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1.
RSC Adv ; 14(26): 18444-18452, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38860243

RESUMEN

The family of radical-cation salts ß''-(BEDT-TTF)4[(A)M3+(C2O4)3]·guest (M = Fe, Cr, Ga, Al, Co, Mn, Rh, Ru; A = K+, H3O+, NH4 +) has produced superconductors, metals, semiconductors, and metal-insulators through introduction of different guest molecules into the structure. We present three new additions to the family ß''-(BEDT-TTF)4[(A)Cr(C2O4)3]·guest with the guest molecules toluene, phenol, or salicylaldehyde. These new guests are liquid or solid additives within the electrocrystallisation medium. All three salts show metallic behaviour from room temperature down to <10 K and do not show a superconducting transition.

2.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 1): 50-53, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36628361

RESUMEN

In the crystal structure of the title compound, C22H26BN, the B atom acts to reduce the delocalization of the nitro-gen lone-pair electron density into the pyrrole ring, so that the two N-C bonds increase in length to 1.4005 (14) and 1.3981 (14) Å. The N-B bond length is 1.4425 (15) Å, which is longer than a typical N-B bond because the nitro-gen lone pair is not fully available to participate in the bond.

3.
Cureus ; 14(9): e29078, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36259023

RESUMEN

There is literature describing unilateral or focal pulmonary edema due to mitral regurgitation. The proposed mechanism is a regurgitant jet propelling blood towards the orifice of a particular pulmonary vein within the left atrium, which selectively pressurizes that vein. The increased hydrostatic pressure is transmitted to the pulmonary capillaries that drain into that vein, causing focal consolidation. A 62-year-old female presented with acute hypoxic respiratory failure. Her dyspnea started suddenly and she was unresponsive when she arrived at the emergency department via emergency medical services. Her initial oxygen saturation was 23% and she was immediately intubated. Sequential chest radiographs demonstrated dense consolidation in the right upper lung field and then opacification of the right hemithorax. These asymmetric lung findings were suspicious for infectious etiology but she was afebrile with no respiratory secretions and had normal inflammatory markers. Echocardiography showed a ruptured anterior papillary muscle causing a flail mitral valve leaflet with severe mitral regurgitation. The patient developed cardiogenic shock; she had an intra-aortic balloon pump placed for afterload reduction and was taken to the operating room for an emergency mitral valve replacement. Her clinical status rapidly improved and she made a full recovery. As in this case, acute mitral regurgitation can present with sudden life-threatening respiratory failure and cardiogenic shock so prompt diagnosis is critical. This is often misdiagnosed as pneumonia or other respiratory illnesses. Awareness, early diagnosis, and treatment of this entity could provide significant morbidity and mortality benefits for patients.

4.
Dalton Trans ; 51(12): 4843-4852, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35257131

RESUMEN

We report the first examples of radical-cation salts of BEDT-TTF with spiroborate anions [B(mandelate)2]- and [B(2-chloromandelate)2]-, synthesized from either enantiopure or racemic bidentate mandelate or chloromandelate ligands. In the salts prepared using enantiopure ligands only one of two diastereoisomers of the spiroborate anion is incorporated, with the boron centre having the same stereochemistry as the enantiopure ligand. For the racemic salts one racemic pair of spiroborate anions containing an R and an S mandelate ligand is incorporated. In certain solvents helical crystals were obtained when using spiroborate anions with enantiopure ligands. Electrical and magnetic properties, and band structure calculations are reported.

5.
Angew Chem Int Ed Engl ; 60(44): 23878-23884, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34464506

RESUMEN

A combination of charge density studies and solid state nuclear magnetic resonance (NMR) 1 JNC coupling measurements supported by periodic density functional theory (DFT) calculations is used to characterise the transition from an n-π* interaction to bond formation between a nucleophilic nitrogen atom and an electrophilic sp2 carbon atom in a series of crystalline peri-substituted naphthalenes. As the N⋅⋅⋅C distance reduces there is a sharp decrease in the Laplacian derived from increasing charge density between the two groups at ca. N⋅⋅⋅C = 1.8 Å, with the periodic DFT calculations predicting, and heteronuclear spin-echo NMR measurements confirming, the 1 JNC couplings of ≈3-6 Hz for long C-N bonds (1.60-1.65 Å), and 1 JNC couplings of <1 Hz for N⋅⋅⋅C >2.1 Å.

