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A novel approach is unveiled for the expedited synthesis of valuable α-substituted ketones, utilising aliphatic amine catalysis to drive the oxidative C-O/C-N coupling reaction between alkynes and an appropriate nucleophile. This one-pot synthesis employs hypervalent iodine as both the oxidant and coupling agent. A fast, metal-free, and environmentally benign method is developed for synthesising α-acetoxyketones and α-imidoketones in an aqueous medium. To demonstrate the potential for larger-scale production, a gram-scale reaction is conducted. Moreover, the newly developed methodology has successfully enabled the direct synthesis of cathinone, a psychoactive drug. Overall, this work holds significant promise for the efficient and sustainable synthesis of α-substituted ketones and the potential development of novel biologically active compounds.
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The discovery that all cells secrete extracellular vesicles (EVs) to shuttle proteins and nucleic acids to recipient cells suggested they play an important role in intercellular communication. EVs are widely distributed in many body fluids, including blood, cerebrospinal fluid, urine and saliva. Exosomes are nano-sized EVs of endosomal origin that regulate many pathophysiological processes including immune responses, inflammation, tumour growth, and infection. Healthy individuals release exosomes with a cargo of different RNA, DNA, and protein contents into the circulation, which can be measured non-invasively as biomarkers of healthy and diseased states. Cancer-derived exosomes carry a unique set of DNA, RNA, protein and lipid reflecting the stage of tumour progression, and may serve as diagnostic and prognostic biomarkers for various cancers. However, many gaps in knowledge and technical challenges in EVs and extracellular RNA (exRNA) biology, such as mechanisms of EV biogenesis and uptake, exRNA cargo selection, and exRNA detection remain. The NIH Common Fund-supported exRNA Communication Consortium was launched in 2013 to address major scientific challenges in this field. This review focuses on scientific highlights in biomarker discovery of exosome-based exRNA in cancer and its possible clinical application as cancer biomarkers.
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The present study delves into the interaction of a potent cancer-cell photosensitizer Norharmane (NHM) with non-ionic triblock copolymer P123, followed by the assessment of the stability of the formed complex in the presence of ß-cyclodextrin (ß-CD). Spectroscopic results unveil the modulation of the prototropic equilibrium of NHM within the constrained microheterogeneous medium of the copolymer micelle to be favoured towards the neutral species of NHM over the cationic counterpart; which has been aptly rationalized invoking the key role of hydrophobic interaction in the association process and is further reinforced from steady-state and time-resolved spectroscopic measurements. The micropolarity of the probe-binding site has been evaluated by the archetypal ET(30) analysis revealing that the cationic probe remains in the corona region of the micelle instead of penetrating deeper into the micellar core. Moreover, the effect of ß-CD on the stability of the NHM-bound P123 aggregates has also been investigated, revealing that ß-CD can be used as a potential host for the release of the micelle-encapsulated drug through an inclusion complex formation with the P123 monomers. The result is expected to be of potential interest from medical perspective owing to the context of efficient drug release at their potential sites.
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Antineoplásicos , Micelas , Fármacos Fotosensibilizantes , beta-Ciclodextrinas/química , Antineoplásicos/análisis , Antineoplásicos/química , Antineoplásicos/farmacocinética , Liberación de Fármacos , Modelos Moleculares , Fármacos Fotosensibilizantes/análisis , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacocinética , Espectrometría de FluorescenciaRESUMEN
PURPOSE OF REVIEW: There has been an increasing interest in using complementary and alternative medicine (CAM) approaches to treat cancer. It is therefore relevant and timely to determine if CAM biomarkers can be identified and developed to guide cancer diagnosis and treatment. Herein, we review the status of cancer biomarkers in CAM research and treatment to stimulate further research in this area. RECENT FINDINGS: Studies on promising anti-cancer natural products, such as PHY906, honokiol, bryostatin-1, and sulforaphane have demonstrated the existence of potential cancer biomarker(s). Additional studies are required to further develop and ultimately validate these biomarkers that can predict clinical activity of the anti-cancer natural products used alone or in combination with chemotherapeutic agents. A systematic approach is needed to identify and develop CAM treatment associated biomarkers and to define their role in facilitating clinical decision-making. The expectation is to use these biomarkers in determining potential options for CAM treatment, examining treatment effects and toxicity and/or clinical efficacy in patients with cancer.
