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1.
Front Cardiovasc Med ; 10: 1220017, 2023.
Article in English | MEDLINE | ID: mdl-37719970

ABSTRACT

Icosapent ethyl (IPE) is a purified eicosapentaenoic acid-only omega-3 fatty acid that significantly reduced cardiovascular (CV) events in patients receiving statins with established cardiovascular disease (CVD) and those with diabetes and additional risk factors in the pivotal REDUCE-IT trial. Since the publication of REDUCE-IT, there has been global interest in determining IPE eligibility in different patient populations, the proportion of patients who may benefit from IPE, and cost effectiveness of IPE in primary and secondary prevention settings. The aim of this review is to summarize information from eligibility and cost effectiveness studies of IPE to date. A total of sixteen studies were reviewed, involving 2,068,111 patients in the primary or secondary prevention settings worldwide. Up to forty-five percent of patients were eligible for IPE, depending on the selection criteria used (ie, REDUCE-IT criteria, US Food and Drug Administration label, Health Canada label, practice guidelines) and the population studied. Overall, eight cost-effectiveness studies across the United States, Canada, Germany, Israel, and Australia were included in this review and findings indicated that IPE is particularly cost effective in patients with established CVD.

2.
J Am Chem Soc ; 145(13): 7659-7666, 2023 Apr 05.
Article in English | MEDLINE | ID: mdl-36952597

ABSTRACT

We report the direct time-domain observation of ultrafast dynamics driven by the Jahn-Teller effect. Using time-resolved photoelectron spectroscopy with a vacuum-ultraviolet femtosecond source to prepare high-lying Rydberg states of carbon tetrachloride, our measurements reveal the local topography of a Jahn-Teller conical intersection. The pump pulse prepares a configurationally mixed superposition of the degenerate 1T2 4p-Rydberg states, which then distorts through spontaneous symmetry breaking that we identify to follow the t2 bending motion. Photoionization of these states to three cationic states 2T1, 2T2, and 2E reveals a shift in the center-of-mass of the photoelectron peaks associated with the 2Tn states which reveals the local topography of the Jahn-Teller conical intersection region prepared by the pump pulse. Time-dependent density functional theory calculations confirm that the dominant nuclear motion observed in the spectrum is the CCl4 t2 bending mode. The large density of states in the VUV spectral region at 9.33 eV of carbon tetrachloride and strong vibronic coupling result in ultrafast decay of the excited-state signal with a time constant of 75(4) fs.

3.
Br J Clin Pharmacol ; 89(8): 2413-2422, 2023 08.
Article in English | MEDLINE | ID: mdl-36890711

ABSTRACT

AIMS: Dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) remains the standard of care. CYP2C19 genetic polymorphisms cause variable clopidogrel bioactivation. Increased function (CYP2C19*17) allele carriers (rapid metabolizers [RM] or ultrarapid metabolizers [UM]) are clopidogrel hyper-responders, hence are more susceptible to clopidogrel-related bleeding. Since current guidelines recommend against routine genotyping following PCI, data on the clinical utility of CYP2C19*17 genotype guided strategy are sparce. Our study provides real-world data on the 12-month follow-up of CYP2C19 genotyping in patients post-PCI. METHODS: This is a cohort study within an Irish population receiving 12-month DAPT following PCI. It identifies the prevalence of CYP2C19 polymorphisms within an Irish population and describes the ischaemic and bleeding outcomes after 12 months of DAPT. RESULTS: A total of 129 patients were included with the following CYP2C19 polymorphism prevalence: 30.2% hyper-responders (26.4% RM [1*/17*], 3.9% UM [17*/17*]) and 28.7% poor-responders (22.5% IM [1*/2*], 3.9% IM [2*/17*], 2.3% PM [2*/2*]). A total of 53 and 76 patients received clopidogrel and ticagrelor, respectively. At 12 months, total bleeding incidence within the clopidogrel group was positively correlated with CYP2C19 activity: IM/PM (0.0%), NM (15.0%) and RM/UM (25.0%). The positive relationship showed a moderate association that was statistically significant: rτ = 0.28, P = 0.035. CONCLUSIONS: The prevalence of CYP2C19 polymorphisms in Ireland is 58.9% (30.2% CYP2C19*17, 28.7% CYP2C19*2) with an approximately one in three chance of being a clopidogrel hyper-responder. Positive correlation between bleeding and increasing CYP2C19 activity within the clopidogrel group (n = 53) suggests possible clinical utility of a genotype-guided strategy identifying high bleeding risk with clopidogrel in CYP2C19*17 carriers, but further studies are required.


