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Synthesis and Characterization of Poly Styrene-Co-Poly 2-Hydroxyethylmethacrylate (HEmA) Copolymer and an Investigation of Free-Radical Copolymerization Propagation Kinetics by Solvent Effects

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Open Journal of Polymer Chemistry 2024年第1期14卷 63-93页

作者： Anaif.m. Alhewaitey Ishrat Khan naif.m. alhawiti Department of Chemistry Clark Atlanta University Atlanta USA Department of Chemistry University of Tabuk Tabuk Saudi Arabia CAHFS University of California Davis Davis California

A series of homo and copolymers of styrene (ST) and 2-hydroxyethyl methacrylate (HEmA) in three different media (bulk, tetrahydrofuran, and benzene) have been investigated by free radical polymerization method. The samples obtained from the synthesis were characterized by Fourier Transform-Infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NmR), atomic force microscopy (AFm), and differential scanning calorimetry (DSC). The results show that the synthesis of the polymers is more feasible under neat conditions rather than solvent directed reaction. moreover, the DSC data shows that the polystyrene obtained is amorphous in nature and therefore displayed only a glass transition signal rather than crystallization and melting peaks. In addition, this study indicates that homolopolymerization of styrene via free radical polymerization tends to be preferable in less polar solvents like THF than in non-polar solvents like benzene. Benzene might destabilize the formation of the reactive radicals leading to the formation of the products. In summary, the homolpolymerization of styrene is more feasible than the homopolymerization 2-hydroxyethyl methacrylate under the experimental setup used. Styrene is more reactive than 2-hydroxyethyl methacrylate than free radical polymerization reaction due in part of the generation of the benzylic radical intermediate which is more stable leading to the formation of products than alkyl radical which are less stable. Furthermore, polymerization of styrene under neat conditions is preferable in solvent-assisted environments. The choice of solvent for the synthesis of these polymers is crucial and therefore the selection of solvent that leads to the formation of a more stable reaction intermediate is more favorable. It is worth noting that the structure of the proposed copolymer consists of a highly polar and hydrophilic monomer, 2-hydroxyethyl methacrylate and a highly non-polar and hydrophobic monome

关键词： 2-Hydroxyethyl methacrylate Polymerization

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Interactions of Aurein with model membranes and Antimalarials

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American Journal of Analytical Chemistry 2024年第2期15卷 72-98页

作者： Anaif.m. Alhewaitey Nsoki Phambu naif.m. alhawiti Department of Chemistry Tennessee State University Nashville USA Department of Chemistry University of Tabuk Tabuk Saudi Arabia CAHFS University of California Davis Davis USA

Aurein is a cationic antimicrobial peptide, rich in phenylalanine residues. Although the peptide has been extensively studied, its mechanism of action is not fully understood and has not been established. This project is focused on studying the interactions of aurein with model biological membranes and antimalarials using Fourier Transform Infrared (FTIR), fluorescence, dynamic light scattering (DLS), atomic force microscopy (AFm), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) techniques. FTIR data revealed conformational changes to the secondary structure of the peptide in the presence of the model membranes. The strongest interactions of aurein were found with DOPC and lipid raft systems. Fluorescence data revealed some differences in the mechanism of interaction between aurein and lipid rafts. Topographical analysis was performed using atomic force microscopy (AFm). AFm images of the peptide with its lipid rafts showed a change in surface roughness suggesting a different mechanism of interaction. DLS data in agreement with FTIR confirmed that aurein interacts differently with the lipid rafts. The results gathered from this study provided new insights on the interaction of aurein. On the other hand, drug-drug interaction issues continue to present a major dilemma for the clinician caring for complex patients such as those infected with infectious disease. This study has examined the interaction of aurein with quinine, primaquine, and chloroquine. Significant interactions between aurein and antimalarials occured at a higher concentration of antimalarials. Interactions between aurein and anti-malarials reveal a strong interaction between aurein and primaquine. Interactions between aurein and quinine or chloroquine were found to be weak and negligible. FTIR, TGA, and DSC may be used in a complementary way to gain insights into the possible drug-drug interactions involving aurein. These studies are needed to initiate in vivo controlled

关键词： Aurein Fluorescence DPPC SPm cholesterol DPPC-SPm-CHOL Quinine Antimalarials

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Cytotoxicity, Toxicity and Anticancer Activity of manuka Honey, Saudi’s Honey and Peganum harmala Plant against Cancer Cells

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Journal of Biosciences and medicines 2024年第2期12卷 311-325页

作者： naif.m. alhawiti Elber-Lewis myles Anaif.m. Alhewaitey Yousef m. Almutairi Fadhah m. alhawiti CAHFS University of California Davis Davis USA Department of Biological Science Tennessee State University Nashville Tennessee USA Department of Chemistry University of Tabuk Tabuk Saudi Arabia ministry of Health East Jeddah General Hospital Jeddah Saudi Arabia