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Productos Biológicos/uso terapéutico , Biomarcadores de Tumor/metabolismo , Terapias Complementarias/estadística & datos numéricos , Medicina Integrativa , Medicina Tradicional/estadística & datos numéricos , Neoplasias/patología , Terapias Complementarias/métodos , Humanos , Oncología Médica , Medicina Tradicional/métodos , Neoplasias/metabolismo , Neoplasias/terapiaRESUMEN
The discrete effects of a series of structurally divergent monomeric viz. Sodium Chloride (NaCl), Tetra-butyl Ammonium Chloride (TBAC) and Sodium Benzoate (NaBz) and polymeric viz. Sodium Polystyrene Sulfonate (NaPSS) electrolytes towards the morphological and/or aggregation properties of Octadecyl-trimethyl Ammonium Bromide (OTAB) micelles have been quantified spectroscopically by means of the modulations of the absorption and emission spectral properties of an extrinsic anthracene-based probe 9-methyl anthroate (9-MA) within the concerned media. Further corroboration of the spectroscopic results was acquired from the non-invasive dynamic light scattering technique. The qualitatively similar mode of action of all the monomeric salts has been explained on the basis of the archetypal Israelachvili model whereas the corresponding extent of the morphological transition of the micelles, which is found to follow the order NaBz > NaCl > TBAC, has been explained invoking the co-sphere overlap model. Conversely, to explain the aggregation behaviour of the micelles in the presence of the polymeric electrolyte, a two-step model has been formulated. According to this model, at the low concentration regime, the polymeric salt is found to only neutralize the surface charge of the micelles inducing micellar growth; whereas further increment in the concentration of the polymer assists the hydrophobic association between the micelles leading to the formation of larger aggregates, eventually causing a phase separation.
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Electrólitos/química , Transición de Fase , Polímeros/química , Tensoactivos/química , Alcanos/química , Anisotropía , Antracenos/química , Cationes , Dispersión Dinámica de Luz , Micelas , Tamaño de la Partícula , Poliestirenos/química , Compuestos de Amonio Cuaternario/química , Espectrometría de FluorescenciaRESUMEN
Therapies originating from traditional medical systems are widely used by patients in both India and the United States. The first India-US Workshop on Traditional Medicine was held in New Delhi, India, on March 3 and 4, 2016, as a collaboration between the Ministry of Ayurveda, Yoga and Naturopathy, Unani, Siddha, and Homoeopathy (AYUSH) of the Government of India, the US National Cancer Institute (NCI), National Institutes of Health, and the Office of Global Affairs, US Department of Health and Human Services. It was attended by Indian and US policymakers, scientists, academics, and medical practitioners from various disciplines. The workshop provided an opportunity to open a dialogue between AYUSH and NCI to identify promising research results and potential topics for Indo-US collaboration. Recommendations that emerged from the workshop underlined the importance of applying rational and scientific approaches for drug development; standardizing traditional medicine products and procedures to ensure reliability and reproducibility; promotion of collaboration between Indian traditional medicine practitioners and researchers and US researchers; greater integration of evidence-based traditional medicine practices with mainstream medical practices in India; and development of training programs between AYUSH and NCI to facilitate crosstraining. Several positive developments took place after the thought-provoking deliberations.