6.
Int J Mol Sci ; 22(11)2021 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-34072234

RESUMEN

A silica-bound C-butylpyrogallol[4]arene chromatographic stationary phase was prepared and characterised by thermogravimetric analysis, scanning electron microscopy, NMR and mass spectrometry. The chromatographic performance was investigated by using C60 and C70 fullerenes in reverse phase mode via flash column and high-pressure liquid chromatography (HPLC). The resulting new stationary phase was observed to demonstrate size-selective molecular recognition as postulated from our in-silico studies. The silica-bound C-butylpyrogallol[4]arene flash and HPLC stationary phases were able to separate a C60- and C70-fullerene mixture more effectively than an RP-C18 stationary phase. The presence of toluene in the mobile phase plays a significant role in achieving symmetrical peaks in flash column chromatography.


Asunto(s)
Cromatografía en Gel/métodos , Cromatografía Líquida de Alta Presión/métodos , Fulerenos/química , Fulerenos/aislamiento & purificación , Técnicas de Química Sintética , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Teoría Cuántica , Dióxido de Silicio/química , Termogravimetría
7.
Chem Commun (Camb) ; 56(66): 9497-9500, 2020 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-32685955

RESUMEN

Materials exhibiting both chirality and conductivity do not exist in nature and very few examples have been synthesised. We report here the synthesis of a chiral molecular metal which remains metallic down to at least 4.2 K. This material also exhibits room-temperature switching capabilities with a transition upon cooling below 10 °C.

8.
Biology (Basel) ; 9(2)2020 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-32098331

RESUMEN

Metastasis is associated with poor prognosis in breast cancer. Although some studies suggest beta-blockers increase survival by delaying metastasis, others have been discordant. This study provides both insights into the anomalous findings and identifies potential biomarkers that may be treatment targets. Cell line models of basal-type and oestrogen receptor-positive breast cancer were profiled for basal levels of adrenoceptor gene/protein expression, and ß2-adrenoceptor mediated cell behaviour including migration, invasion, adhesion, and survival in response to adrenoceptor agonist/antagonist treatment. Protein profiling and histology identified biomarkers and drug targets. Baseline levels of adrenoceptor gene expression are higher in basal-type rather than oestrogen receptor-positive cancer cells. Norepinephrine (NE) treatment increased invasive capacity in all cell lines but did not increase proliferation/survival. Protein profiling revealed the upregulation of the pro-metastatic gene Ly6/PLAUR Domain-Containing Protein 3 (LYPD3) in norepinephrine-treated MDA-MB-468 cells. Histology confirmed selective LYPD3 expression in primary and metastatic breast tumour samples. These findings demonstrate that basal-type cancer cells show a more aggressive adrenoceptor-ß2-activated phenotype in the resting and stimulated state, which is attenuated by adrenoceptor-ß2 inhibition. This study also highlights the first association between ADRß2 signalling and LYPD3; its knockdown significantly reduced the basal and norepinephrine-induced activity of MCF-7 cells in vitro. The regulation of ADRß2 signalling by LYPD3 and its metastasis promoting activities, reveal LYPD3 as a promising therapeutic target in the treatment of breast and other cancers.

