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1.
Artigo em Inglês | MEDLINE | ID: mdl-38711168

RESUMO

BACKGROUND AND AIM: Transarterial chemoembolization (TACE) is one of the standard modalities used to treat unresectable hepatocellular carcinoma (HCC), but the effectiveness of TACE for treating patients with a solitary small (≤3 cm) HCC and well-preserved liver function has not been definitively established. This study aimed to determine the therapeutic impact of TACE in patients with these characteristics. METHODS: This multicenter (four university hospitals) retrospective cohort study analyzed the medical records of 250 patients with a solitary small (≤3 cm) HCC and Child-Turcotte-Pugh (CTP) class A liver function diagnosed over 10 years. Posttreatment outcomes, including overall survival (OS), recurrence-free survival (RFS), and adverse events, were assessed following TACE therapy. RESULTS: One hundred and thirty-eight of the 250 patients (55.2%) treated with TACE achieved complete remission (CR). Overall median OS was 77.7 months, and median OS was significantly longer in the CR group than in the non-CR group (89.1 vs. 58.8 months, P = 0.001). Median RFS was 19.1 months in the CR group. Subgroup analysis identified hypertension, an elevated serum albumin level, and achieving CR as significant positive predictors of OS, whereas diabetes, hepatitis c virus infection, and tumor size (>2 cm) were poor prognostic factors of OS. CONCLUSIONS: The study demonstrates the effectiveness of TACE as a viable alternative for treating solitary small (≤3 cm) HCC in CTP class A patients.

2.
BMC Biol ; 20(1): 247, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36345010

RESUMO

BACKGROUND: Sequential effects of environmental stimuli are ubiquitous in most behavioral tasks involving magnitude estimation, memory, decision making, and emotion. The human visual system exploits continuity in the visual environment, which induces two contrasting perceptual phenomena shaping visual perception. Previous work reported that perceptual estimation of a stimulus may be influenced either by attractive serial dependencies or repulsive aftereffects, with a number of experimental variables suggested as factors determining the direction and magnitude of sequential effects. Recent studies have theorized that these two effects concurrently arise in perceptual processing, but empirical evidence that directly supports this hypothesis is lacking, and it remains unclear whether and how attractive and repulsive sequential effects interact in a trial. Here we show that the two effects concurrently modulate estimation behavior in a typical sequence of perceptual tasks. RESULTS: We first demonstrate that observers' estimation error as a function of both the previous stimulus and response cannot be fully described by either attractive or repulsive bias but is instead well captured by a summation of repulsion from the previous stimulus and attraction toward the previous response. We then reveal that the repulsive bias is centered on the observer's sensory encoding of the previous stimulus, which is again repelled away from its own preceding trial, whereas the attractive bias is centered precisely on the previous response, which is the observer's best prediction about the incoming stimuli. CONCLUSIONS: Our findings provide strong evidence that sensory encoding is shaped by dynamic tuning of the system to the past stimuli, inducing repulsive aftereffects, and followed by inference incorporating the prediction from the past estimation, leading to attractive serial dependence.


Assuntos
Tomada de Decisões , Percepção Visual , Humanos , Tomada de Decisões/fisiologia , Percepção Visual/fisiologia , Visão Ocular
3.
J Vis ; 23(11): 77, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37733501

RESUMO

Perceptual decisions involve a process that evolves over time until it reaches a decision boundary. It's important to understand how this process unfolds. Recent psychophysical data indicates that the visual system extracts motion axis information faster than motion direction information (Kwon et al., 2015, J Vision). To understand the underlying mechanisms, we developed a biophysically realistic cortical network model of decision making. We generalized the two-variable reduced spiking neural network (Wong et al., 2006, J Neuroscience) to four-variable. The network input is based on motion energy (Adelson et al., 1985, Josa a) and the temporal profile of surround influence (Tadin et al., 2006, J Neuroscience). The model reproduces the prior experimental findings, showing the motion axis extraction before direction extraction. It reveals a stronger axis-wise inhibitory connection between the selective neural populations than the direction-wise inhibitory connection. We further designed a recurrent deep neural network to validate the neural population connectivity pattern. Our model provides a quantitative explanation for the temporal evolution of motion direction judgments. The results show that the spatiotemporal filtering for visual motion integration, the center-surround antagonism, and stronger axis-wise inhibitory connection between the selective neural populations can explain how the visual system can extract motion axis orientation before detecting motion direction.


