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1.
Res Sq ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38343820

RESUMO

Fluorescence guided surgery (FGS) facilitates real time tumor delineation and is being rapidly established clinically. FGS efficacy is tied to the utilized dye and provided tumor contrast over healthy tissue. Apoptosis, a cancer hallmark, is a desirable target for tumor delineation. Here, we preclinically in vitro and in vivo, validate an apoptosis sensitive commercial carbocyanine dye (CJ215), with absorption and emission spectra suitable for near infrared (NIR, 650-900nm) and shortwave infrared (SWIR, 900-1700nm) fluorescence imaging (NIRFI, SWIRFI). High contrast SWIRFI for solid tumor delineation is demonstrated in multiple murine and human models including breast, prostate, colon, fibrosarcoma and intraperitoneal colorectal metastasis. Organ necropsy and imaging highlighted renal clearance of CJ215. SWIRFI and CJ215 delineated all tumors under ambient lighting with a tumor-to-muscle ratio up to 100 and tumor-to-liver ratio up to 18, from 24 to 168 h post intravenous injection with minimal uptake in healthy organs. Additionally, SWIRFI and CJ215 achieved non-contact quantifiable wound monitoring through commercial bandages. CJ215 provides tumor screening, guided resection, and wound healing assessment compatible with existing and emerging clinical solutions.

2.
ACS Nano ; 17(7): 6178-6192, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36971591

RESUMO

Macrophages comprise a significant portion of the immune cell compartment within tumors and are known contributors to tumor pathology; however, cancer immunotherapies targeting these cells are not clinically available. The iron oxide nanoparticle, ferumoxytol (FH), may be utilized as a nanophore for drug delivery to tumor-associated macrophages. We have demonstrated that a vaccine adjuvant, monophosphoryl lipid A (MPLA), can be stably captured within the carbohydrate shell of ferumoxytol without chemical modification of either the drug or the nanophore. This drug-nanoparticle combination (FH-MPLA) activated macrophages to an antitumorigenic phenotype at clinically relevant concentrations. In the immunotherapy-resistant B16-F10 model of murine melanoma, FH-MPLA treatment induced tumor necrosis and regression in combination with agonistic α-CD40 monoclonal antibody therapy. FH-MPLA, composed of clinically approved nanoparticle and drug payload, represents a potential cancer immunotherapy with translational relevance. FH-MPLA may be useful as an adjunctive therapy to existing antibody-based cancer immunotherapies which target only lymphocytic cells, reshaping the tumor immune environment.


Assuntos
Anticorpos Monoclonais , Melanoma , Camundongos , Animais , Preparações Farmacêuticas , Anticorpos Monoclonais/farmacologia , Óxido Ferroso-Férrico , Imunoterapia , Melanoma/tratamento farmacológico
3.
J Nucl Med ; 64(1): 177-182, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35738902

RESUMO

Medical radioisotopes produce Cerenkov luminescence (CL) from charged subatomic particles (ß+/-) traveling faster than light in dielectric media (e.g., tissue). CL is a blue-weighted and continuous emission, decreasing proportionally to increasing wavelength. CL imaging (CLI) provides an economic PET alternative with the advantage of also being able to image ß- and α emitters. Like any optical modality, CLI is limited by the optical properties of tissue (scattering, absorption, and ambient photon removal). Shortwave-infrared (SWIR, 900-1700 nm) CL has been detected from MeV linear accelerators but not yet from keV medical radioisotopes. Methods: Indium-gallium-arsenide sensors and SWIR lenses were mounted onto an ambient light-excluding preclinical enclosure. An exposure and processing pipeline was developed for SWIR CLI and then performed across 6 radioisotopes at in vitro and in vivo conditions. Results: SWIR CL was detected from the clinical radioisotopes 90Y, 68Ga, 18F, 89Zr, 131I, and 32P (biomedical research). SWIR CLI's advantage over visible-wavelength (VIS) CLI (400-900 nm) was shown via increased light penetration and decreased scattering at depth. The SWIR CLI radioisotope sensitivity limit (8.51 kBq/µL for 68Ga), emission spectrum, and ex vivo and in vivo examples are reported. Conclusion: This work shows that radioisotope SWIR CLI can be performed with unmodified commercially available components. SWIR CLI has significant advantages over VIS CLI, with preserved VIS CLI features such as radioisotope radiance levels and dose response linearity. Further improvements in SWIR optics and technology are required to enable widespread adoption.


