Biological nitrogen removal with enhanced phosphate uptake in (AO)2 SBR using single sludge system

Simultaneous biological phosphorus and nitrogen removal with enhanced anoxic phosphate uptake via nitrite was investigated in an anaerobic-aerobic-anoxic-aerobic sequencing batch reactor ((AO)2 SBR). The system showed stable phosphorus and nitrogen removal performance, and average removals for COD, TN and TP were 90%, 91% and 96%, respectively. The conditions of pH 7.5-8.0 and temperature 32 degrees C were found detrimental to nitrite oxidation bacteria but favorable to ammonia oxidizers, and the corresponding specific oxygen uptake rates(SOUR) for phase 1 and 2 of nitrification process were 0.7 and 15 mgO2/(gVSS x h) in respect, which led to the nitrite accumulation in aerobic phase of (AO)2 SBR. Respiratory tests showed that 40 mgNO2-N/L did not deteriorate the sludge activity drastically, and it implied that exposure of sludge to nitrite periodically enabled the biomass to have more tolerance capacity to resist the restraining effects from nitrite. In addition, batch tests were carried out and verified that denitrifying phosphorus accumulation organisms (DPAOs) could be enriched in a single sludge system coexisting with nitrifiers by introducing an anoxic phase in an anaerobic-aerobic SBR, and the ratio of the anoxic phosphate uptake capacity to aerobic phosphate uptake capacity was 45%. It was also found that nitrite (up to 20 mgNO2-N/L) was not inhibitory to anoxic phosphate uptake and could serve as an electron acceptor like nitrate, but presented poorer efficiency compared with nitrate.

A novel approach to treat combined domestic wastewater and excess sludge in MBR

Domestic wastewater was treated by combined anaerobic biofilm-aerobic membrane bioreactor(MBR) process, and part biomass MBR was withdrawn to treat with ozone, then the ozonated sludge was returned to anaerobic inlet. In aerobic MBR, MISS and DO were controlled at 3000-3500 mg/L and 0.8 mg/L respectively. Comparing the experimental results of two stages, it was noticed that ozonation did not affect the removal efficiency for organics but had a significant influence on the removals of NH3-N and TN. During the ozonation period of two months, no excess sludge was wasted, and a zero sludge yield was obtained.

[The effects of cell growth factors on proliferation and migration of coronary artery endothelial cells]

AIM

To study the effects of hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) on proliferation and migration of bovine coronary artery endothelial cells (BCAEC) in vitro.

METHODS

BCAECs were isolated and cultured in vitro, and divided into control group, VEGF group and HGF group. BCACEs proliferation were measured using MTT, and their migration was observed using reverse microscope.

RESULTS

The OD value of control, VEGF and HGF group were 0.22 +/- 0.01, 0.40 +/- 0.14, 0.44 +/- 0.15 respectively. The proliferation ratio of BCAECs in VEGF and HGF group was 81.8% +/- 16.9%, 100.0% +/- 21.1% respectively. There was no migration in control group, but significant migration in VEGF and HGF group.

CONCLUSION

Both VEGF and HGF can promote proliferation and migration of BCAECs, the effect of HGF is stronger than VEGF.

Generator sources of EEG large waves elicited by mental stress of memory recall or mental calculation

Preceding mental sweating response (MSR) during mental stress, small wavelets and large waves are observed on EEG. In the present study, locations of current sources of the large waves were estimated. The results revealed that the current dipole was estimated around the orbits, reflecting activity of the eyelid or eye muscles.

Microwave-assisted [6+4]-cycloaddition of fulvenes and alpha-pyrones to azulene-indoles: facile syntheses of novel antineoplastic agents

A microwave-enhanced [6+4]-cycloaddition reaction between 6-aminofulvene and pyrones followed by CO(2) extrusion provides azulene-indoles which display interesting antineoplastic activity.

Lipopolysaccharides induce p8 mRNA expression in vivo and in vitro

Systemic LPS endotoxin is associated with acute pancreatic damage. Whether damage results from direct interaction of LPS with pancreatic cells is unknown. We addressed that question by monitoring p8 expression in reponse to LPS, in vivo and in vitro, because overexpression of the p8 protein is a sensitive marker of pancreatic agression. For in vivo studies, rats were sacrificed at different times after a single intraperitoneal injection of LPS, and pancreas, liver, kidney, lung, brain, and intestine were processed for RNA preparation. In vitro, pancreatic acinar AR4-2J cells were cultivated with 0.1, 1, or 10 micrograms/ml LPS for 6, 12, or 24 h. p8 mRNA expression was monitored by Northern blotting. In vivo, it was strongly increased in the pancreas after 12 h of treatment and remained elevated after 24 h. It was also induced in kidney and liver, with a maximum at 6 and 12 h, respectively, but not in lung, brain, or intestine. In AR4-2J cells, basal p8 mRNA expression was very low and increased in a time- and dose-dependent manner after treatment with LPS. LPS-induced overexpression of p8 mRNA in vivo confirmed the adverse effect of endotoxemia on pancreas and its overexpression in vitro demonstrated a direct interaction of LPS with pancreatic cells.

Thymic microenvironments, 3-D versus 2-D?

