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1.
Cancer Imaging ; 23(1): 92, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770958

RESUMO

BACKGROUND: Histopathology is the reference standard for diagnosing liver metastases of neuroendocrine tumors (NETs). Somatostatin receptor-positron emission tomography / computed tomography (SSR-PET/CT) has emerged as a promising non-invasive imaging modality for staging NETs. We aimed to assess the diagnostic accuracy of SSR-PET/CT in the identification of liver metastases in patients with proven NETs compared to histopathology. METHODS: Histopathologic reports of 139 resected or biopsied liver lesions of patients with known NET were correlated with matching SSR-PET/CTs and the positive/negative predictive value (PPV/NPV), sensitivity, specificity, and diagnostic accuracy of SSR-PET/CT were evaluated. PET/CT reading was performed by one expert reader blinded to histopathology and clinical data. RESULTS: 133 of 139 (95.7%) liver lesions showed malignant SSR-uptake in PET/CT while initial histopathology reported on 'liver metastases of NET´ in 127 (91.4%) cases, giving a PPV of 91.0%. Re-biopsy of the initially histopathologically negative lesions (reference standard) nevertheless diagnosed 'liver metastases of NET' in 6 cases, improving the PPV of PET/CT to 95.5%. Reasons for initial false-negative histopathology were inadequate sampling in the sense of non-target biopsies. The 6 (4.3%) SSR-negative lesions were all G2 NETs with a Ki-67 between 2-15%. CONCLUSION: SSR-PET/CT is a highly accurate imaging modality for the diagnosis of liver metastases in patients with proven NETs. However, we found that due to the well-known tumor heterogeneity of NETs, specifically in G2 NETs approximately 4-5% are SSR-negative and may require additional imaging with [18F]FDG PET/CT.


Assuntos
Neoplasias Hepáticas , Tumores Neuroendócrinos , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/patologia , Receptores de Somatostatina , Tomografia por Emissão de Pósitrons/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Fluordesoxiglucose F18 , Sensibilidade e Especificidade , Compostos Radiofarmacêuticos
2.
J Cancer Res Clin Oncol ; 149(11): 8225-8234, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37062035

RESUMO

PURPOSE: For patients with cancer of unknown primary (CUP), treatment options are limited. Precision oncology, the interplay of comprehensive genomic profiling (CGP) and targeted therapies, aims to offer additional treatment options to patients with advanced and hard-to-treat cancers. We aimed to highlight the use of a molecular tumor board (MTB) in the therapeutic management of CUP patients. METHODS: In this single-center observational study, CUP patients, presented to the MTB of the Comprehensive Cancer Center Munich LMU, a tertiary care center, were analyzed retrospectively. Descriptive statistics were applied to describe relevant findings. RESULTS: Between June 2016 and February 2022, 61 patients with unfavorable CUP were presented to the MTB, detected clinically relevant variants in 74% (45/61) of patients, of which 64% (29/45) led to therapeutic recommendation. In four out of 29 patients (14%), the treatment recommendations were implemented, unfortunately without resulting in clinical benefit. Reasons for not following the therapeutic recommendation were mainly caused by the physicians' choice of another therapy (9/25, 36%), especially in the context of worsening of general condition, lost to follow-up (7/25, 28%) and death (6/25, 24%). CONCLUSION: CGP and subsequent presentation to a molecular tumor board led to a high rate of therapeutic recommendations in patients with CUP. Recommendations were only implemented at a low rate; however, late GCP diagnostic and, respectively, MTB referral were found more frequent for the patients with implemented treatment. This contrast underscores the need for early implementation of CGP into the management of CUP patients.


