Biodegradation of pyridine pollutant by microorganisms is one of the economical and effective methods to solve the environmental pollution of pyridine under high salinity conditions. To this end, screening of microorganisms with pyridine degradation capability and high salinity tolerance is an important prerequisite. In this paper, a salt-resistant pyridine degradation bacterium was isolated from the activated sludge of Shanxi coking wastewater treatment plant, and identified as a bacterium belonging to Rhodococcus on the basis of colony morphology and 16S rDNA gene phylogenetic analysis. Salt tolerance experiment showed that strain LV4 could grow and degrade pyridine with the initial concentration of 500 mg/L completely in 0%-6% saline environment. However, when the salinity was higher than 4%, strain LV4 grew slowly and the degradation time of pyridine by strain LV4 was significantly prolonged. Scanning electron microscopy showed that the cell division of strain LV4 became slower, and more granular extracellular polymeric substance (EPS) was induced to secrete in high salinity environment. When the salinity was not higher than 4%, strain LV4 responded to the high salinity environment mainly through increasing the protein content in EPS. The optimum conditions for pyridine degradation by strain LV4 at 4% salinity were 30 ℃, pH 7.0 and 120 r/min (DO 10.30 mg/L). Under these optimal conditions, strain LV4 could completely degrade pyridine with an initial concentration of 500 mg/L at a maximum rate of (29.10±0.18) mg/(L·h) after 12 h adaptation period, and the total organic carbon (TOC) removal efficiency reached 88.36%, indicating that stain LV4 has a good mineralization effect on pyridine. By analyzing the intermediate products in pyridine degradation process, it was speculated that strain LV4 achieved pyridine ring opening and degradation mainly through two metabolic pathways: pyridine-ring hydroxylation and pyridine-ring hydrogenation. The rapid degradation of pyridine by strain LV4 in high salinity environment indicates its application potential in the pollution control of high salinity pyridine environment.
Rhodococcus/genetics* ; Phylogeny ; Extracellular Polymeric Substance Matrix/metabolism* ; Sewage ; Biodegradation, Environmental ; Pyridines/metabolism*

The aim of this study is to determine the regulatory mechanism of PTEN-induced putative kinase protein 1 short isoform (PINK1S) in cytoplasm. By co-immunoprecipitation (Co-IP) assay, we identified that PINK1S interacted with the beta regulatory subunit of Casein Kinase 2 (CK2β), but not with the catalytic subunits CK2α1 and CK2α2. Furthermore, cells were transfected with PINK1S and CK2β, and then PINK1S was purified by immunoprecipitation. After detecting the phosphorylated proteins by Phos-tag Biotin, we found that CK2β overexpression increased auto-phosphorylation of PINK1S. Finally, we generated CK2β knockdown cell lines by RNA interference. Purified PINK1S from CK2β knockdown cells significantly reduced its auto-phosphorylation compared with control cells. These results suggested that CK2β functions as a regulatory subunit of PINK1S kinase complex promoted its activation by self-phosphorylation.
Biotin ; Casein Kinase II ; metabolism ; Cell Line ; Gene Knockdown Techniques ; Humans ; Phosphorylation ; Protein Kinases ; metabolism ; Pyridines ; RNA Interference ; Transfection

OBJECTIVETo investigate the effects of E 4031, a sodium calcium exchanger (NCX) agonist, on the isolated cardiac function and resting Ca2+ level in myocardial cells from rats with chronic heart failure.

METHODSRats chronic heart failure model was established by abdominal aorta coarctation with; Isolated heart perfusion by Langendorff apparatus was used to detect heart function and the effects of E 4031 on haemodynamic indexes; Myocardial cells of rats in the model group were extracted quickly and co-incubated with calcium fluorescent indicator fluo3/AM and the impact of E 4031 on the fluorescence intensity in myocardial cells were evaluated by confocal microscopy.