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Medicina Basada en la Evidencia , Medicina Tradicional , Investigación , Desarrollo de Medicamentos , Educación Médica , Humanos , India , Medicina Tradicional/métodos , Neoplasias/terapia , Estados UnidosRESUMEN
The prime motivation of the present study is to explore the effect of reverse micellar confinement on the binding interaction of an anthracene-based probe 9-methyl anthroate with herring-sperm DNA. The structural modification of the genomic DNA from its native B-form to the non-native C-form and subsequently to the condensed Ψ-form as a function of the level of hydration (W0, defined as [water]â¯/â¯[surfactant]) of the reverse micellar core is found to reveal a remarkable regulatory role on the stability of the stacking interaction (intercalation) of the probe within the DNA helix; the interaction being progressively stabilized at higher W0. Particularly, a close perusal of the dynamical aspects of the interaction is found to be counter-intuitive to the popular notion of the properties of the confined water within the reverse micelles typically approaching bulk-like properties at sufficiently high hydration levels (W0â¯>â¯10).
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Sondas de ADN/química , ADN Forma B/química , ADN de Forma C/química , Micelas , Agua/químicaRESUMEN
The crucial role of chemosensor for the immediate recognition of environment pollutant motivates the researchers to develop variety of sensing protocols. Of various chemosensory protocols, the colour change observed by the naked eye is considered to be a conceivable and on-site way to indicate the presence of an analyte. We herein report a colourimetric and commercially available absorption probe, sinapic acid (SA) that is completely ready to use for "on-site" visual determination of copper ions. The molecule, SA is well-known phenolic acid, often utilized for its antibacterial activity. In this work, for the first time, we are exploring its ability to work as an efficient Cu2+ sensor. This sensor molecule selectively detected Cu2+ ions by changing its colour from colourless to pink within detection limit of 64.5nM, which is much lower than other reported sensor molecules and the suggested limit by World Health Organization (WHO) and U. S. Environmental Protection Agency (EPA) guidelines. The sensing mechanism was investigated through UV-vis and 1H NMR titration along with ESI-MS spectroscopy and further confirmed by DFT computational studies. Studies revealed the participation of hydroxyl group (OH) and methoxy group (OMe) of SA in complexation with Cu2+. The binding stoichiometry of SA to Cu2+ was found to be 1:2 through Job's plot and ESI-MS analysis. Importantly, paper strips of SA were prepared which could be used for a rapid "on-site" determination of Cu2+ containing samples.
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Two amido-schiff bases (3-Hydroxy-naphthalene-2-carboxylic acid pyren-1-ylmethylene-hydrazide and Naphthalene-2-carboxylic acid pyren-1-ylmethylene-hydrazide) have been synthesized having a common structural unit and only differs by a -OH group in the naphthalene ring. Both of them can detect Cu2+ ion selectively in semi-aqueous medium in distinctly different output modes (one detects Cu2+ by naked-eye color change where as the other detects Cu2+ by fluorescence enhancement). The difference in the binding of Cu 2+ with the compounds is the reason for this observation. The detection limit is found to be micromolar region for compound which contains -OH group whereas the compound without -OH group detects copper in nano-molar region. DFT calculations have been performed in order to demonstrate the structure of the compounds and their copper complexes. Practical utility has been explored by successful paper strip response of both the compounds. The biological applications have been evaluated in RAW 264.7.
