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1.
Opt Express ; 28(26): 38813-38821, 2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33379441

RESUMEN

A novel configuration of a Fourier domain mode locked (FDML) laser based on silicon photonics platform is presented in this work that exploits the narrowband reflection spectrum of a photonic crystal (PhC) cavity resonator. Configured as a linear Fabry-Perot laser, forward biasing of a p-n junction on the PhC cavity allowed for thermal tuning of the spectrum. The modulation frequency applied to the reflector equalled the inverse roundtrip time of the long cavity resulting in stable FDML operation over the swept wavelength range. An interferometric phase measurement measured the sweeping instantaneous frequency of the laser. The silicon photonics platform has potential for very compact implementation, and the electro-optic modulation method opens the possibility of modulation speeds far beyond those of mechanical filters.

2.
Org Biomol Chem ; 10(44): 8911-8, 2012 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-23051910

RESUMEN

Backbone-fluorinated amino acids exhibit unique conformational behaviour, and have potential utility as components of bioactive shape-controlled peptides. However, methods for the elaboration of backbone-fluorinated amino acids have thus far been limited to solution phase peptide coupling reactions. In this paper, protocols are developed that allow the successful manipulation of backbone-fluorinated amino acids using Fmoc-strategy solid phase peptide synthesis. To exemplify this strategy, several fluorinated RGD peptide analogues were synthesised in moderate to good overall yields.


Asunto(s)
Aminoácidos/química , Péptidos/síntesis química , Técnicas de Síntesis en Fase Sólida/métodos , Aminoácidos/síntesis química , Halogenación , Oligopéptidos/síntesis química , Oligopéptidos/química , Péptidos/química
3.
Nanophotonics ; 11(18): 4183-4196, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36147699

RESUMEN

In this paper we show a novel design of high Q-factor silicon nitride (SiN) 1D photonic crystal (PhC) cavities side-coupled to curved waveguides, operating with both silica and air cladding. The engineering of the etched 1D PhC cavity sidewalls angle allows for high Q-factors over a wide range of upper cladding compositions, and the achievement of the highest calculated Q-factor for non-suspended asymmetric SiN PhC structures. We show the employment of these type of SiN PhC cavities in hybrid external cavity laser (HECL) configuration, with mode-hop free single mode laser operation over a broad range of injected currents (from 25 mA to 65 mA), milliwatts of power output (up to 9 mW) and side-mode suppression ratios in the range of 40 dB. We demonstrate the operation of these devices as compact and energy efficient optical sensors that respond to refractive index changes in the surrounding medium the measurement of sodium chloride (from 0% to 25%) and sucrose (from 0% to 25%) in aqueous solution. In HECL configuration, the RI sensor exhibits a 2 orders of magnitude improvement in detection limit compared to the passive microcavity. We also discuss the possibility for applying these devices as novel transducers for refractive index changes that are induced by analyte specific absorption of infrared radiation by the target analytes present in gas or liquid phase.

4.
J Neurol Neurosurg Psychiatry ; 82(6): 594-600, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21172856

RESUMEN

BACKGROUND: There is very limited evidence for the efficacy of any specific therapeutic intervention in chronic, treatment refractory major depression. Thermal anterior capsulotomy (ACAPS) is a rarely performed but established therapeutic procedure for this patient group. While benefit has been claimed, previous ACAPS reports have provided limited information. Detailed prospective reporting of therapeutic effects and side effects is required. OBJECTIVE: To report a prospective study of therapeutic effect, mental status, quality of life, social functioning and neurocognitive functioning in individuals with chronic treatment refractory major depression, treated with ACAPS. METHOD: A prospective case series of 20 patients treated with ACAPS between 1992 and 1999 were reassessed at a mean follow-up of 7.0±3.4 years. Data were collected preoperatively and at long term follow-up. Structural MRI was performed in 14 participants. RESULTS: According to a priori criteria, at long term follow-up, 50% were classified as 'responders' and 40% as 'remitters'. Fifty-five per cent were classified as 'improved'; 35% were 'unchanged'; and 10% had 'deteriorated'. Neurocognitive and personality testing were not significantly different at follow-up. A trend towards improvement in some aspects of executive neuropsychological functioning was observed. Significant adverse effects were infrequent and there were no deaths. CONCLUSIONS: ACAPS may represent an effective intervention for some patients with chronic, disabling, treatment refractory major depression that has failed to respond to other therapeutic approaches. The adverse effect burden within this population was modest, with no evidence of generalised impairment of neurocognitive functioning.


