[A Comparison of Arsenic Speciation in 13 Pteris vittata L. Populations].

Synchrotron radiation X-ray absorption near edge structure was employed to study the arsenic (As) speciation in 13 Pteris vittata L. populations collected from 7 provinces, cities, and autonomous regions in China. As in roots of P. vittata was mainly combined with oxygen (O), with a small amount of As combined with glutathione (GSH). Populations from Hunan and Guangxi provinces showed higher percentages of As-GSH in soots. As in roots of P. vittata was predominated with As(V), with the percentage of As(V) to the total As being 59.6±0.6%~83.8±3.8%. The As(V) percentage was in the order of HN5HN3>HN1>TW>CQ>AH>FJ>HN5>HN2>GX2>GX3>HN4>GX1, within the range of 2.4%~12.9%. Different from that in roots, As in shoots was predominated with As(III), with no As(V) detected. The disclosure of As speciation in the roots and shoots of P. vittata contributes to the future research on As accumulation mechanism.

A Clinical Study of Platelet-Rich Fibrin Combined With Autologous High-Density Fat Transplantation in Augmentation Rhinoplasty.

OBJECTIVE: This study was designed to analyze the clinical effect of autologous fat-granule transplantation in augmentation rhinoplasty and explore methods to improve the fat retention rate. METHODS: A total of 70 enrolled patients were randomly divided into 2 groups: the platelet-rich fibrin (PRF) combined with high-density fat transplantation group (combined group) and the conventional fat-granule transplantation group (control group; n = 35 in each group). In the combined group, an appropriate amount of autologous fat was extracted and centrifuged, and the lower layer of high-density fat was taken and mixed with PRF isolated from whole blood for autotransplantation. In the control group, only fat was extracted and centrifuged for transplantation. The patients were followed up with for more than one year to observe the short- and long-term effects, complications, safety, and patient satisfaction. RESULTS: Six months after the operation, the nasal shape was stable, the contour was higher and more stereoscopic than before, the average increase of nasal height was 3.0 mm in the combined group and 2.0 mm in the control group. No complications, such as fat embolism, infection, or necrosis occurred during the 1-year follow-up. The satisfaction rate between the 2 groups has statistical significance (P < .05). CONCLUSION: Overall, PRF combined with autologous high-density fat transplantation is simple to perform, has a significantly increased fat-retention rate than the control group, and has stable long-term effects without obvious adverse reactions. A sufficient amount of fat and PRF transplantation can achieve a good orthopedic effect. Thus, this method can be widely used in clinical augmentation rhinoplasty.

Clinical Application of a Bird-Beak-Type Z-Shaped Asymmetrical Flap in the Reconstruction of the Inner Canthus.

Objective: To introduce a new surgical method for the repair of a large inner canthus combined with tissue loss at the inner canthal angle of the eye by using a bird-beak-type z-shaped asymmetrical flap and to summarize its clinical effect. Method: A total of 56 patients with a large inner canthus were randomly selected, and a bird-beak-type z-shaped asymmetrical flap was used on the nasal side of the lower eyelid to repair and reconstruct the inner canthal folds. The inner canthal point was located according to physiological aesthetics. The short and long arms of the z-shaped asymmetrical flap were separated, replaced, fixed, and shaped to reconstruct the skin folds of the inner canthus and restore its aesthetic morphology. Results: All incisions after surgery achieved primary healing, and all 56 cases were followed up for 6-20 months (average 8.6 months). The caruncula lacrimalis was moderately exposed, the inner canthal angles possessed a natural appearance, and the results of the surgery were satisfactory. Five patients developed scar hyperplasia within one month after surgery, and arnica gel was applied topically for 3-6 months until the scar faded or disappeared, but no obvious scars were seen in the surgical area of the remaining patients. In two patients, the internal canthi were asymmetrical, but this improved after adjustment. Conclusion: Repair of a large inner canthus and tissue loss at the inner canthal angle of the eye using a bird-beak-type z-shaped asymmetrical flap is a simple operation, resulting in minimal trauma. Postoperatively, the inner canthal angle possessed a natural appearance with no obvious scarring.

Simultaneous compartmentalization of lead and arsenic in co-hyperaccumulator Viola principis H. de Boiss.: an application of SRXRF microprobe.