RESULTSHeart function of rats in the model group detected by Langendorff perfusion was significantly reduced after 12 weeks, E 4031 at 10 micromol/L could improve their left ventricular developed pressure(LVDP) and systolic / diastolic maximum rate (+/- dp/dtmax). Compared with the control and sham operation groups, the resting Ca2+ fluorescence intensity of the myocardial cells of rats in model group was at a higher level and went through a process of transient rise and drop, then stably remaining at a low level after co-incubated with 10 micromol/L E 4031.

CONCLUSIONE 4031 can improve the isolated heart function of rats with chronic heart failure, which may be associated with its enhancing the activity of NCX in the myocardial cell membrane and stabilizing intracellular Ca2+ level.

Animals ; Calcium ; metabolism ; Disease Models, Animal ; Heart ; physiopathology ; Heart Failure ; metabolism ; physiopathology ; In Vitro Techniques ; Male ; Myocardium ; metabolism ; Myocytes, Cardiac ; metabolism ; Piperidines ; pharmacology ; Pyridines ; pharmacology ; Rats ; Rats, Wistar

OBJECTIVETo explore the pharmacologic mechanism of gardenin in treating cerebral ischemia, by studying its effect on gene expression profile in brain of rats with focal cerebral ischemia (FCI).

METHODSTotal RNAs were isolated from rats with FCI and those treated with gardenin. The mRNAs were reversely transcribed to cDNA with incorporation of fluorescent Cy5- or Cy3-dUTP to prepare hybridization probes. The PCR products of 4096 genes were spotted on the chip after a serial treatment. The mixed probes were hybridized to the cDNA microarray. Axon Genepix 4000B and GenePixPro 3.0 software were used to scan and analyze the fluorescent signals.

RESULTSIn the group treated with gardenin, there were 70 genes had expression profiles different to that in the model group in the focal cerebral ischemic brain tissue, in which 68 were up-regulated and 2 down-regulated.

CONCLUSIONGardenin has regulatory effect on the gene expression in rats with focal cerebral ischemia, which elucidates part of the pharmacologic mechanism of Qingkailing in molecular level.

Animals ; Brain Ischemia ; genetics ; metabolism ; Gene Expression Profiling ; Gene Expression Regulation ; drug effects ; Male ; Pyridines ; pharmacology ; Rats ; Rats, Sprague-Dawley

To investigate the effect of SB203580, a p38MAPK specific inhibitor, on ropivacaine-induced cytotoxicity in PC12 cells.
 Methods: PC12 cells were divided into three groups: the normal group (Group N), cells were cultured for 48 h; the ropivacaine group (Group R), cells were cultured with 15 mmol/L ropivacaine hydrochloride for 48 h; the ropivacaine+SB203580 group (Group R+S), cells were cultured with 15 mmol/L ropivacaine hydrochloride plus 10 μmol/L SB203580 for 48 h. The cell survival rates were detected by MTT assay. The protein levels of cleaved caspase-3, phosphor-p38 (p-p38) and cystolic cytochrome C (Cyt C) were detected by Western blotting.
 Results: Compared with the Group N, the number and survival rate of PC12 cells in the Group R and the Group R+S were significantly reduced (all P<0.05); the number and survival rate of PC12 cells in the Group R+S were significantly higher than those in the Group R (both P<0.05). Compared with the Group N, the levels of p-p38 and cleaved caspase-3, and the content of cytoplasmic Cyt C in the PC12 cells from the Group R and the Group R+S were significantly enhanced (all P<0.05); compared with the Group R, the levels of p-p38 and cleaved caspase-3, and the content of cytoplasmic Cyt C in the PC12 cells from the Group R+S were decreased (all P<0.05).
 Conclusion: The ropivacaine-induced cytotoxicity can be attenuated via inhibition of p38MAPK; which is related to decrease in Cyt C content and cleaved caspase-3 expression.
Anesthetics, Local ; toxicity ; Animals ; Apoptosis ; Imidazoles ; PC12 Cells ; Pyridines ; Rats ; Ropivacaine ; toxicity ; p38 Mitogen-Activated Protein Kinases ; metabolism

OBJECTIVETo investigate the roles of p38 MAPK in apoptosis of the normal liver cell, the paratumor cirrhosis hepatocellular cell and the hepatocellular carcinoma cell.

