[Distribution, Sources, and Ecological Risk Evaluation of Heavy Metals in Surface Sediments of Taihu Lake].

For the surface sediment samples of Taihu Lake in 2010, the eight physicochemical indices of pH, temperature, Eh, water content, porosity, grain size, total phosphorus, and Loss-on-ignition were measured and analyzed, along with the contents of nine heavy metals:Cu, Zn, Ni, Cr, Pb, Ba, Mn, Co, and V. The order of magnitudes of heavy metal content of surface sediments in Taihu Lake was:Mn>Ba>Zn>Cr>V>Ni>Pb>Cu>Co. This suggested that the contents of the nine heavy metals were beyond the background value, which had a close connection to the geology of the Taihu Lake Basin and were influenced by human activity to varying degrees. The clustering analysis and the spatial distribution of the heavy metals revealed that the concentrations of heavy metals in the North and South Taihu Lake sections decreased from the lake shore to the lake center, the concentrations of heavy metals in the West Taihu Lake section increased from the lake shore to the lake center, and the distribution of heavy metals in the center of the lake remained relatively uniform. According to the correlation study, the metal elements were positively correlated with one another to varying degrees, indicating that they originate from the same source of pollution. According to the PCA and PMF analyses, there were some different sources of heavy metals in Taihu Lake, in which the transportation and industrial complex source were the most important sources, the diagenesis was the second major source, and agriculture was the third major source. Furthermore, the heavy metal pollution was evaluated using the geoaccumulation and the potential ecological risk indices. This offers a solid theoretical backing for the future management of heavy metal pollution in Taihu Lake.

[Epidemiological study of severe sepsis in a newborn intensive care unit].

OBJECTIVES: To determine the incidence and outcome of severe sepsis in Newborn Intensive Care Unit (NICU) and to characterize their demographics and infection pattern. METHODS: Characteristics of 243 newborns admitted to NICU from June 1st, 2006 to May 31st, 2007 were retrospectively analyzed. RESULTS: Analysis of data derived from 243 newborns admitted to NICU over an 1-year period with 48 (19.8%) cases diagnosed as severe sepsis, and 70.8% of them were males. The median age of severe sepsis patients was 2 (1-6 ) days. In 56.3% of the patients bacteria were isolated, and E. coli was the predominant microbe. PRISM score and mortality rate were higher in those with severe sepsis, while their Apgar score was lower than other cases. The overall hospital mortality of severe sepsis was 45.8%. Risk factors for hospital mortality included higher PRISM score, severe organ dysfunction, circulatory system dysfunction, and hematological or central nervous system dysfunction. CONCLUSIONS: This study shows that severe sepsis is a common, frequently fatal morbid condition in critical ill newborns in NICU, showing similar disease pattern with other investigations. Further multiple-center investigations are helpful to prevent, control and salvage critically ill children suffering from severe sepsis.

[Influence of Hydraulic Retention Time on the Treatment of Polluted River Water by an Activated Carbon Rotating Biological Contactor].

The study combined activated carbon with a rotating biological contactor. The activated carbon adsorption experiments were conducted and the biofilm was formed by using the river water directly. The effects of different hydraulic retention times on the removal of NH4+-N, TP, and permanganate index and on the biofilm properties were investigated at the optimum rotational speed of the disc. Experimental results are as follows. The Freundlich isotherm showed that activated carbon had better adsorption properties for NH4+-N, TP, and permanganate index in water.When the disk speed was 3 r·min-1, the removal efficiency was the best, and the removal rates of NH4+-N, TP and permanganate index were the best at 86.05%, 81.28%, and 77.09%, respectively. In addition, there was a significant linear correlation between the hydraulic retention time and the removal of NH4+-N and TP (R2>0.9), respectively. The removal rates of NH4+-N and TP at different hydraulic retention times were significantly different (P<0.05), but the permanganate index was not (P>0.05).Hydraulic retention time had effects on the biofilm activity, protein and polysaccharide contents,and the three-dimensional fluorescence peaks of S-EPS, LB-EPS, and TB-EPS of the biofilm.

Toosendanin inhibits adipogenesis by activating Wnt/ß-catenin signaling.