Assuntos
Julgamento , Redes Neurais de Computação , Humanos , Movimento (Física)
4.
Int J Mol Sci ; 24(2)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36675278

RESUMO

Epithelial-mesenchymal transition (EMT) has been implicated in cancer progression, invasion, and metastasis. We aimed to evaluate the correlations between clinicopathological characteristics and EMT markers in patients with hepatocellular carcinoma (HCC) who underwent surgical resection and to identify the key regulator in EMT process. Fresh-frozen HCC tissues and adjacent nontumor liver tissues from 30 patients who underwent surgical resection were provided by the Gachon University Gil Medical Center Bio Bank. Human HCC cell lines, Hep3B, SNU449, and Huh7 cells were transfected with Rac1 siRNA and exposed to hypoxic conditions. The combined EMT markers expression (down-expression of E-cadherin and overexpression of p21-activated kinases 1 (PAK1)/Snail) by Western blot in HCC tissues when compared to adjacent nontumor liver tissues was significantly associated with macrovascular invasion (p = 0.021), microvascular invasion (p = 0.001), large tumor size (p = 0.021), and advanced tumor stage (p = 0.015). Patients with combined EMT markers expression showed early recurrence and poor overall survival. In vitro studies showed that Rac1 knockdown decreased the expression of EMT markers including PAK1 and Snail in hypoxia-induced Hep3B cells and suppressed the migration and invasion of hypoxia-induced HCC cells. Rac1 may be a potential therapeutic target for inhibition of EMT process through the inhibition of PAK1 and Snail in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Transição Epitelial-Mesenquimal/genética , Relevância Clínica , Transdução de Sinais , Hipóxia/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo
5.
PLoS Comput Biol ; 17(12): e1009633, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34914689

RESUMO

Many decisions in life are sequential and constrained by a time window. Although mathematically derived optimal solutions exist, it has been reported that humans often deviate from making optimal choices. Here, we used a secretary problem, a classic example of finite sequential decision-making, and investigated the mechanisms underlying individuals' suboptimal choices. Across three independent experiments, we found that a dynamic programming model comprising subjective value function explains individuals' deviations from optimality and predicts the choice behaviors under fewer and more opportunities. We further identified that pupil dilation reflected the levels of decision difficulty and subsequent choices to accept or reject the stimulus at each opportunity. The value sensitivity, a model-based estimate that characterizes each individual's subjective valuation, correlated with the extent to which individuals' physiological responses tracked stimuli information. Our results provide model-based and physiological evidence for subjective valuation in finite sequential decision-making, rediscovering human suboptimality in subjectively optimal decision-making processes.


Assuntos
Tomada de Decisões/fisiologia , Pupila/fisiologia , Adulto , Tecnologia de Rastreamento Ocular , Feminino , Humanos , Masculino , Modelos Psicológicos , Psicofísica , Adulto Jovem
6.
Graefes Arch Clin Exp Ophthalmol ; 260(5): 1551-1563, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35006331

RESUMO

PURPOSE: Current evidence demonstrates the effectiveness of vision training for presbyopia. We developed and examined a training program to test the effectiveness of alternating focal distances as a training method. METHODS: We devised a sharpness discrimination task, in which participants judged whether the stimulus was a sine- or square-wave grating, and tested in two training groups and one control group. In the alternating-distance training group (N = 8, age 49-64), participants had to alternate the fixation between a near- and far-screen. In the fixed-distance training group (N=8, age 47-65), participants fixated on the same-distance target for the whole block. Before and after the 20 training sessions, we measured the near- and far-visual acuity (VA) using the Landolt C and Early Treatment Diabetic Retinopathy Study (ETDRS) tasks and contrast sensitivity using the qCSF procedure. The control group (N=8, age 49-65) participated only in the pre- and post-tests. RESULTS: Both training groups showed a significant improvement between the pre- and post-tests in the Landolt C task, and the improvement sizes were not significantly different between the groups. In the ETDRS task, only the fixed-distance training group showed significant improvement, although there was no significant difference between the two groups. Neither group showed improvement in the contrast sensitivity task compared to the control group. CONCLUSION: The novel sharpness discrimination task can be an effective training method for presbyopia to prevent the deterioration of VA; however, contrary to popular belief, the effect of alternating-distance training was comparable to or even weaker than that of fixed-distance training.


