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1.
Conscious Cogn ; 119: 103670, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38422759

RESUMO

The debate over the independence of attention and consciousness is ongoing. Prior studies have established that invisible spatial cues can direct attention. However, our exploration extends beyond spatial dimensions to temporal information as a potent guide for attention. A intriguing question arises: Can unconscious temporal cues trigger attentional orienting? To investigate, we employed a modified reaction-time task in Experiments 1 and 2, using Gabor stimuli or human facial stimuli as temporal cues rendered invisible through continuous flash suppression. We aimed to uncover temporal expectation effects (TE effects) without conscious awareness. Moreover, Experiments 3 and 4 probed the boundaries of this unconscious processing, assessing whether conscious temporal cues could modulate TE effects. Our results confirm that invisible temporal cues can induce TE effects, and these effects can be overridden by conscious temporal cues. This dissociation between temporal attention and consciousness provide a new perspective on our understanding of their relationship.


Assuntos
Estado de Consciência , Sinais (Psicologia) , Humanos , Motivação , Conscientização , Tempo de Reação
2.
Environ Monit Assess ; 196(2): 205, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279028

RESUMO

Permeable pavements help reduce surface temperatures and have been widely implemented in urban areas. This study utilized an in-use permeable pavement sidewalk in front of a mass rapid transit station in the Taipei city center of Taiwan to determine the actual pavement surface temperature performance. A neighboring asphalt road and impervious pavement were also monitored. With a full year of continuous monitoring, the results showed that the temperature of permeable pavement was 3.7 °C lower than that of impervious pavement and 4.5 °C lower than that of asphalt pavement in the hot season. The frequent rainfall in spring resulted in the smallest temperature differences between the different pavement types. The cooling effects of permeable pavement differed at the different air temperatures. At air temperatures lower than 15 °C, the differences among pavement surface temperatures were noticeable. However, when the air temperature was higher than 35 °C, the surface temperature of permeable pavement was not different from that of impervious pavement and was greater than 55 °C. Field observations were carried out to determine the effects on the apparent temperature and the future surface temperature of climate change scenarios. The results showed that permeable pavement could reduce the average apparent temperature to near the air temperature, and asphalt pavement could increase the apparent temperature by 1.2 °C, assuming that the pavement temperature completely affects the air temperature. With the good prediction ability of the machine learning approach and 15 environmental factors, the preliminary prediction showed the projected surface temperature change in Taipei city in 2033. In the worst-case scenario, the average impervious pavement temperature is as high as 39.12 °C, whereas the average permeable pavement temperature is 32.50 °C.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos , Chuva , Temperatura , Movimentos da Água
3.
Neuroimage Clin ; 31: 102763, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34280836

RESUMO

PURPOSE: Focal cortical dysplasia (FCD) is a major cause of drug-resistant epilepsy; however the underlying epileptogenic mechanisms of FCD metabolism in epilepsy patients remain unclear. The aim of this study is to detect alterations of γ-aminobutyric acid (GABA), glutathione (GSH), and the composite of glutamate and glutamine (Glx) in MRI-typical and neuropathologically confirmed FCD-associated epilepsy using Hadamard Encoding and Reconstruction of Mega-Edited Spectroscopy (HERMES). MATERIALS AND METHODS: Fourteen epileptic patients suspected to be caused by FCD and 14 healthy controls were enrolled prospectively in this study; all subjects underwent a 3 T MRI scan, including 3D T1 weighted imaging and HERMES. The GABA signal detected by HERMES also contains signals from macromolecules and homocarnosine, so it is referred as GABA+. Signals of GABA+, GSH and Glx detected by HERMES from tumor foci, contralateral cerebral regions, and healthy controls were quantified using Gannet. Fitting errors and signal to noise ratios (SNRs) of GABA + signals were also recorded. Differences of GABA+, GSH, Glx, fitting error and SNR of GABA + among three groups were analyzed using linear mixed effects models. RESULTS: Twelve FCD-associated epilepsy patients (7 females, aged 21.9 ± 9.3 years) and 12 matched healthy controls (7 females, aged 22.8 ± 9.8 years) were finally enrolled in this study. ANOVA results indicated that GABA levels were significantly increased in FCD foci compared with contralateral regions (p = 0.008) and with healthy controls (p = 0.003), while no difference was found in GSH and Glx levels. No difference of fitting errors or SNR of GABA + was found among FCD foci, contralateral regions and healthy controls. CONCLUSIONS: Increased GABA levels were found in FCD foci that indicated GABA may play a central role in the pathophysiology of FCD patients with epilepsy.


