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1.
Int J Mol Sci ; 25(14)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39062992

RESUMO

[123I]ß-methyl-p-iodophenyl-pentadecanoic acid ([123I]BMIPP), which is used for nuclear medicine imaging of myocardial fatty acid metabolism, accumulates in cancer cells. However, the mechanism of accumulation remains unknown. Therefore, this study aimed to elucidate the accumulation and accumulation mechanism of [123I]BMIPP in cancer cells. We compared the accumulation of [123I]BMIPP in cancer cells with that of [18F]FDG and found that [123I]BMIPP was a much higher accumulation than [18F]FDG. The accumulation of [123I]BMIPP was evaluated in the presence of sulfosuccinimidyl oleate (SSO), a CD36 inhibitor, and lipofermata, a fatty acid transport protein (FATP) inhibitor, under low-temperature conditions and in the presence of etomoxir, a carnitine palmitoyl transferase I (CPT1) inhibitor. The results showed that [123I]BMIPP accumulation was decreased in the presence of SSO and lipofermata in H441, LS180, and DLD-1 cells, suggesting that FATPs and CD36 are involved in [123I]BMIPP uptake in cancer cells. [123I]BMIPP accumulation in all cancer cell lines was significantly decreased at 4 °C compared to that at 37 °C and increased in the presence of etomoxir in all cancer cell lines, suggesting that the accumulation of [123I]BMIPP in cancer cells is metabolically dependent. In a biological distribution study conducted using tumor-bearing mice transplanted with LS180 cells, [123I]BMIPP highly accumulated in not only LS180 cells but also normal tissues and organs (including blood and muscle). The tumor-to-intestine or large intestine ratios of [123I]BMIPP were similar to those of [18F]FDG, and the tumor-to-large-intestine ratios exceeded 1.0 during 30 min after [123I]BMIPP administration in the in vivo study. [123I]BMIPP is taken up by cancer cells via CD36 and FATP and incorporated into mitochondria via CPT1. Therefore, [123I]BMIPP may be useful for imaging cancers with activated fatty acid metabolism, such as colon cancer. However, the development of novel imaging radiotracers based on the chemical structure analog of [123I]BMIPP is needed.


Assuntos
Neoplasias do Colo , Iodobenzenos , Animais , Humanos , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Camundongos , Linhagem Celular Tumoral , Iodobenzenos/química , Antígenos CD36/metabolismo , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/metabolismo , Radioisótopos do Iodo , Ácidos Oleicos/química , Miocárdio/metabolismo , Distribuição Tecidual , Proteínas de Transporte de Ácido Graxo/metabolismo , Fluordesoxiglucose F18/química , Fluordesoxiglucose F18/metabolismo , Ácidos Graxos
2.
Clin Nucl Med ; 49(5): 438-441, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574255

RESUMO

ABSTRACT: 123I-meta-iodobenzylguanidine (123I-MIBG) is extensively used for initial staging and response evaluation in children with neuroblastoma. Physiological uptake of 123I-MIBG occurs in the salivary glands, liver, adrenal gland, myocardium, bowel, and thyroid gland. 123I-MIBG cannot cross an intact blood-brain barrier. We present the rare case of a 3-year-old boy with neuroblastoma and meningeal metastases who underwent an 123I-MIBG scan for disease restaging that showed abnormal brain uptake. Abnormal MIBG uptake in the brain can occur if there is disruption of the blood-brain barrier either secondary to metastases or after damage to blood-brain barrier.


Assuntos
Iodobenzenos , Neuroblastoma , Pré-Escolar , Humanos , Masculino , 3-Iodobenzilguanidina , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Neuroblastoma/diagnóstico por imagem , Neuroblastoma/patologia , Cintilografia
3.
J Am Chem Soc ; 144(40): 18562-18574, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36179328

RESUMO

Recycling of critical materials, regeneration of waste, and responsible catalyst manufacture have been repeatedly documented as essential for a sustainable future with respect to the environment and energy production. Electrochemical methods have become increasingly recognized as capable of achieving these goals, and "impact" electrochemistry, with the advantages associated with dynamic nanoelectrodes, has recently emerged as a prime candidate for the recovery of metals from solution. In this report, the nanoimpact technique is used to generate carbon-supported palladium catalysts from low-concentration palladium(II) chloride solutions (i.e., a waste stream mimic) as a proof of concept. Subsequently, the catalytic properties of this material in both synthesis (Suzuki coupling reaction) and electrocatalysis (hydrogen evolution) are demonstrated. Transient reductive impact signals are shown and analyzed at potentials negative of +0.4 V (vs SCE) corresponding to the onset of palladium deposition in traditional voltammetry. Direct evidence of Pd modification was obtained through characterization by environmental scanning electron microscopy/energy-dispersive X-ray spectroscopy, inductively coupled plasma mass spectrometry, X-ray photoelectron spectroscopy, transmission electron microscopy, and thermogravimetric analysis of impacted particles. This showed the formation of deposits of Pd0 partially covering the 50 nm carbon black particles with approximately 14% Pd (wt %) under the conditions used. This material was then used to demonstrate the conversion of iodobenzene into its biphenyl product (confirmed through nuclear magnetic resonance) and the successful production of hydrogen as an electrocatalyst under acidic conditions (under cyclic voltammetry).


