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1.
Sci Total Environ ; 920: 170558, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38325459

RESUMO

The trees of the Dongzhai Harbor mangrove forest suffer from antibiotic contamination from surrounding aquaculture areas. Despite this being one of the largest mangrove forests in China, few studies have focused on the antibiotic pollution status in these aquaculture areas. In the present study, the occurrence, distribution, and risk assessment of 37 antibiotics in surface water and sediment samples from aquaculture areas around Dongzhai Harbor mangrove forests were analyzed. The concentration of total antibiotics (∑antibiotics) ranged from 78.4 ng/L to 225.6 ng/L in surface water (except S14-A2) and from 19.5 ng/g dry weight (dw) to 229 ng/g dw in sediment. In the sediment, the concentrations of ∑antibiotics were relatively low (19.5-52.3 ng/g dw) at 75 % of the sampling sites, while they were high (95.7-229.0 ng/g dw) at a few sampling sites (S13-A1, S13D, S8D). The correlation analysis results showed that the Kd values of the 9 antibiotics were significantly positively correlated with molecular weight (MW), Kow, and LogKow. Risk assessment revealed that sulfamethoxazole (SMX) in surface water and SMX, enoxacin (ENX), ciprofloxacin (CFX), enrofloxacin (EFX), ofloxacin (OFX), and norfloxacin (NFX) in sediment had medium/high risk quotients (RQs) at 62.5 % and 25-100 %, respectively, of the sampling sites. The antibiotic mixture in surface water (0.06-3.36) and sediment (0.43-309) posed a high risk at 37.5 % and 66.7 %, respectively, of the sampling sites. SMX was selected as an indicator of antibiotic pollution in surface water to assist regulatory authorities in monitoring and managing antibiotic pollution in the aquaculture zone of Dongzhai Harbor. Overall, the results of the present study provide a comprehensive and detailed analysis of the characteristics of antibiotics in the aquaculture environment around the Dongzhai Harbor mangrove system and provide a theoretical basis for the source control of antibiotics in mangrove systems.


Assuntos
Antibacterianos , Poluentes Químicos da Água , Antibacterianos/análise , Áreas Alagadas , Aquicultura , Sulfametoxazol/análise , Água/análise , Medição de Risco , China , Poluentes Químicos da Água/análise , Monitoramento Ambiental
2.
Indian J Ophthalmol ; 70(5): 1736-1741, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35502063

RESUMO

Purpose: To evaluate changes in the levator palpebrae superioris (LPS) muscle on 3.0 T magnetic resonance imaging (MRI) after triamcinolone acetonide injection for treating upper lid retraction (ULR) with Graves' ophthalmopathy (GO) and to explore the value of LPS muscle quantitative measurement for clinical treatment. Methods: Patients with GO showing ULR were studied retrospectively and they underwent 3.0 T MRI scans before and after subconjunctival injection o f triamcinolone acetonide. The largest thickness (T) and highest signal intensity (SI) of LPS muscle on the affected eyes were measured in the sequences of coronal T2-weighted, fat-suppressed fast spin echo imaging (T2WI-fs) and T1-weighted, fat-suppressed, contrast-enhanced fast spin echo imaging (T1WI-fs + C), respectively. The SI ratio (SIR) (LPS muscle SI/ipsilateral temporalis SI) was calculated individually. Depending on the therapeutic effect, patients were divided into effective group and non-effective group. Independent t-test was used to compare SIR and T of LPS muscle in different treatment groups before treatment, and paired sample t-test was used to compare SIR and T of LPS muscle before and after treatment. Then cut-off level for predicting therapeutic effect and the receiver operating characteristic curve (ROC) curve were analyzed. Results: Sixty-two patients (77 eyes) were enrolled. After treatment, the T of LPS muscle showed significant decrease in all sequences in both effective and non-effective treatment groups. However, changes in SIR of LPS muscle in the two groups were different; SIR of LPS muscle on T2WI-fs and T1WI-fs + C decreased after treatment in the effective group (PT2 < 0.001, PT1 + C < 0.001) and SIR of LPS muscle showed no statistically difference in all sequences (all P > 0.05) in the non-effective group. There was a correlation between SIR of LPS muscle before treatment and after treatment with triamcinolone acetonide injection, which was that SIR of LPS muscle in the effective treatment group was lower than that in the non-effective treatment group on T1WI-fs + C (P < 0.001). SIR of LPS muscle on T1WI-fs + C showed 87.5% sensitivity and 66.7% specificity to predict therapeutic effect (area under the ROC curve [AUC] = 0.840). Conclusion: In GO patients with ULR, 3.0 T MRI can be used to evaluate the response of triamcinolone acetonide injection. SIR of LPS may be a predictor of its efficacy.