The cellular distributions of Pb and As in the leaves of co-hyperaccumulator Viola principis H. de Boiss. were inspected by synchrotron X-ray fluorescence spectroscopy (SRXRF). The results revealed that Pb and As had similar compartmentalization patterns in the leaves. Both elements were enriched in the bundle sheath and the palisade mesophyll. In comparison with the sheath and the mesophyll, the vascular bundle and the epidermis contained lower levels of Pb and As. The palisade enrichment of Pb and As indicated that V. principis H. de Boiss. may have a special mechanism on detoxification of toxic metals within the mesophyll cells. Relative concentrations of both Pb and As in trichome bases were higher than those in trichome rays. The results of hierarchical cluster analysis and correlation analysis confirmed that the distribution of Pb was similar to that of As in the leaves, and their distribution patterns were different from the nutrient elements, such as K, Ca, Mn, Fe, Ni, Cu and Zn. In vivo cellular localization of Pb and As in the leaves provides insight into the physiological mechanisms of metal tolerance and hyperaccumulation in the hyperaccumulators.

Arsenic uptake and transport of Pteris vittata L. as influenced by phosphate and inorganic arsenic species under sand culture.

In order to understand the similarity or difference of inorganic As species uptake and transport related to phosphorus in As-hyperaccumulator, uptake and transport of arsenate (As(V)) and arsenite (As(III)) were studied using Pteris vittata L. under sand culture. Higher concentrations of phosphate were found to inhibit accumulation of arsenate and arsenite in the fronds of P. vittata. The reduction in As accumulation was greater in old fronds than in young fronds, and relatively weak in root and rhizome. Moderate increases, from 0.05 to 0.3 mmol/L, in phosphate reduced uptake of As(III) more than As(V), while the reverse was observed at high concentrations of phosphate (> or = 1.0 mmol/L). Phosphate apparently reduced As transport and the proportion of As accumulated in fronds of P. vittata when As was supplied as As(V). It may in part be due to competition between phosphorus and As(V) during transport. In contrast, phosphate had a much smaller effect on As transport when the As was supplied as As(III). Therefore, the results from present experiments indicates that a higher concentration of phosphate suppressed As accumulation and transport in P. vittata, especially in the fronds, when exposed to As(V); but the suppression of phosphate to As transport may be insignificant when P. vittata exposed to As(III) under sand culture conditions. The finding will help to understand the interaction of P and As during their uptake process in P.

Effect of arsenic on chloroplast ultrastructure and calcium distribution in arsenic hyperaccumulator Pteris vittata L.

This study investigated the impacts of arsenic (As) on the chloroplast ultrastructure and calcium (Ca) distribution in Chinese brake (Pteris vittata L.) mainly by histochemical methods, with an emphasis on the possible function of Ca in As detoxification and accumulation in P. vittata. P. vittata was grown in an artificially contaminated soil added with different concentrations of Na(2)HAsO(4) (0, 100, 300 and 800 mg kg(-1) As dry soil) for 24 weeks in a greenhouse. The addition of As did not affect the chloroplast ultrastructure of young pinna, meanwhile most of the membrane systems of chloroplasts in mature pinna were severely damaged under high As condition. Calcium concentration in the fronds of P. vittata was not significantly affected by the addition of As, but Ca concentration in the mature pinna significantly increased by As addition, consistent with the position appearing As toxicity. When no As was added, most of calcium precipitates distributed around the inner membrane of vacuole. But when the pinna appeared plasmolysis, more calcium precipitates resided outside the cell membrane and bigger particles evenly distributed in the cytoplasm. All the results indicated that Ca had a close relation with As toxicity in P. vittata.

Zinc tolerance and accumulation in Pteris vittata L. and its potential for phytoremediation of Zn- and As-contaminated soil.

A field investigation and pot experiments were conducted to determine the potential of arsenic (As) hyperaccumulator, Pteris vittata L., to remediate sites co-contaminated with zinc (Zn) and As. We found that P. vittata L. had a very high tolerance to Zn and grew normally at sites with high Zn concentrations. In addition, P. vittata L. could effectively take up Zn into its fronds, with a maximum of 737 mg kg(-1) under field conditions. In pot experiments, the accumulated Zn concentration increased significantly as the Zn treatment was raised from 0 to 2000 mg kg(-1), with a maximum Zn accumulation of 0.22 mg pot(-1). Although the concentration of As in P. vittata L. was reduced by the addition of Zn, total frond accumulation of As was elevated when the Zn treatment was increased from 0 to 1000 mg kg(-1), with a maximum As accumulation of 8.3 mg pot(-1) in the presence of 1000 mg kg(-1) Zn. The high Zn tolerance, relatively high ability to accumulate Zn, and great capacity to accumulate As under conditions of suppression by high Zn suggest that P. vittata L. could be useful for the remediation of sites co-contaminated with Zn and As.

Assessment of heavy metal pollution in surface soils of urban parks in Beijing, China.

