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1.
Math Biosci Eng ; 21(1): 582-601, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303435

RESUMO

This paper introduces a solution to address the intricacy of the model employed in the deep learning-based diagnosis of musculoskeletal abnormalities and the limitations observed in the performance of a single deep learning network model. The proposed approach involves the integration of an improved EfficientNet-B2 model with MobileNetV2, resulting in the creation of FusionNet. First, EfficientNet-B2 is combined with coordinate attention (CA) to obtain CA-EfficientNet-B2. Furthermore, aiming to minimize the model parameter count, we further enhanced the mobile inverted residual bottleneck convolution module (MBConv) employed for feature extraction in EfficientNet-B2, resulting in the development of CA-MBC-EfficientNet-B2. Next, the features extracted from CA-MBC-EfficientNet-B2 and MobileNetV2 are fused. Finally, the final diagnosis of musculoskeletal abnormalities was performed by using fully connected layers. The experimental results demonstrate that, first, compared to EfficientNet-B2, CA-MBC-EfficientNet-B2 not only significantly improves the diagnostic performance of musculoskeletal abnormalities, it also reduces the parameter count and storage space by 17%. Moreover, as compared to other models, FusionNet demonstrates remarkable performance in the area of anomaly diagnosis, particularly on the elbow dataset, achieving a precision of 92.93%, an AUC of 93.89% and an accuracy of 87.10%.


Assuntos
Anormalidades Musculoesqueléticas , Humanos , Anormalidades Musculoesqueléticas/diagnóstico , Aprendizado Profundo
2.
Free Radic Biol Med ; 51(7): 1390-8, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21784147

RESUMO

The acute-phase protein serum amyloid A (SAA) is elevated during inflammation and may be deposited in atheroma where it promotes atherosclerosis. We investigated the proatherogenic effects of SAA on the vascular endothelium and their regulation by high-density lipoprotein (HDL). Exposure of human aortic endothelial cells (HAEC) to SAA (0.25-25µg/ml) decreased nitric oxide ((•)NO) synthesis/bioavailability, although the endothelial NO synthase monomer-to-dimer ratio was unaffected. SAA (10µg/ml) stimulated a Ca(2+) influx linked to apocynin-sensitive superoxide radical anion (O(2)(•-)) production. Gene expression for arginase-1, nuclear factor κB (NF-κB), interleukin-8, and tissue factor (TF) increased within 4h of SAA stimulation. Enzymatically active Arg-1/2 was detected in HAEC cultured with SAA for 24h. Therefore, in addition to modulating (•)NO bioavailability by stimulating O(2)(•-) production in the endothelium, SAA modulated vascular l-Arg bioavailability. SAA also diminished relaxation of preconstricted aortic rings induced by acetylcholine, and added superoxide dismutase restored the vascular response. Preincubation of HAEC with HDL (100 or 200, but not 50, µg/ml) before (not after) SAA treatment ameliorated the Ca(2+) influx and O(2)(•-) production; decreased TF, NF-κB, and Arg-1 gene expression; and preserved overall vascular function. Thus, SAA may promote endothelial dysfunction by modulating (•)NO and l-Arg bioavailability, and HDL pretreatment may be protective. The relative HDL to SAA concentrations may regulate the proatherogenic properties of SAA on the vascular endothelium.


Assuntos
Aorta/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Lipoproteínas HDL/uso terapêutico , Proteína Amiloide A Sérica/efeitos adversos , Superóxidos/antagonistas & inibidores , Animais , Aorta/metabolismo , Aorta/patologia , Arginase/genética , Arginase/metabolismo , Aterosclerose/metabolismo , Aterosclerose/patologia , Western Blotting , Cálcio/antagonistas & inibidores , Cálcio/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Expressão Gênica , Humanos , Inflamação/metabolismo , Inflamação/patologia , Lipoproteínas HDL/metabolismo , Lipoproteínas HDL/farmacologia , Masculino , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico/análise , Óxido Nítrico/metabolismo , Ratos , Ratos Wistar , Proteína Amiloide A Sérica/metabolismo , Proteína Amiloide A Sérica/farmacologia , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Tromboplastina/genética , Tromboplastina/metabolismo
3.
Clin Exp Pharmacol Physiol ; 37(11): 1049-54, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20659134