Assuntos
Iodobenzenos , Paládio , Carbono/química , Catálise , Cloretos , Eletroquímica , Hidrogênio , Oxirredução , Paládio/química , Fuligem
4.
J Chromatogr A ; 1681: 463465, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36116367

RESUMO

Myristicin [5-allyl-1­methoxy-2,3-(methylenedioxy)benzene] is the major constituent of the seasoning nutmeg oil and powder. Sometimes myristicin is abused via its ingestion at high doses to cause hallucination. In these high doses, myristicin could cause severe adverse health effects, including convulsion, delirium, and palpitation. Hence there is a strong need for a sensitive method for its analysis, such as fluorescence determination. Myristicin has a very weak fluorescence and also lacks derivatizable groups like the carboxylic, hydroxyl, or amino group in its structure, which makes its fluorescence derivatization challenging. In this research, we developed a fluorescence labeling method for myristicin based on the Mizoroki-Heck coupling reaction of its terminal alkene with a fluorescent aryl iodide derivative, 4-(4,5-diphenyl-1H-imidazol-2-yl)iodobenzene (DIB-I). Then, we developed an HPLC fluorescence detection method for the determination of myristicin utilizing this labeling reaction. The developed method showed a good linear response for myristicin (r = 0.995) in the range of 0.01-10 µmol/L with excellent sensitivity down to the detection limit of 2.9 nmol/L (9.6 fmol/injection). Finally, the developed method could be successfully applied to determine myristicin content in nutmeg powder, oil samples, and human plasma with simple extraction methods and good recoveries ranging from 89.3 to 106%.


Assuntos
Derivados de Alilbenzenos , Iodobenzenos , Myristica , Dioxolanos , Humanos , Iodetos , Pós
5.
Tech Coloproctol ; 26(11): 875-881, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35947241

RESUMO

BACKGROUND: Ileal pouch-anal anastomosis (IPAA) is the procedure of choice in patients with ulcerative colitis (UC) requiring surgery. Advantages of laparoscopic IPAA (lap-IPAA) compared to open surgery have been investigated. However, laparoscopic dissection in the pelvis is still a challenge. A transanal approach provides better access to lower pelvis and avoids multiple staple firings, which could reduce the risk of anastomotic complications. The aim of this study was to compare short-term outcomes of transanal proctectomy with IPAA (ta-IPAA) with conventional lap-IPAA in patients with UC. METHODS: A single-center retrospective study was conducted on consecutive UC patients, treated at Copenhagen University Hospital, Hvidovre, undergoing either laparoscopic or transanal IPAA in the period between January 2013 and December 2020. Exclusion criteria were Crohn's disease, previous extensive abdominal surgery and impaired sphincter function. Primary outcomes were overall postoperative complications. Secondary outcomes were length of hospital stay and re-admissions. For comparison between ta-IPAA and lap-IPAA, the Mann-Whitney U test was used for continuous variables, and Chi-square and Fisher's exact test for categorical variables. RESULTS: A total of 65 patients with ta-IPAA (34 males, 31 females, median age 31 years [range 12-66 years]) and 70 patients with lap-IPAA (35 males, 35 females, median age 26 years [range 12-66 years]) were included. There was no difference between ta-IPAA and lap-IPAA regarding age, sex, body mass index or American Society of Anesthesiologists class. The primary colectomy procedure was performed laparoscopically in 95% of the ta-IPPA and 91% of the lap-IPAA patients (p = 0.493). The mean time between total colectomy and IPAA was 15 and 9 weeks for ta-IPAA and lap-IPAA, respectively (p = 0.048). A higher proportion of patients with ta-IPAA were treated with biologics preoperatively (98 vs. 82%; p = 0.002). Patients with ta-IPAA had a significantly higher mean operative time compared to lap-IPAA (277 min vs. 224 min; p = 0.001). There was no difference in the overall postoperative complication rate (ta-IPAA: 23% vs. lap-IPAA: 23%; p = 0.99). Pouch-related complications occurred in 13% of the ta-IPAA patients and 29% of lap-IPPA patients (p = 0.402). There was no difference in the anastomotic leakage rates. Readmission rates were similar in the ta-IPAA and lap-IPAA group (26 vs. 29%; p = 0.85), including IPAA-related readmissions. The mean follow-up time was 24 and 75 months for ta-IPAA and lap-IPAA, respectively (p = 0.001), and the ileostomy closure rate was similar in both groups of patients (p = 0.96). CONCLUSIONS: The ta-IPAA approach for UC is a safe procedure and offers acceptable short-time outcomes.


