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1.
Med Biol Eng Comput ; 61(6): 1409-1425, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36719564

ABSTRACT

Cardiovascular diseases are among the leading causes of mortality worldwide, with more than 23 million related deaths per year by 2030, according to the World Heart Federation. Although most of these diseases may be prevented, population awareness strategies are still ineffective. In this context, we propose the CML-Cardio tool, a machine learning application to automate the risk classification process of developing CVDs. For this, researchers in our group collected data on diabetes, blood pressure, and other risk factors in a private company. Our final model consists of a cascade system to handle highly imbalanced data. In the first stage, a binary model is responsible for predicting whether a patient has a low risk of developing CVDs or if has a risk that needs attention. In this step, we use six algorithms: logistic regression, SVM, random forest, XGBoost, CatBoost, and multilayer perceptron. The better results presented an average accuracy of 0.86 ± 0.03 and f-score of 0.85 ± 0.04. We interpret each feature's impact on the models' output and validate the subsystem for the next step. In the second stage, we use an anomaly detection model to learn the intermediate risk patterns present in the instances that need attention. The cascade model presented an average accuracy of 0.80 ± 0.07 and f-score of 0.70 ± 0.07. Finally, we develop the CML-Cardio prototype of an actual application as a primary prevention strategy. Graphical abstract In this work, we propose the CML-Cardio tool, a cascade machine learning method to classify cardiovascular disease risk.


Subject(s)
Cardiovascular Diseases , Humans , Cardiovascular Diseases/prevention & control , Algorithms , Blood Pressure , Machine Learning , Primary Prevention
2.
Comput Biol Med ; 132: 104335, 2021 05.
Article in English | MEDLINE | ID: mdl-33812263

ABSTRACT

The sudden outbreak of coronavirus disease 2019 (COVID-19) revealed the need for fast and reliable automatic tools to help health teams. This paper aims to present understandable solutions based on Machine Learning (ML) techniques to deal with COVID-19 screening in routine blood tests. We tested different ML classifiers in a public dataset from the Hospital Albert Einstein, São Paulo, Brazil. After cleaning and pre-processing the data has 608 patients, of which 84 are positive for COVID-19 confirmed by RT-PCR. To understand the model decisions, we introduce (i) a local Decision Tree Explainer (DTX) for local explanation and (ii) a Criteria Graph to aggregate these explanations and portrait a global picture of the results. Random Forest (RF) classifier achieved the best results (accuracy 0.88, F1-score 0.76, sensitivity 0.66, specificity 0.91, and AUROC 0.86). By using DTX and Criteria Graph for cases confirmed by the RF, it was possible to find some patterns among the individuals able to aid the clinicians to understand the interconnection among the blood parameters either globally or on a case-by-case basis. The results are in accordance with the literature and the proposed methodology may be embedded in an electronic health record system.


Subject(s)
COVID-19 , Brazil , Decision Trees , Hematologic Tests , Humans , Machine Learning , SARS-CoV-2
3.
Appl Sci (Basel) ; 11(2)2021 Jan 02.
Article in English | MEDLINE | ID: mdl-33680505

ABSTRACT

Magnetic Resonance Imaging-based prostate segmentation is an essential task for adaptive radiotherapy and for radiomics studies whose purpose is to identify associations between imaging features and patient outcomes. Because manual delineation is a time-consuming task, we present three deep-learning (DL) approaches, namely UNet, efficient neural network (ENet), and efficient residual factorized convNet (ERFNet), whose aim is to tackle the fully-automated, real-time, and 3D delineation process of the prostate gland on T2-weighted MRI. While UNet is used in many biomedical image delineation applications, ENet and ERFNet are mainly applied in self-driving cars to compensate for limited hardware availability while still achieving accurate segmentation. We apply these models to a limited set of 85 manual prostate segmentations using the k-fold validation strategy and the Tversky loss function and we compare their results. We find that ENet and UNet are more accurate than ERFNet, with ENet much faster than UNet. Specifically, ENet obtains a dice similarity coefficient of 90.89% and a segmentation time of about 6 s using central processing unit (CPU) hardware to simulate real clinical conditions where graphics processing unit (GPU) is not always available. In conclusion, ENet could be efficiently applied for prostate delineation even in small image training datasets with potential benefit for patient management personalization.