Assuntos
Doenças Palpebrais , Triancinolona Acetonida , Túnica Conjuntiva , Doenças Palpebrais/tratamento farmacológico , Humanos , Lipopolissacarídeos/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Transtornos da Visão
3.
Magn Reson Imaging ; 78: 18-24, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33556484

RESUMO

BACKGROUND: To evaluate 3-dimensional amide proton transfer weighted (APTw) imaging for type I endometrial carcinoma (EC), and investigate correlations of Ki-67 labelling index with APTw and intravoxel incoherent motion (IVIM) imaging. METHODS: 54 consecutive patients suspected of endometrial lesions underwent pelvic APTw and IVIM imaging on a 3 T MR scanner. APTw values and IVIM-derived parameters (Dt, D*, f) were independently measured by two radiologists on 22 postoperative pathological confirmed of type I EC lesions. Results were compared between histological grades and Ki-67 proliferation groups. ROC analysis was performed. Pearson's correlation analysis was performed for APTw values and IVIM-derived parameters with Ki-67 labeling index. RESULTS: APTw values and Dt, D*, f of all type I EC were 2.9 ± 0.1%, 0.677 ± 0.027 × 10-3 mm2/s, 31.801 ± 11.492 × 10-3 mm2/s, 0.179 ± 0.050 with inter-observer ICC 0.996, 0.850, 0.956, 0.995, respectively. APTw values of Ki-67 low-proliferation group (<30%, n = 8) were 2.5 ± 0.2%, significantly lower than the high-proliferation group (>30%, n = 14) with APTw values of 3.1 ± 0.1% (p = 0.016). Area under the curve was 0.768. APTw values of type I EC were moderately positively correlated with Ki-67 labelling index (r = 0.583, p = 0.004). There was no significant difference of Dt (p = 0.843), D* (p = 0.262), f (p = 0.553) between the two groups. No correlation was found between IVIM-derived parameters and Ki-67 labelling index (Dt, p = 0.717; D* p = 0.151; f, p = 0.153). CONCLUSION: 3D TSE APTw imaging is a feasible approach for detecting type I EC. Ki-67 labeling index positively moderately correlates with APTw not with IVIM.


Assuntos
Amidas/química , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/patologia , Imageamento Tridimensional/métodos , Antígeno Ki-67/metabolismo , Prótons , Adulto , Idoso , Proliferação de Células , Neoplasias do Endométrio/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC
4.
Mol Imaging Biol ; 23(3): 446-455, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33185840

RESUMO

PURPOSE: To evaluate the utility of three-dimensional (3D) amide proton transfer-weighted (APTw) imaging for differentiation of endometrial adenocarcinoma and uterine benign lesions. PROCEDURES: This prospective study enrolled 22 normal volunteers and 113 patients with suspicious uterine lesions, including endometrial adenocarcinoma, leiomyoma, and adenomyosis. Pelvic APTw MRI was performed on a 3-T MRI scanner with default APTw parameters. Two radiologists blindly evaluated uterine lesion APTw image quality by a 3-point Likert scale and independently measured APTw values on images with excellent to good image quality. Inter-reader agreement was evaluated. The Mann-Whitney U test with Bonferroni correction was used to compare the differences among different types of uterine lesions. A receiver operating characteristic analysis was performed. RESULTS: A total of 111 lesions (33 endometrial adenocarcinoma, 26 leiomyoma, and 52 adenomyosis lesions) from 99 patients revealing a majority of good quality with excellent inter-reader agreement were included for the image quality evaluation. APTw values of endometrial adenocarcinoma were 2.9 ± 0.1 %, significantly higher than those of leiomyoma (1.9 ± 0.1 %), adenomyosis (2.2 ± 0.1 %), and normal uterine myometrium (1.9 ± 0.1 %) (all p < 0.0001). The area under the receiver operating characteristic curve for differentiating endometrial adenocarcinoma from leiomyoma, adenomyosis, and myometrium was 0.87, 0.85, and 0.91, respectively. Feasible threshold APTw values of each group were determined as 2.4 %, 2.7 %, and 2.4 % with a sensitivity of 83.3 %, 76.7 %, and 83.3 % and a specificity of 83.3 %, 81.6 %, and 86.4 %, respectively. CONCLUSIONS: Malignant endometrial adenocarcinoma had significantly higher APTw values than leiomyoma, adenomyosis, and normal uterine myometrium. Our study adds to the growing body of validation on 3D APTw imaging and uterine lesions.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias do Endométrio/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neoplasias Uterinas/diagnóstico por imagem , Adenomiose/diagnóstico por imagem , Adulto , Idoso , Amidas , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Leiomioma/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Prospectivos , Prótons , Curva ROC
5.
Eur J Radiol ; 124: 108779, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31935594