9.
Phys Chem Chem Phys ; 22(6): 3400-3413, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31984388

RESUMEN

A combined multinuclear solid state NMR and gauge included projected augmented wave, density functional theory (GIPAW DFT) computational approach is evaluated to determine the four heteronuclear 1J(13C,17O) couplings in solid 17O enriched naphthalaldehydic acid. Direct multi-field 17O magic angle spinning (MAS), triple quantum MAS (3QMAS) and double rotation (DOR) experiments are initially utilised to evaluate the accuracy of the DFT approximations used in the calculation of the isotropic chemical shifts (δiso), quadrupole coupling constants (CQ) and asymmetry (ηQ) parameters. These combined approaches give δiso values of 313, 200 and 66 ppm for the carbonyl (C[double bond, length as m-dash]O), ether (-O-) and hydroxyl (-OH) environments, respectively, with the corresponding measured quadrupole products (PQ) being 8.2, 9.0 and 10.6 MHz. The geometry optimised DFT structure derived using the CASTEP code gives firm agreement with the shifts observed for the ether (δiso = 223, PQ = 9.4 MHz) and hydroxyl (δiso = 62, PQ = 10.5 MHz) environments but the unoptimised experimental XRD structure has better agreement for the carbonyl group (δiso = 320, PQ = 8.3 MHz). The determined δiso and ηQ values are shown to be consistent with bond lengths closer to 1.222 Å (experimental length) rather than the geometry optimised length of 1.238 Å. The geometry optimised DFT 1J(13C,17O) coupling to the hydroxyl is calculated as 20 Hz and the couplings to the ether were calculated to be 37 (O-C[double bond, length as m-dash]O) and 32 (O-C-OH) Hz. The scalar coupling parameters for the unoptimised experimental carbonyl group predict a 1J(13C,17O) value of 28 Hz, whilst optimisation gives a value of 27 Hz. These calculated 1J(13C,17O) couplings, together with estimations of the probability of each O environment being isotopically labelled (determined by electrospray ionisation mass spectrometry) and the measured refocussable transverse dephasing (T2') behaviour, are combined to simulate the experimental decay behaviour. Good agreement between the measured and calculated decay behaviour is observed.

10.
Chem Commun (Camb) ; 56(12): 1792-1794, 2020 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-31942912

RESUMEN

A novel co-pillar[4+1]arene incorporating two bromo-octyl substituents has been synthesised for the first time, using microwave irradiation in high yield (88%) in under four minutes, and bound to the surface of chromatographic silica particles. The resulting new stationary phase has been successfully utilised to separate xylene isomers via liquid chromatographic techniques.

11.
J Med Chem ; 61(17): 7942-7951, 2018 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-30059212

RESUMEN

Autotaxin is an extracellular phospholipase D that catalyzes the hydrolysis of lysophosphatidyl choline (LPC) to generate the bioactive lipid lysophosphatidic acid (LPA). Autotaxin has been implicated in many pathological processes relevant to cancer. Intraperitoneal administration of an autotaxin inhibitor may benefit patients with ovarian cancer; however, low molecular mass compounds are known to be rapidly cleared from the peritoneal cavity. Icodextrin is a polymer that is already in clinical use because it is slowly eliminated from the peritoneal cavity. Herein we report conjugation of the autotaxin inhibitor HA155 to icodextrin. The conjugate inhibits autotaxin activity (IC50 = 0.86 ± 0.13 µg mL-1) and reduces cell migration. Conjugation of the inhibitor increased its solubility, decreased its membrane permeability, and improved its intraperitoneal retention in mice. These observations demonstrate the first application of icodextrin as a covalently-bonded drug delivery platform with potential use in the treatment of ovarian cancer.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Icodextrina/química , Neoplasias Ováricas/tratamiento farmacológico , Hidrolasas Diéster Fosfóricas/química , Animales , Antineoplásicos/síntesis química , Femenino , Humanos , Ratones , Ratones Desnudos , Estructura Molecular , Neoplasias Ováricas/enzimología , Neoplasias Ováricas/patología , Hidrolasas Diéster Fosfóricas/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Dalton Trans ; 46(13): 4225-4234, 2017 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-28280818

RESUMEN

The chiral TTF-based donor molecule bis(2'-hydroxylpropylthio)(ethylenedithio)tetrathiafulvalene (BHPT-EDT-TTF) has produced enantiopure R,R and S,S radical-cation salts with polyiodide anions I3- and I82-. Enantiomorphic 6 : 6 donor : I3 phases grown from either the R,R or S,S donor are semiconducting with similar activation energies of 0.24-0.30 eV and 0.22-0.23 eV, respectively, and contain three unique face-to-face donor pairs whose relative orientation is determined by side chain conformations and hydrogen bonding. Racemic material under the same conditions gave an insulating centrosymmetric phase with R,R and S,S donor cations in a face-to-face pair partnered with an octaiodide dianion, and with a ca. 3 : 1 disorder between the enantiomers. Enantiopure BHPT-EDT-TTF yielded two further insulating crystalline phases of composition 2 : 2 with triiodide and 2 : 1 with octaiodide.

