[Assessment of Heavy Metal Pollution and its Health Risk of Surface Dusts from Parks of Kaifeng, China].

Fifty-two dust samples were collected from four parks [Longting Park (P(L)), Tieta Park (P(T)), Qingmingshanghe Park (P(Q)), Xiangguosi Park (P(X))] located in Kaifeng City, China. Concentrations of Hg and As in dusts were measured by atomic fluorescence spectrometry (AFS), while Cr, Cu, Zn, Pb, Ni and Cd were analyzed by inductively coupled plasma mass-spectrometry (ICP-MS). The heavy metal pollution of dust was assessed using Geo-accumulation index (Igeo) and pollution load index (PLI). The health risk due to exposure to heavy metals in dust was assessed using the model recommended by USEPA. The non-carcinogen (HI) and carcinogen health risks (TCR) were also calculated to evaluate the potential risks to adults. The results showed that the average contents of Hg, Cu, Zn, Cd and Pb were much higher than those in control samples and the background values of fluvo-aquic soil in China. The samples were seriously polluted by Hg and Pb, besides, there was.moderate pollution, slight pollution of Cu and Zn, and no pollution of As, Cr and Ni. The PLI from the 4 Parks indicated that there was serious heavy metals pollution of dust in P(X), moderate pollution in P%, and slight pollution in P(T) and P(Q). The average HI of heavy metals in the four Parks was lower than one. The average HI decreased in the order of P(L) > P(X), > P(T) > P(Q), while the average TCR decreased in the order of P(L) > P(Q) > P(x) > P(T). The contribution rate of HQ(As) to HI was about 43.51% , and that of CR(As) to TCR was about 70.11%.

A method of percutaneous vertebroplasty under the guidance of two C-arm fluoroscopes.

OBJECTIVE: To compare the clinical application in the percutaneous vertebroplasty under the guidance of one or two C-arm fluoroscopes. METHODS: One hundred forty three elderly patients with Osteoporotic vertebral compression fractures (OVCFs) underwent percutaneous vertebroplasty under the guidance of one or two C-arm fluoroscopes. The number of pulsed imagings, the time of operation and the incidence of cement leakage were recorded. RESULTS: The average number of pulsed imagings was 16.00±1.58 vs 13.07±2.00 per patient under the guidance of one vs two C-arm fluoroscopes. The average time of operation was 48.42±5.00 minutes vs 39.70±7.42 minutes per patient under the guidance of one vs two C-arm fluoroscopes. The incidence of cement leakage was 20% vs 15.7% of the patients under the guidance of one vs two C-arm fluoroscopes. The differences in the number of pulsed imagings and the time of operation were statistically significant. The difference in incidence of cement leakage was not statistically significant. CONCLUSION: The two-fluoroscopic technique reduce the labor cost, the radiation, the time of operation and the operation risk.

Bipolar hemiarthroplasty compared with internal fixation for unstable intertrochanteric fractures in elderly patients.

BACKGROUND: The optimal treatment for unstable intertrochanteric fractures in elderly patients remains controversial. We aimed to compare internal fixation and bipolar hemiarthroplasty for the treatment of unstable intertrochanteric fractures in elderly patients. METHODS: 124 patients aged over 70 years were enrolled into this study (64 internal fixations, 60 bipolar hemiarthroplasties). Patients were followed for two years, and had a clinical, radiological, and functional review at three, six, and twelve months as well as two years. RESULTS: In the internal fixation group, the fracture reduction and internal fixation were regarded as satisfactory in 44 cases and unsatisfactory in 20 cases. Five patients in the internal fixation group (two with satisfactory results and three with unsatisfactory results) and three patients in the arthroplasty group died before the final two-year follow-up. Five patients in the internal fixation group who had unsatisfactory results suffered complications. At 24 months post-operation, patients who were treated satisfactorily with internal fixation had higher Harris scores, less pain, and better walking ability than those treated with hemiarthroplasty and unsatisfactory internal fixation. CONCLUSIONS: Internal fixation with good reduction and fixation quality should be the preferred therapeutic method for elderly unstable intertrochanteric fractures, even when severe osteoporosis is present.

[Correlation of disability degree and Tile type of pelvic fracture caused by traffic accidents].

OBJECTIVE: To analyze the relevance of Tile type of pelvic fracture and the degree of disability and explore how to understand the malunion and severe malunion of pelvic fracture for the injured in the traffic accidents. METHODS: Eighty-six cases of pelvic fractures caused by traffic accidents from August 2008 to August 2011 in Forensic Judical Appraisal Institute of Suzhou Municipal Hospital were collected. At first, the grade of disability for every case was evaluated by 3 senior forensic experts independently. Then, the Tile type of pelvic fractures for every case was determined by 3 radiologists independently. At last, the correlation of the types of the fracture with the grades of disabilities was analyzed. RESULTS: In all the cases there were 19 cases determined as A-type fracture and evaluated as non-grade disability. There were 43 cases determined as B-type fracture. And in these cases there were 41 cases determined as tenth grade of disability, one case as non-grade disability and one case as ninth grade disability. There were 24 cases determined as C-type fracture. And in these cases there were 14 cases evaluated as tenth grade disability and 10 cases evaluated as ninth grade disability. There was a correlation between the grade of disability and the type of the fracture (r = 0.760). CONCLUSION: The disability degree caused by pelvic fracture correlates significantly with the type of the fracture. The finding is potentially useful to understand the malunion and severe malunion of pelvic fracture in forensic practice.

Sorption to dissolved humic acid and its impacts on the toxicity of imidazolium based ionic liquids.

