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1.
Bioinspir Biomim ; 14(2): 026005, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30616229

RESUMO

We report on the development and analysis of a new torque-actuated dissipative spring loaded inverted pendulum model with rolling contact (TDR-SLIP), which is a successor to the previously developed spring loaded inverted pendulum model with rolling contact (R-SLIP) model. The stability properties of the models were analyzed numerically via steps-to-fall analysis and return map analysis, wherein the dimensionless parameters are varied to analyze their effects on the dynamic performance of the model, including torque, damping constant, spring constant, touchdown angle, touchdown speed, and landing angle. Because the involvement of torque and damping in the TDR-SLIP model is similar to other recently developed torque-actuated dissipative spring loaded inverted pendulum studies, their performance was compared so that the unique features of the TDR-SLIP model, such as rolling contact, could be investigated. To undertake the comparison, a method for yielding parameter equivalency between these two models is also reported. In addition to its analytical role, the TDR-SLIP model served as a template to initiate the stable running behavior of the empirical robot acted as the anchor. Two sets of legs were evaluated-the original compliant half-circular leg of the robot and the new mechanical legs, which resemble the morphology of the TDR-SLIP model. Two types of control strategies were tested-position-based control and hybrid control. The experimental results reveals that the low-damped compliant half-circular leg and the mechanical leg match the behaviors of the R-SLIP model and the TDR-SLIP model, respectively, and the robot with hybrid control performs more stably and more closely to the model profile. In addition, when the robot's motion follows the template's stable dynamics, the energy cost of the leg in stance can be significantly lower than that in flight.


Assuntos
Biomimética/instrumentação , Insetos/fisiologia , Robótica/instrumentação , Corrida/fisiologia , Voo Espacial/instrumentação , Animais , Fenômenos Biomecânicos/fisiologia , Extremidades/fisiologia , Voo Animal/fisiologia , Modelos Biológicos , Torque
2.
Artigo em Inglês | MEDLINE | ID: mdl-30442545

RESUMO

This study investigates spatiotemporal gait adjustments that occur while stepping over virtual obstacles during treadmill walking in people with/without diabetic peripheral neuropathy (DPN). Eleven adults with Type 2 diabetes mellitus, ten DPN, and 11 age-matched healthy adults (HTY) participated in this study. They stepped over forthcoming virtual obstacles during treadmill walking. Outcomes such as success rate, spatiotemporal gait characteristics during obstacle crossing, and correlations between these variables were evaluated. The results partially supported our hypotheses that when comparing with HTY and DM, people with DPN adopted a crossing strategy which decreased obstacle crossing success rate and maximal toe elevation, and increased stride time and stance time during virtual obstacle crossing. This might be due to the compromised somatosensory functions of their lower extremity which may increase the risk of falling. This study also found an inter-leg relationship which may be applied to future stepping or obstacle crossing training that incorporates both legs as a means for improving outcomes of the trailing leg during daily obstacle negotiation.

3.
Surg Endosc ; 2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30341653

RESUMO

BACKGROUND: Our aim was to determine how objectively-measured and self-reported muscle effort and fatigue of the upper-limb differ between surgeons performing laparoscopic (LAP) and robotic-assisted (ROBOT) surgeries. METHODS: Surgeons performing LAP or ROBOT procedures at a single-institution were enrolled. Objective muscle activation and self-reported fatigue were evaluated, and comparisons were made between approaches. Muscle activation of the upper trapezius (UT), anterior deltoid (AD), flexor carpi radialis (FCR), and extensor digitorum (ED) were recorded during the surgical procedure using Trigno wireless surface electromyography (EMG). The maximal voluntary contraction (MVC) was obtained to normalize root-mean-square muscle activation as %MVCRMS. The median frequency (MDF) was calculated to assess muscle fatigue. Each surgeon also completed the validated Piper Fatigue Scale-12 (PFH-12) before and after the procedure for self-perceived fatigue assessment. Statistical analysis was done using SAS/STAT software, with α = 0.05. RESULTS: 28 surgeries were recorded (LAP: N = 18, ROBOT: N = 10). EMG analysis revealed the ROBOT group had a higher muscle activation than LAP for UT (37.7 vs. 25.5, p = 0.003), AD (8.9 vs. 6.3, p = 0.027), and FCR (14.4 vs. 10.9, p = 0.019). Conversely, LAP required more effort for the ED, represented by a significantly lower MDF compared to the ROBOT group (91.2 ± 1.5 Hz vs. 102.8 ± 1.5 Hz, p < 0.001). Survey analysis revealed no differences in self-reported fatigue before and after the surgery between approaches, p = 0.869. CONCLUSIONS: Our analysis revealed surgeons show similar fatigue levels performing the first case of the day using either robotic or LAP surgery. Surgeons performing LAP surgery had more fatigue in the forearm, robotic surgery required more shoulder and neck use, but neither was superior. Neither technique produced significant overall fatigue on survey. Long-term selective use of these different muscles could be correlated with different patterns of injury. Future studies are needed to fully understand long-term implications of prolonged surgery on occupational injury.

