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1.
Small ; 20(13): e2306154, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37967353

RESUMO

Hierarchical superstructures have novel shape-dependent properties, but well-defined anisotropic carbon superstructures with controllable size, shape, and building block dimensionality have rarely been accomplished thus far. Here, a hierarchical assembly technique is presented that uses spinodal decomposition (SD) to synthesize anisotropic oblate particles of mesoporous carbon superstructure (o-MCS) with nanorod arrays by integrating block-copolymer (BCP) self-assembly and polymer-polymer interface behaviors in binary blends. The interaction of major and minor phases in binary polymer blends leads to the formation of an anisotropic oblate particle, and the BCP-rich phase enables ordered packing and unidirectional alignment of carbon nanorods. Consequently, this approach enables precise control over particles' size, shape, and over the dimensionality of their components. Exploiting this functional superstructure, o-MCS are used as an anode material in potassium-ion batteries, and achieve a notable specific capacity of 156 mA h g-1 at a current density of 2 A g-1, and long-term stability for 3000 cycles. This work presents a significant advancement in the field of hierarchical superstructures, providing a promising strategy for the design and synthesis of anisotropic carbon materials with controlled properties, offering promising applications in energy storage and beyond.

2.
J Electrocardiol ; 79: 46-52, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36934492

RESUMO

BACKGROUND: Ventricular tachyarrhythmia is a potentially fatal outcome of cardiac surgery. Abrupt changes in the hemodynamics after surgical correction of valvular heart disease (VHD) can lead to alterations in ventricular repolarization. We compared the difference between temporal changes in repolarization parameters after correction of left-sided VHD. METHODS: We retrospectively analyzed the electrograms of patients who underwent surgical correction of isolated VHD between 2006 and 2015 at Asan Medical Center, including mitral stenosis (MS), mitral regurgitation (MR), aortic stenosis (AS), and aortic regurgitation (AR). Ventricular repolarization parameters were measured at pre-specified time intervals after index surgery using a custom-made ECG analysis program. We compared repolarization parameters, including QT and corrected QT intervals, T peak-to-end interval, and corrected T peak-to-end interval. RESULTS: Analysis of 8265 ECGs from 2110 patients (266 MS, 1059 MR, 421 AS, and 364 AR) was performed. Patients with AS were characterized by older age and more comorbidities than other VHDs. The corrected QT interval showed a peak value immediately after surgery and decreased thereafter in the AS groups. However, a gradual increase over 1 month after surgery in AR, MS, and MR groups was observed. The corrected T peak-to-end interval increased in the MS and MR groups and was unchanged in the AS and AR groups. CONCLUSIONS: The repolarization parameters of surgery changed dynamically after left-sided valvular surgery. Understanding differential temporal change of repolarization parameters according to the type of VHD would help clinicians avoid fatal arrhythmias related to the repolarization changes.


Assuntos
Estenose da Valva Aórtica , Doenças das Valvas Cardíacas , Insuficiência da Valva Mitral , Humanos , Eletrocardiografia , Estudos Retrospectivos , Arritmias Cardíacas/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Comorbidade , Insuficiência da Valva Mitral/cirurgia
3.
J Am Chem Soc ; 143(38): 15644-15652, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34469682

RESUMO

Two-dimensional (2D) porous inorganic nanomaterials have intriguing properties as a result of dimensional features and high porosity, but controlled production of circular 2D shapes is still challenging. Here, we designed a simple approach to produce 2D porous inorganic nanocoins (NCs) by integrating block copolymer (BCP) self-assembly and orientation control of microdomains at polymer-polymer interfaces. Multicomponent blends containing BCP and homopoly(methyl methacrylate) (hPMMA) are designed to undergo macrophase separation followed by microphase separation. The balanced interfacial compatibility of BCP allows perpendicularly oriented lamellar-assembly at the interfaces between BCP-rich phase and hPMMA matrix. Disassembly of lamellar structures and calcination yield ultrathin 2D inorganic NCs that are perforated by micropores. This approach enables control of the thickness, size, and chemical composition of the NCs. 2D porous and acidic aluminosilicate NC (AS-NC) is used to fabricate an ultrathin and lightweight functional separator for lithium-sulfur batteries. The AS-NC layer acts as an ionic sieve to selectively block lithium polysulfides. Abundant acid sites chemically capture polysulfides, and micropores physically exclude them, so sulfur utilization and cycle stability are increased.

