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This research aims to modify ultrafne fully vulcanized powdered natural rubber (UFPNR) prepared by emulsion \ud graft-copolymerization with styrene (St) and acrylonitrile (AN) monomers onto deproteinized natural rubber (DPNR). \ud The efects of monomers content and St/AN weight ratio on grafting efciency and thermal stability of the devel�oped DPNR-g-(PS-co-PAN) were investigated. The results showed that grafting efciency was enhanced up to 86% with monomers content 15 phr and weight ratio St:AN 80:20. The obtained DPNR-g-(PS-co-PAN) was radiated by an electron beam at various doses, followed by a spray drying process to produce UFPNR. The obtained modifed UFPNR particles irradiated at dose up to 300 kGy were relatively spherical with a particle size of approximately 4.4 µm. Fur�thermore, the degradation temperature of 5wt% loss (Td5) of UFPNR was found in the range of 349–356 °C. The results revealed that the modifed UFPNR is suitable as a toughening fller for a broader spectrum of polymers.

In this work, we report the synthesis and study of nanocomposites with a biobased epoxy/amine (Epilok 60-600G/Curamine 30-952) matrix reinforced with reduced graphene oxide (rGO) or functionalised with 3-glycidoxypropyltrimethoxysilane (GLYMO-rGO). These graphene related materials (GRMs) were first dispersed into a Curamine hardener using bath ultrasonication, followed by the addition of epoxy resin. Curing kinetics were studied by DSC under non-isothermal and isothermal conditions. The addition of 1.5 wt% of GLYMO-rGO into the epoxy matrix was found to increase the degree of cure by up to 12% and glass transition temperature by 14 °C. Mechanical testing showed that the addition of 0.05 wt% GLYMO-rGO improves Young’s modulus and tensile strength by 60% and 16%, respectively, compared to neat epoxy. Carbon fibre reinforced polymer (CFRP) laminates were prepared via hand lay up, using the nanocomposite system GRM/Epilok/Curamine as matrix, and were cut as CFRP adherents for lap shear joints. GRM/Epilok/Curamine was also used as adhesive to bond CFRP/CFRP and CFRP/aluminium adherents. The addition of 0.1 wt% GLYMO-rGO into the adhesive and CRFP adherents showed improved lap shear strength by 23.6% compared to neat resin, while in the case of CFRP/Aluminium joints the increase was 21.2%.

Colorectal cancer (CRC) is the 3rd most common type of cancer worldwide. Late detection plays role in one-third of annual mortality due to CRC. Therefore, it is essential to find a precise and optimal diagnostic and prognostic biomarker for the identification and treatment of colorectal tumorigenesis. Covalently closed, circular RNAs (circRNAs) are a class of non-coding RNAs, which can have the same function as microRNA (miRNA) sponges, as regulators of splicing and transcription, and as interactors with RNA-binding proteins (RBPs). Therefore, circRNAs have been investigated as specific targets for diagnostic and prognostic detection of CRC. These non-coding RNAs are also linked to metastasis, proliferation, differentiation, migration, angiogenesis, apoptosis, and drug resistance, illustrating the importance of understanding their involvement in the molecular mechanisms of development and progression of CRC. In this review, we present a detailed summary of recent findings relating to the dysregulation of circRNAs and their potential role in CRC.

Graft copolymers, deproteinized natural rubber-graft-polystyrene (DPNR-g-PS) and deproteinized natural rubber-graft-polyacrylonitrile (DPNR-g-PAN), were prepared by the grafting of styrene (St) or acrylonitrile (AN) monomers onto DPNR latex via emulsion copolymerization. Then, ultrafine fully vulcanized powdered natural rubbers (UFPNRs) were produced by electron beam irradiation of the graft copolymers in the presence of di-trimethylolpropane tetra-acrylate (DTMPTA) as a crosslinking agent and, subsequently, a fast spray drying process. The effects of St or AN monomer contents and the radiation doses on the chemical structure, thermal stability, and physical properties of the graft copolymers and UFPNRs were investigated. The results showed that solvent resistance and grafting efficiency of DPNR-g-PS and DPNR-g-PAN were enhanced with increasing monomer content. SEM morphology of the UFPNRs showed separated and much less agglomerated particles with an average size about 6 μm. Therefore, it is possible that the developed UFPNRs grafted copolymers with good solvent resistance and rather high thermal stability can be used easily as toughening modifiers for polymers and their composites.

