1
|
Kirby A, Suchý M, Duan D, Bazett M, Kalyan S, Shuhendler AJ. Tracking the fate of bacteria-derived site-specific immunomodulators by positron emission tomography. Nucl Med Biol 2024; 132-133:108908. [PMID: 38599145 DOI: 10.1016/j.nucmedbio.2024.108908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 03/08/2024] [Accepted: 03/27/2024] [Indexed: 04/12/2024]
Abstract
INTRODUCTION Site-specific immunomodulators (SSIs) are a novel class of therapeutics made from inactivated bacterial species designed to regulate the innate immune system in targeted organs. QBECO is a gut-targeted SSI that is being advanced clinically to treat and/or prevent inflammatory bowel disease, cancer, and serious infections of the gastrointestinal (GI) tract and proximal organs, and QBKPN is a lung-targeted SSI that is in clinical development for the treatment and/or prevention of chronic inflammatory lung disease, lung cancers and respiratory tract infections. While these SSIs have demonstrated both safety and proof-of-concept in preclinical and clinical studies, detailed understanding of their trafficking and biodistribution is yet to be fully characterized. METHODS QBECO and QBKPN were radiolabeled with [89Zr] and injected subcutaneously into healthy mice. The mice underwent Positron Emission Tomography (PET) imaging every day for eight days to track biodistribution of the SSIs. Tissue from the site of injection was collected and immunohistologically probed for immune cell infiltration. RESULTS Differential biodistribution of the two SSIs was seen, adhering to their site-specific targeting. QBKPN appeared to migrate from the site of injection (abdomen) to the cervical lymph nodes which are nearer to the respiratory tract and lungs. QBECO remained in the abdominal region, with lymphatic trafficking to the inguinal lymph nodes, which are nearer to GI-proximal tissues/organs. Immune infiltration at the site of injection comprised of neutrophils for both SSIs, and macrophages for only QBKPN. CONCLUSION Radiolabeling of SSIs allows for longitudinal in vivo imaging of biodistribution and trafficking. PET imaging revealed differential biodistribution of the SSIs based on the organotropism of the bacteria from which the SSI is derived. Trafficking from the site of injection to the targeted site is in part mediated via the lymphatics and involves macrophages and neutrophils.
Collapse
|
2
|
Kirby A, Graf D, Suchý M, Calvert ND, Charlton TA, Ben RN, Addison CL, Shuhendler A. It's a Trap! Aldolase-Prescribed C 4 Deoxyradiofluorination Affords Intracellular Trapping and the Tracing of Fructose Metabolism by PET. J Nucl Med 2024; 65:475-480. [PMID: 38272705 DOI: 10.2967/jnumed.123.266905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/06/2023] [Accepted: 12/06/2023] [Indexed: 01/27/2024] Open
Abstract
Fructose metabolism has been implicated in various diseases, including metabolic disorders, neurodegenerative disorders, cardiac disorders, and cancer. However, the limited availability of a quantitative imaging radiotracer has hindered its exploration in pathology and diagnostic imaging. Methods: We adopted a molecular design strategy based on the catalytic mechanism of aldolase, a key enzyme in fructolysis. We successfully synthesized a radiodeoxyfluorinated fructose analog, [18F]4-fluoro-4-deoxyfructose ([18F]4-FDF), in high molar activity. Results: Through heavy isotope tracing by mass spectrometry, we demonstrated that C4-deoxyfluorination of fructose led to effective trapping as fluorodeoxysorbitol and fluorodeoxyfructose-1-phosphate in vitro, unlike C1- and C6-fluorinated analogs that resulted in fluorolactate accumulation. This observation was consistent in vivo, where [18F]6-fluoro-6-deoxyfructose displayed substantial bone uptake due to metabolic processing whereas [18F]4-FDF did not. Importantly, [18F]4-FDF exhibited low uptake in healthy brain and heart tissues, known for their high glycolytic activity and background levels of [18F]FDG uptake. [18F]4-FDF PET/CT allowed for sensitive mapping of neuro- and cardioinflammatory responses to systemic lipopolysaccharide administration. Conclusion: Our study highlights the significance of aldolase-guided C4 radiodeoxyfluorination of fructose in enabling effective radiotracer trapping, overcoming limitations of C1 and C6 radioanalogs toward a clinically viable tool for imaging fructolysis in highly glycolytic tissues.