Assuntos
Epilepsia , Malformações do Desenvolvimento Cortical , Epilepsia/diagnóstico por imagem , Feminino , Glutationa , Humanos , Imageamento por Ressonância Magnética , Malformações do Desenvolvimento Cortical/complicações , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Ácido gama-Aminobutírico
4.
Nat Sci Sleep ; 13: 527-536, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33976578

RESUMO

OBJECTIVE: The purpose of this study was to illustrate the electrophysiological features of sleep disturbances in patients with anti-leucine-rich glioma-inactivated protein 1 (anti-LGI1) encephalitis in both active and recovery stages. METHODS: Retrospectively filed video electroencephalogram (VEEG) and polysomnography (PSG) data in 24 patients with anti-LGI1 encephalitis were analyzed in comparison with that in 20 individuals without sleep disorders as control group. RESULTS: Sleep efficiency (SE) and total sleep time involving REM and NREM sleep were significantly decreased in patients with anti-LGI1 encephalitis during the active stage compared to that during the recovery stage and in the control group. Imbalanced sleep structure was found, demonstrated by elevated N1, decreased N3 and REM components, as well as abnormal N2 structure characterized with significantly lower spindle duration and density during the active stage. These findings were independent of the presence of nocturnal episodic events or sleep hyperkinetic movements (HMs). HMs were present in 11/23 patients throughout NREM and REM sleep (nonspecific in sleep stages) during the active stage. During the recovery stage, SE and sleep structures were dramatically improved, including the percentage of N3 and REM sleep, spindle duration and density. Ten of 11 patients with HMs were followed up. HMs were totally remitted in 3 patients and still persistent in 1, while evolved into REM sleep behavior disorder (RBD) in 4 with comorbid periodic limb movement syndrome (PLMS) in 3/4, and only PLMS in 2. CONCLUSION: Sleep disturbances were remarkable and intrinsic features in active anti-LGI1 encephalitis, marked by overall disruptions of both NREM and REM sleep, as well as the presence of HMs, which tend to evolve into RBD or PLMS during the recovery stage. Long-term follow-up with PSG is needed, especially for those patients with severe sleep disturbances during the active phase.

5.
J Clin Med ; 10(7)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915706

RESUMO

Heart failure (HF) is a common presentation in patients with type 2 diabetes mellitus (T2DM). Previous studies revealed that the HbA1c level is significantly associated with HF. However, little is known about the association between HbA1c variability and HF. We aimed to evaluate the association of mean and variability of HbA1c with HF in patients with T2DM. Using Diabetes Share Care Program data, patients with T2DM who had mean HbA1c (HbA1c-Mean), and HbA1c variability (tertiles of HbA1c-SD and HbA1c-adjSD) within 12-24 months during 2001-2008 were included. The cutoffs of HbA1c-Mean were set at <7%, 7-7.9%, and ≥8%. Hazard ratios (HRs) for HF during 2008-2018 were estimated using Cox proportional hazard models. A total of 3824 patients were included, of whom 315 patients developed HF during the observation period of 11.72 years. The associated risk of HF increased with tertiles of HbA1c variability and cutoffs of HbA1c-Mean. In mutually adjusted models, HbA1c-Mean showed a consistent dose-response association with HF, while the association of HbA1c variability with HF disappeared. Among patients with HbA1c-Mean <7%, the associated risk of HF in patients with HbA1c variability in tertile 3 was comparable to patients with HbA1c-Mean ≥8%. In conclusion, mean HbA1c was an independent predictor of HF and not explained by HbA1c variability. In addition to absolute HbA1c level, targeting on stability of HbA1c in patients with good glycemic control was also important for the development of HF in patients with T2DM.

