Antisense oligonucleotide (ASO) therapies have been identified as a new treatment modality for intractable diseases. In kidneys treated with ASOs, vacuoles, in addition to basophilic granules, are often observed in the proximal tubules. Some reports have described that these vacuoles are likely to be a secondary phenomenon resulting from the extraction of ASOs during tissue processing. In this study, we compared renal morphology after fixation with Karnovsky’s fixative or 4% paraformaldehyde phosphate buffer (PFA) with that of 10% neutral-buffered formaldehyde solution (NBF). Female Sprague-Dawley rats, intravenously treated four times with 50 mg/kg locked nucleic acid containing antisense oligonucleotides (LNA-ASOs) for 1 or 2 weeks, were examined. Microscopically, vacuoles and basophilic granules in the proximal tubules were observed in the kidneys fixed with NBF. Basophilic granules are indicative of the accumulation of ASOs. Moreover, some of the vacuoles also contained faint basophilic granules, suggesting that the vacuoles were relevant to the accumulation of ASOs. Although moderate vacuolation was observed in the proximal tubules, the majority of the vacuolated epithelia were negative for kidney injury molecule-1 on immunohistochemical staining. Vacuoles in the proximal tubules were not observed in samples subjected to Karnovsky’s fixation, although basophilic granules were observed. In samples subjected to PFA fixation, vacuoles and basophilic granules were observed in the proximal tubules, similar to those in samples subjected to NBF fixation. Overall, our findings demonstrated the possibility of overestimation of vacuolation due to artifacts during tissue processing when using conventional NBF fixation. Karnovsky’s fixative is considered a useful alternative for distinguishing artificial vacuoles from true nephrotoxicity.
In this report, the magnetic dipole moment was used to determine the need for a magnetic shield for capsule endoscopy guiding device. In addition, the index of the number of layers of MSC was examined from the evaluation of the magnetic shield characteristics of the open pail can, which is attracting attention as MSC, and the magnetic dipole moment. As a result, it became clear that the magnetic guiding device needs to be magnetically shielded at 11 Am2 and above. In addition, when the shielding performance of the open pail can was evaluated, it was shown by analysis that the magnetic flux density could be reduced by up to 1.53 mT and the relative permeability was 1000. Finally, it was found that when the magnetic dipole moment of the magnetic inducer is less than 41 Am2, only the open pail can is required, and when it is 41 Am2 or more, the MSC needs to have two or more layers.
In this report, we focus on the magnetic dipole moment and the charge model to model the magnetic shield case of the capsule endoscope guiding device and use the two to propose a cylinder of ϕ100×25 proposed by Matsuhashi. The area where the magnetic flux density distribution is different was clarified. As a result, it was suggested that the charge model is effective near the magnet (l = 0 to 0.3 m) and the magnetic dipole moment is effective far from the magnet (0.4 m ≤ l).
In drug development, assessment of non-clinical peripheral neurotoxicity is important to ensure human safety. Clarifying the pathological features and mechanisms of toxicity enables the management of safety risks in humans by estimating the degree of risk and proposing monitoring strategies. Published guidelines for peripheral neurotoxicity assessment do not provide detailed information on which endpoints should be monitored preferentially and how the results should be integrated and discussed. To identify an optimal assessment method for the characterization of peripheral neurotoxicity, we conducted pathological, biochemical (biomaterials contributing to mechanistic considerations and biomarkers), and behavioral evaluations of isoniazid-treated rats. We found a discrepancy between the days on which marked pathological changes were noted and those on which biochemical and behavioral changes were noted, suggesting the importance of combining these evaluations. Although pathological evaluation is essential for pathological characterization, the results of biochemical and behavioral assessments at the same time points as the pathological evaluation are also important for discussion. In this study, since the measurement of serum neurofilament light chain could detect changes earlier than pathological examination, it could be useful as a biomarker for peripheral neurotoxicity. Moreover, examination of semi-thin specimens and choline acetyltransferase immunostaining were useful for characterizing morphological neurotoxicity, and image analysis of semi-thin specimens enabled us to objectively show the pathological features.
Liquid-liquid phase separation (LLPS) within the cell can form biological condensates, which are increasingly recognized to play important roles in various biological processes. Most proteins involved in LLPS are known to be intrinsically disordered proteins containing intrinsically disordered regions (IDRs) with low complexity regions (LCRs). The proteins driving LLPS were selected from databases of LLPS-related proteins and then classified into three classes according to the components in the condensates. Through in silico analyses, we found that proteins in the homo class, those that induce LLPS without partner molecules, have different IDRs and LCRs compared with the reference proteome. In contrast, proteins in the other classes, those that induce LLPS with partner proteins (the hetero class) or nucleic acids (the mixed class), did not show a clear difference to the reference proteome in IDRs and LCRs. The hetero-class proteins contained structural domains to serve protein-protein interactions, and the mixed-class ones had the structural domains associated with nucleic acids. These results suggest that IDRs in the homo-class proteins have unique IDRs, which provide multivalent interaction sites required for LLPS, whereas the hetero- and mixed-class proteins can induce LLPS through the combination of the interaction among LCRs, structural domains and nucleic acids.
AbstractBackground Intrinsically disordered proteins (IDPs) are proteins that contain intrinsically disordered regions (IDRs), which lack stable three-dimensional structures under physiological conditions. These regions are known to play crucial roles in many biological processes. While IDRs can be predicted from their amino acid sequences, and several accurate IDR prediction programs have been developed, such programs often require substantial computational resources, including long execution time, large databases for homology searches, and advanced computer architectures. Since DNA sequence data continues to grow rapidly, particularly at a genomic scale, there is an increasing need for fast and accurate IDR prediction programs that demand fewer computational resources.Results In this study, we developed DARUMA (Disorder order clAssifier by Rapid and User-friendly MAchine), an IDR prediction program designed for speed and ease of use. DARUMA achieves fast performance by avoiding iterative homology searches while delivering accuracy comparable to the latest predictors that use sequence profiles. In addition to the advantage of execution time, DARUMA requires no additional homology search programs and operates using standard Python libraries, making it easy to install and run on users’ own environments without the need for specialized computational resources.Conclusions DARUMA is a fast, accurate, and user-friendly IDR prediction tool available as both a web interface and a stand-alone distribution at https://antepontem.org/daruma/. Its unique features make it accessible to a wide range of users and a valuable tool for IDR research.
The purpose of this report is to design a magnetic guiding device for guiding capsule endoscopes. The goal is to obtain 17 mT at a distance of 100 mm from the guiding device. Furthermore, the device needs to be lightweight. Two magnetic guiding devices were proposed. The one with 4 magnets arranged was 1475 g, and the one with donut type was 1229 g. In both cases, a magnetic flux density of 17.1 mT was obtained at a distance of 100 mm. However, the magnitude of the magnetic gradient was different, and the magnetic force obtained was 5 mN for the 4 cylindrical magnets and 5.9 mN for the donut type.
