Avulsion fracture of the anterior superior iliac crest following autograft for anterior lumbar fusion: case report and literature review.

Avulsion fracture of the anterior superior iliac crest (ASIC) following autogenous bone grafting for anterior lumbar fusion (ALF) is an extremely rare complication. We describe a very rare case of avulsion fracture of the ASIC following autograft for ALF in a revision surgery for treating lumbar tuberculosis. A 68-year-old woman with lumbar tuberculosis underwent posterior debridement and posterior iliac crest bone graft fusion; however, her lumbar tuberculosis recurred 9 months after surgery. She then underwent a lumbar revision surgery, including removal of the posterior instrumentation and debridement, followed by anterior L2 corpectomy, debridement, anterior left iliac crest bone graft fusion, and internal fixation. When walking for the first time on postoperative day 3, she experienced a sharp, sudden-onset pain in the anterior iliac crest harvest area. X-ray revealed an avulsion fracture of the ASIC. Considering her failure to respond to conservative treatment for one week and large displacement of the fracture ends, an open reduction and internal fixation surgery was scheduled. Her pain symptoms were significantly relieved after the operation. Although rare, fracture of the ASIC following autograft for ALF should not be ignored. Fracture of the ASIC is usually treated conservatively. Additional surgical treatment is required only when intractable pain fails to respond to conservative treatment or when there is a large displacement of fracture ends that are not expected to heal spontaneously.

[Application of "Sancai principle" for needle-knife treatment of bi syndrome of neck region].

Under the guidance of the "Sancai principle", based on the understanding of the etiology and pathogenesis of the imbalance of muscles and bones in bi syndrome of neck region, holistic treatment should be used. The needle-knife release therapy is applied at corresponding acupoints in the three parts i.e. head, neck and back including Tiancai points (Naohu [GV 17] and Naokong [GB 19]), Rencai points (neck Jiaji [EX-B 2]), and Dicai points (Dazhui [GV 14], Quyuan [SI 13] and Tianzong [SI 11]). According to the layers of the lesion's meridians and muscles, the needle-knife is inserted into skin, muscle and bone to relax the tendons and treat bone disorders, and restore the normal mechanical balance of neck.

Actinomycetes Rhodococcus ruber CGMCC 17550 degrades neonicotinoid insecticide nitenpyram via a novel hydroxylation pathway and remediates nitenpyram in surface water.

Neonicotinoid insecticides are neurotoxicants that cause serious environmental pollution and ecosystem risks. In the present study, a nitenpyram-degrading bacterium, Rhodococcus ruber CGMCC 17550, was isolated from a nitenpyram production sewage treatment tank. Liquid chromatography-mass spectrometry analysis revealed R. ruber degraded nitenpyram via a novel hydroxylation pathway to form three different metabolites, one of which was confirmed to hydroxylate nitenpyram at the C3 site of the 6-chlorpyridine cycle by nuclear magnetic resonance analysis. The nitenpyram degradation rate increased as the biomass of resting R. ruber CGMCC 17550 cells increased, reaching 98.37% at an OD600 of 9 in transformation broth containing 100 mg L-1 nitenpyram after 72 h of incubation. Nitenpyram degradation by R. ruber CGMCC 17550 was insensitive to dissolved oxygen levels. Use of glucose, fructose and pyruvate as co-substrates slightly increased nitenpyram degradation. The cytochrome P450 inhibitor 1-aminobenzotriazole strongly inhibited nitenpyram degradation, indicating that P450 enzymes may mediate nitenpyram hydroxylation. Inoculation of R. ruber CGMCC 17550 enhanced nitenpyram degradation in surface water. Additionally, R. ruber cells immobilized by calcium-alginate remediated 87.11% of 100 mg L-1 NIT in 8 d. Genome sequencing analysis confirmed that R. ruber CGMCC 17550 has metabolic diversity and abundant KEGG genes involved in xenobiotics biodegradation and metabolism. These findings demonstrate that R. ruber CGMCC 17550 is capable of unique biodegradation of nitenpyram via the hydroxylation pathway and is a promising bacterium for bioremediation of contaminants.