Assuntos
Neoplasias Primárias Desconhecidas , Humanos , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/genética , Neoplasias Primárias Desconhecidas/terapia , Estudos Retrospectivos , Medicina de Precisão/métodos , Oncologia
3.
AJNR Am J Neuroradiol ; 43(11): 1597-1602, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36229165

RESUMO

BACKGROUND AND PURPOSE: Radiographic shunt series are still the imaging technique of choice for radiologic evaluation of VP-shunt complications. Radiographic shunt series are associated with high radiation exposure and have a low diagnostic performance. Our aim was to investigate the diagnostic performance of whole-body ultra-low-dose CT for detecting mechanical ventriculoperitoneal shunt complications. MATERIALS AND METHODS: This retrospective study included 186 patients (mean age, 54.8 years) who underwent whole-body ultra-low-dose CT (100 kV[peak]; reference, 10 mAs). Two radiologists reviewed the images for the presence of ventriculoperitoneal shunt complications, image quality, and diagnostic confidence. On a 5-point Likert scale, readers scored image quality and diagnostic confidence (1 = very low, 5 = very high). Sensitivity, specificity, positive predictive value, and negative predictive value were calculated. Radiation dose estimation of whole-body ultra-low-dose CT was calculated and compared with the radiation dose of a radiographic shunt series. RESULTS: 34 patients positive for VP-shunt complications were correctly identified on whole-body ultra-low-dose CT by both readers. No false-positive or -negative cases were recorded by any of the readers, yielding a sensitivity of 100% (95% CI, 87.3%-100%), a specificity of 100% (95% CI, 96.9%-100%), and perfect agreement (κ = 1). Positive and negative predictive values were high at 100%. Shunt-specific image quality and diagnostic confidence were very high (median score, 5; range, 5-5). Interobserver agreement was substantial for image quality (κ = 0.73) and diagnostic confidence (κ = 0.78). The mean radiation dose of whole-body ultra-low-dose CT was significantly lower than the radiation dose of a conventional radiographic shunt series (0.67 [SD, 0.4] mSv versus 1.57 [SD, 0.6] mSv; 95% CI, 0.79-1.0 mSv; P < .001). CONCLUSIONS: Whole-body ultra-low-dose CT allows detection of ventriculoperitoneal shunt complications with excellent diagnostic accuracy and diagnostic confidence. With concomitant radiation dose reduction on contemporary CT scanners, whole-body ultra-low-dose CT should be considered an alternative to the radiographic shunt series.


Assuntos
Exposição à Radiação , Derivação Ventriculoperitoneal , Humanos , Pessoa de Meia-Idade , Derivação Ventriculoperitoneal/efeitos adversos , Estudos Retrospectivos , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Sensibilidade e Especificidade
5.
Eur Radiol ; 31(3): 1443-1450, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32885295

RESUMO

OBJECTIVES: The aim of this retrospective study was to determine cost-effectiveness of stress myocardial CT perfusion (CTP), coronary CT angiography (CTA), and the combination of both in suspected obstructive coronary artery disease (CAD) or in-stent restenosis (ISR) in patients with previous coronary stent implantation. METHODS: A decision model based on Markov simulations estimated lifetime costs and quality-adjusted life years (QALYs) associated with CTA, CTP, and CTA + CTP. Model input parameters were obtained from published literature. Probabilistic sensitivity analysis was performed to evaluate overall model uncertainty. A single-variable deterministic sensitivity analysis evaluated the sensitivity of the results to plausible variations in model inputs. Cost-effectiveness was assessed based on a cost-effectiveness threshold of $100,000 per QALY. RESULTS: In the base-case scenario with willingness to pay of $100,000 per QALY, CTA resulted in total costs of $47,013.87 and an expected effectiveness of 6.84 QALYs, whereas CTP resulted in total costs of $46,758.83 with 6.93 QALYs. CTA + CTP reached costs of $47,455.63 with 6.85 QALYs. Therefore, strategies CTA and CTA + CTP were dominated by CTP in the base-case scenario. Deterministic sensitivity analysis demonstrated robustness of the model to variations of diagnostic efficacy parameters and costs in a broad range. CTP was cost-effective in the majority of iterations in the probabilistic sensitivity analysis as compared with CTA. CONCLUSIONS: CTP is cost-effective for the detection of obstructive CAD or ISR in patients with previous stenting and therefore should be considered a feasible approach in daily clinical practice. KEY POINTS: • CTP provides added diagnostic value in patients with previous coronary stents. • CTP is a cost-effective method for the detection of obstructive CAD or ISR in patients with previous stenting.


