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91.
We develop generalized coherent states based on the Gazeau–Klauder formalism for the triangular well potential and discuss some of their properties. We study the Mandel parameter and the second-order correlation function for investigating the statistical properties. Moreover, we present the spatiotemporal evolution. 相似文献
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94.
Motwani SK Chopra S Ahmad FJ Khar RK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,68(2):250-256
New, simple, cost effective, accurate and reproducible UV-spectrophotometric methods were developed and validated for the estimation of moxifloxacin in bulk and pharmaceutical formulations. Moxifloxacin was estimated at 296 nm in 0.1N hydrochloric acid (pH 1.2) and at 289 nm in phosphate buffer (pH 7.4). Beer's law was obeyed in the concentration range of 1-12 microg ml(-1) (r2=0.9999) in hydrochloric acid and 1-14 microg ml(-1) (r2=0.9998) in the phosphate buffer medium. The apparent molar absorptivity and Sandell's sensitivity coefficient were found to be 4.63 x 10(4) l mol(-1) cm(-1) and 9.5 ng cm(-2)/0.001 A in hydrochloric acid; and 4.08 x 10(4) l mol(-1) cm(-1) and 10.8 ng cm(-2)/0.001 A in phosphate buffer media, respectively indicating the high sensitivity of the proposed methods. These methods were tested and validated for various parameters according to ICH guidelines. The detection and quantitation limits were found to be 0.0402, 0.1217 microg ml(-1) in hydrochloric acid and 0.0384, 0.1163 microg ml(-1) in phosphate buffer medium, respectively. The proposed methods were successfully applied for the determination of moxifloxacin in pharmaceutical formulations (tablets, i.v. infusions, eye drops and polymeric nanoparticles). The results demonstrated that the procedure is accurate, precise and reproducible (relative standard deviation <2%), while being simple, cheap and less time consuming and hence can be suitably applied for the estimation of moxifloxacin in different dosage forms and dissolution studies. 相似文献
95.
Chibber S Hassan I Farhan M Naseem I 《Journal of photochemistry and photobiology. B, Biology》2011,104(3):387-393
Methotrexate (MTX) an anti-cancer drug as well as a photosensitizer is able to generate reactive oxygen species (ROS). Cu (II) is present associated with chromatin in cancer cells and has been shown to be capable of mediating the action of several anti-cancer drugs through production of ROS. The objective of the present study is to determine Cu (II) mediated anti-cancer mechanism of MTX under photoilluminated condition as well as alone, using alkaline single cell gel electrophoresis (comet assay). We have shown that cellular DNA breakage was enhanced when Cu (II) is used with MTX as compared to MTX alone. It is also shown that MTX alone as well as in combination with Cu (II) is able to generate oxidative stress in lymphocyte which is inhibited by scavengers of ROS but the pattern of inhibition was differential as was also demonstrated by plasmid nicking assay. Thus, we can say that MTX exhibit pro-oxidant action in presence of white light which gets elevated in presence of Cu (II). Hence, we propose that the mobilization of endogenous copper is possibly involved in killing of cancer cells by MTX during chemo-radio therapy besides acting as antifolate. 相似文献
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Fatima Rashid Anam Javaid Mahmood-ur-Rahman Usman Ali Ashfaq Muhammad Sufyan Abdulrahman Alshammari Metab Alharbi Muhammad Atif Nisar Mohsin Khurshid 《Molecules (Basel, Switzerland)》2022,27(17)
Diabetes mellitus (DM) is a metabolic disease caused by improper insulin secretion leading to hyperglycemia. Syzygium cumini has excellent therapeutic properties due to its high levels of phytochemicals. The current research aimed to evaluate the anti-diabetic potential of S. cumini plant’s seeds and the top two phytochemicals (kaempferol and gallic acid) were selected for further analysis. These phytochemicals were selected via computational tools and evaluated for α-Glucosidase inhibitory activity via enzymatic assay. Gallic acid (IC50 0.37 µM) and kaempferol (IC50 0.87 µM) have shown a stronger α-glucosidase inhibitory capacity than acarbose (5.26 µM). In addition, these phytochemicals demonstrated the highest binding energy, hydrogen bonding, protein–ligand interaction and the best MD simulation results at 100 ns compared to acarbose. Furthermore, the ADMET properties of gallic acid and kaempferol also fulfilled the safety criteria. Thus, it was concluded that S. cumini could potentially be used to treat DM. The potential bioactive molecules identified in this study (kaempferol and gallic acid) may be used as lead drugs against diabetes. 相似文献
98.
