Computed tomography attenuation in differential diagnosis of transudative and exudative pleural effusions.

OBJECTIVE: Pleural effusion is a common medical problem. It is important to decide whether the pleural fluid is a transudate or an exudate. This study aims to measure the attenuation values of pleural effusions on thorax computed tomography and to investigate the efficacy of this measurement in the diagnostic separation of transudates and exudates. MATERIALS AND METHODS: 380 cases who underwent thoracentesis and thorax computed tomography with pleural effusion were classified as exudates or transudates based on Light's criteria. Attenuation measurements in Hounsfield units were performed through the examination of thorax computed tomography images. RESULTS: 380 patients were enrolled (39 % women), the mean age was 69.9 ± 15.2 years. 125 (33 %) were transudates whereas 255 (67 %) were exudates. The attenuation values of exudates were significantly higher than transudates (15.1 ± 5.1 and 5.0 ± 3.4) (p < 0.001). When the attenuation cut-off was set at ≥ 10 HU, exudates were differentiated from transudates at high efficiency (sensitivity is 89.7 %, specificity is 94.4 %, PPV is 97 %, NPV is 81.9 %). When the cut-off value was accepted as < 6 HU, transudates were differentiated from exudates with 97.2 % specificity. CONCLUSION: The attenuation measurements of pleural fluids can be considered as an efficacious way of differentiating exudative and transudative pleural effusions.

TEMPy: a toolkit for the modeling of weighted tissue equivalent material in diagnostic imaging.

Objective.Accurate simulation of human tissues is imperative for advancements in diagnostic imaging, particularly in the fields of dosimetry and image quality evaluation. Developing Tissue Equivalent Materials (TEMs) with radiological characteristics akin to those of human tissues is essential for ensuring the reliability and relevance of imaging studies. This study presents the development of a mathematical model and a new toolkit (TEMPy) for obtaining the best composition of materials that mimic the radiological characteristics of human tissues. The model and the toolkit are described, along with an example showcasing its application to obtain desired TEMs.Approach.The methodology consisted of fitting volume fractions of the components of TEM in order to determine its linear attenuation coefficient as close as possible to the linear attenuation coefficient of the reference material. The fitting procedure adopted a modified Least Square Method including a weight function. This function reflects the contribution of the x-ray spectra in the suitable energy range of interest. TEMPy can also be used to estimate the effective atomic number and electron density of the resulting TEM.Main results.TEMPy was used to obtain the chemical composition of materials equivalent to water and soft tissue, in the energy range used in x-ray imaging (10 -150 keV) and for breast tissue using the energy range (5-40 keV). The maximum relative difference between the linear attenuation coefficients of the developed and reference materials was ±5% in the considered energy ranges.Significance.TEMPy facilitates the formulation of TEMs with radiological properties closely mimicking those of real tissues, aiding in the preparation of physical anthropomorphic or geometric phantoms for various applications. The toolkit is freely available to interested readers.

Association between hepatic steatosis and fibrosis and arthritis among US adults: A population-based study.

BACKGROUND: Lipid metabolism factors may play a role in the development of arthritis and hepatic steatosis and fibrosis. The aim of this study was to explore the potential association between arthritis and hepatic steatosis and liver fibrosis. MATERIALS AND METHODS: The nationally representative sample from the National Health and Nutrition Examination Survey was analyzed, with data on arthritis diagnosis, subtype, and liver status obtained. Liver status was assessed using transient elastography. Hepatic steatosis was defined as a Controlled Attenuation Parameter (CAP) score ≥263 dB/m, and liver fibrosis status was defined as F0‒F4. Logistic regression models and subgroup analyses stratified by sex were used to evaluate the associations. Smooth curve fitting was used to describe the associations. RESULTS: The present study of 6,840 adults aged 20 years or older found a significant positive correlation between arthritis and CAP in multivariate logistic regression analysis (ß = 0.003, 95 % CI 0.001 to 0.0041, p < 0.001). Participants with arthritis had a higher risk of hepatic steatosis (OR = 1.248, 95 % CI 1.036 to 1.504, p = 0.020), particularly those with osteoarthritis or degenerative arthritis, but not rheumatoid arthritis (p = 0.847). The positive correlation was maintained in females (ß = 0.004, 95 % CI 0.002 to 0.006, p < 0.001), but not in males. There was no significant relationship between arthritis and liver fibrosis (p = 0.508). CONCLUSION: This study indicates that there is a positive correlation between arthritis and hepatic steatosis, particularly in females. Nonetheless, there is no significant relationship between arthritis and the risk of liver fibrosis.

Attenuation photochemical potential of Pontal of Paranapanema river waters (Brazil) from agrochemicals: geographical and temporal assessment.

