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1.
Biosens Bioelectron ; 256: 116260, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38613935

RESUMEN

Various bioelectronic noses have been recently developed for mimicking human olfactory systems. However, achieving direct monitoring of gas-phase molecules remains a challenge for the development of bioelectronic noses due to the instability of receptor and the limitations of its surrounding microenvironment. Here, we report a MXene/hydrogel-based bioelectronic nose for the sensitive detection of liquid and gaseous hexanal, a signature odorant from spoiled food. In this study, a conducting MXene/hydrogel structure was formed on a sensor via physical adsorption. Then, canine olfactory receptor 5269-embedded nanodiscs (cfOR5269NDs) which could selectively recognize hexanal molecules were embedded in the three-dimensional (3D) MXene/hydrogel structures using glutaraldehyde as a linker. Our MXene/hydrogel-based bioelectronic nose exhibited a high selectivity and sensitivity for monitoring hexanal in both liquid and gas phases. The bioelectronic noses could sensitively detect liquid and gaseous hexanal down to 10-18 M and 6.9 ppm, and they had wide detection ranges of 10-18 - 10-6 M and 6.9-32.9 ppm, respectively. Moreover, our bioelectronic nose allowed us to monitor hexanal levels in fish and milk. In this respect, our MXene/hydrogel-based bioelectronic nose could be a practical strategy for versatile applications such as food spoilage assessments in both liquid and gaseous systems.


Asunto(s)
Técnicas Biosensibles , Nariz Electrónica , Técnicas Biosensibles/métodos , Animales , Gases/química , Gases/análisis , Aldehídos/química , Análisis de los Alimentos/instrumentación , Análisis de los Alimentos/métodos , Perros , Receptores Odorantes/química , Humanos , Leche/microbiología , Leche/química , Diseño de Equipo , Odorantes/análisis
2.
Quant Imaging Med Surg ; 14(4): 2993-3005, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38617165

RESUMEN

Background: It is crucial to distinguish unstable from stable intracranial aneurysms (IAs) as early as possible to derive optimal clinical decision-making for further treatment or follow-up. The aim of this study was to investigate the value of a deep learning model (DLM) in identifying unstable IAs from computed tomography angiography (CTA) images and to compare its discriminatory ability with that of a conventional logistic regression model (LRM). Methods: From August 2011 to May 2021, a total of 1,049 patients with 681 unstable IAs and 556 stable IAs were retrospectively analyzed. IAs were randomly divided into training (64%), internal validation (16%), and test sets (20%). Convolutional neural network (CNN) analysis and conventional logistic regression (LR) were used to predict which IAs were unstable. The area under the curve (AUC), sensitivity, specificity and accuracy were calculated to evaluate the discriminating ability of the models. One hundred and ninety-seven patients with 229 IAs from Banan Hospital were used for external validation sets. Results: The conventional LRM showed 11 unstable risk factors, including clinical and IA characteristics. The LRM had an AUC of 0.963 [95% confidence interval (CI): 0.941-0.986], a sensitivity, specificity and accuracy on the external validation set of 0.922, 0.906, and 0.913, respectively, in predicting unstable IAs. In predicting unstable IAs, the DLM had an AUC of 0.771 (95% CI: 0.582-0.960), a sensitivity, specificity and accuracy on the external validation set of 0.694, 0.929, and 0.782, respectively. Conclusions: The CNN-based DLM applied to CTA images did not outperform the conventional LRM in predicting unstable IAs. The patient clinical and IA morphological parameters remain critical factors for ensuring IA stability. Further studies are needed to enhance the diagnostic accuracy.

