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1.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38687155

RESUMO

This paper presents a novel six-axis force/torque (F/T) sensor design for robotics, combining ease of manufacturing with compactness. It features a high measuring range of ∼3700 N, an exceptional resolution of 0.1 N, and a rapid 5 kHz sampling rate. The sensor's design, focusing on durability and a wider sensing range, utilizes noncontact sensors and a streamlined structure. A novel force sensing scheme aligns sensing elements in-plane on a single printed circuit board, reducing the part count to four and the weight to under 80 g, while integrating an analog-to-digital converter to eliminate the need for external communication devices. The lightweight, efficient prototype demonstrates a superior performance and a high response frequency, validated against a reference F/T sensor.

2.
Medicina (Kaunas) ; 59(12)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38138229

RESUMO

Background and Objectives: Hip fractures are commonly found in elderly patients, and often result in chronic pain and decreased physical function, as well as worsening of overall health. It is known that early surgical intervention during the acute phase and rehabilitation are important for improving clinical outcomes for these patients. However, the importance of management for improving the quality of life of these patients is becoming more emphasized. Studies on changes in sleep patterns after hip fractures are rare overseas. Therefore, the aim of this study is to investigate the prevalence of sleep disturbance in patients with hip fractures and to analyze the changes in sleep disturbance after surgery by comparing the preoperative and postoperative results. Materials and Methods: During the period from August 2022 to January 2023, patients who underwent surgical treatment for hip fractures and were recruited into the REAL Hip Cohort were selected as research subjects. The sleep survey was conducted using the Pittsburgh Sleep Quality Index (PSQI). The PSQI is composed of 18 questions, each divided into areas of sleep quality, sleep latency, duration, efficiency, disturbance, use of medication, and daytime dysfunction. Each area is scored 0-3 points and the total is 0-21. A score greater than five indicates sleep disorder. The PSQI was surveyed during hospitalization and three months after surgery for post-fracture sleep status. To analyze changes before and after the fracture, paired T-tests and chi-square tests were performed. Results: From August 2022 to January 2023, a total of 40 patients who were recruited into the REAL Hip Cohort responded to the PSQI survey. The average age was 77.4 years and 36 were female. Sleep quality worsened from 0.75 ± 1.0 before surgery to 1.4 ± 1.0 three months after surgery (p = 0.019), and sleep efficiency also worsened from 0.4 ± 0.6 to 1.4 ± 1.0 (p < 0.001). The PSQI increased from an average of 5.2 ± 2.8 before surgery to 8.2 ± 4.2 three months after surgery (p = 0.007), and the number of patients who could be diagnosed with sleep disorders also increased from 12 (40%) to 24 (60%) (p = 0.030). Conclusions: A decline in overall sleep status was observed in patients in a survey on sleep patterns three months after hip fracture. Additional management is needed to improve their sleep patterns.


Assuntos
Fraturas do Quadril , Transtornos do Sono-Vigília , Humanos , Feminino , Idoso , Masculino , Qualidade do Sono , Qualidade de Vida , Inteligência Artificial , Fraturas do Quadril/complicações , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/cirurgia , Sono , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/etiologia
3.
Toxicology ; 496: 153618, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37611816

