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1.
Epidemiol Health ; : e2022009, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34990528

RESUMO

Objectives: The purpose of the current study is to examine 1) whether the addition of resting heart rate (RHR) to existing undiagnosed diabetes (UnDM) prediction model would improve predictability, 2) to develop and validate UnDM prediction model by only using easily assessable variables such as age, gender, RHR and waist circumference (WC). Methods: Korea National Health and Nutrition Examination Survey (KNHANES) 2010, 2012, 2014, 2016 data were used to develop the model (model building set, N=19,675) and KNHANES data from 2011, 2013, 2015, 2017 were used to validate the model (validation set, N=19,917). UnDM was defined as a fasting glucose level ≥ 126mg/dL or hemoglobin A1c ≥6.5%, yet has not been diagnosed by doctors. SPSS logistic regression analysis was used to determine predictors of UnDM. Results: Age, RHR, waist circumference (WC) were associated with UnDM. When RHR was added to the existing model, sensitivity was reduced (86% vs. 73%) while specificity was increased (49% vs. 65%), expressed as higher Youden index (35 vs. 38). When only age, sex, WC and RHR were used in the model, sensitivity of 70%, and specificity of 67% with Youden index of 37 were observed. Conclusion: Adding RHR to existing UnDM prediction model improved specificity and Youden index. Furthermore, prediction model only used age, sex, RHR and WC were not inferior to existing prediction model.

2.
Adv Mater ; 33(44): e2102542, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34514649

RESUMO

Since the 4th Industrial Revolution, Internet of Things based environments have been widely used in various fields ranging from mobile to medical devices. Simultaneously, information leakage and hacking risks have also increased significantly, and secure authentication and security systems are constantly required. Physical unclonable functions (PUF) are in the spotlight as an alternative. Chaotic phosphorescent patterns are developed based on an organic crystal and atomic seed heterostructure for security labels with PUFs. Phosphorescent organic crystal patterns are formed on MoS2 . They seem similar on a macroscopic scale, whereas each organic crystal exhibits highly disorder features on the microscopic scale. In image analysis, an encoding capacity as a single PUF domain achieves more than 1017 on a MoS2 small fragment with lengths of 25 µm. Therefore, security labels with phosphorescent PUFs can offer superior randomness and no-cloning codes, possibly becoming a promising security strategy for authentication processes.

3.
Medicine (Baltimore) ; 100(29): e26682, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34398037

RESUMO

RATIONALE: Nocardiosis is an uncommon and potentially life-threatening infection that usually affects immunocompromised hosts. No clinical guidelines have been established for managing this rare disease, and the optimal treatment modality remains unclear. Nocardia farcinica, a relatively infrequent pathogen of nocardiosis, causes a clinically aggressive infection. In addition to our patient data, our search of the literature for patients who presented with empyema caused by N. farcinica will provide fundamental information for optimal treatment modalities. PATIENT CONCERNS: A 64-year-old man was diagnosed with empyema, 4 days following surgery for sigmoid colon cancer. Brain lesions were evaluated only after N. farcinica was isolated and identified as the causative pathogen through repeated culture tests. DIAGNOSES: N. farcinica was isolated from the pleural effusion and confirmed as the pathogen through 16S rRNA sequencing. INTERVENTIONS: The patient was successfully treated with tube thoracotomy, neurosurgical evacuation, and a combination of trimethoprim/sulfamethoxazole plus imipenem. Long-term antibiotic therapy was required to prevent recurrence. OUTCOMES: Pyothorax showed a good clinical response to antimicrobial therapy and drainage of pleural effusion, whereas brain abscess did not respond to medical therapy and required surgery. The patient eventually recovered and continued chemotherapy as treatment for sigmoid colon cancer. LESSONS: Although extremely rare, this report demonstrates the importance of considering Nocardia infection as the differential diagnosis in immunocompromised patients who present with empyema. In particular, because of the N. farcinica infection's tendency to spread and the resistance of the organism to antibiotics, aggressive evaluation of metastatic lesions and standardized support from microbiological laboratories are important. Surgery may be required in some patients with brain abscesses to improve the chance of survival.


