[Quantitative assessment of surface hydrological connectivity in Momoge National Nature Reserve, Northeast China]. / èŽ«èŽ«æ ¼å›½å®¶çº§è‡ªç„¶ä¿æŠ¤åŒºåœ°è¡¨æ°´æ–‡è¿žé€šæ€§å®šé‡è¯„ä¼°.

Quantitative assessment of hydrological connectivity is a hot but difficult issue in current research. Using the 30-m resolution global monthly surface water remote sensing dataset released by the EU Joint Research Center and three indicators of geostatistical connectivity, maximum distance of connection (MDC), and surface water extent of connectome (i.e., seasonally connected water bodies), we quantified the hydrological connectivity of surface water in Momoge National Nature Reserve in different months of a normal year (May to October 2016), and in September of different hydrological years (a wet year, namely 1998; a normal year, namely 2016; a drought year, namely 2002), and different directions (west-east and north-south). Our results showed that: 1) the geostatistical connectivity function (GCF) along the west-east direction was better than that along the north-south direction. The GCF in August and July was better than that in other months. The GCF along the west-east direction of each hydrological year was better than that in the drought year, whereas the GCF in the drought year was better than the corresponding value in the normal year. The GCF along the north-south direction in each hydrological year was better than that in the normal year, whereas the GCF in the normal year was better than that in the drought year. The MDC along the west-east direction in June, July, September, and October of the normal year was all concentrated at 25.26 km. MDC was more concentrated along the north-south direction, with 10 km for all months. The MDC in the normal and drought years was relatively close, but both were much smaller than that in the wet year. 2) frequent seasonal connections between the Yuelianghu Reservoir and the Nenjiang River, and between Etoupao and its neighboring lakes occurred in the study area during the normal year, while most of the other lakes remained isolated. The patterns of hydrological connection in the study area differed across different hydrological years: two giant connectomes were formed in the wet year, some lakes are periodically connected in the normal year, and all lakes remain isolated in the drought year. 3) As a drainage area for farmland receding water, the surface water extent of the Etoupao connectome increased visibly during the three water supplement seasons (spring, summer, and autumn). By quantifying the surface hydrological connectivity in Momoge National Nature Reserve with multiple water sources from different perspectives, our results provide a scientific basis for wetland protection and restoration and integrated management of watershed water resources.

[Review on wetland water level monitoring using interferometric synthetic aperture radar]. / å¹²æ¶‰åˆæˆå­”å¾„é›·è¾¾ç›‘æµ‹æ¹¿åœ°æ°´ä½ç ”ç©¶ç»¼è¿°.

Water level is an important indicator of wetland hydrological regime. Detection of wetland water levels through interferometric synthetic aperture radar (InSAR) has outstanding advantage, including high spatial resolution, high accuracy, low cost, and high efficiency. We introduced prerequisites for the monitoring of wetland water levels with InSAR, discussed the types of InSAR techniques, the influencing factors for monitoring wetland water levels and their advantages and disadvantages. There are three prerequisites for effectively detecting wetland water levels with InSAR techniques: 1) the presence of emergent aquatic plants; 2) the main backscattering mechanism is double bounce scattering; and 3) the interferometric coherence exceeds a certain threshold. Current water level monitoring techniques have been developed from traditional InSAR techniques to advanced InSAR techniques, such as STBAS, MM, and DSI. These techniques evolve from detecting relative water level changes to estimate absolute water level and water depth time series. The influencing factors of InSAR techniques for monitoring wetland water levels include operating para-meters of the synthetic aperture radar (SAR) and characteristics of the wetlands themselves. Finally, we proposed the key directions for future research in this field: i) investigating the potential use of specific water level monitoring techniques in other regions with different backscattering and interferometric coherence characteristics; ii) developing new algorithms to integrate multi-sensor, multi-track, multi-band, multi-polarization, and multi-temporal InSAR repeat-pass observation; iii) considering alternative sources of SAR data; and (iv) strengthening research on "by-products" of wetland water level monitoring with InSAR, such as wetland hydrological connectivity, flow direction, and flow regime.

Gene variation in IL10 and susceptibility to chronic hepatitis B.

OBJECTIVES: To evaluate the correlation between IL-10 gene polymorphisms and hepatitis B infection. METHODS: Tag single nucleotide polymorphisms (SNPs) were used to investigate the relationship between IL-10 gene polymorphisms and susceptibility to chronic hepatitis B virus (HBV) infection by comparing 996 chronic HBV infection cases to 301 acute infection controls. RESULTS: This study found that rs3024490 G/T allele, located in the intron 1 region and highly prevalent in Chinese populations, was significantly different between the chronic HBV infection cases and the acute infection controls in single allele analysis, genetic models analysis, and haplotypes analysis. CONCLUSIONS: This suggested that the rs3024490 within IL-10 was associated with susceptibility to chronic hepatitis B in a Chinese Han population.

