Evaluation of Visual Acuity of Ametropia with Visual Event-Related Potential Nogo-P3 Component.

OBJECTIVES: To analyze the Nogo-P3 component of event-related potential (ERP) in the process of visual acuity processing, to provide electrophysiological evidence for objective evaluation of visual acuity. METHODS: Twenty-six subjects with no other ocular diseases except for ametropia were recruited, and all subjects had uncorrected visual acuity both eyes 1/10 (evaluated using Monoyer chart). Block letter E with different visual angles and directions were used as graphic stimuli. The Go/Nogo paradigm was used for ERP studies. The visual angle of Go stimulation angle was 1°15', Nogo stimuli were 1°15', 55', 24' and 15'. The visual acuity test was performed on each of the two naked eyes separately in all subjects, and the characteristics of the Nogo-P3 component were analyzed. RESULTS: The latency of Nogo-P3 showed no difference between the stimuli of 1°15' and 55', and between Nogo stimulation angle 24' and 15'. There was significant difference between Nogo stimulation angle 1°15' and 24', and between Nogo stimulation angle 1°15' and 15' (P<0.05). There was significant difference between Nogo stimulation angle 55' and 24', and between Nogo stimulation angle 55' and 15' (P<0.05). No significant differences were observed in the Nogo-P3 amplitude among Nogo stimulation. CONCLUSIONS: In the Go/Nogo paradigm, Nogo-P3 can reflect the cognitive response of subjects to Nogo stimulation, which can be used for objective evaluation of visual acuity.

Comparison of ASSR, ABR and 40 Hz AERP Response Thresholds at Different Frequencies and Their Forensic Applications.

OBJECTIVES: To explore the relationship between the frequency characteristics and response threshold of auditory steady-state response (ASSR), auditory brainstem response (ABR) and 40 Hz auditory event related potential (40 Hz AERP), and their application values in forensic medicine. METHODS: Thirty volunteers with normal hearing (60 ears) were selected to perform pure tone audiometry (PTA) threshold and ASSR, ABR and 40 Hz AERP response threshold tests in the standard sound insulation shielding room, and the results were statistically analyzed by SPSS 22.0 software. RESULTS: At 0.5 kHz and 1.0 kHz frequencies, the correlation between 40 Hz AERP response threshold and PTA threshold was good, which was better than that of ASSR and ABR response threshold. At 2.0 kHz and 4.0 kHz frequencies, the correlation between ASSR and ABR response thresholds and PTA threshold was good, which was better than that of 40 Hz AERP response threshold. CONCLUSIONS: To evaluate the hearing at 0.5 kHz and 1.0 kHz frequencies, it is recommended to use 40 Hz AERP and ASSR to comprehensively assess the PTA threshold of the subjects. To evaluate the hearing at 2.0 kHz and 4.0 kHz frequencies, ABR and ASSR are recommended to assess the PTA threshold of subjects comprehensively. The combination of ASSR, ABR and 40 Hz AERP can improve the accuracy of hearing function evaluation.

[Advances in Event-related Potential and Its Forensic Application Value].

The event-related potential (ERP) is considered as one of the most effective methods to study and analyze objectively human mental activity based on nerve electrophysiology. At present, ERP is not only used in the study of lie detection, but also in the clinical medicine for the cognitive assessment on patients with cerebrovascular disease, dementia or traumatic brain injury and auxiliary diagnosis of mental illness. With the further development of ERP detection technology, it would have a wider application prospect in the field of forensic medicine.

Aliifodinibius roseus gen. nov., sp. nov., and Aliifodinibius sediminis sp. nov., two moderately halophilic bacteria isolated from salt mine samples.

