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Biomedical subjects

G Liu

Publications and source records attributed to G Liu.

At least 163 records · Page 9Linked to original sources
PubMed2001

[Correlation between nutrient levels of vitamin A and zinc and HOX C4 gene expression in mice embryos].

OBJECTIVE: Correlation between nutrient levels of vitamin A and zinc and HOX C4 (3.5) gene expression in mice embryos was studied. METHODS: The Kunming female mice were divided three groups: deficient group (DG) fed with fodder deficient of vitamin A and zinc, replenished group (RG) fed with fodder deficient of vitamin A and zinc until the 7th day after conception and then fed with fodder rich in vitamin A and zinc, and normal group (NG), fed with normal fodder. After obvious symptoms of vitamin A and zinc deficiency appeared, the mice were mated. On the 12th day after conception, pregnant mice were killed and their levels of vitamin A and zinc were determined and the content of mRNA of HOX C4 (3.5) were determined for the embryos with situ hybridization. RESULTS: The level of vitamin A was 0.44 mumol/L, 1.03 mumol/L and 1.40 mumol/L, respectively and that of zinc 124.3 mg/kg, 152.1 mg/kg and 193.8 mg/kg in DG, RG and NG, respectively. The mRNA of HOX C4 (3.5) gene expression in mouse embryos increased significantly in DG, RG and NG (P < 0.05). CONCLUSIONS: Levels of vitamin A and zinc in the body of pregnant mice positively correlated significantly with their HOX C4 (3.5) gene expression, with coefficients of correlation of 0.78 to 0.99.

Animal Nutritional Physiological Phenomena↗
PubMed2001

[Study on the epidemiological feature and control measure for rabies from 1990 to 2000 in Jiangsu province].

OBJECTIVE: To analyze the epidemiological feature of rabies and explore the risk factors in Jiangsu for the control of rabies. METHODS: Data on rabies in Jiangsu from Jan. 1990 to Sep. 2000, and on case studies as well as surveillance from 1998 to 2000, were collected. Circular distribution statistics and Chi-square test were used. RESULTS: The number of rabies had been decreasing since 1990 yearly, but increased in the last two years. The new cases of rabies tended to focus in the area of Nantong, Yanchen and Taizhou city. There were about 80% of cases in the above areas. Dogs were the main hosts (93.22%). Ninety-four point nine two percent of the persons were affected through dog bites with major wounded part as thoracic limbs (46.27%). Rates of severe bites, being wounded close to the central nervous system and more than 1 wound per cases were significantly higher than that in the population under surveillance. The antibody conversion rate was 86.28% after immunization in the surveillance population. The immunization rate was 58.20% among dogs. CONCLUSION: Severe deep bites, wounded part close to the central nervous system and more than 1 wound per case were the risk factors in patients with rabies. Maltreatment and low immunization rate were important risk factors as well.

Animals↗
PubMed2001

[Current status and distribution of deafness in the elderly in several cities in China].

OBJECTIVE: To survey the current status and distribution of deafness and its effect on daily life activities in the old population. METHODS: Eight thousand two hundred and fifty-two elderly aged 60 years and above in the urban and rural areas of Beijing, Shanghai, Guangzhou, Chengdu, Xi'an and Shenyang were investigated, using a clustered random sampling methods. RESULTS: Overall crude prevalence of deafness in the elderly was found to be 33.7%, but the self-reported crude prevalence was low, only 47.1% when shown by medical examination. Crude prevalence rates were increasing with ageing, with 21.6%, 30.0%, 35.6%, 42.6%, 55.5% and 61.6% respectively (P < 0.01) in the age groups of 60-, 65-, 70-, 75-, 80-, 85- years old. Rate of deafness was highest in Beijing (58.5%), among the in-house workers (48.9%) and the lowest in scientists, teacher and health workers (28.5%). Logistic regression analysis showed that the crude prevalence was related to ageing, profession and area (P respective < 0.01). CONCLUSION: The prevalence of deafness was high in the elderly which increased with ageing with different areas, professions and the level of education. It was lower when self-reported than shown by medical examination. Prevention and treatment of deafness in the elderly should be strengthened.