RESUMO

With its increasing value as a means of public transportation, the health effects of the air in subway stations have attracted public concern. In the current study, we investigated the pulmonary toxicity of dust collected from an air purifier installed on the platform of the busiest subway station in Seoul. We found that the dust contained various elements which are attributable to the facilities and equipment used to operate the subway system. Particularly, iron (Fe), chromium (Cr), zirconium (Zr), barium (Ba), and molybdenum (Mo) levels were more notable in comparison with those in dust collected from the ventilation chamber of a subway station. To explore the health effects of inhaled dust, we first instilled via the trachea in ICR mice for 13 weeks. The total number of pulmonary macrophages increased significantly with the dose, accompanying hematological changes. Dust-laden alveolar macrophages and inflammatory cells accumulated in the perivascular regions in the lungs of the treated mice, and pulmonary levels of CXCL-1, TNF-α, and TGF-ß increased clearly compared with the control. The CCR5 and CD54 level expressed on BAL cell membranes was also enhanced following exposure to dust, whereas the CXCR2 level tended to decrease in the same samples. In addition, we treated the dust to alveolar macrophages (known as dust cells), lysosomal and mitochondrial function decreased, accompanied by cell death, and NO production was rapidly elevated with concentration. Moreover, the expression of autophagy- (p62) and anti-oxidant (SOD-2)-related proteins increased, and the expression of inflammation-related genes was dramatically up-regulated in the dust-treated cells. Therefore, we suggest that dysfunction of alveolar macrophages may importantly contribute to dust-induced inflammatory responses and that the exposure concentrations of Cr, Fe, Mo, Zr, and Ba should be considered carefully when assessing the health risks associated with subway dust. We also hypothesize that the bound elements may contribute to dust-induced macrophage dysfunction by inhibiting viability.


Assuntos
Pneumonia , Ferrovias , Animais , Camundongos , Camundongos Endogâmicos ICR , Macrófagos Alveolares , Pneumonia/induzido quimicamente , Poeira
4.
Artigo em Inglês | MEDLINE | ID: mdl-36078648

RESUMO

The purpose of this study was to analyze the effect of real-time online Pilates exercise during COVID-19 on women's body composition, blood lipids, and psychological health after childbirth. The participants were 16 pregnant women (24-28 weeks pregnant) enrolled at the C Women's Culture Center in Seoul, South Korea, classified into online Pilates groups and non-exercise groups (PE, n = 8; CON, n = 8). The online Pilates program was conducted for 8 weeks, twice a week, and 50 min a day using a real-time video chat app. Participants visited the hospital twice for body composition and blood tests. Questionnaires on postpartum depression, sleep disorder, and stress were conducted at 6 weeks and 12 weeks after childbirth. We found a significant difference between groups in body composition. The weight, percentage of body fat, body fat mass, and BMI of the PE group decreased. Blood lipids showed significant differences between the groups in TC, TG, LDL and CRP, while insulin and HDL showed no difference. All blood lipids, insulin, and CRP in the PE group were reduced. There were significant differences between the groups in postpartum depression, sleep disorders, and perceived stress indices performed in the post-test, and the serotonin concentration in the PE group increased. Serotonin levels were significantly correlated with postpartum depression, body fat mass, and body fat rate. Pregnant women's online Pilates in this study was effective at reducing weight and depression in women after childbirth and should be used to promote women's mental health during COVID-19.


Assuntos
COVID-19 , Depressão Pós-Parto , Insulinas , Transtornos do Sono-Vigília , Índice de Massa Corporal , Feminino , Humanos , Lipídeos , Projetos Piloto , Gravidez , Gestantes , Serotonina
5.
Artigo em Inglês | MEDLINE | ID: mdl-36613048

RESUMO

The purpose of this study was to identify the ego-resiliency of Taekwondo athletes and to develop a scale measuring such skills. We collected preliminary data using an open-ended online survey targeting Taekwondo athletes from nine countries (South Korea, China, Malaysia, United States, Spain, France, Brazil, United Kingdom, and Taiwan) who participated in international competitions between 2019 and 2020. We extracted participants' ego-resiliency from 48 survey responses, guided by expert meetings and a thorough literature review. We verified our Taekwondo ego-resiliency scale's construct validity using 741 survey responses. We utilized V coefficients, parallel analysis, an exploratory structural equation model, maximum likelihood, confirmatory factor analysis, and multi-group confirmatory factor analysis for data analysis. We identified four core ego-resiliency types: "empathy," "coach support," "care," and "parent support/effort". Our final measure, which demonstrated evidence of reliability and validity, comprises 18 items spanning 4 factors, with each item rated on a 3-point Likert scale.