Assuntos
Produtos Biológicos , Colite Ulcerativa , Bolsas Cólicas , Proctocolectomia Restauradora , Adolescente , Adulto , Idoso , Anastomose Cirúrgica/métodos , Criança , Colite Ulcerativa/complicações , Colite Ulcerativa/cirurgia , Feminino , Humanos , Iodobenzenos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Proctocolectomia Restauradora/efeitos adversos , Proctocolectomia Restauradora/métodos , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
6.
Molecules ; 27(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35566165

RESUMO

In this paper we describe a detailed mechanistic studies on the [FeII(PBO)2(CF3SO3)2] (1), [FeII(PBT)2(CF3SO3)2] (2), and [FeII(PBI)3](CF3SO3)2 (3)-catalyzed (PBO = 2-(2'-pyridyl)benzoxazole, PBT = 2-(2'-pyridyl)benzthiazole, PBI = 2-(2'-pyridyl)benzimidazole) Baeyer-Villiger oxidation of cycloketones by dioxygen with cooxidation of aldehydes and peroxycarboxylic acids, including the kinetics on the reactivity of (µ-1,2-peroxo)diiron(III), acylperoxo- and iodosylbenzene-iron(III) species as key intermediates.


Assuntos
Ferro , Oxigênio , Catálise , Compostos Ferrosos , Iodobenzenos , Oxirredução
7.
Chemphyschem ; 23(6): e202200011, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35099849

RESUMO

The effects on the C-I⋅⋅N halogen bond between iodobenzene and NH3 of placing various substituents on the phenyl ring are monitored by quantum calculations. Substituents R=N(CH3 )2 , NH2 , CH3 , OCH3 , COCH3 , Cl, F, COH, CN, and NO2 were each placed ortho, meta, and para to the I. The depth of the σ-hole on I is deepened as R becomes more electron-withdrawing which is reflected in a strengthening of the halogen bond, which varied between 3.3 and 5.5 kcal mol-1 . In most cases, the ortho placement yields the largest perturbation, followed by meta and then para, but this trend is not universal. Parallel to these substituent effects is a progressive lengthening of the covalent C-I bond. Formation of the halogen bond reduces the NMR chemical shielding of all three nuclei directly involved in the C-I⋅⋅N interaction. The deshielding of the electron donor N is most closely correlated with the strength of the bond, as is the coupling constant between I and N, so both have potential use as spectroscopic measures of halogen bond strength.


Assuntos
Halogênios , Iodobenzenos , Amônia , Benzeno , Elétrons , Halogênios/química
8.
Ann Nucl Med ; 36(3): 244-254, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34822103

RESUMO

OBJECTIVE: Myocardial ischemia is known to suppress fatty acid metabolism and favor glucose metabolism. However, changes in myocardial metabolism after coronary revascularization are not fully elucidated. METHODS: Thirty-eight patients with coronary artery disease were retrospectively enrolled. These patients had undergone stress perfusion single photon emission computed tomography (SPECT) and 123I-BMIPP SPECT in both the short-term (6.4 ± 4.7 months) and mid-term (29.9 ± 7.2 months) after isolated coronary artery bypass grafting. Tracer uptake was graded using a 17-segment, 5-point scoring model. Serial changes in SRS (summed rest score), SDS (summed difference score), the BMIPP score (total defect score of BMIPP), and the mismatch score (BMIPP score-SRS) were evaluated. In addition, persistent perfusion-metabolism mismatch (PM) was defined as mismatch score minus SDS of 3 or more during the mid-term postoperative period. The clinical parameters associated with PM were examined. RESULTS: From short- to mid-term postoperative period, the extent of infarcted myocardium (SRS) did not change significantly (7.8 ± 8.0 to 7.1 ± 7.0, P = 0.117). The extent of ischemic myocardium (SDS), the BMIPP score and the mismatch score, which reflects perfusion-metabolism mismatch, were significantly improved (2.0 ± 2.8 to 0.7 ± 1.0, P = 0.010; 12.2 ± 9.0 to 9.5 ± 7.9, P < 0.001; 4.4 ± 3.7 to 2.5 ± 2.6, P < 0.001; respectively). Remarkably, perfusion-metabolism mismatch persisted in 13 patients (34%) even in the mid-term postoperative period. eGFR and SYNTAX score were independent predictors of persistent perfusion-metabolic mismatch in multivariable analysis (OR = 0.951, 95% CI 0.898-0.985, P = 0.010 and OR = 1.126, 95% CI 1.011-1.254, P = 0.031, respectively). The mismatch score both in the short- and mid-term significantly correlated with SYNTAX score (r = 0.400 and r = 0.472, respectively). CONCLUSIONS: Fatty acid metabolism disturbance improved from short- to mid-term postoperative period in patients with successful reperfusion by coronary artery bypass grafting. However, in patients with severe atherosclerosis, impaired fatty acid metabolism was sustained until the mid-term postoperative period, even though ischemia had resolved.


