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1.
Clin Radiol ; 77(10): e711-e718, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948490

RESUMO

AIM: To assess if radiomic feature analysis could help to differentiate between the lipid-poor adenomas and metastases to the adrenal glands. MATERIALS AND METHODS: Eighty-six patients (women:men 42:44; mean age 66 years) with biopsy-proven adrenal metastases and 55 patients (women:men 39:16; mean age 67 years) with lipid-poor adenomas who underwent contrast-enhanced, portal-venous phase CT of the abdomen. Radiomic features were extracted using the PyRadiomics extension for 3D Slicer. Following elastic net regularisation, seven of 1,132 extracted radiomic features were selected to build a radiomic signature. This was combined with patient demographics to create a predictive nomogram. The calibration curves in both the training and validation cohorts were assessed using a Hosmer-Lemeshow test. RESULTS: The radiomic signature alone yielded an area under the curve of 91.7% in the training cohort (n=93) and 87.1% in the validation cohort (n=48). The predictive nomogram, which combined age, a previous history of malignancy, and the radiomic signature, had an AUC of 97.2% in the training cohort and 90.4% in the validation cohort. CONCLUSION: The present nomogram has the potential to differentiate between a lipid-poor adrenal adenoma and adrenal metastasis on portal-venous CT.


Assuntos
Adenoma , Neoplasias das Glândulas Suprarrenais , Abdome/patologia , Adenoma/diagnóstico por imagem , Adenoma/patologia , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/secundário , Idoso , Feminino , Humanos , Lipídeos , Masculino , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
2.
Clin Radiol ; 77(7): 514-521, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35487779

RESUMO

AIM: To evaluate the change in diagnosis rates, disease severity at presentation, and treatment of acute appendicitis and diverticulitis during the COVID-19 shutdown. MATERIALS AND METHODS: Following institutional review board approval, 6,002 CT examinations performed at five hospitals for suspected acute appendicitis and/or diverticulitis over the 12 weeks preceding and following the shutdown were reviewed retrospectively. Semi-automated language analysis (SALA) of the report classified 3,676 CT examinations as negative. Images of the remaining 2,326 CT examinations were reviewed manually and classified as positive or negative. Positive cases were graded as non-perforated; perforated, contained; and perforated, free. RESULTS: CT examinations performed for suspected appendicitis and/or diverticulitis decreased from 3,558 to 2,200 following the shutdown. The rates of positive diagnoses before and after shutdown were 4% (144) and 4% (100) for appendicitis and 8% (284) and 7% (159) for diverticulitis (p>0.2 for both). For positive CT examinations, the rates of perforation, hospitalisation, surgery, and catheter drainage changed by -2%, -3%, -2%, and -3% for appendicitis (n=244, p>0.3 for all) and +6% (p=0.2) +9% (p=0.06), +4% (p=0.01) and +1% (p=0.6) for diverticulitis (n=443). CONCLUSION: CT examinations performed for suspected appendicitis or diverticulitis declined after the shutdown, likely reflecting patients leaving urban centres and altered triage of non-COVID-19 patients. The diagnosis rates, disease severity at presentation, and treatment approach otherwise remained mostly unchanged.


Assuntos
Apendicite , COVID-19 , Diverticulite , Doença Aguda , Apendicite/diagnóstico por imagem , Apendicite/cirurgia , COVID-19/diagnóstico por imagem , Diverticulite/diagnóstico por imagem , Diverticulite/cirurgia , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
3.
Clin Radiol ; 76(2): 154.e1-154.e9, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32896425

RESUMO

Oncology has progressed into an era of personalised medicine, whereby the therapeutic regimen is tailored to the molecular profile of the patient's cancer. Determining personalised therapeutic options is achieved by using tumour genomics and proteomics to identify the specific molecular targets against which candidate drugs can interact. Several dozen targeted drugs, many for multiple cancer types are already widely in clinical use. Molecular profiling of tumours is contingent on high-quality biopsy specimens and the most common method of tissue sampling is image-guided biopsy. Thus, for radiologists performing these biopsies, the paradigm has now shifted away from obtaining specimens simply for histopathological diagnosis to acquiring larger amounts of viable tumour cells for DNA, RNA, or protein analysis. These developments have highlighted the central role now played by radiologists in the delivery of personalised cancer care. This review describes the principles of molecular profiling assays and biopsy techniques for optimising yield, and describes a scoring system to assist in patient selection for percutaneous biopsy.