Collapse
|
3
|
Kirby A, Shuhendler AJ. Small Animal Multisubject PET/CT Workflow. Methods Mol Biol 2024; 2729:185-193. [PMID: 38006497 DOI: 10.1007/978-1-0716-3499-8_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2023]
Abstract
Positron emission tomography (PET) is a highly sensitive molecular imaging technique that uses radioactive tracers to map molecular and metabolic processes in living animals. PET can be performed as a stand-alone modality but is often combined with CT to provide for objective anatomical localization of PET signals in a multimodality approach. In order to outline the general approach to evaluating four mice simultaneously by dynamic PET imaging, the use of the aldehyde-targeted radiotracer [18F]NA3BF3 in mouse models of hepatotoxicity will be described. Indeed the production of aldehydes is upregulated in a wide range of disease and injury, making them a suitable biomarker for PET imaging of numerous pathologies.
Collapse
|
4
|
Tan IZ, Mitchell A, McNair H, Dunlop A, Herbert T, Nartey J, Lawes R, O'Connell N, De-Colle C, Han K, Hahn E, Nelms B, Russell N, Kirby A. A Multicenter Study of Clinical to Planning Target Volume Margins for Adjuvant Partial Breast Irradiation Delivered on the 1.5T MR-Linear Accelerator. Int J Radiat Oncol Biol Phys 2023; 117:e725. [PMID: 37786112 DOI: 10.1016/j.ijrobp.2023.06.2237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Adjuvant partial breast irradiation (APBI) for early-stage breast cancer patients delivered on a conventional Linac commonly uses a clinical to planning target volume (CTV-PTV) margin of 10 mm. Published data suggest this margin could be reduced using an MR-guided workflow. This study quantifies the CTV to PTV margin for APBI delivered on the 1.5T MR-Linac (MRL) using an Adapt to Position (ATP) workflow. MATERIALS/METHODS All target contouring was done as per the IMPORT LOW trial and MRL Consortium guidelines. The CTV is the tumor bed defined by surgical clips including postsurgical changes. A single center cohort of ten patients was used to assess delineation error on ProKnow DS v1.28.0 by measuring CTV contour displacements on the CT planning scans (pCT) delineated by five breast radiation oncologists. All other error components were measured on treatment planning software on another single center cohort of ten patients. Target deformation error was measured as surgical clip displacements between the pCT and daily pre-treatment (pre-Tx) MRI scans. Intrafraction motion was determined by the CTV displacement between pre- and post-treatment MRIs (post-Tx) in available paired images from five patients. Matching error was estimated as the interobserver variation of three MRL radiographers registering the pCT with daily pre-Tx MRI. Technical delivery accuracy was estimated using the results from routine quality assurance measurements. Beam penumbral width (p) was estimated from the clinical treatment plans. The systematic (Σ) and random errors (σ) for each component were calculated in the left/right (X), superior/inferior (Y) and anterior/posterior (Z) directions. The contribution of these errors to the PTV margin, M was calculated using van Herk's formula with α and β being 2.50 and 1.64 respectively. RESULTS For APBI using an MRL ATP workflow, a CTV-PTV margin of 5.7 to 7.6 mm is required to achieve a 90% confidence of CTV coverage by the 95% isodose. Individual error components are in. Table 1 delineation error remains the largest component of error. CONCLUSION A minimum CTV-PTV margin of 6-8 mm is required for APBI using an MRL ATP workflow. Although smaller than margins used in conventional Linacs, the clinical benefits (in terms of fibrosis risk) of treating APBI patients on an MRL are likely to be modest. Further margin reductions may be possible using an "Adapt to Shape" workflow with daily online recontouring.