Assuntos
Iodobenzenos , Isquemia Miocárdica , Ponte de Artéria Coronária/efeitos adversos , Ácidos Graxos/metabolismo , Humanos , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/cirurgia , Perfusão , Estudos Retrospectivos , Tomografia Computadorizada de Emissão de Fóton Único/métodos
9.
Shokuhin Eiseigaku Zasshi ; 62(6): 175-179, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34955467

RESUMO

Food can sometimes contain odors not normally associated with that food. These odors are called off-flavors, and cow milk is known to contain off-flavors such as hexanal depending on the feed or physical condition of the cows. We previously discovered and revealed the structure of 2-Iodo-4-methylphenol (2I4MP), an off-flavor component in commercially available cow milk. We were the first group to discover 2I4MP is an off-flavor component in cow milk.This study investigated the following three questions. First, what compounds serve as the starting materials in generating 2I4MP? Organic synthesis techniques were used to identify p-cresol as a candidate starting material. Second, how is 2I4MP generated in the cowshed? Using cow dung, we confirmed that 2I4MP was generated by the effects of iodine on cow dung. Based on these findings, measures were proposed to prevent contamination of cow milk by 2I4MP. Third, how is 2I4MP transferred to raw milk? 2I4MP movement was estimated by creating a desiccator-based model that showed 2I4MP is potentially transferred to raw milk in the cowshed. These involve that the iodine-based disinfectants, used to disinfect teats during milking, should not be used excessively. Furthermore, ensuring the disinfectants do not fall onto cow dung or bedding. Adopting these measures is vital for preventing contamination of cow milk by 2I4MP.


Assuntos
Iodo , Iodobenzenos , Animais , Bovinos , Feminino , Leite , Odorantes
10.
Phys Med Biol ; 66(22)2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34666321

RESUMO

Numerous commercial technologies for online treatment monitoring (OTM) in radiotherapy (RT) are currently available including electronic portal imaging device (EPID)in vivodosimetry (IVD), transmission detectors and log files analysis. Despite this, in the UK there exists limited guidance on how to implement and commission a system for clinical use or information about the resources required to set up and maintain a service. A Radiotherapy Special Interest Group working party, established by Institute of Physics and Engineering in Medicine was formed with a view to reassess the current practice for OTM in the UK and an aim to develop consensus guidelines for the implementation of a system. A survey distributed to Heads of Medical Physics at 71 UK RT departments investigated: availability of OTM in the UK; estimates of workload; clinical implementation; methods of analysis; quality assurance; and opinions on future directions. The survey achieved a 76% response rate and demonstrated that OTM is widely supported in the UK, with 87% of respondents indicating all patients should undergo OTM. EPID IVD (EIVD) was the most popular form of OTM. An active EIVD service was reported by 37% of respondents, with 84% believing it was the optimal solution. This demonstrates a steady increase in adoption since 2012. Other forms of OTM were in use but they had only been adopted by a minority of centres. Financial barriers and the increase of staff workload continue to hinder wider implementation in other centres. Device automation and integration is a key factor for successful future adoption and requires support between treatment machine and OTM manufacturers. The survey has provided an updated analysis on the use of OTM methods across the UK. Future guidance is recommended on commissioning, adoption of local tolerances and root-cause analysis strategies to assist departments intending to implement OTM.


