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1.
Cogn Emot ; 37(4): 852-862, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37132215

RESUMO

In the process of decision-making based on conferring with advisors, people are sensitive to advisors' emotional expressions. An advisor's expression is considered a type of feedback. The quick detection of motivational or valence significance of feedback has been associated with feedback-related negativity (FRN). In this study, we investigated how decision makers evaluated advice that was distant from the original estimate provided by advisors with different emotional expressions based on behavioural, FRN, and P300 data. The results showed that participants were more likely to modify their initial estimates based on advice from advisors with happy expressions than from advisors with angry expressions, regardless of whether it was near-distance advice or far-distance advice. When facing far-distance advice, FRN amplitudes in angry-expression conditions were significantly larger than in happy-expression conditions. When facing near-distance advice, there was no significant difference in the FRN amplitude between happy- and angry-expression conditions. P300 amplitudes were larger in near-distance conditions than in far-distance conditions. These findings suggest that, as a type of feedback with social information, the advisor's face will affect the decision maker's evaluation of the advice, with a happy face of the advisor serving as correct feedback and an angry face serving as incorrect feedback.


Assuntos
Ira , Eletroencefalografia , Humanos , Felicidade , Motivação , Tomada de Decisões
2.
Rapid Commun Mass Spectrom ; 35(3): e8999, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33140453

RESUMO

RATIONALE: The screening for illegal adulteration of glucocorticoids (GCs) in cosmetics is challenging due to the vast variety of potential GCs that are present to improve the declared effects. An effective analytical method to screen illegally added GCs in cosmetics is vital to protect consumers. METHODS: An ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) method using precursor ion scanning (PIS) acquisition mode was developed to screen GCs in cosmetics. Forty-seven GCs were investigated to identify their common product ions formed by collision-induced dissociation. Cosmetic samples spiked with GCs were extracted using solid-phase extraction. RESULTS: Four common positive product ions, m/z 121, 135, 147, and 171, were selected for PIS analysis. Limits of detection (LODs) were established for all 47 GCs. The method was validated on spiked samples to ensure its effectiveness in terms of sensitivity and selectivity. Sixty samples were analyzed. Seven GCs were detected in six samples. CONCLUSIONS: An effective screening method using UPLC/MS/MS with PIS acquisition mode was developed and successfully applied to screen for targeted and untargeted GCs in cosmetic samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cosméticos/análise , Glucocorticoides/análise , Espectrometria de Massas em Tandem/métodos , Qualidade de Produtos para o Consumidor , Contaminação de Medicamentos/legislação & jurisprudência , Humanos , Limite de Detecção
3.
Pharmacol Res ; 141: 530-540, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30660821

RESUMO

Glial activation and scar formation impede the neurological function recovery after cerebral ischemia. Oleoylethanolamide (OEA), a bioactive lipid mediator, shows neuroprotection against acute brain ischemia, however, its long-term effect, especially on glial scar formation, has not been characterized. In this research, we investigate the effect of OEA on glial activation and scar formation after cerebral ischemia in vitro and in vivo experiments. Glial scar formation in vitro model was induced by transforming growth factor ß1 (TGF-ß1) in C6 glial cell culture, and experiment model in vivo was induced by middle cerebral artery occlusion (MCAO) in mice. The protein expressions of the markers of glial activation (S100ß, GFAP, or pSmads) and glial scar (neurocan) were detected by Western blot and/or immunofluorescence staining; To evaluate the role of PPARɑ in the effect of OEA on glial activation, the PPARɑ antagonist GW6471 was used. Behavior tests were used to assay the effect of OEA on motor function recovery 14 days after brain ischemia in mice. Our results show that OEA (10-50 µM) concentration-dependently inhibited the upregulation of S100ß, GFAP, pSmads and neurocan induced by TGF-ß1 in C6 glial cells. At the same time, OEA promoted the protein expression and nuclear transportation of PPARɑ in glial cells. PPARα antagonist GW6471 abolished the effect of OEA on glial activation. In addition, we found that delay administration of OEA inhibited the astrocyte activation and promoted the recovery of motor function after brain ischemia in mice. These results indicate that OEA may be developed into a new candidate for attenuating astrocytic scar formation and improving motor function after ischemic stroke.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Endocanabinoides/uso terapêutico , Neuroglia/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Ácidos Oleicos/uso terapêutico , PPAR alfa/metabolismo , Animais , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Linhagem Celular , Endocanabinoides/farmacologia , Força da Mão , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Camundongos , Neuroglia/metabolismo , Neuroglia/patologia , Fármacos Neuroprotetores/farmacologia , Ácidos Oleicos/farmacologia , Ratos , Recuperação de Função Fisiológica , Caminhada
4.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3246-3252, 2019 Aug.
Artigo em Zh | MEDLINE | ID: mdl-31602879