Age Factors↗
PubMed2001

[Social economical status, behaviors and environment as the risk factors of tuberculosis in Chengdu China].

OBJECTIVE: To study the risk factors of pulmonary tuberculosis in Chengdu, Southwest China. METHODS: A population-based case-control study was used which included 174 cases selected from 12 communities in Chengdu and 174 controls selected from registered population with normal chest radiograph. Cases were active TB patients which were matched for age, sex with controls, then interviewed by trained interviewers using a standardized questionnaire. RESULTS: Social economic status measured by education, occupation and income did not show obvions influence to TB; It found that the active smoking, passive smoking, type of cigarettes and alcohol consumption had no significanct effects on TB during logistic regression analysis. The study showed that a person who was smoking and also alcohol intake had a higher risk to get TB (OR = 6.12, 95% CI = 1.15 - 32.49). Significant association was showed in the Dose-Response Analysis (OR = 1.37, 95% CI = 1.30 - 2.30). Crowded living space (OR = 1.14, 95% CI = 1.05 - 1.25), degree of darkness (OR = 2.18, 95% CI = 1.11 - 4.27) and moisture (OR = 4.06, 95% CI = 2.25 - 7.33), poor sanitary (OR = 3.03, 95% CI = 1.22 - 4.44), airpollution of working environment, which were filled with dusts (OR = 2.35, 95% CI = 1.18 - 4.70) and chemical fumes (OR = 5.15, 95% CI = 1.44 - 18.40) were strongly associated with pulmonary tuberculosis. BMI also had strong relationship with TB (OR = 4.72, 95% CI = 2.68 - 8.33). CONCLUSION: Poor environment and exposure to dust and chemical fume under working condition, low BMI, smoking combining alcohol consumption were the risk factors of adult pulmonary tuberculosis in Chengdu, China.

Adolescent↗
PubMed2001

[GATA-2 gene expression in leukemia patients and its significance].

OBJECTIVE: To investigate GATA-2 gene expression in leukemia patients and its clinical significance. METHODS: GATA-2 gene transcripts were detected by reverse transcriptase polymerase chain reaction (RT-PCR), and bcr/abl or PML/RAR alpha transcripts were detected in patients with chronic myeloid leukemia (CML) and acute promyelocytic leukemia (APL), respectively. RESULTS: The GATA-2 transcripts were revealed in 93% of acute myeloid leukemia (AML), in 70% of acute lymphoblastic leukemia (ALL), and 83% of CML patients, but not in normal bone marrow and peripheral blood cells. GATA-2 expression in remission patients was similar to newly diagnosed or relapsed patients. In post-transplantation patients, GATA-2 expression was significantly decreased. In these cases GATA-2 transcripts could be detected with bcr/abl fusion gene disappeared in 2 of 12 CML, whereas neither GATA-2 nor PML/RARalpha transcripts could be detected in APL. CONCLUSION: GATA-2 transcripts was highly expressed in leukemia patients and had no change in remission but significantly decreased in post-transplantation patients. Detection of GATA-2 expression would give information about the residual leukemia stem cells.

Bone Marrow Cells↗
PubMed2001

[Effect of head-down bed rest on human EEG].

Objective. To study the influences of short-term simulated weightlessness on human EEG. Method. EEG of 12 male subjects (aged 18-22) was recorded, pre-HDBR (-6 degrees head down bed rest), mid-HDBR (3rd, 4th, 6th day) and post-HDBR (3rd day). Then these EEG recordings were analyzed by power spectral analysis. Result. During HDBR, peak frequency of EEG gradually slowed down (6th day, P<0.05). Alpha-band activities were enhanced (alpha1: P<0.001. Alpha2: 3rd and 6th day, P<0.05; 4th day, P<0.001) and reached maximum on the 4th day. Alpha1/alpha2 ascended (6th day, C3 and C4: p<0.02; F4, P4, T3, T4, T5: P<0.05). Theta-band activities enhanced (P<0.001), and reached maximum on the 3rd day at frontal regions, on the 4th day at parieto-occipital regions. Theta/alpha ascended obviously (6th day, P3, O1: P<0.05). Meanwhile, beta1, activities also enhanced (P<0.001), and reached maximum on the 3rd day at frontal regions. After HDBR, the index that recovered to the pre-HDBR level first was EEG peak frequency. Conclusion. HDBR caused obvious changes of EEG power spectrum characteristic. There exists a potential influence on brain function.

