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1.
EMBO J ; 40(12): e107270, 2021 06 15.
Article in English | MEDLINE | ID: mdl-33885174

ABSTRACT

Paraspeckles are constructed by NEAT1_2 architectural long noncoding RNAs. Their characteristic cylindrical shapes, with highly ordered internal organization, distinguish them from typical liquid-liquid phase-separated condensates. We experimentally and theoretically investigated how the shape and organization of paraspeckles are determined. We identified the NEAT1_2 RNA domains responsible for shell localization of the NEAT1_2 ends, which determine the characteristic internal organization. Using the soft matter physics, we then applied a theoretical framework to understand the principles that determine NEAT1_2 organization as well as shape, number, and size of paraspeckles. By treating paraspeckles as amphipathic block copolymer micelles, we could explain and predict the experimentally observed behaviors of paraspeckles upon NEAT1_2 domain deletions or transcriptional modulation. Thus, we propose that paraspeckles are block copolymer micelles assembled through a type of microphase separation, micellization. This work provides an experiment-based theoretical framework for the concept that ribonucleoprotein complexes (RNPs) can act as block copolymers to form RNA-scaffolding biomolecular condensates with optimal sizes and structures in cells.


Subject(s)
Micelles , Polymers , RNA, Long Noncoding , Ribonucleoproteins , Cell Line , Humans
2.
Cancer Sci ; 115(8): 2686-2700, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38877783

ABSTRACT

Application of physical forces, ranging from ultrasound to electric fields, is recommended in various clinical practice guidelines, including those for treating cancers and bone fractures. However, the mechanistic details of such treatments are often inadequately understood, primarily due to the absence of comprehensive study models. In this study, we demonstrate that an alternating magnetic field (AMF) inherently possesses a direct anti-cancer effect by enhancing oxidative phosphorylation (OXPHOS) and thereby inducing metabolic reprogramming. We observed that the proliferation of human glioblastoma multiforme (GBM) cells (U87 and LN229) was inhibited upon exposure to AMF within a specific narrow frequency range, including around 227 kHz. In contrast, this exposure did not affect normal human astrocytes (NHA). Additionally, in mouse models implanted with human GBM cells in the brain, daily exposure to AMF for 30 min over 21 days significantly suppressed tumor growth and prolonged overall survival. This effect was associated with heightened reactive oxygen species (ROS) production and increased manganese superoxide dismutase (MnSOD) expression. The anti-cancer efficacy of AMF was diminished by either a mitochondrial complex IV inhibitor or a ROS scavenger. Along with these observations, there was a decrease in the extracellular acidification rate (ECAR) and an increase in the oxygen consumption rate (OCR). This suggests that AMF-induced metabolic reprogramming occurs in GBM cells but not in normal cells. Our results suggest that AMF exposure may offer a straightforward strategy to inhibit cancer cell growth by leveraging oxidative stress through metabolic reprogramming.


Subject(s)
Brain Neoplasms , Cell Proliferation , Glioblastoma , Magnetic Field Therapy , Metabolic Reprogramming , Oxidative Phosphorylation , Reactive Oxygen Species , Animals , Humans , Mice , Astrocytes/metabolism , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Line, Tumor , Glioblastoma/metabolism , Glioblastoma/pathology , Magnetic Field Therapy/methods , Magnetic Fields , Metabolic Reprogramming/radiation effects , Mitochondria/metabolism , Oxygen Consumption , Reactive Oxygen Species/metabolism , Superoxide Dismutase/metabolism , Xenograft Model Antitumor Assays
3.
Naturwissenschaften ; 111(4): 35, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38916816

ABSTRACT

Whether in ant-aphid mutualism the ants exert evolutionary selection pressure on aphid morphology has not yet been fully tested. Here, we tested whether the long proboscises of Stomaphis yanonis (Aphididae Lachninae) aphids confer an advantage in preventing predation by the tending ants. Specifically, we tested the hypothesis that aphids with a shorter proboscis would excrete less honeydew, making them more likely to be preyed upon by ants. Our results showed that aphid individuals with a shorter proboscis took up less phloem sap and excreted less honeydew than individuals with a longer proboscis. In addition, among aphids with a similar body size, those with a shorter proboscis were more susceptible to predation by ants than those with a longer proboscis. These results suggest that predation by tending ants, by exerting selection pressure on aphid proboscis morphology, has caused the aphids to evolve longer proboscises.