Assessing the concentration of potentially harmful heavy metals in the soil of urban parks is imperative in order to evaluate the potential risks to residents and tourists. To date, little research on soil pollution in China's urban parks has been conducted. To identify the concentrations and sources of heavy metals, and to assess the soil environmental quality, samples were collected from 30 urban parks located in the city of Beijing. Subsequently, the concentrations of Cu, Ni, Pb and Zn in the samples were analyzed. The investigation revealed that the accumulations of Cu and Pb were readily apparent in the soils. The integrated pollution index (IPI) of these four metals ranged from 0.97 to 9.21, with the highest IPI in the densely populated historic center district (HCD). Using multivariate statistic approaches (principal components analysis and hierarchical cluster analysis), two factors controlling the heavy metal variability were obtained, which accounted for nearly 80% of the total variance. Nickel and Zn levels were controlled by parent material in the soils, whereas Cu, Pb and, in part, Zn were accounted for mainly by anthropogenic activities. The findings presented here indicate that the location and the age of the park are important factors in determining the extent of heavy metal, particularly Cu and Pb, pollution. In addition, the accumulation of Zn did not appear to reach pollution levels, and no obvious pollution by Ni was observed in the soils of the parks in Beijing.

Ambient air temperature effects on the temperature of sewage sludge composting process.

Using data obtained with a full-scale sewage sludge composting facility, this paper studied the effects of ambient air temperature on the composting temperature with varying volume ratios of sewage sludge and recycled compost to bulking agent. Two volume ratios were examined experimentally, 1: 0: 1 and 3: 1: 2. The results show that composting temperature was influenced by ambient air temperature and the influence was more significant when composting was in the temperature rising process: composting temperature changed 2.4-6.5 degrees C when ambient air temperature changed 13 degrees C. On the other hand, the influence was not significant when composting was in the high-temperature and/or temperature falling process: composting temperature changed 0.75-1.3 degrees C when ambient air temperature changed 8-15 degrees C. Hysteresis effect was observed in composting temperature's responses to ambient air temperature. When the ventilation capability of pile was excellent (at a volume ratio of 1:0:1), the hysteresis time was short and ranging 1.1-1.2 h. On the contrary, when the proportion of added bulking agent was low, therefore less porosity in the substrate (at a volume ratio of 3:1:2), the hysteresis time was long and ranging 1.9-3.1 h.

A comparison of arsenic accumulation and tolerance among four populations of Pteris vittata from habitats with a gradient of arsenic concentration.

Arsenic (As) contamination poses a high risk to human health. Phytoremediation based on As hyperaccumulator Pteris vittata has been utilized on large areas of contaminated farmland in southern China. However, the reason for the observed differences in As removal among P. vittata populations remains unclear. In this study, spores of four P. vittata populations were collected from four neighboring sites with varying soil As concentration (from 108 mg·kg(-1) to 7527 mg·kg(-1)) and then cultured in a controlled environment to analyze their differing abilities in terms of As accumulation and tolerance. The results indicate that populations from low-As habitats exhibited 80% greater shoot As concentrations compared with those from high-As habitats. On the other hand, populations from high-As habitats exhibited approximately five times greater biomass compared with those from low-As habitats when exposed to the same As stress. Thus, the As accumulation and tolerance of P. vittata were suggested to be two independent processes. Further investigations reveal that the As absorption and As species conversion occurring in roots are two essential activities that bridge the soil As concentration and the responses of P. vittata to As. Depending on the As concentration of the target soil, the selection of different P. vittata populations can result in approximately an eight-fold difference in terms of remediation efficiency.

[Excretion of manure-borne steroid hormones and their potential risk in the three northeast provinces of China].

The excretion of manure-borne steroid hormones, including estrogens and androgens in Liaoning, Jilin and Heilongjiang province was estimated in this study on the basis of statistical data and by using the referenced estimation method in developed countries. In addition, the potential ecological risk of manure-borne steroid estrogens to local surface water systems from applying animal manure was preliminarily assessed. As a result of the rapid development of animal production, the excretions of manure-borne steroid hormones increased in all the three northeast provinces. In 2008, the emissions of total manure-borne estrogens and androgens increased by 2 272.7, 1 951.1 and 1 634.8 kg compared to those in 1998 in Liaoning, Jilin and Heilongjiang provinces, respectively. Especially, the growth rates in the three capital cities of Shenyang, Changchun and Harbin were the fastest among their own provinces. The largest emissions of manure-borne steroid hormones, as well as the highest concentration of predicted estradiol equivalency (EEQs) in the surface water system were found in Liaoning province. According to the lowest observable effect concentration for 17beta-estradiol (10 ng x L(-1)) recommended by the Environmental Agency of United Kingdom, 17.1 ng x L(-1) of EEQs level in Liaoning province might have become a potential risk to local surface water systems.