Bioinformatics of a Novel Nitrile Hydratase Gene Cluster of the N2-Fixing Bacterium Microvirga flocculans CGMCC 1.16731 and Characterization of the Enzyme.

Microvirga flocculans CGMCC 1.16731 can degrade many cyano group-containing neonicotinoid insecticides. Here, its genome was sequenced, and a novel nitrile hydratase gene cluster was discovered in a plasmid. The NHase gene cluster (pnhF) has gene structure ß-subunit 1, α-subunit, and ß-subunit 2, which is different from previously reported NHase gene structures. Phylogenetic analysis of α-subunits indicated that NHases containing the three subunit (ß1αß2) structure are independent from NHases containing two subunits (αß). pnhF was successfully expressed in Escherichia coli, and the purified PnhF could convert the nitrile-containing insecticide flonicamid to N-(4-trifluoromethylnicotinoyl)glycinamide. The enzymatic properties of PnhF were investigated using flonicamid as a substrate. Homology models revealed that amino acid residue ß1-Glu56 may strongly affect the catalytic activity of PnhF. This study expands our understanding of the structures and functions of NHases and the enzymatic mechanism of the environmental fate of flonicamid.

Sulfoxaflor Degraded by Aminobacter sp. CGMCC 1.17253 through Hydration Pathway Mediated by Nitrile Hydratase.

Sulfoxaflor, a sulfoximine insecticide, could efficiently control many insect pests of sap-feeding. Microbial degradation of sulfoxaflor and the enzymatic mechanism involved have not been studied to date. A bacterial isolate JW2 that transforms sulfoxaflor to X11719474 was isolated and identified as Aminobacter sp. CGMCC 1.17253. Both the recombinant Escherichia coli strain harboring the Aminobacter sp. CGMCC 1.17253 nitrile hydratase (NHase) gene and the pure NHase acquired sulfoxaflor-degrading ability. Aminobacter sp. CGMCC 1.17253 NHase is a typical cobalt-containing NHase content of subunit α, subunit ß, and an accessory protein, and the three-dimensional homology model of NHase was built. Substrate specificity tests showed that NHase catalyzed the conversion of acetamiprid, thiacloprid, indolyl-3-acetonitrile, 3-cyanopyridine, and benzonitrile into their corresponding amides, indicating its broad substrate specificity. This is the first report of the pure bacteria degradation of the sulfoxaflor residual in the environment and reveals the enzymatic mechanism mediated by Aminobacter sp. CGMCC 1.17253.

The impact of renal function on efficacy and safety of new oral anticoagulant in atrial fibrillation patients: A systemic review and meta-analysis.

BACKGROUND AND OBJECTIVES: This meta-analysis was to investigate the efficacy and safety of new oral anticoagulant (NOAC) in atrial fibrillation (AF) patients with renal function insufficiency, and to explore whether renal decline occurs in AF patients with NOAC and its impact on outcomes. METHODS AND RESULTS: In AF patients with mild renal insufficiency, the NOAC was associated with significantly lower rates of stroke (odds ratio [OR], 0.78; 95% confidence interval [CI], 0.67-0.91; P < .05). Lower rates of bleeding were significantly observed in NOAC group (OR, 0.85; 95% CI, 0.75-0.97; P < .05). In AF patients with moderate renal impairment, similar results were revealed (OR for stroke or systemic embolism, 0.80; 95% CI, 0.67-0.95, P < .05; OR for major bleeding, 0.78; 95% CI, 0.59-1.03; P = .07). During the follow-up, pooled data revealed that NOAC showed a less renal toxicity, but the difference did not reach statistical significance (creatinine clearance decline: -0.12 mL/min [-0.84, 0.61 mL/min]). We have revealed that the NOACs were associated with significantly lower rates of stroke or systemic embolism (hazard ratio [HR], 0.66; 95% CI, 0.42-0.89; P < .05) and lower rates of bleeding (HR, 0.93; 95% CI, 0.70-1.16; P = .153) in AF patients with worsening renal function. CONCLUSIONS: NOAC may have the potentiality to be at least as effective as warfarin and may equal safety outcomes in AF patients with renal impairment. Renal decline during therapeutics may be less likely happened in NOAC than warfarin dose. NOAC may reveal good efficacy and safety outcomes in these scenarios. Further detailed research is needed to gain more clear profile on this new anticoagulant.