Assuntos
Diagnóstico por Imagem/métodos , Genômica/métodos , Neoplasias/genética , Neoplasias/patologia , Medicina de Precisão/métodos , Biomarcadores Tumorais , Humanos , Biópsia Guiada por Imagem , Neoplasias/diagnóstico por imagem
4.
Nanotechnology ; 31(9): 092002, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31726444

RESUMO

Printed electronics is simultaneously one of the most intensely studied emerging research areas in science and technology and one of the fastest growing commercial markets in the world today. For the past decade the potential for organic electronic (OE) materials to revolutionize this printed electronics space has been widely promoted. Such conviction in the potential of these carbon-based semiconducting materials arises from their ability to be dissolved in solution, and thus the exciting possibility of simply printing a range of multifunctional devices onto flexible substrates at high speeds for very low cost using standard roll-to-roll printing techniques. However, the transition from promising laboratory innovations to large scale prototypes requires precise control of nanoscale material and device structure across large areas during printing fabrication. Maintaining this nanoscale material control during printing presents a significant new challenge that demands the coupling of OE materials and devices with clever nanoscience fabrication approaches that are adapted to the limited thermodynamic levers available. In this review we present an update on the strategies and capabilities that are required in order to manipulate the nanoscale structure of large area printed organic photovoltaic (OPV), transistor and bioelectronics devices in order to control their device functionality. This discussion covers a range of efforts to manipulate the electroactive ink materials and their nanostructured assembly into devices, and also device processing strategies to tune the nanoscale material properties and assembly routes through printing fabrication. The review finishes by highlighting progress in printed OE devices that provide a feedback loop between laboratory nanoscience innovations and their feasibility in adapting to large scale printing fabrication. The ability to control material properties on the nanoscale whilst simultaneously printing functional devices on the square metre scale is prompting innovative developments in the targeted nanoscience required for OPV, transistor and biofunctional devices.

5.
Phys Chem Chem Phys ; 21(10): 5705-5715, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30801074

RESUMO

A modified synthesis method for aqueous nanoparticle printing inks, based upon vacuum-assisted solvent removal, is reported. Poly(3-hexylthiophene):phenyl C61 butyric acid methyl ester nanoparticle inks were prepared via this modified miniemulsion method, leading to both an improvement in photoactive layer morphology and a substantial reduction in the ink fabrication time. A combination of UV-visible spectroscopy, photoluminescence spectroscopy and scanning transmission X-ray microscopy measurements revealed a nanoparticle morphology comprising highly intermixed donor-acceptor domains. Consistent with these measurements, dynamic mechanical thermal analysis of the nanoparticles showed a glass transition temperature (Tg) of 104 °C, rather than a pure polymer phase or pure fullerene phase Tg. Together the spectroscopy, microscopy and thermomechanical data indicate that rapid solvent removal generates a more blended nanoparticle morphology. As such, this study highlights a new experimental lever for optimising nanostructure in the photoactive layer of nanoparticulate organic photovoltaic devices by enabling highly intermixed donor-acceptor architectures to be built from customised nanoparticulate inks.

