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1.
BMC Med Imaging ; 24(1): 124, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802736

RESUMEN

BACKGROUND: The prevalence of hypertensive heart disease (HHD) is high and there is currently no easy way to detect early HHD. Explore the application of radiomics using cardiac magnetic resonance (CMR) non-enhanced cine sequences in diagnosing HHD and latent cardiac changes caused by hypertension. METHODS: 132 patients who underwent CMR scanning were divided into groups: HHD (42), hypertension with normal cardiac structure and function (HWN) group (46), and normal control (NOR) group (44). Myocardial regions of the end-diastolic (ED) and end-systolic (ES) phases of the CMR short-axis cine sequence images were segmented into regions of interest (ROI). Three feature subsets (ED, ES, and ED combined with ES) were established after radiomic least absolute shrinkage and selection operator feature selection. Nine radiomic models were built using random forest (RF), support vector machine (SVM), and naive Bayes. Model performance was analyzed using receiver operating characteristic curves, and metrics like accuracy, area under the curve (AUC), precision, recall, and specificity. RESULTS: The feature subsets included first-order, shape, and texture features. SVM of ED combined with ES achieved the highest accuracy (0.833), with a macro-average AUC of 0.941. AUCs for HHD, HWN, and NOR identification were 0.967, 0.876, and 0.963, respectively. Precisions were 0.972, 0.740, and 0.826; recalls were 0.833, 0.804, and 0.863, respectively; and specificities were 0.989, 0.863, and 0.909, respectively. CONCLUSIONS: Radiomics technology using CMR non-enhanced cine sequences can detect early cardiac changes due to hypertension. It holds promise for future use in screening for latent cardiac damage in early HHD.


Asunto(s)
Diagnóstico Precoz , Hipertensión , Imagen por Resonancia Cinemagnética , Humanos , Femenino , Masculino , Imagen por Resonancia Cinemagnética/métodos , Persona de Mediana Edad , Hipertensión/diagnóstico por imagen , Hipertensión/complicaciones , Máquina de Vectores de Soporte , Cardiopatías/diagnóstico por imagen , Anciano , Adulto , Teorema de Bayes , Curva ROC , Interpretación de Imagen Asistida por Computador/métodos , Radiómica
2.
J Xray Sci Technol ; 32(3): 569-581, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38217636

RESUMEN

PURPOSE: To compare image quality, iodine intake, and radiation dose in overweight and obese patients undergoing abdominal computed tomography (CT) enhancement using different scanning modes and contrast medium. METHODS: Ninety overweight and obese patients (25 kg/m2≤body mass index (BMI)< 30 kg/m2 and BMI≥30 kg/m2) who underwent abdominal CT-enhanced examinations were randomized into three groups (A, B, and C) of 30 each and scanned using gemstone spectral imaging (GSI) +320 mgI/ml, 100 kVp + 370 mgI/ml, and 120 kVp + 370 mgI/ml, respectively. Reconstruct monochromatic energy images of group A at 50-70 keV (5 keV interval). The iodine intake and radiation dose of each group were recorded and calculated. The CT values, contrast-to-noise ratios (CNRs), and subjective scores of each subgroup image in group A versus images in groups B and C were by using one-way analysis of variance or Kruskal-Wallis H test, and the optimal keV of group A was selected. RESULTS: The dual-phase CT values and CNRs of each part in group A were higher than or similar to those in groups B and C at 50-60 keV, and similar to or lower than those in groups B and C at 65 keV and 70 keV. The subjective scores of the dual-phase images in group A were lower than those of groups B and C at 50 keV and 55 keV, whereas no significant difference was seen at 60-70 keV. Compared to groups B and C, the iodine intake in group A decreased by 12.5% and 13.3%, respectively. The effective doses in groups A and B were 24.7% and 25.8% lower than those in group C, respectively. CONCLUSION: GSI +320 mgI/ml for abdominal CT-enhanced in overweight patients satisfies image quality while reducing iodine intake and radiation dose, and the optimal keV was 60 keV.