3.
J Agric Food Chem ; 71(20): 7847-7857, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37170887

RESUMEN

In this work, broad-spectrum aptamers for organophosphorus pesticides (OPs) were obtained by alternate target systematic evolution of ligands by exponential enrichment screening. The secondary and tertiary structure analyses of the aptamer inferred that the neck-loop structure formed a G-triplex structure with the target. In addition, optimization of the sheared aptamer resulted in a stronger affinity (Kd = 86.74 nM), which was increased by 2 orders of magnitude compared to similar aptamers. A novel electrochemical biosensor was prepared by modifying an aptamer labeled with an electroactive substance (methylene blue) on the surface of nanoporous carbon containing Fe-Co (Fe-Co/NPC). When a target bound to the aptamer, a G-triplex structure was formed close to the electrode surface. The aptamer phosphate backbone labeled with methylene blue enhanced the electron-transfer efficiency and resulted in signal changes. The biosensor exhibited an excellent sensitivity (7.32 fM) and a wide detection range (1 × 10-13 to 1 × 10-3 M) for OPs under optimal conditions, enabling simultaneous detection of multiple OPs in vegetables.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanoporos , Plaguicidas , Carbono , Compuestos Organofosforados/análisis , Aptámeros de Nucleótidos/química , Plaguicidas/química , Azul de Metileno , Técnicas Biosensibles/métodos , Límite de Detección , Técnicas Electroquímicas
4.
J Hazard Mater ; 440: 129707, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35986944

RESUMEN

For the visual detection of four organophosphorus pesticides (OPs), a colorimetric aptasensor was developed based on aptamer-mediated bimetallic metal-organic frameworks (MOFs) nano-polymers. Fe-Co magnetic nanoparticles (MNPs) and Fe-N-C nanozymes were prepared based on pyrolytic reaction, and were labeled with broad spectrum aptamers and complementary chains of organophosphorus pesticides respectively. The hybridization of aptamers and complementary chains led to the formation of nano-polymers. In the presence of target pesticides, they competed with complementary chains for aptamers on Fe-Co MNPs, resulting in a large number of Fe-N-C nanozymes signal labels being released into the supernatant. Fe-N-C nanozymes showed similar activity to peroxidase and catalyzed the 3,3',5,5'-tetramethylbenzidine-hydrogen peroxide (TMB-H2O2) color system to turn the solution blue-green under mild conditions. The magnetic probes had good selectivity and sensitivity, and were easily separated by magnetic absorption. The sensor functioned well under optimal conditions, demonstrating good stability and specificity for four pesticides: phorate, profenofos, isocarbophos and omethoate, and the detection limits of four pesticides were as low as 0.16 ng/mL, 0.16 ng/mL, 0.03 ng/mL and 1.6 ng/mL respectively, and the recovery rate of OPs residue in vegetable samples was satisfactory. The work described here provided a simple, rapid and sensitive way to construct a biosensor.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Estructuras Metalorgánicas , Plaguicidas , Aptámeros de Nucleótidos/química , Colorimetría/métodos , Peróxido de Hidrógeno , Límite de Detección , Estructuras Metalorgánicas/química , Compuestos Organofosforados , Peroxidasas , Plaguicidas/análisis , Forato
5.
Cancer Res ; 82(9): 1789-1802, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35502544

RESUMEN

The RNA N6-methyladenosine (m6A) writer methyltransferase-like 3 (METTL3) is upregulated in many types of cancer and promotes cancer progression by increasing expression of several oncogenes. Therefore, a better understanding of the mechanisms regulating METTL3 expression and the key targets of METTL3 in cancer cells could provide new therapeutic targets. In this study, we found that activated JNK signaling is associated with increased METTL3 expression in bladder cancer. Knockdown of JNK1 or administration of a JNK inhibitor impaired the binding of c-Jun with the METTL3 promoter, thereby decreasing the expression of METTL3 and global RNA m6A levels. Moreover, RNA m6A sequencing indicated enrichment of m6A in the 3'-UTR of immune checkpoint PD-L1 mRNA, which could be recognized by the m6A reader IGF2BP1 to mediate RNA stability and expression levels of PD-L1. Inhibition of JNK signaling suppressed m6A abundance in PD-L1 mRNA, leading to decreased PD-L1 expression. Functionally, METTL3 was essential for bladder cancer cells to resist the cytotoxicity of CD8+ T cells by regulating PD-L1 expression. Additionally, JNK signaling contributed to tumor immune escape in a METTL3-dependent manner both in vitro and in vivo. These data reveal the JNK/METTL3 axis as a mechanism of aberrant m6A modification and immune regulation in bladder cancer. SIGNIFICANCE: The identification of a novel m6A-dependent mechanism underlying immune system evasion by bladder cancer cells reveals JNK signaling as a potential target for bladder cancer immunotherapy.