6.
Neuropsychiatr Dis Treat ; 16: 1285-1293, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547032

RESUMO

PURPOSE: Late-onset epilepsy due to autoimmune dysfunction has been reported. However, definitive diagnosis requires positive antibody results. As a result, patients with negative antibody results, but presenting with classical manifestation of autoimmune epilepsy, may be managed as suspected cases. In this study, we aim to isolate and profile the concentration of cytokines/chemokines in the cerebrospinal fluid (CSF) and the serum to ascertain if they could act as alternative diagnostic biomarkers. PATIENTS AND METHODS: Twenty patients aged ≥50 years were considered in this study. Ten patients were diagnosed with suspected autoimmune epilepsy (sAE) based on clinic manifestation, electroencephalogram, magnetic resonance imaging, and with negative antibody results of the serum and the CSF. The equivalent control group exhibited neurological disorders due to non-inflammatory pathologies. Serum and CSF were analyzed for cytokines/chemokines concentration, including interleukin (IL)-6, IL-10, IL-17, chemokine (C-X-C motif) ligand (CXCL)12 and CXCL13, as well as high-mobility group box protein 1 (HMGB1) and B cell activation factor (BAFF)). RESULTS: The CSF levels of IL-6, IL-17, HMGB1, and CXCL12 were significantly higher in the sAE group than in the control group. There was no difference in the CSF levels of IL-10, CXCL13 and BAFF. The serum levels of HMGB1 and CXCL12 were elevated in the sAE group compared with the control group, and there was no statistical difference in the serum levels of IL-6, IL-10, IL-17, CXCL13, and BAFF between the two groups. CONCLUSION: Our study shows that cytokines/chemokines may act as alternative biomarkers for diagnosis of sAE. The activation of both HMGB1/CXCL12-mediated immunity and T helper cells 17 (Th17) cells may be playing a central role in the pathogenesis of sAE. We suggest that cytokines/chemokines be treated as adjuvant biomarkers, instead of solely relying on antibody screening test. However, a larger cohort in a prospective approach is required to validate our findings.

7.
Seizure ; 76: 22-27, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31972532

RESUMO

PURPOSE: The purpose of this study was to characterize the spectrum of motor events in patients with acute anti-leucine-rich glioma-inactivated protein 1 (anti-LGI1) encephalitis through video-electroencephalogram (VEEG) recordings. METHOD: We collected data retrospectively from 16 patients diagnosed with anti-LGI1 encephalitis who had completed VEEG recording during hospitalization. RESULTS: VEEG monitoring lasted a median of 11.0 h (range 4.5∼20). Fourteen types of seizures were recorded in 9 patients (56.3 %). Eight of the 14 types of seizures demonstrated typical ictal EEG evolution (including 2 subclinical seizures), 3/14 demonstrated EEG electrodecremental events (EDE) at onset but without further evolution, and 3/14 could be only judged by analyzing semiology. FBDS was recorded in 6 patients (37.5 %), and all these attacks were followed by epileptic seizures. Simple hyperkinetic movements (HMs), such as jerk-like or twisting movements, were found in 8 (50 %) patients, and 6 of them had complex HMs, such as manipulating movements or mimics of daily activities, during sleep. CONCLUSIONS: 1. Atypical seizures, for instance, seizures without EEG evolution, are not rare but likely to be overlooked. 2. FBDS is closely linked with epileptic seizures, revealing FBDS to be a part of epileptic attacks. 3. HMs could expand the spectrum of motor manifestations, overlapping with sleep disorders. 4. The high prevalence of these motor events might be due to the disrupted cortical-subcortical network, which is critical in motor control and sleep.

