Alcohols denature the native state of proteins, and also stabilize the α‐helical conformation in unfolded proteins and peptides. Among various alcohols, trifluoroethanol (TFE) and ...hexafluoroisopropanol (HFIP) are often used because of their high potential to induce such effects. However, the reason why TFE and HFIP are more effective than other alcohols is unknown. Using CD, we studied the effects of TFE and HFIP as well as reference alcohols, i.e., methanol, ethanol, and isopropanol, on the conformation of bovine β‐lactoglobulin and the bee venom melittin at pH 2. Upon addition of alcohols, β‐lactoglobulin exhibited a transformation from the native state, consisting of β‐sheets, to the α‐helical state, whereas melittin folded from the unfolded state to the α‐helical state. In both cases, the order of effectiveness of alcohols was shown to be: HFIP > TFE > isopropanol > ethanol > methanol. The alcohol‐induced transitions were analyzed assuming a two‐state mechanism to obtain the m value, a measure of the dependence of the free energy change on alcohol concentration. Comparison of the m values indicates that the high potential of TFE can be explained by the additive contribution of constituent groups, i.e., F atoms and alkyl group. On the other hand, the high potential of HFIP is more than that expected from the additive effects, suggesting that the cooperative formation of micelle‐like clusters of HFIP is important.
The separation of biological materials by the magneto-Archimedes levitation technique is discussed in the present paper. Magneto-Archimedes levitation is a useful technique to levitate feeble ...magnetic materials by superconducting magnets of the 10 T class. Since the stable levitation position of matter is decided by the volume magnetic susceptibilities and densities of the object and the surrounding media, by utilizing the magneto-Archimedes levitation technique, a mixture of several materials can be spatially separated into each component. In a biological system, there are many materials with quite similar compositions or conformations. Even though the differences in their compositions or conformations are trivial, they may result in differences in their magnetic properties. Using magneto-Archimedes levitation, it seems possible to realize the fine separation of biological materials that have quite similar structures. The possibility of this novel fine separation technique for biological materials was evaluated using collagens as an example of a system with similar structures.
As a new approach to predicting
in vivo drug metabolism in humans, scaling of
in vivo metabolic clearance from
in vitro data obtained using human liver microsomes or hepatocytes is described in this ...review, based on the large number of literature data. Successful predictions were obtained for verapamil, loxtidine (lavoltidine), diazepam, lidocaine, phenacetin and some other compounds where CL
int,
in vitro
is comparable with CL
int,
in vivo
. On the other hand, for some metabolic reactions, differences in CL
int,
in vitro
and CL
int,
in vivo
greater than 5-fold were observed. The following factors are considered to be the cause of the differences: (1) metabolism in tissues other than liver, (2) incorrect assumption of rapid equilibrium of drugs between blood and hepatocytes, (3) presence of active transport through the sinusoidal membrane, and (4) interindividual variability. Furthermore, the possibility of predicting
in vivo drug metabolic clearance from results obtained using a recombinant system of human P450 isozyme was described for a model compound, YM796, where the predicted metabolic clearances obtained from the recombinant system, taking account of the content of the P450 isozyme CYP3A4 in the human microsomes, were comparable with the observed clearances using human liver microsomes containing different amounts of CYP3A4. Even in the case where the first-pass metabolism exhibits nonlinearity, it appears to be possible to predict
in vivo metabolic clearance from
in vitro metabolic data.
