The Diagnostic Ability of rs-DWI to Detect Subtle Acute Infarction Lesion in the Different Regions of the Brain and the Comparison between Different b-Values

Objective. To evaluate the diagnostic ability of rs-DWI to detect subtle acute infarction lesion in the different regions of the brain in comparison to routine DWI and the comparison between different b-values. Method. 35 acute brain infarction patients were included. The subtle acute infarction lesions in ss-DWI and rs-DWI sequence were evaluated in 9 anatomical regions of the brain, and the ss-EPI DWI was also acquired with different b-values of 0, 1000, 2000, and 3000s/mm2. The McNemar test was performed for comparing the diagnostic ability of ss-DWI and rs-DWI and different b-values. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for the whole brain and in each anatomical region were calculated. Result. A total of 406 subtle acute infarction lesions were confirmed. The ss-DWI detected 338 subtle lesions, out of which 318 were true positive and 20 were false positive lesions. The rs-DWI detected 386 subtle lesions, out of which 385 were true positive lesions and 1 was true negative lesion. Sensitivity, specificity, positive predictive value, and negative predictive value in rs-DWI were better than ss-DWI in all anatomical regions of the brain. In the comparison of different b-values, b2000 was found better among b1000, b2000, and b3000. Conclusion. The rs-DWI offers a useful alternative to routine DWI for detecting the subtle acute infarctions, especially in the regions that are susceptible to distortion as in frontal cortex. In addition, high b-value can also provide benefit by increasing diffusion weighting but further raising can deteriorate image quality as SNR is decreased.

https://ift.tt/2sHC20J

Dynamics and Thermodynamics of Transthyretin Association from Molecular Dynamics Simulations

Molecular dynamics simulations are used in this work to probe the structural stability and the dynamics of engineered mutants of transthyretin (TTR), i.e., the double mutant F87M/L110M (MT-TTR) and the triple mutant F87M/L110M/S117E (3M-TTR), in relation to wild-type. Free energy analysis from end-point simulations and statistical effective energy functions are used to analyze trajectories, revealing that mutations do not have major impact on protein structure but rather on protein association, shifting the equilibria towards dissociated species. The result is confirmed by the analysis of 3M-TTR which shows dissociation within the first 10 ns of the simulation, indicating that contacts are lost at the dimer-dimer interface, whereas dimers (formed by monomers which pair to form two extended -sheets) appear fairly stable. Overall the simulations provide a detailed view of the dynamics and thermodynamics of wild-type and mutant transthyretins and a rationale of the observed effects.

https://ift.tt/2JeNZq9

Atezolizumab for First-Line Treatment of Metastatic Nonsquamous NSCLC

New England Journal of Medicine, Ahead of Print.


https://ift.tt/2Jq61F7

PD-1 Blockade with Cemiplimab in Advanced Cutaneous Squamous-Cell Carcinoma

New England Journal of Medicine, Ahead of Print.


https://ift.tt/2Lp5jFj

Endocrine Adjuvant Therapy for Localized Breast Cancer

New England Journal of Medicine, Ahead of Print.


https://ift.tt/2JtQiVq

Tailoring Adjuvant Endocrine Therapy for Premenopausal Breast Cancer

New England Journal of Medicine, Ahead of Print.


https://ift.tt/2LnmYgK

Atezolizumab for First-Line Treatment of Metastatic Nonsquamous NSCLC

New England Journal of Medicine, Ahead of Print.


https://ift.tt/2Jq61F7