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1.
Faraday Discuss ; 248(0): 381-391, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-37846514

RESUMO

The lithium-air (Li-air) battery offers one of the highest practical specific energy densities of any battery system at >400 W h kgsystem-1. The practical cell is expected to operate in air, which is flowed into the positive porous electrode where it forms Li2O2 on discharge and is released as O2 on charge. The presence of CO2 and H2O in the gas stream leads to the formation of oxidatively robust side products, Li2CO3 and LiOH, respectively. Thus, a gas handling system is needed to control the flow and remove CO2 and H2O from the gas supply. Here we present the first example of an integrated Li-air battery with in-line gas handling, that allows control over the flow and composition of the gas supplied to a Li-air cell and simultaneous evaluation of the cell and scrubber performance. Our findings reveal that O2 flow can drastically impact the capacity of cells and confirm the need for redox mediators. However, we show that current air-electrode designs translated from fuel cell technology are not suitable for Li-air cells as they result in the need for higher gas flow rates than required theoretically. This puts the scrubber under a high load and increases the requirements for solvent saturation and recapture. Our results clarify the challenges that must be addressed to realise a practical Li-air system and will provide vital insight for future modelling and cell development.

2.
J Am Chem Soc ; 145(16): 9052-9058, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-36974427

RESUMO

Understanding ion transport in solid materials is crucial in the design of electrochemical devices. Of particular interest in recent years is the study of ion transport across 2-dimensional, atomically thin crystals. In this contribution, we describe the use of a host-guest hybrid redox material based on polyoxometalates (POMs) encapsulated within the internal cavities of single-walled carbon nanotubes (SWNTs) as a model system for exploring ion transport across atomically thin structures. The nanotube sidewall creates a barrier between the redox-active molecules and bulk electrolytes, which can be probed by addressing the redox states of the POMs electrochemically. The electrochemical properties of the {POM}@SWNT system are strongly linked to the nature of the cation in the supporting electrolyte. While acidic electrolytes facilitate rapid, exhaustive, reversible electron transfer and stability during redox cycling, alkaline-salt electrolytes significantly limit redox switching of the encapsulated species. By "plugging" the {POM}@SWNT material with C60-fullerenes, we demonstrate that the primary mode of charge balancing is proton transport through the graphenic lattice of the SWNT sidewalls. Kinetic analysis reveals little kinetic isotope effect on the standard heterogeneous electron transfer rate constant, suggesting that ion transport through the sidewalls is not rate-limiting in our system. The unique capacity of protons and deuterons to travel through graphenic layers unlocks the redox chemistry of nanoconfined redox materials, with significant implications for the use of carbon-coated materials in applications ranging from electrocatalysis to energy storage and beyond.

3.
Phys Chem Chem Phys ; 25(32): 21509-21520, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37540208

RESUMO

A protic ionic liquid (PIL), N,N-diethyl-N-methyl ammonium trifluoromethane sulfonate, [dema][TfO] was synthesized and confirmed using 1H-NMR and ion chromatography (IC). The surface electrocatalysis of ethanol (EtOH) and dimethyl ether (DME) was investigated on a polycrystalline Pt electrode in a PIL using a cyclic voltammetry technique. The voltammetry response shows that surface Pt-oxides/hydroxides (PtOH/PtO) are formed due to the oxidation of trace water (240 ppm determined by coulometric Karl-Fischer (FT) titration) in [dema][TfO] which plays a pivotal role during the electrocatalytic oxidation of EtOH and DME in the PIL. Oxidation of EtOH and DME coincides with coverage of the Pt surface by the adsorbed oxide species that helps to activate both processes by oxidizing the adsorbed poisoning CO and CO-like intermediate species via a 'bifunctional' reaction mechanism. The influence of temperature was investigated to obtain quantitative and qualitative information on the kinetics of EtOH oxidation. Higher activation energies are measured for EtOH oxidation in [dema][TfO] than in aqueous electrolytes due to the low water content and high viscosity of the PIL. This study gave a basic insight into the mechanism of EtOH and DME oxidation reactions, and the Pt-electrode poisoning species formation mechanism in the neoteric electrolyte medium is electrochemically investigated and reported.

