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1.
Acta Radiol ; 64(9): 2578-2589, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37593946

RESUMO

BACKGROUND: Accurate differentiation of nodular fasciitis (NF) from soft tissue sarcoma (STS) before surgery is essential for the subsequent diagnosis and treatment of patients. PURPOSE: To develop and evaluate radiomics nomograms based on clinical factors and magnetic resonance imaging (MRI) for the preoperative differentiation of NF from STS. MATERIAL AND METHODS: This retrospective study analyzed the MRI data of 27 patients with pathologically diagnosed NF and 58 patients with STS who were randomly divided into training (n = 62) and validation (n = 23) groups. Univariate and multivariate analyses were performed to identify the clinical factors and semantic features of MRI. Radiomics analysis was applied to fat-suppressed T1-weighted (T1W-FS) images, fat-suppressed T2-weighted (T2W-FS) images, and contrast-enhanced T1-weighted (CE-T1W) images. The radiomics nomograms incorporating the radiomics signatures, clinical factors, and semantic features of MRI were developed. ROC curves and AUCs were carried out to compare the performance of the clinical factors, radiomics signatures, and clinical radiomics nomograms. RESULTS: Tumor location, size, heterogeneous signal intensity on T2W-FS imaging, heterogeneous signal intensity on CE-T1W imaging, margin definitions on CE-T1W imaging, and septa were independent predictors for differentiating NF from STS (P < 0.05). The performance of the radiomics signatures based on T2W-FS imaging (AUC = 0.961) and CE-T1W imaging (AUC = 0.938) was better than that based on T1W-FS imaging (AUC = 0.833). The radiomics nomograms had AUCs of 0.949, which demonstrated good clinical utility and calibration. CONCLUSION: The non-invasive clinical radiomics nomograms exhibited good performance in the differentiation of NF from STS, and they have clinical application in the preoperative diagnosis of diseases.


Assuntos
Fasciite , Sarcoma , Neoplasias de Tecidos Moles , Humanos , Nomogramas , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Sarcoma/diagnóstico por imagem , Neoplasias de Tecidos Moles/diagnóstico por imagem , Fasciite/diagnóstico por imagem
2.
J Ultrasound Med ; 42(3): 649-664, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35851691

RESUMO

PURPOSE: The objective of this research was to develop and validate an ultrasound-based radiomics nomogram for the pre-operative assessment of Ki-67 in breast cancer (BC). MATERIALS AND METHODS: From December 2016 to December 2018, 515 patients with invasive ductal breast cancer who received two-dimensional (2D) ultrasound and Ki-67 examination were studied and analyzed retrospectively. The dataset was distributed at random into a training cohort (n = 360) and a test cohort (n = 155) in the ratio of 7:3. Each tumor region of interest was defined based on 2D ultrasound images and radiomics features were extracted. ANOVA, maximum correlation minimum redundancy (mRMR) algorithm, and minimum absolute shrinkage and selection operator (LASSO) were performed to pick features, and independent clinical predictors were integrated with radscore to construct the nomogram for predicting Ki-67 index by univariate and multivariate logistic regression analysis. The performance and utility of the models were evaluated by plotting receiver operating characteristic (ROC) curves, decision curve analysis (DCA), and calibration curves. RESULTS: In the testing cohort, the area under the receiver characteristic curve (AUC) of the nomogram was 0.770 (95% confidence interval, 0.690-0.860). In both cohorts, the nomogram outperformed both the clinical model and the radiomics model (P < .05 according to the DeLong test). The analysis of DCA proved that the model has clinical utility. CONCLUSIONS: The nomogram based on 2D ultrasound images offered an approach for predicting Ki-67 in BC.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Antígeno Ki-67 , Nomogramas , Estudos Retrospectivos , Ultrassonografia
3.
Skeletal Radiol ; 50(8): 1677-1686, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33532939

RESUMO

OBJECTIVE: To investigate the diagnostic value of conventional ultrasound (US) and strain elastography (SE) in malignant soft tissue tumors. METHOD: A total of 83 soft tissue masses were included prospectively. US and SE imaging were performed at the same time. Two observers assessed the B mode, color Doppler, elastic scores (ES), strain ratio (SR), and SE size to B mode size (EI/B) ratio and compared the consistency of the data between the observers. According to the pathological diagnosis of resection, the cases were divided into malignant and nonmalignant groups. The diagnostic value of conventional US and SE in the prediction of malignant soft tissue tumors was assessed. RESULTS: The pathology results divided cases into 36 malignant lesions and 47 nonmalignant lesions. There was no statistically significant difference in gender, location, maximum diameter, echo, tail sign, cystic component, Doppler scores, or SR between the two groups (p > 0.05). However, significant differences between the two groups were found in age, depth, heterogeneity, edge, ES, and EI/B (p < 0.05). The biggest area under the receiver operating characteristics curve (0.934) was the combination model of age, heterogeneity, edge, ES, and EI/B, and the sensitivity and specificity were 0.861 and 0.957, respectively. CONCLUSIONS: Conventional US and SE are significant for the diagnosis of malignant soft tissue tumors, and SE can be used as a complementary technique to the characterization of STTs using conventional US.


