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Objective: To establish a detection method based on Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) that can sensitively detect the second messenger cyclic AMP (cAMP) in the cytoplasm. Methods: The eukaryotic expression vectors of CFTR and YFP-H148Q / I152L were constructed respectively. FRT cells co-expressing CFTR and YFP-H148Q / I152L were obtained by liposome transfection. The expression of CFTR and YFP-H148Q / I152L in FRT cells was observed by an inverted fluorescence microscopy, and flow cytometry was used to detect the purity of cells; The cell model was identified by the fluorescence quenching kinetics test. The validation of the cell model which could screen CFTR modulators was verified by the fluorescence quenching kinetics experiments. The radioimmunoassay was used to detect the cAMP concentration in cytoplasm after adding CFTR activator. Results: The results of the inverted fluorescence microscope showed that CFTR was expressed in the cell membrane and YFP-H148Q / I152L was expressed in the cytoplasm of FRT cells. The FRT cell model stably co-expressing ANO1 and YFP-H148Q / I152L was successfully constructed. The model could screen CFTR modulators, and the slope of fluorescence change and the concentration of CFTR modulators were in a dose-dependent manner. The slope of the fluorescence could reflect the cAMP concentration in the cytoplasm. The cell model could sensitively detect the intracellular cAMP concentration. Conclusion: The cell model could efficiently and sensitively detect the second messenger cAMP concentration in the cytoplasm, and it provided a simple and efficient method for the study of other targets associated cAMP signal.
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AMP Cíclico , Regulador de Conductancia de Transmembrana de Fibrosis Quística , Citoplasma , Sistemas de Mensajero SecundarioRESUMEN
The current study employed an eye-movement technique with an attempt to explore the reading patterns for the two types of Chinese relative clauses, subject-extracted relative clauses (SRCs) and object-extracted relative clauses (ORCs), by native speakers (L1), and Japanese learners (L2) of Chinese. The data were analyzed in terms of gaze duration, regression path duration, and regression rate on the two critical regions, head noun, and embedded verb. The results indicated that both the L1 and L2 participants spent less time on the head nouns in ORCs than in SRCs. Also, the L2 participants spent less time on the embedded verbs in ORCs than in SRCs and their regression rate for embedded verbs was generally lower in ORCs than in SRC. The findings showed that the participants experienced less processing difficulty in ORCs than SRCs. These results suggest an ORC preference in L1 and L2 speakers of Chinese, which provides evidence in support of linear distance hypothesis and implies that the syntactic nature of Chinese is at play in the RC processing.
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A number of previous studies on Chinese relative clauses (RC) have reported conflicting results on processing asymmetry. This study aims to revisit the prevalent debate on whether subject-extracted RCs (SRC) or object-extracted RCs (ORC) are easier to process by using the eye-movement technique. In the current study, the data are analyzed in terms of the gaze duration and regression of eye-movement in three critical areas: head noun, embedded verb, and RC-modifying noun phrase as subject. The results show an ORC preference for the processing of RC structures, which supports the word-order account and the Dependency Locality Theory, and a better cross-clausal integration for SRC, which supports the perspective-shift account. The processing asymmetry in Chinese RCs are discussed under relevant theoretical accounts, such as structure-based, memory-based, and perspective shift accounts. We argue that the findings are associated with the syntactic nature of Chinese (a head-initial language with pre-nominal RCs).
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Comprensión/fisiología , Medidas del Movimiento Ocular , Psicolingüística/métodos , Desempeño Psicomotor/fisiología , Lectura , Adolescente , Adulto , Femenino , Humanos , Masculino , Taiwán , Adulto JovenRESUMEN
Online reading is developing at an increasingly rapid rate, but the debate concerning whether learning is more effective when using hypertexts than when using traditional linear texts is still persistent. In addition, several researchers stated that online reading comprehension always starts with a question, but little empirical evidence has been gathered to investigate this claim. This study used eye-tracking technology and retrospective think aloud technique to examine online reading behaviors of fifth-graders (N = 50). The participants were asked to read four texts on the website. The present study employed a three-way mixed design: 2 (reading ability: high vs. low) × 2 (reading goals: with vs. without) × 2 (text types: hypertext vs. linear text). The dependent variables were eye-movement indices and the frequencies of using online reading strategy. The results show that fifth-graders, irrespective of their reading ability, found it difficult to navigate the non-linear structure of hypertexts when searching for and integrating information. When they read with goals, they adjusted their reading speed and the focus of their attention. Their offline reading ability also influenced their online reading performance. These results suggest that online reading skills and strategies have to be taught in order to enhance the online reading abilities of elementary-school students.
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PURPOSE: The interaction between the sagittal alignment of the spine and pelvis and the compensatory mechanism in patients suffering from spinal disorders has been well documented. However, in patients with hip osteoarthritis (HOA), few studies have explored how the hip joint pathology could affect the sagittal alignment of the hip, pelvis and spine, and no reports have investigated whether these changes are involved in the pathogenesis of low back pain in these patients. The aims of this case-control study were to investigate the sagittal spine-pelvis-leg alignment in patients suffering from severe HOA and to understand whether the alignment was related to the occurrence of low back pain and the health-related quality of life in these patients. METHODS: Fifty-eight patients with severe HOA and 64 asymptomatic controls were studied. Digital lateral X-rays of the spine, pelvis and proximal femur were obtained with the patients placed in upright positions. The following radiographic parameters were measured to examine the sagittal alignment of the pelvis, hip and spine: pelvic incidence (PI), pelvic tilting (PT), sacral slope (SS), pelvic femoral angle (PFA), femoral inclination (FI), lumbar lordosis (LL), spino-sacral angle (SSA), C7 tilt (C7T) and T1 spinal-pelvic inclination (T1-SPI). The global balance patterns of spinal-pelvic alignment were classified as normal balance, slight unbalance and severe unbalance according to the relative position of the C7 plumb line to the sacrum and femoral heads. Short Form-36 questionnaire was carried out in the patients. Comparisons were carried out between the patients with HOA and the controls and between the HOA patients with or without low back pain. Correlation analysis was used to measure relationships between the HOA patients' parameters. RESULTS: There were no significant differences in the age and gender distribution between the HOA patients and control. Compared with the controls, the patients with HOA showed significantly higher SS and lower PT, similar PI in the pelvis, significantly smaller C7T, larger T1-SPI but comparable LL and SSA in the spine, and significantly smaller PFA but larger FI in the hip joint. In addition, the patients with HOA had a significantly greater incidence of severe unbalanced spinal-pelvic alignment than did the controls (22.4 vs 3.1 %, respectively). In patients with HOA, the PFA was significantly correlated with SS, SSA and FI but not with PI, LL or C7T; while the physical component score of short form-36 was significantly correlated with T1-SPI, C7T and FI. A comparison between the HOA patients with or without low back pain, however, showed no significant differences in the radiographic parameters, global sagittal balance patterns and Short Form-36. CONCLUSIONS: The sagittal morphology of the pelvis in patients with severe HOA was normal and might not be involved in the development and progression of this disorder. Although the whole spine was involved in compensating for the flexed hip joint, the poor ability resulted in severely unbalanced spinal-pelvic alignment in these patients. The forward inclined spine and retroverted femur would contribute to the poor physical activities in these patients. However, the abnormal sagittal spine-pelvis-leg alignment in patients with severe HOA might not be involved in the pathogenesis of low back pain.