Asunto(s)
Medios de Contraste , Obesidad , Sobrepeso , Radiografía Abdominal , Tomografía Computarizada por Rayos X , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/diagnóstico por imagen , Sobrepeso/diagnóstico por imagen , Dosis de Radiación , Intensificación de Imagen Radiográfica/métodos , Radiografía Abdominal/métodos , Tomografía Computarizada por Rayos X/métodos , Anciano de 80 o más Años
3.
J Xray Sci Technol ; 31(6): 1333-1340, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37840466

RESUMEN

OBJECTIVE: To explore the value of applying computed tomography (CT) radiomics based on different CT-enhanced phases to determine the immunotherapeutic efficacy of non-small cell lung cancer (NSCLC). METHODS: 106 patients with NSCLC who underwent immunotherapy are randomly divided into training (74) and validation (32) groups. CT-enhanced arterial and venous phase images of patients before treatment are collected. Region-of-interest (ROI) is segmented on the CT-enhanced images, and the radiomic features are extracted. One-way analysis of variance and least absolute shrinkage and selection operator (LASSO) are used to screen the optimal radiomics features and analyze the association between radiomics features and immunotherapy efficacy. The area under receiver-operated characteristic curves (AUC) along with the sensitivity and specificity are computed to evaluate diagnostic effectiveness. RESULTS: LASSO regression analysis screens and selects 6 and 8 optimal features in the arterial and venous phases images, respectively. Applying to the training group, AUCs based on CT-enhanced arterial and venous phase images are 0.867 (95% CI:0.82-0.94) and 0.880 (95% CI:0.86-0.91) with the sensitivities of 73.91% and 76.19%, and specificities of 66.67% and 72.19%, respectively, while in validation group, AUCs of the arterial and venous phase images are 0.732 (95% CI:0.71-0.78) and 0.832 (95% CI:0.78-0.91) with sensitivities of 75.00% and 76.00%, and specificities of 73.07% and 75.00%, respectively. There are no significant differences between AUC values computed from arterial phases and venous phases images in both training and validation groups (P < 0.05). CONCLUSION: The optimally selected radiomics features computed from CT-enhanced different-phase images can provide new imaging marks to evaluate efficacy of the targeted therapy in NSCLC with a high diagnostic value.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/terapia , Tomografía Computarizada por Rayos X , Inmunoterapia , Área Bajo la Curva , Estudios Retrospectivos
4.
Jpn J Radiol ; 41(6): 669-679, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36607550

RESUMEN

PURPOSE: To conduct a comparative study of image quality, radiation dose, and iodine intake in hepatic computed tomographic angiography (CTA) of overweight patients with different Gemstone Spectral Imaging (GSI) noise indexes combined with different concentrations of contrast medium. MATERIALS AND METHODS: Ninety patients with a body mass index of ≥ 25 kg/m2 were divided into three groups (A, B and C), each with 30 patients. The three groups underwent hepatic CTA with different NI of 7, 11 and 15, respectively, and were injected with different iodine concentrations of 370, 350 and 320 mgI/mL, respectively. Five sets of images at 40-60 keV (interval, 5 keV) were reconstructed in each group. The CT value, image noise, contrast-to-noise ratio (CNR) and subjective score of the hepatic artery and vein, and portal vein in different monochromatic image sets were analyzed to select the optimal energy level in each group. The differences in CT value, image noise, CNR and a subjective score of hepatic artery and vein, portal vein in the optimal monochromatic images among the three groups were compared, the volume CT dose index (CTDIvol) and dose-length product (DLP) were recorded, and the effective dose and iodine intake were calculated. RESULTS: The 40 keV was determined to be the optimal energy level for the monochromatic image sets in each group. No significant group differences were noted in the CT value, image noise, CNR, and subjective image scores of the hepatic artery and vein, and portal vein for the optimal monochromatic images (P > 0.05). Compared with group A, the effective dose and iodine intake in group B were reduced by 50.18% and 9.3%, and by 58.12% and 14.23% in group C, respectively. CONCLUSION: A low-concentration contrast medium combined with a high-noise GSI index in hepatic CTA of overweight patients can reduce the radiation dose and iodine intake while ensuring image quality.