8.
Neuropsychiatr Dis Treat ; 15: 2909-2915, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632040

RESUMO

BACKGROUND: Although antibody-mediated immune responses are considered pathogenic and responsible for neural injury in anti-leucine-rich glioma-inactivated protein 1 (anti-LGI1) encephalitis, previous studies have indicated that cytokines and chemokines might play roles in the pathogenic process by serving as B cell enhancers. In this study, we detected the profiles of cytokines and chemokines in the cerebral fluid (CSF) and serum of patients with anti-LGI1 encephalitis to identify potential biomarkers. METHODS: Sixteen patients diagnosed with anti-LGI1 encephalitis and nine patients diagnosed with noninflammatory neurologic disorders were included in the study. Cytokines and chemokines including IL-6, IL-10, IL-17, CXCL12, CXCL13, BAFF and HMGB1 in serum and CSF were measured. RESULTS: The serum and CSF levels of CXCL13 were significantly higher in patients with anti-LGI1 encephalitis (36.32±34.71 pg/mL and 2.23±2.41 pg/mL, respectively) than in controls (10.84±5.02 pg/mL and 0.34±0.21 pg/mL, respectively). There was no significant difference in serum or CSF levels of IL-6, IL-10, IL-17, CXCL12, BAFF and HMGB1 between the two groups. CONCLUSION: CXCL13 is a potential biomarker of active inflammation in anti-LGI1 encephalitis. The distinctive response of cytokines and chemokines might be closely linked to the mechanisms underlying this condition.

10.
BMC Ophthalmol ; 19(1): 48, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30744702

RESUMO

BACKGROUND: Painful ophthalmoplegia can be caused by various etiologies, and broad differential diagnosis is needed. Carotid-cavernous fistula (CCF) is a rare cause of painful ophthalmoplegia, and early diagnosis is quite difficult. CASE PRESENTATION: Here, we present a case of paroxysmal painful ophthalmoplegia caused by CCF. The episodic symptoms were nonstereotypical and lasted minutes to hours. Magnetic resonance imaging (MRI) and computed tomography angiography (CTA) results were normal, which confounded efforts to determine a diagnosis. Subsequently, digital subtraction angiography (DSA) revealed a posterior-draining CCF. The CCF was treated at an early stage without residual symptoms. CONCLUSIONS: We propose that symptoms could be relapsing or remitting during an early stage of CCF and that posterior-draining CCF is prone to misdiagnosis due to atypical manifestations. Normal CTA results cannot exclude carotid-cavernous fistula, and DSA should be performed once CCF is suspected.


Assuntos
Fístula Carótido-Cavernosa/diagnóstico , Síndrome de Tolosa-Hunt/diagnóstico , Angiografia Digital , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade
12.
Exp Ther Med ; 16(3): 2633-2638, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30210608

RESUMO

The recombinant adeno-associated virus human thioredoxin-PR39 (rAAV/hTRX-PR39) has been demonstrated to have a protective effect on hypoxic cells. The present study aimed to explore the potential effect of rAAV/hTRX-PR39 on acute cerebral infarction in rats. Middle cerebral artery occlusion (MCAO) model rats were produced and divided into three groups: Normal saline group, empty virus group (rAAV, without hTRX-PR39 cDNA) and rAAV/hTRX-PR39 group. Hematoxylin and eosin staining and electron microscopy observation were used to assess the morphological changes of ischemic brain tissue during different periods. Immunohistochemistry was employed to detect the expression of CD34 to reflect angiogenesis of ischemic brain tissue. Rats treated with rAAV/hTRX-PR39 showed an alleviated degree of ischemic brain edema relative to that in control groups, suggesting PR39 can ameliorate brain damage after cerebral ischemia. In the rAAV/hTRX-PR39 group, CD34-positive cells were significantly increased in ischemic brain tissues compared to control groups. Furthermore, CD34-positive cells were primarily observed around the perivascular in ischemic brain, indicating the angiogenesis role of PR39 in ischemic brain. The present findings suggest that PR39 could effectively ameliorate ischemic brain damage and promote angiogenesis, which may contribute to the treatment of acute cerebral infarction.

