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1.
Eur Radiol ; 34(8): 5349-5359, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38206403

RESUMO

OBJECTIVES: To develop and assess a radiomics-based prediction model for distinguishing T2/T3 staging of laryngeal and hypopharyngeal squamous cell carcinoma (LHSCC) METHODS: A total of 118 patients with pathologically proven LHSCC were enrolled in this retrospective study. We performed feature processing based on 851 radiomic features derived from contrast-enhanced CT images and established multiple radiomic models by combining three feature selection methods and seven machine learning classifiers. The area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, and specificity were used to assess the performance of the models. The radiomic signature obtained from the optimal model and statistically significant morphological image characteristics were incorporated into the predictive nomogram. The performance of the nomogram was assessed by calibration curve and decision curve analysis. RESULTS: Using analysis of variance (ANOVA) feature selection and logistic regression (LR) classifier produced the best model. The AUCs of the training, validation, and test sets were 0.919, 0.857, and 0.817, respectively. A nomogram based on the model integrating the radiomic signature and a morphological imaging characteristic (suspicious thyroid cartilage invasion) exhibited C-indexes of 0.899 (95% confidence interval (CI) 0.843-0.955), fitting well in calibration curves (p > 0.05). Decision curve analysis further confirmed the clinical usefulness of the nomogram. CONCLUSIONS: The nomogram based on the radiomics model derived from contrast-enhanced CT images had good diagnostic performance for distinguishing T2/T3 staging of LHSCC. CLINICAL RELEVANCE STATEMENT: Accurate T2/T3 staging assessment of LHSCC aids in determining whether laryngectomy or laryngeal preservation therapy should be performed. The nomogram based on the radiomics model derived from contrast-enhanced CT images has the potential to predict the T2/T3 staging of LHSCC, which can provide a non-invasive and robust approach for guiding the optimization of clinical decision-making. KEY POINTS: • Combining analysis of variance with logistic regression yielded the optimal radiomic model. • A nomogram based on the CT-radiomic signature has good performance for differentiating T2 from T3 staging of laryngeal and hypopharyngeal squamous cell carcinoma. • It provides a non-invasive and robust approach for guiding the optimization of clinical decision-making.


Assuntos
Neoplasias Hipofaríngeas , Neoplasias Laríngeas , Aprendizado de Máquina , Estadiamento de Neoplasias , Nomogramas , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Hipofaríngeas/diagnóstico por imagem , Neoplasias Hipofaríngeas/patologia , Masculino , Feminino , Neoplasias Laríngeas/diagnóstico por imagem , Neoplasias Laríngeas/patologia , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Idoso , Adulto , Sensibilidade e Especificidade , Meios de Contraste , Idoso de 80 Anos ou mais , Radiômica
2.
J Pain Res ; 17: 2629-2638, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39155954

RESUMO

Purpose: Zoster-associated pain (ZAP) is frequently concomitant with psychiatric comorbidities. However, the underlying neuropathological mechanisms of ZAP with psychiatric comorbidities remain poorly understood. Patients and Methods: Rest-stating functional MRI (rs-fMRI) data from 41 ZAP patients without anxiety or depression (noA/D-ZAP), 11 ZAP patients with anxiety or depression (A/D-ZAP) and 29 healthy controls (HCs) were acquired. Degree centrality (DC) based on rs-fMRI was used to explore the node changes in the brain functional network in these subjects. Moreover, correlations and receiver operating characteristic curve analysis were performed. Results: One-way analysis of variance revealed abnormal DC values in the right middle frontal gyrus (MFG) and bilateral precuneus among the three groups. Compared with HCs, A/D-ZAP showed increased DC values in the bilateral pons, while noA/D-ZAP showed increased DC values in the right pons, left brainstem and rectal gyrus and decreased DC values in the right cingulate gyrus and bilateral precuneus. A/D-ZAP showed increased DC values in the left MFG and precentral gyrus (PG) compared with noA/D-ZAP. The DC value of the left pons in A/D-ZAP was positively correlated with the self-rating anxiety scale score. Areas under the curve of DC values in the left PG and MFG for distinguishing A/D-ZAP from the noA/D-ZAP group were 0.907 and 1.000, respectively. Conclusion: This study revealed the node differences in the brain functional network of ZAP patients with or without psychiatric comorbidities. In particular, abnormal DC values of the left MFG and PG may play an important role in the neuropathologic mechanism of the disease.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38735428

RESUMO

It is of vital importance to establish an objective and reliable model to facilitate the early diagnosis and intervention of internet gaming disorder (IGD). A total of 133 patients with IGD and 110 healthy controls (HCs) were included. We extracted radiomic features of subcortical structures in high-resolution T1-weighted MRI. Different combinations of four feature selection methods (analysis of variance, Kruskal-Wallis, recursive feature elimination and relief) and ten classification algorithms were used to identify the most robust combined models for distinguishing IGD patients from HCs. Furthermore, a nomogram incorporating radiomic signatures and independent clinical factors was developed. Calibration curve and decision curve analyses were used to evaluate the nomogram. The combination of analysis of variance selector and logistic regression classifier identified that the radiomic model constructed with 20 features from the right caudate nucleus and amygdala showed better IGD screening performance. The radiomic model produced good areas under the curves (AUCs) in the training, validation and test cohorts (AUCs of 0.961, 0.903 and 0.895, respectively). In addition, sex, internet addiction test scores and radiomic scores were included in the nomogram as independent risk factors for IGD. Analysis of the correction curve and decision curve showed that the clinical-radiomic model has good reliability (C-index: 0.987). The nomogram incorporating radiomic features of subcortical structures and clinical characteristics achieved satisfactory classification performance and could serve as an effective tool for distinguishing IGD patients from HCs.


