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1.
Int J Gynecol Cancer ; 30(5): 695-700, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32312719

RESUMEN

The National Cancer Survivorship Initiative through the National Health Service (NHS) improvement in the UK started the implementation of stratified pathways of patient-initiated follow-up (PIFU) across various tumor types. Now the initiative is continued through the Living With and Beyond Cancer program by NHS England. Evidence from non-randomized studies and systematic reviews does not demonstrate a survival advantage to the long-established practice of hospital-based follow-up regimens, traditionally over 5 years. Evidence shows that patient needs are inadequately met under the traditional follow-up programs and there is therefore an urgent need to adapt pathways to the needs of patients. The assumption that hospital-based follow-up is able to detect cancer recurrences early and hence improve patient prognosis has not been validated. A recent survey demonstrates that follow-up practice across the UK varies widely, with telephone follow-up clinics, nurse-led clinics and PIFU becoming increasingly common. There are currently no completed randomized controlled trials in PIFU in gynecological malignancies, although there is a drive towards implementing PIFU. PIFU aims to individualize patient care, based on risk of recurrence and holistic needs, and optimizing resources. The British Gynaecological Cancer Society wishes to provide the gynecological oncology community with guidance and a recommendations statement regarding the value, indications, and limitations of PIFU in endometrial, cervical, ovarian, and vulvar cancers in an effort to standardize practice and improve patient care.


Asunto(s)
Neoplasias de los Genitales Femeninos/diagnóstico , Participación del Paciente , Femenino , Preservación de la Fertilidad , Estudios de Seguimiento , Humanos , Recurrencia Local de Neoplasia/diagnóstico
2.
Biomacromolecules ; 16(10): 3217-25, 2015 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-26388289

RESUMEN

Detection of specific RNA or DNA molecules by hybridization to "probe" nucleic acids via complementary base-pairing is a powerful method for analysis of biological systems. Here we describe a strategy for transducing hybridization events through modulating intrinsic properties of the electroconductive polymer polyaniline (PANI). When DNA-based probes electrostatically interact with PANI, its fluorescence properties are increased, a phenomenon that can be enhanced by UV irradiation. Hybridization of target nucleic acids results in dissociation of probes causing PANI fluorescence to return to basal levels. By monitoring restoration of base PANI fluorescence as little as 10(-11) M (10 pM) of target oligonucleotides could be detected within 15 min of hybridization. Detection of complementary oligos was specific, with introduction of a single mismatch failing to form a target-probe duplex that would dissociate from PANI. Furthermore, this approach is robust and is capable of detecting specific RNAs in extracts from animals. This sensor system improves on previously reported strategies by transducing highly specific probe dissociation events through intrinsic properties of a conducting polymer without the need for additional labels.


Asunto(s)
Concentración de Iones de Hidrógeno
3.
Biomacromolecules ; 12(6): 2416-28, 2011 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-21561167

RESUMEN

Novel highly functional biobased epoxy compounds, epoxidized sucrose esters of fatty acids (ESEFAs), were cross-linked with a liquid cycloaliphatic anhydride to prepare polyester thermosets. The degree of cure or conversion was studied using differential scanning calorimetry (DSC), and the sol content of the thermosets was determined using solvent extraction. The mechanical properties were studied using tensile testing to determine Young's modulus, tensile stress, and elongation at break. Dynamic mechanical analysis (DMA) was used to determine glass-transition temperature, storage modulus, and cross-link density. The nanomechanical properties of the surfaces were studied using nanoindentation to determine reduced modulus and indentation hardness. The properties of coatings on steel substrates were studied to determine coating hardness, adhesion, solvent resistance, and mechanical durability. Compared with the control, epoxidized soybean oil, the anhydride-cured ESEFAs have high modulus and are hard and ductile, high-performance thermoset materials while maintaining a high biobased content (71-77% in theory). The exceptional performance of the ESEFAs is attributed to the unique structure of these macromolecules: well-defined compact structures with high epoxide functionality. These biobased thermosets have potential uses in applications such as composites, adhesives, and coatings.


