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The thylakoid membrane remodeling protein VIPP1 forms bundled oligomers in tobacco chloroplasts
Full text linkThe thylakoid membrane (TM) serves as the scaffold for oxygen-evolving photosynthesis, hosting the protein complexes responsible for the light reactions and ATP synthesis. Vesicle inducing protein in plastid 1 (VIPP1), a key protein in TM remodeling, has been recognized as essential for TM homeostasis. In vitro studies of cyanobacterial VIPP1 demonstrated its ability to form large homo-oligomers (2 MDa) manifesting as ring-like or filament-like assemblies associated with membranes. Similarly, VIPP1 in Chlamydomonas reinhardtii assembles into rods that encapsulate liposomes or into stacked spiral structures. However, the nature of VIPP1 assemblies in chloroplasts, particularly in Arabidopsis, remains uncharacterized. Here, we expressed Arabidopsis thaliana VIPP1 fused to GFP (AtVIPP1-GFP) in tobacco (Nicotiana tabacum) chloroplasts and performed transmission electron microscopy (TEM). A purified AtVIPP1-GFP fraction was enriched with long filamentous tubule-like structures. Detailed TEM observations of chloroplasts in fixed resin-embedded tissues identified VIPP1 assemblies in situ that appeared to colocalize with GFP fluorescence. Electron tomography demonstrated that the AtVIPP1 oligomers consisted of bundled filaments near membranes, some of which appeared connected to the TM or inner chloroplast envelope at their contact sites. The observed bundles were never detected in wild-type Arabidopsis but were observed in Arabidopsis vipp1 mutants expressing AtVIPP1-GFP. Taken together, we propose that the bundled filaments are the dominant AtVIPP1 oligomers that represent its static state in vivo
Integration of Cholesterol Oxidase‐Based Biosensors on a Smart Contact Lens for Wireless Cholesterol Monitoring from Tears
Full text linkCholesterol plays a critical role in physiological functions, but elevated levels increase the risk of cardiovascular disease. Regular cholesterol monitoring is essential for elderly or obese individuals. Current methods, such as blood tests, are invasive, inconvenient, and require a professional operator. In contrast, tears, as an accessible body fluid, offer a promising alternative for noninvasive monitoring due to their correlation with blood cholesterol levels. Herein, a noninvasive approach for monitoring cholesterol levels in tears using a biosensor integrated into a smart contact lens is reported. The biosensor employs cholesterol oxidases as the biocatalyst, coupled with an osmium-based mediator, to detect cholesterol concentrations ranging from 0.1 mM to 1.2 mM in artificial tears. A key challenge is the extremely low cholesterol concentration in tears, which is addressed using a parity-time (P-T) symmetry-based magnetic resonance coupling system. This system enables wireless signal reading and achieves high sensitivity due to its high-quality (Q) factor, which can achieve a detection limit of 0.061 mM. This portable, high-sensitivity smart contact lens demonstrates significant potential as a wearable device for continuous, noninvasive cholesterol monitoring. The findings contribute to advancing tear-based diagnostic systems and highlight the scientific importance of utilizing tear biomarkers for health monitoring
Specific induction of right ventricular-like cardiomyocytes from human pluripotent stem cells
Full text linkBackground Applications employing human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) require well-characterized, chamber-specific hPSC-CMs. Distinct first heart field (FHF) and second heart field (SHF) cardiac progenitor populations give rise to the left ventricular (LV) and right ventricular (RV) cardiomyocytes, respectively. This developmental difference in cardiomyocyte origin suggests that chamber-specific cardiomyocytes have unique characteristics. Therefore, efficient strategies to differentiate human pluripotent stem cells (hPSCs) specifically to LV-like or RV-like cardiomyocytes are needed and it is still unknown whether there is a phenotypic difference between LV-like cardiomyocytes and RV-like cardiomyocytes derived from hPSCs.
Methods An established hPSC cardiac differentiation protocol employing sequential GSK3β inhibition followed by Wnt inhibition (GiWi) was modified by addition of insulin or BMP antagonists during mesoderm formation. Cardiac progenitor populations were evaluated for FHF and SHF markers, and differentiated hPSC-CMs were characterized for chamber-specific markers.