Assuntos
Radioterapia de Intensidade Modulada , Humanos , Iodobenzenos , Maleimidas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Inquéritos e Questionários , Reino Unido
11.
Phys Med Biol ; 66(7)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33631729

RESUMO

Introduction/Background. Despite growing interest in magnetic resonance imaging (MRI), integration in external beam radiotherapy (EBRT) treatment planning uptake varies globally. In order to understand the current international landscape of MRI in EBRT a survey has been performed in 11 countries. This work reports on differences and common themes identified.Methods. A multi-disciplinary Institute of Physics and Engineering in Medicine working party modified a survey previously used in the UK to understand current practice using MRI for EBRT treatment planning, investigate how MRI is currently used and managed as well as identify knowledge gaps. It was distributed electronically within 11 countries: Australia, Belgium, Denmark, Finland, France, Italy, the Netherlands, New Zealand, Sweden, the UK and the USA.Results. The survey response rate within the USA was <1% and hence these results omitted from the analysis. In the other 10 countries the survey had a median response rate of 77% per country. Direct MRI access, defined as either having a dedicated MRI scanner for radiotherapy (RT) or access to a radiology MRI scanner, varied between countries. France, Italy and the UK reported the lowest direct MRI access rates and all other countries reported direct access in ≥82% of centres. Whilst ≥83% of centres in Denmark and Sweden reported having dedicated MRI scanners for EBRT, all other countries reported ≤29%. Anatomical sites receiving MRI for EBRT varied between countries with brain, prostate, head and neck being most common. Commissioning and QA of image registration and MRI scanners varied greatly, as did MRI sequences performed, staffing models and training given to different staff groups. The lack of financial reimbursement for MR was a consistent barrier for MRI implementation for RT for all countries and MR access was a reported important barrier for all countries except Sweden and Denmark.Conclusion. No country has a comprehensive approach for MR in EBRT adoption and financial barriers are present worldwide. Variations between countries in practice, equipment, staffing models, training, QA and MRI sequences have been identified, and are likely to be due to differences in funding as well as a lack of consensus or guidelines in the literature. Access to dedicated MR for EBRT is limited in all but Sweden and Denmark, but in all countries there are financial challenges with ongoing per patient costs. Despite these challenges, significant interest exists in increasing MR guided EBRT planning over the next 5 years.


Assuntos
Iodobenzenos , Humanos , Imageamento por Ressonância Magnética , Masculino , Maleimidas , Planejamento da Radioterapia Assistida por Computador/métodos
12.
Phys Med Biol ; 66(5)2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33450742

RESUMO

This document gives guidance for multidisciplinary teams within institutions setting up and using an MRI-guided radiotherapy (RT) treatment planning service. It has been written by a multidisciplinary working group from the Institute of Physics and Engineering in Medicine (IPEM). Guidance has come from the experience of the institutions represented in the IPEM working group, in consultation with other institutions, and where appropriate references are given for any relevant legislation, other guidance documentation and information in the literature. Guidance is only given for MRI acquired for external beam RT treatment planning in a CT-based workflow, i.e. when MRI is acquired and registered to CT with the purpose of aiding delineation of target or organ at risk volumes. MRI use for treatment response assessment, MRI-only RT and other RT treatment types such as brachytherapy and gamma radiosurgery are not considered within the scope of this document. The aim was to produce guidance that will be useful for institutions who are setting up and using a dedicated MR scanner for RT (referred to as an MR-sim) and those who will have limited time on an MR scanner potentially managed outside of the RT department, often by radiology. Although not specifically covered in this document, there is an increase in the use of hybrid MRI-linac systems worldwide and brief comments are included to highlight any crossover with the early implementation of this technology. In this document, advice is given on introducing a RT workload onto a non-RT-dedicated MR scanner, as well as planning for installation of an MR scanner dedicated for RT. Next, practical guidance is given on the following, in the context of RT planning: training and education for all staff working in and around an MR scanner; RT patient set-up on an MR scanner; MRI sequence optimisation for RT purposes; commissioning and quality assurance (QA) to be performed on an MR scanner; and MRI to CT registration, including commissioning and QA.


Assuntos
Radioterapia Guiada por Imagem , Humanos , Iodobenzenos , Imageamento por Ressonância Magnética , Maleimidas , Aceleradores de Partículas , Planejamento da Radioterapia Assistida por Computador
13.
Org Biomol Chem ; 19(5): 1133-1144, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33443507

RESUMO

The development of new approaches toward chemo- and regioselective functionalization of polycyclic aromatic hydrocarbon (PAH) scaffolds will provide opportunities for the synthesis of novel biologically active small molecules that exploit the high degree of lipophilicity imparted by the PAH unit. Herein, we report a new synthetic method for C-X bond substitution that is speculated to operate via a N-centered radical (NCR) mechanism according to experimental observations. A series of PAH sulfonamides have been synthesized and their biological activity has been evaluated against Gram-negative and Gram-positive bacterial strains (using a BacTiter-Glo assay) along with a series of mammalian cell lines (using CellTiter-Blue and CellTiter-Glo assays). The viability assays have resulted in the discovery of a number of bactericidal compounds that exhibit potency similar to other well-known antibacterials such as kanamycin and tetracycline, along with the discovery of a luciferase inhibitor. Additionally, the physicochemical and drug-likeness properties of the compounds were determined experimentally and using in silico approaches and the results are presented and discussed within.