Collapse
|
5
|
Gates EWJ, Calvert ND, Cundy NJ, Brugnoli F, Navals P, Kirby A, Bianchi N, Adhikary G, Shuhendler AJ, Eckert RL, Keillor JW. Cell-Impermeable Inhibitors Confirm That Intracellular Human Transglutaminase 2 Is Responsible for the Transglutaminase-Associated Cancer Phenotype. Int J Mol Sci 2023; 24:12546. [PMID: 37628729 PMCID: PMC10454375 DOI: 10.3390/ijms241612546] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/24/2023] [Accepted: 07/31/2023] [Indexed: 08/27/2023] Open
Abstract
Transglutaminase 2 (TG2) is a multifunctional enzyme primarily responsible for crosslinking proteins. Ubiquitously expressed in humans, TG2 can act either as a transamidase by crosslinking two substrates through formation of an Nε(ɣ-glutaminyl)lysine bond or as an intracellular G-protein. These discrete roles are tightly regulated by both allosteric and environmental stimuli and are associated with dramatic changes in the conformation of the enzyme. The pleiotropic nature of TG2 and multi-faceted activities have resulted in TG2 being implicated in numerous disease pathologies including celiac disease, fibrosis, and cancer. Targeted TG2 therapies have not been selective for subcellular localization, such that currently no tools exist to selectively target extracellular over intracellular TG2. Herein, we have designed novel TG2-selective inhibitors that are not only highly potent and irreversible, but also cell impermeable, targeting only extracellular TG2. We have also further derivatized the scaffold to develop probes that are intrinsically fluorescent or bear an alkyne handle, which target both intra- and extracellular TG2, in order to facilitate cellular labelling and pull-down assays. The fluorescent probes were internalized and imaged in cellulo, and provide the first implicit experimental evidence that by comparison with their cell-impermeable analogues, it is specifically intracellular TG2, and presumably its G-protein activity, that contributes to transglutaminase-associated cancer progression.
Collapse
|
6
|
Calvert ND, Kirby A, Suchý M, Pallister P, Torrens AA, Burger D, Melkus G, Schieda N, Shuhendler AJ. Direct mapping of kidney function by DCE-MRI urography using a tetrazinanone organic radical contrast agent. Nat Commun 2023; 14:3965. [PMID: 37407664 DOI: 10.1038/s41467-023-39720-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 06/27/2023] [Indexed: 07/07/2023] Open
Abstract
Chronic kidney disease (CKD) and acute kidney injury (AKI) are ongoing global health burdens. Glomerular filtration rate (GFR) is the gold standard measure of kidney function, with clinical estimates providing a global assessment of kidney health without spatial information of kidney- or region-specific dysfunction. The addition of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) to the anatomical imaging already performed would yield a 'one-stop-shop' for renal assessment in cases of suspected AKI and CKD. Towards urography by DCE-MRI, we evaluated a class of nitrogen-centered organic radicals known as verdazyls, which are extremely stable even in highly reducing environments. A glucose-modified verdazyl, glucoverdazyl, provided contrast limited to kidney and bladder, affording functional kidney evaluation in mouse models of unilateral ureteral obstruction (UUO) and folic acid-induced nephropathy (FAN). Imaging outcomes correlated with histology and hematology assessing kidney dysfunction, and glucoverdazyl clearance rates were found to be a reliable surrogate measure of GFR.