Two rod-shaped, non-motile bacteria were isolated from two separate salt mines in Yunnan, south-western China. These strains, designated YIM D15(T) and YIM J21(T), were Gram-negative and moderately halophilic. The two strains required 6-10 % NaCl (w/v; optimal) for growth. The DNA G+C contents of strains YIM D15(T) and YIM J21(T) were 49.0 mol% and 48.4 mol%, respectively. The predominant isoprenoid quinone was MK-7. The polar lipid profiles of strains YIM D15(T) and YIM J21(T) were composed predominantly of diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, three unknown polar lipids and one glycolipid. Minor amounts of other lipids were also detectable. The predominant cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C17 : 1ω9c/10 methyl-C16 : 0 and C16 : 1ω7c/C16 : 1ω6c. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed that the two isolates formed a distinct clade with the genus Fodinibius (in the phylum Bacteroidetes) and were related to the species Fodinibius salinus, with sequence similarities of 91.9-92.4 %. Analyses of 16S rRNA gene sequences revealed that strains YIM D15(T) and YIM J21(T) were related to each other (97.3 % sequence similarity). The DNA-DNA hybridization relatedness between the two isolates was 34 %. On the basis of the phylogenetic analysis, DNA-DNA hybridization relatedness, phenotypic and chemotaxonomic characteristics, strains YIM D15(T) and YIM J21(T) should be classified as members of a novel genus and as two novel species, for which the names Aliifodinibius roseus gen. nov., sp. nov. (type strain YIM D15(T) = ACCC 10715(T) = KCTC 23442(T)) and Aliifodinibius sediminis sp. nov. (type strain YIM J21(T) = ACCC 10714(T) = DSM 21194(T)) are proposed.

Gracilimonas mengyeensis sp. nov., a moderately halophilic bacterium isolated from a salt mine in Yunnan, south-western China.

A facultatively anaerobic, Gram-staining-negative, pale red-pigmented, non-motile, rod-shaped, moderately halophilic bacterium, designated strain YIM J14(T), was isolated from a sediment sample from a salt mine in Yunnan, south-western China. Growth occurred at NaCl concentrations of between 2 % and 15 % (w/v) and optimally with 5-9 % NaCl. The optimum temperature and pH for growth of the strain were 28 °C and pH 7.5. The major cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0 and iso-C17 : 1ω9c/10-methyl-C16 : 0. The polar lipid profile was composed predominantly of diphosphatidylglycerol, phosphatidylcholine and one unknown phospholipid. Minor amounts of other lipids were also detectable. The genomic DNA G+C content was 47.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons indicated that strain YIM J14(T) was related to Gracilimonas tropica in the phylum Bacteroidetes. The level of 16S rRNA gene sequence similarity between strain YIM J14(T) and Gracilimonas tropica CL-CB462(T) was 96.9 %. A DNA-DNA hybridization experiment between strain YIM J14(T) and Gracilimonas tropica indicated levels of relatedness of 28 %. Chemotaxonomic data supported the placement of strain YIM J14(T) in the genus Gracilimonas. DNA-DNA hybridization and biochemical and physiological characterization allowed strain YIM J14(T) to be differentiated from Gracilimonas tropica. It is therefore considered to represent a novel species of the genus Gracilimonas, for which the name Gracilimonas mengyeensis sp. nov. is proposed. The type strain YIM J14(T) ( = ACCC 10717(T) = DSM 21985(T)).

Forensic Study on Objective Evaluation of Visual Acuity of Ametropia with the Event-related Potential P3.

OBJECTIVE: In this study, we aimed to assess the characteristics of the P3 component from an event-related potential (ERP) that was induced by visual acuity (VA) processing. Furthermore, we sought to provide electrophysiological evidence for the objective evaluation of VA. METHODS: We recruited 32 participants with myopia-related ametropia. They reported no other ocular diseases and had an uncorrected VA of 4.0 in both eyes. We used the block letter "E" at different visual angles and orientations as the graphic stimuli. The oddball paradigm, consisting of 4 modules, was used for ERP analysis. The standard stimuli of each module were identical, with a visual angle of 1°15'. The visual angles of the target stimuli were 1°15', 55', 24', and 15'. The VA test was performed on each eye separately for all participants, and all characteristics of the P3 component were analyzed. RESULTS: There was no significant difference in the P3 peak letencies between the target stimulation angle 1°15' group and the 55' group, or between the target stimulation angle 24' group and the 15' group. There was a significant difference in the P3 peak letencies between the target stimulation angle 1°15' group and the 24' group as well as the 15' group. There was a significant difference in the P3 peak letencies between the target stimulation angle 55' group and the 24' group as well as the 15' group. No significant differences were observed in the P3 amplitude between modules. CONCLUSION: In the oddball paradigm, P3 elicitation indicated a cognitive response to the target stimuli. These data showed that the characteristics of P3 can be used as an objective evaluation of VA.