Asunto(s)
Trastorno Depresivo Mayor/cirugía , Cápsula Interna/cirugía , Complicaciones Posoperatorias , Psicocirugía/métodos , Adulto , Trastorno Depresivo Mayor/psicología , Resistencia a Medicamentos , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Determinación de la Personalidad , Estudios Prospectivos , Psicocirugía/efectos adversos , Calidad de Vida/psicología , Resultado del Tratamiento
7.
J Med Chem ; 62(19): 8796-8808, 2019 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-31497959

RESUMEN

The heterodimeric transmembrane αv integrin receptors have recently emerged as potential targets for the treatment of idiopathic pulmonary fibrosis. Herein, we describe how subtle modifications of the central aromatic ring of a series of phenylbutyrate-based antagonists of the vitronectin receptors αvß3 and αvß5 significantly change the biological activities against αvß6 and αvß8. This resulted in the discovery of a pan αv antagonist (compound 39, 4-40 nM for the integrin receptors named above) possessing excellent oral pharmacokinetic properties in rats (with a clearance of 7.6 mL/(min kg) and a bioavailability of 97%).


Asunto(s)
Fibrosis Pulmonar Idiopática/patología , Integrina alfaV/química , Fenilbutiratos/química , Administración Oral , Animales , Antígenos de Neoplasias/metabolismo , Sitios de Unión , Cristalografía por Rayos X , Evaluación Preclínica de Medicamentos , Semivida , Humanos , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Fibrosis Pulmonar Idiopática/metabolismo , Integrina alfaV/metabolismo , Integrina alfaVbeta3/antagonistas & inhibidores , Integrina alfaVbeta3/metabolismo , Integrinas/antagonistas & inhibidores , Integrinas/metabolismo , Conformación Molecular , Simulación del Acoplamiento Molecular , Fenilbutiratos/farmacocinética , Fenilbutiratos/uso terapéutico , Estructura Terciaria de Proteína , Ratas , Receptores de Vitronectina/antagonistas & inhibidores , Receptores de Vitronectina/metabolismo , Relación Estructura-Actividad
8.
Bioorg Med Chem Lett ; 18(24): 6423-8, 2008 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-18980843

RESUMEN

High-throughput screening resulted in the identification of a series of novel motilin receptor agonists with relatively low molecular weights. The series originated from an array of biphenyl derivatives designed to target 7-transmembrane (7-TM) receptors. Further investigation of the structure-activity relationship within the series resulted in the identification of compound (22) as a potent and selective agonist at the motilin receptor.


Asunto(s)
Receptores de la Hormona Gastrointestinal/agonistas , Receptores de la Hormona Gastrointestinal/química , Receptores de Neuropéptido/agonistas , Receptores de Neuropéptido/química , Animales , Sitios de Unión , Membrana Celular/metabolismo , Química Farmacéutica/métodos , Técnicas Químicas Combinatorias , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Humanos , Modelos Químicos , Estructura Molecular , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Recombinantes/química , Relación Estructura-Actividad
11.
Waste Manag Res ; 26(3): 233-40, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18649570

RESUMEN

Changes in environmental legislation and standards governing healthcare waste, such as the Hazardous Waste Regulations are expected to have a significant impact on healthcare waste quantities and costs in England and Wales. This paper presents findings from two award winning case study organizations, the Cardiff and Vale NHS Trust and the Cornwall NHS Trust on 'systems' they have employed for minimizing waste. The results suggest the need for the development and implementation of a holistic range of systems in order to develop best practice, including waste minimization strategies, key performance indicators, and staff training and awareness. The implications for the sharing of best practice from the two case studies are also discussed.


Asunto(s)
Benchmarking , Eliminación de Residuos Sanitarios/normas , Inglaterra , Eliminación de Residuos Sanitarios/métodos , Medicina Estatal , Reino Unido , Gales
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