322 results on '"Caldeira L"'
Search Results
202. Liposomal amphotericin B (AmBisome) in Mediterranean visceral leishmaniasis: a multi-centre trial
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DAVIDSON, R. N., MARTINO, L. DI, GRADONI, L., GIACCHINO, R., RUSSO, R., GAETA, G. B., PEMPINELLO, R., SCOTT, S., RAIMONDI, F., CASCIO, A., PRESTILEO, T., CALDEIRA, L., WILKINSON, R. J., and BRYCESON, A. D. M.
- Abstract
Thirty-one patients with visceral leishmaniasis (VL) caused by Leishmania infantum received liposomal amphotericin B (AmBisome) in a multi-centre study. Ten immunocompetent patients (six children) received 1–1.38 mg/kg/day for 21 days, and ten (nine children) received 3 mg/kg/day for 10 days. All were cured without significant adverse events and without relapse during 12–24 months of follow-up. Eleven immunocompromised adults, including seven co-infected with HIV (four with AIDS) received 100mg (1.38–1.85 mg/kg) daily for 21 days. All were initially considered cured, but eight relapsed clinically and parasitologically at 3–22 months. Liposomal amphotericin B is a new, safe and effective drug for the treatment of VL. - Published
- 1994
203. Unmanned aerial vehicles (UAV) as a support to visual inspections of concrete dams
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Henriques, M. J., Roque, D., Pina, C., Portela, E., Caldeira, L., Batista, A., Dias, I., and Santos, R.
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Point cloud ,Visual inspection ,Dam ,Orthomosaic ,Drone - Abstract
Drone or UAV (unmanned aerial vehicle) are the most common names used to refer light aircrafts without human pilots aboard. This paper presents one application that explores its use as a carrier of digital cameras, allowing the acquisition of images at distances of a few meters of a dam. Dams, and especially large dams, are structures that usually present high risk. For this reason they are subject to surveillance to evaluate its safety. Visual inspections contribute to the knowledge of the structure and are irreplaceable since some problems can only be detected, and their evolution followed, by this method. If to make a photographic reportage inside galleries or in other accessible areas is easy, when one must evaluate the state of the exterior walls or other inaccessible locations on dams, the only method available to inspect the surface was to set the camera/binoculars on the banks of the river. Drones can easily overcome this problem, since they can be guided near the structure, at distances of a few meters This paper presents the results of an experience made at Bouçã dam: it is described the UAV system used, the dam, the flights, the photogrammetric products generated (orthomosaic and point cloud), the problems faced. In Figures 1 and 2 are presented two photographs of Bouçã dam taken during this experiment by a digital camera carried by a drone octocopter. 12p DBB/NGA Second International DAM WORLD Conference Proceedings
- Published
- 2015
204. Geophysical methods applied to the assessment of the geological and geotechnical conditions of dam sites: the case study of Pedrógão dam (Portugal)
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Mota, R., Neves, J., Monteiro dos Santos, F. A., Pina, C., Portela, E., Caldeira, L., Batista, A., Dias, I., Santos, R., NAO, and SIM
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Geophysical methods ,Porosity section ,Foundation ,Geological-geotechnical data ,Water content section ,Dams - Abstract
Geophysical methods are indirect tools of investigation of the subsoil. Seldom is the geophysicist able to confirm the results of his models with the reality. In the case study of Pedrógão dam, this was possible. At this site several geophysical methods were applied and compared with the geological and geotechnical map of the excavations for the dam’s foundation. This analysis allowed the conclusion of a good match between the main geophysical anomalies of each physical parameter with the identi fied main geological structures, namely an important fault zone – that could be a seepage source -, and also a good fit of the predicted in depth development of the geotechnical zones. 12p DG/NGEA
- Published
- 2015
205. Hereditary angioedema: 24 years of experience in a Portuguese reference center.
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Varandas C, Esteves Caldeira L, Silva SL, Costa C, Limão R, Silva MI, Lopes A, Caiado J, Cosme J, Alonso E, Marcelino J, Cabral Duarte F, Fernandes NP, Neto M, Pedro E, Branco Ferreira M, and Spínola Santos A
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- Humans, Portugal epidemiology, Female, Male, Retrospective Studies, Adult, Adolescent, Cross-Sectional Studies, Child, Young Adult, Middle Aged, Prevalence, Child, Preschool, Delayed Diagnosis, Angioedemas, Hereditary diagnosis, Angioedemas, Hereditary epidemiology
- Abstract
Summary: Background. Hereditary angioedema (HAE) poses a high burden of disease, being its epidemiological and clinical data heterogeneous among countries, with no recent published studies concerning Portuguese patients. Therefore, we aimed to raise awareness of HAE and to contribute to clinical knowledge. Methods. An observational, descriptive, retrospective, and cross-sectional study was performed, that included a cohort of 126 patients followed in a single Portuguese Center. Results. We observed a high prevalence of HAE-C1-INH type II (45.2% of patients). Most HAE patients (67.4%) presented the initial manifestations of the disease before adulthood, at a mean age of 12.6 ± 8.4 years. However, we found a long delay in HAE diagnosis, especially in those without family history (mean 20.7 ± 17.3 years). Stress was the most common trigger, followed by trauma and infection. Symptoms involving different systems were increasingly reported with increased disease duration. Cutaneous symptoms (95.0%) were more frequent, followed by gastrointestinal (80.7%), and respiratory symptoms (50.4%). HAE symptoms led to abdominal surgery in 22 (17.5%) patients and induced laryngeal edema requiring intubation/tracheostomy in 8 (6.3%) patients. Most patients were under long-term prophylaxis, mainly with attenuated androgens (62.7% of patients). Conclusions. The correct distinction between HAE and other common causes of angioedema is critical, allowing reduction of diagnostic delay, improvement of adequate management, and ultimately improving outcomes and quality of life of HAE patients.
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- 2024
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206. Managing systemic reactions and venom immunotherapy in vespid-venom allergy: observations from a retrospective study of Portuguese patients.
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Ferreira SC, Gomes M, Vieira J, Caldeira L, Silva MI, Ferreira MB, Pedro E, and Cosme J
- Abstract
Summary: Background. Vespula spp. and Polistes spp. are relevant species in South Europe, with Vespa velutina nigrithorax (VVN) being considered a public health problem. We aimed to characterize a cohort of Portuguese patients referred for large local reaction (LLR) and/or systemic reaction (SR) to vespids. In patients treated with venom immunotherapy (VIT), induction protocol and frequency of adverse reactions were evaluated. Methods. Retrospective study including patients with LLR and SR to vespids referred to our Immunoallergology Department (2008-2022). Results. A total of 129 patients were evaluated, the majority were male adults (n = 77, 59.7%), from rural areas. From these, 51 patients had SR (Mueller classification: 7.8% grade I, 19.6% grade II, 37.3% grade III, 35.3% grade IV). We found no differences regarding the levels of total serum IgE, basal serum tryptase value, sIgE levels to the eliciting venom or their molecular components, regarding the severity of the SR that motivated the referral to our clinic. In the SR group, previous LLR Hymenoptera sting were reported in 15.7%. Thirty-eight patients (74.5%) initiated VIT: 22 with wasp venom, 14 with paper wasp venom and 2 with Vespa velutina venom. There was one mild systemic reaction, not requiring adrenaline and 4 LLR. Re-stings after VIT occurred in 16 patients, without any systemic or local reactions. Currently, eleven patients remain under VIT. Conclusions. Most vespid-venom allergic patients are male adults from rural areas. Sensitization to wasp venom was present in 52.9%, paper wasp in 33.3% and Vespa velutina in 13.7%. The frequency of adverse reactions during both induction and maintenance phases appears to be low. Despite a reduced sample size, our experience with VVN VIT, suggests its safety.
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- 2024
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207. Robustness of radiomic features in healthy abdominal parenchyma of patients with repeated examinations on dual-layer dual-energy CT.
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Schöneck M, Lennartz S, Zopfs D, Sonnabend K, Wawer Matos Reimer R, Rinneburger M, Graffe J, Persigehl T, Hentschke C, Baeßler B, Lourenco Caldeira L, and Große Hokamp N
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- Humans, Male, Female, Middle Aged, Aged, Adult, Retrospective Studies, Pancreas diagnostic imaging, Liver diagnostic imaging, Radiography, Abdominal methods, Aged, 80 and over, Spleen diagnostic imaging, Parenchymal Tissue diagnostic imaging, Psoas Muscles diagnostic imaging, Radiomics, Tomography, X-Ray Computed methods, Radiography, Dual-Energy Scanned Projection methods
- Abstract
Objectives: Robustness of radiomic features in physiological tissue is an important prerequisite for quantitative analysis of tumor biology and response assessment. In contrast to previous studies which focused on different tumors with mostly short scan-re-scan intervals, this study aimed to evaluate the robustness of radiomic features in cancer-free patients and over a clinically encountered inter-scan interval., Materials and Methods: Patients without visible tumor burden who underwent at least two portal-venous phase dual energy CT examinations of the abdomen between May 2016 and January 2020 were included, while macroscopic tumor burden was excluded based upon follow-up imaging for all patients (≥3 months). Further, patients were excluded if no follow-up imaging was available, or if the CT protocol showed deviations between repeated examinations. Circular regions of interest were placed and proofread by two board-certified radiologists (4 years and 5 years experience) within the liver (segments 3 and 6), the psoas muscle (left and right), the pancreatic head, and the spleen to obtain radiomic features from normal-appearing organ parenchyma using PyRadiomics. Radiomic feature robustness was tested using the concordance correlation coefficient with a threshold of 0.75 considered indicative for deeming a feature robust., Results: In total, 160 patients with 480 repeated abdominal CT examinations (range: 2-4 per patient) were retrospectively included in this single-center, IRB-approved study. Considering all organs and feature categories, only 4.58 % (25/546) of all features were robust with the highest rate being found in the first order feature category (20.37 %, 22/108). Other feature categories (grey level co-occurrence matrix, grey level dependence matrix, grey level run length matrix, grey level size zone matrix, and neighborhood gray-tone difference matrix) yielded an overall low percentage of robust features (range: 0.00 %-1.19 %). A subgroup analysis revealed the reconstructed field of view and the X-ray tube current as determinants of feature robustness (significant differences in subgroups for all organs, p < 0.001) as well as the size of the region of interest (no significant difference for the pancreatic head with p = 0.135, significant difference with p < 0.001 for all other organs)., Conclusion: Radiomic feature robustness obtained from cancer-free subjects with repeated examinations using a consistent protocol and CT scanner was limited, with first order features yielding the highest proportion of robust features., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Nils Große Hokamp: Research support, talk honoraria (Philips), consultancy (Bristol Myers Squibb); David Zopfs: Research support, talk honoraria (Philips); Kristina Sonnabend: Employee (Philips); Clemens Hentschke: Employee (Mint Medical GmbH); Bettina Baeßler: Speaker (Bayer Vital GmbH), founder and CEO of Lernrad GmbH; Liliana Lourenco Caldeira: Research support (Philips)., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
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208. Dual-layer dual-energy CT-derived pulmonary perfusion for the differentiation of acute pulmonary embolism and chronic thromboembolic pulmonary hypertension.