Subject(s)
Ants , Aphids , Predatory Behavior , Animals , Aphids/physiology , Ants/physiology , Predatory Behavior/physiology , Symbiosis/physiology
4.
Circ J ; 88(4): 501-509, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-37813600

ABSTRACT

BACKGROUND: Fractional flow reserve-computed tomography (FFRCT) has not been validated in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) for coronary artery disease due to theoretical difficulties in using nitroglycerin for such patients.Methods and Results: In this single-center study, we prospectively enrolled 21 patients (34 vessels) and performed pre-TAVR FFRCTwithout nitroglycerin, pre-TAVR invasive instantaneous wave-free ratio (iFR) measurements, and post-TAVR FFR measurements using a pressure wire. The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of pre-TAVR FFRCT≤0.80 to predict post-TAVR invasive FFR ≤0.80 were 82%, 83%, 82%, 71%, and 90%, respectively. A receiver operating characteristic analysis demonstrated an optimal cutoff of 0.78 for pre-TAVR FFRCTto indicate post-TAVR FFR ≤0.80, with an area under the curve (AUC) of 0.84, and the counterpart cutoff of pre-TAVR iFR was 0.89 with an AUC of 0.86. CONCLUSIONS: FFRCTwithout nitroglycerin could be a useful non-invasive imaging modality for assessing the severity of coronary artery lesions in patients with severe AS.


Subject(s)
Aortic Valve Stenosis , Coronary Artery Disease , Coronary Stenosis , Fractional Flow Reserve, Myocardial , Transcatheter Aortic Valve Replacement , Humans , Fractional Flow Reserve, Myocardial/physiology , Nitroglycerin , Aortic Valve Stenosis/diagnostic imaging , Aortic Valve Stenosis/surgery , Prospective Studies , Coronary Artery Disease/surgery , Tomography, X-Ray Computed , Predictive Value of Tests , Coronary Vessels , Ischemia/surgery , Coronary Angiography/methods , Severity of Illness Index
5.
Circ J ; 2024 Sep 21.
Article in English | MEDLINE | ID: mdl-39313373

ABSTRACT

BACKGROUND: Proprotein convertase subtilisin/kexin type 9 inhibitors stabilize vulnerable plaque, reducing cardiovascular events. However, manual optical coherence tomography (OCT) analysis of drug efficacy is challenging because of signal attenuation within lipid plaques. METHODS AND RESULTS: Twenty-four patients with thin-cap fibroatheroma were prospectively enrolled and randomized to receive alirocumab (75 mg every 2 weeks) plus rosuvastatin (10 mg/day) or rosuvastatin (10 mg/day) alone. OCT images at baseline and 36 weeks were analyzed manually and with artificial intelligence (AI)-aided software. AI-aided OCT analysis showed significantly greater percentage changes in the alirocumab+rosuvastatin vs. rosuvastatin-alone group in fibrous cap thickness (FCT; median [interquartile range] 212.3% [140.5-253.5%] vs. 88.6% [63.0-119.6%]; P=0.006) and lipid volume (median [interquartile range] -30.8% [-51.8%, -16.6%] vs. -2.1% [-21.6%, 4.3%]; P=0.015). Interobserver reproducibility for changes in minimum FCT and lipid index was relatively low for manual analysis (interobserver intraclass correlation coefficient [ICC] 0.780 and 0.499, respectively), but high for AI-aided analysis (interobserver ICC 0.999 and 1.000, respectively). Agreements between manual and AI-aided OCT analyses of FCT and the lipid index were acceptable (concordance correlation coefficients 0.859 and 0.833, respectively). CONCLUSIONS: AI-aided OCT analysis objectively showed greater plaque stabilization of adding alirocumab to rosuvastatin. Our results highlight the benefits of a fully automated AI-assisted approach for assessing drug efficacy, offering greater objectivity in evaluating serial changes in plaque stability vs. conventional OCT assessment.