Assuntos
Doença da Artéria Coronariana , Reestenose Coronária , Imagem de Perfusão do Miocárdio , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Reestenose Coronária/diagnóstico por imagem , Análise Custo-Benefício , Humanos , Valor Preditivo dos Testes , Estudos Prospectivos , Estudos Retrospectivos , Stents , Tomografia Computadorizada por Raios X
6.
Eur J Nucl Med Mol Imaging ; 48(6): 2031-2037, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33369689

RESUMO

INTRODUCTION: Tyrosine kinase (TKI) and checkpoint inhibitors (CI) prolonged overall survival in metastatic renal cell carcinoma (mRCC). Early prediction of treatment response is highly desirable for the individualization of patient management and improvement of therapeutic outcome; however, serum biochemistry is unable to predict therapeutic efficacy. Therefore, we compared 18F-PSMA-1007 PET imaging for response assessment in mRCC patients undergoing TKI or CI therapy compared to CT-based response assessment as the current imaging reference standard. METHODS: 18F-PSMA-1007 PET/CT was performed in mRCC patients prior to initiation of systemic treatment and 8 weeks after therapy initiation. Treatment response was evaluated separately on 18F-PSMA-PET and CT. Changes on PSMA-PET (SUVmean) were assessed on a per patient basis using a modified PERCIST scoring system. Complete response (CRPET) was defined as absence of any uptake in all target lesions on posttreatment PET. Partial response (PRPET) was defined as decrease in summed SUVmean of > 30%. The appearance of new, PET-positive lesions or an increase in summed SUVmean of > 30% was defined as progressive disease (PDPET). A change in summed SUVmean of ± 30% defined stable disease (SDPET). RECIST 1.1 criteria were used for response assessment on CT. Results of radiographic response assessment on PSMA-PET and CT were compared. RESULTS: Overall, 11 mRCC patients undergoing systemic treatment were included. At baseline PSMA-PET1, all mRCC patients showed at least one PSMA-avid lesion. On follow-up PET2, 3 patients showed CRPET, 3 PRPET, 4 SDPET, and 1 PDPET. According to RECIST 1.1, 1 patient showed PRCT, 9 SDCT, and 1 PDCT. Overall, concordant classifications were found in only 2 cases (2 SDCT + PET). Patients with CRPET on PET were classified as 3 SDCT on CT using RECIST 1.1. By contrast, the patient classified as PRCT on CT showed PSMA uptake without major changes during therapy (SDPET). However, among 9 patients with SDCT on CT, 3 were classified as CRPET, 3 as PRPET, 1 as PDPET, and only 2 as SDPET on PSMA-PET. CONCLUSION: On PSMA-PET, heterogeneous courses were observed during systemic treatment in mRCC patients with highly diverging results compared to RECIST 1.1. In the light of missing biomarkers for early response assessment, PSMA-PET might allow more precise response assessment to systemic treatment, especially in patients classified as SD on CT.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/tratamento farmacológico , Radioisótopos de Flúor , Humanos , Inibidores de Checkpoint Imunológico , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/tratamento farmacológico , Niacinamida/análogos & derivados , Oligopeptídeos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Inibidores de Proteínas Quinases , Proteínas Tirosina Quinases , Compostos Radiofarmacêuticos
7.
Radiat Oncol ; 15(1): 88, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317029

RESUMO

Radiotherapy and radiation oncology play a key role in the clinical management of patients suffering from oncological diseases. In clinical routine, anatomic imaging such as contrast-enhanced CT and MRI are widely available and are usually used to improve the target volume delineation for subsequent radiotherapy. Moreover, these modalities are also used for treatment monitoring after radiotherapy. However, some diagnostic questions cannot be sufficiently addressed by the mere use standard morphological imaging. Therefore, positron emission tomography (PET) imaging gains increasing clinical significance in the management of oncological patients undergoing radiotherapy, as PET allows the visualization and quantification of tumoral features on a molecular level beyond the mere morphological extent shown by conventional imaging, such as tumor metabolism or receptor expression. The tumor metabolism or receptor expression information derived from PET can be used as tool for visualization of tumor extent, for assessing response during and after therapy, for prediction of patterns of failure and for definition of the volume in need of dose-escalation. This review focuses on recent and current advances of PET imaging within the field of clinical radiotherapy / radiation oncology in several oncological entities (neuro-oncology, head & neck cancer, lung cancer, gastrointestinal tumors and prostate cancer) with particular emphasis on radiotherapy planning, response assessment after radiotherapy and prognostication.