6.
Clin Radiol ; 74(3): 187-195, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30638605

RESUMO

AIM: To determine if pure ground-glass opacities (GGOs) and the subgroup of ground-glass nodules (GGNs) typically demonstrate higher 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG) uptake at positron-emission tomography (PET) when benign than when malignant. MATERIALS AND METHODS: Informed consent was waived for this institutional review board (IRB)-approved, Health Insurance Portability and Accountability Act (HIPAA) compliant, retrospective study. A review of all 1,864 combined PET/computed tomography (CT) examinations performed in 2011 on a single system to identify pure GGOs with mean diameter ≥1 cm yielded 166 GGOs. Two blinded subspecialty-trained thoracic radiologists independently assessed GGO size, morphology, attenuation, and location on CT. A blinded nuclear radiologist procured the SUVmax for each GGO. Final diagnosis of malignancy (n=21) was made based on histopathology or upon increased size and attenuation; a final diagnosis of benignity (n=106) was made if GGO resolved, was new within 3 months, evolved in a manner consistent with pulmonary fibrosis, or was stable for ≥60 months; 29 were indeterminate and were excluded, along with 10 cases with unreliable SUVmax measurements, yielding 127 GGOs, of which 68 were GGNs, in 76 patients. RESULTS: The SUVmax was significantly higher in benign than malignant GGOs (p=0.0017) and in the GGN subgroup (p=0.03). A threshold SUVmax >1.5 for GGOs, including GGNs, assured benignity in this cohort. CONCLUSION: Benign GGOs and the benign GGN subgroup demonstrated significantly higher FDG uptake at PET than malignant GGOs/GGNs. Awareness of this finding may prevent misinterpretation of highly 18FDG-avid pure GGOs/GGNs as definitively malignant, which could lead to unnecessary thoracic surgery and its associated risks.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Nódulo Pulmonar Solitário/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Fluordesoxiglucose F18 , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Nódulo Pulmonar Solitário/patologia
7.
Clin Radiol ; 74(9): 692-696, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31202569

RESUMO

AIM: To assess the ability of artificial neural networks (ANNs) to predict the likelihood of malignancy of pure ground-glass opacities (GGOs), using observations from computed tomography (CT) and 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET) images and relevant clinical information. MATERIALS AND METHODS: One hundred and twenty-five cases of pure GGOs described in a previous article were used to train and evaluate the performance of an ANN to predict the likelihood of malignancy in each of the GGOs. Eighty-five cases selected randomly were used for training the network and the remaining 40 cases for testing. The ANN was constructed from the image data and basic clinical information. The predictions of the ANN were compared with blinded expert estimates of the likelihood of malignancy. RESULTS: The ANN showed excellent predictive value in estimating the likelihood of malignancy (AUC = 0.98±0.02). Employing the optimal cut-off point from the receiver operating characteristic (ROC) curve, the ANN correctly identified 11/11 malignant lesions (sensitivity 100%) and 27/29 benign lesions (specificity 93.1%). The expert readers found 23 lesions indeterminate and correctly identified 17 lesions as benign. CONCLUSION: ANNs have potential to improve diagnostic certainty in the classification of pure GGOs, based upon their CT appearance, intensity of FDG uptake, and relevant clinical information, and may therefore, be useful to help direct clinical and imaging follow-up.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Redes Neurais de Computação , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Diagnóstico Diferencial , Feminino , Fluordesoxiglucose F18 , Humanos , Neoplasias Pulmonares/patologia , Masculino , Valor Preditivo dos Testes , Interpretação de Imagem Radiográfica Assistida por Computador , Compostos Radiofarmacêuticos , Estudos Retrospectivos
8.
Nano Lett ; 15(7): 4282-8, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26061698

RESUMO

The performance of battery electrode materials is strongly affected by inefficiencies in utilization kinetics and cycle life as well as size effects. Observations of phase transformations in these materials with high chemical and spatial resolution can elucidate the relationship between chemical processes and mechanical degradation. Soft X-ray ptychographic microscopy combined with X-ray absorption spectroscopy and electron microscopy creates a powerful suite of tools that we use to assess the chemical and morphological changes in lithium iron phosphate (LiFePO4) micro- and nanocrystals that occur upon delithiation. All sizes of partly delithiated crystals were found to contain two phases with a complex correlation between crystallographic orientation and phase distribution. However, the lattice mismatch between LiFePO4 and FePO4 led to severe fracturing on microcrystals, whereas no mechanical damage was observed in nanoplates, indicating that mechanics are a principal driver in the outstanding electrode performance of LiFePO4 nanoparticles. These results demonstrate the importance of engineering the active electrode material in next generation electrical energy storage systems, which will achieve theoretical limits of energy density and extended stability. This work establishes soft X-ray ptychographic chemical imaging as an essential tool to build comprehensive relationships between mechanics and chemistry that guide this engineering design.

