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41.
Shilpa Raina Vikas Sharma Zahid Nabi Sheikh Navneet Kour Shashank K. Singh Ali Zari Talal A. Zari Hesham F. Alharby Khalid Rehman Hakeem 《Molecules (Basel, Switzerland)》2022,27(7)
The current study was conducted to examine the in vitro anticancer potential of Cordia dichotoma (bark, leaves, pulp and seed). The plant material was collected from UT of J&K and methodical bioassays were carried out on ten human cancer cell lines (Michigan Cancer Foundation-7 (MCF-7), M.D. Anderson-Metastatic Breast (MDA-MB-231), Neuroblastoma-2a (N2A), SH-SY5Y, U-251, HCT-116, SW-620, A-549, MIA PaCa-2, Panc-1) from five different origins (breast, CNS, colon, lung, pancreas) respectively. Methanolic extracts were produced and fractions were then obtained from the extracts and evaluated for cytotoxicity. Mechanistic assays, HPLC, and GCMS profiling were performed on the highest active fraction. The Sulforhodamine B (SRB) assay determined the in vitro cytotoxicity. The findings revealed that the bark portion had in vitro cytotoxicity against the A-549 human lung cancer cell line. To our knowledge, this is the first study to show that the plant’s bark has anticancer properties and induced chromatin condensation, confirmed cell death via ROS generation, and significantly decreased colony formation in A-549 cell line from lung origin in a dose-dependent manner. Furthermore, HPLC and GCMS investigations indicated the presence of a number of bioactive molecules such as gallic acid (144,969.86) uV*sec, caffeic acid (104.26) uV*sec, ferulic acid (472.87) uV*sec, vanillic acid (13,775.39) uV*sec, palmitic acid (18.34%), cis vaccenic acid (28.81%), etc. and one of the compounds was reported for the first time from the bark. As a result of its promising efficacy, it may become an essential cancer chemopreventive or chemotherapeutic medication for patients with lung carcinoma. 相似文献
42.
Ana Maria Pereira Ayse Kaya Dan Alves Niusha Ansari-Fard Ibrahim Tolaymat Basel Arafat Mohammad Najlah 《Molecules (Basel, Switzerland)》2022,27(17)
Disulfiram (DS), known as an anti-alcoholism drug, has shown a potent antiviral activity. Still, the potential clinical application of DS is limited by its low water solubility and rapid metabolism. Cyclodextrins (CDs) have been widely used to improve the solubility of drugs in water. In this study, five concentrations of hydroxypropyl β-cyclodextrin (HP) and sulfobutyl ether β-cyclodextrin (SBE) were used to form inclusion complexes of DS for enhanced solubility. Solutions were freeze-dried, and the interaction between DS and CD was characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). In addition, the nebulization properties of the DS–CD solutions were studied. The aqueous solubility of DS increased significantly when loaded to either of both CDs. The phase solubility of both complexes was a linear function of the CD concentration (AL type). Furthermore, physicochemical characterization studies showed a potent inclusion of the drug in the CD–DS complexes. Aerosolization studies demonstrated that these formulations are suitable for inhalation. Overall, the CD inclusion complexes have great potential for the enhancement of DS solubility. However, further studies are needed to assess the efficacy of DS–CD inclusion complexes against SARS-CoV-2 via nebulization. 相似文献
43.
