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1.
Biophys J ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459696

RESUMO

ATP synthase, a crucial enzyme for cellular bioenergetics, operates via the coordinated coupling of an FO motor, which presents variable symmetry, and a tripartite F1 motor. Despite extensive research, the understanding of their coupling dynamics, especially with non-10-fold symmetrical FO motors, remains incomplete. This study investigates the coupling patterns between eightfold and ninefold FO motors and the constant threefold F1 motor using coarse-grained molecular dynamics simulations. We unveil that in the case of a ninefold FO motor, a 3-3-3 motion is most likely to occur, whereas a 3-3-2 motion predominates with an eightfold FO motor. Furthermore, our findings propose a revised model for the coupling method, elucidating that the pathways' energy usage is primarily influenced by F1 rotation and conformational changes hindered by the b-subunits. Our results present a crucial step toward comprehending the energy landscape and mechanisms governing ATP synthase operation.

2.
Sci Rep ; 14(1): 5541, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448511

RESUMO

StayGold is a bright fluorescent protein (FP) that is over one order of magnitude more photostable than any of the currently available FPs across the full range of illumination intensities used in widefield microscopy and structured illumination microscopy, the latter of which is a widefield illumination-based technique. To compare the photostability of StayGold under other illumination modes with that of three other green-emitting FPs, namely EGFP, mClover3, and mNeonGreen, we expressed all four FPs as fusions to histone 2B in HeLa cells. Unlike the case of widefield microscopy, the photobleaching behavior of these FPs in laser scanning confocal microscopy (LSCM) is complicated. The outstanding photostability of StayGold observed in multi-beam LSCM was variably attenuated in single-beam LSCM, which produces intermittent and instantaneously strong illumination. We systematically examined the effects of different single-beam LSCM beam-scanning patterns on the photostability of the FPs in living HeLa cells. This study offers relevant guidelines for researchers who aim to achieve sustainable live cell imaging by resolving problems related to FP photostability. We also provide evidence for measurable sensitivity of the photostability of StayGold to chemical fixation.


Assuntos
Luz , Iluminação , Humanos , Células HeLa , Corantes , Microscopia Confocal
3.
Angew Chem Int Ed Engl ; 63(15): e202400711, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38315771

RESUMO

The development of near-infrared (NIR) fluorophores that have both excellent chemical stability and photostability, as well as efficient cell permeability, is highly demanded. In this study, we present phospha-rhodamine (POR) dyes which display significantly improved performance for protein labeling. This is achieved by incorporating a 2-carboxy-3-benzothiophenyl group at the 9-position of the xanthene scaffold. The resulting cis and trans isomers were successfully isolated and structurally characterized using X-ray diffraction. The HaloTag ligand conjugates of the two isomers exhibited different staining abilities in live cells. While the cis isomer showed non-specific accumulation on the organelle membranes, the trans isomer selectively labeled the HaloTag-fused proteins, enabling the long-term imaging of cell division and the 5-color imaging of cell organelles. Molecular dynamics simulations of the HaloTag ligand conjugates within the lipid membrane suggested that the cis isomer is more prone to forming oligomers in the membrane. In contrast, the oligomerization of the trans isomer is effectively suppressed by its interaction with the lipid molecules. By taking advantage of the superior labeling performance of the trans isomer and its NIR-emissive properties, multi-color time-lapse super-resolution 3D imaging, namely super-resolution 5D-imaging, of the interconnected network between the endoplasmic reticulum and microtubules was achieved in living cells.


Assuntos
Corantes Fluorescentes , Organelas , Rodaminas , Ligantes , Corantes Fluorescentes/química , Organelas/metabolismo , Proteínas , Microscopia de Fluorescência/métodos , Lipídeos
4.
Sci Rep ; 14(1): 2852, 2024 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310141