Toosendanin (TSN), a triterpenoid extracted from Melia toosendan, has been reported to possess anti-oxidant, anti-inflammatory, anti-allergic, and anti-arthritic activities. However, its anti-adipogenic effect remains unknown. Here, we found that TSN dose-dependently attenuated lipid accumulation in preadipocytes 3T3-L1 as evidenced by Oil Red O staining. TSN also significantly downregulated mRNA and protein levels of adipocytokines (adiponectin and leptin), CCAAT/enhancer binding proteins α (C/EBP-α), peroxisome proliferator-activated receptor γ (PPAR-γ), fatty acid synthase, and acetyl-CoA carboxylase in adipocytes. To understand the mechanism, we observed that TSN effectively activated Wnt/ß-catenin pathway, in which TSN increased low density lipoprotein receptor related protein 6, disheveled 2, ß-catenin, and cyclin D1 expression levels, while it inactivated glycogen synthase kinase 3ß by enhancing its phosphorylation. Moreover, TSN reduced weight of gonadal white fat and serum triacylglycerol (TAG) content in high-fat diet (HFD)-fed mice. Interestingly, the in vivo studies also demonstrated that TSN promoted the expression of ß-catenin, but accordingly repressed C/EBP-α and PPAR-γ expression in HFD-induced mice. Overall, TSN is capable of inhibiting the lipogenesis of adipocytes by activating the Wnt/ß-catenin pathway, suggesting potential application of TSN as a natural anti-obesity agent.

Effects of lanthanum(III) on nitrogen metabolism of soybean seedlings under elevated UV-B radiation.

The hydroponic culture experiments of soybean bean seedlings were conducted to investigate the effect of lanthanum (La) on nitrogen metabolism under two different levels of elevated UV-B radiation (UV-B, 280-320 nm). The whole process of nitrogen metabolism involves uptake and transport of nitrate, nitrate assimilation, ammonium assimilation, amino acid biosynthesis, and protein synthesis. Compared with the control, UV-B radiation with the intensity of low level 0.15 W/m2 and high level 0.45 W/m2 significantly affected the whole nitrogen metabolism in soybean seedlings (p < 0.05). It restricted uptake and transport of NO3(-), inhibited activity of some key nitrogen-metabolism-related enzymes, such as: nitrate reductase (NR) to the nitrate reduction, glutamine systhetase (GS) and glutamine synthase (GOGAT) to the ammonia assimilation, while it increased the content of free amino acids and decreased that of soluble protein as well. The damage effect of high level of UV-B radiation on nitrogen metabolism was greater than that of low level. And UV-B radiation promoted the activity of the anti-adversity enzyme glutamate dehydrogenase (GDH), which reduced the toxicity of excess ammonia in plant. After pretreatment with the optimum concentration of La (20 mg/L), La could increase the activity of NR, GS, GOGAT, and GDH, and ammonia assimilation, but decrease nitrate and ammonia accumulation. In conclusion, La could relieve the damage effect of UV-B radiation on plant by regulating nitrogen metabolism process, and its alleviating effect under low level was better than that under the high one.

Reversal of the Apoptotic Resistance of Non-Small-Cell Lung Carcinoma towards TRAIL by Natural Product Toosendanin.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively triggers cancer cell death via its association with death receptors on the cell membrane, but exerts negligible side effects on normal cells. However, some non-small-cell lung carcinoma (NSCLC) patients exhibited resistance to TRAIL treatment in clinical trials, and the mechanism varies. In this study, we described for the first time that toosendanin (TSN), a triterpenoid derivative used in Chinese medicine for pain management, could significantly sensitize human primary NSCLC cells or NSCLC cell lines to TRAIL-mediated apoptosis both in vitro and in vivo, while showing low toxicity against human primary cells or tissues. The underlying apoptotic mechanisms involved upregulation of death receptor 5 (DR5) and CCAAT/enhancer binding protein homologous protein, which is related to the endoplasmic reticulum stress response, and is further associated with reactive oxygen species generation and Ca2+ accumulation. Surprisingly, TSN also induced autophagy in NSCLC cells, which recruited membrane DR5, and subsequently antagonized the apoptosis-sensitizing effect of TSN. Taken together, TSN can be used to sensitize tumors and the combination of TRAIL and TSN may represent a useful strategy for NSCLC therapy; moreover, autophagy serves as an important drug resistance mechanism for TSN.

