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Objective@#To investigate whether reader training improves the performance and agreement of radiologists in interpreting unenhanced breast magnetic resonance imaging (MRI) scans using diffusion-weighted imaging (DWI). @*Materials and Methods@#A study of 96 breasts (35 cancers, 24 benign, and 37 negative) in 48 asymptomatic women was performed between June 2019 and October 2020. High-resolution DWI with b-values of 0, 800, and 1200 sec/mm 2 was performed using a 3.0-T system. Sixteen breast radiologists independently reviewed the DWI, apparent diffusion coefficient maps, and T1-weighted MRI scans and recorded the Breast Imaging Reporting and Data System (BI-RADS) category for each breast. After a 2-h training session and a 5-month washout period, they re-evaluated the BI-RADS categories. A BI-RADS category of 4 (lesions with at least two suspicious criteria) or 5 (more than two suspicious criteria) was considered positive.The per-breast diagnostic performance of each reader was compared between the first and second reviews. Inter-reader agreement was evaluated using a multi-rater κ analysis and intraclass correlation coefficient (ICC). @*Results@#Before training, the mean sensitivity, specificity, and accuracy of the 16 readers were 70.7% (95% confidence interval [CI]: 59.4–79.9), 90.8% (95% CI: 85.6–94.2), and 83.5% (95% CI: 78.6–87.4), respectively. After training, significant improvements in specificity (95.2%; 95% CI: 90.8–97.5; P = 0.001) and accuracy (85.9%; 95% CI: 80.9–89.8; P = 0.01) were observed, but no difference in sensitivity (69.8%; 95% CI: 58.1–79.4; P = 0.58) was observed. Regarding inter-reader agreement, the κ values were 0.57 (95% CI: 0.52–0.63) before training and 0.68 (95% CI: 0.62–0.74) after training, with a difference of 0.11 (95% CI: 0.02–0.18; P = 0.01). The ICC was 0.73 (95% CI: 0.69–0.74) before training and 0.79 (95% CI: 0.76–0.80) after training (P = 0.002). @*Conclusion@#Brief reader training improved the performance and agreement of interpretations by breast radiologists using unenhanced MRI with DWI.
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This study aimed to evaluate the imaging and pathological findings in axillary lymph nodes in patients with breast cancer who received concurrent ipsilateral coronavirus disease 2019 (COVID-19) vaccination. Of the 19 women with breast cancer who received concurrent COVID-19 vaccination shot in the arm ipsilateral to breast cancer, axillary lymphadenopathy was observed in 84.2% (16 of 19) of patients on ultrasound (US) and 71.4% (10 of 14) of patients on magnetic resonance imaging (MRI), and 21.0% (4 of 19) of patients were diagnosed with metastasis. Abnormal US and MRI findings of cortical thickening, effacement of the fatty hilum, round shape, and asymmetry in the number or size relative to the contralateral side were noted in more than half of the non-metastatic and metastatic lymph nodes; however, statistical significance was not noted. Axillary lymphadenopathy is commonly observed in patients with breast cancer who receive concurrent ipsilateral COVID-19 vaccination without specific differential imaging features. Thus, understanding the limitations of axillary imaging and cautious interpretation is necessary to avoid overestimation or underestimation of the axillary disease burden.
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Myxoma is a benign mesenchymal neoplasm found in the heart, bone, and other soft tissues. However, myxoma of the external auditory canal is extremely rare. Since myxoma of the external auditory canal can be manifested as a part of the Carney complex, an autosomal dominant multiple familial neoplastic disorder, correct diagnosis and thorough investigation is important. We report a case of a 59-year-old man who presented to hospital with a complaint of growing mass within the right external auditory canal during one month. The surgical excision was done, and the histopathological examination revealed myxoma. In this article, we report the magnetic resonance imaging and computed tomography findings of the myxoma of the external auditory canal and correlate with the histopathological finding.