4.
J Oncol Pharm Pract ; 29(7): 1776-1780, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37332111

RESUMO

INTRODUCTION: Medication reconciliation as part of a Comprehensive Geriatric Assessment by a specialist pharmacist is a process that has been shown to be beneficial in terms of medication adherence in patients taking oral anticancer medication and potentially cost-effective in cancer patients. Medication review guidelines in older adults with cancer suggest using polypharmacy (≥ 5 medications) as an indication for medication review in older adults with cancer. CASE REPORT: We present a case where a medication review as part of a Comprehensive Geriatric Assessment in the absence of polypharmacy resulted in two pharmacist interventions when standard care resulted in no intervention. A 71-year-old male prescribed capecitabine for rectal cancer had a medication reconciliation done as standard care before starting an oral anticancer medication. He then proceeded to get a medication review as part of a Comprehensive Geriatric Assessment and was deemed to have a potentially excessive anticholinergic burden and underprescribed gastro protection. This case is interesting as it occurred in a patient who would not have met the current inclusion criteria for a medication review as part of a Comprehensive Geriatric Assessment. MANAGEMENT AND OUTCOME: As a result of the Comprehensive Geriatric Assessment, a letter was written to the patient's general practitioner, recommending a change to anti-depressant therapy to optimise anticholinergic burden, as well as introducing a proton-pump inhibitor upon completion of the Capecitabine protocol concurrent with radiotherapy, to confer gastro-protection against the antidepressant medication, as per the START criteria. Upon discharge from medical oncology, neither of the changes had been adopted by the patient's general practitioner. This highlights one of the challenges facing clinical pharmacists in an outpatient setting, where evidence-based recommendations are not always implemented as care transitions from tertiary to primary care. CONCLUSION: Comprehensive Geriatric Assessment is a process that identifies potential issues in older adults with cancer that aren't identified with standard medication review. This is also evident for medication reviews as part of a Comprehensive Geriatric Assessment, and where resources allow, and recommendations are likely to be accepted, it should be offered to all older adults with cancer. Pharmacists are still faced with challenges in implementing recommendations from medication reviews, particularly in healthcare systems where pharmacist prescribing has yet to be introduced.


Assuntos
Prescrição Inadequada , Neoplasias Retais , Masculino , Idoso , Humanos , Prescrição Inadequada/prevenção & controle , Polimedicação , Avaliação Geriátrica/métodos , Capecitabina/uso terapêutico , Farmacêuticos , Antagonistas Colinérgicos
5.
J Neurophysiol ; 127(1): 86-98, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34788174

RESUMO

The transcriptional coactivator, PGC-1α (peroxisome proliferator-activated receptor γ coactivator 1α), plays a key role in coordinating energy requirement within cells. Its importance is reflected in the growing number of psychiatric and neurological conditions that have been associated with reduced PGC-1α levels. In cortical networks, PGC-1α is required for the induction of parvalbumin (PV) expression in interneurons, and PGC-1α deficiency affects synchronous GABAergic release. It is unknown, however, how this affects cortical excitability. We show here that knocking down PGC-1α specifically in the PV-expressing cells (PGC-1αPV-/-) blocks the activity-dependent regulation of the synaptic proteins, SYT2 and CPLX1. More surprisingly, this cell class-specific knockout of PGC-1α appears to have a novel antiepileptic effect, as assayed in brain slices bathed in 0 Mg2+ media. The rate of occurrence of preictal discharges developed approximately equivalently in wild-type and PGC-1αPV-/- brain slices, but the intensity of these discharges was lower in PGC-1αPV-/- slices, as evident from the reduced power in the γ range and reduced firing rates in both PV interneurons and pyramidal cells during these discharges. Reflecting this reduced intensity in the preictal discharges, the PGC-1αPV-/- brain slices experienced many more discharges before transitioning into a seizure-like event. Consequently, there was a large increase in the latency to the first seizure-like event in brain slices lacking PGC-1α in PV interneurons. We conclude that knocking down PGC-1α limits the range of PV interneuron firing and this slows the pathophysiological escalation during ictogenesis.NEW & NOTEWORTHY Parvalbumin expressing interneurons are considered to play an important role in regulating cortical activity. We were surprised, therefore, to find that knocking down the transcriptional coactivator, PGC-1α, specifically in this class of interneurons appears to slow ictogenesis. This anti-ictogenic effect is associated with reduced activity in preictal discharges, but with a far longer period of these discharges before the first seizure-like events finally start. Thus, PGC-1α knockdown may promote schizophrenia while reducing epileptic tendencies.