Cancer occurs when the body’s cells grow beyond the usual control. Normal body cells multiply in a controlled manner and undergo apoptosis when the body no longer needs them. Different types of cancers exist, and the common ones include breast, cervical, prostate, lung, colon, and skin cancers. Several factors have been associated with cancers, and these factors include poor dieting, exposure to harmful chemicals and radiation, weak immune system, and genetics. Cancer presents an enormous health threat in the modern world and thus the need to identify an effective treatment. The conventional treatments used in the management of cancer include chemotherapy and physiotherapy. These forms of cancer treatments usually have enormous side effects on the subjects. In this respect, an alternative form of treatment would be effective in managing cancer patients. A substantial number of natural products have been observed to be effective in the management of cancer. These natural products include plants and other natural substances such as honey. This study focuses on the efficiency of natural products in the treatment of cancer. Also, the anticancer effects of Peganum harmala, manuka honey, and Saudi honey will be analyzed. Bee honey and Peganum harmala have been traditionally used in the treatment of cancer. The extracts from Peganum harmala plant have also been shown to exhibit divers’ antitumor effects similar to the mode of action of a vast number of anticancer agents. These established hypotheses thus give the rationale for this study. In this experiment, extracts were obtained from Peganum harmala leaves and exposed to cervical, lung, and prostate cancer cells. Similarly, solutions of manuka honey and Saudi honey were exposed to the cervical, lung, and prostate cancer cells. The experiment duration was 24 hours, which obtained results were recorded and analyzed. Peganum harmala extracts inhibit cancer cell growth at different and achievable concentrations. manuka honey

关键词： Peganum harmala manuka Honey Saudi Honey Anticancer Apoptosis Natural Products

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Effects of Supplemental Glutamine and Lysine on Growth Performance of Broiler Chickens

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Open Journal of Animal Sciences 2024年第2期14卷 101-122页

作者： Ali F. Alsogair naif.m. alhawiti Samuel N. Nahashon National Center for Wildlife Riyadh KSA California Animal Health and Food Safety Laboratory University of California Davis Davis USA Department of Agricultural and Environmental Sciences College of Agriculture Tennessee State University Nashville Tennessee USA

The optimum levels of Lysine and Glutamine needed for growth performance and maintenance of the chicken broilers were evaluated in a randomized 3 × 4 factorial arrangement of dietary treatments. The battery cages measured 99 × 66 × 25 cm that can be sufficient for 5 birds. Day old Chicken broilers totaling 180 were assigned to dietary treatments comprising of 3 concentrations of Lysine (0.85, 1.14, and 1.42) each in combination with 4 concentrations of Glutamine (0, 1, 2, and 3). Each dietary treatment was replicated 3 times and each replication had 5 birds. The birds were given feed and water ad libitum with a 23-hour light regimen for a period of 4 weeks. Then, the experimental birds were evaluated for body weight gain, feed consumption, and feed conversion in order to determine their optimum requirement for dietary Lysine and Glutamine. Based on the findings of this study, the highest performance was observed in birds fed the diet supplemented with 1.42 lysine and 1% glutamine, but the highest improvement in feed conversion was observed in diet contain 1.14 and 1.42 with 1% and 3% glutamine, respectively. Birds fed 1.42 lysine and 1% glutamine had the highest total body weight gain and feed consumption. The lysine requirements in the diet for Chicken are between 1.14 and 1.42 with glutamine level of 1%.

关键词： Broiler Chickens Lysine Glutamine Amino Acid Dietary Protein Essentials AAs Non-Essential Amino Acids

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Bayesian and Non-Bayesian Analysis for the Sine Generalized Linear Exponential model under Progressively Censored Data

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Computer modeling in Engineering & Sciences 2024年第9期140卷 2795-2823页

作者： naif Alotaibi A.S.Al-moisheer Ibrahim Elbatal mohammed Elgarhy Ehab m.Almetwally Department of mathematics and Statistics Faculty of ScienceImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia Department of mathematics College of ScienceJouf UniversityP.O.Box 848Sakaka72351Saudi Arabia mathematics and Computer Science Department Faculty of ScienceBeni-Suef UniversityBeni-Suef62521Egypt Department of Basic Sciences Higher Institute of Administrative SciencesBelbeisEgypt Faculty of Business Administration Delta University for Science and TechnologyGamasa11152Egypt

This article introduces a novel variant of the generalized linear exponential(GLE)distribution,known as the sine generalized linear exponential(SGLE)*** SGLE distribution utilizes the sine transformation to enhance its *** updated distribution is very adaptable and may be efficiently used in the modeling of survival data and dependability *** suggested model incorporates a hazard rate function(HRF)that may display a rising,J-shaped,or bathtub form,depending on its unique *** model includes many well-known lifespan distributions as separate *** suggested model is accompanied with a range of statistical *** model parameters are examined using the techniques of maximum likelihood and Bayesian estimation using progressively censored *** order to evaluate the effectiveness of these techniques,we provide a set of simulated data for testing *** relevance of the newly presented model is shown via two real-world dataset applications,highlighting its superiority over other respected similar models.