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Gertz RJ, Gerhardt F, Pienn M, Lennartz S, Kröger JR, Caldeira L, Pennig L, Schömig TH, Hokamp NG, Maintz D, Rosenkranz S, and Bunck AC
- Subjects
- Humans, Female, Male, Middle Aged, Retrospective Studies, Chronic Disease, Acute Disease, Diagnosis, Differential, Aged, Adult, Tomography, X-Ray Computed methods, Radiography, Dual-Energy Scanned Projection methods, Contrast Media, Sensitivity and Specificity, Pulmonary Artery diagnostic imaging, Pulmonary Artery physiopathology, Aged, 80 and over, Pulmonary Embolism diagnostic imaging, Pulmonary Embolism complications, Pulmonary Embolism physiopathology, Hypertension, Pulmonary diagnostic imaging, Hypertension, Pulmonary physiopathology, Computed Tomography Angiography methods
- Abstract
Objectives: To evaluate dual-layer dual-energy computed tomography (dlDECT)-derived pulmonary perfusion maps for differentiation between acute pulmonary embolism (PE) and chronic thromboembolic pulmonary hypertension (CTEPH)., Methods: This retrospective study included 131 patients (57 patients with acute PE, 52 CTEPH, 22 controls), who underwent CT pulmonary angiography on a dlDECT. Normal and malperfused areas of lung parenchyma were semiautomatically contoured using iodine density overlay (IDO) maps. First-order histogram features of normal and malperfused lung tissue were extracted. Iodine density (ID) was normalized to the mean pulmonary artery (MPA) and the left atrium (LA). Furthermore, morphological imaging features for both acute and chronic PE, as well as the combination of histogram and morphological imaging features, were evaluated., Results: In acute PE, normal perfused lung areas showed a higher mean and peak iodine uptake normalized to the MPA than in CTEPH (both p < 0.001). After normalizing mean ID in perfusion defects to the LA, patients with acute PE had a reduced average perfusion (ID
mean,LA ) compared to both CTEPH patients and controls (p < 0.001 for both). IDmean,LA allowed for a differentiation between acute PE and CTEPH with moderate accuracy (AUC: 0.72, sensitivity 74%, specificity 64%), resulting in a PPV and NPV for CTEPH of 64% and 70%. Combining IDmean,LA in the malperfused areas with the diameter of the MPA (MPAdia ) significantly increased its ability to differentiate between acute PE and CTEPH (sole MPAdia : AUC: 0.76, 95%-CI: 0.68-0.85 vs. MPAdia + 256.3 * IDmean,LA - 40.0: AUC: 0.82, 95%-CI: 0.74-0.90, p = 0.04)., Conclusion: dlDECT enables quantification and characterization of pulmonary perfusion patterns in acute PE and CTEPH. Although these lack precision when used as a standalone criterion, when combined with morphological CT parameters, they hold potential to enhance differentiation between the two diseases., Clinical Relevance Statement: Differentiating between acute PE and CTEPH based on morphological CT parameters is challenging, often leading to a delay in CTEPH diagnosis. By revealing distinct pulmonary perfusion patterns in both entities, dlDECT may facilitate timely diagnosis of CTEPH, ultimately improving clinical management., Key Points: • Morphological imaging parameters derived from CT pulmonary angiography to distinguish between acute pulmonary embolism and chronic thromboembolic pulmonary hypertension lack diagnostic accuracy. • Dual-layer dual-energy CT reveals different pulmonary perfusion patterns between acute pulmonary embolism and chronic thromboembolic pulmonary hypertension. • The identified parameters yield potential to enable more timely identification of patients with chronic thromboembolic pulmonary hypertension., (© 2023. The Author(s).)- Published
- 2024
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209. Atopy and Response to Omalizumab Treatment in Chronic Spontaneous Urticaria.
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Costa C, Esteves Caldeira L, Paulino M, Santos DF, and Silva SL
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- Adult, Female, Humans, Male, Middle Aged, Chronic Disease, Chronic Inducible Urticaria, Immunoglobulin E, Omalizumab therapeutic use, Retrospective Studies, Treatment Outcome, Angioedema, Anti-Allergic Agents therapeutic use, Chronic Urticaria drug therapy, Urticaria drug therapy
- Abstract
Introduction: The possible influence of sensitization to aeroallergens on omalizumab response in chronic spontaneous urticaria (CSU) has been insufficiently investigated. This study's aim was to investigate atopy's influence on omalizumab response in CSU patients., Method: Retrospective study of CSU patients followed at a Portuguese Urticaria Center of Reference and Excellence (UCARE), treated with omalizumab for at least 6 months, between 2015 and 2022. At T0, all patients underwent quantification of specific immunoglobulin E (IgE) for total extract of most prevalent aeroallergens (ImmunoCAP Thermo Fisher Scientific®) and were divided in 2 groups, according to their response to omalizumab during the first 16 weeks of treatment: responders (R) (UAS7 <7) versus partial (PR) (UAS7 = 7-15) and nonresponders (UAS7 >15). R were further classified as fast (FR) (4-6 weeks) and slow responders (SR) (12-16 weeks). Total serum IgE, circulating eosinophil, and basophil counts were compared between groups at T0. p < 0.05 was considered statistically significant (SPSS® v25.0)., Results: Ninety-six patients (80% female) were studied, mean age 49 ± 14 years. Median CSU duration pre-omalizumab was 3 (0.6-20) years and mean omalizumab treatment duration was 3.7 ± 2.3 years. 38 (40%) had concomitant chronic inducible urticaria and 72 (75%) angioedema. Based on positive results of the specific IgE assay, 35 patients (36%) were considered atopic. Most patients (n = 30; 86%) were sensitized to house dust mites (HDM) (Dermatophagoides farinae = 28, Dermatophagoides pteronyssinus = 27, Blomia tropicalis = 19, Lepidoglyphus destructor = 17), followed by pollens (n = 12; 34%) (mixture of grasses = 10, Olea europaea = 7, Parietaria officinalis = 6), epithelia (n = 9; 26%) (dog = 8, cat = 7), and fungi (Alternaria alternata = 4; 11%). Eight patients (23%) were monosensitized to HDM and 4 (11%) to pollens. No significant association was found between aeroallergen sensitization and CSU duration, concomitant chronic inducible urticaria, or angioedema. Atopic patients featured significantly higher levels of baseline total serum IgE than nonatopic (469 vs. 94 U/mL, respectively; p = 0.0009). Mean baseline counts of eosinophils and basophils were not significantly different between atopic and non-atopic, respectively: eosinophils (128 vs. 121/mm3) and basophils (26 vs. 28/mm3). Regarding response to omalizumab, most patients (58; 60%) were responders: FR - 46 (79%); SR - 12 (21%). There was no significant association between aeroallergen sensitization and omalizumab response or speed of response., Conclusions: As far as we know, this is the first study exploring the influence of atopy sensitization pattern on omalizumab response in CSU. According to our results, presence of atopy/sensitization pattern does not influence omalizumab response in CSU patients., (© 2023 S. Karger AG, Basel.)
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- 2024
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210. Four-week total IgE/baseline total IgE ratio: Biomarker for omalizumab good response in chronic spontaneous urticaria real-life patients.
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Esteves Caldeira L, Bernardino A, Paulino M, and Costa C
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- 2023
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211. Deep-Learning-Based Image Denoising in Imaging of Urolithiasis: Assessment of Image Quality and Comparison to State-of-the-Art Iterative Reconstructions.
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Terzis R, Reimer RP, Nelles C, Celik E, Caldeira L, Heidenreich A, Storz E, Maintz D, Zopfs D, and Große Hokamp N
- Abstract
This study aimed to compare the image quality and diagnostic accuracy of deep-learning-based image denoising reconstructions (DLIDs) to established iterative reconstructed algorithms in low-dose computed tomography (LDCT) of patients with suspected urolithiasis. LDCTs (CTDIvol, 2 mGy) of 76 patients (age: 40.3 ± 5.2 years, M/W: 51/25) with suspected urolithiasis were retrospectively included. Filtered-back projection (FBP), hybrid iterative and model-based iterative reconstruction (HIR/MBIR, respectively) were reconstructed. FBP images were processed using a Food and Drug Administration (FDA)-approved DLID. ROIs were placed in renal parenchyma, fat, muscle and urinary bladder. Signal- and contrast-to-noise ratios (SNR/CNR, respectively) were calculated. Two radiologists evaluated image quality on five-point Likert scales and urinary stones. The results showed a progressive decrease in image noise from FBP, HIR and DLID to MBIR with significant differences between each method ( p < 0.05). SNR and CNR were comparable between MBIR and DLID, while it was significantly lower in HIR followed by FBP (e.g., SNR: 1.5 ± 0.3; 1.4 ± 0.4; 1.0 ± 0.3; 0.7 ± 0.2, p < 0.05). Subjective analysis confirmed best image quality in MBIR, followed by DLID and HIR, both being superior to FBP ( p < 0.05). Diagnostic accuracy for urinary stone detection was best using MBIR (0.94), lowest using FBP (0.84) and comparable between DLID (0.90) and HIR (0.90). Stone size measurements were consistent between all reconstructions and showed excellent correlation (r
2 = 0.958-0.975). In conclusion, MBIR yielded the highest image quality and diagnostic accuracy, with DLID producing better results than HIR and FBP in image quality and matching HIR in diagnostic precision.- Published
- 2023
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212. Automated localization and segmentation of cervical lymph nodes on contrast-enhanced CT using a 3D foveal fully convolutional neural network.