Knowledge of the environmental photochemical fate of pesticides is essential to assess their potential impacts. However, there are few studies in the literature focused on the photochemical attenuation of micropollutants in Brazilian rivers. In this context, this study characterized the surface waters of the Pontal of Paranapanema region (region which concentrates more than 80% of Brazilian sugarcane cultivations), in order to determine its photochemical attenuation potential against micropollutants in different seasons. Thus, the steady-state concentrations of the photochemically produced reactive intermediates (PPRIs) (hydroxyl radical, HO•; singlet oxygen, 1O2, and triplet-excited state chromophoric dissolved organic matter, 3CDOM*), formed in the rivers, were simulated by using the APEX model (Aquatic Photochemistry of Environmentally-occurring Xenobiotics), considering the sunlight irradiance, water chemistry, and depth. Based on our simulations, these concentrations vary between 0.35 × 10-15 and 4.52 × 10-14 mol L-1 for HO•, 1.3 × 10-15 and 1.2 × 10--14 mol L-1 for 3CDOM*, and 2.5 × 10-15 and 2.5 × 10-14 mol L-1 for 1O2. Finally, mathematical simulations were used for predicting persistence of pesticides atrazine (ATZ) and diuron (DIR) in Pontal of Paranapanema surface waters and the half-life times (t1/2) of the pollutants ranged from a few hours to one week.

Design and Study of Novel Composites Based on EPDM Rubber Containing Bismuth (III) Oxide and Graphene Nanoplatelets for Gamma Radiation Shielding.

The mechanical, thermal and gamma radiation attenuation properties of ethylene-propylene-diene monomer (EPDM)-based composites containing graphene nanoplatelets (GNs) and bismuth (III) oxide nanoparticles (B) were investigated. The use of polyethylene glycol (PEG) as a compatibilizer to improve the dispersion of the fillers was also investigated. The results showed that the combined use of these fillers resulted in a drastic increase in mechanical properties, reaching 123% and 83% of tensile strength and elongation at break, respectively, compared to those of EPDM. In contrast, the addition of PEG to composites containing EPDM GNs and B resulted in composites with lower values of mechanical properties compared to the EPDM/B/GN-based composite. However, the presence of PEG leads to obtaining a composite (EPDM/B/GNP) with a mass attenuation coefficient to gamma radiation (137Cs, 662 keV) superior to that composite without PEG. In addition, the composite EPDM, B and PEG exhibited an elongation at break 153% superior to unfilled EPDM. Moreover, the binary filler system consisting of 100 phr of bismuth (III) oxide and 10 phr of GN leads to reaching 61% of the linear damping coefficient of the EPDM composite compared to that value of the unfilled EPDM. The study of the morphology and the state of filler dispersion in the polymer matrix, obtained using scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively, provides a useful background for understanding the factors affecting the gamma radiation attenuation properties. Finally, the results also indicated that by adjusting the formulation, it is possible to tune the mechanical and thermal properties of EPDM composites reinforced with bismuth oxide and graphene nanoplatelets.

Association between hepatic steatosis and fibrosis and arthritis among US adults: A population-based study

Abstract Background: Lipid metabolism factors may play a role in the development of arthritis and hepatic steatosis and fibrosis. The aim of this study was to explore the potential association between arthritis and hepatic steatosis and liver fibrosis. Materials and methods: The nationally representative sample from the National Health and Nutrition Examination Survey was analyzed, with data on arthritis diagnosis, subtype, and liver status obtained. Liver status was assessed using transient elastography. Hepatic steatosis was defined as a Controlled Attenuation Parameter (CAP) score ≥263 dB/m, and liver fibrosis status was defined as F0‒F4. Logistic regression models and subgroup analyses stratified by sex were used to evaluate the associations. Smooth curve fitting was used to describe the associations. Results: The present study of 6,840 adults aged 20 years or older found a significant positive correlation between arthritis and CAP in multivariate logistic regression analysis (β = 0.003, 95 % CI 0.001 to 0.0041, p < 0.001). Participants with arthritis had a higher risk of hepatic steatosis (OR = 1.248, 95 % CI 1.036 to 1.504, p = 0.020), particularly those with osteoarthritis or degenerative arthritis, but not rheumatoid arthritis (p = 0.847). The positive correlation was maintained in females (β = 0.004, 95 % CI 0.002 to 0.006, p < 0.001), but not in males. There was no significant relationship between arthritis and liver fibrosis (p = 0.508). Conclusion: This study indicates that there is a positive correlation between arthritis and hepatic steatosis, particularly in females. Nonetheless, there is no significant relationship between arthritis and the risk of liver fibrosis.

Synthetic Attenuation Correction Maps for SPECT Imaging Using Deep Learning: A Study on Myocardial Perfusion Imaging.