6.
J Oral Pathol Med ; 53(5): 310-320, 2024 May.
Article in English | MEDLINE | ID: mdl-38693616

ABSTRACT

BACKGROUND: Various antigen-presenting cells and tumor cells-expressing PD-L1 inhibits antitumor immune responses in the tumor microenvironment. Recently, numerous studies have shown that tumor cell intrinsic PD-L1 also plays important roles in tumor growth and progression. On the other hand, oral squamous cell carcinoma (OSCC) cells overexpress epidermal growth factor receptor (EGFR) and EGFR signal pathway exacerbates tumor progression. Therefore, this study assessed whether tumor-intrinsic PD-L1 facilitates malignant potential of OSCC cells through regulation of EGFR signaling. METHODS: Two OSCC cell lines, SAS and HSC-3, were transfected with PD-L1 and EGFR-specific small interfering RNA (siRNA). Influences of PD-L1 knockdown on malignant potentials of OSCC cells were examined by Cell Counting kit-8 assay, transwell assay, sphere formation assay, flow cytometry, and Western blot. Effects of PD-L1 and EGFR knockdown on each expression were examined by quantitative real-time PCR (qRT-PCR), Western blot, and flow cytometry. RESULTS: Transfection of an PD-L1-siRNA into OSCC cells decreased the abilities of proliferation, stemness, and mobility of these cells significantly. PD-L1 knockdown also decreased EGFR expression through the promotion of proteasome- and lysosome-mediated degradation and following activation of the EGFR/protekin kinase B (AKT) signal pathway. Meanwhile, EGFR knockdown did not influence PD-L1 expression in SAS and HSC-3 cells, but treatment with a recombinant human EGF induced its expression. Treatment with erlotinib and cetuximab suppressed rhEGF-induced PD-L1 expression and localization in the cellular membrane of both OSCC cells. CONCLUSION: OSCC cells-expressing PD-L1 induced by EGF stimulation may promote malignancy intrinsically via the activation of the EGFR/AKT signaling cascade.


Subject(s)
B7-H1 Antigen , Carcinoma, Squamous Cell , ErbB Receptors , Mouth Neoplasms , Proto-Oncogene Proteins c-akt , Signal Transduction , Humans , ErbB Receptors/metabolism , B7-H1 Antigen/metabolism , Mouth Neoplasms/pathology , Mouth Neoplasms/metabolism , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/metabolism , Cell Line, Tumor , Proto-Oncogene Proteins c-akt/metabolism , Cell Proliferation
7.
Cereb Cortex ; 33(23): 11408-11419, 2023 11 27.
Article in English | MEDLINE | ID: mdl-37814358

ABSTRACT

Motivation facilitates motor performance; however, the neural substrates of the psychological effects on motor performance remain unclear. We conducted a functional magnetic resonance imaging experiment while human subjects performed a ready-set-go task with monetary incentives. Although subjects were only motivated to respond quickly, increasing the incentives improved not only reaction time but also peak grip force. However, the trial-by-trial correlation between reaction time and peak grip force was weak. Extensive areas in the mesocortical system, including the ventral midbrain (VM) and cortical motor-related areas, exhibited motivation-dependent activity in the premovement "Ready" period when the anticipated monetary reward was displayed. This premovement activity in the mesocortical system correlated only with subsequent peak grip force, whereas the activity in motor-related areas alone was associated with subsequent reaction time and peak grip force. These findings suggest that the mesocortical system linking the VM and motor-related regions plays a role in controlling the peak of force generation indirectly associated with incentives but not the initiation of force generation.