Asunto(s)
Neoplasias de la Vejiga Urinaria , Adenosina/metabolismo , Antígeno B7-H1/genética , Femenino , Humanos , Masculino , Glicoproteínas de Membrana , Metiltransferasas/genética , Metiltransferasas/metabolismo , Proteína Quinasa 8 Activada por Mitógenos , Proteínas del Tejido Nervioso , ARN Mensajero/genética , ARN Mensajero/metabolismo , Neoplasias de la Vejiga Urinaria/patología
6.
Front Oncol ; 11: 683869, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34595106

RESUMEN

OBJECTIVE: To determine whether contrast-enhanced computed tomography (CT) can promote the identification of malignant and benign distal biliary strictures (DBSs) compared to the use of magnetic resonance cholangiopancreatography (MRCP) alone and to identify imaging findings of malignant DBSs. MATERIALS AND METHODS: A total of 168 consecutive patients with confirmed DBSs were reviewed. MRCP alone and MRCP combined with CT images were blindly analyzed by two radiologists (e.g., stricture pattern, margins), and malignant or benign DBSs were identified based on surgical findings, endoscopy findings, or follow-up. The diagnostic accuracy of the two reviewers using MRCP alone and MRCP combined with CT were evaluated. MRCP and CT features of malignant and benign DBSs were compared using multiple logistic regression analysis to identify independent malignant risk factors. RESULTS: MRCP combined with CT examination could improve the diagnostic accuracy, which increased from 70.2% to 81.5% in Doctor A and from 85.1% to 89.3% in Doctor B. The multiple logistic regression model revealed that stricture length [odds ratio (OR) 1.070, P=0.016], angle of the DBS (OR 1.061, P<0.001), double duct sign (OR 4.312, P=0.003) and low density in the arterial phase (OR 0.319, P=0.018) were associated with malignant DBS. A scoring model incorporating these four factors was established; at a threshold value of 1.75, and the sensitivity and specificity for the detection of malignant DBSs were 73.5 and 85.9%, respectively. CONCLUSIONS: Compared to the use of MRCP alone, MRCP combined with contrast-enhanced CT can improve the accuracy of DBS diagnosis. The scoring model accurately predicts malignant DBSs and helps make treatment decisions.

7.
Front Oncol ; 11: 756216, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34692547

RESUMEN

OBJECTIVES: To develop and validate an MR radiomics-based nomogram to predict the presence of MVI in patients with solitary HCC and further evaluate the performance of predictors for MVI in subgroups (HCC ≤ 3 cm and > 3 cm). MATERIALS AND METHODS: Between May 2015 and October 2020, 201 patients with solitary HCC were analysed. Radiomic features were extracted from precontrast T1WI, arterial phase, portal venous phase, delayed phase and hepatobiliary phase images in regions of the intratumoral, peritumoral and their combining areas. The mRMR and LASSO algorithms were used to select radiomic features related to MVI. Clinicoradiological factors were selected by using backward stepwise regression with AIC. A nomogram was developed by incorporating the clinicoradiological factors and radiomics signature. In addition, the radiomic features and clinicoradiological factors related to MVI were separately evaluated in the subgroups (HCC ≤ 3 cm and > 3 cm). RESULTS: Histopathological examinations confirmed MVI in 111 of the 201 patients (55.22%). The radiomics signature showed a favourable discriminatory ability for MVI in the training set (AUC, 0.896) and validation set (AUC, 0.788). The nomogram incorporating peritumoral enhancement, tumour growth type and radiomics signature showed good discrimination in the training (AUC, 0.932) and validation sets (AUC, 0.917) and achieved well-fitted calibration curves. Subgroup analysis showed that tumour growth type was a predictor for MVI in the HCC ≤ 3 cm cohort and peritumoral enhancement in the HCC > 3 cm cohort; radiomic features related to MVI varied between the HCC ≤ 3 cm and HCC > 3 cm cohort. The performance of the radiomics signature improved noticeably in both the HCC ≤ 3 cm (AUC, 0.953) and HCC > 3 cm cohorts (AUC, 0.993) compared to the original training set. CONCLUSIONS: The preoperative nomogram integrating clinicoradiological risk factors and the MR radiomics signature showed favourable predictive efficiency for predicting MVI in patients with solitary HCC. The clinicoradiological factors and radiomic features related to MVI varied between subgroups (HCC ≤ 3 cm and > 3 cm). The performance of radiomics signature for MVI prediction was improved in both the subgroups.

