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Abstract RNA interference (RNAi) is a gene-silencing mechanism triggered by the cytosolic entry of double-stranded RNAs (dsRNAs). Many animal cells internalize extracellular dsRNAs via endocytosis for RNAi induction. However, it is not clear how the endocytosed dsRNAs are translocated into the cytosol across the endo/lysosomal membrane. Herein, we show that in Drosophila S2 cells, endocytosed dsRNAs induce lysosomal membrane permeabilization (LMP) that allows cytosolic dsRNA translocation. LMP mediated by dsRNAs requires the lysosomal Cl−/H+ antiporter ClC-b/DmOstm1. In clc-b or dmostm1 knockout S2 cells, extracellular dsRNAs are endocytosed and reach the lysosomes normally but fail to enter the cytosol. Pharmacological induction of LMP restores extracellular dsRNA-directed RNAi in clc-b or dmostm1-knockout cells. Furthermore, clc-b or dmostm1 mutant flies are defective in extracellular dsRNA-directed RNAi and its associated antiviral immunity. Therefore, endocytosed dsRNAs have an intrinsic ability to induce ClC-b/DmOstm1-dependent LMP that allows cytosolic dsRNA translocation for RNAi responses in Drosophila cells.

Abstract Reactive nitrogen negatively affects terrestrial ecosystems by excessive deposition. Nitric acid gas (HNO3), a component of reactive nitrogen, is readily deposited on ground surfaces due to its high reactivity. However, there have been recent cases in which suppressed deposition fluxes, including upward fluxes, were observed above forests. As the mechanisms of HNO3 dry deposition on forest surfaces are not fully understood, the accuracy of dry deposition estimates remains uncertain. To reduce uncertainties in the estimation, we investigated dry deposition of HNO3 by 1-year measurement in a forest. We measured the vertical profiles of HNO3, nitrate, and sulfate in PM2.5 in a deciduous forest in suburban Tokyo (FM Tama). We observed their concentrations above the forest canopy (30 m) and near the forest floor (2 and 0.2 m) using the denuder/filter pack from October 2020 to September 2021. The HNO3 concentration decreased significantly from 30 to 2 m. However, the decrease in HNO3 was not as significant, and occasionally, emission profiles were produced between 2 and 0.2 m. This was likely caused by HNO3 generated by the volatilization of NH4NO3 near the forest floor, which was warmed by sunlight during daytime in both leafy and leafless periods. Conversely, HNO3 concentrations at 30 m were much higher than those at 2 m and 0.2 m, indicating that the forest acted as a sink for HNO3 from a long-term perspective. It is presumed that HNO3, generated just above the forest canopy, could cause an upward flux if a temperature difference of several degrees occurs between 25 and 20 m.

Summary: Although oral tolerance is a critical system in regulating allergic disorders, the mechanisms by which dietary factors regulate the induction and maintenance of oral tolerance remain unclear. To address this, we explored the differentiation and function of various immune cells in the intestinal immune system under fasting and ad libitum-fed conditions before oral ovalbumin (OVA) administration. Fasting mitigated OVA-specific Treg expansion, which is essential for oral tolerance induction. This abnormality mainly resulted from functional defects in the CX3CR1+ cells responsible for the uptake of luminal OVA and reduction of tolerogenic CD103+ dendritic cells. Eventually, fasting impaired the preventive effect of oral OVA administration on asthma and allergic rhinitis development. Specific food ingredients, namely carbohydrates and arginine, were indispensable for oral tolerance induction by activating glycolysis and mTOR signaling. Overall, prior food intake and nutritional signals are critical for maintaining immune homeostasis by inducing tolerance to ingested food antigens.

