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The styrylpyrone dehydrogoniothalamin (1) and two of its dimers (2 and 3) were isolated from the leaves of Aniba heringeri (Lauraceae). Compound 3 is new, while 1 and 2 are being reported for the first time in this species. Structures were determined by 1D- and 2D-NMR spectroscopy, mass spectrometry, and optical rotation data. Cytotoxic effects and selectivity indices were evaluated in five neoplastic cell lines-PC-3 (prostate), 786-0 (renal), HT-29 (colon), MCF-7, and MDA-MB-231 (breast)-and a non-neoplastic cell line, (NIH/3T3, murine fibroblast). Compound 1 inhibited cell growth by 50% (GI 50 ) at concentrations in the 90.4-175.7 μM range, while 2 proved active against MCF-7 and MDA-MB-231 breast cells (GI 50  = 12.24, and 34.22 μM, respectively). Compound 3 showed strong cytotoxicity (GI 50  = 4.4 μM) against MDA-MB-231 (an established basal triple-negative breast carcinoma (TNBC) cell line), with a high selective index of 35. This compound was subsequently evaluated for apoptosis induction in MDA-MB-231 cells, using GI 50 and 50% lethal concentrations (LC 50 ). Flow cytometry analysis showed that at LC 50 compound 3 induced cell death with phosphatidylserine externalization and caspase-3 activation. Apoptotic genes were measured by RT-qPCR, revealing an upregulation of BAX, with an increase in expression of the BAX/BCL2 ratio in treated cells. Fluorescence microscopy disclosed morphological changes related to apoptosis. Overall, these findings showed compound 3 to be a promising prototype against TNBC cells that tend to respond poorly to conventional therapies., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Fructose-1,6-bisphosphatase (FBPase) is an attractive target for affecting the GNG pathway. In our previous study, the C128 site of FBPase has been identified as a new allosteric site, where several nitrovinyl compounds can bind to inhibit FBPase activity. Herein, a series of nitrostyrene derivatives were further synthesized, and their inhibitory activities against FBPase were investigated in vitro. Most of the prepared nitrostyrene compounds exhibit potent FBPase inhibition (IC 50  < 10 μM). Specifically, when the substituents of F, Cl, OCH 3 , CF 3 , OH, COOH, or 2-nitrovinyl were installed at the R 2 (meta-) position of the benzene ring, the FBPase inhibitory activities of the resulting compounds increased 4.5-55 folds compared to those compounds with the same groups at the R 1 (para-) position. In addition, the preferred substituents at the R 3 position were Cl or Br, thus compound HS36 exhibited the most potent inhibitory activity (IC 50  = 0.15 μM). The molecular docking and site-directed mutation suggest that C128 and N125 are essential for the binding of HS36 and FBPase, which is consistent with the C128-N125-S123 allosteric inhibition mechanism. The reaction enthalpy calculations show that the order of the reactions of compounds with thiol groups at the R 3 position is Cl > H > CH 3 . CoMSIA analysis is consistent with our proposed binding mode. The effect of compounds HS12 and HS36 on glucose production in primary mouse hepatocytes were further evaluated, showing that the inhibition was 71% and 41% at 100 μM, respectively., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

G-Quadruplex DNAs, formed by G-rich DNA sequences in human genes, are promising targets for design of cancer drugs. In this study, two naphthalimide substituted styryl dyes with different sizes of aromatic groups were synthesized. The spectral analysis showed that the dye X-2 with a large aromatic group formed aggregates in buffer solution displaying very weak fluorescence intensity, and disaggregated in the presence of G-Quadruplex DNAs with large intensity enhancements (up to ~1800 fold). Moreover, X-2 displayed good selectivity to G-Quadruplex DNAs. In contrast, dye X-3 with the smaller aromatic group had much lower fluorescence enhancements and poor selectivity to G-Quadruplex DNAs, suggesting that the suitably sized aromatic ring was essential for the interaction with G-Quadruplex. Further binding studies suggested that X-2 mainly bound on G-quartet surface through end-stacking mode. Cytotoxicity assay showed that both of the two dyes showed good anti-proliferative activities against the cancer cell lines and less cytotoxicity in non-malignant cell lines, which were better than a standard drug 5-fluorouracil. In addition, living cell imaging was also studied and demonstrated the potential applications of the new dye X-2 in bioassays and cell imaging., Competing Interests: Declaration of Competing Interest We declare that we have no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Selective and sensitive detection of G-quadruplex DNA structures is an important issue and attracts extensive interest. To this end, numerous small molecular fluorescent probes have been designed. Here, we present a series of N-alkylated styrylquinolinium dyes named Ls-1, Ls-2 and Ls-3 with varying side groups at the chain end. We found that these dyes exhibited different binding behaviors to DNAs, and Ls-2 with a sulfonato group at the chain end displayed sensitivity and selectivity to G-quadruplex DNA structures in vitro. The characteristics of this dye and its interaction with G-quadruplex DNA were comprehensively investigated by means of UV-vis spectrophotometry, fluorescence, circular dichroism and molecular docking. Furthermore, confocal fluorescence images and MTT assays indicated dye Ls-2 could pass through membrane and enter the living HepG2 cells with low cytotoxicity., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