Roseivivax sediminis sp. nov., a moderately halophilic bacterium isolated from salt mine sediment.

A Gram-negative, facultatively anaerobic, short rod-shaped, heterotrophic bacterium, designated strain YIM D21(T), was isolated from a salt mine in Yunnan province, south-west China. Strain YIM D21(T) formed cream-yellow colonies, was non-motile and moderately halophilic, and tolerated NaCl concentrations of 1-15% (w/v), with optimum growth at 5-10 % (w/v). Growth occurred at 15-42 °C (optimum 28 °C) and at pH 6.5-8.5 (optimum 7.5-8.0). The respiratory quinone was ubiquinone-10 (Q-10). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, three unidentified phospholipids, one unidentified aminolipid and two unidentified lipids. The major fatty acids were C(18:1)ω7c and cyclo C(19:0)ω8c and the DNA G+C content was 67.7 mol%. Phylogenetic analyses revealed that strain YIM D21(T) belongs to the genus Roseivivax. 16S rRNA gene sequence similarities of YIM D21(T) were 95.7, 95.0 and 94.8% with the type strains of Roseivivax halodurans, Roseivivax lentus and Roseivivax halotolerans, respectively. Physiological and biochemical tests allowed phenotypic differentiation of strain YIM D21(T) from closely related species with validly published names. We therefore propose that this isolate represents a novel species, Roseivivax sediminis sp. nov.; the type strain is YIM D21(T) ( = KCTC 23444(T) = ACCC 10710(T)).

Fodinibius salinus gen. nov., sp. nov., a moderately halophilic bacterium isolated from a salt mine.

A novel, moderately halophilic, rod-shaped bacterium, designated strain YIM D17(T), was isolated from a sample of sediment from a salt mine in Yunnan, south-western China. The taxonomy of strain YIM D17(T) was investigated using a polyphasic approach. Strain YIM D17(T) was Gram-stain-negative, strictly aerobic and non-motile and formed pink colonies on marine agar. Optimal growth occurred at 37 °C, pH 7.5-8.0 and in the presence of 10-15 % (w/v) NaCl. The major menaquinone was MK-7. The polar lipid profile was composed predominantly of diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, one phospholipid, one glycolipid and one aminolipid. Minor amounts of other lipids were also detectable. The predominant cellular fatty acids were iso-C(17 : 1)ω9c/10-methyl-C(16 : 0) (24.0 %), iso-C(15 : 0) (23.6 %) and C(16 : 1)ω7c/C(16 : 1)ω6c (13.8 %). The DNA G+C content was 43.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed that the isolate formed a distinct clade with the genera Gracilimonas and Balneola (both in the phylum Bacteroidetes) and was related to the species Gracilimonas tropica, Balneola vulgaris and Balneola alkaliphila, with sequence similarities of 85.6 %, 83.0 % and 82.8 % to the respective type strains. On the basis of its phenotypic, chemotaxonomic and phylogenetic features, strain YIM D17(T) represents a novel species of a new genus, for which the name Fodinibius salinus gen. nov., sp. nov. is proposed. The type strain is YIM D17(T) ( = ACCC 10716(T) = DSM 21935(T)).

[Analysis of forensic identification of traumatic macular hole in 16 cases].

OBJECTIVE: To analyze and summarize the characteristics of traumatic macular hole and to discuss the key points and matters need attention in forensic identification. METHODS: Sixteen cases of traumatic macular hole were collected from Forensic Science Identification Center of China Medical University from 2004 to 2009 and analyzed. RESULTS: All of the 16 cases resulted from closed ocular contusion. Traumatic macular hole was more common in young men and may occur immediately after injury or after a certain interval. Six months after injury, there was a spontaneous closure of macular hole in 2 cases and the vision of the injured in 12 cases improved to different degrees. According to the degree of vision dysfunction, 12 cases were identified as slight injury, 4 cases were identified as severe injury. CONCLUSION: Traumatic macular hole has its characteristics. Its injury degree is all slight or severe injury. The time of identification should be within 3-6 months.