Assuntos
Presbiopia , Baixa Visão , Idoso , Sensibilidades de Contraste , Humanos , Pessoa de Meia-Idade , Presbiopia/terapia , Visão Ocular , Acuidade Visual
7.
J Korean Med Sci ; 37(11): e92, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35315603

RESUMO

BACKGROUND: Tenofovir disoproxil fumarate (TDF, Viread®) had been used as a standard treatment option of chronic hepatitis B (CHB). This clinical trial was conducted to evaluate the efficacy and safety of DA-2802 (tenofovir disoproxil orotate) compared to TDF. METHODS: The present study was a double blind randomized controlled trial. Patients with CHB were recruited from 25 hospitals in Korea and given DA-2802 at a dose of 319 mg once daily or Viread® at a dose of 300 mg once daily for 48 weeks from March 2017 to January 2019. Change in hepatitis B virus (HBV) DNA level at week 48 after dosing compared to baseline was the primary efficacy endpoint. Secondary efficacy endpoints were proportions of subjects with undetectable HBV DNA, those with normal alanine aminotransferase (ALT) levels, and those with loss of hepatitis B envelop antigen (HBeAg), those with loss of hepatitis B surface antigen (HBsAg). Adverse events (AEs) were also investigated. RESULTS: A total of 122 patients (DA-2802 group: n = 61, Viread® group: n = 61) were used as full analysis set for efficacy analysis. Mean age, proportion of males, laboratory results and virologic characteristics were not different between the two groups. The change in HBV DNA level at week 48 from baseline was -5.13 ± 1.40 in the DA-2802 group and -4.97 ± 1.40 log10 copies/mL in the Viread® group. The analysis of primary endpoint using the nonparametric analysis of covariance showed statistically significant results (P < 0.001), which confirmed non-inferiority of DA-2802 to Viread® by a prespecified noninferiority margin of 1. The proportion of undetectable HBV DNA was 78.7% in the DA-2802 group and 75.4% in the Viread® group (P = 0.698). The proportion of subjects who had normal ALT levels was 75.4% in the DA-2802 group and 73.3% in the Viread® group (P = 0.795). The proportion of those with HBeAg loss was 8.1% in the DA-2802 group and 10.8% in the Viread® group (P = 1.000). No subject showed HBsAg loss. The frequency of AEs during treatment was similar between the two groups. Most AEs were mild to moderate in severity. CONCLUSION: DA-2802 is considered an effective and safe treatment for patients with CHB. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02967939.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Ácido Orótico/uso terapêutico , Tenofovir/uso terapêutico , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia , Resultado do Tratamento
8.
Int J Mol Sci ; 22(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502229

RESUMO

The two-pore domain K+ (K2P) channel, which is involved in setting the resting membrane potential in neurons, is an essential target for receptor agonists. Activation of the γ-aminobutyric acid (GABA) receptors (GABAAR and GABABR) reduces cellular excitability through Cl- influx and K+ efflux in neurons. Relatively little is known about the link between GABAAR and the K+ channel. The present study was performed to identify the effect of GABAR agonists on K2P channel expression and activity in the neuroblastic B35 cells that maintain glutamic acid decarboxylase (GAD) activity and express GABA. TASK and TREK/TRAAK mRNA were expressed in B35 cells with a high level of TREK-2 and TRAAK. In addition, TREK/TRAAK proteins were detected in the GABAergic neurons obtained from GABA transgenic mice. Furthermore, TREK-2 mRNA and protein expression levels were markedly upregulated in B35 cells by GABAAR and GABABR agonists. In particular, muscimol, a GABAAR agonist, significantly increased TREK-2 expression and activity, but the effect was reduced in the presence of the GABAAR antagonist bicuculine or TREK-2 inhibitor norfluoxetine. In the whole-cell and single-channel patch configurations, muscimol increased TREK-2 activity, but the muscimol effect disappeared in the N-terminal deletion mutant. These results indicate that muscimol directly induces TREK-2 activation through the N-terminus and suggest that muscimol can reduce cellular excitability by activating the TREK-2 channel and by inducing Cl- influx in GABAergic neurons.


Assuntos
Agonistas de Receptores de GABA-A/farmacologia , Neurônios GABAérgicos/metabolismo , Potenciais da Membrana , Muscimol/farmacologia , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Receptores de GABA/química , Animais , Células Cultivadas , Neurônios GABAérgicos/efeitos dos fármacos , Células HEK293 , Humanos , Masculino , Camundongos , Canais de Potássio de Domínios Poros em Tandem/genética , Ratos
9.
J Gastroenterol Hepatol ; 35(6): 1078-1087, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31907970

