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1.
J Thorac Imaging ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39257277

RESUMO

PURPOSE: To compare texture-based analysis using convolutional neural networks (CNNs) against lung densitometry in detecting chest computed tomography (CT) image abnormalities. MATERIAL AND METHODS: A U-NET was used for lung segmentation, and an ensemble of 7 CNN architectures was trained for the classification of low-attenuation areas (LAAs; emphysema, cysts), normal-attenuation areas (NAAs; normal parenchyma), and high-attenuation areas (HAAs; ground-glass opacities, crazy paving/linear opacity, consolidation). Lung densitometry also computes (LAAs, ≤-950 HU), NAAs (-949 to -700 HU), and HAAs (-699 to -250 HU). CNN-based and densitometry-based severity indices (CNN and Dens, respectively) were calculated as (LAA+HAA)/(LAA+NAA+HAA) in 812 CT scans from 176 normal subjects, 343 patients with emphysema, and 293 patients with interstitial lung disease (ILD). The correlation between CNN-derived and densitometry-derived indices was analyzed, alongside a comparison of severity indices among patient subgroups with emphysema and ILD, using the Spearman correlation and ANOVA with Bonferroni correction. RESULTS: CNN-derived and densitometry-derived severity indices (SIs) showed a strong correlation (ρ=0.90) and increased with disease severity. CNN-SIs differed from densitometry SIs, being lower for emphysema and higher for moderate to severe ILD cases. CNN estimations for normal attenuation areas were higher than those from densitometry across all groups, indicating a potential for more accurate characterization of lung abnormalities. CONCLUSIONS: CNN outputs align closely with densitometry in assessing lung abnormalities on CT scans, offering improved estimates of normal areas and better distinguishing similar abnormalities. However, this requires higher computing power.

2.
Chem Biodivers ; 17(5): e2000107, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32222029

RESUMO

Extracts and compounds obtained from several species of Celastraceae family are reported as potential sources of drugs due to their diverse pharmacological properties. Nevertheless, essential oil composition from these species is still little known. This work aimed at the analysis of essential oils obtained from different Brazilian Celastraceae species. A total of seventeen oils were obtained using hydrodistillation process and analyzed by gas chromatography/mass spectrometry (GC/MS). Principal component analysis (PCA) allowed the identification of a chemical composition pattern among the analyzed essential oils. Some compounds were more frequent among Celastraceae species, such as cis- and trans-linalool oxide (14/17 oil samples), nerylacetone (13/17), linalool (11/17), ß-ionone (10/17), α-ionone (9/17), nerolidol (10/17), decanal (10/17), and dodecanoic acid (10/17). These results contribute to the chemophenetics of Celastraceae species.


Assuntos
Celastraceae/química , Óleos Voláteis/análise , Brasil , Cromatografia Gasosa-Espectrometria de Massas , Análise de Componente Principal , Especificidade da Espécie
3.
Curr Pharm Des ; 26(33): 4056-4091, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32209036

RESUMO

Species from the Annona (Anonaceae) genus are used in traditional medicine for the treatment of various diseases. Ethnobotanical studies provide information regarding the plant part and the preparation method being used, while scientific studies such as in vitro, in vivo, and clinical tests can provide evidence supporting ethnopharmacological reports, directing studies towards the isolation of compounds which may be active for specific pathologies. Annona muricata and Annona squamosa were the most commonly reported species from those studied, with Annona cherimola and Annona classiflora also standing out. Acetogenins were the most commonly isolated metabolite class due to their cytotoxic properties, with flavonoids, alkaloids, steroids, and peptides also being reported. Many species from the Annona genus have proven biological activities, such as antitumor, antioxidant, antimicrobial and antifungal. The present review had as its objective to facilitate access to ethnobotanical, chemical and biological information in order to direct future researches.


Assuntos
Annona , Etnobotânica , Etnofarmacologia , Humanos , Medicina Tradicional , Fitoterapia , Extratos Vegetais/farmacologia
5.
J Nutr ; 144(10): 1571-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25122644

RESUMO

Many studies have shown that risk factors that are independent of blood pressure (BP) can contribute to the development of cardiac hypertrophy (CH). Among these factors, high-salt (HS) intake was prominent. Although some studies have attempted to elucidate the role of salt in the development of this disease, the mechanisms by which salt acts are not yet fully understood. Thus, the aim of this study was to better understand the mechanisms of CH and interstitial fibrosis (IF) caused by HS intake. Male Wistar rats were divided into 5 groups according to diet [normal salt (NS; 1.27% NaCl) or HS (8% NaCl)] and treatment [losartan (LOS) (HS+LOS group), hydralazine (HZ) (HS+HZ group), or N-acetylcysteine (NAC) (HS+NAC group)], which was given in the drinking water. Tail-cuff BP, transverse diameter of the cardiomyocyte, IF, angiotensin II type 1 receptor (AT1) gene and protein expression, serum aldosterone, cardiac angiotensin II, cardiac thiobarbituric acid-reactive substances, and binding of conformation-specific anti-AT1 and anti-angiotensin II type 2 receptor (AT2) antibodies in the 2 ventricles were measured. Based on the left ventricle transverse diameter data, the primary finding was the occurrence of significant BP-independent CH in the HS+HZ group (96% of the HS group) and a partial or total prevention of such hypertrophy via treatment with NAC or LOS (81% and 67% of the HS group, respectively). The significant total or partial prevention of IF using all 3 treatments (HS+HZ, 27%; HS+LOS, 27%; and HS+NAC, 58% of the HS group, respectively), and an increase in the AT1 gene and protein expression and activity in groups that developed CH, confirmed that CH occurred via the AT1 in this experimental model. Thus, this study unveiled some relevant previously unknown mechanisms of CH induced by chronic HS intake in Wistar rats. The link of oxidative stress with CH in our experimental model is very interesting and stimulates further evaluation for its full comprehension.


Assuntos
Cardiomegalia/patologia , Miócitos Cardíacos/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina/metabolismo , Cloreto de Sódio na Dieta/efeitos adversos , Acetilcisteína/farmacologia , Aldosterona/sangue , Angiotensina II/metabolismo , Animais , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal , Cardiomegalia/induzido quimicamente , Cardiomegalia/genética , Frequência Cardíaca , Hematócrito , Hidralazina/farmacologia , Losartan/farmacologia , Masculino , Miócitos Cardíacos/metabolismo , Potássio/sangue , Potássio/urina , Ratos , Ratos Wistar , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 2 de Angiotensina/genética , Receptor Tipo 2 de Angiotensina/metabolismo , Sistema Renina-Angiotensina/efeitos dos fármacos , Sódio/sangue , Sódio/urina , Cloreto de Sódio na Dieta/administração & dosagem , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
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