RESUMO

To develop artificial cell models that mimic living cells, cell-sized lipid vesicles encapsulating cell-free protein synthesis (CFPS) systems are useful for protein expressions or artificial gene circuits for vesicle-vesicle communications. Therefore, investigating the transcriptional and translational properties of CFPS systems in lipid vesicles is important for maximizing the synthesis and functions of proteins. Although transcription and translation using CFPS systems inside lipid vesicles are more important than that outside lipid vesicles, the former processes are not investigated by changing the lipid composition of lipid vesicles. Herein, we investigated changes in transcription and translation using CFPS systems inside giant lipid vesicles (approximately 5-20 µm in diameter) caused by changing the lipid composition of lipid vesicles containing neutral, positively, and negatively charged lipids. After incubating for 30 min, 1 h, 2 h, and 4 h, the transcriptional and translational activities in these lipid vesicles were determined by detecting the fluorescence intensities of the fluorogenic RNA aptamer on the 3'-untranslated region of mRNA (transcription) and the fluorescent protein sfCherry (translation), respectively. The results revealed that transcriptional and translational activities in a lipid vesicle containing positively charged lipids were high when the protein was synthesized using the CFPS system inside the lipid vesicle. Thus, the present study provides an experimental basis for constructing complex artificial cell models using bottom-up approaches.


Assuntos
Lipídeos , Proteínas , Fluorescência
5.
EMBO J ; 43(4): 568-594, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38263333

RESUMO

Comprehensive analysis of cellular dynamics during the process of morphogenesis is fundamental to understanding the principles of animal development. Despite recent advancements in light microscopy, how successive cell shape changes lead to complex three-dimensional tissue morphogenesis is still largely unresolved. Using in vivo live imaging of Drosophila wing development, we have studied unique cellular structures comprising a microtubule-based membrane protrusion network. This network, which we name here the Interplanar Amida Network (IPAN), links the two wing epithelium leaflets. Initially, the IPAN sustains cell-cell contacts between the two layers of the wing epithelium through basal protrusions. Subsequent disassembly of the IPAN involves loss of these contacts, with concomitant degeneration of aligned microtubules. These processes are both autonomously and non-autonomously required for mitosis, leading to coordinated tissue proliferation between two wing epithelia. Our findings further reveal that a microtubule organization switch from non-centrosomal to centrosomal microtubule-organizing centers (MTOCs) at the G2/M transition leads to disassembly of non-centrosomal microtubule-derived IPAN protrusions. These findings exemplify how cell shape change-mediated loss of inter-tissue contacts results in 3D tissue morphogenesis.


Assuntos
Drosophila , Microtúbulos , Animais , Microtúbulos/metabolismo , Epitélio/metabolismo , Centro Organizador dos Microtúbulos/metabolismo , Morfogênese
6.
Ann Neurol ; 95(2): 338-346, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37807081

RESUMO

OBJECTIVE: Atrial fibrillation (AF) detected after insular stroke might arise from autonomic and inflammatory mechanisms triggered by insular damage, and be associated with a low embolic risk. We assessed the association of the timing of AF detection and insular involvement with the risk of embolic events after acute ischemic stroke. METHODS: Acute ischemic stroke patients with AF who underwent brain magnetic resonance imaging at baseline were enrolled. Patients were classified according to the timing of AF detection (AF detected after stroke [AFDAS] or known AF [KAF]) and insular involvement. The primary outcome was embolic events defined as recurrent ischemic stroke, transient ischemic attack, and systemic embolism within 90 days. RESULTS: Of 1,548 patients, 360 had AFDAS with insular cortex lesions (+I), 409 had AFDAS without insular cortex lesions (-I), 349 had KAF+I, and 430 had KAF-I. Cumulative incidence rates of embolic events at 90 days in patients with AFDAS+I, AFDAS-I, KAF+I, and KAF-I were 0.8%, 3.5%, 4.9%, and 3.3%, respectively. Patients with AFDAS-I (adjusted hazard ratio 5.04, 95% confidence interval 1.43-17.75), KAF+I (6.18, 1.78-21.46), and KAF-I (5.26, 1.48-18.69) had a significantly higher risk of embolic events than those with AFDAS+I. INTERPRETATION: Acute ischemic stroke patients with AFDAS and insular cortex lesions had a lower risk of embolic events than those who had AFDAS without insular cortex lesions or those with KAF, regardless of insular involvement. ANN NEUROL 2024;95:338-346.


