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Background: Diffusion weighted magnetic resonance imaging (DWI) is known to differentiate between malignant and benign lesions via the apparent diffusion coefficient (ADC). Here, the value of diffusion kurtosis imaging (DKI) for differentiation and further characterization of benign and malignant breast lesions and their subtypes in a clinically feasible protocol is investigated., Material and Methods: This study included 85 patients (with 68 malignant and 73 benign lesions) who underwent 3 T breast DWI using three b values (50, 750, 1500 s/mm 2 ), with a total measurement time < 5 min. ADC maps were calculated from b values 50, 750 s/mm 2 . The diffusion kurtosis model was fitted to the diffusion weighted images, yielding in each lesion the average kurtosis-corrected diffusion coefficient D K and mean kurtosis K. Histopathology was obtained of radiologically suspicious lesions; follow-up scans were used as a standard of reference for benign appearing lesions. Receiver operating characteristic curves were used to evaluate the parameters' diagnostic performance for differentiation of lesion types and grades. The difference in diffusion parameters between subgroups was analysed statistically using the Wilcoxon rank sum test and Kruskal-Wallis test, applying a Bonferroni correction for multiple testing where necessary., Results: ADC, D K and K showed significant differences between malignant and benign lesions (p < 10 -5 ). All parameters had similar areas under the curve (AUC) (ADC: 0.92, D K : 0.91, K: 0.89) for differentiation of malignant and benign lesions. Sensitivity was highest for ADC (ADC: 0.96, D K : 0.94, K: 0.93), as well as specificity (ADC: 0.85, D K : 0.82, K: 0.82). ADC and D K showed significant differences between tumor histologic grades (p = 6.8⋅10 -4 , p = 6.6 · 10 -5 , respectively), whereas K did not (p = 0.99). All three parameters differed significantly between subtypes of benign lesions (ADC: p < 10 -5 , D K : p< 10 -5 , K: p = 4.1·10 -4 ), but not between subtypes of malignant lesions (ADC: p = 0.21, D K : p = 0.25, K: p = 0.08)., Conclusion: DKI parameters and conventional ADC can differentiate between malignant and benign lesions. Differentiation performance was best for ADC. Different tumor grades were significantly different in ADC and D K , which may have an impact on therapy planning and monitoring. In our study, K did not add value to the diagnostic performance of DWI in a clinical setting., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Zebrafish primordial germ cells (PGCs) constitute a useful in vivo model to study cell migration and to elucidate the role of specific proteins in this process. Here we report on the role of the heat shock protein Hsp90aa1.2, a protein whose RNA level is elevated in the PGCs during their migration. Reducing Hsp90aa1.2 activity slows down the progression through the cell cycle and leads to defects in the control over the MTOC number in the migrating cells. These defects result in a slower migration rate and compromise the arrival of PGCs at their target, the region where the gonad develops. Our results emphasize the importance of ensuring rapid progression through the cell cycle during single-cell migration and highlight the role of heat shock proteins in the process., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Solution pH and ionic strength (I) have complex effects on protein stability. We developed an experimental approach based on exploitation of the zwitterionic characteristic of amino acid molecules to probe the relative contribution from each. A variety of types of amino acid solutions were adopted to investigate the effects of pH and I in a manner that allows independent evaluation of each factor. The same effect could not be achieved using conventional buffer solutions. Size-exclusion chromatography, capillary differential scanning calorimetry, and fluorescence spectroscopy were utilized to probe the protein aggregation and conformation. The results suggested that, in addition to pH, solution ionic strength as a function of ionization state of the amino acid molecules and the ions introduced by pH adjustment played an important role in the aggregation and conformation of the protein studied. This experimental approach offers a useful tool to aid fundamental understanding of the relative effects of solution pH and ionic strength on protein stability., (© 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.)