RESUMO

1. The relationship between inflammation, obesity-related proteins and tissue factor (TF), the major initiator of the extrinsic clotting cascade, is not well understood. We examined if basal and stimulated peripheral blood mononuclear cell (PBMC) TF-procoagulant activity (PCA) was higher in obese subjects and examined the effects of leptin, resistin and serum amyloid A (SAA). 2. PBMC from 12 obese (six male, aged 29±4years, body mass index 46.0±8.7kg/m(2) ) and 12 age- and sex-matched lean controls were cultured either unstimulated or stimulated by lipopolysaccharide (LPS; 10ρg/mL and 100ng/mL, for 4-16h) or SAA (1 ng/mL, 25ng/mL, 250ng/mL, for 4h). Separately, PBMC from lean subjects were cultured unstimulated with leptin (100ρg/mL, 1ng/mL, 10ng/mL, 100ng/mL, 1 µg/mL), resistin (0.1ng/mL, 1ng/mL, 10ng/mL, 100ng/mL) or leptin (100ng/mL) plus LPS (100ρg/mL). TF-PCA was determined by a 1-stage plasma recalcification assay. 3. Four-hour unstimulated PBMC TF-PCA was greater in the obese (90.4±16.5 vs 39.9±4.7mu TF/10(6) PBMC, P=0.01). After 4h stimulation with SAA or LPS the TF-PCA was similar. Unstimulated TF-PCA correlated with log serum high sensitivity C- reactive protein (hs-CRP) (r=0.42, P=0.04) and insulin (r=0.44, P=0.048), but not with log serum SAA (r=0.192, P=0.55). Physiological concentrations of leptin or resistin and leptin plus LPS did not increase TF-PCA in PBMC from lean subjects. 4. Basal PBMC TF-PCA is higher in the obese and is associated with serum hs-CRP. The obesity-related proteins SAA, leptin and resistin are unlikely to play a major role in increasing PBMC TF-PCA.


Assuntos
Leucócitos Mononucleares/metabolismo , Obesidade/sangue , Tromboplastina/biossíntese , Adulto , Estudos de Casos e Controles , Técnicas de Cultura de Células , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Leptina/farmacologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Lipopolissacarídeos/farmacologia , Masculino , Obesidade/complicações , Obesidade/imunologia , Obesidade/metabolismo , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Amiloide A Sérica/análise , Proteína Amiloide A Sérica/imunologia , Tromboplastina/imunologia , Trombose/sangue , Trombose/etiologia , Trombose/imunologia , Trombose/metabolismo
4.
Redox Rep ; 14(5): 187-96, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19843373

RESUMO

The acute-phase protein serum amyloid A (SAA) is a clinically useful marker of inflammation and associates strongly with increased risk of cardiovascular events. Chronically elevated SAA concentrations may contribute to physiological processes that lead to atherosclerosis, including endothelial dysfunction, an early and predictive event in the development of cardiovascular disease. Accumulating data suggest that SAA can be a direct mediator in the development and progression of atherogenesis and atherothrombosis. SAA may affect key events underlying acute coronary syndromes, including cholesterol transport, contribute to endothelial dysfunction, promote thrombosis, and enhance leukocyte trafficking and activation. This review summarizes the evidence supporting a role for SAA as a potential regulator of inflammation and endothelial dysfunction, which underlie the adverse outcomes that complicate coronary artery disease. The findings suggest that novel therapeutic strategies to reduce SAA levels and/or oppose the actions of SAA may have beneficial effects in patients with coronary artery disease.


Assuntos
Aterosclerose/metabolismo , Doença da Artéria Coronariana/metabolismo , Endotélio Vascular/patologia , Lipoproteínas HDL/fisiologia , Estresse Oxidativo/fisiologia , Proteína Amiloide A Sérica/fisiologia , Animais , Endotélio Vascular/metabolismo , Humanos , Lipoproteínas HDL/metabolismo , Proteína Amiloide A Sérica/metabolismo
5.
Atherosclerosis ; 207(2): 374-83, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19535079