Assuntos
Acetatos/química , Iodo/química , Iodobenzenos/química , Hidrocarbonetos Policíclicos Aromáticos/química , Sulfonamidas/síntese química , Sulfonamidas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Catálise , Linhagem Celular Tumoral , Técnicas de Química Sintética , Humanos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Sulfonamidas/química
14.
J Nucl Cardiol ; 28(1): 187-195, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-30603890

RESUMO

BACKGROUND: Simultaneous dual-tracer imaging using isotopes with close photo-peaks may benefit from improved properties of cadmium-zinc-telluride (CZT)-based scanners. METHODS: Thirty patients having undergone primary percutaneous coronary intervention for acute myocardial infarction underwent single-(99mTc-tetrofosmin (TF) or 123I-BMIPP first) followed by simultaneous 99mTc-TF /123I-BMIPP dual-tracer imaging using a Discovery NM/CT 670 CZT. The values for the quantitative gated-SPECT (QGS) and the quantitative perfusion SPECT (QPS) were assessed. RESULTS: The intra-class correlation (ICC) coefficients between the single- and dual-tracer imaging were high in all the QGS and QPS data (Summed motion score: 0.95, summed thickening score: 0.94, ejection fraction: 0.98, SRS for 99mTc-TF: 0.97/ for 123I-BMIPP: 0.95). Wall motion, wall thickening and rest scores per coronary-territory-based regions were also comparable between the single- and dual imaging (ICC coefficient > 0.91). The interrater concordance in the visual analysis for the infarction and perfusion-metabolism mismatch was significant for the global and regional left ventricle (P < 0.001). CONCLUSION: The quantitative/semi-quantitative values for global and regional left-ventricular function, perfusion, and fatty acid metabolism were closely comparable between the dual-tracer imaging and the single-tracer mode. These data suggests the feasibility of the novel CZT-based scanner for the simultaneous 99mTc-TF /123I-BMIPP dual-tracer acquisitions in clinical settings.


Assuntos
Ácidos Graxos , Radioisótopos do Iodo , Iodobenzenos , Infarto do Miocárdio/diagnóstico por imagem , Compostos Organofosforados , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Cádmio/metabolismo , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea , Sensibilidade e Especificidade , Telúrio/metabolismo , Zinco/metabolismo
15.
J Biomol Struct Dyn ; 39(12): 4398-4414, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32552396

RESUMO

Prompt and regioselective synthesis of eleven novel [1,2,4]triazolo[4,3-a]pyrimidines 2a-2k, via intramolecular oxidative-cyclization of 2-(2-arylidenehydrazinyl)-4-methyl-6-phenylpyrimidine derivatives 1a-1k has been demonstrated here using diacetoxy iodobenzene (DIB) as inexpensive and ecofriendly hypervalent iodine(III) reagent in CH2Cl2 at room temperature. Regiochemistry of final product has been established by developing single crystal and studied X-ray crystallographic data for two derivatives 2c and 2h without any ambiguity. These prominent [1,2,4]triazolo[4,3-a]pyrimidines were evaluated for human osteosarcoma bone cancer (MG-63) and breast cancer (MCF-7) cell lines using MTT assay to find potent antiproliferative agent and also on testicular germ cells to find potent apoptotic inducing activities. All compounds show significant cytotoxicity, particularly 3-(2,4-dichlorophenyl)-5-methyl-7-phenyl-[1,2,4]triazolo[4,3-a]pyrimidine (2g) was found significant apoptotic inducing molecule, as well as the most potent cytotoxic agent against bone cancer (MG-63) and breast cancer (MCF-7) cell lines with GI50 value 148.96 µM and 114.3 µM respectively. Molecular docking studies has been carried out to see the molecular interactions of synthesized compounds with the protein thymidylate synthase (PBD ID: 2G8D).Communicated by Ramaswamy H. Sarma.


Assuntos
Antineoplásicos , Iodobenzenos , Antineoplásicos/farmacologia , Apoptose , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Iodobenzenos/farmacologia , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirimidinas/farmacologia , Relação Estrutura-Atividade
16.
Mol Imaging Biol ; 22(2): 434-443, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31183841