8.
Quant Imaging Med Surg ; 11(9): 4115-4124, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34476192

RESUMEN

BACKGROUND: The progression of an unruptured intracranial aneurysm (UIA) is associated with a higher rupture risk. The aim of this study was to identify the risk factors for the progression of UIAs among Chinese adults and compare them with the ELAPSS (Earlier subarachnoid hemorrhage, IA Location, Age, Population, IA Size and Shape) score. METHODS: Four hundred thirty-eight consecutive patients with 491 UIAs were followed and reviewed retrospectively from August 2011 to November 2019. Follow-up images of the UIAs were used to determine changes in IA size and shape. Patients and IAs were divided into non-progression and progression groups. In addition to the clinical characteristics of the patients, the features of the IAs (e.g., size and shape) were evaluated by computed tomography angiography (CTA) or magnetic resonance angiography (MRA). Independent risk factors for UIA progression were studied using multiple Cox proportional hazards regression analysis. In addition, the diagnostic value of the ELAPSS score for the prediction of UIA progression was calculated. RESULTS: Seventy-two IAs in 68 patients progressed during a mean follow-up time of 24.2±19.68 months. IAs located at the bifurcation [odds ratio (OR) 2.600], with an irregular shape (OR 2.981) or having a high aspect ratio (AR, OR 2.430) were correlated with progression. Based on these three factors, the threshold value of our predictive score was 0.5, and the area under the curve (AUC), sensitivity and specificity were 0.756, 93.1% and 40.6%, respectively, while the AUC, sensitivity and specificity of the ELAPSS score were 0.711, 55.6%, and 75.2%, respectively. CONCLUSIONS: IAs located at the bifurcation, with an irregular shape and with an elevated AR are risk factors for UIA progression in the Chinese population. Our predictive score is of great value in predicting the risk of UIA progression.

9.
Front Endocrinol (Lausanne) ; 11: 603279, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33362718

RESUMEN

Background: Previous studies have found that women with polycystic ovary syndrome (PCOS) have some degree of brain function change as well as cognitive function and emotions, such as poor executive functioning and memory, anxiety and depressive symptoms. However, the neurobiological mechanisms underlying these alterations have not yet been clarified. Method: Fasting serum hormone testing, neuropsychological testing and resting-state magnetic resonance imaging (rs-fMRI) were performed in 41 women with newly diagnosed PCOS and 41 healthy controls matched by age and education during their 2-5 days of menstrual period. Analysis of the amplitude of low-frequency fluctuation (ALFF) was used to calculate the seed points. Then, the functional connectivity (FC) values between these abnormal seed points and other voxels in the whole brain were calculated. Finally, the correlations among clinical indexes, neuropsychological evaluation scores, and neuroimaging data were analyzed. Results: Compared with the control group, the PCOS group showed higher luteinizing hormone (LH) and serum insulin levels, worse sleep quality, increased depressive and anxiety state scores, and memory and executive function impairments. Pearson's correlation analysis showed that the decreased ALFF value in the left middle frontal gyrus (MFG.L), which is related to poor executive performance and depressive disorders, was negatively correlated with the plasma insulin level in subjects with insulin resistance. Furthermore, the increased FC strength between the MFG.L and left inferior frontal gyrus (IFG.L) was positively correlated with the serum testosterone level. The enhanced FC strength between the left posterior cingulate gyrus (PCG.L) and triangular part of the left inferior frontal gyrus (IFGtriang.L) was negatively correlated with the plasma LH level. When use the right middle occipital gyrus (MOG.R) as the seed point, the FC strength with the right inferior occipital gyrus (IOG.R), which is associated with impaired memory, was decreased. Conclusion: The ALFF and FC results elucidated brain functional abnormalities at the regional and network levels in women with PCOS, while correlation analyses simultaneously demonstrated that these alterations were associated with serum hormones and cognitive function. These results may provide useful information regarding the potential mechanisms of cognitive impairment and emotional changes in this population.


