Amstrupfitzpatrick9536
At each inversion's optimal kernel size in simulation (7 × 7 × 7 for HLI, 11 × 11 × 11 for ILI), ILI is more sensitive to true changes in stiffness in gray-matter regions of interest in simulation. In vivo, there is no difference in the region-level repeatability of stiffness estimates between the inversions, although ILI appears to better maintain the stiffness map structure as kernel size increases, while decreasing the spatial variance in stiffness estimates.
This study suggests that inhomogeneous inversions provide small but significant benefits even when large stiffness gradients are absent.
This study suggests that inhomogeneous inversions provide small but significant benefits even when large stiffness gradients are absent.Metastasis is the main cause of cancer patients' death despite tremendous efforts invested in developing the related molecular mechanisms. During cancer cell migration, cells undergo dynamic regulation of filopodia, focal adhesion, and endosome trafficking. Cdc42 is imperative for maintaining cell morphology and filopodia, regulating cell movement. Integrin beta1 activates on the endosome, the majority of which distributes itself on the plasma membrane, indicating that endocytic trafficking is essential for this activity. In cancers, high expression of lysosome-associated protein transmembrane 4B (LAPTM4B) is associated with poor prognosis. LAPTM4B-35 has been reported as displaying plasma membrane distribution and being associated with cancer cell migration. However, the detailed mechanism of its isoform-specific distribution and whether it relates to cell migration remain unknown. Here, we first report and quantify the filopodia localization of LAPTM4B-35 mechanically, that specific interaction with Cdc42 promoted its localization to the filopodia. Furthermore, our data show that LAPTM4B-35 stabilized filopodia and regulated integrin beta1 recycling via interaction and cotrafficking on the endosome. In our zebrafish xenograft model, LAPTM4B-35 stimulated the formation and dynamics of focal adhesion, further promoting cancer cell dissemination, whereas in skin cancer patients, LAPTM4B level correlated with poor prognosis. In short, this study establishes an insight into the mechanism of LAPTM4B-35 filopodia distribution, as well as into its biological effects and its clinical significance, providing a novel target for cancer therapeutics development.Understanding why some wounds are hard to heal is important for improving care and developing more effective treatments. The method of sample collection used is an integral step in the research process and thus may affect the results obtained. The primary objective of this study was to summarise and map the methods currently used to sample wound fluid for protein profiling and analysis. Eligible studies were those that used a sampling method to collect wound fluid from any human wound for analysis of proteins. A search for eligible studies was performed using MEDLINE, Embase and CINAHL Plus in May 2020. All references were screened for eligibility by one reviewer, followed by discussion and consensus with a second reviewer. Quantitative data were mapped and visualised using appropriate software and summarised via a narrative summary. After screening, 280 studies were included in this review. The most commonly used group of wound fluid collection methods were vacuum, drainage or use of other external devices, with surgical wounds being the most common sample source. Other frequently used collection methods were extraction from absorbent materials, collection beneath an occlusive dressing and direct collection of wound fluid. This scoping review highlights the variety of methods used for wound fluid collection. Many studies had small sample sizes and short sample collection periods; these weaknesses have hampered the discovery and validation of novel biomarkers. Future research should aim to assess the reproducibility and feasibility of sampling and analytical methods for use in larger longitudinal studies.
To evaluate the ability of the PRESS sequence (T
=97 ms, optimized for 2-hydroxyglutarate detection) to detect cystathionine in gliomas and the effect of the omission of cystathionine on the quantification of the full neurochemical profile.
Twenty-three subjects with a glioma were retrospectively included based on the availability of both MEGA-PRESS and PRESS acquisitions at 3T, and the presence of the cystathionine signal in the edited MR spectrum. In eight subjects, the PRESS acquisition was performed also in normal tissue. Metabolite quantification was performed using LCModel and simulated basis sets. The LCModel analysis for the PRESS data was performed with and without cystathionine.
All subjects with glioma had detectable cystathionine levels >1 mM with Cramér-Rao lower bounds (CRLB) <15%. The mean cystathionine concentrations were 3.49 ± 1.17 mM for MEGA-PRESS and 2.20 ± 0.80 mM for PRESS data. Cystathionine concentrations showed a significant correlation between the two MRS methods (r=0.58, p=.004), and it was not detectable in normal tissue. Using PRESS, 19 metabolites were quantified with CRLB <50% for more than half of the subjects. Selleckchem AG 825 The metabolites that were significantly (p < .0028) and mostly affected by the omission of cystathionine were aspartate, betaine, citrate, γ-aminobutyric acid (GABA), and serine.
Cystathionine was detectable by PRESS in all the selected gliomas, while it was not detectable in normal tissue. The omission from the spectral analysis of cystathionine led to severe biases in the quantification of other neurochemicals that may play key roles in cancer metabolism.
Cystathionine was detectable by PRESS in all the selected gliomas, while it was not detectable in normal tissue. The omission from the spectral analysis of cystathionine led to severe biases in the quantification of other neurochemicals that may play key roles in cancer metabolism.
To develop a convolutional neural network (CNN) for the robust and fast correction of velocity aliasing in 4D-flow MRI.