4.
Cancers (Basel) ; 12(6)2020 Jun 08.
Article in English | MEDLINE | ID: mdl-32521645

ABSTRACT

To date, diffusion weighted imaging (DWI) is included in routine magnetic resonance imaging (MRI) protocols for several cancers. The real additive role of DWI lies in the "functional" information obtained by probing the free diffusivity of water molecules into intra and inter-cellular spaces that in tumors mainly depend on cellularity. Although DWI has not gained much space in some oncologic scenarios, this non-invasive tool is routinely used in clinical practice and still remains a hot research topic: it has been tested in almost all cancers to differentiate malignant from benign lesions, to distinguish different malignant histotypes or tumor grades, to predict and/or assess treatment responses, and to identify residual or recurrent tumors in follow-up examinations. In this review, we provide an up-to-date overview on the application of DWI in oncology.

5.
Hematol Oncol ; 38(1): 12-21, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31486520

ABSTRACT

The improvements in magnetic resonance imaging (MRI) technology and the concern related to the increased cancer risk in patients with lymphoma, also due to radiation exposure associated with imaging examinations, have led to the introduction of whole-body MRI (WB-MRI) as a radiation-free alternative to standard imaging procedures. WB-MRI seems a less histology-dependent functional imaging test than 18 F-fluorodeoxyglucose-positron emission tomography/CT (18 F-FDG-PET/CT). In patients with FDG-avid lymphomas, such as diffuse large B-cell lymphoma (DLBCL) and Hodgkin lymphoma (HL), 18 F-FDG-PET/CT remains the imaging reference standard for staging, with WB-MRI potentially being a complementary modality that could replace CT, especially in young patients. On the other hand, WB-MRI is a valuable imaging procedure for lymphoma surveillance and in lymphomas with variable/low FDG avidity and nonfollicular indolent lymphomas. The aim of this paper is to discuss the current state of the art of WB-MRI in lymphoma by evaluating its diagnostic performance in different lymphoma subtypes: Hodgkin, aggressive, and indolent lymphomas.


Subject(s)
Lymphoma/diagnosis , Magnetic Resonance Imaging/methods , Whole Body Imaging/methods , Animals , Humans , Neoplasm Staging
6.
Curr Probl Diagn Radiol ; 49(6): 398-403, 2020.
Article in English | MEDLINE | ID: mdl-31253462

ABSTRACT

PURPOSE: To compare magnetic resonance imaging (MRI) findings with gadoxetic acid and gadobenate dimeglumine for the diagnosis of hepatic hemangiomas. MATERIALS AND METHODS: In this retrospective study, we included 26 hemangiomas (mean size was 14 mm ± 10 mm) in 19 patients (mean age 60 ± 14 years) scanned with both gadobenate dimeglumine MRI and gadoxetic acid MRI. For each patient, we collected multiple lesion variables including location, number, size and enhancement pattern on arterial, portal venous, 3-minute and hepatobiliary phases with both gadoxetic acid and gadobenate dimeglumine. The enhancement pattern with the two contrast agents was then compared. RESULTS: The typical enhancement pattern of hepatic hemangiomas was more common-though not statistically significant-with gadobenate dimeglumine compared to gadoxetic acid (57% [15 of 26] vs 42% [11 of 26], respectively; P = 0.4057 for both peripheral globular discontinuous enhancement in the arterial phase and centripetal fill-in in the portal venous phase). A significantly higher number of hemangiomas showed centripetal fill-in or hyperintensity in the 3-minute phase with gadobenate dimeglumine compared to gadoxetic acid (88% [23 of 26) vs 58% [15 of 26]; P = 0.0266). A pseudo washout sign in the 3-minute phase was detected in one of the 5 flash-filling hemangiomas with gadoxetic acid, but not gadobenate dimeglumine. All hemangiomas were hypointense in the hepatobiliary phase with both gadobenate dimeglumine and gadoxetic acid. CONCLUSIONS: The enhancement pattern of hepatic hemangiomas may vary depending on the hepatobiliary agent, with more frequent lack of the typical pattern with gadoxetic acid compared to gadobenate dimeglumine.


