Four screening methods, colorimetric assay, blood-plate hemolysis method, surface tension activ- ity and oil spreading technique were introduced to isolate strains producing bio-demulsifiers from 6 different bacteria source samples. The results of various screening methods were evaluated in this paper. Seventeen demulsifying strains were obtained, which are qualified in demulsification test of kerosene model emulsions. Among them, 5 strains showed high demulsifying ability, achieving 70% plus demulsifying ratio within 24 hours. Petroleum-contaminated soil, excess sludge from biological process treating oilfield produced water and sludge from municipal wastewater treatment plant were the best among all tested sources. Due to the determination limit, the colorimetric assay and blood-plate hemolysis method are not competent to screen bio-demulsifiers strains. The measurement of surface tension and oil spreading method were easy but accu- rate methods to isolate bio-demulsifiers strains. Although demulsification test of model emulsion is an effec- tive technique to target strains with the capability of breaking emulsions, it is sophisticated and time-con- suming. Thus it is recommended to use surface tension and oil spreading methods in pre-screening and vali- date the results in demulsification test with kerosene model emulsions.

OBJECTIVETo fuse Legionella virulence gene (lvgA) with heat shock protein 60 gene (Hsp60) by PCR and detect the fusion gene expression in E.coli.

METHODSThe fragments of lvgA and Hsp60 genes having matching sequences at their ends to be fused were amplified from the genomic DNA of Legionella pneumophila by PCR, and the PCR products were mixed, denatured, reannealed, so that the strands with matching sequences at their 3' ends overlapped to serve as primers for each other. Extension of this overlap by DNA polymerase produced recombinant products. After amplification with outer primers, sufficient product of the fusion gene was harvested, which was inserted into the prokaryotic expression vector pGEX-4T-1 to construct the prokaryotic expression recombinant plasmid. After identification with restriction enzyme analysis, polymerase chain reaction and nucleotide sequence analysis, the E.coli BL21 containing the recombinant plasmid pGlvgA/Hsp60 was induced with IPTG and the expression of lvgA/Hsp60 was detected by SDS-PAGE and Western blot analysis.

RESULTSThe lvgA/Hsp60 fusion gene of 2,292 bp was amplified and the recombinant plasmid pGlvgA/Hsp60 was constructed successfully. A 117-kD GST-lvgA-Hsp60 fusion protein was detected in the E.coli containing the recombinant plasmid.

CONCLUSIONThe recombinant plasmid for Legionella pneumophila lvgA/Hsp60 fusion gene is constructed successfully and this fusion protein can be expressed in prokaryotic cells efficiently, which make possible the immunological characterization of this fusion gene.

Alternative Splicing ; Chaperonin 60 ; biosynthesis ; genetics ; Cloning, Molecular ; Escherichia coli ; genetics ; Gene Expression ; Gene Fusion ; Genetic Vectors ; Humans ; Legionnaires' Disease ; immunology ; prevention & control ; Plasmids ; genetics ; Polymerase Chain Reaction ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Vaccines, DNA ; biosynthesis ; immunology ; Virulence Factors ; biosynthesis ; genetics

Pulmonary hypertension (PH) is a progressive and fatal disease. The dysfunction of pulmonary artery endothelial cells (PAECs) is one of its important pathogenic factors. PAECs are monolayer flat epithelial cells, which play an important role in maintaining pulmonary vascular homeostasis. Studies have found that PAECs show damage and apoptosis at the early stage of PH development, while PAECs show anti-apoptotic characteristics at the late stage of PH development. The transition of PAECs into mesenchymal cells induced by hypoxic and inflammatory factors is also involved in the pathogenesis of PH. Carcinoid metabolism and mitochondrial dysfunction, bone mor- phogenic type 2 receptor mutation, epigenetic changes and inflammation of PAECs are the main pathogenesis of pulmonary vascular endothelial dysfunction in PH patients. New therapeutic measures targeting PAECs dysfunction are expected to play an important role in the treatment of PH in the future.