RESUMO

Inula japonica was used as the research object, "3414" fertilization experiment were conducted to study the effects of nitrogen,phosphorus and potassium formula fertilizer on the growth and chemical composition content of I. japonica. The characteristics of fertilizer requirement were preliminarily revealed and the study provided fertilization guidance for artificial cultivation of I. japonica. The results showed that different nitrogen,phosphorus and potassium formula fertilizers had significant effects on plant morphology,physiological and biochemical indexes,dry matter accumulation and chemical composition content. The growth indexes and chemical components of I. japonica showed an upward trend with the increase of fertilization amount,especially the nitrogen fertilizer was the most significant. The indicators were analyzed by membership function. After comprehensive evaluation,the optimal nitrogen,phosphorus and potassium formula fertilization level was N3 P2 K2,namely high level nitrogen fertilizer,medium level phosphorus fertilizer and potassium fertilizer. I. japonica is a high fertilizer demand plant,and the rational fertilization scheme is " applying nitrogen fertilizer again and applying phosphorus and potassium fertilizer properly".


Assuntos
Fertilizantes , Inula/crescimento & desenvolvimento , Nitrogênio/química , Fósforo/química , Potássio/química , Inula/química
5.
Org Biomol Chem ; 14(31): 7447-50, 2016 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-27431277

RESUMO

We report herein a highly efficient intramolecular coupling reaction of tertiary amines and ketones (α,ß-unsaturated ketones) by using a Brønsted acid as a cocatalyst, affording 2-arylindols in good to excellent yields (up to 92%) under visible light irradiation at room temperature.

6.
Chemistry ; 21(52): 18921-4, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26559029

RESUMO

An unprecedented remote construction of chiral vicinal tertiary and quaternary centers by a catalytic asymmetric 1,6-conjugate addition of prochiral carbon nucleophiles to cyclic dienones has been developed. Both 5H-oxazol-4-ones and 2-oxindoles were found to be very efficient carbon nucleophiles in this reaction at a remote position, giving products with excellent enantio- and diastereoselectivities (up to 99% ee and >19:1 d.r. for 5H-oxazol-4-ones and up to 97% ee and >19:1 d.r. for 2-oxindoles).

7.
RSC Adv ; 14(5): 3122-3134, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38249670

RESUMO

Bacterial infections from chronic wounds affect about 175 million people each year and are a significant clinical problem. Through the integration of photodynamic therapy (PDT) and chemotherapy, a new photosensitizer consisting of ammonium salt N,N-bis-(2-hydroxyethyl)-N-(6-(4-(10,15,20-trimesitylporphyrin-5-yl) phenoxy) hexane)-N-methanaminium bromide, TMP(+) was successfully synthesized with a total reaction yield of 10%. The novel photosensitizer consists of two parts, a porphyrin photosensitizer part and a quaternary ammonium salt part, to achieve the synergistic effect of photodynamic and chemical antibacterial activity. With the increase of TMP(+) concentration, the diameter of the PCT fiber membranes (POL/COL/TMP(+); POL, polycaprolactone; COL, collagen) gradually increased, which was caused by the charge of the quaternary ammonium salt. At the same time, the antibacterial properties were gradually improved. We finally selected the PCT 0.5% group for the antibacterial experiment, with excellent performance in fiber uniformity, hydrophobicity and biosafety. The antibacterial experiment showed that the modified porphyrin TMP(+) had a better antibacterial effect than others. In vivo chronic wound healing experiments proved that the antibacterial and anti-inflammatory effect of the PCTL group was the best, further confirmed by H&E histological analysis, immunofluorescence and immunohistochemistry mechanism experiments. This research lays the foundation for the manufacture of novel molecules that combine chemical and photodynamic strategies.