Assuntos
Radioisótopos de Gálio , Luminescência , Radioisótopos , Tomografia por Emissão de Pósitrons/métodos
4.
Fungal Biol ; 125(12): 951-961, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34776232

RESUMO

Despite its status as a highly-prized and coveted fungi in gastronomy, many aspects of the subterranean life cycle of the Burgundy truffle (Tuber aestivum) are still unknown, because in situ observations of the formation and maturation of truffle fruitbodies remain difficult. Here, we adopted a suite of archaeological fine-scale excavating techniques to provide unique spatiotemporal snapshots of Burgundy truffle growth at three sites in southern Germany. We also recorded the relative position, fresh weight, maturity level and genotype composition of all excavated fruitbodies. Varying by a factor of thousand, the fresh weight of 73 truffle ranged from 0.1 to 103.2 g, with individual maturity levels likely representing different life cycle stages from completely unripe to fully ripe and even decaying. While only a slightly positive relationship between fruitbody weight and maturity level was found, our results suggest that genetically distinct specimens can exhibit different life cycle stages at the same period of time and under the same environmental conditions. We therefore argue that truffles are likely able to grow, mature and ripe simultaneously between early summer and late winter of the following year. Our case study should encourage further eco-archaeological truffle excavations under different biogeographic settings and at different seasons of the year to gain deeper insights into the fungi's subterranean ecology. The expected cross-disciplinary findings will help truffle hunters and farmers to improve their harvest practices and management strategies.


Assuntos
Micorrizas , Alemanha , Estações do Ano
5.
BMJ Open ; 11(9): e048144, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593491

RESUMO

INTRODUCTION: The primary objective of the ReIMAGINE Prostate Cancer Screening Study is to explore the uptake of an invitation to prostate cancer screening using MRI. METHODS AND ANALYSIS: The ReIMAGINE Prostate Cancer Screening Study is a prospective single-centre feasibility study. Eligible men aged 50-75 years with no prior prostate cancer diagnosis or treatment will be identified through general practitioner practices and randomly selected for invitation. Those invited will be offered an MRI scan and a prostate-specific antigen (PSA) blood test. The screening MRI scan consists of T2-weighted, diffusion-weighted and research-specific sequences, without the use of intravenous contrast agents. Men who screen positive on either MRI or PSA density will be recommended to have standard of care (National Health Service) tests for prostate cancer assessment, which includes multiparametric MRI. The study will assess the acceptability of an MRI-based prostate screening assessment and the prevalence of cancer detected in MRI-screened men. Summary statistics will be used to explore baseline characteristics in relation to acceptance rates and prevalence of cancer. ETHICS AND DISSEMINATION: ReIMAGINE Prostate Cancer Screening is a single-site screening study to assess the feasibility of MRI as a screening tool for prostate cancer. Ethical approval was granted by London-Stanmore Research Ethics Committee Heath Research Authority (reference 19/LO/1129). Study results will be published in peer-reviewed journals after completion of data analysis and used to inform the design of a multicentre screening study in the UK. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT04063566).


Assuntos
Antígeno Prostático Específico , Neoplasias da Próstata , Idoso , Detecção Precoce de Câncer , Estudos de Viabilidade , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico por imagem , Medicina Estatal
7.
Microorganisms ; 8(10)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096901

RESUMO

Coffee is one of the most traded commodities in the world. It plays a significant role in the global economy, employing over 125 million people. However, it is possible that this vital crop is threatened by changing climate conditions and fungal infections. This paper reviews how suitable areas for coffee cultivation and the toxigenic fungi species of Aspergillus, Penicillium, and Fusarium will be affected due to climate change. By combining climate models with species distribution models, a number of studies have investigated the future distribution of coffee cultivation. Studies predict that suitable coffee cultivation area could drop by ~50% under representation concentration pathway (RCP) 6.0 by 2050 for both Arabica and Robusta. These findings agree with other studies which also see an altitudinal migration of suitable cultivation areas to cooler regions, but limited scope for latitudinal migration owing to coffee's inability to tolerate seasonal temperature changes. Increased temperatures will see an overall increase in mycotoxin production such as aflatoxins, particularly in mycotoxigenic fungi (e.g., Aspergillus flavus) more suited to higher temperatures. Arabica and Robusta's limited ability to relocate means both species will be grown in less suitable climates, increasing plant stress and making coffee more susceptible to fungal infection and mycotoxins. Information regarding climate change parameters with respect to mycotoxin concentrations in real coffee samples is provided and how the changed climate affects mycotoxins in non-coffee systems is discussed. In a few areas where relocating farms is possible, mycotoxin contamination may decrease due to the "parasites lost" phenomenon. More research is needed to include the effect of mycotoxins on coffee under various climate change scenarios, as currently there is a significant knowledge gap, and only generalisations can be made. Future modelling of coffee cultivation, which includes the influence of atmospheric carbon dioxide fertilisation and forest management, is also required; however, all indications show that climate change will have an extremely negative effect on future coffee production worldwide in terms of both a loss of suitable cultivation areas and an increase in mycotoxin contamination.