13.
Materials (Basel) ; 11(6)2018 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-29890755

RESUMO

Surface roughness of electrodes plays a key role in the dielectric breakdown of thin-film organic devices. The rate of breakdown will increase when there are stochastic sharp spikes on the surface of electrodes. Additionally, surface having spiking morphology makes the determination of dielectric strength very challenging, specifically when the layer is relatively thin. We demonstrate here a new approach to investigate the dielectric strength of organic thin films for organic light-emitting diodes (OLEDs). The thin films were deposited on a substrate using physical vapor deposition (PVD) under high vacuum. The device architectures used were glass substrate/indium tin oxide (ITO)/organic material/aluminum (Al) and glass substrate/Al/organic material/Al. The dielectric strength of the OLED materials was evaluated from the measured breakdown voltage and layer thickness.

14.
Neurochem Res ; 43(3): 591-599, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29497903

RESUMO

This study aimed to study the protective effect of (2R,4R)-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC), a selective metabotropic glutamate receptor agonist, against hippocampal neuronal apoptosis induced by seizures in a rat model of pilocarpine-induced epilepsy. The Morris water maze test was used to assess the spatial memory abilities of epileptic rats with or without 2R,4R-APDC treatment. TUNEL assay was performed to examine neuronal apoptosis in hippocampus. Western blot was conducted to evaluate changes in the levels of caspase-3 and caspase-9 in hippocampus. Real-time PCR was used to determine the levels of microRNA-128 (miR-128) in hippocampus. The results of the Morris water maze test showed that the 2R,4R-APDC treatment reduced the escape latencies and swimming lengths of rats after seizures. The TUNEL assay showed that 2R,4R-APDC significantly counteracted seizure-induced cell apoptosis. The western blot confirmed this finding, demonstrating that the levels of cleaved caspase-3 and cleaved caspase-9 were potently decreased by 2R,4R-APDC in rat hippocampus after seizures. In addition, 2R,4R-APDC upregulated miR-128 expression levels in the hippocampus. A miR-128 mimic or inhibitor decreased or increased the percentage of TUNEL-positive cells in rats after seizures and 2R,4R-APDC treatment, respectively. The levels of both cleaved caspase-3 and cleaved caspase-9 were decreased in hippocampus exposed to the miR-128 mimic, whereas they were markedly increased in miR-128 inhibitor-treated hippocampus. In conclusion, 2R,4R-APDC protected hippocampal cells from cell apoptosis after seizures, possibly by upregulating miR-128.


Assuntos
MicroRNAs/metabolismo , Prolina/análogos & derivados , Receptores de Glutamato Metabotrópico/agonistas , Regulação para Cima/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Agonistas de Aminoácidos Excitatórios/farmacologia , Hipocampo/metabolismo , Masculino , Memória/efeitos dos fármacos , Prolina/farmacologia , Ratos Sprague-Dawley , Convulsões/tratamento farmacológico , Convulsões/metabolismo
15.
Neurosci Lett ; 638: 145-150, 2017 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-27993708

