Search

Only graminaceous monocots possess the Strategy II iron (Fe)-uptake system in which Fe is absorbed by roots as an Fe3+-phytosiderophore. In spite of being a Strategy II plant, however, rice ( Oryza sativa) contains the previously identified Fe2+ transporter OsIRT1 . In this study, we isolated the OsIRT2 gene from rice, which is highly homologous to OsIRT1. Real-time PCR analysis revealed that OsIRT1 and OsIRT2 are expressed predominantly in roots, and these transporters are induced by low-Fe conditions. When expressed in yeast ( Saccharomyces cerevisiae) cells, OsIRT2 cDNA reversed the growth defects of a yeast Fe-uptake mutant. This was similar to the effect of OsIRT1 cDNA. OsIRT1– and OsIRT2–green fluorescent protein fusion proteins localized to the plasma membrane when transiently expressed in onion ( Allium cepa L.) epidermal cells. OsIRT1 promoter– GUS analysis revealed that OsIRT1 is expressed in the epidermis and exodermis of the elongating zone and in the inner layer of the cortex of the mature zone of Fe-deficient roots. OsIRT1 expression was also detected in the ccompanion cells. Analysis using the positron-emitting tracer imaging system showed that rice plants are able to take up both an Fe3+-phytosiderophore and Fe2+. This result indicates that, in addition to absorbing an Fe3+-phytosiderophore, rice possesses a novel Fe-uptake system that directly absorbs the Fe2+, a strategy that is advantageous for growth in submerged conditions. [ABSTRACT FROM AUTHOR]

Three thienopyrrole-fused thiadiazole (TPT) fluorescent dyes featuring a common amide linker and different alkoxy substituents on peripheral trialkoxybenzene moieties were synthesized, and their self-assembly behavior in solution was investigated. The obtained results revealed a substantial steric effect of the alkoxy substituents on the supramolecular polymerization mechanism, which results from a combination of π-stacking and hydrogen (H)-bonding interactions. Detailed spectroscopic measurements revealed that with increasing steric demand of the substituents, the supramolecular polymerization processes in pure methylcyclohexane (MCH) or a mixture of MCH and toluene become temperature-sensitive and enthalpically favorable, resulting in a change from the isodesmic assembly mechanism to the cooperative mechanism. Theoretical calculations suggested that in TPTs with bulky substituents, steric hindrance causes the H-bonding array of the amide moieties to be aligned along the stacking axis of the π-systems; thus, the H-bonding interactions are strengthened compared to those in TPTs with less bulky substituents, compensating for the weakened π-stacking interactions. A chiral TPT derivative with (S) stereogenic centers was found to form homochiral helical supramolecular assemblies that generate discernible circularly polarized luminescence. Achiral TPTs also generate helical assemblies to which preferential helicity can be imparted through the external chiral bias of the solvents (R)- and (S)-limonene., (© 2024 Wiley‐VCH GmbH.)

Murine IL-17-producing γδT (γδT17) cells are divided into two subsets: natural γδT17 (nγδT17) cells, whose development is restricted to the fetal thymus, and inducible γδT17 cells, which require antigen exposure for their IL-17 production and are presumed to develop from Rorc + Il17a - CCR9 + immature γδT17 cells in the adult thymus and whose T cell receptor (TCR) is biased toward Vγ4. Although IL-23 is known to be involved in developing γδT17 cells, the roles of other cytokines, such as IL-21, which is involved in developing Th17 cells like IL-23, in the development, maintenance, and pathophysiology of γδT17 cells remain unknown. Here, we show that IL-21 is dispensable for the fetal thymic development of nγδT17 cells but is required for the peripheral maintenance of Vγ4 + nγδT17 cells. Upon stimulation with γδTCR, IL-1 plus IL-21 induces the proliferation of Vγ4 + nγδT17 cells via STAT3 as effectively as IL-1 plus IL-23. Using bone marrow chimeric mice, we demonstrated that immature γδT17 cells are produced de novo in the adult mice from donor adult bone marrow cells and that IL-21 is dispensable for their development. Instead, IL-21 is required to expand newly induced Vγ4 + γδT17 cells in the periphery upon immunization. Finally, using adoptive transfer experiments of γδT17 cells, we found that IL-21 receptors on γδT17 cells are involved in maintaining Vγ4 + γδT17 cells, subsequent infiltration of Th17 cells into the spinal cord, and exacerbation of experimental autoimmune encephalomyelitis. Collectively, IL-21 plays a vital role in the maintenance and pathogenesis of Vγ4 + γδT17 cells., Competing Interests: The authors declare that the research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Ishikawa, Suto, Abe, Hayashi, Suga, Tanaka, Kageyama, Iwata, Suzuki, Suzuki and Nakajima.)

During the self-assembly of π-conjugated molecules, linkers and substituents can potentially add supportive noncovalent intermolecular interactions to π-stacking interactions. Here, we report the self-assembly behavior of thienopyrrole-fused thiadiazole (TPT) fluorescent dyes that possess ester or ether linkers and dodecyloxy side chains in solution and the condensed phase. A comparison of the self-association behavior of the ester- and ether-bridged compounds in solution using detailed UV-vis, fluorescence, and NMR spectroscopic studies revealed that the subtle replacement of the ether linkers by ester linkers leads to a distinct increase in the association constant (ca. 3-4 fold) and the enthalpic contribution (ca. 3 kcal mol -1 ). Theoretical calculations suggest that the ester linkers, which are in close proximity to one another due to the π-stacking interactions, induce attractive electrostatic forces and augment self-association. The self-assembly of TPT dyes into well-defined 1D clusters with high aspect ratios was observed, and their morphologies and crystallinity were investigated using SEM and X-ray diffraction analyses. TPTs with ester linkers exhibit a columnar liquid crystalline mesophase in the condensed phase., (© 2021 Wiley-VCH GmbH.)