Subject(s)
Gadolinium DTPA/administration & dosage , Hemangioma/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Magnetic Resonance Imaging/methods , Meglumine/analogs & derivatives , Organometallic Compounds/administration & dosage , Contrast Media , Female , Humans , Image Enhancement , Image Interpretation, Computer-Assisted , Male , Meglumine/administration & dosage , Middle Aged , Retrospective Studies
7.
Radiol Med ; 125(2): 204-213, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31784928

ABSTRACT

PURPOSE: To assess the prevalence and clinical significance of incidental findings (IFs) detected at multiparametric prostate MRI examination. MATERIALS AND METHODS: Multiparametric prostate MRIs of 647 consecutive patients (mean age 67.1 ± 8.0 years) were retrospectively evaluated by two radiologists recording the presence of all extra-prostatic IFs. Findings were classified as related to or not related to genitourinary system and divided into three classes, according to their clinical significance, as follows: group 1, not significant or scarcely significant; group 2, moderately or potentially significant; and group 3, significant. Differences in distribution of IFs between patients ≤ 65 years old and patients > 65 years old were assessed using Pearson's χ2 or Fisher's exact test. Statistical significance level was set at p < 0.05. RESULTS: Incidental findings (n = 461) were present in 341 (52.7%) patients, while 306 (47.3%) patients did not have any extra-prostatic IF. Overall, IFs were significantly more common in patients > 65 years old (n = 225, 57.0%) compared to patients ≤ 65 years old (n = 116, 46.0%, p = 0.007). There were 139 (30.2%) IFs related to genitourinary system and 322 (69.8%) IFs not related to genitourinary system. Group 3 IFs were almost exclusively present in patients > 65 years old (2.8%, p = 0.034) and included 7 (1.1%) bladder carcinomas, 3 (0.5%) testicle tumors, 2 (0.3%) rectal cancers. Twenty-seven (4.2%) of the 647 patients underwent surgical treatment for IFs not directly related to prostate cancer. CONCLUSION: IFs not related to prostate cancer may be frequently encountered on multiparametric prostate MRI, and they are significantly more common in patients > 65 years old.


Subject(s)
Incidental Findings , Magnetic Resonance Imaging/methods , Prostatic Neoplasms/diagnostic imaging , Adult , Aged , Aged, 80 and over , Humans , Male , Middle Aged , Prevalence , Retrospective Studies
8.
Insights Imaging ; 10(1): 1, 2019 Jan 25.
Article in English | MEDLINE | ID: mdl-30684056

ABSTRACT

The widespread use of imaging examinations has increased the detection of incidental adrenal lesions, which are mostly benign and non-functioning adenomas. The differentiation of a benign from a malignant adrenal mass can be crucial especially in oncology patients since it would greatly affect treatment and prognosis. In this setting, imaging plays a key role in the detection and characterization of adrenal lesions, with several imaging tools which can be employed by radiologists. A thorough knowledge of the imaging features of adrenal masses is essential to better characterize these lesions, avoiding a misinterpretation of imaging findings, which frequently overlap between benign and malignant conditions, thus helping clinicians and surgeons in the management of patients. The purpose of this paper is to provide an overview of the main imaging features of adrenal masses and tumor-like conditions recalling the strengths and weaknesses of imaging modalities commonly used in adrenal imaging.

