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1.
J Korean Soc Radiol ; 85(3): 566-578, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38873383

RESUMO

Purpose: This study investigated whether the respiratory phase during pleural puncture in CT-guided percutaneous transthoracic needle biopsy (PTNB) affects complications. Materials and Methods: We conducted a retrospective review of 477 lung biopsy CT scans performed during free breathing. The respiratory phases during pleural puncture were determined based on the table position of the targeted nodule using CT scans obtained during free breathing. We compared the rates of complications among the inspiratory, mid-, and expiratory respiratory phases. Logistic regression analysis was performed to control confounding factors associated with pneumothorax. Results: Among the 477 procedures, pleural puncture was performed during the expiratory phase in 227 (47.6%), during the mid-phase in 108 (22.6%), and during the inspiratory phase in 142 (29.8%). The incidence of pneumothorax was significantly lower in the expiratory puncture group (40/227, 17.6%; p = 0.035) and significantly higher in the mid-phase puncture group (31/108, 28.7%; p = 0.048). After controlling for confounding factors, expiratory-phase puncture was found to be an independent protective factor against pneumothorax (odds ratio = 0.571; 95% confidence interval = 0.360-0.906; p = 0.017). Conclusion: Our findings suggest that pleural puncture during the expiratory phase may reduce the risk of pneumothorax during image guided PTNB.

2.
Acta Radiol ; 65(6): 654-662, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38623647

RESUMO

BACKGROUND: Post-contrast T1-Sampling Perfection with Application-optimized Contrasts using different flip angle Evolutions (SPACE) is the preferred 3D T1 spin-echo sequence for evaluating brain metastases, regardless of the prolonged scan time. PURPOSE: To evaluate the application of accelerated post-contrast T1-SPACE with iterative denoising (ID) for intracranial enhancing lesions in oncologic patients. MATERIAL AND METHODS: For evaluation of intracranial lesions, 108 patients underwent standard and accelerated T1-SPACE during the same imaging session. Two neuroradiologists evaluated the overall image quality, artifacts, degree of enhancement, mean contrast-to-noise ratiolesion/parenchyma, and number of enhancing lesions for standard and accelerated T1-SPACE without ID. RESULTS: Although there was a significant difference in the overall image quality and mean contrast-to-noise ratiolesion/parenchyma between standard and accelerated T1-SPACE without ID and accelerated SPACE with and without ID, there was no significant difference between standard and accelerated T1-SPACE with ID. Accelerated T1-SPACE showed more artifacts than standard T1-SPACE; however, accelerated T1-SPACE with ID showed significantly fewer artifacts than accelerated T1-SPACE without ID. Accelerated T1-SPACE without ID showed a significantly lower number of enhancing lesions than standard- and accelerated T1-SPACE with ID; however, there was no significant difference between standard and accelerated T1-SPACE with ID, regardless of lesion size. CONCLUSION: Although accelerated T1-SPACE markedly decreased the scan time, it showed lower overall image quality and lesion detectability than the standard T1-SPACE. Application of ID to accelerated T1-SPACE resulted in comparable overall image quality and detection of enhancing lesions in brain parenchyma as standard T1-SPACE. Accelerated T1-SPACE with ID may be a promising replacement for standard T1-SPACE.


Assuntos
Artefatos , Neoplasias Encefálicas , Meios de Contraste , Estudos de Viabilidade , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Feminino , Estudos Retrospectivos , Masculino , Pessoa de Meia-Idade , Idoso , Imageamento por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Razão Sinal-Ruído , Idoso de 80 Anos ou mais , Aumento da Imagem/métodos
3.
J Korean Soc Radiol ; 85(1): 197-203, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38362399

RESUMO

Tuberculous pericarditis is an extrapulmonary manifestation of tuberculosis that is most commonly associated with pericardial thickening, effusion, and calcification. We present a case of tuberculous pericarditis mimicking a malignant pericardial tumor in a 77-year-old male. CT revealed an irregular and nodular pericardial thickening. MRI revealed high signal intensity on T1-weighted fat-suppressed images and peripheral rim enhancement after gadolinium administration. MRI can be helpful in determining the differential diagnoses in cases of tuberculous pericarditis with nonspecific imaging findings.