Subject(s)
Brain Mapping , Motivation , Humans , Brain Mapping/methods , Reward , Cognition , Reaction Time , Magnetic Resonance Imaging/methods
8.
Heart Vessels ; 39(8): 735-745, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38526753

ABSTRACT

BACKGROUND: Murray law-based quantitative flow ratio (µQFR) is a novel computational method that enables accurate estimation of fractional flow reserve (FFR) using a single angiographic projection. However, its diagnostic value in patients with severe aortic stenosis (AS) remains unclear. METHOD: We included 25 consecutive patients who underwent transcatheter aortic valve replacement (TAVR) for severe AS with intermediate or greater (30-90%) coronary artery disease (CAD). Pre- and post-TAVR µQFR, QFR, instantaneous flow reserve (iFR), and post-TAVR invasive FFR values were measured. We evaluated the diagnostic performance of pre-TAVR µQFR, QFR, and iFR using post-TAVR FFR ≤ 0.80 as a reference standard of ischemia. RESULT: Pre-TAVR µQFR was significantly correlated with post-TAVR FFR (r = 0.73, p < 0.0001). The area under the curve of pre-TAVR µQFR on post-TAVR FFR ≤ 0.8 was 0.91 (95% confidence interval [CI] 0.77-0.98), comparable to that of pre-TAVR iFR (0.86 [95% CI 0.71-0.98], p = 0.97). The accuracy, sensitivity, specificity, and positive and negative predictive values of pre-TAVR µQFR on post-TAVR FFR ≤ 0.8 were 84.2% (95% CI 68.7-93.4), 61.6% (95% CI 31.6-86.1), 96.0% (95% CI 79.6-99.9), 88.9% (95% CI 52.9-98.3), and 82.8% (95% CI 70.6-90.6), respectively. For pre-TAVR iFR, these values were 76.5% (95% CI 58.8-89.3), 90.9% (95% CI 58.7-99.8), 69.6% (95% CI 47.1-86.8), 58.8% (95% CI 42.8-73.1), and 94.1% (95% CI 70.8-99.1), respectively. CONCLUSION: µQFR could be useful for the physiological evaluation of patients with severe AS with concomitant CAD.


Subject(s)
Aortic Valve Stenosis , Aortic Valve , Coronary Angiography , Fractional Flow Reserve, Myocardial , Severity of Illness Index , Transcatheter Aortic Valve Replacement , Humans , Aortic Valve Stenosis/surgery , Aortic Valve Stenosis/physiopathology , Aortic Valve Stenosis/diagnosis , Male , Female , Fractional Flow Reserve, Myocardial/physiology , Aged, 80 and over , Aged , Aortic Valve/surgery , Aortic Valve/physiopathology , Aortic Valve/diagnostic imaging , Retrospective Studies , Reproducibility of Results , Predictive Value of Tests , Coronary Vessels/physiopathology , Coronary Vessels/diagnostic imaging , Coronary Artery Disease/diagnosis , Coronary Artery Disease/physiopathology , Coronary Artery Disease/surgery
9.
Clin Exp Nephrol ; 28(8): 764-772, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38530491

ABSTRACT

BACKGROUND: We investigate whether Intensive uric acid (UA)-lowering therapy (ULT) provides increased renal protection compared with standard therapy in chronic kidney disease (CKD) patients. METHODS: This was a multicenter randomized controlled trial. Only CKD patients with hyperuricemia were included in this study. The participants were randomly assigned to either the Intensive therapy group (target serum UA level ≥ 4.0 mg/dL and < 5.0 mg/dL) or the standard therapy group (serum UA level ≥ 6.0 mg/dL and < 7.0 mg/dL). ULT was performed using topiroxostat, a non-purine-type selective xanthine oxidase inhibitor. The primary endpoint was change in the logarithmic value of urine albumin to the creatinine ratio (ACR) between baseline and week 52 of the treatment. RESULTS: Three hundred fifty-two patients were included in the full analysis set. In the Standard therapy group, mean serum UA was 8.23 mg/dL at baseline and 6.13 mg/dL at 52 weeks. In the Intensive therapy group, mean serum UA was 8.15 mg/dL at baseline and 5.25 mg/dL at 52 weeks. There was no significant difference in changes in log ACR at 52 weeks between the Intensive therapy and the Standard therapy groups. CONCLUSION: This study did not reveal the benefit of Intensive ULT to improve albuminuria levels. (UMIN000026741 and jRCTs051180146).


