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Genetic Relationships of Some Barley Cultivars, Based on Morphological Criteria and RAPD Fingerprinting زينب ماجد طاهر المطيري

                  Abstract: In this study, the relationship of ten Saudi Arabian local and imported barley cultivars, based on evidences derived from agro-...

Cloning and expression profiling of polycomb gene, DNA Polymerase Alpha (POLα) from tomato Solanum lycopersicum L زينب ماجد طاهر المطيري

The decision to replicate its DNA is of crucial importance for every cell and, in many organisms, is decisive for the progression through the entire cell cycle. DNA polymerases are required to maintain the integrity of the genome during DNA replication. DNA Polymerase Alpha (POLα) encodes the putative catalytic subunit of the DNA polymerase α which plays an essential role in the initiation of DNA replication. Here, we present the cloning, characterization and expression of a putative SlPOLα gene in tomato by isolating cDNA clones correspond to SlPOLα gene from tomato using primers designed from available ESTs based on conserved sequences between PcG genes in Arabidopsis thaliana and tomato. The SlPOLα cDNAs were cloned into pBS plasmid and sequenced. Both 5' and 3' RACE were generated and sequenced. The flcDNA for SlPOLα gene length was composed of 4,944 bp, containing 103 bp in the 5'UTR; 4,683 bp in the ORF; and 158 bp in 3'UTR. The translated ORF encodes a polypeptide of 1,561 amino acids. Alignment of deduced amino acids indicated that there are highly conserved regions between tomato SlPOLα predicted protein and hypothetical plant POLα gene family members. Both unrooted phylogenetic trees, constructed using maximum parsimony and maximum likelihood methods indicated that there is a close relationship between SlPOLα predicted protein and POLα protein of Mimulus guttatus. SlPOLα was strongly expressed in proliferating tissues (closed floral buds) and moderately expressed in flower tissues, while was weakly expressed in non-proliferating tissues (unripe fruit).

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Sustained-Release of Flutamide from Radiation-Crosslinked Poly(4-acryloyl morpholine-acrylic acid) Hydrogels منال فوزي أبوطالب
The present work reports the effect of radiation cross-linking on aqueous solution of 4-acryloyl morpholine (ACMO)/acrylic acid (AA) in the presence of flutamide (FLT), an anticancer drug. Use of a γ-irradiation process within 5 kGy provided an insoluble hydrogel. Ultraviolet-visible absorption, fluorescence spectroscopy, and Fourier transform infrared spectroscopy were employed to study the complex formation of FLT with ACMO and AA. The ability of the prepared ACMO/AA-based hydrogels to be used as drug carriers for anticancer-specific drug delivery system was estimated using FLT as a model drug. In vitro drug release studies in a pH 7 buffer solution show that 20%-30% of the FLT was continuously released from the FLT-incorporated ACMO/AA hydrogel within 1 day, followed by a gradual release upon 7 days under in vitro non-degradation hydrogel conditions. The recognition affinity of the ACMO/AA/FLT hydrogel is increased when synthesized in a high-concentration template solution. ...
Radiation synthesis, characterization and dye adsorption of alginate–organophilic montmorillonite nanocomposite منال فوزي أبوطالب

In this paper, the preparation, characterization and dye adsorption properties of nanocomposite (calcium

alginate/organophilic montmorillonite) (CA/OMMT) were investigated. A new nanocomposite consisting of alginate and OMMT was prepared by polymerization using -rays irradiation as initiator. Physical characteristics of CA/OMMT were studied using X-ray diffraction (XRD), infrared spectrophotometery (IR), thermal gravimetric analysis (TGA), transmission electron microscopy (TEM) and the corresponding selected area electron diffraction (SAED). Two textile dyes, acid green B and direct pink 3B, were used as model anionic dye. Factors affecting dye sorption, such as pH, sorbent concentration and temperature of each dye solution were extensively investigated. It was found from the study that the sorption of dyes by the nanocomposite is pH-dependent and maximum sorption was obtained at pH 2. The thermodynamic data showed that dye adsorption onto alginate was spontaneous, exothermic, and a physisorption reaction. On the basis of the data of the present investigation, one could conclude that the as-prepared adsorbents exhibited excellent affinity for the dye, and can be applied to treat wastewater containing anionic dyes. ...
Radiation preparation of PVA/CMC copolymers and their application in removal of dyes منال فوزي أبوطالب

Copolymer hydrogels composed of poly(vinyl alcohol) (PVA) and carboxymethyl cellulose (CMC) was

