[Spectral characteristics analysis and remote sensing inversion of water quality parameters in Han Shiqiao wetland].

The research object of the present paper is the water quality of Han Shiqiao wetland water. Water spectrum and quality parameters were measured on the site and in the lab. The authors simulated the relationships between water quality parameters and the best bands or combination, and built the multiple linear regression equation to obtain characteristic spectrum of the key water quality parameters. Besides, several key issues involved in applying ASTER satellite imagery to water quality include atmospheric correction, discussing methods for ASTER data bands analysis, and choosing the best bands and band combination. Results indicated that although the simulation model is not universal, the analysis of spectral characteristics based on ground spectrometer could provide foundations for the choice of remote sensing characteristics bands. The band ratio of water quality parameters simulated from ASTER spectral characteristics moves to relatively long-wave band. Finally, based on the analysis of ASTER remote sensing characteristics bands, the authors built water quality parameters regression model. The models for water quality parameters were recommended, and the accuracies of these models were analyzed. Making use of regression model, we executed spatial distribution map of water quality parameters to achieve wetland water monitoring with remote sensing in terms of variation in space and with time.

Interactions between effects of estrogen receptor gene polymorphisms on BMD and experiences of the first spermorrhea in Chinese Han boys.

OBJECTIVE: To study the interaction between polymorphisms of estrogen receptor (ER) gene and puberty on bone mineral density (BMD). METHODS: One hundred and forty-six boys aged 13-17 years were divided into two groups according to their first spermorrhea. DNA was analyzed for Xba I and Pvu II genotypes by PCR-RFLP. BMD of the total body, forearm and lumbar spine was measured by dual-energy X-ray absorptiometry (DXA). The relationship between polymorphisms of ER gene and BMD in these two groups was analyzed. RESULTS: The BMD at all sites in the spermorrhea group was significantly higher than that in the un-spermorrhea group. The independent contribution of ER genotypes to BMD at two pubertal stages was analyzed after adjusting co-variables. In the un-spermorrhea group, the BMD at distal 1/10 and 1/3 forearm of those carrying pp genotype was significantly higher than that of the non-carries, whereas in the spermorrhea group BMD in those carrying the same genotype was significantly lower than that in the non-carriers. Similar results were obtained by haplotype analysis. Multiple stepwise regression analysis showed that body weight, age and the first spermorrehea were the dominant determinants for BMD. BMD at forearm might be influenced by interaction between ER genotype and the first spermorrehea. CONCLUSION: The polymorphisms of ER gene play a different role in BMD influenced by the first spermorrhea. Chinese boys carrying p or x allele should pay more attention to their bone mass.

Molecular mechanism of icariin on rat asthmatic model.

BACKGROUND: Effects of icariin on airway inflammation in asthmatic rats and the intervention of LPS induced inflammation are interfered with the machanism of icariin. Our study aimed to observe the effect of icariin on ovalbumin-induced imbalance of Th1/Th2 cytokine expression and its mechanism. METHODS: Sixty male SD rats were randomly divided into control group (PBS), asthma group (ovalbumin (OVA)-induced), dexamethasone group, and OVA+icariin low, medium and high dose groups (5, 10, 20 mg/kg, respectively). Each group had ten rats. The model of OVA sensitization was a rat asthma model. Enzyme-linked immunosorbent assay (ELISA) method was used to observe the effects of icariin on interleukin-4 (IL-4) and inerferon γ (IFN-γ) in rats' lung tissue. Immunohistochemical staining was applied to detect the intervention effects of icariin on T cells (T-bet) and gatabinding protein 3 (GATA-3) in rat pulmonary tissue. Realtime RT-PCR was used to observe the intervention effects of icariin on T-bet and GATA-3 mRNA expression in rat pulmonary tissue and spleen lymphocytes. Western blotting was used to observe the icariin intervention effects on T-bet, GATA-3 and nuclear factor-Kappa B (NF-κB) p65 protein expressions in rat pulmonary tissue. RESULTS: The ELISA results from pulmonary tissue showed that IL-4 expression was significantly reduced (P < 0.05), while the IFN-γ expression increased but not significantly when we compared OVA+icariin medium and high dose groups with the asthma group. Immunohistochemical staining of pulmonary tissue showed that the GATA-3 decreased significantly while the T-bet staining did not change in the OVA+icariin high dose group. In pulmonary tissue and spleen lymphocytes T-bet and GATA-3 mRNA expressions were significantly reduced (P < 0.05) in icariin treatment groups compared with the asthma model group. GATA-3 and T-bet mRNA in rat spleen lymphocytes in the asthma group were higher than in the control group. GATA-3 mRNA expression in pulmonary tissue significantly decreased (P < 0.05) while T-bet mRNA expression decreased but not significantly in the icariin treatment group compared with the asthma group. T-bet and GATA-3 protein expressions in pulmonary tissue increased significantly compared with the asthma group, which meant that icariin could inhibit the increase of GATA-3 protein, but not of T-bet. The bronchus, blood vessels and periphery pulmonary tissue had infiltration of inflammatory cells in the OVA+icariin high dose group while NF-κB p65 cells were reduced, and expression of NF-κB p65 in this group was less than in the asthma group. The expression of total p65 protein decreased with icariin treatment while the expression of cytoplasmic p65 protein increased. CONCLUSIONS: Icariin could regulate the imbalance of Th1/Th2 cytokines in asthmatic rat pulmonary tissue. Icariin could regulate the imbalance of Th1/Th2 associated transcription factors T-bet and GATA-3 in asthmatic rat pulmonary tissue and spleen lymphocytes. Icariin could inhibit the activation of NF-κB p65 protein in asthmatic rat pulmonary tissue.

[The relation between body mass index and percentage body fat among Chinese adolescent living in urban Beijing].

OBJECTIVE: To study the relation between body mass index (BMI) and percentage body fat (PBF) in Chinese adolescent, and to compare the prevalence of overweight and obesity using BMI or PBF standards. METHODS: BMI from 757 girls with an average aged of 10.1 years in the rural areas, 165 girls average aged 13.5 years in suburbs and 172 boys average aged 13.7 years in suburb of Beijing, were measured. Their body compositions were also measured by dual-energy X-ray absorptiometry (DEXA). RESULTS: BMI was found closely correlated with PBF in each age group of rural and suburb girls and suburb boys with the correlation coefficient(r) of 0.59 - 0.83. When age, height and pubertal development were controlled, r became 0.54 - 0.88. The prevalence rates of obesity in rural girls, suburb girls and suburb boys were 33.1%, 21.8% and 21.5%, when PBF cutoff values (girls: PBF >or= 35%, boys: PBF >or= 25%) were used. However, the rates became 2.4%, 3.0% and 4.0% when BMI cutoff values of International Obesity Task Force (IOTF) were used. Compared with PBF cutoff values for obesity, the IOTF recommended BMI cutoff values had relatively lower sensitivity (7.3% - 18.9%) and higher specificity (100%). CONCLUSION: BMI correlated well with PBF in Beijing adolescent. IOTF-BMI cutoff values showed low sensitivity and high specificity to Chinese adolescent which might be suitable for identifying obesity but not for the purpose of screening.