RESUMO

BACKGROUND AND AIM: Exogenous 8-hydroxydeoxyguanosine (8-OHdG) was suggested as an inhibitor of Rac1 and NADPH oxidase (NOX). The aim of this study was to evaluate the effects of the exogenous 8-OHdG on hepatic fibrogenesis in vitro and in vivo model of liver fibrosis. METHODS: Adult Sprague-Dawley rats were allocated to sham-operated rats (n = 7), rats that underwent bile duct ligation (BDL) (n = 6), and BDL rats treated with 8-OHdG (60 mg/kg/day by gavage, n = 6). All rats were sacrificed on day 21. Double immunofluorescence staining between either NOX1 or NOX2 and α-smooth muscle actin (SMA) in liver was performed. Hepatic fibrotic contents were assessed by hydroxyproline assay and quantified by Sirius red staining. In vitro, hepatic stellate cell (HSC) line LX-2 and HHSteC cells were stimulated by angiotensin II (10 µM). The reactive oxygen species (ROS) production was measured by confocal microscopy. The expressions of NOX1, NOX2, α-SMA, transforming growth factor (TGF)-ß1, and collagen Iα were analyzed by quantitative real-time polymerase chain reaction or immunoblotting. RESULTS: The 8-OHdG treatment in BDL rats reduced the NOX1 and NOX2 protein expression, which overlapped with α-SMA compared with BDL rats. The 8-OHdG treatment in BDL rats significantly decreased the mRNA expression of NOX1, NOX2, α-SMA, TGF-ß1, and collagen Iα, and fibrotic contents. Increases of ROS production, Rac1 activation, NOX1, NOX2, and fibronectin expression induced by angiotensin II in HSCs were attenuated by 8-OHdG. CONCLUSIONS: Rac1 activation and NOX-derived ROS are implicated to liver fibrosis. The 8-OHdG ameliorates liver fibrosis through the inhibition of Rac1 activation and NOX-derived ROS.


Assuntos
8-Hidroxi-2'-Desoxiguanosina/farmacologia , 8-Hidroxi-2'-Desoxiguanosina/uso terapêutico , Actinas/genética , Actinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , NADPH Oxidase 1/metabolismo , NADPH Oxidase 2/genética , NADPH Oxidase 2/metabolismo , NADPH Oxidases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteínas rac1 de Ligação ao GTP/metabolismo , Animais , Linhagem Celular , Colágeno/genética , Colágeno/metabolismo , Modelos Animais de Doenças , Células Estreladas do Fígado , Cirrose Hepática/etiologia , Cirrose Hepática/metabolismo , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
10.
J Hand Surg Am ; 45(5): e1-e10, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31005462

RESUMO

PURPOSE: The aims of this study were to verify proximal phalangeal head normalization after a stretching exercise in patients with infantile-type camptodactyly and to propose radiographic indices for quantifying bony deformities. METHODS: Forty-eight fingers of 20 patients with camptodactyly were enrolled in this study. All patients and their parents received instruction on how to perform the stretching exercise. The qualitative assessments of proximal phalangeal head remodeling were conducted by consensus of 2 hand surgeons. Two radiographic parameters, head triangle ratio (HTR) and head angle (HA), were measured on finger lateral radiographs taken at the initial visit and at 12-month follow-up. The intra- and interobserver reliability of both parameters was assessed. Those parameters of the patients were compared with those of 177 fingers of 80 children without camptodactyly. The extent of proximal interphalangeal (PIP) joint flexion contracture was used to evaluate clinical outcomes resulting from nonsurgical treatment. RESULTS: Qualitative assessments of proximal phalangeal head remodeling exhibited meaningful improvements. Both radiographic parameters showed significant change between their status before and after intervention and had excellent intra- and interobserver reliability. Average PIP joint flexion contracture significantly improved. In the noncamptodactyly group, neither parameter showed significant differences in accordance with finger types and age ranges. CONCLUSIONS: Stretching improved movement within the proximal phalangeal joint and helped to restore proximal phalangeal head roundness and concentricity in patients with infantile-type camptodactyly. The HTR and HA would be useful indices for objectively assessing the degree of bony deformity in patients with camptodactyly. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Assuntos
Contratura , Falanges dos Dedos da Mão , Luxações Articulares , Criança , Contratura/diagnóstico por imagem , Contratura/terapia , Articulações dos Dedos/diagnóstico por imagem , Humanos , Amplitude de Movimento Articular , Reprodutibilidade dos Testes
11.
J Hepatol ; 70(4): 684-691, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30529387