Biodegradation of the Insecticide Flonicamid by Alcaligenes faecalis CGMCC 17553 via Hydrolysis and Hydration Pathways Mediated by Nitrilase.

Flonicamid (N-cyanomethyl-4-trifluoromethylnicotinamide, FLO), a novel selective systemic pyridinecarboxamide insecticide, effectively controls hemipterous pests. However, microbial degradation of flonicamid, along with the enzymatic mechanism, has not been studied. Here, bacterial isolate PG13, which converts flonicamid into 4-(trifluoromethyl)nicotinol glycine (TFNG) and N-(4-trifluoromethylnicotinoyl)glycinamide (TFNG-AM), was isolated and identified as Alcaligenes faecalis CGMCC 17553. The genome of CGMCC 17553 contained five nitrilases but no nitrile hydratase, and recombinant Escherichia coli strains harboring CGMCC 17553 nitrilase gene nitA or nitD acquired the ability to degrade flonicamid. Purified NitA catalyzed flonicamid into both TFNG and TFNG-AM, indicating dual functionality, while NitD could only produce TFNG-AM. Three-dimensional homology modeling revealed that aromatic amino acid residues in the catalytic pocket affected nitrilase activity. These findings further our understanding of the enzymatic mechanism of flonicamid metabolism in the environment and may help develop a potential bioremediation agent for the elimination of flonicamid contamination.

[Current status and perspective on research against Fusarium head blight in wheat].

Wheat is one of the most important food crops in China and worldwide. Wheat production is facing the stresses of different diseases including Fusarium head blight (FHB) which is more and more serious recently and leading to highly concerns. Unremitting efforts have been made on Fusarium head blight resistance breeding and comprehensive control technology development. Rapid progress has been achieved on discovering of resistant genetic resources, mapping of resistant QTL/genes, resistant QTL/genes cloning, gene functional research and molecular breeding. In this review, we summarize the current status of the research against FHB in wheat and discuss the issues of FHB resistance investigation to date. We also suggest emphasizing on gene cloning, developing more powerful functional markers, using haplotype-assisted selection (HAS) and marker-set-assisted selection (MSAS) for further deep FHB resistance study and breeding.

RETINAL MICROVASCULATURE ALTERATION IN ACTIVE THYROID-ASSOCIATED OPHTHALMOPATHY.

