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991.
A. B. Ibrahim T. M. Sakr O. M. A. Khoweysa M. A. Motaleb A. Abd El-Bary M. T. El-Kolaly 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):179-186
The aim of this study is the formulation of a new radiopharmaceutical for imaging solid tumor bearing. Gemcitabine is a nucleoside analogue used as chemotherapeutic agent. Gemcitabine was formulated and radiolabeled with one of the most important diagnostic radioactive isotopes (technetium-99m) to be investigated in solid tumor imaging. The labeling parameters such as gemcitabine amount, stannous chloride amount, pH of the reaction mixture, and reaction time were optimized. 99mTc–gemcitabine was prepared at pH 9 with a maximum labeling yield of 96 ± 0.3 % without any notable decomposition at room temperature over a period of 8 h. The preclinical evaluation and biodistribution in solid tumor bearing mice showed that 99mTc–gemcitabine had solid tumor selectivity, preclinical high biological accumulation in tumor cells and high retention. Tumor/normal muscle (T/NT) ratios increased with time showing high T/NT ratio (T/NT = 4.9 ± 0.27 at 120 min post injection) and high Tumor/Blood ratio (3.4 ± 0.06), suggesting 99mTc–gemcitabine as a novel solid tumor imaging agent. 相似文献
992.
Nurul Ain Mazlan Thahira Begum S. A. Ravoof Edward R. T. Tiekink Mohamed Ibrahim Mohamed Tahir Abhi Veerakumarasivam Karen A. Crouse 《Transition Metal Chemistry》2014,39(6):633-639
Salicylaldehyde-4-methylthiosemicarbazone (H2MTSali) has been prepared via the condensation reaction of 4-methyl-3-thiosemicarbazide and salicylaldehyde. Four new mixed-ligand copper(II) and nickel(II) complexes with a general formula [M(MTSali)L] (M = Cu2+ or Ni2+; L = co-ligand) were synthesized, where L is either imidazole (im) or benzimidazole (bzim). The Schiff base and its mixed-ligand complexes were characterized by IR and UV/Vis spectroscopy, and the complexes by molar conductivity and magnetic susceptibility measurements. The spectroscopic data indicated that the Schiff base behaves as a tridentate ONS donor ligand coordinating via the phenoxide-oxygen, azomethine-nitrogen, and thiolate-sulphur atoms. Magnetic data indicate a square planar environment for the nickel(II) complexes while molar conductance values indicate that the metal complexes are essentially non-electrolytes in DMSO solution. X-ray crystallography shows Cu(MTSali)bzim (1) and Ni(MTSali)bzim (3) to be isostructural, with the metal(II) ions being coordinated by a N2OS donor set that defines an approximate square planar geometry; in both cases, the benzimidazole is splayed with respect to the coordination plane. The copper(II) complexes were active against MDA-MB-231 and MCF-7 breast cancer cell lines, more so than H2MTSali, whereas the nickel(II) complexes were inactive. 相似文献
993.
Sivanesan Raja Kumar Elvy Suhana Mohd Ramli Nurul Alimah Abdul Nasir Nafeeza Mohd Ismail Nur Azlina Mohd Fahami 《Molecules (Basel, Switzerland)》2021,26(13)
Obesity and hyperlipidemia are metabolic dysregulations that arise from poor lifestyle and unhealthy dietary intakes. These co-morbidity conditions are risk factors for vascular diseases. Piper sarmentosum (PS) is a nutritious plant that has been shown to pose various phytochemicals and pharmacological actions. This study aimed to investigate the effect of PS on obesity and hyperlipidemia in an animal model. Forty male Wistar rats were randomly divided into five experimental groups. The groups were as follows: UG—Untreated group; CTRL—control; FDW—olive oil + 20% fructose; FDW-PS—PS (125 mg/kg) + 20% fructose; FDW-NGN—naringin (100 mg/kg) + 20% fructose. Fructose drinking water was administered daily for 12 weeks ad libitum to induce metabolic abnormality. Treatment was administered at week 8 for four weeks via oral gavage. The rats were sacrificed with anesthesia at the end of the experimental period. Blood, liver, and visceral fat were collected for further analysis. The consumption of 20% fructose water by Wistar rats for eight weeks displayed a tremendous increment in body weight, fat mass, percentage fat, LDL, TG, TC, HMG-CoA reductase, leptin, and reduced the levels of HDL and adiponectin as well as adipocyte hypertrophy. Following the treatment period, FDW-PS and FDW-NGN showed a significant reduction in body weight, fat mass, percentage fat, LDL, TG, TC, HMG-CoA reductase, and leptin with an increment in the levels of HDL and adiponectin compared to the FDW group. FDW-PS and FDW-NGN also showed adipocyte hypotrophy compared to the FDW group. In conclusion, oral administration of 125 mg/kg PS methanolic extract to fructose-induced obese rats led to significant amelioration of obesity and hyperlipidemia through suppressing the adipocytes and inhibiting HMG-CoA reductase. PS has the potential to be used as an alternative or adjunct therapy for obesity and hyperlipidemia. 相似文献
994.