The sixth version of the Model for Interdisciplinary Research on Climate
(MIROC), called MIROC6, was cooperatively developed by a Japanese modeling
community. In the present paper, simulated mean ...climate, internal
climate variability, and climate sensitivity in MIROC6 are evaluated and
briefly summarized in comparison with the previous version of our climate
model (MIROC5) and observations. The results show that the overall
reproducibility of mean climate and internal climate variability in MIROC6
is better than that in MIROC5. The tropical climate systems (e.g.,
summertime precipitation in the western Pacific and the eastward-propagating
Madden–Julian oscillation) and the midlatitude atmospheric circulation
(e.g., the westerlies, the polar night jet, and troposphere–stratosphere
interactions) are significantly improved in MIROC6. These improvements can
be attributed to the newly implemented parameterization for shallow
convective processes and to the inclusion of the stratosphere. While there
are significant differences in climates and variabilities between the two
models, the effective climate sensitivity of 2.6 K remains the same because
the differences in radiative forcing and climate feedback tend to offset
each other. With an aim towards contributing to the sixth phase of the
Coupled Model Intercomparison Project, designated simulations tackling a
wide range of climate science issues, as well as seasonal to decadal climate
predictions and future climate projections, are currently ongoing using
MIROC6.
We are developing a superconducting magnet system that can, on the ground, control gravitational force on protein crystal solutions through use of magnetic forces. Magnetic forces give rise to a ...variety of effects on motions of protein solutions. We proposed a dynamical model of fluid and material flow in solution under gravity and magnetic force in our previous works. The numerical calculation results showed that magnetic forces could suppress convections and lead to unexpected concentration distributions of solutes under some hypothetical conditions. In this paper, we present some simulation results under actual conditions in a superconducting magnet. The results show that inhomogeneity of magnetic force affects modifies concentration and convection distributions.
We examined the malting and brewing performances of a lipoxygenase-1 (LOX-1) null line of barley (Hordeum vulgare L.). The LOX-normal malt and the LOX-null malt were prepared from F4 populations ...derived from a single cross. We could not observe any major differences in the general malt characteristics between the two malts. A brewing trial was performed using these malts. The analysis of the wort and beer revealed that the absence of LOX-1 had little effect on the general characteristics of the wort and beer. In contrast, beer made from the LOX-null malt showed reduced levels of beer-deteriorating substances, trans-2-nonenal (T2N), and trihydroxyoctadecenoic acid (THOD). In the sensory evaluation, well-trained panel members recognized the significant superiority of the aged LOX-null beer in terms of staleness. These results show that the LOX-1 null barley line can be effectively used to improve the flavor stability of beer without changing the other important beer qualities.
Abstract
Background
Radiomics is a comprehensive analysis methodology of medical image and involves the extraction of numerous features from standard imaging. Its usefulness has been reported mainly ...in the field of cancer for diagnosis and prediction of prognosis. In the territory of cardiac imaging, several reports have investigated the utility of radiomics for classifying the risk of prognosis in coronary artery disease, and few practical applications have been reported for patients with atrial fibrillation (AF) who underwent pulmonary vein isolation (PVI). Although the left atrial morphology can affect the clinical course after the PVI procedure, it is unclear whether the radiomics feature values of the left atrial morphology on cardiac computed tomography (CT) is useful for predicting the AF recurrence after PVI.
Purpose
To predict the recurrence of AF after PVI using the radiomics feature values of the left atrial morphology on cardiac computed tomography (CT).
Methods
We analyzed 525 consecutive three-dimensional cardiac CT in patients with atrial fibrillation who underwent PVI from 2018 to 2019 in our institute. After marking the region of interest on left atrium (including the root of pulmonary veins) semiautomatically, 107 radiomics feature values were obtained by Python program. After excluding the parameters having collinearity or with low predictive capability for the recurrence of AF after PVI, 42 parameters were applied to the final prediction model. Two prediction models were constructed by multivariate Cox regression analysis and machine learning model by support vector machine algorithm.
Results
The area under the curve (AUC) for predicting the recurrence of AF was 0.815 for the multivariate Cox regression model and 0.826 for the machine learning model by support vector machine.
Conclusion
The radiomics feature values on preprocedural cardiac CT could be helpful for predicting the recurrence of AF after PVI. Since radiomics feature analysis yields a huge number of numerical values representing the left atrial morphology in a reproducible manner, it would provide a new direction to construct a good prediction model using machine learning including artificial intelligence out of a routine cardiac CT scan.
Funding Acknowledgement
Type of funding sources: None.
PDF