This aim of this study is to prepare four novel oil-in-water creams from 100% naturally sourced oil ingredients such as jojoba, baobab and coconut oil, and compare the effect of the oils on the physico-chemical properties of the creams and their short- and long-term stability. Four 100 g each oil-in-water active containing creams and their controls (without the active ingredient) were formulated and stored in eight separate glass jars. The short-term stability of the creams was assessed via phase separation resistance, pH, microscopic size analysis, globule size, zeta potential, conductivity and microbial challenge evaluation after 8, 14 and 28 days, under three different storage temperature conditions (4 &deg, C, 25 &deg, C and 40 &deg, C) and at ambient relative humidity. Model creams IA, IB, IIA, and IIB containing 1:1 of jojoba and baobab oil mix, all had good shelf-life or stability at the end of the 28 days after storage at 4 &deg, C, compared to models IIIA, IVA and pairs. The long-term stability of creams stored at 25 &deg, C for 28 days, was subsequently assessed using the Dynamic Vapor Sorption system. Model creams IB, IIB, IA and IIA showed the lowest percentage moisture loss or change in mass during a period of desorption steps. Therefore, the creams containing a mixture of jojoba and baobab oils are capable of retaining moisture easily for an extended period of time when compared to the creams containing jojoba and coconut oil or baobab and coconut oil combinations, thus they were proven to be the best products in terms of stability and quality. The stability ranking of the creams using the novel DVS method was in congruence with the results from the short-term stability experiments. This novel DVS method can, therefore, be generically applied in the cosmetic, food and pharmaceutical industries for the evaluation of the long-term stability of semisolids.

The controlled design of biosensors based on the photo-electrochemical technique with high selectivity, sensitivity, and rapid response for monitoring of mono-bioactive molecules, particularly dopamine (DA) levels in neuronal cells is highly necessary for clinical diagnosis. Hierarchical carbon-, nitrogen-doped (CN) nickel oxide spear thistle (ST) flowers associated in single-heads (S), and symmetric and asymmetric-double heads (D and A, respectively) that are tightly connected through a micrometric dipole-like rod or trunk were fabricated by using a simple synthetic protocol. The CN-ST flower heads were decorated with dense nano-tubular like hedgehog needle skins in vertical alignments. These designated architectures are key features for creating biosensor surface electrodes for photo-electrochemical, ultrasensitive screening of mono-bioactive molecules. The exceptional electrode designs produced numerous catalytically active sites, large surface area, and high electron-transfer mobility. The active coating of carbon–nitrogen nanospheres significantly enhanced the photo-electrocatalytic activity of the prepared biosensor electrodes and prevented leakage of photocatalytic activity under long-term exposure to irradiation. Among all photo-electrochemical assays, the biosensors showed significant sensitivity and selectivity for DA in the presence of interfering molecules such as ascorbic acid (AA), uric acid (UA), adrenaline (A), and noradrenaline (NA). The photo-electrochemical property of the CN-SST-{110} crystal surface electrode showed significant sensing performance for DA in terms of unimpeded diffusion pathways, a wide concentration-detection range, and a low detection limit, even in the presence of potentially interfering molecules compared with other electrode-modified CN-DST-{111} and CN-AST-{101} crystal surfaces. Furthermore, the CN-SST photo-biosensor electrode shows potential in the selective and sensitive determination of DA in real samples, such as human serum and secreted DA from living cells. This finding indicates that the hierarchical ST biosensor may enable analytical discrimination and monitoring of DA and can be employed for clinical diagnosis application.

Aberrant activation of the WNT/CTNNB1 pathway is notorious in colorectal cancer (CRC). Here, we demonstrate that the expression of specific and crucial WNT signaling pathway genes is linked to disease progression in colonic adenomatous (AP) and hyperplastic (HP) polyps in an Iranian patient population. Thus, we highlight potential gene expression profiles as candidate novel biomarkers for the early detection of CRC. From a 12-month study (2016-2017), 44 biopsy samples were collected during colonoscopy from the patients with colorectal polyps and 10 healthy subjects for normalization. Clinical and demographic data were collected in all cases, and mRNA expression of APC, CTNNB1, CDH1, AXIN1, and AXIN2 genes was investigated using real-time polymerase chain reaction (PCR). CTNNB1 and CDH1 expression levels were unaltered in AP and HP subjects, whereas mRNA expression of APC was decreased in AP contrasted with HP subjects, with a significant\ud association between APC downregulation and polyp size. Although AXIN1 showed no changes between AP and HP groups, a significant association between AXIN1 and dysplasia grade was found. Also, significant upregulation of AXIN2 in both AP and HP subjects was detected.\ud In summary, we have shown increased expression of AXIN2 and decreased expression of APC correlating with grade of dysplasia and polyp size. Hence, AXIN2 and APC should be explored as biomarker candidates for early detection of AP and HP polyps in CRC.\ud \ud Keywords : Colorectal polyps, gene expression, WNT/CTNNB1 signaling, colorectal cancer, biomarker