Asunto(s)
Metabolismo Basal , Mapeo Encefálico/métodos , Encéfalo/patología , Disfunción Cognitiva/patología , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Síndrome del Ovario Poliquístico/fisiopatología , Adulto , Encéfalo/metabolismo , Estudios de Casos y Controles , Disfunción Cognitiva/metabolismo , Femenino , Humanos
10.
Abdom Radiol (NY) ; 45(9): 2772-2778, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32705313

RESUMEN

PURPOSE: The imaging features of serous cystadenomas (SCAs) overlap with those of mucinous cystic neoplasms (MCNs) and branch duct intraductal papillary mucinous neoplasms (BD-IPMNs), and an accurate preoperative diagnosis is important for clinical treatment due to their different biological behaviors. The aim of this study was to provide a computed tomographic (CT) feature for the diagnosis of SCAs and estimate whether the "circumvascular sign" can contribute to the discrimination of SCAs from MCNs and BD-IPMNs. METHODS: From August 2011 through December 2019, a total of 71 patients (30 patients with 30 SCAs, 21 patients with 21 MCNs and 20 patients with 22 BP-IPMNs) were enrolled in this study. All patients underwent CT examination and were confirmed by surgical pathology. In addition to patient clinical information, CT features (e.g., location, shape) were evaluated via CT. RESULTS: Central scarring, central calcification and the circumvascular sign were found to be specific CT features for the diagnosis of SCAs and their differential diagnosis from MCNs and BD-IPMNs. All three CT features had high specificity, and both central scarring and central calcification had low sensitivity. When any one of these two features was combined with the circumvascular sign, the sensitivity increased to 83.3%. CONCLUSION: Pancreatic cystic neoplasms that show central scarring, central calcification or the circumvascular sign on CT could be diagnosed as SCAs. When either of the first two features is combined with the circumvascular sign, the diagnostic sensitivity could be increased.


Asunto(s)
Cistoadenoma Mucinoso , Cistadenoma Seroso , Neoplasias Pancreáticas , Cistoadenoma Mucinoso/diagnóstico por imagen , Cistadenoma Seroso/diagnóstico por imagen , Diagnóstico Diferencial , Humanos , Páncreas , Neoplasias Pancreáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X
11.
Carbohydr Polym ; 235: 115977, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32122508

RESUMEN

Exopolysaccharide (R-5-EPS) was isolated from the fermented milk of Lactobacillus helveticus LZ-R-5 and purified by DEAE-52 cellulose anion-exchange column, and characterization of the structure was conducted. Results showed that R-5-EPS was a heteropolysaccharide containing linear repeating units of →6)-ß-D-Galp-(1→3)-ß-D-Glcp-(1→3)-ß-D-Glcp-(1→3)-ß-D-Glcp-(1→3)-ß-D-Glcp-(1→ with an average Mw of 5.41 × 105 Da. Furthermore, at a cellular level, R-5-EPS showed immunostimulatory activity due to its strong effect on increasing proliferation of RAW264.7 macrophages and enhancing phagocytosis, acid phosphatase activity, nitric oxide production and cytokines production in macrophages. These results suggest that R-5-EPS have a potent immunostimulatory activity and may be explored as a potential immunomodulatory agent.