14.
Mo Med ; 114(3): 150, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-30228566
15.
Inorg Chem ; 55(17): 8543-51, 2016 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-27517741

RESUMEN

Molecules of tris(2,2'-bipyridine-4-thiomethyl-BEDT-TTF)iron(II) (BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene) assemble in pairs to form a novel supramolecular capsular structure in the solid state. Three BEDT-TTF residues from one complex lie in the three grooves between coordinated bipyridines of the other complex, and vice versa, to form a capsule with 3-fold rotational symmetry and an internal volume of ca. 160 Å(3). Further aspects of the coordination chemistry of this ligand, its 6-substituted isomer, and the 2,2':6'2″-terpyridyl-4'-thiomethyl-BEDT-TTF analogue are described.

16.
Nat Genet ; 48(8): 827-37, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27294619

RESUMEN

Local concentrations of mutations are well known in human cancers. However, their three-dimensional spatial relationships in the encoded protein have yet to be systematically explored. We developed a computational tool, HotSpot3D, to identify such spatial hotspots (clusters) and to interpret the potential function of variants within them. We applied HotSpot3D to >4,400 TCGA tumors across 19 cancer types, discovering >6,000 intra- and intermolecular clusters, some of which showed tumor and/or tissue specificity. In addition, we identified 369 rare mutations in genes including TP53, PTEN, VHL, EGFR, and FBXW7 and 99 medium-recurrence mutations in genes such as RUNX1, MTOR, CA3, PI3, and PTPN11, all mapping within clusters having potential functional implications. As a proof of concept, we validated our predictions in EGFR using high-throughput phosphorylation data and cell-line-based experimental evaluation. Finally, mutation-drug cluster and network analysis predicted over 800 promising candidates for druggable mutations, raising new possibilities for designing personalized treatments for patients carrying specific mutations.


Asunto(s)
Biología Computacional/métodos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Mutación/genética , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Neoplasias/genética , Neoplasias/metabolismo , Algoritmos , Antineoplásicos/farmacología , Bases de Datos Farmacéuticas , Bases de Datos de Proteínas , Humanos , Modelos Moleculares , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamiento farmacológico , Unión Proteica , Mapas de Interacción de Proteínas , Estructura Terciaria de Proteína
17.
Dalton Trans ; 45(22): 9285-93, 2016 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-27181137

RESUMEN

We have synthesized the first examples of radical-cation salts of BEDT-TTF with chiral borate anions, [B(malate)2](-), prepared from either enantiopure or racemic bidentate malate ligands. In the former case only one of two diastereoisomers of the borate anion is incorporated, while for the hydrated racemic salt one racemic pair of borate anions containing a R and a S malate ligand is incorporated. Their conducting and magnetic properties are reported. The tight-binding band calculation indicates that the chiral salt has an effective half-filled flat band, which is likely to be caused by the chiral structural feature.