Assuntos
Fibrilação Atrial , Isquemia Encefálica , Embolia , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , AVC Isquêmico/complicações , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia , Embolia/complicações , Embolia/diagnóstico por imagem , Fatores de Risco
7.
Ann Neurol ; 95(4): 774-787, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38146238

RESUMO

OBJECTIVE: This study was undertaken to determine the excess risk of antithrombotic-related bleeding due to cerebral small vessel disease (SVD) burden. METHODS: In this observational, prospective cohort study, patients with cerebrovascular or cardiovascular diseases taking oral antithrombotic agents were enrolled from 52 hospitals across Japan between 2016 and 2019. Baseline multimodal magnetic resonance imaging acquired under prespecified conditions was assessed by a central diagnostic radiology committee to calculate total SVD score. The primary outcome was major bleeding. Secondary outcomes included bleeding at each site and ischemic events. RESULTS: Of the analyzed 5,250 patients (1,736 women; median age = 73 years, 9,933 patient-years of follow-up), antiplatelets and anticoagulants were administered at baseline in 3,948 and 1,565, respectively. Median SVD score was 2 (interquartile range = 1-3). Incidence rate of major bleeding was 0.39 (per 100 patinet-years) in score 0, 0.56 in score 1, 0.91 in score 2, 1.35 in score 3, and 2.24 in score 4 (adjusted hazard ratio [aHR] for score 4 vs 0 = 5.47, 95% confidence interval [CI] = 2.26-13.23), that of intracranial hemorrhage was 0.11, 0.33, 0.58, 0.99, and 1.06, respectively (aHR = 9.29, 95% CI = 1.99-43.35), and that of ischemic event was 1.82, 2.27, 3.04, 3.91, and 4.07, respectively (aHR = 1.76, 95% CI = 1.08-2.86). In addition, extracranial major bleeding (aHR = 3.43, 95% CI = 1.13-10.38) and gastrointestinal bleeding (aHR = 2.54, 95% CI = 1.02-6.35) significantly increased in SVD score 4 compared to score 0. INTERPRETATION: Total SVD score was predictive for intracranial hemorrhage and probably for extracranial bleeding, suggesting the broader clinical relevance of cerebral SVD as a marker for safe implementation of antithrombotic therapy. ANN NEUROL 2024;95:774-787.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Acidente Vascular Cerebral , Humanos , Feminino , Idoso , Fibrinolíticos/efeitos adversos , Estudos Prospectivos , Hemorragia , Doenças de Pequenos Vasos Cerebrais/epidemiologia , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/epidemiologia , Anticoagulantes , Acidente Vascular Cerebral/epidemiologia
8.
Nat Methods ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036853

RESUMO

Although StayGold is a bright and highly photostable fluorescent protein, its propensity for obligate dimer formation may hinder applications in molecular fusion and membrane targeting. To attain monovalent as well as bright and photostable labeling, we engineered tandem dimers of StayGold to promote dispersibility. On the basis of the crystal structure of this fluorescent protein, we disrupted the dimerization to generate a monomeric variant that offers improved photostability and brightness compared to StayGold. We applied the new monovalent StayGold tools to live-cell imaging experiments using spinning-disk laser-scanning confocal microscopy or structured illumination microscopy. We achieved cell-wide, high-spatiotemporal resolution and sustained imaging of dynamic subcellular events, including the targeting of endogenous condensin I to mitotic chromosomes, the movement of the Golgi apparatus and its membranous derivatives along microtubule networks, the distribution of cortical filamentous actin and the remolding of cristae membranes within mobile mitochondria.

9.
Nat Mater ; 22(12): 1564-1570, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37903925

RESUMO

Cosmic large-scale structures, animal flocks and living tissues can be considered non-equilibrium organized systems created by dissipative processes. Replicating such properties in artificial systems is still difficult. Herein we report a dissipative network formation process in a dilute polymer-water mixture that leads to percolation-induced gel-gel phase separation. The dilute system, which forms a monophase structure at the percolation threshold, spontaneously separates into two co-continuous gel phases with a submillimetre scale (a dilute-percolated gel) during the deswelling process after the completion of the gelation reaction. The dilute-percolated gel, which contains 99% water, exhibits unexpected hydrophobicity and induces the development of adipose-like tissues in subcutaneous tissues. These findings support the development of dissipative structures with advanced functionalities for distinct applications, ranging from physical chemistry to tissue engineering.