RESUMO

OBJECTIVES: Serum amyloid A (SAA) is a biomarker of inflammation. Elevated blood levels in cardiovascular disease and local deposition in atheroma implies a role of SAA as a mediator rather than just a marker of inflammation. This study explored SAA-induced cytokine production and secretion by mononuclear cells. METHODS AND RESULTS: RT-PCR showed that SAA time-dependently induced cytokine mRNAs in peripheral blood mononuclear cells (PBMC) and THP-1 monocytoid cells, and dramatically increased IL-1beta, MCP-1, IL-6, IL-8, IL-10, GM-CSF, TNF, and MIP-1alpha secretion by PBMC to levels 28 to 25,000 fold above baseline, as measured with Bio-Plex kits; monocytes were the principle source. SAA induction of cytokines in monocyte-derived macrophages (MDM) was significantly higher than from monocytes from the same donors. SAA time-dependently induced transient and significant upregulation of NF-kappaB1 mRNA; inhibitor studies indicate that activation of NF-kappaB through the ERK1/2, p38 and JNK MAPKs and the PI3K pathway was involved. PBMC from 10 patients with coronary artery disease (CAD) spontaneously secreted higher levels of IL-6 and MIP-1alpha after 24h incubation than PBMC from normal controls, whereas SAA-induced levels of all cytokines were similar to controls. Aortic and coronary sinus sampling in 23 CAD patients indicated significant SAA release into the coronary circulation, not evident in 11 controls. CONCLUSIONS: SAA can increase monocyte and macrophage cytokine production, possibly at sites of atherosclerosis, thereby contributing to the pro-inflammatory state in coronary artery disease.


Assuntos
Doença da Artéria Coronariana/imunologia , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Linfócitos/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Proteína Amiloide A Sérica/metabolismo , Idoso , Estudos de Casos e Controles , Células Cultivadas , Doença da Artéria Coronariana/fisiopatologia , Circulação Coronária , Citocinas/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Linfócitos/enzimologia , Macrófagos/enzimologia , Masculino , Pessoa de Meia-Idade , Monócitos/enzimologia , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , RNA Mensageiro/metabolismo , Fatores de Tempo , Regulação para Cima
6.
J Immunol ; 183(1): 593-603, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19542470

RESUMO

Macrophages, cytokines, and matrix metalloproteinases (MMP) play important roles in atherogenesis. The Ca(2+)-binding protein S100A12 regulates monocyte migration and may contribute to atherosclerosis by inducing proinflammatory cytokines in macrophages. We found significantly higher S100A12 levels in sera from patients with coronary artery disease than controls and levels correlated positively with C-reactive protein. S100A12 was released into the coronary circulation from ruptured plaque in acute coronary syndrome, and after mechanical disruption by percutaneous coronary intervention in stable coronary artery disease. In contrast to earlier studies, S100A12 did not stimulate proinflammatory cytokine production by human monocytes or macrophages. Similarly, no induction of MMP genes was found in macrophages stimulated with S100A12. Because S100A12 binds Zn(2+), we studied some functional aspects that could modulate atherogenesis. S100A12 formed a hexamer in the presence of Zn(2+); a novel Ab was generated that specifically recognized this complex. By chelating Zn(2+), S100A12 significantly inhibited MMP-2, MMP-9, and MMP-3, and the Zn(2+)-induced S100A12 complex colocalized with these in foam cells in human atheroma. S100A12 may represent a new marker of this disease and may protect advanced atherosclerotic lesions from rupture by inhibiting excessive MMP-2 and MMP-9 activities by sequestering Zn(2+).


Assuntos
Aterosclerose/metabolismo , Doença das Coronárias/metabolismo , Proteínas S100/fisiologia , Adulto , Idoso , Aterosclerose/patologia , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Doença das Coronárias/patologia , Feminino , Humanos , Mediadores da Inflamação/sangue , Mediadores da Inflamação/fisiologia , Macrófagos/enzimologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz , Pessoa de Meia-Idade , Ruptura Espontânea/enzimologia , Ruptura Espontânea/metabolismo , Ruptura Espontânea/prevenção & controle , Proteínas S100/sangue , Proteína S100A12 , Zinco/fisiologia
7.
Atherosclerosis ; 202(2): 596-604, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18571179