[Long-term immunogenicity and effectiveness of live attenuated hepatitis A vaccine (H2-strain)-a study on the result of 15 years' follow up].

OBJECTIVE: To evaluate the long-term immunogenicity and effectiveness of live attenuated hepatitis A (HA) vaccine (H2 strain) after one dose injection, through a 15 years' follow up observation. METHODS: A total of 220 children with negative anti-HAV antibody (aged 1-3 y) were involved and followed up in Jiaojiang district, Taizhou city, Zhejiang province. Indicators would include seroconversion and geometric mean titer (GMT) levels after inoculation the vaccine with single dose at 2 m, 12 m, 6 years, 10 years and 15 years. Epidemiological observation was carried out within the 15 years to evaluate the relationship between vaccine coverage, the incidence of HA and the overall effectiveness. In the studied population, serum was tested by ELISA (calibrated by WHO international reference) and ABBOTT Axsym HAVAB mEIA. RESULTS: Seroconversion rates were found to be 98.6% and 81.3% after 2 months and 15 years of inoculation and slowly decreased. GMT level was 128 mIU/ml after 15 years, significantly higher than the required protective level of 20 mIU/ml, recommended by WHO experts. Effectiveness through the 15-year follow up program showed a significant correlation between vaccine coverage and incidence of HA in 1-15 years aged group (Kendall-Rank test, τ =-0.931, P<0.01). There was no HA case seen among the observed accumulated 236 413 person-year vaccines, compared to 4 HA cases discovered in the 27 206 person-year of the non-vaccinees. The overall protective rate reached 100%. Through a mass vaccination program on children, the whole population established an immune-defence to enable the incidence of HA decreased by 96.7%. CONCLUSION: The long-term immunogenicity and effectiveness of live attenuated hepatitis A vaccine (H2 strain) after one dose injection could last as long as 15 years.

[Relationship between the expression of P-glycoprotein, glutathione S-transferase-pi and thymidylate synthase proteins and adenosine triphosphate tumor chemosensitivity assay in cervical cancer].

OBJECTIVE: To explore the feasibility of the adenosine triphosphate-tumor chemosensitivity assay (ATP-TCA) in human cervical cancer chemosensitivity testing and to analyze the relationship between the three drug resistance-associated proteins: P-glycoprotein (P-gp); glutathione S-transferase-pi (GST-pi); thymidylate synthase (TS) and ATP-TCA. METHODS: ATP-TCA was used to detect the sensitivity of 35 specimens of fresh cervical cancer to six cytotoxic drugs as follows: paclitaxel (TAX), cisplatin (DDP), bleomycin (BLM), gemcitabine (GEM), 5-fluorouracil (5-FU), irinotecan (CPT-11). Consecutive sections from 35 cases of cervical cancer were assessed immunohistochemically for expression of P-gp, GST-pi and TS proteins. RESULTS: (1) Thirty-two of 35 assays were completed successfully, with an evaluability rate of ATP-TCA at 91% (32/35). There was a marked heterogeneity of chemosensitivity in cervical cancer. The ex vivo sensitive rate of TAX was 88% (28/32), of 5-FU 72% (23/32), of GEM 62% (20/32), of DDP 19% (6/32), of BLM 16% (5/32), and of CPT-11 12% (4/32). (2) The expression of GST-pi and TS protein in cervical cancer was 66% (21/32) and 44% (14/32), which was associated with the resistance to DDP and 5-FU ex vivo (P=0.011, P=0.022), respectively; but the expression of P-gp protein was not associated with any resistance to TAX, 5-FU, GEM, DDP, BLM or CPT-11 ex vivo (P>0.05). CONCLUSIONS: ATP-TCA could be used to individualize chemotherapy by selecting agents for particular patients of cervical cancer. The expression of GST-pi and TS protein might be useful biomarkers to predict the resistance to DDP and 5-FU in patients with cervical cancer.

[Preliminary study on RT-PCR-ELISA method for virus titer testing of live attenuated hepatitis A vaccine].

OBJECTIVE: To evaluate the RT-PCR-ELISA method applied for testing live attenuated hepatitis A vaccine titer. METHODS: A solid phase hybridization-enzyme colorimetric detection method was used for detecting specific nucleic acid. Primer labeled with biotin was used to amplify viral gene fragment, then the product was quickly hybridized with the specific probe covalently coupled on DNA-binding microplate wells. Finally, peroxidase-labeled streptavidin was used in colorimetric detection. The results were judged by reading A value. Eleven batches of live attenuated hepatitis A vaccine titer were tested by this method. The results were compared with that of routine cell culture method (CCID50). RESULTS: The sensitivity was similar to routine cell culture method (P>0.05). This method was convenient, fast and specific. CONCLUSION: CCID50 method may be replaced by the RT-PCR-ELISA method in evaluating the titer of live attenuated hepatitis A vaccine.