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1.
Eur J Intern Med ; 24(8): 835-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23988262

ABSTRACT

BACKGROUND: Hepatitis B virus-associated glomerulonephritis (HBV-GN) is a kind of immune complex-induced glomerulonephritis. The present study was designed to determine whether Hepatitis B virus (HBV) genotype is associated with glomerulonephritis in north-west Chinese children. METHODS: A total of 296 HBV-infected patients were enrolled in this study. The serum of patients was subjected to DNA extraction and the HBV genotypes were determined by PCR. RESULTS: The results showed that genotype C (49%) was predominant within the subjects, compared to HBV/B (38.5%), B/C recombinant (7.4%) and none B/C (5.1%). The serum tests showed that the changes of Complement 3 (C3) and alanine amino transferase (ALT) levels in the genotype C patients were significantly greater than those in the genotype B patients. The frequency of genotype C in HBV-GN patients was higher than that in non HBV-GN patients (χ2 value=30.239, P<0.001). But, it was not associated with renal dysfunction. Furthermore, The genotype C was associated with high HBV-DNA load (82.9% vs 17.1%, P<0.001), which is seen more frequently in the HBV-GN children (86.3% vs 13.3%, P=0.004). CONCLUSIONS: The genotype C may play a role in HBV-GN children, via favoring HBV replication.


Subject(s)
DNA, Viral/genetics , Glomerulonephritis/virology , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Adolescent , Alanine Transaminase , Child , Child, Preschool , China , Complement C3/immunology , Female , Genotype , Glomerulonephritis/complications , Glomerulonephritis/immunology , Hepatitis B, Chronic/complications , Hepatitis B, Chronic/immunology , Humans , Male , Viral Load
2.
Dev Cogn Neurosci ; 6: 40-50, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23872198

ABSTRACT

Previous behavioral studies have suggested that morphological awareness is impaired in Chinese children with reading disability (RD), but how this is reflected in brain alterations is not known. Using functional magnetic resonance imaging (fMRI), the current study compared morphological processing in a RD group (11-13 years old) to an age-matched typically developing (TD) group. Participants made semantic relatedness judgments to incongruent word pairs that were either semantically related but did not share a morpheme or semantically unrelated but did share a morpheme. This was compared to conditions where semantic relatedness and morphemic information was congruent. A smaller incongruency effect was found in left dorsal posterior (BA9) and ventral anterior (BA47) inferior frontal gyrus (IFG) in the RD compared to the TD, suggesting that the RD is less sensitive to morphological information. This was a specific deficit as a phonological control task that manipulated congruency between orthography and phonology did not show group differences in the IFG. Moreover, brain activation in the IFG for the incongruency effect in the semantic task was negatively correlated with reading skill for the RD group only, suggesting that higher skill children with RD may rely on a compensatory whole-word strategy by ignoring the morphemic information.


Subject(s)
Brain/pathology , Brain/physiopathology , Dyslexia/physiopathology , Reading , Semantics , Adolescent , Brain Mapping , Child , China , Dyslexia/pathology , Female , Frontal Lobe/pathology , Frontal Lobe/physiopathology , Humans , Judgment , Magnetic Resonance Imaging , Male , Phonetics
3.
Neuropsychologia ; 51(7): 1169-76, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23542499

ABSTRACT

Due to the logographic nature of the writing system, learning to read Chinese places heavy demands on encoding of orthographic forms through rote memorization. Moreover, phonology has to often be retrieved from memory during reading because of the inconsistent mapping between characters and their pronunciations. Using optimized voxel-based morphometry, we examined differences in volumetrics between children with reading disability (RD, 10-12 years old) and age-matched typically developing (TD) children. Our study shows reduced gray matter volume (GMV) for RD in right inferior occipital gyrus and left inferior frontal gyrus, consistent with previous studies suggesting that Chinese dyslexics have deficits in orthographic and phonological processing. The deficit in phonological processing was further supported by reductions in white matter volumes (WMV) in left precentral gyrus. Greater deficits in ortho-phonological processing may be associated with semantic compensation, as lower skill RD children showed greater GMV in anterior temporal cortex, even though as a group they showed less GMV in this region compared to TD. Perhaps most interestingly, we showed reduced GMV in bilateral ventromedial prefrontal cortices (vmPFC) and this was correlated with reductions in WMV within vmPFC, suggesting that RD have deficits in memory retrieval. Moreover, these GMV alterations in vmPFC for the RD were correlated with alterations in right parahippocampal gyrus, which also showed a reduced GMV, suggesting that RD have a correlated deficit in memory encoding. Our results are consistent with previous studies suggesting that Chinese dyslexics have deficits in visuo-orthographic and phonological processing, but our study importantly suggests deficits in memory encoding and retrieval, perhaps due to the unique demands of the Chinese writing system.