Inhibitory natural killer (NK) cell receptors recognize MHC class I (MHC-I) in trans on target cells and suppress cytotoxicity. Some NK cell receptors recognize MHC-I in cis, but the role of this interaction is uncertain. Ly49Q, an atypical Ly49 receptor expressed in non-NK cells, binds MHC-I in cis and mediates chemotaxis of neutrophils and type I interferon production by plasmacytoid dendritic cells. We identified a lipid-binding motif in the juxtamembrane region of Ly49Q and found that Ly49Q organized functional membrane domains comprising sphingolipids via sulfatide binding. Ly49Q recruited actin-remodeling molecules to an immunoreceptor tyrosine-based inhibitory motif, which enabled the sphingolipid-enriched membrane domain to mediate complicated actin remodeling at the lamellipodia and phagosome membranes during phagocytosis. Thus, Ly49Q facilitates integrative regulation of proteins and lipid species to construct a cell type-specific membrane platform. Other Ly49 members possess lipid binding motifs; therefore, membrane platform organization may be a primary role of some NK cell receptors.

Until now, 9 cases of an association of a posterior inferior cerebellar artery (PICA) aneurysm with the persistent primitive hypoglossal artery (PPHA) have been reported. We reported a case of a ruptured PICA aneurysm associated with the PPHA, which was successfully treated by intravascular embolization using inflation of an endovascular occlusion balloon in the proximal artery to stabilize the microcatheter tip. A 19-year-old woman presenting headache and mild consciousness disturbance was admitted to our hospital. Head computed tomography (CT) showed a subarachnoid hemorrhage in the interpeduncular cistern. Right common carotid angiography revealed an aneurysm with a maximum diameter of 3.7 mm at the proximal PICA, which was fed from the common carotid artery (CCA) through the internal carotid artery (ICA) and the PPHA and the vertebral artery. During coil embolization, a pulsatile fluctuation of the microcatheter tip caused by the minimum curvature of the proximal arterial route from the aorta to the PPHA made the continuation of the coil embolization difficult. Then, we inflated an occlusion balloon in the PPHA to stabilize the microcatheter tip, and the coil embolization was performed under the blank roadmap fluoroscopy. The aneurysm disappeared completely with the preservation of the PICA on the postoperative angiogram. A case of ruptured PICA aneurysm with proximal PPHA, which was successfully embolized with the assist of a proximal occlusion balloon inflation. When the pulsative movement of a microcatheter tip made coil embolization difficult, this technique could be useful.

Abstract Background The efficacy of anterior fusion with overcorrection in the instrumented vertebra for Lenke 1 AR type curves has been reported, but how to achieve overcorrection and how overcorrection affects spinal alignment are unclear. The purpose of this study was to identify the factors that cause overcorrection, and to investigate how overcorrection affects postoperative spinal alignment in the surgical treatment of Lenke 1 AR type curves. Methods Patients who had anterior surgery for a Lenke type 1 or 2 and lumbar modifier AR (L4 vertebral tilt to the right) type scoliosis and minimum 2-year follow-up were included. The radiographic data were measured at preoperative, postoperative 1 month, and final follow-up. The UIV-LIV Cobb angle was determined as the Cobb angle between the upper instrumented vertebra (UIV) and the lower instrumented vertebra (LIV), and a negative number for this angle was considered overcorrection. The screw angle was determined to be the sum of the angle formed by the screw axis and the lower and upper endplates in the LIV and UIV, respectively. The change (Δ) in the parameters from postoperative to final follow-up was calculated. The relationships between the UIV-LIV Cobb angle and other radiographic parameters were evaluated by linear regression analyses. Results Fourteen patients met the inclusion criteria. Their median age was 15.5 years, and the median follow-up period was 53.6 months. The median UIV-LIV Cobb angle was –1.4° at postoperative 1 month. The median screw angle was 4.7°, and overcorrection was achieved in 11 (79%) cases at postoperative 1 month. The screw angle (r 2 = 0.42, p = 0.012) and Δ FDUV-CSVL (the deviation of the first distal uninstrumented vertebra from the central sacral vertical line, r 2 = 0.53, p = 0.003) were significantly correlated with the UIV-LIV Cobb angle. Conclusions Screw placement in the UIV and LIV not parallel to the endplate, but angled, was an effective method to facilitate overcorrection in the instrumented vertebrae. The results of the present study suggest that overcorrection could bring spontaneous improvement of coronal balance below the instrumented segment during the postoperative period.