Assuntos
Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Neoplasias de Tecidos Moles , Diagnóstico Diferencial , Feminino , Humanos , Sensibilidade e Especificidade , Neoplasias de Tecidos Moles/diagnóstico por imagem , Ultrassonografia
4.
Skeletal Radiol ; 49(11): 1829-1838, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32519183

RESUMO

OBJECTIVE: To determine if dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) parameters reflect histological grade of soft tissue sarcoma (STS) MATERIALS AND METHODS: The medical records of 50 patients diagnosed with pathologically confirmed STS were retrospectively reviewed. Each STS was assessed with conventional contrast-enhanced MRI and DCE-MRI using a 3.0-T MRI system. The conventional MRI characteristics of low-grade (grade 1) and high-grade (grade 2 and grade 3) tumors were analyzed. Semi-quantitative parameters, including iAUC and TTP, and quantitative parameters, including Ktrans, Kep, and Ve, were derived from DCE-MRI. The diagnostic performances and optimal thresholds of various combinations of DCE-MRI parameters for predicting histological grades of STS were investigated using receiver operator characteristic (ROC) curves. RESULTS: On conventional MRI, high-grade STSs were significantly larger (≥ 5 cm) and more likely to show a heterogeneous signal intensity on T2WI (> 75%), peritumoral hyperintensity on T2WI, or tumor necrosis (> 50%) compared with low-grade STS. On DCE-MRI, iAUC, TTP, Ktrans, and Kep were significant predictors of STS histological grade. Ktrans had a high diagnostic value for differentiating between high-grade and low-grade STSs. The combination of iAUC, TTP, and Ktrans yielded a higher AUC value (0.841) than the other models. CONCLUSION: High-grade STSs were usually larger than low-grade STSs, had unclear boundaries, a heterogeneous signal intensity on T2-weighted image (T2WI), and extensive necrosis. On DCE-MRI, iAUC, TTP, Ktrans, and Kep could differentiate between high-grade and low-grade STSs. The combination of iAUC, TTP, and Ktrans had a high diagnostic performance for differentiating between STS histological grades.


Assuntos
Imageamento por Ressonância Magnética , Sarcoma , Neoplasias de Tecidos Moles , Meios de Contraste , Humanos , Estudos Retrospectivos , Sarcoma/diagnóstico por imagem , Neoplasias de Tecidos Moles/diagnóstico por imagem
5.
3 Biotech ; 11(9): 418, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34603918

RESUMO

Three genes encoding AfsK, AfsR, AfsS homologues in Streptomyces pristinaespiralis were studied, respectively, to investigate regulatory role of AfsKRS system for pristinamycin biosynthesis. Transcription change and gene inactivation analysis indicated that these genes had active transcription and positive regulation for the improvement of pristinamycin production in S. pristinaespiralis. The analysis of AfsKRS-defective mutagenesis indicated that there might be a positive correlation between the product of afsK and pristinamycin I biosynthesis, and a negative correlation to pristinamycin II biosynthesis. However, both afsR and afsS might have negative correlation to pristinamycin I production and positive correlation to pristinamycin II production. The effects on pristinamycin production of AfsKRS disruptants by protein kinase inhibitor K252a indicated that AfsR, both not AfsK and AfsS, was the inhibition target of K252a in S. pristinaespiralis, and AfsR should serve as a pleiotropic regulator to have differential regulation on biosynthesis of pristinamycin I and II components. Based on above study, it might be deduced that different signal transduction patterns via AfsK, AfsR, AfsS of AfsKRS system should be involved in respective regulation for biosynthesis of pristinamycin I and II in S. pristinaespiralis. In conclusion, the investigation could give some valuable clues for exploring furtherly regulatory function of AfsKRS system in S. pristinaespiralis.

