrenoceptor component is revealed by prazosin to be α1B-adrenoceptor mediated. α1B-Adrenoceptor activation probably facilitates contractions mediated by other α1-adrenoceptors and by purinoceptors. These results suggest that combined non-selective α1-adrenoceptor blockade, particularly α1B-adrenoceptor blockade, in addition to P2X1-purinoceptor blockade is useful in reducing male fertility

Color stability of 3D-printed denture resins: effect of aging, mechanical brushing and immersion in staining medium

Afnan Fouzan Alfouzan,Hadeel Minife Alotiabi,Nawaf Labban,Hanan Nejer Al-Otaibi,Sara Mohammad Al Taweel,Huda Ahmed AlShehri 대한치과보철학회 2021 The Journal of Advanced Prosthodontics Vol.13 No.3

Purpose. This in-vitro study evaluated and compared the color stability of 3D-printed and conventional heat-polymerized acrylic resins following aging, mechanical brushing, and immersion in staining medium. Materials and methods. Forty disc-shaped specimens (10 mm in diameter and 3 mm thick) were prepared from two 3D-printed [DentaBASE (DB) and Denture 3D+ (D3D)] and one conventional polymethylmethacrylate (PMMA) denture materials. The specimens were thermo-cycled, subjected to mechanical brushing, and were immersed in either coffee, lemon juice, coke, or artificial saliva (AS) to simulate one and two years of oral use. Color measurements of the specimens were recorded by a spectrophotometer at baseline (T0), and after one (T1) and two years (T2) of simulation. The color changes (ΔE) were determined and also quantified according to the National Bureau of Standards (NBS) units. Descriptive statistics, followed by factorial ANOVA and Bonferroni post-hoc test (α=.05), were applied for data analysis. Results. The independent factors, namely material, staining medium, and immersion time, and interaction among these factors significantly influenced ΔE (P <.009). Irrespective of the materials, treatments, and time, the highest and the lowest mean ΔEs were observed for PMMA in lemon juice (4.58 ± 1.30) and DB in AS (0.41 ± 0.18), respectively. Regarding the material type, PMMA demonstrated the highest mean ΔE (2.31 ± 1.37), followed by D3D (1.67 ± 0.66), and DB (0.85 ± 0.52), and the difference in ΔE between the materials were statistically significant (P <.001). All the specimens demonstrated a decreased color changes at T2 compared to T1, and this difference in mean ΔE was statistically significant (P <.001). Conclusion. The color changes of 3D-printed denture resins were low compared to conventional heat polymerized PMMA. All the tested materials, irrespective of the staining medium used, demonstrated a significant decrease in ΔE values over time.

Supported and Unleashed - The Impact of Work Environment on the Creative Performance of Knowledge Workers: An Empirical Study in Saudi Arabia

FALLATAH, Mahmoud,SINDI, Hadeel Korea Distribution Science Association 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.10

Organizations pursue innovation to improve performance and gain competitive advantage, and knowledge workers represent an integral part of creating knowledge and helping organizations in their innovation efforts. The current paper seeks to examine the impact of the work environment on knowledge workers' creativity. Building on The Investment Theory of Creativity, The Componential Theory of Creativity, the Job Demand-Resource model, and the Resource Based View, we develop and test a model suggesting a relationship between work environment-social support, sufficient resources, organizational freedom, and organizational regulations-and the quantity and quality of the creative performance of knowledge workers. Using a sample of 167 engineers in Saudi Arabia, an emerging but wealthy country with huge innovation inspirations, the results of our Ordinary Least Squares (OLS) regression analysis indicate that all four elements of the work environment included in our study positively impact the quantity and quality of knowledge workers' creative performance. Our paper provides important contributions to the literature on the work environment, creativity, and knowledge management, with an emphasis on creativity in developing countries. Our study highlights the importance of creating a supportive and encouraging work environment for knowledge workers to foster their creativity. The study offers several theoretical and managerial implications, along with suggestions for future research.

Smudge cell percentage as a surrogate marker for ZAP-70 expression in patients with chronic lymphocytic leukemia

Waiel Al-Kahiry,Hadeel Said Tawfik,Homam Sharshira,Amal Ghanem,Maha El-Gammal,Irene Lewis Mikhael 대한혈액학회 2018 Blood Research Vol.53 No.3

Background This study aimed to evaluate the prognostic value of smudge cell percentage as a surrogate marker for zeta-chain-associated protein kinase 70 (ZAP-70) expression in chronic lym-phocytic leukemia (CLL) patients. Methods Sixty three newly diagnosed CLL patients were investigated at the Hematology Department of the Medical Research Institute of Alexandria University with complete blood count, lactate dehydrogenase, 2 microglobulin levels, ZAP-70 expression, and es-timation of the percentage of smudge cells. Results The percentage of smudge cells ranged from 2 to 58% with a mean of 24.03±13.98%.Higher percentages of smudge cells (>30%) were statistically significantly associated with markers of better prognosis (negative ZAP-70, early-stage disease according to the Binet and Rai staging systems, as well as low and intermediate risk CLL prognostic index). The percentage of smudge cells showed significantly negative correlation with the ZAP-70 expression and higher area under the curve for prediction of ZAP-70 positivity with better survival for 36 months in patients with >30% smudge cells. Conclusion The percentage of smudge cells at presentation of newly diagnosed CLL patients could be used as a surrogate marker for ZAP-70 expression and an additional prognostic marker for disease progression.

Smudge cell percentage as a surrogate marker for ZAP-70 expression in patients with chronic lymphocytic leukemia

Waiel Al-Kahiry,Hadeel Said Tawfik,Homam Sharshira,Amal Ghanem,Maha El-Gammal,Irene Lewis Mikhael 대한혈액학회 2018 Blood Research Vol.53 No.3

Background This study aimed to evaluate the prognostic value of smudge cell percentage as a surrogate marker for zeta-chain-associated protein kinase 70 (ZAP-70) expression in chronic lym-phocytic leukemia (CLL) patients. Methods Sixty three newly diagnosed CLL patients were investigated at the Hematology Department of the Medical Research Institute of Alexandria University with complete blood count, lactate dehydrogenase, 2 microglobulin levels, ZAP-70 expression, and es-timation of the percentage of smudge cells. Results The percentage of smudge cells ranged from 2 to 58% with a mean of 24.03±13.98%.Higher percentages of smudge cells (>30%) were statistically significantly associated with markers of better prognosis (negative ZAP-70, early-stage disease according to the Binet and Rai staging systems, as well as low and intermediate risk CLL prognostic index). The percentage of smudge cells showed significantly negative correlation with the ZAP-70 expression and higher area under the curve for prediction of ZAP-70 positivity with better survival for 36 months in patients with >30% smudge cells. Conclusion The percentage of smudge cells at presentation of newly diagnosed CLL patients could be used as a surrogate marker for ZAP-70 expression and an additional prognostic marker for disease progression.