Abstract Background A tap test is established as an evaluation method to indicate shunt surgery for hydrocephalus, especially idiopathic normal pressure hydrocephalus (iNPH). The timing of gait assessment after the test is still controversial, while some studies reported the effectiveness of the gait evaluation up to 2nd day after tap tests. Our study explored whether the gait evaluation on the 7th day after a tap test is necessary. Methods We retrospectively evaluated 129 consecutive cases with possible iNPH who performed gait assessment on all 1st, 3rd, and 7th days after tap tests between May 2020 and February 2022. We reviewed the following items of the patients: age, sex, modified Rankin scale, iNPH grading scale, Mini-Mental State Evaluation (MMSE), and neurological imaging. The number of probable iNPH patients who improved their gait each day after the test was analyzed. We also assessed the number of definite iNPH patients and revealed the background characteristics of the patients who showed gait improvement on the 7th day after the tests. Results Of the 129 patients who met our inclusion criteria, 57 were judged as probable iNPH on the 1st day, 28 were new on the 3rd, and 23 were new on the 7th. The number of probable iNPH patients up to the 7th day after tests was significantly more extensive than that of those up to the 3rd (108 [83.7%] vs. 85 [65.9%]; 95% confidence interval [CI], p

We propose a method for increasing power extraction from a thermoelectric generator (TEG) by switching between series/parallel circuit configurations of thermoelectric elements, which can adjust the internal impedance of the TEG. The power characteristics of the TEG can be adjusted to the load characteristics of the connected device and the relevant ambient temperature. In this paper, we analyzed the change in the TEG characteristics with the series/parallel switching function. We evaluated the power supply to the connected devices at different ambient temperatures and different series/parallel configurations and confirmed that the extracted power could be increased. By theoretically analyzing the circuit configuration of the thermoelectric devices, the switching required to improve the power extraction, and the temperature difference at which switching occurred, we devised a design method for a TEG with circuit switching in order to increase power extraction with any device. We demonstrated the configuration of switching by using a system in which a TEG supplied power to an external wireless transmitter circuit. In this system, the optimal configuration differed at temperature differences of 3.0 K and 4.0 K. At a temperature difference of 3.0 K, the 2-series/1-parallel configuration provided 10% more power to the external circuit than the 1-series/2-parallel configuration. On the other hand, at the temperature difference of 4.0 K, the 1-series/2-parallel configuration provided 23% more power than the 2-series/1-parallel configuration.

Metabolic pathways are plastic and rapidly change in response to stress or perturbation. Current metabolic profiling techniques require lysis of many cells, complicating the tracking of metabolic changes over time after stress in rare cells such as hematopoietic stem cells (HSCs). Here, we aimed to identify the key metabolic enzymes that define differences in glycolytic metabolism between steady-state and stress conditions in murine HSCs and elucidate their regulatory mechanisms. Through quantitative 13C metabolic flux analysis of glucose metabolism using high-sensitivity glucose tracing and mathematical modeling, we found that HSCs activate the glycolytic rate-limiting enzyme phosphofructokinase (PFK) during proliferation and oxidative phosphorylation (OXPHOS) inhibition. Real-time measurement of ATP levels in single HSCs demonstrated that proliferative stress or OXPHOS inhibition led to accelerated glycolysis via increased activity of PFKFB3, the enzyme regulating an allosteric PFK activator, within seconds to meet ATP requirements. Furthermore, varying stresses differentially activated PFKFB3 via PRMT1-dependent methylation during proliferative stress and via AMPK-dependent phosphorylation during OXPHOS inhibition. Overexpression of Pfkfb3 induced HSC proliferation and promoted differentiated cell production, whereas inhibition or loss of Pfkfb3 suppressed them. This study reveals the flexible and multilayered regulation of HSC glycolytic metabolism to sustain hematopoiesis under stress and provides techniques to better understand the physiological metabolism of rare hematopoietic cells.