Subject(s)
Brain Mapping , Brain/pathology , Dyslexia/pathology , Adolescent , Case-Control Studies , Child , China , Female , Functional Laterality , Humans , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Male , Nerve Fibers, Myelinated/pathology , Reading , Regression Analysis
4.
Q J Exp Psychol (Hove) ; 66(10): 2023-38, 2013.
Article in English | MEDLINE | ID: mdl-23510000

ABSTRACT

English words with an inconsistent grapheme-to-phoneme conversion or with more than one pronunciation ("homographic heterophones"; e.g., "lead"-/lεd/, /lid/) are read aloud more slowly than matched controls, presumably due to competition processes. In Japanese kanji, the majority of the characters have multiple readings for the same orthographic unit: the native Japanese reading (KUN) and the derived Chinese reading (ON). This leads to the question of whether reading these characters also shows processing costs. Studies examining this issue have provided mixed evidence. The current study addressed the question of whether processing of these kanji characters leads to the simultaneous activation of their KUN and ON reading, This was measured in a direct way in a masked priming paradigm. In addition, we assessed whether the relative frequencies of the KUN and ON pronunciations ("dominance ratio", measured in compound words) affect the amount of priming. The results of two experiments showed that: (a) a single kanji, presented as a masked prime, facilitates the reading of the (katakana transcriptions of) their KUN and ON pronunciations; however, (b) this was most consistently found when the dominance ratio was around 50% (no strong dominance towards either pronunciation) and when the dominance was towards the ON reading (high-ON group). When the dominance was towards the KUN reading (high-KUN group), no significant priming for the ON reading was observed. Implications for models of kanji processing are discussed.


Subject(s)
Perceptual Masking/physiology , Phonetics , Psycholinguistics , Reading , Acoustic Stimulation , Adolescent , Female , Humans , Male , Reaction Time/physiology , Young Adult
5.
PLoS One ; 7(10): e46595, 2012.
Article in English | MEDLINE | ID: mdl-23056360

ABSTRACT

Four experiments investigated the role of the syllable in Chinese spoken word production. Chen, Chen and Ferrand (2003) reported a syllable priming effect when primes and targets shared the first syllable using a masked priming paradigm in Chinese. Our Experiment 1 was a direct replication of Chen et al.'s (2003) Experiment 3 employing CV (e.g., ,/ba2.ying2/, strike camp) and CVG (e.g., ,/bai2.shou3/, white haired) syllable types. Experiment 2 tested the syllable priming effect using different syllable types: e.g., CV (,/qi4.qiu2/, balloon) and CVN (,/qing1.ting2/, dragonfly). Experiment 3 investigated this issue further using line drawings of common objects as targets that were preceded either by a CV (e.g., ,/qi3/, attempt), or a CVN (e.g., ,/qing2/, affection) prime. Experiment 4 further examined the priming effect by a comparison between CV or CVN priming and an unrelated priming condition using CV-NX (e.g., ,/mi2.ni3/, mini) and CVN-CX (e.g., ,/min2.ju1/, dwellings) as target words. These four experiments consistently found that CV targets were named faster when preceded by CV primes than when they were preceded by CVG, CVN or unrelated primes, whereas CVG or CVN targets showed the reverse pattern. These results indicate that the priming effect critically depends on the match between the structure of the prime and that of the first syllable of the target. The effect obtained in this study was consistent across different stimuli and different tasks (word and picture naming), and provides more conclusive and consistent data regarding the role of the syllable in Chinese speech production.


Subject(s)
Language , Adolescent , Adult , Animals , China , Humans , Young Adult
6.
Neurology ; 79(7): 625-32, 2012 Aug 14.
Article in English | MEDLINE | ID: mdl-22875083

ABSTRACT

OBJECTIVES: The aim of the current study was to differentiate between neural activity that represents neural anomalies that are responsible for persistent developmental stuttering (PDS) from the activity that is a result of compensating for stuttering. This was done by investigating alterations to the intrinsic functional architecture of speech-language processes of patients with PDS before and after a short-term intervention. METHODS: The resting-state functional connectivity (RSFC) and cortical thickness were examined before and after the intervention. The structural data were used to validate the functional results. Fifteen stuttering patients who received intervention (PDS+), 13 stuttering patients who did not receive intervention (PDS-), and 13 fluent controls participated. RESULTS: Before the intervention, both groups of PDS patients showed significant RSFC and cortical thickness reductions in the left pars-opercularis (PO) and RSFC increases in the cerebellum, as compared to fluent controls. The intervention was effective in reducing stuttering in PDS+ patients and lowering their RSFC in the cerebellum to the level of fluent controls. The intervention effect was specific to the PDS+ group (it was not evident in the PDS- group). The intervention did not change RSFC and cortical thickness in the left PO, which remained at its preintervention level. CONCLUSIONS: The results suggest that the left PO is a locus where the intrinsic functional architecture of speech-language processes is altered in PDS patients, suggesting an etiologic role of this region in PDS. The cerebellum showed intervention-induced neural reorganization, suggesting a compensatory response when stuttering occurs.