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beta-Glucosidase, which hydrolyzes cellobiose into two glucoses, plays an important role in the process of saccharification of the lignocellulosic biomass. In this study, we optimized the activity of beta-glucosidase of brown-rot fungus Fomitopsis pinicola KCTC 6208 using the response surface methodology (RSM) with various concentrations of glucose, yeast extract and ascorbic acid, which are the most significant nutrients for activity of beta-glucosidase. The highest activity of beta-glucosidase was achieved 3.02% of glucose, 4.35% of yeast extract, and 7.41% ascorbic acid where ascorbic acid was most effective. The maximum activity of beta-glucosidase predicted by the RSM was 15.34 U/mg, which was similar to the experimental value 14.90 U/mg at the 16th day of incubation. This optimized activity of beta-glucosidase was 23.6 times higher than the preliminary activity value, 0.63 U/mg, and was also much higher than previous values reported in other fungi strains. Therefore, a simplified medium supplemented with a cheap vitamin source, such as ascorbic acid, could be a cost effective mean of increasing beta-glucosidase activity.
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Ácido Ascórbico , beta-Glucosidase , Biomassa , Celobiose , Coriolaceae , Fungos , Glucose , Vitaminas , LevedurasRESUMO
A beta-glucosidase from Penicillium italicum was purified with a specific activity of 61.8 U/mg, using a chromatography system. The native form of the enzyme was an 88.5-kDa tetramer with a molecular mass of 354 kDa. Optimum activity was observed at pH 4.5 and 60degrees C, and the half-lives were 1,737, 330, 34, and 1 hr at 50, 55, 60, and 65degrees C, respectively. Its activity was inhibited by 47% by 5 mM Ni2+. The enzyme exhibited hydrolytic activity for p-nitrophenyl-beta-D-glucopyranoside (pNP-Glu), p-nitrophenyl-beta-D-cellobioside, p-nitrophenyl-beta-D-xyloside, and cellobiose, however, no activity was observed for p-nitrophenyl-beta-D-lactopyranoside, p-nitrophenyl-beta-D-galactopyranoside, carboxymetyl cellulose, xylan, and cellulose, indicating that the enzyme was a beta-glucosidase. The kcat/Km (s-1 mM-1) values for pNP-Glu and cellobiose were 15,770.4 mM and 6,361.4 mM, respectively. These values were the highest reported for beta-glucosidases. Non-competitive inhibition of the enzyme by both glucose (Ki = 8.9 mM) and glucono-delta-lactone (Ki = 11.3 mM) was observed when pNP-Glu was used as the substrate. This is the first report of non-competitive inhibition of beta-glucosidase by glucose and glucono-delta-lactone.
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beta-Glucosidase , Celobiose , Celulases , Celulose , Cromatografia , Citrus , Fungos , Glucose , Glucosídeos , Concentração de Íons de Hidrogênio , PenicilliumRESUMO
Factor XI deficiency (also called Hemophilia C) rarely occurs among ethnicities other than Ashkenazi Jews. A boy was scheduled for frontoethmoidectomy due to bilateral chronic rhinosinusitis. He was incidentally found to have factor XI deficiency due to prolonged aPTT on preoperative laboratory finding. His medical history reveals frequent epistaxis 2 or 3 times per day and his factor XI and XII activity were 17% (normal; 60-140%) and 34% (normal; 60-140%), respectively on furthermore laboratory evaluation. He was diagnosed as hereditary factor XI deficiency. He underwent the operation with administration of the fresh frozen plasma without complication.
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Humanos , Epistaxe , Fator XI , Deficiência do Fator XI , Hemofilia A , Judeus , PlasmaRESUMO
Ramsay Hunt syndrome is a disorder characterized by herpetic eruptions on the auricle, facial paralysis, and vestibulocochlear dysfunction, and is attributed to varicella zoster virus infection in the geniculate ganglion. Ramsay Hunt syndrome accounts for about 10% cases of facial palsy. We report a 46-year-old healthy man developed left side skin vesicles on the face with severe pain. We thought of the trigeminal herpes zoster. He was treated with intravenous acyclovir, and stellate ganglion block daily. Four days later, brain magnetic resonance imaging revealed small areas of enhancement in the seventh cranial nerve and eighth cranial nerve, not in the fifth cranial nerve. Eight days later, the left facial palsy was come. We confirmed him as Ramsay Hunt syndrome. We started steroid therapy immediately. He recovered completely a month later. The patient was improved through the early antiviral therapy, steroid medication and stellate ganglion block.