Assuntos
Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Radioterapia (Especialidade) , Biomarcadores Tumorais/metabolismo , Progressão da Doença , Humanos , Imagem Molecular , Estadiamento de Neoplasias , Neoplasias/patologia , Neoplasias/radioterapia , Compostos Radiofarmacêuticos/uso terapêutico , Planejamento da Radioterapia Assistida por Computador
8.
Eur J Neurol ; 27(1): 168-174, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31349393

RESUMO

BACKGROUND AND PURPOSE: Acute ischemic stroke treatment with intravenous thrombolysis (IVT) is restricted to a time window of 4.5 h after known or presumed onset. Recently, magnetic resonance imaging-guided treatment decision-making in wake-up stroke (WUS) was shown to be effective. The aim of this study was to determine the safety and outcome of IVT in patients with a time window beyond 4.5 h selected by computed tomography perfusion (CTP) imaging. METHODS: We analyzed all consecutive patients last seen well beyond 4.5 h after stroke onset treated with IVT based on CTP between January 2015 and October 2018. CTP was visually assessed to estimate the mismatch between cerebral blood flow and cerebral blood volume maps. Early infarct signs were documented according to Alberta Stroke Program Early CT Score (ASPECTS). Safety data were obtained for mortality and symptomatic intracerebral hemorrhage (sICH). Follow-up was assessed with the modified Rankin Scale (mRS). RESULTS: A total of 70 patients fulfilled the inclusion criteria (mean age ± SD 77.6 ± 11.5 years, 50.0% female). Median National Institutes of Health Stroke Scale score on admission was 8.0 [interquartile range (IQR), 4-14]. The most frequent reasons for an extended time window were WUS (60.0%) and delayed hospital admission (27.1%). Median time from last seen well to IVT was 11.4 h. Median ASPECTS was 10 (IQR, 9-10) and CTP mismatch 90% (IQR, 80%-100%). A total of 24 patients (34.3%) underwent additional mechanical thrombectomy. sICH occurred in four patients (5.7%). At follow-up, 49.3% had an mRS score of 0-2 and 22.4% had an mRS score of 0-1. CONCLUSIONS: In patients presenting in an extended time window beyond 4.5 h, IVT treatment with decision-making based on CTP might be a safe procedure. Further evaluation in clinical trials is needed.


Assuntos
Fibrinolíticos/administração & dosagem , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Trombectomia/métodos , Administração Intravenosa , Idoso , Idoso de 80 Anos ou mais , Infarto Encefálico/diagnóstico por imagem , Circulação Cerebrovascular , Feminino , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão , Acidente Vascular Cerebral/cirurgia , Tempo para o Tratamento , Tomografia Computadorizada por Raios X , Resultado do Tratamento
9.
AJNR Am J Neuroradiol ; 41(1): 129-133, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31806593