Subject(s)
Albuminuria , Hyperuricemia , Renal Insufficiency, Chronic , Uric Acid , Humans , Hyperuricemia/drug therapy , Hyperuricemia/complications , Hyperuricemia/blood , Male , Female , Middle Aged , Renal Insufficiency, Chronic/complications , Renal Insufficiency, Chronic/drug therapy , Uric Acid/blood , Aged , Albuminuria/drug therapy , Creatinine/blood , Creatinine/urine , Treatment Outcome , Xanthine Oxidase/antagonists & inhibitors , Nitriles/therapeutic use , Biomarkers/blood , Biomarkers/urine , Pyridines
10.
Graefes Arch Clin Exp Ophthalmol ; 262(8): 2579-2591, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38430227

ABSTRACT

PURPOSE: To evaluate the long-term efficacy and safety of ripasudil-brimonidine fixed-dose combination (RBFC), a new intraocular pressure (IOP)-lowering medication for glaucoma and ocular hypertension (OHT). METHODS: This prospective, multicentre (23 sites in Japan), open-label study enrolled patients with primary open-angle glaucoma (POAG), OHT or exfoliative glaucoma and assigned them to one of four combination therapy cohorts, based on previous treatment(s) received: prostaglandin (PG) analogue (Cohort 1); PG analogue and beta-adrenoceptor blocker (ß-blocker) (Cohort 2); PG analogue, ß-blocker and carbonic anhydrase inhibitor (Cohort 3); or other/no treatment (Cohort 4). After a ≥ 4-week screening period, eligible patients received twice-daily RBFC for 52 weeks in addition to the treatments they were already receiving. Efficacy was assessed by change in IOP from baseline through week 52. Adverse events and adverse drug reactions (ADRs) were monitored throughout. RESULTS: In total, 179 patients from Cohort 1 (n = 48), Cohort 2 (n = 44), Cohort 3 (n = 41) and Cohort 4 (n = 46) entered the RBFC treatment period. For all cohorts, mean IOP was significantly reduced at 11:00 (2 h after instillation of RBFC) through week 52 with the changes from baseline at week 52 of - 2.7 to - 4.1 mmHg across cohorts; all p < 0.001. Common ADRs were conjunctival hyperaemia (58%), allergic conjunctivitis (18%) and blepharitis (17%), most of which were mild in severity. CONCLUSION: These data demonstrated the long-term efficacy and safety of RBFC, both alone and in combination with other anti-glaucoma agents. RBFC may offer a new treatment option for the long-term management of glaucoma and OHT. TRIAL REGISTRATION: Japan Registry of Clinical Trials Identifier: jRCT2080225063. DATE OF REGISTRATION: 17 February 2020.


Subject(s)
Antihypertensive Agents , Brimonidine Tartrate , Intraocular Pressure , Isoquinolines , Ocular Hypertension , Sulfonamides , Humans , Intraocular Pressure/drug effects , Intraocular Pressure/physiology , Ocular Hypertension/drug therapy , Ocular Hypertension/physiopathology , Ocular Hypertension/diagnosis , Male , Female , Prospective Studies , Aged , Sulfonamides/administration & dosage , Sulfonamides/adverse effects , Isoquinolines/administration & dosage , Isoquinolines/adverse effects , Brimonidine Tartrate/administration & dosage , Treatment Outcome , Middle Aged , Antihypertensive Agents/administration & dosage , Antihypertensive Agents/adverse effects , Follow-Up Studies , Ophthalmic Solutions , Time Factors , Dose-Response Relationship, Drug , Tonometry, Ocular , Drug Combinations , Glaucoma, Open-Angle/drug therapy , Glaucoma, Open-Angle/physiopathology
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