Assuntos
Adenocarcinoma , Abscesso Encefálico/diagnóstico , Neoplasias do Colo , Empiema/diagnóstico , Nocardiose/diagnóstico , Nocardia/isolamento & purificação , Anti-Infecciosos/uso terapêutico , Abscesso Encefálico/complicações , Abscesso Encefálico/diagnóstico por imagem , Abscesso Encefálico/tratamento farmacológico , Diagnóstico Diferencial , Empiema/complicações , Empiema/diagnóstico por imagem , Empiema/tratamento farmacológico , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Nocardiose/complicações , Nocardiose/diagnóstico por imagem , Nocardiose/tratamento farmacológico , Tomografia Computadorizada por Raios X , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
4.
Cell Transplant ; 30: 9636897211023474, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34176333

RESUMO

Human adipose-derived mesenchymal stem cells (hAMSCs) are capable of immunomodulation and regeneration after neural injury. For these reasons, hAMSCs have been investigated as a promising stem cell candidate for stroke treatment. However, noninvasive experiments studying the effects of grafted stem cells in the host brain have not yet been reported. Cerebrospinal fluid (CSF), which can be collected without sacrificing the subject, is involved in physiological control of the brain and reflects the pathophysiology of various neurological disorders of the central nervous system (CNS). Following stem cell transplantation in a stroke model, quantitative analysis of CSF proteome changes can potentially reveal the therapeutic effect of stem cells on the host CNS. We examined hAMSC-secreted proteins obtained from serum-free culture medium by liquid chromatography-tandem mass spectrometry (LC-MS/MS), which identified several extracellular matrix proteins, supporting the well-known active paracrine function of hAMSCs. Subsequently, we performed label-free quantitative proteomic analysis on CSF samples from rat stroke models intravenously injected with hAMSC (experimental) or phosphate buffered saline (control). In total, 524 proteins were identified; among them, 125 and 91 proteins were increased and decreased with hAMSC treatment, respectively. Furthermore, gene set enrichment analysis revealed three proteins, 14-3-3 theta, MAG, and neurocan, that showed significant increases in the hAMSC-treated model; these proteins are core members of neurotrophin signaling, nerve growth factor (NGF) signaling, and glycosaminoglycan metabolism, respectively. Subsequent histological and neurologic function experiments validated proliferative neurogenesis in the hAMSC-treated stroke model. We conclude that (i) intravenous injection of hAMSCs can induce neurologic recovery in a rat stroke model and (ii) CSF may reflect the therapeutic effect of hAMSCs. Additionally, proteins as 14-3-3 theta, MAG, and neurocan could be considered as potential CSF biomarkers of neuroregeneration. These CSF proteome profiling results would be utilized as valuable resource in further stroke studies.

5.
Sci Rep ; 11(1): 13066, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34158561

RESUMO

This study aimed to investigate the association between domain-specific physical activity (PA) and diabetes in Korean adults. We analyzed 26,653 men and women (aged > 18 years) from the Korea National Health and Nutrition Examination Survey (2014-2018). PA was measured using a validated Global PA Questionnaire. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) after adjustment for various confounders. Transport PA accounted for the majority of total PA (46%, men; 58%, women), followed by leisure-time PA (30%; 22%) and work PA (24%; 20%). In men, ORs (95% CI) of diabetes comparing ≥ 600 metabolic task of equivalent (MET)-min/week vs. no activity were 0.82 (0.71-0.95) for leisure-time PA, 0.85 (0.75-0.96) for transport PA, and 0.88 (0.78-0.99) for leisure-time + transport PA. In women, ORs (95% CI) of diabetes comparing the same groups were 0.73 (0.60-0.89) for leisure-time PA, 0.97 (0.85-1.10) for transport PA, and 0.88 (0.78-1.00) for leisure-time + transport PA. However, work PA showed no association with diabetes. In conclusion, leisure-time PA was inversely associated with diabetes in both men and women, while transport PA was inversely associated only in men. But work PA was not associated with diabetes in Korean adults.