RESUMO

BACKGROUND AND PURPOSE: The role of collateral imaging in selecting patients for endovascular thrombectomy beyond 6 hours from onset has not been established. To assess the comparative utility of collateral imaging using multiphase CTA in selecting late window patients for EVT. MATERIALS AND METHODS: We used data from a prospective multicenter observational study in which all patients underwent imaging with multiphase CT angiography as well as CTP. Two blinded reviewers evaluated patients' eligibility for endovascular thrombectomy using published collateral imaging (multiphase CTA) criteria compared with CTP using the selection criteria of the Clinical Mismatch in the Triage of Wake Up and Late Presenting Strokes Undergoing Neurointervention with Trevo (DAWN) and Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3 (DEFUSE-3) trials. CTP images were processed using automated commercial software. The outcomes of patients eligible for endovascular thrombectomy according to multiphase CTA, DAWN, or DEFUSE-3 criteria were compared using multivariable logistic regression modeling. Model characteristics were compared using the C-statistic for the receiver operating characteristic curve, the Akaike information criterion, and the Bayesian information criterion. RESULTS: Eighty-six patients presented beyond 6 hours from onset/last known well (median, 9.6 hours; interquartile range, 4.1 hours). Thirty-five patients (40.7%) received endovascular thrombectomy, of whom good functional outcome (90-day mRS, 0-2) was achieved in 16/35 (47%). Collateral-based imaging paradigms significantly modified the treatment effect of endovascular thrombectomy on 90-day mRS 0-2 (P interaction = .007). The multiphase CTA-based regression model best fit the data for the 90-day outcome (C-statistic, 0.86; 95% CI, 0.77-0.94) and was associated with the least information loss (Akaike information criterion, 95.7; Bayesian information criterion, 114.9) compared with CTP-based models. CONCLUSIONS: The collateral-based imaging paradigm using multiphase CTA compares well with CTP in selecting patients for endovascular thrombectomy in the late time window.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Seleção de Pacientes , Acidente Vascular Cerebral/diagnóstico por imagem , Tempo para o Tratamento , Tomografia Computadorizada por Raios X/métodos , Triagem/métodos , Idoso , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos
10.
Radiologe ; 59(11): 975-981, 2019 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-31338528

RESUMO

CLINICAL BACKGROUND: If pheochromocytoma (PC) or paraganglioma (PGL) is diagnosed based on serologic studies, imaging is required to locate the adrenal mass for further management. Besides pathognomonic hormonal findings, PC/PGL can exhibit typical imaging features. However, PC/PGL can also show morphological overlap with other pathologies. STANDARD RADIOLOGICAL METHODS: The modality of choice for evaluation of PC is CT. In case of extra-adrenal location, MRI is superior to CT. Imaging with PET-CT provides complementary information in the differentiation of PC/PGL and is recommended as the imaging modality of choice for malignant PC/PGL. 68Ga-DOTATATE (or 68Ga-DOTATOC/ 68Ga-DOTANOC) PET-CT has high sensitivity for SDHx-mutated PC/PGL and serves for planning of radioreceptor therapy with somatostatin analogues. In contrast, 123I-metaiodobenzylguanidine (MIBG) scintigraphy is important in assessing the potential efficacy of radioreceptor therapy with MIBG. METHODICAL DETAILS: The CT protocol for PC evaluation should include non-enhanced, arterial, portal-venous and late phases; the latter for the evaluation of wash-out. Recent studies indicate non-enhanced CT alone may be sufficient to rule out PC. For MRI, in- and opposed-phase sequences should be additionally acquired. PRACTICAL RECOMMENDATIONS: A relevant proportion of PC is diagnosed incidentally. Therefore, imaging of PC will gain further importance. Recent studies show better response rates of PC/PGL after radioreceptor therapy with somatostatin analogues (177Lu-DOTATATE) than with MIBG. Therefore, 68Ga-DOTATATE PET-CT gains further importance-for diagnostic imaging and therapy planning.


Assuntos
Neoplasias das Glândulas Suprarrenais , Paraganglioma , Feocromocitoma , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Paraganglioma/diagnóstico por imagem , Feocromocitoma/diagnóstico por imagem
11.
AJNR Am J Neuroradiol ; 40(3): 396-400, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30705072

RESUMO

The overwhelming benefit of endovascular therapy in patients with large-vessel occlusions suggests that more patients will be screened than treated. Some of those patients will be evaluated first at primary stroke centers; this type of evaluation calls for standardizing the imaging approach to minimize delays in assessing, transferring, and treating these patients. Here, we propose that CT angiography (performed at the same time as head CT) should be the minimum imaging approach for all patients with stroke with suspected large-vessel occlusion presenting to primary stroke centers. We discuss some of the implications of this approach and how to facilitate them.