Assuntos
Artes Marciais , Humanos , Reprodutibilidade dos Testes , Inquéritos e Questionários , República da Coreia , Análise Fatorial , Psicometria
6.
Int J Mol Sci ; 22(8)2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33920210

RESUMO

Peppers (Capsicum annuum L.) are the most widespread and cultivated species of Solanaceae in subtropical and temperate countries. These vegetables are economically attractive worldwide. Although whole-genome sequences of peppers and genome-editing tools are currently available, the precision editing of peppers is still in its infancy because of the lack of a stable pepper transformation method. Here, we employed three Agrobacterium tumefaciens strains-AGL1, EHA101, and GV3101-to investigate which Agrobacterium strain could be used for pepper transformation. Hot pepper CM334 and bell pepper Dempsey were chosen in this study. Agrobacterium tumefaciens GV3101 induced the highest number of calli in cv. Dempsey. All three strains generated similar numbers of calli for cv. CM334. We optimized a suitable concentration of phosphinothricin (PPT) to select a CRISPR/Cas9 binary vector (pBAtC) for both pepper types. Finally, we screened transformed calli for PPT resistance (1 and 5 mg/L PPT for cv. CM334 and Dempsey, respectively). These selected calli showed different indel frequencies from the non-transformed calli. However, the primary indel pattern was consistent with a 1-bp deletion at the target locus of the C. annuumMLO gene (CaMLO2). These results demonstrate the different sensitivity between cv. CM334 and Dempsey to A. tumefaciens-mediated callus induction, and a differential selection pressure of PPT via pBAtC binary vector.


Assuntos
Agrobacterium/genética , Capsicum/genética , Edição de Genes/métodos , Plantas Geneticamente Modificadas/genética , Capsicum/crescimento & desenvolvimento , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/crescimento & desenvolvimento
7.
J Nanosci Nanotechnol ; 20(12): 7724-7729, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711649

RESUMO

Despite the fact that stability is a critical issue affecting halide perovskite after the materials have been developed, these materials continue to be studied due to their outstanding optoelectronic characteristics such as narrow emission band width, high PLQY. Many methods are suggested and improved, but the limitations for the display and lighting applications are still remaining. Here, we propose the fabrication of stable cesium lead tri-halide (CsPbX3; X= Cl, Br, I) perovskite films using photocurable polyurethane material, norland optical adhesive 63 (NOA 63), to generate white LEDs by placing films on the InGaN 450 nm blue chip. Comparing with the conventional perovskites, fabricated films well maintained the luminescence properties such as full widths at half maximum (FWHM) of 18 nm and 31 nm for green and red films, respectively. For the stability issue, pristine perovskite without encapsulation is decomposed immediately at high humidity and temperature, but NOA 63 encapsulated perovskite maintained a PL emission property of 60% after four hours in artificial atmosphere. The CIE color triangle reached ~119% of the NTSC standard, exhibiting high color purity. From the results, we confirm that the NOA 63 encapsulated halide perovskites are beneficial when applied in optoelectronic applications due to their improved stability and maintained characteristics.

8.
Appl Psychophysiol Biofeedback ; 45(3): 211-220, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32347399

RESUMO

Real-time biofeedback is a promising post-stroke gait rehabilitation strategy that can target specific gait deficits preferentially in the paretic leg. Our previous work demonstrated that the use of an audiovisual biofeedback interface designed to increase paretic leg propulsion, measured via anterior ground reaction force (AGRF) generation during late stance phase of gait, can induce improvements in peak AGRF production of the targeted and paretic limb of able-bodied and post-stroke individuals, respectively. However, whether different modes of biofeedback, such as visual, auditory, or a combination of both, have differential effects on AGRF generation is unknown. The present study investigated the effects of audio only, visual only, or audiovisual AGRF biofeedback in able-bodied and post-stroke individuals. Seven able-bodied (6 females, 27 ± 2 years) and nine post-stroke individuals (6 females, 54 ± 12 years, 42 ± 26 months post-stroke) completed four 30-s walking trials on a treadmill under 4 conditions: no biofeedback, audio biofeedback, visual biofeedback, or audiovisual biofeedback. Compared to walking without biofeedback, all three biofeedback modes significantly increased peak AGRF in the targeted and paretic leg. There was no significant difference in peak AGRF between the three biofeedback modes. Able-bodied individuals demonstrated greater feedback-induced increase in stride-to-stride variation of AGRF generation during audio biofeedback compared to visual biofeedback; however, similar results were not observed in the post-stroke group. The present findings may inform future development of real-time gait biofeedback interfaces for use in clinical or community environments.