prepared by using electron beam irradiation as crosslinking agent. The copolymers were characterized by FTIR and the physical properties such as gelation. The thermal behavior and swelling properties of the prepared hydrogels were investigated as a function of PVA/CMC composition. The factors effecting adsorption capacity of acid, reactive and direct dyes onto PVA/CMC hydrogel, such as CMC content, pH value of the dye solution, initial concentration and adsorption temperature for dyes were investigated. Thermodynamic study indicated that the values the negative values ofH suggested that the adsorption process is exothermic. The value of H (38.81 kJ/mol) suggested that the electrostatic interaction is the dominant mechanism for the adsorption of dyes on hydrogel. ...
pH-Sensitive Hydrogels Based on Bovine Serum Albumin for Anticancer Drug Delivery منال فوزي أبوطالب
Protein conjugates consisting of hydroxyethyl methacrylate and acrylic acid monomers in the presence of bovine serum albumin (BSA) were prepared by gamma irradiation to examine the potential use of these hydrogels in the controlled drug release systems. The study parameter was the BSA content in the as-prepared conjugates. Polymers were characterized with FTIR, scanning electron microscopy (SEM), and swelling studies. The polymerization reaction caused the rearrangement of the BSA carbonyl hydrogen bonding and finally led to the modification of the BSA secondary structure as proved by FTIR. SEM proved that the prepared conjugates matrices are porous, with a three-dimensional interconnected microstructure. The swelling kinetics of the hydrogels and the release dynamics of an anticancer model drug (flutamide) have been studied. High equilibrium swelling values, up to 1550%, could be observed and were correlated with the increase in pH, temperature, and BSA content. The mechanism of swelling changed from Fickian to non- Fickian by reducing the acidity of the medium. This study proved that there is a direct relationship between the protein content in the conjugates and both the loaded and the released drug. These pH responsive conjugates may be exploited for the delivery of flutamide. ...
Radiation synthesis of poly[(dimethylaminoethyl methacrylate)- co-(ethyleneglycol dimethacrylate)] hydrogels and its application as a carrier for anticancer delivery منال فوزي أبوطالب
The use of hydrogels as carriers for anticancer delivery has been a subject of significant recent research. In our recent work, we have shown that diffusion-controlled delivery of flutamide from hydrogels containing poly (dimethylaminoethyl methacrylate (DMAEMA)/ethyleneglycol dimethacrylate (EGDMA)) can be possible and controlled by the three-dimensional structure. Hydrogels based essentially on dimethylaminoethyl methacrylate and different ratios of ethyleneglycol dimethacrylate monomers were synthesized using gamma radiation copolymerization. The influence of copolymer composition and pH value of the surrounding medium on swelling behavior into the glassy polymer were discussed. The results showed that the ratio of EGDMA in the comonomer feeding solution has a great effect on the gel fraction and water content in the final hydrogel. In this regard, it was observed that the increase of EGDMA ratio decreased these properties. The ability of the prepared copolymer to be used as drug carrier for anticancer drug-delivery system was estimated using flutamide as a model drug. In vitro drug-release studies in different buffer solutions show that the basic parameters affecting the drug release behavior of hydrogel are the pH of the solution and DMAEMA content of hydrogel. ...
Immobilization of Urease on (HEMA/IA) Hydrogel Prepared by Gamma Radiation منال فوزي أبوطالب
synthesized by gamma radiation induced radical polymerization, in order to examine the potential use of these hydrogels in immobilization of Citrullus vulgaris urease. Gelation and Swelling properties of PHEMA and copolymeric P (HEMA/IA) hydrogels with different IA contents (96.5/3.5, 94.4/5.6 and 92.5/7.5 mol) were studied in a wide pH range. Initial studies of so-prepared hydrogels show interesting pH sensitivity in swelling and immobilization. C. vulgaris urease was immobilized on HEMA/IA (92.5/7.5) at 6 kGy with 41.3% retention of activity. The properties of free and immobilized urease were compared. Immobilized urease maintained a higher relative activity than free urease at both lower and higher pH levels, indicating that the immobilized urease was less sensitive to pH changes than the free urease. The Km value of the immobilized urease was approximately 2 times higher than that of the free urease. Temperature stability was improved for immobilized enzyme. The free form exhibited a loss about 80% of activity upon incubation for 15 min at 80◦C. The influence of various heavy metal ions at the concentration of l mM was improved after enzyme immobilization. The immobilization of C. vulgaris urease on HEMA/IA (92.5/7.5) at 6 kGy showed a residual activity of 47 % after 4 reuses. ...
Hybrid Nanocomposite Prepared by Graft Copolymerization of 4-Acryloyl morpholine onto Chitosan in the Presence of Organophilic Montmorillonite منال فوزي أبوطالب
Organophilic montmorillonite (OMMT) was synthesized by cationic exchange between Na-MMT and Vinyl benzyl triphenyl phosphonium chloride in an aqueous solution. A new nanocomposite consisting of 4-acryloyl morpholine-chitosan and OMMT was prepared by γ -ray irradiation polymerization. The intercalation spacing of these nanocomposites was investigated with X-ray diffraction and its thermal stabilities by adding nanocomposites were characterized by thermal gravimetric analysis. The nanocomposites showed improved resistance to water absorption. The most interesting application of the nanocomposite is its ability for adsorption purification of waste water containing acid dyes.One of the objectives in this study was to develop new and active prepared copolymers which can be examined for their antimicrobial activities. It was found that the copolymer nanocomposite based on phosphonium group and some heavy metal ions in its structure having broad spectrum against pathogenic bacteria such as Staphylococcus aurius, Escherichia coli and Aspergillus flavus fungi. ...
Radiation Synthesis and Characterization of Polyvinyl Alcohol/Methacrylic Acid–Gelatin Hydrogel for Vitro Drug Delivery منال فوزي أبوطالب
This paper describes the use of gamma radiation Co60 source as crosslinker for the preparation of gelatin based pharmaceutical hydrogels. Glutaraldehyde (GLU) (0.5% v/v) was incorporated after irradiation to crosslink the gelatin chains. Several samples of hydrogels P(PVA/MAA) were prepared by varying the ratio of PVA and MAA monomer. The swelling behavior of these hydrogels was investigated as a function of doses, concentration, copolymer composition (PVA:MAA ratio) and pH of the immersion medium. It was found that the swelling of test hydrogels was larger (8) in the alkaline medium than in the acid medium (3) and at pH 5.3 was the smallest (3). The characterizations of the hydrogels were performed by FTIR, SEM to evaluate the relationship of the structure and morphology of the hydrogels. The adsorption isotherm studies by batching techniques under the effect of different initial feed concentrations of drugs and MAA content of the adsorbent hydrogels will be investigated. Furthermore, for the evaluation of the pH effect on drug release from the prepared hydrogels, we studied chlortetracycline HCl and amoxicillin trihydrate release profiles at pH 2.2, 5.0 and 7.5. The pH-sensitivity of the novel polyelectrolyte complex would make an interesting drug delivery system. ...
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