Assuntos
Unidades Hospitalares , Neuroimagem/métodos , Neuroimagem/normas , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Angiografia por Tomografia Computadorizada/métodos , Procedimentos Endovasculares , Feminino , Unidades Hospitalares/organização & administração , Unidades Hospitalares/normas , Humanos , Masculino , Pessoa de Meia-Idade , Transferência de Pacientes , Acidente Vascular Cerebral/terapia , Tempo para o Tratamento , Tomografia Computadorizada por Raios X , Fluxo de Trabalho
13.
Phys Chem Chem Phys ; 18(36): 24850-8, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27397509

RESUMO

Silica gardens are tubular structures that form along the interface of multivalent metal salts and alkaline solutions of sodium silicate, driven by a complex interplay of osmotic and buoyant forces together with chemical reaction. They display peculiar plant-like morphologies and thus can be considered as one of the few examples for the spontaneous biomimetic self-ordering of purely inorganic materials. Recently, we could show that silica gardens moreover are highly dynamic systems that remain far from equilibrium for considerable periods of time long after macroscopic growth is completed. Due to initial compartmentalisation, drastic concentration gradients were found to exist across the tube walls, which give rise to noticeable electrochemical potential differences and decay only slowly in a series of coupled diffusion and precipitation processes. In the present work, we extend these studies and investigate the effect of the nature of the used metal cations on the dynamic behaviour of the system. To that end, we have grown single macroscopic silica garden tubes by controlled addition of sodium silicate sol to pellets of iron(ii) and iron(iii) chloride. In the following, the concentrations of ionic species were measured as a function of time on both sides of the formed membranes, while electrochemical potentials and pH were monitored online by immersing the corresponding sensors into the two separated solution reservoirs. At the end of the experiments, the solid tube material was furthermore characterised with respect to composition and microstructure by a combination of ex situ techniques. The collected data are compared to the previously reported case of cobalt-based silica gardens and used to shed light on ion diffusion through the inorganic membranes as well as progressive mineralisation at both surfaces of the tube walls. Our results reveal important differences in the dynamics of the three studied systems, which can be explained based on the acidity of the metal cations and the porosity of the membranes, leading to substantially dissimilar time-dependent solution chemistry as well as distinct final mineral structures. The insight gained in this work may help to better understand the diffusion properties and precipitation patterns in tubular iron (hydr)oxide/silicate structures observed in geological environments and during steel corrosion.

15.
AJNR Am J Neuroradiol ; 37(7): 1296-302, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26869467

RESUMO

BACKGROUND AND PURPOSE: The selection of patients for endovascular therapy is an important issue in stroke imaging. The aim of this study was to determine the predictive value of 3 different dynamic CT angiography parameters, occlusion length, collateralization extent, and time delay to maximum enhancement, for latest generation of stent retriever thrombectomy recanalization outcomes in patients with acute ischemic stroke. MATERIALS AND METHODS: In this study, subjects were selected from an initial cohort of 2059 consecutive patients who had undergone multiparametric CT, including whole-brain CT perfusion. We included all patients with a complete occlusion of the M1 segment of the MCA or the carotid T and subsequent intra-arterial stent retriever thrombectomy. Dynamic CT angiography was reconstructed from whole-brain CT perfusion raw datasets. Angiographic outcome was scored by using the modified TICI scale; and clinical outcome, by using the modified Rankin Scale. Logistic regression analyses were performed to determine independent predictors of a favorable angiographic (mTICI = 3) and clinical outcome (mRS ≤2). RESULTS: Sixty-nine patients (mean age, 68 ± 14 years; 46% men) were included for statistical analysis. In the regression analysis, a short occlusion length was an independent predictor of favorable angiographic outcome (OR, 0.41; P < .05). Both collateralization grade (OR, 1.00; P > .05) and time delay to peak enhancement (OR, 0.90; P > .05) failed to predict a favorable angiographic outcome. None of the dynamic CT angiography predictors were significantly associated with clinical outcome on discharge (OR, 0.664-1.011; P = .330-.953) or at 90 days (OR, 0.779-1.016; P = .130-.845). CONCLUSIONS: A short occlusion length as determined by dynamic CT angiography is an independent predictor of a favorable angiographic outcome of stent retriever thrombectomy in patients with ischemic stroke.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Trombectomia/métodos , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Stents , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
16.
Phys Chem Chem Phys ; 17(48): 32528-38, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26593697