Surgery on spinal tumors becomes challenging when the tumor is ventral to the spinal cord. Conventionally, we approach it posteriorly through bilateral laminectomy and rotate the cord after sectioning the dentate ligament and nerve roots. However, manipulating the cord can be hazardous, and a long bilateral laminectomy can be invasive. Meanwhile, a narrow operative field and a limited lateral viewing angle in a unilateral approach constrained the surgeon. To overcome these problems, we previously reported a technique of modified unilateral approach where we incised the skin and the fascia horizontally and placed a pair of retractors longitudinally. The current article reports our experience applying this approach in 15 patients with ventrally located spinal tumors. The approach was performed on 10 schwannomas, 2 meningiomas, and 3 others. We evaluated paraspinal muscle atrophy on postoperative magnetic resonance imaging. The modified unilateral approach provided an excellent surgical field for removing ventrally located tumors. Gross total removal was achieved in 11 patients (92% of benign tumors). No neurological complications occurred except for one case of transient weakness. We encountered no wound-related late complications such as pain or deformity. The reduction of the cross-sectional area of the paraspinal muscles on the approach side (compared to the nonapproach side) was 0.93 (95% confidence interval: 0.72-1.06), indicating 7% atrophy (statistically nonsignificant, p = 0.48). We believe this simple technique can be useful for removing spinal tumors located ventral to the spinal cord.

Background: Hospitalization with a first episode of heart failure (HF) is a serious event associated with poor clinical outcomes in HF with preserved ejection fraction (HFpEF). Identification of HFpEF via detection of elevated left ventricular filling pressure at rest or during exercise may allow early intervention. Benefits of treatment with mineralocorticoid receptor antagonists (MRAs) in established HFpEF have been reported, but use of MRAs is not well studied in early HFpEF without prior HF hospitalization. Methods: We retrospectively studied 197 patients with HFpEF who did not have prior hospitalization but had been diagnosed by exercise stress echocardiography or catheterization. We examined changes in natriuretic peptide levels and echocardiographic parameters reflecting diastolic function following MRA initiation. Results: Of the 197 patients with HFpEF, MRA treatment was initiated for 47 patients. After a median 3-month follow-up, reduction in N-terminal pro-B-type natriuretic peptide levels from baseline to follow-up was greater in patients treated with MRA than in those who were not (median, -200 pg/mL [interquartile range, -544 to -31] vs 67 pg/mL [interquartile range, -95 to 456], P < 0.0001 in 50 patients with paired data). Similar results were observed for the changes in B-type natriuretic peptide levels. Reduction in the left atrial volume index was also greater in the MRA-treated group than in the non-MRA-treated group after a median 7-month follow-up (77 patients with paired echocardiographic data). Patients with lower left ventricular global longitudinal strain experienced a greater reduction in N-terminal pro-B-type natriuretic peptide levels following MRA treatment. In the safety assessment, MRA modestly decreased renal function but did not change potassium levels. Conclusions: Our results suggest that MRA treatment has potential benefits for early-stage HFpEF. Résumé: Contexte: L'hospitalisation consécutive à un premier épisode d'insuffisance cardiaque (IC) est un événement grave associé à des résultats cliniques médiocres dans l'IC à fraction d’éjection préservée (ICFEP). Or, la détection d'une pression de remplissage ventriculaire gauche élevée au repos ou à l'effort peut permettre de déceler une ICFEP et d’intervenir de façon précoce. Par ailleurs, le recours à des antagonistes des récepteurs minéralocorticoïdes (ARM) serait bénéfique dans les cas d’ICFEP, mais leur utilisation n'a pas été bien étudiée dans l’ICFEP précoce sans hospitalisation préalable pour cause d'insuffisance cardiaque. Méthodologie: Nous avons étudié rétrospectivement 197 patients atteints d’ICFEP qui n'avaient pas été hospitalisés auparavant, mais dont la maladie avait été diagnostiquée par une échocardiographie de stress ou un cathétérisme. Après l’instauration des ARM, nous avons examiné les variations des taux de peptides natriurétiques et des paramètres échocardiographiques reflétant la fonction diastolique. Résultats: Sur les 197 patients atteints d’ICFEP, 47 ont entamé un traitement par des ARM. Après un suivi médian de trois mois, la réduction des taux de propeptides natriurétiques de type B N-terminal (NT-proBNP) entre la valeur initiale et le suivi était plus importante chez les patients traités par des ARM que chez ceux qui ne l'étaient pas (médiane : -200 pg/ml [écart interquartile : -544 à -31] contre 67 pg/ml [écart interquartile : -95 à 456], p < 0,0001 chez 50 patients ayant des données appariées). Des résultats similaires ont été observés pour la variation des taux de peptides natriurétiques de type B. La réduction du volume de l'oreillette gauche était également plus importante dans le groupe traité par des ARM que dans le groupe témoin après un suivi médian de sept mois (données échocardiographiques appariées pour 77 patients). Les patients présentant une déformation longitudinale globale du ventricule gauche plus faible ont connu une réduction plus importante des taux de NT-proBNP après le traitement par des ARM. Enfin, lors de l'évaluation de l’innocuité, les ARM ont légèrement altéré la fonction rénale, mais sans modifier les taux de potassium. Conclusions: Ces résultats semblent indiquer que le traitement par des ARM présente des avantages potentiels dans les cas d’ICFEP au stade précoce.