Essmat M. El-Sheref Mohamed A. Ameen Kamal M. El-Shaieb Fathy F. Abdel-Latif Asmaa I. Abdel-naser Alan B. Brown Stefan Brse Hazem M. Fathy Iqrar Ahmad Harun Patel Hesham A. M. Gomaa Bahaa G. M. Youssif Asmaa H. Mohamed 《Molecules (Basel, Switzerland)》2022,27(24)
Our investigation includes the synthesis of new naphthalene-bis-triazole-bis-quinolin-2(1H)-ones 4a–e and 7a–e via Cu-catalyzed [3 + 2] cycloadditions of 4-azidoquinolin-2(1H)-ones 3a–e with 1,5-/or 1,8-bis(prop-2-yn-1-yloxy)naphthalene (2) or (6). All structures of the obtained products have been confirmed with different spectroscopic analyses. Additionally, a mild and versatile method based on copper-catalyzed [3 + 2] cycloaddition (Meldal–Sharpless reaction) was developed to tether quinolinones to O-atoms of 1,5- or 1,8-dinaphthols. The triazolo linkers could be considered as anti and syn products, which are interesting precursors for functionalized epidermal growth factor receptor (EGFR) inhibitors with potential apoptotic antiproliferative action. The antiproliferative activities of the 4a–e and 7a–e were evaluated. Compounds 4a–e and 7a–e demonstrated strong antiproliferative activity against the four tested cancer cell lines, with mean GI50 ranging from 34 nM to 134 nM compared to the reference erlotinib, which had a GI50 of 33 nM. The most potent derivatives as antiproliferative agents, compounds 4a, 4b, and 7d, were investigated for their efficacy as EGFR inhibitors, with IC50 values ranging from 64 nM to 97 nM. Compounds 4a, 4b, and 7d demonstrated potent apoptotic effects via their effects on caspases 3, 8, 9, Cytochrome C, Bax, and Bcl2. Finally, docking studies show the relevance of the free amino group of the quinoline moiety for antiproliferative action via hydrogen bond formation with essential amino acids. 相似文献
44.
Hesham A. Elkaranshawy Khaled T. Mohamed Ahmed S. Ashour Hassan M. Alkomy 《Nonlinear dynamics》2017,88(3):1691-1705
For a rigid body or a multibody system sliding on a rough surface, a range of uncertainty or non-uniqueness of solution could be found, which is termed: Painlevé paradox. Painlevé paradox is the reason of a wide range of undesired bouncing motions which are observed during sliding. As Painlevé paradox is a practical problem in case of multibody systems, this research work has investigated that paradox. In this research work, the condition leading to Painlevé paradox has been determined for a general multibody system. Investigating the motion of a prismatic–revolute (P–R), sliding robot has been conducted. In order to solve the paradox and find the motion, a tangential impact is assumed at the contact point. The impact model has been developed and the paradox, consequently, has been solved. Consequently, the kinematics of the motion has been specified. 相似文献
45.
The methanolic extract of Languas galanga rhizomes was investigated for antimalarial activity against Plasmodium berghei (NK65) infections in mice. The median lethal dose was determined to ascertain the safety of the extract in ICR mice of both sexes. The antimalarial activities during early and established infections, as well as the prophylactic activity were evaluated. Phytochemical screening and radical scavenging activity of the extract were also investigated to elucidate the possible mechanism of the antimalarial properties. The acute oral toxicity (LD??) of Languas galanga extract in mice was established to be 4.998 mg/kg. The extract of Languas galanga rhizomes demonstrated significant antiplasmodial activity in all the three models of the antimalarial evaluations. Phytochemical screening revealed the presence of some vital antiplasmodial constituents such as terpenoids and flavonoids. The extract also exhibited a moderate capacity to scavenge the free radicals. The rhizome extract of Languas galanga thus possesses antimalarial activity, which explains the rational usage of this plant in traditional Malaysian medicine. 相似文献
46.
We present a new method, link-test, to select prostate cancer biomarkers from SELDI mass spectrometry and microarray data sets. Biomarkers selected by link-test are supported by data sets from both mRNA and protein levels, and therefore results in improved robustness. Link-test determines the level of significance of the association between a microarray marker and a specific mass spectrum marker by constructing background mass spectra distributions estimated by all human protein sequences in the SWISS-PROT database. The data set consist of both microarray and mass spectrometry data from prostate cancer patients and healthy controls. A list of statistically justified prostate cancer biomarkers is reported by link-test. Cross-validation results show high prediction accuracy using the identified biomarker panel. We also employ a text-mining approach with OMIM database to validate the cancer biomarkers. The study with link-test represents one of the first cross-platform studies of cancer biomarkers. 相似文献
47.