Tropomyosin is an alpha-helical coiled-coil protein that aligns head-to-tail along the length of the actin filament and regulates its function. The solution structure of the functionally important N terminus of a short 247-residue non-muscle tropomyosin was determined in an engineered chimeric protein, GlyTM1bZip, consisting of the first 19 residues of rat short alpha-tropomyosin and the last 18 residues of the GCN4 leucine zipper. A gene encoding GlyTM1bZip was synthesized, cloned and expressed in Escherichia coli. Triple resonance NMR spectra were analyzed with the program AutoAssign to assign its backbone resonances. Multidimensional nuclear Overhauser effect spectra, X-filtered spectra and (3)J(H(N)-H(alpha)) scalar coupling were analyzed using AutoStructure. This is the first application of this new program to determine the three-dimensional structure of a symmetric homodimer and a structure not previously reported. Residues 7-35 in GlyTM1bZip form a coiled coil, but neither end is helical. Heteronuclear (15)N-(1)H nuclear Overhauser effect data showed that the non-helical N-terminal residues are flexible. The (13)C' chemical shifts of the coiled-coil backbone carbonyl groups in GlyTM1bZip showed a previously unreported periodicity, where resonances arising from residues at the coiled-coil interface in a and d positions of the heptad repeat were displaced relatively upfield and those arising from residues in c positions were displaced relatively downfield. Heteronuclear single quantum coherence spectra, collected as a function of temperature, showed that cross-peaks arising from the alpha-helical backbone and side-chains at the coiled-coil interface broadened or shifted with T(M) values approximately 20 degrees C lower than the loss of alpha-helix measured by circular dichroism, suggesting the presence of a folding intermediate. The side-chain of Ile14, a residue essential for binding interactions, exhibited multiple conformations. The conformational flexibility of the N termini of short tropomyosins may be important for their binding specificity., (Copyright 2001 Academic Press.)

The purpose of the study was to explore the relationship between social interaction and cardiovascular activity during a conflict-inducing communication task in Type A and B subjects. One of the subjects, the leader, was instructed to lead the other subject, the follower, through defined routes on a city map merely by help of instructions. The subjects were facing each other on each side of a screen which allowed eye contact but shielded the maps from view. 40 male students (mean age 24 years) exhibiting Type A or Type B behavior according to the Videotaped Structured Interview participated in the study. The results demonstrated large cardiovascular increases during task performance, particularly for leaders, in systolic blood pressure and heart rate. There were no main effects of Type A vs. Type B, but dyads composed of two Type As showed larger increase in diastolic blood pressure during the conflict phase of the task compared to dyads composed of Type Bs.

The effects of cannulation of the radial artery were studied in 23 patients. Distal arterial pressure on the thumb, measured during radial or ulnar artery compression, was compared with the result of a modified Allen test performed before operation. Distal arterial pressure on the thumb was monitored for approximately 10 days after removal of the cannula. It was found that radial artery thrombosis, as defined by a thumb arterial pressure of less than 10 mm Hg during ulnar artery compression, occurred with a frequency of about 40% depending on the duration of cannulation. Furthermore, thrombosis of the radial artery resulted in a decrease in perfusion pressure in the thumb of from 17 to 33% of the values before cannulation. However, a satisfactory result from a carefully performed Allen test seems to ensure that post-thrombotic perfusion pressure in the thumb is not decreased to values associated with compromised nutrition of the tissues.

Strain-gauge plethysmography was used to determine the systolic arterial pressure in the great toe of 38 patients (aged 23-70 yr) undergoing lung surgery. In eight patients (21%) manual compression of the dorsalis pedis artery reduced the arterial pressure in the great toe to less than 40 mm Hg, and cannulation of the artery was not attempted. In 24 of 30 patients with adequate collateral arterial supply, a Teflon cannula (Venflon 1.20) was inserted percutaneously to the dorsalis pedis artery. Median cannulation time was 160 min. Six patients (25%, 95% confidence limits 10-47%) developed thrombosis of the artery and, in one, unsuccessful cannulation caused thrombosis. In two patients, recanalization of the artery occurred between the 2nd and the 8th day after operation. In four patients, examination 3-5 months after cannulation revealed a persisting decrease in the function of the dorsalis pedis artery. This suggests that the dorsalis pedis artery should not normally be selected for cannulation.

Arterial pressure was measured simultaneously in the thumb and in the contralateral arm using strain-gauge plethysmography in 100 healthy persons aged 13--43 yr, before and after compression of the radial or the ulnar artery. The radial and ulnar pulses were palpable in all instances. In 29 (14.5%) hands compression of either artery did not reduce the thumb pressure. In 152 (76%) occlusion of the radial artery caused a decrease of more than 10 mm Hg, but never to less than 40 mm Hg. In 91 (45.5%) occlusion of the ulnar artery reduced thumb pressure, on three occasions to less than 40 mm Hg. Radial dominance was shown in 110 hands (55.0%), 24 (12.0%) showed ulnar dominance and in 66 (33.0%) neither vessel dominated.