Lympho-stromal interactions in the thymus crucially de- termine the fate of developing T cells. Epithelial cells, inter- digitating reticular cells, macrophages and fibroblasts all play a role in the shaping of the T cell repertoire. Recently published evidence shows that lympho-stromal interaction acts bi-directional. Developing T cell themselves, at different stages of differentiation, control the microarchitecture of thymic microenvironments, a phenomenon designated as 'crosstalk'. This paper reviews experiments showing that developing T cells crosstalk to different thymic epithelial cells in a stepwise fashion. In this way, correctly organized thymic microenvironments guarantee normal thymopoiesis.

[Effects of "qing kai ling" injection on experimental cerebral hematoma in rabbits]

OBJECTIVE

To observe the effect of "Qingkailing" (QKL) on cerebral hematoma.

METHODS

The experimental cerebral hematoma models were produced by injecting autogenous clot in the rabbit. The influences of QKL on blood gas, brain index, contents of water, sodium, potassium, calcium, magnesium in brain tissues and changes of cerebrovascular permeability, histomorphology at the third day, seventh day, fourteenth day after cerebral hematoma were observed.

RESULTS

In the pathological group brain index and contents of water, sodium, calcium of brain tissue, ventilation of lung were increased progressively, cerebrovascular permeability were raised obviously, especially in the side of hematoma (right brain). After the forming of cerebral hematoma cerebral edema was reduced, brain index, contents of water, sodium, calcium in brain tissue and cerebrovascular permeability, hyperventilation were all less than pathological group and close to the control group.

CONCLUSION

QKL was advantageous in the treatment of encephal edema induced by experimental cerebral hematoma.

The thiostrepton-resistance-encoding gene in Streptomyces laurentii is located within a cluster of ribosomal protein operons

A common approach to identify and clone biosynthetic gene from an antibiotic-producing streptomycete is to clone the resistance gene for the antibiotic of interest and then use that gene to clone DNA that is linked to it. As a first step toward cloning the genes responsible for the biosynthesis of thiostrepton (Th) in Streptomyces laurentii (Sl), the Th resistance-encoding gene (tsnR) was cloned as a 1.5-kb BamHI-PvuII fragment in Escherichia coli (Ec), and shown to confer Th resistance when introduced into S. lividans TK24. The tsnR-containing DNA fragment was used as a probe to isolate clones from cosmid libraries of DNA in the Ec cosmid vector SuperCos, and pOJ446 (an Ec/streptomycete) cosmid vector. Sequence and genetic analysis of the DNA flanking the tsnR indicates that the Sl tsnR is not closely linked to biosynthetic genes. Instead it is located within a cluster of ribosomal protein operons.

Fatty acid composition of blood lipids in Chinese children consuming high erucic acid rapeseed oil

The fatty acid patterns of oils, blood plasma and erythrocyte lipids from 28 children in the Shaanxi province of the People's Republic of China were determined by capillary gas liquid chromatography. The main source of fat in this region is rapeseed oil. The analysis of locally available rapeseed oil shows a high erucic acid content (mean 43.83%, range 33.91-50.48%). According to protocol data, about 3% of the daily nutrient energy is provided by erucic acid. Despite a low fat intake in Chinese children, the composition of the fatty acids of the fractions analyzed showed normal patterns. However, erucic acid was found in all fractions analyzed. Data on erucic acid in human tissue are scarce. Although there are no indications of erucic acid toxicity in man, it is known to cause cardiac lipidosis and necrosis in rats. The question remains open if erucic acid aggravates selenium deficiency symptoms which are known to be associated with Keshan disease, an endemic cardiomyopathy.

[Clinical effect and laboratory observation of ofloxacin in the treatment of typhoid fever, bacillary dysentery and gonorrhea]

Ofloxacin was used in the treatment of 20 cases of typhoid fever, 32 cases of bacillary dysentery and 50 cases of gonococcal infection. Altogether 102 cases were treated, 53 being male and 49 female. The daily dosage was 400 mg to 600 mg, divided into two times. The result showed that the clinical effective rate for typhoid fever, bacillary dysentery and gonococcal infections was 100%, 97% and 94% respectively, while the bacterial eradication rate was 100%, 100% and 94% respectively. the bacterial eradication rate was 100%, 97% and 94% respectively. The side effects were mild in degree. The authors are of the opinion that since ofloxacin can be administered orally with only two times a day, its absorption is nearly complete and the cure rate is high, it should be considered as the drug of choice in the treatment of typhoid fever, bacillary dysentery and gonorrhea, especially in the drug resistant cases. It is suggested that this drug be used more widely.

[Establishment of a human pulmonary adenocarcinoma cell line Lu-YePa and its biological characteristics]

This paper presents the establishment of a human pulmonary adenocarcinoma cell line Lu-YePa and its biological characteristics. The primary cells of Lu-YePa cell line were derived from a twenty six year old patient with poorly differentiated adenocarcinoma of the lung. After 36 days' culture, transfer was made and the cells proliferated steadily and rapidly afterwards. The doubling time was 34.6 hours. Mitotic index reached 49.5% on day 5. Chromosome number was subtriploid with the mode of 62. The large submetacentric marker chromosome was presented in 68% of cells. PAS positive granules were found in the cytoplasm. The study of concanavalin A condensation, electron microscopic observation, heterotransplantation and plating efficiency indicates that Lu-YePa cells are concordant with the human pulmonary adenocarcinoma cells in morphology and biological behavior.