Taha A. Hussien Tarik A. Mohamed Abdelsamed I. Elshamy Mahmoud F. Moustafa Hesham R. El-Seedi Paul W. Pare Mohamed-Elamir F. Hegazy 《Molecules (Basel, Switzerland)》2021,26(7)
Centaurothamnus maximus (family Asteraceae), is a leafy shrub indigenous to the southwestern Arabian Peninsula. With a paucity of phytochemical data on this species, we set out to chemically characterize the plant. From the aerial parts, two newly identified guaianolides were isolated: 3β-hydroxy-4α(acetoxy)-4β(hydroxymethyl)-8α-(4-hydroxy methacrylate)-1αH,5αH, 6αH-gual-10(14),11(13)-dien-6,12-olide (1) and 15-descarboxy picrolide A (2). Seven previously reported compounds were also isolated: 3β, 4α, 8α-trihydroxy-4-(hydroxymethyl)-lαH, 5αH, 6βH, 7αH-guai-10(14),11(13)-dien-6,12-olide (3), chlorohyssopifolin B (4), cynaropikrin (5), hydroxyjanerin (6), chlorojanerin (7), isorhamnetin (8), and quercetagetin-3,6-dimethyl ether-4’-O-β-d-pyranoglucoside (9). Chemical structures were elucidated using spectroscopic techniques, including High Resolution Fast Atom Bombardment Mass Spectrometry (HR-FAB-MS), 1D NMR; 1H, 13C NMR, Distortionless Enhancement by Polarization Transfer (DEPT), and 2D NMR (1H-1H COSY, HMQC, HMBC) analyses. In addition, a biosynthetic pathway for compounds 1–9 is proposed. The chemotaxonomic significance of the reported sesquiterpenoids and flavonoids considering reports from other Centaurea species is examined. 相似文献
48.
El-Askary HI 《Molecules (Basel, Switzerland)》2005,10(8):971-977
A new diacetyl triterpene lactone, drosericarpone (2), was isolated from the hexane extract of the herb Cleome droserifolia, together with buchariol (1, a sesquiterpene oxide, isolated for the first time from Cleome species) and stigmasterol glucoside (3). The structures of 1-3 were identified by spectroscopic means. 相似文献
49.
50.
Mohammad Arafat Hussain Farzana Alam Sharmin Akhtar Rupa Rayhana Awwal Soo Yeol Lee Md. Kamrul Hasan 《Ultrasonics》2014
Elasticity imaging techniques with built-in or regularization-based smoothing feature for ensuring strain continuity are not intelligent enough to prevent distortion or lesion edge blurring while smoothing. This paper proposes a novel approach with built-in lesion edge preservation technique for high quality direct average strain imaging. An edge detection scheme, typically used in diffusion filtering is modified here for lesion edge detection. Based on the extracted edge information, lesion edges are preserved by modifying the strain determining cost function in the direct-average-strain-estimation (DASE) method. The proposed algorithm demonstrates approximately 3.42–4.25 dB improvement in terms of edge-mean-square-error (EMSE) than the other reported regularized or average strain estimation techniques in finite-element-modeling (FEM) simulation with almost no sacrifice in elastographic-signal-to-noise-ratio (SNRe) and elastographic-contrast-to-noise-ratio (CNRe) metrics. The efficacy of the proposed algorithm is also tested for the experimental phantom data and in vivo breast data. The results reveal that the proposed method can generate a high quality strain image delineating the lesion edge more clearly than the other reported strain estimation techniques that have been designed to ensure strain continuity. The computational cost, however, is little higher for the proposed method than the simpler DASE and considerably higher than that of the 2D analytic minimization (AM2D) method. 相似文献