RESUMO

BACKGROUND & AIMS: Sorafenib is first-line standard of care for patients with advanced hepatocellular carcinoma (HCC), yet it confers limited survival benefit. Therefore, we aimed to compare clinical outcomes of sorafenib combined with concurrent conventional transarterial chemoembolization (cTACE) vs. sorafenib alone in patients with advanced HCC. METHODS: In this investigator-initiated, multicenter, phase III trial, patients were randomized to receive sorafenib alone (Arm S, n = 169) or in combination with cTACE on demand (Arm C, n = 170). Sorafenib was started within 3 days and cTACE within 7-21 days of randomization. The primary endpoint was overall survival (OS). RESULTS: For Arms C and S, the median OS was 12.8 vs. 10.8 months (hazard ratio [HR] 0.91; 90% CI 0.69-1.21; p = 0.290); median time to progression, 5.3 vs. 3.5 months (HR 0.67; 90% CI 0.53-0.85; p = 0.003); median progression-free survival, 5.2 vs. 3.6 months (HR 0.73; 90% CI 0.59-0.91; p = 0.01); and tumor response rate, 60.6% vs. 47.3% (p = 0.005). For Arms C and S, serious (grade ≥3) adverse events occurred in 33.3% vs. 19.8% (p = 0.006) of patients and included increased alanine aminotransferase levels (20.3% vs. 3.6%), hyperbilirubinemia (11.8% vs. 3.0%), ascites (11.8% vs. 4.2%), thrombocytopenia (7.2% vs. 1.2%), anorexia (7.2% vs. 1.2%), and hand-foot skin reaction (10.5% vs. 11.4%). A post hoc subgroup analysis compared OS in Arm C patients (46.4%) receiving ≥2 cTACE sessions to Arm S patients (18.6 vs. 10.8 months; HR 0.58; 95% CI 0.40-0.82; p = 0.006). CONCLUSION: Compared with sorafenib alone, sorafenib combined with cTACE did not improve OS in patients with advanced HCC. However, sorafenib combined with cTACE significantly improved time to progression, progression-free survival, and tumor response rate. Sorafenib alone remains the first-line standard of care for patients with advanced HCC. LAY SUMMARY: For patients with advanced hepatocellular carcinoma requiring sorafenib therapy, co-administration with conventional transarterial chemoembolization did not improve overall survival compared to sorafenib alone. Therefore, sorafenib alone remains the first-line standard of care for patients with advanced hepatocellular carcinoma. Clinical Trial Number: NCT01829035.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/tratamento farmacológico , Sorafenibe/uso terapêutico , Idoso , Alanina Transaminase/sangue , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Ascite/etiologia , Quimioembolização Terapêutica/efeitos adversos , Terapia Combinada , Feminino , Seguimentos , Humanos , Hiperbilirrubinemia/etiologia , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Sorafenibe/administração & dosagem , Sorafenibe/efeitos adversos , Trombocitopenia/etiologia
12.
J Korean Med Sci ; 34(41): e264, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31650719

RESUMO

BACKGROUND: The long-term data with direct acting antiviral agents were rare. This study investigated the durability of a sustained virologic response (SVR) and the improvement of fibrosis after daclatasvir and asunaprevir (DCV/ASV) treatment in genotype 1b (GT1b) hepatitis C virus (HCV)-infected patients. METHODS: A total of 288 HCV GT1b patients without baseline non-structural 5A (NS5A) resistance-associated substitution (RAS) treated with DCV/ASV were enrolled. Virologic response was measured at 12 weeks and 1 year after treatment completion. In cirrhotic patients, liver function, aspartate transaminase to platelet ratio index (APRI), FIB-4 index, fibrosis index (FI), and liver stiffness measurement (LSM) at baseline and 1 year after treatment completion were evaluated. RESULTS: SVR12 was obtained in 278 patients (96.5%). Six patients who checked NS5A RAS after treatment failure were RAS positive. Only one patient showed no durability of SVR. In cirrhotic patients who achieved SVR12 (n = 59), the changes of albumin (3.8 [2.2-4.7] to 4.3 [2.4-4.9] g/dL; P < 0.001), platelet count (99 [40-329] to 118 [40-399] × 10³/mm³; P < 0.001), APRI (1.8 [0.1-14.8] to 0.6 [0.1-4.8]; P < 0.001), FIB-4 index (5.45 [0.6-32.8] to 3.3 [0.4-12.2]; P < 0.001), FI (5.5 [0.6-32.8] to 3.3 [0.4-12.2]; P < 0.001), and LSM (17.2 [5.3-48.0] to 11.2 [3.7-28.1] kPa; P = 0.001) between baseline and 1 year after treatment completion were observed. CONCLUSION: DCV/ASV treatment for HCV GT1b infected patients without RAS achieved high SVR rates and showed durable SVR. Cirrhotic patients who achieved SVR12 showed the improvement of liver function and fibrosis markers.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Imidazóis/uso terapêutico , Isoquinolinas/uso terapêutico , Sulfonamidas/uso terapêutico , Resposta Viral Sustentada , Adulto , Aspartato Aminotransferases/sangue , Carbamatos , Farmacorresistência Viral , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Humanos , Fígado/fisiologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Pirrolidinas , RNA Viral/sangue , Resultado do Tratamento , Valina/análogos & derivados
13.
Proc Natl Acad Sci U S A ; 112(26): 8142-7, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26080410