Collapse
|
7
|
Béland-Millar A, Kirby A, Truong Y, Ouellette J, Yandiev S, Bouyakdan K, Pileggi C, Naz S, Yin M, Carrier M, Kotchetkov P, St-Pierre MK, Tremblay MÈ, Courchet J, Harper ME, Alquier T, Messier C, Shuhendler AJ, Lacoste B. 16p11.2 haploinsufficiency reduces mitochondrial biogenesis in brain endothelial cells and alters brain metabolism in adult mice. Cell Rep 2023; 42:112485. [PMID: 37149866 DOI: 10.1016/j.celrep.2023.112485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 02/20/2023] [Accepted: 04/22/2023] [Indexed: 05/09/2023] Open
Abstract
Neurovascular abnormalities in mouse models of 16p11.2 deletion autism syndrome are reminiscent of alterations reported in murine models of glucose transporter deficiency, including reduced brain angiogenesis and behavioral alterations. Yet, whether cerebrovascular alterations in 16p11.2df/+ mice affect brain metabolism is unknown. Here, we report that anesthetized 16p11.2df/+ mice display elevated brain glucose uptake, a phenomenon recapitulated in mice with endothelial-specific 16p11.2 haplodeficiency. Awake 16p11.2df/+ mice display attenuated relative fluctuations of extracellular brain glucose following systemic glucose administration. Targeted metabolomics on cerebral cortex extracts reveals enhanced metabolic responses to systemic glucose in 16p11.2df/+ mice that also display reduced mitochondria number in brain endothelial cells. This is not associated with changes in mitochondria fusion or fission proteins, but 16p11.2df/+ brain endothelial cells lack the splice variant NT-PGC-1α, suggesting defective mitochondrial biogenesis. We propose that altered brain metabolism in 16p11.2df/+ mice is compensatory to endothelial dysfunction, shedding light on previously unknown adaptative responses.
Collapse
|
8
|
De-Colle C, Kirby A, Russell N, Shaitelman S, Currey A, Donovan E, Hahn E, Han K, Anandadas C, Mahmood F, Lorenzen E, van den Bongard D, Groot Koerkamp M, Houweling A, Nachbar M, Thorwarth D, Zips D. Adaptive radiotherapy for breast cancer. Clin Transl Radiat Oncol 2023; 39:100564. [PMID: 36632056 PMCID: PMC9826896 DOI: 10.1016/j.ctro.2022.100564] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 12/07/2022] [Accepted: 12/14/2022] [Indexed: 12/24/2022] Open
Abstract
Research in the field of local and locoregional breast cancer radiotherapy aims to maintain excellent oncological outcomes while reducing treatment-related toxicity. Adaptive radiotherapy (ART) considers variations in target and organs at risk (OARs) anatomy occurring during the treatment course and integrates these in re-optimized treatment plans. Exploiting ART routinely in clinic may result in smaller target volumes and better OAR sparing, which may lead to reduction of acute as well as late toxicities. In this review MR-guided and CT-guided ART for breast cancer patients according to different clinical scenarios (neoadjuvant and adjuvant partial breast irradiation, whole breast, chest wall and regional nodal irradiation) are reviewed and their advantages as well as challenging aspects discussed.
Collapse
|
9
|
Holt F, Probert J, Liu Z, Duane F, Ntentas G, Darby S, Dodwell D, Coles C, Haviland J, Kirby A, Taylor C. Proton beam therapy for early breast cancer: a systematic review and quantitative synthesis of adverse clinical outcomes. Eur J Cancer 2022. [DOI: 10.1016/s0959-8049(22)01474-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
10
|
Webb K, Gothard L, Mohammed K, Kirby A, Locke I, Somaiah N. PD-0748 Local control and toxicity after hypofractionated accelerated palliative RT in breast cancer. Radiother Oncol 2022. [DOI: 10.1016/s0167-8140(22)02943-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
11
|