9.
Nat Mater ; 13(12): 1149-56, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25218062

RESUMO

Many battery electrodes contain ensembles of nanoparticles that phase-separate on (de)intercalation. In such electrodes, the fraction of actively intercalating particles directly impacts cycle life: a vanishing population concentrates the current in a small number of particles, leading to current hotspots. Reports of the active particle population in the phase-separating electrode lithium iron phosphate (LiFePO4; LFP) vary widely, ranging from near 0% (particle-by-particle) to 100% (concurrent intercalation). Using synchrotron-based X-ray microscopy, we probed the individual state-of-charge for over 3,000 LFP particles. We observed that the active population depends strongly on the cycling current, exhibiting particle-by-particle-like behaviour at low rates and increasingly concurrent behaviour at high rates, consistent with our phase-field porous electrode simulations. Contrary to intuition, the current density, or current per active internal surface area, is nearly invariant with the global electrode cycling rate. Rather, the electrode accommodates higher current by increasing the active particle population. This behaviour results from thermodynamic transformation barriers in LFP, and such a phenomenon probably extends to other phase-separating battery materials. We propose that modifying the transformation barrier and exchange current density can increase the active population and thus the current homogeneity. This could introduce new paradigms to enhance the cycle life of phase-separating battery electrodes.

10.
Phys Rev Lett ; 114(1): 013002, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25615465

RESUMO

Single, double, and triple ionization of C(1+) ions by single photons is investigated in the energy range of 286-326 eV, i.e., in the range from the lowest-energy K-vacancy resonances to well beyond the K-shell ionization threshold. Clear signatures of C(1+)(1s2s(2)2p(2) (2)D,(2)P) resonances are found in the triple-ionization channel. The only possible mechanism producing C(4+)(1s(2)) via these resonances is direct triple-Auger decay, i.e., a four-electron process with simultaneous emission of three electrons.

11.
Clin Radiol ; 69(12): 1280-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25240564

RESUMO

AIM: To assess the short and medium-term efficacy and safety of a novel, minimally invasive therapeutic option combining automated percutaneous lumbar discectomy, intradiscal ozone injection, and caudal epidural: ozone-augmented percutaneous discectomy (OPLD). MATERIALS AND METHODS: One hundred and forty-seven patients with a clinical and radiological diagnosis of discogenic sciatica who were refractory to initial therapy were included. Fifty patients underwent OPLD whilst 97 underwent a further caudal epidural. Outcomes were evaluated using McNab's score, improvement in visual analogue score (VAS) pain score, and requirement for further intervention. Follow-up occurred at 1 and 6 months, and comparison was made between groups. RESULTS: OPLD achieved successful outcomes in almost three-quarters of patients in the short and medium term. OPLD achieved superior outcomes at 1 and 6 months compared to caudal epidural. There was a reduced requirement for further intervention in the OPLD group. No significant complications occurred in either group. DISCUSSION: OPLD is a safe and effective treatment for patients with refractory discogenic sciatica in the short and medium term. OPLD has the potential to offer an alternative second-line minimally invasive treatment option that could reduce the requirement for surgery in this patient cohort.


Assuntos
Discotomia Percutânea/métodos , Deslocamento do Disco Intervertebral/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Ozônio/administração & dosagem , Ciática/cirurgia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Injeções Espinhais , Deslocamento do Disco Intervertebral/complicações , Deslocamento do Disco Intervertebral/patologia , Vértebras Lombares/patologia , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Ciática/etiologia , Ciática/patologia , Resultado do Tratamento
12.
Proc Natl Acad Sci U S A ; 108(48): 19171-6, 2011 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-21464292