Asunto(s)
Factores Inmunológicos/farmacología , Lactobacillus helveticus/química , Polisacáridos Bacterianos/farmacología , Animales , Conformación de Carbohidratos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Citocinas/análisis , Citocinas/biosíntesis , Factores Inmunológicos/biosíntesis , Factores Inmunológicos/química , Lactobacillus helveticus/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Óxido Nítrico/análisis , Óxido Nítrico/biosíntesis , Tamaño de la Partícula , Fagocitosis/efectos de los fármacos , Polisacáridos Bacterianos/biosíntesis , Polisacáridos Bacterianos/química , Células RAW 264.7 , Propiedades de Superficie
12.
Mikrochim Acta ; 187(1): 36, 2019 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-31820139

RESUMEN

An aptasensor is described for electrochemical determination of organophosphorus pesticides (OPPs), specifically of profenofos, phorate, isocarbophos, and omethoate. The method uses a hairpin aptamer as signalling donor. Its 5' and 3' ends were modified with amino groups and the redox probe ferrocene (Fc), respectively. A nanocomposite consisting of graphene oxide and chitosan (GO-chit) was used to immobilize the aptamer via formation of an amide link. Its good conductivity facilitates monitoring of the electrochemical responses. Upon addition of an OPP, it will be bound by the aptamer. This results in an opening of the hairpin structure. Thus, Fc is shifted away from the surface of the electrode. As a result, the impedance increases and the redox signal of Fc decreases. The electrochemical performance, binding capacity and response of the aptasensor for profenofos, phorate, isocarbophos and omethoate were studied. The limits of detection are as low as 0.01, 0.1, 0.01 and 0.1 nM, respectively. Graphical abstract Schematic representation of an electrochemical aptasensor prepared by immobilizing ferrocene (Fc) labeled hairpin aptamer (HP) on the surface of graphene oxide-chitosan (GO-chit) modified electrode, and its application to the determination of organophosphorus pesticides (OPPs) by voltammetry.


Asunto(s)
Aptámeros de Nucleótidos/química , Técnicas Biosensibles , Técnicas Electroquímicas , Compuestos Organofosforados/análisis , Plaguicidas/análisis , Quitosano/química , Grafito/química , Estructura Molecular , Tamaño de la Partícula , Propiedades de Superficie
13.
Acad Radiol ; 26(10): e292-e297, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30567638

RESUMEN

RATIONALE AND OBJECTIVES: To identify the relationship between enhancement ratio (ER) of aneurysm walls and degrees of inflammation. MATERIALS AND METHODS: Twenty-five white rabbits were used in this study; all underwent surgery to isolate the right common carotid artery (RCCA). Twenty rabbits underwent an aneurysm creation procedure, and 5 underwent a control procedure. In the aneurysm creation procedure, there was surgical exposure of the origin of RCCA and temporary occlusion with an aneurysm clip. The distal RCCA was ligated, and the trapped segment was infused with elastase for 20 minutes, after which the clip was removed. In the control procedure, the trapped segment was infused with saline. High-resolution magnetic resonance imaging was performed at weeks 2, 3, 4, and 5 after the procedure, and wall ER was calculated. After MRI, aneurysms were harvested and stained with hematoxylin-eosin. Pearson correlation analysis and scatter plots were used to evaluate the relationship between wall ER and the degree of inflammation. The relationships between the wall ER, the number of inflammatory cells and time were analyzed by linear graphs. RESULTS: Wall ER positively correlated with inflammatory cell count of the aneurysm wall (r = 0.877, p < 0.001). The relationships between wall ER, the number of inflammatory cells, and time increased and then decreased according linear graphs. CONCLUSION: In this study, the aneurysm wall ER was confirmed to be associated with the degree of inflammation on the rabbit aneurysm model.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Inflamación/complicaciones , Inflamación/diagnóstico por imagen , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Animales , Arteria Carótida Común , Modelos Animales de Enfermedad , Elastasa Pancreática , Proyectos Piloto , Conejos
14.
J Neurointerv Surg ; 10(10): 995-998, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29437934

RESUMEN

OBJECTIVE: Patient related clinical factors and intracranial aneurysms (IAs) at different locations may lead to statistical bias when investigating the rupture risk of IAs. Thus the purpose of this study was to identify the morphological parameters that are related to the rupture of mirror posterior communicating artery aneurysms (PComAAs). METHODS: Between August 2011 and July 2017, 68 patients with mirror PComAAs and aneurysmal subarachnoid hemorrhage were diagnosed by CT angiography at three medical centers. Morphological characteristics for PComAAs included bifurcation, shape, neck width, width, depth, maximum size, flow angle, parent vessel diameter, aspect ratio (AR), depth/width ratio, bottleneck factor, and size ratio (SR). Multiple logistic regression analysis was performed to determine the independent risk factors for rupture. Receiver operating characteristic curve analysis was performed to obtain the optimal thresholds. RESULTS: AR (OR 5.623) and SR (OR 5.570) were more commonly observed in the ruptured cohort. The threshold values of AR and SR were 0.98 and 1.21, respectively. CONCLUSIONS: Mirror PComAAs are a useful model to investigate the rupture risk of PComAAs. AR (≥0.98) and SR (≥1.21) are better predictors of ruptured PComAAs.