[Sorption of 17beta-estradiol to soils and sediment and influence of pig manure DOM].

Natural steroid estrogens such as 17beta-estradiol (E2) with low concentrations (ng x L(-1)) can adversely affect the reproductive health of aquatic organisms. Batch equilibrium experiments were conducted to quantify the sorption of E2 to two agricultural soils and a river sediment from different physiographic regions in northern China, a critical step in predicting transport of estrogens in runoff from agricultural fields. Meanwhile, the effect of pig manure and its compost borne dissolved organic matter (DOM) on E2 sorption was investigated. The Freundlich isotherm provided a good fit to model the sorption of E2 to agricultural soils and the sediment (R2 > 0.76). E2 adsorption nonlinearity was found for alluvial soil, black soil and the sediment, most isotherm deviation from linearity occurred in black soil (n = 0.74). The sorption of E2 to agricultural soil and sediment was correlated to the organic carbon content of each soil/sediment (P<0.05) with K(f) values ranging from 26.2 to 57.5. It was also found that the presence of DOM decreased estrogen sorption in soils and sediment, especially manure compost borne DOM. These results suggest that E2 was mostly adsorbed on organic matter in soil and sediment, and coexisted pig manure DOM could increase mobility at low concentration level and enhance the risk of E2 transport to ground and surface waters.

First evidence on different transportation modes of arsenic and phosphorus in arsenic hyperaccumulator Pteris vittata.

Arsenic (As) reduction and translocation are key processes for As hyperaccumulation by the hyperaccumulator Pteris vittata L. Micro-X-ray adsorption spectroscopy of P. vittata's rhizoid tissues revealed that As reduction mainly occurred in endodermis during translocation from epidermis to vascular bundle. Prior to reduction, arsenate (As (V)) translocation was an active process requiring energy and employing a phosphate (P) transporter. Use of a synchrotron X-ray microprobe showed that As (V) and P were cotransported and that this process could be enhanced by As (V) exposure or P deficiency but restrained by energy release inhibition caused by 2,4-dinitrophenol or sodium orthovanadate. In contrast, after As reduction, As(III) translocation differed from P translocation and was more efficient, appearing free from the apparent endodermal blockage. The results here revealed the role of the P transporter on As translocation as well as the key role of As reduction in As hyperaccumulation by P. vittata.

Sexual propagation of Pteris vittata L. influenced by pH, calcium, and temperature.

We aimed to optimize germination and growth conditions of the arsenic hyperaccumulating fern, Pteris vittata L. Pot experiments were carried out to investigate the effects of soil pH, soil calcium (Ca) concentration, and temperature on the sexual propagation of P. vittata. At 25 degrees C, germination was both accelerated and increased by high soil pH and Ca concentration. Spores of P. vittata did not germinate on medium with a pH of 4.6. Amending strongly acid soils with 27.5 or 40 micromol/g Ca(OH)2 significantly improved the growth rate during both the germination phase and the gametophyte phase. Amending strongly acid soils with NaOH (55 micromol/g) promoted germination, but did not affect subsequent growth. Among the different temperature, germination and growth rates were higher at 25 degrees C than at 20 degrees C or 30 degrees C. The distribution of P. vittata in China might be influenced by its requirement for high pH and high Ca concentration in the soil and appropriate growth temperature to complete sexual propagation. These results provided important information for improving breeding conditions of P. vitatta and will be helpful for extending the range of areas in which P. vittata can be used for phytoremediation.

[Physical and chemical properties of land-filling pile and aged refuse in 5-year-old semi-aerobic and anaerobic landfills].

This paper studied the surface settlement, temperature, and gas production of land-filling pile, and the physical and chemical properties of aged refuse in 5-year-old semi-aerobic and anaerobic landfills. The pile's surface settlement and its volume reduction rate were significantly higher in semi-aerobic than in anaerobic landfill; and the treatment with leachate recycling brought larger uneven settlement than the treatment with water recycling. The temperature of anaerobic landfill pile (25.6 degrees C) was slightly higher than that of semi-aerobic landfill file (24.8 degrees C), but the difference was not significant. During land-filling period, the O2 concentration in semi-aerobic landfill pile was significantly higher than that in anaerobic one, while the CH4 concentration was in reverse. After 5 years land-filling, the contents of easily degradable organic matters in aged refuse, such as kitchen refuses and papers, decreased dramatically, while the contents of plastics, glasses, bricks, and woods increased. In addition, the contents of organic matters and nutrients in aged refuse were higher than those in typical southern China soils, and the concentrations of heavy metals except chromium in anaerobic landfill aged refuse were not beyond the grade three of Environmental Quality Standards for Soils (GB 15618-1995).