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Rinneburger M, Carolus H, Iuga AI, Weisthoff M, Lennartz S, Hokamp NG, Caldeira L, Shahzad R, Maintz D, Laqua FC, Baeßler B, Klinder T, and Persigehl T
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- Humans, Retrospective Studies, Tomography, X-Ray Computed methods, Neoplasm Staging, Neural Networks, Computer, Lymph Nodes diagnostic imaging, Lymph Nodes pathology
- Abstract
Background: In the management of cancer patients, determination of TNM status is essential for treatment decision-making and therefore closely linked to clinical outcome and survival. Here, we developed a tool for automatic three-dimensional (3D) localization and segmentation of cervical lymph nodes (LNs) on contrast-enhanced computed tomography (CECT) examinations., Methods: In this IRB-approved retrospective single-center study, 187 CECT examinations of the head and neck region from patients with various primary diseases were collected from our local database, and 3656 LNs (19.5 ± 14.9 LNs/CECT, mean ± standard deviation) with a short-axis diameter (SAD) ≥ 5 mm were segmented manually by expert physicians. With these data, we trained an independent fully convolutional neural network based on 3D foveal patches. Testing was performed on 30 independent CECTs with 925 segmented LNs with an SAD ≥ 5 mm., Results: In total, 4,581 LNs were segmented in 217 CECTs. The model achieved an average localization rate (LR), i.e., percentage of localized LNs/CECT, of 78.0% in the validation dataset. In the test dataset, average LR was 81.1% with a mean Dice coefficient of 0.71. For enlarged LNs with a SAD ≥ 10 mm, LR was 96.2%. In the test dataset, the false-positive rate was 2.4 LNs/CECT., Conclusions: Our trained AI model demonstrated a good overall performance in the consistent automatic localization and 3D segmentation of physiological and metastatic cervical LNs with a SAD ≥ 5 mm on CECTs. This could aid clinical localization and automatic 3D segmentation, which can benefit clinical care and radiomics research., Relevance Statement: Our AI model is a time-saving tool for 3D segmentation of cervical lymph nodes on contrast-enhanced CT scans and serves as a solid base for N staging in clinical practice and further radiomics research., Key Points: • Determination of N status in TNM staging is essential for therapy planning in oncology. • Segmenting cervical lymph nodes manually is highly time-consuming in clinical practice. • Our model provides a robust, automated 3D segmentation of cervical lymph nodes. • It achieves a high accuracy for localization especially of enlarged lymph nodes. • These segmentations should assist clinical care and radiomics research., (© 2023. The Author(s).)
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- 2023
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213. Artificial Intelligence in Ophthalmology - Status Quo and Future Perspectives.
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Wawer Matos PA, Reimer RP, Rokohl AC, Caldeira L, Heindl LM, and Große Hokamp N
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- Humans, Artificial Intelligence, Machine Learning, Neural Networks, Computer, Diabetic Retinopathy, Ophthalmology methods
- Abstract
Artificial intelligence (AI) is an emerging technology in healthcare and holds the potential to disrupt many arms in medical care. In particular, disciplines using medical imaging modalities, including e.g. radiology but ophthalmology as well, are already confronted with a wide variety of AI implications. In ophthalmologic research, AI has demonstrated promising results limited to specific diseases and imaging tools, respectively. Yet, implementation of AI in clinical routine is not widely spread due to availability, heterogeneity in imaging techniques and AI methods. In order to describe the status quo, this narrational review provides a brief introduction to AI ("what the ophthalmologist needs to know"), followed by an overview of different AI-based applications in ophthalmology and a discussion on future challenges. Abbreviations : Age-related macular degeneration, AMD; Artificial intelligence, AI; Anterior segment OCT, AS-OCT; Coronary artery calcium score, CACS; Convolutional neural network, CNN; Deep convolutional neural network, DCNN; Diabetic retinopathy, DR; Machine learning, ML; Optical coherence tomography, OCT; Retinopathy of prematurity, ROP; Support vector machine, SVM; Thyroid-associated ophthalmopathy, TAO.
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- 2023
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214. A real-world characterization of a cohort with eosinophilic esophagitis: looking for severity biomarkers.
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Esteves Caldeira L, Limão R, Brás R, Pedro E, and Costa C
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Summary: Background. Eosinophilic esophagitis (EoE) is an immune-mediated chronic esophageal disease, with frequent association with atopy. A validated non/minimally invasive biomarker of disease severity has not been identified. We aimed to determine if sensitization to airborne and food allergens correlates with disease severity, and to evaluate the association between clinical and laboratory characteristics with the severity of EoE. Methods. Retrospective study of EoE patients observed in a differentiated center, 2009-2021. The association between patients' diagnosis age, disease duration before diagnosis, sensitization to airborne/food allergens, serum total IgE and peripheral blood eosinophil values and severe clinical disease (presence of symptoms with a significant impact on quality of life and/or ≥ 1 hospital admission due to EoE complications, namely severe dysphagia, food impaction or esophageal perforation) and histological severe disease (≥ 55 eos/hpf and/or microabscesses in esophageal biopsies) was evaluated. Results. 92 patients were observed, 83% male, 87% atopic. There was a mean delay in diagnosis of 4 years (range 0-31). 84% had aeroallergen sensitization and 71% food sensitization. Food impaction and dysphagia were the most frequent symptoms, and severe clinical disease was observed in 55%. Histologically, 37% had severity criteria. Patients with severe clinical disease had a significantly longer mean disease duration before diagnosis than patients without severe clinical disease (79 vs 15 months, p = 0.021). Patients who described food impaction were significantly older at time of diagnosis than those who have never had impaction (18 vs 9 years, p less than 0.001). There was no significant association (p less than 0.05) between sensitization, serum total IgE and peripheral blood eosinophil values and clinical or histological severity. Conclusions. An older age at diagnosis and a longer disease duration before diagnosis appear to be useful for predicting EoE clinical severity. Despite having been demonstrated a high prevalence of allergic disease, the presence of sensitization to airborne and/or food allergens do not seem to be useful for predicting clinical or histological severity.
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- 2023
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215. Anti-TPO IgG/Total IgE Ratio: Biomarker for Omalizumab Response Prediction in Chronic Spontaneous Urticaria.
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Brás R, Esteves Caldeira L, Bernardino A, and Costa C
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- Humans, Female, Middle Aged, Male, Omalizumab therapeutic use, Retrospective Studies, Immunosuppressive Agents therapeutic use, Biomarkers, Immunoglobulin E, Immunoglobulin G, Chronic Disease, Treatment Outcome, Urticaria diagnosis, Urticaria drug therapy, Chronic Urticaria diagnosis, Chronic Urticaria drug therapy, Anti-Allergic Agents therapeutic use
- Abstract
Background: According to recently published data, low total IgE, elevated IgG-anti-TPO, and a high IgG-anti-TPO/total IgE ratio are good biomarkers for subtype IIb autoimmune chronic spontaneous urticaria (CSU), which is frequently refractory to antihistamines and omalizumab., Objectives: The aim of the study was to evaluate IgG-anti-TPO/total IgE ratio's utility in omalizumab response prediction., Methods: Retrospective study of CSU patients treated with omalizumab at a UCARE between January 2009 and February 2022. Patients were grouped according to response in the first 16 weeks of treatment: responders UAS7 < 7 versus partial/non-responders UAS7≥7. Total IgE, IgG-anti-TPO, and IgG-anti-TPO/total IgE ratio were compared. Other inflammatory biomarkers - eosinophils, basophils, C-reactive protein, erythrocyte sedimentation rate, and d-dimer - were analyzed., Statistical Analysis: SPSS® (v25.0), p < 0.05 statistically significant., Results: Total of 175 patients, 140 (80%) women, median age 49 [9-88] years, mean CSU duration pre-omalizumab 5.6 ± 8.2 [0-54] years, omalizumab duration 3.2 ± 2.5 [0-12] years. 116 (66%) had angioedema, 77 (44%) inducible chronic urticaria, 60 (34%) atopy, 24 (14%) autoimmune disease. With omalizumab 300 mg q4 weeks, 69% were responders and 31% partial/non-responders. Although not reaching significant differences, mean total IgE values were lower and mean IgG-anti-TPO values were higher in partial/non-responders versus responders (152 vs. 242 kU/L, p = 0.207, and 38.3 vs. 25.7 U/mL, p = 0.408, respectively). A higher IgG-anti-TPO/total IgE ratio was significantly associated with poorer response to omalizumab (p = 0.040). A cut-off >0.154 increased 10 times the odd of poorer response [95% CI 4.62-22], AUC 0.872, p < 0.001, with 87.7% sensitivity, although the low specificity (22.4%) does not allow the assumption of response with values <0.154. Other laboratory biomarkers did not show significant differences between partial/non-responders versus responders., Conclusions: A high IgG-anti-TPO/total IgE ratio was a good biomarker of poor response to omalizumab in our CSU cohort, with a cut-off >0.154 increasing 10 times the odd of poorer response., (© 2023 S. Karger AG, Basel.)
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- 2023
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216. HCV reinfection after HCV therapy among HIV/HCV-coinfected individuals in Europe.
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Amele S, Sandri AK, Rodger A, Vandekerckhove L, Benfield T, Milinkovic A, Duvivier C, Stellbrink HJ, Sambatakou H, Chkhartishvili N, Caldeira L, Laguno M, Domingo P, Wandeler G, Gisinger M, Kuzovatova E, Dragovic G, Knysz B, Matulionyte R, Rockstroh JK, Lundgren JD, Mocroft A, and Peters L
- Subjects
- Antiviral Agents therapeutic use, Europe epidemiology, Female, Hepacivirus genetics, Humans, Male, Middle Aged, Reinfection, Coinfection complications, Coinfection drug therapy, HIV Infections complications, HIV Infections drug therapy, Hepatitis C, Chronic complications, Hepatitis C, Chronic drug therapy
- Abstract
Objectives: Although direct-acting antivirals (DAAs) can clear HCV in nearly all HIV/HCV-coinfected individuals, high rates of reinfection may hamper efforts to eliminate HCV in this population. We investigated reinfection after sustained virological response (SVR) in HIV/HCV-coinfected individuals in Europe., Methods: Factors associated with odds of reinfection by 2 years after SVR in EuroSIDA participants with one or more HCV-RNA test and 2 years follow-up were assessed using logistic regression., Results: Overall, 1022 individuals were included. The median age was 50 (interquartile range: 43-54 years), and most were male (78%), injection drug users (52%), and received interferon (IFN)-free DAAs (62%). By 24 months, 75 [7.3%, 95% confidence interval (CI): 5.7-8.9%] individuals were reinfected. Among individuals treated prior to 2014, 16.1% were reinfected compared with 4.2% and 8.3%, respectively, among those treated during or after 2014 with IFN-free and IFN-based therapy. After adjustment, individuals who had started treatment during or after 2014 with IFN-free or IFN-based therapy had significantly lower odds of reinfection (adjusted odds ratio = 0.21, 95% CI: 0.11-0.38; 0.43, 95% CI: 0.22-0.83) compared with those who had received therapy before 2014. There were no significant differences in odds of reinfection according to age, gender, European region, HIV transmission risk group or liver fibrosis., Conclusions: Among HIV/HCV-coinfected individuals in Europe, 7.3% were reinfected with HCV within 24 months of achieving SVR, with evidence suggesting that this is decreasing over time and with use of newer HCV regimens. Harm reduction to reduce reinfection and surveillance to detect early reinfection with an offer of treatment are essential to eliminate HCV., (© 2021 British HIV Association.)
