Nannochloropsis has been considered as a promising feedstock for biodiesel production in recent years. To improve its lipid productivity, heavy-ion irradiation mutagenesis, an effectively breeding method used in plants and microorganisms was applied in Nannochloropsis oceanica OZ-1. After large-scale screening using Imaging-PAM and microplate-reader, two mutants (HP-1 and HP-2) with higher growth rate were isolated from the wild type N. oceanica. Subsequently analysis showed that after 18 days of cultivation biomass accumulation of the HP-1 and HP-2 mutant was increased by 18% and 26% respectively compare to the wild type. Total lipid productivity of the HP-1 and HP-2 mutant was 295 mg/(L x d) and 275 mg/(L x d), respectively, whereas that of the wild type was 247 mg/(L x d). Both mutants showed significantly advantage over their wild type concerning biomass accumulation and lipid productivity.
Heavy Ions ; Lipids ; biosynthesis ; Microalgae ; growth & development ; metabolism ; radiation effects ; Mutagenesis ; genetics ; Mutation ; genetics ; Stramenopiles ; genetics ; metabolism ; radiation effects

Objective:To observe the preventive effects of infliximab in autoimmune hepatitis (AIH) and to explore its mechanism.Methods:The mice AIH model was established by injecting concanavalin A (Con-A) into the caudal vein. Forty mice were divided into prevention group and control group, with 20 mice in each group. The mice of prevention group were injected intravenously with infliximab (20 mg/kg) one hour before Con-A injection and the mice of control group were administrated with 200 μL phosphate buffered saline (PBS). Serum was collected 3, 8, 12 and 24 h after Con-A/PBS injection. The serum level of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) was detected by colorimetry. The level of cytokine interleukin (IL)-6, IL-1β, interferon gamma (IFN-γ), IL-4, IL-17A, IL-10 and chemokine C-X-C motif ligand 10 (CXCL10) was measured by enzyme-linked immunosorbent assay (ELISA). Liver samples were taken 12 h after Con-A/PBS injection for hematoxylin-eosin staining. Liver infiltrated lymphocytes were assessed by flow cytometry. The expression of T-box transcription factor 21 ( TBX21), GATA binding protein 3 ( GATA3), RAR related orphan receptor C ( RORC) and CXCL10 at mRNA level was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). The expression of CXCL10 in liver was detected by Western blotting. Paired t test and one-way analysis of variance were used for statistic analysis. Results:At 8, 12, and 24 h after Con-A injection, the serum ALT level, AST level, IL-1β and IFN-γ of prevention group were all lower than those of control group ((545.8±190.3) U/L vs. (865.8±237.7) U/L, (947.6±267.9) U/L vs. (1 448.0±403.5) U/L, (508.6±131.1) U/L vs. (976.6±207.6) U/L; (620.7±132.0) U/L vs. (952.9±106.8) U/L, (801.6±212.0) U/L vs. (1 424.8±236.0) U/L, (632.1±117.8) U/L vs. (1 008.3±187.5) U/L; (31.38±10.12) ng/L vs. (48.12±11.53) ng/L, (39.34±11.40) ng/L vs. (60.00±14.17) ng/L, (29.49±8.22) ng/L vs. (46.89±5.50) ng/L; and (432.93±66.82) ng/L vs. (674.66±97.88) ng/L, (655.09±169.17) ng/L vs. (937.90±166.36) ng/L, (263.40±54.97) ng/L vs. (410.74±86.64) ng/L), and the differences were statistically significant ( t = 2.350, 2.308, 4.263, 4.374, 4.860, 3.806, 2.440, 2.541, 3.939, 4.560, 2.660 and 3.210; all P<0.05). The serum IL-6 levels 3, 8, 12 and 24 h after Con-A injection of prevention group were all lower than those of control group ((1 075.79±303.77) ng/L vs. (1 914.48±317.80) ng/L, (1 945.97±271.85) ng/L vs. (2 100.80±378.42) ng/L, (1 578.60±504.54) ng/L vs. (2 525.40±406.55) ng/L, (1 020.64±280.03) ng/L vs. (1 582.00±311.96) ng/L), and the differences were statistically significant ( t=4.266, 2.903, 3.267 and 2.994; all P < 0.05). At 3 h after Con-A injection, serum CXCL10 level and CXCL10 mRNA expression in liver tissues of prevention group were both lower than those of control group ((1 755.8±148.1) ng/L vs. (2 102.0±334.0) ng/L and 7.20±3.00 vs. 27.60±1.90), and the differences were statistically significant ( t=2.356 and 2.623, both P<0.05). At 3 and 8 h after Con-A injection, T- bet expression at mRNA level in liver tissues of prevention group was lower than that of control group (6.94±2.29 vs. 15.20±3.48 and 9.38±3.48 vs. 18.17±4.48), and the differences were both statistically significant ( t = 4.427 and 3.673, both P<0.05). However, 3, 8, 12 and 24 h after Con-A injection, there were no statistically significant differences in serum IL-4, IL-17A, IL-10, or GATA3 or RORC expression at mRNA level between prevention group and control group (all P > 0.05). Conclusions:Infliximab has certain preventive effects in mice AIH model, which may be achieved by antagonizing TNF-α and decreasing the expression of CXCL10 in liver, reducing the infiltration of T-helper 1 cells and CD8 + T cells into liver, and by reducing T lymphocyte activation induced by inflammatory cytokines thus alleviating the damage of T lymphocytes to hepatocytes.