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Cobre/análisis , Modelos Moleculares , Bases de Schiff/química , Animales , Cationes , Color , Cinética , Ratones , Microscopía Fluorescente , Conformación Molecular , Teoría Cuántica , Células RAW 264.7 , Bases de Schiff/síntesis química , Espectrometría de Fluorescencia , Espectrofotometría UltravioletaRESUMEN
Cancer therapies can provide substantially improved survival in some patients while other seemingly similar patients receive little or no benefit. Strategies to identify patients likely to respond well to a given therapy could significantly improve health care outcomes by maximizing clinical benefits while reducing toxicities and adverse effects. Using a glycan microarray assay, we recently reported that pretreatment serum levels of IgM specific to blood group A trisaccharide (BG-Atri) correlate positively with overall survival of cancer patients on PROSTVAC-VF therapy. The results suggested anti-BG-Atri IgM measured prior to treatment could serve as a biomarker for identifying patients likely to benefit from PROSTVAC-VF. For continued development and clinical application of serum IgM specific to BG-Atri as a predictive biomarker, a clinical assay was needed. In this study, we developed and validated a Luminex-based clinical assay for measuring serum IgM specific to BG-Atri. IgM levels were measured with the Luminex assay and compared to levels measured using the microarray for 126 healthy individuals and 77 prostate cancer patients. This assay provided reproducible and consistent results with low %CVs, and tolerance ranges were established for the assay. IgM levels measured using the Luminex assay were found to be highly correlated to the microarray results with R values of 0.93-0.95. This assay is a Laboratory Developed Test (LDT) and is suitable for evaluating thousands of serum samples in CLIA certified laboratories that have validated the assay. In addition, the study demonstrates that discoveries made using neoglycoprotein-based microarrays can be readily migrated to a clinical assay.
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Vacunas contra el Cáncer/uso terapéutico , Inmunoglobulina M/sangre , Pruebas Inmunológicas/métodos , Oligosacáridos/inmunología , Neoplasias de la Próstata/terapia , Sistema del Grupo Sanguíneo ABO , Biomarcadores/metabolismo , Humanos , Masculino , Oligosacáridos de Cadena Ramificada , Polisacáridos/metabolismo , Neoplasias de la Próstata/inmunología , Análisis por Matrices de Proteínas , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
The amido-Schiff base 1 (N1, N3-bis (2-nitrobenzylidene)benzene-1,3-dicabohydrazide) containing a CONH group and CHN linkage has been synthesized by the condensation between isophthalic acid dihydrazide and o-nitrobenzaldehyde. This molecule can act as a fluoride ion sensor with high selectivity and sensitivity. Presence of nitro group in the phenyl ring may be responsible for the detection of fluoride ion visually with a dramatic color change from colorless to deep red in aqueous dimethyl sulphoxide solution. This Schiff base can be used as test kit for sensing of fluoride ion in the solid state. Compound 1 can detect fluoride also in commercially available toothpaste. As the compound has adequate solubility in DMSO-water mixture (7:93, v/v) and having some hydrogen bond donor and acceptor centers, we have investigated its nature of binding with Calf Thymus-DNA (CT-DNA) using theoretical molecular modelling and other experimental methods like UV-vis spectroscopy, circular dichroic and thermal melting studies. Thermodynamic parameters have been obtained using the well known Van't Hoff's equation. From both theoretical and experimental findings it has been observed that it can interact effectively with CT-DNA with binding energy -7.55kcal/mol to -7.50kcal/mol.
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Colorimetría/métodos , ADN/metabolismo , Fluoruros/análisis , Bases de Schiff/metabolismo , Animales , Aniones/análisis , Bovinos , Dicroismo Circular , Color , Conformación Molecular , Simulación del Acoplamiento Molecular , Desnaturalización de Ácido Nucleico , Espectroscopía de Protones por Resonancia Magnética , Bases de Schiff/síntesis química , Bases de Schiff/química , Espectrofotometría Ultravioleta , Termodinámica , Pastas de Dientes/químicaRESUMEN
The present work demonstrates a detailed photophysics of bio-active drug-like acid viz., 2-hydroxynicotinic acid (2-HNA) and its interaction with a model plasma protein Bovine Serum Albumin (BSA). The drug which is in essence a vitamin-B3 derivative, is capable of exhibiting ultrafast lactim-lactam cross-over response and thereby the modulation of the lactam emission within the bio-environment of the protein has been depicted spectroscopically to reveal the drug-protein interaction. Apart from evaluating the binding constant, the probable location of the neutral drug molecule within the protein cavity (hydrophobic subdomain IIIA) has been explored by AutoDock-based blind docking simulation technique. In this microheterogeneous medium, slow solvent reorientation time with respect to the emissive lifetime of the drug explicate the Red Edge Effect (REE). To complement the findings about the binding process, chaotrope-induced protein denaturation has also been inspected. The probe also illustrates a perceptible difference in rotational relaxation time in confined medium than in aqueous medium which strengthen our verdict. Unfolding of the protein in the presence of the drug molecule has been probed by the decrease of the α-helical content, obtained via circular dichroism (CD) spectroscopy, which is also supported by the gradual slaughter of the esterase activity of the protein in the presence of the drug molecule.