RESUMO

Parkinson's disease (PD) is characterized by the loss of neuromelanin (NM)-containing neurons in the substantia nigra pars compacta (SNc), and it is divided into two motor subtypes: the postural instability gait difficulty (PIGD) and the tremor dominant (TD) subtypes. With NM-sensitive Magnetic Resonance Imaging (NM-MRI), investigators have been able to accurately detect signal attenuation in SNc of PD; however, the difference of NM loss between PIGD and TD subtypes is still unclear. Thus, the aim of this study was to evaluate the differences in NM-MRI between PD motor subtypes. PD patients were classified into PIGD (n=14) and TD groups (n=9); 20 age and sex matched controls were recruited. We compared the signal intensity contrast ratios in medial and lateral regions of the SNc using NM-MRI in PIGD, TD, and controls, respectively. Remarkable signal attenuation was observed in the lateral part of SNc in PD when compared with the controls, and we were able to detect more severe signal attenuation in the medial part of SNc in PIGD patients in comparison with that in the TD group. Also, the medial part of SNc, ipsilateral to the most clinically affected side, showed the highest power to discriminate the PD motor subtypes (AUC, 81%; sensitivity, 71.4%; specificity, 77.8%). Our results indicated a potential diagnostic value of NM-MRI to discriminate the PD motor subtypes, providing new evidence for the neuropathology-based differences between the two subtypes.


Assuntos
Melaninas/metabolismo , Doença de Parkinson/fisiopatologia , Parte Compacta da Substância Negra/metabolismo , Idoso , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Parte Compacta da Substância Negra/diagnóstico por imagem , Estudos Prospectivos
16.
Sensors (Basel) ; 16(8)2016 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-27509507

RESUMO

This study proposes a new behavioral simulator that uses SIMULINK for all-digital CMOS time-domain smart temperature sensors (TDSTSs) for performing rapid and accurate simulations. Inverter-based TDSTSs offer the benefits of low cost and simple structure for temperature-to-digital conversion and have been developed. Typically, electronic design automation tools, such as HSPICE, are used to simulate TDSTSs for performance evaluations. However, such tools require extremely long simulation time and complex procedures to analyze the results and generate figures. In this paper, we organize simple but accurate equations into a temperature-dependent model (TDM) by which the TDSTSs evaluate temperature behavior. Furthermore, temperature-sensing models of a single CMOS NOT gate were devised using HSPICE simulations. Using the TDM and these temperature-sensing models, a novel simulator in SIMULINK environment was developed to substantially accelerate the simulation and simplify the evaluation procedures. Experiments demonstrated that the simulation results of the proposed simulator have favorable agreement with those obtained from HSPICE simulations, showing that the proposed simulator functions successfully. This is the first behavioral simulator addressing the rapid simulation of TDSTSs.

17.
Exp Ther Med ; 9(5): 1605-1610, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26136866

RESUMO

The aim of the present study was to successfully construct a recombinant adeno-associated virus (rAAV) vector containing the human thioredoxin (hTRX)-PR39 chimeric gene (rAAV/hTRX-PR39), and verify that the vector was able to maintain a sustained, stable and efficient expression to achieve protein production in the cell. In the present study, a chicken embryo model was utilized to analyze the therapeutical effect of rAAV/hTRX-PR39 in cerebral ischemia diseases. ECV304 cells were transfected with rAAV/hTRX-PR39 and incubated under conditions of 20, 5 and 1% O2. Subsequently, the expression levels of vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor (VEGFR)-1, VEGFR-2, fibroblast growth factor receptor (FGFR)-1 and syndecan-4 were detected by reverse transcription-quantitative polymerase chain reaction. Under hypoxic conditions, the mRNA expression levels of VEGF, VEGFR-1, VEGFR-2, FGFR-1 and syndecan-4 were found to increase in the PR39-transfected group when compared with the control group, while no statistically significant difference was observed between the PR39-transfected group and the control group under conditions of 20% O2. In addition, hTRX-PR39 was shown to increase the density of the vasculature and the survival rate of the chick embryos. Under hypoxic conditions, it was hypothesized that rAAV/hTRX-PR39 was capable of promoting angiogenesis, which may subsequently protect the cells from impairment by hypoxia. In conclusion, rAAV/hTRX-PR39 was demonstrated to promote vascularization and cell survival in hypoxia; thus, rAAV/hTRX-PR39 may have potential for use in therapy targeting cerebral ischemia.

