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41.
Multiple sclerosis is a chronic autoimmune disorder that leads to the demyelination of nerve fibers, which is the major cause of non-traumatic disability all around the world. Herbal plants Nepeta hindustana L., Vitex negundo L., and Argemone albiflora L., in addition to anti-inflammatory and anti-oxidative effects, have shown great potential as neuroprotective agents. The study was aimed to develop a neuroprotective model to study the effectiveness of herbal plants (N. hindustana, V. negundo, and A. albiflora) against multiple sclerosis. The in vivo neuroprotective effects of ethanolic extracts isolated from N. hindustana, V. negundo, and A. albiflora were evaluated in lipopolysaccharides (LPS) induced multiple sclerosis Wistar rat model. The rat models were categorized into seven groups including group A as normal, B as LPS induced diseased group, while C, D, E, F, and G were designed as treatment groups. Histopathological evaluation and biochemical markers including stress and inflammatory (MMP-6, MDA, TNF-α, AOPPs, AGEs, NO, IL-17 and IL-2), antioxidant (SOD, GSH, CAT, GPx), DNA damage (Isop-2α, 8OHdG) as well as molecular biomarkers (RAGE, Caspase-8, p38) along with glutamate, homocysteine, acetylcholinesterase, and myelin binding protein (MBP) were investigated. The obtained data were analyzed using SPSS version 21 and GraphPad Prism 8.0. The different extract treated groups (C, D, E, F, G) displayed a substantial neuroprotective effect regarding remyelination of axonal terminals and oligodendrocytes migration, reduced lymphocytic infiltrations, and reduced necrosis of Purkinje cells. The levels of stress, inflammatory, and DNA damage markers were observed high in the diseased group B, which were reduced after treatments with plant extracts. The antioxidant activity was significantly reduced in diseased induced group B, however, their levels were raised after treatment with plant extract. Group F (a mélange of all the extracts) showed the most significant change among all other treatment groups (C, D, E, G). The communal dose of selected plant extracts regulates neurodegeneration at the cellular level resulting in restoration and remyelination of axonal neurons. Moreover, 400 mg/kg dose of three plants in conjugation (Group F) were found to be more effective in restoring the normal activities of all measured parameters than independent doses (Group C, D, E) and is comparable with standard drug nimodipine (Group G) clinically used for the treatment of multiple sclerosis. The present study, for the first time, reported the clinical evidence of N. hindustana, V. negundo, and A. albiflora against multiple sclerosis and concludes that all three plants showed remyelination as well neuroprotective effects which may be used as a potential natural neurotherapeutic agent against multiple sclerosis.  相似文献   
42.
Bionanotechnology is a branch of science that has revolutionized modern science and technology. Nanomaterials, especially noble metals, have attracted researchers due to their size and application in different branches of sciences that benefit humanity. Metal nanoparticles can be synthesized using green methods, which are good for the environment, economically viable, and facilitate synthesis. Due to their size and form, gold nanoparticles have become significant. Plant materials are of particular interest in the synthesis and manufacture of theranostic gold nanoparticles (NPs), which have been generated using various materials. On the other hand, chemically produced nanoparticles have several drawbacks in terms of cost, toxicity, and effectiveness. A plant-mediated integration of metallic nanoparticles has been developed in the field of nanotechnology to overcome the drawbacks of traditional synthesis, such as physical and synthetic strategies. Nanomaterials′ tunable features make them sophisticated tools in the biomedical platform, especially for developing new diagnostics and therapeutics for malignancy, neurodegenerative, and other chronic disorders. Therefore, this review outlines the theranostic approach, the different plant materials utilized in theranostic applications, and future directions based on current breakthroughs in these fields.  相似文献   
43.
Engineered nanoparticles that have distinctive targeted characteristics with high potency are modernistic technological innovations. In the modern era of research, nanotechnology has assumed critical importance due to its vast applications in all fields of science. Biologically synthesized nanoparticles using plants are an alternative to conventional methods. In the present study, Citrullus colocynthis (bitter apple) was used for the synthesis of gold nanoparticles (AuNPs). UV-Vis’s spectroscopy, XRD, SEM and FTIR were performed to confirm the formation of AuNPs. UV-Vis’s spectra showed a characteristic peak at the range of 531.5–541.5 nm. XRD peaks at 2 θ = 38°, 44°, 64° and 77°, corresponding to 111, 200, 220 and 311 planes, confirmed the crystalline nature of AuNPs. Spherical AuNPs ranged mostly between 7 and 33 nm, and were measured using SEM. The FTIR analysis confirmed the presence of phytochemicals on the surface of AuNPs. Successful synthesis of AuNPs by seed extract of Citrullus colocynthis (bitter apple) as a capping and reducing agent represents the novelty of the present study.  相似文献   
44.
In the literature, greener analytical approaches for determining thymol in its commercial formulations, plant-based phytopharmaceuticals, and biological fluids are scarce. As a result, the goal of this study is to develop and validate a normal-phase “high-performance thin-layer chromatography (HPTLC)” method for determining thymol in commercial formulations, essential oils, traditional extracts (TE), and ultrasound-based extracts (UBE) of Thymus vulgaris and Origanum vulgare obtained from various geographical regions. The greener mobile phase for thymol analysis was a binary combination of cyclohexane and ethyl acetate (85:15, v/v). The derivatized densitometric analysis of thymol was carried out under visible mode at 530 nm utilizing anisaldehyde-sulfuric acid as a derivatizing/visualizing agent. In the 10–2000 ng/band range, the greener normal-phase HPTLC method was linear. Furthermore, for thymol analysis, the proposed analytical approach was simple, quick, inexpensive, accurate, precise, robust, sensitive, and greener. The thymol contents in commercial formulation were computed as 7.61% w/w. In general, the thymol contents were maximum in essential oils of T. vulgaris and O. vulgare compared to the other sample matrices studied. The thymol contents of TE of T. vulgaris and O. vulgare of different geographical regions were significantly low compared to their UBE extract. Using 12 distinct components of green analytical chemistry, the overall “analytical GREEnness (AGREE)” scale for the proposed analytical approach was computed 0.79, showing the good greener nature of the proposed analytical approach. Overall, the greener normal-phase HPTLC technique was found to be reliable for determining thymol in commercial formulations and plant-based phytopharmaceuticals.  相似文献   
45.
