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1.
J Clin Epidemiol ; 158: 92-98, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36965599

RESUMO

OBJECTIVES: Assess the impact of the Health Research Board (HRB) Ireland guidance on the uptake of core outcome sets (COSs). STUDY DESIGN AND SETTING: (1) Information on COS use, searching of the Core Outcome Measures in Effectiveness Trials (COMET) database, and rationale for outcome selection were extracted from HRB funding applications (2) COMET was searched for relevant COS availability at the time of application or developed since (3) principal investigator choices were explored through online surveys. RESULTS: Out of 187 funding applications, 44% (n = 82) searched the COMET database, and 13% (n = 11) of those found a relevant COS to inform their outcomes. Four applicants proposed COS development. However, 84% (n = 156) of applications had no relevant COS available at the time of submission, as identified by subsequent author COMET search. Among 84 principal investigators who participated in the surveys, 10 (12%) found and used a COS and 19 (42%) of the 45 respondents who did not have reference to COMET had searched the COMET database. A new question in the application form prompted a rise in those reporting a search of the COMET database from 6% to 99%. CONCLUSION: The study found low COS uptake in funding applications, but a new application question prompted an increase in reporting searches of the COMET database. Funder guidance promoted COS awareness and use, but more efforts are needed to facilitate COS development and adoption in clinical research.


Assuntos
Avaliação de Resultados em Cuidados de Saúde , Projetos de Pesquisa , Humanos , Inquéritos e Questionários , Resultado do Tratamento , Técnica Delphi
2.
Photochem Photobiol Sci ; 10(8): 1355-64, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21698328

RESUMO

The transient species formed following excitation of fac-[Re(CO)(3)(F(2)dppz)(py)](+) (F(2)dppz = 11,12-difluorodipyrido[3,2-a:2',3'-c]phenazine) bound to double-stranded polynucleotides [poly(dA-dT)](2) or [poly(dG-dC)](2) have been studied by transient visible and infra-red spectroscopy in both the picosecond and nanosecond time domains. The latter technique has been used to monitor both the metal complex and the DNA by monitoring the regions 1900-2100 and 1500-1750 cm(-1) respectively. These data provide direct evidence for electron transfer from guanine to the excited state of the metal complex, which proceeds both on a sub-picosecond time scale and with a lifetime of 35 ps, possibly due to the involvement of two excited states. No electron transfer is found for the [poly(dA-dT)](2) complex, although characteristic changes are seen in the DNA-region TRIR consistent with changes in the binding of the bases in the intercalation site upon excitation of the dppz-complex.


Assuntos
Complexos de Coordenação/química , Substâncias Intercalantes/química , Fenazinas/química , Poli dA-dT/química , Polidesoxirribonucleotídeos/química , Rênio/química , Absorção , Pareamento de Bases , Transporte de Elétrons , Teoria Quântica , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Fatores de Tempo
3.
Chemistry ; 14(1): 369-75, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17886324

RESUMO

Transient species formed by photoexcitation (400 nm) of [Ru(dppz)(tap)2]2+ (1) (dppz = dipyrido[3,2-a:2',3'-c]phenazine; tap=1,4,5,8-tetraazaphenanthrene) in aqueous solution and when intercalated into a double-stranded synthetic polynucleotide, [poly(dG-dC)]2, have been observed on a picosecond timescale by both visible transient absorption (allowing monitoring of the metal complex intermediates) and transient infrared (IR) absorption spectroscopy (allowing direct study of the DNA nucleobases). By contrast with its behavior when free in aqueous solution, excitation of 1 when bound to [poly(dG-dC)]2 causes a strong increase in absorbance at 515 nm due to formation of the reduced complex [Ru(dppz)(tap)2]+ (rate constant=(2.0+/-0.2) x 10(9) s(-1)). The subsequent reformation of 1 proceeds with a rate constant of (1.1+/-0.2) x 10(8) s(-1). When the process is carried out in D2O, the rates of formation and removal of [Ru(dppz)(tap)2]+ are reduced (rate constants (1.5+/-0.3) x 10(9) and (0.7+/-0.2) x 10(8) s(-1) respectively) consistent with proton-coupled electron transfer processes. Picosecond transient IR measurements in the 1540-1720 cm(-1) region in D2O solution confirm that the reduction of 1 intercalated into [poly(dG-dC)]2 is accompanied by bleaching of IR ground-state bands of guanine (1690 cm(-1)) and cytosine (1656 cm(-1)), each with similar rate constants.