Two typical ionic liquids (ILs), 1-butyl-3-methylimidazolium chloride ([C4MIM]Cl) and 1-octyl-3-methylimidazolium chloride ([C8MIM]Cl), are demonstrated to associate strongly with dissolved organic matter (DOM) with distribution coefficients (KDOC) in the range of 10(4.2) to 10(4.6) for Aldrich humic acid (used as model DOM). With the increase of humic acid concentration to 11 µg/mL DOC (dissolved organic carbon), the free fraction (ratio of freely dissolved to total concentration) of [C4MIM]Cl and [C8MIM]Cl reduced to about 0.85 and 0.79, respectively. This reduction of freely dissolved concentration gave rise to remarkable reduction of bioavailability and toxicity of the two ILs. MTT assay with HepG2 cell lines showed that the EC50 values were 459 µmol/L for [C4MIM]Cl and 12 µmol/L for [C8MIM]Cl, respectively, and the cell viability increased about 50% in the presence of trace amount of humic acid (1 µg/mL DOC). The SOS/umu test indicated mutagenicity for [C4MIM]Cl at levels above 664 µmol/L, and the genotoxicity was diminished with the addition of trace humic acid (0.00000374-0.374 µg/mL DOC). The studied ILs showed acute toxicity toward model fish medaka with a 96 h median lethal concentration (LC50) of 2254 µmol/L for [C4MIM]Cl and 366 µmol/L for [C8MIM]Cl. The addition of humic acid (5.49 µg/mL DOC for [C8MIM]Cl, 1.37 µg/mL DOC for [C4MIM]Cl) to IL solutions reduced the death rate of medaka to a minimum value of ∼25% of that at zero DOC. Our results suggest that DOM may play an important role in determining the environmental fate and toxicity of imidazolium-based ILs, and its effects should be taken into account in assessing the environmental risk of ILs.

Development of negligible depletion hollow fiber membrane-protected liquid-phase microextraction for simultaneous determination of partitioning coefficients and acid dissociation constants.

A new method based on negligible depletion hollow fiber-protected liquid-phase microextraction coupled with high-performance liquid chromatography (HPLC) was developed for the simultaneous determination of partitioning coefficients (K(OW)) and acid dissociation constants (pK(a)), by using phenol, 4-chlorophenol and 2,4-dichlorophenol as model compounds. A 37-mm length polypropylene hollow fiber membranes (600 microm inner diameter, 200 microm wall-thickness, 0.2 microm pore size, approximately 70% porosity) with two-end sealed were filled with 1-octanol by ultrasonic agitation to prepare the extraction device. The extraction device was deployed in sample solutions, prepared by spiking target analytes in 1-octanol saturated aqueous solutions (500 mL), for negligible depletion extraction. After equilibrium was reached ( approximately 5h), the 1-octanol in the lumen of the hollow fiber membrane was collected for HPLC determination of the target analytes. As the depletion of the analytes in aqueous samples was negligible, the distribution coefficient (D(OW)) could be calculated based on the measured equilibrium concentration in 1-octanol (C(O)) and the initial concentration (C(W)) in the aqueous sample of the target analyte (D(OW)=C(O)/C(W)). The D(OW) values measured at various pH values were nonlinearly regressed with pH to obtain the K(OW) and pK(a) values of a compound. Results showed that the measured values of the K(OW) and pK(a) of these model compounds agreed well with literature data.

Composition, antimicrobial activity and cytotoxicity of essential oils from Aristolochia mollissima.

The compositions of the essential oils from the rhizome and the aerial part of Aristolochia mollissima were analysed by GC-MS, 68 constituents (88.2% of the total oil) and 74 constituents (89.4% of the total oil) were identified, respectively. 2,2,7,7-Tetramethyltricyclo[6.2.1.0(1,6)]undec-4-en-3-one was the most abundant constituent among all in the ratios of 15.9% and 13.5% from the rhizome and the aerial part of A. mollissima, respectively. Among other main compounds, (E)-ß-santalol acetate (10.3%) and camphene (6.7%) were detected in the rhizome oil, spathulenol (6.8%) was detected in the oil from the aerial par of A. mollissima. The antimicrobial activity of the essential oils from the rhizome and the aerial part of A. mollissima was evaluated against 20 microorganisms using disc diffusion and broth microdilution methods. The gram-positive bacteria were more sensitive to both oils than gram-negative bacteria and yeasts. The rhizome oil showed the strongest bactericidal activity against Staphylococcus saprophyticus, whereas the oil from the aerial part of A. mollissima exerted the strongest bactericidal activity against methicillin-resistant and methicillin-senstive Staphylococcus aureus. The in vitro cytotoxicity of both oils on six human cancer cell lines were also examined. The cytotoxicity of the rhizome oil on four cancer cell lines (ACHN, Bel-7402, Hep G2 and HeLa) was significantly stronger than that of the oil from the aerial part of A. mollissima.

Identification of intermediate and product from methemoglobin-catalyzed oxidation of o-phenylenediamine in two-phase aqueous-organic system.

Methemoglobin (metHb) was used as a mimetic enzyme for peroxidase to catalyze the oxidation reaction of o-phenylenediamine (OPDA) with H2O2 functioning as an oxidant. A reaction intermediate was obtained in two-phase aqueous-organic system and an absorption peak at 710 nm was confirmed to be that of the intermediate in relation to OPDA. The isolated product and intermediate were characterized by UV-Vis and IR spectrophotometry and HPLC-tandem mass spectrometry. The results showed that the product is 2,3-diaminophenazine, the molecular mass of the intermediate is 212 daltons, and a conceivable structure of the intermediate is suggested. Combining the catalyzed reaction mechanism of peroxidase and our experimental results, a conceivable oxidation reaction mechanism of OPDA and H2O2 using metHb as catalyst is proposed.