4.
Eur Radiol ; 33(9): 6145-6156, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37059905

RESUMO

OBJECTIVES: To develop and validate a nomogram based on MRI features for predicting iNPH. METHODS: Patients aged ≥ 60 years (clinically diagnosed with iNPH, Parkinson's disease, or Alzheimer's disease or healthy controls) who underwent MRI including three-dimensional T1-weighted volumetric MRI were retrospectively identified from two tertiary referral hospitals (one hospital for derivation set and the other for validation set). Clinical and imaging features for iNPH were assessed. Deep learning-based brain segmentation software was used for 3D volumetry. A prediction model was developed using logistic regression and transformed into a nomogram. The performance of the nomogram was assessed with respect to discrimination and calibration abilities. The nomogram was internally and externally validated. RESULTS: A total of 452 patients (mean age ± SD, 73.2 ± 6.5 years; 200 men) were evaluated as the derivation set. One hundred eleven and 341 patients were categorized into the iNPH and non-iNPH groups, respectively. In multivariable analysis, high-convexity tightness (odds ratio [OR], 35.1; 95% CI: 4.5, 275.5), callosal angle < 90° (OR, 12.5; 95% CI: 3.1, 50.0), and normalized lateral ventricle volume (OR, 4.2; 95% CI: 2.7, 6.7) were associated with iNPH. The nomogram combining these three variables showed an area under the curve of 0.995 (95% CI: 0.991, 0.999) in the study sample, 0.994 (95% CI: 0.990, 0.998) in the internal validation sample, and 0.969 (95% CI: 0.940, 0.997) in the external validation sample. CONCLUSION: A brain morphometry-based nomogram including high-convexity tightness, callosal angle < 90°, and normalized lateral ventricle volume can help accurately estimate the probability of iNPH. KEY POINTS: • The nomogram with MRI findings (high-convexity tightness, callosal angle, and normalized lateral ventricle volume) helped in predicting the probability of idiopathic normal-pressure hydrocephalus. • The nomogram may facilitate the prediction of idiopathic normal-pressure hydrocephalus and consequently avoid unnecessary invasive procedures such as the cerebrospinal fluid tap test, drainage test, and cerebrospinal fluid shunt surgery.


Assuntos
Doença de Alzheimer , Hidrocefalia de Pressão Normal , Masculino , Humanos , Idoso , Nomogramas , Estudos Retrospectivos , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
5.
Neuroradiology ; 61(7): 747-755, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30684114

RESUMO

PURPOSE: To evaluate the diagnostic performance, image quality, artifacts, and radiation doses of virtual non-contrast (VNC) images, relative to true non-contrast (TNC) images, in patients with surgically clipped aneurysms. METHODS: Seventy-six patients who underwent unenhanced computed tomography (CT) and dual-energy (DE)-CT angiography after surgical clipping of 85 intracranial aneurysms were included in the study. Diagnostic performances of VNC and TNC images were compared with respect to sensitivity, specificity, and positive and negative predictive values. The results of quantitative and qualitative analyses were compared between VNC and TNC images. Radiation doses were also compared between VNC and TNC images. RESULTS: Diagnostic performance of VNC images was lower than that of TNC images; however, addition of contrast-enhanced images improved diagnostic performance. Image noise and mean attenuation of VNC images were significantly higher than those of TNC images in the centrum semiovale, cerebellum, and pons. The quality of VNC images was excellent or sufficient (85.5% for observer 1, 85.5% for observer 2), and complete acceptance of VNC images was achieved in 64.5% for observer 1 and in 71.0% for observer 2; however, the addition of contrast-enhanced images increased the level of acceptance (92.0% for observer 1, 90.9% for observer 2). Clip artifacts were significantly lower in VNC images than in TNC images. CT dose index, dose-length product, and effective dose were significantly lower without TNC images. CONCLUSION: VNC images showed lower diagnostic performance and image quality, and higher image noise than TNC images; however, VNC images could reduce clip artifacts and radiation doses.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Meios de Contraste , Feminino , Humanos , Aneurisma Intracraniano/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
6.
Blood ; 101(9): 3534-42, 2003 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-12511421