Yan Liu Xin Meng Han Wang Yan Sun Si-Yi Wang Yi-Kai Jiang Adnan Mohammed Algradi Anam Naseem Hai-Xue Kuang Bing-You Yang 《Molecules (Basel, Switzerland)》2022,27(18)
Eight new inositol derivatives, solsurinositols A–H (1–8), were isolated from the 70% EtOH extract of the leaves of Solanum capsicoides Allioni. Careful isolation by silica gel column chromatography followed by preparative high-performance liquid chromatography (HPLC) allowed us to obtain analytically pure compounds 1–8. They shared the same relative stereochemistry on the ring but have different acyl groups attached to various hydroxyl groups. This was the first time that inositol derivatives have been isolated from this plant. The chemical structures of compounds 1–8 were characterized by extensive 1D nuclear magnetic resonance (NMR) and 2D NMR and mass analyses. Meanwhile, the in vitro anti-inflammatory activity of all compounds was determined using lipopolysaccharide (LPS)-induced BV2 microglia, and among the isolates, compounds 5 (IC50 = 11.21 ± 0.14 µM) and 7 (IC50 = 14.5 ± 1.22 µM) were shown to have potential anti-inflammatory activity. 相似文献
99.
Ghazala Muteeb Md Tabish Rehman Mohamed F. AlAjmi Mohammad Aatif Mohd Farhan Sheeba Shafi 《Molecules (Basel, Switzerland)》2022,27(18)
New Delhi metallo-β-lactamase-1 (NDM-1), expressed in different Gram-negative bacteria, is a versatile enzyme capable of hydrolyzing β-lactam rings containing antibiotics such as penicillins, cephalosporins, and even carbapenems. Multidrug resistance in bacteria mediated by NDM-1 is an emerging threat to the public health, with an enormous economic burden. There is a scarcity in the availability of specific NDM-1 inhibitors, and also a lag in the development of new inhibitors in pharmaceutical industries. In order to identify novel inhibitors of NDM-1, we screened a library of more than 20 million compounds, available at the MCULE purchasable database. Virtual screening led to the identification of six potential inhibitors, namely, MCULE-1996250788-0-2, MCULE-8777613195-0-12, MCULE-2896881895-0-14, MCULE-5843881524-0-3, MCULE-4937132985-0-1, and MCULE-7157846117-0-1. Furthermore, analyses by molecular docking and ADME properties showed that MCULE-8777613195-0-12 was the most suitable inhibitor against NDM-1. An analysis of the binding pose revealed that MCULE-8777613195-0-12 formed four hydrogen bonds with the catalytic residues of NDM-1 (His120, His122, His189, and Cys208) and interacted with other key residues. Molecular dynamics simulation and principal component analysis confirmed the stability of the NDM-1 and MCULE-8777613195-0-12 complex. The in vitro enzyme kinetics showed that the catalytic efficiency (i.e., kcat/Km) of NDM-1 on various antibiotics decreased significantly in the presence of MCULE-8777613195-0-12, due to poor catalytic proficiency (kcat) and affinity (Km). The IC50 value of MCULE-8777613195-0-12 (54.2 µM) was comparable to that of a known inhibitor, i.e., D-captopril (10.3 µM). In sum, MCULE-8777613195-0-12 may serve as a scaffold to further design/develop more potent inhibitors of NDM-1 and other β-lactamases. 相似文献
100.
Faiz Ullah Sami Ullah Muhammad Farhan Ali Khan Muhammad Mustaqeem Rizwan Nasir Paracha Muhammad Fayyaz ur Rehman Fariha Kanwal Syed Shams ul Hassan Simona Bungau 《Molecules (Basel, Switzerland)》2022,27(19)
Fluorescent molecules absorb photons of specific wavelengths and emit a longer wavelength photon within nanoseconds. Recently, fluorescent materials have been widely used in the life and material sciences. Fluorescently labelled heterocyclic compounds are useful in bioanalytical applications, including in vivo imaging, high throughput screening, diagnostics, and light-emitting diodes. These compounds have various therapeutic properties, including antifungal, antitumor, antimalarial, anti-inflammatory, and analgesic activities. Different neutral fluorescent markers containing nitrogen heterocycles (quinolones, azafluoranthenes, pyrazoloquinolines, etc.) have several electrochemical, biological, and nonlinear optic applications. Photodynamic therapy (PDT), which destroys tumors and keeps normal tissues safe, works in the presence of molecular oxygen with light and a photosensitizing drugs (dye) to obtain a therapeutic effect. These compounds can potentially be effective templates for producing devices used in biological research. Blending crown compounds with fluorescent residues to create sensors has been frequently investigated. Florescent heterocyclic compounds (crown ether) increase metal solubility in non-aqueous fluids, broadening the application window. Fluorescent supramolecular polymers have widespread use in fluorescent materials, fluorescence probing, data storage, bio-imaging, drug administration, reproduction, biocatalysis, and cancer treatment. The employment of fluorophores, including organic chromophores and crown ethers, which have high selectivity, sensitivity, and stability constants, opens up new avenues for research. Fluorescent organic compounds are gaining importance in the biological world daily because of their diverse functionality with remarkable structural features and positive properties in the fields of medicine, photochemistry, and spectroscopy. 相似文献