RESUMO

Multidimensional solid-state NMR spectroscopy is used to refine the identification and abundance determination of functional groups in insoluble organic matter (IOM) isolated from a carbonaceous chondrite (Murchison, CM2). It is shown that IOM is composed primarily of highly substituted single ring aromatics, substituted furan/pyran moieties, highly branched oxygenated aliphatics, and carbonyl groups. A pathway for producing an IOM-like molecular structure through formaldehyde polymerization is proposed and tested experimentally. Solid-state (13)C NMR analysis of aqueously altered formaldehyde polymer reveals considerable similarity with chondritic IOM. Carbon X-ray absorption near edge structure spectroscopy of formaldehyde polymer reveals the presence of similar functional groups across certain Comet 81P/Wild 2 organic solids, interplanetary dust particles, and primitive IOM. Variation in functional group concentration amongst these extraterrestrial materials is understood to be a result of various degrees of processing in the parent bodies, in space, during atmospheric entry, etc. These results support the hypothesis that chondritic IOM and cometary refractory organic solids are related chemically and likely were derived from formaldehyde polymer. The fine-scale morphology of formaldehyde polymer produced in the experiment reveals abundant nanospherules that are similar in size and shape to organic nanoglobules that are ubiquitous in primitive chondrites.


Assuntos
Meio Ambiente Extraterreno/química , Formaldeído/química , Espectroscopia de Ressonância Magnética/métodos , Meteoroides , Nanoestruturas/química , Compostos Orgânicos/análise , Microscopia Eletrônica de Varredura , Modelos Químicos , Estrutura Molecular , Polimerização
13.
Proc Natl Acad Sci U S A ; 108(21): 8550-3, 2011 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-21555550

RESUMO

Aerogel materials have myriad scientific and technological applications due to their large intrinsic surface areas and ultralow densities. However, creating a nanodiamond aerogel matrix has remained an outstanding and intriguing challenge. Here we report the high-pressure, high-temperature synthesis of a diamond aerogel from an amorphous carbon aerogel precursor using a laser-heated diamond anvil cell. Neon is used as a chemically inert, near-hydrostatic pressure medium that prevents collapse of the aerogel under pressure by conformally filling the aerogel's void volume. Electron and X-ray spectromicroscopy confirm the aerogel morphology and composition of the nanodiamond matrix. Time-resolved photoluminescence measurements of recovered material reveal the formation of both nitrogen- and silicon- vacancy point-defects, suggesting a broad range of applications for this nanocrystalline diamond aerogel.

14.
J Am Chem Soc ; 135(8): 3224-36, 2013 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-23343247

RESUMO

Monometallic niobium arene complexes [Nb(BDI)(N(t)Bu)(R-C(6)H(5))] (2a: R = H and 2b: R = Me, BDI = N,N'-diisopropylbenzene-ß-diketiminate) were synthesized and found to undergo slow conversion into the diniobium inverted arene sandwich complexes [[(BDI)Nb(N(t)Bu)](2)(µ-RC(6)H(5))] (7a: R = H and 7b: R = Me) in solution. The kinetics of this reaction were followed by (1)H NMR spectroscopy and are in agreement with a dissociative mechanism. Compounds 7a-b showed a lack of reactivity toward small molecules, even at elevated temperatures, which is unusual in the chemistry of inverted sandwich complexes. However, protonation of the BDI ligands occurred readily on treatment with [H(OEt(2))][B(C(6)F(5))(4)], resulting in the monoprotonated cationic inverted sandwich complex 8 [[(BDI(#))Nb(N(t)Bu)][(BDI)Nb(N(t)Bu)](µ-C(6)H(5))][B(C(6)F(5))(4)] and the dicationic complex 9 [[(BDI(#))Nb(N(t)Bu)](2)(µ-RC(6)H(5))][B(C(6)F(5))(4)](2) (BDI(#) = (ArNC(Me))(2)CH(2)). NMR, UV-vis, and X-ray absorption near-edge structure (XANES) spectroscopies were used to characterize this unique series of diamagnetic molecules as a means of determining how best to describe the Nb-arene interactions. The X-ray crystal structures, UV-vis spectra, arene (1)H NMR chemical shifts, and large J(CH) coupling constants provide evidence for donation of electron density from the Nb d-orbitals into the antibonding π system of the arene ligands. However, Nb L(3,2)-edge XANES spectra and the lack of sp(3) hybridization of the arene carbons indicate that the Nb → arene donation is not accompanied by an increase in Nb formal oxidation state and suggests that 4d(2) electronic configurations are appropriate to describe the Nb atoms in all four complexes.