RESUMO

Despite growing evidence for perceptual interactions between motion and position, no unifying framework exists to account for these two key features of our visual experience. We show that percepts of both object position and motion derive from a common object-tracking system--a system that optimally integrates sensory signals with a realistic model of motion dynamics, effectively inferring their generative causes. The object-tracking model provides an excellent fit to both position and motion judgments in simple stimuli. With no changes in model parameters, the same model also accounts for subjects' novel illusory percepts in more complex moving stimuli. The resulting framework is characterized by a strong bidirectional coupling between position and motion estimates and provides a rational, unifying account of a number of motion and position phenomena that are currently thought to arise from independent mechanisms. This includes motion-induced shifts in perceived position, perceptual slow-speed biases, slowing of motions shown in visual periphery, and the well-known curveball illusion. These results reveal that motion perception cannot be isolated from position signals. Even in the simplest displays with no changes in object position, our perception is driven by the output of an object-tracking system that rationally infers different generative causes of motion signals. Taken together, we show that object tracking plays a fundamental role in perception of visual motion and position.


Assuntos
Percepção de Movimento , Percepção Visual , Humanos , Modelos Biológicos
15.
Dig Dis Sci ; 62(3): 808-816, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28035553

RESUMO

BACKGROUND: Sustained abnormal serum alanine aminotransferase (ALT) levels can increase the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B. AIM: This study is aimed to confirm the impact of rapid ALT normalization (≤30 IU/L) on HCC risk in patients with hepatitis B virus (HBV)-associated cirrhosis after entecavir (ETV) commencement. METHODS: A total of 578 treatment-naïve patients with HBV-associated cirrhosis (mean age 51 ± 9 years, male sex 63.3%) were treated with ETV for more than 1 year. Serum ALT and HBV DNA levels were measured at three time points (baseline, 6, and 12 months after ETV commencement) and subjected to risk factor analysis. RESULTS: Median follow-up after ETV commencement was 43 (12-98) months. Cumulative incidences of HCC at 1, 3, 5, and 7 years were 0.3, 8.5, 19.5, and 30.6%, respectively. Univariate Cox regression analysis showed that older age, abnormal ALT at 6 months or 12 months, and lower platelet count were significant risk factors for HCC. However, gender, HBeAg positivity, abnormal ALT levels or HBV DNA levels at baseline, and detectable HBV DNA at 6 or 12 months were not risk factors. Multivariate analysis showed that older age (P < 0.001), abnormal ALT at 12 months (P = 0.006), and lower platelet count (P = 0.034) were the risk factors for HCC. CONCLUSIONS: Abnormal serum ALT levels after ETV commencement are significant risk factor for HCC. Therefore, ALT should be rapidly normalized to minimize the risk of HCC development in patients with HBV-associated cirrhosis.


Assuntos
Alanina Transaminase , Carcinoma Hepatocelular/diagnóstico , Guanina/análogos & derivados , Hepatite B Crônica , Cirrose Hepática/sangue , Neoplasias Hepáticas/diagnóstico , Adulto , Fatores Etários , Alanina Transaminase/análise , Alanina Transaminase/sangue , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Feminino , Guanina/administração & dosagem , Guanina/efeitos adversos , Hepatite B Crônica/complicações , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/epidemiologia , Humanos , Incidência , Cirrose Hepática/etiologia , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas/estatística & dados numéricos , Prognóstico , República da Coreia/epidemiologia , Medição de Risco
16.
Int J Mol Sci ; 19(1)2017 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-29295567

RESUMO

The topical application of minoxidil may achieve millimolar concentrations in the skin. We investigated whether millimolar minoxidil could induce vascular endothelial growth factor (VEGF), a possible effector for minoxidil-mediated hair growth, and how it occurred at the molecular level. Cell-based experiments were performed to investigate a molecular mechanism underlying the millimolar minoxidil induction of VEGF. The inhibitory effect of minoxidil on hypoxia-inducible factor (HIF) prolyl hydroxylase-2 (PHD-2) was tested by an in vitro von Hippel-Lindau protein (VHL) binding assay. To examine the angiogenic potential of millimolar minoxidil, a chorioallantoic membrane (CAM) assay was used. In human keratinocytes and dermal papilla cells, millimolar minoxidil increased the secretion of VEGF, which was not attenuated by a specific adenosine receptor antagonist that inhibits the micromolar minoxidil induction of VEGF. Millimolar minoxidil induced hypoxia-inducible factor-1α (HIF-1α), and the induction of VEGF was dependent on HIF-1. Moreover, minoxidil applied to the dorsal area of mice increased HIF-1α and VEGF in the skin. In an in vitro VHL binding assay, minoxidil directly inhibited PHD-2, thus preventing the hydroxylation of cellular HIF-1α and VHL-dependent proteasome degradation and resulting in the stabilization of HIF-1α protein. Minoxidil inhibition of PHD-2 was reversed by ascorbate, a cofactor of PHD-2, and the minoxidil induction of cellular HIF-1α was abrogated by the cofactor. Millimolar minoxidil promoted angiogenesis in the CAM assay, an in vivo angiogenic test, and this was nullified by the specific inhibition of VEGF. Our data demonstrate that PHD may be the molecular target for millimolar minoxidil-mediated VEGF induction via HIF-1.