Results The GiWi protocol produced mainly FHF-like progenitor cells that gave rise to LV-like cardiomyocytes. Inhibition of endogenous BMP signaling during mesoderm induction using insulin or BMP antagonists reduced expression of FHF markers and increased expression of SHF markers in cardiac progenitor cells. hPSC-CMs arising from the SHF-like progenitor cells showed an RV-like gene expression pattern and exhibited phenotypic differences in spontaneous contraction rate, Ca2+ transients, and cell size compared to control LV-like cardiomyocytes.
Conclusion This study establishes methodology to generate RV-like hPSC-CMs to support the development of disease modeling research using chamber-specific hPSC-CMs
Responding to humor online: an exploratory L2 study on the effect of instruction
Full text linkAlthough L2 learners report having great difficulty responding to humour, research on this area is lacking. There is also a relative lack of studies on whether there is the need for humour instruction for European learners of other European languages. Therefore, this pilot study explored instruction on humour responses for learners of French at a Dutch university. Participants reported that humour instruction is warranted in their B2-level French class
Muscle morphological adaptations to resistance training and sports participation in children and adolescents: a scoping review
Full text linkIntroduction: This scoping review aimed to systematically map the existing literature on the effects of resistance training (RT) and sports participation on muscle morphology in children and adolescents.
Methods: Herein, a literature search was conducted using three electronic databases: PubMed, Scopus, and Web of Science. The inclusion criteria were as follows: articles that were written in English, which used chronic RT or a combination of RT with other training methods, or investigated the effects of sports participation, and reported muscle morphology as an outcome.
Results: This scoping review included 29 studies: 17 cross-sectional studies, 3 prospective observational studies, and 9 interventional studies. The following distribution was obtained after categorizing the included studies according to participant age: aged 6–11 years, 12 articles; aged 12–14 years, 10 articles; and aged 15–17 years, 10 articles. The designs of interventional studies included eight quasi-experimental parallel-group trials and a quasi-experimental crossover trial. However, none of the included interventional studies followed the CONSORT guidelines for conducting randomized controlled trials. Across the included studies, 14 different sports were analyzed for their effects on muscle morphology. Four studies combined players from various sports. In the included studies, 47 different muscles or muscle groups were examined. Our results identified unexplored muscles because our included studies did not examine the volume of lower leg muscles.
Conclusion: Future research directions in this field, including experimental design and targeted muscles, are warranted
An Automatic Code Generation Tool Using Generative Artificial Intelligence for Element Fill-in-the-Blank Problems in a Java Programming Learning Assistant System
Full text linkPresently, Java is a fundamental object-oriented programming language that can be mastered by any student in information technology or computer science. To assist both teachers and students, we developed the Java Programming Learning Assistant System (JPLAS). It offers several types of practice problems with different levels and learning goals for step-by-step self-study, where any answer is automatically marked in the system. One challenge for teachers that is addressed with JPLAS is the generation of proper exercise problems that meet learning requirements. We implemented programs for generating new problems from given source codes, as collecting and evaluating suitable codes remains time-consuming. In this paper, we present an automatic code generation tool using generative AI to solve this challenge. Prompt engineering is used to help generate an appropriate source code, and the quality is controlled by optimizing the prompt based on the outputs. For applications in JPLAS, we implement a web application system to automatically generate an element fill-in-the-blank problem (EFP) in JPLAS. For evaluation, we select the element fill-in-the-blank problem (EFP) as the target type in JPLAS and generate several instances using this tool. The results confirm the validity and effectiveness of the proposed method
Lyme neuroborreliosis in Japan: Borrelia burgdorferi sensu lato as a cause of meningitis of previously undetermined etiology in hospitalized patients outside of the island of Hokkaido, 2010–2021
Full text linkBackground and Purpose: Clinical manifestations of Lyme borreliosis (LB), caused by Borrelia burgdorferi sensu lato (Bbsl), include erythema migrans, Lyme neuroborreliosis (LNB), carditis, and arthritis. LB is a notifiable disease in Japan with
Methods: Investigators at 15 hospitals in 10 prefectures throughout Japan retrieved serum and/or cerebrospinal fluid (CSF) samples collected in 2010–2021 from 517 patients hospitalized with encephalitis or meningitis which had an etiology that had not been determined. Samples were tested for Bbsl-specific antibodies using ELISA and Western blot tests. In alignment with the European Union LNB case definition, a confirmed LNB case had CSF pleocytosis and intrathecal production of Bbsl-specific antibodies and a probable LNB case had a CSF sample with pleocytosis and Bbsl-specific antibodies.