In vivo monitoring of the biodistribution and activation of prodrugs is highly attractive, and the self-immolative dendritic architecture is deemed as a promising approach for constructing theranostic prodrug in which the release/activation of different payloads is needed. Herein, A GSH-triggered and self-immolative dendritic platform comprising an anticancer drug camptothecin (CPT), a cleavable linker and a two-photon NIR fluorophore (dicyanomethylene-4H-pyran, DCM) has been developed for in situ tracking of drug release and antitumour therapy. In vitro experiments demonstrate that, the presence of glutathione (GSH) induces the cleavage of the self-immolative linker, resulting in comitant release of the drug and the dye. Upon cell internalization and under one- or two-photon excitation, prominent intracellular fluorescence can be observed, indicating the release of the payloads in live cells. Upon loaded in phospholipid vesicles, the prodrug has also been successfully utilized for in vivo and in situ tracking of drug release and cancer therapy in a mouse model. Several hours post injection, the prodrug generates strong fluorescence on tumour sites, demonstrating the prodrug's capability of monitoring the on-site drug release. Moreover, the prodrug shows considerable high activity and exerts obvious inhibition towards tumour growth. This work suggests that the prodrug with self-immolative dendritic structure can work well in vivo and this strategy may provide an alternative approach for designing theranostic drug delivery systems., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Aiming at the limited effectiveness of current clinical therapeutic effect of AIDS, novel series of compounds bearing (E)-3,4-dihydroxystyryl sulfone (or sulfoxide) and anilide fragments were designed and synthesized as dual inhibitors of HIV-1 CCR5/IN. The biological results indicated that several target compounds showed inhibitory activity against HIV-1 Bal (R5) infection in TZM-bl cells. Besides targeting the chemokine receptor on the host cell surface, they also displayed binding affinities with HIV-1 integrase using the surface plasmon resonance (SPR) binding assays. Molecular docking studies have inferred the possible binding mode of target compounds against integrase. These data demonstrate that the structure of (E)-3,4-dihydroxystyryl sulfone and sulfoxide derivatives have the potential to derive potent dual inhibitors of HIV-1 Integrase and CCR5., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Detection of cerebral β-amyloid (Aβ) by targeted contrast agents is of great interest for in vivo diagnosis of Alzheimer's disease (AD). Partly because of their planar structure several bis-styrylbenzenes have been previously reported as potential Aβ imaging agents. However, these compounds are relatively hydrophobic, which likely limits their in vivo potential. Based on their structures, we hypothesized that less hydrophobic bis-pyridylethenylbenzenes may also label amyloid. We synthesized several bis-pyridylethenylbenzenes and tested whether these compounds indeed display improved solubility and lower LogP values, and studied their fluorescent properties and Aβ binding characteristics. Bis-pyridylethenylbenzenes showed a clear affinity for Aβ plaques on both human and murine AD brain sections. Competitive binding experiments suggested a different binding site than Chrysamine G, a well-known stain for amyloid. With a LogP value between 3 and 5, most bis-pyridylethenylbenzenes were able to enter the brain and label murine amyloid in vivo with the bis(4-pyridylethenyl)benzenes showing the most favorable characteristics. In conclusion, the presented results suggest that bis-pyridylethenylbenzene may serve as a novel backbone for amyloid imaging agents., (Copyright © 2016. Published by Elsevier Ltd.)