4.
JACC Basic Transl Sci ; 3(4): 503-517, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30175274

RESUMO

Heart failure remains a major cause of morbidity and mortality in developed countries. There is still a strong need to devise new mechanism-based treatments for heart failure. Numerous studies have suggested the importance of the Ca2+-dependent protease calpain in cardiac physiology and pathology. However, no drugs are currently under development or testing in human patients to target calpain for heart failure treatment. Herein the data demonstrate that inhibition of calpain activity protects against deleterious ultrastructural remodeling and cardiac dysfunction in multiple rodent models of heart failure, providing compelling evidence that calpain inhibition is a promising therapeutic strategy for heart failure treatment.

5.
Appl Radiat Isot ; 137: 73-79, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29587162

RESUMO

TLD-400 (CaF2:Mn) chips were applied for the gamma-ray dose measurement in a PMMA phantom exposed to a BNCT beam because of their very low neutron sensitivity. Since TLD-400 chips possess an adequate amount of Mn activator they have been employed in this work simultaneously for neuron activation measurement. The self-irradiation TL signals owing to the decay of the neutron induced 56Mn activity have been applied for a calibration of the TLD-400 chip in situ, where the activities were measured by an HPGe detector system and the energy deposition per disintegration of 56Mn was calculated by applying a Monte Carlo code. It was accidentally found that the irradiated TLD-400 chips were capable of emitting prominent scintillation lights owing to the induced 56Mn activity, which can easily be recorded by the TLD reader without heating and after a calibration can be used to determine the 56Mn activity.


Assuntos
Terapia por Captura de Nêutron de Boro , Dosimetria Termoluminescente/métodos , Terapia por Captura de Nêutron de Boro/normas , Calibragem , Raios gama , Humanos , Manganês/análise , Manganês/efeitos da radiação , Método de Monte Carlo , Nêutrons , Imagens de Fantasmas , Controle de Qualidade , Radioisótopos/análise , Dosagem Radioterapêutica , Contagem de Cintilação , Dosimetria Termoluminescente/instrumentação , Dosimetria Termoluminescente/estatística & dados numéricos
6.
J Nucl Cardiol ; 2018 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-29484543

RESUMO

BACKGROUND: The benefits of attenuation correction (AC) in technetium-99m myocardial perfusion imaging (MPI) have been well established. However, the value of thallium (Tl-201) AC and routine computed tomography AC (CTAC) were less well established. The aims of this study were to evaluate the diagnostic performance of thallium (Tl-201) MPI with additional CTAC and to determine which participants would benefit most. METHODS AND RESULTS: A total of 108 consecutive patients who underwent Tl-201 MPI and received coronary angiography within 3 months were enrolled. Diagnostic performance was determined by sensitivity, specificity, and receiver operating characteristic curve analysis. Subgroup analyses were performed using gender and obesity. CTAC improved the area under the curve (0.84 vs. 0.77, P = 0.037 at patient level), primarily due to a significant improvement in specificity (0.78 vs. 0.57, P = 0.013) and no significant difference in sensitivity (0.79 vs. 0.82, P = 0.75). In subgroup analysis, CTAC was most helpful in obese subjects, men, and especially right coronary artery lesions. CONCLUSIONS: CTAC significantly improved diagnostic performance primarily by increasing the specificity, and the improvements were significantly greater in obese patients and male patients. These findings suggest that CTAC should be applied to Tl-201 MPI as routine clinical practice.

