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1.
J Chem Phys ; 161(7)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39145566

RESUMO

Gas-phase molecules are a promising platform to elucidate the mechanisms of action and scope of polaritons for optical control of chemistry. Polaritons arise from the strong coupling of a dipole-allowed molecular transition with the photonic mode of an optical cavity. There is mounting evidence of modified reactivity under polaritonic conditions; however, the complex condensed-phase environment of most experimental demonstrations impedes mechanistic understanding of this phenomenon. While the gas phase was the playground of early efforts in atomic cavity quantum electrodynamics, we have only recently demonstrated the formation of molecular polaritons under these conditions. Studying the reactivity of isolated gas-phase molecules under strong coupling would eliminate solvent interactions and enable quantum state resolution of reaction progress. In this Perspective, we contextualize recent gas-phase efforts in the field of polariton chemistry and offer a practical guide for experimental design moving forward.

2.
Res Involv Engagem ; 10(1): 73, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010175

RESUMO

BACKGROUND: Engagement and partnership with consumers and communities throughout research processes produces high quality research meeting community needs and promoting translation of research into improved policy and practice. Partnership is critical in research involving Aboriginal and/or Torres Strait Islander people (First Nations Peoples) to ensure cultural safety. We present lessons from the design, implementation and progress of the National Health and Medical Research Council funded INtravenous iron polymaltose for First Nations Australian patients with high FERRitin levels on hemodialysis (INFERR) clinical trial. MAIN BODY: The trial was designed to understand the benefits and harms of iron therapy in First Nations Australians on haemodialysis with anaemia and hyperferritinaemia. The lack of evidence for treatment was discussed with patients who were potential participants. A key element ensuring safe conduct of the INFERR trial was the establishment of the Indigenous Reference Groups (IRGs) comprising of dialysis patients based in the Top End of Australia and Central Australia. Two IRGs were needed based on advice from First Nations communities and researchers/academics on the project regarding local cultural differences and approaches to trial conduct. The IRGs underpin culturally safe trial conduct by providing input into study materials and translating study findings into effective messages and policies for First Nations dialysis patients. Throughout the trial conduct, the IRGs' role has developed to provide key mechanisms for advice and guidance regarding research conduct both in this study and more broadly. Support provided to the IRGs by trial First Nations Research Officers and independent First Nations researchers/academics who simplify research concepts is critical. The IRGs have developed feedback documents and processes to participants, stakeholders, and the renal units. They guarantee culturally safe advice for embedding findings from the trial into clinical practice guidelines ensuring evidence-based approaches in managing anaemia in haemodialysis patients with hyperferritinaemia. CONCLUSION: Active consumer and community partnership is critical in research conduct to ensure research impact. Strong partnership with consumers in the INFERR clinical trial has demonstrated that First Nations Consumers will engage in research they understand, that addresses health priorities for them and where they feel respected, listened to, and empowered to achieve change.


In this paper, we present the importance of actively involving consumers in the planning, implementation and conduct of research using the example of a clinical trial among Aboriginal and/or Torres Strait Australians (First Nations Australians) who have kidney disease and are currently receiving haemodialysis. The study assesses how safe and effective it is for people on dialysis to receive iron given through the vein during dialysis when they have anaemia and high levels of a blood test called ferritin, a test used routinely to measure iron levels. Two consumer reference groups of First Nations patients on dialysis, one based in the Top End of Australia and the other based in Central Australia, are supported by First Nations Research Officers and Research Academics to make sure that the research is performed in a way that involves, respects and values First Nations participation, culture, and knowledge. Active consumer and community partnership in this study has supported robust research governance processes which we believe are crucial for knowledge translation to have a positive impact for patients.

3.
J Chem Phys ; 159(16)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37877486

RESUMO

Cavity coupling of gas-phase molecules will enable studies of benchmark chemical processes under strong light-matter interactions with a high level of experimental control and no solvent effects. We recently demonstrated the formation of gas-phase molecular polaritons by strongly coupling bright ν3, J = 3 → 4 rovibrational transitions of methane (CH4) to a Fabry-Pérot optical cavity mode inside a cryogenic buffer gas cell. Here, we further explore the flexible capabilities of this infrastructure. We show that we can greatly increase the collective coupling strength of the molecular ensemble to the cavity by increasing the intracavity CH4 number density. In doing so, we can tune from the single-mode coupling regime to a multimode coupling regime in which many nested polaritonic states arise as the Rabi splitting approaches the cavity mode spacing. We explore polariton formation for cavity geometries of varying length, finesse, and mirror radius of curvature. We also report a proof-of-principle demonstration of rovibrational gas-phase polariton formation at room temperature. This experimental flexibility affords a great degree of control over the properties of molecular polaritons and opens up a wider range of simple molecular processes to future interrogation under strong cavity-coupling. We anticipate that ongoing work in gas-phase polaritonics will facilitate convergence between experimental results and theoretical models of cavity-altered chemistry and physics.