RESUMO

AIMS: Elevated serum amyloid A (SAA) levels, like C-reactive protein (CRP), predict coronary events. Both induce monocyte tissue factor (TF), and peripheral blood mononuclear cells (PBMC) from patients with coronary artery disease (CAD) express higher TF in response to CRP. This study examined SAA induction of TF and tumour necrosis factor-alpha (TNF) in PBMC from patients with CAD and in monocytoid THP-1 cells. METHODS AND RESULTS: PBMC from 26 males with CAD (15 stable angina, SA, and 11 acute coronary syndromes, ACS) and 14 male controls were stimulated with SAA. SAA promoted up to six-fold increase in TF activity (recalcification assay) on PBMC from patients, associated with elevated TF mRNA and protein. PBMC responded optimally when monocytes were adherent. Unlike CRP, SAA induced TF and TNF in THP-1 cells. SAA-induced TNF was dose-dependently inhibited by HDL. PBMC from patients with ACS expressed more basal TF (257.4+/-46.8 mU/10(6) PBMC vs. 131.0+/-12.5 mU/10(6) PBMC, P=0.003), and greater SAA-induced TF than cells from controls, whereas no difference was found between SA and controls (ACS 2246+/-493, SA 1364+/-206, controls 1091+/-113 mU/10(6) PBMC, with SAA 250 ng/mL, P=0.002 ACS vs. controls across the dose range). Importantly, SAA-induced TNF levels (ELISA) were much higher in patients with ACS than SA or controls (ACS 211+/-41, SA 108+/-16, controls 73+/-11 pg/mL, with SAA 250 ng/mL, P=0.001 ACS vs. controls or P=0.013 ACS vs. SA across the dose range). SAA-induced TF and TNF correlated positively with serum SAA levels in CAD, but not controls. CONCLUSIONS: SAA is a prothrombotic and proinflammatory mediator in ACS which may contribute to atherogenesis and its complications.


Assuntos
Síndrome Coronariana Aguda/imunologia , Síndrome Coronariana Aguda/metabolismo , Proteína Amiloide A Sérica/metabolismo , Trombose/imunologia , Trombose/metabolismo , Idoso , Angina Pectoris/imunologia , Angina Pectoris/metabolismo , Proteína C-Reativa/metabolismo , Linhagem Celular , Células Cultivadas , HDL-Colesterol/metabolismo , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Proteína Amiloide A Sérica/farmacologia , Tromboplastina/genética , Tromboplastina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Vasculite/imunologia , Vasculite/metabolismo
8.
Scand J Gastroenterol ; 42(11): 1321-31, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17852869

RESUMO

OBJECTIVE: Various markers characterize the complex inflammatory processes seen in chronic inflammatory bowel disease (IBD) including calprotectin, a complex of two S100 proteins, which has been evaluated and validated as a faecal marker of inflammation. However, the systemic and mucosal expression patterns of calprotectin and related S100 proteins are not well characterized in this disease. The objective of this study was to assess serum and mucosal levels of calprotectin, S100A12 and soluble receptor for advanced glycation end products (sRAGE), a putative S100 ligand, in a paediatric population with IBD. MATERIAL AND METHODS: Children were enrolled at diagnosis of IBD, along with groups of children without IBD. Standard inflammatory markers and disease activity scores were collated. Calprotectin, S100A12 and sRAGE levels in serum and biopsy culture supernatants were measured by ELISA and tissue distribution of S100 proteins was investigated by immunohistochemistry. RESULTS: Serum and mucosal calprotectin and S100A12 levels were increased in children with IBD as compared with non-IBD controls. Serum calprotectin levels correlated with S100A12 levels and with disease activity scores in children with IBD. sRAGE levels were not increased in IBD. S100A8, S100A9 and S100A12 were abundantly expressed throughout the lamina propria and epithelium in inflamed mucosa. In contrast, these proteins were present in the lamina propria, but not the epithelium, in non-inflamed mucosa. CONCLUSIONS: Serum calprotectin and S100A12 are increased in children with IBD and indicate disease activity. Elevated levels of these proteins are present in the colonic mucosa and may contribute to the pathogenesis of IBD. Furthermore, an imbalance between sRAGE and S100A12 may contribute to inflammatory changes present in IBD.