- Published
- 2022
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217. Retrospective Study of the Epidemiological Profile of Facial Trauma Related to Violence.
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Caldeira L, Borges H, Simonetti T, Freddo AL, and Corsetti A
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- Adult, Aggression, Cross-Sectional Studies, Female, Humans, Male, Retrospective Studies, Facial Injuries epidemiology, Facial Injuries etiology, Violence
- Abstract
Abstract: Facial trauma is now considered an epidemic due to its high incidence. This type of injury represents an impact on the social, psychological and professional life of the victim. It may be associated with poor protection and exposure of this region of the body, as well as with the attempt to disfigure the face of victims of aggression, to affect their identity and self-image. This study aims to carry out an epidemiological survey on the profile of facial trauma related to violence at the First Aid Hospital of Porto Alegre from November 2015 to July 2016. In this retrospective descriptive cross-sectional study, data such as age and sex of the patient, type of trauma, anatomical region, etiology, and reasons for the aggression of patients' records were analyzed using the Chi-Square test in Paws Statistics 18 software, evaluating P < 0.05. During the period evaluated, 1224 cases were recorded. The most prevalent sex was male. The age group with the most injuries varied from 21 to 40. The most affected type of lesion was soft tissue injury. Scalp regions (parietal, occipital, temporal) and multiple regions were the most affected in males, differing from females, where the frontal and nasal regions were the most predominant. Violence is a major risk factor for facial trauma in adult patients and it is from epidemiological studies like this that we have the possibility to know the magnitude and severity of the results of violence, allowing the definition of public policies for coping., Competing Interests: The authors report no conflicts of interest., (Copyright © 2021 by Mutaz B. Habal, MD.)
- Published
- 2022
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218. A Linearized Fit Model for Robust Shape Parameterization of FET-PET TACs.
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Lerche CW, Radomski T, Lohmann P, Caldeira L, Brambilla CR, Tellmann L, Scheins J, Kops ER, Galldiks N, Langen KJ, Herzog H, and Jon Shah N
- Subjects
- Adult, Humans, Kinetics, Positron-Emission Tomography, Tyrosine, Brain Neoplasms diagnostic imaging, Glioma diagnostic imaging
- Abstract
The kinetic analysis of [Formula: see text]-FET time-activity curves (TAC) can provide valuable diagnostic information in glioma patients. The analysis is most often limited to the average TAC over a large tissue volume and is normally assessed by visual inspection or by evaluating the time-to-peak and linear slope during the late uptake phase. Here, we derived and validated a linearized model for TACs of [Formula: see text]-FET in dynamic PET scans. Emphasis was put on the robustness of the numerical parameters and how reliably automatic voxel-wise analysis of TAC kinetics was possible. The diagnostic performance of the extracted shape parameters for the discrimination between isocitrate dehydrogenase (IDH) wildtype (wt) and IDH-mutant (mut) glioma was assessed by receiver-operating characteristic in a group of 33 adult glioma patients. A high agreement between the adjusted model and measured TACs could be obtained and relative, estimated parameter uncertainties were small. The best differentiation between IDH-wt and IDH-mut gliomas was achieved with the linearized model fitted to the averaged TAC values from dynamic FET PET data in the time interval 4-50 min p.i.. When limiting the acquisition time to 20-40 min p.i., classification accuracy was only slightly lower (-3%) and was comparable to classification based on linear fits in this time interval. Voxel-wise fitting was possible within a computation time ≈ 1 min per image slice. Parameter uncertainties smaller than 80% for all fits with the linearized model were achieved. The agreement of best-fit parameters when comparing voxel-wise fits and fits of averaged TACs was very high (p < 0.001).
- Published
- 2021
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219. Antibody response against selected epitopes in the HIV-1 envelope gp41 ectodomain contributes to reduce viral burden in HIV-1 infected patients.
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Marcelino R, Gramacho F, Martin F, Brogueira P, Janeiro N, Afonso C, Badura R, Valadas E, Mansinho K, Caldeira L, Taveira N, and Marcelino JM
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- CD4 Lymphocyte Count, Humans, Viral Load, CD4-Positive T-Lymphocytes immunology, Epitopes immunology, HIV Antibodies immunology, HIV Envelope Protein gp41 immunology, HIV Infections immunology, HIV-1 immunology
- Abstract
The ectodomain of gp41 is the target of potent binding and neutralizing antibodies (NAbs) and is being explored in new strategies for antibody-based HIV vaccines. Previous studies have suggested that the W164A-3S (3S) and EC26-2A4 (EC26) peptides located in the gp41 ectodomain may be potential HIV vaccine candidates. We assessed 3S- and EC26-specific binding antibody responses and related neutralizing activity in a large panel of chronic HIV-1-infected Portuguese individuals on ART. A similar proportion of participants had antibodies binding to 3S (9.6%) and EC26 (9.9%) peptides but the level of reactivity against 3S was significantly higher compared to EC26, except in the rare patients with double peptide reactivity. The higher antigenicity of 3S was unrelated with disease stage, as assessed by CD4
+ T cell counts, but it was directly related with plasma viral load. Most patients that were tested (89.9%, N = 268) showed tier 1 neutralizing activity, the potency being inversely associated with plasma viral load. In the subset of patients that were tested for neutralization of tier 2 isolates, neutralization breadth was inversely correlated with plasma viral load and directly correlated with CD4+ T cell counts. These results are consistent with a role for neutralizing antibodies in controlling viral replication and preventing the decline of CD4+ T lymphocytes. Importantly, in patients with 3S-specific antibodies, neutralizing titers were inversely correlated with viral RNA levels and proviral DNA levels. Moreover, patients with 3S and/or EC26-specific antibodies showed a 1.9-fold higher tier 2 neutralization score than patients without antibodies suggesting that 3S and/or EC26-specific antibodies contribute to neutralization breadth and potency in HIV-1 infected patients. Overall, these results suggest that antibodies targeting the S3 and EC26 epitopes may contribute to reduce viral burden and provide further support for the inclusion of 3S and EC26 epitopes in HIV-1 vaccine candidates.- Published
- 2021
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220. Automated Detection and Segmentation of Brain Metastases in Malignant Melanoma: Evaluation of a Dedicated Deep Learning Model.
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Pennig L, Shahzad R, Caldeira L, Lennartz S, Thiele F, Goertz L, Zopfs D, Meißner AK, Fürtjes G, Perkuhn M, Kabbasch C, Grau S, Borggrefe J, and Laukamp KR
- Subjects
- Automation, Humans, Magnetic Resonance Imaging, Brain Neoplasms diagnostic imaging, Brain Neoplasms secondary, Deep Learning, Melanoma diagnostic imaging, Melanoma secondary, Skin Neoplasms diagnostic imaging
- Abstract
Background and Purpose: Malignant melanoma is an aggressive skin cancer in which brain metastases are common. Our aim was to establish and evaluate a deep learning model for fully automated detection and segmentation of brain metastases in patients with malignant melanoma using clinical routine MR imaging., Materials and Methods: Sixty-nine patients with melanoma with a total of 135 brain metastases at initial diagnosis and available multiparametric MR imaging datasets (T1-/T2-weighted, T1-weighted gadolinium contrast-enhanced, FLAIR) were included. A previously established deep learning model architecture (3D convolutional neural network; DeepMedic) simultaneously operating on the aforementioned MR images was trained on a cohort of 55 patients with 103 metastases using 5-fold cross-validation. The efficacy of the deep learning model was evaluated using an independent test set consisting of 14 patients with 32 metastases. Manual segmentations of metastases in a voxelwise manner (T1-weighted gadolinium contrast-enhanced imaging) performed by 2 radiologists in consensus served as the ground truth., Results: After training, the deep learning model detected 28 of 32 brain metastases (mean volume, 1.0 [SD, 2.4] cm
3 ) in the test cohort correctly (sensitivity of 88%), while false-positive findings of 0.71 per scan were observed. Compared with the ground truth, automated segmentations achieved a median Dice similarity coefficient of 0.75., Conclusions: Deep learning-based automated detection and segmentation of brain metastases in malignant melanoma yields high detection and segmentation accuracy with false-positive findings of <1 per scan., (© 2021 by American Journal of Neuroradiology.)- Published
- 2021
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221. Texture analysis of iodine maps and conventional images for k-nearest neighbor classification of benign and metastatic lung nodules.