Subject(s)
Acute Coronary Syndrome , Percutaneous Coronary Intervention , Humans , Clopidogrel/adverse effects , Platelet Aggregation Inhibitors/adverse effects , Genotype , Cytochrome P-450 CYP2C19/genetics , Percutaneous Coronary Intervention/adverse effects , Cohort Studies , Hemorrhage/chemically induced , Hemorrhage/epidemiology , Hemorrhage/genetics , Acute Coronary Syndrome/drug therapy , Treatment Outcome
4.
Phys Chem Chem Phys ; 24(38): 23340-23349, 2022 Oct 05.
Article in English | MEDLINE | ID: mdl-36129030

ABSTRACT

Using vacuum-ultraviolet time-resolved velocity map imaging of photoelectrons, we study ultrafast coupled electronic and nuclear dynamics in low-lying Rydberg states of ammonia. Vibrationally-resolved internal vibrational relaxation (IVR) is observed in a progression of the e' bending modes. This vibrational progression is only observed in the D̃ state, and is lost upon ultrafast internal conversion to the C̃ and B̃ electronic states. Due to the ultrashort time scale of the internal conversion (ca. 64 fs), and the vibronic resolution, the non-adiabatic coupling vectors are identified and verified with ab initio calculations. The time-scale of this IVR process is highly surprising and significant because IVR is usually treated as an incoherent process that proceeds statistically, according to a "Fermi's Golden Rule"-like model, where the process scales with the available degrees of freedom. Here, we show that it can be highly non-statistical, restricted to only a very small subset of vibrational motions.

5.
Nat Chem ; 14(10): 1126-1132, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35953643

ABSTRACT

Directly contrasting ultrafast excited-state dynamics in the gas and liquid phases is crucial to understanding the influence of complex environments. Previous studies have often relied on different spectroscopic observables, rendering direct comparisons challenging. Here, we apply extreme-ultraviolet time-resolved photoelectron spectroscopy to both gaseous and liquid cis-stilbene, revealing the coupled electronic and nuclear dynamics that underlie its isomerization. Our measurements track the excited-state wave packets from excitation along the complete reaction path to the final products. We observe coherent excited-state vibrational dynamics in both phases of matter that persist to the final products, enabling the characterization of the branching space of the S1-S0 conical intersection. We observe a systematic lengthening of the relaxation timescales in the liquid phase and a red shift of the measured excited-state frequencies that is most pronounced for the complex reaction coordinate. These results characterize in detail the influence of the liquid environment on both electronic and structural dynamics during a complete photochemical transformation.

6.
Chemphyschem ; 23(24): e202200575, 2022 Dec 16.
Article in English | MEDLINE | ID: mdl-35969023

ABSTRACT

Single-photon ionisation of enantiopure methyl p-tolyl sulfoxide by circularly polarised light at 133 nm shows remarkably strong photoelectron circular dichroism (PECD), which has been measured in a velocity-map-imaging spectrometer. Both enantiomers were measured, each showing a PECD of a similar magnitude (ca. 25 %). These experiments were carried out with a tabletop high-harmonic source with a photon energy of 9.3 eV, capable of ionising the electronic ground state of most organic and inorganic molecules. Ab-initio scattering calculations provide a theoretical value of the expected chiral asymmetry parameter, and agree very well with the measured values once orbital mixing via configuration interaction in the cation is taken into account. This study demonstrates a simple photoionisation scheme that can be readily applied to study the time-resolved PECD of photochemical reactions and suggests a pronounced sensitivity of PECD to electronic configuration interaction in the cation.

7.
Sci Adv ; 8(28): eabq2811, 2022 Jul 15.
Article in English | MEDLINE | ID: mdl-35857523

ABSTRACT

Understanding the chirality of molecular reaction pathways is essential for a broad range of fundamental and applied sciences. However, the current ability to probe chirality on the time scale of primary processes underlying chemical reactions remains very limited. Here, we demonstrate time-resolved photoelectron circular dichroism (TRPECD) with ultrashort circularly polarized vacuum-ultraviolet (VUV) pulses from a tabletop source. We demonstrate the capabilities of VUV-TRPECD by resolving the chirality changes in time during the photodissociation of atomic iodine from two chiral molecules. We identify several general key features of TRPECD, which include the ability to probe dynamical chirality along the complete photochemical reaction path, the sensitivity to the local chirality of the evolving scattering potential, and the influence of electron scattering off dissociating photofragments. Our results are interpreted by comparison with high-level ab-initio calculations of transient PECDs from molecular photoionization calculations. Our experimental and theoretical techniques define a general approach to femtochirality.