Assuntos
Polímeros , Animais , Géis/química , Polímeros/química , Interações Hidrofóbicas e Hidrofílicas , Água/química
10.
BMJ Open ; 13(9): e073708, 2023 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723115

RESUMO

INTRODUCTION: Soluble C-type lectin-like receptor 2 (sCLEC-2) is a new biomarker for platelet activation, which can be easily measured by usual blood collection. We conducted the CLECSTRO, a prospective, observational cohort study, to evaluate the clinical implications of sCLEC-2 in patients with acute ischaemic stroke (AIS) and transient ischaemic attack (TIA). METHODS AND ANALYSIS: The participants are patients with AIS/TIA and control patients required for differentiation from AIS/TIA. The target population is 600, including the patients and controls, who would be recruited from eight stroke centres across Japan. The inclusion criteria are AIS within 24 hours of onset and a modified Rankin Scale (mRS) score of 0-2, TIA within 7 days of onset, and contemporary patients required for differentiation from AIS/TIA. Plasma sCLEC-2 will be measured by high-sensitive chemiluminescent enzyme immunoassay using residual blood samples from routine laboratory examinations at the first visit in all patients and 7 days later or at discharge in patients with AIS/TIA. The outcomes include plasma levels of sCLEC-2 in patients with AIS/TIA and controls, sCLEC-2/D-dimer ratio in non-cardioembolic and cardioembolic AIS/TIA, correlation of sCLEC-2 with recurrence or worsening of stroke, severity of stroke, infarct size, ABCD2 score in TIA and outcome (mRS) at 7 days and 3 months. ETHICS AND DISSEMINATION: This study was approved by the Ethical Committee of the University of Yamanashi as the central ethical committee in agreement with the ethical committees of all collaborative stroke centres. Informed consent will be obtained by an opt-out form from the patients at each stroke centre according to the Ethical Guidelines for Medical and Biological Research Involving Human Subjects by the Japanese Ministry of Health, Labour and Welfare. TRIAL REGISTRATION NUMBERS: NCT05579405, UMIN000048954.


Assuntos
Isquemia Encefálica , Ataque Isquêmico Transitório , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/diagnóstico , Ataque Isquêmico Transitório/diagnóstico , Lectinas Tipo C , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico
11.
EMBO J ; 42(18): e112305, 2023 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-37609947

RESUMO

Nanog and Oct4 are core transcription factors that form part of a gene regulatory network to regulate hundreds of target genes for pluripotency maintenance in mouse embryonic stem cells (ESCs). To understand their function in the pluripotency maintenance, we visualised and quantified the dynamics of single molecules of Nanog and Oct4 in a mouse ESCs during pluripotency loss. Interestingly, Nanog interacted longer with its target loci upon reduced expression or at the onset of differentiation, suggesting a feedback mechanism to maintain the pluripotent state. The expression level and interaction time of Nanog and Oct4 correlate with their fluctuation and interaction frequency, respectively, which in turn depend on the ESC differentiation status. The DNA viscoelasticity near the Oct4 target locus remained flexible during differentiation, supporting its role either in chromatin opening or a preferred binding to uncondensed chromatin regions. Based on these results, we propose a new negative feedback mechanism for pluripotency maintenance via the DNA condensation state-dependent interplay of Nanog and Oct4.


Assuntos
Células-Tronco Embrionárias Murinas , Imagem Individual de Molécula , Animais , Camundongos , Retroalimentação , Cromatina/genética , Diferenciação Celular
12.
Bio Protoc ; 13(14): e4715, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37497447

RESUMO

Immotile cilia of crown cells at the node of mouse embryos are required for sensing leftward fluid flow that gives rise to the breaking of left-right (L-R) symmetry. The flow-sensing mechanism has long remained elusive, mainly because of difficulties inherent in manipulating and precisely analyzing the cilium. Recent progress in optical microscopy and biophysical analysis has allowed us to study the mechanical signals involving primary cilia. In this study, we used high-resolution imaging with mechanical modeling to assess the membrane tension in a single cilium. Optical tweezers, a technique used to trap sub-micron-sized particles with a highly focused laser beam, allowed us to manipulate individual cilia. Super-resolution microscopy allowed us to discern the precise localization of ciliary proteins. Using this protocol, we provide a method for applying these techniques to cilia in mouse embryonic nodes. This method is widely applicable to the determination of mechanical signals in other cilia.