OBJECTIVE: It is uncertain whether there is an increased retinal vessel density in patients with thyroid-associated ophthalmology (TAO), or if ocular hemodynamic changes are associated with their vision. Many techniques have been applied to analyze ocular hemodynamic changes in TAO patients; however, they suffer from limitations. Optical coherence tomography angiography (OCTA) is more sensitive to hemodynamic changes. We performed OCTA to determine whether there is an increased retinal vessel density in TAO patients, and investigate associations with their vision. METHODS: Twenty TAO patients (right eye) and 20 normal controls (right eye) were recruited for the study. Three-dimensional OCTA images were generated with 6 × 6-mm angiographic OCT scans of the superficial retinal layer (SRL) and deeper retinal layer (DRL) of the macular retina for each eye. We calculated the microvascular (MIR) and macrovascular (MAR) densities and compared MIR, MAR, and total MIR (TMI) density in the healthy control and TAO groups separately. We used the annular partition (C1-C6) and quadrant partition method to analyze retinal vessel density alterations. Correlation analyses were used to examine the association of MIR density and visual acuity. RESULTS: In the SRL, STMI (superficial TMI) and SMIR (superficial MIR) density increased in the macular area of TAO patients ( P<.05). For the DRL, the density of DMIR (deeper MIR) increased in macular area only ( P<.05). However, with the annular partition method, TAO patients showed significantly increased SMIR density in the C1 and C2 regions ( P<.05), and increased DMIR density only in the C1 region ( P<.05). In the SRL, the correlation coefficient of the STMI/SMIR density in the TAO group was -0.538 ( r = -0.538, P = .032), and visual acuity was -0.624 ( r = -0.624, P = .010). CONCLUSION: OCTA findings suggest that active TAO patients present with an increased retinal MIR density. Moreover, increased macular STMI and SMIR density might affect visual acuity. ABBREVIATIONS: CDI = color Doppler imaging; DMIR = deeper MIR; DRL = deeper retinal layer; EDV = end diastolic velocity; FAZ = foveal avascular zone; GO = Graves ophthalmopathy; MAR = macrovascular; MIR = microvascular; OCT = optical coherence tomography; OCTA = optical coherence tomography angiography; RI = resistance index; ROC = receiver operating characteristic; SMIR = superficial MIR; SOV = superior ophthalmic vein; SRL = superficial retinal layer; SSADA = split-spectrum amplitude-decor-relation angiography; STMI = superficial TMI; TAO = thyroid-associated ophthalmology; TMI = total MIR.

The Plant Growth-Promoting Rhizobacterium Variovorax boronicumulans CGMCC 4969 Regulates the Level of Indole-3-Acetic Acid Synthesized from Indole-3-Acetonitrile.

Variovorax is a metabolically diverse genus of plant growth-promoting rhizobacteria (PGPR) that engages in mutually beneficial interactions between plants and microbes. Unlike most PGPR, Variovorax cannot synthesize the phytohormone indole-3-acetic acid (IAA) via tryptophan. However, we found that Variovorax boronicumulans strain CGMCC 4969 can produce IAA using indole-3-acetonitrile (IAN) as the precursor. Thus, in the present study, the IAA synthesis mechanism of V. boronicumulans CGMCC 4969 was investigated. V. boronicumulans CGMCC 4969 metabolized IAN to IAA through both a nitrilase-dependent pathway and a nitrile hydratase (NHase) and amidase-dependent pathway. Cobalt enhanced the metabolic flux via the NHase/amidase, by which IAN was rapidly converted to indole-3-acetamide (IAM) and in turn to IAA. IAN stimulated metabolic flux via the nitrilase, by which IAN was rapidly converted to IAA. Subsequently, the IAA was degraded. V. boronicumulans CGMCC 4969 can use IAN as the sole carbon and nitrogen source for growth. Genome sequencing confirmed the IAA synthesis pathways. Gene cloning and overexpression in Escherichia coli indicated that NitA has nitrilase activity and IamA has amidase activity to respectively transform IAN and IAM to IAA. Interestingly, NitA showed a close genetic relationship with the nitrilase of the phytopathogen Pseudomonas syringae Quantitative PCR analysis indicated that the NHase/amidase system is constitutively expressed, whereas the nitrilase is inducible. The present study helps our understanding of the versatile functions of Variovorax nitrile-converting enzymes that mediate IAA synthesis and the interactions between plants and these bacteria.IMPORTANCE We demonstrated that Variovorax boronicumulans CGMCC 4969 has two enzymatic systems-nitrilase and nitrile hydratase/amidase-that convert indole-3-acetonitrile (IAN) to the important plant hormone indole-3-acetic acid (IAA). The two IAA synthesis systems have very different regulatory mechanisms, affecting the IAA synthesis rate and duration. The nitrilase was induced by IAN, which was rapidly converted to IAA; subsequently, IAA was rapidly consumed for cell growth. The nitrile hydratase (NHase) and amidase system was constitutively expressed and slowly but continuously synthesized IAA. In addition to synthesizing IAA from IAN, CGMCC 4969 has a rapid IAA degradation system, which would be helpful for a host plant to eliminate redundant IAA. This study indicates that the plant growth-promoting rhizobacterium V. boronicumulans CGMCC 4969 has the potential to be used by host plants to regulate the IAA level.