Asunto(s)
Angiografía por Tomografía Computarizada , Yodo , Humanos , Angiografía por Tomografía Computarizada/métodos , Estudios de Factibilidad , Sobrepeso/diagnóstico por imagen , Dosis de Radiación , Medios de Contraste , Interpretación de Imagen Radiográfica Asistida por Computador/métodos
5.
J Xray Sci Technol ; 30(6): 1261-1272, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36214032

RESUMEN

OBJECTIVES: To compare image quality, radiation dose, and iodine intake of coronary computed tomography angiography (CCTA) acquired by wide-detector using different tube voltages and different concentrations of contrast medium (CM) for overweight patients. MATERIALS AND METHODS: A total of 150 overweight patients (body mass index≥25 kg/m2) who underwent CCTA are enrolled and divided into three groups according to scan protocols namely, group A (120 kVp, 370 mgI/ml CM); group B (100 kVp, 350 mgI/ml CM); and group C (80 kVp, 320 mgI/ml CM). The CT values, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and figure-of-merit (FOM) of all images are calculated. Images are subjectively assessed using a 5-point scale. In addition, the CT dose index volume (CTDIvol) and dose length product (DLP) of each patient are recorded. The effective radiation dose (ED) is also calculated. Above data are then statistically analyzed. RESULTS: The mean CT values, SNR, CNR, and subjective image quality of group A are significantly lower than those of groups B and C (P < 0.001), but there is no significant difference between groups B and C (P > 0.05). FOMs show a significantly increase trend from group A to C (P < 0.001). The ED values and total iodine intake in groups B and C are 30.34% and 68.53% and 10.22% and 16.85% lower than those in group A, respectively (P < 0.001). CONCLUSION: The lower tube voltage and lower concentration of CM based on wide-detector allows for significant reduction in iodine load and radiation dose in CCTA for overweight patients comparing to routine scan protocols. It also enhances signal intensity of CCTA and maintains image quality.


Asunto(s)
Angiografía por Tomografía Computarizada , Yodo , Humanos , Angiografía por Tomografía Computarizada/métodos , Sobrepeso/diagnóstico por imagen , Dosis de Radiación , Estudios de Factibilidad , Medios de Contraste , Estudios Prospectivos , Angiografía Coronaria/métodos , Tomografía Computarizada por Rayos X/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos
6.
Dalton Trans ; 50(37): 12814-12820, 2021 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-34494040

RESUMEN

A dinuclear dysprosium cluster [Dy2(NO3)4(H2O)2(L)2]·2CH3CN was successfully prepared by employing HL (HL = 2,6-dimethoxyphenol) and Dy(NO3)3·6H2O in a mixture of CH3OH and CH3CN. The conversion of this Dy2 compound by reaction with additional deprotonated ligand generated a Dy9 cluster [Dy9(µ4-OH)2(µ3-OH)8(µ2-OCH3)4(NO3)8(H2O)8(L)4](OH)·2H2O with the well-known "diabolo" topology. Magnetic investigation revealed that both of the clusters exhibit typical SMM characteristics, and variable magnetic relaxation with the energy barrier changing from 217.87 K to 9.24 K along with the transition from a dinuclear dysprosium cluster to a nonanuclear one. Ab initio calculations further confirm the corresponding structure-activity relationships that originate the different magnetic behaviours. This design may afford a feasible strategy for modulating the magnetic relaxation dynamics of polynuclear systems.