Assuntos
Excitabilidade Cortical/fisiologia , Interneurônios/metabolismo , Neocórtex/metabolismo , Parvalbuminas/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Células Piramidais/metabolismo , Convulsões/metabolismo , Convulsões/fisiopatologia , Animais , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/deficiência
6.
Chem Soc Rev ; 50(10): 5863-5883, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34027958

RESUMO

This Tutorial Review describes how the development of dissolved redox-active molecules is beginning to unlock the potential of three of the most promising 'next-generation' battery technologies - lithium-air, lithium-sulfur and redox-flow batteries. Redox-active molecules act as mediators in lithium-air and lithium-sulfur batteries, shuttling charge between electrodes and substrate systems and improving cell performance. In contrast, they act as the charge-storing components in flow batteries. However, in each case the performance of the molecular species is strongly linked to their solubility, electrochemical and chemical stability, and redox potentials. Herein we describe key examples of the use of redox-active molecules in each of these battery technologies and discuss the challenges and opportunities presented by the development and use of redox-active molecules in these applications. We conclude by issuing a "call to arms" to our colleagues within the wider chemical community, whose synthetic, computational, and analytical skills can potentially make invaluable contributions to the development of next-generation batteries and help to unlock of world of potential energy-storage applications.

7.
Chem Soc Rev ; 50(19): 10895-10916, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34396376

RESUMO

Confinement of molecules within nanocontainers can be a powerful tool for controlling the states of guest-molecules, tuning properties of host-nanocontainers and triggering the emergence of synergistic properties within the host-guest systems. Among nanocontainers, single-walled carbon nanotubes - atomically thin cylinders of carbon, with typical diameters below 2 nm and lengths reaching macroscopic dimensions - are ideal hosts for a variety of materials, including inorganic crystals, and organic, inorganic and organometallic molecules. The extremely high aspect ratio of carbon nanotubes is complemented by their functional properties, such as exceptionally high electrical conductivity and thermal, chemical and electrochemical stability, making carbon nanotubes ideal connectors between guest-molecules and macroscopic electrodes. The idea of harnessing nanotubes both as nanocontainers and nanoelectrodes has led to the incorporation of redox-active species entrapped within nanotube cavities where the host-nanotubes may serve as conduits of electrons to/from the guest-molecules, whilst restricting the molecular positions, orientations, and local environment around the redox centres. This review gives a contemporary overview of the status of molecular redox chemistry within ultra-narrow carbon nanotubes (nanotubes with diameters approaching molecular dimensions) highlighting the opportunities, pitfalls, and gaps in understanding of electrochemistry in confinement, including the role of nanotube diameter, size and shape of guest-molecules, type of electrolyte, solvent and other experimental conditions.

8.
Angew Chem Int Ed Engl ; 61(8): e202115619, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-34919306

RESUMO

We describe the preparation of hybrid redox materials based on polyoxomolybdates encapsulated within single-walled carbon nanotubes (SWNTs). Polyoxomolybdates readily oxidize SWNTs under ambient conditions in solution, and here we study their charge-transfer interactions with SWNTs to provide detailed mechanistic insights into the redox-driven encapsulation of these and similar nanoclusters. We are able to correlate the relative redox potentials of the encapsulated clusters with the level of SWNT oxidation in the resultant hybrid materials and use this to show that precise redox tuning is a necessary requirement for successful encapsulation. The host-guest redox materials described here exhibit exceptional electrochemical stability, retaining up to 86 % of their charge capacity over 1000 oxidation/reduction cycles, despite the typical lability and solution-phase electrochemical instability of the polyoxomolybdates we have explored. Our findings illustrate the broad applicability of the redox-driven encapsulation approach to the design and fabrication of tunable, highly conductive, ultra-stable nanoconfined energy materials.