Assuntos
Guanina/química , Fenazinas/química , Polinucleotídeos/química , Compostos de Rutênio/química , Estrutura Molecular , Oxirredução , Fotoquímica , Espectrofotometria Infravermelho , Fatores de Tempo
4.
Photochem Photobiol Sci ; 6(7): 741-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17609767

RESUMO

The photophysical properties of [Re(CO)(3)(dppz)(py)](+) (dppz = dipyrido-[3,2-a:2',3'-c] phenazine) and its 11,12 substituted derivatives [Re(CO)(3)(dppzMe(2))(py)](+) and [Re(CO)(3)(dppzF(2))(py)](+) have been examined in organic and aqueous environments using phosphorescence and picosecond transient visible and infrared absorption spectroscopic methods. The roles of the intraligand IL(pi-pi*) and metal-to-ligand charge transfer MLCT(phz) excited states are evaluated and used to explain the major effect of difluoro-substitution, which is particularly remarkable in water, where the excited state of [Re(CO)(3)(dppzF(2))(py)](+) is strongly quenched.

5.
Anal Chem ; 77(8): 2564-8, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15828794

RESUMO

Living cells survive environmentally stressful conditions by initiating a stress response. We monitored changes in the Raman spectra of optically trapped Saccharomyces cerevisiae yeast cell under normal, heat-treated, and hyperosmotic stress conditions. It is shown that when glucose was used to exert hyperosmotic stress, two chemical substances-glycerol and ethanol-can be monitored in real time in a single cell.


Assuntos
Etanol/análise , Glicerol/análise , Pinças Ópticas , Saccharomyces cerevisiae/fisiologia , Análise Espectral Raman/métodos , Temperatura Alta , Óptica e Fotônica , Pressão Osmótica
6.
Opt Express ; 13(16): 6105-10, 2005 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-19498620

RESUMO

Raman imaging can yield spatially resolved biochemical information from living cells. To date there have been no Raman images published of cells in suspension because of the problem of immobilizing them suitably to acquire space-resolved spectra. In this paper in order to overcome this problem the use of holographic optical tweezers is proposed and implemented, and data is shown for spatially resolved Raman spectroscopy of a live cell in suspension.

7.
Photochem Photobiol Sci ; 2(5): 542-54, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12803077

RESUMO

The photophysical properties of fac-[Re(CO)3(dppz)(py)]+ (1, where dppz = dipyrido[3,2-a: 2',3'-c]phenazine) in CH3CN have been investigated using a series of complementary techniques including visible and infrared transient absorption and resonance Raman spectroscopy on the picosecond and nanosecond timescales. The results confirm previous reports that the lowest-lying emissive state in 1 is a triplet intra-ligand (3IL) state localised on the dppz ligand and have provided detailed information on the dynamics of 1 upon photoexcitation, including the relative energies of the excited state species encountered and the electronic distribution within these. If the dppz ligand is viewed in terms of phenanthroline (phen) and phenazine (phz) moieties, the emissive state is probably more accurately described as a 3 pi-->pi *(phz) IL state. The picosecond studies have shown that this emissive state is formed, at least in part, within 30 ps of excitation from a precursor, which is possibly a 3 pi-->pi *(phen) IL state. On the nanosecond timescale, TRIR has been employed to elucidate further dynamics and reveal the presence of an energetically close-lying state in equilibrium with the emissive state. This has tentatively been assigned as being 3d pi(Re)-->pi *(phz) metal-to-ligand charge transfer (MLCT) in nature. A summary of the photophysics is proposed in the form of a Jablonski scheme. Time dependent density functional theory (TD-DFT) calculations support the relative ordering and suggested electronic character of the excited state species involved.

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