Assuntos
Diabetes Mellitus/epidemiologia , Exercício Físico/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , República da Coreia/epidemiologia
6.
Sensors (Basel) ; 20(23)2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33271990

RESUMO

The purpose of our study was to validate a newly developed breath acetone (BrAce) analyzer, and to explore if BrAce could predict aerobic exercise-related substrate use. Six healthy men ran on a treadmill at 70% of maximal oxygen consumption (VO2max) for 1 h after two days of a low-carbohydrate diet. BrAce and blood ketone (acetoacetate (ACAC), beta-hydroxybutyrate (BOHB)) levels were measured at baseline and at different time points of post-exercise. BrAce values were validated against blood ketones and respiratory exchange ratio (RER). Our results showed that BrAce was moderately correlated with BOHB (r = 0.68, p < 0.01), ACAC (r = 0.37, p < 0.01) and blood ketone (r = 0.60, p < 0.01), suggesting that BrAce reflect blood ketone levels, which increase when fat is oxidized. Furthermore, BrAce also negatively correlated with RER (r = 0.67, p < 0.01). In our multiple regression analyses, we found that when BMI and VO2max were added to the prediction model in addition to BrAce, R2 values increased up to 0.972 at rest and 0.917 at 1 h after exercise. In conclusion, BrAce level measurements of our BrAce analyzer reflect blood ketone levels and the device could potentially predict fat oxidation.


Assuntos
Acetona , Testes Respiratórios , Gastos em Saúde , Ácido 3-Hidroxibutírico , Metabolismo Energético , Exercício Físico , Humanos , Masculino , Oxirredução , Consumo de Oxigênio
7.
Artigo em Inglês | MEDLINE | ID: mdl-33052030

RESUMO

AIM: Behavioral interventions such as exercise may induce epigenetic changes. Only few studies investigated the effects of exercise on epigenetic alterations in colorectal cancer survivors. The aim of this study was to explore the changes of genome-wide DNA methylation after 6-week exercise training in colorectal cancer survivors. METHODS: This preliminary study used a subset of data from a randomized controlled trial in 15 colorectal cancer survivors. Participants were randomized either to the 6-week exercise group or control group. The exercise intervention consisted of a weekly, group-based, supervised resistance exercise program and a home-based same resistance exercise plus walking six times per week. Blood samples were collected at baseline and after the intervention and data from eight subjects were analyzed for genome-wide DNA methylation on 865,918 CpG sites. RESULTS: Compared to the control group, the exercise group shows notable methylation changes in 756 CpG sites (22.7-25.2%). Gene ontology and disease annotation analysis showed that the genes targeting 81 CpG sites in promoter region with significant group-difference were linked in biological process such as immune response and transcription and related to metabolic and immune diseases. Also, hypermethylation on genes related to disease prevention seemed to be inhibited in the exercise group compared to the control group, indicating a likelihood of transcriptional activity of these genes. CONCLUSION: We found a preliminary evidence of the positive effects of exercise intervention on epigenetic markers in colorectal cancer survivors. Larger scale randomized controlled trials are warranted to further investigate our findings.

8.
Adv Mater ; 32(51): e2002213, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33035387

RESUMO

Organic semiconductors are photonic and electronic materials with high luminescence, quantum efficiency, color tunability, and size-dependent optoelectronic properties. The self-assembly of organic molecules enables the establishment of a fabrication technique for organic micro- and nano-architectures with well-defined shapes, tunable sizes, and defect-free structures. DNAs, a class of biomacromolecules, have recently been used as an engineering material capable of intricate nanoscale structuring while simultaneously storing biological genetic information. Here, the up-to-date research on hybrid materials made from organic semiconductors and DNAs is presented. The trends in photonic and electronic phenomena discovered in DNA-functionalized and DNA-driven organic semiconductor hybrids, comprising small molecules and polymers, are observed. Various hybrid forms of solutions, arrayed chips, nanowires, and crystalline particles are discussed, focusing on the role of DNA in the hybrids. Furthermore, the recent technical advances achieved in the integration of DNAs in light-emitting devices, transistors, waveguides, sensors, and biological assays are presented. DNAs not only serve as a recognizing element in organic-semiconductor-based sensors, but also as an active charge-control material in high-performance optoelectronic devices.