9.
J Nutr ; 151(9): 2522-2532, 2021 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-34132337

RESUMO

BACKGROUND: In humans, vitamin B-12 (cobalamin) transport involves 3 paralogous proteins: transcobalamin, haptocorrin, and intrinsic factor. Zebrafish (Danio rerio) express 3 genes that encode proteins homologous to known B-12 carrier proteins: tcn2 (a transcobalamin ortholog) and 2 atypical ß-domain-only homologs, tcnba and tcnbb. OBJECTIVES: Given the orthologous relation between zebrafish Tcn2 and human transcobalamin, we hypothesized that zebrafish carrying null mutations of tcn2 would exhibit phenotypes consistent with vitamin B-12 deficiency. METHODS: First-generation and second-generation tcn2-/- zebrafish were characterized using phenotypic assessments, metabolic analyses, viability studies, and transcriptomics. RESULTS: Homozygous tcn2-/- fish produced from a heterozygous cross are viable and fertile but exhibit reduced growth, which persists into adulthood. When first-generation female tcn2-/- fish are bred, their offspring exhibit gross developmental and metabolic defects. These phenotypes are observed in all offspring from a tcn2-/- female regardless of the genotype of the male mating partner, suggesting a maternal effect, and can be rescued with vitamin B-12 supplementation. Transcriptome analyses indicate that offspring from a tcn2-/- female exhibit expression profiles distinct from those of offspring from a tcn2+/+ female, which demonstrate dysregulation of visual perception, fatty acid metabolism, and neurotransmitter signaling pathways. CONCLUSIONS: Our findings suggest that the deposition of vitamin B-12 in the yolk by tcn2-/- females may be insufficient to support the early development of their offspring. These data present a compelling model to study the effects of vitamin B-12 deficiency on early development, with a particular emphasis on transgenerational effects and gene-environment interactions.


Assuntos
Herança Materna , Peixe-Zebra , Adulto , Animais , Feminino , Humanos , Masculino , Transcobalaminas/genética , Vitamina B 12 , Vitaminas , Peixe-Zebra/genética
10.
Angew Chem Int Ed Engl ; 59(34): 14331-14335, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32432351

RESUMO

We report the design and preparation of multifunctional hybrid nanomaterials through the stabilization of gold nanoparticles with thiol-functionalised hybrid organic-inorganic polyoxometalates (POMs). The covalent attachment of the hybrid POM forms new nanocomposites that are stable at temperatures and pH values which destroy analogous electrostatically functionalised nanocomposites. Photoelectrochemical analysis revealed the unique photochemical and redox properties of these systems.

