BFGF attenuates aortic valvular interstitial cell calcification by inhibiting endoplasmic reticulum stress-mediated apoptosis.

The potential protective effect of basic fibroblast growth factor (BFGF) on the cardiovascular system has been proposed previously, however, its effect on calcific aortic valve disease (CAVD) and underlying mechanisms have not been elucidated. The valvular interstitial cell (VIC) were isolated from porcine aortic valve leaflets. To investigate the effect of BFGF on osteogenic differentiation of VIC, the osteogenic induced medium (OIM) and BFGF were added. The protein expression level was detected by Western blot, and apoptosis was determined by flow cytometry. The effect of BFGF on CAVD process in vivo was assessed by a rat CAVD model, which was identified by echocardiography and Alizarin red staining. The expression level of BFGF in the aortic valve and serum were significantly upregulated in CAVD patients compared to control group. In addition, exogenous BFGF injection attenuates CAVD process in vivo. The protein markers of osteogenic differentiation, endoplasmic reticulum stress (ERS), and apoptosis were significantly upregulated by culture with OIM. On the contrary, the aforementioned proteins were suppressed after adding 100 ng/mL of BFGF. Inhibition of PI3K/Akt and ERK1/2 pathways by specific inhibitors abolished the protective effect of BFGF. In conclusion, BFGF could alleviate the VIC calcification by inhibiting ERS-mediated apoptosis, which is partly regulated by activation of the PI3K/Akt and ERK1/2 signaling pathways. BFGF may provide a potential avenue for CAVD therapy.

Degradation of acid orange 7 (AO7) by a bacterium strain Flavobacterium mizutaii L-15.

Acid orange 7 (AO7) is an azo dye widely used in the dyeing and direct printing industry. AO7 is an environmental pollutant because the cleavage of azo bonds produces aromatic amines, which are considered mutagenic and carcinogenic. Microbial degradation is one of the most effective methods to remove environmental pollutants. A bacterium strain L-15 was isolated from the wastewater treatment system of a dye manufacturer. This strain is capable of decolorizing AO7. The strain was identified as Flavobacterium mizutaii based on its morphological, physiological and biochemical characteristics, and the sequence of 16S rDNA. The AO7-degrading characteristics and the effects of culture condition on the degrading efficiency of the strain were investigated by shake-flask culturing. The optimal degradation condition of L-15 was 30 °C and pH 7.0. After culturing at 30 °C for 3 days with the initial AO7 concentration of 20 mg/L, the degradation rate of AO7 was 60.45%. The optimal salt concentration was lower than 2%.

pH-dominated niche segregation of ammonia-oxidising microorganisms in Chinese agricultural soils.

Ammonia-oxidising archaea (AOA) are increasingly recognised as the primary mediators of soil ammonia oxidation, particularly in acidic soils. To explore the niche segregation of AOA and ammonia-oxidising bacteria (AOB) and the potential effect of this segregation on nitrification rates and the nitrogen cycle in Chinese agricultural soils, AOA and AOB amoA gene databases were established, and 454 high-throughput sequencing was used to investigate the key factors leading to the niche segregation of these two types of microorganisms. qPCR results demonstrated that there were more functional genes for AOA than for AOB in most of the soils. AOA diversity was higher than AOB diversity in most of the soils with AOA operational taxonomic units (OTU) numbers ranging from 40 to 169 and AOB OTU numbers ranging from 18 to 105. pH was the most important factor influencing the community structure of AOA (P < 0.01) and AOB (P < 0.05), and acidophilic AOA (i.e. Nitrosotalea-related sequences) were dominant in soils with pH values below 6.0. In addition, AOA amoA gene copy numbers were significantly positively correlated with pH (P < 0.05), the ratio of AOA OTU numbers/AOB OTU numbers was significantly negatively correlated with pH (P < 0.05), and the percentage of sequences represented by the Nitrosotalea cluster was significantly negatively correlated with pH (P < 0.01).

Effect of different ammonia concentrations on community succession of ammonia-oxidizing microorganisms in a simulated paddy soil column.

Ammonia oxidation is performed by both ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). To explore the effect of ammonia concentration on the population dynamic changes of ammonia-oxidizing microorganisms, we examined changes in the abundance and community composition of AOA and AOB in different layers. Most of the archaeal amoA sequences were Nitrosotalea-related and the proportion that Nitrosotalea cluster occupied decreased in the surface layer and increased in the deep layer during the cultivation process. Nitrosopumilus-related sequences were only detected in the deep layer in the first stage and disappeared later. Both phylogenetic and quantitative analysis showed that there were increased Nitrosomonas-related sequences appeared in the surface layer where the ammonia concentration was the highest. Both AOA and AOB OTU numbers in different layers decreased under selective pressure and then recovered. The potential nitrification rates were 25.06 µg · N · L(-1) · g(-1) dry soil · h(-1) in the mid layer which was higher than the other two layers. In general, obvious population dynamic changes were found for both AOA and AOB under the selective pressure of exogenous ammonia and the changes were different in three layers of the soil column.

[Production of 5-aminolevulinic acid from organic industrial wastewater by photosynthetic bacteria].

OBJECTIVE: We used Rhodopseudomonas strains with high-yield of 5-aminolevulinic acid (ALA) to produce ALA from wastewater of producing monosodium glutamate, citric acid, beer, and soybean product. METHODS: Cultivation was carried out under anaerobic light condition (3000 Lux) at 30 degrees C. For comparison, we tested the addition of levulinic acid (LA), glycin and succinate to the substrate to increase the production of ALA, effect of sterilization of the wastewater for both strains. Cell mass concentration (OD660) and the content of ALA were determined with spectrophotometer. RESULTS: Without adding levulinic acid (LA), glycin and succinate, the growth of strain 99-28 reached plateau after 72-96 h. The maxiam ALA production was obtained at 96 h. Both the yield of ALA and the Chemical Oxygen Demand (CODcr) removal rate of monosodium glutamate waster water were the highest in all tested wasterwaters. When LA, glycin and succinate were added, ALA production of strain 99-28 was significantly increased whereas the CODcr removal was adversely affected. Non-sterial wasterwater slightly reduced the growth and CODcr removal rate of strain 99-28, however the ALA production could be strongly reduced with the addition of LA, glycin and succinate. The growth and CODcr removal of mutant strain L-1 was similar with strain 99-28, but its ALA production was much higher than that of strain 99-28. CONCLUSION: The Rhodopseudomonas strains screened in our laboratory can use organic wasterwater as substrates to produce ALA and remove CODcr.

Preparation and characterization of N-succinyl-N'-octyl chitosan micelles as doxorubicin carriers for effective anti-tumor activity.

N-Succinyl-N'-octyl chitosan (SOC) was prepared and characterized by elemental analysis, FTIR, (1)H NMR, WAXD and TG. An anticancer drug, doxorubicin (DOX), was incorporated into polymeric micelles forming by SOC in aqueous solutions. Critical micelle concentrations (CMC) of SOC were determined by fluorescence spectroscopy. The DOX-loaded SOC micelles were characterized by measurement of size and drug loading. The loading content of DOX increased with increasing drug-to-carrier ratio, and the more amount of the octyl chain, the higher the drug loading content. The average size, which was affected by the amount of octyl chain and drug loading content, was in the range of 100-200 nm. The polymeric micelles containing doxorubicin in the core region exhibited a sustained release and more cytotoxic activity against HepG2, A549, BGC and K562 than doxorubicin alone, this can be attributed to an endocytosis mechanism rather than passive diffusion.