6.
3 Biotech ; 9(5): 194, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31065494

RESUMO

A novel gene (crc1) from Candida boidinii was cloned and then overexpressed in a recombinant strain BL21(DE3)/pET30a-crc1 of Escherichia coli. The resulting carbonyl reductase was prepared through fermentations using the recombinant strain. The purified enzyme showed an NADPH-dependent activity and specific activity was 4.65 U/mg using t-butyl 6-cyano-(5R)-hydroxy-3-oxohexanoate (ATS-6) as substrate. The enzyme was optimally active at 35 °C and pH 7, respectively. The apparent K m and V max of the enzyme for ATS-6 are 1.5 mM and 21.1 µmol/min mg, respectively, indicating excellent anti-Prelog stereospecificity. Under the optimum condition, t-butyl 6-cyano-(3R,5R)-dihydroxyhexanoate (ATS-7) was prepared with the enzyme with high d.e. value (99.9%) and good conversion (94%) in 4 h, indicating high stereoselectivity and conversion efficiency in biotransformation of ATS-6 to ATS-7.

7.
Eur J Obstet Gynecol Reprod Biol ; 205: 174-88, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27620811

RESUMO

BACKGROUND: Endometriosis is a common, benign gynecological disorder affecting life quality of reproductive-aged women. Several polymorphisms in the promoter regions of the MMPs genes have been reported that were related to endometriosis risk. However, there are many contradictory conclusions, and no meta-analysis focused on this association systematically. OBJECTIVES: To evaluate the associations between various possible polymorphisms of MMPs genes and endometriosis risk, and confirm which kinds of MMPs genetic polymorphisms are associated with endometriosis risk, in order to identify the etiology and pathogenesis of endometriosis and the potential effective markers for predicting the predisposition to endometriosis. SEARCH STRATEGY: An exhaustive electronic literature search was conducted, using keywords MMP, endometriosis and SNP, in English and Chinese. SELECTION CRITERIA: All eligible case-control studies by written in English or Chinese of the associations of MMPs polymorphisms with endometriosis risk, which had sufficient data for examining an odds ratio (OR) with 95% confidence interval (CI), were identified up to March 1, 2015. DATA COLLECTION AND ANALYSIS: A total of 1833 patients and 2190 controls from 12 studies were included. Allele frequency differences between cases and controls were performed with the use of odds ratios (ORs) and their respective 95% confidence intervals (CIs) for five genetic models. MAIN RESULTS: For MMP-1 -1607 1G>2G (rs1799750) polymorphism, significant associations were observed both in overall comparison and subgroup analyses based on the stage of endometriosis, ethnicity of each study population and method of genotyping under four genetic models. In contrast, for MMP-2 15918 T>C (rs243847), MMP-2 -753 C>T (rs2285053), MMP-7 -181 A>G (rs11568818), MMP-9 -1562 C>T (rs3918242) and MMP-9 R279Q (rs17576) polymorphisms, no association was found in overall comparison, but in subgroup analyses based on source of control, stage of endometriosis, or ethnicity. CONCLUSIONS: MMP-1 -1607 1G>2G polymorphism might modulate risk of endometriosis, so does the MMP-2 15918 T>C, MMP-2 -753 C>T, MMP-7 -181 A>G, MMP-9 -1562 C>T and MMP-9 R279Q polymorphisms in some subgroups.


Assuntos
Endometriose/genética , Predisposição Genética para Doença , Metaloproteinases da Matriz/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Feminino , Frequência do Gene , Genótipo , Humanos
8.
Opt Express ; 13(6): 1855-9, 2005 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-19495066

RESUMO

Longitudinal and transverse microholes are drilled in soda-lime glass by water-assisted ablation with femtosecond laser pulses. True three-dimensional microchannels consisting of longitudinal and transverse microholes are presented. At low incident pulse energy, only one transverse microhole is observed. At high incident pulse energy, multiple transverse microholes can be simultaneously drilled. Using a focusing lens with numerical aperture of 0.5, two, three and four transverse microholes are fabricated at 3.2, 4.9 and 9.3microJ/pulse, which is qualitatively explained by the multiple foci process.

9.
Opt Express ; 13(7): 2433-8, 2005 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-19495134

RESUMO

We present a novel technique to directly fabricate permanent computer-generated holograms inside silica glass with femtosecond laser pulses. The Fourier transform of an object is performed using a computer and the complex amplitude distribution is encoded by the detour phase method. The resulted cell-oriented hologram is directly written inside a bulk of silica glass by femtosecond laser-induced microexplosion. The image is then reconstructed with a collimated He-Ne laser beam.

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