[Depressant effect of Lithium on apoptosis of nerve cells of adult rats after spinal cord injury].

OBJECTIVE: To study whether lithium agent produces neuroprotective effect by inhibiting the nerve cell apoptosis of rats after spinal cord injury. METHODS: Forty-two male SD rats weighing 200 to 250 g were randomly divided into 3 groups: blank control group(n=6) without surgery, normal saline(NS) group(n=18) with intraperitoneal injection of NS (40 mg/kg); and Lithium chloride (Licl) group (n=18) with intraperitoneal injection of Licl (40 mg/kg). After Allen method modeling, Licl group started intraperitoneal injection of Licl solution (40 mg·kg⁻¹·d⁻¹) within 15 min after operation to the second week. NS group, during the same interval, was injected with a same amount of NS. Postoperative 3, 7, 14 d, BBB scores in each group were measured;the expression of Bcl-2 and Bax protein were observed by immunohistochemisty staining;TUNEL staining was used to observe the nerve cell apoptosis. RESULTS: The BBB scores in blank control group were 21. Postoperative 7, 14 d, BBB scores of Licl group were higher than that of NS group(P<0.05). As for the Bcl-2 protein expression, black control group has a level of 0.081±0.003;7 d and 14 d postoperatively, the level in Licl group was 0.151±0.003, 0.163±0.003 and in NS group, 0.143±0.003, 0.154±0.002, respectively. Licl group showed significantly increased Bcl-2 protein expression(P<0.05). As for the Bax protein expression, black control group showed a level of 0.071±0.003; 7 d and 14 d postoperatively, the level in Licl group was 0.121±0.002, 0.106±0.002 and in NS group was 0.126±0.001, 0.120±0.002, respectively. The Bax protein expression is significantly inhibited in the Licl group(P<0.05). In nerve cell apoptosis by TUNEL staining, the positive cells were fewer in the black control group with apoptosis index (AI) of 1.98±0.19;while 7d and 14d postoperatively, the AI of Licl group was 13.12±0.69, 4.29±1.00 and of NS group, 18.26±0.87, 5.48±0.70, respectively. Licl group showed significant inhibition of the cell apoptosis(P<0.05). CONCLUSIONS: Licl can promote the Bcl-2 protein expression and inhibit the Bax proteins expression in nerve cells of rat after SCI, thereby playing a role in the inhibition of nerve cell apoptosis. This may be one of the mechanisms that Licl can promote the recovery of motor function of rats after SCI.

[Meta analysis of clinical effects between intramedullary nail and volar plate internal fixation for distal radius fractures].