关键词： Sine G family generalized linear failure rate progressively censored data moments maximum likelihood estimation Bayesian estimation simulation

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Antibacteria Activity of Peganum harmala and Haloxylon salicornicum Leaves Extracts

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Advances in microbiology 2024年第2期14卷 122-136页

作者： naif.m. alhawiti Agnes K. Nthenge Waeel H. Alramadhan William Boadi Abdulrahman F. Alqahtani Elber-Lewis myles CAHFS University of California Davis USA Department of Agricultural and Environmental Sciences College of Agriculture Tennessee State University Nashville USA Department of Biological Science Tennessee State University Nashville USA Department of Chemistry Tennessee State University Nashville USA Saudi Food and Drug Authority Riyadh Saudi Arabia

The use of antibiotics in humans and animals has been marked as a significant step in health due to their effectiveness in controlling and treating bacterial infections. The misuse and overuse of antibiotics have been identified as risk factors for bacterial resistance since microorganisms adapt and develop mechanisms to defend against antibiotics. According to the Centers for Disease Protection and Control (CDC), around 23,000 individuals die every year in the United States due to antibiotic resistance complications. As a result, a demand for alternative treatments has been a goal for scientists as the microbes adapt to selective pressure. The aim of this study is to test the antibacterial activity of leaf extracts of Peganum harmala and Haloxylon salicornicum on both Gram-positive and Gram-negative bacteria on various mediums. The results of the study showed that both P. harmala and H. salicornicum inhibited the bacterial growth in two different media. The results were also compared with different common antibiotics used in both human’s and animal’s fields and showed a promising outcome as alternative antibiotics.

关键词： Peganum harmala Haloxylon salicornicum Antibiotics Resistance medicinal Plants Gram-Positive Gram-Negative

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Anticancer Activity of Peganum harmala and Haloxylon salicornicum Leaf Extracts on Lung Cancer A549 and Prostate Cancer PC-3 Cell Lines

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American Journal of Plant Sciences 2023年第11期14卷 1360-1374页

作者： naif.m. alhawiti Waeel H. Alramadhan William Boadi Elbert Lewis myles Department of Biological Science Tennessee State University Nashville TN USA Department of Chemistry Tennessee State University Nashville TN USA

Cancer is a worldwide disease that ranks as the second-largest cause of death after cardiovascular disease. In 2019, the estimated number of cancer deaths was around 10 million worldwide and 600,000 in the United States. Due to the high side effects of the available treatments for cancer, such as chemotherapy and radiotherapy, a demand for alternative treatments has been a goal for scientists with less toxicity and side effects. Lung cancer is the most common type of cancer worldwide and the leading cause of death in the United States. In addition, prostate cancer is the second-leading cause of cancer death in American men after lung cancer. Natural sources discovered to have therapeutic medicinal properties against human diseases are the plants Peganum harmala and Haloxylon salicornicum. The aim of this study is to test the anticancer activity of leaf extracts of Peganum harmala and Haloxylon salicornicum on lung cancer (A549) and prostate cancer (PC3) cell lines. The anticancer activity of P. harmala and H. salicornicum was studied using the assays: crystal violet viability, lipid peroxidation, and caspase-3 techniques, which were evaluated in vitro on two human cancer cell lines. The results of the study showed that both plants’ extracts reduced the viability of both cancer cell lines, which depended on the concentration of the extract. Also, P. harmala showed more potent activity against both types of cancer than H. salicornicum. P. harmala and H. salicornicum decreased the lipid peroxidation that induces cancer as well as increased the expression of caspase-3, which causes apoptosis and cell death. This study concluded that P. harmala and H. salicornicum leaf extracts showed significant anticancer properties, which might be due to the presence of phytochemicals, including flavonoids and phenolics.