RESUMO

We study the addition of electrolytes to surfactant-free microemulsions in the domain where polydisperse pre-Ouzo aggregates are present. As in previous studies, the microemulsion is the ternary system water/ethanol/1-octanol, where ethanol acts as co-solvent. Addition of electrolytes modifies the static X-ray and neutron scattering, and dynamic light scattering patterns, as well as the position of the miscibility gap, where spontaneous emulsification occurs upon dilution with water. All observations can be rationalized considering that electrolytes are either "salting out" the ethanol, which is the main component of the interface stabilizing the aggregates, or producing charge separation via the antagonistic ion effect discovered by Onuki et al. Amphiphilic electrolytes, such as sodium dodecylsulfate or sodium dietheylhexylphosphate, induce a gradual transition towards monodisperse ionic micelles with their characteristic broad scattering "peak". In these micelles the ethanol plays then the role of a cosurfactant. Dynamic light scattering can only be understood by combination of fluctuations of aggregate concentration due to the vicinity of a critical point and in-out fluctuations of ethanol.

17.
Water Sci Technol ; 66(8): 1691-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22907453

RESUMO

This paper presents the methodologies to determine odour in ambient air by field inspection that will be a new European standard. The objective is to characterise the odour in a defined area. Without making a link with potential annoyance due to the presence of odours, the described methods propose the way to characterise an exposed environment. Two approaches are defined in the new standard: the grid method and the plume method. The grid method can be used to determine the exposure to ambient odours in a defined area of study, using direct observation of recognisable odours in the field by human panel members. This method must be applied over a sufficiently long period of time (6 or 12 months) to be representative of the meteorological conditions of that location. The result is the distribution of the frequency of exposure to odours within the assessment area. The plume method can be used to determine the extent of detectable and recognisable odours from a specific source using direct observation in the field by human panel members under specific meteorological conditions.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Monitoramento Ambiental/normas , Odorantes/análise , Europa (Continente)
18.
J Mol Med (Berl) ; 90(10): 1145-60, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22411022

RESUMO

The role of mitochondrial dysfunction in the development of insulin resistance and type 2 diabetes remains controversial. In order to specifically define the relationship between insulin receptor (InsR) signaling, insulin resistance, hyperglycemia, hyperlipidemia and mitochondrial function, we analyzed mitochondrial performance of insulin-sensitive, slow-oxidative muscle in four different mouse models. In obese but normoglycemic ob/ob mice as well as in obese but diabetic mice under high-fat diet, mitochondrial performance remained unchanged even though intramyocellular diacylglycerols (DAGs), triacylglycerols (TAGs), and ceramides accumulated. In contrast, in muscle-specific InsR knockout (MIRKO) and streptozotocin (STZ)-treated hypoinsulinemic, hyperglycemic mice, levels of mitochondrial respiratory chain complexes and mitochondrial function were markedly reduced. In STZ, but not in MIRKO mice, this was caused by reduced transcription of mitochondrial genes mediated via decreased PGC-1α expression. We conclude that mitochondrial dysfunction is not causally involved in the pathogenesis of obesity-associated insulin resistance under normoglycemic conditions. However, obesity-associated type 2 diabetes and accumulation of DAGs or TAGs is not associated with impaired mitochondrial function. In contrast, chronic hypoinsulinemia and hyperglycemia as seen in STZ-treated mice as well as InsR deficiency in muscle of MIRKO mice lead to mitochondrial dysfunction. We postulate that decreased mitochondrial mass and/or performance in skeletal muscle of non-diabetic, obese or type 2 diabetic, obese patients observed in clinical studies must be explained by genetic predisposition, physical inactivity, or other still unknown factors.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Transporte de Elétrons , Resistência à Insulina , Insulina/fisiologia , Mitocôndrias Musculares/metabolismo , Obesidade/metabolismo , Transdução de Sinais , Animais , Autofagia , Glicemia , Carnitina O-Palmitoiltransferase/metabolismo , Diabetes Mellitus Experimental/sangue , Dieta Hiperlipídica/efeitos adversos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Expressão Gênica , Glucosilceramidas/metabolismo , Metabolismo dos Lipídeos , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Mitocôndrias Musculares/enzimologia , Mitocôndrias Musculares/fisiologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Obesidade/sangue , Obesidade/etiologia , Estresse Oxidativo , Consumo de Oxigênio , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Estreptozocina , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição
19.
Ophthalmology ; 118(9): 1747-53, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21788081