Assuntos
DNA/química , Compostos Orgânicos/química , Semicondutores
9.
Tissue Eng Regen Med ; 17(5): 695-704, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32901436

RESUMO

BACKGROUND: Mannitol increases blood-brain barrier permeability and can improve the efficiency of systemically administered stem cells by facilitating stem cell entry from the periphery into the injured brain. The aim of this study was to elucidate the neuroprotective effects of a combination of mannitol pretreatment and stem cell transplantation on stroke-induced neural injury. METHODS: The experimental rats were randomly assigned to three groups 24 h after middle cerebral artery occlusion and reperfusion. One group received intravenous (IV) injections of phosphate-buffered saline (vehicle), another group received IV injections of human adipose-derived stem cells (hADSCs), and the last group received IV injections of hADSCs 10 min after IV mannitol injections. Neurobehavioral functions and infarct volume were compared. Immunohistochemistry (IHC) analyses were performed using antibodies against ionized calcium binding adapter-1 (IBA-1), rat endothelial antigen-1 (RECA-1), and bromodeoxyuridine/doublecortin (BrdU/DCX). RESULTS: PKH-26 labeling revealed no difference in the number of stem cells that had migrated into the injured brain, and hADSC transplantation did not improve the infarct volume. However, neurobehavioral functions improved in the mannitol group. IHC showed higher numbers of RECA-1-positive cells in the peri-infarcted brain and BrdU-/DCX-colocalized cells in the subventricular zone in the mannitol group. IBA-1-positive cell number decreased in the hADSC-only and mannitol-pretreatment groups compared with the vehicle group even though there was no difference between the former two groups. CONCLUSION: Combinatorial treatment with mannitol and hADSC transplantation may have better therapeutic potential than hADSC monotherapy for ischemic stroke.


Assuntos
Manitol , Acidente Vascular Cerebral , Animais , Movimento Celular , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/tratamento farmacológico , Ratos , Transplante de Células-Tronco , Acidente Vascular Cerebral/tratamento farmacológico
10.
Adv Mater ; 32(45): e2005238, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32969091

RESUMO

A successful identification of DNA-DNA recognition, based on the waveguide effect of a 1D hybrid prismatic hexagon crystal interfacing of DNA with an organic semiconductor is achieved. This bio-hybrid 1D crystal simultaneously discerns the complementary case at its one end against a 1-mer mismatch in 27-mer nucleic acid sequence at the other end. The loss coefficient value of this waveguide is estimated to be 0.159 µm-1 for the perfect match, which is a stark discrepancy compared to 0.244 µm-1 for the 1-mer mismatch, implying waveguide performance with a higher efficiency. These results demonstrate successfully that multiple biological interactions can be realized by the optical waveguide of the single 1D bio-hybrid-crystal and will push this class of materials into bio-related applications.


Assuntos
DNA/química , Óptica e Fotônica , Semicondutores , Pareamento Incorreto de Bases , DNA/genética
11.
Macromol Rapid Commun ; 41(21): e2000164, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32578310

RESUMO

π-Conjugated polymers have become qualified candidates for biosensing owing to their unique optoelectronic properties and excellent biocompatibility. In this contribution, nucleotide mismatches in DNA hybridization, being variable in position, are reflected in a stark manner by poly(3-methylthiophene) (P3MT) nanowires (NWs), in which probe DNA sequence is properly functionalized. Selected as the systematic investigation are complementary target DNA (tDNA), random sequence DNA, and three kinds of 1-mer mismatched tDNAs with different mismatch loci away from the NW's surface. Nanoscale optical observation of the single P3MT NWs in solid states reveals that the more distant the mismatch position is from the surface, the higher the photoluminescence (PL) occurs, while the complementary sequence yields the highest but the random one remains the lowest. Hence, the PL intensity increases with the relative length of the DNA-DNA hybridization from the surface. These results deliver a new basis that π-conjugated polymers can be potentially applicable to detailed nucleotide analyses as in single nucleotide polymorphism.