Westerhoff J, Daamen L, Christodouleas J, Blezer E, Choudhury A, Westley R, Erickson B, Fuller C, Hafeez S, van der Heide U, Intven M, Kirby A, Lalondrelle S, Minsky B, Mook S, Nowee M, Marijnen C, Orrling K, Sahgal A, Schultz C, Tersteeg R, Tree A, Tseng C, van der Voort van Zyp J, Verkooijen H, Hall W. OC-0419 Patterns of Care and Safety in 1800 patients treated on a high-field MR-Linac platform registry. Radiother Oncol 2022. [DOI: 10.1016/s0167-8140(22)02555-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
12
|
Wheatley D, Haviland J, Patel J, Sydenham M, Alhasso A, Chan C, Cleator S, Coles C, Donovan E, Kirby A, Kirwan C, Nabi Z, Sawyer E, Somaiah N, Syndikus I, Venables K, Yarnold J, Brunt A, Bliss J. OC-0101 First results of FAST-Forward phase 3 RCT nodal substudy: 3-year normal tissue effects. Radiother Oncol 2022. [DOI: 10.1016/s0167-8140(22)02477-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
13
|
Kirby A. SP-0710 How to get involved in ESTRO leadership. Radiother Oncol 2022. [DOI: 10.1016/s0167-8140(22)04031-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
14
|
Thompson PL, Hui J, Beilby J, Palmer LJ, Watts GF, West MJ, Kirby A, Marschner S, Simes RJ, Sullivan DR, White HD, Stewart R, Tonkin AM. Common genetic variants do not predict recurrent events in coronary heart disease patients. BMC Cardiovasc Disord 2022; 22:96. [PMID: 35264114 PMCID: PMC8908687 DOI: 10.1186/s12872-022-02520-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 02/07/2022] [Indexed: 11/15/2022] Open
Abstract
Background It is unclear whether genetic variants identified from single nucleotide polymorphisms (SNPs) strongly associated with coronary heart disease (CHD) in genome-wide association studies (GWAS), or a genetic risk score (GRS) derived from them, can help stratify risk of recurrent events in patients with CHD. Methods Study subjects were enrolled at the close-out of the LIPID randomised controlled trial of pravastatin vs placebo. Entry to the trial had required a history of acute coronary syndrome 3–36 months previously, and patients were in the trial for a mean of 36 months. Patients who consented to a blood sample were genotyped with a custom designed array chip with SNPs chosen from known CHD-associated loci identified in previous GWAS. We evaluated outcomes in these patients over the following 10 years. Results Over the 10-year follow-up of the cohort of 4932 patients, 1558 deaths, 898 cardiovascular deaths, 727 CHD deaths and 375 cancer deaths occurred. There were no significant associations between individual SNPs and outcomes before or after adjustment for confounding variables and for multiple testing. A previously validated 27 SNP GRS derived from SNPs with the strongest associations with CHD also did not show any independent association with recurrent major cardiovascular events. Conclusions Genetic variants based on individual single nucleotide polymorphisms strongly associated with coronary heart disease in genome wide association studies or an abbreviated genetic risk score derived from them did not help risk profiling in this well-characterised cohort with 10-year follow-up. Other approaches will be needed to incorporate genetic profiling into clinically relevant stratification of long-term risk of recurrent events in CHD patients. Supplementary Information The online version contains supplementary material available at 10.1186/s12872-022-02520-0.
Collapse
|
15
|
Kha R, Melov S, Alahakoon T, Kirby A, Choudhary P. Predicting Cardiac and Pregnancy Outcomes in Women With Adult Congenital Heart Disease: How Much Does Physiology Matter? Heart Lung Circ 2022. [DOI: 10.1016/j.hlc.2022.06.462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
|
16
|
Settatree S, Dunlop A, Mohajer J, Brand D, Mooney L, Ross G, Gulliford S, Harris E, Kirby A. What Can Proton Beam Therapy Achieve for Patients with Pectus Excavatum Requiring Left Breast, Axilla and Internal Mammary Nodal Radiotherapy? Clin Oncol (R Coll Radiol) 2021; 33:e570-e577. [PMID: 34226114 DOI: 10.1016/j.clon.2021.06.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 05/12/2021] [Accepted: 06/18/2021] [Indexed: 12/25/2022]
Abstract
