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Proteases play a crucial role in industrial enzyme formulations, with activity fluctuations significantly impacting product quality and yield. Therefore, developing a method for precise and rapid detection of protease activity is paramount. This study aimed to develop a rapid and accurate method for quantifying trypsin activity using integrated infrared (IR) and ultraviolet (UV) spectroscopy combined with data fusion techniques. The developed method evaluates the enzymatic activity of trypsin under varying conditions, including temperature, pH, and ionic strength. By comparing different data fusion methods, the study identifies the optimal model for accurate enzyme activity prediction. The results demonstrated significant improvements in predictive performance using the feature-level data fusion approach. Additionally, substituting the spectral data of the samples in the validation sets into the best prediction model resulted in a minimal residual difference between predicted and true values, further verifying the model's accuracy and reliability. This innovative approach offers a practical solution for the efficient and precise quantification of enzyme activity, with broad applications in industrial processes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The reactions involving enzymes are significantly influenced by various environmental factors. Clarity of how the activity and structure of proteases impact their function is crucial for more efficient application of enzymes as a tool. The impact of temperature, pH, and ionic strength on changes in protease activity, secondary structure, and protein conformation during enzymatic hydrolysis were investigated in this study. The enzymatic activity and secondary structure of acid-base protease were found to undergo significant modifications under different physical conditions, as demonstrated by UV spectrophotometry and FTIR spectroscopy analysis. Specifically, variations in α-helix and β-fold content were observed to correlate with changes in enzyme activity. Molecular simulation analysis revealed that physical conditions have varying effects on the protease, particularly influencing enzyme activity and secondary structure. Evaluation of the proteases indicated alterations in both enzyme activity and structure. This treatment selectively hydrolyzed β-lactoglobulin and reduced sensitization. These findings offer novel perspectives on the functionalities and regulatory mechanisms of proteases, as well as potential industrial applications., Competing Interests: Declaration of competing interest All the authors declare that he/she has no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Human epidermal growth factor receptor2+ subtype breast cancer has a high degree of malignancy and a poor prognosis. The aim of this study is to develop a prediction model for the human epidermal growth factor receptor2+ subtype (non-luminal) of breast cancer based on the clinical and ultrasound features related with estrogen receptor, progesterone receptor, and human epidermal growth factor receptor2., Methods: We collected clinical data and reviewed preoperative ultrasound images of enrolled breast cancers from September 2017 to August 2020. We divided the data into in three groups as follows. Group I: estrogen receptor ± , Group II: progesterone receptor ± and Group III: human epidermal growth factor receptor2 ± . Univariate and multivariate logistic regression analyses were used to analyze the clinical and ultrasound features related with biomarkers among these groups. A model to predict human epidermal growth factor receptor2+ subtype was then developed based on the results of multivariate regression analyses, and the efficacy was evaluated using the area under receiver operating characteristic curve, accuracy, sensitivity, specificity., Results: The human epidermal growth factor receptor2+ subtype accounted for 138 cases (11.8%) in the training set and 51 cases (10.1%) in the test set. In the multivariate regression analysis, age ≤ 50 years was an independent predictor of progesterone receptor + (p = 0.007), and posterior enhancement was a negative predictor of progesterone receptor + (p = 0.013) in Group II; palpable axillary lymph node, round, irregular shape and calcifications were independent predictors of the positivity for human epidermal growth factor receptor-2 in Group III (p = 0.001, p = 0.007, p = 0.010, p < 0.001, respectively). In Group I, shape was the only factor related to estrogen receptor status in the univariate analysis (p < 0.05). The area under receiver operating characteristic curve, accuracy, sensitivity, specificity of the model to predict human epidermal growth factor receptor2+ subtype breast cancer was 0.697, 60.14%, 72.46%, 58.49% and 0.725, 72.06%, 64.71%, 72.89% in the training and test sets, respectively., Conclusions: Our study established a model to predict the human epidermal growth factor receptor2-positive subtype with moderate performance. And the results demonstrated that clinical and ultrasound features were significantly associated with biomarkers., (© 2021. The Author(s).)