4.
Nanotechnology ; 32(27)2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33740775

RESUMO

In this study, we investigated the effect of an Al2O3barrier layer in an all-solid-state inorganic Li-based nano-ionic synaptic transistor (LST) with Li3PO4electrolyte/WOxchannel structure. Near-ideal synaptic behavior in the ultralow conductance range (∼50 nS) was obtained by controlling the abrupt ion migration through the introduction of a sputter-deposited thin (∼3 nm) Al2O3interfacial layer. A trade-off relationship between the weight update linearity and on/off ratio with varying Al2O3layer thickness was also observed. To determine the origin of the Al2O3barrier layer effects, cyclic voltammetry analysis was conducted, and the optimal ionic diffusivity and mobility were found to be key parameters in achieving ideal synaptic behavior. Owing to the controlled ion migration, the retention characteristics were considerably improved by the Al2O3barrier. Finally, a highly improved pattern recognition accuracy (83.13%) was achieved using the LST with an Al2O3barrier of optimal thickness.

5.
J Geriatr Psychiatry Neurol ; 34(6): 565-573, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-32912058

RESUMO

OBJECTIVE: The efficacy of antidepressants in post-stroke depressive symptoms (PSD) varies. We aimed to examine whether the effect of escitalopram on PSD differs according to individual depressive symptoms and stroke lesion location. METHODS: This is a post hoc analysis of EMOTION (ClinicalTrials.gov, NCT01278498), a randomized, placebo-controlled, double-blind trial that examined the efficacy of escitalopram on depression in acute stroke patients (237 with placebo, 241 with escitalopram). Depressive symptoms were evaluated with the 10-item Montgomery-Åsberg Depression Rating Scale (MADRS). Changes in MADRS and individual item scores at 12 weeks were compared between the treatment groups and among the stroke lesion location groups. Stroke lesion locations were grouped according to the anatomical distribution of serotonin fibers that originate from the midbrain/pons and spread to the forebrain via subcortical structures: "Midbrain-Pons," "Frontal-Subcortical," and "Others." Least-squares means were calculated to demonstrate the independent effect of lesion location. RESULTS: Total MADRS scores decreased more significantly in the escitalopram than in the placebo group, while a significant effect of escitalopram was observed in only 3 items: apparent sadness, reported sadness, pessimistic thoughts. In the lesion location analyses, escitalopram users in the Frontal-Subcortical group showed significant improvement in total MADRS scores (placebo [n = 130] vs. escitalopram [n = 148], least-square mean [95% CI]: -2.3 [-3.5 to -0.2] vs. -4.5 [-5.5 to -3.4], p = .005), while those in the Midbrain-Pons and Others groups did not. CONCLUSIONS: The effect of escitalopram on PSD may be more prominent in patients with particular depressive symptoms and stroke lesion locations, suggesting the need for tailored treatment strategies.


Assuntos
Transtorno Depressivo Maior , Acidente Vascular Cerebral , Citalopram/uso terapêutico , Depressão/tratamento farmacológico , Depressão/etiologia , Método Duplo-Cego , Escitalopram , Humanos , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do Tratamento
6.
Medicina (Kaunas) ; 57(9)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34577833