8.
Mitochondrial DNA B Resour ; 8(3): 414-417, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36969326

RESUMO

Leuciscus merzbacheri (Zugmayer, 1912) is a cyprinid fish endemic to China, with a distribution range limited to Xinjiang Province. As a landmark species in the Junggar Basin, L. merzbacheri is of considerable significance regarding our understanding of the adaptive evolution of salt and alkali tolerance. In this study, the complete mitochondrial sequence of L. merzbacheri was obtained for the first time by high-throughput sequencing. The circular mitogenome is 16,609 bp in length and contains the standard 37 genes, including 13 protein-coding, 22 transfer RNA, and 2 ribosomal RNA genes, which is similar to that of other fish. The mitogenome contents of A, T, C, and G were 27.9, 26.3, 27.1, and 18.7%, respectively. Phylogenetically, L. merzbacheri was located on a new branch near the base of the phylogenetic tree, thereby suggesting an early origin.

9.
Biomedicines ; 11(3)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36979952

RESUMO

Astrocyte inflammation activation is an important cause that hinders the recovery of motor function after cerebral ischemia. However, its molecular mechanism has not yet been clearly clarified. The peroxisome proliferator-activated receptor α (PPARα) is a ligand-activated nuclear transcriptional factor. This study aims to further clarify the role of PPARα in astrocyte inflammation activation after cerebral ischemia and to explore the underlying mechanism. Astrocyte activation was induced in an in vivo model by transient middle cerebral artery occlusion (tMCAO) in mice. The in vitro model was induced by an oxygen-glucose deprivation/reoxygenation (OGD/R) in a primary culture of mouse astrocyte. PPARα-deficient mice were used to observe the effects of PPARα on astrocyte activation and autophagic flux. Our results showed that PPARα was mainly expressed in activated astrocytes during the chronic phase of brain ischemia and PPARα dysfunction promoted astrocyte inflammatory activation. After cerebral ischemia, the expressions of LC3-II/I and p62 both increased. Autophagic vesicle accumulation was observed by electron microscopy in astrocytes, and the block of autophagic flux was indicated by an mRFP-GFP-LC3 adenovirus infection assay. A PPARα deficit aggravated the autophagic flux block, while PPARα activation preserved the lysosome function and restored autophagic flux in astrocytes after OGD/R. The autophagic flux blocker bafilomycin A1 and chloroquine antagonized the effect of the PPARα agonist on astrocyte activation inhibition. This study identifies a potentially novel function of PPARα in astrocyte autophagic flux and suggests a therapeutic target for the prevention and treatment of chronic brain ischemic injury.

10.
Eur J Pharmacol ; 957: 175982, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37572942

RESUMO

Ischemic stroke is a leading cause of death and disability, and medical treatments for ischemic stroke are very limited. URB597 is a potent and selective inhibitor of fatty acid amide hydrolase (FAAH). However, the effect of URB597 on ischemic stroke and the underlying molecular mechanisms remain little known. In this study, focal cerebral ischemia was induced by transient middle cerebral artery occlusion in mice. Our results showed that URB597 dose-dependently improved neurological function and reduced brain infarct volume and brain edema 24 h after brain ischemia. The most effective dose was 1 mg/kg and the therapeutic time window was within 3 h after ischemic stroke. To further investigate the underlying mechanism, necroptosis and autophagy flux were detected by Western blot and/or immunofluorescence staining with or without chloroquine, an autophagic flux inhibitor. Our results showed that URB597 promoted autophagic flux and reduced neuronal necroptosis after brain ischemia and these effects could be abolished by chloroquine. In addition, we found that peroxisome proliferator-activated receptor α (PPARα) antagonist GW6471 partly abolished the effect of URB597 against brain ischemia and URB597 upregulated the expressions of PPARα. In conclusion, URB597 exerts a neuroprotective effect in a dose- and time-dependent manner, and this effect may be related to its restoration of autophagic flux and inhibition of neuronal necroptosis. PPARα is involved in the neuroprotective effect of URB597. This study provides novel evidence that URB597 may be a promising agent for the clinical treatment of ischemic stroke.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , Fármacos Neuroprotetores , Ratos , Camundongos , Animais , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , PPAR alfa/metabolismo , Necroptose , Ratos Sprague-Dawley , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Autofagia , Cloroquina/farmacologia , Cloroquina/uso terapêutico
11.
Insights Imaging ; 14(1): 145, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37697217