7.
J Mol Cell Cardiol ; 115: 104-114, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29307535

RESUMO

AIMS: Protein kinase C (PKC) isozymes contribute to the development of heart failure through dysregulation of Ca2+ handling properties and disruption of contractile function in cardiomyocytes. However, the mechanisms by which PKC activation leads to Ca2+ dysfunction are incompletely understood. METHODS AND RESULTS: Shortly upon ventricular pressure overload in mice, we detected transient PKC activation that was associated with pulsed actin cytoskeletal rearrangement. In cultured cardiomyocytes, transient activation of PKC promoted long-term deleterious effects on the integrity of the transverse (T)- tubule system, resulting in a significant decrease in the amplitude and increase in the rising kinetics of Ca2+ transients. Treatment with a PKCα/ß inhibitor restored the synchronization of Ca2+ transients and maintained T-tubule integrity in cultured cardiomyocytes. Supporting these data, PKCα/ß inhibition protected against T-tubule remodeling and cardiac dysfunction in a mouse model of pressure overload-induced heart failure. Mechanistically, transient activation of PKC resulted in biphasic actin cytoskeletal rearrangement, consistent with in vivo observations in the pressure overloaded mouse model. Transient inhibition of actin polymerization or depolymerization resulted in severe T-tubule damage, recapitulating the T-tubule damage induced by PKC activation. Moreover, inhibition of stretch activated channels (SAC) protected against T-tubule remodeling and E-C coupling dysfunction induced by transient PKC activation and actin cytoskeletal rearrangement. CONCLUSIONS: These data identify a key mechanistic link between transient PKC activation and long-term Ca2+ handling defects through PKC-induced actin cytoskeletal rearrangement and resultant T-tubule damage.

8.
Mol Genet Metab ; 123(2): 140-147, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28615118

RESUMO

Fabry disease is an X-linked disorder resulted from deficiency of α-galactosidase A (GLA) activity. In Taiwan, a total of 792,247 newborns were screened from 2008 to 2014 in two newborn screening centers, and 13 variants of uncertain significance (VOUS) in the GLA gene were identified. To determine whether these variants were pathogenic or not, functional, biochemical, clinical and pedigree analyses were performed. In vitro functional assay was established through site-directed mutagenesis, and four in silico tools were used to predict pathogenesis. The enzyme activity of dried blood spots and plasma metabolite lyso-Gb3 level from subjects with the variants were measured. Additionally, clinical manifestations were evaluated extensively from the subjects and their relatives. Our results revealed that p.G104V, p.I232T, p.D322H, and p.G360C all exhibited relatively low residual enzyme activities and elevated plasma lyso-Gb3 level. These data strongly suggest that these Fabry mutations may cause classical or later-onset phenotypes. In contrast, neither significantly clinical symptoms nor elevated lyso-Gb3 level was found in cases with p.P60S, p.A108T, p.S304T, p.R356Q, and p.P362T variants, which may be non-pathogenic or milder forms of Fabry variants. More data need to be included for the patients with p.N53D, p.P210S, p.M296L, and p.K391T variants. The established system provides us more information to classify these GLA variants.

9.
Clin Chem ; 63(7): 1271-1277, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28450385

RESUMO

BACKGROUND: Deficiency of the lysosomal enzyme acid α-glucosidase (GAA) causes Pompe disease. Newborn screening for Pompe disease is ongoing, and improved methods for distinguishing affected patients from those with pseudodeficiency, especially in the Asian population, would substantially reduce the number of patient referrals for clinical follow-up. METHODS: We measured the enzymatic activity of GAA in dried blood spots on newborn screening cards (DBS) using a tandem mass spectrometry (MS/MS) assay. The assay displayed a relatively large analytical range compared to the fluorimetric assay with 4-methylumbelliferyl-α-glucoside. DBS from newborns confirmed to have infantile-onset Pompe disease (IOPD, n = 11) or late-onset Pompe disease (LOPD) (n = 12) and those from patients bearing pseudodeficiency alleles with or without Pompe mutations, or Pompe disease carriers (n = 230) were studied. RESULTS: With use of the MS/MS GAA assay in DBS, 96% of the pseudodeficiency newborns and all of the Pompe disease carriers were well separated from the IOPD and LOPD newborns. The fluorimetric assay separated <10% of the pseudodeficiencies from the IOPD/LOPD group. CONCLUSIONS: The relatively large analytical range MS/MS GAA assay but not the fluorimetric assay in DBS provides a robust approach to reduce the number of referrals and should dramatically facilitate newborn screening of Pompe disease.