RESUMO

Background and Objectives: Cerebral aneurysms can cause disability or death during rupture, but information on the etiology of cerebral aneurysms is currently lacking. Periodontal disease causes both systemic inflammation and local inflammation of the oral cavity. Systemic inflammation is a major cause of cerebral aneurysms. The aim of our study was to determine whether the presence of periodontal disease is related to the occurrence of unruptured cerebral aneurysms in a nationwide population-based cohort. Materials and Methods: We analyzed data on demographics, previous medical history, and laboratory test results of 209,620 participants from the Korean National Health Insurance System-Health Screening Cohort. The presence of periodontal disease and oral hygiene parameters, including the number of lost teeth, tooth brushing frequency per day, dental visits for any reason, and expert teeth scaling, were investigated. The occurrences of unruptured cerebral aneurysms (I67.1) were defined according to the International Statistical Classification of Diseases Related Health Problems-10. Results: The mean age of the participants was 53.7 ± 8.7 years, and 59.4% were male. Periodontal disease was found in 20.9% of the participants. A total of 2160 (1.0%) cases of unruptured cerebral aneurysms developed after 10.3 years of median follow up. In multivariate analysis, the presence of periodontal disease was significantly associated with an increased risk of unruptured cerebral aneurysms (hazard ratio: 1.21, 95% confidence interval: 1.09-1.34, p < 0.001). Conclusion: The presence of periodontal disease could be associated with the occurrence of unruptured cerebral aneurysms. It should be noted that when periodontal diseases are present, the risk of aneurysms is increased in the future.TRANSLATE with x EnglishArabicHebrewPolishBulgarianHindiPortugueseCatalanHmong DawRomanianChinese SimplifiedHungarianRussianChinese TraditionalIndonesianSlovakCzechItalianSlovenianDanishJapaneseSpanishDutchKlingonSwedishEnglishKoreanThaiEstonianLatvianTurkishFinnishLithuanianUkrainianFrenchMalayUrduGermanMalteseVietnameseGreekNorwegianWelshHaitian CreolePersian// TRANSLATE with COPY THE URL BELOW Back EMBED THE SNIPPET BELOW IN YOUR SITE Enable collaborative features and customize widget: Bing Webmaster PortalBack//.


Assuntos
Aneurisma Intracraniano , Doenças Periodontais , Adulto , Estudos de Coortes , Humanos , Aneurisma Intracraniano/epidemiologia , Masculino , Pessoa de Meia-Idade , Doenças Periodontais/complicações , Doenças Periodontais/epidemiologia , República da Coreia/epidemiologia , Escovação Dentária
7.
J Am Chem Soc ; 142(20): 9250-9257, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32053749

RESUMO

Two-dimensional (2D) carbon nanosheets with micro- and/or mesopores have attracted great attention due to unique physical and chemical properties, but well-defined nanoporous carbon nanosheets with tunable thickness and pore size have been rarely realized. Here, we develop a polymer-polymer interfacial self-assembly strategy to achieve hierarchically porous carbon nanosheets (HNCNSs) by integrating the migration behaviors of immiscible ternary polymers with block copolymer (BCP)-directed self-assembly. The balanced interfacial compatibility of BCP allows the migration of a BCP-rich phase to the interface between two immiscible homopolymer major phases (i.e., homopoly(methyl methacrylate) and homopolystyrene), where the BCP-rich phase spreads thinly to a thickness of a few nanometers to decrease the interfacial tension. BCP-directed coassembly with organic-inorganic precursors constructs an ordered mesostructure. Carbonization and chemical etching yield ultrathin HNCNSs with hierarchical micropores and mesopores. This approach enables facile control over the thickness (5.6-75 nm) and mesopore size (25-46 nm). As an anode material in a potassium ion battery, HNCNSs show high specific capacity (178 mA h g-1 at a current density of 1 A g-1) with excellent long-term stability (2000 cycles), by exploiting the advantages of the hierarchical pores and 2D nanosheet morphology (efficient ion/electron diffusion) and of the large interlayer spacing (stable ion insertion).

8.
Stroke ; 50(12): 3503-3511, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31607242

RESUMO

Background and Purpose- We performed a systematic review and meta-analysis to explore the efficacy and safety of cilostazol as a mono or combination (plus aspirin or clopidogrel) treatments compared to conventional single antiplatelet therapy (SAPT, mainly aspirin) for secondary stroke prevention. Methods- Randomized controlled trial studies were searched across multiple comprehensive databases (MEDLINE, EMBASE, and Cochrane) for review. The primary outcome was recurrent stroke comprising ischemic and hemorrhagic stroke. Secondary outcomes included ischemic stroke, hemorrhagic stroke, myocardial infarction, and composite outcomes. We performed an updated systematic review and meta-analysis of the identified reports, including 2 recently published randomized controlled trials. In addition, network meta-analysis was performed to compare the relative effects of mono versus combination cilostazol treatments. Results- Ten studies were included in this review, 5 of which were assigned to the cilostazol mono group (n=5429) and the other 5 to the combination group (n=2456). The relative risks of recurrent stroke, ischemic stroke, and composite outcomes with cilostazol mono as well as combination treatments were significantly lower than with SAPT without any significant heterogeneity. An indirect comparison of these 3 outcomes revealed the cilostazol combination approach to be superior. The cilostazol mono treatment diminished hemorrhagic stroke more significantly than SAPT and the cilostazol combination did not increase hemorrhagic stroke compared to SAPT. The outcomes from the 2 cilostazol regimens were comparable to SAPT in the case of myocardial infarction. Conclusions- Cilostazol is a more effective and safer treatment option than SAPT approaches using mainly aspirin. Cilostazol regimens can also be modified to clinical situations as this drug reduces recurrent and ischemic stroke more efficiently as a combination therapy but is more beneficial for hemorrhagic stroke as a monotherapy.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Cilostazol/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Prevenção Secundária/métodos , Acidente Vascular Cerebral/tratamento farmacológico , Aspirina/uso terapêutico , Clopidogrel/uso terapêutico , Quimioterapia Combinada , Humanos , Hemorragias Intracranianas/epidemiologia , Infarto do Miocárdio/epidemiologia , Recidiva
9.
Cerebrovasc Dis ; 43(3-4): 139-144, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28088803