7.
Chem Commun (Camb) ; 55(46): 6527-6530, 2019 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-31099808

RESUMEN

Three metal-organic frameworks have been synthesized by using N-containing ligands and meso-tetra(4-carboxyphenyl)porphyrin, which all exhibit distinct selective adsorption capacities toward various organic dyes, illustrating the most important influence of the structural tuning.

8.
Cell Physiol Biochem ; 47(1): 97-106, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29763886

RESUMEN

BACKGROUND/AIMS: Unlike other organs, which only have one set of capillary network, the renal microvasculature consists of two sets of capillary network series connected by efferent arterioles. Angiotensin II constricts the efferent glomerular artery. Hence, renal tumor blood flow (BF) distribution may be different from tumors in other organs. This study aims to investigate the effects of angiotensin II on the hemodynamics of intrarenal VX2 tumors using perfusion computed tomography(CT). METHODS: Twenty-four male New Zealand white rabbits were randomly divided into three groups: groups A (blank controls), group B (negative controls), and group C (angiotensin II-treated animals). Group B and C were established to the model of intrarenal VX2 tumors. Furthermore, perfusion CT of the kidney was performed in each group. Prior to perfusion CT scan in group C, the mean arterial blood was elevated to 150-160 mmHg by angiotensin II. The BF, blood volume (BV), mean transit time (MTT), capillary permeability-surface area product (PS), and relative permeability-surface area product (RPS) of tumors and renal tissues were calculated. RESULTS: Compared with normal renal cortex tissues in group A, the BF, BV and PS values of tumors in group B were significantly lower, MTT was prolonged and RPS increased. Compared with group B, only the RPS of these tumors increased from 83.23 ± 29.17% to 120.94 ± 31.84% by angiotensin II infusion. Angiotensin II significantly increased the RPS value of the renal cortex distant from the tumor (CDT) and the right renal cortex (RRC). CONCLUSIONS: Perfusion CT can accurately observe the influence of angiotensin II on normal and tumor BF in kidneys. This clarifies the effect of angiotensin II on intrarenal tumor hemodynamics.


Asunto(s)
Angiotensina II/farmacología , Hemodinámica/efectos de los fármacos , Neoplasias Renales/irrigación sanguínea , Riñón/irrigación sanguínea , Tomografía Computarizada por Rayos X/métodos , Vasoconstrictores/farmacología , Animales , Riñón/diagnóstico por imagen , Riñón/efectos de los fármacos , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/tratamiento farmacológico , Masculino , Neovascularización Patológica/diagnóstico por imagen , Neovascularización Patológica/tratamiento farmacológico , Perfusión/métodos , Conejos
9.
Yi Chuan ; 39(7): 568-575, 2017 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-28757471

RESUMEN

How the organ size is determined is a fundamental question in developmental biology. The metazoan Hippo signaling pathway is well established to negatively regulate organ sizes. Recent studies in plants have started to shape an emerging Hippo signaling pathway. In this review, we summarize the studies in the past decade on the two known components of plant Hippo signaling pathway, the Ste20/Hippo homolog SIK1, and the MOB1/Mats homolog MOB1, with a focus on their developmental functions. Then we envision future discoveries that may shape a complete Hippo signaling pathway in plants.


Asunto(s)
Proteínas de Plantas/fisiología , Proteínas Serina-Treonina Quinasas/fisiología , Transducción de Señal/fisiología , Tamaño de los Órganos
10.
BMC Complement Altern Med ; 16: 68, 2016 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-26895969