Assuntos
Fluorometria , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Diagnóstico Pré-Natal , Espectrometria de Massas em Tandem , Humanos , Recém-Nascido , alfa-Glucosidases/sangue , alfa-Glucosidases/deficiência
10.
Nat Commun ; 8: 14706, 2017 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-28281525

RESUMO

Adipocytes are the most abundant stromal partners in breast tissue. However, the crosstalk between breast cancer cells and adipocytes has been given less attention compared to cancer-associated fibroblasts. Here we find, through systematic screening, that primary mammary gland-derived adipocytes (MGDAs) promote growth of breast cancer cells that express monocarboxylate transporter 2 (MCT2) both in vitro and in vivo. We show that ß-hydroxybutyrate is secreted by MGDAs and is required to enhance breast cancer cells malignancy in vitro. Consistently, ß-hydroxybutyrate is sufficient to promote tumorigenesis of a mouse xenograft model of MCT2-expressing breast cancer cells. Mechanistically we observe that upon co-culturing with MGDAs or treatment with ß-hydroxybutyrate, breast cancer cells expressing MCT2 increase the global histone H3K9 acetylation and upregulate several tumour-promoting genes. These results suggest that adipocytes promote malignancy of MCT2-expressing breast cancer via ß-hydroxybutyrate potentially by inducing the epigenetic upregulation of tumour-promoting genes.


Assuntos
Ácido 3-Hidroxibutírico/metabolismo , Adipócitos/metabolismo , Neoplasias da Mama/metabolismo , Epigênese Genética , Histonas/genética , Transportadores de Ácidos Monocarboxílicos/genética , Ácido 3-Hidroxibutírico/farmacologia , Acetilação , Adipócitos/patologia , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Proteínas do Domínio Armadillo/genética , Proteínas do Domínio Armadillo/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Feminino , Glipicanas/genética , Glipicanas/metabolismo , Histonas/metabolismo , Humanos , Células MCF-7 , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Camundongos , Camundongos Endogâmicos NOD , Transportadores de Ácidos Monocarboxílicos/metabolismo , Transplante de Neoplasias , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Diester Fosfórico Hidrolases/genética , Diester Fosfórico Hidrolases/metabolismo , Cultura Primária de Células , Pirofosfatases/genética , Pirofosfatases/metabolismo , Receptores Acoplados a Proteínas-G/genética , Receptores Acoplados a Proteínas-G/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
11.
Exp Brain Res ; 235(4): 1185-1193, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28188327

RESUMO

Sensory feedback below the sole of the foot using sub-threshold mechanical noise significantly reduced postural sway in patients with diabetes and stroke. However, the effects of tactile parameters on walking are still elusive. Specifically, the effects of such parameters on human gait variability need to be studied because of possible rehabilitation outcomes in terms of bringing improvement in temporal and spatial gait parameters. The purpose of this study was to investigate whether different frequency and amplitude combinations of vibro-tactile stimulation of feet would affect stride-to-stride variability in healthy young adults. Ten healthy subjects walked on a treadmill at self-selected pace while wearing customized insoles fitted with tactors that vibrated at selected frequencies and amplitudes. The results show that the frequency manipulations of tactile stimulation altered the long-range correlations (LRCs) in stride length while amplitude manipulations affected the LRCs in stride interval without having any effect on the amount of gait variability. Our findings suggest that independent neural mechanisms may be responsible for coordinating LRCs of gait parameters in the spatial and temporal domains.