Objective: To investigate the frequency of KRAS mutation in mucinous epithelial lesions of the endometrium, and analyze the correlation between KRAS mutation and the clinicopathologic features. Methods: The cohort included forty-three cases of mucinous epithelial lesions of the endometrium selected from July 2015 to October 2017 from Beijing Obstetrics and Gynecology Hospital, and 22 control cases. Genomic DNA was extracted from formalin-fixed paraffin-embedded tissue sections. Polymerase chain reaction amplification for KRAS exons 2 and 3 was performed, followed by sequencing using capillary electrophoresis. The Fisher exact test was used to compare the prevalence of KRAS mutation among the different groups. Results: The patients'age ranged from 33 to 77 years [mean (55.12±9.34) years, median 55 years]. None of the eight cases of endometrial hyperplasia with mucinous differentiation without atypia showed KRAS mutation. The frequency of KRAS mutations was 1/10 in endometrial atypical hyperplasia, 1/12 in endometrioid carcinoma, 4/11 in endometrial atypical hyperplasia with mucinous differentiation (EAHMD), 6/15 in endometrioid carcinoma with mucinous differentiation (ECMD) and 8/9 in mucinous carcinoma (MC), respectively. The differences were statistically significant between MC versus EC ( P <0.01) and MC versus ECMD ( P <0.05). Conclusion: The high frequency of KRAS mutation in EAHMD, ECMD and MC indicates that KRAS mutational activation is implicated in the pathogenesis of endometrial mucinous carcinoma.

Objectives: We aimed to investigate the diagnostic performance of shear wave elastography (SWE) combined with conventional ultrasonography (US) for differentiating between benign and malignant thyroid nodules of different sizes., Methods: A total of 445 thyroid nodules from 445 patients were divided into 3 groups based on diameter (group 1, ≤ 10 mm; group 2, 10-20 mm; and group 3, > 20 mm). The mean elasticity index of the whole lesion was automatically calculated, and the threshold for differentiation between benign and malignant nodules was constructed by a receiver operating characteristic curve analysis. Diagnostic performances of conventional US and SWE were compared by using pathologic results as reference standards., Results: The mean elasticity was significantly higher in malignant versus benign nodules for all size groups. The differences in mean elasticity in the size groups were not statistically significant for malignant or benign nodules. The specificity of US combined with SWE for group 1 was significantly higher than that for groups 2 and 3 (77.8% versus 62.9% and 53.3%; P < .05), and compared with group 1, the sensitivity was significantly higher for groups 2 and 3 (92.4% and 94.3% versus 80.7%; P < .05). When SWE was added, the specificity increased and the sensitivity and diagnostic accuracy decreased for group 1, and the sensitivity increased and the specificity decreased for groups 2 and 3; however, the differences were not significant., Conclusions: Combined with SWE, US yielded higher specificity for nodules of 10 mm and smaller and higher sensitivity for nodules larger than 10 mm., (© 2017 by the American Institute of Ultrasound in Medicine.)

Objective: To study the signs of subclavian artery angiography for hemoptysis due to pulmonary tuberculosis and to evaluate its clinical use in artery embolization., Methods: Thirty-nine patients with hemoptysis due to pulmonary tuberculosis underwent subclavian artery angiography after artery embolization performed in the hemorrhagic branches of descending aorta. Of the 39 cases, 25 had severe pulmonary fibrosis or were complicated with cavity formation, aspergilloma, pleural thickening and postoperative thorax. The signs of subclavian artery angiography were divided into three categories: (-), normal; (+), the branches of subclavian artery and axillary artery chaotic and hyperplasia; (+ +), the branches of subclavian artery and axillary artery appeared tortuosity, dilatation, aneurysm and shunt with pulmonary circulation. Signs of bleeding was designated (+) and (+ +), with (+ +) indicating strongly positive. The signs of subclavian artery angiography were studied and statistically analyzed. Artery embolization was performed in some of the patients, among whom 15 were analyzed for long-term clinical curative effect., Results: Signs of positive bleeding was found in 32/39 of the cases, and strongly positive bleeding in 17/39 of the cases. Positive bleeding arteries accounted for 39/58 of the branches, including 24/58 (+ +) and 15/58 (+). Angiography demonstrated that the internal mammary artery, lateral thoracic artery and subscapular artery were the main hemorrhagic arteries. Patients with severe pulmonary fibrosis or complicated with cavity, aspergilloma, pleural thickening and postoperative thorax showed higher rate of positive and strongly positive bleeding. Artery embolization was performed in 15 cases: cure was achieved in 6, effective in 7 and failure in 2 cases. Of the 15 cases, 8 had been ineffective after embolization of the hemorrhagic branches of descending aorta alone., Conclusions: Our results suggest that corresponding subclavian artery angiography should be performed after the hemorrhagic branches of descending aorta artery have been embolized for hemoptysis due to pulmonary tuberculosis, especially in cases with failed embolization, or complicated with severe pulmonary fibrosis, cavity formation, aspergilloma, pleural thickening, or postoperative thorax. The hemorrhagic arteries shown by subclavian artery angiography must be embolized.