The sensory properties of cosmetic products can influence consumers’ choice. The accurate correlation of sensory properties, such as skin hydration, with the material properties of the formulation could be desirable. In this study, we aimed to demonstrate a new method for the in vitro measurement of the refractive indices (RIs) of turbid creams. The critical wavelength of each cream was obtained through direct measurement using a sun protection factor (SPF) meter, the wavelength value was then applied in the Sellmeier equation to determine the RI. The results obtained from the in vitro skin hydration measurement for each cream correlated with their RI values. This suggests that RI measurements could be a useful predictive tool for the ranking of creams in terms of their skin hydration effects.

The authors describe nanoelectrodes based on the use of hierarchical carbon-nitrogen nanospheres and dual-head nickel oxide echinop flowers (CN@HDN) placed on indium tin oxide (ITO) electrodes. The modified electrodes enable sensitive detection of catecholamine neurotransmitters, specifically of epinephrine (EPI) in human serum samples. The modified electrodes possess many active sites along the {111} crystal plane and large contact surfaces. This enables a rapid EPI diffusion within a highly active transport surface. The geometrical and morphological structures of the NiO decorated with CN-nanospheres render superior electrocatalytic behavior at a relatively low working voltage of 0.12 V (vs. Ag/AgCl) which makes the sensor relatively specific. The use of CN also increases the electron transfer rate and facilitates mass transfer between electrolyte (EPI sample) and catalytically active sites. The electrode is sensitive, selective and works at near-physiological pH values. It has a detection limit as low as 4 nM of EPI.

The low molecular weight thiols present in the deproteinized extract of a prostate cancer cell line (LNCaP-FGC) were analysed after derivatization with the Ellman reagent (ESSE). The mixed disulphides formed (RSSE) were fractionated, characterized and quantified by liquid chromatography on a C-18 column using UV detection. This revealed the presence, in femtomoles per cell, of glutathione (8.30 ± 0.73), cysteine (2.71 ± 0.04) and cysteinylglycine (0.83 ± 0.10), accounting for the bulk of the thiol present. Further analysis of the cell extracts using a novel and sensitive mass spectrometry technique allowed the detection of low level of an additional derivative which was identified as cysteinylglycerate using NMRspectroscopy.

Hyaluronic acid (HA) is a natural polysaccharide with promising applications in modern cosmetic and nutricosmetic products due to its high-water affinity, which is essential for skin hydration, as well as its biocompatibility, biodegradability, non-toxicity, and non-immunogenic nature. In this study, we investigated and optimized the method of crosslinking for formulating novel HA hydrogel films. We used Pentaerythritol Tetra-acrylate (PT) as the cross-linking agent over a range of pH values and used different cross-linking methods (Ultraviolet (UV) radiation, microwaving, and oven heating). The efficacy of the cross-linking reaction was evaluated using swelling studies and Fourier transform infrared (FTIR) spectroscopy for the characterization of the xerogel HA-PT film formulations. We found that HA-PT cross-linked hydrogels are produced under alkaline conditions (pH 11) but not under neutral or acidic conditions. Cross-linked HA-PT xerogel films using UV-irradiation showed excessive swelling indicative of inadequate cross-linking. The oven and microwaving methods produced HA-PT films with high cross-linking density. FTIR data suggest formation of ester bond between the carbonyl of the HA and hydroxyl group of the PT acrylate group. Overall, the oven method was considered better and easier than UV-radiation/microwave methods because it is safer, user-friendly and eco-friendly, and can process larger batches.