Assuntos
Doenças Inflamatórias Intestinais/patologia , Complexo Antígeno L1 Leucocitário/análise , Proteínas S100/análise , Adolescente , Biópsia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Epitélio/química , Feminino , Humanos , Mucosa Intestinal/química , Complexo Antígeno L1 Leucocitário/sangue , Masculino , Mucosa/química , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/sangue , Proteínas S100/sangue , Proteína S100A12
9.
J Immunol ; 178(3): 1852-60, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17237436

RESUMO

C-reactive protein (CRP) and serum amyloid A (SAA) increase in the blood of patients with inflammatory conditions and CRP-induced monocyte tissue factor (TF) may contribute to inflammation-associated thrombosis. This study demonstrates that SAA is a potent and rapid inducer of human monocyte TF. SAA induced TF mRNA in PBMC within 30 min and optimal procoagulant activity within 4 h, whereas CRP (25 mug/ml)-induced activity was minimal at this time. Unlike CRP, SAA did not synergize with LPS. Procoagulant activity was inhibited by anti-TF and was dependent on factors VII and X, and TF Ag levels were elevated on CD14(+) monocytes. Responses were optimal with lymphocytes, although these were not obligatory. Inhibitor studies indicate activation of NF-kappaB through the ERK1/2 and p38 MAPK pathways; the cyclo-oxygenase pathway was not involved. SAA-induced TF was partially inhibited by high-density lipoprotein, but not by low-density lipoprotein or by apolipoprotein A-I. SAA is a ligand for the receptor for advanced glycation end products (RAGE), and TF generation was suppressed by approximately 50% by a RAGE competitor, soluble RAGE, and by approximately 85% by anti-RAGE IgG. However, another RAGE ligand, high mobility group box-1 protein, capable of inducing monocyte chemotactic protein-1 mRNA in 2 h, did not induce TF within 24 h. Cross-linking studies confirmed SAA binding to soluble RAGE. Elevated SAA is a marker of disease activity in patients with rheumatoid arthritis, and PBMC from patients with rheumatoid arthritis were more sensitive to SAA than normals, suggesting a new link between inflammation and thrombosis.


Assuntos
Monócitos/metabolismo , Proteína Amiloide A Sérica/fisiologia , Tromboplastina/genética , Idoso , Artrite Reumatoide/sangue , Proteína C-Reativa , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Humanos , Lipoproteínas/farmacologia , Masculino , Pessoa de Meia-Idade , NF-kappa B/metabolismo , RNA Mensageiro , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/metabolismo , Proteína Amiloide A Sérica/metabolismo , Transdução de Sinais , Trombofilia
10.
J Rheumatol ; 32(7): 1224-31, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15996056

RESUMO

OBJECTIVE: To determine the relationship between plasma C-reactive protein (CRP) concentrations and monocyte tissue factor (TF) expression induced in vitro by combinations of CRP, ss2-glycoprotein I (ss2-GPI), and lipopolysaccharide (LPS). METHODS: Peripheral blood mononuclear cells (PBMC) from 26 healthy individuals and 31 patients with inflammatory rheumatic diseases (IRD) were cultured with combinations of CRP, purified or recombinant ss2-GPI, and LPS and monocyte TF procoagulant activity, TF antigen, and TF mRNA were measured. Results were examined against plasma CRP levels. RESULTS: Monocytes from patients with IRD expressed significantly more TF when stimulated with CRP compared to normal monocytes (p = 0.002). An incremental positive correlation was observed between plasma CRP levels and TF induced by CRP or ss2-GPI. Significantly more TF was induced with CRP combined with ss2-GPI, compared to ss2-GPI alone, either with costimulation or CRP priming. Conversely, when combined with LPS, ss2-GPI suppressed TF induction in a dose-dependent manner on normal PBMC but not on PBMC from patients with IRD. The loss of suppression correlated strongly with plasma CRP levels. CONCLUSION: This study shows a remarkably consistent effect of CRP on monocyte TF expression. Systemic inflammation associated with elevated plasma CRP conferred a phenotype on PBMC, whereby incremental priming with respect to TF expression (induced by CRP itself or ss2-GPI) was apparent, and ss2-GPI-mediated inhibition of TF expression induced by LPS was incrementally lost. CRP regulation of monocyte TF could contribute to the higher than expected atherosclerotic vascular disease seen in patients with IRD.


Assuntos
Artrite Reumatoide/imunologia , Proteína C-Reativa/imunologia , Monócitos/imunologia , Tromboplastina/metabolismo , Adulto , Arteriosclerose/imunologia , Arteriosclerose/metabolismo , Artrite Reumatoide/metabolismo , Proteína C-Reativa/metabolismo , Células Cultivadas , Feminino , Glicoproteínas/metabolismo , Humanos , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Monócitos/citologia , Monócitos/metabolismo , Regulação para Cima/imunologia , beta 2-Glicoproteína I
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