RESUMO

OBJECTIVES: Posthepatectomy liver failure (PHLF) is a severe complication of liver resection. We aimed to develop and validate a model based on extracellular volume (ECV) and liver volumetry derived from computed tomography (CT) for preoperative predicting PHLF in resectable hepatocellular carcinoma (HCC) patients. METHODS: A total of 393 resectable HCC patients from two hospitals were enrolled and underwent multiphasic contrast-enhanced CT before surgery. A total of 281 patients from our hospital were randomly divided into a training cohort (n = 181) and an internal validation cohort (n = 100), and 112 patients from another hospital formed the external validation cohort. CT-derived ECV was measured on nonenhanced and equilibrium phase images, and liver volumetry was measured on portal phase images. The model is composed of independent predictors of PHLF. The under the receiver operator characteristic curve (AUC) and calibration curve were used to reflect the predictive performance and calibration of the model. Comparison of AUCs used the DeLong test. RESULTS: CT-derived ECV, measured future liver remnant (mFLR) ratio, and serum albumin were independent predictors for PHLF in resectable HCC patients. The AUC of the model was significantly higher than that of the ALBI score in the training cohort, internal validation cohort, and external validation cohort (all p < 0.001). The calibration curve of the model showed good consistency in the training cohort and the internal and external validation cohorts. CONCLUSIONS: The novel model contributes to the preoperative prediction of PHLF in resectable HCC patients. CRITICAL RELEVANCE STATEMENT: The novel model combined CT-derived extracellular volume, measured future liver remnant ratio, and serum albumin outperforms the albumin-bilirubin score for predicting posthepatectomy liver failure in patients with resectable hepatocellular carcinoma. KEY POINTS: • CT-derived ECV correlated well with the fibrosis stage of the background liver. • CT-derived ECV and mFLR ratio were independent predictors for PHLF in HCC. • The AUC of the model was higher than the CT-derived ECV and mFLR ratio. • The model showed a superior predictive performance than that of the ALBI score.

12.
Int J Biol Macromol ; 247: 125504, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37356692

RESUMO

Preventing wound infection is a major challenge in biomedicine. Conventional wound dressings often have poor moisturizing and antimicrobial properties unfavorable for wound healing. In this study, we prepared a multifunctional electrospun nanofiber dressing (PCQX-M) containing xyloglucan, quaternized chitosan, Polyvinyl alcohol, and collagen. By applying the concept of wet healing, xyloglucan and quaternized chitosan polysaccharides with excellent water solubility were employed to improve the absorption and moisturizing properties and maintain a moist microenvironment for the wound healing process. PCQX-M demonstrated high mechanical, thermodynamic, and biocompatible properties, providing suitable healing conditions for wounds. In addition, PCQX-M showed exceptional antibacterial properties and a potential inhibitory effect on the growth of microorganisms in infected wounds. More intriguingly, the restorative healing effect was investigated on a mouse model of whole skin injury infected with Staphylococcus aureus. Wound healing, collagen deposition, and immunofluorescence results showed that PCQX-M significantly promoted cell proliferation and angiogenesis at the injury site and facilitated the healing of the infected wound. Our study suggests that PCQX-M has excellent potential for clinical application in infected wound healing.