This study included 667 adult subjects with aortic 4D-flow MRI data with existing velocity aliasing (n= 362) and no velocity aliasing (n= 305). Additionally, 10 controls received back-to-back 4D-flow scans with systemically varied velocity-encoding sensitivity (vencs) at 60, 100, and 175 cm/s. The no-aliasing data sets were used to simulate velocity aliasing by reducing the venc to 40%-70% of the original, alongside a ground truth locating all aliased voxels (153 training, 152 testing). The 152 simulated and 362 existing aliasing data sets were used for testing and compared with a conventional velocity antialiasing algorithm. Dice scores were calculated to quantify CNN performance. For controls, the venc 175-cm/s scans were used as the ground truth and compared with the CNN-corrected venc 60 and 100 cm/s data sets RESULTS The CNN required 176 ± 30 s to perform compared with 162 ± 14 s for the conventional algorithm. The CNN showed excellent performance for the simulated data compared with the conventional algorithm (median range of Dice scores CNN [0.89-0.99], conventional algorithm [0.84-0.94], p< 0.001, across all simulated vencs) and detected more aliased voxels in existing velocity aliasing data sets (median detected CNN 159 voxels [31-605], conventional algorithm 65 [7-417], p< 0.001). For controls, the CNN showed Dice scores of 0.98 [0.95-0.99] and 0.96 [0.87-0.99] for venc=60 cm/s and 100 cm/s, respectively, while flow comparisons showed moderate-excellent agreement.
Deep learning enabled fast and robust velocity anti-aliasing in 4D-flow MRI.
Deep learning enabled fast and robust velocity anti-aliasing in 4D-flow MRI.
The traditional radiofrequency (RF)-prepared B
mapping technique consists of one scan with an RF preparation module for flip angle-encoding and a second scan without this module for normalizing. To reduce the T
-induced k-space filtering effect, this method is limited to 2D FLASH acquisition with a two-parameter method. A novel 3D RF-prepared three-parameter method for ultrafast B
-mapping is proposed to correct the T
-induced quantification bias.
The point spread function analysis of FLASH shows that the prepared longitudinal magnetization before the FLASH acquisition and the image signal obeys a linear (not proportional) relationship. The intercept of the linear function causes the quantification bias and can be captured by a third saturated scan.
Using the 2D double-angle method (DAM) as the reference, a 3D RF-prepared three-parameter protocol with 9 s duration was compared with the two-parameter method, as well as the saturated DAM (SDAM) method, the dual refocusing echo acquisition mode (DREAM) method, and the actual flip-angle imaging (AFI) method, for B
mapping of brain, breast, and abdomen with different orientations and shim settings at 3T.
The 3D RF-prepared three-parameter method with complex-subtraction delivered consistently lower RMS error, error mean, error standard deviation, and higher concordance correlation coefficients values than the two-parameter method, the three-parameter method with magnitude-subtraction, the multi-slice DREAM and the 3D AFI, and were close to the results of 2D or multi-slice SDAM.
The proposed ultrafast 3D RF-prepared three-parameter method with complex-subtraction was demonstrated with high accuracy for B
mapping of brain, breast, and abdomen.
The proposed ultrafast 3D RF-prepared three-parameter method with complex-subtraction was demonstrated with high accuracy for B1 mapping of brain, breast, and abdomen.Understanding how plants adjust their requirements for different N forms can help elucidate plant coexistence strategies in N-limited desert ecosystems. To understand the mechanisms involved, we investigated whether two desert herbs can directly absorb dissolved organic nitrogen (N) and tested whether the patterns changed over different growth stages. Two dominant herbaceous species, Astragalus arpilobus and Arnebia decumbens, from the southern edge of the Gurbantunggut desert, China, were selected. Short-term (24 h) 15 N-labelled tracer (15 N-NO3 , 15 N-NH4 , 2-13 C-15 N-Glycine) treatments were conducted at two soil depths (0-5 cm and 5-15 cm) in the season of rapid growth (June) and in the peak biomass season (July). Enrichment in 13 C and 15 N was assessed in the two species receiving glycine. The ratio 13 C15 N was 0.21-1.39 at the 24-h harvest, suggesting that approximately 10.5-69.5% of glycine had been absorbed. The amount of absorbed 15 N was significantly affected by species, month, soil depth and N form. The two species absorbed most 15 N from the 0-5 cm soil layer, and the absorption rate in July was higher than that in June. The absorption of 15 N-NO3 and 15 N-NH4 was significantly higher than that of 2-13 C-15 N-Glycine. The results indicate that these herbs could use amino acids in the N-deficient desert ecosystem. The two co-existing species used different forms of inorganic N for their requirements and maintained a specific preference throughout various growth stages.
The non-invasive determination of the free magnesium ion concentration ([Mg
]) using
P MRSI in vivo is of interest in research on various pathologies, e.g. diabetes. The purpose of this study was to demonstrate the potential of
P MRSI at 7 T to enable volumetric, high-resolution mapping of [Mg
].
3D
P MRSI datasets from the lower leg of three healthy volunteers were acquired at B
= 7 T with a nominal spatial resolution of (8× 8× 16)mm
in 56 min. Volumetric [Mg
] maps were calculated based on the quantified local chemical shift difference between the α- and β-resonance of adenosine triphosphate (ATP) considering also local pH values. Mean [Mg
] values from three different muscle groups were compared. To demonstrate the potential of reducing the measurement time, the analysis was repeated on the acquired MRSI data retrospectively reconstructed with fewer averages.
The generated [Mg
] maps revealed local differences, and mean [Mg
] values of (1.08 ± 0.03)mM were found in the tibialis anterior, (0.