Clumped vs non-clumped internal enhancement patterns in linear non-mass enhancement on breast MRI

Objective:To compare positive predictive values (PPVs) of clumped vs non-clumped (homogenous and heterogeneous) internal enhancement on MRI detected linear non-mass enhancement (NME) on MRI-guided vacuum-assisted breast biopsy (MRI-VABB).Methods:With IRB (Institutional Review Board) approval, we retrospectively reviewed 598 lesions undergoing MRI-VABB from January 2015 to April 2018 that showed linear NME. We reviewed the electronic medical records for MRI-VABB pathology, any subsequent surgery and clinical follow-up. The X² test was performed for univariate analysis.Results:There were 120/598 (20%) linear NME MRI-VABB lesions with clumped (52/120, 43%) vs non-clumped (68/120, 57%) internal enhancement, average size 1.8 cm (range 0.6–7.6 cm). On MRI-VABB, cancer was identified in 22/120 (18%) lesions, ductal carcinoma in situ (DCIS) was found in 18/22 (82%) and invasive cancer in 4 (18%). 3/31 (10%) high-risk lesions upgraded to DCIS at surgery, for a total of 25/120 (21%) malignancies. Malignancy was found in 12/52 (23%) clumped lesions and in 13/68 (19%) of non-clumped lesions that showed heterogeneous (5/13, 38%) or homogenous (8/13, 62%) internal enhancement. The PPV of linear NME with clumped internal enhancement (23.1%) was not significantly different from the PPV of non-clumped linear NME (19.1%) (p = 0.597). The PPV of linear NME lesions <1 cm (33.3%) was not significantly different from the PPV of lesions ≥1 cm (18.6%) (p = 0.157).Conclusions:Linear NME showed malignancy in 21% of our series. Linear NME with clumped or non-clumped internal enhancement patterns, regardless of lesion size, might need to undergo MRI-VABB in appropriate populations.Advances in knowledge:Evaluation of linear NME lesions on breast MRI focuses especially on internal enhancement pattern.     

强迫症的认知理论

强迫症的主要特征是强迫观念和强迫行为,患者有意识的自我强迫和自我反强迫共存。认知理论对强迫症的解释和治疗得到了大量的实证研究的支持。强迫信念对闯入性思想的评价是强迫症状得以发展和恶化的重要因素。几个有影响力的强迫症的认知模型分别介绍了不同的强迫信念是如何导致强迫症状的。可以采用认知治疗技术克服强迫思维。     

Recovery of Oral In Vitro Biofilms after Exposure to Peptides and Chlorhexidine

IntroductionThis study aimed to examine the dynamic recovery of established multispecies biofilms of oral bacteria after an initial treatment by D-enantiomeric peptide DJK-5, L-enantiomeric peptide 1018, or chlorhexidine digluconate (CHX).MethodsOral biofilms from 2 donors were grown on collagen-coated hydroxyapatite disks for 3 weeks and exposed to DJK-5, 1018, and 2% CHX for 3 minutes. Immediately after treatment and 1, 2, 3, 5, 7, 8, and 12 weeks after exposure, the biofilm volume and the volume ratio of dead and live bacteria in biofilms were assessed by confocal laser scanning microscopy using a live/dead viability stain. Results were examined by 1-way analysis of variance and post hoc multiple comparisons to determine significance at a P < .05 significance level.ResultsDJK-5 killed almost 80% of biofilms in 3 minutes and maintained this high level of dead bacteria for 1 week. The proportion of viable bacteria in DJK-5–treated biofilms returned to the pretreatment level after 12 weeks. The biovolume of DJK-5–treated biofilm remained significantly lower than that of biofilms after CHX and no treatment throughout the 12-week follow-up period (P < .001). The proportion of dead bacteria was higher in biofilms exposed to DJK-5 than with 1018 or CHX for 8 weeks after the exposure (P < .001). The proportion of dead bacteria almost doubled to 46%–52% during the first 7 days after the 3-minute exposure to CHX and peptide 1018. The timeline of biofilm recovery was slow but similar after exposure to CHX and the 2 peptides.Conclusionsecovery time after exposure to DJK-5 was longer than that after exposure to 1018 and CHX. Peptide 1018 showed a delayed, continued antibacterial effect similar to that of 2% CHX against the biofilm microbes.     

元认知与大学生心理和谐的关系

目的 探讨元认知与大学生心理和谐的关系.方法 采用元认知问卷和心理和谐问卷,对507名大学生进行测评.结果 ①大学生元认知水平与心理和谐水平性别差异均不显著;②大一学生心理和谐水平显著高于大二、大三学生(F=5.70,P＜0.01).大二学生心理和谐水平高于大三学生,但差异不显著;③回归分析表明,元认知对大学生心理和谐各维度及心理和谐总体水平具有显著的预测作用(β=0.431～0.587,P＜0.01).结论 元认知是大学生心理和谐的重要影响因素.     

Optimization of Polymer Solar Cells Based on the Conjugated Copolymer of Poly(phenylenevinylene‐alt‐4,7‐diphenyl‐2,1,3‐benzothiadiazole) (PP‐DBT)

Polymer solar cells based on poly(phenylenevinylene‐alt‐4,7‐diphenyl‐2,1,3‐benzothiadiazole) (PP‐DBT):[6,6]‐phenyl C₇₁ butyric acid methyl‐ester (PC₇₁BM) blend films are optimized. The results show that the solar cell has a better performance at a 1:4 blend ratio than at 1:1, 1:2, 1:3, and 1:5 blend ratios, due to the higher hole mobility of active layer and the optimized morphology. The device prepared from chlorobenzene (CB) has a higher power conversion efficiency (PCE) than the devices prepared from chloroform and o‐dichlorobenzene, because the former has a much higher short‐circuit current density (J_sc) resulting from the morphology with proper phase separation. The solar cell modified with two layers of ZnO nanocrystals achieves the best performance with an open‐circuit voltage of 0.9 V, a J_sc of 7.46 mW cm^?2, fill factor (FF) of 0.50, and PCE of 3.36%.