11.
Minerva Urol Nefrol ; 71(2): 154-160, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30421590

ABSTRACT

BACKGROUND: To evaluate if normal and pathological prostate tissue can be distinguished by using apparent diffusion coefficient (ADC) values on magnetic resonance imaging (MRI) and to understand if it is possible to differentiate among pathological prostate tissues using ADC values. METHODS: Our population consisted in 81 patients (mean age 65.4 years) in which 84 suspicious areas were identified. Regions of interest were placed over suspicious areas, detected on MRI, and over areas with normal appearance, and ADC values were recorded. Statistical differences between ADC values of suspicious and normal areas were evaluated. Histopathological diagnosis, obtained from targeted biopsy using MRI-US fusion biopsies in 39 patients and from prostatectomy in 42 patients, were correlated to ADC values. RESULTS: Histopathological diagnosis revealed 58 cases of prostate cancer (PCa), 19 patients with indolent PCa (Gleason Score ≤6) and 39 patients with clinically significant PCa (Gleason Score ≥7), 16 of high-grade prostatic intraepithelial neoplasia (HG-PIN) and 10 of atypical small acinar proliferation (ASAP). Significant statistical differences between mean ADC values of normal prostate tissue versus PCa (P<0.00001), HG-PIN (P<0.00001) and ASAP (P<0.00001) were found. Significant differences were observed between mean ADC values of PCa versus HG-PIN (P<0.00001) and ASAP (P<0.00001) with many overlapping values. Differences between mean ADC values of HG-PIN versus ASAP (P=0.015) were not significant. Significant differences of ADC values were also observed between patients with indolent and clinically significant PCa (P<0.00001). CONCLUSIONS: ADC values allow differentiation between normal and pathological prostate tissue and between indolent and clinically significant PCa but do not allow a definite differentiation between PCa, HG-PIN, and ASAP.


Subject(s)
Diffusion Magnetic Resonance Imaging/methods , Prostatic Diseases/diagnostic imaging , Aged , Aged, 80 and over , Algorithms , Diffusion , Humans , Image Processing, Computer-Assisted , Image-Guided Biopsy , Male , Middle Aged , Neoplasm Grading , Prostate/pathology , Prostatic Neoplasms/surgery , Retrospective Studies
13.
Br J Radiol ; 90(1077): 20170077, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28590813

ABSTRACT

The widespread use of abdominal imaging techniques has increased the detection of solid renal masses over the past years. Imaging plays a crucial role in the management and surveillance and in determining which lesions need treatment. The "classical angiomyolipoma" is the only benign solid renal mass that can be characterized with confidence by imaging through the detection of a fat-containing lesion without calcifications. There is a large overlap of imaging features between benign and malignant renal masses that often makes difficult a correct characterization of these lesions. In this review, we discuss the imaging features of the main solid renal masses that may suggest a likely benign diagnosis.


Subject(s)
Diagnostic Imaging/methods , Kidney Neoplasms/diagnostic imaging , Humans , Kidney/diagnostic imaging
14.
J Biomed Opt ; 22(3): 38001, 2017 03 01.
Article in English | MEDLINE | ID: mdl-28265648

ABSTRACT

Diabetic foot ulcer (DFU) is a diabetic complication due to peripheral vasculopathy and neuropathy. A promising technology for wound healing in DFU is low-level light therapy (LLLT). Despite several studies showing positive effects of LLLT on DFU, LLLT's physiological effects have not yet been studied. The objective of this study was to investigate vascular and nervous systems modification in DFU after LLLT. Two samples of 45 DFU patients and 11 healthy controls (HCs) were recruited. The total hemoglobin (totHb) concentration change was monitored before and after LLLT by near-infrared spectroscopy and analyzed in time and frequency domains. The spectral power of the totHb changes in the very-low frequency (VLF, 20 to 60 mHz) and low frequency (LF, 60 to 140 mHz) bandwidths was calculated. Data analysis revealed a mean increase of totHb concentration after LLLT in DFU patients, but not in HC. VLF/LF ratio decreased significantly after the LLLT period in DFU patients (indicating an increased activity of the autonomic nervous system), but not in HC. Eventually, different treatment intensities in LLLT therapy showed a different response in DFU. Overall, our results demonstrate that LLLT improves blood flow and autonomic nervous system regulation in DFU and the importance of light intensity in therapeutic protocols.