AIMS Exposure of the heart to radiation increases the risk of ischaemic heart disease, proportionate to the mean heart dose (MHD). Radiotherapy techniques including proton beam therapy (PBT) can reduce MHD. The aims of this study were to quantify the MHD reduction achievable by PBT compared with volumetric modulated arc therapy in breath hold (VMAT-BH) in patients with pectus excavatum (PEx), to identify an anatomical metric from a computed tomography scan that might indicate which patients will achieve the greatest MHD reductions from PBT. MATERIALS AND METHODS Sixteen patients with PEx (Haller Index ≥2.7) were identified from radiotherapy planning computed tomography images. Left breast/chest wall, axilla (I-IV) and internal mammary node (IMN) volumes were delineated. VMAT and PBT plans were prepared, all satisfying target coverage constraints. Signed-rank comparisons of techniques were undertaken for the mean dose to the heart, ipsilateral lung and contralateral breast. Spearman's rho correlations were calculated for anatomical metrics against MHD reduction achieved by PBT. RESULTS The mean MHD for VMAT-BH plans was 4.1 Gy compared with 0.7 Gy for PBT plans. PBT reduced MHD by an average of 3.4 Gy (range 2.8-4.4 Gy) compared with VMAT-BH (P < 0.001). PBT significantly reduced the mean dose to the ipsilateral lung (4.7 Gy, P < 0.001) and contralateral breast (2.7 Gy, P < 0.001). The distance (mm) at the most inferomedial extent of IMN volume (IMN to heart distance) negatively correlated with MHD reduction achieved by PBT (Spearman's rho -0.88 (95% confidence interval -0.96 to -0.67, P < 0.001)). CONCLUSION For patients with PEx requiring left-sided breast and IMN radiotherapy, a clinically significant MHD reduction is achievable using PBT, compared with the optimal photon technique (VMAT-BH). This is a patient group in whom PBT could have the greatest benefit.
Collapse
|
17
|
Cheng H, Sebaa R, Malholtra N, Lacoste B, El Hankouri Z, Kirby A, Bennett NC, van Jaarsveld B, Hart DW, Tattersall GJ, Harper ME, Pamenter ME. Naked mole-rat brown fat thermogenesis is diminished during hypoxia through a rapid decrease in UCP1. Nat Commun 2021; 12:6801. [PMID: 34815412 PMCID: PMC8610999 DOI: 10.1038/s41467-021-27170-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 11/08/2021] [Indexed: 11/17/2022] Open
Abstract
Naked mole-rats are among the most hypoxia-tolerant mammals. During hypoxia, their body temperature (Tb) decreases via unknown mechanisms to conserve energy. In small mammals, non-shivering thermogenesis in brown adipose tissue (BAT) is critical to Tb regulation; therefore, we hypothesize that hypoxia decreases naked mole-rat BAT thermogenesis. To test this, we measure changes in Tb during normoxia and hypoxia (7% O2; 1-3 h). We report that interscapular thermogenesis is high in normoxia but ceases during hypoxia, and Tb decreases. Furthermore, in BAT from animals treated in hypoxia, UCP1 and mitochondrial complexes I-V protein expression rapidly decrease, while mitochondria undergo fission, and apoptosis and mitophagy are inhibited. Finally, UCP1 expression decreases in hypoxia in three other social African mole-rat species, but not a solitary species. These findings suggest that the ability to rapidly down-regulate thermogenesis to conserve oxygen in hypoxia may have evolved preferentially in social species.
Collapse
|
18
|
Brun EMSPT, Calvert ND, Suchý M, Kirby A, Melkus G, Garipov R, Addison CL, Shuhendler AJ. Mapping vitamin B 6 metabolism by hydrazoCEST magnetic resonance imaging. Chem Commun (Camb) 2021; 57:10867-10870. [PMID: 34665184 DOI: 10.1039/d1cc03704h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new CEST-MRI contrast agent, 2-HYNIC, capable of sensing aromatic aldehydes is reported. Pyridoxal 5'-phosphate, a key Vitamin B6 metabolite necessary for >140 biotransformations was mapped by CEST-MRI in vitro and in vivo in lung cancer. 2-HYNIC provided access to this key biomarker associated with a variety of human diseases.