Two Schiff-base fluorescent sensors for selective sensing of aluminum (III): Experimental and computational studies.

Two Schiff-base fluorescent sensors have been synthesized, which both can act as fluorescent probes for Al(3+), upon addition of Al(3+), they exhibit a large fluorescence enhancement which might be attributed to the formation of 1:1 ligand-Al complexes which inhibit photoinduced electron transfer (PET) progress, and that the proposed binding modes of the sensors and Al(3+) are identified by theoretical calculations.

[Enrichment and Characterization of A Denitrifying Bacteria Consortium from Lihe River's Sediment].

A denitrifying bacteria consortium was enriched from LiHe River's sediment, the dynamics of total nitrogen (TN), nitrate (NO3- -N), nitrite (NO2- -N), ammonium (NH4+ -N) and COD at different enrichment cultivation stages were studied, and the total volume, the releasing rates and the composition of gas released during the denitrification process were analyzed. The full-length 16S rDNA clone library was constructed, enclosing the diversity of the denitrifying bacteria consortium. The results showed, in the enrichment phase 4, under the load of TN 330 mg x L(-1), the best nitrogen removal effect was obtained, which the TN and NO3- -N removal rates reached 90.9% and 100% within 9 hours, respectively. The accumulation amounts of NO2- -N and NH4+ -N were merely 3.39 mg x L(-1) and 16.64 mg x L(-1). And the COD removal rate was 85%. The process released 260 mL of the compound gas, in which the main ingredient was N2 associated with a small quantity of CH4 and CO2. The denitrifying bacteria consortium consisted of the family Pseudomonadaceae and the family Rhodocyclaceae, belonging to Proteobacteria phylum, in which the OUT abundances were 57.8% and 31.6%, respectively. The family Pseudomonadaceae was the predominant group.

[Clinical significance of oral fluconazole prophylaxis against invasive fungal infection in preterm neonates with peripherally inserted central catheters].

OBJECTIVE: With the widespread application of peripherally inserted central catheters (PICC) in neonatal intensive care unit (NICU), the incidence of invasive fungal infections increased significantly than ever. The present study aimed to explore the clinical significance of oral fluconazole in premature infants with gestational age ≤ 32 weeks and/or birth weight ≤ 1500 grams who had catheter insertions. METHOD: This study enrolled 118 infants admitted between January 2006 and December 2007 who did not receive fluconazole prophylaxis (control group) and 106 infants admitted between January 2008 and June 2009 who received oral fluconazole prophylaxis (prophylaxis group). Statistical analyses were performed by using SPSS 11.5 software. The clinical characteristics and the risk factors for invasive fungal infection between the two groups were compared. Liver functions (alanine transaminase, ALT and direct bilirubin) were monitored to evaluate the safety of fluconazole prophylaxis. RESULT: Except for the proportion of infants born via vaginal delivery in the control group (56/118, 47.5%) was significantly lower than that in prophylaxis group (69/106, 65.1%, P = 0.007), there were no significant significant differences in the demographics and other baseline clinical characteristics between the two groups. There were no significant differences in the risk factors for invasive fungal infection between the two groups either. Nine infants developed invasive fungal infection in control group (7.6%), while no invasive fungal infection was found in prophylaxis group (0%, P = 0.01). Compared to infants in control group, those in prophylaxis group showed no significant changes in alanine transaminase ALT and direct bilirubin levels at 2 weeks and 4 weeks after fluconazole prophylaxis: the incidences of abnormal ALT and direct bilirubin levels were 8.5% (10/118) and 6.8% (8/118) in control group compared to 11.3% (12/106) and 8.5% (9/106) in prophylaxis group after 2 weeks (P = 0.47 and 0.63); the incidences of abnormal ALT and direct bilirubin levels were 3.4% (4/118) and 3.4% (4/118) in control group compared to 5.7% (6/106) and 8.5% (9/106) in prophylaxis group after 4 weeks (P = 0.62 and 0.15). CONCLUSION: For infants with PICC insertions and gestational ages at birth ≤ 32 weeks and/or low birth weight ≤ 1500 grams, oral fluconazole is effective to prevent invasive fungal infection. Oral fluconazole in premature infants neither affected the liver function, nor increased the incidence of cholestasis.