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1.
Sci Total Environ ; 838(Pt 3): 156386, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35662599

RESUMO

Endocrine disruption results from exposure to chemicals that alter the function of the endocrine system in animals. Chronic 60 days of exposure to a low dose (0.1 µM) of ioxynil (IOX) or diethylstilbestrol (DES) via food was used to determine the effects of these chemicals on the physiology of the heart and thyroid follicles in juvenile zebrafish. Immunofluorescence analysis and subsequent 3D morphometric analysis of the zebrafish heart revealed that chronic exposure to IOX induced ventricle deformation and significant volume increase (p < 0.001). DES exposure caused a change in ventricle morphology, but volume was unaffected. Alongside, it was found that DES exposure upregulated endothelial related genes (angptl1b, mhc1lia, mybpc2a, ptgir, notch1b and vwf) involved in vascular homeostasis. Both IOX and DES exposure caused a change in thyroid follicle morphology. Notably, in IOX exposed juveniles, thyroid follicle hypertrophy was observed; and in DES-exposed fish, an enlarged thyroid field was present. In summary, chronic exposure of juvenile zebrafish to IOX and DES affected the heart and the thyroid. Given that both chemicals are able to change the morphology of the thyroid it indicates that they behave as endocrine disruptive chemicals (EDCs). Heart function dynamically changes thyroid morphology, and function and hence it is likely that the observed cardiac effects of IOX and DES are the source of altered thyroid status in these fish.


Assuntos
Disruptores Endócrinos , Peixe-Zebra , Animais , Dietilestilbestrol/toxicidade , Iodobenzenos , Nitrilas , Glândula Tireoide , Peixe-Zebra/fisiologia
2.
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
3.
Int J Mol Sci ; 23(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35563272

RESUMO

Obesity is a leading cause of preventable death and morbidity. To elucidate the mechanisms connecting metabolically active brown adipose tissue (BAT) and metabolic health may provide insights into methods of treatment for obesity-related conditions. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18FDG-PET/CT) is traditionally used to image human BAT activity. However, the primary energy source of BAT is derived from intracellular fatty acids and not glucose. Beta-methyl-p-iodophenylpentadecanoic acid (BMIPP) is a fatty acid analogue amenable to in vivo imaging by single photon emission computed tomography/CT (SPECT/CT) when radiolabeled with iodine isotopes. In this study, we compare the use of 18FDG-PET/CT and 125I-BMIPP-SPECT/CT for fat imaging to ascertain whether BMIPP is a more robust candidate for the non-invasive evaluation of metabolically active adipose depots. Interscapular BAT, inguinal white adipose tissue (iWAT), and gonadal white adipose tissue (gWAT) uptake of 18FDG and 125I-BMIPP was quantified in mice following treatment with the BAT-stimulating drug CL-316,243 or saline vehicle control. After CL-316,243 treatment, uptake of both radiotracers increased in BAT and iWAT. The standard uptake value (SUVmean) for 18FDG and 125I-BMIPP significantly correlated in these depots, although uptake of 125I-BMIPP in BAT and iWAT more closely mimicked the fold-change in metabolic rate as measured by an extracellular flux analyzer. Herein, we find that imaging BAT with the radioiodinated fatty acid analogue BMIPP yields more physiologically relevant data than 18FDG-PET/CT, and its conventional use may be a pivotal tool for evaluating BAT in both mice and humans.


Assuntos
Tecido Adiposo Marrom , Fluordesoxiglucose F18 , Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Marrom/metabolismo , Animais , Ácidos Graxos/metabolismo , Fluordesoxiglucose F18/metabolismo , Iodobenzenos , Camundongos , Obesidade/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único/métodos
4.
Molecules ; 27(3)2022 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35163992

RESUMO

To discover an efficient and convenient method to synthesize C2-arylacylated benzothiazoles as potential drug scaffolds, a novel [bis(trifluoroacetoxy)iodo]benzene(PIFA)/KOH synergistically promoted direct ring-opening C2-arylacylation reaction of 2H-benzothiazoles with aryl methyl ketones has been developed. Various substrates were tolerated under optimized conditions affording the C2-arylacylation products in 70-95% yields for 38 examples. A plausible mechanism was also proposed based on a series of controlled experiments.