Collapse
|
19
|
Kirby A. SP-0707 Adjuvant nodal irradiation in breast cancer. Radiother Oncol 2021. [DOI: 10.1016/s0167-8140(21)08685-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
20
|
Kirby A. Comment on: Systemic versus oral and systemic antibiotic prophylaxis (SOAP) study in colorectal surgery: prospective randomized multicentre trial. Br J Surg 2021; 108:e314. [PMID: 34077495 DOI: 10.1093/bjs/znab189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 04/18/2021] [Indexed: 11/13/2022]
|
21
|
Marta GN, Ramiah D, Kaidar-Person O, Kirby A, Coles C, Jagsi R, Hijal T, Sancho G, Zissiadis Y, Pignol JP, Ho AY, Cheng SHC, Offersen BV, Meattini I, Poortmans P. The Financial Impact on Reimbursement of Moderately Hypofractionated Postoperative Radiation Therapy for Breast Cancer: An International Consortium Report. Clin Oncol (R Coll Radiol) 2021; 33:322-330. [PMID: 33358283 DOI: 10.1016/j.clon.2020.12.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 11/06/2020] [Accepted: 12/08/2020] [Indexed: 12/16/2022]
Abstract
AIMS Moderately hypofractionated breast irradiation has been evaluated in several prospective studies, resulting in wide acceptance of shorter treatment protocols for postoperative breast irradiation. Reimbursement for radiation therapy varies between private and public systems and between countries, impacting variably financial considerations in the use of hypofractionation. The aim of this study was to evaluate the financial impact of moderately hypofractionated breast irradiation by reimbursement system in different countries. MATERIALS AND METHODS The study was designed by an international group of radiation oncologists. A web-questionnaire was distributed to representatives from each country. The participants were asked to involve the financial consultant at their institution. RESULTS Data from 13 countries from all populated continents were collected (Europe: Denmark, France, Italy, the Netherlands, Spain, UK; North America: Canada, USA; South America: Brazil; Africa: South Africa; Oceania: Australia; Asia: Israel, Taiwan). Clinicians and/or departments in most of the countries surveyed (77%) receive remuneration based on the number of fractions delivered to the patient. The financial loss per patient estimated resulting from applying moderately hypofractionated breast irradiation instead of conventional fractionation ranged from 5-10% to 30-40%, depending on the healthcare provider. CONCLUSION Although a generalised adoption of moderately hypofractionated breast irradiation would allow for a considerable reduction in social and economic burden, the financial loss for the healthcare providers induced by fee-for-service remuneration may be a factor in the slow uptake of these regimens. Therefore, fee-for-service reimbursement may not be preferable for radiation oncology. We propose that an alternative system of remuneration, such as bundled payments based on stage and diagnosis, may provide more value for all stakeholders.
Collapse
|
22
|
Ahmed S, Bonnett L, Melhuish A, Adil MT, Aggarwal I, Ali W, Bennett J, Boldock E, Burns FA, Czarniak E, Dennis R, Flower B, Fok R, Goodman AL, Halai S, Hanna T, Hashem M, Hodgson SH, Hughes G, Hurndall KH, Hyland R, Iqbal MR, Jarchow-MacDonald A, Kailavasan M, Klimovskij M, Laliotis A, Lambourne J, Lawday S, Lee F, Lindsey B, Lund JN, Mabayoje DA, Malik KI, Muir A, Narula HS, Ofor U, Parsons H, Pavelle T, Prescott K, Rajgopal A, Roy I, Sagar J, Scarborough C, Shaikh S, Smart CJ, Snape S, Tabaqchali MA, Tennakoon A, Tilley R, Vink E, White L, Burke D, Kirby A. Development and internal validation of clinical prediction models for outcomes of complicated intra-abdominal infection. Br J Surg 2021; 108:441-447. [PMID: 33615351 DOI: 10.1093/bjs/znaa117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 11/05/2020] [Indexed: 11/14/2022]
Abstract
BACKGROUND Complicated intra-abdominal infections (cIAIs) are associated with significant morbidity and mortality. The aim of this study was to describe the clinical characteristics of patients with cIAI in a multicentre study and to develop clinical prediction models (CPMs) to help identify patients at risk of mortality or relapse. METHODS A multicentre observational study was conducted from August 2016 to February 2017 in the UK. Adult patients diagnosed with cIAI were included. Multivariable logistic regression was performed to develop CPMs for mortality and cIAI relapse. The c-statistic was used to test model discrimination. Model calibration was tested using calibration slopes and calibration in the large (CITL). The CPMs were then presented as point scoring systems and validated further. RESULTS Overall, 417 patients from 31 surgical centres were included in the analysis. At 90 days after diagnosis, 17.3 per cent had a cIAI relapse and the mortality rate was 11.3 per cent. Predictors in the mortality model were age, cIAI aetiology, presence of a perforated viscus and source control procedure. Predictors of cIAI relapse included the presence of collections, outcome of initial management, and duration of antibiotic treatment. The c-statistic adjusted for model optimism was 0.79 (95 per cent c.i. 0.75 to 0.87) and 0.74 (0.73 to 0.85) for mortality and cIAI relapse CPMs. Adjusted calibration slopes were 0.88 (95 per cent c.i. 0.76 to 0.90) for the mortality model and 0.91 (0.88 to 0.94) for the relapse model; CITL was -0.19 (95 per cent c.i. -0.39 to -0.12) and - 0.01 (- 0.17 to -0.03) respectively. CONCLUSION Relapse of infection and death after complicated intra-abdominal infections are common. Clinical prediction models were developed to identify patients at increased risk of relapse or death after treatment, these now require external validation.