OBJECTIVE: To evaluate curative effects of intramedullary nail and volar plate internal fixation for distal radius fractures. METHODS: The studies concerning about randomized controlled trial of intramedullary nail and volar plate internal fixation for distal radius fractures from create database to May, 2016 were searched from PubMed, Cochrane Library, Web of Science, CNKI, Wan Fang data and VIP. Information was screen and taken out according to inclusion and exclusion criteria, quality of literature was evaluated according to Cochrane Handbook evaluating system. Meta analysis was performed by RevMan 5.2 software. Postoperative grip strength, clinical effects(results of flexion and extension, pronation, supination, deflection of ulnar and radialis) , imaging evaluation (ulnar variance, radial height, volar tilting angle and radial inclination) and the incidence of postoperative complications were analyzed. RESULTS: Totally 6 RCT including 370 patients were chosen. According to the Meta analysis, there were no statistical differences in extension[MD=5.63, 95%CI(-7.01, 18.27), P=0.38], flexion[MD=3.10, 95%CI(-0.67, 6.86), P=0.11], pronation[MD=2.58, 95%CI(-0.49, 5.65), P=0.10], supination[MD=0.82, 95%CI(-1.89, 3.54), P=0.55], radial deviation[MD=-5.16, 95%CI(-14.42, 4.11), P=0.28], ulnar deviation[MD=0.19, 95%CI(-2.39, 2.77), P=0.88], ulnar variance[MD=-0.01, 95%CI(-0.43, 0.42), P=0.97], ulnar inclination[MD=-0.31, 95%CI(-1.37, 0.73), P=0.56], radial height[MD=-0.27, 95%CI(-0.98, 0.44), P=0.45], radial inclination[MD=0.29, 95%CI(-0.41, 0.99), P=0.42] and the incidence of postoperative complications[RR=0.71, 95%CI(0.46, 1.09), P=0.12] between intramedullary nail and volar plate internal fixation. CONCLUSIONS: Compared with volar plate internal fixation, intramedullary nail has the same effect in grip strength, clinical effect, but could not reduce the occurrence of postoperative complications. However, a large number of prospective randomized controlled study should be carried out to prove clinical effect of intramedullary nail for distal radius fractures.

Regulation of Hydroxylation and Nitroreduction Pathways during Metabolism of the Neonicotinoid Insecticide Imidacloprid by Pseudomonas putida.

Imidacloprid (IMI) is mainly metabolized via nitroreduction and hydroxylation pathways, which produce different metabolites that are toxic to mammals and insects. However, regulation of IMI metabolic flux between nitroreduction and hydroxylation pathways is still unclear. In this study, Pseudomonas putida was found to metabolize IMI to 5-hydroxy and nitroso IMI and was therefore used for investigating the regulation of IMI metabolic flux. The cell growth time, cosubstrate, dissolved oxygen concentration, and pH showed significant effect on IMI degradation and nitroso and 5-hydroxy IMI formation. Gene cloning and overexpression in Escherichia coli proved that P. putida KT2440 aldehyde oxidase mediated IMI nitroreduction to nitroso IMI, while cytochrome P450 monooxygenase (CYP) failed to improve IMI hydroxylation. Moreover, E. coli cells without CYP could hydroxylate IMI, demonstrating the role of a non-CYP enzyme in IMI hydroxylation. Thus, the present study helps to further understand the environmental fate of IMI and its underlying mechanism.

Hepatitis B surface antigen quantification at hepatitis B e antigen seroconversion predicts virological relapse after the cessation of entecavir treatment in hepatitis B e antigen-positive patients.

OBJECTIVES: To assess off-treatment virological relapse rates and to determine the role of hepatitis B surface antigen (HBsAg) quantification in predicting virological relapse after stopping entecavir (ETV) treatment in patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB). METHODS: One hundred and twelve CHB patients for whom ETV was stopped in accordance with the Asian Pacific Association for the Study of the Liver guidelines stopping rules were enrolled. Patient HBsAg and HBV DNA levels were monitored every 4-12 weeks during ETV treatment and after ETV cessation. Post-treatment virological relapse was defined as a serum HBV DNA level of >10 000 copies/ml after stopping ETV treatment. RESULTS: The virological relapse rate at 52 weeks after stopping ETV was 48.2%. The post-treatment virological relapse rate was significantly higher in patients aged >50 years than in those aged <50 years (p < 0.001), and the virological relapse rate was significantly lower in patients with an HBsAg level <2.0 log10 IU /ml than in those with a level ≥ 2.0 log10 IU /ml at ETV cessation (p = 0.005). An HBsAg level of 2.5 log10 IU/ml at HBeAg seroconversion was the optimal cut-off value for predicting post-treatment virological relapse (p < 0.001). In those aged <50 years and with HBsAg ≤ 2.5 log10 IU/ml at HBeAg seroconversion, the relapse rate was only 5%. In patients with HBsAg ≤ 2.5 log10 IU/ml at HBeAg seroconversion, 52.4% achieved HBsAg levels ≤ 2.0 log10 IU/ml at ETV cessation, while in those with HBsAg >2.5 log10 IU/ml at HBeAg seroconversion, only 4.4% achieved this criterion. CONCLUSIONS: HBsAg levels can help guide the timing of cessation of ETV treatment. HBsAg levels of 2.5 log10 IU/ml at HBeAg seroconversion may be a useful marker to predict virological relapse after the cessation of ETV treatment in HBeAg-positive CHB patients.