Assuntos
Nanofios , DNA/genética , Hibridização de Ácido Nucleico , Nucleotídeos , Polímeros , Tiofenos
12.
Am J Cardiol ; 125(10): 1536-1542, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32241552

RESUMO

Mitral stenosis is classically caused by rheumatic disease (RMS). However, degenerative mitral stenosis (DMS) is increasingly encountered, particularly in developed countries with aging populations. The aim of this study was to compare clinical and echocardiographic characteristics between the 2 entities. One hundred fifteen patients with DMS were identified from an echocardiographic database in the United States and compared with 510 patients with RMS from Seoul, Korea. All subjects had a mitral valve area (MVA) ≤2.5 cm2 by continuity equation but were otherwise unselected. Patients with DMS were older and had more hypertension, diabetes, chronic kidney disease, and chronic obstructive pulmonary disease than those with RMS. Atrial fibrillation was more common in RMS patients. Mean mitral valve gradient was slightly lower in DMS versus RMS (7.63 ± 3.67 vs 8.50 ± 4.23 mm Hg, p = 0.04) but MVA was strikingly higher in the DMS group (1.35 ± 0.41 vs 0.95 ± 0.38 cm2, p <0.0001). This appeared to be due to greater stroke volume in the DMS patients (70.4 ± 19.7 vs 55.7 ± 15.5 ml, p <0.0001). Indexed left atrial volume was greater in RMS (82.1 ± 40.3 vs 57.9 ± 21.4 ml, p <0.0001) while estimated pulmonary artery systolic pressure was greater in DMS (49.3 ± 16.5 vs 39.4 ± 13.6 mm Hg, p <0.0001). In conclusion, DMS patients are older and have more comorbidities than RMS patients. DMS presents with greater MVA relative to mean mitral valve gradient than RMS. This appears due to a higher stroke volume in DMS patients.


Assuntos
Estenose da Valva Mitral/fisiopatologia , Cardiopatia Reumática/fisiopatologia , Fatores Etários , Idoso , Comorbidade , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/classificação , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/epidemiologia , República da Coreia/epidemiologia , Cardiopatia Reumática/diagnóstico por imagem , Cardiopatia Reumática/epidemiologia , Fatores de Risco , Estados Unidos/epidemiologia
13.
Polymers (Basel) ; 12(3)2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32164297

RESUMO

We experimentally demonstrate the simultaneous enhancement of Raman and photoluminescence (PL) of core-shell hybrid nanoparticles consisting of Ag (core) and polydiacetylene (PDA, shell) through the assistance of localized surface plasmon (LSP) effect for the effective biosensor. Core-shell nanoparticles (NPs) are fabricated in deionized water through a sequential process of reprecipitation and self-assembly. The Raman signal of PDA on core-shell NPs is enhanced more than 100 times. Also, highly enhanced photoluminescence is observed on Ag/PDA hybrid NPs after coupling of the complementary t-DNA with p-DNA which are immobilized on PDA shell. This indicates that the core Ag affects the Raman and PL of PDA through the LSP resonance, which can be caused by the energy and/or charge transfer caused by the LSP coupling and the strong electromagnetic field near Ag NP surface. Only electrons present on the surface interact with the PDA shell, not involving the electrically neutral part of the electrons inside the Ag NP. Furthermore, this work shows that as prepared Ag/PDA NPs functionalized by probe DNA can sense the target DNA with an attomolar concentration (100 attomole).

14.
J Korean Neurosurg Soc ; 63(2): 163-170, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32120456

RESUMO

OBJECTIVE: Milk fat globule-epidermal growth factor VIII (MFG-E8) may play a key role in inflammatory responses and has the potential to function as a neuroprotective agent for ameliorating brain injury in cerebral infarction. This study aimed to determine the role of MFG-E8 in brain injury in the subacute phase of cerebral ischemia in a rat model. METHODS: Focal cerebral ischemia was induced in rats by occluding the middle cerebral artery with the modified intraluminal filament technique. Twenty-four hours after ischemia induction, rats were randomly assigned to two groups and treated with either recombinant human MFG-E8 or saline. Functional outcomes were assessed using the modified Neurological Severity Score (mNSS), and infarct volumes were evaluated using histology. Anti-inflammation, angiogenesis, and neurogenesis were assessed using immunohistochemistry with antibodies against ionized calcium-binding adapter molecule 1 (Iba-1), rat endothelial cell antigen-1 (RECA-1), and bromodeoxyuridine (BrdU)/doublecortin (DCX), respectively. RESULTS: Our results showed that intravenous MFG-E8 treatment did not reduce the infarct volume; however, the mNSS test revealed that neurobehavioral deficits were significantly improved in the MFG-E8-treated group than in the vehicle group. Immunofluorescence staining revealed a significantly lower number of Iba-1-positive cells and higher number of RECA-1 in the periinfarcted brain region, and significantly higher numbers of BrdU- and DCX-positive cells in the subventricular zone in the MFG-E8-treated group than in the vehicle group. CONCLUSION: Our findings suggest that MFG-E8 improves neurological function by suppressing inflammation and enhancing angiogenesis and neuronal proliferation in the subacute phase of cerebral infarction.