(1) Background: The CT-based attenuation correction of SPECT images is essential for obtaining accurate quantitative images in cardiovascular imaging. However, there are still many SPECT cameras without associated CT scanners throughout the world, especially in developing countries. Performing additional CT scans implies troublesome planning logistics and larger radiation doses for patients, making it a suboptimal solution. Deep learning (DL) offers a revolutionary way to generate complementary images for individual patients at a large scale. Hence, we aimed to generate linear attenuation coefficient maps from SPECT emission images reconstructed without attenuation correction using deep learning. (2) Methods: A total of 384 SPECT myocardial perfusion studies that used 99mTc-sestamibi were included. A DL model based on a 2D U-Net architecture was trained using information from 312 patients. The quality of the generated synthetic attenuation correction maps (ACMs) and reconstructed emission values were evaluated using three metrics and compared to standard-of-care data using Bland-Altman plots. Finally, a quantitative evaluation of myocardial uptake was performed, followed by a semi-quantitative evaluation of myocardial perfusion. (3) Results: In a test set of 66 test patients, the ACM quality metrics were MSSIM = 0.97 ± 0.001 and NMAE = 3.08 ± 1.26 (%), and the reconstructed emission quality metrics were MSSIM = 0.99 ± 0.003 and NMAE = 0.23 ± 0.13 (%). The 95% limits of agreement (LoAs) at the voxel level for reconstructed SPECT images were: [-9.04; 9.00]%, and for the segment level, they were [-11; 10]%. The 95% LoAs for the Summed Stress Score values between the images reconstructed were [-2.8, 3.0]. When global perfusion scores were assessed, only 2 out of 66 patients showed changes in perfusion categories. (4) Conclusion: Deep learning can generate accurate attenuation correction maps from non-attenuation-corrected cardiac SPECT images. These high-quality attenuation maps are suitable for attenuation correction in myocardial perfusion SPECT imaging and could obviate the need for additional imaging in standalone SPECT scanners.

Low-Normal Thyroid Function Is Not Associated with Either Non-Alcoholic Fatty Liver Disease or with Metabolic Dysfunction-Associated Fatty Liver Disease.

BACKGROUND: The association of low-normal thyroid function (LNTF) with non-alcoholic fatty liver disease (NAFLD) or metabolic dysfunction-associated fatty liver disease (MAFLD) is controversial; thus, the aim of this study is to determine this association. METHODS: NAFLD was evaluated by controlled attenuation parameter of transient elastography. Patients were classified by MAFLD criteria. LNTF was defined as TSH levels of 2.5 to 4.5 mIU/L and were divided into three different cut-off points (>4.5 to 5.0, >3.1, and >2.5 mIU/L). Associations between LNTF, NAFLD, and MAFLD were evaluated by univariate and multivariate logistic regression analyses. RESULTS: A total of 3697 patients were included; 59% (n = 2179) were male, and median age and body mass index were 48 (43-55) years and 25.9 (23.6-28.5) kg/m2, respectively, and 44% (n = 1632) were diagnosed with NAFLD. THS levels of 2.5 and 3.1 showed significant associations with the presence of NAFLD and MAFLD; however, LNTF did not show an independent association with the presence of NAFLD or MAFLD in multivariate analysis. According to different cut-off points, patients with LNTF presented similar risks for NAFLD as the general population. CONCLUSION: LNTF is not associated with NAFLD or MAFLD. Patients with high LNTF are equally at risk for NAFLD as the general population.

Ultrasound attenuation imaging: a reproducible alternative for the noninvasive quantitative assessment of hepatic steatosis in children.

