Patterns of tree species richness in Southwest China.

As a region known for its high species richness, southwest China plays an important role in preserving global biodiversity and ensuring ecological security in the Yangtze, Mekong, and Salween river basins. However, relatively few studies focus on the response of tree species richness to climate change in this part of China. This study determined the main tree species in southwest China using the Vegetation Map of China and the Flora of China. From simulations of 1970 to 2000 and three forecasts of future benign, moderate, and extreme climate warming anticipated during 2061 to 2080, this study used a maximum entropy model (MaxEnt) to simulate main tree species richness in southwest China. Regions with a peak species richness at intermediate elevations were typically dominated by complex mountainous terrain, such as in the Hengduan Mountains. Likewise, regions with the smallest richness were low-elevation areas, including the Sichuan Basin, and the high-elevation Sichuan-Tibet region. Annual precipitation, minimum temperature of the coldest month, temperature seasonality, and elevation were the most critical factors in estimating tree species richness in southwest China. During future 2061 to 2080 climate scenarios, tree species tended to migrate towards higher elevations as mean temperatures increased. For climate change scenarios RCP2.6-2070 (benign) and RCP4.5-2070 (moderate), the main tree species richness in the study area changed little. During the RCP8.5-2070 extreme scenario, tree species richness decreased. This study provides useful guidance to plan and implement measures to conserve biodiversity.

Olf1/EBF associated zinc finger protein interfered with antinuclear antibody production in patients with systemic lupus erythematosus.

INTRODUCTION: The aim of the study was to determine whether Olf1/EBF associated zinc finger protein (OAZ), a transcription factor encoded by a positional systemic lupus erythematosus (SLE) candidate gene, plays a functional role in the pathogenesis in SLE. METHODS: Gene expression levels in peripheral blood cells (PBLs) measured using quantitative real-time polymerase chain reaction (qPCR) were assessed for association with disease activity and the presence of specific autoantibodies. Peripheral blood mononuclear cells (PBMCs) were incubated with specific siRNAs for three days, then cells were harvested for measuring mRNA levels using qPCR, and supernatants for levels of total immunoglobulin (Ig)G and IgM as well as secreted cytokines, chemokine and antinuclear antibodies (ANA) using ELISA. Indirect immunofluorescence was also applied for ANA detection. RESULTS: OAZ gene expressions in PBLs from 40 ANA-positive SLE patients were significantly increased than those from 30 normal controls (P < 0.0001) and 18 patients with rheumatoid arthritis (P < 0.01). In SLE patients, OAZ transcripts were positively correlated with SLE disease activity index (SLEDAI) score (r = 0.72, P < 0.0001) and higher in those positive for anti-dsDNA or anti-Sm antibodies (both P < 0.05). Co-culturing with OAZ siRNAs reduced mRNA levels of OAZ by 74.6 +/- 6.4% as compared to those co-cultured with non-targeting siRNA and OAZ silencing resulted in reduced total IgG, ANA, interferon (IFN)-gamma, interleukin (IL)-10, IL-12 and IL-21, but elevated CCL2 levels in culture supernatants (P < 0.05). The declined ANA levels correlated with inhibited OAZ expression (r = 0.88, P = 0.05), reduced IL-21 levels (r = 0.99, P < 0.01), and elevated chemokine (C-C motif) ligand 2 levels (r = -0.98, P < 0.01). Expressions of ID1-3 were significantly down-regulated by 68.7%, 70.2% and 67.7% respectively after OAZ silence, while ID3 was also highly expressed in SLE PBLs (P < 0.0001) and associated with disease activity (r = 0.76, P < 0.0001) as well as anti-dsDNA or anti-Sm antibodies (both P < 0.05). CONCLUSIONS: Elevated expression of OAZ transcripts in SLE PBLs were strongly correlated with disease activity. Suppression of OAZ expression inhibited downstream ID levels, and secretion of ANA and IL-21, implicating a role of OAZ pathway in the pathogenesis of SLE.

[Evaluating type I interferon-inducible gene expression in patients with systemic lupus erythematosus.].

OBJECTIVE: To explore the expression levels of interferon-inducible genes in patients with systemic lupus erythematosus (SLE), and to validate these gene expressions as potential biomarkers for the differentiation of disease flare and infection. METHODS: Peripheral blood was obtained from 48 SLE, 16 rheumatoid arthritis (RA) patients and 26 normal controls, and total RNA was extracted and reverse transcribed into complementary DNA. Real-time PCR technique was used to determine the gene expressions of MX1, OASL, OAS1, ISG15 and LY6E at transcription level. Univariate logistic regression analysis and multivariate conditional logistic regression model were applied to analyze 5 related factors for infection or activity. RESULTS: (1) The expression levels of MX1, OASL, OAS1, ISG15, and LY6E mRNA in SLE patients were significantly increased as compared with normal controls (P all < 0.01), while the expression levels of OASL, OAS1, ISG15 and LY6E mRNA in SLE patients were also higher than those in RA patients (P all < 0.05). (2) There were no significant difference between male and female patients of the 5 gene expression in SLE patients. (3) By logistic regression analysis, ISG15 and LY6E were independent risk factors for active SLE patients (P < 0.01), OASL expression was an independent risk factor for SLE patients with infection (P = 0.003). CONCLUSION: All the 5 interferon inducible genes are highly expressed in SLE patients, in which ISG15 and LY6E are independently associated with disease flare, while OASL may be helpful for the evaluation of infection in SLE patients.

[Gene expression of OAZ pathway in the patients of systemic lupus erythematosus].

OBJECTIVE: To explore the role of Olf/EBF associated zinc finger protein (OAZ) pathway in the RNA expression level in patients with systemic lupus erythematosus (SLE). METHODS: The expression levels of OAZ, BMP6, BMP4, Id3, Smad6, EHZF genes were valuated in bone marrow progenitor cells of 5 SLE patients and 5 normal subjects and replicated in peripheral blood cells of 30 SLE patients and 20 normal individuals by using real-time quantitative PCR technique. Relationships of the expression levels of OAZ, BMP6, BMP4, Id3 mRNA with disease activity and other clinical indices were analyzed. RESULTS: The expression levels of OAZ and Id3 mRNA (deltaCt) in the bone marrow (10.6 +/- 0.5, 5.8 +/- 3.2) and peripheral blood (14.1 +/- 2.7, 7.5 +/- 1.8) of SLE patients significantly increased than those observed in normal controls (16.5 +/- 0.9, 10.4 +/- 2.6, 16.1 +/- 2.2, 9.5 +/- 1.7), which was found to negatively correlate with SLEDAI score, renal lesion index , titers of anti-dsDNA and anti-RNA antibodies, but positively correlate with serum complement C3. Expression levels of BMP4 and BMP6 were differentially expressed in peripheral blood cells but not bone marrow progenitor cells. CONCLUSIONS: OAZ pathway is involved in the pathogenesis of SLE. Further investigation is required for the understanding of the function of these abnormally expressed genes.