Assuntos
Quitosana , Nanofibras , Infecção dos Ferimentos , Camundongos , Animais , Quitosana/farmacologia , Cicatrização , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bandagens/microbiologia , Colágeno/farmacologia , Infecção dos Ferimentos/tratamento farmacológico
13.
Radiother Oncol ; 171: 107-113, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35461950

RESUMO

BACKGROUND AND PURPOSE: It remains uncertain whether induction chemotherapy (IC) plus concurrent chemoradiotherapy (CCRT) or CCRT plus adjuvant chemotherapy (AC) is more effective in patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC). This study aimed to develop and validate a joint radiomic and clinical signature (RCS) for the prognostic stratification of LA-NPCs and to identify patients who might benefit more from IC + CCRT or CCRT + AC. MATERIALS AND METHODS: Overall, 893 LA-NPC patients who received IC + CCRT or CCRT + AC were enrolled from four hospitals. RCS based on pretreatment magnetic resonance images and clinical data was constructed for predicting 5-year progression-free survival (PFS). The predictive ability of the RCS and TNM staging system for 5-year PFS, locoregional relapse-free survival (LRRFS), distant metastasis-free survival (DMFS) and overall survival (OS) were compared by Harrell's concordance indices (C-indices). Patients were divided into high- and low-risk subgroups based on RCS scores. The survival benefit of IC + CCRT vs. CCRT + AC in different subgroups was compared by Kaplan-Meier survival curves. RESULTS: The RCS combining the radiomic signature, TNM stage and EBV DNA demonstrated significantly higher C-indices than TNM stage for predicting 5-year PFS, LRRFS, DMFS and OS in the training and validation cohorts. In the high-risk group (RCS score ≥ 0.25), CCRT + AC achieved significantly better PFS, LRRFS, DMFS and OS than IC + CCRT. In the low-risk group (RCS score < 0.25), IC + CCRT yielded significantly better outcomes than CCRT + AC. CONCLUSION: The RCS provides a noninvasive way to predict the outcomes of LA-NPC and helps identify patients who may benefit more from IC + CCRT vs. CCRT + AC.


Assuntos
Quimioterapia de Indução , Neoplasias Nasofaríngeas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/métodos , Quimioterapia Adjuvante/métodos , Humanos , Quimioterapia de Indução/métodos , Imageamento por Ressonância Magnética , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/terapia , Recidiva Local de Neoplasia/tratamento farmacológico
14.
Quant Imaging Med Surg ; 12(2): 1243-1256, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35111620

RESUMO

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) patients with a high tumor grade, lymphovascular invasion (LVI), or perineural invasion (PNI) tend to demonstrate a poor prognosis in clinical series. Thus, the identification of histopathological features, including tumor grade, LVI, and PNI, before treatment could be used to stratify the prognosis of patients with HNSCC. This study aimed to assess whether quantitative parameters derived from pretreatment dual-energy computed tomography (DECT) can predict the histopathological features of patients with HNSCC. METHODS: In this study, 72 consecutive patients with pathologically confirmed HNSCC were enrolled and underwent dual-phase (noncontrast-enhanced phase and contrast-enhanced phase) DECT examinations. Normalized iodine concentration (NIC), the slope of the spectral Hounsfield unit curve (λHU), and normalized effective atomic number (NZeff) were calculated. The attenuation values on 40-140 keV noise-optimized virtual monoenergetic images [VMIs (+)] in the contrast-enhanced phase were recorded. The diagnostic performance of the quantitative parameters for predicting histopathological features, including tumor grade, LVI, and PNI, was assessed by receiver operating characteristic curves. RESULTS: The NIC, λHU, NZeff, and attenuation value on the VMIs (+) at 40 keV (A40) in the grade III group, LVI-positive group, and PNI-positive group were significantly higher than those in the grade I and II groups, the LVI-negative group, and the PNI-negative group (all P values <0.05). A multivariate logistic regression model combining these 4 quantitative parameters improved the diagnostic performance of the model in predicting tumor grade, LVI, and PNI (areas under the curve: 0.969, 0.944, and 0.931, respectively). CONCLUSIONS: Quantitative parameters derived from pretreatment DECT, including NIC, λHU, NZeff, and A4,0 were found to be imaging markers for predicting the histopathological characteristics of HNSCC. Combining all these characteristics improved the predictive performance of the model.