11.
J Physiol ; 595(11): 3549-3572, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28295330

RESUMO

KEY POINTS: The nucleus reuniens (Re), a nucleus of the midline thalamus, is part of a cognitive network including the hippocampus and the medial prefrontal cortex. To date, very few studies have examined the electrophysiological properties of Re neurons at a cellular level. The majority of Re neurons exhibit spontaneous action potential firing at rest. This is independent of classical amino-acid mediated synaptic transmission. When driven by various forms of depolarizing current stimulus, Re neurons display considerable diversity in their firing patterns. As a result of the presence of a low threshold Ca2+ channel, spike output functions are strongly modulated by the prestimulus membrane potential. Finally, we describe a novel form of activity-dependant intrinsic plasticity that eliminates the high-frequency burst firing present in many Re neurons. These results provide a comprehensive summary of the intrinsic electrophysiological properties of Re neurons allowing us to better consider the role of the Re in cognitive processes. ABSTRACT: The nucleus reuniens (Re) is the largest of the midline thalamic nuclei. We have performed a detailed neurophysiological characterization of neurons in the rostral Re of brain slices prepared from adult male mice. At resting potential (-63.7 ± 0.6 mV), ∼90% of Re neurons fired action potentials, typically continuously at ∼8 Hz. Although Re neurons experience a significant spontaneous barrage of fast, amino-acid-mediate synaptic transmission, this was not predominantly responsible for spontaneous spiking because firing persisted in the presence of glutamate and GABA receptor antagonists. With resting potential preset to -80 mV, -20 pA current injections revealed a mean input resistance of 615 MΩ and a mean time constant of 38 ms. Following cessation of this stimulus, a significant rebound potential was seen that was sometimes sufficiently large to trigger a short burst of very high frequency (100-300 Hz) firing. In most cells, short (2 ms), strong (2 nA) current injections elicited a single spike followed by a large afterdepolarizing potential which, when suprathreshold, generated high-frequency spiking. Similarly, in the majority of cells preset at -80 mV, 500 ms depolarizing current injections to cells led to a brief initial burst of very high-frequency firing, although this was lost when cells were preset at -72 mV. Biophysical and pharmacological experiments indicate a prominent role for T-type Ca2+ channels in the high-frequency bursting of Re neurons. Finally, we describe a novel form of activity-dependent intrinsic plasticity that persistently eliminates the burst firing potential of Re neurons.


Assuntos
Potenciais de Ação , Núcleos da Linha Média do Tálamo/fisiologia , Neurônios/fisiologia , Animais , Canais de Cálcio Tipo T/metabolismo , Ácido Glutâmico/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Núcleos da Linha Média do Tálamo/citologia , Neurônios/metabolismo , Receptores de GABA/metabolismo
12.
Chemistry ; 23(69): 17598-17604, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-28945301

RESUMO

The generation of sulfonyl radicals from sulfonyl azides using visible light and a photoactive iridium complex in THF is described. This process was used to promote sulfonylative and azidosulfonylative cyclizations of enynes to give several classes of highly functionalized heterocycles. The use of THF as the solvent is critical for successful reactions. The proposed mechanism of radical initiation involves the photosensitized formation of a triplet sulfonyl nitrene, which abstracts a hydrogen atom from THF to give a tetrahydrofuran-2-yl radical, which then reacts with the sulfonyl azide to generate the sulfonyl radical.

13.
Langmuir ; 33(34): 8436-8446, 2017 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-28780867

RESUMO

Protic ionic liquids (PILs) are ionic liquids that are formed by transferring protons from Brønsted acids to Brønsted bases. While they nominally consist entirely of ions, PILs can often behave as though they contain a significant amount of neutral species (either molecules or ion clusters), and there is currently a lot of interest in determining the degree of "ionicity" of PILs. In this contribution, we describe a simple electroanalytical method for detecting and quantifying residual excess acids in a series of ammonium-based PILs (diethylmethylammonium triflate [dema][TfO], dimethylethylammonium triflate [dmea][TfO], triethylammonium trifluoroacetate [tea][TfAc], and dimethylbutylammonium triflate [dmba][TfO]). Ultra-microelectrode voltammetry reveals that some of the accepted methods for synthesizing PILs can readily result in the formation of nonstoichiometric PILs containing up to 230 mM excess acid. In addition, vacuum purification of PILs is of limited use in cases where nonstoichiometric PILs are formed. Although excess bases can be readily removed from PILs under ambient conditions, excess acids cannot be removed, even under high vacuum. The effects of excess acid on the electrocatalytic oxygen reduction reaction (ORR) in PILs have been studied, and the onset potential of the ORR in [dema][TfO] increases by 0.8 V upon addition of acid to PIL. On the basis of the results of our analyses, we provide some recommendations for the synthesis of highly ionic PILs.