18.
Rev Sci Instrum ; 86(12): 126113, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26724094

RESUMO

This paper presents an all-digital CMOS pulse-shrinking mechanism suitable for time-to-digital converters (TDCs). A simple MOS capacitor is used as a pulse-shrinking cell to perform time attenuation for time resolving. Compared with a previous pulse-shrinking mechanism, the proposed mechanism provides an appreciably improved temporal resolution with high linearity. Furthermore, the use of a binary-weighted pulse-shrinking unit with scaled MOS capacitors is proposed for achieving a programmable resolution. A TDC involving the proposed mechanism was fabricated using a TSMC (Taiwan Semiconductor Manufacturing Company) 0.18-µm CMOS process, and it has a small area of nearly 0.02 mm(2) and an integral nonlinearity error of ±0.8 LSB for a resolution of 24 ps.

19.
Cell Mol Neurobiol ; 34(6): 813-24, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24832394

RESUMO

Temporal lobe epilepsy is characterized by spontaneous recurrent seizures (SRS) and associated with behavioral problems. However, the molecular mechanisms underlying these problems are not yet clear. In this study, kainic acid (KA) was systemically administered to immature male Wistar rats to induce SRS. The behavior of the immature rats was evaluated with a water maze, elevated-plus mazes, and open field tests. The expression patterns of synaptophysin, SNAP-25, and synaptotagmin 1 (Syt 1) were examined by reverse-transcriptase polymerase chain reaction (RT-PCR) and Western blot analysis. KA-treated rats with SRS demonstrated learning and memory deficits, reduced anxiety, and increased locomotor activity, compared with placebo-treated rats and KA-treated rats without SRS. No neuronal cell loss was observed in the hippocampus 6 weeks after exposure to KA. However, RT-PCR and Western blot analyses revealed decreased synaptophysin, SNAP-25, and Syt 1 expression in KA-treated rats with SRS. Synaptophysin, SNAP-25, and Syt1 expression levels were found to be positively correlated with learning and memory but negatively correlated with anxiety and locomotor activity. These data suggested that SRS may induce changes in synaptophysin, SNAP-25, and Syt1 expression and may be functionally related to SRS-induced behavioral deficits.


Assuntos
Comportamento Animal/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Transtornos da Memória/metabolismo , Sinaptofisina/metabolismo , Proteína 25 Associada a Sinaptossoma/metabolismo , Sinaptotagmina I/metabolismo , Animais , Ácido Caínico/farmacologia , Aprendizagem/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Memória/fisiologia , Transtornos da Memória/induzido quimicamente , Ratos Wistar
20.
Brain Res ; 1535: 14-23, 2013 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-23994215

RESUMO

Intense poly(ADP-ribose) polymerase-1 (PARP-1) activation was implicated as a major cause of caspase-independent cell death in the hippocampal neuronal culture (HNC) model of acute acquired epilepsy (AE). The molecular mechanisms are quite complicated. The linkage among neuronal death, cellular nicotinamide adenine dinucleotide (NAD) levels, apoptosis-inducing factor (AIF) translocation, SIRT1 expression and activity were investigated here. The results showed that PARP-1 over-activation caused by Mg²âº-free stimuli led to cellular NAD depletion which could block AIF translocation from mitochondria to nucleus and attenuate neuronal death. Also, SIRT1 deacetylase activity was reduced by Mg²âº-free treatment, accompanied by elevated ratio of neuronal death, which could be rescued by NAD repletion. These data demonstrated that cellular NAD depletion and decline of SIRT1 activity play critical roles in PARP-1-mediated epileptic neuronal death in the HNC model of acute AE.


Assuntos
Morte Celular , Epilepsia/metabolismo , NAD/metabolismo , Neurônios/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Sirtuína 1/metabolismo , Animais , Fator de Indução de Apoptose/metabolismo , Epilepsia/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Neurônios/patologia , Poli(ADP-Ribose) Polimerase-1 , Ratos
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