Adolescent↗
PubMed2001

[Application of degree of complexity in heart rate variability analysis during orthostatic (correction of orthosatic) standing].

Objective. To introduce the degree of complexity in characterizing heart rate variability (HRV), and to discuss the changes in complexity of the cardiovascular system during orthostatic standing posture. Method. ECG of 8 subjects were recorded during supine and orthostatic standing postures. Degree of complexity was used to analyze the HRV. Result. Compared to supine before orthostatic standing posture, R-R intervals and its standard deviation at 0-5 min, 5-10 min, 10-15 min and 15-20 min during orthostatic standing posture were decreased significantly; the degree of complexity of HRV at 0-5 min and 15-20 min during orthostatic standing posture were decreased significantly; the approximate entropy of 0-5 min and 15-20 min were decreased significantly. Conclusion. The results showed that HRV and complexity of cardiovascular system was decreased during orthostatic standing. It was feasible that the degree of complexity can be used to analyze HRV.

Adolescent↗
PubMed2001

[Detection and partial nucleotide sequence analysis of hepatitis G virus in sera of patients with hepatitis in Guangzhou].

OBJECTIVE: To investigate hepatitis G virus (HGV) infection in hepatitis patients and the gene type of HGV in Guangzhou. METHODS: Reverse transcriptase-nested polymerase chain reaction(RT-nested PCR) method using primers locating in noncoding region of HGV genome was used for detecting HGV RNA in sera of hepatitis patients and the amplified products were directly sequenced. RESULTS: 25 cases were HGV RNA positive in 251 sera of acute and chronic hepatitis(9.96%), of which 4 cases were positive in 56 sera with hepatitis non A-E(7.14%), 8 cases were positive in 77 sera with hepatitis B (10.39%), 13 cases were positive in 118 sera with hepatitis C(11.17%). The identity of nucleotide sequence was 98.0% between 2 Guangzhou HGV isolates, both were 91.1% with American isolate, 81.7% and 84.2% respectively between 2 Guangzhou isolates and African isolate. CONCLUSION: HGV infection exists in hepatitis patients, 2 Guangzhou HGV isolates may belong to the same gene type and both of them have a high homology with American HGV isolate.

Base Sequence↗
PubMed2001

[Study of peak expiratory flow in normal young, middle-aged and old persons in Chengdu area].

OBJECTIVE: To build the normal ranges and regression equations of peak expiratory flow (PEF) in normal young, middle-aged and old persons. METHODS: PEF, FVC, V75, V50, V25 were measured in 393 normal young, middle-aged and old persons with the youngest aged 20 years and the eldest 84 years. Regression equations of PEF were built for younger group (20 yr-49 yr) and elder group (50 yr-84 yr) respectively. RESULTS: PEF, FVC, V75, V50, V25 were decreased with increase of age. The regression equations showed that both in younger and elder groups, PEF was negatively correlated with age in male (P < 0.0001-0.002, r = 0.32-0.39) and positively correlated with FVC in female (P < 0.0001-0.0005, r = 0.32-0.59). PEF was highly correlated to V75 with r = 0.87-0.94 in male and r = 0.93-0.96 in female. The coefficient of variation (CV) of PEF was in normal range (16%-24%) for all age groups except male and female above 70 years old with CV of 30% and 27% respectively. This confirmed the data was reliable. CONCLUSION: The normal ranges and regression equations of PEF constructed as a result of this study for normal humans of 20-84 years old can be put to use in clinical work and public health.