Asunto(s)
Aneurisma Roto/diagnóstico por imagen , Aneurisma Intracraneal/diagnóstico por imagen , Hemorragia Subaracnoidea/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Aneurisma Roto/epidemiología , Angiografía Cerebral/métodos , Angiografía por Tomografía Computarizada/métodos , Femenino , Humanos , Aneurisma Intracraneal/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Hemorragia Subaracnoidea/epidemiología
15.
J Neurointerv Surg ; 10(6): 566-570, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28918385

RESUMEN

OBJECTIVES: To evaluate the risk factors for rupture of intracranial aneurysms (IAs) using high resolution MRI (HRMRI). METHODS: 91 consecutive patients with 106 IAs were reviewed from February 2016 to April 2017. Patients and IAs were divided into ruptured and unruptured groups. In addition to the clinical characteristics of the patients, the features of IAs (eg, shape) were evaluated by CT angiography, whereas wall thickness, enhanced patterns, and enhancement ratio (ER) were evaluated by MRI. Multiple logistic regression analysis was used to identify independent risk factors associated with the rupture of IAs. Receiver operating characteristic curve analysis was performed on the final model, and the optimal thresholds were obtained. RESULTS: ER (OR 6.638) and partial wall enhancement (PWE) (OR 6.710) were not markers of aneurysms more prone to rupture, but simply were more commonly found in the ruptured aneurysm cohort. The threshold value for ER was 61.5%. CONCLUSIONS: ER (≥61.5%) and IAs with PWE are better predictors of rupture. Increased attentions should be paid to these factors during assessment of IA rupture.


Asunto(s)
Aneurisma Roto/diagnóstico por imagen , Endotelio Vascular/diagnóstico por imagen , Aneurisma Intracraneal/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Estudios de Cohortes , Angiografía por Tomografía Computarizada/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
16.
Eur Radiol ; 26(11): 4089-4097, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26960542

RESUMEN

OBJECTIVES: Using the human telomerase reverse transcriptase (hTERT) promoter and the modified ferritin heavy chain (Fth) reporter gene, reporter gene expression for MRI was examined in telomerase positive and negative tumour cells and xenografts. METHODS: Activity of the reporter gene expression vector Lenti-hTERT-Fth1-3FLAG-Puro was compared to constitutive CMV-driven expression and to the untransfected parental control in five tumour cell lines: A549, SKOV3, 293T, U2OS and HPDLF. In vitro, transfected cells were evaluated for FLAG-tagged protein expression, iron accumulation and transverse relaxation. In vivo, tumours transduced by lentiviral vector injection were imaged using T2*WI. Changes in tumour signal intensity were validated by histology. RESULTS: Only telomerase positive tumour cells expressed FLAG-tagged Fth and displayed an increase in R2* above the parental control, with a corresponding change in T2*WI. In addition, only telomerase positive tumours, transduced by injection of the reporter gene expression construct, exhibited a change in signal intensity on T2*WI. Tumour histology verified the expression of FLAG-tagged Fth and iron accumulation in telomerase positive tissue. CONCLUSION: Reporter gene expression for MRI, using the Fth reporter and the hTERT promoter, may be a useful strategy for the non-invasive diagnosis of many types of cancer. KEY POINTS: • Modified heavy chain of ferritin can serve as an MR reporter gene • hTERT promoter can direct the expression of reporter gene in cancer cells • MR reporter imaging mediated by hTERT promoter can be used for cancer diagnosis.