Thymoquinone Loaded Topical Nanoemulgel for Wound Healing: Formulation Design and In-Vivo Evaluation
Mohammed S. Algahtani Mohammad Zaki Ahmad Ibrahim Ahmed Shaikh Basel A. Abdel-Wahab Ihab Hamed Nourein Javed Ahmad 《Molecules (Basel, Switzerland)》2021,26(13)
Thymoquinone is a natural bioactive with significant therapeutic activity against multiple ailments including wound healing. The poor aqueous solubility and low skin permeability limit its therapeutic efficacy. The present investigation aimed to improve the biopharmaceutical attributes of thymoquinone to enhance its topical efficacy in wound healing. A nanoemulsion-based hydrogel system was designed and characterized as a nanotechnology-mediated drug delivery approach to improve the therapeutic efficacy of thymoquinone, utilizing a high-energy emulsification technique. The black seed oil, as a natural home of thymoquinone, was utilized to improve the drug loading capacity of the developed nanoemulsion system and reduced the oil droplet size to <100 nm through ultrasonication. The influence of formulation composition, and the ultrasonication process conditions, were investigated on the mean globule size and polydispersity index of the generated nanoemulsion. Irrespective of surfactant/co-surfactant ratio and % concentration of surfactant/co-surfactant mixture, the ultrasonication time had a significant (p < 0.05) influence on the mean droplet size and polydispersity index of the generated nanoemulsion. The developed nanoemulgel system of thymoquinone demonstrated the pseudoplastic behavior with thixotropic properties, and this behavior is desirable for topical application. The nanoemulgel system of thymoquinone exhibited significant enhancement (p < 0.05) in skin penetrability and deposition characteristics after topical administration compared to the conventional hydrogel system. The developed nanoemulgel system of thymoquinone exhibited quicker and early healing in wounded Wistar rats compared to the conventional hydrogel of thymoquinone, while showing comparable healing efficacy with respect to marketed silver sulfadiazine (1%) cream. Furthermore, histopathology analysis of animals treated with a developed formulation system demonstrated the formation of the thick epidermal layer, papillary dermis along with the presence of extensive and organized collagen fibers in newly healed tissues. The outcome of this investigation signifies that topical delivery of thymoquinone through nanoemulgel system is a promising candidate which accelerates the process of wound healing in preclinical study. 相似文献
995.
Adel A.-H. Abdel-Rahman Amira K. F. Shaban Ibrahim F. Nassar Dina S. EL-Kady Nasser S. M. Ismail Samy F. Mahmoud Hanem M. Awad Wael A. El-Sayed 《Molecules (Basel, Switzerland)》2021,26(13)
New pyridine, pyrazoloyridine, and furopyridine derivatives substituted with naphthyl and thienyl moieties were designed and synthesized starting from 6-(naphthalen-2-yl)-2-oxo-4-(thiophen-2-yl)-1,2-dihydropyridine-3-carbonitrile (1). The chloro, methoxy, cholroacetoxy, imidazolyl, azide, and arylamino derivatives were prepared to obtain the pyridine-−C2 functionalized derivatives. The derived pyrazolpyridine-N-glycosides were synthesized via heterocyclization of the C2-thioxopyridine derivative followed by glycosylation using glucose and galactose. The furopyridine derivative 14 and the tricyclic pyrido[3′,2′:4,5]furo[3,2-d]pyrimidine 15 were prepared via heterocyclization of the ester derivative followed by a reaction with formamide. The newly synthesized compounds were evaluated for their ability to in vitro inhibit the CDK2 enzyme. In addition, the cytotoxicity of the compounds was tested against four different human cancer cell lines (HCT-116, MCF-7, HepG2, and A549). The CDK2/cyclin A2 enzyme inhibitory results revealed that pyridone 1, 2-chloro-6-(naphthalen-2-yl)-4-(thiophen-2-yl)nicotinonitrile (4), 6-(naphthalen-2-yl)-4-(thiophen-2-yl)-1H-pyrazolo[3,4-b]pyridin-3-amine (8), S-(3-cyano-6-(naphthaen-2-yl)-4-(thiophen-2-yl)pyridin-2-yl) 2-chloroethanethioate (11), and ethyl 3-amino-6-(naphthalen-2-yl)-4-(thiophen-2-yl)furo[2,3-b]pyridine-2-carboxylate (14) are among the most active inhibitors with IC50 values of 0.57, 0.24, 0.65, 0.50, and 0.93 µM, respectively, compared to roscovitine (IC50 0.394 μM). Most compounds showed significant inhibition on different human cancer cell lines (HCT-116, MCF-7, HepG2, and A549) with IC50 ranges of 31.3–49.0, 19.3–55.5, 22.7–44.8, and 36.8–70.7 μM, respectively compared to doxorubicin (IC50 40.0, 64.8, 24.7 and 58.1 µM, respectively). Furthermore, a molecular docking study suggests that most of the target compounds have a similar binding mode as a reference compound in the active site of the CDK2 enzyme. The structural requirements controlling the CDK2 inhibitory activity were determined through the generation of a statistically significant 2D-QSAR model. 相似文献
996.