15.
Eur Radiol ; 30(3): 1554-1563, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31705252

RESUMO

OBJECTIVES: To investigate the efficacy and safety of a new portable ultrasound-guided high-intensity focused ultrasound system (USgHIFU) with advanced targeting and beam steering technology for the treatment of uterine fibroids. METHODS: Fifty-nine uterine fibroids from 36 participants (mean age, 44.9 ± 4.1 years) were included from November 2013 to November 2015. All participants were treated with HIFU, with 3D electronic steering. MR imaging studies were performed before HIFU, immediately after HIFU, and 1 month and 3 (or 5) months after the HIFU treatment. The non-perfused volume ratio (NPVR), fibroid volume shrinkage (FVS), symptom improvement, quantified life quality assessment, and safety were analyzed. A long-term follow-up was conducted in July to December 2017 (mean, 32.2 months). RESULTS: The volume of the treated uterine fibroids ranged from 7.5 to 274.4 cm3 (mean, 69.8 cm3; SD, 64.3 cm3). The mean NPVR on the immediate post-HIFU MR imaging was 74.8 ± 25.2%. The mean FVS was 17.3% at 1 month, 33.3% at 3 months, and 45.1% at 5 months after HIFU treatment. The mean treatment time was 44.6 ± 28.2 min per fibroid and 72.9 ± 31.4 min per participant. Uterine fibroid-related symptoms and quality of life showed statistically significant improvement after the HIFU treatment. No significant symptoms related to safety or complications occurred. In the long-term follow-up, 78.8% of those surveyed were satisfied with their HIFU treatment. CONCLUSION: This clinical trial showed that a portable USgHIFU with advanced functions may safely and effectively treat uterine fibroids. KEY POINTS: • A portable compact ultrasound-guided high-intensity focused ultrasound (HIFU) can effectively and safely treat uterine fibroids. • Advanced functions, such as portability, targeted forecasting, electronic beam steering, and interleaved scanning, might be helpful in enhancing the clinical applicability of ultrasound-guided high-intensity focused ultrasound. • In the long-term follow-up of more than 2 years, approximately 80% of those surveyed were satisfied with their HIFU treatment.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Leiomioma/terapia , Qualidade de Vida , Terapia Assistida por Computador/métodos , Ultrassonografia de Intervenção/métodos , Neoplasias Uterinas/terapia , Adulto , Feminino , Humanos , Leiomioma/diagnóstico , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Satisfação Pessoal , Estudos Prospectivos , Resultado do Tratamento , Neoplasias Uterinas/diagnóstico
16.
Acta Biomater ; 101: 285-292, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610340

RESUMO

Recently, endovascular coil embolization has been introduced to treat intracranial aneurysms because it has lower morbidity and mortality than surgical clipping. The endovascular coils prevent the extravasation of blood by decreasing the permeability of an aneurysm flow governed by Darcy's law. Here, we developed and explored Pt-coated micro-ropes for potential use as endovascular coils. Electrospinning with subsequent electroplating were employed to fabricate Pt-coated nanofibers, which were tightly twisted to form micro-ropes. The compatibility of Pt micro-ropes with commercial delivery catheters was verified and their performance was experimentally explored in an in vitro experimental model. The developed Pt-coated micro-ropes demonstrated feasibility as efficient and low-cost endovascular coils. STATEMENT OF SIGNIFICANCE: The use of Platinum (Pt)-coated polymer nanofibers to prevent blood extravasation has been demonstrated. These Pt nanofibers were installed within a microfluidic channel, and the resulting reduced permeability was evaluated using a fluid similar to blood. Based on the obtained results, these newly developed nanofibers are expected to decrease the operation cost for aneurysmal subarachnoid hemorrhage (SAH), owing their reduced size and low material cost. Overall, the use of this new material should reduce the operational risk associated with the multiple steps required to place the Pt coils at the SAH site. The compatibility of Pt micro-ropes with commercial delivery catheters was verified and their performance was experimentally explored in an in vitro experimental model. The developed Pt-coated micro-ropes demonstrated feasibility as efficient and low-cost endovascular coils.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Embolização Terapêutica , Procedimentos Endovasculares , Nanofibras/química , Platina/farmacologia , Resinas Acrílicas/química , Cateteres , Galvanoplastia , Humanos , Nanofibras/ultraestrutura , Permeabilidade , Reologia , Bexiga Urinária/efeitos dos fármacos
17.
Materials (Basel) ; 12(7)2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30935003