1,3,8-Trihydroxynaphthalene reductase (3HNR) is an essential enzymes that is involved in fungal melanin biosynthesis. Based on the structural informations of active site of 3HNR, a series of β-nitrostyrene compounds were rationally designed and synthesized. The enzymatic activities of these compounds showed that most of them exhibited high inhibitory activities (<5.0 μM) against 3HNR; compound 3-2 exhibit the highest inhibitory activity (IC50=0.29 μM). In particular, some of these compounds had moderate fungicidal activity against Magnaporthe grisea. Compound 3-4 showed high in vivo activities against M. grisea (EC50=9.5 ppm). Furthermore, compound 3-2 was selected as a representative molecule, and the probable binding mode of this compound and the surrounding residues in the active site of 3HNR was elucidated by using molecular dock. The positive results suggest that β-nitrostyrene derivatives are most likely to be promising leads toward the discovery of novel agent of rice blast., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Natural products serve as a key source for the design, discovery and development of potentially novel drug like candidates for life threatening diseases. Curcumin is one such medicinally important molecule reported for an array of biological activities. However, it has major drawbacks of very poor bioavailability and solubility. Alternatively, structural analogs and degradants of curcumin have been investigated, which have emerged as promising scaffolds with diverse biological activities. Dehydrozingerone (DZG) also known as feruloylmethane, is one such recognized degradant which is a half structural analog of curcumin. It exists as a natural phenolic compound obtained from rhizomes of Zingiber officinale, which has attracted much attention of medicinal chemists. DZG is known to have a broad range of biological activities like antioxidant, anticancer, anti-inflammatory, anti-depressant, anti-malarial, antifungal, anti-platelet and many others. DZG has also been studied in resolving issues pertaining to curcumin since it shares many structural similarities with curcumin. Considering this, in the present review we have put forward an effort to revise and systematically discuss the research involving DZG with its biological diversity. From literature, it is quite clear that DZG and its structural analogs have exhibited significant potential in facilitating design and development of novel medicinally active lead compounds with improved metabolic and pharmacokinetic profiles., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

A sample treatment step based on solid-phase extraction (SPE) with polymeric sorbents has been developed for the simultaneous isolation and preconcentration of nucleosides and nucleobases from urine prior to analyses by CE-ESI-MS. In most reported methods nucleosides are isolated from urine by SPE in affinity mode, using an immobilized phenylboronic acid group, which specifically binds cis-diols. However, this is not applicable to non-cis-diol compounds. Here, different types of polymeric sorbents were evaluated for the simultaneous extraction of nucleosides and nucleobases from urine. The best results were obtained with Isolute ENV+, a hydroxylated styrene-divylbenzene polymer, whose retention capacity can be attributed mainly to hydrophobic interactions, and thus it can be applied to a broad range of compounds, regardless of whether they present or not to the cis-diol group in their structure. Other parameters such as the elution solvent and sample volume were optimized. We also studied the influence of the addition of isotopically labeled internal standards (ILISs) before or after the extraction step. The detection limits achieved were in the 0.04-0.17μg/mL range for a sample size of 2.0mL and relative standard deviations were 4-22%. The whole method developed, SPE prior to CE-ESI-MS, was applied to human urine samples from healthy volunteers. We conclude that SPE with polymeric sorbents prior to the electrophoretic CE-ESI-MS methodology constitutes a fast, valid and reliable approach for the simultaneously extraction of urinary nucleosides and nucleobases., (Copyright © 2013 Elsevier B.V. All rights reserved.)