RESUMO

BACKGROUND: Although size is one of the strongest predictors, small aneurysms often rupture. We compared the characteristics of small and large ruptured intracranial aneurysms (RIAs) according to their location to find the factors associated with small RIAs in each location. METHODS: Patients with subarachnoid hemorrhage due to saccular RIAs were consecutively enrolled. The sizes were dichotomized as small (<5 mm) or large, and the location was classified as paraclinoid-distal internal carotid artery, sidewalls of anterior or middle cerebral artery (MCA; sidewall), MCA-bifurcation, anterior or posterior communicating artery (Acom or Pcom, respectively), and posterior circulation RIAs. Independent factors associated with small RIAs compared to large RIAs were investigated in each location. RESULTS: Small RIAs were observed in 384 of 791 patients (48.5%), and were most commonly located at Acom (17.1%) followed by Pcom (9.0%) and sidewalls (7.2%). Female sex (OR 3.038; 95% CI 2.099-4.395), young age (OR 0.971; 95% CI 0.958-0.985), hypertension (OR 1.412; 95% CI 1.033-1.930) and multiple aneurysms (OR 1.942; 95% CI 1.335-2.824) were associated with small RIAs. By location, sidewall aneurysms (OR 2.183; 95% CI 1.049-4.542) were associated with small RIAs, whereas MCA-bifurcation (OR 0.318; 95% CI 0.168-0.599) and Pcom aneurysms (OR 0.511; 95% CI 0.277-0.944) were associated with large RIAs. The presence of multiple aneurysms (OR 4.69; 95% CI 1.45-21.19) was associated with small RIAs at sidewalls, and young age, female sex, hypertension and the presence of bilateral A1 (OR 1.85; 95% CI 1.09-3.13) were associated with small RIAs at Acom. Acom RIAs with bilateral A1 was smaller than those with unilateral A1 (4.7 ± 2.1 vs. 5.8 ± 2.6 mm; p < 0.001). CONCLUSIONS: Intracranial aneurysms which rupture below 5 mm are not uncommon, and the factors associated with small-sized RIAs differ according to location. Sidewall aneurysms, with multiple aneurysms and Acom aneurysms with bilateral A1 may rupture even at small size.


Assuntos
Aneurisma Roto/etiologia , Aneurisma Intracraniano/etiologia , Hemorragia Subaracnóidea/etiologia , Aneurisma Roto/diagnóstico por imagem , Angiografia Cerebral/métodos , Angiografia por Tomografia Computadorizada , Bases de Dados Factuais , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Modelos Logísticos , Masculino , Análise Multivariada , Razão de Chances , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Hemorragia Subaracnóidea/diagnóstico por imagem
10.
Mediators Inflamm ; 2017: 1958947, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29362519

RESUMO

Visfatin is an adipokine that is secreted from adipose tissue, and it is involved in a variety of physiological processes. In particular, visfatin has been implicated in metabolic diseases, such as obesity and type 2 diabetes, which are directly linked to systemic inflammation. However, the potential impacts of visfatin on the hypothalamic control of energy homeostasis, which is involved in microglial inflammation, have not fully been investigated. In this study, we found that treatment with exogenous recombinant visfatin protein led to the activation of the inflammatory response in a microglial cell line. In addition, we observed that central administration of visfatin led to the activation of microglia in the hypothalamus. Finally, we found that visfatin reduced food intake and body weight through activating POMC neurons in association with microglia activation in mice. These findings indicate that elevation of central visfatin levels may be associated with homeostatic feeding behavior in response to metabolic shifts, such as increased adiposity following inflammatory processes in the hypothalamus.