Abstract Cardiopulmonary exercise testing (CPET) may potentially differentiate heart failure (HF) with preserved ejection fraction (HFpEF) from noncardiac causes of dyspnea (NCD). While contemporary guidelines for HF recommend using CPET for identifying causes of unexplained dyspnea, data supporting this practice are limited. This study aimed to determine the diagnostic value of expired gas analysis to distinguish HFpEF from NCD. Exercise stress echocardiography with simultaneous expired gas analysis was performed in patients with HFpEF (n = 116) and those with NCD (n = 112). Participants without dyspnea symptoms were also enrolled as controls (n = 26). Exercise capacity was impaired in patients with HFpEF than in controls and those with NCD, evidenced by lower oxygen consumption (VO2), but there was a substantial overlap between HFpEF and NCD. Receiver operating characteristic curve analyses showed modest diagnostic abilities of expired gas analysis data in differentiating individuals with HFpEF from the controls; however, none of these variables clearly differentiated between HFpEF and NCD (all areas under the curve

Aims: Anemia is common in patients with heart failure with preserved ejection fraction (HFpEF) and is associated with exercise intolerance. However, there are limited data on how anemia contributes to reduced exercise capacity in patients with HFpEF. We aimed to characterize exercise capacity, cardiovascular and ventilatory reserve, and the oxygen (O2) pathway in anemic patients with HFpEF. Methods: A total of 238 patients with HFpEF and 248 dyspneic patients without HF underwent ergometry exercise stress echocardiography with simultaneous expired gas analysis. Patients with HFpEF were classified into two groups based on the presence of anemia (hemoglobin

Amino acid transporters are generally recognized as machinery that transport amino acids from the extracellular environment into the cytoplasm. Although their primary function is the uptake of amino acids to supply the cell with nutrients and energy, endolysosome-resident amino acid (EL-aa) transporters possess several unique functions in accordance with their localization in intracellular vesicular membranes. They play pivotal roles in the maintenance of metabolic homeostasis via direct involvement in the amino acid sensing pathway, which regulates the activity of mechanistic target of rapamycin complex 1 (mTORC1), a master regulator of cellular metabolism. Additionally, some EL-aa transporters contribute to the maintenance of dynamic homeostasis of endolysosomes, including the regulation of endolysosomal acidity, by carrying amino acids out of endolysosomes. In addition, EL-aa transporters act as a scaffold to gather signaling molecules and multiple enzymes to control cellular metabolism on the endolysosomal membrane. Among EL-aa transporters, solute carrier family 15 member 4 (SLC15A4) is preferentially expressed in immune cells, including macrophages, dendritic cells, and B cells, and plays a key role in the integration of metabolic and inflammatory signals. In this review, we summarize our recent findings on EL-aa transporter contributions to inflammatory and metabolic signaling in the endolysosomes of immune cells by focusing on the SLC15 family, including SLC15A4 and SLC15A3, and discuss their uniqueness and universality. We also discuss the potential of targeting these EL-aa transporters in immune cells for the development of novel therapeutic strategies for inflammatory diseases. Because these transporters are highly expressed in immune cells and significantly alter the functions of immune cells, targeting them would provide a great advantage in ensuring a wide safety margin.