METHODSThree cell lines were adopted (the normal liver cell line HL-7702, the paratumor cirrhosis hepatocellular cell line QSG-7701 and the hepatocellular carcinoma cell line QGY-7703) and treated with Diamminedichloroplatin (DDP, cisplatin) and p38MAPK inhibitor SB203580. The apoptosis and cell cycles were detected by flow cytometry and electromicroscopy. The expressions of p38MAPK, CDC25B, p34cdc2 and cyclinB1 were detected by immunocytochemical staining , confocal microscopy and western blot.

RESULTSThe apoptotic rates in all three cell lines pretreated with DDP increased obviously and the rates in normal liver cells and HCC cells increased continuously even after SB203580 treatment, whereas in paratumor cirrhosis cells the rate decreased and the cell cycle stopped at S phase.

CONCLUSIONCisplatin induces apoptosis in the paratumor cirrhosis hepatocellular cell line QSG-7701 via activation of p38MAPK pathway and it differs in the normal liver cells from the hepatocellular carcinoma cells.

Apoptosis ; drug effects ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Cell Line, Tumor ; Cisplatin ; pharmacology ; Humans ; Imidazoles ; pharmacology ; Liver Neoplasms ; metabolism ; pathology ; Pyridines ; pharmacology ; p38 Mitogen-Activated Protein Kinases ; metabolism

OBJECTIVETo explore the role of p38 signal pathway in regulating matrix metalloproteinase-9 (MMP-9) expression and brain edema formation in a rat model of traumatic brain injury (TBI).

METHODSA total of 130 adult male Sprague Dawley rats were randomly divided into 4 groups, namely the normal group (n=10), sham-operated group (n=40), TBI (induced by Feeney free falling methods) group (n=40), and SB group with intraperitoneal SB203580 treatment (10 µmol/L) 15 min before TBI (n=40). The rats were sacrificed 2 h and 2 days after TBI. The expressions of p38, p-p38, and MMP-9 mRNA and protein were detected by RT-PCR and Western blotting. The blood brain barrier permeability was detected by Evans Blue (EB) test, and the brain water content (BWC) was determined using a gravimetric technique.

RESULTSThe expression of p-p38 protein increased markedly 2 h after TBI (P<0.05), and was suppressed by SB203580 treatment (P<0.05). MMP-9 mRNA and protein showed no obvious increase at 2 h after TBI, but significantly increased at 2 days as compared with those in the sham-operated group (P<0.05). MMP-9 mRNA and protein were much lower in SB group than in TBI group 2 days after TBI (P<0.05). The blood brain barrier permeability significantly increased 2 h after TBI (P<0.05) and kept increasing until 2 days (P<0.05), but was reduced significantly by SB203580 (P<0.05). BWC increased obviously 2 days after TBI (P<0.05) and was lessened by SB203580 (P<0.05).

CONCLUSIONBlocking p38 signal pathway can attenuate MMP-9 upregulation and brain edema after TBI, suggesting the important role of p38 in regulating MMP-9 expression to affect traumatic brain edema.

Animals ; Brain Edema ; pathology ; Brain Injuries ; metabolism ; Enzyme Inhibitors ; pharmacology ; Imidazoles ; pharmacology ; MAP Kinase Signaling System ; Male ; Matrix Metalloproteinase 9 ; metabolism ; Pyridines ; pharmacology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the effects of extremely low frequency electromagnetic field (ELF-EMF) on human osteosarcoma cells and its mechanisms.

METHODSHuman osteosarcoma MG-63 cells were exposed to 50 Hz,1 mT ELF-EMF for 1, 2 and 3 h in vitro, with or without pretreatment by reactive oxygen species (ROS) inhibitor N acetylcysteine (NAC) or p38MAPK inhibitor SB203580. The proliferation of MG-63 cells was determined by MTT method; the apoptosis rate and ROS level in MG-63 cells were detected by flow cytometry. The expression of p38MAPK in MG-63 cells was determined by Western blotting.