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Lennartz S, Mager A, Große Hokamp N, Schäfer S, Zopfs D, Maintz D, Reinhardt HC, Thomas RK, Caldeira L, and Persigehl T
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- Female, Humans, Male, Middle Aged, Fluorodeoxyglucose F18 therapeutic use, Iodine metabolism, Lung Neoplasms classification, Lung Neoplasms diagnostic imaging, Positron Emission Tomography Computed Tomography methods, Tomography, X-Ray Computed methods
- Abstract
Background: The purpose of this study was to analyze if the use of texture analysis on spectral detector CT (SDCT)-derived iodine maps (IM) in addition to conventional images (CI) improves lung nodule differentiation, when being applied to a k-nearest neighbor (KNN) classifier., Methods: 183 cancer patients who underwent contrast-enhanced, venous phase SDCT of the chest were included: 85 patients with 146 benign lung nodules (BLN) confirmed by either prior/follow-up CT or histopathology and 98 patients with 425 lung metastases (LM) verified by histopathology,
18 F-FDG-PET-CT or unequivocal change during treatment. Semi-automatic 3D segmentation of BLN/LM was performed, and volumetric HU attenuation and iodine concentration were acquired. For conventional images and iodine maps, average, standard deviation, entropy, kurtosis, mean of the positive pixels (MPP), skewness, uniformity and uniformity of the positive pixels (UPP) within the volumes of interests were calculated. All acquired parameters were transferred to a KNN classifier., Results: Differentiation between BLN and LM was most accurate, when using all CI-derived features combined with the most significant IM-derived feature, entropy (Accuracy:0.87; F1/Dice:0.92). However, differentiation accuracy based on the 4 most powerful CI-derived features performed only slightly inferior (Accuracy:0.84; F1/Dice:0.89, p=0.125). Mono-parametric lung nodule differentiation based on either feature alone (i.e. attenuation or iodine concentration) was poor (AUC=0.65, 0.58, respectively)., Conclusions: First-order texture feature analysis of contrast-enhanced staging SDCT scans of the chest yield accurate differentiation between benign and metastatic lung nodules. In our study cohort, the most powerful iodine map-derived feature slightly, yet insignificantly increased classification accuracy compared to classification based on conventional image features only.- Published
- 2021
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222. The prevalence and risk-factors of oral HPV DNA detection among HIV-infected men between men who have sex with men and heterosexual men.
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Gonçalves HM, Silva J, Pintado Maury I, Tavares A, Campos C, Sousa H, Jacinto A, Aguiar P, Caldeira L, and Medeiros R
- Subjects
- Cross-Sectional Studies, Female, Heterosexuality, Homosexuality, Male, Humans, Male, Papillomaviridae genetics, Prevalence, Risk Factors, Sexual Behavior, HIV Infections complications, HIV Infections epidemiology, Papillomavirus Infections complications, Papillomavirus Infections epidemiology, Sexual and Gender Minorities
- Abstract
Background: Human papillomavirus (HPV)-associated oropharyngeal carcinomas are becoming more common with epidemiological impact on human immunodeficiency virus (HIV)- positive individuals. Objective: We evaluated prevalence and risk factors for oral HPV DNA among HIV-infected men who have sex with men (MSM) or heterosexual men. Methods: This cross-sectional hospital-based study included 255 HIV-infected men with different sexual orientation 142 MSM and 113 heterosexual men, who answered a self-administered questionnaire on sociodemographic, clinical and behavioural data. Oral swab and mouthwash samples were analysed by polymerase chain reaction and genotyped by Anyplex
TM II 28 (Seegene® ). Results: Oral HPV was detected in 17.6% (95% Confidence Interval (CI) 13.5-22.8%), 17.6% in MSM and 17.7% in heterosexual men ( p = .984). Multiple HPV infections were detected in 86.7% of HPV-positive men. HPV 56 (13.7%) was the most prevalent high-risk genotype, HPV 66 (7.8%) and HPV 70 (12.3%) were the most prevalent probable HR and low-risk HPV genotypes (12.3% and 7.1%, respectively). At multivariable analysis models, oral HPV was associated with >100 lifetime sexual partners (Odds Ratio (OR) 3.73; 95% CI 1.42-9.77) or lifetime tongue-kissing partners (OR 3.20; 95% CI 1.22-8.39) and lower education level (OR 2.90; 95% CI 1.08-7.78 and 2.74; 95% CI 1.04-7.27, respectively). Conclusions: Oral HPV prevalence was similar between HIV-infected MSM and heterosexual men. Oral HPV was associated with lifetime sexual partners, lifetime tongue-kissing partners and being undergraduate, independently of sexual orientation.- Published
- 2021
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223. Primary Central Nervous System Lymphoma: Clinical Evaluation of Automated Segmentation on Multiparametric MRI Using Deep Learning.
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Pennig L, Hoyer UCI, Goertz L, Shahzad R, Persigehl T, Thiele F, Perkuhn M, Ruge MI, Kabbasch C, Borggrefe J, Caldeira L, and Laukamp KR
- Subjects
- Central Nervous System, Humans, Magnetic Resonance Imaging, Retrospective Studies, Deep Learning, Multiparametric Magnetic Resonance Imaging
- Abstract
Background: Precise volumetric assessment of brain tumors is relevant for treatment planning and monitoring. However, manual segmentations are time-consuming and impeded by intra- and interrater variabilities., Purpose: To investigate the performance of a deep-learning model (DLM) to automatically detect and segment primary central nervous system lymphoma (PCNSL) on clinical MRI., Study Type: Retrospective., Population: Sixty-nine scans (at initial and/or follow-up imaging) from 43 patients with PCNSL referred for clinical MRI tumor assessment., Field Strength/sequence: T
1 -/T2 -weighted, T1 -weighted contrast-enhanced (T1 CE), and FLAIR at 1.0, 1.5, and 3.0T from different vendors and study centers., Assessment: Fully automated voxelwise segmentation of tumor components was performed using a 3D convolutional neural network (DeepMedic) trained on gliomas (n = 220). DLM segmentations were compared to manual segmentations performed in a 3D voxelwise manner by two readers (radiologist and neurosurgeon; consensus reading) from T1 CE and FLAIR, which served as the reference standard., Statistical Tests: Dice similarity coefficient (DSC) for comparison of spatial overlap with the reference standard, Pearson's correlation coefficient (r) to assess the relationship between volumetric measurements of segmentations, and Wilcoxon rank-sum test for comparison of DSCs obtained in initial and follow-up imaging., Results: The DLM detected 66 of 69 PCNSL, representing a sensitivity of 95.7%. Compared to the reference standard, DLM achieved good spatial overlap for total tumor volume (TTV, union of tumor volume in T1 CE and FLAIR; average size 77.16 ± 62.4 cm3 , median DSC: 0.76) and tumor core (contrast enhancing tumor in T1 CE; average size: 11.67 ± 13.88 cm3 , median DSC: 0.73). High volumetric correlation between automated and manual segmentations was observed (TTV: r = 0.88, P < 0.0001; core: r = 0.86, P < 0.0001). Performance of automated segmentations was comparable between pretreatment and follow-up scans without significant differences (TTV: P = 0.242, core: P = 0.177)., Data Conclusion: In clinical MRI scans, a DLM initially trained on gliomas provides segmentation of PCNSL comparable to manual segmentation, despite its complex and multifaceted appearance. Segmentation performance was high in both initial and follow-up scans, suggesting its potential for application in longitudinal tumor imaging., Level of Evidence: 3 TECHNICAL EFFICACY STAGE: 2., (© 2020 The Authors. Journal of Magnetic Resonance Imaging published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.)- Published
- 2021
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224. Are left atrial diverticula and left-sided septal pouches relevant additional findings in cardiac CT? Correlation between left atrial outpouching structures and ischemic brain alterations.
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Celik E, Pennig L, Laukamp KR, Hammes J, Maintz D, Kabbasch C, Abdullayev N, Bunck AC, Achenbach T, Caldeira L, and Hickethier T
- Subjects
- Brain diagnostic imaging, Heart Atria diagnostic imaging, Humans, Retrospective Studies, Risk Factors, Tomography, X-Ray Computed, Atrial Fibrillation, Diverticulum diagnostic imaging, Diverticulum epidemiology
- Abstract
Purpose: To evaluate the correlation between left atrial diverticula (LAD) and left-sided septal pouches (LSSP) with ischemic brain alterations in MRI., Methods: A retrospective analysis of 174 patients who received both, a dedicated cardiac CT angiography (CCTA) and a brain MRI examination was performed. Two radiologists independently reviewed all examinations for the presence of LAD and LSSP as well as ischemic alterations of the brain. Subsequently, the correlation between these cardiac and cerebral findings as well as to other potentially related risk factors was assessed., Results: 71 LAD (total prevalence 41%) and 65 LSSP (total prevalence 37%) were identified in 174 patients. Combined prevalence was 10%. Ischemic brain alterations were found in patients with a LAD in 42.3% (30/71) and with a LSSP in 64.6% (42/65). Patients without any anatomical variant in the left atrium showed ischemic brain alterations in 39.4% (26/66). The presence of a LSSP was associated with an increased risk for ischemic brain alterations in multivariate logistic regression analysis after adjusting for other risk factors (OR = 3.57, 95% CI = 0.51-2.09, p < .01)., Conclusion: In our study cohort LAD and LSSP are highly prevalent anatomical structures within the left atrium. Patients with LSSP showed an approximated 3.5-fold higher probability for ischemic brain alterations. Therefore, LSSP should be considered as a potential risk factor for cardioembolic strokes and its presence should be stated in cardiac CT reports., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2020
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225. Fusion zone microstructure image dataset of the flux-cored and shielded metal arc welding processes.
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Lagares ML Jr, Catão Silva G, and Caldeira L
- Abstract
This paper presents high quality (2048 × 1532 pixels) Light Microscope steel images sampled from the welding fusion zone. The microstructure images were acquired from the Design of Experiments (2
2 full factorial design) planned to compare two different arc welding processes at two different arc welding energies [1]. The 400 raw images appear as they were captured by the microscope and they are categorized into four groups: that acquired from the Flux Cored Arc Welding process and that acquired from the Shielded Metal Arc Welding process; both of them run for high and low levels of arc energy. For the Flux Cored Arc Welding process, ASME SFA 5.20 E71T-5C(M) tubular wire was used, with a nominal diameter of 1.2 mm. For the Shielded Metal Arc Welding process, AWS E7018 coated electrodes were used, with nominal diameters of 3.25 mm (for the low energy level) and 5.00 mm (for the high energy level). The deposition of the beads was run on AISI 1010 steel plates in the flat position (bead-on-plate). Different proportions of primary grain boundary ferrite; polygonal ferrite; acicular ferrite; nonaligned side-plate ferrite and aligned side-plate ferrite can be observed in each image. This image dataset is ready to visual and automatic microstructure recognition and quantification. It can be a useful resource for computational intelligence research teams, e.g. [2], by offering images for handling as filtering, feature extraction, training, validation and testing in pattern recognition and machine learning techniques., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article., (© 2020 The Author(s).)- Published
- 2020
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226. Artificial intelligence abstracts from the European Congress of Radiology: analysis of topics and compliance with the STARD for abstracts checklist.