Difference of toxicity and accumulation of methylated and inorganic arsenic in arsenic-hyperaccumulating and -hypertolerant plants.

The arsenic (As) hyperaccumulators, Pteris vittata and Pteris cretica and an As-tolerant plant Boehmeria nivea, were selected to compare the toxicity, uptake, and transportation of inorganic arsenate (As(V)) and its methylated counterpart dimethylarsinic acid (DMA). The XANES method was used to elucidate the effect of As species transformation on As toxicity and accumulation characteristics. Significantly higher toxicity and lower accumulation of DMAthan inorganic As(V) was shown in the As hyperaccumulators and the As-tolerant plant. Reduction of As(V) was commonly found in the plants. Arsenic complexation with thiols, which have less mobility in plants and usually occur in As-tolerant plants, was also found in rhizoids of P. cretica. Plants with greater ability to form As-thiolate have lower ability for upward transport of As. Demethylation of DMA occurred in the three plants. The DMA component decreased from the rhizoids to the fronds in both hyperaccumulators, while this tendency is reverse in B. nivea.

Arsenic transformation and volatilization during incineration of the hyperaccumulator Pteris vittata L.

Safe incineration of harvested hyperaccumulators containing high content of heavy metals to avoid secondary environmental pollution is a problem for popularizing phytoremediation technology. The As volatilization behavior and its mechanism during incineration of Pteris vittata, an As-hyperaccumulator, was investigated. Incineration results reveal that 24% of total As accumulated by P. vittata (H-As) containing high As content (1170 mg/kg) is emitted at 800 degrees C, of which 62.5% of the total emitted As is volatilized below 400 degrees C. A study of the extended X-ray absorption fine structure (EXAFS) shows that part of As(III) was identified in the thermal decomposition residue of dried P. vittata (H-As), As2O5 + P. vittata (L-As) containing low As content (14.7 mg/kg), and As2O5 + charcoal (C) at 200 degrees C, suggesting that carbon originating from biomass incineration might catalyze As(V) reduction. This speculation was tested through thermogravimetric experiments, in which either C or P. vittata (L-As) markedly catalyzed the volatilization of pure As2O5 at low temperature. Therefore, the reduction of As(V) to As(III) is responsible for As volatilization during incineration of P. vittata below 400 degrees C. This study provides important insights into As behavior during incineration of As-hyperaccumulators, which is helpful to safely dispose harvested biomass with high As content.

[Clinical observation of the efficacy of MEBO in the treatment of burn patients with burn area over 50% TBSA].

OBJECTIVE: To observe the effectiveness of MEBO in the treatment of burn patients with burn area over 50% TBSA. METHODS: Two hundred and ninety-eight patients hospitalized in our hospital from May of 1991 to December of 2003 with burn area over 50% TBSA, who had MEBO treatment before hospitalization, were enrolled in the study as the experiment (E) group. Another group of 300 burn patients with burn area over 50% TBSA that treated with SD-Ag cream were enrolled in the study as the control (C) group. Bacterial culture results, major changes in injury and mortality were compared between the two groups. RESULTS: There were 1 506 bacteria strains isolated from wounds in E group, and 9 main changes in injury (1679 cases) occurred with 20.8% mortality in this group. There were 353 bacteria strains isolated, with occurrence of 9 changes in injury (518 cases) and 4.7% mortality in the SD-Ag group. CONCLUSION: MEBO is much less effective for the treatment of the burn patients with large burn area compared with SD-Ag cream treatment.

[As-hyperaccumulation of Pteris vittata L. as influenced by as concentrations in soils of contaminated fields].

As soil arsenic concentration might have great effect on arsenic accumulation of hyperaccumulator Pteris vittata L. , three sample areas with different As pollution level in the soils are investigated in Chenzhou, Hunan Province, where Pteris vittata L. grows broadly. Great variation of As concentrations is found to be not only among different samples in the same sampling areas but also between rhizosphere and bulk soil of P. vittata L. So it is suggested that rhizosphere soil should be sampled to study the effect of soil contamination on plant accumulation. The As concentration in frond of P. vittata L. increased dramatically at lower As level but decreased slowly when As concentration higher than 1 000 mg/kg. Arsenic translocation factors of P. vittata L. were greater than 1 in all samples in this study, whereas As concentration in shoots in lower As contaminated soil and bioaccumulation factors in higher As contaminated soil are fail to meet the definition of As hyperaccumulator.