[Analysis of 158 forensic identification cases involved with peripheral nerve injury].

OBJECTIVE: To study the characteristics of forensic identification cases involved with peripheral nerve injury, and to discuss how to apply the clinical information, forensic examination and neurophysiological testing. METHODS: One hundred and fifty-eight cases which were diagnosed peripheral nerve injury in clinic, were collected. Then the individual characteristics, injuries, identification results, exaggeration or camouflage were analysed. RESULTS: The male, the unemployed, and the young and middle-aged were common in our cases. The main reasons of "peripheral nerve injury" were traffic accidents and sharp injuries. Most wounded parts were in limbs. Also the exaggeration and camouflage accounted for a considerable proportion in our cases. CONCLUSION: The forensic identification of "peripheral nerve injury" cases should be evaluated with clinical information, forensic examination and electrophysiological testing comprehensively.

[Application of spiral CT reconstruction in the forensic identification of atlantoaxial injuries].

OBJECTIVE: To evaluate diagnostic value of spiral CT reconstruction in atlantoaxial injuries. METHODS: The images of 25 cases of spiral CT reconstruction were analyzed and compared with images of CT scan and X-ray. RESULTS: In 7 cases of odontoid process fracture, X-ray demonstrated 4 cases and CT demonstrated 5 cases, whereas the spiral CT reconstruction diagnosed 7 cases, which could display the displacement of fracture clearly. The X-ray and CT showed asymmetric space between left and right gaps of atlantoaxial joint in 6 cases, while spiral CT reconstruction showed normal and excluded the possibility of atlantoaxial dislocation. There was one case of lateral atlantoaxial joint dislocation, which was demonstrated by the spiral CT reconstruction clearly but not by the X-ray and CT scan. There were 3 cases of atlantoaxial congenital deformity (1 case of absence of both posterior arch of atlas and odontoid process and 2 cases of maldevelopment of the odontoid process), which were displayed clearly by spiral CT reconstruction, but misdiagnosed as odontoid process fracture and atlantoaxial subluxation by X-ray and CT scan. CONCLUSION: Spiral CT reconstruction can provide the most accurate and integrity imaging information and is very useful in the diagnosis of atlantoaxial injuries and deformity.

[The PRVEPs evoked by different fields stimulation].

OBJECTIVE: To study the character of the PRVEPs evoked by different stimulation fields in normal-vision subjects and its value in forensic medicine. METHODS: The PRVEPs were evoked by full-field, central-field and peripheral-field respectively in 30 subjects (60 eyes) and the latency and amplitude of N1 and P1 were analyzed. RESULTS: There was no statistically significant difference in the latency and amplitude of PRVEPs between right and left eyes. The appearance probability of all the waves was 100% at the different stimulations but that of N1 was 36.77% at the central-field. There was statistically significant difference in the latency of N1 at the full field and peripheral field stimulations and there was no statistically significant difference in the amplitude. There was statistically significant difference in the latency and amplitude of P1 at the full field, central field and peripheral field stimulation. CONCLUSION: The PRVEPs evoked by different field stimulations can be used to evaluate the functions of the different area retina and can be used to identify the exaggerated or pretended visual dysfunction.

[Auditory P300 in the patients with traumatic brain injury].

OBJECTIVE: To assess the cognitive dysfunction in patients with the traumatic brain injury (TBI) by auditory P300. METHODS: Auditory P300 was recorded in the normal subjects and patients with TBI at the active (foot pedal) and passive task. RESULTS: In healthy persons, N2 and P3 in active task state showed higher amplitude than that in passive task state, and no significant prolongation of the latency. The amplitude of N1 and P2 at Cz was higher than that at Pz. In passive task state, N2 and P3 showed higher amplitude and longer latency in the patients than that in the healthy persons. N2 and P3 of the patients in the active task showed higher amplitude and longer latency than that in the passive task. Obvious change of P3 latency was observed in the patients with attention disorder. CONCLUSION: The type of task mainly affect the amplitude of N2 and P3. The latency of N2 and P3 in passive task can be used as an indication for evaluating cognitive function in patients with diffuse brain injury.