RESUMO

PURPOSE: There is a continuous search for imaging techniques with high sensitivity and specificity for brain tumors. Positron emission tomography (PET) imaging has shown promise, though many PET agents either have a low tumor specificity or impractical physical half-lives. [124I]CLR1404 is a small molecule alkylphosphocholine analogue that is thought to bind to plasma membrane lipid rafts and has shown high tumor-to-background ratios (TBR) in a previous pilot study in brain tumor patients. This study attempts to define the clinical value of [124I]CLR1404 PET/CT (aka CLR124). PROCEDURES: Adult patients with new or suspected recurrence of high-grade primary or metastatic brain tumors (N = 27) were injected with [124I]CLR1404 followed by PET/CT at 6, 24, and 48 h. Standard uptake values (SUV) and TBR values were calculated for all time points. Uptake of [124I]CLR1404 was qualitatively assessed, compared with magnetic resonance imaging (MRI), and correlated with clinical outcome. Final diagnosis (N = 25) was established based on surgically resected tissue or long-term follow-up. RESULTS: Positive uptake with high TBR was detected in all but one patient with a final diagnosis of primary/recurrent brain tumor (12/13) and in less than half of patients with treatment-related changes (5/12). Concordance between [124I]CLR1404 uptake and contrast enhancement on MRI was seen in < 40 %, with no concordance between T2-hyperintensities and uptake. No significant difference in overall outcome was found between patients with and without [124I]CLR1404 uptake. CONCLUSIONS: The uptake pattern in these patients suggests a very high sensitivity of [124I]CLR1404 PET/CT for diagnosing tumor tissue; however, tumor specificity needs to be further defined. Relative lack of concordance with standard MRI characteristics suggests that [124I]CLR1404 PET/CT provides additional information about brain tumors compared to MRI alone, potentially improving clinical decision-making.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Radioisótopos do Iodo , Iodobenzenos , Microdomínios da Membrana/química , Metástase Neoplásica , Éteres Fosfolipídicos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/secundário , Tomada de Decisões , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico
17.
Mol Imaging Biol ; 22(2): 358-366, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31165385

RESUMO

PURPOSE: Sigma-1 receptors (S1Rs) are overexpressed in almost all human cancers, especially in breast cancers. 1-(4-Iodophenyl)-3-(2-adamantyl)guanidine (IPAG) is a validated high-affinity S1R antagonist. The objective of the current study is to evaluate the potential of iodine-124-labeled IPAG ([124I]IPAG) to image S1R-overexpressing tumors. PROCEDURES: [124I]IPAG was synthesized from a tributyltin precursor dissolved in ethanol using chloramine-T as oxidant. Purity was analyzed using HPLC. In vitro and in vivo studies were performed using the breast cancer cell line MCF-7. Competitive inhibition studies were performed using haloperidol and cold IPAG. Tumors were established in athymic nude mice by injecting 107 cells subcutaneously. Mice were imaged on micro-positron emission tomography (PET) at 4, 24, 48, 72, and 144 h post i.v. injection. Biodistribution studies were performed at same time points. In vivo tracer dilution studies were performed using excess of IPAG and haloperidol. The efficacy of [124I]IPAG to image tumors was evaluated in LNCaP tumor-bearing mice as well. RESULTS: [124I]IPAG was synthesized in quantitative yield and in vitro studies indicated that [124I]IPAG binding was specific to S1R. PET imaging studies in MCF7 tumor-bearing mice reveal that [124I]IPAG accumulates in tumor and is preferentially retained while clearing from non-target organs. The tumor to background increases with time, and tumors could be clearly visualized starting from 24 h post administration. Similar results were obtained in mice bearing LNCaP tumors. In vivo tracer dilution studies showed that the uptake of [124I]IPAG could be competitively inhibited by excess of IPAG and haloperidol. CONCLUSIONS: [124I]IPAG was synthesized successfully in high yields, and in vitro and in vivo studies demonstrate specificity of [124I]IPAG. [124I]IPAG shows specific accumulation in tumors with increasing tumor to background ratio at later time points and therefore has high potential for imaging S1R-overexpressing cancers.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Perfilação da Expressão Gênica , Guanidinas/química , Radioisótopos do Iodo , Iodobenzenos/química , Receptores sigma/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Células MCF-7 , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Distribuição Tecidual , Receptor Sigma-1
18.
Ann Nucl Med ; 33(12): 930-936, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31605355

RESUMO

OBJECTIVES: Information on the relationship between myocardial damage assessed by myocardial scintigraphy and prognosis in patients with Anderson-Fabry disease (AFD) is lacking. We therefore aimed to investigate the prognostic impacts of myocardial thallium-201 (201Tl) and iodine-123 beta-methyl 15-para-iodophenyl 3(R, S)-methylpentadecanoic acid (123I-BMIPP) dual scintigraphy in patients with AFD. METHODS: Eighteen consecutive patients with AFD underwent resting myocardial 201Tl/123I-BMIPP dual scintigraphy. Total defect scores (TDS) on both images were calculated visually according to the 17-segment model using a 5-point scoring system. The mismatch score (MS) was calculated as 'TDS on 123I-BMIPP-TDS on 201Tl'. RESULTS: Six major adverse cardiac events (MACEs) were recorded during a mean follow-up of 6.7 ± 4.2 years (three heart failure requiring hospitalization and three cardiac deaths). Left ventricular mass index, left atrial diameter, brain natriuretic peptide, TDS on 123I-BMIPP, and MS were all significantly greater in patients with MACEs compared with those without. Kaplan-Meier analysis indicated that high TDS on 123I-BMIPP and high MS were associated with poor event-free survival. CONCLUSION: TDS on 123I-BMIPP was a better prognostic determinant in patients with AFD than TDS on 201Tl. Myocardial 201Tl/123I-BMIPP dual scintigraphy may thus be a useful noninvasive modality for evaluating prognosis in patients with AFD.