关键词： Peganum harmala Haloxylon salicornicum Lung Cancer Prostate Cancer Lipid Peroxidation Caspase-3 Apoptosis

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Antioxidant therapy in male infertility： fact or fiction？

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Asian Journal of Andrology 2011年第3期13卷 374-381,510页

作者： Armand Zini naif AI-Hathal Division of Urology Department of Surgery Royal Victoria Hospital McGill University Montreal Que. H3T 1M5 Canada

Infertile men have higher levels of semen reactive oxygen species （ROS） than do fertile men. High levels of semen ROS can cause sperm dysfunction, sperm DNA damage and reduced male reproductive potential. This observation has led clinicians to treat infertile men with antioxidant supplements. The purpose of this article is to discuss the rationale for antioxidant therapy in infertile men and to evaluate the data on the efficacy of dietary and in vitro antioxidant preparations on sperm function and DNA damage. To date, most clinical studies suggest that dietary antioxidant supplements are beneficial in terms of improving sperm function and DNA integrity. However, the exact mechanism of action of dietary antioxidants and the optimal dietary supplement have not been established. moreover, most of the clinical studies are small and few have evaluated pregnancy rates. A beneficial effect of in vitro antioxidant supplements in protecting spermatozoa from exogenous oxidants has been demonstrated in most studies; however, the effect of these antioxidants in protecting sperm from endogenous ROS, gentle sperm processing and cryopreservation has not been established conclusively.

关键词： antioxidant male infertility oxidative stress sperm DNA fragmentation vitamins

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A New Hybrid model for Segmentation of the Skin Lesion Based on Residual Attention U-Net

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Computers, materials & Continua 2023年第6期75卷 5177-5192页

作者： Saleh naif Almuayqil Reham Arnous Noha Sakr magdy m.Fadel Department of Information Systems College of Computer and Information SciencesJouf UniversitySakakaSaudi Arabia Department of Communications and Electronics Delta Higher Institute for Engineering and Technology(DHIET)MansouraEgypt Computers Engineering and Control Systems Department Faculty of EngineeringMansoura UniversityMansouraEgypt

Skin segmentation participates significantly in various biomedical applications,such as skin cancer identification and skin lesion *** paper presents a novel framework for segmenting the *** framework contains two main stages:The first stage is for removing different types of noises from the dermoscopic images,such as hair,speckle,and impulse noise,and the second stage is for segmentation of the dermoscopic images using an attention residual U-shaped Network(U-Net).The framework uses variational Autoencoders(VAEs)for removing the hair noises,the Generative Adversarial Denoising Network(DGAN-Net),the Denoising U-shaped U-Net(D-U-NET),and Batch Renormalization U-Net(Br-U-NET)for remov-ing the speckle noise,and the Laplacian Vector median Filter(mLVmF)for removing the impulse *** the second main stage,the residual attention u-net was used for *** framework achieves(35.11,31.26,27.01,and 26.16),(36.34,33.23,31.32,and 28.65),and(36.33,32.21,28.54,and 27.11)for removing hair,speckle,and impulse noise,respectively,based on Peak Signal Noise Ratio(PSNR)at the level of(0.1,0.25,0.5,and 0.75)of *** framework also achieves an accuracy of nearly 94.26 in the dice score in the process of segmentation before removing noise and 95.22 after removing different types of *** experiments have shown the efficiency of the used model in removing noise according to the structural similarity index measure(SSIm)and PSNR and in the segmentation process as well.

关键词： Skin tumor speckle noise impulse noise hair noise deep learning segmentation

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Hydromagnetic peristaltic transport of copper-water nanofluid with temperature-dependent effective viscosity

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Particuology 2016年第4期14卷 133-140页

作者： Fahad m. Abbasi Tasawar Hayat Sabir A. Shehzad Fuad Alsaadi naif Altoaibi Department of mathematics COMSATS Institute of lnformation Technology Islamabad 44000 Pakistan Department of mathematics Quaid-l-Azam University 45320 Islamabad 44000 Pakistan Department of Electrical and Computer Engineering Faculty of Engineering King Abdulaziz University Jeddah Saudi Arabia Department of mathematics COMSATS Institute of Information Technology Sahiwal Pakistan

The unique chemical mechanical, and thermodynamic properties of nanofluids make them a subject of great interest for scientists from all domains. Such fluids are of particular significance in biomedical engineering owing to their vast and novel applications in modern drug delivery systems; for example, mixed convective peristaltic flow of water-based nanofluids under the influence of an externally applied magnetic field is of particular significance. Hence, a lot of research has focused on peristalsis in the presence of velocity and thermal slip effects. An empirical relation for the effective viscosity of the nanofluid is proposed here for the first time. The viscosity of the nanofluid varies with temperature and nanoparticle volume fraction. Numerical simulation of the resulting nonlinear system of equations is presented for different quantities of interest. The results indicate that the maximum velocity and temperature of the copper-water nanofluid increase for larger variable viscosity parameter. The pressure gradient in the wider part of the channel is also found to increase as a function of the variable viscosity parameter. The variable viscosity parameter also influences the size of the trapped bolus. An increase in the nanoparticle volume fraction reduces the reflux phenomenon in a peristaltic flow.

关键词： Temperature dependent effective viscosity Copper-water nanofluid Peristalsis Slip effect magnetohydrodynamics

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