Assuntos
Percepção Auditiva/fisiologia , Biorretroalimentação Psicológica/métodos , Fenômenos Biomecânicos/fisiologia , Transtornos Neurológicos da Marcha/reabilitação , Marcha/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Percepção Visual/fisiologia , Adulto , Idoso , Retroalimentação Sensorial/fisiologia , Feminino , Transtornos Neurológicos da Marcha/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Resultado do Tratamento
9.
Tuberc Respir Dis (Seoul) ; 81(4): 339-346, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29926557

RESUMO

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a standard procedure to evaluate suspicious lymph node involvement of lung cancer because computed tomography (CT) and 18F-fluorodeoxyglucose positron emission tomography-CT (PET-CT) have limitations in their sensitivity and specificity. There are a number of benign causes of false positive lymph node such as anthracosis or anthracofibrosis, pneumoconiosis, old or active tuberculosis, interstitial lung disease, and other infectious conditions including pneumonia. The purpose of this study was to evaluate possible causes of false positive lymph node detected in chest CT or PET-CT. METHODS: Two hundred forty-seven patients who were initially diagnosed with lung cancer between May 2009 and December 2012, and underwent EBUS-TBNA to confirm suspicious lymph node involvement by chest CT or PET-CT were analyzed for the study. RESULTS: Of 247 cases, EBUS-TBNA confirmed malignancy in at least one lymph node in 189. The remaining 58 patients whose EBUS-TBNA results were negative were analyzed. Age ≥65, squamous cell carcinoma as the histologic type, and pneumoconiosis were related with false-positive lymph node involvement on imaging studies such as chest CT and PET-CT. CONCLUSION: These findings suggest that lung cancer staging should be done more carefully when a patient has clinically benign lymph node characteristics including older age, squamous cell carcinoma, and benign lung conditions.

10.
ACS Appl Mater Interfaces ; 9(30): 25257-25264, 2017 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-28700209

RESUMO

Thin films of a heteropolytungstate, lithium silicotungstate (Li4SiW12O40, termed Li-ST), prepared by a solution process at low temperature, were successfully applied as electron transporting layer (ETL) of planar-type perovskite solar cells (PSCs). Dense and uniform Li-ST films were prepared on FTO glass by depositing a thin Li-ST buffer layer, followed by coating of a main Li-ST layer. The film thickness was controlled by varying the number of coating cycles, consisting of spin-coating and thermal treatment at 150 °C. In particular, by employing 60 nm-thick Li-ST layer obtained by two cycles of coating, the fabricated CH3NH3PbI3 PSC device demonstrates the photovoltaic conversion efficiency (PCE) of 14.26% with JSC of 22.16 mA cm-2, VOC of 0.993 mV and FF of 64.81%. The obtained PCE is significantly higher than that of the PSC employing a TiO2 layer processed at the same temperature (PCE = 12.27%). Spectroscopic analyses by time-resolved photoluminescence and pulsed light-induced transient measurement of photocurrent indicate that the Li-ST layer collects electrons from CH3NH3PbI3 more efficiently and also exhibits longer electron lifetime than the TiO2 layer thermally treated at 150 °C. Thus, Li-ST is considered to be a promising ETL material that can be applied for the fabrication of flexible PSC devices.