This paper presents an improved synthesis of trans-chalcones and α,α'-bis(arylmethylidene) cycloalkanones under ultrasound irradiation in the presence of commercial acid-resins as catalysts in solvent free conditions. Several trans-chalcones and α,α'-bis(arylmethylidene) cycloalkanones were synthesized in good yields and excellent selectivity in a short reaction time., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A task-specific ionic liquid (TSIL) has been introduced as a recyclable catalyst in Michael addition. A series of nitroalkenes and various C-based nucleophiles were reacted in the presence of 30mol% of recyclable basic-functionalized ionic liquid. Good to excellent yields were obtained in 30min under ultrasound irradiation., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Our previous studies demonstrated that two cytotoxic β-nitrostyrene derivatives, 3,4-methylenedioxy-β-nitrostyrene (MNS) and 4-O-benzoyl-3-methoxy-β-nitrostyrene (BMNS) exhibit potent anti-platelet activities. In this study, a series of β-nitrostyrenes were synthesized and subjected to anti-platelet aggregation assay and cytotoxicity assay. The mono- and di-substitutions on the B ring of BMNS tended to increase the anti-platelet activity and decrease the cytotoxic activity. Of these, compounds 19 and 24 exhibited the most potent inhibitory effects on thrombin- and collagen-induced platelet aggregation (IC(50)≤0.7 μM) without significant cytotoxicity on a human cancer cell line (up to 20 μM). Further studies indicated that compounds 19 and 24 inhibited platelet aggregation via prevention of glycoprotein IIb/IIIa activation. The potent and novel effects of BMNS derivatives make them attractive candidates for the development of new anti-platelet agents., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Human noroviruses (NoV) are now recognized as the most frequent cause of outbreaks and sporadic cases of acute gastroenteritis. Despite the significant economic impact and considerable morbidity of norovirus disease, no drug or vaccine is currently available to treat or prevent this disease, therefore the discovery of anti-norovirus drugs is urgent. In the present work, a total of 12 structure related chromone and (E)-2-styrylchromones were evaluated for their potential anti-norovirus activity using the murine norovirus (MNV) as a surrogate model for human NoV. From the 12 compounds studied, six (E)-2-styrylchromones were found to have with interesting anti-norovirus activity. The best compounds of the series were (E)-5-hydroxy-2-styrylchromone and (E)-4'-methoxy-2-styrylchromone with an IC(50) approximately 7muM. A first insight into the mechanism of action of these compounds was possible. An interesting relationship between the anti-norovirus activity and the chemical structure was observed. The present study points out that the (E)-2-styrylchromones skeleton is an important one which deserves to be developed and further explored as new antiviral drugs against NoV., (Copyright 2010 Elsevier Ltd. All rights reserved.)

As part of a broad-based SAR investigation of E-resveratrol (strong sirtuin activator and antineoplastic) and the anticancer vascular-targeting combretastatin-type stilbenes, a series of twenty-three beta-E-nitrostyrenes was synthesized in order to evaluate potential antineoplastic, antitubulin, and antimicrobial activities. The beta-E-nitrostyrenes evaluated ranged from monosubstituted phenols to trimethoxy and 3-methoxy-4,5-methylenedioxy derivatives. Two of the beta-nitrostyrenes were synthesized as water-soluble sodium phosphate derivatives (4t, 4v). All except four (4r, 4s, 4t, 4u) of the series significantly inhibited a minipanel of human cancer cell lines. All but eight led to an IC(50) of <10 microM for inhibition of tubulin polymerization, and all except three (4l, 4t, 4v) displayed antimicrobial activity.

2-Styrylchromones (2-SC) are a chemical family of oxygen heterocyclic compounds, vinylogues of flavones (2-phenylchromones), whose occurrence in nature has been reported. Recently, several 2-SC derivatives were demonstrated to have antioxidant properties, namely, xanthine oxidase inhibition, hepatoprotection against pro-oxidant agents in cellular and non-cellular systems and scavenging activity against reactive oxygen and reactive nitrogen species (ROS and RNS). Considering these antioxidant properties, it may be hypothesised that the electrochemical redox behaviour of 2-SC contributes significantly to their activity. To test this hypothesis, the electrochemical behaviour of different 2-SC was studied, together with a number of flavonoids with well-known antioxidant activities, by cyclic voltammetry, and the results correlated to their ability to scavenge ROS and RNS. The results obtained showed that 2-SC with a catecholic B-ring have a low oxidation peak potential corresponding to the oxidation of the 3',4'-OH (catechol) moiety. The compounds with a phenolic B-ring have a common peak, with oxidation potential values of about +0.4/+0.5 V versus Ag/AgCl, corresponding to the oxidation of the 4'-OH. The oxidation of the hydroxyl substituents in the A-ring generated peaks of higher potentials (+0.7/+0.8 V vs Ag/AgCl). The results from the scavenging assays were in agreement with those obtained from the cyclic voltammetry, that is, higher scavenging effects corresponded to lower values of oxidation potentials, with significant correlation coefficients. The values obtained for the studied flavonoids are in accordance with the literature, and reflect their relative antioxidant activity, when compared to the studied 2-SC. Thus, in this family of compounds, oxidation potentials obtained by cyclic voltammetry seem to be applicable as a general indicator of radical scavenging activity.