RESUMO

PURPOSE: We sought to evaluate the image quality and compare the signal intensity (SI) and apparent diffusion coefficient (ADC) maps of ultra-high b-value (2000 s/mm2; B2) images against those of 800 s/mm2 b-value (B1) images of diffusion-weighted imaging (DWI) for cervical cancer. METHOD: This study was approved by the institutional review board. Sixty patients diagnosed with cervical cancer by pathology were prospectively included. Female pelvic magnetic resonance imaging was performed using a 3 T magnetic resonance scanner; B1 and B2 images were obtained for evaluation. Two radiologists blinded to the scan parameters evaluated the images for signal loss in the background, spatial distortion, image ghosting, confidence in the lesion delineation, and overall image quality using a 5-point scoring system. The scores were compared using a paired Wilcoxon test. SI was measured in the B1 and B2 images for the tumour and normal reference tissues. Additionally, the SI contrast ratios were calculated and compared using the Mann-Whitney U test, the ADC values of tumours and normal tissues were measured, and the maximum tumour diameters were measured from the B1 and B2 images and compared with those from the T2-weighted images, which was the reference standard. RESULTS: The signal loss in the background, confidence of the lesion delineation and overall image quality scores were higher for the B2 images than for the B1 images (all p < 0.001). The contrast ratios of the tumour-to-normal SI were also higher for the B2 images than for the B1 images (p < 0.01). The mean ADC values derived from the B2 images showed better correlations with the tumour differentiation grades than those from the B1 images. The tumour diameters measured from the B2 images experienced less bias than those from the B1 images. CONCLUSIONS: B2 images of DWI are technically feasible to acquire and provide more promising additional information for the delineation of cervical cancer tumours than B1 images of the female pelvis.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Idoso , Algoritmos , Colo do Útero/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Adulto Jovem
6.
J Magn Reson Imaging ; 50(4): 1318-1325, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30859696

RESUMO

BACKGROUND: Amide proton transfer-weighted (APTw) imaging has shown great potential in the diagnosis of cancer, but has yet not been well studied in cervical cancer. PURPOSE: To evaluate the image quality and clinical feasibility of APTw MRI for cervical cancer. STUDY TYPE: Prospective. POPULATION: In all, 75 patients with cervical lesions and 49 healthy volunteers. FIELD STRENGTH/SEQUENCE: 3.0 T, 3D turbo spin echo (TSE) APTw sequence. ASSESSMENT: Three radiologists, blinded to the clinical data, independently evaluated APTw image quality with a 5-point Likert scale on 64 patients with pathologically confirmed cervical cancer. APT values, calculated based on asymmetry of acquired Z-spectrum with respect to water frequency, using 3D turbo spin echo volume acquisition with B0 correction, were independently measured by two radiologists, twice for each observer, on 52 cervical cancer lesions and 49 normal cervical stroma with a mean region of interest area of 638.6 mm2 and 557.5 mm2 , respectively. STATISTICAL TESTS: Interobserver agreement was evaluated by Kendall's W test. Intra- and interobserver interclass correlation coefficients (ICC) were computed. Student's t-test was used to compare the differences of APT values between cervical cancer and normal cervix; receiver operating characteristic analysis was performed. RESULTS: Most cases revealed good APTw image quality with excellent agreement (Kendall's W = 0.850, P < 0.001). APT values of cervical cancer and normal cervical stroma were 2.745 ± 0.065 and 1.853 ± 0.059, respectively, with a significant difference (P < 0.0001). Intraobserver ICCs were 0.963 and 0.960 for two readers. Interobserver ICC was 0.993. Area under the curve (AUC) for differentiating cervical cancer from normal cervical stroma was 0.927. The feasible threshold value for AUC was determined as 2.221 with sensitivity of 84.62% and specificity of 83.66%. DATA CONCLUSION: 3D TSE APTw MRI is feasible in cervical cancer. Cervical cancer showed significantly higher APT values than normal cervix. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1318-1325.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Idoso , Amidas , Colo do Útero/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Prótons , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
7.
Ann Transl Med ; 5(16): 319, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28861416