11.
J Nanosci Nanotechnol ; 17(1): 530-37, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29629744

RESUMO

We report the synthesis and optoelectronic properties of novel platinum-based polymers (p-Pt-DPP) incorporating 3,6-di-2-thienyl-2,5-dihydro-2,5-diethylhexylpyrrolo[3,4-c]pyrrole-1,4-dione. The synthesized amorphous metallated polymer exhibited long wavelength absorption in the range of 500­684 nm and a band-gap as low as 1.75 eV. Organic field-effect transistors (OFETs) fabricated from p-Pt-DPP showed hole mobility of 1.6 × 10⁻³ cm² · V⁻¹s⁻¹ and an on/off ratio of 5 × 104. In addition, polymer solar cells (PSCs) based on p-Pt-DPP and PC71BM exhibited a photovoltaic efficiency of 1.22% under AM 1.5 G conditions with an illumination of 100 mW·cm−2 without any annealing process.

12.
PLoS One ; 11(12): e0168632, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28036342

RESUMO

Hypoxia in the tumor microenvironment is the leading factor in angiogenesis. Angiogenesis can be identified by dynamic contrast-enhanced breast MRI (DCE MRI). Here we investigate the relationship between perfusion parameters on DCE MRI and angiogenic and prognostic factors in patients with invasive ductal carcinoma (IDC). Perfusion parameters (Ktrans, kep and ve) of 81 IDC were obtained using histogram analysis. Twenty-fifth, 50th and 75th percentile values were calculated and were analyzed for association with microvessel density (MVD), vascular endothelial growth factor (VEGF) and conventional prognostic factors. Correlation between MVD and ve50 was positive (r = 0.33). Ktrans50 was higher in tumors larger than 2 cm than in tumors smaller than 2 cm. In multivariate analysis, Ktrans50 was affected by tumor size and MVD with 12.8% explanation. There was significant association between Ktrans50 and tumor size and MVD. Therefore we conclude that DCE MRI perfusion parameters are potential imaging biomarkers for prediction of tumor angiogenesis and aggressiveness.


Assuntos
Biomarcadores/metabolismo , Meios de Contraste/administração & dosagem , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Adulto , Idoso , Carcinoma Ductal/metabolismo , Carcinoma Ductal/patologia , Humanos , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Perfusão/métodos , Prognóstico , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
J Nanosci Nanotechnol ; 15(8): 5942-5, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26369176

RESUMO

Electron beam (e-beam) irradiation of polyacrylonitrile (PAN) was performed to investigate the effects of radiation on the electrospinning process. For this study, polyacrylonitrile powder was subjected to e-beam irradiation with different doses of up to 100 kGy under an N2 atmosphere. Polymer solutions were prepared by dissolving PAN in N,N-dimethyl-formamide (DMF) at a 1:9 ratio by weight. The prepared PAN/DMF solutions showed different colors with different e-beam doses. The resulting structures in solutions contained conjugated C=N bonds, which caused the observed color formation. In addition, the conductivity of the PAN/DMF solution increased with an increase in e-beam irradiation dose. In the DSC spectra of electrospun PAN fibers, the peak temperature of the exothermic reactions was observed to decrease with an increase in the e-beam irradiation strength.

14.
J Nanosci Nanotechnol ; 15(8): 6028-31, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26369192

RESUMO

Carbon materials containing magnetic nanopowder have been attractive in technological applications such as electrochemical capacitors and electromagnetic wave shielding. In this study, polyacrylonitrile (PAN) fibers containing nickel nanoparticles were prepared using an electrospinning method and thermal stabilization. The reduction of nickel oxide was investigated under a nitrogen atmosphere within a temperature range of 600 to 1,000 °C. Carbon nanofibers containing nickel nanoparticles were characterized by FE-SEM, EDS, XRD, TGA, and VSM. It was found that nickel nanoparticles were formed by a NiO reduction in PAN as a function of the thermal treatment. These results led to an increase in the coercivity of nanofibers and a decrease in the remanence magnetization.