Extracellular regulated kinase 5 (ERK5) signalling has been implicated in driving a number of cellular phenotypes including endothelial cell angiogenesis and tumour cell motility. Novel ERK5 inhibitors were identified using high throughput screening, with a series of pyrrole-2-carboxamides substituted at the 4-position with an aroyl group being found to exhibit IC50 values in the micromolar range, but having no selectivity against p38α MAP kinase. Truncation of the N-substituent marginally enhanced potency (∼3-fold) against ERK5, but importantly attenuated inhibition of p38α. Systematic variation of the substituents on the aroyl group led to the selective inhibitor 4-(2-bromo-6-fluorobenzoyl)-N-(pyridin-3-yl)-1H-pyrrole-2-carboxamide (IC50 0.82 μM for ERK5; IC50 > 120 μM for p38α). The crystal structure (PDB 5O7I) of this compound in complex with ERK5 has been solved. This compound was orally bioavailable and inhibited bFGF-driven Matrigel plug angiogenesis and tumour xenograft growth. The selective ERK5 inhibitor described herein provides a lead for further development into a tool compound for more extensive studies seeking to examine the role of ERK5 signalling in cancer and other diseases.

α-Methylacyl-CoA racemase (AMACR; P504S) catalyses an essential step in the degradation of branched-chain fatty acids and the activation of ibuprofen and related drugs. AMACR has gained much attention as a drug target and biomarker, since it is found at elevated levels in prostate cancer and several other cancers. Herein, we report the synthesis of 2-(phenylthio)propanoyl-CoA derivatives which provided potent AMACR inhibitory activity (IC50 = 22–100 nM), as measured by the AMACR colorimetric activity assay. Inhibitor potency positively correlates with calculated logP, although 2-(3-benzyloxyphenylthio)propanoyl-CoA and 2-(4-(2-methylpropoxy)phenylthio)propanoyl-CoA were more potent than predicted by this parameter. Subsequently, carboxylic acid precursors were evaluated against androgen-dependent LnCaP prostate cancer cells and androgen-independent Du145 and PC3 prostate cancer cells using the MTS assay. All tested precursor acids showed inhibitory activity against LnCaP, Du145 and PC3 cells at 500 µM, but lacked activity at 100 µM. This is the first extensive structure-activity relationship study on the influence of side-chain interactions on the potency of novel rationally designed AMACR inhibitors.

A series of imidazo[1,2- b]pyridazin-8-amine kinase inhibitors were discovered to allosterically inhibit the endoribonuclease function of the dual kinase-endoribonuclease inositol-requiring enzyme 1α (IRE1α), a key component of the unfolded protein response in mammalian cells and a potential drug target in multiple human diseases. Inhibitor optimization gave compounds with high kinome selectivity that prevented endoplasmic reticulum stress-induced IRE1α oligomerization and phosphorylation, and inhibited endoribonuclease activity in human cells. X-ray crystallography showed the inhibitors to bind to a previously unreported and unusually disordered conformation of the IRE1α kinase domain that would be incompatible with back-to-back dimerization of the IRE1α protein and activation of the endoribonuclease function. These findings increase the repertoire of known IRE1α protein conformations and can guide the discovery of highly selective ligands for the IRE1α kinase site that allosterically inhibit the endoribonuclease.

New graphene/polymer nanocomposites were prepared using graphene nanoplatelets (GNPs) and the epoxy system Epilok 60–566/Curamine 32–494. The GNPs were first dispersed into the curamine hardener using bath ultrasonication, followed by the addition of the epoxy resin. The cure kinetics were studied by DSC under non-isothermal and under isothermal conditions. The kinetic parameters of the curing process were determined using the non-isothermal Kissinger and Ozawa-Flynn-Wall models. The degree of curing increased with the addition of GNPs, while the activation energy decreased by 13.7 % for the primary amine reaction and by 6.6 % for the secondary amine reaction with epoxy groups as obtained from Kissinger. An increase in thermal stability by the addition of GNPs was identified in the range of 360–580 ℃ using TGA. In terms of mechanical properties, addition of an optimum amount of 0.5 %wt of GNPs in the hardener improved the Young’s Modulus by 37 %. Nanoindentation measurements showed 9.4 % improvement in hardness at 0.7 %wt.