Assuntos
Anorexia/induzido quimicamente , Hipotálamo/imunologia , Inflamação/etiologia , Microglia/imunologia , Nicotinamida Fosforribosiltransferase/farmacologia , Redução de Peso/efeitos dos fármacos , Animais , Células Cultivadas , Comportamento Alimentar/efeitos dos fármacos , Masculino , Camundongos , Nicotinamida Fosforribosiltransferase/administração & dosagem
11.
J Perinat Med ; 45(1): 11-20, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27124668

RESUMO

BACKGROUND: The safety of preventive progestogen therapy for preterm birth remains to be established. This meta-analysis aimed to evaluate the effects of preventive progestogen therapy on neonatal mortality. METHODS: Randomized controlled trials (RCTs) on the preventive use of progestogen therapy, published between October 1971 and November 2015, were identified by searching MEDLINE/PubMed, EMBASE, Scopus, ClinicalTrials.gov, Cochrane Library databases, CINAHL, POPLINE, and LILACS using "progesterone" and "preterm birth" as key terms. We conducted separate analyses according to the type of progestogen administered and plurality of the pregnancy. RESULTS: Twenty-two RCTs provided data on 11,188 neonates. Preventive progestogen treatment in women with a history of preterm birth or short cervical length was not associated with increased risk of neonatal death compared to placebo in all analyzed progestogen types and pregnancy conditions. The pooled relative risks (95% confidence interval) of neonatal mortality were 0.69 (0.31-1.54) for vaginal progestogen in singleton pregnancies, 0.6 (0.33-1.09) for intramuscular progestogen in singleton pregnancies, 0.96 (0.51-1.8) for vaginal progestogen in multiple pregnancies, and 0.96 (0.49-1.9) for intramuscular progestogen in multiple pregnancies. CONCLUSIONS: The results of this meta-analysis suggest that administration of preventive progestogen treatment to women at risk for preterm birth does not appear to negatively affect neonatal mortality in single or multiple pregnancies regardless of the route of administration.


Assuntos
Nascimento Prematuro/prevenção & controle , Progestinas/uso terapêutico , Caproato de 17 alfa-Hidroxiprogesterona , Administração Intravaginal , Feminino , Humanos , Hidroxiprogesteronas/administração & dosagem , Lactente , Mortalidade Infantil , Recém-Nascido , Injeções Intramusculares , Gravidez , Gravidez Múltipla , Progesterona/administração & dosagem
12.
Cerebrovasc Dis ; 42(5-6): 387-394, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27359223

RESUMO

BACKGROUND: There has been no large-scale trial comparing endovascular treatment (add-on EVT) after intravenous tissue plasminogen activator (IV tPA) and IV tPA alone in acute ischemic stroke (AIS) caused by internal carotid artery occlusion (ICAO). We aimed at investigating the effectiveness and safety of add-on EVT after IV tPA in AIS patients with ICAO. METHODS: Between March 2010 and March 2013, 3,689 consecutive ischemic stroke patients who were hospitalized within 4.5 h of onset were identified using a prospective stroke registry at 11 centers in Korea. Among them, patients with persistent ICAO after receiving IV tPA and whose 3-month modified Rankin Scale (mRS) was available were finally enrolled. A propensity score analysis with inverse-probability of treatment weighting was used to eliminate baseline imbalances between those receiving add-on EVT and IV tPA alone. RESULTS: Among 264 patients enrolled in this study (mean age 71.4; male 56.4%; median National Institute of Health Stroke Scale score 15), 117 (44.3%) received add-on EVT. The add-on EVT group had a higher frequency of favorable outcome on the mRS ≤2 (35.0 vs. 18.4%; adjusted OR (aOR) 2.79; 95% CI 1.66-4.67) and lower mortality (17.9 vs. 35.4%; aOR 0.24; 95% CI 0.13-0.42) at 3 months, when compared to the IV tPA-alone group. Add-on EVT did not significantly increase the risk of symptomatic hemorrhage (5.1 vs. 4.1%; aOR 1.01; 95% CI 0.37-2.70). The rate of successful recanalization (thrombolysis in cerebral infarction grade ≥2b) in the add-on EVT group was 69.2%. CONCLUSIONS: Compared to an IV tPA alone, add-on EVT can improve clinical outcomes in patients with symptomatic ICAO within 4.5 h of onset without a significant increase of symptomatic hemorrhage.