We proposed a simple low-cost acrylic and metal-based Y-branch plastic optical fiber (POF) splitter which utilizes a low cost
optical polymer glue NOA63 as the main waveguiding medium at the waveguide taper region. The device is composed of three sections:
an input POF waveguide, a middle waveguide taper region and output POF waveguides. A desktop high speed CNC engraver is utilized
to produce the mold inserts used for the optical devices. Short POF fibers are inserted into the engraved slots at the input
and output ports. UV curable optical polymer glue NOA63 is injected into the waveguide taper region and cured. The assembling
is completed when the top plate is positioned to enclose the device structure and connecting screws are secured. Both POF
splitters have an average insertion loss of 7.8 dB, coupling ratio of 55: 45 and 57: 43 for the acrylic and metal-based splitters
respectively. The devices have excess loss of 4.82 and 4.73 dB for the acrylic and metal-based splitters respectively. 相似文献
997.
Amir Reza Sadrolhosseini Mohd Maarof Moksin W. Mahmood Mat Yunus Zainal Abidin Talib Mahnaz M. Abdi 《Optical Review》2011,18(4):331-337
Copper corrosion is one of the important parameters used for evaluating the quality of biodiesel. In this work, a polypyrrole-chitosan
sensing layer was utilized for the detection of Cu2+ in biodiesel using the surface plasmon resonance technique. With the sensitivity of this sensor being about 0.1 ppm, different
corrosion levels could be recognized in samples that were classified as class 1a according to the standard copper strip test. 相似文献
998.
Mohammed M. Rahman Aslam Jamal Sher Bahadar Khan Mohd Faisal 《Journal of nanoparticle research》2011,13(9):3789-3799
The production of low-dimensional nanoparticles (NPs) with appropriate surface modification has attracted increasing attention
in biological, biochemical, and environmental applications including chemical sensing, photocatalytic degradation, separation,
and purification of toxic molecules from the matrices. In this study, iron oxide NPs have been prepared by hydrothermal method
using ferric chloride and urea in aqueous medium under alkaline condition (pH 9 ~ 10). As-grown low-dimensional NPs have been
characterized by UV–vis spectroscopy, FT-IR, X-ray diffraction, Field emission scanning electron microscopy, Raman spectroscopy,
High-resolution Transmission electron microscopy, and Electron Diffraction System. The uniformity of the NPs size was measured
by the scanning electron microscopy, while the single phase of the nanocrystalline β-Fe2O3 was characterized using powder X-ray diffraction technique. As-grown NPs were extensively applied for the photocatalytic
degradation of acridine orange (AO) and electrochemical sensing of ammonia in liquid phase. Almost 50% photo-catalytic degradation
with AO was observed in the presence of UV sources (250 W) with NPs. β-Fe2O3 NP-coated gold electrodes (GE, surface area 0.0216 cm2) have enhanced ammonia-sensing performances in their electrical response (I–V characterization) for detecting ammonia in liquid phase. The performances of chemical sensor were investigated, and the results
exhibited that the sensitivity, stability, and reproducibility of the sensor improved significantly using β-Fe2O3 NPs on GE surface. The sensitivity was approximately 0.5305 ± 0.02 μAcm−2mM−1, with a detection limit of 21.8 ± 0.1 μM, based on a signal/noise ratio of 3 with short response time. 相似文献
999.
In this work, we constructed the equations of generalized thermoelasticity of a homogeneous isotropic hollow cylinder. The
formulation is applied in the context of the Green and Naghdi theory of types II and III. The material of the cylinder is
assumed to be homogeneous isotropic both mechanically and thermally. The problem has been solved numerically using a finite-element
method. Numerical results for the temperature distribution, displacement, radial stress, and hoop stress are represented graphically.
Comparisons are made with the results predicted by the types II and III. The results obtained in this paper can be used to
design various homogeneous thermoelastic elements under thermal load to meet special engineering requirements. 相似文献
1000.
A simple design of one-dimensional omni-directional reflector based on photonic crystal heterostructures structure has been proposed. The proposed structure consists of a periodic array of alternate layers of SiO2 and Te as the materials of low and high refractive indices, respectively. The structure considered here has three stacks of periodic structures having five layers each. The lattice period of successive stack is increased by a certain multiple (say gradual constant, δ) of the lattice period of the just preceding stack. For numerical computation, the method of transfer matrix method (TMM) has been employed. It is found that such a structure has wider reflection bands in comparison to a conventional dielectric PC structure and the width of the omni-directional reflection (ODR) bands can be enlarged by increasing the value of the gradual constant δ. 相似文献