BACKGROUND: Pediatric hepatic steatosis is a global public health concern, as an increasing number of children are affected by this condition. Liver biopsy is the gold standard diagnostic method; however, this procedure is invasive. Magnetic resonance imaging (MRI)-derived proton density fat fraction has been accepted as an alternative to biopsy. However, this method is limited by cost and availability. Ultrasound (US) attenuation imaging is an upcoming tool for noninvasive quantitative assessment of hepatic steatosis in children. A limited number of publications have focused on US attenuation imaging and the stages of hepatic steatosis in children. OBJECTIVE: To analyze the usefulness of ultrasound attenuation imaging for the diagnosis and quantification of hepatic steatosis in children. MATERIAL AND METHODS: Between July and November 2021, 174 patients were included and divided into two groups: group 1, patients with risk factors for steatosis (n = 147), and group 2, patients without risk factors for steatosis (n = 27). In all cases, age, sex, weight, body mass index (BMI), and BMI percentile were determined. B-mode US (two observers) and US attenuation imaging with attenuation coefficient acquisition (two independent sessions, two different observers) were performed in both groups. Steatosis was classified into four grades (0: absent, 1: mild, 2: moderate and 3: severe) using B-mode US. Attenuation coefficient acquisition was correlated with steatosis score according to Spearman's correlation. Attenuation coefficient acquisition measurements' interobserver agreement was assessed using intraclass correlation coefficients (ICC). RESULTS: All attenuation coefficient acquisition measurements were satisfactory without technical failures. The median values for group 1 for the first session were 0.64 (0.57-0.69) dB/cm/MHz and 0.64 (0.60-0.70) dB/cm/MHz for the second session. The median values for group 2 for the first session were 0.54 (0.51-0.56) dB/cm/MHz and 0.54 (0.51-0.56) dB/cm/MHz for the second. The average attenuation coefficient acquisition was 0.65 (0.59-0.69) dB/cm/MHz for group 1 and 0.54 (0.52-0.56) dB/cm/MHz for group 2. There was excellent interobserver agreement at 0.94 (95% CI 0.92-0.96). There was substantial agreement between both observers (κ = 0.77, with a P < 0.001). There was a positive correlation between ultrasound attenuation imaging and B-mode scores for both observers (r = 0.87, P < 0.001 for observer 1; r = 0.86, P < 0.001 for observer 2). Attenuation coefficient acquisition median values were significantly different for each steatosis grade (P < 0.001). In the assessment of steatosis by B-mode US, the agreement between the two observers was moderate (κ = 0.49 and κ = 0.55, respectively, with a P < 0.001 in both cases). CONCLUSION: US attenuation imaging is a promising tool for the diagnosis and follow-up of pediatric steatosis, which provides a more repeatable form of classification, especially at low levels of steatosis detectable in B-mode US.

Identification of Bone Mineral Density Deficit Using L1 Trabecular Attenuation by Opportunistic Multidetector CT Scan in Adult Patients.

BACKGROUND: Multidetector computer tomography (CT) has been used to diagnose pathologies such as osteoporosis via opportunistic screening, where the assessment of the bone structure and the measurement of bone mineral density (BMD) are of great relevance. PURPOSE: To construct reference BMD values based on the measurement of the attenuation of the L1 vertebral body by multidetector CT scan (in the soft tissue and bone windows) in adult patients and to establish normative ranges by sex and age of BMD values. MATERIALS AND METHODS: A retrospective cross-sectional study of 5080 patients who underwent multidetector CT scan between January and December 2021. Adult patients (≥18 years) with non-contrast multidetector CT scan of the abdomen or thorax-abdomen at a voltage 120 kV. The attenuation of the L1 vertebral body in Hounsfield units (HU) in both windows were compared using the Mann-Whitney U-test with α = 0.05. Additionally, the quartiles of the BMD were constructed (in both windows) grouped by sex and age. RESULTS: Only 454 (51.30 ± 15.89 years, 243 women) patients met the inclusion criteria. There is no difference in BMD values between windows (soft tissue: 163.90 ± 57.13, bone: 161.86 ± 55.80, p = 0.625), mean L1 attenuation decreased linearly with age at a rate of 2 HU per year, and the presence of BMD deficit among patients was high; 152 of 454 (33.48%) patients presented BMD values suggestive of osteoporosis, and of these, approximately half 70 of 454 (15.42%) corresponded to patients with BMD values suggestive of a high risk of osteoporotic fracture. CONCLUSIONS: From clinical practice, the bone mineral density (BMD) of a patient in either window below the first quartile for age- and sex-matched peers suggests a deficit in BMD that cannot be ignored and requires clinical management that enables identification of the etiology, its evolution, and the consequences of this alteration.

Peri-osteosarcoma adipose computed tomography attenuation and volume for predicting chemotherapy response in pediatric patients.