15.
Nanotechnology ; 22(26): 265710, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21586810

RESUMO

Water-processable nanoparticle dispersions of semiconducting polymers offer an attractive approach to the fabrication of organic electronic devices since they offer: (1) control of nanoscale morphology and (2) environmentally friendly fabrication. Although the nature of phase segregation in these polymer nanoparticles is critical to device performance, to date there have been no techniques available to directly determine their intra-particle structure, which consequently has been poorly understood. Here, we present scanning transmission x-ray microscopy (STXM) compositional maps for nanoparticles fabricated from poly(9,9-dioctyl-fluorene-2,7-diyl-co-bis-N, N'-(4-butylphenyl)-bis-N, N'-phenyl-1,4-phenylenedi-amine) (PFB) and poly(9,9-dioctylfluorene-2,7-diyl-co-benzothiadiazole) (F8BT) 1:1 blend mixtures. The images show distinct phase segregation within the nanoparticles. The compositional data reveals that, within these nanoparticles, PFB and F8BT segregate into a core-shell morphology, with an F8BT-rich core and a PFB-rich shell. Structural modelling demonstrates that the STXM technique is capable of quantifying morphological features on a sub-10 nm length scale; below the spot size of the incident focused x-ray beam. These results have important implications for the development of water-based 'solar paints' fabricated from microemulsions of semiconducting polymers.

16.
Abdom Radiol (NY) ; 46(3): 1171-1178, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32945923

RESUMO

PURPOSE: To determine the sensitivity, specificity, and complication rate of percutaneous adrenal biopsy in patients with known or suspected lung cancer. METHODS: This study was approved by the Institutional Review Board at our institution as a retrospective analysis; therefore, the need for informed consent was waived. All percutaneous adrenal biopsies performed between April 1993 and May 2019 were reviewed. 357 of 582 biopsies were performed on 343 patients with known or suspected lung cancer (M:F 164:179; mean age 66 years). The biopsy results were classified into malignant, benign, or non-diagnostic. The final diagnosis was established by pathology (biopsy and/or surgical resection) or imaging follow-up on CT for at least 12 months following the biopsy. Patients with less than 12 months follow-up were excluded (n = 44). Complications were recorded. RESULTS: The final diagnosis was metastatic lung cancer in 235 cases (77.8%), metastasis from an extrapulmonary primary in 2 cases (0.7%), pheochromocytoma in 2 cases (0.7%), and benign lesions in 63 cases (20.9%). Percutaneous adrenal gland biopsy had a sensitivity of 97% and specificity of 100% for lung cancer metastases. The non-diagnostic rate was 0.6%. Larger lesions were more likely to be malignant (p = 0.0000) and to be correctly classified as a lung metastasis (p = 0.025). The incidence of minor complications was 1.1%. There were no major complications. CONCLUSION: Over 20% of adrenal lesions in patients with known or suspected lung cancer were not related to lung cancer. Percutaneous adrenal gland biopsy is a safe procedure, with high sensitivity and specificity for lung cancer metastases.


Assuntos
Neoplasias das Glândulas Suprarrenais , Neoplasias Pulmonares , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Idoso , Humanos , Biópsia Guiada por Imagem , Neoplasias Pulmonares/diagnóstico por imagem , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
17.
Chem Commun (Camb) ; 57(40): 4954-4957, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-33876158

RESUMO

We report the synthesis of four homoleptic thorium(iv) amidate complexes as single-source molecular precursors for thorium dioxide. Each can be sublimed at atmospheric pressure, with the substituents on the amidate ligands significantly impacting their volatility and thermal stability. These complexes decompose via alkene elimination to give ThO2 without need for a secondary oxygen source. ThO2 samples formed from pyrolysis of C-alkyl amidates were found to have higher purity and crystallinity than ThO2 samples formed from C-aryl amidates.

