ABSTRACT
Objective T o study the effect of different attentional conditions on the event-related potential (E R P ) com ponents generated by the visual inform ation stim uli related to visual acuity, and provide a theoretical reference for clinical forensic visual objective evaluation. Methods W ith visual acuity opto-types as norm al form of visual inform ation stim uli, 15 volunteers as study subjects w ere supposed to ac-count the visual acuity optotypes under the attentional condition of visual stim uli. Furtherm ore, the sub-jects w ere required to listen to the storytelling carefully under the non-attentional condition of visual stim uli, and after the exam ination, they needed to answ er the story-related questions. A ll the E E G re-sults of tw o different attentional conditions from the subjects w ere recorded by 32 channel E R P system . Results U nder tw o attentional conditions, P 1 and P 300 com ponents w ere evoked by the visual acuity opto-types on supra-threshold and threshold visual acuity levels, w hile only P 1 com ponent w ere evoked by the visual acuity optotypes on sub-threshold levels. In the E R P w aveform s evoked by the visual acuity optotypes on supra-threshold, P 1 and P 300 am plitudes under attentional condition w ere larger than that un-der non-attentional condition. Conclusion A ttentional conditions can influence the detection of visual acuity. P 300 com ponent can be used to distinguish the visual acuity levels w ith supra-threshold and sub-threshold under non-attentional condition.
ABSTRACT
Objective T o explore the com position characteristic of event related potential (E R P ) in dif-ferent visual acuity levels, and to provide theoretical basis for the objective assessm ent of visual acuity. Methods M onocular stim ulus w as perform ed on 16 selected subjects. T he subjects w ere required to look straight at the screen ahead and count the am ount of stim uli from different directions. T he pictures of optotype stim ulus w hich corresponding to three different visual acuity levels w ere show ed in the center of the screen. The ERP results w ere recorded separately. Results (1) The P1 am plitudes of m atch stim uli recorded under the supra-threshold visual acuity level w ere higher than that of m atch stim uli recorded under the threshold and sub-threshold visual acuity levels. T here w as no significant difference betw een the P 1 am plitudes of m atch stim uli recorded under the threshold and sub-threshold visual acuity levels. T he tendency of conflict stim uli w as sim ilar to that of m atch stim uli under three visual acuity levels. (2) In the 340-500 m s post-stim ulus range, P 300 com ponent w as found under supra-threshold and threshold visual acuity levels; no P 300 com ponent w as found in corresponding tim e w indow under sub-threshold visual acuity. T he differences of P 300 am plitudes am ong three visual acuity levels w ere statistically significant. T he am plitudes from high to low w ere the supra-threshold, threshold and sub-threshold visual acuity levels. Conclusion E R P can be a potential new m ethod for the objective assessm ent of visual acuity in forensic m edicine.
ABSTRACT
Mild cognitive im pairm ent caused by craniocerebral traum a is the key points and difficulties in judicial authentication. This article has com parative analysis of eachmode of event-related potential (classical O ddball, E riksen flanker task and so on), which can provide a more objective m ethod for such craniocerebral traum a cases in clinical forensic judicial authentication.
ABSTRACT
PurposeTo measure the areas and diameter lines of bronchi at acute exacerbation and at remission period in patients with chronic obstructive pulmonary disease (COPD) using CT, and to explore the correlation between the two periods and evaluate the comprehensive assessment in diagnosing COPD exacerbation.Materials and Methods Fifty-two COPD patients were scanned with 64-row spiral CT on chest and PFT at acute exacerbation and at remission period. The areas and diameter lines of apical segmental and the sub-segmental bronchi of the right upper lobe in the patients were measured at the two periods, including indicators such as wall thickness (WT), thickness-diameter ratio (TDR), wall area (WA), percentage of wall area (WA%). The differences of those indicators at the two periods were compared with such factors of COPD comprehensive assessment as forced expiratory volume at the first second% (FEV1%), percentage of forced expiratory volume in first second to forced vital capacity (FEV1/FVC), COPD assessment test (CAT), modified medical research council questionnaire (mMRC) for assessing the severity of breathlessness, 6-minute walking distance (6MWD). Results The patients had significant differences between acute exacerbation period and remission period in the indicators of COPD comprehensive assessment like FEV1%, FEV1/FVC, CAT, mMRC and 6MWD (t=-4.119,-2.583, 4.012, 3.321 and-3.892,P<0.05). Compared with those at remission period, the WT, TDR, WA and WA% of sub-segmental bronchi were all higher at acute exacerbation period (t=3.025, 2.341, 2.204 and 2.124, P<0.05); only TDR of segmental bronchi showed significant difference between the two periods (t=2.990,P<0.05). The correlation of sub-segmental bronchi with FEV1%, FEV1/FVC, CAT, mMRC and 6MWD was more significant than that of segmental bronchi with those indicators at the two periods.Conclusion The COPD comprehensive assessment can help diagnose COPD at acute exacerbation period; MSCT shows the remodeling of segmental and sub-segmental bronchi and the changes on the airway wall, and the quantitative measurement of sub-segmental bronchi has correlation with the differences of indicators in the comprehensive assessment; COPD comprehensive assessment seems to be more valuable than PFT in the estimation of COPD at acute exacerbation.
ABSTRACT
Objective To investigate the changes in the expression of GABAAα1, receptors in medial prefrontal cortex (mPFC) in a rat model of neuropathic pain. Methods Nine male Wistar rats weighing 200-210 g were randomly divided into 3 groups ( n = 3 each): control group (group C) , sham operation group (group S) and neuropathic pain group (group P). Neuropathic pain was induced by chronic constrictive injury. The right sciatic nerve was exposed and 4 loose ligatures were placed on the sciatic nerve at 1 mm intervals with 3-0 chromic catgut. In group S, the right sciatic nerve was exposed but not ligated. The thermal and mechanical pain threshold was measured at 1 d before and 1,4,7, 10 and 14 d after operation. The animals were then sacrificed and the mPFC was removed. The expression of GABAAα1, receptors in mPFC was determined by Western blot. Results Compared with C and S groups, thermal and mechanical pain threshold were significantly decreased and the expression of GABAAα1, receptors was up-regulated in group P ( P ＜ 0.01) . There was no significant difference was in the thermal and mechanical pain threshold and expression of GABAAα1 receptors between C and S groups (P ＞ 0.05). Conclusion Up-regulation of GABAAα1 receptor expression in mPFC may be involved in the development and maintenance of neuropathic pain in rats.