BACKGROUND: The chemosensitivity of osteosarcoma patients to MTX is closely related to prognosis. There is currently a lack of advance prediction methods for MTX sensitivity. OBJECTIVE: We proposed novel peri-osteosarcoma fat parameters based on computed tomography (CT) to evaluate the chemotherapy response preoperatively and calculate the correlation between image characteristics and methotrexate (MTX) blood concentration and systemic inflammation. MATERIALS AND METHODS: Pediatric patients with osteosarcoma (OS) who were treated with high-dose MTX were retrospectively studied and grouped according to postoperative Huvos classification. Clinical data were collected and reviewed. Image characteristics including peri-osteosarcoma fat volume and fat attenuation index were measured using the threshold method based on CT images. Statistical significance, correlation and prediction performance were performed. RESULTS: Eighteen patients (good response (GR) group/poor response (PR) group: 10/8) was enrolled. MTX peak value at 6 h differed significantly between the two groups which was significantly higher in GR group (745.1 µmol/L vs 529.0 µmol/L p = 0.001). Peri-osteosarcoma fat attenuation index was significantly lower in GR group compared with that in PR group (- 104.90 vs. - 97.19, p < 0.0001). MTX blood concentration at 6 h negatively correlated with peri-osteosarcoma fat attenuation index (R = - 0.519, p = 0.027). In addition, 6 h MTX blood concentration (OR 0.974; 95% CI 0.951-0.998, p = 0.037) and FAI (OR 2.108; 95% CI 1.047-4.243, p = 0.037) were, respectively, independently related to good response to chemotherapy. The prediction performance on chemotherapy response of peri-osteosarcoma fat attenuation index and 6 h MTX blood concentration were both good with the comparable area under the ROC curve (0.950, 95% CI 0.856-1.000 and 0.963, 95% CI 0.878-1.00). CONCLUSIONS: Peri-osteosarcoma fat parameters based on CT were associated with the chemotherapy response and the MTX blood concentration, but not with the systemic inflammation. Combined with the requirement of current clinical practice, peri-osteosarcoma fat parameters may have the potential to be valuable image characteristics for monitoring chemotherapy response in OS pediatric patients.

Potassium fertilization as salt stress attenuator in sour passion fruit / Adubação potássica como atenuante do estresse salino em maracujazeiro-azedo

Water scarcity associated with irregular rainfall in the semi-arid region of Northeastern Brazil stands out as a limiting factor for agricultural production. Thus, the use of waters with high concentration of salts is an alternative to expand irrigated agriculture in this region. In this context, this study evaluated the water status, intercellular electrolyte leakage, photosynthetic pigments, and gas exchange of 'BRS SC1' sour passion fruit as a function of irrigation with water of different levels of salinity and potassium doses. The experiment was carried out in pots adapted as drainage lysimeters under field conditions at the Experimental Farm of the Federal University of Campina Grande in São Domingos - PB, Brazil. The experimental design was randomized blocks, in a 5 × 4 factorial scheme, whose treatments were obtained by combining two factors: five levels of electrical conductivity of irrigation water - ECw (0.3, 1.1, 1.9, 2.7, and 3.5 dS m-1), associated with four potassium doses (60, 80, 100, and 120% of the recommendation), with three replicates. Water with electrical conductivity greater than 0.3 dS m-1 reduced the relative water content, chlorophyll a and chlorophyll b contents, CO2 assimilation rate, and instantaneous water use efficiency of 'BRS SC1' sour passion fruit plants. The estimated potassium dose of 85% of the recommendation (equivalent to 293 g per plant per year) mitigated the deleterious effects of salt stress on stomatal conductance, transpiration, internal CO2 concentration, and instantaneous carboxylation efficiency of passion fruit 'BRS SC1'.

Water scarcity associated with irregular rainfall in the semi-arid region of Northeastern Brazil stands out as a limiting factor for agricultural production. Thus, the use of waters with high concentration of salts is an alternative to expand irrigated agriculture in this region. In this context, this study evaluated the water status, intercellular electrolyte leakage, photosynthetic pigments, and gas exchange of 'BRS SC1' sour passion fruit as a function of irrigation with water of different levels of salinity and potassium doses. The experiment was carried out in pots adapted as drainage lysimeters under field conditions at the Experimental Farm of the Federal University of Campina Grande in São Domingos - PB, Brazil. The experimental design was randomized blocks, in a 5 × 4 factorial scheme, whose treatments were obtained by combining two factors: five levels of electrical conductivity of irrigation water - ECw (0.3, 1.1, 1.9, 2.7, and 3.5 dS m-1), associated with four potassium doses (60, 80, 100, and 120% of the recommendation), with three replicates. Water with electrical conductivity greater than 0.3 dS m-1 reduced the relative water content, chlorophyll a and chlorophyll b contents, CO2 assimilation rate, and instantaneous water use efficiency of 'BRS SC1' sour passion fruit plants. The estimated potassium dose of 85% of the recommendation (equivalent to 293 g per plant per year) mitigated the deleterious effects of salt stress on stomatal conductance, transpiration, internal CO2 concentration, and instantaneous carboxylation efficiency of passion fruit 'BRS SC1'.