4'-methoxy-2-styrylchromone, a new synthetic chromone was identified as a selective proliferation inhibitor of human tumor (MCF-7 and NCI-H460) cell lines than to non-tumor cells (MRC-5). The antiproliferative activity of this chromone was also extensive to peripheral human lymphocytes. 4'-Methoxy-2-styrylchromone was found to block tumor cells in the G2/M phase of the cell cycle. The G2/M arrest of NCI-H460 cells was dose- and time-dependent, reaching a maximum after 12-h treatment while MCF-7 cells reached the maximum value of G2/M accumulation only after a 24-h treatment. Chromone-treated cells evidenced a high frequency of cells in prometaphase, indicating progression beyond G2 and arrest early in mitosis. This mitotic arrest was associated with abnormal mitotic spindles characterized by the formation of a monopolar structure, suggesting that the chromone interferes with microtubules. The results of an in vitro tubulin polymerization assay showed that this chromone stabilizes microtubules in a manner similar to paclitaxel.

2-Styrylchromones are a small group of naturally occurring chromones, vinylogues of flavones (2-phenylchromones). Natural and synthetic 2-styrylchromones have been tested in different biological systems, showing activities with potential therapeutic applications. In particular, the potential and hitherto understudied antioxidant behavior of these compounds has been raised as a matter of interest. Thus the present work consisted in the study of the in vitro scavenging activities for reactive oxygen species (ROS) and reactive nitrogen species (RNS) of various 2-styrylchromone derivatives and structurally similar flavonoids. Some of the studied 2-styrylchromones proved to be extremely efficient scavengers of the different ROS and RNS, showing, in some cases, IC(50)s under 1 microM. The hydroxylation pattern of 2-styrylchromones, especially in the B-ring but also in the A ring, modulates the activity of these compounds, the catecholic derivatives being the most effective scavengers. The styryl pattern also contributes to their observed outstanding antioxidant activity. In conclusion, the scavenging activities for ROS/RNS of 2-styrylchromone derivatives, here shown for the first time, provide novel and most promising compounds to be applied as antioxidants.

Esterification of glycyrrhetinic acid (GA) with dehydrozingerone (DZ) resulted in a novel cytotoxic GA-DZ conjugate. Based on this exciting finding, we conjugated eleven different DZ analogs with GA or other triterpenoids, including oleanoic acid (OA) or ursolic acid (UA). In an in vitro anti-cancer assay using nine different human tumor cell lines, most of the GA-DZ conjugates showed significant potency. Particularly, compounds 5, 29, and 30 showed significant cytotoxic effects against LN-Cap, 1A9, and KB cells with ED(50) values of 0.6, 0.8, and 0.9 microM, respectively. Similar conjugates between DZ and OA or UA were inactive suggesting that the GA component is critical for activity. Notably, although GA-DZ conjugates showed potent cytotoxic activity, the individual components (GA and DZ analogs) were inactive. Thus, GA-DZ conjugates are new chemical entities and represent interesting hits for anti-cancer drug discovery and development.

Protein tyrosine kinases have been known to be involved in regulation of platelet aggregation, suggesting a potential target for antiplatelet therapy. Our previous study showed that 3,4-methylenedioxy-beta-nitrostyrene (MNS) prevented platelet aggregation caused by various stimulators, and this action was accompanied by inhibition of tyrosine kinases. In the present study, in order to examine the structural determinants required for the actions of MNS and to develop more potent tyrosine kinase inhibitors and antiplatelet agents, a new series of beta-nitrostyrene derivatives were synthesized and pharmacologically characterized. The beta-nitrostyrene derivatives inhibited thrombin- or collagen-induced human platelet aggregation, ATP secretion, GPIIb/IIIa activation and protein tyrosine phosphorylation. In recombinant enzyme assay, some beta-nitrostyrene derivatives also demonstrated potent inhibition of Src and/or Syk kinase activity. Furthermore, there was a good correlation between the inhibitory potency of these compounds on tyrosine kinases and on platelet activation/aggregation. Among them, a benzoyl ester derivative (compound 10) possess up to 8-fold greater potency than MNS and over two orders of magnitude greater potency than genistein or tyrphostin A47 in inhibiting platelet responses to thrombin. Our data suggest that beta-nitrostyrenes may represent a new class of tyrosine kinase inhibitors with potent antiplatelet activity.