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Dratsch T, Caldeira L, Maintz D, and Dos Santos DP
- Abstract
Objectives: To analyze all artificial intelligence abstracts presented at the European Congress of Radiology (ECR) 2019 with regard to their topics and their adherence to the Standards for Reporting Diagnostic accuracy studies (STARD) checklist., Methods: A total of 184 abstracts were analyzed with regard to adherence to the STARD criteria for abstracts as well as the reported modality, body region, pathology, and use cases., Results: Major topics of artificial intelligence abstracts were classification tasks in the abdomen, chest, and brain with CT being the most commonly used modality. Out of the 10 STARD for abstract criteria analyzed in the present study, on average, 5.32 (SD = 1.38) were reported by the 184 abstracts. Specifically, the highest adherence with STARD for abstracts was found for general interpretation of results of abstracts (100.0%, 184 of 184), clear study objectives (99.5%, 183 of 184), and estimates of diagnostic accuracy (96.2%, 177 of 184). The lowest STARD adherence was found for eligibility criteria for participants (9.2%, 17 of 184), type of study series (13.6%, 25 of 184), and implications for practice (20.7%, 44 of 184). There was no significant difference in the number of reported STARD criteria between abstracts accepted for oral presentation (M = 5.35, SD = 1.31) and abstracts accepted for the electronic poster session (M = 5.39, SD = 1.45) (p = .86)., Conclusions: The adherence with STARD for abstract was low, indicating that providing authors with the related checklist may increase the quality of abstracts.
- Published
- 2020
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227. Scatter Correction Based on GPU-Accelerated Full Monte Carlo Simulation for Brain PET/MRI.
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Ma B, Gaens M, Caldeira L, Bert J, Lohmann P, Tellmann L, Lerche C, Scheins J, Rota Kops E, Xu H, Lenz M, Pietrzyk U, and Shah NJ
- Subjects
- Algorithms, Brain Neoplasms diagnostic imaging, Equipment Design, Humans, Imaging, Three-Dimensional methods, Monte Carlo Method, Phantoms, Imaging, Brain diagnostic imaging, Magnetic Resonance Imaging methods, Positron-Emission Tomography methods
- Abstract
Accurate scatter correction is essential for qualitative and quantitative PET imaging. Until now, scatter correction based on Monte Carlo simulation (MCS) has been recognized as the most accurate method of scatter correction for PET. However, the major disadvantage of MCS is its long computational time, which makes it unfeasible for clinical usage. Meanwhile, single scatter simulation (SSS) is the most widely used method for scatter correction. Nevertheless, SSS has the disadvantage of limited robustness for dynamic measurements and for the measurement of large objects. In this work, a newly developed implementation of MCS using graphics processing unit (GPU) acceleration is employed, allowing full MCS-based scatter correction in clinical 3D brain PET imaging. Starting from the generation of annihilation photons to their detection in the simulated PET scanner, all relevant physical interactions and transport phenomena of the photons were simulated on GPUs. This resulted in an expected distribution of scattered events, which was subsequently used to correct the measured emission data. The accuracy of the approach was validated with simulations using GATE (Geant4 Application for Tomography Emission), and its performance was compared to SSS. The comparison of the computation time between a GPU and a single-threaded CPU showed an acceleration factor of 776 for a voxelized brain phantom study. The speedup of the MCS implemented on the GPU represents a major step toward the application of the more accurate MCS-based scatter correction for PET imaging in clinical routine.
- Published
- 2020
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228. Resolution modeling in projection space using a factorized multi-block detector response function for PET image reconstruction.
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Xu H, Lenz M, Caldeira L, Ma B, Pietrzyk U, Lerche C, Shah NJ, and Scheins J
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- Computer Simulation, Humans, Algorithms, Brain diagnostic imaging, Image Processing, Computer-Assisted methods, Phantoms, Imaging, Positron-Emission Tomography instrumentation, Positron-Emission Tomography methods
- Abstract
Positron emission tomography (PET) images usually suffer from limited resolution and statistical uncertainties. However, a technique known as resolution modeling (RM) can be used to improve image quality by accurately modeling the system's detection process within the iterative reconstruction. In this study, we present an accurate RM method in projection space based on a simulated multi-block detector response function (DRF) and evaluate it on the Siemens hybrid MR-BrainPET system. The DRF is obtained using GATE simulations that consider nearly all the possible annihilation photons from the field-of-view (FOV). Intrinsically, the multi-block DRF allows the block crosstalk to be modeled. The RM blurring kernel is further generated by factorizing the blurring matrix of one line-of-response (LOR) into two independent detector responses, which can then be addressed with the DRF. Such a kernel is shift-variant in 4D projection space without any distance or angle compression, and is integrated into the image reconstruction for the BrainPET insert with single instruction multiple data (SIMD) and multi-thread support. Evaluation of simulations and measured data demonstrate that the reconstruction with RM yields significantly improved resolutions and reduced mean squared error (MSE) values at different locations of the FOV, compared with reconstruction without RM. Furthermore, the shift-variant RM kernel models the varying blurring intensity for different LORs due to the depth-of-interaction (DOI) dependencies, thus avoiding severe edge artifacts in the images. Additionally, compared to RM in single-block mode, the multi-block mode shows significantly improved resolution and edge recovery at locations beyond 10 cm from the center of BrainPET insert in the transverse plane. However, the differences have been observed to be low for patient data between single-block and multi-block mode RM, due to the brain size and location as well as the geometry of the BrainPET insert. In conclusion, the RM method proposed in this study can yield better reconstructed images in terms of resolution and MSE value, compared to conventional reconstruction without RM.
- Published
- 2019
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229. Application of modern autoradiography to nuclear forensic analysis.
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Parsons-Davis T, Knight K, Fitzgerald M, Stone G, Caldeira L, Ramon C, and Kristo M
- Abstract
Modern autoradiography techniques based on phosphorimaging technology using image plates (IPs) and digital scanning can identify heterogeneities in activity distributions and reveal material properties, serving to inform subsequent analyses. Here, we have adopted these advantages for applications in nuclear forensics, the technical analysis of radioactive or nuclear materials found outside of legal control to provide data related to provenance, production history, and trafficking route for the materials. IP autoradiography is a relatively simple, non-destructive method for sample characterization that records an image reflecting the relative intensity of alpha and beta emissions from a two-dimensional surface. Such data are complementary to information gathered from radiochemical characterization via bulk counting techniques, and can guide the application of other spatially resolved techniques such as scanning electron microscopy (SEM) and secondary ion mass spectrometry (SIMS). IP autoradiography can image large 2-dimenstional areas (up to 20×40cm), with relatively low detection limits for actinides and other radioactive nuclides, and sensitivity to a wide dynamic range (10
5 ) of activity density in a single image. Distributions of radioactivity in nuclear materials can be generated with a spatial resolution of approximately 50μm using IP autoradiography and digital scanning. While the finest grain silver halide films still provide the best possible resolution (down to ∼10μm), IP autoradiography has distinct practical advantages such as shorter exposure times, no chemical post-processing, reusability, rapid plate scanning, and automated image digitization. Sample preparation requirements are minimal, and the analytical method does not consume or alter the sample. These advantages make IP autoradiography ideal for routine screening of nuclear materials, and for the identification of areas of interest for subsequent micro-characterization methods. In this paper we present a summary of our setup, as modified for nuclear forensic sample analysis and related research, and provide examples of data from select samples from the nuclear fuel cycle and historical nuclear test debris., (Copyright © 2018 Elsevier B.V. All rights reserved.)- Published
- 2018
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230. Abacavir usage patterns and hypersensitivity reactions in the EuroSIDA cohort.
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Roen A, Laut K, Pelchen-Matthews A, Borodulina E, Caldeira L, Clarke A, Clotet B, d'Arminio Monforte A, Fätkenheuer G, Gatell Artigas JM, Karpov I, Kuznetsova A, Kyselyova G, Mozer-Lisewska I, Mulcahy F, Ragone L, Scherrer A, Uzdaviniene V, Vandekerckhove L, Vannappagari V, Ostergaard L, and Mocroft A
- Subjects
- Adult, Cohort Studies, Drug Hypersensitivity etiology, Drug Utilization, Europe epidemiology, Female, Humans, Incidence, Longitudinal Studies, Male, Middle Aged, Poisson Distribution, Anti-HIV Agents adverse effects, Dideoxynucleosides adverse effects, Drug Hypersensitivity epidemiology, HIV Infections drug therapy
- Abstract
Objectives: Five to eight per cent of HIV-positive individuals initiating abacavir (ABC) experience potentially fatal hypersensitivity reactions (HSRs). We sought to describe the proportion of individuals initiating ABC and to describe the incidence and factors associated with HSR among those prescribed ABC., Methods: We calculated the proportion of EuroSIDA individuals receiving ABC-based combination antiretroviral therapy (cART) among those receiving cART after 1 January 2009. Poisson regression was used to identify demographic, and current clinical and laboratory factors associated with ABC utilization and discontinuation., Results: Between 2009 and 2016, of 10 076 individuals receiving cART, 3472 (34%) had ever received ABC-based cART. Temporal trends of ABC utilization were also heterogeneous, with 28% using ABC in 2009, dropping to 26% in 2010 and increasing to 31% in 2016, and varied across regions and over time. Poisson models showed lower ABC utilization in older individuals, and in those with higher CD4 cell counts, higher cART lines, and prior AIDS. Higher ABC utilization was associated with higher HIV RNA and poor renal function, and was more common in Central-East and Eastern Europe and lowest during 2014. During 779 person-years of follow-up (PYFU) in 2139 individuals starting ABC after 1 January 2009, 113 discontinued ABC within 6 weeks of initiation for any reason [incidence rate (IR) 14.5 (95% confidence interval (CI) 12.1, 17.5) per 100 PYFU], 13 because of reported HSR [IR 0.3 (95% CI 0.1, 1.0) per 100 PYFU] and 35 because of reported HSR/any toxicity [IR 4.5 (95% CI 3.2, 6.3) per 100 PYFU]. There were no factors significantly associated with ABC discontinuation because of reported HSR/any toxicity., Conclusions: ABC remains commonly used across Europe and the incidence of discontinuation because of reported HSR was low in our study population., (© 2017 British HIV Association.)
- Published
- 2018
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231. PET attenuation correction for rigid MR Tx/Rx coils from 176 Lu background activity.