4.
J Am Chem Soc ; 145(10): 5982-5987, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36867733

RESUMO

Polaritonic states arise when a bright optical transition of a molecular ensemble is resonantly matched to an optical cavity mode frequency. Here, we lay the groundwork to study the behavior of polaritons in clean, isolated systems by establishing a new platform for vibrational strong coupling in gas-phase molecules. We access the strong coupling regime in an intracavity cryogenic buffer gas cell optimized for the preparation of simultaneously cold and dense ensembles and report a proof-of-principle demonstration in gas-phase methane. We strongly cavity-couple individual rovibrational transitions and probe a range of coupling strengths and detunings. We reproduce our findings with classical cavity transmission simulations in the presence of strong intracavity absorbers. This infrastructure will provide a new testbed for benchmark studies of cavity-altered chemistry.

5.
PLoS Pathog ; 18(3): e1010337, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35255101

RESUMO

HLA-A*11:01 is one of the most prevalent human leukocyte antigens (HLAs), especially in East Asian and Oceanian populations. It is also highly expressed in Indigenous people who are at high risk of severe influenza disease. As CD8+ T cells can provide broadly cross-reactive immunity to distinct influenza strains and subtypes, including influenza A, B and C viruses, understanding CD8+ T cell immunity to influenza viruses across prominent HLA types is needed to rationally design a universal influenza vaccine and generate protective immunity especially for high-risk populations. As only a handful of HLA-A*11:01-restricted CD8+ T cell epitopes have been described for influenza A viruses (IAVs) and epitopes for influenza B viruses (IBVs) were still unknown, we embarked on an epitope discovery study to define a CD8+ T cell landscape for HLA-A*11:01-expressing Indigenous and non-Indigenous Australian people. Using mass-spectrometry, we identified IAV- and IBV-derived peptides presented by HLA-A*11:01 during infection. 79 IAV and 57 IBV peptides were subsequently screened for immunogenicity in vitro with peripheral blood mononuclear cells from HLA-A*11:01-expressing Indigenous and non-Indigenous Australian donors. CD8+ T cell immunogenicity screening revealed two immunogenic IAV epitopes (A11/PB2320-331 and A11/PB2323-331) and the first HLA-A*11:01-restricted IBV epitopes (A11/M41-49, A11/NS1186-195 and A11/NP511-520). The immunogenic IAV- and IBV-derived peptides were >90% conserved among their respective influenza viruses. Identification of novel immunogenic HLA-A*11:01-restricted CD8+ T cell epitopes has implications for understanding how CD8+ T cell immunity is generated towards IAVs and IBVs. These findings can inform the development of rationally designed, broadly cross-reactive influenza vaccines to ensure protection from severe influenza disease in HLA-A*11:01-expressing individuals.


Assuntos
Vírus da Influenza A , Vacinas contra Influenza , Influenza Humana , Austrália , Linfócitos T CD8-Positivos , Epitopos de Linfócito T , Antígenos HLA-A , Humanos , Povos Indígenas , Vírus da Influenza B , Leucócitos Mononucleares , Peptídeos
6.
Trials ; 22(1): 868, 2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34857020

RESUMO

BACKGROUND: The effectiveness of erythropoiesis-stimulating agents, which are the main stay of managing anaemia of chronic kidney disease (CKD), is largely dependent on adequate body iron stores. The iron stores are determined by the levels of serum ferritin concentration and transferrin saturation. These two surrogate markers of iron stores are used to guide iron replacement therapy. Most Aboriginal and/or Torres Islander Australians of the Northern Territory (herein respectfully referred to as First Nations Australians) with end-stage kidney disease have ferritin levels higher than current guideline recommendations for iron therapy. There is no clear evidence to guide safe and effective treatment with iron in these patients. We aim to assess the impact of intravenous iron treatment on all-cause death and hospitalisation with a principal diagnosis of all-cause infection in First Nations patients on haemodialysis with anaemia, high ferritin levels and low transferrin saturation METHODS: In a prospective open-label blinded endpoint randomised controlled trial, a total of 576 participants on maintenance haemodialysis with high ferritin (> 700 µg/L and ≤ 2000 µg/L) and low transferrin saturation (< 40%) from all the 7 renal units across the Northern Territory of Australia will be randomised 1:1 to receive intravenous iron polymaltose 400 mg once monthly (200 mg during 2 consecutive haemodialysis sessions) (Arm A) or no IV iron treatment (standard treatment) (Arm B). Rescue therapy will be administered when the ferritin levels fall below 700 µg/L or when clinically indicated. The primary outcome will be the differences between the two study arms in the risk of hospitalisation with all-cause infection or death. An economic analysis and several secondary and tertiary outcomes analyses will also be performed. DISCUSSION: The INFERR clinical trial will address significant uncertainty on the safety and efficacy of iron therapy in First Nations Australians with CKD with hyperferritinaemia and evidence of iron deficiency. This will hopefully lead to the development of evidence-based guidelines. It will also provide the opportunity to explore the causes of hyperferritinaemia in First Nations Australians from the Northern Territory. TRIAL REGISTRATION: This trial is registered with The Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12620000705987 . Registered 29 June 2020.