Assuntos
Artéria Carótida Interna , Estenose das Carótidas/terapia , Procedimentos Endovasculares , Fibrinolíticos/administração & dosagem , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/fisiopatologia , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/fisiopatologia , Terapia Combinada , Avaliação da Deficiência , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Infusões Intravenosas , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pontuação de Propensão , Fluxo Sanguíneo Regional , Sistema de Registros , República da Coreia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tempo para o Tratamento , Resultado do Tratamento , Grau de Desobstrução Vascular , Adulto Jovem
13.
J Obstet Gynaecol ; 36(5): 563-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26965725

RESUMO

Varicella-zoster virus (VZV) is a teratogen that can cross the placenta and cause the congenital varicella syndrome (CVS), which is characterised by multi-system anomalies. There have been 130 reported cases of CVS from 1947 to 2013. The estimated incidence of CVS was 0.59% and 0.84% for women infected with VZV during the entire pregnancy and for those infected the first 20 weeks of pregnancy, respectively. Nine cases were reported at 21-27 weeks of gestation and one case was identified at 36 weeks. Herpes zoster caused CVS in two cases. Regarding treatment, varicella zoster immunoglobulin treatment, irrespective of gestational age, should be considered in addition to antiviral drugs for women who have been exposed to or infected with virus.


Assuntos
Varicela/congênito , Doenças Fetais/epidemiologia , Herpesvirus Humano 3 , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Complicações Infecciosas na Gravidez/epidemiologia , Adulto , Varicela/transmissão , Varicela/virologia , Feminino , Doenças Fetais/virologia , Idade Gestacional , Humanos , Incidência , Recém-Nascido , Masculino , Gravidez , Complicações Infecciosas na Gravidez/virologia , Síndrome
14.
Stroke ; 46(11): 3093-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26451026

RESUMO

BACKGROUND AND PURPOSE: With the increased investigation of cerebral arteries using magnetic resonance angiography in the general population, the detection of unruptured intracranial aneurysms (UIAs) has increased. Understanding the distribution and factors associated with UIAs might be helpful for understanding the pathomechanism. METHODS: Subjects who underwent magnetic resonance angiography with a health examination at the Health Screening and Promotion Center were enrolled. The incidence and risk factors of UIAs (age, sex, hypertension, diabetes mellitus, smoking, alcohol, and coronary artery disease) were investigated by comparing patients with and without UIAs. These risk factors were also investigated by the UIA location, distal internal carotid artery, anterior cerebral artery and middle cerebral artery (MCA), MCA bifurcation, anterior and posterior communicating artery, and posterior circulation. RESULTS: Among 187 166 subjects who received health examination, 18 954 underwent magnetic resonance angiography. Of them, 367 (1.93%) had UIAs. Age (odds ratio [OR], 1.02; P=0.003), women (OR, 2.00; P<0.001), hypertension (OR, 2.21; P<0.001), smoking (OR, 1.66; P=0.001), and coronary artery disease (OR, 0.23; P<0.001) were independently associated with the presence of UIAs. Hypertension was associated with most UIAs, except for those located at sidewalls (anterior cerebral artery and MCA). MCA aneurysms were associated with old age and smoking. Distal internal carotid artery, posterior communicating artery, and MCA-bifurcation aneurysms were associated with female sex. Anterior communicating artery aneurysms were associated with smoking and alcohol. Posterior circulation UIAs were only associated with hypertension. Coronary artery disease was negatively associated with anterior circulation aneurysms. CONCLUSIONS: The risk factors for UIAs differ by their location, compared with the control. Interestingly, the presence of coronary artery disease was protective against the presence of UIAs.