Halomonas sediminis sp. nov., a new halophilic bacterium isolated from salt-lake sediment in China.

A novel Gram-negative, slightly halophilic, catalase- and oxidase-positive, obligately aerobic bacterium, strain YIM-C248(T), was isolated from a sediment sample collected from a salt-lake in the Qaidam Basin in Qinghai, north-west China. Cells were non-sporulating short rods, occurring singly or as doublets, motile with peritrichous flagella. Growth occurred with 1-15% (w/v) NaCl [optimum 2-4% (w/v) NaCl], at pH 6.0-10.0 (optimum pH 7.5) and at 4-35 degrees C (optimum 25-30 degrees C). The major cellular fatty acids were C(18:1) omega 7c, C(12:0) 3-OH, cyclo C(19:0) omega 8c, C(16:0) and C(16:1). The predominant respiratory quinone was Q-9 and the genomic DNA G + C content was 58.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YIM-C248(T) should be assigned to the genus Halomonas. The sequence similarities between the isolate and the type strains of members of the genus Halomonas were in the range of 92.5-97.5%. The combination of phylogenetic analysis, DNA-DNA hybridization data, phenotypic characteristics and chemotaxonomic differences supported the view that strain YIM-C248(T) represents a new species of the genus Halomonas, for which the name Halomonas sediminis sp. nov. is proposed, with YIM-C248(T) (=CCTCC AA 207031 = KCTC 22167) as the type strain.

[Electrophysiological examination of peripheral nerve injury and its significance in forensic medicine].

Assessment of peripheral nerve injury is a common task in forensic practice. As an objective assistance of inspection, electrophysiological examination is significant in the evaluation of peripheral nerve function after injury. There are currently several methods of electrophysiological examination, including I-T curve, EMG, NCV and SEP. Because electrophysiological examination can assess the injury and regeneration of peripheral nerve injury at different times, it is valuable to estimate prognosis of peripheral nerve injury in forensic medicine. Besides the electrophysiological examination, evaluation of the peripheral nerve injury needs to combine other clinical manifestations to provide an accurate appraisal.

[Advancement in the study on electrophysiology of color vision and its applicability in forensic medicine].

Color vision is a major component of vision function. Examination of color vision mostly relies on subjectivity at present. It is important to establish an objective method of color vision examination that would have particular clinical significance and forensic medicine value. With the development of new technology, the examination of visual electrophysiology has become a basic method of clinical diagnosis and investigation. Electroretinogram (ERG) could discriminate different cone cells and color abnormality. Visual evoked potential (VEP) generated characteristic negative wave after stimulation with different colors. Different visual electrophysiology detection methods were reviewed and in particular important new advancement of color vision research of ERG, F-VEP and P-VEP were introduced. The application prospect of color vision research in the clinical forensic medicine was also discussed. It is likely that color vision research study and visual electrophysiology will provide objective evaluation of retina and brain function.

Characteristics of Pattern Visual Evoked Potential in Two Eyes with Varying Visual Acuity in One Eye and Forensic Application.

In this study, we aimed to study the pattern visual evoked potentials (P-VEPs) in two eyes with varying visual acuity in one eye and to provide an objective estimation of visual acuity by comparing P-VEPs in one and two eyes. Thirty subjects were chosen, who had one eye with an acuity of 5.0, 4.85, 4.6, 4.0, or scieropia and obstructed vision and the other eye with an acuity of 5.0, respectively. P-VEPs were detected under the large grating stimuli at 3×4 spatial frequency, moderate grating stimuli (12×16 spatial frequency) and small grating stimuli (48×64 spatial frequency). Under large grating stimuli, there was no significant difference in P100 peak latency between the groups, nor was there a significant difference between the amplitude of two eyes and the amplitude of one normal-vision eye. Under moderate and small grating stimuli, there was a significant difference in P100 peak latency between the group with both eyes having an acuity of 5.0 and the group with visual acuity below 4.0 in one eye. There was a significant difference in P100 amplitude between the group with visual acuity of 5.0 in both eyes and the group with one normal-vision eye. There was no significant difference in the amplitude of two eyes and the amplitude of one normal-vision eye between any other two groups. In forensic identification, characteristics and variability of P-VEPs in one and two eyes can be used to identify malingering or decline in visual acuity.