- Author
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Lerche CW, Kaltsas T, Caldeira L, Scheins J, Rota Kops E, Tellmann L, Pietrzyk U, Herzog H, and Shah NJ
- Subjects
- Humans, Brain diagnostic imaging, Brain metabolism, Lutetium metabolism, Magnetic Resonance Imaging methods, Phantoms, Imaging, Positron-Emission Tomography methods, Radioisotopes metabolism
- Abstract
One challenge for PET-MR hybrid imaging is the correction for attenuation of the 511 keV annihilation radiation by the required RF transmit and/or RF receive coils. Although there are strategies for building PET transparent Tx/Rx coils, such optimised coils still cause significant attenuation of the annihilation radiation leading to artefacts and biases in the reconstructed activity concentrations. We present a straightforward method to measure the attenuation of Tx/Rx coils in simultaneous MR-PET imaging based on the natural
176 Lu background contained in the scintillator of the PET detector without the requirement of an external CT scanner or PET scanner with transmission source. The method was evaluated on a prototype 3T MR-BrainPET produced by Siemens Healthcare GmbH, both with phantom studies and with true emission images from patient/volunteer examinations. Furthermore, the count rate stability of the PET scanner and the x-ray properties of the Tx/Rx head coil were investigated. Even without energy extrapolation from the two dominant γ energies of176 Lu to 511 keV, the presented method for attenuation correction, based on the measurement of176 Lu background attenuation, shows slightly better performance than the coil attenuation correction currently used. The coil attenuation correction currently used is based on an external transmission scan with rotating68 Ge sources acquired on a Siemens ECAT HR + PET scanner. However, the main advantage of the presented approach is its straightforwardness and ready availability without the need for additional accessories.- Published
- 2018
- Full Text
- View/download PDF
232. Serum Albumin as a Prognostic Marker for Serious Non-AIDS Endpoints in the Strategic Timing of Antiretroviral Treatment (START) Study.
- Author
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Ronit A, Sharma S, Baker JV, Mngqibisa R, Delory T, Caldeira L, Ndembi N, Lundgren JD, and Phillips AN
- Subjects
- Adult, Aged, Female, Follow-Up Studies, Hospitalization, Humans, Male, Middle Aged, Prognosis, Risk Assessment, Biomarkers blood, HIV Infections complications, Noncommunicable Diseases epidemiology, Serum Albumin, Human analysis
- Abstract
Background: Serum albumin may be used to stratify human immunodeficiency virus (HIV)-infected persons with high CD4 count according to their risk of serious non-AIDS endpoints., Methods: Cox proportional hazards models were used to analyze the risk of serious non-AIDS events in the Strategic Timing of Antiretroviral Treatment (START) study (NCT00867048) with serum albumin as a fixed and time-updated predictor. Models with exclusion of events during initial follow-up years were built to assess the ability of serum albumin to predict beyond shorter periods of time. Secondarily, we considered hospitalizations and AIDS events., Results: Among 4576 participants, 71 developed a serious non-AIDS event, 788 were hospitalized, and 63 experienced an AIDS event. After adjusting for a range of variables associated with hypoalbuminemia, higher baseline serum albumin (per 1 g/dL) was associated with a decreased risk of serious non-AIDS events (hazard ratio, 0.37 [95% confidence interval, .20-.71]; P = .002). Similar results were obtained in a time-updated model, after controlling for interleukin 6, and after excluding initial follow-up years. Serum albumin was independently associated with hospitalization but not with risk of AIDS., Conclusions: A low serum albumin level is a predictor for short- and long-term serious non-AIDS events, and may be a useful marker of risk of noncommunicable diseases, particularly in resource-limited settings., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)
- Published
- 2018
- Full Text
- View/download PDF
233. Reversal of ocean acidification enhances net coral reef calcification.
- Author
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Albright R, Caldeira L, Hosfelt J, Kwiatkowski L, Maclaren JK, Mason BM, Nebuchina Y, Ninokawa A, Pongratz J, Ricke KL, Rivlin T, Schneider K, Sesboüé M, Shamberger K, Silverman J, Wolfe K, Zhu K, and Caldeira K
- Subjects
- Animals, Anthozoa chemistry, Calcium Carbonate metabolism, Carbon Cycle, Coloring Agents, Hydrogen-Ion Concentration, Oceans and Seas, Temperature, Anthozoa metabolism, Calcification, Physiologic, Coral Reefs, Seawater chemistry
- Abstract
Approximately one-quarter of the anthropogenic carbon dioxide released into the atmosphere each year is absorbed by the global oceans, causing measurable declines in surface ocean pH, carbonate ion concentration ([CO3(2-)]), and saturation state of carbonate minerals (Ω). This process, referred to as ocean acidification, represents a major threat to marine ecosystems, in particular marine calcifiers such as oysters, crabs, and corals. Laboratory and field studies have shown that calcification rates of many organisms decrease with declining pH, [CO3(2-)], and Ω. Coral reefs are widely regarded as one of the most vulnerable marine ecosystems to ocean acidification, in part because the very architecture of the ecosystem is reliant on carbonate-secreting organisms. Acidification-induced reductions in calcification are projected to shift coral reefs from a state of net accretion to one of net dissolution this century. While retrospective studies show large-scale declines in coral, and community, calcification over recent decades, determining the contribution of ocean acidification to these changes is difficult, if not impossible, owing to the confounding effects of other environmental factors such as temperature. Here we quantify the net calcification response of a coral reef flat to alkalinity enrichment, and show that, when ocean chemistry is restored closer to pre-industrial conditions, net community calcification increases. In providing results from the first seawater chemistry manipulation experiment of a natural coral reef community, we provide evidence that net community calcification is depressed compared with values expected for pre-industrial conditions, indicating that ocean acidification may already be impairing coral reef growth.
- Published
- 2016
- Full Text
- View/download PDF
234. Simultaneous acquisition of dynamic PET-MRI: arterial input function using DSC-MRI and [18F]-FET.
- Author
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Caldeira L, Yun SD, da Silva N, Filss C, Scheins J, Telmann L, Herzog H, and Shah J
- Published
- 2015
- Full Text
- View/download PDF
235. Attenuation correction for hybrid MR/PET scanners: a comparison study.
- Author
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Rota Kops E, Ribeiro AS, Caldeira L, Hautzel H, Lukas M, Antoch G, Lerche C, and Shah J
- Published
- 2015
- Full Text
- View/download PDF
236. Automatic derivation of an MR-PET image-based input function for quantification of 18F-FET.
- Author
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da Silva NA, Caldeira L, Herzog H, Tellmann L, Filss C, Langen KJ, and Shah J
- Published
- 2015
- Full Text
- View/download PDF
237. Hypovitaminosis D in HIV-infected patients in Lisbon: a link with antiretroviral treatment.
- Author
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Boura M, Sutre AF, Badura R, Zagalo A, Afonso C, Caldeira L, and Valadas E
- Abstract
Introduction: Recent data indicates that low vitamin D (25(OH)D) levels can lead to a worst prognosis in HIV-infected individuals, even in those on successful antiretroviral therapy (ART) [1]. Portugal is the European country that has the largest average sun exposure time but prevalence of hypovitaminosis D is mostly unknown. Our aim was to determine the prevalence of hypovitaminosis D in HIV patients in Lisbon and the possible association with ART., Methods: From 2012 to January 2014, plasma samples from 518 HIV-infected patients were collected to 25(OH)D levels determination. Data on demographic features (age, ethnicity, country of origin) and clinical/laboratory parameters were collected from clinical files (HIV subtype, CD4+ cell count, CD4+ nadir, viral load (VL), HBV/HCV co-infection and ART). 25(OH)D status was defined as: deficiency <20 ng/mL, insufficiency 20-30 ng/mL, optimal >30 ng/mL., Results: Median age was 46 years old (±11); 62.0% (321/518) were male; 81.3% (421/518) were Caucasian and 78.6% (407/518) were Portuguese. Most patients (96.1%; 498/518), were HIV-1 infected, 22.9% (114/498) and 4.0% (20/498) of them were HCV and/or HBV co-infected, respectively. Mean CD4+ cell count was 648 cells/µL (±333) and nadir was 219 cells/µL (±179). On treated patients VL was <40 HIV RNA/mL in 86.7% (417/481). The median levels of 25(OH)D was 20.0 ng/mL (range 4.1-99.7) and we found differences between values observed during Winter (median 16.7 ng/mL) and Summer (median 24.9 ng/mL) (p<0.0001). Low 25(OH)D levels were not correlated to ethnicity (p=0.066). 25(OH)D level was <30 ng/mL in 80.1% (415/518) of the patients, from which 30.9% (160/518) and 49.2% (255/518) had insufficiency and deficiency levels, respectively. Most (92.9%; 481/518) were on ART: regimens containing PI (47.5%), NNRTI (40.3%; 41.3% on NVP and 58.7% on EFV), II (1.2%), PI+NNRTI (3.9%). Comparing the 25(OH)D level along the different ART regimens (PI vs NVP; PI vs EFV; PI vs no ART) there were differences between PI and EFV (p=0.044)., Conclusions: In this study, 80.1% of the HIV-infected patients had hypovitaminosis D and ART regimens with EFV were more often associated with low 25(OH)D levels. Understanding the impact of the different antiretroviral drugs on 25(OH)D status could help to decide in clinical practice whether 25(OH)D supplementation or drug switch are the best options for each patient.
- Published
- 2014
- Full Text
- View/download PDF
238. Dynamic analysis of MR-PET data on brain tumors.
- Author
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Morgado A, Caldeira L, da Silva N, Filss C, Matela N, Langen KJ, and Shah NJ
- Published
- 2014
- Full Text
- View/download PDF
239. PET motion correction using PRESTO with ITK motion estimation.
- Author
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Botelho M, Caldeira L, Scheins J, Matela N, Kops ER, and Shah NJ
- Published
- 2014
- Full Text
- View/download PDF
240. Optimisation of PET framing sequences.
- Author
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Patrício M and Caldeira L
- Published
- 2014
- Full Text
- View/download PDF
241. Effects of regularisation priors on dynamic PET Data.
- Author
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Caldeira L, Scheins J, da Silva N, Gaens M, and Shah NJ
- Published
- 2014
- Full Text
- View/download PDF
242. High-resolution, quantitative 3D PET image reconstruction for the Siemens hybrid 3T MR/BrainPET scanner using the PET reconstruction software toolkit (PRESTO).