Assuntos
Aneurisma Intracraniano/diagnóstico , Aneurisma Intracraniano/epidemiologia , Angiografia por Ressonância Magnética , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Feminino , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Aneurisma Intracraniano/etiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia
15.
Artif Organs ; 39(2): 110-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24787892

RESUMO

The aim of this study was to determine whether pulsatile or nonpulsatile perfusion had a greater effect on pulmonary dysfunction in randomized controlled trials. MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were used to identify available articles published before April 13, 2013. A meta-analysis was conducted on the effects of pulsatile perfusion on postoperative pulmonary function, intubation time, and the lengths of intensive care unit (ICU) and hospital stays. Eight studies involving 474 patients who received pulsatile perfusion and 496 patients who received nonpulsatile perfusion during cardiopulmonary bypass (CPB) were considered in the meta-analysis. Patients receiving pulsatile perfusion had a significantly greater PaO2 /FiO2 ratio 24 h and 48 h post-operation (P < 0.00001, both) and significantly lower chest radiograph scores at 24 h and 48 h post-operation (P < 0.00001 and P = 0.001, respectively) compared with patients receiving nonpulsatile perfusion. The incidence of noninvasive ventilation for acute respiratory insufficiency was significantly lower (P < 0.00001), and intubation time and ICU and hospital stays were shorter (P = 0.004, P < 0.00001, and P < 0.00001, respectively) in patients receiving pulsatile perfusion during CPB compared with patients receiving nonpulsatile perfusion. In conclusion, our meta-analysis suggests that the use of pulsatile flow during CPB results in better postoperative pulmonary function and shorter ICU and hospital stays.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Ponte Cardiopulmonar/métodos , Pulmão/fisiologia , Perfusão/métodos , Fluxo Pulsátil , Humanos , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Radiografia , Resultado do Tratamento
16.
J Stroke Cerebrovasc Dis ; 24(8): 1873-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26004860

RESUMO

BACKGROUND: Although recent studies have shown that the elevation of serum triglyceride (TG) is related to the increased incidence of ischemic stroke, the relationship between hypertriglyceridemia and subtypes of ischemic stroke is largely unknown. This study attempted to evaluate whether hypertriglyceridemia is associated with lacunar stroke in diabetes mellitus (DM). METHODS: A total of 2141 consecutive patients with acute ischemic stroke were enrolled from March 2005 to April 2014, excluding the subjects with undetermined/other determined etiology or no lipid data. We compared the lipid profiles among stroke subtypes. The estimated serum TG levels and the interaction between DM and stroke subtypes were determined by analysis of covariance (ANCOVA) and Tukey's multiple comparison. RESULTS: In ANCOVA test, the difference of estimated TG between DM and non-DM patients was largest in small-vessel occlusion (SVO; 159.7 [95% confidence interval {CI}, 143.2-176.2] versus 122.4 [95% CI, 106.1-138.7]), and a significant interaction was observed between DM and stroke subtypes for TG levels (P = .013) but not for total cholesterol (P = .363), low-density lipoprotein cholesterol (P = .171), or high-density lipoprotein cholesterol (P = .231). By Tukey's multiple comparison, SVO was consistently associated with DM for serum TG levels (P < .001). CONCLUSIONS: In acute ischemic stroke with DM, serum TG level was significantly associated with lacunar infarction adjusting for other lipid profiles and vascular risk factors. Further studies are warranted to reveal the pathophysiologic implication of hypertriglyceridemia for lacunar infarction in type 2 DM.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Hipertrigliceridemia/etiologia , Acidente Vascular Cerebral Lacunar/etiologia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Colesterol/sangue , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/complicações
17.
J Stroke Cerebrovasc Dis ; 23(5): e331-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24560247

RESUMO

BACKGROUND: Intracranial arterial calcification (IAC) is an evidence of advanced atherosclerosis. This study was aimed to investigate whether IAC predicts early vascular events (EVEs) during acute period of ischemic stroke. METHODS: We prospectively enrolled consecutive patients with acute ischemic stroke and transient ischemic attack within 48 hours from January 2005 to October 2012. Three IAC categories were defined according to the total IAC score as follows: no IAC (0 point), mild IAC (1-2 points), and severe IAC (≥3 points). EVEs included early progression/recurrence of stroke, coronary events, and vascular deaths within 2 weeks from stroke onset. We used multivariable Cox regression analyses to determine the effect of IAC on EVE. RESULTS: In the trend analysis of 1017 total patients, there were significant trends of increased IAC toward higher total EVEs (10.5% versus 13.8% versus 21.2%, P < .001). Severe IAC was related to increased rate of early progression/recurrence (hazard ratio [HR] 2.00; 95% confidence interval [CI] 1.07-3.71, P = .029) and coronary events (HR 3.51; 95% CI 1.00-12.31, P = .050) but did not show an association for mortality (HR .54; 95% CI .19-1.53, P = .224). Increased IAC was also related to a poor functional outcome after 3 months (odds ratio 2.23; 95% CI 1.38-3.59). CONCLUSIONS: IAC was significantly associated with increased early progression/recurrence of stroke and coronary events during acute period of ischemic stroke. IAC on the initial brain computed tomography would be used as a predictor for recurrent vascular events after acute ischemic stroke before further angiographic evaluation.