RESUMO

BACKGROUND: Using high-resolution magnetic resonance imaging (HRMRI), we sought to investigate the underlying etiology of intracranial stenosis in young patients. METHODS: We retrospectively studied 122 Chinese young adult patients (from 18 to 45 years old, mean age 36.2±7.5 years) with unilateral middle cerebral artery (MCA) stenosis based on a prospectively established HRMRI database. The eccentricity, degree of stenosis, and remodeling types of MCA lesions were analyzed. The MCA lesions were classified as eccentric (presumed atherosclerosis) or concentric stenosis (presumed non-atherosclerosis). The clinical data and vessel wall properties were compared between the patients >35 years old and the patients ≤35 years old. RESULTS: Eccentric stenosis was observed in 98 (80.3%) patients and concentric stenosis in 24 (19.7%) patients. The patients with eccentric stenosis were older (37.5±6.8 vs. 31.4±8.4 years old, P<0.001) and more likely had atherosclerosis risk factors (56.1% vs. 25.0%, P=0.006). The patients >35 years old had higher prevalence (90.1% vs. 66.7%, P=0.001) of eccentric stenosis and atherosclerosis factors (60.6% vs. 35.3%, P=0.006) than the patients ≤35 years old. Most of the patients with concentric stenosis were ≤35 years old (17/24, 70.8%) and were female (16/24, 66.7%). Binary Logistic analysis suggested smoking (OR =3.171; 95% CI, 1.210-8.314) and remodeling ratio (OR =1.625; 95% CI, 1.001-2.636) were independent predictive factors for symptomatic stenosis. CONCLUSIONS: Atherosclerosis is the most common cause of intracranial stenosis in Chinese young patients. Non-atherosclerosis disease is an important etiology in young female, especially in the patients aged 35 years old or younger.

8.
Light Sci Appl ; 6(4): e16251, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30167243

RESUMO

The ability to measure the orbital angular momentum (OAM) distribution of vortex light is essential for OAM applications. Although there have been many studies on the measurement of OAM modes, it is difficult to quantitatively and instantaneously measure the power distribution among different OAM modes, let alone measure the phase distribution among them. In this work, we propose an OAM complex spectrum analyzer that enables simultaneous measurements of the power and phase distributions of OAM modes by employing the rotational Doppler effect. The original OAM mode distribution is mapped to an electrical spectrum of beat signals using a photodetector. The power and phase distributions of superimposed OAM beams are successfully retrieved by analyzing the electrical spectrum. We also extend the measurement technique to other spatial modes, such as linear polarization modes. These results represent a new landmark in spatial mode analysis and show great potential for applications in OAM-based systems and optical communication systems with mode-division multiplexing.

9.
Neurology ; 86(21): 1957-63, 2016 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-27164677

RESUMO

OBJECTIVE: In this study, we sought to examine the prevalence and clinical relevance of deep tiny flow voids (DTFV) in patients with steno-occlusive middle cerebral artery (MCA) disease on high-resolution MRI (HRMRI). METHODS: We retrospectively reviewed the HRMRI and clinical data of 477 patients with MCA steno-occlusive disease. The presence and distribution of DTFV, defined as 3 or more flow voids along the affected MCA on at least 2 consecutive T2-weighted image slices on HRMRI, were observed. The relationships among DTFV, the degree of stenosis (mild <50%, moderate 50%-70%, severe 70%-99%, and occlusion), and infarctions were analyzed. To clarify the difference between DTFV and moyamoya collaterals, we compared the HRMRI findings of the patients with DTFV and 102 patients with moyamoya disease. RESULTS: The prevalence of DTFV was 1.4% in mild stenosis, 12.8% in moderate stenosis, 40.6% in severe stenosis, and 50.7% in MCA occlusions. Of the 112 patients with DTFV, 57 (50.9%) had all 4 quadrants (superior, inferior, dorsal, and ventral sides) of the MCA involved. DTFV were more common in asymptomatic patients than in symptomatic patients with severe stenosis (49.3% vs 30.9%, p = 0.025) and occlusions (68.0% vs 41.7%, p = 0.033). Obvious flow voids in the basal ganglia region were observed in 58 patients (56.9%) with moyamoya disease but in none of the patients with DTFV (p < 0.001). CONCLUSIONS: DTFV are common in patients with severe steno-occlusive MCA disease, especially in asymptomatic patients. We hypothesize that DTFV originate from new vessel network formation in response to chronic cerebral ischemia.