RESUMO

We propose a design of angle-insensitive and polarization-independent reflective color filters with high efficiency (>80%) based on broad resonance in a Fabry⁻Pérot cavity where asymmetric metal-dielectric-metal planar structures are employed. Broadband absorption properties allow the resonance in the visible range to remain nearly constant over a broad range of incident angles of up to 40° for both s- and p-polarizations. Effects of the angles of incidence and polarization state of incident light on the purity of the resulting colors are examined on the CIE 1931 chromaticity diagram. In addition, higher-order resonances of the proposed color filters and their electric field distributions are investigated for improved color purity. Lastly, the spectral properties of the proposed structures with different metallic layers are studied. The simple strategy described in this work could be adopted in a variety of research areas, such as color decoration devices, microscopy, and colorimetric sensors.

18.
Polymers (Basel) ; 11(1)2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30960087

RESUMO

Self-healing, an autonomous repairing process stimulated by damage, has recently attracted a great deal of attention in the field of medical and mechanical engineering as well as from scientists, due to its valuable potential applications. However, as the self-healing process is mediated by specific functional materials, practical applications have been limited. Here, we introduce a healable homopolymer microcapsule that can self-heal a crack or cleaved part through a photochemical [2 + 2] cycloaddition process. Microcapsules were prepared through photopolymerization and suspension polymerization, each containing 1,1,1-tris (cinnamoyloxymethyl) ethane (TCE) and 1,1-di (cinnamoyloxymethyl) ethane (DCE) monomers, which act as healing materials. TCE and DCE monomers were polymerized into poly (TCE-co-DCE) without a photoinitiator under illumination. The epoxy specimen embedded with microcapsules showed obvious healing performance during illumination after cracking. From the FT-IR spectra for each step of the healing process, the specimen could be repeatedly self-healed through the reversible process of cyclobutane cross-links to the original cinnamate and vice versa. This work shows an alternative approach using homopolymer microcapsules to accomplish the repeatable self-healing of a crack without interface discontinuity, which could be adopted as a healing substance in various paints.

19.
Polymers (Basel) ; 11(4)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30978962

RESUMO

Chemical materials are sometimes harmful to the environment as well as humans, plants, and animals. Thus, high-performance sensor systems have become more important in the past few decades. To achieve pH scale sensing in nanosystems, we applied luminescence polymer nanowires with alumina oxide template method with electrochemical polymerization. We made polymer nanowire barcode by alternately stacking poly(3-methylthiophene) (P3MT) and poly(3,4-ethylenedioxythiophene) (PEDOT) in a nanoporous template. After polymerization, a hydrofluoric acid solvent was used to remove the template, and, for changing the pH scale, we used sodium hydroxide. We measured optical properties of each part of barcode using Raman scattering and photoluminescence and confirmed that only P3MT was changed by alkali treatment.

20.
Chempluschem ; 84(8): 1130-1134, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31943963

RESUMO

A single-benzene-based, blue-emissive diethyl 2,5-dihydroxyterephthalate (DDT) was prepared by Fischer esterification of 2,5-dihydroxyterephthalic acid (DHT) and ethanol. The strong fluorescence in both the solution and the solid state from such a simple framework stemmed from the push-pull structure of the electron-donating hydroxy groups and the accepting carbonyl groups, as well as structural planarity from intramolecular hydrogen bonds. The strong intermolecular hydrogen bonds enabled DDT to crystallize easily. The color CCD imaging technique showed efficient 1D optical waveguiding with a large optical loss coefficient of 0.15 dB/µm. DDT has potential application in optical sensors, photonic devices, and optoelectronic communication, because of its highly ordered structure and light-emitting ability.

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