Simulation and attribution analysis of terrestrial ecosystem carbon storage of Hainan Island from 2015 to 2050.

Terrestrial ecosystem carbon storage (TECS) could significantly affect the concentration of atmospheric CO2, which is critical for climate change prediction. Along these lines, the Integrated Valuation of Ecosystem Services and Trade-offs model was employed to determine the TECS of Hainan Island (HN) from 2015 to 2050 accurately. Besides, the Future Land-use Simulation model combined with natural and anthropogenic factors was used to forecast the land-use types from 2025 to 2050 in HN by considering different Shared-socioeconomic pathway-Rrepresentative concentration pathway (SSP-RCP) scenarios. Finally, the geographical detector explored the influence mechanism concerning the TECS. Under the SSP1-RCP1.9 scenario, the TECS of HN will be gradually increased to 388.10 million tons in 2050, mainly due to the increase in forest areas and the fact that the majority of grassland in the western part of HN is being converted into forest. Under different SSP-RCP scenarios except for SSP1-RCP1.9, HN's TECS is expected to gradually decrease from 2015 to 2050, mainly due to the loss of grassland and forest in coastal low-altitude areas. From the single/pair factor perspective influenced mechanism concerning the TECS, the elevation (DEM) and DEM∩Slope were found to be the dominant single/pair factor under the SSP1-RCP1.9, SSP1-RCP2.6 and SSP2-RCP4.5 scenarios. The least distance to residential area (LDP) and LDP∩LDR (i.e. LDP and least distance to roads or railways) were found to be the dominant factors under the SSP3-RCP7.0, SSP4-RCP3.4, SSP4-RCP6.0, SSP5-RCP3.4 and SSP5-RCP8.5 scenarios. Besides, the pair factors provided a higher determinant power for TECS than a single factor. Given the results of the TECS and the influence mechanism concerning the TECS under different SSP-RCP scenarios, we suggest reasonably planning the transportation network and limiting the disorderly expansion of construction land.

DNA starvation/stationary phase protection protein of Helicobacter pylori as a potential immunodominant antigen for infection detection.

BACKGROUND: Application of chicken egg yolk immunoglobulin Y (IgY) for Helicobacter pylori (H. pylori, HP) has gained much interest in recent years. Comparing with for treatment, IgY may be more advantageous when used for H. pylori detection. METHODS: Nine strains of H. pylori with different genetic backgrounds were inactivated and used to immunize hens, respectively, for the preparation of polyclonal anti-H. pylori immunoglobulin Y (anti-HP IgY). The proteins of H. pylori with reactivity to anti-HP IgY were detected by Western Blot. The five protein bands that can be well recognized by anti-HP IgY of each group, and were prevalent in all nine strains were excised from SDS-PAGE gel, digested and identified by Nano-HPLC-MS/MS analysis. The potential of these identified proteins as antigen detection targets was then assessed by sequence analysis. RESULTS: Anti-HP IgY derived from each group of specific strain immunized hens can recognize self-strain and non-self-strain antigens well. Five immunodominant antigens were identified as chaperonin GroEL, flagellin A, urease subunit alpha, peroxiredoxin and DNA starvation/stationary phase protection protein. Sequences analysis showed that both peroxiredoxin and DNA starvation/stationary phase protection protein were present in all 1000 strains of H. pylori queried, and the amino acid sequences were highly conserved. The highest sequence consistency between the DNA starvation/stationary phase protection protein of H. pylori and non-Helicobacter organisms was 52.59%, and the consistent sites were scattered and there was no continuous long fragment consensus sequence. CONCLUSION: DNA starvation/stationary phase protection protein was identified as an immunodominant antigen of H. pylori and sequence analysis indicated that it could serve as a potential antigen target for the diagnosis of H. pylori infection.

Distribution characteristics of the sabA, hofC, homA, homB and frpB-4 genes of Helicobacter pylori in different regions of China.

BACKGROUND: Helicobacter pylori (H. pylori) encodes numerous outer membrane proteins (OMPs), with considerable geographic heterogeneity and related to different clinical outcomes. This study aimed to investigate the distribution characteristics of five important OMP genes (sabA, hofC, homA, homB and frpB-4) in different regions of China. MATERIALS AND METHOD: A total of 266 strains were isolated from 348 stomach biopsy specimens in Shandong, Guangxi, Heilongjiang, Hunan, and Qinghai provinces. The presence of sabA, hofC, homA, homB and frpB-4 gene was detected by polymerase chain reaction (PCR) from H. pylori genomic DNA. RESULTS: Among the strains in five regions, the prevalence of frpB-4 was 100% and that of hofC was 97.7%. The prevalence of homB in the isolates from Qinghai (45.5%) was significantly lower than that in Shandong (75.3%), Guangxi (76.9%) and Hunan (69.6%) (P<0.05). The frequency of homA in Shandong (30.1%) was significantly lower than in Guangxi (57.7%) and Qinghai (63.6%) (P<0.05). The prevalence of the sabA gene in Shandong, Guangxi, Heilongjiang, Hunan and Qinghai provinces was 21.9%, 59.7%, 45.9%, 52.2%, and 18.2%, respectively (P<0.05). The sabA "on" status was significantly more frequent in isolates from Guangxi (46.8%), Heilongjiang (37.8%), and Hunan (47.8%) than Qinghai (3.0%) (P<0.05). The presence of homA and sabA genes may be negatively correlated with the development of gastritis. There was no significant association between the frpB-4, hofC, homB gene and clinical outcomes. CONCLUSION: The prevalence of homA, homB, and sabA genes and the sabA "on" or "off" status have significant geographical differences among five provinces in China. The presence of homA and sabA genes may be protective factors of gastritis.