The purpose of the present study was to obtain nano-scale particles of styrene butadiene rubber. As SBR particles are elastic in nature, conventional methods of size reductions such as impacting, grinding are unable to achieve the final size. So, attempts have been made here to make the nano-particles of the SBR using cavitation technique. Both acoustic and hydrodynamic cavitation techniques have been employed and studied. Hydrodynamic cavitation has been proved to be more energy efficient than the acoustic cavitation on the basis of various parameters. The maximum production rate equivalent to 2 kg/h (solid processing) has been achieved in the newly developed hydrodynamic cavitation set-up (made in house). Similar to transient cavitation, stable cavitation has also been shown to contribute for reduction in the size of the material with very low variation in size. This technique has been proved successful for the size-reduction of the elastic material to nano-scale, thus it may also be used for the size-reduction of the other brittle and hard material by adjusting various cavitational parameters.

A multidisciplinary project was developed, combining the synthesis of a series of beta-nitrostyrene derivatives and the determination of their physicochemical parameters (redox potentials, partition coefficients), to the evaluation of the corresponding antibacterial activity. A complete conformational analysis was also performed, in order to get relevant structural information. Subsequently, a structure-property-activity (SPAR) approach was applied, through linear regression analysis, aiming at obtaining a putative correlation between the physicochemical parameters of the compounds investigated and their antibacterial activity (both against standard strains and clinical isolates). The beta-nitrostyrene compounds displayed a lower activity towards all the tested bacteria relative to the beta-methyl-beta-nitrostyrene analogues. This was observed particularly for the 3-hydroxy-4-methoxy-beta-methyl-beta-nitrostyrene (IVb) against the Gram-positive bacteria (Staphylococcus aureus, Enterococcus faecalis and Enterococcus faecium). The SPAR results revealed the existence of a clear correlation between the redox potentials and the antibacterial activity of the series of beta-nitrostyrene derivatives under study.

The objective of this study was to investigate the effect of combining two biomaterials on osteoblast proliferation, differentiation and mineralised matrix formation in vitro. The first biomaterial has a well-defined architecture and is known as PolyHIPE polymer (PHP). The second biomaterial is a biologically inspired self-assembling peptide hydrogel (RAD16-I, also called PuraMatrix) that produces a nanoscale environment similar to native extracellular matrix (ECM). Our work investigates the effect of combining RAD16-I with two types of PHP (HA (Hydroxyapatite)-PHP and H (Hydrophobic)-PHP) and evaluates effects on osteoblast growth and differentiation. Results demonstrated successful incorporation of RAD16-I into both types of PHP. Osteoblasts were observed to form multicellular layers on the combined biomaterial surface and also within the scaffold. Dynamic cell seeding and culturing techniques were compared to static seeding methods and produced a more even distribution of cells throughout the constructs. Cells were found to penetrate the scaffold to a maximum depth of 3 mm after 35 days in culture. There was a significant increase in cell number in H-PHP constructs coated with RAD16-I compared to H-PHP alone. Our results show that RAD16-I enhances osteoblast differentiation and indicates that the incorporation of this peptide provides a more permissive environment for osteoblast growth. We have developed a microcellular polymer containing a nanoscale environment to enhance cell: biomaterial interactions and promote osteoblast growth in vitro.

Styrenated antibody (ST-Ab) and styrenated gelatin (ST-gelatin) were prepared by condensation reaction of antibody or gelatin with 4-vinylbenzoic acid, respectively. The affinity loss of ST-Ab to its antigen was minimal. ST-Ab and ST-gelatin were copolymerized with by visible-light irradiation in the presence of a water-soluble camphorquinone as a photoinitiator to produce a tissue-adhesive, in situ-formed co-gel of ST-gelatin and ST-Ab. The amount of non-reacted ST-Ab released from the co-gel of ST-gelatin and ST-Ab into the medium was minimal. The confocal laser scanning microscopy observation showed that local accumulation of rhodamine-labeled bovine serum albumin (BSA) as a model antigen was noticed in the surface-to-subsurface region of the co-gel of ST-gelatin and anti-BSA ST-Ab, indicating that the gel prevented the permeation of BSA into the gel. In invasion double chamber assay using anti-hepatocyte growth factor (HGF) antibody, the co-gel prevented HGF-dependent invasion of pancreatic cancer cells. The discussion was made for potential application of an in situ-formed tissue-adhesive co-gel of ST-gelatin and ST-Ab, developed in this study, as a cytokine-barrier on a surgically resected tissue where cancer cells might still remain after resection of cancerous tissue.