15.
Insights Imaging ; 13(1): 85, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35507098

RESUMO

OBJECTIVES: To assess the value of myocardial extracellular volume (ECV) derived from contrast-enhanced chest computed tomography (CT) for longitudinal evaluation of cardiotoxicity in patients with breast cancer (BC) treated with anthracycline (AC). MATERIALS AND METHODS: A total of 1151 patients with BC treated with anthracyclines, who underwent at least baseline, and first follow-up contrast-enhanced chest CT were evaluated. ECV and left ventricular ejection fraction (LVEF) were measured before (ECV0, LVEF0), during ((ECV1, LVEF1) and (ECV2, LVEF2)), and after (ECV3, LVEF3) AC treatment. ECV values were evaluated at the middle of left ventricular septum on venous phase images. Cancer therapy-related cardiac dysfunction (CTRCD) was recorded. RESULTS: Mean baseline LVEF values were 65.85% ± 2.72% and 102 patients developed CTRCD. The mean ECV0 was 26.76% ± 3.03% (N0 = 1151). ECV1, ECV2, and ECV3 (median interval: 61 (IQR, 46-75), 180 (IQR, 170-190), 350 (IQR, 341-360) days from baseline) were 31.32% ± 3.10%, 29.60% ± 3.24%, and 32.05% ± 3.58% (N1 = 1151, N2 = 841, N3 = 511). ECV1, ECV2, and ECV3 were significantly higher than ECV0 (p < 0.001). ECV0 and ECV1 showed no difference between CTRCD (+) and CTRCD (-) group (p1 = 0.150; p2 = 0.216). However, ECV2 and ECV3 showed significant differences between the two groups (p3 < 0.001; p4 < 0.001). CONCLUSION: CT-derived ECV is a potential biomarker for dynamic monitoring AC cardiotoxicity in patients with BC.

16.
Eur J Radiol ; 136: 109532, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33450663

RESUMO

OBJECTIVES: To determine the optimal kiloelectron volt of noise-optimized virtual monoenergetic images [VMI (+)] for visualization of nasopharyngeal carcinoma (NPC) and nasopharyngeal lymphoma (NPL), and to explore the clinical value of quantitative parameters derived from dual-energy computed tomography (DECT) for distinguishing the two entities. MATERIALS AND METHODS: Eighty patients including 51 with NPC and 29 with NPL were enrolled. The VMIs (+) at 40-80 keV with an interval of 10 keV were reconstructed by contrast enhanced images. The overall image quality and demarcation of lesion margins, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were assessed in VMIs (+) and polyenergetic images (PEI). Normalized iodine concentration (NIC), slope of the spectral Hounsfield unit curve (λHU) and effective atomic number (Zeff) were calculated. Diagnostic performance was assessed by receiver operating characteristic (ROC) curve. RESULTS: The 40 keV VMI (+) yielded highest overall image quality scores, demarcation of lesion margins scores, SNR and CNR. The values of NIC, λHU and Zeff in NPL were higher than those in NPC (P <  0.001). Multivariate logistic regression model combining NIC, λHU and Zeff showed the best performance for distinguishing NPC from NPL (AUC: 0.947, sensitivity: 93.1 % and specificity: 92.2 %). CONCLUSION: VMI (+) reconstruction at 40 keV was optimal for visualizing NPC and NPL. Quantitative parameters derived from DECT were helpful for differentiating NPC from NPL.


Assuntos
Linfoma , Neoplasias Nasofaríngeas , Imagem Radiográfica a Partir de Emissão de Duplo Fóton , Algoritmos , Humanos , Linfoma/diagnóstico por imagem , Carcinoma Nasofaríngeo/diagnóstico por imagem , Neoplasias Nasofaríngeas/diagnóstico por imagem , Estudos Retrospectivos , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X
17.
Quant Imaging Med Surg ; 11(9): 4004-4015, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34476185