Assuntos
Transtorno de Adição à Internet , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Humanos , Masculino , Transtorno de Adição à Internet/diagnóstico por imagem , Feminino , Imageamento por Ressonância Magnética/métodos , Adulto Jovem , Adulto , Nomogramas , Encéfalo/diagnóstico por imagem , Núcleo Caudado/diagnóstico por imagem , Núcleo Caudado/patologia , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Radiômica
4.
Braz J Microbiol ; 54(2): 1093-1102, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37145298

RESUMO

Heracleum vicinum Boiss., a perennial plant of Angelica in Umbelliferae, is mainly distributed in Sichuan and Hunan of China. Trichophyton rubrum is a common skin fungus causing dermatophyte. The previous experimental study found that the ethanol extract from Heracleum vicinum Boiss. had excellent anti-Trichophyton rubrum activity, especially the ethanol extract further extracted with petroleum ether and dichloromethane has the best antibacterial effect and has good potential for treating dermatophytes. In this study, Heracleum vicinum Boiss. was extracted with ethanol by microwave-assisted ultrasonic extraction method and isolated with silica gel column to obtain a coumarin compound M1-1 by the guidance of anti-Trichophyton rubrum activity, which was characterized by nuclear magnetic resonance spectroscopy(13C-NMR), hydrogen nuclear magnetic resonance (1H-NMR), Fourier transform infrared spectroscopy (FTIR), high-resolution mass spectrometry (HR-ESI-MS), and ultraviolet (UV) and identified as imperatorin and belonged to coumarins, with the minimum inhibitory concentration (MIC) against Trichophyton rubrum of 12.5 µg/mL. According to the discussion on the inhibitory mechanism of the compound, we found that the compound may exert its inhibitory effect by destroying the mycelial membrane and inhibiting the mycelial growth of Trichophyton rubrum. In a word, imperatorin isolated from Heracleum vicinum Boiss. is expected to be used as an antibacterial agent to treat dermatophytes a potential natural compound against Trichophyton rubrum, and a template for drug development of dermatophytes the future.


Assuntos
Arthrodermataceae , Heracleum , Cumarínicos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Etanol/farmacologia , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana
5.
Materials (Basel) ; 13(15)2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32707847

RESUMO

The effect of different precipitate microstructures obtained by different heat treatments on fatigue behavior of 7020 aluminum alloy was investigated. The fine Guinier Preston I (GPI) zones in the under-aged alloy can be repeatedly sheared by dislocations produced in cyclic loading, making the fatigue crack initiate difficultly and fatigue crack path propagate tortuously. Fatigue strength and fatigue crack propagation resistance of the alloy with shearable precipitates are much higher than those of the alloy with unshearable precipitates. The peak-aged alloy with continuous grain boundary precipitate (GBP) and narrow precipitate free zone (PFZ) is prone to initiate fatigue cracks and reduce fatigue strength. With the growth of unshearable precipitates, the fatigue strength of the alloy firstly increases and then decreases. Precipitates with moderate size in the over-aged alloy improve the roughness-induced crack closure (RICC) effect. Soft matrix with appropriate width between the precipitates can promote the slip reversibility and relax the crack tip stress. The fatigue strength of the moderately over-aged alloy reaches to 122.1 MPa at 107 cycles of loading, and the fatigue crack growth rate (FCGR) is 35.6% slower than that of the peak-aged alloy at ΔK of 10 MPa·m1/2.

6.
Materials (Basel) ; 12(24)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31842351

RESUMO

The microstructures and mechanical properties of friction stir welded (FSW) Al-Zn-Mg alloy plate under different travel speeds were investigated. Both the average grain sizes (AGSs) of the shoulder affected zone (SAZ), nugget zone (NZ), and the widths of thermo-mechanically affected zone (TMAZ) decreased with the increase of travel speed. Moreover, the AGSs of NZ are always about 60% of that of SAZ at different travel speeds. The fractions of high-angle grain boundaries (HAGBs) in the FSW joints reduce with the distance away from the stir zone (SZ). Furthermore, the initial η' strengthening precipitates in NZ and TMAZ dissolve and GP zones form during subsequent natural aging, so that the hardness is similar in the two zones. The precipitate evolution in the heat-affected zone (HAZ) at hardness minima are affected by travel speeds, which induce the hardness minima and ultimate tensile strength (UTS) of FSW joints and increase with the increase of travel speed, and a fracture tends to occur at hardness minima location of HAZ during tensile testing.

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