A novel micro-cellular polymer with a well-defined and uniform micro-architecture has been developed as a three-dimensional support matrix for in vitro tissue engineering applications. This material is manufactured through a high internal phase emulsion (HIPE) polymerization route and may be modified with hydroxyapatite. The generic form of the support is known as PolyHIPE Polymer (PHP). By changing the chemical composition of the emulsion and the processing conditions, the pore size can be altered from sub-micron range to a few hundred microns and the porosity varied from 70% to 97%. Our work has investigated the use of this micro-porous polymer as a biomaterial to support the growth of osteoblasts, the bone forming cells in vitro. Three groups of polymers were used that had pore sizes of 40, 60 and 100 microm. Results demonstrated in vitro cell-polymer compatibility, with osteoblasts forming multicellular layers on the polymer surface and also migrating to a maximum depth of 1.4mm inside the scaffold after 35 days in culture. PHP was also able to support the differentiation of osteoblasts and the production of a bone-like matrix. The effect of modifying the polymer with hydroxyapatite was also studied and showed that there was a significant increase in osteoblast numbers penetrating into the polymer. There were few differences, between the pore sizes studied, on the overall penetration of osteoblasts into the polymer but the rate of movement into 100 microm PHP was significantly higher compared to the other sizes investigated. This study shows that osteoblasts seeded onto PHP demonstrate cellular attachment, proliferation and ingrowth leading to the support of an osteoblastic phenotype. Therefore this highly porous scaffold has a potential for bone tissue engineering.

A series of substituted styryl-acrylonitriles was designed and synthesized. The new compounds, called tyrenes, were tested for the ability to inhibit acute lymphocytic leukemia (ALL) cancer cell growth, as well as on their toxicity to normal bone marrow (NBM) cells. The results showed that 3,4-dihydroxystyryl-acrylonitriles, in particular CR-4, revealed great potency as antitumor agents, and also exhibited low toxicity to normal cells. The effectiveness of these compounds with extended conjugation may be due to their possible functioning as reactive Michael acceptors.

It is well known that many cell types react strongly to micro-topography. It is rapidly becoming clear than cells will also react to nano-topography. Polymer demixing is a rapid and low-cost chemical method of producing nano-topography. This manuscript investigates human fibroblast response to 27nm high nano-islands produced by polymer demixing. Cell spreading, cytoskeleton, focal adhesion and Rac localisation were studied. The results showed that an initial rapid adhesion and cytoskeletal formation on the islands at 4 days of culture gave way to poorly formed contacts and vimentin cytoskeleton at 30 days of culture.

In the present study, we outlined the part of the molecule mediating the prominent pro-apoptotic effect of the Michael adduct of ascorbic acid with p-chloro-nitrostyrene, a new synthetic phosphatase inhibitor. The nitrostyrene (NS) moiety was identified as the structure essential for apoptosis induction. NS and its ascorbic acid adducts displayed LC(50) values of 10-25 microM with no significant reduction of potency in okadaic acid resistant cells overexpressing the MDR1 P-glycoprotein. Induction of apoptosis by NS derivatives and the protein phosphatase 2A inhibitor cantharidic acid was proven by the analysis of caspase-3 activation and subsequent fragmentation of DNA. Further structure activity analysis revealed the necessity of the nitro group at the beta-position of the side chain. The pro-apoptotic potential of adducts of NS with pyrimidine- or pyridine-derivatives varied between NS and a progressive reduction in potency up to a nearly complete loss of cytotoxicity. Substitutions at the benzene core of NS suggested a prominent enhancement of toxicity only by substitutions at the 2- or 3-position. Heterocyclic aromatics can substitute for the benzene ring of NS albeit with a 2-3-fold reduced potency. In conclusion, nitrostyrene was identified as the core structure mediating the pro-apoptotic effect of a new synthetic phosphatase inhibitor. Further studies defined a nitrovinyl side chain attached to an aromatic ring as the pharmacophore structure of a new group of pro-apoptotic agents. These observations present the basis for the development of a new group of anticancer drugs.

The extraction properties of two polymeric solid phase extraction materials, styryldivinyl benzene (SDB) and 'Oasis' have been compared with those of a base deactivated C8 bonded silica gel using a range of acidic and basic test analytes. In the case of the two polymer phases good extraction of all the test compounds from aqueous buffer was obtained over the pH range 2-10. On the C8 material, efficient extraction of the most polar acidic analyte, anisic acid, was only obtained between pH 2 and 6. The use of methanol water mixtures, or methanol water mixtures modified with either trifluoroacetic acid (TFA) or triethylamine (TEA) as eluents was investigated for the recovery of the analytes following extraction. The use of TFA or TEA as ionic modifiers strongly influenced the efficiency of the elution step. The effect of a plasma matrix on extraction efficiency was also investigated, with the result depending upon the analyte. An approach to assessing the performance of the three phases has been developed based on the percentages of methanol in the eluent resulting in the recovery of 50% of the analyte, and in determining the difference between eluents giving recoveries of 10 and 90%.