Objective To understand the prevalence,treatment and influence factors of hypertension in maintenance hemodialysis (MHD) patients in Anhui Province.Methods A total of 2724 adult patients on MHD from January 1st 2014 to March 31st 2014 in 26 hospitals of southern,northern and central Anhui Province were investigated.Their demographic characteristics,primary disease,complications,medications,dialysis and laboratory examination were explored.The prevalence treatment rate and control rate of hypertension were analyzed.Associated factors for controlling hypertension [systolic blood pressure (SBP) ＜ 140 mmHg and diastolic blood pressure (DBP) ＜ 90 mmHg] were assessed by logistic regression analysis.Results (1) The prevalence of hypertension in the hemodialysis patients was 87.0％.Their treatment rate and control rate were 93.2％ and 23.9％ respectively.The average of SBP was (145.90±21.18) mmHg,and the DBP on average was (83.60± 12.21) mmHg.The most commonly used anti-hypertensive drug is calcium channel blocker (88.2％).Over one third (45.7％) of patients were treated with two kinds of anti-hypertensive drug,26.2％ with 1 kind,21.7％ with 3 kinds,and 6.4％ with 4 kinds or more.(2) Compared with non-hypertension patients,patients with hypertension have older age,higher body mass index (BMI),phosphorus,SBP and DBP,as well as lower hemoglobin and Kt/V (all P ＜ 0.05).(3) The multivariate logistic regression analysis showed that Ca ＞ 2.50 mmol/L (OR=2.084,95％CI 1.008-4.307,P=0.047) positively correlated with controlling hypertension,while smoke (OR=0.594,95％CI 0.356-0.911,P=0.046) and BMI 18.5 ～ 23.9 kg/m2 (OR=0.516,95％CI 0.293-0.907,P=0.022) negatively correlated with it.Conclusions High prevalence yet low control rate of hypertension in MHD patients in Anhui Province were observed.Hypocalcemia may be a protective factor for hypertension control,while smoke and BMI may be risk factors for it.

WRKY is a superfamily of plant-specific transcription factors, playing a critical regulatory role in multiple biological processes such as plant growth and development, metabolism, and responses to biotic and abiotic stresses. Although WRKY genes have been characterized in a variety of higher plants, little is known about them in eukaryotic algae, which are close to higher plants in evolution. To fully characterize algal WRKY family members, we carried out multiple sequence alignment, phylogenetic analysis, and conserved domain prediction to identify the WRKY genes in the genomes of 30 algal species. A total of 24 WRKY members were identified in Chlorophyta, whereas no WRKY member was detected in Rhodophyta, Glaucophyta, or Bacillariophyta. The 24 WRKY members were classified into Ⅰ, Ⅱa, Ⅱb and R groups, with a conserved heptapeptide domain WRKYGQ(E/A/H/N)K and a zinc finger motif C-X4-5-C-X22-23-H-X-H. Haematococcus pluvialis, a high producer of natural astaxanthin, contained two WRKY members (HaeWRKY-1 and HaeWRKY-2). Furthermore, the coding sequences of HaeWRKY-1 and HaeWRKY-2 genes were cloned and then inserted into prokaryotic expression vector. The recombinant vectors were induced to express in Escherichia coli BL21(DE3) cells and the fusion proteins were purified by Ni-NTA affinity chromatography. HaeWRKY-1 had significantly higher expression level than HaeWRKY-2 in H. pluvialis cultured under normal conditions. High light stress significantly up-regulated the expression of HaeWRKY-1 while down-regulated that of HaeWRKY-2. The promoters of HaeWRKY genes contained multiple cis-elements responsive to light, ethylene, ABA, and stresses. Particularly, the promoter of HaeWRKY-2 contained no W-box specific for WRKY binding. However, the W-box was detected in the promoters of HaeWRKY-1 and the key enzyme genes HaeBKT (β-carotene ketolase) and HaePSY (phytoene synthase) responsible for astaxanthin biosynthesis. Considering these findings and the research progress in the related fields, we hypothesized that the low expression of HaeWRKY-2 under high light stress may lead to the up-regulation of HaeWRKY-1 expression. HaeWRKY-1 may then up-regulate the expression of the key genes (HaeBKT, HaePSY, etc.) for astaxanthin biosynthesis, consequently promoting astaxanthin enrichment in algal cells. The findings provide new insights into further analysis of the regulatory mechanism of astaxanthin biosynthesis and high light stress response of H. pluvialis.
Eukaryota ; Gene Expression Regulation, Plant ; Phylogeny ; Plant Proteins/metabolism* ; Plants/metabolism* ; Stress, Physiological/genetics* ; Transcription Factors/metabolism*