- Author
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Scheins J, Weirich C, Caldeira L, Lohmann P, Kops ER, Tellmann L, Gaens M, Herzog H, Pietrzyk U, and Shah NJ
- Published
- 2014
- Full Text
- View/download PDF
243. Effects of magnetic fields of up to 9.4 T on resolution and contrast of PET images as measured with an MR-BrainPET.
- Author
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Shah NJ, Herzog H, Weirich C, Tellmann L, Kaffanke J, Caldeira L, Kops ER, Qaim SM, Coenen HH, and Iida H
- Subjects
- Contrast Media, Electrons, Fluorine Radioisotopes, Gallium Radioisotopes, Humans, Iodine Radioisotopes, Phantoms, Imaging, Brain diagnostic imaging, Magnetic Fields, Magnetic Resonance Imaging, Positron-Emission Tomography
- Abstract
Simultaneous, hybrid MR-PET is expected to improve PET image resolution in the plane perpendicular to the static magnetic field of the scanner. Previous papers have reported this either by simulation or experiment with simple sources and detector arrangements. Here, we extend those studies using a realistic brain phantom in a recently installed MR-PET system comprising a 9.4 T MRI-scanner and an APD-based BrainPET insert in the magnet bore. Point and line sources and a 3D brain phantom were filled with 18F (low-energy positron emitter), 68Ga (medium energy positron emitter) or 120I, a non-standard positron emitter (high positron energies of up to 4.6 MeV). Using the BrainPET insert, emission scans of the phantoms were recorded at different positions inside and outside the magnet bore such that the magnetic field was 0 T, 3 T, 7 T or 9.4 T. Brain phantom images, with the 'grey matter' compartment filled with 18F, showed no obvious resolution improvement with increasing field. This is confirmed by practically unchanged transaxial FWHM and 'grey/white matter' ratio values between at 0T and 9.4T. Field-dependent improvements in the resolution and contrast of transaxial PET images were clearly evident when the brain phantom was filled with 68Ga or 120I. The grey/white matter ratio increased by 7.3% and 16.3%, respectively. The greater reduction of the FWTM compared to FWHM in 68Ga or 120I line-spread images was in agreement with the improved contrast of 68Ga or 120I images. Notwithstanding elongations seen in the z-direction of 68Ga or 120I point source images acquired in foam, brain phantom images show no comparable extension. Our experimental study confirms that integrated MR-PET delivers improved PET image resolution and contrast for medium- and high-energy positron emitters even though the positron range is reduced only in directions perpendicular to the magnetic field.
- Published
- 2014
- Full Text
- View/download PDF
244. [Cognitive decline of medicamentous etiology].
- Author
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Caldeira L, Varanda S, Machado A, Ferreira C, and Carneiro G
- Subjects
- Aged, Female, Humans, Cognition Disorders chemically induced, Polypharmacy
- Abstract
In the elderly there is a high risk of inappropriate medication and adverse effects of polypharmacy. A 68 year-old female patient resorted to the Emergency Room for suspected stroke. According to the husband, in the six months prior to admission, she became progressively disorientated and dependent. She had resorted to various appointments from different specialties and was polymedicated. It was impossible to clarify the exact dosage. On neurological examination she presented disturbance in attention and memory, disorientation, constructional apraxia, myoclonus and gait imbalance. After the suspension of all chronic medication, she showed gradual improvement. By the time of discharge, her neurological examination was completely normal. Iatrogenic effect of drugs as a cause of reversible dementia should be considered. All patients, particularly the elderly and their caregivers, should be suitably informed about the drugs that are prescribed and the dosages used. Using the biopsychosocial model could prevent inappropriate polypharmacy and iatrogeny.
- Published
- 2014
245. Critical analysis about solutions and models of solar shades in non-residential buildings from tropical regions.
- Author
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Castañon JA, Caldeira LF, Gervásio MF, and Brum FM
- Subjects
- Conservation of Energy Resources, Humans, Facility Design and Construction, Sunlight, Tropical Climate
- Abstract
Whereas the non-residential buildings consume a significant percentage of the total energy produced by the city, is important that these buildings have for such consumption is reduced or consumed in a conscious way. To do so, using concepts of energy efficiency, this work is to explain passive strategies with the use of flexible solar shades that help to get a favorable outcome with respect to the performance of the building right in the initial stages of planning and design. Once initial gains can be obtained and the architecture constants that value at the same time provide better working conditions and indoor comfort.
- Published
- 2012
- Full Text
- View/download PDF
246. [Monitoring antibiotic consumption in the surgery and orthopaedics].
- Author
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Caldeira L, Teixeira I, Vieira I, Batel Marques F, Santiago LM, Rodrigues V, Fonseca A, Varanda J, Bicó A, Vasconcelos C, Polónia J, Brochado J, Faria V, Mota A, Ramalheira E, Capão Filipe M, Marques MS, Lopes Martins M, Carmo E, Martins F, Contente H, Lobo M, Gloria P, Pereira L, and Faria D
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Bacterial Infections prevention & control, Child, Child, Preschool, Cross Infection prevention & control, Female, Humans, Longitudinal Studies, Male, Middle Aged, Pilot Projects, Surgery Department, Hospital statistics & numerical data, Anti-Bacterial Agents economics, Anti-Bacterial Agents therapeutic use, Bacterial Infections drug therapy, Drug Utilization Review, Orthopedic Procedures statistics & numerical data, Surgical Wound Infection prevention & control
- Abstract
Monitoring antibiotic consumption is a valuable tool which has been increasingly used in the last years due to the current concern with the emergence of resistant microbial strains. The present study aimed at monitoring antibiotic consumption, evaluating the economic impact of hospital antibiotic prescription and assessing the relationship between the prescribed antibiotics and the indications for either prophylactic or therapeutic use. This was a longitudinal pilot-study for which data were collected in six privately managed public hospital units during the month of May 2004, with a resulting sample of 1,122 admitted patients. We observed a prescription incidence rate of 76.9%, corresponding to a total of 1,154 dispensed antimicrobials, with a mean 71.2% of these antimicrobials being dispensed for the prophylaxis of surgical site infection (SSI). The mean cost of antibiotic courses was higher in cases of "suspected infection" (9.09 euro) or "confirmed infection" (8.74 euro) and lower in cases of "prophylaxis" (5.67 euro), a finding which is explained by the shorter mean duration of the later. There was a considerable variation among the different hospital units regarding the type of antibiotic compound that was used for SSI prophylaxis, with a mean duration of antibiotic use of 2.61 days for this indication and about half of the prophylactic regimens lasting longer than 24 hours, a fact that suggests an insufficient observation of the current recommendations for antibiotic use in SSI prophylaxis. This finding indicates the need for an investigation on the actual existence of local recommendations for SSI prophylaxis in individual hospital units and also for the evaluation of the compliance of practicing surgeons with eventually existing recommendations.
- Published
- 2006
247. Evaluation of a nested PCR for detection of Pneumocystis carinii in serum from immunocompromised patients.
- Author
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Matos O, Lundgren B, Caldeira L, Mansinho K, Aguiar P, Forte M, and Antunes F
- Subjects
- AIDS-Related Opportunistic Infections microbiology, Evaluation Studies as Topic, Fungemia diagnosis, HIV Seronegativity, Humans, Lung microbiology, Pneumocystis genetics, Pneumonia, Pneumocystis microbiology, Predictive Value of Tests, Sensitivity and Specificity, AIDS-Related Opportunistic Infections diagnosis, DNA, Fungal blood, Immunocompromised Host, Pneumocystis isolation & purification, Pneumonia, Pneumocystis diagnosis, Polymerase Chain Reaction methods
- Published
- 1999
248. [Emphysematous cholecystitis].
- Author
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Freitas L, Do Carmo G, Caldeira L, Farto e Abreu J, Lélis M, and Doroana M
- Subjects
- Aged, Female, Humans, Cholecystitis diagnosis
- Abstract
Emphysematous cholecystitis (EC) is a rare and dramatic disease that requires prompt therapeutic procedures. The authors report a case of a 70-year-old-woman, admitted to the Intensive Care Unit for Infectious Diseases of the Santa Maria Hospital, with the diagnosis of EC. The literature on EC is also reviewed.
- Published
- 1992
249. [Febrile coma and disseminated intravascular coagulation following heat stroke].
- Author
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Lélis M, do Carmo G, Caldeira L, Abreu J, Freitas L, and Doroana M
- Subjects
- Adult, Coma complications, Disseminated Intravascular Coagulation complications, Female, Humans, Coma etiology, Disseminated Intravascular Coagulation etiology, Heat Exhaustion complications
- Abstract
A clinical case that occurred in a 42 years old female and which fulfils the diagnostic criteria for the entity described as Heat Stroke is presented. In this case, besides the usual manifestations of hyperpyrexia without sweating along with consciousness disorders, features of consumptive coagulopathy, rhabdomyolysis and well marked laboratory liver dysfunction have also been found. The severity of this situation and its less common occurrence in temperate climates, together with the uncertainty in establishing the diagnosis, namely when infection is suspected--in the present case the initial diagnosis was Sepsis, which led to patient's admission in an infectious diseases intensive care unit--motivate the authors to make this report. Furthermore, they consider this case to be a good example of the varied clinical and laboratory manifestations and possible severe complications that Heat Stroke may display.
- Published
- 1992
250. Translocation (4;14) and concomitant inv(14) in a basal cell carcinoma.
- Author
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Kawasaki RS, Caldeira LF, André FS, Gasques JA, Castilho WH, Bozola AR, Thomé JA, and Tajara EH
- Subjects
- Chromosome Inversion, Female, Humans, Karyotyping, Middle Aged, Translocation, Genetic, Tumor Cells, Cultured, Carcinoma, Basal Cell genetics, Chromosome Aberrations, Chromosomes, Human, Pair 14, Chromosomes, Human, Pair 4, Nose Neoplasms genetics
- Abstract
Chromosome analysis of short-term cultures from a basal cell carcinoma was performed. The analyzed karyotypes showed a pseudodiploid clone characterized by a der(4)t(4;14) (p14;p11) and a concomitant inversion of the same chromosome 4 involved in the t(4;14) with the breakpoints at p14 and q25.
- Published
- 1991
- Full Text
- View/download PDF
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