[Forensic Application of Objective Assessment on Visual Acuity by ERP].

OBJECTIVES: To explore the composition characteristic of event related potential （ERP） in different visual acuity levels, and to provide theoretical basis for the objective assessment of visual acuity. METHODS: Monocular stimulus was performed on 16 selected subjects. The subjects were required to look straight at the screen ahead and count the amount of stimuli from different directions. The pictures of optotype stimulus which corresponding to three different visual acuity levels were showed in the center of the screen. The ERP results were recorded separately. RESULTS: （1） The P1 amplitudes of match stimuli recorded under the supra-threshold visual acuity level were higher than that of match stimuli recorded under the threshold and sub-threshold visual acuity levels. There was no significant difference between the P1 amplitudes of match stimuli recorded under the threshold and sub-threshold visual acuity levels. The tendency of conflict stimuli was similar to that of match stimuli under three visual acuity levels. （2） In the 340-500 ms post-stimulus range, P300 component was found under supra-threshold and threshold visual acuity levels; no P300 component was found in corresponding time window under sub-threshold visual acuity. The differences of P300 amplitudes among three visual acuity levels were statistically significant. The amplitudes from high to low were the supra-threshold, threshold and sub-threshold visual acuity levels. CONCLUSIONS: ERP can be a potential new method for the objective assessment of visual acuity in forensic medicine.

[Effect of Different Attentional Conditions on ERP Detection of Visual Acuity].

OBJECTIVES: To study the effect of different attentional conditions on the event-related potential （ERP） components generated by the visual information stimuli related to visual acuity, and provide a theoretical reference for clinical forensic visual objective evaluation. METHODS: With visual acuity optotypes as normal form of visual information stimuli, 15 volunteers as study subjects were supposed to account the visual acuity optotypes under the attentional condition of visual stimuli. Furthermore, the subjects were required to listen to the storytelling carefully under the non-attentional condition of visual stimuli, and after the examination, they needed to answer the story-related questions. All the EEG results of two different attentional conditions from the subjects were recorded by 32 channel ERP system. RESULTS: Under two attentional conditions, P1 and P300 components were evoked by the visual acuity optotypes on supra-threshold and threshold visual acuity levels, while only P1 component were evoked by the visual acuity optotypes on sub-threshold levels. In the ERP waveforms evoked by the visual acuity optotypes on supra-threshold, P1 and P300 amplitudes under attentional condition were larger than that under non-attentional condition. CONCLUSIONS: Attentional conditions can influence the detection of visual acuity. P300 component can be used to distinguish the visual acuity levels with supra-threshold and sub-threshold under non-attentional condition.

Expression of miR-210 in senile COPD complicating primary lung cancer.

OBJECTIVE: To analyze the expression and clinical significance of miR-210 in patients with senile chronic obstructive pulmonary disease (COPD) complicating primary lung cancer. 30 cases of COPD PATIENTS AND METHODS: 30 cases of primary lung cancer and 30 cases of COPD complicating lung cancer were selected. MiR-210 can function as the cancer suppressor gene in progress from COPD to primary lung cancer and may be used as an important auxiliary diagnosis index. Analysis of correlations between MiR-210 expression with clinical features such as age, sex, disease type, COPD disease classification, pathological pattern of neoplasia and TNM staging. RESULTS: The expression of miR-210 of COPD Group was significantly higher than the Lung Cancer Group. The level of COPD Complicating Lung Cancer was the lowest (p < 0.05). There was no remarkable difference among sex, age, smoking status, hypertension, diabetes mellitus and pathological type in each group (p > 0.05). Expression of miR-210 was lower with the aggravation of COPD and an increase of TNM staging (p < 0.05). CONCLUSIONS: MiR-210 expression level in the diagnosis of COPD complicating lung cancer had the sensitivity of 76.8%, specificity of 72.3%, accuracy of 0.73, 95% CI of 0.63-0.85 and critical value of 0.1825.

High-performance liquid chromatographic analysis with fluorescence detection of ethyl centralite and 2,4- dinitrotoluene in gunshot residues after derivatization with 9-fluorenylmethylchloroformate.

A reversed-phase high-performance liquid chromatographic method using 9-fluorenylmethylchloroformate (FMOC) as fluorogenic labeling reagent for the detection of ethyl centralite (EC) and 2,4-dinitrotoluene (2,4-DNT) in gunshot residues is reported. Residues were sampled with cotton wool swabs which were then extracted and the extracts cleaned by TLC. The sample spots on the TLC plate were scraped off and extracted to recover the analytes. The extract corresponding to EC was hydrolyzed while 2,4-DNT was reduced. The hydrolysis and reduction products (N-ethylaniline and 2,4-diaminotoluene, respectively) were derivatized with FMOC in alkaline buffer solution at 52 degrees C for 20 min. The derivatives were analyzed by a reversed-phase HPLC with fluorescence detection. The detection limits for EC and 2,4-DNT were 200 pg and 1 ng per standard sample, respectively. Three out of eleven kinds of gunpowders analyzed were found to contain EC, while another three were found to contain 2,4-DNT. According to the results of gunpowder analysis, two different kinds of ammunition, which were presumed to contain EC in one and 2,4-DNT in the other, were chosen for test firings. Ethyl centralite was detected in cotton swabs sampled from spent cartridge cases of both of these two kinds of ammunition, but 2,4-DNT was not detected in any of these spent cases. Nine out of twelve samples swabbed from shooting hands at various times after firing two rounds of either kind of ammunition were found to contain EC, while none of these swabs were found to contain 2,4-DNT. The quantities of EC recovered from these hand swabs were shown to be in the range of 0.6 to 4.0 ng.