Assuntos
Benzotiazóis/química , Hidróxidos/química , Iodobenzenos/química , Compostos de Potássio/química , Ácido Trifluoracético/química , Acetilação , Benzotiazóis/síntese química , Estrutura Molecular , Oxirredução
5.
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
6.
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
7.
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
8.
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
9.
Steroids ; 176: 108917, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34520798

RESUMO

Irradiation of dichloroethane solutions of different bile acids with diacetoxy(iodobenzene) and iodine followed by treatment of the resulting raw mixture with MCPBA led to the 41-50% yields of the corresponding dehomologated alcohols in an uncomplicated one-pot protocol that can be completed in less than one day of work.


Assuntos
Álcoois/síntese química , Ácidos e Sais Biliares/química , Álcoois/química , Iodo/química , Iodobenzenos/química , Estrutura Molecular
10.
Int J Cardiovasc Imaging ; 37(12): 3573-3581, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34224046

RESUMO

This study aimed to determine whether coronary artery calcium score (CACS) can be a prognostic indicator for the development of major adverse cardiac events (MACEs) and compare the value of CACS with that of the 123I-betamethyl-p-iodophenyl-pentadecanoic acid (123I-BMIPP) defect score (BDS) in patients with non-ischemic heart failure with preserved ejection fraction (NIHFpEF). Among 643 consecutive patients hospitalized due to acute heart failure, 108 (74 ± 13y) were identified to have NIHFpEF on non-contrast regular chest computed tomography and 123I-BMIPP single-photon emission computed tomography (SPECT). We evaluated whether CACS and BDS were associated with MACEs using multivariate Cox models. Thirty-two MACEs developed at a mean follow-up period of 2.4 years. CACS > 0 (hazard ratio [HR] 2.38, 95% confidence interval [CI] 1.02-5.54) and higher BDS (HR 16.00, 95% CI 5.88-43.49) were significantly associated with the development of MACEs. The proportion of patients who experienced MACEs was significantly higher in the CACS > 0 and high BDS group than in the CACS = 0 and low BDS group (3% vs. 75%, p < 0.001). CACS, as well as BDS, could serve as potential prognostic indicators in patients with NIHFpEF.


Assuntos
Doença da Artéria Coronariana , Insuficiência Cardíaca , Iodobenzenos , Cálcio , Doença da Artéria Coronariana/diagnóstico por imagem , Ácidos Graxos , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Radioisótopos do Iodo , Valor Preditivo dos Testes , Prognóstico , Volume Sistólico , Tomografia Computadorizada de Emissão de Fóton Único
11.
J Inorg Biochem ; 223: 111524, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34218127

RESUMO

Iodosylbenzene (PhIO) and its derivatives have attracted significant attention due to their various applications in organic synthesis and biomimetic studies. For example, PhIO has been extensively used for generating high-valent metal-oxo species that have been regarded as key intermediates in diverse oxidative reactions in biological system. However, recent studies have shown that metal-iodosylbenzene adduct, known as a precursor of metal-oxo species, plays an important role in transition metal-catalyzed oxidation reactions. During last few decades, extensive investigations have been conducted on the synthesis and reactivity studies of metal-iodosylbenzene adducts with early and middle transition metals including manganese, iron, cobalt. Nevertheless, metal-iodosylbenzene adducts with late transition metals such as nickel, copper and zinc, still remains elusive. Herein, we report a novel copper(II)-iodosylbenzene adduct bearing a linear ligand composed of two pyridine rings and an ethoxyethanol side-chain, [Cu(OIPh)(HN3O2)]2+ (1). The copper(II)-iodosylbenzene adduct was characterized by several spectroscopic methods including UV-vis spectroscopy, electrospray ionization mass spectrometer (ESI MS), and electron paramagnetic resonance (EPR) combined with theoretical calculations. Interestingly, 1 can carry out the catalytic sulfoxidation reaction. In sulfoxidation reaction with thioanisole under catalytic reaction condition, not only two-electron but also four-electron oxidized products such sulfoxide and sulfone were yielded, respectively. However, 1 was not an efficient oxidant towards CH bond activation and epoxidation reactions due to the steric hindrance created by the intramolecular H-bonding interaction between HN3O2 ligand and iodosylbenzene moiety.