Assuntos
Resinas Acrílicas/química , Nanofibras/química , Nanofibras/ultraestrutura , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Níquel/química , Impedância Elétrica , Calefação/métodos , Campos Magnéticos , Teste de Materiais , Oxirredução , Tamanho da Partícula , Propriedades de Superfície
15.
Int J Stem Cells ; 7(2): 63-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25473443

RESUMO

BACKGROUND AND OBJECTIVES: Stem cell-based therapy is a potential new approach in the treatment of stroke. However, the efficacy and safety of these treatments are not yet fully understood. Therefore, we performed a meta-analysis of available single-arm studies using stem cell-based therapy in patients with stroke. METHODS: We searched MEDLINE, EMBASE, and the Cochrane database for studies of stem cell therapy in patients with stroke from its inception through July 2014. The articles included in the search were restricted to the English language, studies with at least 5 patients, and those using cell-based therapies for treating stroke. RESULTS: Fourteen studies included in the meta-analysis. The pooled mean difference in National Institutes of Health Stroke Scale (NIHSS) scores from baseline to follow-up points was 5.7 points (95%CI: -8.2 to -3.2, I(2) =91.5%) decreased. Also the pooled mean difference in modified Bathel index (BI) score was increased by 31.5 points (95%CI: 35.6∼14.9, I(2) =52.7%) and the pooled incidence rate to achieve on modified Rankin score (mRS)≤2 was 40% (95% CI: 30%∼51%, I(2) =35.4%) at follow-up points. The pooled incidence rates of death, seizure, and infection were 13% (95%CI, 8∼23%), 15% (95%CI, 8∼25%), and 15% (95%CI, 8∼23%), respectively. CONCLUSIONS: The published data suggest that stem cell-based therapy for patients with stroke can be judged as effective based on single arm clinical studies. However, clinical benefits of stem cell therapy for patients with stroke need further investigation and reevaluation to test the clinical efficacy.

16.
J Nanosci Nanotechnol ; 13(11): 7358-64, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24245255

RESUMO

In order to overcome the difficulty of dispersion and low conductivity in composite containing graphene, graphene oxide (GO) has been used instead of neat graphene. And the GO treated by radiation, could give improved conductivity of the GO-containing polymer composite. In this study, fluorene based water-soluble conjugated polymer (WPF-6-oxy-F) was introduced in GO solution to investigate the change of optical and electrical properties through radiation process. UV-Vis absorption of irradiated WPF-6-oxy-F-GO composite was red shifted and I(D)/I(G) ratio of Raman spectra decreased. XPS analysis showed that C-N bonds was formed after the irradiation and confirmed the increased bonds between the GO and the water-soluble conjugated polymer matrix. From the AFM and XPS analysis, it was found that the water-soluble conjugated polymer matrix was stacked between the modified GO in the morphology of irradiated WPF-6-oxy-F-GO composite was increased after gamma ray irradiation up to 10(-2) S/cm.


Assuntos
Grafite/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Óxidos/química , Polímeros/química , Água/química , Condutividade Elétrica , Grafite/efeitos da radiação , Teste de Materiais , Nanoestruturas/efeitos da radiação , Óxidos/efeitos da radiação , Tamanho da Partícula , Polímeros/efeitos da radiação , Doses de Radiação , Refratometria , Solubilidade
17.
Stem Cell Res Ther ; 4(4): 82, 2013 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-23849537