Asunto(s)
Materiales Biocompatibles Revestidos/síntesis química , Compuestos Epoxi/síntesis química , Ácidos Grasos/química , Poliésteres/síntesis química , Sacarosa/química , Anhídridos/química , Rastreo Diferencial de Calorimetría , Reactivos de Enlaces Cruzados/química , Módulo de Elasticidad , Elasticidad , Dureza , Ensayo de Materiales , Mecánica , Solventes , Aceite de Soja/química , Espectroscopía Infrarroja por Transformada de Fourier , Acero , Propiedades de Superficie , Temperatura , Resistencia a la Tracción
4.
J Vis Exp ; (117)2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27842355

RESUMEN

Detection of nucleic acids is at the center of diagnostic technologies used in research and the clinic. Standard approaches used in these technologies rely on enzymatic modification that can introduce bias and artifacts. A critical element of next generation detection platforms will be direct molecular sensing, thereby avoiding a need for amplification or labels. Advanced nanomaterials may provide the suitable chemical modalities to realize label-free sensors. Conjugated polymers are ideal for biological sensing, possessing properties compatible with biomolecules and exhibit high sensitivity to localized environmental changes. In this article, a method is presented for detecting nucleic acids using the electroconductive polymer polyaniline. Simple DNA "probe" oligonucleotides complementary to target nucleic acids are attached electrostatically to the polymer, creating a sensor system that can differentiate single nucleotide differences in target molecules. Outside the specific and unbiased nature of this technology, it is highly cost effective.


Asunto(s)
Técnicas Biosensibles , Ácidos Nucleicos , ADN , Nanoestructuras , Oligonucleótidos
5.
Biochem Biophys Rep ; 4: 312-323, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29124219

RESUMEN

The X-ray diffraction and spectroscopic properties of 1-amino-4-hydroxy-9,10-anthraquinone (1-AHAQ), a simple analogue of anthracycline chemotherapeutic drugs were studied by adopting experimental and computational methods. The optimized geometrical parameters obtained from computational methods were compared with the results of X-ray diffraction analysis and the two were found to be in reasonably good agreement. X-ray diffraction study, Density Functional Theory (DFT) and natural bond orbital (NBO) analysis indicated two types of hydrogen bonds in the molecule. The IR spectra of 1-AHAQ were studied by Vibrational Energy Distribution Analysis (VEDA) using potential energy distribution (PED) analysis. The electronic spectra were studied by TDDFT computation and compared with the experimental results. Experimental and theoretical results corroborated each other to a fair extent. To understand the biological efficacy of 1-AHAQ, it was allowed to interact with calf thymus DNA and human breast adino-carcinoma cell MDA-MB-231. It was found that the molecule induces apoptosis in this adinocarcinoma cell, with little, if any, cytotoxic effect in HBL-100 normal breast epithelial cell.

6.
Dalton Trans ; 44(12): 5428-40, 2015 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-25691434

RESUMEN

A 1 : 2 copper(II) complex of 1-amino-4-hydroxy-9,10-anthraquinone (QH) having the molecular formula CuQ2 was prepared and characterized by elemental analysis, NMR, FTIR, UV-vis and mass spectroscopy. The powder diffraction of the solid complex, magnetic susceptibility and ESR spectra were also recorded. The presence of the planar anthraquinone moiety in the complex makes it extremely difficult to obtain a single crystal suitable for X-ray diffraction studies. To overcome this problem, density functional theory (DFT) was used to evaluate an optimized structure of CuQ2. In the optimized structure, it was found that there is a tilt of the two planar aromatic anthraquinone rings of the complex with respect to each other in the two planes containing the O-Cu(II)-O plane. The present study is an important addition to the understanding of the structural aspects of metal-anthracyclines because there are only a few reports on the actual structures of metal-anthracyclines. The theoretical vibrational spectrum of the complex was assigned with the help of vibrational energy distribution analysis (VEDA) using potential energy distribution (PED) and compared with experimental results. Being important in producing the biochemical action of this class of molecules, the electrochemical behavior of the complex was studied in aqueous and non-aqueous solvents to find certain electrochemical parameters. In aqueous media, reduction involves a kinetic effect during electron transfer at an electrode surface, which was characterized very carefully using cyclic voltammetry. Electrochemical studies showed a significant modification in the electrochemical properties of 1-amino-4-hydroxy-9,10-anthraquinone (QH) when bound to Cu(II) in the complex compared to those observed for free QH. This suggests that the copper complex might be a good choice as a biologically active molecule, which was reflected in the lack of stimulated superoxide generation by the complex.


