Biomedical subjects

Zhong-qi Liu

Publications and source records attributed to Zhong-qi Liu.

6 recordsLinked to original sources

PubMed2005

Expression of NASG gene and its role in human nasopharyngeal homogenous tissue cells.

BACKGROUND: The NASG gene has been confirmed as a tumor-suppressor gene candidate related to nasopharyngeal carcinoma (NPC) by previous studies. We further investigated the expression and the role of NASG in the homogeneous tissue cells by microdissecting the samples of tissue from human NPC, and introduced a new way to study the expression of specific genes in tumor tissue. METHODS: The RNAlater reagent was used to preserve the samples of tissue from the nasopharynx of NPC patients. The samples were microdissected to harvest the homogeneous tissue cells and then total RNA was isolated from them. The antisense RNA (aRNA) was amplified from the total RNA by "in vitro transcription (IVT)". We investigated NASG expression in the homogeneous tumor cells of NPC (22 samples) and compared it with that in the pure epithelial pillar cells of normal nasopharyngeal (10 samples) by semi-quantitative reverse transcription-polymerase chain reaction (sqRT-PCR). RESULTS: The high quality total RNA could be harvested from the microdissected homogeneous tissue cells of the nasopharynx, then sufficient aRNA was derived from it. NASG gene expression was identified using aRNA by sqRT-PCR and showed that there was significant difference between the average value of case groups and that of control group (t = -5.275, df = 30, P < 0.001). The NASG gene in the subgroups WHOII tended to express lower levels than those in the subgroup WHOIII although this difference was not statistically significant (t = -1.584, df = 20, P = 0.129 > 0.05). CONCLUSIONS: Microdissection was an effective method to obtain the homogeneous tissue cells of nasopharyngeal tissue (including the samples of NPC and non-NPC) in our study. Sufficient aRNA from amplifying total RNA could be used in sqRT-PCR to analyse the expression of NASG in the pure tissue cells. NASG should be a tumor-suppression gene candidate regarding to NPC.

Adult↗

PubMed2005

[Preliminary biomarker related to nasopharyngeal carcinoma filtered from the whole genome expression profiling involved in microdissection nasopharyngeal tissues].

OBJECTIVE: To filter biomarkers of nasopharyngeal carcinoma (NPC) by constructing the homogenesis tissue gene expression profiling with the whole human genome GeneChip. METHODS: The epithelium cells of the homogenesis NPC and the pure nasopharyngeal normal tissues microdissected from nasopharyngeal biopsy which was preserved in the RNAlater were used to isolate RNA and then to harvest the aRNA through in vitro transcription, and aRNA prober was labled to hybridize to HG-U133. plus 2.0, so the expression profiling of each homogenesis tissue could be constructed. RESULTS: Some candidate biomarker genes related to the tumorigenesis of NPC had been filtered by comparing the expression profiling of NPC samples with the expression profiling of normal nasopharyngeal epithelia samples. Any genes regarding the metastasis of NPC might have been selected by comparing the expression profiling of no-metastasis samples with those of the metastasis samples. CONCLUSION: Using the whole genome GeneChip to construct the expression profiling for the microdissected homogenesis tissue is effective to filter the candidate biomarker genes.

Adult↗

PubMed2005

[Experimental study of pilots' scan and performance, workloads].

OBJECTIVE: To study the problems of pilots' scan, performance, workload. METHOD: An experimental system for evaluating pilots' scan, performance, workload was built up based on previous studies. RESULT: After theoretical consideration and analysis of experimental results, the difference between expert pilots and novice pilots were disclosed preliminarily. CONCLUSION: Expert pilots demonstrates more frequent fixations with shorter dwell time than novice pilots do; to both pilots, the conclusion can be drawn that the variation between workloads and performance is not fixed.

Aerospace Medicine↗

PubMed2004

[Effect of drinking water change upon the dental fluorosis].

OBJECTIVE: To assess changes in prevalence and degree of dental fluorosis in individuals born before and after the introduction of water with 1.2 mg/L fluoride instead of water with 2.0-10.0 mg/L fluoride previously used in Da Li County in China. METHODS: The students (n = 291) were divided into 2 groups. The dental fluorosis was scored according to Dean's classification. The statistical analysis was performed by t-test and chi(2) tests. RESULTS: The prevalence of dental fluorosis was significantly lower in the group of the students drinking water from the new well (group 1) as compared to the group of the students drinking the old water (group 2), i.e. 48.8% versus 87.2% (P < 0.01). The percentage of moderate to very severe fluorosis was 13.9% and 0 in group 1 as compared to 32.0% and 8.8% in group 2. The fluorosis community index (FCI), defined by Dean, in group 1 and 2 was medium (1.01) and marked (2.12) respectively. CONCLUSIONS: The results showed that: (1) The prevalence of dental fluorosis was significantly lowered by the new source of drinking water. (2) Drinking water, even with 1.2 mg/L fluoride, may cause dental fluorosis during the period of tooth mineralization.

Adolescent↗

PubMed2002

Characteristics of eye movement and cognition during simulated landing of aircraft.

Objective. To examine how the subject scans different parts of display panels and how the attention is distributed through the analysis of the eye movement principle and the cognition of the brain. Method. An experiment was conducted to simulate the airplane's landing course and eye movement data were recorded with eye movement measure system (EMMS). Result. There were three regions of interest (ROI) on which the subject's attention was concentrated. The subject's visual activity was active in the three ROIS and attention's shifting and distribution was between ROIS. Conclusion. Eye movement were driven by the top-down processing and the distribution of the attention. The consequence of the eye movement makes the subject maintain a continuous situation awareness.

Aircraft↗

PubMed2002

Analysis of human two-dimension target-aiming movement.

Objective. To study the problem of human movement characteristics of target-aiming movement. Method. The authors first analyzed the essentials of target-aiming movement on the basis of previous research results, then designed and made a two-dimension experiment of target-aiming movement. Result. After theoretical consideration and analysis of experimental results, a new model of human two-dimension target-aiming movement was proposed, and the coefficients are determined experimentally. Conclusion. The model was verified by experimental data. It was demonstrated that the new model has an excellent suitability, and is applicable for evaluations of target-aiming movements of one and two dimensions.

Adult↗