18.
Phys Rev Lett ; 105(21): 213001, 2010 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-21231297

RESUMO

Experimental evidence is presented for confinement resonances associated with photoabsorption by a Xe atom in a C60 cage. The giant 4d resonance in photoionization of Xe is predicted to be redistributed into four components due to multipath interference of photoelectron waves reflected by the cage. The measurements were made in the photon energy range 60-150 eV by merging a beam of synchrotron radiation with a mass/charge selected Xe@C60+ ion beam. The phenomenon was observed in the Xe@C(58)(3+) product ion channel. [corrected]

19.
Diabetes Obes Metab ; 11(12): 1153-62, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19930005

RESUMO

AIM: The Helping Evaluate Exenatide in overweight patients with diabetes compared with Long-Acting insulin (HEELA) study was designed to examine whether the glucagon-like peptide-1 (GLP-1) receptor agonist, exenatide, could improve HbA1c (< or =7.4%) with minimal weight gain (< or =1 kg) compared with insulin glargine. METHODS: Patients [body mass index (BMI) >27 kg/m(2)] with elevated cardiovascular risk and type 2 diabetes inadequately controlled on two or three oral antidiabetes drugs (OADs) were randomized to add-on exenatide 5-10 microg b.i.d. (n = 118) or insulin glargine o.d. (titrated to target fasting plasma glucose < or =5.6 mmol/l; n = 117) for 26 weeks. RESULTS: The study population had baseline mean (s.d.) age of 56.5 (9.1) years and BMI of 34.1 (5.3) kg/m(2), and 58.5% of patients were taking two OADs. Mean baseline HbA1c was 8.65 (0.68)% in the exenatide group and 8.48 (0.66)% in the insulin glargine group. The proportions of patients achieving the composite endpoint of HbA1c < or =7.4% with weight gain < or =1 kg were 53.4% for the exenatide group and 19.8% for the insulin glargine group (p < 0.001 for exenatide vs. insulin glargine). Exenatide and insulin glargine did not demonstrate a significant difference in HbA1c improvements [least square (LS) mean [s.e.m.]: -1.25 [0.09]% and -1.26 [0.09]% respectively; p = 0.924], but had divergent effects on body weight (-2.73 [0.31] vs. +2.98 [0.31] kg respectively, p < 0.001) after 26 weeks. There were more treatment-related adverse events with exenatide but a lower incidence of nocturnal hypoglycaemia, with no differences in overall or severe hypoglycaemia. CONCLUSIONS: Additional treatment with exenatide resulted in significantly more overweight and obese patients with an elevated cardiovascular risk and type 2 diabetes achieving better glycaemic control with minimal weight gain compared with insulin glargine.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Insulina de Ação Prolongada/uso terapêutico , Peptídeos/uso terapêutico , Peçonhas/uso terapêutico , Aumento de Peso/efeitos dos fármacos , Exenatida , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Reino Unido
20.
Clin Exp Rheumatol ; 27(4): 649-50, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19772799

RESUMO

INTRODUCTION: I n order to assess the value of using the methotrexate information booklet, we conducted a single blind prospective controlled trial of the patients attending two rheumatology services. METHODS: The active-arm (n=40) used the MTX information booklet for the patients' education and the control-arm (n=38) did not. Patients' interviews were conducted over a 6-month period using an MTX-questionnaire. RESULTS: The entire active-arm patients (100%) were taking folic-acid and 32 (80%) knew the reason why they were taking folic-acid vs. [30 (79%) and 10 (26%) in the control-arm]. In the active-arm 35 (88%) knew the reason for their monthly blood tests vs. 18 (47%) in the control-arm. The entire active-arm was aware of the need for contraception use and MTX-side effects vs. 23 (60%) and 15 (40%) in the control-arm respectively. CONCLUSIONS: The use of the MTX information booklet in our cohort improved their understanding of the treatment.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Metotrexato/uso terapêutico , Educação de Pacientes como Assunto/métodos , Materiais de Ensino , Antirreumáticos/efeitos adversos , Artrite Reumatoide/psicologia , Ensaios Clínicos como Assunto , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Entrevistas como Assunto , Masculino , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Método Simples-Cego
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