Adult↗
PubMed2001

[Study of peak expiratory flow in 728 normal adolescents in Chengdu area].

OBJECTIVE: This study was carried out to build the normal values and regression equations of peak expiratory flow (PEF) in normal adolescents. METHODS: PEF and routine ventilatory functions, FVC, V75, V50, V25 were measured in 728 normal adolescents aged 8-19. RESULTS: The PEF and FVC, V75, V50, V25 rose with the increase of age. The regression equations showed that PEF was highly positively correlated with age and FVC both in male and female adolescents, and also positively correlated with body weight in males; the coefficients of multiple correlation were 0.85 and 0.78 in male and female ones respectively. Correlations of PEF with V75, V50, V25 were also high, especially with V75 of which the correlation coefficients came up to 0.98 both in male and female adolescents. The coefficients of variation were 15%-20% both in male and female adolescents, and were in normal ranges. CONCLUSION: The normal ranges and regression equations of PEF provided for normal adolescents can be used to evaluate the pulmonary functions of patients who are in the same age-group suffering from bronchial asthma and other respiratory diseases.

Adolescent↗
PubMed2001

[The effects of MMPs and TIMPs on the metastasis of oral squamous cell carcinoma to neck lymph nodes].

OBJECTIVE: This study is aim at investigating the relationship between the expression and activity of MMP-2,9, TIMP-1,2 and the metastasis of oral squamous cell carcinoma to neck lymph node. METHODS: The expression of MMP-2,9, TIMP-1,2 in 30 oral squamous cell carcinoma, two oral squamous cell carcinoma cell lines GNM and TSCCa was detected by in situ hybridization; Zomography was performed to determined the activity of MMP-2,9 in cancer tissue and conditioned medium of GNM and TSCCa; Ability of invasion of GNM and TSCCa was measured with in vitro invasion assays. RESULTS: Both tumor cells and stroma expressed both MMP-2,9 and TIMP-1,2; It was found that MMP-2,9, TIMP-1,2 had a higher expression in patients with neck lymph node metastasis than those without metastasis (P < 0.05), positive percentage of MMP-2,9 in GNM was higher than that in TSCCa; The MMP-2,9 in node-positive patients was more active than in node-negative ones (P < 0.05); GNM had more active MMP-2, 9 and higher invasive potential than TSCCa. CONCLUSION: MMP-2,9 may play an important role in metastasis of oral squamous cell carcinoma; Elevation of TIMP-1,2 is likely to be the result of interaction of tumor and stroma.

Adult↗
PubMed2001

[Bcl-2, p53 expression and Epstein-Barr virus infection in primary nasopharyngeal carcinoma].

OBJECTIVE: To observe bcl-2, p53 gene expression and Epstein-Barr virus (EBV) infection and their relationship with clinicopathologic factors in primary nasopharyngeal carcinoma (NPC). METHOD: p53, bcl-2 proteins were assayed with immunohistochemical technique and EBV were assayed with polymerase chain reaction in 54 cases of NPC and 13 cases of chronic inflammation of nasopharyngeal epithelium (CINE). RESULT: The expression of p53, bcl-2 proteins and EBV were found respectively in 1(7.7%), 3(23.1%) and 1(7.7%) of 13 CINEs, which were significantly lower than those in 54 NPCs with respectively 41(75.9%), 48(88.9%) and 47(87%) (P < 0.01). In 39 cases of 54(72.2%) NPCs, we could find simultaneous p53, bcl-2 expression and EBV infection, furthermore, p53 and bcl-2 expression were significantly positively correlated with each other (r = 0.78, P < 0.01). p53 gene expression was significantly correlated with cervical lymph node metastasis of NPCs (P < 0.01). The expression of p53 in stage II, III, IV (92.9%, 78.9% and 100% respectively) were significantly higher than that in stage I (38.5%) (P < 0.01). CONCLUSION: The expression of p53, bcl-2 gene and EBV infection are the useful factors in the diagnosis of NPC, the overexpression of p53 is related with the stage and cervical lymph node metastasis of NPC, all the three play important roles in the pathogenesis of nasopharyngeal carcinoma.