Crystals obtained in the course of preparing the tris-Schiff base iron(II) complex from 2-acetylpyridine and benzylamine have been shown by an X-ray diffraction structure determination to contain an iron(II) complex cation containing two molecules of the target Schiff base and one molecule of 2-acetylpyridine coordinated to the metal. The mechanistic implications of this fact are discussed.  相似文献   
46.
Cardiac and hepatotoxicities are major concerns in the development of new drugs. Better alternatives to other treatments are being sought to protect these vital organs from the toxicities of these pharmaceuticals. In this regard, a preclinical study is designed to investigate the histopathological effects of a new succinimide derivative (Comp-1) on myocardial and liver tissues, and the biochemical effects on selected cardiac biomarkers, hepatic enzymes, and lipid profiles. For this, an initially lethal/toxic dose was determined, followed by a grouping of selected albino rats into five groups (each group had n = 6). The control group received daily oral saline for 8 days. The 5-FU (5-Fluorouracil) group received oral saline daily for 8 days, added with the administration of a single dose of 5-FU (150 mg/kg I.P.) on day 5 of the study. The atenolol group received oral atenolol (20 mg/kg) for 8 days and 5-FU (150 mg/kg I.P.) on day 5 of the protocol. Similarly, two groups of rats treated with test compound (Comp-1) were administered with 5 mg/kg I.P. and 10 mg/kg I.P. for 8 days, followed by 5-FU (150 mg/kg I.P.) on day 5. Toxicity induced by 5-FU was manifested by increases in the serum creatinine kinase myocardial band (CK-MB), troponin I (cTnI) and lactate dehydrogenase (LDH), lipid profile, and selected liver enzymes, including ALP (alkaline phosphatase), ALT (alanine transaminase), AST (aspartate aminotransferase), BT (bilirubin total), and BD (direct bilirubin). These biomarkers were highly significantly decreased after the administration of the mentioned doses of the test compound (5 mg/kg and 10 mg/kg). Similarly, histological examination revealed cardiac and hepatic tissue toxicity by 5-FU. However, those toxic effects were also significantly recovered/improved after the administration of Comp-1 at the said doses. This derivative showed dose-dependent effects and was most effective at a dose of 10 mg/kg body weight. Binding energy data computed via docking simulations revealed that our compound interacts toward the human beta2-adrenergic G protein-coupled receptor (S = −7.89 kcal/mol) with a slight stronger affinity than the calcium channel T-type (S = −7.07 kcal/mol). In conclusion, the histological and biochemical results showed that the test compound (Comp-1) had prominent cardioprotective, hepatoprotective, and lipolytic effects against 5-FU-induced toxicity in the subjected animal model.  相似文献   
47.
Optics and Spectroscopy - We present differential nonlinear absorption of an elliptically polarized femtosecond laser vortex beam carrying an angular momentum of $$\ell = - 1$$ in tellurite glass....  相似文献   
48.
Optics and Spectroscopy - Optical solitons with fiber Bragg gratings and polynomial law of nonlinear refractive index are addressed in the paper. The auxiliary equation approach together with an...  相似文献   
49.
Cobalt sulfide/sulfur doped carbon composites (Co9S8/S‐C) were synthesized by calcining a rationally designed sulfur‐containing cobalt coordination complex in an inert atmosphere. From the detailed transmission electron microscopy (TEM) and X‐ray photoelectron spectroscopy (XPS) analyses, the electrocatalytically active Co9S8 nanoparticles were clearly obtained and combined with the thin sulfur doped carbon layers. Electrochemical data showed that Co9S8/S‐C had a good activity and long‐term stability in catalyzing oxygen evolution reaction in alkaline electrolyte, even better than the traditional RuO2 electrocatalyst. The excellent electrocatalytic activity of Co9S8/S‐C was mainly attributed to the synergistic effect between the Co9S8 catalyst which contributed to the oxygen evolution reaction and the sulfur doped carbon layer which facilitated the adsorption of reactants, prevented the Co9S8 particles from aggregating and served as the electrically conductive binder between each component.  相似文献   
50.
Mesoporous iron phosphate (FePO4) was synthesized through assembly of polymeric micelles made of asymmetric triblock co‐polymer (polystyrene‐b‐poly‐2‐vinylpyridine‐b‐ethylene oxide; PS‐PVP‐PEO). The phosphoric acid solution stimulates the formation of micelles with core–shell‐corona architecture. The negatively charged PO43? ions dissolved in the solution strongly interact with the positively charged PVP+ units through an electrostatic attraction. Also, the presence of PO43? ions realizes a bridge between the micelle surface and the metal ions. The removal of polymeric template forms the robust framework of iron phosphate with 30 nm pore diameter and 15 nm wall thickness. Our method is applicable to other mesoporous metal phosphates by changing metal sources. The obtained materials were fully characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), N2 adsorption–desorption, Raman spectroscope, and other techniques.  相似文献   
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