Stimuli-response on hierarchically-structured surface wrinkles is required for advanced filtration, catalysis and sensing applications. Although conventional processes can form hierarchical surface wrinkles, incorporation of stimuli-responsive features has not been achieved, limiting the potential multi-scale functionality of wrinkles. Here, we demonstrate a novel process that can fabricate stimuli-responsive surface hierarchical structures on silica-polymer hybrid films through precisely controlled UV-polymerization and sol-gel condensation. Starting from uniform hybrid films, UV excitation of the film surface triggers the formation of micrometre-scale wrinkles with dual periodicity. Hierarchical nested wrinkle (NW) structures with controllable periodic lengths at discrete size scales of < 10 µm and > 23 µm show a shape-memory effect with changes in the surrounding humidity. Moreover, the individual responses of wrinkles with different periodicities can be controlled independently. As a proof-of-concept application, we demonstrate that the NW structures are an active size-selective adsorption/release surface for micrometre-sized particles.

Background: Electroconvulsive therapy (ECT) is reported to be effective for intractable chronic pain with depression. However, not much has been done to clarify the ECT target in patients, whether the pain or the depression. We report a case of intractable chronic regional pain syndrome (CRPS) with secondary depression in which the depression was treated successfully with an initial acute ECT course, and the pain finally improved with two additional ECT courses., Case Reports: The patient was a 48-year-old woman with CRPS and depression caused by failed back syndrome. The CRPS with depression did not respond to standard treatments. A course of bilateral acute ECT (12 sessions) improved the depressive symptoms but not the pain. The depression relapsed 1 month after the response to ECT. A second course of acute ECT (20 sessions) followed by continuation ECT (11 sessions) improved the depression but not the pain. The depression recurred 1 year after the response to acute ECT. A third course of acute ECT (12 sessions) finally improved the pain and resolved the depression., Conclusions: Our experience in thin case suggests that the therapeutic target in patients with chronic organic pain and secondary depression should be the pain; repeated ECT courses are likely to be effective for the pain, although the depression may resolve first.

The authors have previously studied the short-term effect of the first acute electroconvulsive therapy (ECT) course (phase 1 study) on intractable catatonic schizophrenia and the 1-year relapse rate after response to the acute ECT (phase 2 study) in middle-aged and elderly patients. Results indicated that, although acute ECT has an excellent short-term effect, the 1-year relapse rate after response to acute ECT is high despite the use of continuation neuroleptics. In the present prospective study the effect was explored of continuation ECT with neuroleptics on the prevention of relapse after response to a second acute ECT course in the relapsed participants of the phase 2 study. The present study included seven consecutive patients > 45 years of age with catatonic schizophrenia (Diagnostic and Statistical Manual of Mental Disorders (4th edn; DSM-IV) who relapsed (despite the use of neuroleptics) within 1 year after response to the first acute ECT course, and then responded to the second acute ECT course. The patients were given continuation ECT combined with neuroleptics; four ECT sessions at weekly intervals, then four ECT sessions every 2 weeks, then three ECT sessions every 4 weeks. Clinical symptoms were evaluated by means of the Brief Psychiatric Rating Scale (BPRS) weekly for 48 weeks or until relapse. Relapse was defined as a BPRS score of at least 37 for 3 consecutive days. Three out of the seven patients (42.9%) had a sustained response to ECT during the 1-year follow-up period. In the seven patients the probability of relapse within 1 year under treatment with neuroleptics alone (phase 2 study) was statistically higher than that under continuation ECT combined with neuroleptics (present study). No statistical differences were seen between the phase 2 study and the present study in the severity of psychiatric symptoms, global social function, the number of acute ECT sessions or the dosage of neuroleptics. No patient experienced a severe cognitive or physical adverse effect resulting from continuation ECT. Continuation ECT with neuroleptics is an efficacious and safe treatment for maintaining a response in middle-aged and elderly patients with intractable catatonic schizophrenia who have relapsed after a positive response to acute ECT despite the use of continuation neuroleptics.

The impact of electroconvulsive therapy (ECT) on the regional cerebral blood flow (rCBF) abnormalities in late-life depression is still unknown and the clinical significance of these findings in late-life depression has not been fully discussed. Using single photon emission computed tomography (SPECT) with 99mTc-hexamethylpropylene amine oxime (99mTc-HMPAO), we examined the changes of rCBF patterns in nine late-life patients with major depressive episodes before and following response to ECT compared with nine age- and sex-matched healthy volunteers. Statistical comparisons were made on both region-of-interest (ROI) and voxel-by-voxel bases. In ROI-based analyses, a mean rCBF was significantly decreased in the patients before ECT compared with the control, significantly increased (normalized) in the patients 2 weeks after ECT compared with that before ECT, and still increased in the patients 12 weeks after ECT compared with that before ECT. In voxel-by-voxel analyses, a significant rCBF reduction was found in the bilateral pre- and subcallosal anterior cingulate cortex, the bilateral caudal orbitofrontal cortex, the right insular cortex and the right posterior middle frontal gyrus in patients before ECT compared with the control, and similar rCBF patterns were shown at 2 weeks and 12 weeks after ECT. We propose the hypothesis that a mean rCBF reduction may have a state-related property while persistent anterior paralimbic hypoperfusion may have a trait-like property, which relates to the relapse vulnerability as well as a tendency toward medication failure and illness chronicity in late-life depression.