Tree bark as a biomonitor for the determination of polychlorinated biphenyls and polybrominated diphenyl ethers from Southern Jiangsu, China: levels, distribution, and possible sources.

Tree bark was used as the passive air sampler to evaluate polychlorinated biphenyl (PCB) and polybrominated diphenyl ether (PBDE) pollution and possible sources in Southern Jiangsu. The concentrations of PCBs and Σ7PBDEs were in the range of 0.58-5.19 ng/g dry weight (dw; mean 1.79 ng/g dw) and 17.9-243 pg/g dw (mean 74.7 pg/g dw), respectively. Tri-PCBs were the major PCB homologs, and technical PCB product Ar1242 was identified as the main source. BDE209 concentrations (4.29-456 ng/g dw) were relatively high, indicating that BDE209 pollution was serious in this region. The deca-BDE commercial mixture was the predominant commercial PBDE product used in this region. A good correlation was found between tree bark and polyurethane foam (PUF) disks in Σ6PCB monitoring, suggesting that both of them respond well to the gas-phase PCB monitoring.

Changes of polybrominated diphenyl ethers and polychlorinated biphenyls in surface soils from urban agglomeration of the Yangtze River Delta, in China between 2003 and 2012.

Surface soil samples were collected from urban agglomeration of the Yangtze River Delta (YRD), China in 2003 and 2012, respectively. Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were analyzed to determine if there were any changes in their levels and compositional profiles between the two sampling years. The concentrations of Σ8PBDEs ranged from 0.553 to 13.0 µg kg(-1)(with the mean of 3.31 µg kg(-1)) in the 2003 samples and from 1.01 to 43.2 µg/kg (with the mean of 10.0 µg kg(-1)) in the 2012 samples. The concentrations of Σ32PCBs ranged from 0.301 to 3.29 µg kg(-1)(with the mean of 1.01 µg kg(-1)) in the 2003 samples and from 0.205 to 3.96 µg/kg (with the mean of 0.991 µg kg(-1)) in the 2012 samples. The comparisons between the 2012 and 2003 data showed that PBDEs concentrations increased over the years, but PCB concentrations did not change much. BDE-209 was the major BDE congener in both the 2003 and 2012 samples, indicating that the dominant PBDE mixture production and usage in the YRD had been the commercial deca-BDE mixture. Investigation of the PBDE congener profiles indicated that there had been new input of octa-BDEs in this region in recent years. Little change was found for the pattern of PCBs congener profiles between 2 years' samples. As such, spatial distributions of PBDEs or PCBs in surface soil samples reflected a gradient (from high to low) from the central cities out to rural areas in both the 2003 and 2012 data. In addition, high concentrations of PBDEs were observed in the industrial and residential areas, whereas high concentrations of PCBs were only observed in the industrial areas.

[Levels and possible sources of organochlorine pesticides (OCPs) in camphor (Cinnamomum camphora) tree bark from Southern Jiangsu, China].