Assuntos
Infarto da Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/diagnóstico por imagem , Angiografia Cerebral , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/epidemiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Infarto da Artéria Cerebral Média/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/epidemiologia , Variações Dependentes do Observador , Prevalência , Estudos Prospectivos , Estudos Retrospectivos
10.
Eur J Radiol ; 85(4): 803-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26971427

RESUMO

PURPOSE: To evaluate the feasibility of high-resolution 3D CUBE T1WI for intracranial vessel wall imaging. METHODS: High-resolution 3D CUBE T1 weighted intracranial vessel wall images (0.4 mm × 0.4 mm × 0.4 mm) of 50 patients were retrospectively evaluated. A 5-point scale (1 poor, 5 excellent) was used to score the imaging quality for displaying the vessel wall of every intracranial artery segments. The inter-observer and intra-observer reproducibility of identifying plaques, intraplaque hemorrhage/luminal thrombosis, and wall enhancement were calculated. RESULTS: Totally 893 artery segments were evaluated. 3D CUBE T1WI displayed the arteries wall and lumen clearly, with the highest score (4.920 ± 0.837) for the C6-7 segments and the lowest (3.370 ± 1.107) for the C3 segments of the internal carotid artery (ICA). Both intra-observer and inter-observer reproducibility were high for identification of normal walls (κ=0.928, 95% confidence interval [CI] 0.891-0.954; κ=0.911, CI 0.868-0.940), plaque (κ=0.924, CI 0.884-0.954; κ=0.907, CI 0.866-0.943), luminal thrombosis (κ=1.000, CI 1.000-1.000; κ=1.000, CI 1.000-1.000), and wall enhancement (κ=1.000, CI 1.000-1.000; κ=0.914, CI 0.863-0.961). CONCLUSIONS: High-resolution 3D CUBE T1WI displayed intracranial wall and lumen clearly, and detected intracranial artery abnormalities with high reproducibility.


Assuntos
Angiografia Cerebral/métodos , Imageamento Tridimensional/métodos , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Artéria Basilar/patologia , Artéria Carótida Interna/patologia , Estenose das Carótidas/diagnóstico , Angiografia Cerebral/estatística & dados numéricos , Meios de Contraste , Estudos de Viabilidade , Feminino , Gadolínio DTPA , Humanos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Imageamento Tridimensional/estatística & dados numéricos , Doenças Arteriais Intracranianas/diagnóstico , Trombose Intracraniana/diagnóstico , Angiografia por Ressonância Magnética/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodos , Neuroimagem/estatística & dados numéricos , Placa Aterosclerótica/diagnóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Artéria Vertebral/patologia
11.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 37(5): 567-74, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26564509

RESUMO

OBJECTIVE: To evaluate the feasibility of three-dimensional pseudo-continuous arterial spin label (3D pCASL) non-contrast enhanced perfusion imaging applied to head and neck tumors in high-field MR and detect the effects of different postlabeling delay (PLD) time on image quality and the reliability of repeated measurements of tumor blood flow (BF) in different 3D pCASL groups. METHODS: In this prospective study,all the 25 patients received neck 3D pCASL non-contrast enhanced perfusion examinations in a 3.0 T MR system by using an 8-channel head and neck joint coil. Conventional T1-weighted (TIWI) and T2-weighted imaging (T2WI) were performed firstly. Finally,three 3D pCASL with different PLD time [ASL1(PLD1=1525 ms),ASL2 (PLD2=2025 ms), ASL3(PLD3=2525 ms)] were acquired. Patients' perfusion-weighted images acquired from different 3D pCASL sequences underwent the analysis of signal to noise ratio (SNR) and contrast noise ratio (CNR) for tumors. Two observers performed the qualitative assessments on spiral artifacts and vascular artifacts of perfusion-weighted images from different 3D pCASL sequences. Blood flow (BF) of tumors from different 3D pCASL sequences were measured by the two observers respectively for the first time and by observer 2 for the second time. RESULTS: Seventeen enrolled patients (age:50.1 ± 12.7 years,M/F=10:7) with histopathologic. RESULTS: underwent the evaluation of image quality and measurements of BF values. The SNRs and CNRs of ASL1,ASL2, and ASL3 showed a descending trendency. SNRs (P=0.011) and CNRs (P=0.009) of ASL1 were significant higher than those of ASL3. There was no significant difference of scores of spiral artifacts among the three ASL groups (P=0.932). The scores of vascular artifacts of ASL1,ASL2,and ASL3 showed a descending trendency,also. And scores of ASL1 was significant higher than that of ASL3(P=0.000). The intraclass correlation coefficient (ICC) of intre-and intraobserver were high (ICC>0.9). Although the BF values of ASL1,ASL2, and ASL3 showed an ascending trendency,there was no significant difference among the three groups (P=0.977). CONCLUSIONS: The 3D pCASL no-contrast enhanced perfusion MR imaging can be used for head and neck tumor. The image quality of perfusion weighted images and reliability of BF measurements were satisfied. The 3D pCASL series with PLD of 1525 ms and 2025 ms have better image quality than PLD of 2525 ms. And BF values do not show significant statistic difference among the three groups. Therefore, 3D pCASL series with PLD of 1525 ms and 2025 ms are more suitable for the perfusion imaging of head and neck tumors