Asunto(s)
Apoferritinas/metabolismo , Imagen Molecular/métodos , Neoplasias/diagnóstico , Telomerasa/metabolismo , Análisis de Varianza , Animales , Apoferritinas/genética , Línea Celular Tumoral , Genes Reporteros/genética , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética/métodos , Masculino , Ratones Endogámicos BALB C , Regiones Promotoras Genéticas/genética , Telomerasa/genética , Transfección/métodos
17.
World J Pediatr ; 11(4): 389-91, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24974210

RESUMEN

BACKGROUND: Relapse of acute lymphoblastic leukemia (ALL) in the pancreas is rare. We report a case of a 12-year-old boy who experienced a relapse of ALL in the pancreas after a bone marrow transplant. METHODS: Clinical data, including course of illness, laboratory results, and imaging studies are included. The patient presented with acute pancreatitis, suspected to be secondary to gallstones, with ampullary obstruction. Ultrasound and magnetic resonance imaging demonstrated a distended gallbladder and intra- and extra-hepatic biliary dilatation with a cutoff at the pancreatic head, but with no evidence of gallstones. RESULTS: Ultrasound-guided biopsy of the pancreas revealed ALL in the pancreas. Systematic chemotherapy was recommended, but was declined by the parents. The patient died one week later. CONCLUSION: Relapse of ALL in the pancreas is rare, but when a history of ALL is present, it should be considered in patients with pancreatic enlargement, obstructive jaundice, and pancreatitis.


Asunto(s)
Trasplante de Médula Ósea , Recurrencia Local de Neoplasia/patología , Neoplasias Pancreáticas/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Niño , Diagnóstico por Imagen , Resultado Fatal , Humanos , Biopsia Guiada por Imagen , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia
18.
World J Surg Oncol ; 11: 247, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24083492

RESUMEN

Clear cell tumor of the lung is a rare and benign pulmonary tumor; only sporadic cases have been reported. Here, we report the case of a 38-year-old man with recurrent cough, blood-streaked sputum and left chest pain. A chest computed tomography scan showed a round, homogeneous pulmonary mass in the left lower lobe, which exhibited intense heterogeneous enhancement in the arterial phase and homogeneous in the delay phase after injecting a contrast agent. The patient underwent a fine-needle aspiration biopsy and was diagnosed as having a benign clear cell tumor of the lung. The clinical presentation and radiographic investigation of this tumor are summarized in this paper to recognize this rare disease. Interestingly, we found some differences with previously reported cases.


Asunto(s)
Adenocarcinoma de Células Claras/patología , Neoplasias Pulmonares/patología , Adenocarcinoma de Células Claras/cirugía , Adulto , Biopsia con Aguja Fina , Humanos , Neoplasias Pulmonares/cirugía , Masculino , Pronóstico , Tomografía Computarizada por Rayos X
19.
Zhonghua Gan Zang Bing Za Zhi ; 18(5): 371-3, 2010 May.
Artículo en Chino | MEDLINE | ID: mdl-20510004

RESUMEN

OBJECTIVE: To analyze the CT image characteristics of liver secondary lymphoma. METHODS: The medical records of 13 patients were reviewed. There were 12 non-Hodgkin lymphoma cases and 1 Hodgkin lymphoma case. Abdomen CT scan was performed in all cases, plain scan and enhanced CT scan were performed in 11 cases, plain CT scan was performed in 2 cases. RESULTS: Of the 13 cases, 11 were nodular type, 1 was diffuse type, and 1 was mixed type. Plain CT scan showed low density, enhanced CT showed circular enhancement in 1 case, mild to midrange delayed enhancement in 1 case, midrange enhancement in 1 case, mild enhancement in 2 cases, blood vessel floating sign in 3 cases, no enhancement in 6 cases. CONCLUSIONS: The characteristics of liver secondary lymphoma CT image of liver secondary lymphoma includes blood vessel floating sign and enhancement.


Asunto(s)
Neoplasias Hepáticas/diagnóstico por imagen , Linfoma/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Enfermedad de Hodgkin/diagnóstico por imagen , Humanos , Neoplasias Hepáticas/secundario , Linfoma no Hodgkin/diagnóstico por imagen , Masculino , Persona de Mediana Edad
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