14.
Faraday Discuss ; 190: 127-45, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27228384

RESUMO

Environmental concerns have brought attention to the requirement for more efficient and renewable processes for chemicals production. Lignin is the second most abundant natural polymer, and might serve as a sustainable resource for manufacturing fuels and aromatic derivatives for the chemicals industry after being depolymerised. In this work, the mediator 2,2'-azino-bis(3-ethylbenthiazoline-6-sulfonic acid) diammonium salt (ABTS), commonly used with enzyme degradation systems, has been evaluated by means of cyclic voltammetry (CV) for enhancing the oxidation of the non-phenolic lignin model compound veratryl alcohol and three types of lignin (organosolv, Kraft and lignosulfonate) in the ionic liquid 1-ethyl-3-methylimidazolium ethyl sulfate, ([C2mim][C2SO4]). The presence of either veratryl alcohol or organosolv lignin increased the second oxidation peak of ABTS under select conditions, indicating the ABTS-mediated oxidation of these molecules at high potentials in [C2mim][C2SO4]. Furthermore, CV was applied as a quick and efficient way to explore the impact of water in the ABTS-mediated oxidation of both organosolv and lignosulfonate lignin. Higher catalytic efficiencies of ABTS were observed for lignosulfonate solutions either in sodium acetate buffer or when [C2mim][C2SO4] (15 v/v%) was present in the buffer solution, whilst there was no change found in the catalytic efficiency of ABTS in [C2mim][C2SO4]-lignosulfonate mixtures relative to ABTS alone. In contrast, organosolv showed an initial increase in oxidation, followed by a significant decrease on increasing the water content of a [C2mim][C2SO4] solution.


Assuntos
Biomassa , Líquidos Iônicos/química , Lignina/química , Benzotiazóis/química , Álcoois Benzílicos/química , Soluções Tampão , Catálise , Eficiência , Eletroquímica , Transferência de Energia , Imidazóis , Indicadores e Reagentes , Oxirredução , Ácidos Sulfônicos/química , Viscosidade , Água/química
15.
J Geriatr Oncol ; 15(3): 101722, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38461641

RESUMO

INTRODUCTION: The increase in statin use, since their introduction, has been rapid and the broadening of indications has occurred seemingly without restriction. Once established on statin therapy, there is sparse research on discontinuation. Trials do not often address benefit in later life, or the impact of a life-limiting diagnosis. Data on primary prevention suggest that 100 patients need treatment for 2.5 years to prevent one major adverse cardiovascular event. Acknowledging this, we sought to determine the use of statins in a cohort of older adults with cancer, to highlight prevalence, and suggest a role for deprescribing. MATERIALS AND METHODS: Data were retrospectively collected from a prospectively maintained database of patients attending a single centre Geriatric Oncology clinic. Data collected included sex, age, cancer type and stage, systemic anti-cancer therapy (SACT) recommendation, comorbidities, non-SACT medications, and overall survival. For those receiving statin therapy, data were separated into primary prevention and stage IV cancer. RESULTS: In the group studied (n = 230), 135 (59%) were prescribed a statin, with 79 (58%) for primary prevention. Ninety-three (40%) had stage IV cancer. Of the 230 patients, 134 (58%) were recommended SACT. Within the primary prevention group, the median age was 79 years. Twenty-seven patients (34%) had stage III disease, while 36 (46%) had stage IV disease. Thirteen (16%) had diabetes mellitus. The median number of medications was seven (Interquartile range 5). Fifty patients (63%) were recommended SACT. In terms of survival, 31 (50%) were alive at one year, 18 (29%) alive at two years, and 14 (23%) alive beyond two and a half years. Within the stage IV disease group, 59 out of 93 (63%) were receiving statin therapy; 35 (59%) for primary prevention and seven (8%) for diabetes mellitus. Fifty-eight (63%) were recommended SACT. Twenty-four (29%) were alive at one year, 17 (21%) alive at two years, and 13 (16%) alive beyond two and a half years. DISCUSSION: Statin therapy is prevalent and continues into older age. Available data regarding statin therapy in older adults and survival seen in this study support deprescribing in primary prevention and life-limiting illness, such as stage IV cancer.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias , Humanos , Idoso , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Estudos Retrospectivos , Neoplasias/tratamento farmacológico , Neoplasias/diagnóstico , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/epidemiologia
16.
Res Social Adm Pharm ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38705819