13.
Mol Cell ; 83(12): 2045-2058.e9, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37192628

RESUMO

Mitophagy plays an important role in mitochondrial homeostasis by selective degradation of mitochondria. During mitophagy, mitochondria should be fragmented to allow engulfment within autophagosomes, whose capacity is exceeded by the typical mitochondria mass. However, the known mitochondrial fission factors, dynamin-related proteins Dnm1 in yeasts and DNM1L/Drp1 in mammals, are dispensable for mitophagy. Here, we identify Atg44 as a mitochondrial fission factor that is essential for mitophagy in yeasts, and we therefore term Atg44 and its orthologous proteins mitofissin. In mitofissin-deficient cells, a part of the mitochondria is recognized by the mitophagy machinery as cargo but cannot be enwrapped by the autophagosome precursor, the phagophore, due to a lack of mitochondrial fission. Furthermore, we show that mitofissin directly binds to lipid membranes and brings about lipid membrane fragility to facilitate membrane fission. Taken together, we propose that mitofissin acts directly on lipid membranes to drive mitochondrial fission required for mitophagy.


Assuntos
Autofagia , Mitofagia , Animais , Dinâmica Mitocondrial , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Dinaminas/genética , Dinaminas/metabolismo , Lipídeos , Mamíferos/metabolismo
14.
Nucleic Acids Res ; 51(12): 6190-6207, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37178005

RESUMO

Heterochromatin is a key architectural feature of eukaryotic chromosomes critical for cell type-specific gene expression and genome stability. In the mammalian nucleus, heterochromatin segregates from transcriptionally active genomic regions and exists in large, condensed, and inactive nuclear compartments. However, the mechanisms underlying the spatial organization of heterochromatin need to be better understood. Histone H3 lysine 9 trimethylation (H3K9me3) and lysine 27 trimethylation (H3K27me3) are two major epigenetic modifications that enrich constitutive and facultative heterochromatin, respectively. Mammals have at least five H3K9 methyltransferases (SUV39H1, SUV39H2, SETDB1, G9a and GLP) and two H3K27 methyltransferases (EZH1 and EZH2). In this study, we addressed the role of H3K9 and H3K27 methylation in heterochromatin organization using a combination of mutant cells for five H3K9 methyltransferases and an EZH1/2 dual inhibitor, DS3201. We showed that H3K27me3, which is normally segregated from H3K9me3, was redistributed to regions targeted by H3K9me3 after the loss of H3K9 methylation and that the loss of both H3K9 and H3K27 methylation resulted in impaired condensation and spatial organization of heterochromatin. Our data demonstrate that the H3K27me3 pathway safeguards heterochromatin organization after the loss of H3K9 methylation in mammalian cells.


Assuntos
Epigênese Genética , Heterocromatina , Animais , Heterocromatina/genética , Histonas/metabolismo , Lisina/metabolismo , Mamíferos/genética , Metilação , Histona Metiltransferases/metabolismo
15.
Sci Adv ; 9(14): eadf1488, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37018405

RESUMO

In eukaryotes, higher-order chromatin organization is spatiotemporally regulated as domains, for various cellular functions. However, their physical nature in living cells remains unclear (e.g., condensed domains or extended fiber loops; liquid-like or solid-like). Using novel approaches combining genomics, single-nucleosome imaging, and computational modeling, we investigated the physical organization and behavior of early DNA replicated regions in human cells, which correspond to Hi-C contact domains with active chromatin marks. Motion correlation analysis of two neighbor nucleosomes shows that nucleosomes form physically condensed domains with ~150-nm diameters, even in active chromatin regions. The mean-square displacement analysis between two neighbor nucleosomes demonstrates that nucleosomes behave like a liquid in the condensed domain on the ~150 nm/~0.5 s spatiotemporal scale, which facilitates chromatin accessibility. Beyond the micrometers/minutes scale, chromatin seems solid-like, which may contribute to maintaining genome integrity. Our study reveals the viscoelastic principle of the chromatin polymer; chromatin is locally dynamic and reactive but globally stable.