Assuntos
Doença de Fabry/diagnóstico por imagem , Ácidos Graxos , Coração/diagnóstico por imagem , Iodobenzenos , Radioisótopos de Tálio , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Cintilografia
19.
Nucl Med Commun ; 40(11): 1130-1137, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31524763

RESUMO

OBJECTIVE: The use of cadmium-zinc-telluride-based scanners may increase the clinical feasibility of simultaneous dual-isotope imaging. In the current study, we sought to investigate a potential acquisition time in simultaneous Tc-tetrofosmin/I-ß-methyl-p-iodophenyl pentadecanoic acid dual-isotope imaging using a Discovery NM/CT 670 cadmium-zinc-telluride. METHODS: Simultaneous Tc-tetrofosmin/I-ß-methyl-p-iodophenyl pentadecanoic acid dual-isotope imaging was performed in 29 patients who had undergone primary percutaneous coronary intervention for acute myocardial infarction. Referenced images with an acquisition time of 65 s/view (16.25 min) were reframed to produce images with acquisition times of 33, 16, and 8 s/view. The values for the quantitative-gated single-photon emission computed tomography (SPECT) and the quantitative perfusion SPECT were compared. RESULTS: The quantitative-gated SPECT values for images with 33, 16, and 8 s/views showed good consistency with those for 65 s/view (the lower 95% confidence intervals for the intraclass correlation were ≥0.80). The quantitative perfusion SPECT values for Tc-tetrofosmin images with 33, 16, and 8 s/views also showed good consistency with those for 65 s/view; however, the quantitative perfusion SPECT values for I-ß-methyl-p-iodophenyl pentadecanoic acid images with an acquisition time of 8 s/view were not consistent with the reference acquisition time of 65 s/view. CONCLUSIONS: The quantitative-gated SPECT and quantitative perfusion SPECT values obtained from images with shorter acquisition times correlated with the values obtained from images with a reference acquisition time of 65 s/view; however, tracer-specific predisposition should be considered. These findings suggest that it is possible to reduce acquisition time when performing simultaneous Tc-tetrofosmin/I-ß-methyl-p-iodophenyl pentadecanoic acid dual-tracer imaging with the novel cadmium-zinc-telluride scanner.


Assuntos
Cádmio , Ácidos Graxos , Iodobenzenos , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/cirurgia , Compostos Organofosforados , Compostos de Organotecnécio , Intervenção Coronária Percutânea , Telúrio , Tomografia Computadorizada de Emissão de Fóton Único/instrumentação , Zinco , Doença Aguda , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
20.
Appl Radiat Isot ; 154: 108890, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31525597

RESUMO

DNA double-strand breaks (DSBs) of peripheral blood lymphocyte were prospectively assessed in 9 patients who were injected with 201Tl-chloride and 123I-beta-methyl-p-iodophenyl-pentadecanoic acid in dual-isotope imaging. Phosphorylated H2AX (γH2AX) was used as a biomarker for detecting DSBs, and the mean number of γH2AX foci per cell was measured microscopically. Mean γH2AX foci before administration of radiopharmaceuticals and at 3, 6, and 24 h following administration were 0.22 ±â€¯0.34, 0.10 ±â€¯0.14, 0.59 ±â€¯0.46, and 0.52 ±â€¯0.40, respectively (p = n.s. for all combinations).


Assuntos
Dano ao DNA , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Imagem de Perfusão do Miocárdio/efeitos adversos , Tomografia Computadorizada de Emissão de Fóton Único/efeitos adversos , Idoso , Biomarcadores/sangue , Quebras de DNA de Cadeia Dupla , Ácidos Graxos , Feminino , Histonas/sangue , Humanos , Radioisótopos do Iodo/efeitos adversos , Iodobenzenos , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio/métodos , Estudos Prospectivos , Compostos Radiofarmacêuticos/efeitos adversos , Radioisótopos de Tálio/efeitos adversos , Tomografia Computadorizada de Emissão de Fóton Único/métodos
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