8-(Sulfostyryl)xanthine derivatives were synthesized as water-soluble A2A-selective adenosine receptor (AR) antagonists. meta- and para-sulfostyryl-DMPX (3,7-dimethyl-1-propargylxanthine) derivatives 11a and 11b exhibited high affinity to rat A2A-AR in submicromolar concentrations, and were 20- to 30-fold selective versus rat A1-AR. Styryl-DMPX derivatives were inactive at human A2B- and A3-AR. 1,3-Dipropyl-8-p-sulfostyrylxanthine (13) or only a 7-methyl derivative (14) showed similar (13) or higher (14) A2A affinity than 11a and 11b but showed no (13) or only a low degree (14) of selectivity versus A1-, A2B-, and A3-AR. The A2A-selective sulfostyryl-DMPX derivatives exhibit high water-solubility and may be useful research tools for in vivo studies.

A few structurally related phenols, dehydrozingerone (DZ), bromopentenone (BP), eugenol (EG) and isoeugenol (IEG), derived from plant products show antioxidant properties by inhibiting lipid peroxidation in membrane models. The phenoxyl radicals produced by the scavenging of free radicals during the inhibition of lipid peroxidation, were also generated by specific one-electron oxidants using pulse radiolysis. The radical lifetimes (second order rate constants for radical-radical reactions), reactivities with hydroxyl and model peroxyl radicals and the one-electron reduction potentials with respect to the standard couples were quantified. These results along with their lipophilicity data were correlated with their antioxidant activity (IC50 values).

A series of derivatives of 2,3-dihydro-2-(aryl)-4(1H)-quinazolinone (DHQZ) with known antitumor activity was re-evaluated in the National Cancer Institute cancer cell line screen. Analysis by the COMPARE algorithm suggested that their cytotoxicity derived from interactions with tubulin. Significant inhibition of tubulin assembly and of the binding of radiolabeled colchicine to tubulin was demonstrated with several of the compounds, particularly NSC 145669, 175635, and 175636. The DHQZ derivatives are structurally analogous to a number of antimitotic agents, flavonols and derivatives of 2-styrylquinazolin-4(3H)-one and of 2-phenyl-4-quinolone. Structure-activity analogies between these agents, the combretastatins, and the colchicinoids were analyzed and summarized.

1. Dehydrozingeronolol (DZPN; 0.1, 0.5, 1.0 mg/kg, i.v.) produced a dose-dependent bradycardia response and a sustained pressor action in urethane-anesthetized normotensive rats. DZPN inhibited the tachycardia effects by (-)isoproterenol, but had no blocking effect on the arterial pressor responses induced by phenylephrine. 2. In in vitro study, DZPN antagonized (-)isoproterenol-induced positive chronotropic effects in guinea-pig isolated right atria and relaxation responses in rat isolated uterus horns. 3. DZPN causes mild direct cardiac depression at high concentrations without intrinsic sympathomimetic activity (ISA). 4. The order of potency of beta-adrenoceptor antagonists in competing for the [3H]dihydroalprenolol binding sites was (-)propranolol >> DZPN > or = atenolol.

Whole cells of the propene utilizing Mycobacterium sp. M156 (NCIMB 40156) oxidised styrene, 2-,3- and 4-fluorostyrene, 3- and 4-chlorostyrene and 3- and 4-methylstyrenes to their respective epoxides. Rates of oxidation were comparable to that of styrene. alpha-Methylstyrene was also epoxidised at a lower rate, while trans-beta-methylstyrene and 1,2-dihydronaphthalene were poor substrates. In those cases that were investigated, epoxidation occurred with a high degree of stereospecificity.

Previous studies have shown that high impact strength can be conferred on denture-base poly(methyl methacrylate) polymers by modification with acrylic-terminated butadiene-styrene block copolymers, and that the acrylic end-group was necessary for effective reinforcement. It is now shown that, by solvent extraction studies, grafting of the copolymer occurs both with acrylic-terminated and non-terminated block copolymers. It is therefore concluded that the mode of grafting is different, and some possible mechanisms are discussed.