Aims and Objectives: Secondary metabolism in marine organisms produces a diversity of biologically important natural compounds that are not present in terrestrial species. Sea cucumbers belong to the invertebrate Echinodermata and are famous for their nutraceutical, medical and food values. They are known for possession triterpenoid glycosides (saponins) with various ecological roles. The current work aimed to separate, identify and test various biological activities (antibacterial, antifungal, antileishmanial and anticancer properties) of saponins produced by the holothurian Pearsonothuria graeffei from the Red Sea, Egypt. Materials and Methods: The structures were identified by 1D and 2D NMR (1H, 13C, TOCSY, COSY, HSQC, HMBC, and ROESY) experiments and acid hydrolysis. The crude and purified fractions was analyzed using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS)/MS to identify saponins and characterize their molecular structures. Partially purified fraction, mainly containing compounds 1 and 2, was screened for its antifungal activity against three clinical isolates of Candida albicans (Candida 580 (1), Candida 581(2) and Candida MEO47228. Antileishmanial activity against Leishmania major and toxicity on colon cell-line were also evaluated. Results: Two lanostane type sulfated triterpene monoglycosides were isolated from the Holothurian Pearsonothuria graeffei from the Red Sea, Egypt. Holothurin A (1) and echinoside A (2) triterpene saponins were separated by reversed phase semi-preparative HPLC. LC50 values (µg/mL); calculated for the fraction containing saponins 1 and 2 as major constituents; against Candida albicans, Leishmania major and colon cell-line were 10, 20 and 0.50, respectively. Conclusion: Consequently, this study demonstrated the potential use of sea cucumber Pearsonothuria graeffei not only as appreciated functional food or nutraceuticals but also as the source of functional ingredients for pharmaceutical products with antifungal, antileishmanial and anticancer properties.

The evaluation of drug–polymer miscibility in the early phase of drug development is essential to ensure successful amorphous solid dispersion (ASD) manufacturing. This work investigates the comparison of thermodynamic models, conventional experimental screening methods (solvent casting, quench cooling), and a novel atomization screening device based on their ability to predict drug–polymer miscibility, solid state properties (Tg value and width), and adequate polymer selection during the development of spray-dried amorphous solid dispersions (SDASDs). Binary ASDs of four drugs and seven polymers were produced at 20:80, 40:60, 60:40, and 80:20 (w/w). Samples were systematically analyzed using modulated differential scanning calorimetry (mDSC) and X-ray powder diffraction (XRPD). Principal component analysis (PCA) was used to qualitatively assess the predictability of screening methods with regards to SDASD development. Poor correlation was found between theoretical models and experimentally-obtained results. Additionally, the limited ability of usual screening methods to predict the miscibility of SDASDs did not guarantee the appropriate selection of lead excipient for the manufacturing of robust SDASDs. Contrary to standard approaches, our novel screening device allowed the selection of optimal polymer and drug loading and established insight into the final properties and performance of SDASDs at an early stage, therefore enabling the optimization of the scaled-up late-stage development.

Monitoring and determination of ultra-trace concentrations of monoamine neurotransmitter such as noradrenaline (NA) in living cells with simple, sensitive and selective assays are significantly interesting. We design NA-electrode sensing system based on C-, N-doped NiO broccoli-like hierarchy (CNNB). The spherical broccoli-head umbrella architectures associated with nano-tubular arrangements enabled to tailor NA biosensor design. The homogenous doping and anisotropic dispersion of CN nanospheres along the entire NB head nanotubes lead to creating of abundant electroactive sites in the interior tubular vessels and outer surfaces for ultrasensitive detection of NA in living cells such as PC12. The CNNB biosensor electrodes showed efficient electrocatalytic activity, enhanced kinetics for electrooxidation of NA, and fast electron-transfer between electrode-electrolyte interface surfaces, enabling synergistic enhancement in sensitivity, and selectivity at a low-detectable concentration of ∼ 6nM and reproducibility of broccoli-shaped NA-electrodes. The integrated CNNB biosensor electrodes showed evidence of monitoring and screening of NA released from PC12 cells under K+ ion-extracellular stimulation process. The unique features of CNNB in terms of NA-selectivity among multi-competitive components, long-term stability during the detection of NA may open their practical, in-vitro application for extracellular monoamine neurotransmitters detection in living cells.

This study was initiated to investigate the effect of PLGA concentration, PVA concentration, internal to external phase ratio (IEPR), PEG molecular weight and concentration on mean particle size, zeta potential, polydispersity index (PDI), percentage drug entrapment and in vitro release profile. Using PLGA (50:50) as the carrier, insulin nanoparticles (NP) were prepared using double emulsion solvent evaporation technique. The particle size was analysed by dynamic light scattering (DLS) and the geometrical shape was examined using scanning electron microscopy (SEM). Mean particle size was highly dependent on the combined effect of PLGA and PVA concentrations. Drug entrapment would be greatly controlled by PLGA concentration and internal to external phase ratio. Addition of PEG could modulate in vitro release behavior of insulin with initial burst at the first 12 h and sustain the drug release for 6 days. Insulin integrity was assessed in vitro using MALDI-TOF mass spectroscopy. The optimised NP formulation, had particle size of 202.60 nm and percent entrapment efficiency (EE) equal to 67.72%, was tested in vivo to examine its hypoglycemic effect after subcutaneous injection. Insulin NP had a significant hypoglycemic effect comparing to free insulin (p