Subject(s)
Diabetic Foot/therapy , Low-Level Light Therapy , Spectroscopy, Near-Infrared , Wound Healing/radiation effects , Humans , Treatment Outcome
15.
Rev. colomb. biotecnol ; 18(2): 140-146, jul.-dic. 2016. ilus, tab
Article in Spanish | LILACS | ID: biblio-959850

ABSTRACT

El objetivo del trabajo fue evaluar los efectos del carbón activado y las condiciones de oscuridad inicial sobre la propagación in vitro de banana (Musa spp.) variedad Nanicão. Fueron empleados 64 ápices provenientes de hijuelos de 20 - 30 cm. Los tratamientos consistieron en la combinación de dos concentraciones de carbón activado (2 y 3 g/l) y dos condiciones de oscuridad inicial (15 y 30 días). El diseño experimental utilizado fue completamente al azar con arreglo factorial 2 x 2 y cuatro repeticiones. Cada unidad experimental estuvo constituida por cuatro ápices. Las variables evaluadas fueron la tasa media de multiplicación, el porcentaje de supervivencia, oxidación, contaminación y aclimatización de plántulas. El análisis estadístico consistió en el ANAVA con un nivel de significancia del 5 %. Las medias fueron comparadas a través del test de Tukey al 5 % de probabilidad. Los resultados mostraron que la combinación de 2 g/l de carbón activado y 15 días de oscuridad inicial promovió el mayor porcentaje de supervivencia del primer subcultivo que alcanzo 57,30 %. En la fase de establecimiento el porcentaje de contaminación de los ápices de 39,06 % mientras que en el primer subcultivo de 22,39 %. La oxidación en la fase de establecimiento fue de 9,37 % y en el primer subcultivo fue de 8,85 %. Se concluye que la combinación entre la concentración de 2 g/l de carbón activado y 15 días de período de incubación inicial resulta efectiva en el aumento de la supervivencia de los ápices.


The objective of this work was to evaluate the effects of activated charcoal and the initial darkness conditions in the propagation in vitro of banana (Musa spp.) variety Nanicão. Were employed 64 apexes coming from shoots of approximately 20 to 30 cm. The treatments consisted in the combination of two concentrations of activated charcoal (2 and 3 g/l) and two initial dark conditions (15 and 30 days). The experimental design went completely randomized with 2 x 2 factorial arrangement and four replications. Each experimental unit consisted of four apexes. Statistical analysis consisted ANOVA with significance level of 5 %. The variables were the average rate of multiplication, survival percentage, oxidation, contamination and acclimatization of plantlets. Means were compared by Tukey test at 5 % of probability. The results showed significant difference in the interaction between the concentration of 2 g/l of activated charcoal and 15 days of initial darkness at the survival percentage from the first subculture which reached 57.30 %. In the establishment phase the percentage of contamination of the apexes was 39.06 % while that in the first subculture was 22.39 %. The oxidation in the establishment phase was 9.37 % and in the first subculture was 8.85 %. It is concluded the interaction between the concentration of 2 g/l of activated charcoal and 15 days of initial incubation period is effective in increasing survival.

17.
Clin Respir J ; 7(3): 276-80, 2013 Jul.
Article in English | MEDLINE | ID: mdl-22974193

ABSTRACT

BACKGROUND: Even if hyperglycaemia is often identified as an independent risk factor for developing respiratory tract infection, only few studies have investigated this relationship. The aim of this study is to investigate if plasma glucose on admission is related with in-hospital mortality among patients with pneumonia and to identify the glycaemic range with significant reductions of mortality risks in non-intensive care patients. METHODS: Data come from administrative records of 1018 non-intensive care patients hospitalised with diagnosis of pneumonia. For every patient, administrative records were linked with the plasma glucose. A multivariate logistic regression model was performed in order to evaluate the associations between in-hospital mortality and a set of demographic and clinical variables. Plasma glucose was added to the model as restricted cubic spline; risk estimates for hypoglycaemic and hyperglycaemic patients have been derived on the basis of this nonlinear model and presented with two values of odds ratio (OR). RESULTS: The minimal risk of in-hospital mortality was found at plasma glucose levels of mean 86 mg/dL [95% confidence interval (CI) 61-102]. The adjusted OR of deaths for plasma glucose on admission for hypoglycaemic patients (below 86 mg/dL) is 0.78 (95% CI 0.62-0.98) for each 10 mg/dL of decrease, whereas for hyperglycaemic patients (above 86 mg/dL), the OR is 1.33 (95% CI 1.07-1.66) for each 10 mg/dL of increase in plasma glucose. CONCLUSIONS: Our observations suggest that in non-intensive care patients, hypoglycaemia, as hyperglycaemia, is associated with in-hospital mortality.