Adolescent↗
PubMed2001

[The 5-year death analysis in patients with nasopharyngeal carcinoma treated with radiotherapy].

OBJECTIVE: To study the main death cause of nasopharyngeal carcinoma (NPC) treated with radiotherapy for 5 years. METHOD: An analysis had been made to evaluated the 5-year death in 165 patients with NPC treated with radiotherapy. RESULT: The death correlates strongly with the clinical stage, type and radiation dose (P < 0.05). CONCLUSION: The distant metastasis and local recurrence are the main death cause of NPC.

Adolescent↗
PubMed2001

[Structure characterization of melanin in black sesame by GC/MS].

Black sesame melanin, a kind of biopolymer was degraded by alkali fusion to study structure characterization. The degraded products were derivatized with bis-(trimethylsilyl) trifloroacetamide in a sealed tube at 125 degrees C for 30 min. The silylanization derivatives of degradation products were analyzed by GC/MS. Catechol, 1,4-dihydroxy benzene and catechuic acid were detected. This method can be used to characterize the structure type of black sesame melanin.

Catechin↗
PubMed2001

[A study on expression of tumor necrosis factor alpha in middle ear cholesteatoma and its effect on bone destruction].

OBJECTIVE: To determine the expression and localization of tumor necrosis factor alpha (TNF-alpha) in human middle ear cholesteatoma and its effects on bone resorption. METHOD: The distribution of TNF-alpha in 18 cholesteatoma tissues and 8 normal external ear canal skin, facial skin and tympanic membrane were studied immunohistochemically with paraffin-embedded sections. RESULT: TNF-alpha was localized in the epithelium and connective tissue of cholesteatomas studied, particularly on basal and spinous cells and macrophages. The epithelium of normal external ear canal skin, facial skin and tympanic membrane was slightly stained. CONCLUSION: This study revealed significantly increased level of TNF-alpha in cholesteatoma tissues. TNF-alpha acts both directly, by causing bone erosion as an autocrine growth factor, and indirectly as an important mediator by stimulating the release of enzymes causing bone destruction.

Adolescent↗
PubMed2001

[Permeation of buspirone hydrochloride across animal buccal mucosa and its mechanism].

AIM: To study the permeation of busprione hydrochloride across animal buccal mucosa and its permeation mechanism. METHODS: The in vitro penetration model was designed to investigate drug buccal mucosa permeability, and the influence factors (different animal oral mucosa, such as rabbit, guinea pig, pig, sheep and cow, drug concentrations and solution pH values) were measured. RESULTS: The permeability of rabbit buccal mucosa for busprione hydrochloride was the largest. The permeation rate was increased with solution pH and directly to the drug concentration. CONCLUSION: The transport way of busprione hydrochloride was passive diffusion and the transport channel was through cells.

Animals↗
PubMed2001

[Changes in SR Ca2+-ATPase activity, Ca2+ release and uptake kinetics of diaphragm muscle after different-frequency chronic electrical stimulation of diaphragmatic nerve].

To study adaptation of rabbit diaphragm muscle after different-frequency chronic electrical stimulation, Ca(2+)-ATPase activity and Ca(2+) release-uptake kinetics of sarcoplasmic reticulum (SR) were respectively measured by detecting inorganic phosphorus ion and Furo-2 fluorescence. SR Ca(2+)-ATPase activity of the low-frequency stimulation group was significantly lower than that of the control group (P<0.0l), but it was significantly higher in the high-frequency stimulation group against control (P<0.0l). The kinetics of Ca(2+) release and Ca(2+) uptake was significantly lower in low-frequency group than that of the control (P<0.0l), but the kinetics of Ca(2+) release and Ca(2+) uptake was significantly higher than that of the control (P<0.01). It is thought that different-frequency electrical stimulation induced different adaptative changes in SR Ca(2+)-ATPase activity, and Ca(2+) release and uptake kinetics of rabbit diaphragm muscle.

Animals↗