Assuntos
Povos Indígenas , Deficiências de Ferro , Austrália , Compostos Férricos , Ferritinas , Humanos , Ferro , Deficiências de Ferro/etnologia , Deficiências de Ferro/terapia , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Diálise Renal
7.
Behav Brain Res ; 359: 95-103, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30392852

RESUMO

Considering the current obesity epidemic is due in large part to an energy imbalance, it is crucial to explore biological mechanisms that mediate palatable high energy food intake and physical activity behavior levels. Previous research demonstrates a unique sex dependent influence of physical activity on diet preference, specifically changes in palatable high-fat diet intake. Therefore, factors of motivation may be underlying the differential effect of physical activity in male and female rats on their diet preference. The present study extends this hypothesis by assessing diet preference in male and female Wistar rats selectively bred for high (HVR) and low (LVR) levels of voluntary wheel running distances. HVR and LVR rats were housed under either sedentary (SED) or voluntary wheel running access (RUN) conditions for the duration of the study. Following a 1 week acclimation period to these conditions, standard chow was replaced with concurrent ad libitum access to a choice of 3 pelleted diets (high-fat, high-sucrose, and high-corn starch); all 3 were provided in the home cage. Body weight, running distance, and intake of each diet was measured daily. At the conclusion of the 4 week diet preference test, animals were sacrificed and ventral striatum tissue was collected for later analysis. Results demonstrated intake patterns of diets were uniquely influenced by physical activity dependent on both the sex and the selectively bred line of rat. In addition, reward related ventral striatal mRNA expression was also dependent on both the sex and the selectively bred line of rat. Overall, the pattern of both behavioral and mRNA results suggest that voluntary wheel running behavior differentially mediates palatable diet consumption in males and females. Considering the pervasive abundance of both physical inactivity, combined with over-consumption of energy dense palatable diets, it is vital to understand the nature of these behavioral interactions.


Assuntos
Preferências Alimentares , Atividade Motora , Corrida , Animais , Peso Corporal , Dieta Hiperlipídica , Sacarose Alimentar , Ingestão de Alimentos/fisiologia , Feminino , Preferências Alimentares/fisiologia , Masculino , Atividade Motora/fisiologia , RNA Mensageiro/metabolismo , Ratos Wistar , Recompensa , Corrida/fisiologia , Comportamento Sedentário , Seleção Artificial , Fatores Sexuais , Especificidade da Espécie , Amido , Estriado Ventral/metabolismo , Volição
8.
Breast J ; 15(1): 93-100, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19141135

RESUMO

Although two-thirds of invasive breast cancers and half of non-invasive breast cancers are amenable to lumpectomy, only about 70% of such patients choose breast conservation. Of that group, up to one-third do not follow-up with radiation therapy despite it being clinically indicated. The reasons include the patient's and surgeon's attitude toward breast conservation as well as the inconvenience and distance of a suitable radiation facility. The advent of shorter courses of radiation therapy may encourage more patients to seek adjuvant therapy. An increasingly popular and more convenient alternative to traditional whole-breast radiation therapy in patients with early-stage breast cancer is accelerated partial breast irradiation (APBI), for which the American Society of Breast Surgeons and the American Brachytherapy Society have promulgated guidelines for candidate selection. Although several methods are emerging, the most widely used brachytherapy technique utilizes the MammoSite single-catheter balloon brachytherapy device. In a best practices symposium convened in 2006, breast surgeons from academic and community practices with extensive experience in balloon brachytherapy developed general guidelines for integrating APBI into a breast surgical practice. Important considerations include patient age, histology, tumor location and size, and breast size. Thoughtful lumpectomy planning is essential to optimize balloon placement. Real-time sonographic guidance is essential as the surgeon should attend closely to volume excised and cavity shape. A cavity evaluation device can act as a place holder while patient suitability for APBI is considered. Many breast surgeons expert in this procedure insert the balloon catheter in the office either through a de novo skin entrance site removed from the lumpectomy incision or through the original incision. Optimally, insertion occurs within 2-3 weeks after lumpectomy. Close and continual communication with the radiation oncologist is essential to assure optimal outcomes. In this review, several key aspects of a successful APBI program from a surgeon's perspective as well as a consensus panel from a best practices symposium on the topic herein are highlighted.


Assuntos
Braquiterapia/métodos , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Mastectomia Segmentar , Papel do Médico , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade
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