Subject(s)
Blood Glucose/metabolism , Hyperglycemia/mortality , Hypoglycemia/mortality , Pneumonia/metabolism , Pneumonia/mortality , Acute Disease , Aged , Aged, 80 and over , Biomarkers/blood , Diagnostic Tests, Routine , Female , Hospital Mortality , Hospitalization , Humans , Hyperglycemia/metabolism , Hypoglycemia/metabolism , Male , Middle Aged , Predictive Value of Tests , Prognosis , Retrospective Studies , Risk Factors
18.
Acta Diabetol ; 48(4): 337-343, 2011 12.
Article in English | MEDLINE | ID: mdl-21574001

ABSTRACT

Viral infections and the metabolic syndrome may coexist in several individuals, due to the large prevalence of obesity and type 2 diabetes mellitus (T2DM). Antiviral therapy has changed the natural history of chronic viral hepatitis, but viral infection may remain undiagnosed in the absence of systematic screening. We determined the prevalence of HBV and/or HCV infection in an Italian cohort with T2DM (859 consecutive patients, 413 females) in three Italian centers: Turin, Bologna, and Naples. Screening for viral disease was coupled with the determination of parameters of metabolic syndrome. Fourteen patients were HBsAg-positive, 51 anti-HCV with a prevalence of genotype-1 infection in 58% of cases. Thirty cases had newly diagnosed viral markers, only one-third had already-diagnosed liver disease, 16 were being followed-up by a Liver Unit, and 9 cases had received antiviral treatment. Patients with viral markers had higher liver enzyme levels in comparison with virus-negative patients (P < 0.0001), whereas the prevalence of the metabolic syndrome was similar in the 2 groups. A positive correlation between BMI and alanine aminostransferase levels was only present in virus-negative cases, where the probability of enzyme levels above the upper limit of normal increased by 5% for unit of increase in BMI (OR: 1.05; 95% CI: 1.003-1.100, P = 0.037). In conclusion, the prevalence of HBV and HCV is non-negligible in patients with T2DM, but these cases may long remain undiagnosed. Elevated liver enzymes might be frequently disregarded in diabetes Units and ascribed to metabolic syndrome, thus excluding T2DM patients from specific disease-modifying antiviral treatment for hepatitis.


Subject(s)
Diabetes Mellitus, Type 2/complications , Hepatitis B/epidemiology , Hepatitis C/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Cohort Studies , Female , Hepacivirus/genetics , Hepacivirus/isolation & purification , Hepacivirus/physiology , Hepatitis B/complications , Hepatitis B/diagnosis , Hepatitis B/virology , Hepatitis B virus/genetics , Hepatitis B virus/isolation & purification , Hepatitis B virus/physiology , Hepatitis C/complications , Hepatitis C/diagnosis , Hepatitis C/virology , Humans , Italy/epidemiology , Male , Middle Aged , Young Adult
19.
Rev. bras. anal. clin ; 43(3): 213-216, 2011. ilus, tab
Article in Portuguese | LILACS | ID: lil-651506

ABSTRACT

Inúmeras evidências sustentam a hipótese de que a modificação oxidativa da LDL contribui para o desenvolvimento e progressão da aterosclerose em uma variedade de modelos animais e que as células espumosas constituem um evento crucial no desenvolvimento da lesão aterosclerótica. A LDL oxidada tem uma ação quimioatraente sobre os monócitos, induzindo a transformaçãode macrófagos em células espumosas. Neste trabalho, foi desenvolvido um protocolo simples e reproduzível de cultura de células mononucleares humanas, o qual foi utilizado para avaliação da capacidade aterogênica da LDL oxidada comparada à LDL nativa naformação de células espumosas com ativação espontânea dos macrófagos. A partir do sangue de 10 indivíduos normolipidêmicos, obteve-se a LDL por processo de ultracentrifugação sendo a mesma oxidada in vitro na presença de íons cobre. Monócitos diferenciaram-se em macrófagos e foram incubados com LDL nativa e oxidada em diferentes concentrações. Houve formação decélulas espumosas apenas em macrófagos estimulados com LDL oxidada, variando quantitativamente de acordo com a sua concentração.Concluiu-se que este protocolo de estudo, além de possibilitar a utilização de macrófagos humanos, permitiu a redução do tempo de incubação da cultura. Paralelamente, demonstrou-se que a formação de células espumosas é dependente da extensão do grau deoxidação da LDL