Assuntos
Complexos de Coordenação/química , Iodobenzenos/química , Catálise , Complexos de Coordenação/síntese química , Cobre/química , Cicloexenos/química , Teoria da Densidade Funcional , Iodobenzenos/síntese química , Modelos Químicos , Oxirredução , Estireno/química , Sulfetos/química
12.
J Am Chem Soc ; 143(25): 9338-9342, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34143634

RESUMO

We report Pd-catalyzed annulations of in situ generated strained cyclic allenes. This methodology employs aryl halides and cyclic allene precursors as the reaction partners in order to generate fused heterocyclic products. The annulation proceeds via the formation of two new bonds and an sp3 center. Moreover, both diastereo- and enantioselective variants of this methodology are validated, with the latter ultimately enabling the rapid enantioselective synthesis of a complex hexacyclic product. Studies leveraging transition metal catalysis to intercept cyclic allenes represent a departure from the more common, historical modes of cyclic allene trapping that rely on nucleophiles or cycloaddition partners. As such, this study is expected to fuel the development of reactions that strategically merge transition metal catalysis and transient strained intermediate chemistry for the synthesis of complex scaffolds.


Assuntos
Alcadienos/química , Compostos Heterocíclicos com 3 Anéis/síntese química , Acetatos/química , Catálise , Ciclização , Indóis/química , Iodobenzenos/química , Compostos Organometálicos/química , Paládio/química , Piridinas/química , Estereoisomerismo
13.
Mikrochim Acta ; 188(6): 194, 2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-34013434

RESUMO

The emergence and development of low-cost and high-efficiency nanozymes are promising to replace natural enzymes promoting the application of chemiluminescence immunoassays. Herein, a rapid and highly sensitive flow injection chemiluminescence immunoassay based on cobalt hydroxide (Co(OH)2) nanozyme was established to detect enrofloxacin (ENR) residues in food. In this system, Co(OH)2 nanosheets act as nanozymes to catalyze and amplify the chemiluminescence signal of the luminol-PIP-H2O2 system, as well as a carrier for immobilizing antibodies to form stable immunoprobes. In addition, carboxyl resin beads with good stability and biocompatibility were used as the base of the immunosensor to carry more coating antigens, based on the principle of competitive immunity and to achieve the rapid detection of ENR. Under optimal conditions, the linear working range is 0.0001 ~ 1000 ng/mL, and the limit of detection (LOD) is 0.041 pg/mL (S/N = 3). The method has been successfully applied to the analysis of aquatic products and poultry food. A non-enzyme immunosensor using Co(OH)2 nanosheets as antibody-conjugated carriers and peroxidase mimics for catalytic amplification of the chemiluminescence signal of luminol and using carboxyl resin beads as platform was designed to detect ENR residues in food.


Assuntos
Antibacterianos/análise , Cobalto/química , Enrofloxacina/análise , Hidróxidos/química , Imunoensaio/métodos , Nanoestruturas/química , Animais , Antibacterianos/imunologia , Anticorpos Imobilizados/imunologia , Catálise , Galinhas , Patos , Enrofloxacina/imunologia , Contaminação de Alimentos/análise , Peróxido de Hidrogênio/química , Iodobenzenos/química , Limite de Detecção , Luminescência , Substâncias Luminescentes/química , Medições Luminescentes , Luminol/química , Alimentos Marinhos/análise
15.
J Nucl Cardiol ; 28(3): 919-929, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33728571