8.
J Nucl Med ; 61(12): 1845-1850, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32444378

RESUMO

Trametinib is an extremely potent allosteric inhibitor of mitogen-activated protein kinase (MAPK)/extracellular-signal-regulated kinase (ERK) (MEK) 1/2, which has been approved for treatment of metastatic melanoma and anaplastic thyroid cancer in patients with confirmed BRAFV600E/K mutations. Though trametinib is highly efficacious, adverse side effects, including skin, gastrointestinal, and hepatic toxicity, are dose-limiting and can lead to treatment termination. Development of a noninvasive tool to visualize and quantify the delivery and distribution of trametinib (either as a single agent or in combination with other therapeutics) to tumors and organs would be helpful in assessing therapeutic index, personalizing individual dose, and potentially predicting resistance to therapy. Methods: To address these issues, we have developed a radiolabeled trametinib and evaluated the in vitro and in vivo properties. 123I-, 124I-, and 131I-trametinib, pure tracer analogs to trametinib, were synthesized in more than 95% purity, with an average yield of 69.7% and more than 100 GBq/µmol specific activity. Results: Overall, 124I-trametinib uptake in a panel of cancer cell lines can be blocked with cold trametinib, confirming specificity of the radiotracer in vitro and in vivo. 124I-trametinib was taken up at higher rates in KRAS and BRAF mutant cell lines than in wild-type KRAS cancer cell lines. In vivo, biodistribution revealed high uptake in the liver 2 h after injection, followed by clearance through the gastrointestinal tract over 4 d. Importantly, uptake higher than expected was observed in the lung and heart for up to 24 h. Peak uptake in the skin and gastrointestinal tract was observed between 6 and 24 h, whereas in B16F10 melanoma-bearing mice peak tumor concentrations were achieved between 24 and 48 h. Tumor uptake relative to muscle and skin was relatively low, peaking at 3.4- to 8.1-fold by 72 h, respectively. The biodistribution of 124I-trametinib was significantly reduced in mice on trametinib therapy, providing a quantitative method to observe MEK inhibition in vivo. Conclusion:124I-trametinib serves as an in vivo tool to personalize the dose instead of using the current single-fixed-dose scheme and, when combined with radiomic data, to monitor the emergence of therapy resistance. In addition, the production of iodinated trametinib affords researchers the ability to measure drug distribution for improved drug delivery studies.


Assuntos
Resistencia a Medicamentos Antineoplásicos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Radioisótopos do Iodo/química , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Tomografia por Emissão de Pósitrons , Piridonas/química , Piridonas/síntese química , Pirimidinonas/química , Pirimidinonas/síntese química , Linhagem Celular Tumoral , Técnicas de Química Sintética , Ativação Enzimática , Humanos , Traçadores Radioativos
9.
Quant Imaging Med Surg ; 9(10): 1628-1640, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31728307

RESUMO

BACKGROUND: The aim of this study was to translate dynamic glucose enhancement (DGE) body magnetic resonance imaging (MRI) based on the glucose chemical exchange saturation transfer (glucoCEST) signal to a 3 T clinical field strength. METHODS: An infusion protocol for intravenous (i.v.) glucose was optimised using a hyperglycaemic clamp to maximise the chances of detecting exchange-sensitive MRI signal. Numerical simulations were performed to define the optimum parameters for glucoCEST measurements with consideration to physiological conditions. DGE images were acquired for patients with lymphomas and prostate cancer injected i.v. with 20% glucose. RESULTS: The optimised hyperglycaemic clamp infusion based on the DeFronzo method demonstrated higher efficiency and stability of glucose delivery as compared to manual determination of glucose infusion rates. DGE signal sensitivity was found to be dependent on T2, B1 saturation power and integration range. Our results show that motion correction and B0 field inhomogeneity correction are crucial to avoid mistaking signal changes for a glucose response while field drift is a substantial contributor. However, after B0 field drift correction, no significant glucoCEST signal enhancement was observed in tumour regions of all patients in vivo. CONCLUSIONS: Based on our simulated and experimental results, we conclude that glucose-related signal remains elusive at 3 T in body regions, where physiological movements and strong effects of B1 + and B0 render the originally small glucoCEST signal difficult to detect.

