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1.  Profiling bacterial diversity in a limestone cave of the western Loess Plateau of China 
Bacteria and archaea sustain subsurface cave ecosystems by dominating primary production and fueling biogeochemical cyclings, despite the permanent darkness and shortage of nutrients. However, the heterogeneity and underlying mechanism of microbial diversity in caves, in particular those well connect to surface environment are largely unexplored. In this study, we examined the bacterial abundance and composition in Jinjia Cave, a small and shallow limestone cave located on the western Loess Plateau of China, by enumerating and pyrosequencing small subunit rRNA genes. The results clearly reveal the contrasting bacterial community compositions in relation to cave habitat types, i.e., rock wall deposit, aquatic sediment, and sinkhole soil, which are differentially connected to the surface environment. The deposits on the cave walls were dominated by putative cave-specific bacterial lineages within the γ-Proteobacteria or Actinobacteria that are routinely found on cave rocks around the world. In addition, sequence identity with known functional groups suggests enrichments of chemolithotrophic bacteria potentially involved in autotrophic C fixation and inorganic N transformation on rock surfaces. By contrast, bacterial communities in aquatic sediments were more closely related to those in the overlying soils. This is consistent with the similarity in elemental composition between the cave sediment and the overlying soil, implicating the influence of mineral chemistry on cave microhabitat and bacterial composition. These findings provide compelling molecular evidence of the bacterial community heterogeneity in an East Asian cave, which might be controlled by both subsurface and surface environments.
PMCID: PMC4378288  PMID: 25870592
bacterial diversity; cave; rock surface; pyrosequencing; elemental composition; 16S rRNA
2.  Serum Interleukin-37 Concentrations and HBeAg Seroconversion in Chronic HBV Patients During Telbivudine Treatment 
IL-37 is a new anti-inflammatory cytokine that plays an important role in protecting against tissue injury during infections via limiting immune and inflammatory reactions. This study aimed at determining serum IL-37 concentrations and HBeAg seroconversion in chronic hepatitis B virus (HBV) patients during Telbivudine (LDT) treatment. The serum levels of IL-37 were determined using enzyme-linked immunosorbent assay (ELISA) in 40 chronic hepatitis B virus infection (CHB) patients (HBeAg positive), 30 chronic hepatitis C virus infection (CHC) patients [25 with spontaneously resolved hepatitis C virus (SR-CHC)], and 30 healthy controls (HCs). Anti-inflammatory cytokines such as IL-2 and IL-10 were measured using cytometric bead array, and the concentrations of clinical parameters such as serum hepatitis B surface antigen (HBsAg), hepatitis B nucleocapsid antigen (HBeAg), alanine transaminase (ALT), aspartate transaminase (AST), HBV DNA, and hepatitis C virus (HCV) RNA loads were measured. It was found that the serum levels of IL-37 were higher in chronic HBV patients with high virus loads, but the association was not statistically significant. The serum levels of IL-37 were decreased in HBeAg seroconverted CHB patients after 48 weeks of LDT treatment. The serum levels of IL-37 had no significant difference in CHC patients compared with SR-HCV and HCs. The levels of anti-inflammatory cytokine, IL-2 and IL-10, were lower in CHB and CHC patients than the HC, but IL-2 levels increased after LDT treatment in CHB patients. The concentrations of serum IL-37 in CHB and CHC patients with abnormal levels of serum ALT (>50 U/L) or AST (>40 U/L) were significantly higher than CHB, CHC patients with normal levels of ALT (<50 U/L) or AST (<40 U/L). These results suggest that IL-37 may play a significant role in the immune response of CHB patients with HBeAg seroconversion. The serum levels of IL-37 are associated with liver damage in CHB patients.
PMCID: PMC3793653  PMID: 23697556
3.  Cyclic precipitation variation on the western Loess Plateau of China during the past four centuries 
Scientific Reports  2014;4:6381.
Precipitation variation on the Loess Plateau (LP) of China is not only important for rain-fed agriculture in this environmentally sensitive region, but also critical for the water and life securities over the whole Yellow River basin. Here we reconstruct high resolution precipitation variation on the western LP during the past 370 years by using two replicated, annually-laminated stalagmites. Spatial analysis suggests that the reconstruction can be also representative for the whole LP region. The precipitation variations show a significant quasi-50 year periodicity during the last 370 years, and have an important role in determining the runoff of the middle Yellow River. The main factor controlling the decadal scale variations and long-term trend in precipitation over this region is southerly water vapour transport associated with the Asian summer monsoon. The Pacific Decadal Oscillation is also an important influence on precipitation variation in this region, as it can affect the East Asian summer monsoon and the West Pacific Subtropical High.
PMCID: PMC4165273  PMID: 25223372
4.  Serum IL-33 Levels Are Associated with Liver Damage in Patients with Chronic Hepatitis B 
This aim of this study was to assess the potential role of IL-33 in the pathogenic process of chronic hepatitis B (CHB). The levels of serum IL-33 and soluble ST2 (sST2) in CHB patients and healthy controls (HC) were determined using enzyme-linked-immunosorbent serologic assay, and the Th1 (IFN-γ, TNF–α, IL-2) and Th2 (IL-4, IL-6, IL-10) cytokines by cytometric bead array. It was found that the levels of serum IL-33 in CHB patients were significantly higher than that of HC at the base line, but decreased after treatment with adefovir dipivoxil for 12 weeks. The levels of serum sST2, as a decoy receptor of IL-33, were significantly higher in CHB patients than the HC. There was no correlation between the levels of serum sST2 and IL-33. The concentrations of serum Th1 (IFN-γ, IL-2) and Th2 (IL-6, IL-10) cytokines in CHB patients significantly increased after treatment compared to the baseline. These results suggest that IL-33 is involved in the pathogenesis of CHB and that adefovir dipivoxil therapy can attenuate the production of IL-33 in patients with CHB.
PMCID: PMC3366095  PMID: 22304300
5.  Interplay between the Westerlies and Asian monsoon recorded in Lake Qinghai sediments since 32 ka 
Scientific Reports  2012;2:619.
Two atmospheric circulation systems, the mid-latitude Westerlies and the Asian summer monsoon (ASM), play key roles in northern-hemisphere climatic changes. However, the variability of the Westerlies in Asia and their relationship to the ASM remain unclear. Here, we present the longest and highest-resolution drill core from Lake Qinghai on the northeastern Tibetan Plateau (TP), which uniquely records the variability of both the Westerlies and the ASM since 32 ka, reflecting the interplay of these two systems. These records document the anti-phase relationship of the Westerlies and the ASM for both glacial-interglacial and glacial millennial timescales. During the last glaciation, the influence of the Westerlies dominated; prominent dust-rich intervals, correlated with Heinrich events, reflect intensified Westerlies linked to northern high-latitude climate. During the Holocene, the dominant ASM circulation, punctuated by weak events, indicates linkages of the ASM to orbital forcing, North Atlantic abrupt events, and perhaps solar activity changes.
PMCID: PMC3431539  PMID: 22943005

Results 1-5 (5)