RESUMO

OBJECTIVE: To report clinical and histopathologic features of vascular tumors of the conjunctiva. DESIGN: Retrospective, noninterventional case series. PARTICIPANTS: A total of 140 patients. INTERVENTION: None. MAIN OUTCOME MEASURES: Tumor diagnosis, anatomic location, clinical features, management, and histopathology. RESULTS: There were 140 vascular tumors of the conjunctiva with 93% benign and 7% malignant. The specific diagnoses included lymphangioma/lymphangiectasis (n = 54, 36%), pyogenic granuloma (n = 31, 22%), capillary hemangioma (n = 20, 14%), Kaposi's sarcoma (n = 10, 7%), acquired sessile hemangioma (n = 10, 7%), racemose hemangioma (n = 7, 5%), varix (n = 4, 3%), cavernous hemangioma (n = 3, 2%), and glomangioma (n = 1, <1%). The lesions were unilateral in 89% and discovered at median age of 41 years. Bilateral lesions included lymphangiectasia, Kaposi's sarcoma, and racemose hemangioma. All tumors were typically found in adults with the exception of capillary hemangioma (<1 year) and glomangioma (16 years). The median tumor diameter was 6 mm, with the largest median diameter (15 mm) with Kaposi's sarcoma and (12 mm) glomangioma and capillary hemangioma and the smallest median diameter (3 mm) with cavernous hemangioma. The most common anatomic sites included bulbar conjunctiva, which was extralimbal in 80 patients (57%), limbal in 19 patients (14%), tarsal conjunctiva in 27 patients (19%), and forniceal conjunctival in 24 patients (17%). Clinical features included cystic component in 24% of patients (seen with lymphangioma, glomangioma, and varix), well-defined margins in 64% of patients, and feeder vessels in 39% of patients. CONCLUSIONS: A variety of vascular tumors can occur in both children and adults at various anatomic locations in the conjunctiva. They tend to occur unilaterally on the bulbar conjunctiva, and the majority of tumors are benign.


Assuntos
Neoplasias da Túnica Conjuntiva/patologia , Neoplasias de Tecido Vascular/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Neoplasias da Túnica Conjuntiva/terapia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Neoplasias de Tecido Vascular/terapia , Estudos Retrospectivos
20.
Neurology ; 74(6): 507-12, 2010 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-20142618

RESUMO

OBJECTIVE: To present 2 families with maternally inherited severe epilepsy as the main symptom of mitochondrial disease due to point mutations at position 616 in the mitochondrial tRNA(Phe) (MT-TF) gene. METHODS: Histologic stainings were performed on skeletal muscle slices from the 2 index patients. Oxidative phosphorylation activity was measured by oxygraphic and spectrophotometric methods. The patients' complete mitochondrial DNA (mtDNA) and the relevant mtDNA region in maternal relatives were sequenced. RESULTS: Muscle histology showed only decreased overall COX staining, while a combined respiratory chain defect, most severely affecting complex IV, was noted in both patients' skeletal muscle. Sequencing of the mtDNA revealed in both patients a mutation at position 616 in the MT-TF gene (T>C or T>G). These mutations disrupt a base pair in the anticodon stem at a highly conserved position. They were apparently homoplasmic in both patients, and had different heteroplasmy levels in the investigated maternal relatives. CONCLUSIONS: Deleterious mutations in the mitochondrial tRNA(Phe) may solely manifest with epilepsy when segregating to homoplasmy. They may be overlooked in the absence of lactate accumulation and typical mosaic mitochondrial defects in muscle.


Assuntos
DNA Mitocondrial/genética , Epilepsia/genética , Doenças Mitocondriais/genética , Doenças Mitocondriais/fisiopatologia , Mutação/genética , RNA de Transferência de Fenilalanina/genética , Adolescente , Anticonvulsivantes/uso terapêutico , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Epilepsia/complicações , Epilepsia/tratamento farmacológico , Saúde da Família , Feminino , Humanos , Masculino , Músculo Esquelético/patologia , Polimorfismo de Fragmento de Restrição , Succinato Desidrogenase/metabolismo , Adulto Jovem
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