Thirty-three camphor tree bark samples were collected from Southern Jiangsu in August 2012. They were analyzed for organochlorine pesticides (OCPs), including hexachlorobenzene (HCB), DDTs (o,p'-DDE, p,p'-DDE, o,p'-DDD, p,p'-DDD, o,p'-DDT and p,p'-DDT), trans-chlordane and cis-chlordane. The concentrations of HCB, sigma6 DDTs and sigma Chlordanes ranged (dw) from 0.31 ng x g(-1) to 1.81 ng x g(-1), 0.40 ng x g(-1) to 17.3 ng x g(-1) and n. d. to 1.03 ng x g(-1), respectively. Due to the high volatility, the spatial distribution of HCB in Southern Jiangsu was uniform. Compared to the other results, the HCB concentration in Southern Jiangsu was lower. The historical usage of technical DDT mixture and the dicofol-type DDT were the major sources of DDTs in southern Jiangsu. The TC/CC ratio is usually used to distinguish between aged and fresh chlordane. According to the ratio of TC/CC, the chlordane in the urban area was derived from the fresh application of technical chlordane, and that in the rural area was attributed to the historical usage.

Occurrence, sources, and ecological risks of PBDEs, PCBs, OCPs, and PAHs in surface sediments of the Yangtze River Delta city cluster, China.

Polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in 25 surface sediments in three cities (Nantong, Wuxi, and Suzhou) in the Yangtze River Delta, eastern China were measured. The mean concentrations were 378, 45.8, 1.98, 4,002 ng/g for PBDEs, OCPs, PCBs, and PAHs, respectively. Their levels in the sediments in the three cities were generally consistent with the city industrialization. PBDEs and OCPs were markedly dominated by deca-BDE (>90 %) and DDTs (>70 %). A principle component analysis of the analytes identified three major factors suggesting different sources of the contaminants in the sediments. PBDEs and the organic carbon in the sediments have common sources from industrial activities; whereas OCPs and PCBs, correlated with the second factor, were mainly from historical sources. The third factor with loadings of PAHs is indicative of various combustion sources. Ecological risk assessment indicated that the potential highest risk is from DDTs, for which 22 sites exceed the effects range low (ERL) values and three sites exceed the effects range median (ERM) value.

A highly selective fluorescent chemosensor for iron ion based on 1H-imidazo [4,5-b] phenazine derivative.

Two kinds of fluorescent sensors (S and S1) for Fe(3+) bearing 1H-Imidazo [4,5-b] phenazine derivatives have been designed and synthesized. Between the two sensors, S showed excellent fluorescent specific selectivity and high sensitivity for Fe(3+) in DMSO solution. The test strip based on S was fabricated, which could act as a convenient and efficient Fe(3+) test kit. The recognition mechanism of the sensor toward Fe(3+) was evaluated by MS, IR and XRD. The detection limit of the sensor S towards Fe(3+) is 4.8×10(-6)M. And other cations, including Hg(2+),Ag(+), Ca(2+), Cu(2+), Co(2+), Ni(2+), Cd(2+), Pb(2+), Zn(2+), Cr(3+), and Mg(2+) had no influence on the probing behavior.

[PUF passive air sampling of polycyclic aromatic hydrocarbons in atmosphere of the Yangtze River Delta, China: spatio-temporal distribution and potential sources].

Atmosphere is regarded to be an important media in the environmental pollution research area. Passive air sampling was one of the effective complementary sampling techniques for the active high volume air sampler in recent decades. A regional scale investigation on the atmospheric polycyclic aromatic hydrocarbons (PAHs) was conducted in the Yangtze River Delta (YRD). Polyurethane foam based passive air samplers were used to collect the atmospheric PAHs from 31 sampling sites in this area. PAHs concentrations ranged from 10.1 ng x m(-1) to 367 ng x m(-3) in this study. The annual average concentration of benzo [a] pyrene (BaP) reached 2.25 ng x m(-3), which was two times higher exceeding the national standard, GB 3095-2012. The atmospheric PAHs during four seasons decreased in the following order: autumn > winter > spring > summer. Larger BaP excessive areas were found in autumn and winter than other seasons. Moreover, an obvious emission of BaP was confirmed during the winter time. Traffic related petroleum combustion, coal and biomass burning, and coke oven were identified as potential sources of atmospheric PAHs, contributing 38.1%, 42.4%, and 19.5%, respectively.