18.
Beilstein J Org Chem ; 11: 1561-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26664576

RESUMEN

Chiral molecular crystals built up by chiral molecules without inversion centers have attracted much interest owing to their versatile functionalities related to optical, magnetic, and electrical properties. However, there is a difficulty in chiral crystal growth due to the lack of symmetry. Therefore, we made the molecular design to introduce intermolecular hydrogen bonds in chiral crystals. Racemic and enantiopure bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) derivatives possessing hydroxymethyl groups as the source of hydrogen bonds were designed. The novel racemic trans-vic-(hydroxymethyl)(methyl)-BEDT-TTF 1, and racemic and enantiopure trans-vic-bis(hydroxymethyl)-BEDT-TTF 2 were synthesized. Moreover, the preparations, crystal structure analyses, and electrical resistivity measurements of the novel achiral charge transfer salt θ(21)-[(S,S)-2]3[(R,R)-2]3(ClO4)2 and the chiral salt α'-[(R,R)-2]ClO4(H2O) were carried out. In the former θ(21)-[(S,S)-2]3[(R,R)-2]3(ClO4)2, there are two sets of three crystallographically independent donor molecules [(S,S)-2]2[(R,R)-2] in a unit cell, where the two sets are related by an inversion center. The latter α'-[(R,R)-2]ClO4(H2O) is the chiral salt with included solvent H2O, which is not isostructural with the reported chiral salt α'-[(S,S)-2]ClO4 without H2O, but has a similar donor arrangement. According to the molecular design by introduction of hydroxy groups and a ClO4 (-) anion, many intermediate-strength intermolecular hydrogen bonds (2.6-3.0 Å) were observed in these crystals between electron donor molecules, anions, and included H2O solvent, which improve the crystallinity and facilitate the extraction of physical properties. Both salts are semiconductors with relatively low resistivities at room temperature and activation energies of 1.2 ohm cm with E a = 86 meV for θ(21)-[(S,S)-2]3[(R,R)-2]3(ClO4)2 and 0.6 ohm cm with E a = 140 meV for α'-[(R,R)-2]2ClO4(H2O), respectively. The variety of donor arrangements, θ(21) and two kinds of α'-types, and their electrical conductivities of charge transfer complexes based upon the racemic and enantiopure (S,S)-2, and (R,R)-2 donors originates not only from the chirality, but also the introduced intermolecular hydrogen bonds involving the hydroxymethyl groups, perchlorate anion, and the included solvent H2O.

19.
Biomaterials ; 35(10): 3281-97, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24461327

RESUMEN

Acellular whole human lung scaffolds represent a unique opportunity for ex vivo tissue engineering. However, it remains unclear whether lungs from individuals with chronic lung diseases such as chronic obstructive pulmonary disease (COPD) can be appropriately decellularized and recellularized. To assess this, cadaveric human lungs from normal (non-smoking) patients and from patients with COPD (smoking history) were decellularized and found by histochemical and immunohistochemical staining, electron microscopy, and mass spectrometry to retain characteristic histological architecture and extracellular matrix components (ECM) reflecting either normal or COPD, particularly emphysematous, origin. Inoculation of human bronchial epithelial cells, endothelial progenitor cells, bone marrow-derived mesenchymal stem cells, and lung fibroblasts via airway or vascular routes into small, excised segments of the decellularized lungs demonstrated that normal lung scaffolds robustly supported initial engraftment and growth of each cell type for up to one month. In contrast, despite initial binding, all cell types inoculated into decellularized emphysematous lungs did not survive beyond one week. However, cell attachment and proliferation on solubilized ECM homogenates of decellularized normal and emphysematous lungs coated onto tissue culture plates was comparable and not impaired, suggesting that the 3-dimensional decellularized emphysematous scaffolds may lack the necessary ECM architecture to support sustained cell growth.


Asunto(s)
Enfisema/patología , Pulmón/patología , Línea Celular , Proteínas de la Matriz Extracelular/metabolismo , Humanos , Espectrometría de Masas , Microscopía Electrónica
20.
Genome Res ; 24(2): 310-7, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24307552

RESUMEN

Recent progress in next-generation sequencing has greatly facilitated our study of genomic structural variation. Unlike single nucleotide variants and small indels, many structural variants have not been completely characterized at nucleotide resolution. Deriving the complete sequences underlying such breakpoints is crucial for not only accurate discovery, but also for the functional characterization of altered alleles. However, our current ability to determine such breakpoint sequences is limited because of challenges in aligning and assembling short reads. To address this issue, we developed a targeted iterative graph routing assembler, TIGRA, which implements a set of novel data analysis routines to achieve effective breakpoint assembly from next-generation sequencing data. In our assessment using data from the 1000 Genomes Project, TIGRA was able to accurately assemble the majority of deletion and mobile element insertion breakpoints, with a substantively better success rate and accuracy than other algorithms. TIGRA has been applied in the 1000 Genomes Project and other projects and is freely available for academic use.


Asunto(s)
Componentes Genómicos , Variación Estructural del Genoma , Proyecto Genoma Humano , Programas Informáticos , Algoritmos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Análisis de Secuencia de ADN
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