Assuntos
Prolina Dioxigenases do Fator Induzível por Hipóxia/antagonistas & inibidores , Minoxidil/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ácido Ascórbico/farmacologia , Membrana Corioalantoide/efeitos dos fármacos , Membrana Corioalantoide/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Pele/citologia
17.
J Surg Oncol ; 114(1): 106-11, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27332047

RESUMO

BACKGROUND/AIMS: We analyzed the incidence of change of Barcelona Clinic Liver Cancer (BCLC) stage after add-on Primovist-enhanced magnetic resonance imaging (MRI) in hepatocellular carcinoma (HCC) patients with Barcelona Clinic Liver Cancer stage 0 or A as determined by liver dynamic computed tomography (LDCT). METHODS: A total of 166 patients enrolled prospectively between August 2012 and December 2014 were retrospectively analyzed. The rates of stage change after Primovist-enhanced MRI and the treatment finally adopted in patients with stage change were evaluated. RESULTS: Of the 166 patients, 24 (18.6%) had truly new HCCs. Forty-six (27.7%) and 120 (72.3%) patients had BCLC stages 0 and A, respectively, before Primovist-enhanced MRI, but after Primovist-enhanced MRI, 28 (16.9%), 134 (80.7%), and 4 (2.4%) patients had BCLC stages 0, A, and B, respectively. Tumor stage changed in 22 (13.3%) patients, from 0 to A (18, 39.1%) or A to B (4, 3.3%). CONCLUSIONS: Add-on Primovist-enhanced magnetic resonance imaging can change BCLC stage with 13.3% in patients with BCLC 0 or A staged HCC, as determined by LDCT. J. Surg. Oncol. 2016;114:106-111. © 2016 Wiley Periodicals, Inc.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Meios de Contraste , Gadolínio DTPA , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/cirurgia , Tomada de Decisão Clínica/métodos , Feminino , Seguimentos , Hepatectomia , Humanos , Cuidados Intraoperatórios/métodos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
18.
Proc Natl Acad Sci U S A ; 110(11): E1064-73, 2013 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-23440185

RESUMO

Because of uncertainty and noise, the brain should use accurate internal models of the statistics of objects in scenes to interpret sensory signals. Moreover, the brain should adapt its internal models to the statistics within local stimulus contexts. Consider the problem of hitting a baseball. The impoverished nature of the visual information available makes it imperative that batters use knowledge of the temporal statistics and history of previous pitches to accurately estimate pitch speed. Using a laboratory analog of hitting a baseball, we tested the hypothesis that the brain uses adaptive internal models of the statistics of object speeds to plan hand movements to intercept moving objects. We fit Bayesian observer models to subjects' performance to estimate the statistical environments in which subjects' performance would be ideal and compared the estimated statistics with the true statistics of stimuli in an experiment. A first experiment showed that subjects accurately estimated and used the variance of object speeds in a stimulus set to time hitting behavior but also showed serial biases that are suboptimal for stimuli that were uncorrelated over time. A second experiment showed that the strength of the serial biases depended on the temporal correlations within a stimulus set, even when the biases were estimated from uncorrelated stimulus pairs subsampled from the larger set. Taken together, the results show that subjects adapted their internal models of the variance and covariance of object speeds within a stimulus set to plan interceptive movements but retained a bias to positive correlations.