10.
J Mater Chem B ; 5(32): 6637-6644, 2017 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32264426

RESUMO

Carbon nanotube-based molecular probes, imaging agents, and biosensors in cells and in vivo continue to garner interest as investigational tools and clinical devices due to their unique photophysical properties. Surface chemistry modulation of nanotubes plays a critical role in determining stability and interaction with biological systems both in vitro and in vivo. Among the many parameters that influence the biological fate of nanomaterials, surface charge is particularly influential due to direct electrostatic interactions with components of the cell membrane as well as proteins in the serum, which coat the nanoparticle surface in a protein corona and alter nanoparticle-cell interactions. Here, we modulated functional moieties on a helical polycarbodiimide polymer backbone that non-covalently suspended the nanotubes in aqueous media. By derivatizing the polymer with either primary amine or carboxylic acid side chains, we obtained nanotube complexes that present net surface charges of opposite polarity at physiological pH. Using these materials, we found that the uptake of carbon nanotubes in these cells is highly dependent on charge, with cationic nanotubes efficiently internalized into cells compared to the anionic nanotubes. Furthermore, we found that serum proteins drastically influenced cell uptake of the anionic nanotubes, while the effect was not prominent for the cationic nanotubes. Our findings have implications for improved engineering of drug delivery devices, molecular probes, and biosensors.

11.
Biochem J ; 382(Pt 2): 481-9, 2004 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-15200388

RESUMO

LAMP-1 (lysosome-associated membrane protein), a major glycoprotein present in the lysosomal membrane, constitutes up to 50% of total membrane proteins. LAMP-1, expressed at the plasma membrane, is reported to be the major molecule expressing the sialyl-Lewis X antigen. Two forms of LAMP-1 exist; the full-length LAMP-1 [LAMP-1 (+Tail)] has a highly glycosylated lumenal domain, a membrane-spanning domain and a short cytoplasmic tail, and the truncated LAMP-1 [LAMP-1 (-Tail)] contains only the lumenal domain. Soluble LAMP-1 (+/-Tail) has been reported in circulation. LAMP-1 at the cell surface has been shown to interact with E-selectin and galectin and is proposed to function in cell-cell interactions. However, the functional role(s) of soluble LAMP-1 in circulation is unclear. To investigate the functional role of soluble LAMP-1 in circulation, recombinant LAMP-1 (-Tail) and LAMP-1 (+Tail) were produced in HT1080 cells. Two immune-quantification assays were developed to distinguish between the LAMP-1 forms. The interaction and aggregation properties of the different LAMP-1 forms were investigated using the immune-quantification assays. Only LAMP-1 (+Tail) was found to aggregate and interact with plasma proteins. Plasma proteins that interact with LAMP-1 were isolated by affinity chromatography with either the recombinant LAMP-1 (-Tail) or a synthesized peptide consisting of the 14 amino acids of the LAMP-1 cytoplasmic tail. Transthyretin was found to interact with the cytoplasmic tail of LAMP-1. Transthyretin exists as a homotetramer in plasma, as such may play a role in the aggregation of LAMP-1 in circulation.


Assuntos
Antígenos CD/metabolismo , Pré-Albumina/metabolismo , Processamento Alternativo/genética , Antígenos CD/sangue , Antígenos CD/química , Antígenos CD/imunologia , Proteínas Sanguíneas/metabolismo , Linhagem Celular Tumoral , Ácidos Cólicos/farmacologia , Fibrossarcoma/química , Fibrossarcoma/genética , Fibrossarcoma/patologia , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Proteínas de Membrana Lisossomal , Isoformas de Proteínas/sangue , Isoformas de Proteínas/química , Isoformas de Proteínas/imunologia , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo
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