Assuntos
Retroalimentação Sensorial/fisiologia , Marcha/fisiologia , Tato/fisiologia , Caminhada/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Pé/inervação , Humanos , Masculino , Estatística como Assunto , Vibração , Escala Visual Analógica , Adulto Jovem
12.
Clin Chim Acta ; 466: 185-193, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28108302

RESUMO

BACKGROUND: Fabry disease is a lysosomal storage disorder with an incidence of 1:1600 for the late-onset IVS4+919G>A cardiac variant mutation in Taiwan. Signs and symptoms of this cardiac variant include left ventricular hypertrophy, mitral insufficiency and/or arrhythmias. The search for biomarkers that might predict the clinical outcomes and guide treatment options is important. We thus investigated relationships between Fabry disease biomarkers (such as globotriaosylceramide (Gb3), globotriaosylsphingosine (lyso-Gb3)/related analogues) and age, gender, enzyme activity, clinical manifestations and severity of the disease in these patients. METHOD: Urine and plasma biomarkers were analyzed using tandem mass spectrometry. A large cohort of 191 adult and pediatric Fabry patients carrying the IVS4+919G>A mutation was studied. Some patients were members of the same family. RESULTS: Our results show that the plasma lyso-Gb3 level, and urinary analogue levels of lyso-Gb3 at m/z (+16), (+34), and (+50) adjusted for gender and age had a positive association with the left ventricular mass index, and/or the Mainz Severity Score Index. CONCLUSIONS: It might thus be of particular interest to monitor children with high levels of these biomarkers, as part of a longitudinal study in order to determine if the excretion profile at a young age is predictive of the outcomes of disease severity in adulthood.


Assuntos
Doença de Fabry/sangue , Doença de Fabry/genética , Mutação , Índice de Gravidade de Doença , Adulto , Fatores Etários , Biomarcadores/sangue , Criança , Doença de Fabry/diagnóstico , Feminino , Glicolipídeos/análise , Glicolipídeos/sangue , Cardiopatias/genética , Humanos , Transtornos de Início Tardio/genética , Masculino , Fatores Sexuais , Esfingolipídeos/análise , Esfingolipídeos/sangue , Taiwan
13.
Plant Mol Biol ; 93(3): 299-311, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27866313

RESUMO

KEY MESSAGE: Sugar regulation of gene expression has profound effects at all stages of the plant life cycle. Although regulation at the transcriptional level is one of the most prominent mechanisms by which gene expression is regulated, only a few transcription factors have been identified and demonstrated to be involved in the regulation of sugar-regulated gene expression. OsMYBS1, an R1/2-type MYB transcription factor, has been demonstrated to be involved in sugar- and hormone-regulated α-amylase gene expression in rice. Arabidopsis contains two OsMYBS1 homologs. In the present study, we investigate MYBS1 and MYBS2 in sugar signaling in Arabidopsis. Our results indicate that MYBS1 and MYBS2 play opposite roles in regulating glucose and ABA signaling in Arabidopsis during seed germination and early seedling development. MYB proteins have been classified into four subfamilies: R2R3-MYB, R1/2-MYB, 3R-MYB, and 4R-MYB. An R1/2-type MYB transcription factor, OsMYBS1, has been demonstrated to be involved in sugar- and hormone-regulated α-amylase genes expression in rice. In this study, two genes homologous to OsMYBS1, MYBS1 and MYBS2, were investigated in Arabidopsis. Subcellular localization analysis showed that MYBS1 and MYBS2 were localized in the nucleus. Rice embryo transient expression assays indicated that both MYBS1 and MYBS2 could recognize the sugar response element, TA-box, in the promoter and induced promoter activity. mybs1 mutant exhibited hypersensitivity to glucose, whereas mybs2 seedlings were hyposensitive to it. MYBS1 and MYBS2 are involved in the control of glucose-responsive gene expression, as the mybs1 mutant displayed increased expression of a hexokinase gene (HXK1), chlorophyll a/b-binding protein gene (CAB1), ADP-glucose pyrophosphorylase gene (APL3), and chalcone synthase gene (CHS), whereas the mybs2 mutant exhibited decreased expression of these genes. mybs1 also showed an enhanced response to abscisic acid (ABA) in the seed germination and seedling growth stages, while mybs2 showed reduced responses. The ABA biosynthesis inhibitor fluridone rescued the mybs1 glucose-hypersensitive phenotype. Moreover, the mRNA levels of three ABA biosynthesis genes, ABA1, NCED9, and AAO3, and three ABA signaling genes, ABI3, ABI4, and ABI5, were increased upon glucose treatment of mybs1 seedlings, but were decreased in mybs2 seedlings. These results indicate that MYBS1 and MYBS2 play opposite roles in regulating glucose and ABA signaling in Arabidopsis during seed germination and early seedling development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Metabolismo dos Carboidratos , Transdução de Sinais , Fatores de Transcrição/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Metabolismo dos Carboidratos/efeitos dos fármacos , Metabolismo dos Carboidratos/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Teste de Complementação Genética , Germinação/efeitos dos fármacos , Glucose/farmacologia , Oryza/embriologia , Oryza/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Fatores de Transcrição/genética
14.
Int J Cardiol ; 227: 360-366, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27843048