8.
Opt Express ; 30(9): 14358-14367, 2022 Apr 25.
Article in English | MEDLINE | ID: mdl-35473180

ABSTRACT

The generation of ultrashort circularly polarized pulses in the extreme-ultraviolet spectral range has recently attracted considerable interest for applications in time-resolved circular-dichroism experiments. Here, we demonstrate a simple approach to generate near-circularly polarized femtosecond pulses in the vacuum-ultraviolet. The ellipticity of the generated light can be continuously tuned from linear to near-circular, as demonstrated by detailed polarimetry measurements. Combining optical polarimetry with photoelectron circular-dichroism (PECD) measurements, we demonstrate a novel approach to characterizing the polarization state of light in terms of all four Stokes parameters. For photon energies of 9.3 eV, we obtained S3 = 0.96 ± 0.02 and a degree of polarization of 97±2%, i.e. the highest values reported from any harmonic-generation source so far. This source is directly applicable to circular-dichroism experiments, also enabling time-resolved PECD in the extreme-ultraviolet, a general approach to probing time-dependent chirality during chemical processes on (sub)-femtosecond time scales.

9.
Ir J Med Sci ; 191(2): 553-558, 2022 Apr.
Article in English | MEDLINE | ID: mdl-33852156

ABSTRACT

BACKGROUND: Restrictions as a result of the COVID-19 pandemic have demanded an innovative approach to provide appropriate patient review. We have been running virtual cardiology clinics as per Health Service Executive guidance. AIMS: Our study aims to determine how virtual clinics change practice vs traditional clinics. METHODS: A retrospective cohort analysis was conducted on patients attending cardiology clinics in our hospital from 6 January to 13 March 2020 ('traditional clinic', n = 1644), compared with clinics during the COVID-19 outbreak, from 16 March to 22 April 2020 ('virtual clinic', n = 691), with the same medical staff. RESULTS: There was no difference in age (61 vs 60), case mix or new vs return appointments in virtual vs traditional clinics. There were similar rates of clinic participation, 71.8% vs 74.2%. A lower proportion of investigations (e.g. imaging) were booked in virtual (38.5%) vs traditional (55.7%) clinics, p < 0.00001. Management changes (e.g. medication changes) were less frequent in virtual (19.9%) vs traditional (38.5%) clinics, p < 0.00001. However, the discharge rate was higher in virtual (28.8%) vs traditional (19.5%) clinics, p = 0.00003. CONCLUSION: This study highlights that virtual clinic consultations are associated with fewer investigations, fewer management changes, and increased discharge rates compared with traditional consultations. These practice changes would reduce costs and hospital outpatient congestion by avoiding unnecessary hospital reviews. Nonetheless, it is unknown whether patients requiring face-to-face consultations could be missed as a result of this virtual approach. Longitudinal studies are required to assess clinical outcomes as a result of these practice changes and whether patient satisfaction is altered.


Subject(s)
COVID-19 , Cardiology , Telemedicine , Ambulatory Care Facilities , Humans , Pandemics , Retrospective Studies , SARS-CoV-2 , Telemedicine/methods
10.
J Phys Chem Lett ; 12(38): 9220-9225, 2021 Sep 30.
Article in English | MEDLINE | ID: mdl-34529447

ABSTRACT

Excited-state chemistry lacks generalized symmetry rules. With many femtochemistry studies focused on individual cases, it is hard to build up the same level of chemical intuition for excited states as that for ground states. Here, we unravel the degrees of freedom involved in ultrafast internal conversion (IC) by mapping the vibrational coherence of the initial wavepacket and the dependence on molecular symmetry in various cyclic tertiary amines. Molecular symmetry plays an important role in the preservation of vibrational coherence in the transit from one electronic state to another. We show here that it is sufficient for the molecule to simply have the possibility of a more symmetric structure to achieve the preservation of vibrational coherence. It can be transient and still lead to preservation. This finding provides an additional angle on how symmetry influences electronic transitions and an additional piece to the puzzle of establishing symmetry-based selection rules for excited-state processes.