RESUMO

BACKGROUND: Stage T1 nasopharyngeal carcinoma (NPCT1) and benign hyperplasia (BH) are 2 common causes of nasopharyngeal mucosa/submucosa thickening without specific clinical symptoms. The treatment management of these 2 entities is significantly different. Reliable differentiation between the 2 entities is critical for the treatment decision and prognosis of patients. Therefore, our study aims to explore the optimal energy level of noise-optimized virtual monoenergetic images [VMI (+)] derived from dual-energy computed tomography (DECT) to display NPCT1 and BH and to explore the clinical value of DECT for differentiating these 2 diseases. METHODS: A total of 91 patients (44 NPCT1, 47 BH) were enrolled. The demarcation of the lesion margins and overall image quality, noise, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR) were evaluated for 40-80 kiloelectron volts (keV) VMIs (+) and polyenergetic images in the contrast-enhanced phase. Image features were assessed in the contrast-enhanced images with optimal visualization of NPCT1 and BH. The demarcation of NPCT1 and BH in iodine-water maps was also assessed. The contrast-enhanced images were used to calculate the slope of the spectral Hounsfield unit curve (λHU) and normalized iodine concentration (NIC). The nonenhanced phase images were used to calculate the normalized effective atomic number (NZeff). The attenuation values on 40-80 keV VMIs (+) in the contrast-enhanced phase were recorded. The diagnostic performance was assessed using receiver operating characteristic (ROC) curve analysis. RESULTS: The 40 keV VMI (+) in the enhanced phase yielded higher demarcation of the lesion margins scores, overall image quality scores, noise, SNR, and CNR values than 50-80 keV VMIs (+) and polyenergetic images. NPCT1 yielded higher attenuation values on VMI (+) at 40 keV (A40), NIC, λHU, and NZeff values than BH. The multivariate logistic regression model combining image features (tumor symmetry) with quantitative parameters (A40, NIC, λHU, and NZeff) yielded the best performance for differentiating the 2 diseases (AUC: 0.963, sensitivity: 89.4%, specificity: 93.2%). CONCLUSIONS: The combination of DECT-derived image features and quantitative parameters contributed to the differentiation between NPCT1 and BH.

18.
Clin Imaging ; 79: 119-124, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33940488

RESUMO

OBJECTIVES: We aimed to evaluate the feasibility of simultaneous multi-slice readout segmentation of long variable echo-trains (SMS-RESOLVE) for diffusion-weighted imaging (DWI) of nasopharyngeal carcinoma (NPC) and determine the optimal acceleration factor of SMS-RESOLVE DWI compared with conventional RESOLVE DWI. MATERIALS AND METHODS: One hundred and five patients with histologically confirmed NPC were enrolled. DWIs including conventional RESOLVE DWI, SMS-RESOLVE DWI with acceleration factors of 2 and 3 (2 × SMS-RESOLVE and 3 × SMS-RESOLVE) were acquired at b-values of 0 and 800 s/mm2. The subjective image quality, including overall image quality, lesion conspicuity, and lesion distortion scores, and objective image quality, including signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and contrast in these three protocols, were assessed and compared. The apparent diffusion coefficients (ADCs) of the primary tumor and right masseter muscle and normalized ADCs in the three protocols were measured and compared. RESULTS: The 2 × SMS-RESOLVE provided comparable image quality and ADCs with a 48.3% reduction in scan time compared with conventional RESOLVE DWI. The 3 × SMS-RESOLVE showed significantly poorer image quality and the highest ADCs with a 56.9% reduction in scan times compared with conventional RESOLVE DWI. CONCLUSION: The SMS-RESOLVE DWI with an acceleration factor of 2 yielded the best compromise between image quality and scan time reduction and could be an alternative to conventional RESOLVE DWI for nasopharyngeal carcinoma.


Assuntos
Imagem Ecoplanar , Neoplasias Nasofaríngeas , Imagem de Difusão por Ressonância Magnética , Estudos de Viabilidade , Humanos , Carcinoma Nasofaríngeo/diagnóstico por imagem , Neoplasias Nasofaríngeas/diagnóstico por imagem , Reprodutibilidade dos Testes
20.
Org Lett ; 19(9): 2322-2325, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28445064

RESUMO

The first example of a photoexcitated amine-catalyzed process for asymmetric Michael addition of o-quinodimethanes to enones is described. In the presence of simple chiral amino acid esters, a variety of Michael adducts were generally obtained in good yields and excellent stereoselectivities. This strategy can be successfully applied to 3-substituted-2-cyclohexenones and provides an asymmetric access to all-carbon quaternary centers. Furthermore, the high stereocontrol was explained by means of density-functional theory (DFT) calculations.

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