RESUMO

INTRODUCTION: Although blinding is a methodologic safeguard to ensure obtaining comparability of groups in a clinical trial, it is very difficult to maintain blinding from the beginning to the end of a study. The aim of the study was to see how proper blinding of both participants and treatment providers from the planning phase of the study to during the study affected the study outcomes. METHODS: We searched Medline, EMBASE, and Cochrane databases from inception to November 2011. The studies included in this review were randomized controlled trials, with acute myocardial infarction (AMI) patients who received percutaneous coronary intervention (PCI), intracoronary (IC) infusion of autologous bone marrow stem cells (BMSCs), unselected BMSCs, 10(8) or more cell dose, and up to 6-month follow-up periods. RESULTS: The initial search identified 881 references, of which 17 references were eligible for inclusion. Six of 17 trials isolated cells directly from bone marrow by aspiration in the control group as well as in the BMSC group. Nine of 17 trials underwent both cardiac catheterization and an identical injection procedure on the control group as well as the BMSC group. Compared with the control group, BMSC transplantation improved left ventricular ejection fraction (LVEF) by 2.51 (95% CI, 1.20 to 3.83; P = 0.0002; I(2) = 75%) at 6 months. In the present results, the studies that did not perform bone marrow aspiration in the control group showed significant improvement in LVEF by 3.81% (95% CI, 2.44 to 5.17), whereas no significant treatment effect was found in the studies in which the control group underwent bone marrow aspiration, as indicated the LVEF change of -1.29% (95% CI, 4.15 to 1.58). The trials that did not conduct catheterization on control subjects showed significant LVEF changes (4.45%; 95% CI, 2.48 to 6.43); however, those with cardiac catheterization as a sham procedure on the control group did not show significant changes in LVEF at 6 months (0.92%; 95% CI, -0.61 to 2.44). CONCLUSIONS: Unblinding might be overestimating the treatment effect. These findings suggest that randomized controlled trials testing the efficacy of BMSC therapy should be appropriately designed and rigorously applied to avoid bias.


Assuntos
Transplante de Medula Óssea/métodos , Transplante Autólogo/métodos , Doença Aguda , Feminino , Humanos , Masculino , Infarto do Miocárdio/cirurgia , Projetos de Pesquisa
18.
J Nanosci Nanotechnol ; 12(7): 6120-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22966719

RESUMO

The aim of this study was to evaluate the ability of electron beam irradiation to drive stabilization reactions within PAN nanofiber mats to obtain carbon nanofiber mats. PAN nanofiber mats with fiber diameters of 300-400 nm were prepared via an electrospinning method. Electrospun PAN nanofiber mats were stabilized by electron beam irradiation with various doses up to 5,000 kGy. Using the irradiation-stabilized PAN nanofiber mats, carbon nanofibers were obtained by pyrolysis in a tube furnace for 1 h at 1,000 degrees C under an N2 atmosphere. FT-IR analysis indicated that the transformation of C[triple bond]N groups to C==N groups was accelerated by electron beam stabilization. The thermal behavior of the PAN nanofiber mats was studied using DSC and TGA. DSC thermograms showed that the peak temperatures of the exothermic reactions were found to decrease with increasing electron beam irradiation doses. Irradiation-stabilized PAN nanofiber mats were not observed to dramatically decrease in weight between 290 degrees C and 320 degrees C, an observation presumed to be related to cyclization. The char yields of PAN were found to increase with increasing irradiation doses.

19.
J Nanosci Nanotechnol ; 10(1): 74-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20352813

RESUMO

Composites of Fe93.5Si6.5 powder and epoxy (diglycidyl ether of bisphenol A type) were prepared using an electron beam irradiation process. Scanning electron microscope (SEM), vibrating sample magnetometer (VSM) and network analyzer were used to analyze the structure, electromagnetic properties and micro wave absorption of the composites. Results show that the saturation magnetization depends on the fraction of the Fe93.5Si6.5 powder in the composite, which affects initial permeability. It is believed that the eddy current loss is a dominant factor over 1 GHz and that the resonance frequency of the composite decreases with increasing fractions of Fe93.5Si6.5 powder. Finally, reflection loss was calculated from the permeability and permittivity of these composites. Composite with 50 wt% Fe93.5Si6.5 powder fractions and 5 mm thickness showed reflection loss below -20 dB from 3.66 GHz to 4.16 GHz. Therefore, it is believed that thin Fe-Si/epoxy composites may be a good candidate for microwave absorption application.

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