Assuntos
Antecipação Psicológica/fisiologia , Encéfalo/fisiologia , Retroalimentação Sensorial/fisiologia , Modelos Neurológicos , Feminino , Humanos , Masculino
19.
Cerebrovasc Dis ; 40(1-2): 73-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26184826

RESUMO

BACKGROUND: Low 25-hydroxyvitamin D (25(OH)D) concentrations have been shown to predict risk of cardiovascular disease and all-cause mortality. Although the prevalence of 25(OH)D deficiency is high in patients with acute stroke, the prognostic value of 25(OH)D in stroke has not been clearly established. The purpose of this study was to determine whether the baseline serum 25(OH)D level was associated with the functional outcome in patients with acute ischemic stroke. METHODS: From June 2011 to January 2014, consecutive patients with acute ischemic stroke within 7 days of symptom onset were enrolled in this study from a prospectively maintained stroke registry. Serum 25(OH)D level was measured at admission. Clinical and laboratory data including stroke severity using the National Institute of Health Stroke Scale (NIHSS) score were collected during admission, and the functional outcome at 3 months was assessed by modified Rankin scale (mRS). The association between the baseline 25(OH)D level and a good functional outcome (mRS 0-2) at 3 months was analyzed by multiple logistic regression models. RESULTS: A total of 818 patients were enrolled in this study. Mean age was 66.2 (±12.9) years, and 40.5% were female. The mean 25(OH)D level was 47.2 ± 31.7 nmol/l, and the majority of patients met vitamin D deficient status (<50 nmol/l; 68.8%), while an optimal vitamin D level (≥75 nmol/l) was present in only 13.6% of the patients, and 436 (53.3%) patients showed good functional outcome at 3 months. Serum 25(OH)D levels in patients with good outcomes were significantly higher than those with poor outcome (50.2 ± 32.7 vs. 43.9 ± 30.0 nmol/l, p = 0.007). The 3-month functional outcome was significantly associated with month-specific 25(OH)D quartiles in multivariable logistic regression analysis. After adjustment for age and sex, the highest 25(OH)D quartile group had higher tendency for good functional outcome at 3 months (odds ratio (OR) = 1.68, 95% confidence interval (CI) = 1.13-2.51). After fully adjusting for other potential confounders, such as stroke severity and vascular risk factors, the association was further strengthened with an OR (95% CI) of 1.90 (1.14-3.16). Other factors associated with good functional outcome in multivariable analysis were younger age, lower initial NIHSS score and absence of diabetes. CONCLUSIONS: This study suggests that serum 25(OH)D level is an independent predictor of functional outcome in patients with acute ischemic stroke. Further studies are required to determine whether vitamin D supplementation could improve functional outcome in patients with ischemic stroke.


Assuntos
Isquemia Encefálica/complicações , Acidente Vascular Cerebral/complicações , Deficiência de Vitamina D/complicações , Vitamina D/análogos & derivados , Adulto , Fatores Etários , Idoso , Biomarcadores/sangue , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/terapia , Distribuição de Qui-Quadrado , Avaliação da Deficiência , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Prognóstico , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Fatores de Tempo , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico
20.
J Gastroenterol Hepatol ; 30(12): 1775-81, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26095700

RESUMO

BACKGROUND AND AIM: Entecavir (ETV) induces biochemical and histologic improvement of the liver in patients with chronic hepatitis B. This study aimed to confirm that 2 years of ETV treatment improves liver function and non-invasive fibrosis markers in patients with hepatitis B virus (HBV)-associated cirrhosis. METHODS: A total 472 naïve patients with HBV-associated cirrhosis was treated with ETV for at least 2 years, between March 2007 and December 2012. Model for end-stage liver disease and Child-Pugh (CP) score were used to evaluate the improvement of liver function. Aspartate transaminase to platelet ratio index, FIB-4 index, and fibrosis index were used to evaluate the improvement of fibrosis. RESULTS: The final 370 of 472 patients with HBV-associated cirrhosis were enrolled. Mean age was 51 ± 10 years, and 240 patients (64.9%) were men. The distribution of CP class was 71.1% in A, 24.6% in B, and 4.3% in C. Mean end-stage liver disease and CP score changed over the study period from 8.5 ± 4.6 to 6.2 ± 4.2 (P < 0.001) and from 6.2 ± 1.6 to 5.6 ± 0.9 (P < 0.001), respectively. Aspartate transaminase to platelet ratio index, FIB-4 index, and fibrosis index changed from 3.6 ± 4.5 to 1.5 ± 1.5 (P < 0.001), from 7.0 ± 6.2 to 3.9 ± 2.8 (P < 0.001), and from 3.3 ± 0.9 to 2.5 ± 1.1 (P < 0.001), respectively. CONCLUSIONS: After 2 years of treatment, ETV improves liver function and non-invasive fibrosis markers in patients with HBV-associated cirrhosis.


Assuntos
Guanina/análogos & derivados , Hepatite B/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Fígado/patologia , Adulto , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Feminino , Fibrose , Guanina/administração & dosagem , Hepatite B/complicações , Hepatite B/patologia , Hepatite B/fisiopatologia , Humanos , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
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