RESUMEN

BACKGROUND: To appraise critically whether published trials of ShenXiong glucose injection for patients with acute ischemic stroke (AIS) are of sufficient quality, and in addition to rate the quality of evidence by using the GRADE approach (grading of recommendations, assessment, development, and evaluation, GRADE). METHODS: A literature search was performed in the Cochrane Library, MEDLINE, EMBASE, CBM, Chinese TCM (traditional Chinese medicine) Database, CNKI, VIP, WanFang Databases until January 2015. The limits were patients with AIS and randomized controlled trials (RCTs) or quasi-RCTs. Studies by which patients suffering intracerebral haemorrhage were excluded. RESULTS: Twelve studies fulfilled the inclusion criteria. We found significant benefits of ShenXiong glucose injection compared with conventional treatment in improving activities of daily living function at 4 weeks (MD = 34.12, 95 % CI: 29.07, 39.17), neurological function deficit at 2 weeks (MD = -5.39, 95% CI: -6.90, -3.87), 4 weeks (MD = -5.16, 95 % CI: -6.49, -3.83), and clinical effects at 4 weeks (RR = 1.17, 95% CI: 1.10, 1.24). No trials reported the effects of ShenXiong glucose injection on the risk of early, deterioration, or quality of life. No adverse events were reported within the whole follow-up period. CONCLUSIONS: The use of ShenXiong glucose injection may improve rehabilitation for patients with acute ischemic stroke, however, as the GRADE approach indicated low to moderate quality of available evidence as well as insufficient information about harm and patients preference, the recommendations were not provided for ShenXiong glucose injection taking as a therapeutic intervention to patients with acute ischemic stroke.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Humanos
11.
Inorg Chem ; 54(7): 3331-6, 2015 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-25760643

RESUMEN

A new three-dimensional magnetic network, [Co9(OH)6(C42H24O18P3N3)2(H2O)8] (1), has been successfully prepared by utilizing the flexible hexacarboxylate ligand derived from cyclotriphosphazene, which had been characterized by single-crystal X-ray diffraction and magnetic measurement. This compound consists of one-dimensional (1D) cobalt-hydroxyl chains based on planar nonanuclear clusters, which are located in the b-c plane to form the nearly two-dimensional cobalt layer. Magnetic measurements reveal that 1 shows spin-canted antiferromagnetism with spin-glass behavior. These results suggest that reasonable design and choice of large carboxylate ligand based on a specific scaffold could be effective for the construction of magnetic materials based on a novel 1D magnetic chain.

12.
Ying Yong Sheng Tai Xue Bao ; 26(10): 3011-9, 2015 Oct.
Artículo en Chino | MEDLINE | ID: mdl-26995908

RESUMEN

Pot experiments were carried out to explore the approach of optimizing crop group performance through restriction of individual growth redundancy and increasing crop yield potential. Two winter wheat varieties of 'Xiaoyan-22' (with moderate tillering ability) and 'Zhengmai-7698' (with strong tillering ability) were chosen to investigate the effects of two irrigation schedules (full irrigation and regulated deficit irrigation) and three kinds of tillering interference (only retaining the main stem and the biggest tiller at jointing stage; removing all nonbearing tillers at heading stage; and without any interference as the control treatment). Thus, we simulated the compensation effects of different water supplies and unpredictable disturbances on the physiology, growth, yield, and water use efficiency of winter wheat. The results showed that there existed growth redundancy for both varieties. Compared with 'Xiaoyan-22', 'Zhengmai-7698' had relatively higher tillering number but weak panicle traits. Regulated deficit irrigation and removing all nonbearing tillers at heading stage could reduce growth redundancy, weaken competitive ability, change source-sink relations, and optimize resources allocation. However, excessive elimination of redundancy (e.g. only retaining the main stem and the biggest tiller at jointing stage) could destroy the inherent root-shoot balance and functional structure of plant and lead to inadequate compensation. In contrast to the control treatment (full irrigation and without any disturbance), the combination of regulated deficit irrigation and removing all nonbearing tillers at heading stage could help crops sufficiently exploit and utilize their own regulation potentials at spatial and temporal scales and finally realize compensation growth. The combination above could increase the water use efficiency by 20.4% - 25.4% without remarkable impact on grain yield, and hence, could be suitable for wheat growth redundancy reduction.


Asunto(s)
Riego Agrícola , Triticum/crecimiento & desarrollo , Agua/fisiología , Grano Comestible , Tallos de la Planta/fisiología , Triticum/fisiología
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