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BackgroundIdentifying the MIC wild-type distribution and its delineation of species targeted for receiving antimicrobial agent breakpoints is an important first step for determining clinical breakpoints. Having the main responsibility in the European Committee on Antimicrobial Susceptibility Testing (EUCAST) for characterizing the wild-type distributions and setting epidemiological cut-off values (ECOFFs), we explain the why, the how, and frequent misconceptions of wild-type MIC distributions and ECOFFs.ObjectivesTo clarify how wild-type MIC distributions and ECOFFs for agents and important target organisms are defined and determined and why these are important tools in microbiology, as well as to point to common misunderstandings and inappropriate use.SourcesThe EUCAST database of >40 000 MIC distributions; publications addressing the definition of wild-type MIC distributions, and ECOFFs in bacteria and fungi; and the EUCAST Standard Operating Procedure 10 Documents published by the European Centre for Disease Control and the European Food Safety Agency.ContentThe rationale for defining wild-type distributions and ECOFFs is explained. Setting breakpoints that bisect wild-type MIC distributions leads to poor methodological reproducibility and poor correlation between clinical outcome and susceptibility testing results. The methods applied by EUCAST to select distributions for aggregation and website display are described, highlighting the importance of incorporating data from multiple sources and methods. The methods used by EUCAST to estimate ECOFFs are outlined. Finally, the common misunderstandings of these processes are addressed.ImplicationsThe international community needs to agree on the phenotypic definitions of wild-type distributions. Systematic methods for developing and applying ECOFFs are essential to the conduct of phenotypic antimicrobial susceptibility testing and interpretation, which will remain the dominant laboratory method for the foreseeable future.  相似文献   
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目的 研究干扰素-γ(IFN-γ)对食管鳞状细胞癌细胞株Eca9706增殖及迁移能力的影响,并初步探讨其作用机制。方法 体外进行细胞培养,用干扰素-γ作用细胞,镜下观察细胞形态变化,CCK-8实验检测细胞增殖能力,划痕实验和Transwell实验检测细胞迁移能力。采用Quantitative RealtimePCR法检测趋化因子CXCL8(白介素8)的表达效率,ELISA实验检测细胞CXCL8分泌量的变化。结果 与空白对照组比较,接受不同浓度干扰素-γ作用后的Eca9706细胞,细胞形态未发生明显改变。CCK-8实验证实,IFN-γ作用后的Eca9706细胞增殖能力显著降低(P<0.01)。划痕实验发现IFN-γ使Eca9706细胞迁移能力显著下降(P<0.01)。Transwell实验显示IFN-γ作用后,Eca9706细胞的迁移能力受到明显抑制(P<0.01)。同时,接受干扰素-γ作用后,Eca9706细胞的CXCL8基因表达水平显著下调(P<0.01),CXCL8分泌量显著降低(P<0.05 ) 。结论 干扰素-γ可抑制食管癌细胞株Eca9706的增殖和迁移能力,其可能与抑制Eca9706细胞的CXCL8的表达和分泌相关。  相似文献   
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《Clinical breast cancer》2022,22(6):560-566
BackgroundIn the United States, Europe, and Asia, a consensus has been reached that there is a higher risk of breast cancer in high density breasts. However, there are some contrary reports that suggest the absence of an association between breast composition and breast cancer subtype; thus, there is conflicting evidence. The purpose of this study was to investigate trends in the incidence of breast cancer subtypes according to breast composition and analyze the survival rates in Japanese women.Patients and MethodsBetween 2007 and 2008, 1258 Japanese patients with invasive breast cancer who underwent mammography and obtained a pathological diagnosis in our institution were included in the study. We compared cancer subtypes with breast composition types (dense and non-dense breast), and classified them based on initial mammography findings. Information on 5- and 10-year survival rates was collected by chart review for patients with dense and nondense breasts. Statistical analysis was performed using the Pearson's chi-square test for breast composition and cancer subtype. The effect of breast composition on mortality was examined using a multivariate Cox proportional hazards model, and adjusted hazard ratios were calculated.ResultsNo significant difference was found between breast cancer subtype and breast composition (P = .08). Five-year (log-rank test, P = .09) and 10-year (log-rank test, P = .31) survival rates were not significantly different between breast composition types.ConclusionThere was no significant association between breast composition and cancer subtypes. There was also no significant difference in the prognosis between patients with and without dense breasts.  相似文献   
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Mass characteristic frequency (fmass) is a novel shear wave (SW) parameter that represents the ratio of the averaged minimum SW speed within the regions of interest to the largest dimension of the mass. Our study objective was to evaluate if the addition of fmass to conventional 2-D shear wave elastography (SWE) parameters would improve the differentiation of benign from malignant thyroid nodules. Our cohort comprised 107 patients with 113 thyroid nodules, of which 67 (59%) were malignant. Two-dimensional SWE data were obtained using the Supersonic Imagine Aixplorer ultrasound system equipped with a 44- to 15-MHz15-MHz linear array transducer. A receiver operating characteristic curve was generated based on a multivariable logistic regression analysis to evaluate the ability of SWE parameters with/without fmass and with/without clinical factors to discriminate benign from malignant thyroid nodules. The addition of fmass to conventional SW elasticity parameters increased the area under the curve from 0.808 to 0.871 (p = 0.02). The combination of SW elasticity parameters plus fmass plus clinical factors provided the strongest thyroid nodule malignancy probability estimate, with a sensitivity of 93.4% and specificity of 91.1% at the optimal threshold. In summary, fmass can be a valuable addition to conventional 2-D SWE parameters.  相似文献   
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ObjectiveWe encountered a case of high-grade serous carcinoma (HGSC) of the ovary which recurred as carcinosarcoma of the sigmoid colon. Tumor cells of both the primary carcinoma and the secondary carcinosarcoma were negative for estrogen receptor (ER), WT-1, and PAX8. It is well known that most ovarian carcinomas arising from the Müllerian duct are immunoreactive for these biologic parameters. To our knowledge, this is the first case report that provides the results of immunohistochemical analysis of WT-1 and PAX8 for a primary carcinoma and recurrent carcinosarcoma.Case reportA 61-year-old woman had an advanced right ovarian HGSC. After a primary debulking surgery (hysterectomy, bilateral salpingo-oophorectomy and omentectomy) and adjuvant chemotherapy, complete remission was achieved. However, four and a half years later, a tumor arising beside the sigmoid colon was detected. A tumorectomy was performed through combined partial resection of the ileum and sigmoid colon. Microscopically, the tumor was diagnosed as carcinosarcoma of the sigmoid colon, which had originated from HGSC of the ovary. Interestingly, the malignant cells of the primary carcinoma and epithelial components of the recurrent carcinosarcoma were negative for ER, WT-1, and PAX8. These immunohistochemical features were unusual. Three cycles of chemotherapy with the previously used regimen and three additional cycles of doxorubicin and ifosfamide combination chemotherapy were administered. Currently, 3 years after the final chemotherapy was administered, the patient remains healthy.ConclusionHGSC of the ovary can recur as carcinosarcoma. Tumor cells of the primary HGSC without ER, WT-1, and PAX8 expression may have dedifferentiated and recurred as carcinosarcoma.  相似文献   
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