RESULTSELF-EMF decreased the viability of MG-63 cells, inhibited cell growth, induced cell apoptosis and increased the level of ROS significantly. The apoptosis rate declined significantly after treatment with ROS inhibitor NAC or p38MAPK inhibitor SB203580. After exposure to ELF-EMF, p38MAPK in MG-63 cells was activated, and the phosphorylation level was also inhibited after treatment with NAC.

CONCLUSIONELF-EMF can induce the apoptosis of MG-63 cells. Increased ROS and p38MAPK activation may be involved in the mechanism.

Acetylcysteine ; Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Electromagnetic Fields ; Humans ; Imidazoles ; Osteosarcoma ; pathology ; Oxidative Stress ; Phosphorylation ; Pyridines ; Reactive Oxygen Species ; metabolism ; p38 Mitogen-Activated Protein Kinases ; metabolism

Microbial nitrilases have attracted increasing attention in nitrile hydrolysis for carboxylic acid production in recent years. A bacterium with nitrilase activity was isolated and identified as Pseudomonas putida CGMCC3830 based on its morphology, physiological and biochemical characteristics, as well as 16S rRNA gene sequence. The nitrilase production was optimized by varying culture conditions using the one-factor-at-a-time method and response surface methodology. Glycerol 13.54 g/L, tryptone 11.59 g/L, yeast extract 5.21 g/L, KH2PO4 1 g/L, NaCl 1 g/L, urea 1 g/L, initial pH 6.0 and culture temperature 30 degrees C were proved to be the optimal culture conditions. It resulted in the maximal nitrilase production of 36.12 U/mL from 2.02 U/mL. Investigations on substrate specificity demonstrate P. putida nitrilase preferentially hydrolyze aromatic nitriles. When applied in nicotinic acid synthesis, 2 mg/mL P. putida cells completely hydrolyzed 20.8 g/L 3-cyanopyridine into nicotinic acid in 90 min. The results indicated P. putida CGMCC3830 displayed potential for industrial production of nicotinic acid.
Aminohydrolases ; biosynthesis ; Culture Media ; Hydrolysis ; Niacin ; biosynthesis ; Nitriles ; metabolism ; Pseudomonas putida ; enzymology ; Pyridines ; metabolism ; RNA, Ribosomal, 16S ; genetics ; Substrate Specificity ; Temperature

The adventitious root of Tripterygium wilfordii was used as experiment material to study effects of various concentration of aspartic acid, isoleucine, cysteine and arginine in MS medium on the growth and triptolide, wilforgine, wilforine contents of the adventitious roots. The results showed that compared with the control, supplemented with 0.25 mmol x L(-1) aspartic acid at 3rd week, the growth of the adventitious roots only accounted for 80%, but the content of triptolide of the adventitious roots and the medium was 1.36, 1.30 times, the content of wilforgine was 1.16, 1.37 times, the content of wilforine was 1.22, 1.63 times, respectively. At 3rd week 0.05 mmol x L(-1) isoleucine, the growth of adventitious roots was 97.3%, wilforgine of adventitious roots and medium 1.02, 1.27 times, wilforine 1.36 times and 1.15 times. At 1st week 0.25 mmol x L(-1) cysteine, the growth of the adventitious roots comprised 77.5% of the control, while content of triptolide of adventitious roots reached 1.87 times. At 2nd week 1.00 mmol x L(-1) cysteine, the growth of adventitious roots was 44.6% of the control, the content of wilforine in medium was 2.97 times. At 3rd week 0.50 mmol x L(-1) arginine, the growth of adventitious roots was 124.2%, the content of wilforgine and wilforine was 1.3, 1.4 times, respectively.
Amino Acids ; analysis ; metabolism ; Diterpenes ; analysis ; Epoxy Compounds ; analysis ; Lactones ; analysis ; metabolism ; Phenanthrenes ; analysis ; Plant Roots ; chemistry ; growth & development ; metabolism ; Pyridines ; analysis ; metabolism ; Secondary Metabolism ; Tripterygium ; chemistry ; growth & development ; metabolism