RESUMO

BACKGROUND: Geriatric Oncology is a specialty where a multidisciplinary approach can address the unmet needs of older adults with cancer. Older adults are at increased risk of adverse drug events (ADE) due to age-related changes in pharmacokinetics and pharmacodynamics, increasing treatment complexity, and medication burden. OBJECTIVES: To review the literature to determine the incidence of unplanned hospitalisation due to ADE for all medications, both systemic anticancer therapy (SACT) and non-SACT medications. METHODS: A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. The search included the following databases: PubMed, CINAHL, and Embase. A manual search of Scopus was then performed. Study quality was assessed using the Cochrane Handbook for Systematic Reviews of Interventions, Mixed Methods Appraisal Tool (MMAT) and Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework. RESULTS: Overall, three studies were included. One observational study reported 19 % of unplanned hospital admissions due to ADE in patients aged ≥70 years with cancer. The first retrospective study reported 24 % of unplanned hospital admissions are due to ADE in patients aged ≥70 years with cancer, and the second retrospective study reported 26 % of patients with metastatic melanoma treated with immune checkpoint inhibitors had an unplanned hospital admission due to an ADE. CONCLUSION: There is a paucity of studies assessing unplanned hospitalisation due to ADE in older adults with cancer. Future studies are needed and should account for the reporting of potential ADE relative to supportive care, ancillary medications, and indeed chronic medications used to treat long-standing comorbidities.

17.
PNAS Nexus ; 3(4): pgae116, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38560530

RESUMO

One-carbon metabolism is a complex network of metabolic reactions that are essential for cellular function including DNA synthesis. Vitamin B12 and folate are micronutrients that are utilized in this pathway and their deficiency can result in the perturbation of one-carbon metabolism and subsequent perturbations in DNA replication and repair. This effect has been well characterized in nuclear DNA but to date, mitochondrial DNA (mtDNA) has not been investigated extensively. Mitochondrial variants have been associated with several inherited and age-related disease states; therefore, the study of factors that impact heteroplasmy are important for advancing our understanding of the mitochondrial genome's impact on human health. Heteroplasmy studies require robust and efficient mitochondrial DNA enrichment to carry out in-depth mtDNA sequencing. Many of the current methods for mtDNA enrichment can introduce biases and false-positive results. Here, we use a method that overcomes these limitations and have applied it to assess mitochondrial heteroplasmy in mouse models of altered one-carbon metabolism. Vitamin B12 deficiency was found to cause increased levels of mitochondrial DNA heteroplasmy across all tissues that were investigated. Folic acid supplementation also contributed to elevated mitochondrial DNA heteroplasmy across all mouse tissues investigated. Heteroplasmy analysis of human data from the Framingham Heart Study suggested a potential sex-specific effect of folate and vitamin B12 status on mitochondrial heteroplasmy. This is a novel relationship that may have broader consequences for our understanding of one-carbon metabolism, mitochondrial-related disease and the influence of nutrients on DNA mutation rates.