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) have identified several loci associated with atrial fibrillation (AF) and have been reportedly associated with response to catheter ablation for AF in patients of European ancestry; however, associations between susceptibility loci and clinical recurrence of AF after catheter ablation have not been examined in Chinese Han populations. To the personalization of catheter ablation for AF, we examined whether these single nucleotide polymorphisms (SNPs) can predict clinical outcomes after catheter ablation for AF in Chinese Han population. METHODS AND RESULTS: The association between 8 SNPs and AF was studied in 1418 AF patients and 1424 controls by the unconditional logistic regression analysis. The survival analyses were used to compare AT/AF recurrence differences among 438 AF patients, which were classified by the genotype of rs2200733. rs2200733 and rs6590357 were significantly associated with AF in Chinese Han population. In addition, rs2200733 was associated with clinical recurrence of AF after catheter ablation. In Kaplan-Meier survival analysis, the recurrence-free rates for AF with TT and with TC+CC were 35.5% and 61.9%, respectively (P=0.0009). In multivariate Cox regression analysis, rs2200733 was strong independent risk factor for recurrence. CONCLUSION: rs2200733 risk allele at the 4q25 predicted impaired clinical response to catheter ablation for AF in Chinese Han population. Our findings suggested rs2200733 polymorphism may be used as a clinical tool for selection of patients for AF catheter ablation.


Assuntos
Grupo com Ancestrais do Continente Asiático , Fibrilação Atrial/etiologia , Fibrilação Atrial/cirurgia , Ablação por Cateter , Idoso , Fibrilação Atrial/etnologia , Estudos de Casos e Controles , China , Feminino , Predisposição Genética para Doença/etnologia , Genótipo , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Recidiva , Análise de Sobrevida
15.
J Nucl Med ; 57(12): 1893-1898, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27445295

RESUMO

Myocardial perfusion imaging (MPI) with SPECT is a well-established tool for the diagnosis of coronary artery disease (CAD). However, soft-tissue attenuation is a common artifact that limits the diagnostic accuracy of MPI. The aim of this study was to determine whether attenuation correction (AC) improved the diagnostic performance of MPI, using coronary angiography as a reference standard. METHODS: MEDLINE and EMBASE were searched until March 2015 for studies evaluating AC MPI for the diagnosis of CAD. Methodologic quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. For each study, the sensitivity, specificity, and diagnostic odds ratio, along with 95% confidence intervals (CIs), were calculated to determine the diagnostic accuracy of AC versus non-attenuation-corrected (NAC) MPI. A bivariate mixed-effects model was applied for pooling the data. RESULTS: Of 201 articles, 17 studies (1,701 patients) were identified, including 5 studies that used CT AC, 12 studies that used radionuclide source AC (RAC), and 15 studies that reported NAC results. The pooled sensitivities across studies were 0.80 (95% CI, 0.64-0.91), 0.85 (95% CI, 0.81-0.88), 0.84 (95% CI, 0.79-0.88), and 0.80 (95% CI, 0.75-0.85) for CT AC, RAC, all AC, and NAC, respectively. The pooled specificities were 0.83 (95% CI, 0.71-0.91), 0.81 (95% CI, 0.73-0.86), 0.80 (95% CI, 0.74-0.85), and 0.68 (95% CI, 0.61-0.74). Both sensitivities and specificities resulted in a pooled diagnostic odds ratio of 20 (95% CI, 12-34), 24 (95% CI, 13-43), 22 (95% CI, 13-35), and 9 (7-11). Significant differences in specificity and diagnostic odds ratios were noted when AC (including CT AC, RAC, and all AC) was compared with NAC. CONCLUSION: The results from this study suggested that AC should be applied to MPI to improve the diagnosis of CAD, especially the specificity.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/métodos , Humanos , Processamento de Imagem Assistida por Computador , Sensibilidade e Especificidade
16.
Stud Health Technol Inform ; 220: 142-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27046567