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Proteínas Sanguíneas/química , Niacina/química , Unión Proteica , Conformación Proteica , Espectrometría de FluorescenciaRESUMEN
A pyrene containing chemosensor viz. has been designed for the efficient and selective detection of Cu(2+) and F(-) ions in dual sensing mode which do not interfere with each other. The chemosensing behavior of towards Cu(2+) was demonstrated through fluorescence, time resolved fluorescence spectroscopy, and visual fluorescence colour changes, and towards F(-) through naked-eye colour changes, absorption and (1)H NMR titrations. The chemosensor shows excellent selectivity towards Cu(2+) through an excimer switch-off mechanism. Density Functional Theory (DFT) calculations were performed to show the structure and electronic properties of and its copper complex [-Cu(2+)]. The selectivity and sensitivity towards F(-) were explained in terms of H-bonding interactions between and F(-), then deprotonation of . The biological application of has been evaluated in HEK 293 cells and it exhibits good membrane permeability for the detection of Cu(2+). The sensor also shows appreciable sensitivity towards fluoride in toothpaste.
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In this paper, the binding interaction of a promising chloride channel blocker, 9-methyl anthroate (9-MA), with two different classes of molecular containers, ß-cyclodextrins (ß-CD and methyl-ß-CD) and cucurbit[7]uril, having comparable cavity dimensions, has been thoroughly demonstrated via inspection of the modulation of the excited-state properties of the emissive molecule. Spectral data suggest that CB7 encapsulates the probe more efficiently in a 1:2 fashion, whereas the efficacies of ß-CDs are relatively less and the corresponding stoichiometry is 1:1. Interestingly, despite being thermodynamically much more favorable than the probe-ß-CD complexation equilibria, the fraction of probe-CB7 complex formed is appreciably smaller with respect to that of probe-ß-CD complexes. This apparent inconsistency has been addressed via the proposition that since the formation of a 1:2 complex is entropically disadvantageous, it is anticipated that the activation barrier of the corresponding reaction is reasonably high, and thus only a small fraction of the reactants are able to surpass the energy barrier to form the products. This proposition has been thoroughly corroborated by fluorescence lifetime measurements at different temperatures.
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In this article, the binding interactions of a promising chloride channel blocker 9-methyl anthroate (9-MA) with a series of bile-salt aggregates of varying hydrophobicity have been thoroughly demonstrated. The altered photophysical properties of the fluorescent probe within the concerned microheterogeneous environments have been exploited spectroscopically to assess the communication between the aggregates and the guest. The contrived hydrophobic environment provided by the aggregates appreciably diminishes the water-assisted non-radiative decay channels and thus extends the fluorescence lifetime and the rotational relaxation time of the probe. NaDC aggregates, being more rigid and hydrophobic, provide a better protection to the bound guest from the external influence which is apparent from a much longer fluorescence lifetime and rotational correlation time for the encapsulated probe in NaDC aggregates compared to those in NaC and NaTC aggregates, as is further validated by fluorescence quenching experiments. Salt induced alterations of the binding behavior of the probe with the bile-salt aggregates have also been evaluated via fluorimetric studies, which conclude larger and tighter aggregate formation resulting in a superior degree of rigidity imposed on the aggregate-bound probe at high ionic strength of the medium.