[Prokaryotic microbial diversity of the ancient salt deposits in the Kunming Salt Mine, P.R. China].

The prokaryotic microbial diversity of the ancient salt deposits in the Kunming Salt Mine, PR China was investigated using PCR-DGGE and rRNA approaches. Total community DNA was extracted and purified by a direct method, which yielded amplified DNA of high molecular weight for samples. A variable region of 16S rRNA gene was then amplified by PCR with bacterial and archaeal primers and analyzed by denaturing gradient gel electrophoresis (DGGE). Twenty-seven major bands were detected in the bacterial DGGE profile of the sample, but only one band of pure culture strains of bacteria isolated from the Kunming Salt Mine matched with one band of sample. No band of pure culture strains of archaea isolated from the Kunming Salt Mine matched with 18 major bands of sample. The results indicated that most of microbes in this environment are likely uncultivable. Clones on the plate were not the predominant species in the community. Two 16S rRNA gene clone libraries (bacteria and archaea) were also constructed, and 36 and 20 clones were selected for amplified ribosomal DNA restriction analysis (ARDRA). ARDRA with enzymes Afa I, Hha I, Hae III revealed 10 bacterial operational taxonomic units (OTUs), with three most abundant OTUs accounting for 38.9%, 25.0%, 16.7% of all the bacterial 16S rDNA clones, respectively. The remaining 7 OTUs presented at low levels, were represented by a single clone. Eight archaeal OTUs were obtained but no predominant OTUs. Some clones were sequenced and each sequence was compared with all nucleotide sequences in GenBank database. Examination of 16S rDNA clones showed that the ancient salt deposits in the Kunming Salt Mine contained a phylogenetically diverse population of organisms from the Bacteria domain with members of three major lineages represented: alpha-proteobacteria, gamma-Proteobacteria and Actinobacteria, especially Pseudomonas. Surprisingly, we recovered a variety of sequence closely related to Actinobacteria which was not found in other salt deposits. All of archaeal clones are from Halorubrum, Haloterrigena and uncultured archaea. The results of DGGE and clone library profiling analysis both indicated that microbial community of the Kunming Salt Mine had higher diversity. In this initial survey, our polyphasic approaches demonstrated that novel and uncultured microbes thrive in the ancient salt deposits of the Kunming Salt Mine. Molecular analysis of the microbial diversity in salt deposits provides foundation for better application of microbial resources.

[Abortion etiologies and their forensic identification].

The causes of abortion are complicated and variable. Genetic abnormalities, immune disorders, endocrine disorders, and sperm abnormalities are the most common etiologies. Other risk factors include infections, genital malformation and diseases, systemic diseases, environmental factors, psychiatric problems, fections, genital malformation and diseases, systemic diseases, environmental factors, psychiatric problems, surgery, and maternal trauma. In forensic assessment of abortion and its etiology, trauma-induced abortion can only be determined after exclusion of all other non-traumatic causes.

[The retrospective analysis of 23 cases of post-traumatic abortion].

OBJECTIVE: To analyze the clinical characteristics of post-traumatic abortion and the relationship between trauma and abortion. METHODS: We collected and analyzed 23 cases of post-traumatic abortion encountered in the department of clinical forensic medicine, faculty of forensic medicine, China Medical University in recent years. RESULTS: All 23 post-traumatic abort inns were early abortions. Their traumata were mild and external only. Vagina bleeding and abortion occurred shortly after trauma. Most patients were older, from countryside, or unemployed. CONCLUSION: The causes of abortion are complex. Post-traumatic abortion can only be diagnosed after excluding non-traumatic factors. For those cases abortion occur shortly after injuries and non-traumatic factors can not be excluded, trauma should be assessed for its role in abortions as primary, secondary or induction factors correlated with clinical symptoms and pre-