Results: LNB was identified in three hospitalized patients with meningitis of previously undetermined etiology: a male resident of Aomori Prefecture was a confirmed LNB case, and two female residents of Oita Prefecture were probable LNB cases. None of the patients with confirmed or probable LNB had traveled in the month prior to symptom onset and none had samples previously tested for LB.
Conclusion: The identification of previously undiagnosed LNB cases indicates a need for enhanced disease awareness in Japan, particularly beyond Hokkaido Island, and more readily available LB diagnostic testing
Parieto-Occipital Disconnection for Drug-Resistant Parieto-Occipital Lobe Epilepsy: A Case Report and Surgical Technique
Full text linkWe report a case of drug-resistant parieto-occipital lobe epilepsy successfully treated with parieto-occipital disconnection (POD). An 18-year-old left-handed female, who had undergone surgery for an acute subdural hematoma at 10 months of age, developed drug-resistant epilepsy at age 15. Despite antiepileptic drug treatment, her seizures remained uncontrolled, and at age 18 she was referred to our hospital for evaluation. Magnetic resonance imaging (MRI) revealed atrophy in the left occipital and parietal lobes. Ictal electroencephalography (EEG) confirmed occipital onset of seizures without temporal lobe involvement. She had pre-existing homonymous hemianopsia. POD surgery was performed, carefully preserving the temporal lobe structures. Postoperatively, she experienced transient right-sided paresis, which fully resolved, and achieved complete seizure control at 3 years without memory loss. This case demonstrates that POD, a rare surgical approach, is a viable option for parieto-occipital lobe epilepsy, effectively controlling seizures while minimizing functional impairment in the absence of temporal lobe involvement
A Case of Surgical Treatment for a Large Pulmonary Artery Aneurysm with a Quadricuspid Pulmonary Valve
Full text linkA 65-year-old man was referred to our hospital for the annual assessment of the diameter and dilation of a pulmonary artery (PA) aneurysm. He had a small ventricular septal defect (VSD) that had closed naturally. Echocardiography revealed a dilated main PA, mild pulmonary regurgitation and no VSD. Computed tomography confirmed the dilation of the main PA (66.7×47.8 mm), right PA (37.1×32.9 mm), and left PA (36.7×34.0 mm). The patient underwent pulmonary artery replacement using a prosthetic vascular graft. A quadricuspid pulmonary valve was identified intraoperatively. Early surgical intervention could help to prevent rupture and dissection of PA aneurysms
Occupational motions such as kneeling and squatting are associated with the increased development of medial meniscus posterior root tears, regardless of the medial posterior tibial slope angle
Full text linkPurpose: The relationship between occupational motions and the medial posterior tibial slope (MPTS) with the development of medial meniscus posterior root tears (MMPRTs) has not been investigated. The development of non-traumatic degenerative MMPRTs may be influenced by repetitive occupational motions and bone morphological characteristics. Herein, we examined the association between occupational motions and MPTS in patients with MMPRT development.
Methods: During the first medical examination, MPTS was measured using lateral knee radiographic images, and occupational motions were investigated in 559 patients (591 knees). Occupational motions were classified as kneeling and squatting, standing and walking, sitting, lifting heavy weights, and housework. Mann–Whitney U test was used to compare patient characteristics between male and female patients and MPTS relative to occupational motion.
Results: The most frequent occupational motion was housework (160/559 patients, 28.6%), followed by kneeling and squatting (140/559, 25.0%), standing and walking (128/559, 22.9%), sitting (82/559, 14.7%), and lifting heavy weights (49/559, 8.8%). Furthermore, housework (10.0 ± 2.6°) involved significantly greater MPTS than kneeling and squatting (9.3 ± 2.7°; p = 0.012). However, the MPTS associated with other occupational motions was not significantly different from that associated with housework.
Conclusion: The most frequent occupational motion among patients with MMPRTs was housework, followed by kneeling and squatting. Patients who performed housework tended to have a higher MPTS. Occupational motions such as kneeling and squatting potentially increase the development of MMPRTs, even without a high MPTS.
Level of Evidence: Level IV