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Antracenos/química , Ácidos y Sales Biliares/química , Canales de Cloruro/antagonistas & inhibidores , Colorantes Fluorescentes/química , Fluorescencia , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Concentración Osmolar , Espectrometría de FluorescenciaRESUMEN
The Extracellular RNA (exRNA) Communication Consortium, funded as an initiative of the NIH Common Fund, represents a consortium of investigators assembled to address the critical issues in the exRNA research arena. The overarching goal is to generate a multi-component community resource for sharing fundamental scientific discoveries, protocols, and innovative tools and technologies. The key initiatives include (a) generating a reference catalogue of exRNAs present in body fluids of normal healthy individuals that would facilitate disease diagnosis and therapies, (b) defining the fundamental principles of exRNA biogenesis, distribution, uptake, and function, as well as development of molecular tools, technologies, and imaging modalities to enable these studies,
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Studies on the interaction of naturally occurring flavonoids with different polymorphic forms of nucleic acid are helpful for understanding the molecular aspects of binding mode and providing direction for the use and design of new efficient therapeutic agents. However, much less information is available on the interactions of these compounds with different polymorphic forms of DNA at the molecular level. In this report we investigated the interaction of two widely abundant dietary flavonoids quercetin (Q) and morin (M) with calf thymus (CT) DNA. Spectrophotometric, spectropolarimetric, viscosity measurement, and molecular docking simulation methods are used as tools to delineate the binding mode and probable location of the flavonoids and their effects on the stability and conformation of DNA. It is observed that in the presence of the protonated form of DNA the dual fluorescence of Q and M resulting from the excited-state intramolecular proton transfer (ESIPT) is modified significantly. Structural analysis showed Q and M binds weakly to the B form (groove binding) compared to the protonated form of CT DNA (electrostatic interaction). In both cases, Q binds strongly to both forms of DNA compared to M.
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ADN Forma B/química , ADN/química , Flavonoides/química , Quercetina/química , Animales , Anisotropía , Bovinos , Concentración de Iones de Hidrógeno , Radical Hidroxilo/química , Modelos Químicos , Modelos Genéticos , Simulación del Acoplamiento Molecular , Estructura Molecular , Conformación de Ácido Nucleico , Protones , Análisis Espectral , ViscosidadRESUMEN
A series of Schiff bases synthesized by the condensation of benzohydrazide and -NO2 substituted benzaldehyde have been used as selective fluoride ion sensor. Test paper coated with these synthetic Schiff bases (test kits) can detect fluoride ion selectively with a drastic color change and detection can be achieved by just using the naked-eye without the help of any optical instrument. Interestingly, the position of -NO2 group in the amido Schiff bases has an effect on the sensitivity as well as on the change of color of species.
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Amidas/química , Colorimetría/métodos , Fluoruros/análisis , Nitrocompuestos/química , Bases de Schiff/química , Acetonitrilos/química , Aniones , Color , Cinética , Espectroscopía de Protones por Resonancia Magnética , Solventes , Espectrofotometría UltravioletaRESUMEN
A simple Schiff base compound 2-((cyclohexylmethylimino)-methyl)-naphthalen-1-ol (2CMIMN1O) has been synthesized and characterized by (1)H NMR, (13)C NMR and FT-IR spectroscopic techniques. A significantly low emission yield of the compound has been rationalized in anticipation with photo-induced electron transfer (PET) from the imine receptor moiety to the naphthalene fluorophore unit. Consequently, an evaluation of the transition metal ion-induced modification of the fluorophore-receptor communication reveals the promising prospect of the title compound to function as a chemosensor for Cu(2+) and Zn(2+) ions selectively, through remarkable fluorescence enhancement as well as visual changes. While perturbation of the PET process has been argued to be the plausible mechanism behind the fluorescence enhancement, the selectivity for these two metal ions has been interpreted on the grounds of an appreciably strong binding interaction. Particularly notable aspects regarding the chemosensory activity of the compound is its ability to detect the aforesaid transition metal ions down to the level of micromolar concentration (detection limit being 2.74 and 2.27ppm respectively), along with a simple and efficient synthetic procedure.