Assuntos
Isquemia Encefálica/etiologia , Doenças Arteriais Cerebrais/complicações , Ataque Isquêmico Transitório/etiologia , Acidente Vascular Cerebral/etiologia , Calcificação Vascular/complicações , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/mortalidade , Doenças Arteriais Cerebrais/diagnóstico , Doenças Arteriais Cerebrais/mortalidade , Distribuição de Qui-Quadrado , Progressão da Doença , Feminino , Humanos , Ataque Isquêmico Transitório/diagnóstico , Ataque Isquêmico Transitório/mortalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Sistema de Registros , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/mortalidade , Calcificação Vascular/diagnóstico , Calcificação Vascular/mortalidade
18.
Chem Commun (Camb) ; 60(5): 590-593, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38099698

RESUMO

Anisotropic lens-shaped nitrogen-doped carbon (Lens-NMC) with unidirectionally aligned mesopores was achieved via perpendicular block copolymer self-assembly at the polymer interface. Lens-NMC is applied as a potassium-ion battery anode material as a next-generation battery system.

19.
ACS Nano ; 18(20): 12853-12860, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38718347

RESUMO

Magnetic random-access memory (MRAM), which stores information through control of the magnetization direction, offers promising features as a viable nonvolatile memory alternative, including high endurance and successful large-scale commercialization. Recently, MRAM applications have extended beyond traditional memories, finding utility in emerging computing architectures such as in-memory computing and probabilistic bits. In this work, we report highly reliable MRAM-based security devices, known as physical unclonable functions (PUFs), achieved by exploiting nanoscale perpendicular magnetic tunnel junctions (MTJs). By intentionally randomizing the magnetization direction of the antiferromagnetically coupled reference layer of the MTJs, we successfully create an MRAM-PUF. The proposed PUF shows ideal uniformity and uniqueness and, in particular, maintains performance over a wide temperature range from -40 to +150 °C. Moreover, rigorous testing with more than 1584 challenge-response pairs of 64 bits each confirms resilience against machine learning attacks. These results, combined with the merits of commercialized MRAM technology, would facilitate the implementation of MRAM-PUFs.

20.
ACS Appl Mater Interfaces ; 16(21): 27566-27575, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38743438

RESUMO

We selectively improved the viewing angle characteristics and light extraction efficiency of blue thermally activated delayed fluorescence (TADF) organic light-emitting diodes (OLEDs) by tailoring a nanofiber-shaped Si3N4 layer, which was used as an internal scattering layer. The diameter of the polymer nanofibers changed according to the mass ratio of polyacrylonitrile (PAN) and poly(methyl methacrylate) (PMMA) in the polymer solution for electrospinning. The Si3N4 nanofiber (SNF) structure was fabricated by etching an Si3N4 film using the PAN/PMMA nanofiber as a mask, making it easier to adjust parameters, such as the diameter, open ratio, and height, even though the SNF structure was randomly shaped. The SNF structures exhibited lower transmittance and higher haze with increasing diameter, showing little correlation with their height. However, all the structures demonstrated a total transmittance of over 80%. Finally, by applying the SNF structures to the blue TADF OLEDs, the external quantum efficiency was increased by 15.6%. In addition, the current and power efficiencies were enhanced by 23.0% and 25.6%, respectively. The internal light-extracting SNF structure also exhibited a synergistic effect with the external light-extracting structure. Furthermore, when the viewing angle changed from 0° to 60°, the peak wavelength and CIE coordinate shift decreased from 20 to 6 nm and from 0.0561 to 0.0243, respectively. These trends were explained by the application of Snell's law to the light path and were ultimately validated through finite-difference time-domain simulations.

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