Assuntos
Cromatina , Nucleossomos , Humanos , DNA , Eucariotos , Montagem e Desmontagem da Cromatina
16.
J Stroke Cerebrovasc Dis ; 32(6): 107087, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36972640

RESUMO

A 63-year-old man was admitted to our stroke center with brain infarction in the left posterior inferior cerebellar artery (PICA) territory. The initial MRI showed no findings suggestive of arterial dissection, and post-discharge MRI showed no temporal changes. Digital subtraction angiography (DSA) revealed vasodilation of the proximal portion of the PICA but it was uncertain whether dissection was present. Discrepancy between the outer contour seen on constructive interference in steady state (CISS) MRI and the inner contour seen on DSA suggested the presence of intramural hematoma. The patient was diagnosed with brain infarction caused by isolated PICA dissection (iPICAD). Imaging evaluation of combined CISS and DSA may be particularly useful for identification of small iPICAD lesions.


Assuntos
Assistência ao Convalescente , Alta do Paciente , Masculino , Humanos , Pessoa de Meia-Idade , Angiografia Digital , Artéria Vertebral/patologia , Infarto Encefálico/patologia , Cerebelo/irrigação sanguínea
17.
Stroke ; 54(3): 697-705, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36734235

RESUMO

BACKGROUND: The effectiveness of long-term dual antiplatelet therapy (DAPT) to prevent recurrent strokes in patients with lacunar stroke remains unclarified. Therefore, this study aimed to compare and to elucidate the safety and effectiveness of DAPT and single antiplatelet therapy (SAPT) in preventing recurrence in chronic lacunar stroke. METHODS: CSPS.com (Cilostazol Stroke Prevention Study for Antiplatelet Combination) was a prospective, multicenter, randomized controlled trial. In this prespecified subanalysis, 925 patients (mean age, 69.5 years; 69.4% men) with lacunar stroke were selected from 1884 patients with high-risk noncardioembolic stroke, enrolled in the CSPS.com trial after 8 to 180 days following stroke. Patients were randomly assigned to receive either SAPT or DAPT using cilostazol and were followed for 0.5 to 3.5 years. The primary efficacy outcome was the first recurrence of ischemic stroke. The safety outcomes were severe or life-threatening bleeding. RESULTS: The DAPT group receiving cilostazol and either aspirin or clopidogrel and SAPT group receiving aspirin or clopidogrel alone comprised 464 (50.2%) and 461 (49.8%) patients, respectively. Ischemic stroke occurred in 12 of 464 patients (1.84 per 100 patient-years) in the DAPT group and 31 of 461 patients (4.42 per 100 patient-years) in the SAPT group, during follow-up. After adjusting for multiple potential confounding factors, ischemic stroke risk was significantly lower in the DAPT group than in the SAPT group (hazard ratio, 0.43 [95% CI, 0.22-0.84]). The rate of severe or life-threatening hemorrhage did not differ significantly between the groups (2 patients [0.31 per 100 patient-years] versus 6 patients [0.86 per 100 patient-years] in the DAPT and SAPT groups, respectively; hazard ratio, 0.36 [95% CI, 0.07-1.81]). CONCLUSIONS: In patients with lacunar stroke, DAPT using cilostazol had significant benefits in reducing recurrent ischemic stroke incidence compared with SAPT without increasing the risk of severe or life-threatening bleeding. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01995370. URL: https://www.umin.ac.jp/ctr; Unique identifier: UMIN000012180.