RESUMO

This study investigated how the ergonomic factors, such as hand dominance and postural selection, influenced on surgical performance regarding the changes of muscle activity. Twenty novices performed two virtual laparoscopic surgical training tasks and five target muscle activities were measured. Compared with using dominant hand, surgical skills performance using non-dominant hand increased muscle activities. Muscle fatigue is more likely induced in standing position than sitting position during practice. This study suggests an emerging need to focus on hand dominance during laparoscopic surgical training to address the impact of hand discrepancy on bimanual coordination. It is also important to pay attention on postural selection during training to reduce muscle fatigue, which possibly leads to injuries.


Assuntos
Instrução por Computador/métodos , Lateralidade Funcional/fisiologia , Laparoscopia Assistida com a Mão/educação , Mãos/fisiologia , Músculo Esquelético/fisiologia , Equilíbrio Postural , Adulto , Feminino , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Stud Health Technol Inform ; 220: 450-3, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27046621

RESUMO

This study examined how hand dominance could influence postural sway during laparoscopic skills practice. Ten inexperienced medical trainees performed a peg transfer task using the Fundamentals of Laparoscopic Surgery (FLS) training box and the virtual reality (VR) trainer. Surface electromyographic recordings of upper and lower limb muscles were taken, while the postural sway was measured by a pressure mapping system. Skills performance using the non-dominant hand required more muscle effort and increased more postural sway. Compared with the FLS training box, training with VR decreased the use of muscle effort and could reduce the influence of hand dominance on the overall postural sway during laparoscopic surgical skills practice.


Assuntos
Competência Clínica , Lateralidade Funcional/fisiologia , Mãos/fisiologia , Laparoscopia/métodos , Equilíbrio Postural/fisiologia , Cirurgia Assistida por Computador/métodos , Adulto , Instrução por Computador/métodos , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Interface Usuário-Computador
18.
BMC Plant Biol ; 16: 84, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27071313

RESUMO

BACKGROUND: The exon junction complex (EJC), which contains four core components, eukaryotic initiation factor 4AIII (eIF4AIII), MAGO/NASHI (MAGO), Y14/Tsunagi/RNA-binding protein 8A, and Barentsz/Metastatic lymph node 51, is formed in both nucleus and cytoplasm, and plays important roles in gene expression. Genes encoding core EJC components have been found in plants, including rice. Currently, the functional characterizations of MAGO and Y14 homologs have been demonstrated in rice. However, it is still unknown whether eIF4AIII is essential for the functional EJC in rice. RESULTS: This study investigated two DEAD box RNA helicases, OsRH2 and OsRH34, which are homologous to eIF4AIII, in rice. Amino acid sequence analysis indicated that OsRH2 and OsRH34 had 99 % identity and 100 % similarity, and their gene expression patterns were similar in various rice tissues, but the level of OsRH2 mRNA was about 58-fold higher than that of OsRH34 mRNA in seedlings. From bimolecular fluorescence complementation results, OsRH2 and OsRH34 interacted physically with OsMAGO1 and OsY14b, respectively, which indicated that both of OsRH2 and OsRH34 were core components of the EJC in rice. To study the biological roles of OsRH2 and OsRH34 in rice, transgenic rice plants were generated by RNA interference. The phenotypes of three independent OsRH2 and OsRH34 double-knockdown transgenic lines included dwarfism, a short internode distance, reproductive delay, defective embryonic development, and a low seed setting rate. These phenotypes resembled those of mutants with gibberellin-related developmental defects. In addition, the OsRH2 and OsRH34 double-knockdown transgenic lines exhibited the accumulation of unspliced rice UNDEVELOPED TAPETUM 1 mRNA. CONCLUSIONS: Rice contains two eIF4AIII paralogous genes, OsRH2 and OsRH34. The abundance of OsRH2 mRNA was about 58-fold higher than that of OsRH34 mRNA in seedlings, suggesting that the OsRH2 is major eIF4AIII in rice. Both OsRH2 and OsRH34 are core components of the EJC, and participate in regulating of plant height, pollen, and seed development in rice.