Collapse
|
23
|
Suchý M, Kirby A, Sabloff T, Mulvihill EE, Shuhendler AJ. Dansyl–NA 3 conjugates for glycoprotein detection through fluorescent tagging and native gel electrophoresis. NEW J CHEM 2021. [DOI: 10.1039/d1nj02393d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An aldehyde-reactive fluorophore has been prepared that can afford the fluorescent detection of serum glycoproteins by native gel electrophoresis.
Collapse
|
24
|
Patin NV, Peña-Gonzalez A, Hatt JK, Moe C, Kirby A, Konstantinidis KT. The Role of the Gut Microbiome in Resisting Norovirus Infection as Revealed by a Human Challenge Study. mBio 2020; 11:e02634-20. [PMID: 33203758 PMCID: PMC7683401 DOI: 10.1128/mbio.02634-20] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 10/16/2020] [Indexed: 12/11/2022] Open
Abstract
Norovirus infections take a heavy toll on worldwide public health. While progress has been made toward understanding host responses to infection, the role of the gut microbiome in determining infection outcome is unknown. Moreover, data are lacking on the nature and duration of the microbiome response to norovirus infection, which has important implications for diagnostics and host recovery. Here, we characterized the gut microbiomes of subjects enrolled in a norovirus challenge study. We analyzed microbiome features of asymptomatic and symptomatic individuals at the genome (population) and gene levels and assessed their response over time in symptomatic individuals. We show that the preinfection microbiomes of subjects with asymptomatic infections were enriched in Bacteroidetes and depleted in Clostridia relative to the microbiomes of symptomatic subjects. These compositional differences were accompanied by differences in genes involved in the metabolism of glycans and sphingolipids that may aid in host resilience to infection. We further show that microbiomes shifted in composition following infection and that recovery times were variable among human hosts. In particular, Firmicutes increased immediately following the challenge, while Bacteroidetes and Proteobacteria decreased over the same time. Genes enriched in the microbiomes of symptomatic subjects, including the adenylyltransferase glgC, were linked to glycan metabolism and cell-cell signaling, suggesting as-yet unknown roles for these processes in determining infection outcome. These results provide important context for understanding the gut microbiome role in host susceptibility to symptomatic norovirus infection and long-term health outcomes.IMPORTANCE The role of the human gut microbiome in determining whether an individual infected with norovirus will be symptomatic is poorly understood. This study provides important data on microbes that distinguish asymptomatic from symptomatic microbiomes and links these features to infection responses in a human challenge study. The results have implications for understanding resistance to and treatment of norovirus infections.
Collapse
|
25
|
Chick J, Mitchell A, Sullivan J, Herbert T, Lawes R, McNair H, Schmidt M, Nill S, Kirby A, Oelfke U. PO-1766: A clinical solution for electron streaming shielding for partial breast treatments on Unity MRlinac. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)01784-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|