Adaptation to hypoxia of the plateau environment has been a focus of scientific research in decades. The geographical distributions of such living environment include the Qinghai-Tibet Plateau, Andean Plateau in South America and Ethiopian Plateau. Over the past century, the unique features of physiological adaptation to high-altitude chronic hypoxia have been documented scientifically. The genetic studies of hypoxic adaptation in the past decade have revealed genetic bases of human high-altitude adaptation, with a close relationship to the hypoxia inducible factor (HIF) pathway and hypoxia response elements (HREs). Interestingly, the genetic pattern of adaptation to hypoxia is not the same among the three plateau populations. Tibetan has developed the best high-altitude adaptation, with modification of the HIF pathway as the key genetic element. Due to the wide range of HIF pathways, HIFs could regulate hundreds of downstream genes and are closely related to various diseases such as cancer, inflammation, ischemia, acute organ damage and infection, etc. The treatment researches of these diseases through HIFs-related regulations have led to the development of stabilizers and inhibitors of HIF pathway. We review here the adaptive responses of the three plateau populations to the hypoxic environment, and the genetic mechanism of HIF and HREs in the different ethnic high-altitude populations. Classes of HIF inhibitors, such as PI3K and/or mammalian target of rapamycin (mTOR) inhibitors, DNA-binding inhibitors, histone deacetylase inhibitors, heat-shock protein 90 inhibitors, cardiac glycosides, transcription inhibitors, topoisomerase inhibitors, and HIF activators including 2-OG mimics, Fe²⁺ chelators, prolyl hydroxylase (PHD) active-site blockers and CUL2 deneddylators have been presented with the drug examples. In addition, the top 3 chemical-disease and chemical-gene (protein) co-occurrences have been presented from the Pubmed literature search. The review could serve as references for research of hypoxia adaptation and HIF-related diseases.

Pulmonary hypertension is a rapidly progressing disease of the lung vasculature with poor prognosis, ultimately leading to right heart failure and death. The remodeling of small pulmonary arteries represents an important pathological characteristic of pulmonary hypertension. Pulmonary arterial smooth muscle cells (PASMCs) located in the middle layer of pulmonary artery exhibit hyperproliferation and resistance to apoptosis, which is the main initiator of pulmonary vascular remodeling and similar to that seen in tumor cells. In this review we focus on the signaling pathways that play a key role in PASMCs proliferation and the latest research progress on inhibitors targeting cell proliferation pathways to provide a new perspective for the treatment of PH．

Pulmonary hypertension (PH) is a kind of disease characterized by progressive increase of pulmonary vascular resistance and occlusive vascular remodeling. Hypoxic inductive factor-2α (HIF-2α) plays an important role in the abnormal proliferation of pulmonary vascular cells and pulmonary vascular remodeling. This review focuses on the role of HIF-2α in pulmonary hypertension at the cellular and the global level, and candidates targeting HIF-2α for the treatment of pulmonary hypertension, in order to better understand the pathogenesis of PH and find effective treatments.

OBJECTIVE: To explore the mechanism of electroacupuncture (EA) for the regulation of lipid production and improvement in obesity by mediating Wnt/β-catenin pathway through activating silent information regulator 1 (SIRT1). METHODS: Of 75 Wistar male rats, 10 rats were selected randomly as the normal group and fed with standard diet. The rest rats were fed with high-fat diet for 8 weeks to establish the obesity model. Forty rats of successful modeling were randomized into a model group, an EA group, an EA plus inhibitor group (EA+I group) and an agonist group, 10 rats in each one. In the EA group, EA was applied at "Guanyuan" (CV 4), "Zhongwan" (CV 12), "Zusanli" (ST 36) and "Fenglong" (ST 40), with continuous wave, 2 Hz in frequency and around 1 mA in intensity. The needles were retained for 20 min. In the EA+I group, sirtinol solution was injected from caudal vein and EA was exerted simultaneously. In the agonist group, resveratrol solution was given by intragastric administration. The intervention of the above three groups was given once every two days, 3 times a week, consecutively for 8 weeks. Before and after intervention, body mass and Lee's index were recorded in the rats of each group. After intervention, the levels of serum total cholesterol (TC), triglyceride (TG) and free fatty acid (FFA) were detected in the rats of each group. After intervention, the mass of white adipose tissue (WAT) and the area of adipocytes were compared in the rats among the 5 groups. Using Western blot method, the protein expressions of SIRT1, glycogen synthase kinase-3β (GSK3β), β-catenin, cyclin D1 and peroxisome proliferators-activated receptor γ (PPARγ) were detected in WAT in the rats of each group. RESULTS: After intervention, compared with the model group, the body mass and Lee's index were reduced in the rats of the EA group and the agonist group ( CONCLUSION Electroacupuncture remarkably improves the body mass, Lee's index and blood lipid metabolism and reduces WAT mass and adipocyte size in obesity model rats, which is probably related to up-regulating the protein expression of SIRT1 in WAT, activating Wnt/β-catenin pathway and inhibiting the expression of PPARγ of downstream lipogenic gene so as to affect lipid production.
Acupuncture Points ; Animals ; Electroacupuncture ; Male ; Obesity/therapy* ; Rats ; Rats, Wistar ; Sirtuin 1/genetics* ; Triglycerides ; beta Catenin/genetics*