11.
J Cardiovasc Pharmacol Ther ; 26(1): 67-74, 2021 01.
Article in English | MEDLINE | ID: mdl-32783474

ABSTRACT

BACKGROUND: Limited data are available regarding real-world prescribing in patients with an indication for oral anticoagulation (OAT) who undergo percutaneous coronary intervention (PCI). Most current guidelines recommend a period of triple therapy with OAT and dual antiplatelet (DAPT) agents over dual therapy with an OAT and DAPT but the clinical benefit is still unclear giving rise to limited evidence-based recommendations. AIM: To analyze the appropriateness of OAT and anti-platelet strategies post PCI in a real-world cohort of patients in 2 academic teaching hospitals. METHODS AND RESULTS: In total, 103 patients were retrospectively analyzed. As the initial 3 month stragey, 97 patients (94.2%) received triple therapy, 4 received Dual Therapy (3.9%) and 2 received DAPT (1.9%). Patients with predominant bleeding risk were significantly less likely to receive triple therapy (75% vs. 95.7% vs. 95.8%, P < 0.05). Apixaban was the most common OAT (65.7%) which in most cases was prescribed at an inappropriately reduced dose of 2.5 mg BD (80.4%). The MACE, bleeding and all-cause mortality rates did not differ significantly between groups. DISCUSSION: Our study demonstrates the widespread use of triple therapy for the first 3 months of treatment in 2 Irish academic hospitals. DOACs were prescribed in most cases at reduced doses not currently known to prevent stroke. This study highlights the need for more explicit management algorithms to improve evidence-based management in this area.


Subject(s)
Anticoagulants/administration & dosage , Coronary Artery Disease/therapy , Percutaneous Coronary Intervention , Platelet Aggregation Inhibitors/administration & dosage , Practice Patterns, Physicians'/trends , Administration, Oral , Aged , Aged, 80 and over , Anticoagulants/adverse effects , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/mortality , Drug Administration Schedule , Drug Utilization/trends , Dual Anti-Platelet Therapy , Female , Humans , Ireland , Male , Middle Aged , Percutaneous Coronary Intervention/adverse effects , Percutaneous Coronary Intervention/mortality , Platelet Aggregation Inhibitors/adverse effects , Retrospective Studies , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome
12.
Br J Cardiol ; 27(2): 13, 2020.
Article in English | MEDLINE | ID: mdl-35747087
13.
J Chem Phys ; 151(10): 104306, 2019 Sep 14.
Article in English | MEDLINE | ID: mdl-31521079

ABSTRACT

Time-resolved dynamics of high-lying Rydberg states of ammonia (NH3) prepared by using a vacuum ultraviolet (VUV) pump (∼9.3 eV) and an ultraviolet (UV) probe (∼4.7 eV) pulse are reported using photoelectron imaging detection. After photoexcitation, two main features appear in the photoelectron spectrum with vertical binding energies of ∼1.8 eV and ∼3.2 eV and with distinctly different anisotropy parameters ß of ∼1.3 and ∼0.7, respectively. This information allows the unambiguous assignment of the respective Rydberg states and disentangles the induced electronic and vibrational dynamics. The combination of velocity-map imaging with femtosecond VUV and UV pulses is shown to offer an attractive approach for studying the dynamics of high-lying Rydberg states of small molecules.

14.
Phys Chem Chem Phys ; 21(5): 2283-2294, 2019 Jan 30.
Article in English | MEDLINE | ID: mdl-30397704

ABSTRACT

Symmetry effects in internal conversion are studied by means of two isomeric cyclic tertiary aliphatic amines in a velocity map imaging (VMI) experiment on the femtosecond timescale. It is demonstrated that there is a delicate structural dependence on when coherence is preserved after the transition between the 3p and 3s Rydberg states. N-Methyl morpholine (NMM) shows unambiguous preserved coherence, consistent with previous work, which is decidedly switched off by the repositioning of oxygen within the ring. From the differences in these dynamics, and an examination of the potential energy surface following the normal modes of vibration, it becomes clear that there is a striking dependence on atom substitution, which manifests itself in the permitted modes of vibration that take the system out of the Franck-Condon region through to the 3s minimum. It is shown that the non Fermi-like behaviour of NMM is due to a conical intersection (CI) between the 3px and 3s states lying directly along the symmetry allowed path of steepest descent out of the Franck-Condon region. NMI, where the symmetry has been changed, is shown to undergo internal conversion in a more Fermi-like manner as the energy spreads through the available modes ergodically.

15.
J Phys Chem Lett ; 9(22): 6556-6562, 2018 Nov 15.
Article in English | MEDLINE | ID: mdl-30380873

ABSTRACT

Identification of the initially prepared, optically active state remains a challenging problem in many studies of ultrafast photoinduced processes. We show that the initially excited electronic state can be determined using the anisotropic component of ultrafast time-resolved X-ray scattering signals. The concept is demonstrated using the time-dependent X-ray scattering of N-methyl morpholine in the gas phase upon excitation by a 200 nm linearly polarized optical pulse. Analysis of the angular dependence of the scattering signal near time zero renders the orientation of the transition dipole moment in the molecular frame and identifies the initially excited state as the 3p z Rydberg state, thus bypassing the need for further experimental studies to determine the starting point of the photoinduced dynamics and clarifying inconsistent computational results.

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