Association rule mining can be combined with complex network theory to automatically create a knowledge base that reveals how certain drugs cause side-effects on patients when they interact with other drugs taken by the patient when they have two or more diseases. The drugs will interact with on-target and off-target proteins often in an unpredictable way. A computational approach is necessary to be able to unravel the complex relationships between disease comorbidities. We built statistical models from the publicly available FAERS dataset to reveal interesting and potentially harmful drug combinations based on sideeffects\ud and relationships between co-morbid diseases. This information is very useful to medical practitioners to tailor patient prescriptions for optimal therapy.

Anatomical Therapeutic Codes (ATC) are a drug classification system which is extensively used in the field of drug development research. There are many drugs and medical compounds that as yet do not have ATC codes, it would be useful to have codes automatically assigned to them by computational methods. Our initial work involved building feedforward multi-layer perceptron models (MLP) but the classification accuracy was poor. To gain insights into the\ud problem we used the Kohonen self-organizing neural network to visualize the relationship between the class labels and the independent variables. The information gained from the learned internal clusters gave a deeper insight into the mapping process. The ability to accurately predict ATC codes was unbalanced due to over and under representation of some ATC classes. Further difficulties arise because many drugs have several, quite different ATC codes because they have\ud many therapeutic uses. We used chemical fingerprint data representing a drugs chemical structure and chemical activity variables. Evaluation metrics were computed,\ud analysing the predictive performance of various self-organizing models.

alpha-Methylacyl-CoA racemase (AMACR; P504S) regulates branchedchain\ud fatty acid degradation, activates Ibuprofen and is a recognised\ud cancer drug target. A novel, facile colorimetric assay was developed\ud based on elimination of 2,4-dinitrophenolate. The assay was used to\ud test 5 known inhibitors, determining IC50 and Ki values, reversibility\ud and characterizing irreversible inhibition.

As the popularity of a cosmetic product on the market extensively depends on consumers&rsquo, perception, it is important for the sensory evaluation to be accurate during the product developmental stage. The focus of this study was to develop a generic method for the quantitative assessment of the sensory attributes of cosmetic creams. Four 100 g oil-in-water (O/W) model creams, containing loaded niosomes and their baselines (without niosomes), were formulated. Quantitative sensory evaluation of the formulated oil-in-water products were performed in three different stages: (a) appearance&mdash, pourability (b) pick-up&mdash, firmness and elasticity/stretchability (c) rub-out&mdash, spreadability and stickiness, using rheological measurements. All measurements were carried out at skin temperature, 32 &plusmn, 1 &deg, C, and a relative humidity (RH) of 33%. The quantitative analysis showed all cream models exhibited shear-thinning, non-Newtonian behavior. Rheological parameters from the yield stress, amplitude sweep and frequency sweep tests were found to provide realistic correlations for the sensory characteristics of pourability and spreadability, firmness, elasticity/stretchability and stickiness, respectively. This novel quantitative assessment method of the sensory characteristics of a cream proved to be highly effective and can be universally applied.

α-Methylacyl-CoA racemase (AMACR; P504S; EC 5.1.99.4) catalyses epimerization of 2-methylacyl-CoAs and is important for the degradation of branched-chain fatty acids and the pharmacological activation of ibuprofen and related drugs. It is also a novel drug target for prostate and other cancers. However, development of AMACR as a drug target has been hampered by the difficulties in assaying enzyme activity. Consequently, reported inhibitors have been rationally designed acyl-CoA esters, which are delivered as their carboxylate prodrugs. The novel colorimetric assay for AMACR based on the elimination of 2,4-dinitrophenolate was developed for high-throughput screening and 20,387 ‘drug-like compounds’ were screened, with a throughput of 768 compounds assayed per day. Pyrazoloquinolines and pyrazolopyrimidines were identified as novel scaffolds and investigated as AMACR inhibitors. The most potent inhibitors have IC 50 values of ~2 µM. The pyrazoloquinoline inhibitor 10a displayed uncompetitive inhibition, whilst 10j displayed mixed competitive inhibition. The pyrazolopyrimidine inhibitor 11k displayed uncompetitive inhibition. This is the first report of the identification of specific drug-like small-molecule AMACR inhibitors by high-throughput screening. Pyrazoloquinolines and pyrazolopyrimidines may also be useful as inhibitors of other CoA-utilizing enzymes.