Assuntos
RNA Helicases DEAD-box/genética , Fator de Iniciação 4A em Eucariotos/genética , Éxons/genética , Oryza/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Núcleo Celular/metabolismo , Citoplasma/metabolismo , RNA Helicases DEAD-box/metabolismo , Fator de Iniciação 4A em Eucariotos/classificação , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Isoenzimas/genética , Isoenzimas/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia de Fluorescência , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Filogenia , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Pólen/genética , Pólen/crescimento & desenvolvimento , Pólen/metabolismo , Ligação Proteica , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Homologia de Sequência de Aminoácidos
19.
Acta Pharmacol Sin ; 37(4): 473-82, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26972492

RESUMO

AIM: Sildenafil, a phosphodiesterase 5 (PDE5) inhibitor, has been shown to exert beneficial effects in heart failure. The purpose of this study was to test whether sildenafil suppressed transverse-tubule (T-tubule) remodeling in left ventricular (LV) failure and thereby providing the therapeutic benefits. METHODS: A pressure overload-induced murine heart failure model was established in mice by thoracic aortic banding (TAB). One day after TAB, the mice received sildenafil (100 mg·kg(-1)·d(-1), sc) or saline for 5 weeks. At the end of treatment, echocardiography was used to examine LV function. Then the intact hearts were dissected out and placed in Langendorff-perfusion chamber for in situ confocal imaging of T-tubule ultrastructure from epicardial myocytes. RESULTS: TAB surgery resulted in heart failure accompanied by remarkable T-tubule remodeling. Sildenafil treatment significantly attenuated TAB-induced cardiac hypertrophy and congestive heart failure, improved LV contractile function, and preserved T-tubule integrity in LV cardiomyocytes. But sildenafil treatment did not significantly affect the chamber dilation. The integrity of LV T-tubule structure was correlated with cardiac hypertrophy (R(2)=0.74, P<0.01) and global LV function (R(2)=0.47, P<0.01). CONCLUSION: Sildenafil effectively ameliorates LV T-tubule remodeling in TAB mice, revealing a novel mechanism underlying the therapeutic benefits of sildenafil in heart failure.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Inibidores da Fosfodiesterase 5/uso terapêutico , Citrato de Sildenafila/uso terapêutico , Remodelação Ventricular/efeitos dos fármacos , Animais , Cardiomegalia/tratamento farmacológico , Cardiomegalia/patologia , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Função Ventricular Esquerda/efeitos dos fármacos
20.
Sci Rep ; 6: 19972, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26804487

RESUMO

Performance of interferon-gamma release assays (IGRAs) is influenced by preanalytical, laboratory and host factors. The data regarding how critical illnesses influence IGRA results are limited. This study aimed to investigate IGRA performance among critically ill patients. Patients admitted to intensive care unit (ICU) were prospectively enrolled, and underwent QuantiFERON-TB Gold In-Tube testing on admission and discharge. The associations between patient factors and IGRA results were explored. In total, 118 patients were included. IGRA results on admission were positive, negative and indeterminate for 10 (9%), 36 (31%) and 72 (61%) patients. All indeterminate results were due to a low mitogen response. Indeterminate results were associated with higher disease severity and lower serum albumin levels. Ninety (76%) patients survived to ICU discharge and had repeat IGRA testing 13.3 ± 10.1 days after first ones. Of those, 43 (48%) had indeterminate results, and no IGRA conversion or reversion was observed. The majority (35/51, 69%) of ICU survivors with initial indeterminate results still had indeterminates on follow-up testing. Acute critical illnesses exert a significant impact on IGRA performance and a high proportion of indeterminate results was seen in ICU patients. This study highlights limitation of IGRAs in the critically ill and judicious selection of patients to be tested should be considered.


Assuntos
Estado Terminal/terapia , Testes de Liberação de Interferon-gama , Interferon gama/metabolismo , Tuberculose Latente/terapia , Idoso , Feminino , Humanos , Unidades de Terapia Intensiva , Tuberculose Latente/microbiologia , Tuberculose Latente/patologia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/patogenicidade
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