RESUMO

BACKGROUND: We analyzed 18F-Fludeoxyglucose positron emission tomography (FDG-PET) and 123I-betamethyl-p-iodophenyl-pentadecanoic acid (BMIPP) single-photon emission computed tomography (SPECT) performed for cardiac sarcoidosis (CS) patients taking prednisolone, identified recurrence by FDG-PET, and investigated BMIPP as a recurrence and prognostic factor in CS. METHODS AND RESULTS: CS patients who underwent BMIPP and FDG-PET within 2 months were enrolled. The recurrence-free group included patients with standardized uptake value (SUVmax) < 4 in the myocardium consecutively for ≥ 2 years. The total BMIPP SPECT defect score (BDS) was used to estimate myocardial damage. The predictability of the initial BDS and SUVmax for major adverse cardiac events (MACE) was analyzed using Kaplan-Meier analysis. Overall, 73 patients and 250 BMIPP and FDG-PET sets were analyzed retrospectively (mean follow-up, 3.5 years). The BDS was significantly greater for the recurrence group (N = 21) vs recurrence-free group (20 ± 13 vs 14 ± 12, P = 0.041). Patients with BDS ≥16 had a significantly higher MACE rate than patients with BDS < 16 (log-rank test, P = 0.016). However, MACE occurrence was comparable between patients with SUVmax ≥ 4 and < 4. CONCLUSIONS: BDS is a predictive marker of recurrence and MACE. SUV is not related to MACE. Recurrence, defined by prednisolone treatment-induced SUV variability, was observed in approximately 30% of CS patients.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Ácidos Graxos , Fluordesoxiglucose F18 , Iodobenzenos , Tomografia por Emissão de Pósitrons , Sarcoidose/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Cardiomiopatias/tratamento farmacológico , Feminino , Glucocorticoides/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prednisolona/uso terapêutico , Prognóstico , Compostos Radiofarmacêuticos , Recidiva , Estudos Retrospectivos , Sarcoidose/tratamento farmacológico
16.
J Org Chem ; 86(7): 5292-5304, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33706517

RESUMO

A three-component reaction of olefin, diselenide and water, alcohols, phenol, carboxylic acid, or amine by a commercially available hypervalent iodine(III) reagent, PhIO, was developed. This method provides access to a wide range of vicinally functionalized selenoderivatives under ambient conditions with mostly excellent yields and high diastereoselectivity. The developed reaction displays high levels of functional group compatibility and is suitable for the late-stage functionalization of styrene-functionalized biomolecules. Preliminary investigations on the mechanism of the reaction are also presented.


Assuntos
Alcenos , Iodobenzenos , Álcoois , Estrutura Molecular
17.
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
18.
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
19.
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
20.
Ann Nucl Med ; 35(1): 59-64, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33030639

RESUMO

OBJECTIVE: 123I-15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid ([123I]BMIPP), a fatty acid analog, is widely used for the diagnosis of cardiac diseases. Feeding condition is one of the important factors in the myocardial fatty acid uptake, which may also affect myocardial accumulation of [123I]BMIPP and image quality of [123I]BMIPP scintigraphy. However, the relationship between the myocardial accumulation of [123I]BMIPP and the feeding condition is not entirely clear. Therefore, we determined the myocardial accumulation of [125I]BMIPP in mice at various metabolic statuses induced by fasting in comparison with the hepatic accumulation. METHODS: Fed or fasted (6-, 12-, and 24-h fasted) mice were intravenously injected with [125I]BMIPP (35.2-75.0 kBq, 4 nmol). Radioactivities in the heart and liver were measured at 1, 5, 10, 30, 60, and 120 min after the injection (n = 5-15/time point for each group), and then, the heart-to-liver (H/L) ratios were calculated. RESULTS: The myocardial accumulation level of [125I]BMIPP in the fed group was almost the same as that in the 6-h-fasted group at each time point, although it was decreased by 12- and 24-h fasting. The H/L ratios of [125I]BMIPP accumulation level were significantly decreased by fasting (1.92 ± 0.22, 1.45 ± 0.13, 1.12 ± 0.13, and 0.91 ± 0.15 at 10 min, and 3.30 ± 0.62, 2.09 ± 0.35, 1.79 ± 0.34, and 1.27 ± 0.06 at 30 min after the injection, respectively, for the fed group and the 6-, 12-, and 24-h-fasted groups; p < 0.0001), largely owing to the increase in the hepatic accumulation level in the fasting groups. CONCLUSION: Although short-period (6 h) fasting did not affect the myocardial accumulation level of [125I]BMIPP, the hepatic accumulation level was increased. The present results indicate that the fed condition may provide higher-contrast images in myocardial [123I]BMIPP scintigraphy.


Assuntos
Ácidos Graxos/metabolismo , Comportamento Alimentar , Radioisótopos do Iodo , Iodobenzenos/metabolismo , Fígado/metabolismo , Miocárdio/metabolismo , Animais , Jejum , Feminino , Masculino , Camundongos
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