A new, highly efficient, all-solid-phase synthesis of argifin, a natural product cyclic pentapeptide\ud chitinase inhibitor, is reported. The synthesis features attachment of an orthogonally protected Asp\ud residue to the solid support and assembly of the linear peptide chain by Fmoc SPPS prior to cyclisation\ud and side-chain manipulation on-resin. Introduction of the key N-methyl carbamoyl-substituted Arg\ud side chain is achieved via derivatisation of a selectively protected Orn residue, prior to cleavage from the\ud resin and side-chain deprotection. A severe aspartimide side-reaction observed upon final deprotection\ud is circumvented by the use of a novel aqueous acidolysis procedure. The flexibility of the synthesis is\ud demonstrated by the preparation of a series of argifin analogues designed from the X-ray structure of\ud the natural product in complex with a representative family 18 chitinase.

Chitinase inhibitors have chemotherapeutic potential\ud as fungicides, pesticides, and antiasthmatics. Argifin,\ud a natural product cyclopentapeptide, competitively\ud inhibits family 18 chitinases in the nanomolar to micromolar\ud range and shows extensive substrate mimicry.\ud In an attempt to map the active fragments of this\ud large natural product, the cyclopentapeptide was\ud progressively dissected down to four linear peptides\ud and dimethylguanylurea, synthesized using a combination\ud of solution and solid phase peptide synthesis.\ud The peptide fragments inhibit chitinase B1 from\ud Aspergillus fumigatus (AfChiB1), the human chitotriosidase,\ud and chitinase activity in lung homogenates\ud fromamurinemodel of chronic asthma, withpotencies\ud rangingfromhighnanomolar tohighmicromolar inhibition.\ud X-ray crystallographic analysis of the chitinaseinhibitor\ud complexes revealed that the conformations of the linear peptides were remarkably similar to that of the natural product. Strikingly, the dimethylguanylurea fragment, representing only a quarter of the natural product mass, was found to harbor all significant interactions with the protein and binds with unusually high efficiency. The data provide useful information that could lead to the generation of drug-like, natural product-based chitinase inhibitors.

Aims: Melissa officinalis (Mo) and Lavandula angustifolia (La) essential oils and their major constituents ((E) - caryophyllene, caryophyllene oxide, geranyl acetate, linalool, nerol, Oct-1-en-3-ol, 3-Octanone, myrcene, allo-ocimene, p-cymene and α- terpineol) assessed by GC-MS) which are shared by these two essential oils were probed in an attempt to identify the GABAAR ligand(s).\ud Study Design: [35S] t-butylbicyclophosphorothionate (TBPS) radioligand binding assay to GABAA receptors. In vitro neuronal viability assay.\ud Place and Duration of Study: School of Biological and Biomedical Sciences, Durham University, United Kingdom (December 2012 and January 2013).\ud Results: One of the major component (s) of (Mo), trans-ocimene, inhibited [35S] (TBPS) binding to native GABAA receptors in a concentration-dependent manner with an apparent IC50 of 40μM.\ud Concentrations (0.001 mg/ml) of whole (Mo) were shown to display modest beneficial effects upon neuronal viability while at a higher concentration (0.1 mg/ml) of (Mo) and (La) oils induced a neurotoxicity effect.\ud Conclusion: These data provide the first evidence that allo-ocimene is an neuroactive GABAA R inhibitory component found in both (Mo) and (La), and represents a novel GABAA receptor channel chemotype derived from a natural product. - See more at: http://www.sciencedomain.org/abstract.php?iid=474&id=13&aid=4142#.VCFGHBbQpv0