Subject(s)
Behavior Therapy , Brain/physiopathology , Nerve Net/physiopathology , Stuttering/physiopathology , Stuttering/therapy , Adult , Brain Mapping , Female , Functional Laterality/physiology , Humans , Image Processing, Computer-Assisted , Male , Speech Perception/physiology , Treatment Outcome
7.
Neuropsychologia ; 50(9): 2224-32, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22698991

ABSTRACT

Dyslexia in alphabetic languages has been extensively investigated and suggests a central deficit in orthography to phonology mapping in the left hemisphere. Compared to dyslexia in alphabetic languages, the central deficit for Chinese dyslexia is still unclear. Because of the logographic nature of Chinese characters, some have suggested that Chinese dyslexia should have larger deficits in the semantic system. To investigate this, Chinese children with reading disability (RD) were compared to typically developing (TD) children using functional magnetic resonance imaging (fMRI) on a rhyming judgment task and on a semantic association judgment task. RD children showed less activation for both tasks in right visual (BA18, 19) and left occipito-temporal cortex (BA 37), suggesting a deficit in visuo-orthographic processing. RD children also showed less activation for both tasks in left inferior frontal gyrus (BA44), which additionally showed significant correlations with activation of bilateral visuo-orthographic regions in the RD group, suggesting that the abnormalities in frontal cortex and in posterior visuo-orthographic regions may reflect a deficit in the connection between brain regions. Analyses failed to reveal larger differences between groups for the semantic compared to the rhyming task, suggesting that Chinese dyslexia is similarly impaired in the access to phonology and to semantics from the visual orthography.


Subject(s)
Brain/physiopathology , Dyslexia/psychology , Semantics , Speech Perception/physiology , Adolescent , Asian People , Child , Data Interpretation, Statistical , Female , Humans , Image Processing, Computer-Assisted , Intelligence Tests , Judgment , Magnetic Resonance Imaging , Male , Occipital Lobe/physiopathology , Reaction Time/physiology , Reading , Temporal Lobe/physiopathology , Visual Perception/physiology
8.
Acta Psychol (Amst) ; 130(3): 196-203, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19162255

ABSTRACT

Three experiments investigated age of acquisition (AoA) effects on early orthographic processing during Chinese character recognition. In Experiment 1, we measured the accuracy of identification of brief masked characters, accuracy was higher for early compared to late acquired characters. In Experiment 2, the visual duration threshold (VDT) was measured for both early and late acquired Chinese characters. The results showed that early acquired characters were successfully identified at shorter display durations than late acquired characters. Significant AoA effects were also found in Experiment 3, using a lexical decision task requiring mainly orthographic processing (discriminating real Chinese characters from orthographically illegal and unpronounceable characters). In summary, three experiments provide converging empirical evidence, for AoA effects on the early orthographic processing stages of Chinese character recognition. These results suggest that AoA effects during word identification go beyond the phonological or semantic processing stages. These results aslo provide cross-linguistic evidence for an AoA effect on early perceptual processing during identification.


Subject(s)
Asian People , Cognition , Recognition, Psychology , Verbal Learning , Adolescent , Age Factors , Discrimination Learning , Empirical Research , Humans , Phonetics , Semantics , Visual Perception , Young Adult
9.
Cognition ; 110(1): 39-50, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19091311

ABSTRACT

Frequency trajectory is a better measure to investigate age-limited learning effects than age of acquisition (AoA) ratings (Zevin, J. D., & Seidenberg, M. S. (2002). Age of acquisition effects in word reading and other tasks. Journal of Memory and Language, 47(1), 1-29). The current study uses frequency trajectory as a variable to investigate age-limited learning effects in Chinese character recognition, and tests predictions of the arbitrary mapping hypothesis as applied in a non-alphabetic writing system. In Experiment 1, regression analyses showed that, compared to rated AoA, frequency trajectory of characters was less affected by other lexical properties, and could explain a significant proportion of variance of AoA. In Experiment 2, the frequency trajectory and predictability from orthography to pronunciation of characters were orthogonally manipulated in a character naming task. The frequency trajectory effect appeared only for the arbitrary mapping condition. In Experiment 3, frequency trajectory and predictability from orthography to meaning of characters were manipulated in a semantic category judgment task. The frequency trajectory effects were found only when the mapping from orthography to semantic is less consistent. In summary, the study confirmed that AoA is a genuine factor affecting word processing, and the AoA effects were limited to those situations in which mapping between input and output representation was arbitrary. These results provide strong cross-linguistic evidence in support of the arbitrary mapping hypothesis.


Subject(s)
Learning/physiology , Reading , Recognition, Psychology/physiology , Adolescent , Aging/psychology , Female , Humans , Male , Psycholinguistics , Young Adult
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