Assuntos
Acidente Vascular Cerebral Lacunar , Acidente Vascular Cerebral , Masculino , Humanos , Idoso , Feminino , Inibidores da Agregação Plaquetária/efeitos adversos , Cilostazol/uso terapêutico , Clopidogrel/uso terapêutico , Prevenção Secundária , Acidente Vascular Cerebral Lacunar/tratamento farmacológico , Acidente Vascular Cerebral Lacunar/epidemiologia , Acidente Vascular Cerebral Lacunar/prevenção & controle , Estudos Prospectivos , Quimioterapia Combinada , Aspirina/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Hemorragia/induzido quimicamente
18.
Science ; 379(6627): 66-71, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36603091

RESUMO

Immotile cilia at the ventral node of mouse embryos are required for sensing leftward fluid flow that breaks left-right symmetry of the body. However, the flow-sensing mechanism has long remained elusive. In this work, we show that immotile cilia at the node undergo asymmetric deformation along the dorsoventral axis in response to the flow. Application of mechanical stimuli to immotile cilia by optical tweezers induced calcium ion transients and degradation of Dand5 messenger RNA (mRNA) in the targeted cells. The Pkd2 channel protein was preferentially localized to the dorsal side of immotile cilia, and calcium ion transients were preferentially induced by mechanical stimuli directed toward the ventral side. Our results uncover the biophysical mechanism by which immotile cilia at the node sense the direction of fluid flow.


Assuntos
Sinalização do Cálcio , Cálcio , Cílios , Mecanotransdução Celular , Animais , Camundongos , Cálcio/metabolismo , Cílios/fisiologia , Embrião de Mamíferos
19.
Intern Med ; 62(8): 1223-1225, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36104189

RESUMO

Extracranial vertebral artery dissection is a cerebrovascular disease that occurs most commonly in young people. A 32-year-old man experienced sudden cervical pain and was diagnosed with left vertebral artery dissection after arterial changes were identified by ultrasonography. The reduction in the size of an intramural hematoma in the left vertebral artery and in the peak systolic velocity were evaluated over time. Computed tomography, magnetic resonance imaging, and cerebral angiography are generally performed to diagnose and follow-up extracranial vertebral artery dissection; however, carotid ultrasonography has an advantage over these modalities by enabling the simultaneous observation of vascular morphology and hemodynamics.


Assuntos
Dissecação da Artéria Vertebral , Masculino , Humanos , Adolescente , Adulto , Dissecação da Artéria Vertebral/diagnóstico por imagem , Seguimentos , Ultrassonografia/métodos , Artéria Vertebral/diagnóstico por imagem , Imageamento por Ressonância Magnética , Angiografia por Ressonância Magnética
20.
Jpn J Radiol ; 41(2): 219-227, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36121624

RESUMO

PURPOSE: False-negative findings in radiological reports can lead to serious adverse patient outcomes. We determined the frequency and tendency of false-negative findings in radiological reports by searching for words related to "visible in retrospect". METHODS: In the period of 34 months, we extracted radiological reports containing words related to "visible in retrospect". Of these reports, we extracted false-negative findings that were not described in past reports and were first detected retrospectively. Misinterpretations were excluded. The occurrences of the terms that we identified were analyzed by all examinations, modality, month, and anatomical and lesion classifications were analyzed. RESULTS: Of the 135,251 examinations, 941 reports (0.71%) with 962 findings were detected, with an average of 1.4 findings per business day. By modality, 713 of 81,899 (0.87%) CT examinations, 208 of 36,174 (0.57%) MR, 34 of 9,585 (0.35%) FDG-PET-CT, 2 of 2,258 (0.09%) digital radiography, and 5 of 5,335 (0.09%) other nuclear medicine examinations were found. By anatomical classification, there were 383 (40%) in chest, 353 (37%) in abdomen, 162 (17%) in head, 42 (4.4%) in face and neck, 9 (0.93%) in extremity, and 13 (1.4%) in others. By lesion classification, we identified 665 (69%) for localized lesion, 170 (18%) for vascular lesion, 83 (8.6%) for inflammatory lesion, 14 (1.5%) for traumatic lesion, 12 (1.2%) for organ dysfunction, 11 (1.1%) for degenerative lesion, and 7 (0.7%) for the others. Notable high-frequency specific site diseases by modality were 210 (22%) of localized lesions in lung on CT. CONCLUSION: Our results demonstrated that missed lung localized lesions on CT, which account for about a fifth of false-negative findings, were the most common false-negative finding.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia Computadorizada por Raios X , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Tomografia por Emissão de Pósitrons , Cintilografia , Fluordesoxiglucose F18 , Compostos Radiofarmacêuticos
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