18.
Front Neurosci ; 18: 1287228, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495109

RESUMO

Introduction: Expression of light sensitive ion channels by selected neurons has been achieved by viral mediated transduction with gene constructs, but for this to have therapeutic uses, for instance in treating epilepsy, any adverse effects of viral infection on the cerebral cortex needs to be evaluated. Here, we assessed the impact of adeno-associated virus 8 (AAV8) carrying DNA code for a soma targeting light activated chloride channel/FusionRed (FR) construct under the CKIIa promoter. Methods: Viral constructs were harvested from transfected HEK293 cells in vitro and purified. To test functionality of the opsin, cultured rodent neurons were transduced and the light response of transduced neurons was assayed using whole-cell patch-clamp recordings. In vivo expression was confirmed by immunofluorescence for FR. Unilateral intracranial injections of the viral construct were made into the mouse neocortex and non-invasive fluorescence imaging of FR expression made over 1-4 weeks post-injection using an IVIS Spectrum system. Sections were also prepared from injected mouse cortex for immunofluorescence staining of FR, alongside glial and neuronal marker proteins. Results: In vitro, cortical neurons were successfully transduced, showing appropriate physiological responses to light stimulation. Following injections in vivo, transduction was progressively established around a focal injection site over a 4-week period with spread of transduction proportional to the concentration of virus introduced. Elevated GFAP immunoreactivity, a marker for reactive astrocytes, was detected near injection sites associated with, and proportional to, local FR expression. Similarly, we observed reactive microglia around FR expressing cells. However, we found that the numbers of NeuN+ neurons were conserved close to the injection site, indicating that there was little or no neuronal loss. In control mice, injected with saline only, astrocytosis and microgliosis was limited to the immediate vicinity of the injection site. Injections of opsin negative viral constructs resulted in comparable levels of astrocytic reaction as seen with opsin positive constructs. Discussion: We conclude that introduction of an AAV8 vector transducing expression of a transgene under a neuron specific promotor evokes a mild inflammatory reaction in cortical tissue without causing extensive short-term neuronal loss. The expression of an opsin in addition to a fluorescent protein does not significantly increase neuroinflammation.

19.
J Geriatr Oncol ; 15(5): 101760, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38556399

RESUMO

Both randomized controlled trials (RCTs) and retrospective studies have shown that a comprehensive geriatric assessment (CGA) prior to a patient commencing systemic anti-cancer therapy (SACT) results in improved quality of life outcomes and is associated with a decreased risk of grade 3-5 toxicity; however, data are lacking in relation to adverse drug events (ADE) associated with supportive care medications. Supportive care medications are prescribed as prophylactic agents in a SACT regimen, for management of treatment related toxicity and for symptoms caused by the disease itself. While necessary, the commencement of SACT and supportive medications may cause, or exacerbate, a significant drug burden in older patients, some of whom may have existing comorbidities. For many medications, older adults are underrepresented in pharmacokinetic and pharmacodynamic modelling studies. In this article we will review ageing-related changes in pharmacokinetics and pharmacodynamics, as well as how these changes may impact supportive care medications. Additional considerations for prescribing these medications in older adults with cancer, such as polypharmacy, potentially inappropriate medications, drug-drug interactions, and anticholinergic burden, as well as ageing-related considerations and recommendations for supportive care medications commonly used in older adults with cancer are also reviewed.


Assuntos
Antineoplásicos , Interações Medicamentosas , Avaliação Geriátrica , Neoplasias , Polimedicação , Humanos , Neoplasias/tratamento farmacológico , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Envelhecimento , Qualidade de Vida , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Cuidados Paliativos/métodos
20.
Adv Mater ; 36(13): e2309998, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38108580

RESUMO

While significant advancements in power conversion efficiencies (PCEs) of α-FAPbI3perovskite solar cells (PSCs) have been made, attaining controllable perovskite crystallization is still a considerable hurdle. This challenge stems from the initial formation of δ-FAPbI3, a more energetically stable phase than the desired black α-phase, during film deposition. This disrupts the heterogeneous nucleation of α-FAPbI3, causing the formation of mixed phases and defects. To this end, polarity engineering using molecular additives, specifically ((methyl-sulfonyl)phenyl)ethylamines (MSPEs) are introduced. The findings reveal that the interaction of PbI2-MSPEs-FAI intermediates is enhanced with the increased polarity of MSPEs, which in turn expedites the nucleation of α-FAPbI3. This leads to the development of high-quality α-FAPbI3 films, characterized by vertical crystal orientation and reduced residual stresses. Additionally, the increased dipole moment of MSPE at perovskite grain boundaries attenuates Coulomb attractions among charged defects and screens carrier capture process, thereby diminishing non-radiative recombination. Utilizing these mechanisms, PSCs treated with highly polar 2-(4-MSPE) achieve an impressive PCE of 25.2% in small-area devices and 20.5% in large-area perovskite solar modules (PSMs) with an active area of 70 cm2. These results demonstrate the effectiveness of this strategy in achieving controllable crystallization of α-FAPbI3, paving the way for scalable-production of high-efficiency PSMs.

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