Shu Hashimoto1,2 ,† Yuri Yoshida,3 Naoyuki Makita,3 Ryoko Sorimachi,3 Satoko Sugaya,4 Yoshifumi Arita,3 Nobuya Hayashi,4 Naoki Tashiro,3 Masakazu Ichinose5,6 1Nihon University, Tokyo, Japan; 2Hibiya Kokusai Clinic, Tokyo, Japan; 3Medical Department, AstraZeneca K.K., Osaka, Japan; 4R&D, AstraZeneca K.K., Osaka, Japan; 5Academic Center of Osaki Citizen Hospital, Miyagi, Japan; 6Department of Respiratory Medicine, Tohoku University Graduate School of Medicine, Miyagi, Japan†Dr Shu Hashimoto passed away on July 03, 2022Correspondence: Masakazu Ichinose, Academic Center of Osaki Citizen Hospital, 3-8-1 Honami, Furukawa, Osaki, 989-6183, Japan, Tel +81-229-23-3311, Fax +81-229-23-5380, Email ichinose@h-osaki.jpIntroduction: The ACO Japan Cohort Study, a multicenter observational study, investigated the proportion of patients with chronic obstructive pulmonary disease (COPD) who met the Japanese Respiratory Society (JRS) asthma–COPD overlap (ACO) diagnostic criteria, characteristics of ACO and non-ACO patients, and the patient transitions between ACO/non-ACO diagnosis over 2 years.Patients and Methods: Patients with COPD were consecutively enrolled between June and December 2018 and followed up continuously for 2 years. All participating study sites were medical institutions where respiratory specialists routinely conducted medical examinations/tests required for ACO diagnosis.Results: Among 708 patients with COPD, 101 (14.3%), 118 (16.7%), and 125 (17.7%) were diagnosed with ACO at registration, 1 year, and 2 years, respectively. In total, 22.6% of patients lacked the data necessary for ACO diagnosis throughout the 2 years. Among patients who had the necessary data for ACO diagnosis, 24.7% were diagnosed with ACO at 2 years. More ACO patients had moderate or severe exacerbations in the past year than non-ACO patients at registration (15.8% vs 6.3%, p = 0.049) and 1 year (19.4% vs 7.6%, p = 0.025). ACO patients had a greater decrease in mean forced expiratory volume in one second over 2 years than non-ACO patients (− 92.0 vs 43.4 mL). Among patients diagnosed with ACO at registration, 21.4% transitioned to non-ACO after 1 year. Conversely, almost all non-ACO patients at registration remained non-ACO after 1 year.Conclusion: COPD patients with ACO determined by the JRS criteria had a high risk of exacerbations and a rapid decline in respiratory function, indicating that the JRS criteria for ACO are useful for identifying high-risk COPD patients. Testing necessary for ACO diagnosis is insufficiently performed even in real-world clinical practice of COPD specialists.Keywords: asthma, chronic obstructive pulmonary disease, exacerbation, FEV1 decline, inhaled corticosteroid

The UFM1 system, a ubiquitin-like conjugation system is crucial for endoplasmic reticulum (ER) homeostasis. Here, authors found that CYB5R3 is covalently conjugated with UFM1, which becomes a signal for ER-phagy, a selective autophagy of ER.