Much evidence sustains the hypothesis that oxidative modification of low-density lipoprotein (LDL) contributes to the development and progression of atherosclerosis and that foam cells constitute a crucial event in the development of the atheroscleroticlesion. Oxidized LDL (oxLDL) presents a chemotatic action on monocytes, inducing the transformation of macrophages into foam cells. In this work, a simple reproducible protocol for culturing human mononuclear cells was developed to evaluate the atherogeniccapacity of oxLDL compared to native LDL in the formation of foam cells. Monocytes differentiate into macrophages when stimulatedwith native and oxidized LDL at different concentrations. Foam cell formation only occurred in macrophages stimulated by oxLDL, which varied quantitatively according to its concentration. This study protocol, besides making the use of human macrophages possible, permitted a reduction in culture incubation time. Moreover, the study demonstrated that foam cell formation is dependent on the degree of LDL oxidation


Subject(s)
Young Adult , Middle Aged , Atherosclerosis , Cholesterol, LDL , Foam Cells , Lipoproteins , Macrophages
20.
Radiol. bras ; 42(2): 109-113, mar.-abr. 2009. ilus, tab
Article in Portuguese | LILACS | ID: lil-513152

ABSTRACT

OBJETIVO: Descrever os aspectos tomográficos da tuberculose pulmonar primária manifestada inicialmente como consolidação lobar. MATERIAIS E MÉTODOS: O trabalho foi realizado no Hospital Municipal Jesus, Rio de Janeiro, RJ, no período de 2002 a 2006, avaliando-se retrospectivamente os aspectos tomográficos de quatro crianças de 3 a 14 meses de idade com tuberculose pulmonar primária manifestada inicialmente como consolidação lobar. RESULTADOS: O padrão radiológico mais frequente foi a consolidação lobar com calcificações, escavações e áreas de necrose de permeio, associada a abaulamento da cissura. Sinais de disseminação broncogênica e linfadenomegalia foram observados em todas elas. Consolidação de aspecto pseudotumoral, com efeito de massa, foi observada em um caso. CONCLUSÃO: Nos casos estudados observou-se que a tuberculose pulmonar primária manifestada como consolidação lobar apresenta imagens características à tomografia computadorizada, como escavações, áreas hipodensas e calcificações de permeio à consolidação. A associação com linfonodomegalias com centro necrótico e sinais de disseminação broncogênica reforçam o diagnóstico de tuberculose.


OBJECTIVE: To describe tomographic findings of lobar consolidation as early manifestation of primary pulmonary tuberculosis. MATERIALS AND METHODS: The present study was developed at Hospital Municipal Jesus, Rio de Janeiro, RJ, Brazil, in the period between 2002 and 2006, retrospectively evaluating tomographic findings in four children aged from 3 to 14 months with lobar consolidation as an early manifestation of primary pulmonary tuberculosis. RESULTS: The most frequently found radiological pattern was lobar consolidation with calcifications, cavitation and intermingle necrotic areas, associated with bulging fissure. Signs of bronchogenic dissemination and lymph node enlargement were observed in all of the four children. Consolidation with a pseudotumor aspect and masslike effect was observed in one case. CONCLUSION: The cases included in the present study have demonstrated that primary pulmonary tuberculosis manifested as lobar consolidation presents typical tomographic images such as cavitation, hypodense areas and calcifications intermingled with consolidation. The association with lymph node enlargement with central necrosis and signs of bronchogenic dissemination reinforce the diagnosis of tuberculosis.


Subject(s)
Humans , Male , Female , Infant , Mycobacterium Infections, Nontuberculous , Tuberculosis, Pulmonary , Tuberculosis, Pulmonary , Radiography, Thoracic , Retrospective Studies , Tomography, X-Ray Computed
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