Assuntos
Neoplasias de Cabeça e Pescoço , Artefatos , Feminino , Humanos , Aumento da Imagem , Imageamento Tridimensional , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Razão Sinal-Ruído , Marcadores de Spin
12.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 36(1): 73-8, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24581133

RESUMO

OBJECTIVE: To investigate the value of diffusion-weighted imaging (DWI) in the differentiation of metastatic lymph nodes from non-metastatic lymph nodes in cervical cancer. METHODS: In 65 patients who underwent lymph node dissection for cervical cancer, conventional MRI and DWI examinations were performed before surgery. Of the 1590 total dissected pelvic lymph nodes, 392 enlarged nodes with a short-axis diameter (S )of 5 mm or greater were included for further analysis. Each of the size-based criteria [i.e., S, long-axis diameter (L), and S/L ratio] and apparent diffusion coefficient(ADC)-based criteria (i.e., ADCmin, ADCmean, rADCmin, rADCmean) were compared between metastatic lymph nodes and non-metastatic lymph nodes. RESULTS: There were statistically significant differences between metastatic and non-metastatic lymph nodes in S, L, S/L ratio, ADCmin, ADCmean, rADCmin, and rADCmean (all P<0.0001). The Az of the ADCmin (0.956) was greater than that of the other ADC-based criteria and all size-based criteria. Using ADCmin=759.0×10(-6) mm(2)/s, the sensitivity and specificity for differentiating metastatic from non-metastatic lymph nodes were 95.2% and 92.1%, respectively. CONCLUSION: DWI, particularly ADCmin, is feasible for differentiating metastatic from non-metastatic pelvic lymph nodes in patients with cervical cancer.


Assuntos
Imagem de Difusão por Ressonância Magnética , Linfonodos/patologia , Metástase Linfática/diagnóstico , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Sensibilidade e Especificidade
14.
J Phys Chem B ; 112(15): 4751-9, 2008 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-18366207

RESUMO

The influence of nanometer-scale interfaces on proteins has received much attention in recent years. The dynamic behaviors of bone morphogenetic protein-7 (BMP-7) on a series of hydroxyapatite (HAP) surface textures were investigated to explore the influence of different surface textures using molecular dynamics (MD), steered molecular dynamics simulations (SMD), and quantum mechanics calculations. It is observed that the interaction energy curve from SMD simulations can exhibit the dynamic behavior of BMP-7 in detail. Both the type and the number difference of the adsorptive residues and the intensity discrepancy of interaction, which is induced by the specific texture of the HAP surface, could be uncovered from the energy curve qualitatively and semiquantitatively in this study. The largest conformational change occurs in the system 010+a. The quantum mechanics calculations suggest that there is a phenomenon of electron transfer from HAP to the groups of BMP-7 during the adsorption process. These findings suggest that surface-engineering techniques could be employed to directly control the texture of HAP surfaces in order to regulate the behavior of a protein adsorbed onto the nanometer-scale interface.


Assuntos
Proteínas Morfogenéticas Ósseas/química , Hidroxiapatitas/química , Fator de Crescimento Transformador beta/química , Adsorção , Proteína Morfogenética Óssea 7 , Simulação por Computador , Modelos Químicos , Modelos Moleculares , Conformação Proteica , Teoria Quântica , Propriedades de Superfície , Fatores de Tempo
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