Asunto(s)
Antraquinonas/química , Complejos de Coordinación/química , Cobre/química , NADH Deshidrogenasa/metabolismo , Superóxidos/metabolismo , Aminación , Antraquinonas/farmacología , Complejos de Coordinación/farmacología , Cobre/farmacología , Humanos , Modelos Moleculares , Análisis Espectral , Difracción de Rayos X
7.
Surg Oncol ; 19(4): e150-4, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20833535

RESUMEN

INTRODUCTION: Restricting inguinofemoral lymphadenectomy to patients with malignant nodes would reduce treatment-related morbidity in vulval cancer patients. A prospective study was conducted to determine the diagnostic accuracy of the Sentinel Lymph Node (SLN) procedure in vulval cancer patients referred following either diagnostic or excision biopsy. METHODS: Patients with clinical stage I and II squamous cell carcinoma of the vulva underwent SLN identification with peri-scar/lesional injection of (99m)Technetium-labelled nanocolloid (pre-operative lymphoscintigraphy and intra-operative use of a hand-held probe) and intra-operative blue dye. Radical excision of the vulval tumour or scar and formal inguinofemoral lymphadenectomy was then performed as necessary. SLN were processed separately and further examined at multiple levels to exclude micrometastases (H&E/cytokeratin staining) if negative on routine analysis. Clinical follow-up was carried out to identify and treat recurrences or treatment-related morbidity. RESULTS: Thirty-two women took part. Fifteen were referred following excision biopsy and seventeen following diagnostic biopsy of their primary vulval tumour. One or more SLN was successfully detected intra-operatively in 31 patients (97%) and 45 groins. An SLN could not be identified intra-operatively in one case (re-excision of scar). On average, more SLN were identified in patients with their primary vulval lesion in situ compared with those whose tumour had previously been excised (2.6 vs. 1.8, p = 0.03). Midline tumours were more likely (15/17) than lateral tumours (1/15) to have bilateral SLN identified pre-operatively. Two patients with midline tumours previously excised had unilateral SLN. Seven patients (23%) and ten groins had inguinofemoral lymph node metastases. The SLN procedure correctly identified inguinofemoral metastases in six patients (nine groins). In one case (midline tumour, re-excision of scar) the sentinel node was positive on one side but false negative on the other. CONCLUSIONS: The SLN procedure may be used to identify malignant groins in selected patients with vulval cancer. The extent to which previous vulval surgery might influence the accuracy of the SLN procedure deserves further investigation.


Asunto(s)
Carcinoma de Células Escamosas/patología , Biopsia del Ganglio Linfático Centinela/métodos , Neoplasias de la Vulva/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/cirugía , Reacciones Falso Negativas , Femenino , Ingle/patología , Humanos , Escisión del Ganglio Linfático , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Neoplasias de la Vulva/cirugía
8.
J Chem Phys ; 124(7): 74511, 2006 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-16497061

RESUMEN

The water exchange process of square planar tetraaquaplatinum(II) was computationally investigated at the Hartree-Fock, density-functional theory (B3LYP, PW91PW91, and mPW1PW91) and the second-order Moller-Plesset perturbation theory of levels of calculation. The stationary points on the gas phase and on the reaction field potential-energy surface were fully optimized and characterized. The self-consistent reaction field (SCRF) methods were also applied on the same system. The structures and energetic processes of all the species involved were investigated. The kinetic and thermodynamic properties for the gas phase and SCRF model data were compared with the available experimental data. The rate constants in MP2 level of theory and B3LYP isodensity polarized continuum model reaction field are in good agreement with the experimental data.

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