Inflamação Coronária Avaliada pela Atenuação de Gordura Pericoronária na Tomografia Computadorizada e Elevação de Citocinas em Usuários Jovens de Esteroides Anabólicos Androgênicos / Coronary Inflammation by Computed Tomography Pericoronary Fat Attenuation and Increased Cytokines in Young Male Anabolic Androgenic Steroid Users

Resumo Fundamento O uso abusivo de esteroides anabólicos androgênicos (EAA) tem sido associado à doença arterial coronariana (DAC). A atenuação de gordura pericoronária (AGp) é um marcador de inflamação coronária, a qual exerce um papel chave no processo aterosclerótico. Objetivo Avaliar AGp e perfil inflamatório em usuários de EAA. Método Vinte indivíduos que realizavam treinamento de força, usuários de EAA (UEAA), 20 não usuários de EAA (NUEAA), e 10 indivíduos sedentários controle (SC) foram avaliados. Inflamação coronária foi avaliada por atenuação de gordura pericoronária média (AGPm) artéria coronária direita (ACD), artéria descendente anterior esquerda (ADA) e artéria circunflexa (ACX). Interleucina (IL)-1 (IL-1), IL-6, IL-10, e TNF-alfa foram avaliados por densidade ótica (DO) em um espectrofotômetro com um filtro de 450 nm. Um p<0,05 indicou significância estatística. Resultados Os UEAA apresentaram maior AGPm na ACD [-65,87 (70,51-60,70) vs. -78,07 (83,66-72,87) vs.-78,46 (85,41-71,99] unidades Hounsfield (HU), respectivamente, p<0,001) e AGPm na ADA [-71,47 (76,40-66,610 vs. -79,32 (84,37-74,59) vs. -82,52 (88,44-75,81) HU, respectivamente, p=0,006) em comparação aos NUEAA e CS. A AGPm na ACX não foi diferente entre os grupos UEAA, NUEAA e CS [-72,41 (77,17-70,37) vs. -80,13 (86,22-72,23) vs. -78,29 (80,63-72,29) HU, respectivamente, p=0,163). Em comparação aos NUEAA e aos CS, o grupo UEAA apresentaram maiores níveis de IL-1 [0,975 (0,847-1,250) vs. 0,437 (0,311-0,565) vs. 0,530 (0,402-0,780) DO, respectivamente, p=0,002), IL-6 [1,195 (0,947-1,405) vs. 0,427 (0,377-0,577) vs. 0,605 (0,332-0,950) DO, p=0,005) e IL-10 [1,145 (0,920-1,292) vs. 0,477 (0,382-0,591) vs. 0,340 (0,316-0,560) DO, p<0,001]. TNF-α não foi diferente entre os grupos UEAA, NUEAA e CS [0,520 (0,250-0,610) vs. 0,377 (0.261-0,548) vs. 0,350 (0,182-430)]. Conclusão Em comparação aos NUEAA e controles, os UEAA apresentam maior AGPm e maior perfil de citocinas inflamatórias sistêmicas, sugerindo que os EAA podem induzir aterosclerose por inflamação coronária e sistêmica.

Abstract Background Anabolic androgenic steroid (AAS) abuse has been associated with coronary artery disease (CAD). Pericoronary fat attenuation (pFA) is a marker of coronary inflammation, which is key in the atherosclerotic process. Objective To evaluate pFA and inflammatory profile in AAS users. Methods Twenty strength-trained AAS users (AASU), 20 AAS nonusers (AASNU), and 10 sedentary controls (SC) were evaluated. Coronary inflammation was evaluated by mean pericoronary fat attenuation (mPFA) in the right coronary artery (RCA), left anterior descending coronary artery (LAD), and left circumflex (LCx). Interleukin (IL)-1 (IL-1), IL-6, IL-10, and TNF-alpha were evaluated by optical density (OD) in a spectrophotometer with a 450 nm filter. P<0.05 indicated statistical significance. Results AASU had higher mPFA in the RCA (-65.87 [70.51-60.70] vs. -78.07 [83.66-72.87] vs.-78.46 [85.41-71.99] Hounsfield Units (HU), respectively, p<0.001) and mPFA in the LAD (-71.47 [76.40-66.61] vs. -79.32 [84.37-74.59] vs. -82.52 [88.44-75.81] HU, respectively, p=0.006) compared with AASNU and SC. mPFA in the LCx was not different between AASU, AASNU, and SC (-72.41 [77.17-70.37] vs. -80.13 [86.22-72.23] vs. -78.29 [80.63-72.29] HU, respectively, p=0.163). AASU compared with AASNU and SC, had higher IL-1, (0.975 [0.847-1.250] vs. 0.437 [0.311-0.565] vs. 0.530 [0.402-0.780] OD, respectively, p=0.002), IL-6 (1.195 [0.947-1.405] vs. 0.427 [0.377-0.577] vs. 0.605 [0.332-0.950] OD, p=0.005) and IL-10 (1.145 [0.920-1.292] vs. 0.477 [0.382-0.591] vs. 0.340 [0.316-0.560] OD, p<0.001). TNF-α was not different between the AASU, AASNU, and SC groups (0.520 [0.250-0.610] vs. 0.377 [0.261-0.548] vs. 0.350 [0.182-430]), respectively. Conclusion Compared with ASSNU and controls, AASU have higher mPFA and higher systemic inflammatory cytokines profile suggesting that AAS may induce coronary atherosclerosis through coronary and systemic inflammation.