Maintaining protein conformational stability and integrity during formulation is critical for developing protein pharmaceuticals. Accordingly, high sensitivity differential scanning calorimetry (HSDSC) and Fourier transform (FT)-Raman spectroscopy were employed to assess conformational stabilities (thermal stability and folding reversibility) and structural integrities, respectively, for three model proteins: lysozyme, deoxyribonuclease I (DNase I) and lactate dehydrogenase (LDH) in lyophilised (as received) and spray-dried forms. Enzymatic assay after cooling of thermally denatured protein solutions from HSDSC determined if thermal transition reversibility was related to biological activity. HSDSC data showed that molecules from lyophilised lysozyme were able to refold better than the spray-dried form. This was confirmed by enzymatic assay. Moreover, enzymatic assay results revealed that lysozyme folding reversibility was related to the native structure of the protein that is essential for the biological activity. Thermal denaturation of DNase I and LDH samples in HSDSC was not reversible upon cooling of thermally denatured proteins (in contrast to lysozyme). Hence, it was decided to identify the effect of protein initial structures on its propensity to thermal denaturation via FT-Raman spectroscopy. In other words, proteins may denature with structural alterations due to stresses such as heat and the protein loses its enzymatic activity. Consequently, FT-Raman investigated the effects of spray drying and heating of solid DNase I and LDH samples, from differential scanning calorimetry, on protein conformational integrities. Lyophilised and spray-dried DNase I and LDH solid samples were heated to two temperatures, one before the apparent denaturation temperatures (Tm) and the other after the Tm. Samples heated below their Tm showed some alterations of the secondary structure and some enzymatic activity. HSDSC and FT-Raman spectroscopy are useful techniques to study protein conformations and their results correlate with those of enzymatic activity.

PREDICTIVE MODELING OF LONG-TERM STABILITY OF DRUG-IN-ADHESIVE TRANSDERMAL DRUG DELIVERY SYSTEMS\ud \ud K DODOU\ud University of Sunderland, Sunderland SR1 3SD, UK\ud \ud Transdermal patches are medicated dosage forms that are applied on the skin for the delivery of the active ingredient to the systemic circulation. The attachment of the patch on the skin is due to the adhesive ability of the pressure-sensitive adhesive (PSA) polymer1.\ud With my research group we focused on the drug-in-adhesive patch design, where the active ingredient is incorporated in the PSA, and we have explored the following challenges:\ud \ud • Effect of drug incorporation on the adhesive performance of the PSA. My research findings increased knowledge and understanding on how rheological parameters translate to adhesive performance criteria for different types of pressure sensitive adhesives, and provided new insights and practices on the incorporation of drugs in the adhesive films. Via this work, we established how the rheological properties of adhesives can be used as a quality control indicator for the adhesive performance of transdermal patches2,3. \ud \ud • Long-term stabilisation of drug against crystallisation in the PSA via polymeric amorphous solid dispersions. Drug crystallisation in dosage forms is a formulation defect because it hinders drug release. My research identified formulation and manufacturing approaches to prevent drug crystallisation in transdermal films via amorphous solid dispersions4. Drug stabilisation in lipophilic PSAs (such as silicones and polyisobutylenes) requires the addition of a stabiliser polymer that would form H-bonding interactions with the drug. Whereas drug stabilisation in polar PSAs (ie acrylic) could be feasible via H-bonding interaction with the PSA. We therefore developed predictive models for the estimation of the required polymer amount to stabilise a given drug concentration in lipophilic PSAs5 and for the long-term stability assessment of the drug in polar PSAs6.\ud \ud I would like to acknowledge the financial support from IChemE, Schwarz Pharma and UCB Pharma. \ud \ud 1. K Dodou (2011) The use of adhesive films in transdermal and mucoadhesive dosage forms. In: Adhesive Properties in Nanomaterials, Composites and Films. Nova Science Publishers, New York, pp. 83-93.\ud 2. KY Ho, K Dodou, Rheological studies on pressure sensitive silicone adhesives and drug-in-adhesive layers as a means to characterise adhesive performance, Int.J.Pharm. 333(1-2), 24-33 (2007)\ud 3. HM Wolff, Irsan, K Dodou, Investigations on the viscoelastic performance of pressure sensitive adhesives in drug-in-adhesive type transdermal films, Pharm.Res. 31(8), 2186-2202 (2014)\ud 4. K Dodou, W Saddique, Effect of manufacturing method on the in-vitro drug release and adhesive performance of drug-in-adhesive films containing binary mixtures of ibuprofen with poloxamer 188. Pharm.Dev.Tech. 17(5), 552-561 (2012)\ud 5. C Chenevas-Paule, HM Wolff, M Ashton, M Schubert, K Dodou, Development of a predictive model for the stabilizer concentration estimation in microreservoir transdermal drug delivery systems (MTDDS) using lipophilic pressure sensitive adhesives as matrix/carrier. J.Pharm.Sci. 106(5), 1371-1383 (2017)\ud 6. C Chenevas-Paule, HM Wolff, M Ashton, M Schubert, K Dodou, Development of a predictive model for the long term stability assessment of drug-in-adhesive transdermal films using polar pressure sensitive adhesives as carrier/matrix. J.Pharm.Sci. 106(5), 1293-1301 (2017)