RESUMO

Rosmarinic acid (RosA) is a hydroxylated compound frequently found in herbal plants and is mostly responsible for anti-inflammatory and antioxidative activity. Previously, we observed that RosA inhibited T-cell antigen receptor (TCR)- induced interleukin 2 (IL-2) expression and subsequent T-cell proliferation in vitro. In this study, we investigated in detail inhibitory mechanism of RosA on TCR signaling, which ultimately activates IL-2 promoter by activating transcription factors, such as nuclear factor of activated T cells (NF-AT) and activating protein-1 (AP-1). Interestingly, RosA inhibited NF-AT activation but not AP-1, suggesting that RosA inhibits Ca(2+)-dependent signaling pathways only. Signaling events upstream of NF-AT activation, such as the generation of inositol 1,4,5-triphosphate and Ca(2+) mobilization, and tyrosine phosphorylation of phospholipase C-gamma 1 (PLC-gamma 1) were strongly inhibited by RosA. Tyrosine phosphorylation of PLC-gamma 1 is largely dependent on 3 kinds of protein tyrosine kinases (PTKs), ie, Lck, ZAP-70, and Itk. We found that RosA efficiently inhibited TCR-induced tyrosine phosphorylation and subsequent activation of Itk but did not inhibit Lck or ZAP-70. ZAP-70-dependent signaling pathways such as the tyrosine phosphorylation of LAT and SLP-76 and serine/threonine phosphorylation of mitogen-activated protein kinases (MAPKs) were intact in the presence of RosA, confirming that RosA suppresses TCR signaling in a ZAP-70-independent manner. Therefore, we conclude that RosA inhibits TCR signaling leading to Ca(2+) mobilization and NF-AT activation by blocking membrane-proximal events, specifically, the tyrosine phosphorylation of inducible T cells kinase (Itk) and PLC-gamma 1.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Anti-Inflamatórios não Esteroides/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Cinamatos/farmacologia , Inibidores Enzimáticos/farmacologia , Células Jurkat/efeitos dos fármacos , Proteínas de Membrana , Proteínas Nucleares , Proteínas Tirosina Quinases/antagonistas & inibidores , Receptores de Antígenos de Linfócitos T/efeitos dos fármacos , Fosfolipases Tipo C/antagonistas & inibidores , Animais , Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Depsídeos , Ativação Enzimática/efeitos dos fármacos , Proteína Adaptadora GRB2 , Humanos , Células Jurkat/enzimologia , Células Jurkat/imunologia , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Muromonab-CD3/farmacologia , Fatores de Transcrição NFATC , Fosfolipase C gama , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Tirosina Quinases/fisiologia , Proteínas/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Fatores de Transcrição/metabolismo , Proteína-Tirosina Quinase ZAP-70 , Ácido Rosmarínico
7.
Nephron ; 91(3): 406-15, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12119470

RESUMO

BACKGROUND/AIMS: Increased susceptibility of the kidney to acute renal failure (ARF) in the setting of sepsis even in the absence of systemic hypotension is well known. In the hypothesis that the proinflammatory cytokines and lipopolysaccharide (LPS) in gram-negative sepsis can directly cause renal tubular cell apoptosis via Fas- and caspase-mediated pathways, we examined apoptosis and Fas, Fas ligand, FADD expression, as well as PARP cleavage in cultured human proximal tubular cells under the cytokine and LPS-stimulated conditions. METHODS: HK-2 cell, immortalized human proximal tubular cell lines, were treated with 5 and 30 ng/ml of tumor necrosis factor-alpha (TNF-alpha), 5 and 20 ng/ml of interleukin-1beta (IL-1beta) and 30 ng/ml LPS for 24 h. Fas expression was examined by RT-PCR and Fas ligand, Fas-associated protein with death domain (FADD) and poly ADP ribose polymerase (PARP) cleavage were examined by Western blot analysis. Apoptosis was assessed by flow cytometer using Annexin V-FITC and propidium iodide (PI) staining and also by terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) methods. RESULTS: Fas mRNA expression (ratio of Fas/L-19) increased in the TNF-alpha 5, 30 ng/ml and LPS treated group (p < 0.01, p < 0.01, p = 0.02), but there was no difference between the low- and high-dose TNF-alpha groups. Fas ligand protein expression did not increase in the low-dose TNF-alpha treated group, but it increased significantly in the high-dose TNF-alpha treated group (p < 0.01), IL-1beta- and LPS-treated groups (p < 0.01, p = 0.01, p < 0.01, p = 0.02). The intracellular adaptor protein, FADD expression also increased significantly in the high-dose TNF-alpha- and IL-beta-treated groups (p = 0.04, p = 0.04), but in the low-dose TNF-alpha and IL-beta treated group, it did not show statistically significant differences. In the LPS group, FADD expression also showed an increased tendency, but it was not statistically significant (p = 0.09). Western blot for PARP, a DNA repair enzyme mainly cleaved by caspase 3, showed increased 89- and 24-kD PARP cleavage products in TNF-alpha, IL-1beta and LPS treated cells. The degree of apoptosis examined by DNA fragmentation and translocation of membrane phosphatidyl serine significantly increased in cytokines and LPS treated groups. CONCLUSION: These results suggest that Fas- and caspase-mediated apoptosis of tubular cells by inflammatory cytokines and LPS can be one of the possible mechanisms of renal dysfunction in endotoxemia.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Apoptose/fisiologia , Interleucina-1/farmacologia , Túbulos Renais/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Receptor fas/metabolismo , Apoptose/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Linhagem Celular , Proteína Ligante Fas , Proteína de Domínio de Morte Associada a Fas , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Interleucina-1/imunologia , Interleucina-1/metabolismo , Túbulos Renais/citologia , Túbulos Renais/metabolismo , Glicoproteínas de Membrana/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Receptor fas/genética
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