Insights into the Effect of Aggregate Sizes on the Soil Radiation Interaction Properties Based on X-ray Fluorescence.

Soils subjected to disaggregation can break into aggregates of different sizes composed of sand, clay, and silt particles. Each aggregate contains different oxides, which can vary according to the aggregate size and influence its properties, such as the radiation interaction parameters. These parameters are relevant in the evaluation of radiation shielding and soil physical properties. Thirteen tropical/subtropical soils of contrasting textures (clayey and loamy/sandy) with two aggregate sizes (2-1 mm and <45 µm) were studied. The radiation parameters analyzed were the atomic (σA), electronic (σE), and molecular (σM) cross-sections; the effective atomic number (Zeff); and the electron density (Nel). We verified that the aggregate sizes affected the major oxides (SiO2, Al2O3, Fe2O3). In general, the attenuation coefficient and Zeff were sensitive to the clayey soils' aggregate sizes (low photon energies). However, the loamy/sandy soils did not exhibit differences among the parameters. As the photon energy increased, only Zeff presented differences for most soils. We also verified that σM, Zeff, and Nel were the most sensitive parameters to the soil composition. Although the soil chemical composition was influenced by the studied aggregate sizes, the radiation parameters exhibited differences for only some of these parameters. This means that the aggregate size is practically irrelevant when radiation parameters are determined based on X-ray fluorescence.

The effect of positional disorder and the Beer-Lambert law in organic photovoltaics : A kinetic Monte Carlo simulation analysis.

It is urgent to address climate change by radically changing our energy sources. Organic photovoltaics (OPVs) are a competitive clean energy emerging technology and will undoubtedly have a market niche in a world that needs to take advantage of every possible type of renewable energy. Recent studies have brought relevant improvements on internal efficiency, focusing on two properties at the interface: energetic disorder and bending. However, how positional disorder affects internal efficiency is still an open question. Here, we show that positional disorder is desired at the interface, but only up to a threshold value of 0.2 nm for poly p-phenylene vinylene. Using a kinetic Monte Carlo simulator, we realized that not enough excitons were reaching the interface, and introduced the Beer-Lambert law of attenuance to correct it. Furthermore, we realized that the same disorder that facilitates charge separation at the interface diminishes exciton and charge mobility in bulk, so we propose here a new morphology for the active layer of OPVs. Our suggestion implicates in better overall performance, improving not just the internal but the overall cell efficiency.

Risk factors associated with nonalcoholic fatty liver disease evaluated by elastography in patients with type 2 diabetes

ABSTRACT Objective: There is controversy about the indication for nonalcoholic fatty liver disease (NAFLD) screening in patients with type 2 diabetes mellitus (T2D). The present study aims to contribute to NAFLD surveillance in patients with T2D, assessing the association of clinical and biological variables with hepatic stiffness and steatosis. Subjects and methods: A cross-sectional design was used, with data collection from electronic medical records, including adults with T2D who underwent transient elastography (TE) between June 2018 and December 2019. Liver stiffness and steatosis were evaluated using TE and controlled attenuation parameter (CAP), respectively, with cutoff points > 8 kpa for increased stiffness and > 275 dBm for steatosis. The relationship between clinical variables and elastography results were evaluated by bivariate correlation and multivariate analysis, using SPSS 27. Seventy-nine patients (n = 79) met the inclusion and exclusion criteria. Results: Advanced fibrosis and hepatic steatosis were detected in 17,7% and in 21,5% of the patients, respectively. There was a direct and significant correlation between CAP and BMI, waist circumference, HbA1c, triglycerides levels, and insulin doses and an inverse correlation with HDL. The waist circumference, low levels of HDL cholesterol and the insulin dose maintained a significant association with CAP values in multivariate analysis. Elastography values showed an inverse correlation with HDL and a direct correlation with BMI and insulin dose. The association was only maintained for the insulin dose in multivariate analysis. Conclusion: Our results suggest that clinical factors such as insulin dose, waist circumference, and HDL cholesterol levels could identify T2D patients more likely to present NAFLD.

Modeling Radio Wave Propagation for Wireless Sensor Networks in Vegetated Environments: A Systematic Literature Review.

The use of wireless sensor networks (WSN) for monitoring variables in agricultural environments and natural forests has been increasing in recent years. However, the sizing of these systems is affected by the inaccuracy of the radio wave propagation models used, leading to possible increased costs and measurement errors. This systematic literature review (SLR) aims to identify propagation models widely used in WSN deployments in agricultural or naturally vegetated environments and their effectiveness in estimating signal losses. We also identified today's wireless technologies most used in precision agriculture (PA) system implementations. In addition, the results of studies focused on the development of new propagation models for different environments are evaluated. Scientific and technical analysis is presented based on articles consulted in different specialized databases, which were selected according to different combinations of criteria. The results show that, in most of the application cases, vegetative models present high error values when estimating attenuation.

Risk factors associated with nonalcoholic fatty liver disease evaluated by elastography in patients with type 2 diabetes.

Objective: There is controversy about the indication for nonalcoholic fatty liver disease (NAFLD) screening in patients with type 2 diabetes mellitus (T2D). The present study aims to contribute to NAFLD surveillance in patients with T2D, assessing the association of clinical and biological variables with hepatic stiffness and steatosis. Subjects and methods: A cross-sectional design was used, with data collection from electronic medical records, including adults with T2D who underwent transient elastography (TE) between June 2018 and December 2019. Liver stiffness and steatosis were evaluated using TE and controlled attenuation parameter (CAP), respectively, with cutoff points > 8 kpa for increased stiffness and > 275 dBm for steatosis. The relationship between clinical variables and elastography results were evaluated by bivariate correlation and multivariate analysis, using SPSS 27. Seventy-nine patients (n = 79) met the inclusion and exclusion criteria. Results: Advanced fibrosis and hepatic steatosis were detected in 17,7% and in 21,5% of the patients, respectively. There was a direct and significant correlation between CAP and BMI, waist circumference, HbA1c, triglycerides levels, and insulin doses and an inverse correlation with HDL. The waist circumference, low levels of HDL cholesterol and the insulin dose maintained a significant association with CAP values in multivariate analysis. Elastography values showed an inverse correlation with HDL and a direct correlation with BMI and insulin dose. The association was only maintained for the insulin dose in multivariate analysis. Conclusion: Our results suggest that clinical factors such as insulin dose, waist circumference, and HDL cholesterol levels could identify T2D patients more likely to present NAFLD.

Comparative assessment of abdominal and thigh muscle characteristics using CT-derived images.

OBJECTIVES: The aim of this study was to compare the assessment of skeletal muscle area (SMA in cm²), skeletal muscle index (SMI in cm²/m²), and skeletal muscle density (SMD in HU) between third lumbar vertebra (L3) and thigh landmarks, and the agreement in diagnosing low muscle mass and low SMD (L3 as the reference method). METHODS: This was a multicenter, cross-sectional study including healthy individuals (≥18 y of age) of both sexes, who had an elective computed tomography exam including abdominal and pelvic regions. Computed tomography images were analyzed to evaluate SMA, SMI, and SMD. Muscle abnormalities (low SMA, SMI, and SMD) were defined as values below the fifth percentile from a subsample of healthy young individuals (n = 111; 18-39 y of age; 55.9% women). Correlation coefficients, Bland-Altman graphs, and receiver operating characteristic (ROC) curves were calculated for the total sample and stratified by sex and age. RESULTS: In all, 268 individuals (44.3 ± 15.2 y of age) were evaluated (53% women). Significant (P < 0.001 for all analysis) and strong correlations between SMA (r = 0.896), SMI (r= 0.853), and SMD (r= 0.864) compared with L3 and thigh landmarks were observed. For the ROC curves, similar areas under the curve values were obtained for men (0.981), women (0.895), younger (0.902), and older adults (0.894). CONCLUSIONS: Muscle characteristics between L3and thigh landmarks have a strong correlation. This suggests that images of the thigh can be used to characterize muscle characteristics. Image acquisition and analysis of thigh region is simpler, with less radiation exposure, and consequently more appropriate for longitudinal analysis.

Integron Functionality and Genome Innovation: An Update on the Subtle and Smart Strategy of Integrase and Gene Cassette Expression Regulation.

Integrons are considered hot spots for bacterial evolution, since these platforms allow one-step genomic innovation by capturing and expressing genes that provide advantageous novelties, such as antibiotic resistance. The acquisition and shuffling of gene cassettes featured by integrons enable the population to rapidly respond to changing selective pressures. However, in order to avoid deleterious effects and fitness burden, the integron activity must be tightly controlled, which happens in an elegant and elaborate fashion, as discussed in detail in the present review. Here, we aimed to provide an up-to-date overview of the complex regulatory networks that permeate the expression and functionality of integrons at both transcriptional and translational levels. It was possible to compile strong shreds of evidence clearly proving that these versatile platforms include functions other than acquiring and expressing gene cassettes. The well-balanced mechanism of integron expression is intricately related with environmental signals, host cell physiology, fitness, and survival, ultimately leading to adaptation on the demand.